bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rare PIK3CA hotspot mutations in carcinomas of the biliary tract
Authors: Riener Marc‐Oliver , Bawohl Marion , Clavien Pierre‐Alain , Jochum Wolfram 
Published: January 2008

AbstractSomatic mutations of the PIK3CA gene, which encodes the p110α catalytic subunit of phosphatidylinositol 3‐kinase (PI3K), are frequent in various cancer types. The majority of mutations cluster at hotspots within exons 9 and 20, which encode the helical and kinase domains of p110α. PIK3CA mutations in bile duct and gallbladder carcinomas have not been reported yet. In this study, we analysed 118 carcinomas of the biliary tract and the liver (45 intra‐ and extrahepatic cholangiocarcinomas (CCA), 23 gallbladder carcinomas, 50 hepatocellular carcinomas) for PIK3CA hotspot mutations using polymerase chain reaction and direct DNA sequencing. PIK3CA missense mutations were found in one of 11 intrahepatic CCA (E545K, 9%), one of 23 gallbladder carcinomas (E542K, 4%), and one of 50 hepatocellular carcinomas (H1047R, 2%). All three mutations represent hotspot mutations, which also occur in other cancer types. PI3K pathway activation in hepato‐biliary carcinomas was analyzed using immunohistochemistry for the downstream targets eIF4‐E and phosphorylated 4E‐BP1 on tissue microarrays. eIF4‐E expression was found in 3/13 intrahepatic CCA (23%), 9/38 extrahepatic CCA (24%), 12/34 gallbladder carcinomas (35%), and 9/61 hepatocellular carcinomas (15%). 4E‐BP1 phosphorylation was observed in 1/13 intrahepatic CCA (8%), 8/38 extrahepatic CCA (21%), 15/34 gallbladder carcinomas (44%), and 16/61 hepatocellular carcinomas (26%). These results indicate that somatic PIK3CA mutations contribute to the frequent activation of the PI3K/AKT pathway in carcinomas of the biliary tract and liver. © 2008 Wiley‐Liss, Inc.
Fronto‐temporal alterations within the first 200 ms during an attentional task distinguish major depression, non‐clinical participants with depressed mood and healthy controls: A potential biomarker?
Authors: Kemp Andrew. H. , Hopkinson Patrick J. , Hermens Daniel F. , Rowe Donald L. , Sumich Alexander L. , Clark C. Richard , Drinkenburg Wilhelmus , Abdi Nadia , Penrose Rebecca , McFarlane Alexander , Boyce Philip , Gordon Evian , Williams Leanne M. 
Published: January 2008

AbstractAttentional impairment in depression is a cardinal feature of depression and has been proposed as a candidate endophenotype for major depressive disorder. Event‐related potentials (ERPs) elicited by oddball signal detection tasks provide objective markers of selective stimulus processing, and are pertinent endophenotypic markers for depression. While previous studies have sought to determine objective markers for attentional impairment in depression, evidence is inconsistent and may involve heterogeneity in relatively small samples. Here, we brought together oddball ERP recording with source localization of neural correlates of selective attention in outpatients with major depressive disorder (MDD; n = 78) and participants with depressed mood (PDM; n = 127) relative to healthy controls (CTL; n = 116). The key finding was a dimensional exaggeration of the P200 (140–270 ms) to both target (signal) and non‐target (noise) stimuli, most pronounced in MDD, followed by PDM, relative to CTL. This exaggeration was coupled with slower and more variable response times, suggesting that neural systems are attempting to compensate for a difficulty in discriminating signal from noise. P200 alterations were localised to limbic (hippocampal), temporal and ventral prefrontal regions, key components of the signal detection network. A subsequent reduction and delay in the P300 was also revealed for MDD indicating that the pronounced lack of discrimination in clinical depression may also lead to impaired stimulus evaluation. This P200 increase in depression could provide a potential mechanism for the attentional impairment frequently observed in depression and consequent alterations in the P300 may differentiate clinically significant depression. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Synthesis, characterization, and in vitro cell culture viability of degradable poly(N‐isopropylacrylamide‐co‐5,6‐benzo‐2‐methylene‐1,3‐dioxepane)‐based polymers and crosslinked gels
Authors: Siegwart Daniel J. , Bencherif Sidi A. , Srinivasan Abiraman , Hollinger Jeffrey O. , Matyjaszewski Krzysztof 
Published: January 2008

AbstractPoly(N‐isopropylacrylamide‐co‐5,6‐benzo‐2‐methylene‐1,3‐dioxepane) (poly(NIPAAm‐co‐BMDO)) was synthesized by atom transfer radical polymerization (ATRP) and reversible addition‐fragmentation chain transfer (RAFT) polymerization. Using UV–vis spectroscopy, the lower critical solution temperature (LCST) of poly(NIPAAm) and poly(NIPAAm‐co‐BMDO) copolymers were measured, varying with respect to the amount of incorporated BMDO. This material is degradable and possesses a LCST above room temperature and below body temperature, making it a potential candidate for use as an injectable tissue engineering scaffold to enhance fracture repair. ATRP and RAFT enabled preparation of polymers with control over molecular weight up to Mn = 50,000 g/mol and Mw/Mn < 1.2. Degradation studies were performed in basic solution and in complete Dulbecco's modified Eagle medium. The cytotoxicity of the material and its degradation products were analyzed by in vitro cell culture analyses, including cytotoxicity live/dead and CyQUANT cell proliferation assays. Crosslinked scaffolds with degradable units within the polymer backbone and at the crosslinking sites were prepared using an ester‐containing diacrylate crosslinker. Furthermore, incorporation of a GRGDS peptide sequence improved cell attachment to the gels. Controlled/living radical polymerization techniques allow for precise control over macromolecular structure and are poised to become powerful tools for tissue engineering scaffold synthesis. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Effect of mouse VEGF164 on the viability of hydroxyethyl methacrylate–methyl methacrylate‐microencapsulated cells in vivo: Bioluminescence imaging
Authors: Cheng Dangxiao , Lo Chuen , Sefton Michael V. 
Published: January 2008

AbstractBioluminescent imaging was used to track the viability of luciferase transfected L929 cells in poly(hydroxyethyl methacrylate‐co‐methyl methacrylate) (HEMA‐MMA) microcapsules. Bioluminescence, as determined by Xenogen imaging after addition of luciferin to microcapsules in vitro, increased with time, consistent with an increase in cell number. Capsules were suspended in Matrigel and injected subcutaneously. The bioluminesence in vivo increased over the first 3 weeks and then decreased, both with and without the delivery of mVEGF164 (1.2 ng/24 h/200 microcapsules in vitro); VEGF delivery was from microencapsulated doubly transfected cells (both luciferase and mVEGF164). VEGF delivery was sufficient to generate a greater number of vascular structures, but this did not result in the expected increase in microencapsulated cell viability. Interestingly, the number of vessels at day 28 was less than at day 21, consistent with what would be an expected reduction in VEGF secretion when cell viability is lost. The results presented here do not support the hypothesis that transfection of microencapsulated cells with VEGF is sufficient to correct the oxygen transport limitation, at least with this type of tissue engineering construct. On the other hand, bioluminescent imaging proved to be a useful method of monitoring microencapsulated cell viability over many weeks in vivo. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Synovial cell culture and tissue engineering of a tendon synovial cell biomembrane
Authors: Ozturk Akif Muhtar , Yam Andrew , Chin Song In , Heong Tan Soo , Helvacioglu Fatma , Tan Agnes 
Published: January 2008

AbstractRestrictive adhesions are a common complication of tendon injury and repair in the hand, resulting in severe dysfunction. Creating a barrier between the repair sites and surrounding tissue layers may prevent adhesions. We present the first stage in the process of developing a synovial biomembrane for this purpose. Synovial cells harvested from the Achilles tendon sheath and the knee joint of a Wistar albino rat were cultured for 2 weeks in culture medium, and then impregnated into a collagen type 1 matrix for another 2 weeks. Cells originating from both tendon and synovium demonstrated cell growth and layer formation on the surfaces of the matrix 2 weeks after impregnation. Alcian blue staining using Scott's method demonstrated the presence of acidic mucopolysaccharide, indicating hyaluronic acid (HA) production. This provides indirect evidence of functioning synovial cells on the membrane. It is possible to culture synovial cells and engineer a synoviocyte–collagen membrane that synthesizes endogenous HA. Application of this biomembrane to tendon repair sites may help to prevent adhesions after tendon repairs. Evaluation of this method on in vivo models is required. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Nano hydroxyapatite structures influence early bone formation
Authors: Meirelles Luiz , Arvidsson Anna , Andersson Martin , Kjellin Per , Albrektsson Tomas , Wennerberg Ann 
Published: January 2008

AbstractIn a study model that aims to evaluate the effect of nanotopography on bone formation, micrometer structures known to alter bone formation, should be removed. Electropolished titanium implants were prepared to obtain a surface topography in the absence of micro structures, thereafter the implants were divided in two groups. The test group was modified with nanosize hydroxyapatite particles; the other group was left uncoated and served as control for the experiment. Topographical evaluation demonstrated increased nanoroughness parameters for the nano‐HA implant and higher surface porosity compared to the control implant. The detected features had increased size and diameter equivalent to the nano‐HA crystals present in the solution and the relative frequency of the feature size and diameter was very similar. Furthermore, feature density per μm2 showed a decrease of 13.5% on the nano‐HA implant. Chemical characterization revealed calcium and phosphorous ions on the modified implants, whereas the control implants consisted of pure titanium oxide. Histological evaluation demonstrated significantly increased bone formation to the coated (p < 0.05) compared to uncoated implants after 4 weeks of healing. These findings indicate for the first time that early bone formation is dependent on the nanosize hydroxyapatite features, but we are unaware if we see an isolated effect of the chemistry or of the nanotopography or a combination of both. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Selective binding of carcinoembryonic antigen using imprinted polymeric hydrogels
Authors: Casey Brendan J. , Kofinas Peter 
Published: January 2008

AbstractA poly(allylamine hydrochloride) carcinoembryonic antigen‐imprinted hydrogel was synthesized using a water‐soluble crosslinker, ethylene glycol diglycidyl ether, to investigate its viability for protein recognition. The imprinting factor of the imprinted hydrogel toward carcinoembryonic antigen was found to be ∼5, while the imprinting factor of the imprinted hydrogel toward α‐fetoprotein was determined to be ∼2, suggesting selectivity and specificity toward the template protein. This work lays the foundation for the development of a novel line of imprinted hydrogel systems capable of protein recognition for diagnostic and therapeutic applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
A novel method to prepare water‐dispersible magnetic nanoparticles and their biomedical applications: Magnetic capture probe and specific cellular uptake
Authors: Yu Changjiang , Zhao Jianjun , Guo Yingzhi , Lu Cailing , Ma Xu , Gu Zhongwei 
Published: January 2008

AbstractA novel and simple method to form water‐dispersed magnetic nanoparticles was successfully developed through glucosaminic acid‐surface modification of iron oxide nanoparticles. The resultant glucosaminic acid‐modified magnetic nanoparticles (GA‐MNPs) had not only good uniformity in spherical shape with diameter of about 10–13 nm, but also possessed excellent water‐dispersity and stability. In cell culture experiments, the internalization of GA‐MNPs into different kinds of cells was observed over a 5‐day period. The results indicated that the internalization of GA‐MNPs into mouse macrophage cells and mouse embryonic fibroblast cells was not observed after 40 h of culturing. However, the GA‐MNPs were internalized quickly into cancer cells after just 24 h of culturing. TEM images of the GA‐MNPs uptake in ECA‐109 cells were used to study the internalization mechanisms of GA‐MNPs and their distribution in ECA‐109 cells. Additionally, a water‐dispersed magnetic capture probe was prepared by immobilization of oligonucleotides onto GA‐MNPs, and the probe was used for detection and separation of their complementary oligonucleotides sequence. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 87A: 364–372, 2008
Synthesis and characterization of functionalized biodegradable poly(DL‐lactide‐co‐RS‐β‐malic acid)
Authors: He Bin , Poon Yin Fun , Feng Jie , Chan‐Park Mary B. 
Published: January 2008

AbstractAmorphous poly(DL‐lactide‐co‐RS‐β‐malic acid) (PDLLMAc) was synthesized by hydrogenolysis of poly(DL‐lactide‐co‐RS‐β‐malolactonate) (PDLLMA), which was obtained from the ring‐opening polymerization of DL‐lactide (DLLA) and RS‐β‐benzyl malolactonate (MA) using stannous octoate as the catalyst. The amount of malolactonate (MA) in the feeding dose was varied from 0 to 8.0 mol %. The copolymers were characterized by 1H NMR, FTIR, GPC, and DSC. The tensile properties and water uptake of the copolymers were measured. The protective benzyl groups in PDLLMA were completely removed in hydrogenolysis to produce PDLLMAc. The molecular weight (Mn) of the copolymers decreased with increasing MA content. However, with low feed MA content of 0.6 and 1.0%, high molecular weight PDLLMAc with Mn of 63 and 35 kDa, respectively, were obtained; these copolymers exhibited good tensile yield stress and modulus of 17–23 MPa and 1.1–1.4 GPa, which are comparable to PDLLA homopolymer. The corresponding protected PDLLMA have tensile yield stress/modulus of 2.0–2.4 MPa and 11–42 MPa. The malic acid comonomer in PDLLMAc significantly improves the tensile strength and modulus compared to the protected PDLLMA. Further, the functionalizable PDLLMAc (with 0.6 mol % feed MA) was grafted with bioactive RGD peptide. The culture of primary umbilical artery smooth muscle cells was investigated. Methylthiazoletetrazolium results showed that both the RGD‐ and COOH‐functionalized (0.6 mol %) PDLLMAc copolymers were significantly more biocompatible than the control PDLLA and could potentially be employed as tissue engineering scaffolds. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Back‐regulation of six oxidative stress proteins with grape seed proanthocyanidin extracts in rat diabetic nephropathy
Authors: Li Bao‐Ying , Cheng Mei , Gao Hai‐Qing , Ma Ya‐Bing , Xu Ling , Li Xian‐Hua , Li Xiao‐Li , You Bei‐An 
Published: January 2008

AbstractDiabetic nephropathy (DN) is a major cause of morbidity and mortality in diabetic patients. To prevent the development of this disease and to improve advanced kidney injury, effective therapies directed toward the key molecular target are required. Grape seed proanthocyanidin extracts (GSPE) have been reported to be effective in treating DN, while little is known about the functional protein changes. In this study, we used streptozotocin (STZ) to induce diabetic rats. GSPE (250 mg/kg body weight/day) were administrated to diabetic rats for 24 weeks. Serum glucose, glycated hemoglobin, and advanced glycation end products were determined. Consequently, 2‐D difference gel electrophoresis and mass spectrometry were used to investigate kidney protein profiles among the control, untreated and GSPE treated diabetic rats. Twenty‐five proteins were found either up‐regulated or down‐regulated in the kidneys of untreated diabetic rats. Only nine proteins in the kidneys of diabetic rats were found to be back‐regulated to normal levels after GSPE therapy. These back‐regulated proteins are involved in oxidative stress, glycosylation damage, and amino acids metabolism. Our findings might help to better understanding of the mechanism of DN, and provide novel targets for estimating the effects of GSPE therapy. J. Cell. Biochem. 104: 668–679, 2008. © 2008 Wiley‐Liss, Inc.
Small weight codewords in the LDPC codes arising from linear representations of geometries
Authors: Pepe V. , Storme L. , Van de Voorde G. 
Published: January 2008

AbstractIn this article, we investigate the minimum distance and small weight codewords of the LDPC codes of linear representations, using only geometrical methods. First, we present a new lower bound on the minimum distance and we present a number of cases in which this lower bound is sharp. Then we take a closer look at the cases$T_2^*(\Theta)$and$T_2^*(\Theta)^D$with$\Theta$a hyperoval, henceqeven, and characterize codewords of small weight. When investigating the small weight codewords of$T_2^*(\Theta)^D$, we deal with the case of$\Theta$a regular hyperoval, that is, a conic and its nucleus, separately, since in this case, we have a larger upper bound on the weight for which the results are valid. © 2008 Wiley Periodicals, Inc. J Combin Designs 17: 1–24, 2009
Reversal of myofibroblasts by amniotic membrane stromal extract
Authors: Li Wei , He Hua , Chen Ying‐Ting , Hayashida Yasutaka , Tseng Scheffer C.G. 
Published: January 2008

AbstractMyofibroblasts play an important role in morphogenesis, inflammation, and fibrosis in most tissues. The amniotic membrane stroma can maintain keratocytes in cultures and prevent them from differentiating into myofibroblasts. However, it is unknown whether the AM stroma can also reverse differentiated myofibroblasts. In this study, we found that amniotic membrane stromal cells (AMSCs), which adopted fibroblastic phenotype in vivo, quickly and completely differentiated into myofibroblasts during ex vivo culture in DMEM/FBS on plastic within 2 passages. When cultured on type I collagen, the myofibroblasts maintained their phenotype, however, when these myofibroblasts were re‐seeded onto a cryopreserved amniotic membrane stromal surface, they reversed to the fibroblast phenotype. Moreover, we found that the amniotic membrane stromal extract not only helps maintain primary AMSCs fibroblastic phenotype in vitro, but also can reverse differentiated myofibroblasts back to fibroblasts. This reversal was not coupled with cell proliferation. We concluded that the amniotic membrane stroma contains soluble factors that can regulate the mesenchymal cell differentiation. Further investigation into the identity of these factors and the control mechanisms may unravel a new scar‐reversing strategy. J. Cell. Physiol. 215: 657–664, 2008. © 2008 Wiley‐Liss, Inc.
Cooperation of docosahexaenoic acid and vitamin E in the regulation of UDP‐glucuronosyltransferase mRNA expression
Authors: Caputo Mariella , Eletto Davide , Torino Gaetano , Tecce Mario F. 
Published: January 2008

AbstractDocosahexaenoic acid (DHA) is a well known chemopreventive nutrient within diet formulations, but it may also exert toxic effects on cultured cells, while this is limited when also another relevant nutrient as vitamin E is present. This effect, beside the involvement of the two nutrients in oxidative processes, likely affects the expression of specific genes. To obtain information on combined activities of DHA and vitamin E on some gene products previously resulted to be in vivo regulated from dietary unsaturated fats, the effect of the two nutrients was evaluated in human cell line HepG2. Independently, DHA and vitamin E resulted to affect only slightly UDP‐glucuronosyltransferase 1A1 (UGT1A1) mRNA expression. Nevertheless, their combination produced a considerable reduction of this mRNA. DHA also downregulated stearoyl‐CoA desaturase (SCD) and sterol regulatory element binding protein (SREBP‐1) expression, while vitamin E did not affect these products. However, their combination abolished the downregulation of SCD but did not affect that of SREBP‐1. Therefore the effect of the two nutrients is related to specific gene regulation processes resulting in a cooperation which might be related to their physiological effects as dietary components. J. Cell. Physiol. 215: 765–770, 2008. © 2008 Wiley‐Liss, Inc.
Platelet‐rich plasma enhances the initial mobilization of circulation‐derived cells for tendon healing
Authors: Kajikawa Yoshiteru , Morihara Toru , Sakamoto Hirotaka , Matsuda Ken‐ichi , Oshima Yasushi , Yoshida Atsuhiko , Nagae Masateru , Arai Yuji , Kawata Mitsuhiro , Kubo Toshikazu 
Published: January 2008

AbstractCirculation‐derived cells play a crucial role in the healing processes of tissue. In early phases of tendon healing processes, circulation‐derived cells temporarily exist in the wounded area to initiate the healing process and decrease in number with time. We assumed that a delay of time‐dependent decrease in circulation‐derived cells could improve the healing of tendons. In this study, we injected platelet‐rich plasma (PRP) containing various kinds of growth factors into the wounded area of the patellar tendon, and compared the effects on activation of circulation‐derived cells and enhancement of tendon healing with a control group (no PRP injection). To follow the circulation‐derived cells, we used a green fluorescent protein (GFP) chimeric rat expressing GFP in the circulating cells and bone marrow cells. In the PRP group, the numbers of GFP‐positive cells and heat‐shock protein (HSP47; collagen‐specific molecular chaperone)‐positive cells were significantly higher than in the control group at 3 and 7 days after injury. At the same time, the immunoreactivity for types I and III collagen was higher in the PRP group than in the control group at early phase of tendon healing. These findings suggest that locally injected PRP is useful as an activator of circulation‐derived cells for enhancement of the initial tendon healing process. J. Cell. Physiol. 215: 837–845, 2008. © 2008 Wiley‐Liss, Inc.
Radioguided occult lesion localization (ROLL) versus wire‐guided lumpectomy for non‐palpable breast lesions: A randomized prospective evaluation
Authors: Medina‐Franco Heriberto , Abarca‐Pérez Leonardo , García‐Alvarez Miriam N. , Ulloa‐Gómez José L. , Romero‐Trejo Cecilia , Sepúlveda‐Méndez Jesús 
Published: January 2008

AbstractBackgroundIt is important to optimize the localization technique for non‐palpable breast lesions.MethodsOne hundred consecutive women with non‐palpable breast lesions were randomized to radioguided occult lesion localization (ROLL) or wire localization (WL). For ROLL technique 99mTc‐labeled particles of human serum albumin were injected under breast‐imaging control. Localization of the lesion was done in the operating room with the aid of a gamma‐probe. All lesions were identified in an X‐ray control of the surgical specimen. Categorical variables were analyzed with the Chi‐square method. Significance was considered at P < 0.05.ResultsAll procedures were performed on the same day of excision, on ambulatory basis. Both techniques resulted in 100% retrieval of the lesions. Localization time was reduced with ROLL (P < 0.001). Clear margins were achieved in 88.9% ROLLs and 62.5% WLs (P < 0.05) reducing the requirement of re‐excision. There were significant differences in the subjective ease of the procedures in favor of ROLL technique as rated by surgeons and radiologists.ConclusionsROLL technique is as effective as WL for excision of non‐palpable breast lesions, reduce localization time and probably the incidence of pathologically involved margins of excision. ROLL appears to improve the learning curve for surgical residents and cosmesis. ROLL is an attractive alternative to WL. J. Surg. Oncol. 2008;97:108–111. © 2008 Wiley‐Liss, Inc.