bluuebunny/crossref_metadata_2025_split huggingface dataset:
IAPS and ubiquitylation
Authors: Feltham Rebecca , Khan Nufail , Silke John 
Published: February 2012

AbstractThe Inhibitor of apoptosis (IAP) proteins are key negative regulators of cell death, whose amplification has been correlated with tumor progression. Due to the presence of a RING domain, IAP proteins are classed as ubiquitin ligases and regulate cell survival by orchestrating a variety of ubiquitin modifications. Ubiquitin protein modification is fundamental in cell signaling and different ubiquitin modifications may label proteins for destruction, relocalization or provide a recruitment platform for ubiquitin binding proteins. Ubiquitin performs a myriad of different functions because it can be conjugated to a large range of target proteins through numerous different types of ubiquitin linkages. Despite the fact that ubiquitin is extremely versatile, the E3s such as the IAPs provide an important level of control due to their specificity for certain substrates. Several recent reviews have discussed the role of IAPs in regulating immune signaling so we have therefore focused our review on the interplay between IAPs and ubiquitin and discussed the importance of this relationship for the regulation of themselves, specific substrates and various cell death and survival signaling pathways. © 2012 IUBMB Life, 2012
Confocal Raman microspectroscopic study of folate receptor‐targeted delivery of 6‐mercaptopurine‐embedded gold nanoparticles in a single cell
Authors: Park Jin , Jeon Won Il , Lee So Yeong , Ock Kwang‐Su , Seo Ji Hye , Park Jinho , Ganbold Erdene‐Ochir , Cho Keunchang , Song Nam Woong , Joo Sang‐Woo 
Published: February 2012

AbstractWe investigate the cellular uptake behaviors and efficacy of folate‐coated gold nanoparticles (AuNPs) for the targeted drug delivery system in human cancer cells. Folate‐conjugated AuNPs embedded with a purine analogue cancer drug of 6‐mercaptopurine (6MP) were assembled via a 1‐ethyl‐3‐[3‐dimethylaminopropyl] carbodiimide hydrochloride (EDC) coupling reaction between the amino group of 4‐aminobenzenethiol (ABT) and the carboxyl group of folic acid. The assembly of folate and 6MP on AuNPs has been examined by absorption spectroscopy, transmission electron microscopy (TEM), and confocal Raman spectroscopy. The internalization of the conjugated AuNPs inside the folate receptor‐positive HeLa and KB cells was checked by TEM and dark‐field microscopy (DFM) combined with label‐free confocal spectroscopy over the depth variablezat a micrometer resolution. DFM live cell imaging of folate‐conjugated AuNPs in HeLa cells indicated that the targeted AuNPs appeared to attach on the cell surfaces and enter into the cell with an hour. The cell viability was also compared to estimate the efficacy of folate‐conjugated AuNP delivery systems. Folate receptor‐targeted AuNP systems appeared to decrease cancer cell viability bothin vitroandin vivomore than did the use of the 6MP‐coated AuNPs drug without any targeting systems. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Increased osteoblast adhesion on physically optimized KRSR modified calcium aluminate
Authors: Palchesko Rachelle N. , Romeo Jared D. , McGowan Kenneth A. , Gawalt Ellen S. 
Published: February 2012

AbstractCalcium aluminate (CA) is a porous biocompatible material easily cast at room temperature. Through this casting process, the average surface pore size of CA was varied from an average of 100 to 290 microns. The optimal surface pore size of the hydrated CA for cell viability was determined to be 100 microns. Further, a three step‐solution deposition technique was developed to covalently immobilize cell adhesion peptides, RGD, and KRSR to the CA surface. Cell adhesion for 1‐, 4‐, and 7‐day time periods was tested with primary osteoblasts and NIH 3T3 fibroblasts. Both peptides were found to increase fibroblast adhesion to the CA surface. However, only KRSR increased osteoblast adhesion to the surface of the CA, which may aid in bone formation after implantation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
High thrombin concentrations in fibrin sealants induce apoptosis in human keratinocytes
Authors: Gugerell Alfred , Schossleitner Klaudia , Wolbank Susanne , Nürnberger Sylvia , Redl Heinz , Gulle Heinz , Goppelt Andreas , Bittner Michaela , Pasteiner Waltraud 
Published: February 2012

AbstractOver the last century many studies have been performed to assess the impact of fibrin sealant (FS) components on cells. Because of the noncovalent bonding of thrombin to fibrin during fibrin clot formation, we wanted to further evaluate the impact of fibrin bound thrombin on cell viability. Initially, we quantified the activity of thrombin in three different, commercially available FS. This information was used to prepare fibrin clots covering a range of thrombin concentrations from 4 to 820 IU mL−1, but which were identical with respect to all other constituents. Although these fibrin clots did not differ in their three‐dimensional structure, clots prepared with highly concentrated thrombin (820 IU mL−1) failed to support adhesion and spreading of primary human keratinocytes (NHEK). The number of attached cells was also significantly reduced on high thrombin activity clots. We hypothesized that these observations are not only the consequence of decreased proliferation but of apoptotic mechanisms, since the expression of cleaved caspase 3 and 7 was strongly enhanced on fibrin clots with high thrombin activity. This was accompanied by an induction of expression of Trail‐R2 which is a receptor known to mediate apoptosis signals. Blocking of thrombin activity by hirudin led to an improvement of cell morphology and to an increase in number of attached cells. In addition, the induction of caspase 3 and 7 was also reduced. Thus, here we report for the first time that fibrin bound thrombin does not only decrease proliferation (as already published by others), it also does induce NHEK apoptosis when present at high concentrations. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Covalent vectored binding of functional proteins by bifunctional crosslinking at silicone interfaces
Authors: Steiert Andreas , Reimers Kerstin , Burke William , Zapf Antonia , Vogt Peter 
Published: February 2012

AbstractIn the daily clinical routine, numerous synthetic medical devices are implanted in the human body, either temporarily or permanently. The synthetic material most often implanted is polydimethylsiloxane (silicone). Numerous studies have demonstrated that silicone is encompassed in a connective tissue capsule by the body, preventing integration into the surrounding tissue. This can result in complications. The aim of our study was to develop a simple procedure to functionalize the silicone surface, thereby positively affecting the material's biocompatibility. By combining a silanization with the use of ester activation, a reactive amino group is generated, which can bind any free carboxyl group. Directional crosslinking of a near‐infrared‐conjugated fluorophore antibody to the activated silicone surface could be demonstrated on a dose‐dependent basis. The redox reaction at a silicone surface coated with an HRP‐conjugated antibody caused by the addition of NBT/BCIP could be shown. Covering the silicone discs with an anti‐FAS‐antibody coating followed by a coincubation with FAS‐sensitive T‐cells allowed highly significant detection of caspase‐3. In summary, our crosslinking procedure enables the stable binding of proteins without the loss of biological function. Through this process, silicones could be endowed with new functions which could improve their biocompatibility. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Cutaneous and inflammatory response to long‐term percutaneous implants of sphere‐templated porous/solid poly(HEMA) and silicone in mice
Authors: Fleckman Philip , Usui Marcia , Zhao Ge , Underwood Robert , Maginness Max , Marshall Andrew , Glaister Christine , Ratner Buddy , Olerud John 
Published: February 2012

AbstractThis study investigates mouse cutaneous responses to long‐term percutaneously implanted rods surrounded by sphere‐templated porous biomaterials engineered to mimic medical devices surrounded by a porous cuff. We hypothesized that keratinocytes would migrate through the pores and stop, permigrate, or marsupialize along the porous/solid interface. Porous/solid‐core poly(2‐hydroxyethyl methacrylate) [poly(HEMA)] and silicone rods were implanted in mice for 14 days, and for 1, 3, and 6 months. Implants with surrounding tissue were analyzed (immuno)histochemically by light microscopy. Poly(HEMA)/skin implants yielded better morphologic data than silicone implants. Keratinocytes at the poly(HEMA) interface migrated in two different directions. “Ventral” keratinocytes contiguous with the dermal‐epidermal junction migrated into the outermost pores, forming an integrated collar surrounding the rods. “Dorsal” keratinocytes appearing to emanate from the differentiated epithelial layer, extended upward along and into the exterior portion of the rod, forming an integrated sheath. Leukocytes persisted in poly(HEMA) and silicone pores for the duration of the study. Vascular and collagen networks within the poly(HEMA) pores matured as a function of time up to 3‐months implantation. Nerves were not observed within the pores. Poly(HEMA) underwent morphological changes by 6 months of implantation. Marsupialization, foreign body encapsulation, and infection were not observed in any implants. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Observation of dimethylaminoethyl methacrylate–myoglobin binding reaction using laser spray mass spectrometry
Authors: Takamizawa Atsushi , Mishina Kayoko , Hiraoka Kenzo 
Published: February 2012

ABSTRACTCovalent bonds are often created by a reaction between chemicals and protein before causing various adverse effects in a cell. Dimethylaminoethyl methacrylate (DMAEMA), which has moderate toxicity, causes skin inflammation and throat irritation. For this study, we investigated a reaction mechanism between myoglobin and (DMAEMA) using a new analytical tool developed at our laboratory: laser spray mass spectrometry technique. It was found that initially DMAEMA was added to the amino group of protein by the Michael addition mechanism; the added DMAEMA was hydrolyzed to methacrylic acid using an autocatalytic system. The results of this study indicate the feasibility of the laser spray technique in analyses of reaction dynamics. Copyright © 2012 John Wiley & Sons, Ltd.
Formation of oligomeric alkenylperoxides during the oxidation of unsaturated fatty acids: an electrospray ionization tandem mass spectrometry study
Authors: Villaverde Juan José , Santos Sónia A. O. , Maciel Elisabete , Simões Mário M. Q. , Neto Carlos Pascoal , Domingues M. Rosário M. , Silvestre Armando J. D. 
Published: February 2012

This study reports the identification of oligomeric alkenylperoxides by electrospray ionization mass spectrometry (ESI‐MS) and tandem mass spectrometry (ESI‐MS2), during the oxidation of oleic, linoleic and linolenic acids with Fenton's (Fe2+/H2O2) and Fe2+/O2 systems. The reactions were followed by ferrous oxidation‐xylenol orange method together with GC‐MS and GC‐FID, allowing to observe that both oxidation systems are different in terms of hydroperoxide evolution, probably due to the presence of different intermediate reactive species: perferryl ion and OH· radical responsible for the decomposition of lipid hydroperoxides and formation of new compounds.The analysis of ESI‐MS in the negative mode, obtained after oxidation of each fatty acid, confirmed the presence of the monomeric oxidation products together with other compounds at high mass region above m/z 550. These new ions were attributed to oligomeric structures, identified by the fragmentation pathways observed in the tandem mass spectra. Copyright © 2012 John Wiley & Sons, Ltd.
Assessment of mineral phosphate‐solubilizing properties and molecular characterization of zinc‐tolerant bacteria
Authors: Misra Neha , Gupta Garima , Jha Prabhat N. 
Published: February 2012

AbstractPlant growth‐promoting bacteria with the ability to tolerate heavy metals have importance both in sustainable agriculture and phytoremediation. The present study reports on the isolation and characterization of mineral phosphate‐solubilizing (MPS) bacteria associated with the Achyranthes aspera L. plant (prickly chaff, flower plant). Out of 35 bacterial isolates, 6 isolates, namely RS7, RP23, EPR1, RS5, RP11 and RP19, with high MPS activity were selected and subjected to the assessment of MPS activity under various stress conditions, viz. ZnSO4 (0.30–1.5 M), NaCl and temperature. MPS activity by the selected isolates was observed at concentrations of as high as >1.2 M ZnSO4. Significant improvement in plant growth was observed on bacterization of seeds (pearl millet) with all of the six selected isolates. Plant growth was measured in terms of root length, shoot length, fresh weight and % increase in root biomass. The molecular diversity among the phosphate‐solubilizing bacteria was studied employing enterobacterial repetitive intergenic sequence‐PCR (ERIC‐PCR). Representative strains from each ERIC type were identified, on the basis of a partial sequence of the 16S rRNA gene, as members of the genera Pseudomonas, Citrobacter, Acinetobacter, Serratia, and Enterobacter. Among all the isolates, RP19 was the best in terms of phosphate‐solubizing activity and its response to various stresses. The ability of RP19 and other isolates to exhibit MPS activity at high ZnSO4 concentrations suggests their potential as efficient biofertilizer for growing plants in metal (ZnSO4)‐contaminated soil. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identification of a novel agarolytic γ ‐Proteobacterium Microbulbifer maritimus and characterization of its agarase
Authors: Vijayaraghavan R. , Rajendran S. 
Published: February 2012

AbstractThe phenotypic and agar degrading features of an unidentified marine bacteria was investigated. The strain was Gram‐negative, obligatory aerobic and non motile. On the basis of several morphological features and a phylogenetic analysis of the genes coding for the 16S rDNA, this strain was identified as Microbulbifer maritimus. On solid agar medium, this isolate produced extracellular agarase which causes agar liquefaction around the colonies. An extracellular agarase was purified by ammonium sulfate precipitation, gel filtration and ion‐exchange chromatography on DEAE‐cellulose. The purified protein migrated as a single band on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and it had a molecular mass of 75.2 kDa. The enzyme exhibited maximal activity at pH 7.5. The kinetic parameters of the enzyme were Km = 3 ± 0.19 mM, Kcat = 160 ± 10 S–1 and Kcat/Km = 53 ± 10 S–1 · mM–1. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ubiquitous Acinetobacter species as beneficial commensals but gradually being emboldened with antibiotic resistance genes
Authors: Adegoke Anthony A. , Mvuyo Tom , Okoh Anthony I. 
Published: February 2012

AbstractAcinetobacter spp. are ubiquitous obligate aerobic bacteria which occur mostly as commensals on the skin, and in soil, water and plants' rhizosphere. Though the species in this genus have been implicated as aetiologies in some nosocomial infections, their versatility covers biodegradation or dissolution leading to bioremediation; catalysis leading to synthesis of high molecular weight, life sustaining polymers; and as growth enhancers in agriculture. The challenge of antibiotic resistance and their mediatory genes is a cause for concern but should not deter the beneficial application of the bacteria especially in the synthesis of novel compounds that would be of relevance in overcoming some global ecological challenges. This review addresses important beneficial attributes of Acinetobacter species as well as gives some insight into emerging trends in their resistance to antibiotics. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Production of laccase from Trametes trogii TEM H2: a newly isolated white‐rot fungus by air sampling
Authors: Kocyigit Ali , Pazarbasi M. Baris , Yasa Ihsan , Ozdemir Guven , Karaboz Ismail 
Published: February 2012

AbstractThis work represents the first report of isolation of potential laccase producers by air sampling using media supplemented with 2,2‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonate) and guaiacol for laccase production and secretion indicators. Nine fungal isolates showed positive reactions with 2,2‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonate) and guaiacol. The isolate named TEM H2 exhibited the largest and intensive oxidation zones with 2,2‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonate) (85 mm) and guaiacol (66 mm) and therefore it was selected for detailed investigations. The strain was identified as Trametes trogii TEM H2 due to the morphological characteristics and the comparison of internal transcribed spacer ribosomal DNA gene sequences. The laccase production was screened in different liquid cultures. The best laccase production medium was determined as soluble starch yeast extract medium in which laccase production was reached to a maximum level (989.6 U l–1) on the 8th day of cultivation. Effects of different initial pH values on laccase production were tested. Optimum pH value for laccase production in soluble starch yeast extract medium was determined as pH 3.0 with 15425.0 U l–1laccase production at 12th day of cultivation. In addition, effects of eight inducers (veratryl alcohol, ferulic acid, 1‐Hydroxybenzotriazole, syringic acid, 2,2‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonate), 1 mmol l–1 CuSO4, 3% ethanol, guaiacol) were examined. Only cultures with 2,5‐xylidine exhibited 1.9 fold increase in laccase activity reaching to 28890.0 U l–1. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antibiotics production by an actinomycete isolated from the termite gut
Authors: Matsui Toru , Tanaka Junichi , Namihira Tomoyuki , Shinzato Naoya 
Published: February 2012

AbstractAs well as the search for new antibiotics, a new resource or strains for the known antibiotics is also important. Microbial symbionts in the gut of termites could be regarded as one of the feasible resource for such purpose. In this study, antibiotic‐producing actinomycetes were screened from symbionts of the termite gut. 16SrRNA sequence analysis for the 10 isolates revealed that they belong to actinomycetes such as Streptomyces sp., Kitasatospora sp., and Mycobacterium sp. A culture broth from one of the isolate, namely strain CA1, belonging to the genera Streptomyces exhibited antagonistic activity against actinomycetes (Micrococcus spp.), gram‐positive bacteria (Bacillus spp.), and yeast (Candida spp.). The structures of 2 compounds isolated from the culture broth of the strain CA1 were identified as those of actinomycin X2 and its analog, D. This study is the first to report that some symbionts of the termite gut are antibiotic‐producing actinomycetes, and suggest that the termite gut is a feasible resource for bioprospecting. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of the fungal mycotoxin patulin on the chromatin structure of fission yeast Schizosaccharomyces pombe
Authors: Horvath Eszter , Nagy Gabor , Turani Melinda , Balogh Eniko , Papp Gabor , Pollak Edit , Pocsi Istvan , Pesti Miklos , Banfalvi Gaspar 
Published: February 2012

AbstractThe fungal mycotoxin patulin is produced by several molds, especially by Aspergillus and Penicillium. The aim of this study was to clarify whether patulin causes alterations in plasma membrane permeability of Schizosaccharomyces pombe lead to cellular shrinkage charateristic to apoptosis or increases cell size indicating necrosis in cells. Transmission and scanning electronmicroscopy revealed that lower concentrations of patulin induced cellular shrinkage and blebbing, higher concentration caused expansion without cellular disruption. Large‐scale morphological changes of individual cells were followed by time lapse video microscopy. Patulin caused the elongation and stickiness of cells or rounded up their shapes. To visualize chromatin structures of S. pombe nuclei upon patulin treatment, protoplasts were isolated from S. pombe and subjected to fluorescent microscopy. Chromatin changes in the presence of 50 μM patulin concentration were characterized by elongated nuclei containing sticky fibrillary chromatin and enlarged round shaped nuclei trapped at the fibrillary stage of chromatin condensation. Short (60 min) incubation of S. pombe cells in the presence of high (500 μM) patulin concentration generated patches of condensed chromatin bodies inside the nucleus and caused nuclear expansion, with the rest of chromatin remaining in fibrillary form. Longer (90 min, 500 μM) incubation resulted in fewer highly condensed chromatin patches and in nuclear fragmentation. Although, high patulin concentration increased the size of S. pombe size, it did not lead to necrotic explosion of cells, neither did the fragmented nuclei resemble apoptotic bodies that would have indicated programmed cell death. All these morphological changes and the high rate of cell survival point to rapid adaptation and mixed type of fungistatic effects. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photodynamic induced uptake of liposomal doxorubicin to rat lung tumors parallels tumor vascular density
Authors: Wang Yabo , Gonzalez Michel , Cheng Cai , Haouala Amina , Krueger Thorsten , Peters Solange , Decosterd Laurent‐Arthur , van den Bergh Hubert , Perentes Jean Y. , Ris Hans‐Beat , Letovanec Igor , Debefve Elodie 
Published: February 2012

AbstractBackgroundVisudyne®‐mediated photodynamic therapy (PDT) at low drug/light conditions has shown to selectively enhance the uptake of liposomal doxorubicin in subpleural localized sarcoma tumors grown on rodent lungs without causing morphological alterations of the lung. The present experiments explore the impact of low‐dose PDT on liposomal doxorubicin (Liporubicin™) uptake to different tumor types grown on rodent lungs.Material and MethodsThree groups of Fischer rats underwent subpleural generation of sarcoma, mesothelioma, or adenocarcinoma tumors on the left lung. At least five animals of each group (sarcoma, n = 5; mesothelioma, n = 7; adenocarcinoma, n = 5) underwent intraoperative low‐dose (10 J/cm2 at 35 mW/cm2) PDT with 0.0625 mg/kg Visudyne® of the tumor and the lower lobe. This was followed by intravenous (IV) administration of 400 µg Liporubicin™. After a circulation time of 60 min, the tumor‐bearing lung was processed for HPLC analyses. At least five animals per group underwent the same procedure but without PDT (sarcoma, n = 5; mesothelioma, n = 5; adenocarcinoma, n = 6). Five untreated animals per group underwent CD31 immunostaining of their tumors with histomorphometrical assessment of the tumor vascularization.ResultsLow‐dose PDT significantly enhanced Liporubicin™ uptake to all tumor types (sarcoma, P = 0.0007; mesothelioma, P = 0.001; adenocarcinoma, P = 0.02) but not to normal lung tissue compared to IV drug administration alone. PDT led to a significantly increased ratio of tumor to lung tissue drug uptake for all three tumor types (P < 0.05). However, the tumor drug uptake varied between tumor types and paralleled tumor vascular density. The vascular density was significantly higher in sarcoma than in adenocarcinoma (P < 0.001) and mesothelioma (P < 0.001), whereas there was no significant difference between adenocarcinoma and mesothelioma.ConclusionLow‐dose Visudyne®‐mediated PDT selectively enhances the uptake of systemically administered liposomal doxorubicin in tumors without affecting the drug uptake to normal lung. However, drug uptake varied significantly between tumor types and paralleled tumor vascular density. Lasers Surg. Med. 44:318–324, 2012. © 2012 Wiley Periodicals, Inc.