bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cdc42 negatively regulates intrinsic migration of highly aggressive breast cancer cells
Authors: Zuo Yufeng , Wu Yuexiu , Chakraborty Chandan 
Published: May 2011

AbstractThe small GTPase Cdc42 has been implicated as an important regulator of cell migration. However, whether Cdc42 plays similar role in all cancer cells irrespective of metastatic potential remains poorly defined. Here, we show by using three different breast cancer cell lines with different metastatic potential, the role of Cdc42 in cell migration/invasion and its relationship with a number of downstream signaling pathways controlling cell migration. Small interfering RNA (siRNA)‐mediated knockdown of Cdc42 in two highly metastatic breast cancer cell lines (MDA‐MB‐231 and C3L5) resulted in enhancement, whereas the same in moderately metastatic (Hs578T) cell line resulted in inhibition of intrinsic cellular migration/invasion. Furthermore, Cdc42 silencing in MDA‐MB‐231 and C3L5 but not Hs578T cells was shown to be accompanied by increased RhoA activity and phosphorylation of protein kinase C (PKC)‐δ, extracellular signal regulated kinase1/2 (Erk1/2), and protein kinase A (PKA). Pharmacological inhibition of PKCδ, MEK‐Erk1/2, or PKA was shown to inhibit migration of both control and Cdc42‐silenced MDA‐MB‐231 cells. Furthermore, introduction of constitutively active Cdc42 was shown to decrease migration/invasion of MDA‐MB‐231 and C3L5 but increase migration/invasion of Hs578T cells. This decreased migration/invasion of MDA‐MB‐231 and C3L5 cells was also shown to be accompanied by the decrease in the phosphorylations of PKCδ, Erk1/2, and PKA. These results suggested that endogenous Cdc42 could exert a negative regulatory influence on intrinsic migration/invasion and some potentially relevant changes in phosphorylation of PKCδ, Erk1/2, and PKA of some aggressive breast cancer cells. J. Cell. Physiol. 227: 1399–1407, 2012. © 2011 Wiley Periodicals, Inc.
Hyposmotic stress causes ATP release and stimulates Na,K‐ATPase activity in porcine lens
Authors: Shahidullah M. , Mandal A. , Beimgraben C. , Delamere N.A. 
Published: May 2011

AbstractPurinergic receptors in lens epithelium suggest lens function can be altered by chemical signals from aqueous humor or the lens itself. Here we show release of ATP by intact porcine lenses exposed to hyposmotic solution (200 mOsm). 18α‐glycyrrhetinic acid (AGA) added together with probenecid eliminated the ATP increase. N‐ethylmaleimide (200 µM), an exocytotic inhibitor, had no significant effect on ATP increase. Lenses exposed to hyposmotic solution displayed a ∼400% increase of propidium iodide (PI) entry into the epithelium. The increased ability of PI (MW 668) to enter the epithelium suggests possible opening of connexin and/or pannexin hemichannels. This is consistent with detection of connexin 43, connexin 50, and pannexin 1 in the epithelium and the ability of AGA + probenecid to prevent ATP release. Na,K‐ATPase activity doubled in the epithelium of lenses exposed to hyposmotic solution. The increase of Na,K‐ATPase activity did not occur when apyrase was used to prevent extracellular ATP accumulation or when AGA + probenecid prevented ATP release. The increase of Na,K‐ATPase activity was inhibited by the purinergic P2 antagonist reactive blue‐2 and pertussis toxin, a G‐protein inhibitor, but not by the P2X antagonist PPADS. Hyposmotic solution activated Src family kinase (SFK) in the epithelium, judged by Western blot. The SFK inhibitor PP2 abolished both SFK activation and the Na,K‐ATPase activity increase. In summary, hyposmotic shock‐induced ATP release is sufficient to activate a purinergic receptor‐ and SFK‐dependent mechanism that stimulates Na,K‐ATPase activity. The responses might signify an autoregulatory loop initiated by mechanical stress or osmotic swelling. J. Cell. Physiol. 227: 1428–1437, 2012. © 2011 Wiley Periodicals, Inc.
Hepatitis B virus X protein induces IKKα nuclear translocation via Akt‐Dependent phosphorylation to promote the motility of hepatocarcinoma cells
Authors: Huang Wei‐Chien , Chen Wen‐Shu , Chen Yun‐Ju , Wang Li‐Yun , Hsu Sheng‐Chieh , Chen Ching‐Chow , Hung Mien‐Chie 
Published: May 2011

AbstractHepatitis B virus (HBV) X protein (HBx) has been implicated in HBV‐associated carcinogenesis through activation of IκB kinase (IKK)/nuclear factor kappa B (NF‐κB) signaling pathway. Besides activating NF‐κB in the cytoplasm, IKKα was found in the nucleus to regulate gene expression epigenetically in response to various stimuli. However, it is unknown whether nuclear IKKα plays a role in HBx‐associated tumor progression. Moreover, the molecular mechanism underlying IKKα nuclear transport also remains to be elucidated. Here, we disclosed HBx as a new inducer of IKKα nuclear transport in hepatoma cells. HBx induced IKKα nuclear transport in an Akt‐dependent manner. HBx‐activated Akt promoted IKKα nuclear translocation via phosphorylating its threonine‐23 (Thr23). In addition, IKKα ubiquitination enhanced by HBx and Akt also contributed to the IKKα accumulation in the nucleus, indicating the involvement of ubiquitination in Akt‐increased IKKα nuclear transport in response to HBx. Furthermore, inhibition of IKKα nuclear translocation by mutation of its nuclear localization signal and Thr23 diminished IKKα‐dependent cell migration. Taken together, our findings shed light on the molecular mechanism of IKKα nuclear translocation and provide a potential role of nuclear IKKα in HBx‐mediated hepatocellular carcinoma (HCC) progression. J. Cell. Physiol. 227: 1446–1454, 2012. © 2011 Wiley Periodicals, Inc.
Cooperation between Shh and IGF‐I in promoting myogenic proliferation and differentiation via the MAPK/ERK and PI3K/Akt pathways requires smo activity
Authors: Madhala‐Levy D. , Williams V.C. , Hughes S.M. , Reshef R. , Halevy O. 
Published: May 2011

AbstractSonic Hedgehog (Shh) has been shown to promote adult myoblast proliferation and differentiation and affect Akt phosphorylation via its effector Smoothened (Smo). Here, the relationship between Shh and insulin‐like growth factor I (IGF‐I) was examined with regard to myogenic differentiation via signaling pathways which regulate this process. Each factor enhanced Akt and MAPK/ERK (p42/44) phosphorylation and myogenic factor expression levels in a dose‐responsive manner, while combinations of Shh and IGF‐I showed additive effects. Blockage of the IGF‐I effects by neutralizing antibody partially reduced Shh's effects on signaling pathways, suggesting that IGF‐I enhances, but is not essential for Shh effects. Addition of cyclopamine, a Smo inhibitor, reduced Shh‐ and IGF‐I‐induced Akt phosphorylation in a similar manner, implying that Shh affects gain of the IGF‐I signaling pathway. This implication was also examined via a genetic approach. In cultures derived from Smomut (MCre;Smoflox/flox) mice lacking Smo expression specifically in hindlimb muscles, IGF‐I‐induced Akt and p42/44 phosphorylation was significantly reduced compared to IGF‐I's effect on Smocont cells. Moreover, remarkable inhibition of the stimulatory effect of IGF‐I on myogenic differentiation was observed in Smomut cultures, implying that intact Smo is required for IGF‐I effects in myoblasts. Immunoprecipitation assays revealed that tyrosine‐phosphorylated proteins, including the regulatory unit of PI3K (p85), are recruited to Smo in response to Shh. Moreover, IGF‐IR was found to associate with Smo in response to Shh and to IGF‐I, suggesting that Shh and IGF‐I are already integrated at the receptor level, a mechanism by which their signaling pathways interact in augmenting their effects on adult myoblasts. J. Cell. Physiol. 227: 1455–1464, 2012. © 2011 Wiley Periodicals, Inc.
Clozapine impairs insulin action by up‐regulating AKT phosphorylation and Ped/Pea‐15 protein abundance
Authors: Panariello Fabio , Perruolo Giuseppe , Cassese Angela , Giacco Ferdinando , Botta Ginevra , Barbagallo Alessia P.M. , Muscettola Giovanni , Beguinot Francesco , Formisano Pietro , de Bartolomeis Andrea 
Published: May 2011

AbstractClinical and experimental evidence indicates that atypical antipsychotics impair glucose metabolism. We investigated whether clozapine may directly affect insulin action by analyzing insulin signaling in vitro and in vivo. Clozapine reduced insulin‐stimulated glucose uptake in PC12 and in L6 cells, representative models of neuron and skeletal muscle, respectively. Consistently, clozapine reduced insulin effect on insulin receptor (IR) by 40% and on IR substrate‐1 (IRS1) tyrosine phosphorylation by 60%. Insulin‐stimulated Akt phosphorylation was also reduced by about 40%. Moreover, insulin‐dependent phosphorylation of protein kinase C‐ζ (PKC‐ζ) was completely blunted in clozapine‐treated cells. Interestingly, clozapine treatment was accompanied by an insulin‐independent increase of Akt phosphorylation, with no change of IR, IRS1, and PKC‐ζ basal phosphorylation. The cellular abundance of Ped/Pea‐15, an Akt substrate and inducer of insulin resistance, was also increased following clozapine exposure, both in the absence and in the presence of cyclohexymide, a protein synthesis inhibitor. Similar as in cellular models, in the caudate–putamen and in the tibialis muscle of clozapine‐treated C57/BL/KsJ mice, Akt phosphorylation and Ped/Pea‐15 protein levels were increased and PKC‐ζ phosphorylation was decreased. Thus, in these experimental models, clozapine deranged Akt function and up‐regulated Ped/Pea‐15, thereby inhibiting insulin stimulation of PKC‐ζ and of glucose uptake. J. Cell. Physiol. 227: 1485–1492, 2012. © 2011 Wiley Periodicals, Inc.
Antennal sensilla of Apanteles cypris Nixon (Hymenoptera: Braconidae), a larval endoparasitoid of Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae)
Authors: Zhou Hui , Wu Wei‐Jian , Zhnag Zhen‐Fei , Zhnag Yang 
Published: May 2011

AbstractApanteles cypris is an endoparasitoid of rice pest Cnaphalocrocis medinalis. To better understand its host location mechanism, we examined the external morphology of antennal sensilla of A. cypris via scanning electron microscopy. The antennae of male and female A. cypris were filiform in shape, which consist of scape, pedicel, and flagellum with 18 antennomeres. Eleven types of sensilla were recorded in both sexes, including two types of chaetica sensilla, trichodea sensilla without pore, basiconica sensilla I with a tip pore, basiconica sensilla II with wall pores, basiconica sensilla III with a mastoid at the tip, coeloconica sensilla with apparent fingerlike projections, campaniform sensilla with a sprout tip pore, clavatea sensilla, smell pore, and placodea sensilla (PLA) with the multiporous cuticular structure. We also compared the morphology, number, and distribution of the sensory receptors between the two sexes. The length and width of the antennae on the males were significantly greater than that of females. In addition, males of A. cypris showed a larger number and a higher density of PLA compared to females. The morphology and structure of these sensilla were compared to that found in other braconid wasps, and their possible functions in host location were discussed. These observations could facilitate future studies on the biology of olfaction in A. cypris. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
Cytotoxicity of fipronil on mice liver cells
Authors: De Oliveira Patrícia Rosa , Bechara Gervásio Henrique , Denardi Sandra Eloisi , Oliveira Rodrigo Juliano , Mathias Maria Izabel Camargo 
Published: May 2011

AbstractIn the present study, mice livers were examined following exposure to different doses of fipronil (15, 25, and 50 mg/kg). Histological and histochemical techniques were used to determine the cytotoxic potential of this compound and to assess the damage it caused to livers. Mice were divided into four groups: control group and groups I, II, and III were exposed to 15, 25, and 50 mg/kg fipronil, respectively. Our findings revealed cytological, morphohistological, and histochemical alterations in liver cells of animals from groups I, II, and III compared to group control animals. These changes included Kupffer‐cell proliferation, hepatocyte hypertrophy, accumulation and distribution of proteins, polysaccharides, lipids, and vacuoles in the cytoplasm of hepatocytes, and congestion of blood vessels. These phenotypes mainly characterize the following: (a) autophagic processes, (b) steatosis, and (c) cell death by necrosis, which demonstrate the damage caused by fipronil on nontarget organisms in artificial conditions. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
A prospective longitudinal study of BK virus infection in 120 Czech renal transplant recipients
Authors: Girmanova Eva , Brabcova Irena , Bandur Stepan , Hribova Petra , Skibova Jelena , Viklicky Ondrej 
Published: May 2011

AbstractPolyomavirus BK (BKV) is a common human polyomavirus that rarely causes clinical symptoms in immunocompetent individuals. However, BK virus reactivation occurs in 20–40% of kidney transplant patients and 1–10% of cases present with BK virus‐associated nephropathy (BKVN) and reduced kidney allograft survival. In this study, 120 consecutive renal allograft recipients were monitored for BK virus replication by real–time PCR (qPCR) in the blood and urine during the first year post‐transplantation and risk factors for BK viremia, viruria, and polyoma BKV‐associated nephropathy were evaluated. Receiver operating characteristic curve analysis was used to determine the cutoff points for assessing the risk of developing BKVN. In total, 1,243 samples were tested. BK‐DNAuria >107 copies/ml and BK‐DNAemia >104 copies/ml were found in 25.8% and 5% of the samples screened, respectively, during the 12 month follow‐up period. BKVN was confirmed histologically in 3/120 patients and viremic patients were treated with dialysis for longer time periods and had higher levels of anti‐BKV‐reactive antibodies. Patients with viruria were also treated longer with dialysis and had impaired graft function 12 months post‐transplantation. Patients with sustained viruria exhibited more acute rejection episodes than patients with transient viruria. Using receiver operating characteristic curve analysis, the cutoff point for viremia and viruria was redefined to 103 copies/ml serum for BK viremia and a cutoff point of 6.7 × 107 copies/ml in urine. In conclusion, polyoma BK viremia and viruria are frequent findings in kidney transplant recipients that warrant intensive monitoring as a means of preventing graft rejection. J. Med. Virol. 83:1395–1400, 2011. © 2011 Wiley‐Liss, Inc.
Detection of Merkel cell polyomavirus on environmental surfaces
Authors: Foulongne Vincent , Courgnaud Valérie , Champeau William , Segondy Michel 
Published: May 2011

AbstractThe Merkel cell polyomavirus (MCPyV) is a human virus identified recently which is associated with the Merkel cell carcinoma. This virus is also detected frequently in the skin of healthy individuals. The presence of MCPyV has been investigated on environmental surfaces in contact with human skin. Various surfaces in four laboratories, public places, and individual homes were swabbed. Human DNA and MCPyV DNA were detected in swabs by real‐time PCR. MCPyV DNA levels were measured before and after DNase treatment in a set of 12 MCPyV DNA‐positive samples. A total of 60 environmental surface samples were collected. Fifty‐one (85.0%) were positive for human DNA detection and 45 (75.0%) were positive for MCPyV DNA detection. All samples positive for MCPyV DNA were positive for human DNA detection. After DNase treatment, a 1.3 log decrease in MCPyV DNA level was observed indicating that about 5% of viral DNA is protected from DNase degradation and might be associated with infectious virus. These results indicate that MCPyV DNA may be detected on environmental surfaces in contact with human skin. Detection of viral DNA might reflect the presence of infectious viral particles and transmission from environmental source to humans cannot be ruled out. J. Med. Virol. 83:1435–1439, 2011. © 2011 Wiley‐Liss, Inc.
Prevalence and genotypes of human parechovirus in stool samples from hospitalized children in Shanghai, China, 2008 and 2009
Authors: Zhong Huaqing , Lin Yong , Sun Jiae , Su Liyun , Cao Lingfeng , Yang Yi , Xu Jin 
Published: May 2011

AbstractHuman parechoviruses (HPeVs) are widespread pathogens belonging to the Picornavirus family. The aim of the present study was to assess the prevalence and genetic diversity of HPeV in Shanghai, China, during a HPeV screening program in 2008 and 2009. Of 300 stool samples from children under the age of 5 years with acute diarrhea seen at Children's Hospital, Fudan University, Shanghai, China, 165 (55%) were HPeV‐positive. The median age of infected children was 3 months. The prevalence of HPeV was high (57%) in infants up to 2 years old but dropped to 30.4% in children between 2 and 5 years old. The prevalence did not differ by sex. Infections were present throughout the year but peaked in July and August. The most predominant genotype was HPeV1. Of the 139 strains, 4 were found in 9 samples: HPeV4 (n = 4), HPeV5 (n = 1), HPeV6 (n = 1), and HPeV8 (n = 3). This study provided useful data on the epidemiology of HPeV infection by documenting the distribution of genotypes, age of infection, and seasonal patterns in Shanghai, China. J. Med. Virol. 83:1428–1434, 2011. © 2011 Wiley‐Liss, Inc.
Activity‐dependent γ‐aminobutyric acid release controls brain cortical tissue slice metabolism
Authors: Nasrallah Fatima A. , Balcar Vladimir J. , Rae Caroline D. 
Published: May 2011

AbstractVigabatrin (γ‐vinyl‐GABA) is an irreversible inhibitor of the enzyme γ‐aminobutyric acid (GABA) transaminase. It has been shown to increase levels of GABA in brain and result in increased release of GABA from nonsynaptic sources following activation. Here, we use a guinea pig cortical tissue slice model to identify the metabolic sequelae of vigabatrin when incubated with tissue slices alone or when the tissue slices were activated by ligands with targeted activating mechanisms. We show that incubation of slices with AMPA, the group II metabotropic glutamate antagonist EGLU [(2S)‐α‐ethylglutamic acid], or the GABABR antagonist CGP 52432 in the presence of vigabatrin produces very similar metabolic profiles, consistent with the large‐scale turning off of metabolic activity. This effect is blocked by the GABAArho antagonist TPMPA [(1,2,5,6‐tetrahydropyridin‐4‐yl)methylphosphinic acid]. Taken together, these results suggest that GABA, released following activation, acts on extrasynaptic receptors consistent with GABAArho and that these receptors act as a kind of “master switch” that is capable of turning off a range of differently induced activities. © 2011 Wiley‐Liss, Inc.
Activation of stress kinases in the brain of mucopolysaccharidosis IIIB mice
Authors: Cecere Francesca , Di Domenico Carmela , Di Napoli Daniele , Boscia Francesca , Di Natale Paola 
Published: May 2011

AbstractThe accumulation of heparan sulfate (HS) in lysosomes is the primary consequence of the enzyme defect (α‐N‐acetylglucosaminidase) in mucopolysaccharidosis type IIIB. This accumulation triggers a cascade of pathological events that progressively leads to CNS pathology. Here we examined the activation of the three major stress kinases in the neuronal tissue of a murine model of the disease. ERK1/2 was significantly higher in the cortex of 1–2‐month‐old affected animals compared with wild‐type (Wt) littermates. Similarly, ERK1/2 was stimulated in neurons cultured from MPS IIIB mice. SAPK/JNK was also found to be activated in the cortex of 1–2‐month‐old affected animals compared with Wt subjects, and the same was found for cultured neurons. In contrast, the active form of p38MAPK was lower in the cortex of 1‐month‐old MPS IIIB mice compared with Wt animals, but no significant difference was found between the two p38MAPK analyzed in normal and affected neurons cultured in vitro. These data indicate the possible involvement of MAPK dysregulation in the early stage of MPS IIIB brain disease. © 2011 Wiley‐Liss, Inc.
Cardioembolic stroke prompting diagnosis of LMNA‐associated Emery–Dreifuss muscular dystrophy
Authors: Redondo‐Vergé Luis , Yaou Rabah Ben , Fernández‐Recio María , Dinca Luminita , Richard Pascale , Bonne Gisèle 
Published: May 2011

AbstractThe diagnosis of Emery–Dreifuss muscular dystrophy (EDMD) is suggested by the combination of musculoskeletal weakness and wasting, joint contractures, and cardiac disease. Herein we report a patient in whom an ischemic stroke prompted the diagnosis of EDMD. A mutation in the LMNA gene (c.266G>T, p.Arg89Leu) was found. It had been reported previously exclusively with isolated cardiac disease, thus reinforcing the high phenotypic heterogeneity of laminopathies. Muscle Nerve, 2011
Reproducibility of sensory nerve conduction studies of the sural nerve using ultrasound‐guided needle positioning
Authors: Scheidegger Olivier , Küffer Alexander F. , Kamm Christian P. , Rösler Kai M. 
Published: May 2011

AbstractIntroduction:In this study we sought to evaluate the reproducibility of sensory nerve conduction studies (NCS) using ultrasound‐guided needle positioning (USNP).Methods:Orthodromic NCS of the sural nerve using needle electrodes with USNP as well as surface electrodes were conducted twice in 20 healthy volunteers.Results:The mean sensory nerve action potential (SNAP) amplitude in the initial examination was 39.5 μV using needle electrodes with USNP, and 12.5 μV using surface electrodes (P < 0.0001). The mean SNAP amplitude in the follow‐up examination was 39.2 μV using needle electrodes with USNP, and 12.4 μV using surface electrodes (P < 0.0001). The mean intraindividual change in SNAP amplitude (test–retest) was 21.2% using needle electrodes with USNP, and 24.8% using surface electrodes (P = 0.6).Conclusions:Sensory NCS of the sural nerve using needle electrodes with USNP have reliable test–retest reproducibility and yield greater SNAP amplitudes than sensory NCS using surface electrodes. Muscle Nerve 2011
Synthesis and specific influenza A virus‐adsorptive functionality of alkyl curdlan sulfate‐coated membrane filter
Authors: Muschin Tegshi , Han Shuqin , Kanamoto Taisei , Nakashima Hideki , Yoshida Takashi 
Published: May 2011

AbstractTo develop a biomaterial with an influenza virus‐adsorptive functionality, an alkyl curdlan sulfate was prepared by ionic interaction between a positively charged didodecyldimethyl ammonium bromide and a negatively charged sulfate group of curdlan sulfate, which has potent anti‐HIV activity, and then it was coated on a membrane filter with a 1‐μm pore size by hydrophobic interaction with the long alkyl groups in the curdlan sulfate. The alkyl curdlan sulfate with the degree of alkylation (DOA) of 0.03 (one didodecyldimethyl group/12 sugar residues with 36 hydroxyl or sulfate groups) showed potent anti‐HIV activity in a 50% effective concentration (EC50) as low as 0.87 μg/mL (standard curdlan sulfate EC50 = 0.3 μg/mL), and the activity decreased with increasing DOA. A DOA higher than 0.1 (one didodecyldimethyl group/three sugar residues with nine hydroxyl or sulfate groups) gave no anti‐HIV activity. Although both curdlan sulfate and alkyl curdlan sulfates did not inhibited infection of Madin‐Darby canine kidney cells by influenza viruses, the alkyl curdlan sulfate‐coated membrane filter was found to have a specific adsorptive functionality for influenza A virus in vitro. When 1.6 mg of the alkyl curdlan sulfate with the DOA of 0.03 was coated on a membrane filter (φ13 mm; pore size, 1 μm), three stacked alkyl curdlan sulfate‐coated membrane filters dramatically decreased hemagglutination to 1/4–1/32. However, the membrane filter did not effectively remove on influenza B viruses, and thus a membrane filter without alkyl curdlan sulfate was not effective against influenza viruses. These results can therefore be presumed to demonstrate that the alkyl curdlan sulfate‐coated membrane filter removed influenza A viruses by adsorption between the negatively charged sulfate groups and the positively charged envelope protein of the virus. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011