bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrical stimulation modulates osteoblast proliferation and bone protein production through heparin‐bioactivated conductive scaffolds
Authors: Meng Shiyun , Rouabhia Mahmoud , Zhang Ze 
Published: November 2012

AbstractElectrical fields are known to interact with human cells. This principle has been explored to regulate cellular activities for bone tissue regeneration. In this work, Saos‐2 cells were cultured on conductive scaffolds made of biodegradable poly(L‐lactide) and the heparin‐containing, electrically conducting polypyrrole (PPy/HE) to study their reaction to electrical stimulation (ES) mediated through such scaffolds. Both the duration and intensity of ES enhanced cell proliferation, generating a unique electrical intensity and temporal “window” within which osteoblast proliferation was upmodulated in contrast to the downmodulation or ineffectiveness in other ES regions. The favourable ES intensity (200 mV/mm) was further investigated in terms of the gene activation and protein production of two important osteoblast markers characterised by extracellular matrix maturation and mineralisation, that is alkaline phosphatase (ALP) and osteocalcin (OC). Both genes were found activated and the relevant protein production increased significantly following ES. In contrast, ES in the down‐modulation region (400 mV/mm) suppressed the production of both ALP and OC. This work demonstrated that important osteoblast markers can be modulated with specific ES parameters mediated through conductive polymer substrates, providing a unique strategy for bone tissue engineering. Bioelectromagnetics 34:189–199, 2013. © 2012 Wiley Periodicals, Inc.
Microfluidic systems: A new toolbox for pluripotent stem cells
Authors: Lesher‐Perez Sasha Cai , Frampton John P. , Takayama Shuichi 
Published: November 2012

AbstractConventional culture systems are often limited in their ability to regulate the growth and differentiation of pluripotent stem cells. Microfluidic systems can overcome some of these limitations by providing defined growth conditions with user‐controlled spatiotemporal cues. Microfluidic systems allow researchers to modulate pluripotent stem cell renewal and differentiation through biochemical and mechanical stimulation, as well as through microscale patterning and organization of cells and extracellular materials. Essentially, microfluidic tools are reducing the gap between in vitro cell culture environments and the complex and dynamic features of the in vivo stem cell niche. These microfluidic culture systems can also be integrated with microanalytical tools to assess the health and molecular status of pluripotent stem cells. The ability to control biochemical and mechanical input to cells, as well as rapidly and efficiently analyze the biological output from cells, will further our understanding of stem cells and help translate them into clinical use. This review provides a comprehensive insignt into the implications of microfluidics on pluripotent stem cell research.
A simple eccentric stirred tank mini‐bioreactor: Mixing characterization and mammalian cell culture experiments
Authors: Bulnes‐Abundis David , Carrillo‐Cocom Leydi M. , Aráiz‐Hernández Diana , García‐Ulloa Alfonso , Granados‐Pastor Marisa , Sánchez‐Arreola Pamela B. , Murugappan Gayathree , Alvarez Mario M. 
Published: November 2012

AbstractIn industrial practice, stirred tank bioreactors are the most common mammalian cell culture platform. However, research and screening protocols at the laboratory scale (i.e., 5–100 mL) rely primarily on Petri dishes, culture bottles, or Erlenmeyer flasks. There is a clear need for simple—easy to assemble, easy to use, easy to clean—cell culture mini‐bioreactors for lab‐scale and/or screening applications. Here, we study the mixing performance and culture adequacy of a 30 mL eccentric stirred tank mini‐bioreactor. A detailed mixing characterization of the proposed bioreactor is presented. Laser induced fluorescence (LIF) experiments and computational fluid dynamics (CFD) computations are used to identify the operational conditions required for adequate mixing. Mammalian cell culture experiments were conducted with two different cell models. The specific growth rate and the maximum cell density of Chinese hamster ovary (CHO) cell cultures grown in the mini‐bioreactor were comparable to those observed for 6‐well culture plates, Erlenmeyer flasks, and 1 L fully instrumented bioreactors. Human hematopoietic stem cells were successfully expanded tenfold in suspension conditions using the eccentric mini‐bioreactor system. Our results demonstrate good mixing performance and suggest the practicality and adequacy of the proposed mini‐bioreactor. Biotechnol. Bioeng. 2013; 110: 1106–1118. © 2012 Wiley Periodicals, Inc.
Value of laparoscopy before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal carcinomatosis
Authors: Iversen L H , Rasmussen P C , Laurberg S 
Published: November 2012

Abstract

Background
The outcome of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) depends on the extent of peritoneal carcinomatosis. The role of laparoscopy in the preoperative assessment of extent of peritoneal carcinomatosis in potential candidates for cytoreductive surgery and HIPEC was evaluated in a consecutive series.

Methods
Patients with peritoneal carcinomatosis from colorectal cancer or appendiceal cancer, pseudomyxoma peritonei or peritoneal mesothelioma referred to a single, national HIPEC centre were included prospectively between June 2006 and January 2012. From September 2010, preoperative evaluation also included a laparoscopy in patients deemed amenable to cytoreductive surgery and HIPEC after radiological evaluation, apart from those with pseudomyxoma peritonei with massive amounts of mucin.

Results
In the period before laparoscopic evaluation, 70 patients underwent laparotomy of whom 39 (56 per cent) completed cytoreductive surgery and HIPEC. After the introduction of laparoscopic assessment, diagnostic laparoscopy was planned in 45 patients and successful in 43. The laparoscopic evaluation excluded 18 patients from surgery because of extensive disease, among other reasons. Laparoscopy was uneventful and associated with no deaths. Twenty-seven patients were considered amenable to cytoreductive surgery and HIPEC based on laparoscopic findings, of whom 17 completed this treatment; the disease was unresectable in the remaining ten patients. Of 13 patients who were not eligible for laparoscopic evaluation and were subjected to cytoreductive surgery plus HIPEC, 11 completed the procedure. The overall completion rate of cytoreductive surgery and HIPEC increased to 70 per cent (28 of 40) after the introduction of laparoscopic evaluation.

Conclusion
Diagnostic laparoscopy was valuable in preoperative evaluation of the extent of peritoneal carcinomatosis, and improved patient selection for cytoreductive surgery and HIPEC.
Affinity chromatographic purification of human immunoglobulin a from chinese hamster ovary cell culture supernatant
Authors: Liu Zhuo , Gurgel Patrick V. , Carbonell Ruben G. 
Published: November 2012

AbstractHexamer peptide ligand HWRGWV, initially screened from a solid phase combinatorial peptide library for immunoglobulins G (IgG) purification, is shown to also have potential for immunoglobulin A (IgA) purification. The determined dissociation constants for hIgA on HWRGWV resins at three different peptide densities from 0.11 to 0.55 meq/g fall in the range of 10−6–10−7 M, which are somewhat lower than those for hIgG. Although relatively low dynamic binding capacity (DBC) in the range of 9.2–16.8 mg IgA/mL resin at linear flow rates from 173 to 35 cm/h were obtained for IgA compared to IgG, the DBC value of HWRGWV for IgA is much greater than current commercially available affinity ligands. Although relatively lower binding affinity to secretory IgA compared to monomeric IgA was observed, the peptide ligand resins exhibit great potential for large‐scale purification of both human IgA and secretory IgA. Recoveries of 96.0% and 94.3%, and purities of 90.3% and 91.7% were achieved for human IgA and secretory IgA purification, respectively, from spiked Chinese hamster ovary cell culture supernatants without an extra afterwash step. Over 95% in purities were achieved for IgA and secretory IgA with an extra afterwash step; however, the recoveries would decrease at least 15% and 40% for IgA and secretory IgA, respectively. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Downstream processing, characterization, and structure–function relationship of solvent‐, detergent‐, psychro‐, thermo‐, alkalistable metalloprotease from metal‐, solvent‐tolerant psychrotrophic Pseudomonas putida SKG‐1 isolate
Authors: Singh Santosh Kumar , Singh Sanjay Kumar , Tripathi Vinayak Ram , Garg Satyendra Kumar , Khare Sunil Kumar 
Published: November 2012

AbstractThe purification and characterization of psychro‐thermoalkalistable protease from psychrotrophic Pseudomonas putida isolate is being reported for the first time. A ∼53 kDa protease was purified 21.4‐folds with 57.2% recovery by ultrafiltration and hydrophobic interaction chromatography. Kinetic analyses revealed the Km and Vmax to be 1.169 mg mL−1 and 0.833 mg mL−1 min−1, respectively. The kcat value of 3.05 × 102 s−1 indicated high affinity and catalytic efficiency toward casein. The protease was most active at pH 9.5 and 40°C, with 100% stability in pH and temperature range of 6.0–11.0 and 10–40°C, respectively. Presence of Zn2+ increased the thermostability of protease (at 70°C) by 433%. Ethylene diamine tetra acetic acid (EDTA) and 1,10‐phenanthroline were inhibitory, whereas phenyl methyl sulfonyl fluoride (PMSF), p‐chloro mercuric benzoate (PCMB), and β‐mercaptoethanol were ineffective, revealing the enzyme to be a metalloprotease. Zinc, calcium, iron, nickel, and copper at 1 mM increased the enzyme activity (102–134%). Complete reversion of enzyme inhibition (caused by Ethylene diamine tetra acetic acid [EDTA]) by Zn2+ affirmed this enzyme as zinc‐dependent metalloprotease. At 0.1% concentration, Triton X‐100 and Tween 80 slightly increased, while SDS and H2O2 reduced the protease activity. In the presence of 0.1% commercial detergents, the enzyme was fairly stable (54–81%). In the presence of organic solvent, the protease was remarkably stable exhibiting 72–191% activities. In contrast, savinase exhibited good stability in the presence of hydrophilic solvents, while chymotrypsin showed elevated activities with benzene, toluene, and xylene only. Circular dichroism analysis revealed the protease as a β‐rich protein, having large fraction (∼40%) of β‐sheets. Presence of different environmental conditions altered the β‐content, which accordingly affected the protease activity. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Direct and indirect use of GFP whole cell biosensors for the assessment of bioprocess performances: Design of milliliter scale‐down bioreactors
Authors: Brognaux Alison , Thonart Philippe , Delvigne Frank , Neubauer Peter , Twizere Jean‐Claude , Francis Frédéric , Gorret Nathalie 
Published: November 2012

AbstractSubstrate limitation responsive biosensors have been used for the development of a mini‐bioreactor platform that can be used as a scale‐down tool. Three green fluorescent protein (GFP) transcriptional reporters have been chosen in Escherichia coli, i.e., uspA::gfp, csiE::gfp, and yciG::gfp. Our previous studies have shown that these kinds of promoters are induced in response to substrate limitation and are significantly repressed when cultures are carried out in heterogeneous bioreactors. This sensitivity to substrate limitation has been confirmed in the case of the csiE and yciG biosensors. A mini‐scale‐down platform is proposed as a high throughput tool to rapidly investigate the usefulness of a given microbial biosensor. This platform is composed of shake flasks able to operate in fed‐batch mode either using the slow release or the intermittent feeding principle. Local heterogeneities were reproduced at the level of these mini‐bioreactors (operating under the intermittent feeding principle) and caused a decrease in GFP expression as in conventional scale‐down reactors. The presence of GFP in supernatants was also noted and seems to be correlated with the substrate limitation signal for the three cultivation systems considered in this work (i.e., chemostat, conventional and mini‐bioreactors) and with membrane permeability. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
A novel counter‐selection method for markerless genetic modification in Synechocystis sp. PCC 6803
Authors: Cheah Yi Ern , Albers Stevan C. , Peebles Christie A. M. 
Published: November 2012

AbstractThe cyanobacterium Synechocystis sp. PCC 6803 is a photosynthetic organism capable of efficient harnessing of solar energy while capturing CO2 from the environment. Methods to genetically alter its genomic DNA are essential for elucidating gene functions and are useful tools for metabolic engineering. In this study, a novel counter‐selection method for the genetic alteration of Synechocystis was developed. This method utilizes the nickel inducible expression of mazF, a general protein synthesis inhibitor, as a counter‐selection marker. Counter‐selection is particularly useful because the engineered strain is free of any markers which make further genetic modification independent of available antibiotic resistance genes. The usability of this method was further demonstrated by altering genes at several loci in two variants of Synechocystis. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Bioremediation of Phenanthrene by Mycoplana sp. MVMB2 Isolated from Contaminated Soil
Authors: Brinda Lakshmi Mahalingam , Anandaraj Venkataramagounder Perumal , Velan Manickam 
Published: November 2012

AbstractThe effect of nutrient and surfactant addition on the biodegradation of phenanthrene was studied in a batch scale soil–slurry system using isolated Mycoplana sp. MVMB2strain. The study was conducted using an artificially phenanthrene spiked and as well as contaminated soil from petrochemical industrial site. Maximum phenanthrene degradation and subsequent high microbial growth were observed at optimum pH (pH 6) and C/N/P ratio (100:20:3). To investigate maximum substrate degradation potential of Mycoplana sp. MVMB2, very high concentrations of phenanthrene (50–200 mg/kg soil) were used. The organism was capable of degrading >60% for a concentration below 20 mg/kg soil and >40% for concentrations up to 200 mg/kg within 8 days. Further the influence of five different surfactants namely Span 80, Tween 20, Triton X‐100, cetyl trimethyl ammonium bromide, and sodium dodecyl sulfate were tested at their critical micelle concentration (CMC) levels for phenanthrene degradation in the soil. The addition of surfactant enhanced the biodegradation and a maximum of 84.49% was obtained for Triton X‐100. Complete phenanthrene degradation by Mycoplana sp. MVMB2 was observed at 3 CMC concentration of Triton X‐100. The optimized parameters obtained were used for the degradation of phenanthrene present in the contaminated soil and 98.6% biodegradation was obtained. Thus, the results obtained in the study suggested that biodegradation of phenanthrene by Mycoplana sp. MVMB2 appeared to be feasible to remediate phenanthrene rich contaminated sites.
Identification of small molecule inhibitors of cytokinesis and single cell wound repair
Authors: Clark Andrew G. , Sider Jenny R. , Verbrugghe Koen , Fenteany Gabriel , von Dassow George , Bement William M. 
Published: November 2012

AbstractScreening of small molecule libraries offers the potential to identify compounds that inhibit specific biological processes and, ultimately, to identify macromolecules that are important players in such processes. To date, however, most screens of small molecule libraries have focused on identification of compounds that inhibit known proteins or particular steps in a given process, and have emphasized automated primary screens. Here we have used “low tech” in vivo primary screens to identify small molecules that inhibit both cytokinesis and single cell wound repair, two complex cellular processes that possess many common features. The “diversity set”, an ordered array of 1990 compounds available from the National Cancer Institute, was screened in parallel to identify compounds that inhibit cytokinesis in Dendraster excentricus (sand dollar) embryos and single cell wound repair in Xenopus laevis (frog) oocytes. Two small molecules were thus identified: Sph1 and Sph2. Sph1 reduces Rho activation in wound repair and suppresses formation of the spindle midzone during cytokinesis. Sph2 also reduces Rho activation in wound repair and may inhibit cytokinesis by blocking membrane fusion. The results identify two small molecules of interest for analysis of wound repair and cytokinesis, reveal that these processes are more similar than often realized and reveal the potential power of low tech screens of small molecule libraries for analysis of complex cellular processe. © 2012 Wiley Periodicals, Inc.
Functional, anatomical, and neurochemical differentiation of medial preoptic area subregions in relation to maternal behavior in the mouse
Authors: Tsuneoka Yousuke , Maruyama Teppo , Yoshida Sachine , Nishimori Katsuhiko , Kato Tadafumi , Numan Michael , Kuroda Kumi O. 
Published: November 2012

AbstractIn rodents, previous findings indicate critical involvement of the medial preoptic area (MPOA) in the neural control of maternal behavior. However, the specification of the particular MPOA subregions involved in maternal behavior and the identification of the neurochemical phenotype(s) of the essential neurons demands additional study. Therefore, we investigated the chemical neuroanatomy of the essential MPOA subregion for maternal behavior in C57BL/6J female mice. Using the oxytocinergic neurons in the dorsal MPOA as a primary regional marker, we first assessed the distribution of c‐Fos‐expressing neurons in the MPOA during maternal behavior using immunohistochemistry. Results showed that non‐oxytocinergic neurons in the dorsal and ventral MPOA prominently expressed c‐Fos during maternal behavior. Then using excitotoxic lesion studies, we determined the specific MPOA area that is necessary for maternal behavior. Bilateral lesions of the central MPOA, where c‐Fos was expressed only moderately, effectively disrupted maternal behavior, although lesions to the dorsal and ventral MPOA regions were ineffective. These centrally lesioned females were highly infanticidal irrespective of their previous maternal experience. Neurochemical investigations showed that more than 75% of the c‐Fos‐expressing neurons in central MPOA were GABAergic. Many of them also expressed galanin, neurotensin, and/or tachykinin2 mRNAs. Finally, the central MPOA was populated by numerous glutamatergic neurons, although only a small percentage of these neurons colocalized with c‐Fos. To conclude, the central MPOA is the indispensable subregion for mouse maternal behavior, and GABAergic and/or peptidergic neurons in this area were transcriptionally activated during maternal behavior. J. Comp. Neurol. 521:1633–1663, 2013. © 2012 Wiley Periodicals, Inc.
Transgenic labeling of higher order neuronal circuits linked to phospholipase C‐β2–expressing taste bud cells in medaka fish
Authors: Ieki Takashi , Okada Shinji , Aihara Yoshiko , Ohmoto Makoto , Abe Keiko , Yasuoka Akihito , Misaka Takumi 
Published: November 2012

AbstractThe sense of taste plays a pivotal role in the food‐selecting behaviors of vertebrates. We have shown that the fish ortholog of the phospholipase C gene (plc‐β2) is expressed in a subpopulation of taste bud cells that transmit taste stimuli to the central nervous system to evoke favorable and aversive behaviors. We generated transgenic medaka expressing wheat germ agglutinin (WGA) under the control of a regulatory region of the medaka plc‐β2 gene to analyze the neuronal circuit connected to these sensory cells. Immunohistochemical analysis of the transgenic fish 12 days post fertilization revealed that the WGA protein was transferred to cranial sensory ganglia and several nuclei in the hindbrain. WGA signals were also detected in the secondary gustatory nucleus in the hindbrain of 3‐month‐old transgenic fish. WGA signals were observed in several diencephalic and telencephalic regions in 9‐month‐old transgenic fish. The age‐dependent increase in the labeled brain regions strongly suggests that labeling occurred at taste bud cells and progressively extended to cranial nerves and neurons in the central nervous system. These data are the first to demonstrate the tracing of higher order gustatory neuronal circuitry that is associated with a specific subpopulation of taste bud cells. These results provide insight into the basic neuronal architecture of gustatory information processing that is common among vertebrates. J. Comp. Neurol. 521:1781–1802, 2013. © 2012 Wiley Periodicals, Inc.
Pancreatic lipase activity in emulsions containing seed meals: Effect of extrusion
Authors: Shene Carolina , Spuler María José , Leyton Allison , Duarte Carla , Acevedo Francisca , Rubilar Mónica 
Published: November 2012

AbstractThe effect of extrusion of soybean (Glycine max), yellow lupin (Lupinus luteus), and linseed (Linum usitatissimum) on the activity of porcine pancreatic lipase (PPL) was evaluated through pH‐Stat methodology with tributyrin emulsions in which the seed meals [extruded (E) and non‐extruded (NE)] were dispersed. The seed meals affected PPL activity in a concentration‐dependent fashion; at 2.3 mg/mL the meals reduced PPL activity (11.7–45.0% reduction) while the opposite was true (3.1–28.0% increase) at 6.8 mg/mL. PPL activity in the assays containing E‐lupin, E‐soybean and E‐linseed meals at 2.3 mg/mL was 109.7 and 11.3% higher and 25.5% lower than the activity in the emulsions containing the NE‐meals, respectively. The differences between the PPL activity in emulsions containing the extruded and NE‐meals could be due to changes in the emulsifying properties of the meals after extrusion; extrusion increased (10.2%) the emulsification capacity of lupin meal and for linseed meal this property was reduced (9.2%). In spite of the low PPL activity at low meal concentrations, the percentage of free fatty acids released after 30 min was similar to the theoretical maximum (66.6%) with two exceptions – NE‐soybean meal (59.5 ± 2.7%) and E‐linseed meal (57.9 ± 1.2%).Practical applications: Feed and food industries use plant protein sources that contain inhibitors of digestive enzymes. Various proteases inhibitors are inactivated during extrusion being less known the effect of extrusion on lipase inhibitors. Reduction of lypolysis rate, carried out mainly by pancreatic lipase in human and other animals, could influence feed and food consumption because satiety is controlled – at least in part – by undigested lipids. Our results show that extrusion can be used to reduce the inhibitory activity of lupin and soybean on PPL. On the other hand, extrusion of linseed increased the negative effect of this meal on PPL activity effect that could have applications in the development of food and ingredients for weight control.