bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protective effects of insulin on polychlorinated biphenyls‐induced disruption of actin cytoskeleton in hippocampal neurons
Authors: Tang Feige , Yan Chonghuai , Li Fei , Wu Shenghu , Yu Yongguo , Gao Yu , Jin Xingming , Tian Ying , Shen Xiaoming 
Published: March 2007

AbstractInsulin receptors are widely distributed in the brain, and insulin improves learning and memory in some brain injury. Insulin elevates LIM kinase 1 (LIMK‐1) activity and induces actin polymerization in some cells, while actin cytoskeleton dynamics mediated via LIMK‐1/cofilin signal pathway is considered important to learning and memory formation. Our previous studies have shown that polychlorinated biphenyls (PCBs) disrupt the actin cytoskeleton by inhibiting LIMK‐1/cofilin signaling pathway in the cultured hippocampal neurons. To determine potential neuronal protective effects by insulin, we administered insulin to the cultured hippocampal neurons after exposure to PCBs mixture Aroclor 1254 (A 1254). We found that insulin antagonized a loss of filamentous actin and the cytotoxicity induced by A 1254. Similarly, insulin restored the decrease of LIMK‐1 and cofilin phosphorylation induced by A 1254. We concluded that insulin could protect neurons, probably partly by ameliorating filamentous actin cytoskeleton disruption mediated via the activation of LIMK‐1/cofilin signal pathway in cultured hippocampal neurons after exposure to A 1254. The above protective effects in hippocampal neuron may have important implications in the treatment of PCBs‐induced neurotoxicity and the mechanism by which insulin improves learning and memory. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 152–158, 2007.
Sampling and analysis of microcystins: Implications for the development of standardized methods
Authors: Tillmanns Angeline R. , Pick Frances R. , Aranda‐Rodriguez Rocio 
Published: March 2007

AbstractMicrocystins (MC), a group of cyanotoxins, have been found in lakes and rivers worldwide. One goal of MC research is to develop models which predict MC concentrations, but these efforts have been hampered by a lack of standardized methods necessary for comparing data across studies. Here, we investigate the effect of chemical analysis (HPLC‐PDA and ELISA), sample collection (whole water, plankton tow and surface scum), and choice of normalizing parameter (volume, dry weight, and chlorophyll a) on reported MC concentrations. Samples were collected over three years from a temperate mesotrophic, shallow lake with episodic blooms of cyanobacteria. We found that microcystins were up to four times higher in lake samples when analyzed by ELISA relative to HPLC‐PDA and that MC concentration measured by HPLC explained less than half of the variation in MC concentrations measured by ELISA. Also, samples collected by plankton tow gave consistently higher concentrations than whole water samples. An additional HPLC analysis of two chlorophyte cultures revealed the presence of compounds with a similar UV absorbance spectrum to MC‐LR, suggesting that identifying MC based solely on UV absorbance is not valid. Our results document the discrepancy in MC concentrations that can arise by using different methods throughout all stages of sampling, analysis, and reporting of MC concentrations. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 132–143, 2007.
Effect of dibutyltin on ATP levels in human natural killer cells
Authors: Dudimah Fred D. , Gibson Constance , Whalen Margaret M. 
Published: March 2007

AbstractThis study investigates the role that decreased ATP levels may play in dibutyltin (DBT)‐induced decreases in the tumor‐cell‐lysing (lytic) function of natural killer (NK) cells. NK cells are a subset of lymphocytes capable of killing tumor cells, virally infected cells, and antibody coated cells. DBT is used as stabilizer in PVC plastics and has also been used as a deworming product in poultry. NK cells were exposed to various concentrations of DBT for 1 h, 24 h, 48 h, and 6 days before determining ATP levels and lytic function. ATP levels and lytic function were also determined in NK cells that were exposed to DBT for 1 h followed by 24 h, 48 h, and 6 days in DBT‐free media. The results indicated that exposure of NK cells to 10 μM DBT for 1 h did not cause any significant decrease in NK cell ATP levels but did cause a very significant loss in lytic function. NK cells exposed to 500 nM DBT for 24 h showed significant loss of lytic function but showed no decrease in ATP levels. However, 48 h and 6 days exposures to those concentrations of DBT that caused decreases in tumor lysing function also caused significant decreases in ATP levels. Exposures of NK cells to varying DBT concentrations for 1 h followed by 24 h, 48 h, and 6 days in DBT free media produced effects on lytic function and ATP levels that were similar to those seen with continuous DBT exposures. The results indicate that DBT exposures decrease ATP levels in NK cells but that tumor lysing function can be reduced independent of any decreases in ATP levels. Additionally the results show that the effects of a range of DBT concentrations on ATP levels and tumor lysing function are irreversible. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 117–123, 2007.
Pleural and pericardial effusion: a potential ultrasonographic marker for the prenatal differential diagnosis between congenital diaphragmatic eventration and congenital diaphragmatic hernia
Authors: Jeanty C. , Nien J. K. , Espinoza J. , Kusanovic J. P. , Gonçalves L. F. , Qureshi F. , Jacques S. , Lee W. , Romero R. 
Published: March 2007

AbstractObjectivesTo determine whether or not the presence of pleural and/or pericardial effusion can be used prenatally as an ultrasonographic marker for the differential diagnosis between diaphragmatic eventration and diaphragmatic hernia.MethodsWe present two case reports of non‐isolated diaphragmatic eventration associated with pleural and/or pericardial effusion. Additionally, we reviewed the literature for all cases of congenital diaphragmatic hernia (CDH) and diaphragmatic eventration that met the following criteria: (1) prenatal diagnosis of a diaphragmatic defect and (2) definitive diagnosis by autopsy or surgery. The frequencies of pleural effusion, pericardial effusion and hydrops were compared between the two conditions using Fisher's exact test. A subanalysis was conducted of cases with isolated diaphragmatic defects (i.e. diaphragmatic defects not associated with hydrops and other major structural or chromosomal anomalies).ResultsA higher proportion of fetuses with diaphragmatic eventration had associated pleural and pericardial effusions compared with fetuses with diaphragmatic hernia (58% (7/12) vs. 3.7% (14/382), respectively, P < 0.001). This observation remained true when only cases of diaphragmatic defects not associated with hydrops and other major structural or chromosomal anomalies were compared (29% (2/7) with eventration vs. 2.2% (4/178) with CDH, P < 0.02).ConclusionsThe presence of pleural and/or pericardial effusion in patients with diaphragmatic defects should raise the possibility of a congenital diaphragmatic eventration. This information is clinically important for management and counseling because the prognosis and treatment for CDH and congenital diaphragmatic eventration are different. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
A new putative Zygosaccharomyces yeast species isolated from traditional balsamic vinegar
Authors: Solieri Lisa , Cassanelli Stefano , Giudici Paolo 
Published: March 2007

AbstractThe taxonomic status and species number of the genus Zygosaccharomyces have rapidly changed in the last years. In this study, two new osmotolerant Zygosaccharomyces strains isolated from traditional balsamic vinegar, viz. ABT301 and ABT601, were investigated to elucidate their taxonomic relationships with Zygosaccharomyces rouxii species. A multi‐gene sequence approach was employed, including regions of the rDNA repeat [5.8S, two internal transcribed spacers (ITS) and the 26S D1/D2 domain], COX2 mitochondrial gene and two nuclear genes (SOD2 and HIS3). Cloning and sequence analysis of 5.8S‐ITS rDNA revealed that these strains bear an unusual polymorphism for this region. Three highly divergent 5.8S‐ITS sequences were detected, one identical to Z. rouxii, the other two showing some relatedness to Z. mellis. Sequence and gene number polymorphism was also observed for the protein‐encoding nuclear genes SOD2 and HIS3, as two copies for each gene different from those found in Z. rouxii were detected. Analysis of the D1/D2 26S domain showed that ABT301 and ABT601 have only one type of D1/D2 sequence statistically different from that of Z. rouxii. The findings obtained in this work suggest that the genomic background of strains ABT301 and ABT601 is different from the other Zygosaccharomyces species. We speculated that they could belong to a new putative species related to Z. rouxii. Copyright © 2007 John Wiley & Sons, Ltd.
Genetic and reproductive consequences of forest fragmentation for populations of Magnolia obovata
Authors: Isagi Yuji , Tateno Ryunosuke , Matsuki Yu , Hirao Akira , Watanabe Sonoko , Shibata Mitsue 
Published: March 2007

AbstractIn order to evaluate the consequences of forest fragmentation on populations of Magnolia obovata, we compared genetic diversity and reproductive characteristics at two nearby sites, one conserved and one fragmented. The genetic diversity between adults trees of the different sites was not significantly different. However, saplings in the conserved site showed a significantly higher genetic diversity than both adult trees in the conserved site and saplings in the fragmented sites; this was found to be the result of the larger gene flow into the conserved site. The density of the adult trees was significantly related to all of the reproductive traits analyzed (fertilization of ovules, insect attack to seeds, ovules that developed into seeds and outcrossing at the stage of seeds) at both sites. At both sites, fertilization of ovules and insect attack on seeds were positively correlated to adult tree density while outcrossing rate was negatively correlated to adult tree density. The fertilization of ovules and outcrossing were more dependent on adult tree density in the fragmented site than in the conserved site. The probability of ovules developing into outcrossed seeds showed a negative correlation with adult tree density at both sites, indicating the advantage of low density for this species and possibly implying a resilience to habitat fragmentation. A two‐generation‐analysis did not identify significant differences between sites in terms of the structure of the pollen pool and the number of pollen donors. Although fragmentation affected reproductive characteristics, the effect on seedling establishment and subsequent survival remains to be determined. Proposals for future studies that will assist in the development of management strategies for forests suffering fragmentation are made.
Europe combating cancer: The European Union's commitment to cancer research in the 6th Framework Programme
Authors: Jungbluth Stefan , Kelm Olaf , van de Loo Jan-Willem , Manoussaki Elengo , Vidal Maria , Hallen Manuel , Trias Octavi Quintana 
Published: March 2007

AbstractAs one of the major health issues in Europe, cancer was a research priority in the 6th Framework Programme (2002–2006). About €485 million were devoted to this theme, which allowed funding of 108 multidisciplinary transnational projects. A significant part of them was large‐scale initiatives addressing complex issues through a broad combination of competences. All major types of cancer were covered, as well as the three dimensions such as prevention, diagnostic and treatment, with a particular emphasis on translational research aiming at bringing basic knowledge on medical practice. This approach will be continued in the 7th Framework Programme (2007–2013), together with a strengthened effort to improve the coordination of European cancer research, which is fragmented and in which EU action represents only a small part. EU cancer research will also be addressed within the reinforced efforts in the areas of pharmaceutical and technological developments as well as common aetiological mechanisms of diseases that the 7th Framework Programme will undertake.
Cancer therapeutic antibodies come of age: Targeting minimal residual disease
Authors: Ben-Kasus Tsipi , Schechter Bilha , Sela Michael , Yarden Yosef 
Published: March 2007

AbstractTen years after the first clinical application of Rituximab, an anti‐CD20 recombinant monoclonal antibody, immunotherapy has become common practice in oncology wards. Thanks to the great diversity of the immune system and the powerful methodology of genetic engineering, the pharmacologic potential of antibody‐based therapy is far from exhaustion. The recent application of Trastuzumab, an antibody to a receptor tyrosine kinase, in adjuvant breast cancer therapy marks the beginning of a new phase in cancer treatment. Here we discuss molecular mechanisms of antibody‐based therapy, the emerging ability to target minimal disease and the therapeutic potential of combining antibodies with other modalities.
Functional role of Meox2 during the epithelial cytostatic response to TGF‐β
Authors: Valcourt Ulrich , Thuault Sylvie , Pardali Katerina , Heldin Carl-Henrik , Moustakas Aristidis 
Published: March 2007

AbstractTransforming growth factor β (TGF‐β) suppresses epithelial cell growth. We have identified a new target gene of the TGF‐β/Smad pathway, Meox2, encoding the homeodomain transcription factor that is known to regulate endothelial cell proliferation and muscle development. Knockdown of endogenous Meox2 by RNA interference prevented the TGF‐β1‐induced cytostatic response. Moreover, ectopic Meox2 suppressed epithelial cell proliferation in cooperation with TGF‐β1, and mediated induction of the cell cycle inhibitor gene p21. Transcriptional induction of p21 by Meox2 required a distal region of the p21 promoter that spans the p53‐binding site. We show that Meox2 can form protein complexes with Smads leading to cooperative regulation of p21 gene expression. Finally, we found that in cell models that undergo both cell cycle arrest and epithelial–mesenchymal transition (EMT), ectopic Meox2 failed to induce EMT and inhibited the proper EMT response to TGF‐β. Thus, Meox2 is primarily involved in the TGF‐β tumor suppressor pathway.
The morphologies of breast cancer cell lines in three‐dimensional assays correlate with their profiles of gene expression
Authors: Kenny Paraic A. , Lee Genee Y. , Myers Connie A. , Neve Richard M. , Semeiks Jeremy R. , Spellman Paul T. , Lorenz Katrin , Lee Eva H. , Barcellos-Hoff Mary Helen , Petersen Ole W. , Gray Joe W. , Bissell Mina J. 
Published: March 2007

Abstract3D cell cultures are rapidly becoming the method of choice for the physiologically relevant modeling of many aspects of non‐malignant and malignant cell behavior ex vivo. Nevertheless, only a limited number of distinct cell types have been evaluated in this assay to date. Here we report the first large scale comparison of the transcriptional profiles and 3D cell culture phenotypes of a substantial panel of human breast cancer cell lines. Each cell line adopts a colony morphology of one of four main classes in 3D culture. These morphologies reflect, at least in part, the underlying gene expression profile and protein expression patterns of the cell lines, and distinct morphologies were also associated with tumor cell invasiveness and with cell lines originating from metastases. We further demonstrate that consistent differences in genes encoding signal transduction proteins emerge when even tumor cells are cultured in 3D microenvironments.
Characterization of breast precancerous lesions and myoepithelial hyperplasia in sclerosing adenosis with apocrine metaplasia
Authors: Celis Julio E. , Moreira José M.A. , Gromova Irina , Cabezón Teresa , Gromov Pavel , Shen Tao , Timmermans Vera , Rank Fritz 
Published: March 2007

AbstractThe identification as well as the molecular characterization of breast precancerous lesions in terms of increased risk of progression and/or recurrence is becoming a critical issue today as improved non‐surgical procedures are detecting cancer at an earlier stage. The strategy we have been pursuing to identify early apocrine breast lesions is based on the postulate that invasive apocrine carcinomas evolve from epithelial cells in terminal duct lobular units (TDLUs) in a stepwise manner that involves apocrine metaplasia of normal breast epithelia, hyperplasia, atypia, and apocrine carcinoma in situ. First, we identify specific protein biomarkers for benign apocrine metaplasia and thereafter we search for biomarkers that are highly overexpressed by pure invasive apocrine carcinomas. Here we present studies in which we have used antibodies against components of a benign apocrine signature that includes 15‐prostaglandin dehydrogenase (15‐PGDH), a protein that is expressed by all benign apocrine lesions, and markers that are highly overexpressed by pure invasive apocrine carcinomas such as MRP14 (S100A9), psoriasin (S100A7), and p53 to identify precancerous lesions in sclerosing adenosis (SA) with apocrine metaplasia. The latter is a benign proliferative lesion of the breast that exhibits an increase in the size of the TDLUs and characterized by retained two‐cell lining, and myoepithelial (ME) and stromal hyperplasia. SA with apocrine metaplasia, i.e. apocrine adenosis (AA), presents with a higher degree of atypical apocrine hyperplasia, and these lesions are believed to be precursors of apocrine carcinoma, in situ and invasive. Analysis of 24 selected SA samples with apocrine metaplasia revealed non‐obligate putative apocrine precancerous lesions that displayed some, or in same cases all the three markers associated with pure invasive apocrine carcinomas. These studies also revealed p53 positive, non‐apocrine putative precancerous lesions as well as novel phenotypes for ME and some luminal cells characterized by the expression of cytokeratin 15.
Mice thrive without Cdk4 and Cdk2
Authors: Barrière Cédric , Santamaría David , Cerqueira Antonio , Galán Javier , Martín Alberto , Ortega Sagrario , Malumbres Marcos , Dubus Pierre , Barbacid Mariano 
Published: March 2007

AbstractMammalian cell division is thought to be driven by sequential activation of several Cyclin‐dependent kinases (Cdk), mainly Cdk4, Cdk6, Cdk2 and Cdk1. Since mice lacking Cdk4, Cdk6 or Cdk2 are viable, it has been proposed that they play compensatory roles. We report here that mice lacking Cdk4 and Cdk2 complete embryonic development to die shortly thereafter presumably due to heart failure. However, conditional ablation of Cdk2 in adult mice lacking Cdk4 does not result in obvious abnormalities. Moreover, these double mutant mice recover normally after partial hepatectomy. In culture, Cdk4−/−;Cdk2−/−embryonic fibroblasts become immortal, display robust pRb phosphorylation and have normal S phase kinetics. These observations indicate that Cdk4 and Cdk2 are dispensable for the mammalian cell cycle and for adult homeostasis.
Palmitic acid increase levels of pancreatic duodenal homeobox-1 and p38/stress-activated protein kinase in islets from rats maintained on a low protein diet
Authors: Arantes Vanessa C. , Reis Marise A. B. , Latorraca Márcia Q. , Ferreira Fabiano , Stoppiglia Luiz Fabrízio , Carneiro Everardo M. , Boschero Antonio C. 
Published: March 2007

A severe reduction in insulin release in response to glucose is consistently noticed in protein-deprived rats and is attributed partly to the chronic exposure to elevated levels of NEFA. Since the pancreatic and duodenal transcription factor homeobox 1 (PDX-1) is important for the maintenance of β-cell physiology, and since PDX-1 expression is altered in the islets of rats fed a low protein (LP) diet and that rats show high NEFA levels, we assessed PDX-1 and insulin mRNA expression, as well as PDX-1 and p38/stress activated protein kinase 2 (SAPK2) protein expression, in islets from young rats fed low (6 %) or normal (17 %; control) protein diets and maintained for 48 h in culture medium containing 5·6 mmol/l glucose, with or without 0·6 mmol/l palmitic acid. We also measured glucose-induced insulin secretion and glucose metabolism. Insulin secretion by isolated islets in response to 16·7 mmol/l glucose was reduced in LP compared with control rats. In the presence of NEFA, there was an increase in insulin secretion in both groups. At 2·8 mmol/l glucose, the metabolism of this sugar was reduced in LP islets, regardless of the presence of this fatty acid. However, when challenged with 16·7 mmol/l glucose, LP and control islets showed a severe reduction in glucose oxidation in the presence of NEFA. The PDX-1 and insulin mRNA were significantly higher when NEFA was added to the culture medium in both groups of islets. The effect of palmitic acid on PDX-1 and p38/SAPK2 protein levels was similar in LP and control islets, but the increase was much more evident in LP islets. These results demonstrate the complex interrelationship between nutrients in the control of insulin release and support the view that fatty acids play an important role in glucose homeostasis by affecting molecular mechanisms and stimulus/secretion coupling pathways.
Zn-limited diet modifies the expression of the rate-regulatory enzymes involved in phosphatidylcholine and cholesterol synthesis
Authors: Gomez Nidia Noemí , Biaggio Verónica Silvina , Rozzen Esteban Javier , Alvarez Silvina Mónica , Gimenez María Sofía 
Published: March 2007

Suboptimal intake of Zn is one of the most common nutritional worldwide problems. Previously, we showed that Zn deficiency produces alterations in lung lipid metabolism in rats. We studied the effect of a Zn-limited (ZL) diet on the expression of the enzymes involved in phosphatidylcholine and cholesterol synthesis. After 2 months of treatment with a ZL diet we found important variations in the lipid content of Wistar male rats: triacylglycerol (TG) decreased 60 % (P < 0·001) while esterified cholesterol (EC), free cholesterol and phospholipids (PL) increased 66 %, 24 % and 25 % respectively. We also observed a decrease of 40 % in the amount of3H incorporated into TG and an increase of 47 % and 28 % in the3H incorporated to PL and EC respectively. Fatty acid synthase and glucose-6-phosphate dehydrogenase activity was increased (P < 0·01 andP < 0·05 respectively). Glycerol-3-phosphate acyltransferase, lipoprotein lipase, diacyl glycerol acyl transferase and 3-hydroxy-3-methylglutaryl CoA reductase expression decreased (P < 0·01 in all cases), while acetyl CoA carboxylase and cholinephosphate cytidylyltransferase increased (P < 0·01 andP < 0·005 respectively). These results suggest that ZL alters the expression of enzymes involved in phosphatidylcholine and cholesterol synthesis, which could lead to increased PL and cholesterol and decreased TG. This study suggests that major changes in the lipid composition of lung are induced by a ZL condition. Therefore, Zn deficiency must be taken into account in order to design therapies and public health interventions, such as Zn supplementation for high-risk subjects or certain diseases, such as asthma.