bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of flow conditions in 2 L and 20 L wave bioreactors® using computational fluid dynamics
Authors: Öncül Alper A. , Kalmbach Andreas , Genzel Yvonne , Reichl Udo , Thévenin Dominique 
Published: November 2009

AbstractCharacterization of flow conditions is of great importance to control cell growth and cell damage in animal cell culture because cell viability is influenced by the flow properties in bioreactors. Alternative reactor types like Wave Bioreactors® have been proposed in recent years, leading to markedly different results in cell growth and product formation. An advantage of Wave Bioreactors® is the disposability of the Polyethylenterephthalet‐bags after one single use (fast setup of new production facilities). Another expected advantage is a lower shear stress compared to classical stirred‐tank reactors, due to the gentle liquid motion in the rocking cellbag. This property would considerably reduce possible cell damage. The purpose of the present study is to investigate in a quantitative manner the key flow properties in Wave Bioreactors®, both numerically and experimentally. To describe accurately flow conditions and shear stress in Wave Bioreactors® using numerical simulations, it is necessary to compute the unsteady flow applying Computational Fluid Dynamics (CFD). Corresponding computations for two reactor scales (2 L and 20 L cellbags) are presented using the CFD code ANSYS‐FLUENT®. To describe correctly the free liquid surface, the present simulations employ the Volume of Fluid (VOF) method. Additionally, experimental measurements have been carried out to determine liquid level, flow velocity and liquid shear stress, which are used as a validation of the present CFD simulations. It is shown that the obtained flows stay in the laminar regime. Furthermore, the obtained shear stress levels are well below known threshold values leading to damage of animal cells. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Improved secretion of molecular chaperone‐assisted human IgG in silkworm, and no alterations in their N‐linked glycan structures
Authors: Dojima Takashi , Nishina Takuya , Kato Tatsuya , Uno Tsuyoshi , Yagi Hirokazu , Kato Koichi , Ueda Hiroshi , Park Enoch Y. 
Published: November 2009

AbstractHuman 29IJ6 IgG was expressed in silkworm using a Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid system. The mean amounts of 296IJ6 IgG produced in larval hemolymph and whole pupae were 30.1 μg/larva and 78.0 μg/pupa, respectively. The use of molecular chaperones including calreticulin (CRT), calnexin (CNX), and immunoglobulin heavy chain binding protein (BiP, GRP78) improved the production of 296IJ6 IgG secretion in the larvae fivefold. The total yield of recombinant 29IJ6 IgG was 239 μg/mL when coexpressed with CRT. However, the overexpression of molecular chaperones had negative effects on secretion. The N‐linked glycans of secreted 296IJ6 IgG in silkworm hemolymph were dominated by paucimannose structures. Small amounts of GlcNAc residues linked to the Manα1,3 branch were detected. When molecular chaperones were coexpressed, the compositions of N‐linked glycans in the IgG1 produced were unchanged compared with those produced without them. This suggests that N‐glycosylation is controlled by a regulatory function in the Golgi apparatus even though the post‐translational modification of 296IJ6 IgG was assisted by the coexpression of molecular chaperones. Therefore, if the glycosylation pathways that coexpress N‐acetylglucosaminyltransferase, galactosyltransferase, and sialyltransferase could be improved, silkworm larvae might prove a useful system for producing human antibodies. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Stabilization of invertase by molecular engineering
Authors: Tananchai Pattamawadee , Chisti Yusuf 
Published: November 2009

AbstractExtracellular invertase (EC 3.2.1.26) of Saccharomyces cerevisiae was stabilized against thermal denaturation by intermolecular and intramolecular crosslinking of the surface nucleophilic functional groups with diisocyanate homobifunctional reagents (OCN(CH2)nNCO) of various lengths (n = 4, 6, 8). Crosslinking with 1,4‐diisocyanatobutane (n = 4) proved most effective in enhancing thermostability. Stability was improved dramatically by crosslinking 0.5 mg/mL of protein with 30 μmol/mL of the reagent. Molecular engineering by crosslinking reduced the first‐order thermal denaturation constant at 60°C from 1.567 min−1 (for the native enzyme) to 0.437 min−1 (for the stabilized enzyme). Similarly, the best crosslinking treatment increased the activation energy for denaturation from 391 kJ mol−1 (for the native protein) to 466 kJ mol−1 (for the stabilized enzyme). Crosslinking was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010
A proteomic approach for identifying cellular proteins interacting with erythropoietin in recombinant Chinese hamster ovary cells
Authors: Kim Jee Yon , Kim Yeon‐Gu , Baik Jong Youn , Joo Eun Jin , Kim Young Hwan , Lee Gyun Min 
Published: November 2009

AbstractIdentification of the cellular proteins interacting with incompletely folded and unfolded forms of erythropoietin (EPO) in recombinant CHO (rCHO) cells leads to better insight into the possible genetic manipulation approaches for increasing EPO production. To do so, a pull‐down assay was performed with dual‐tagged (N‐terminal GST‐ and C‐terminal hexahistidine‐tagged) EPO expressed in E. coli as bait proteins and cell lysates of rCHO cells (DG44) as prey proteins. Cellular proteins interacting with dual‐tagged EPO were then resolved by two‐dimensional gel electrophoresis (2DE) and identified by MALDI‐TOF MS/MS. A total of 27 protein spots including glucose‐regulated protein 78 (GRP78) were successfully identified. Western blot analysis of GRP78 confirmed the results of the MS analyses. Taken together, a pull‐down assay followed by a proteomic approach is found to be an efficient means to identify cellular proteins interacting with foreign protein in rCHO cells. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Locating the arcuate line of Douglas: Is it of surgical relevance?
Authors: Mwachaka P.M. , Saidi H.S. , Odula P.O. , Awori K.O. , Kaisha W.O. 
Published: November 2009

AbstractVentral hernia formation is a common complication of rectus abdominis musculocutaneous flap harvest. The site and extent of harvest of the flap are known contributing factors. Therefore, an accurate location of the arcuate line of Douglas, which marks the lower extent of the posterior wall of the rectus sheath, may be relevant before harvesting the flap. This study is aimed at determining the position of the arcuate line in relation to anatomical landmarks of the anterior abdominal wall. Arcuate lines were examined in 80 (44 male, 36 female) subjects, aged between 18 and 70 years, during autopsies and dissection. The position of the arcuate line was determined in relation to the umbilicus, pubic symphysis, and intersections of rectus abdominis muscle. Sixty four (80.4%) cases had the arcuate line. In most cases (52), this line was located in the upper half of a line between the umbilicus and the pubic symphysis. Most males (93%) had the arcuate line, while more than a third of females did not have it. In all these cases, the line occurred bilaterally as a single arcade, constantly at the most distal intersection of the rectus abdominis muscle. Consequently, the arcuate line is most reliably marked superficially by the distal tendinous intersection of the rectus abdominis muscle. Harvesting of the muscle cranial to this point will minimize defects in the anterior abdominal wall that may lead to hernia formation. Clin. Anat. 23:84–86, 2010. © 2009 Wiley‐Liss, Inc.
Topographical anatomy of the transverse facial artery
Authors: Yang Hee‐Jun , Gil Young‐Chun , Lee Hye‐Yeon 
Published: November 2009

AbstractThe transverse facial artery (TFA) is found in the lateral face and supplies the parotid gland and duct, facial nerve, facial muscles, and skin. To better understand the cutaneous vascularization of the lateral face and to better characterize the topography and other anatomical features of the TFA, microsurgical dissection was performed in 44 cadavers. The number of TFAs present ranged from one to three, and a single TFA was most common (70.5%). The TFA originated from the superficial temporal artery at or above the level of crossing by the temporofacial trunk of the facial nerve in the parotid gland (57.6%). The TFA divided into superior and inferior trunks in the gland, and continued as emerging branch. The superior emerging branch emerged from the gland superior to the parotid duct and divided into many branches. It supplied the malar area, crossed the parotid duct, terminated as perforator, vasa nervorum, or artery to the parotid duct or muscle. The inferior trunk in 72.5% continued as emerging branch instead of terminating in the gland. TFAs were classified into four types; the most common type was Type A in which the superior and inferior emerging branches and the duct‐crossing branch were present. The mean number of perforators to the superficial cutaneous layer was 1.9. Most perforators extended from the superior emerging branches (77.9%). The most common perforating site was below the duct on the anterior third of the masseter muscle. In two cases, the TFA formed an anastomosis with the facial artery. Clin. Anat. 23:168–178, 2010. © 2009 Wiley‐Liss, Inc.
Adductor magnus: A post‐operative illustration of its dual nerve supply
Authors: Barrett Tristan , Arthurs Owen J. 
Published: November 2009

AbstractWe present a case in which MRI clearly demonstrated the function of the sciatic nerve by highlighting the complications of its involvement by disease and subsequent surgery. In this clinical case, the underlying diagnosis of a nerve sheath tumour had been established and treated surgically, and subsequent follow‐up imaging confirmed the expected features of sciatic nerve transection. Six months following the removal of the tumour, atrophy was seen in the muscle groups supplied by the branches of this nerve. This was manifested as muscle wasting and high signal on T1 and T2‐weighted MRI affecting the biceps femoris (short and long heads), semimembranosus, semitendinosus, and the hamstring (ischiocondylar) part of the adductor magnus, but the adductor part of the adductor magnus, supplied by the obturator nerve, was spared and appeared normal. Clin. Anat. 23:115–119, 2010. © 2009 Wiley‐Liss, Inc.
Cervical lymph nodes are found in direct relationship with the internal carotid artery: Significance for the lymphatic drainage of the brain
Authors: Clapham R. , O'Sullivan E. , Weller R.O. , Carare R.O. 
Published: November 2009

AbstractThe brain has no conventional lymphatics, but solutes injected into it drain along artery walls and reach lymph nodes in the neck. This study seeks to identify cervical lymph nodes related to the human internal carotid artery (ICA) that could act as the first regional lymph nodes for the brain. Bilateral dissections were carried out on four embalmed human heads, from the level of the carotid bifurcation in the neck, to the base of the skull. Lymph nodes from every specimen were processed for histological examination. A total of 51 deep cervical lymph nodes were identified: 12 lymph nodes (confirmed by histological examination) were observed to be in direct relationship with the ICA. These lymph nodes were found within the carotid sheath and had average diameters of 13.5 × 4.8 mm. Solutes and interstitial fluid from the brain may drain along the walls of cerebral arteries and reach these lymph nodes. They may be sites of stimulation of immune responses against antigens from the brain. Clin. Anat. 23:43–47, 2010. © 2009 Wiley‐Liss, Inc.
Anatomic position of the asterion in Kenyans for posterolateral surgical approaches to cranial cavity
Authors: Mwachaka P.M. , Hassanali J. , Odula P.O. 
Published: November 2009

AbstractThe asterion, defined as the junction between lambdoid, parietomastoid, and occipitomastoid sutures, has been used as a landmark in posterolateral approaches to the posterior fossa. Its reliability however has been put into question due to its population‐specific variability in position, using external palpable landmarks and its relation to the transverse–sigmoid sinus complex. This study aimed at determining the anatomic position of the asterion in a Kenyan population. Measurements from the asterion to the root of zygoma and the tip of mastoid process, respectively were taken on both left and right sides of 90 (51 male, 39 female) human skulls. The relation of the asterion to the transverse–sigmoid sinus junction was also determined. The distances on the right and left sides from the asterion to the root of the zygoma were 58.85 ± 2.50 mm and 58.44 ± 2.12 mm, respectively. The asterion was 47.89 ± 3.72 mm above the tip of mastoid process on the right side and 47.62 ± 2.87 mm on the left side. This point was significantly higher in males (48.36 ± 2.72 mm) than in females (46.62 ± 3.37 mm) with a P‐value of 0.041. Regarding its position from the transverse–sigmoid sinus junction, it was at the junction in 72 cases, below it in 17 cases (average 3.68 mm) and only one case had the asterion above this junction (2.57 mm). The asterion therefore can reliably be ascertained using the parameters from the root of the zygoma and the tip of the mastoid process. The safest approach would be posteroinferior to the asterion so as to avoid lacerating the transverse–sigmoid sinus complex. Clin. Anat. 23:30–33, 2010. © 2009 Wiley‐Liss, Inc.
The position of the mandibular canal and histologic feature of the inferior alveolar nerve
Authors: Kilic C. , Kamburoğlu K. , Ozen T. , Balcioglu H.A. , Kurt B. , Kutoglu T. , Ozan H. 
Published: November 2009

AbstractThe inferior alveolar nerve is the one of the large branches of the mandibular division of the trigeminal nerve. It is vulnerable during surgical procedures of the mandible. Despite its importance, no anatomical and histological examination has been conducted to provide a detailed cross‐sectional morphology of the mandibular canal according to dental status. Therefore, the present study aimed to identify the position of the mandibular canal through direct measurement and to determine the branches of the inferior alveolar nerve through histologic examination. The area between the anterior margin of the third molar and the anterior margin of the second premolar of dentulous, partially dentulous, and edentulous hemimandible specimens (n = 49) from 26 human cadavers was serially sectioned into seven segments, and specific distances were measured using digital calipers. Following this, 5‐μm cross‐sections were prepared along the mandibular canal and mental foramen, and examined by fluorescence microscopy. The mandibular canal was located at a mean distance of 10.52 mm above the inferior margin of the mandible. The mean maximum diameters of the mandibular canal, inferior alveolar nerve, inferior alveolar artery, and inferior alveolar vein were 2.52, 1.84, 0.42, and 0.58 mm, respectively. This study found that the inferior alveolar nerve often gives rise to several branches at each level (range 0–3). To minimize the risk of injury, knowledge of the small branches of the nerve and of the detailed findings regarding the position of the mandibular canal reported here should be considered when planning mandibular surgery, especially during implant placement. Clin. Anat. 23:34–42, 2010. © 2009 Wiley‐Liss, Inc.
Analysis of the Detailed Configuration of Hydrated Lanthanoid(III) Ions in Aqueous Solution and Crystalline Salts by Using K‐ and L3‐Edge XANES Spectroscopy
Authors: D'Angelo Paola , Zitolo Andrea , Migliorati Valentina , Persson Ingmar 
Published: November 2009

AbstractThe structural properties of the hydrated lanthanoid(III) ions in aqueous solution and in the isostructural trifluoromethanesulfonate salts have been investigated by a quantitative analysis of the X‐ray absorption near‐edge structure (XANES) spectra at the K‐ and L3‐edges. The XANES analysis has provided a clear description of the variation of lanthanoid(III) hydration properties across the series. It was found that all of the lanthanoid(III) hydration complexes retain a tricapped trigonal prism (TTP) geometry, and along the series two of the capping water molecules become less and less strongly bound, before finally, on average, one of them leaves the hydration cluster. This gives rise to an eight‐coordinated distorted bicapped trigonal prism with two different LnO capping distances for the smallest lanthanoid(III) ions. This systematic study has shown that for lanthanoid compounds more accurate structural information is obtained from the analysis of the L3‐edge than from K‐edge XANES data. Moreover, whereas the second hydration shells provide a detectable contribution to the L3‐edge XANES spectra of the lighter lanthanoid ions, the K‐edge spectra are insensitive to the more distant coordination spheres.
Design and Synthesis of a Highly Sensitive Off–On Fluorescent Chemosensor for Zinc Ions Utilizing Internal Charge Transfer
Authors: Hanaoka Kenjiro , Muramatsu Yasuaki , Urano Yasuteru , Terai Takuya , Nagano Tetsuo 
Published: November 2009

AbstractFluorescence imaging is a powerful tool for the visualization of biological molecules in living cells, tissue slices, and whole bodies, and is important for elucidating biological phenomena. Furthermore, zinc (Zn2+) is the second most abundant heavy metal ion in the human body after iron, and detection of chelatable Zn2+ in biological studies has attracted much attention. Herein, we present a novel, highly sensitive off–on fluorescent chemosensor for Zn2+ by using the internal charge transfer (ICT) mechanism. The rationale of our approach to highly sensitive sensor molecules is as follows. If fluorescence can be completely quenched in the absence of Zn2+, chemosensors would offer a better signal‐to‐noise ratio. However, it is difficult to quench the fluorescence completely before Zn2+ binding, and most sensor molecules still show very weak fluorescence in the absence of Zn2+. But even though the sensor shows a weak fluorescence in the absence of Zn2+, this fluorescence can be further suppressed by selecting an excitation wavelength that is barely absorbed by the Zn2+‐free sensor molecule. Focusing on careful control of ICT within the 4‐amino‐1,8‐naphthalimide dye platform, we designed and synthesized a new chemosensor (1) that shows a pronounced fluorescence enhancement with a blueshift in the absorption spectrum upon addition of Zn2+. The usefulness of 1 for monitoring Zn2+ changes was confirmed in living HeLa cells. There have been several reports on 4‐amino‐1,8‐naphthalimide‐based fluorescent sensor molecules. However, 1 is the first Zn2+‐sensitive off–on fluorescent sensor molecule that employs the ICT mechanism; most off–on sensor molecules for Zn2+ employ the photoinduced electron transfer (PeT) mechanism.
Bisthienylethenes Containing a Benzothiadiazole Unit as a Bridge: Photochromic Performance Dependence on Substitution Position
Authors: Zhu Weihong , Meng Xianle , Yang Yuheng , Zhang Qiong , Xie Yongshu , Tian He 
Published: November 2009

AbstractA conveniently synthesized photochromic compound, BTB‐1, containing an unprecedented six‐membered 2,1,3‐benzothiadiazole unit as the center ethene bridge, possesses good photochromic performance, with a high cyclization quantum yield and moderate fatigue resistance in solution or an organogel system. The fluorescence of BTB‐1 can be modulated by solvato‐ and photochromism. However, the analogue BTB‐2, in which the dimethylthiophene substituents are relocated to the 5,6‐positions of benzothiadiazole, does not show any detectable photochromism. To the best of our knowledge, this is the first example of six‐membered bridge bisthienylethenes (BTEs) in which the photochromism can be controlled by the substitution position. The photochromism difference is elucidated by the analysis of resonance structure, the Woodward–Hoffmann rule, and theoretical calculations on the ground‐state potential‐energy surface. In a well‐ordered single‐crystal state, BTB‐1 adopts a relatively rare parallel conformation, and forms an interesting two‐dimensional structure due to the presence of multiple directional intermolecular interactions, including CH⋅⋅⋅N and CH⋅⋅⋅S hydrogen‐bonding interactions, and π–π stacking interactions. This work contributes to several aspects for developing novel photochromic BTE systems with fluorescence modulation and performances controlled by substitution position in different states (solution, organogel, and single crystal).
Hydroxypyridinechromene and Pyridinechalcone: Two Coupled Photochromic Systems
Authors: Leydet Yoann , Parola A. Jorge , Pina Fernando 
Published: November 2009

AbstractSubstitution of the phenyl group in 2‐hydroxychalcones by a 4‐pyridine unit dramatically changes the network of chemical reactions of this compound: trans‐chalcone‐type (Ct), cis‐chalcone‐type (Cc), and a hemiketal (hydroxy‐4‐pyridinechromene) (B) and their protonated forms are formed, but the presence of a flavylium‐type cation could not be detected even at very acidic pH values. Moreover, whereas in 2‐phenyl‐2‐benzopyrylium compounds B and Cc are generally elusive species whose kinetic processes in aqueous solutions occur on the sub‐second timescale, in the present compound these species equilibrate on a timescale four orders of magnitude lower. Complete characterization of the equilibrium and kinetics of the reaction network could thus be achieved by 1H NMR spectroscopy and UV/Vis spectrophotometry. The network of chemical reactions exhibits cis–trans photoisomerization, as well as photochromism between the hemiketal and the chalcone‐type species. The irradiation of Ct in MeOH/H2O (1:1) at 365 nm produces B almost quantitatively through two consecutive photochemical reactions: Ct→Cc photoisomerization followed by Cc→B photo ring closure with a global quantum yield of 0.02. On the other hand, irradiation of B at 254 nm leads to a photostationary state composed by 80 % Ct and 20 % B, with a quantum yield of 0.21.
Difluorophosphoryl Nitrene F2P(O)N: Matrix Isolation and Unexpected Rearrangement to F2PNO
Authors: Zeng Xiaoqing , Beckers Helmut , Willner Helge , Neuhaus Patrik , Grote Dirk , Sander Wolfram 
Published: November 2009

AbstractTriplet difluorophosphoryl nitrene F2P(O)N (X3A′′) was generated on ArF excimer laser irradiation (λ=193 nm) of F2P(O)N3 in solid argon matrix at 16 K, and characterized by its matrix IR, UV/Vis, and EPR spectra, in combination with DFT and CBS‐QB3 calculations. On visible light irradiation (λ>420 nm) at 16 K F2P(O)N reacts with molecular nitrogen and some of the azide is regenerated. UV irradiation (λ=255 nm) of F2P(O)N (X3A′′) induced a Curtius‐type rearrangement, but instead of a 1,3‐fluorine shift, nitrogen migration to give F2PON is proposed to be the first step of the photoisomerization of F2P(O)N into F2PNO (difluoronitrosophosphine). Formation of novel F2PNO was confirmed with 15N‐ and 18O‐enriched isotopomers by IR spectroscopy and DFT calculations. Theoretical calculations predict a rather long PN bond of 1.922 Å [B3LYP/6‐311+G(3df)] and low bond‐dissociation energy of 76.3 kJ mol−1 (CBS‐QB3) for F2PNO.