bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metabolic precursors enhance the production of poly‐ε‐lysine by Streptomyces noursei NRRL 5126
Authors: Bankar Sandip B. , Singhal Rekha S. 
Published: February 2011

AbstractPoly‐ε‐lysine produced by streptomyces species is a promising biopolymer owing to its antimicrobial activity and safety for humans. A number of nutritional factors influencing poly‐ε‐lysine production by Streptomyces noursei NRRL 5126 were studied. Various metabolic precursors such as amino acids, tricarboxylic acid cycle intermediates and cofactors were investigated for improved production of poly‐ε‐lysine. Results indicated L‐aspartate (2 mM) and citric acid (5 mM) to substantially increase the poly‐ε‐lysine production from 97.08 to 409.94 mg/L. Addition of citric acid after 24 h and L‐aspartate after 36 h of fermentation medium further enhanced poly‐ε‐lysine production to 497.67 mg/L after a total fermentation time of 108 h. However, the use of cofactors of enzymes involved in the biosynthesis of poly‐ε‐lysine inhibited its production which is believed to be due to diversion of the flux to other metabolites.
Hyaluronic acid nanofiber wound dressing—production, characterization, and in vivo behavior
Authors: Uppal Rohit , Ramaswamy Gita N. , Arnold C. , Goodband Robert , Wang Y. 
Published: February 2011

AbstractHyaluronic acid (HA) was electrospun. The effects of flow rate, spin length, and the applied voltage on the diameter of the HA nanofibers were analyzed. The average thickness of the webs was 0.041 cm. The air permeability of sterilized HA nanofiber wound dressing was much higher than that of gauze with Vaseline. The degree of crystallinity of HA nanofibers was characterized using powder X‐ray technique and was found to be 20.6%. A preclinical study was conducted to compare healing of wounds covered by an adhesive bandage, a sterilized solid HA, gauze with Vaseline, an antibiotic dressing, and a sterilized HA nanofiber wound dressing. Results of the two methods of appraisal showed that the sterilized HA nanofiber wound dressing was the best type of dressing out of the five types of dressings compared. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Silver/hydroxyapatite composite coatings on porous titanium surfaces by sol‐gel method
Authors: Qu Jie , Lu Xiong , Li Dan , Ding Yonghui , Leng Yang , Weng Jie , Qu Shuxin , Feng Bo , Watari Fumio 
Published: February 2011

AbstractHydroxyapatite (HA) coatings loaded with nanosilver particles is an attractive method to impart the HA coating with antibacterial properties. Producing Ag/HA coatings on porous Ti substrates have been an arduous job since commonly used line‐of‐sight techniques are not able to deposit uniform coatings on the inner pore surfaces of the porous Ti. In this study, porous Ti scaffolds with high porosity and interconnected structures were prepared by polymer impregnating method. A sol‐gel process was used to produce uniform Ag/HA composite coatings on the surfaces of porous Ti substrates. Ca(NO3)2·4H2O and P2O5in an ethyl alcohol based system was selected to prepare the sol, which ensured the homogeneous distribution of Ag in the sol. The characterization revealed that silver particles uniformly distributed in the coatings without agglomeration. High antibacterial ratio (>95%), againstE. coliandS. albuswas expressed by the silver‐containing coatings (Ag/HA 0.8 and 1.6 wt %). The biocompatibility of the Ag/HA 0.8 surfaces was as good as that of pure HA surface, as revealed by culturing osteoblasts on them. The results indicated that Ag/HA 0.8 had the good balance between the biocompatibility and antibacterial properties of the coatings. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Development of a biodegradable tissue adhesive based on functionalized 1,2‐ethylene glycol bis(dilactic acid). II.
Authors: Rohm Henning W. , Lurtz Claudia , Wegmann Juergen , Odermatt Erich K. , Behrend Detlef , Schmitz Klaus‐Peter , Sternberg Katrin 
Published: February 2011

AbstractIn body regions where damage and bleeding must be avoided, a substitute for mechanical tissue fixation by sutures or staplers is needed. Since tissue adhesives provide easy and fast handling they are a promising alternative. The present study reports the development and analysis of a tissue adhesive that consists of two adhesive components: hexamethylene diisocyanate (HDI) functionalized 1,2‐ethylene glycol bis(dilactic acid) (ELA‐NCO) and chitosan chloride. This composition was chosen based on preliminary studies on several chain elongation agents. The present study evaluates this adhesive system by IR‐spectroscopy, tensile tests, and gel point measurements in comparison to fibrin glue. The system's in vitro biocompatibility was tested with mouse fibroblasts (L929) according to ISO 10993‐5. Furthermore, an implantation study was performed in SPF‐Wistar rats. The adhesive strength of manually applied mixtures or mixtures applied by double chamber syringes with a mixing extruder was determined to be significantly higher than that of fibrin glue on bovine muscle tissue at 37°C. Tensile strength increased further when exposure time of the adhesive was increased from 10 min to 48 h. The rheological gel point determination showed that the mixture of ELA‐NCO/DMSO and chitosan chloride offers a time window large enough to readjust the fused joint during surgery, as opposed to fibrin glue. Additionally, the in vitro and in vivo biocompatibility studies of the adhesive system revealed no toxic effects on the surrounding tissue. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Telomerase-deficient mice exhibit bone loss owing to defects in osteoblasts and increased osteoclastogenesis by inflammatory microenvironment
Authors: Saeed Hamid , Abdallah Basem M , Ditzel Nicholas , Catala-Lehnen Philip , Qiu Weimin , Amling Michael , Kassem Moustapha 
Published: February 2011

Abstract
Telomere shortening owing to telomerase deficiency leads to accelerated senescence of human skeletal (mesenchymal) stem cells (MSCs) in vitro, whereas overexpression leads to telomere elongation, extended life span, and enhanced bone formation. To study the role of telomere shortening in vivo, we studied the phenotype of telomerase-deficient mice (Terc−/−). Terc−/− mice exhibited accelerated age-related bone loss starting at 3 months of age and during 12 months of follow-up revealed by dual-energy X-ray absorptiometric (DXA) scanning and by micro–computed tomography (µCT). Bone histomorphometry revealed decreased mineralized surface and bone-formation rate as well as increased osteoclast number and size in Terc−/− mice. Also, serum total deoxypyridinoline (tDPD) was increased in Terc−/− mice. MSCs and osteoprogenitors isolated from Terc−/− mice exhibited intrinsic defects with reduced proliferating cell number and impaired osteogenic differentiation capacity. In addition, the Terc−/−-MSC cultures accumulated a larger proportion of senescent β-galactosidase+ cells and cells exhibiting DNA damage. Microarray analysis of Terc−/− bone revealed significant overexpression of a large number of proinflammatory genes involved in osteoclast (OC) differentiation. Consistently, serum obtained from Terc−/− mice enhanced OC formation of wild-type bone marrow cultures. Our data demonstrate two mechanisms for age-related bone loss caused by telomerase deficiency: intrinsic osteoblastic defects and creation of a proinflammatory osteoclast-activating microenvironment. Thus telomerization of MSCs may provide a novel approach for abolishing age-related bone loss. © 2011 American Society for Bone and Mineral Research.
Exposure to community violence among Arab youth in Israel: rates and characteristics
Authors: Haj‐Yahia Muhammad M. , Leshem Becky , Guterman Neil 
Published: February 2011

AbstractThe research explored the rates and characteristics of exposure to community violence (CV) and its relevance to several sociodemographic factors among a sample of 833 Arab youth aged 14–18 years residing in diverse residential areas in Israel. Data were collected using a self‐report questionnaire. The frequency of exposure to CV during the past 12 months correlated significantly with the children's gender. The frequency of witnessing CV during that period was higher than the frequency of personally experiencing CV, and exposure to mild CV incidents during that period was higher than the frequency of exposure to severe CV incidents during the same period, with no significant relationship to sociodemographic factors. Participants reported higher rates of exposure to most CV incidents outside of the neighborhood; however, exposure to beating was higher inside the participants' neighborhood. Moreover, the highest overall rate of exposure to CV was at school. © 2011 Wiley Periodicals, Inc.
Social class as moderator of the relationship between (dis)empowering processes and psychological empowerment
Authors: Christens Brian D. , Speer Paul W. , Peterson N. Andrew 
Published: February 2011

AbstractThis study examined whether social class moderated the relationship between empowering and disempowering processes and psychological empowerment (PE) in a sample of individuals from five community organizing initiatives (N=490). Hierarchical regression analyses were used to test the relationship between community participation (CP) and alienation on the intrapersonal and interactional components of PE. For the intrapersonal component of PE, CP and alienation were, respectively, positive and negatively predictive. Social class was positively related to the intrapersonal component of PE, and no interaction effects were detected. For the interactional component of PE, CP was not a significant predictor, and alienation was a significant positive predictor. Social class was a negative predictor, and interaction effects between independent variables were detected. These paradoxical relationships between social class and the components of PE are pertinent to empowerment theory and measurement. Implications for social policy, community interventions, and evaluation are explored. © 2011 Wiley Periodicals, Inc.
Human salivary gland acinar cells spontaneously form three‐dimensional structures and change the protein expression patterns
Authors: Chan Yen‐Hui , Huang Tsung‐Wei , Young Tai‐Horng , Lou Pei‐Jen 
Published: February 2011

AbstractApplying tissue engineering principles to design an auto‐secretory device is a potential solution for patients suffering loss of salivary gland function. However, the largest challenge in implementing this solution is the primary culture of human salivary gland cells, because the cells are highly differentiated and difficult to expand in vitro. This situation leads to the lack of reports on the in vitro cell biology and physiology of human salivary gland cells. This study used a low‐calcium culture system to selectively cultivate human parotid gland acinar (PGAC) cells from tissues with high purity in cell composition. This condition enables PGAC cells to continuously proliferate and retain the phenotypes of epithelial acinar cells to express secreting products (α‐amylase) and function‐related proteins (aquaporin‐3, aquaporin‐5, and ZO‐1). Notably, when the cells reached confluence, three‐dimensional (3D) cell aggregates were observed in crowded regions. These self‐formed cell spheres were termed post‐confluence structures (PCSs). Unexpectedly, despite being cultured in the same media, cells in PCSs exhibited higher expression levels and different expression patterns of function‐related proteins compared to the two‐dimensional (2D) cells. Translocation of aquoporin‐3 from cytosolic to alongside the cell boundaries, and of ZO‐1 molecules to the boundary of the PCSs were also observed. These observations suggest that when PGAC cells cultured on the 2D substrate would form PCSs without the help of 3D scaffolds and retain certain differentiation and polarity. This phenomenon implies that it is possible to introduce 2D substrates instead of 3D scaffolds into artificial salivary gland tissue engineering. J. Cell. Physiol. 226: 3076–3085, 2011. © 2011 Wiley‐Liss, Inc.
Chondrogenesis of the limbs and mesopodial ossification of Podocnemis expansa Schweigger, 1812 (Testudines: Podocnemidae)
Authors: Vieira Lucélia Gonçalves , Santos André L.Q. , Lima Fabiano Campos , Moura Lea Resende 
Published: February 2011

AbstractWe address the chondrogenic formation of the limbs and the mesopodial ossification pattern of the Pleurodira Podocnemis expansa, to resolve the homology of these elements as well as the pattern of connection of the autopodial elements and the origin of the digital arch. Embryos and juveniles of P. expansa were cleared and stained for cartilage and bone. The fore‐ and hind‐limbs were also studied histologically. We describe the development of the stylopodium and zeugopodium originating from a Y‐shaped cartilaginous condensation, and the differentiation of the primary axis and the digital arch in the initial stages of limb development. The most pronounced changes were observed in the chondrogenic pattern and ossification of the mesopodium, although development of the digits is similar and we found no ontogenetic reduction such as that described for other Testudines. In this study, as in previous research involving several groups of reptilian sauropsids, we found an inconsistent pattern between the chondrogenic formation and mesopodial ossification of the limbs, indicating that these developmental events are dissociated. In summary, the chondrogenic and ossification sequences of these elements do not follow the same pattern. In addition, the differences found between P. expansa and other species to which it was compared clearly indicate that these events follow more than one pattern in Testudines. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Angioarchitecture of the bovine spermatic cord
Authors: Polguj Michał , Jȩdrzejewski Kazimierz S. , Topol Mirosław 
Published: February 2011

AbstractWe described the topography and morphometry of the testicular artery, pampiniform plexus veins, and indirect connections between them in the spermatic cord of the bull. Sixty microcorrosive casts of bovine spermatic cords were analyzed macroscopically, by stereomicroscopy, and by scanning electron microscopy. The average size of the testicles was 94.6 × 49.7 × 54.7 mm. The testicular artery formed a superiorly pointed cone‐like structure with its base fixed to the proximal part of the gonad. The artery gave off one or two branches to the head of epididymis and to the deferens duct. The pampiniform plexus originated from intra‐tunical veins. Veins of the pampiniform plexus were of smaller diameter but larger number than intra‐tunical ones. The density of the veins of the pampiniform plexus was 9.37 ± 1.07 mm−2. The testicular vein began 90–121 mm above the superior pole of the testis. In 2.9% of specimens, the testicular vein was doubled. Numerous anastomoses among veins of pampiniform plexus were observed. Additionally, indirect anastomoses between the testicular artery and pampiniform plexus veins formed by the capillary network of the vasa vasorum of the testicular artery were visualized by scanning electron microscopy. In all cases, narrowings in the casts of the precapillary vessel were observed. We also documented the vasa vasorum of the testicular artery in bulls. The density of these vessels was 22.87 ± 11.48 mm−2. The indirect arteriovenous connections together with the presence of circular constrictions of the lumen in precapillary vessels may play a role in testicular blood flow regulation. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Neurotoxic properties of the anabolic androgenic steroids nandrolone and methandrostenolone in primary neuronal cultures
Authors: Caraci Filippo , Pistarà V. , Corsaro A. , Tomasello Flora , Giuffrida Maria Laura , Sortino Maria Angela , Nicoletti Ferdinando , Copani Agata 
Published: February 2011

AbstractAnabolic‐androgenic steroid (AAS) abuse is associated with multiple neurobehavioral disturbances. The sites of action and the neurobiological sequels of AAS abuse are unclear at present. We investigated whether two different AASs, nandrolone and methandrostenolone, could affect neuronal survival in culture. The endogenous androgenic steroid testosterone was used for comparison. Both testosterone and nandrolone were neurotoxic at micromolar concentrations, and their effects were prevented by blockade of androgen receptors (ARs) with flutamide. Neuronal toxicity developed only over a 48‐hr exposure to the steroids. The cell‐impermeable analogues testosterone‐BSA and nandrolone‐BSA, which preferentially target membrane‐associated ARs, were also neurotoxic in a time‐dependent and flutamide‐sensitive manner. Testosterone‐BSA and nandrolone‐BSA were more potent than their parent compounds, suggesting that membrane‐associated ARs were the relevant sites for the neurotoxic actions of the steroids. Unlike testosterone and nandrolone, toxicity by methandrostenolone and methandrostenolone‐BSA was insensitive to flutamide, but it was prevented by the glucocorticoid receptor (GR) antagonist RU‐486. Methandrostenolone‐BSA was more potent than the parent compound, suggesting that its toxicity relied on the preferential activation of putative membrane‐associated GRs. Consistently with the evidence that membrane‐associated GRs can mediate rapid effects, a brief challenge with methandrostenolone‐BSA was able to promote neuronal toxicity. Activation of putative membrane steroid receptors by nontoxic (nanomolar) concentrations of either nandrolone‐BSA or methandrostenolone‐BSA became sufficient to increase neuronal susceptibility to the apoptotic stimulus provided by β‐amyloid (the main culprit of AD). We speculate that AAS abuse might facilitate the onset or progression of neurodegenerative diseases not usually linked to drug abuse. © 2011 Wiley‐Liss, Inc.
Involvement of interleukin‐1 in lipopolysaccaride‐induced microglial activation and learning and memory deficits
Authors: Tanaka S. , Kondo H. , Kanda K. , Ashino T. , Nakamachi T. , Sekikawa K. , Iwakura Y. , Shioda S. , Numazawa S. , Yoshida T. 
Published: February 2011

AbstractWe have developed an animal model of learning and memory impairment associated with activation of microglia in the mouse brain. Injection of lipopolysaccharide into the CA1 region of the mouse hippocampus resulted in an increased production of inflammatory cytokines, such as interleukin‐1β. Immunostaining for interleukin‐1β revealed an increase in the signal at 6 hr after lipopolysaccharide injection. Immunopositive cells for interleukin‐1β were colocalized with those immunopositive for CD11b. When subacute lipopolysaccharide treatment (20 μg/2 μl/injection, bilaterally for 5 consecutive days) was performed, long‐term activation of microglia and learning and memory deficits as evaluated using a step‐through passive avoidance test were observed in the wild‐type mice. Gene expression of the N‐methyl‐D‐aspartate receptor NR1 and NR2A subunits was also decreased by the lipopolysaccharide treatment. In contrast, activation of microglia and the associated behavioral deficits were not observed in mice lacking interleukin‐1α and ‐1β following the subacute lipopolysaccharide treatment, together with little change in the gene expression of NR1 and NR2A subunits. However, the subacute lipopolysaccharide treatment produced almost similar changes in those parameters in the tumor necrosis factor‐α knockout mice as in the wild‐type animals. The injection of interleukin‐1β neutralizing antibody with lipopolysaccharide for 5 consecutive days resulted in the improvement of lipopolysaccharide‐induced learning and memory deficits. These findings suggest that the expression of interleukin‐1 plays an important role in lipopolysaccharide‐induced activation of microglia and the associated functional deficits in learning and memory. © 2011 Wiley‐Liss, Inc.
Differential effects of the HESR/HEY transcription factor family on dopamine transporter reporter gene expression via variable number of tandem repeats
Authors: Kanno Kouta , Ishiura Shoichi 
Published: February 2011

AbstractThe 3′‐untranslated region (UTR) of the human dopamine transporter (DAT1) gene contains a variable number of tandem repeats (VNTR) domain, which is thought to be associated with dopamine‐related psychiatric disorders, personality, and behavior. However, the molecular and neuronal functions of polymorphisms within the VNTR domain are unknown. We previously identified the transcription factor HESR1 (HEY1) as a VNTR‐binding protein. Hesr1 knockout mice exhibit DAT up‐regulation in the brain and low levels of spontaneous activity. Other members of the HESR (HEY) family, including HESR2 (HEY2) and 3 (HEYL), have similar DNA‐binding domains. In this study, we analyzed the effects of HESR1, ‐2, and ‐3 on DAT1 expression in human neuroblastoma SH‐SY5Y cells using luciferase reporter assays. We found that the VNTR domain played an inhibitory role in DAT1 reporter gene expression and that HESR1 and ‐2 inhibited expression via both the core promoter and the VNTR. The inhibitory effects of HESR family members on DAT reporter gene expression differed depending on the number of repeats in the VNTR domain. We also found that each Hesr was expressed in the dopaminergic neurons in the mouse midbrain. These results suggest that the HESR family is involved in DAT expression via the VNTR domain. © 2011 Wiley‐Liss, Inc.
Global network initiative: An ethical compass for information and communications firms in the internet age
Authors: Hope Dunstan 
Published: February 2011

AbstractWith the explosive growth of communications technologies, organizations are facing new ethical challenges in using, gathering, storing, and sharing information that can cast them in a negative light and lead to restrictions on how they conduct business. As Yahoo!, Microsoft, and Google discovered, developing agreed‐upon principles and guidelines to direct behavior, co‐drafted by a range of stakeholders, is a practical step toward maintaining the public's trust while preserving organizational business models and protecting human rights. Moreover, their experience with the Global Network Initiative offers practical lessons on how to effectively forge multistakeholder collaboration to address complex policy. © 2011 Wiley Periodicals, Inc.
Taking a fast‐cycle approach to align organizational culture with business plans
Authors: Recardo Ronald J. 
Published: February 2011

AbstractStudies show that organizations that closely align their culture in support of their business strategy outperform their competitors in both the short and long term. As this organization's experience illustrates, companies of all sizes can tap into their existing technology, organization, and process architecture to effect long‐lasting change in less than 50 percent of the time of other programs. To do so, they need to analyze their strategic direction and identify the gaps between their actual and desired cultural characteristics, values, and behaviors. © 2011 Wiley Periodicals, Inc.
Comprehensive two‐dimensional liquid chromatography with evaporative light‐scattering detection for the analysis of triacylglycerols in Borago officinalis
Authors: Mondello Luigi , Beccaria Marco , Donato Paola , Cacciola Francesco , Dugo Giovanni , Dugo Paola 
Published: February 2011

AbstractAn optimized 2‐D liquid chromatography (LC×LC) set‐up, based on the different selectivities of a silver ion (Ag) and a non‐aqueous reversed phase (NARP), employed in the first (D1) and the second dimension (D2), respectively, in combination with evaporative light‐scattering detection (ELSD), has been developed for the analysis of the triacylglycerol (TAG) fraction in a Borago officinalis oil. The 2‐D set‐up, thanks to the complementary separation selectivity provided by the two columns, allowed to distribute 78 TAGs throughout the 2‐D LC retention plane otherwise unachievable by 1‐D LC.