bluuebunny/crossref_metadata_2025 huggingface dataset:
The Fish in the Turtle: On the Functionality of the Oropharynx in the Common Musk Turtle Sternotherus odoratus (Chelonia, Kinosternidae) Concerning Feeding and Underwater Respiration
Authors: Heiss Egon , Natchev Nikolay , Beisser Christian , Lemell Patrick , Weisgram Josef
Published: May 2010

In tetrapods, the oropharyngeal cavity and its anatomical structures are mainly, but not exclusively, responsible for the uptake and intraoral transport of food. In this study, we provide structural evidence for a second function of the oropharynx in the North American common musk turtle, Sternotherus odoratus, Kinosternidae: aquatic gas exchange. Using high‐speed video, we demonstrate that S. odoratus can grasp food on land by its jaws, but is afterward incapable of lingual based intraoral transport; food is always lost during such an attempt. Scanning electron microscopy and light microscopy reveal that the reason for this is a poorly developed tongue. Although small, the tongue bears a variety of lobe‐like papillae, which might be misinterpreted as an adaptation for terrestrial food uptake. Similar papillae also cover most of the oropharynx. They are highly vascularized as shown by light microscopy and may play an important role in aquatic gas exchange. The vascularization of the oropharyngeal papillae in S. odoratus is then compared with that in Emys orbicularis, an aquatic emydid with similar ecology but lacking the ability of underwater respiration. Oropharyngeal papillae responsible for aquatic respiration are also found in soft‐shelled turtles (Trionychidae), the putative sister group of the kinosternids. This trait could therefore represent a shared, ancestral character of both groups involving advantages in the aquatic environment they inhabit. Anat Rec 293:1416–1424, 2010. © 2010 Wiley‐Liss, Inc.
Histological Determination of the Areas Enriched in Cholinergic Terminals and m2 and m3 Muscarinic Receptors in the Mouse Central Auditory System
Authors: Hamada Satoko , Houtani Takeshi , Trifonov Stefan , Kase Masahiko , Maruyama Masato , Shimizu Jun‐Ichi , Yamashita Toshio , Tomoda Koichi , Sugimoto Tetsuo
Published: May 2010

Cholinergic projections to auditory system are vital for coupling arousal with sound processing. Systematic search with in situ hybridization and immunohistochemistry indicated that the ventral nucleus of the medial geniculate body and the nucleus of the brachium of the inferior colliculus constituted cholinergic synaptic sites in the brainstem auditory system, containing a significant number of cholinergic axon terminals and m2 receptor‐expressing cell bodies. Anat Rec 293:1393–1399, 2010. © 2010 Wiley‐Liss, Inc.
Some learning objects to explain Kepler's laws
Authors: Benítez Julio , Giménez Marcos H. , Hueso José L. , Martínez Eulalia , Riera Jaime
Published: May 2010

In this paper, we present some learning objects for the study of Kepler's laws that graphically show the orbits and the movements of various planets. One of them shows the orbit of a planet from the point of view of a fixed planet, showing that the orbit is quite involved. No differentials equations are required, but only elementary vector calculus. The learning objects have been implemented in Matlab. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 1–7, 2013
Z‐transform and its application to development of scientific simulation algorithms
Authors: Fazarinc Zvonko
Published: May 2010

Engineers and educators find in computer simulations a powerful substitute for inability of calculus to produce closed form solutions to modern problems. But the validity of quasi‐closed‐form solutions produced by computers remains suspect. While no magic test exists, pieces of algorithms can individually be examined by the Z‐transform [E. I. Jury, Sampled‐data control systems, John Wiley & Sons, 1958]. Two examples from engineering and three from education are presented. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 75–88, 2013
Two‐photon absorption circular‐linear dichroism on axial enantiomers
Authors: Toro Carlos , De Boni Leonardo , Lin Na , Santoro Fabrizio , Rizzo Antonio , Hernandez Florencio E.
Published: May 2010

We report on the experimental‐theoretical analysis of degenerated two‐photon absorption circular‐linear dichroism (2PA‐CLD) in (S)‐(−)‐1,1′‐bi(2‐naphthol) and (R)‐(+)‐1,1′‐bi(2‐naphthol) dissolved in THF. 2PA‐CLD reveals similarities and differences between optical polarization states for the different enantiomers. These results unveil the potential applications of 2PA‐CLD for the study and identification of chiral molecules with active and pivotal role in biological systems and the systematic design of chiral photonic structures. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
Applications of the Cartesian coordinate tensor transfer technique in the simulations of vibrational circular dichroism spectra of oligonucleotides
Authors: Andrushchenko Valery , Bouř Petr
Published: May 2010

The application of the Cartesian coordinate tensor transfer (CCT) technique for simulations of the IR absorption and vibrational circular dichroism (VCD) spectra of relatively large nucleic acid fragments is demonstrated on several case studies. The approach is based on direct ab initio calculations of atomic tensors, determining molecular properties, for relatively small fragments, and subsequent transfer of these tensors to the larger systems in Cartesian coordinates. This procedure enables precise computations of vibrational spectra for large biomolecular systems, currently with up to several thousands of atoms. The versatile ability of the CCT methods is emphasized on the examples of VCD and IR absorption spectra calculations for B‐ and Z‐forms of DNA, single‐, double‐, and triple‐stranded RNA helices and DNA structures with different base content and sequences. The development and recent improvements of the methodology are followed, including utilization of the constrained normal mode optimization (NMO) strategy and combined quantum mechanics and molecular dynamics simulations. Advantages, drawbacks, and recommendations for future improvements of the CCT method as applied to nucleic acid spectra calculations are discussed. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
Improved survival in patients with early stage low‐grade follicular lymphoma treated with radiation
Authors: Pugh Thomas J. , Ballonoff Ari , Newman Francis , Rabinovitch Rachel
Published: May 2010

BACKGROUND:

External beam radiation therapy (RT) is the standard treatment for stage I‐II, grade 1‐2 follicular lymphoma. Because of an indolent natural history, some advocate alternative management strategies, including watchful waiting for this disease. The relative improvement in outcomes for patients treated with and without RT has never been tested in randomized trials.

METHODS:

The Surveillance, Epidemiology, and End Results database was queried for adult patients with stage I‐II, grade 1‐2 follicular lymphoma diagnosed from 1973 to 2004. Retrievable patient data included age, sex, race, stage, extranodal disease, and treatment with RT within the first year after diagnosis. Actuarial overall survival (OS) and disease‐specific survival (DSS) were analyzed.

RESULTS:

A total of 6568 patients were identified. DSS at 5, 10, 15, and 20 years in the RT group was 90%, 79%, 68%, and 63% versus 81%, 66%, 57%, and 51% in the no RT group (hazard ratio [HR], 0.61; 95% confidence interval [CI], 0.55‐0.68;P< .0001). OS at 5, 10, 15, and 20 years in the RT group was 81%, 62%, 45%, and 35% versus 71%, 48%, 34%, and 23% in patients not receiving RT (HR, 0.68; 95% CI, 0.63‐0.73;P< .0001). On multivariate analysis, upfront RT remained independently associated with improved DSS (P< .0001, Cox HR, 0.65; 95% CI, 0.57‐0.72) and OS (P< .0001; Cox HR, 0.73; 95% CI, 0.67‐0.79). Lymphoma was the most common cause of death (52%). Only 34% of patients received upfront RT.

CONCLUSIONS:

Upfront RT was associated with improved DSS and OS compared with alternate management approaches, a benefit that persisted over time. This benefit suggests that watchful waiting with administration of salvage therapies on progression/relapse do not compensate for inadequate initial definitive treatment. Although it is the standard of care for this disease, RT for early stage low‐grade follicular lymphoma is greatly underused in the US population; increased use of upfront RT could prevent thousands of deaths from lymphoma in these patients. Cancer 2010. © 2010 American Cancer Society.
Germ cell‐specific heat shock protein 70‐2 is expressed in cervical carcinoma and is involved in the growth, migration, and invasion of cervical cells
Authors: Garg Manoj , Kanojia Deepika , Saini Shikha , Suri Sushma , Gupta Anju , Surolia Avadhesha , Suri Anil
Published: May 2010

BACKGROUND:

Cervical cancer is a major cause of death among women worldwide, and the most cases are reported in the least developed countries. Recently, a study on DNA microarray gene expression analysis demonstrated the overexpression of heat shock protein 70‐2 (HSP70‐2) in cervical carcinoma cells (HeLa). The objective of the current study was to evaluate the association between HSP70‐2 expression in cervical carcinogenesis and its potential role in various malignant properties that result in disease progression.

METHODS:

HSP70‐2 expression was examined in various cervical cancer cell lines with different origins and in clinical cervical cancer specimens by reverse transcriptase‐polymerase chain reaction (RT‐PCR), flow cytometry, and immunohistochemistry (IHC) analyses. A plasmid‐based, short‐hairpin RNA approach was used specifically to knock down the expression of HSP70‐2 in cervical tumor cells in vitro and in vivo to examine the role of HSP70‐2 on various malignant properties.

RESULTS:

RT‐PCR and IHC analyses revealed HSP70‐2 expression in 86% of cervical cancer specimens. Furthermore, knockdown of HSP70‐2 expression significantly reduced cellular growth, colony formation, migration, and invasion in vitro and reduced tumor growth in vivo. A significant association of HSP70‐2 gene and protein expression was observed among the various tumor stages (P = .046) and different grades (P = .006), suggesting that HSP70‐2 expression may be an indicator of disease progression.

CONCLUSIONS:

The current findings suggested that HSP70‐2 may play an important role in disease progression in cervical carcinogenesis. Patients who had early stage disease and low‐grade tumors had HSP70‐2 expression, supporting its potential role in early detection and aggressive treatment modalities for cervical cancer management. Cancer 2010. © 2010 American Cancer Society.
Outcome of patients with myelodysplastic syndrome after failure of decitabine therapy
Authors: Jabbour Elias , Garcia‐Manero Guillermo , Batty Nicolas , Shan Jenny , O'Brien Susan , Cortes Jorge , Ravandi Farhad , Issa Jean‐Pierre , Kantarjian Hagop
Published: May 2010

BACKGROUND:

The prognosis of patients with myelodysplastic syndrome (MDS) after decitabine failure is not known.

METHODS:

Data from 87 patients with MDS (n = 67) and chronic myelomonocytic leukemia (n = .20) after failure of decitabine regimens were reviewed.

RESULTS:

After a median follow‐up of 21 months from decitabine failure, 13 (15%) patients remained alive; the median survival was 4.3 months, and the estimated 12‐month survival rate was 28%. The estimated 12‐month survival rates were 27%, 33%, and 33%, respectively, for patients with high‐risk, intermediate‐2‐risk, and intermediate‐1‐risk disease (P = .99) by the International Prognostic Scoring System. The estimated 12‐month survival rates were 100%, 54%, 41%, and 18%, respectively, for patients with low‐risk, intermediate‐1‐risk, intermediate‐2‐risk, and high‐risk disease according to The University of Texas M. D. Anderson Cancer Center risk model (P = .01).

CONCLUSIONS:

The outcome of patients after decitabine failure is poor and appears to be predictable after decitabine failure. Cancer 2010. © 2010 American Cancer Society.
Theoretical Investigation on the Origin of Yellow‐Green Firefly Bioluminescence by Time‐Dependent Density Functional Theory
Authors: Min Chun‐Gang , Ren Ai‐Min , Guo Jing‐Fu , Zou Lu‐Yi , Goddard John D. , Sun Chia‐Chung
Published: May 2010

The question whether the emitter of yellow‐green firefly bioluminescence is the enol or keto‐constrained form of oxyluciferin (OxyLH2) still has no definitive answer from experiment or theory. In this study, Arg220, His247, adenosine monophosphate (AMP), Water324, Phe249, Gly343, and Ser349, which make the dominant contributions to color tuning of the fluorescence, are selected to simulate the luciferase (Luc) environment and thus elucidate the origin of firefly bioluminescence. Their respective and compositive effects on OxyLH2 are considered and the electronic absorption and emission spectra are investigated with B3LYP, B3PW91, and PBE1KCIS methods. Comparing the respective effects in the gas and aqueous phases revealed that the emission transition is prohibited in the gas phase but allowed in the aqueous phase. For the compositive effects, the optimized geometry shows that OxyLH2 exists in the keto(−1) form when Arg220, His247, AMP, Water324, Phe249, Gly343, and Ser349 are all included in the model. Furthermore, the emission maximum wavelength of keto(−1)+Arg+His+AMP+H2O+Phe+Gly+Ser is close to the experimental value (560 nm). We conclude that the keto(−1) form of OxyLH2 is a possible emitter which can produce yellow‐green bioluminescence because of the compositive effects of Arg220, His247, AMP, Water324, Phe249, Gly343, and Ser349 in the luciferase environment. Moreover, AMP may be involved in enolization of the keto(−1) form of OxyLH2. Water324 is indispensable with respect to the environmental factors around luciferin (LH2).
The complexity of partition tasks
Authors: Eesponda Fernando , Vera‐Cruz Matías , Tarrasó Jorge , Morales Marco
Published: May 2010

In this article, we introduce the partition task problem class along with a complexity measure to evaluate its instances and a performance measure to quantify the ability of a system to solve them. We explore, via simulations, some potential applications of these concepts and present some results as examples that highlight their usefulness in policy design scenarios, where the optimal number of elements in a partition or the optimal size of the elements in a partition must be determined. © 2010 Wiley Periodicals, Inc. Complexity 16: 56–64, 2010
Oxidative Depolymerization of Lignin in Ionic Liquids
Authors: Stärk Kerstin , Taccardi Nicola , Bösmann Andreas , Wasserscheid Peter
Published: May 2010

Beech lignin was oxidatively cleaved in ionic liquids to give phenols, unsaturated propylaromatics, and aromatic aldehydes. A multiparallel batch reactor system was used to screen different ionic liquids and metal catalysts. Mn(NO3)2 in 1‐ethyl‐3‐methylimidazolium trifluoromethanesulfonate [EMIM][CF3SO3] proved to be the most effective reaction system. A larger scale batch reaction with this system in a 300 mL autoclave (11 g lignin starting material) resulted in a maximum conversion of 66.3 % (24 h at 100 °C, 84×105 Pa air). By adjusting the reaction conditions and catalyst loading, the selectivity of the process could be shifted from syringaldehyde as the predominant product to 2,6‐dimethoxy‐1,4‐benzoquinone (DMBQ). Surprisingly, the latter could be isolated as a pure substance in 11.5 wt % overall yield by a simple extraction/crystallization process.
Direct space vector PWM strategy for matrix converters with reduced number of switching transitions
Authors: Tadano Yugo , Hamada Shizunori , Urushibata Shota , Nomura Masakatsu , Sato Yukihiko , Ishida Muneaki
Published: May 2010

This paper proposes a novel “Direct Space Vector PWM (Direct SVPWM)” strategy based on the direct AC/AC conversion approach for three‐phase to three‐phase matrix converters. This method allows the sinusoidal input and output waveforms as a major premise, and gives top priority to the improvement of output control performance in motor drive applications, such as providing maximum riding comfort in elevators, etc. Output voltage harmonics, switching losses, and common‐mode voltages can be reduced across the entire voltage region. In addition, the switching count can be reduced even further by fully utilizing the output current detection value. Direct space vectors are first defined, and the method of selecting space vectors is described. Next, the PWM duty calculation technique is explained. Finally, the validity of the proposed method is demonstrated by comparison with the conventional virtual indirect method based on experimental and analytical results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(3): 52–63, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20953
Importance of TLR2 in the direct response of T lymphocytes to Schistosoma mansoni antigens
Authors: Burton Oliver T. , Gibbs Sarah , Miller Nigel , Jones Frances M. , Wen Li , Dunne David W. , Cooke Anne , Zaccone Paola
Published: May 2010

The immunomodulatory effect of Schistosoma mansoni antigens has often been attributed to interaction with PRR expressed on APC. Our previous work has shown that S. mansoni‐soluble egg antigen (SEA) can induce, together with a Th2 response, TGF‐β‐dependent Foxp3 expression in naïve CD4+ T cells from NOD mice. We found that SEA can directly upregulate the expression of surface‐bound TGF‐β in purified CD4+ T cells in the absence of accessory cell interactions. In this study, we show that the C‐type lectin receptors DEC‐205 and galectin‐3 were involved in the direct interaction between S. mansoni antigens and CD4+ T cells. SEA was able to enhance CD4+ T‐cell secretion of bioactive TGF‐β in response to TLR2 ligand stimulation, in the absence of APC. We also show that TLR2 expressed on CD4+ T cells was important for the Foxp3 expression induced by SEA.
(GTI‐tcbiomass) life‐cycle assessment of the BTO®‐process (biomass‐to‐oil) with combined heat and power generation
Authors: Faix Axel , Schweinle Jörg , Schöll Stefan , Becker Gero , Meier Dietrich
Published: May 2010

A life cycle assessment study of the biomass‐to‐oil (BTO®) process based on the fast ablative pyrolysis of wood chips from forest residues has been performed. The planned system consists of eight pyrolyzers with a throughput of 6 tpd each. The bio‐oil will be burnt in eight modified diesel engines with a capacity of 315 kWhel each. The results were compared with a reference system (fossil diesel‐fueled CHP). The comparison is made for the production of 1 kWh of electrical energy (kWhel) and shows significant differences for global warming potential (GWP100: −87.7%), eutrophication potential (EP: +23.2%), acidification potential (AP: −44.6%), photochemical ozone creation potential (POCP: −63.6%), and ozone depletion potential (ODP: −92.4%). The results of the BTO‐CHP‐system show lower environmental impact values in all environmental impact categories except for the EP‐value, which exceeds the reference due to the application of bio‐oil additives derived from agricultural production. © 2010 American Institute of Chemical Engineers Environ Prog, 2010
Two New Acylated Tridesmosidic Saponins from Astragalus armatus
Authors: Semmar Nabil , Tomofumi Miyamoto , Mrabet Yassine , Lacaille‐Dubois Marie‐Aleth
Published: May 2010

Two new tridesmosidic glycosides of (3β,6α,16β,20R,24S)‐20,24‐epoxycycloartane‐3,6,16,25‐tetrol (=cycloastragenol), armatosides I and II (1 and 2, resp.), were isolated from the roots of Astragalus armatus (Fabaceae) as well as the known bidesmosidic glycosides of cycloastragenol, trigonoside II (3) and trojanoside H (4). Their structures were elucidated as (3β,6α,16β,20R,24S)‐3‐O‐(2,3‐di‐O‐acetyl‐β‐D‐xylopyranosyl)‐20,24‐epoxy‐25‐O‐β‐D‐glucopyranosyl‐6‐O‐β‐D‐xylopyranosylcycloartane‐3,6,16,25‐tetrol (1), and (3β,6α,16β,20R,24S)‐3‐O‐(2‐O‐acetyl‐β‐D‐xylopyranosyl)‐20,24‐epoxy‐25‐O‐β‐D‐glucopyranosyl‐6‐O‐β‐D‐xylopyranosylcycloartane‐3,6,16,25‐tetrol (2). These structures were established by extensive NMR and MS analyses and by comparison with literature data.
A Novel One‐Pot Synthesis of Substituted Quinolines
Authors: Sabbaghan Maryam , Yavari Issa , Hossaini Zinatossadat , Souri Sanaz
Published: May 2010

A synthesis of quinoline derivatives is described via reaction between ethyl bromopyruvate (=ethyl 3‐bromo‐2‐oxopropanoate), acetylenedicarboxylate, and isatin (=1H‐indole‐2,3‐dione) in the presence of NaH as a base. Also, these reactions were performed without ethyl bromopyruvate. The reaction in the presence of ethyl bromopyruvate provides regioselectively a quinoline with the ethyl ester group in 4‐position. In the absence of ethyl bromopyruvate, the reaction leads to functionalized quinolines with the same ester groups in 2‐, 3‐, and 4‐positions.
Litseaglutinan A and Lignans from Litsea glutinosa
Authors: Pan Jian‐Yu , Zhang Si , Wu Jun , Li Qing‐Xin , Xiao Zhi‐Hui
Published: May 2010

A new abscisic acid derivative, named litseaglutinan A (1), and a new arylnaphthalene‐type lignan, (7′S,8R,8′S)‐4,4′,9‐trihydroxy‐3,3′,5‐trimethoxy‐9′‐O‐β‐D‐xylopyranosyl‐2,7′‐cyclolignan (2), were isolated from the AcOEt extract of Litsea glutinosa, together with nine known lignans. Their structures were established by spectroscopic methods.
New Pentacyclic Cucurbitane Glucosides from the Fruits of Citrullus colocynthisSchrad.
Authors: Nayab Durey , Perveen Shagufta , Ahmed Zaheer , Malik Abdul
Published: May 2010

Colocynthins A–C (1–3, resp.), new pentacyclic cucurbitane type triterpene glucosides, have been isolated from the AcOEt‐soluble fraction of the fruits of Citrullus colocynthis, along with three known compounds, β‐sitosterol 3‐O‐β‐D‐glucopyranoside, elaterinide, and bryoamaride. Their structures were determined on the basis of 1H‐ and 13C‐NMR spectra, DEPT, and COSY, NOESY, HMQC, and HMBC experiments.
Two Novel Sesquiterpenoids from the Roots of Ferula ferulaeoides (Steud.) Korov.
Authors: Hu Yue , Li Xiao‐Dong , Li Guo‐Yu , Li Ning , Zuo Wen‐Jian , Zeng Yi‐Mei , Meng He , Li Xian , Wang Jin‐Hui
Published: May 2010

Two new sesquiterpenoids, ferulactones A and B (1 and 2, resp.), have been isolated from the roots of Ferula ferulaeoides (Steud.) Korov. Their structures and relative configurations were established by analysis of spectroscopic data. Their absolute configuration was assigned by application of the CD technique.
Formation of 6‐Methyl‐7,11‐diphenylheptaleno[1,2‐c]furanones
Authors: Jin Xudong , Linden Anthony , Hansen Hans‐Jürgen
Published: May 2010

The dehydrogenation reaction of a mixture of heptalene‐1,2‐ and heptalene‐4,5‐dimethanols 4a and 4b with basic MnO2 in AcOEt at room temperature led to the formation of the corresponding heptaleno[1,2‐c]furan‐1‐one 6a and heptaleno[1,2‐c]furan‐3‐one 7a (Scheme 2). Both products can be isolated by chromatography on silica gel. The methylenation of the furan‐3‐one 7a with 1 mol‐equiv. of Tebbe's reagent at −25 to −30° afforded the 2‐isopropenyl‐5‐methylheptalene‐1‐methanol 9a, instead of the expected 3,6‐dimethylheptaleno[1,2‐c]furan 8 (Scheme 3). Also, the treatment of 7a with Takai's reagent did not lead to the formation of 8. On standing in solution at room temperature, or more rapidly on heating at 60°, heptalene 9a undergoes a reversible double‐bond shift (DBS) to 9b with an equilibrium ratio of 1 : 1.
Effects of chronic estrogen treatment on modulating age-related bone loss in female mice
Authors: Syed Farhan A , Mödder Ulrike IL , Roforth Matthew , Hensen Ira , Fraser Daniel G , Peterson James M , Oursler Merry Jo , Khosla Sundeep
Published: May 2010

While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age-related bone loss, we sham-operated, ovariectomized, or ovariectomized and estrogen-replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six-month-old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham-operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen-treated mice did not prevent age-related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age-related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham-operated mice. As compared with cells from young mice, lin– cells from aged/sham-operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age-related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.
Fat mass accumulation compromises bone adaptation to load in finnish women: A cross-sectional study spanning three generations
Authors: Xu Leiting , Nicholson Patrick , Wang Qing-Ju , Wang Qin , Alén Markku , Cheng Sulin
Published: May 2010

Body weight and lean mass correlate with bone mass, but the relationship between fat mass and bone remains elusive. The study population consisted of 396 girls and 138 premenopausal mothers and 114 postmenopausal grandmothers of these girls. Body composition and tibial length were assessed using dual-energy X-ray absorptiometry (DXA), and bone traits were determined at the tibia using peripheral quantitative computed tomography (pQCT) in the girls at the ages of 11.2 ± 0.8, 13.2 ± 0.9, and 18.3 ± 1.0 years and in the mothers (44.7 ± 4.1 years) and grandmothers (70.7 ± 6.3 years). The values of relative bone strength index (RBSI), an index reflecting the ratio of bone strength to the load applied on the tibia, were correlated among family members (all p < .05). The mean values of RBSI were similar among 11- and 18-year-old girls and premenopausal women but significantly lower in 13-year-old girls and postmenopausal women. However, in each age group, subjects in the highest BMI tertiles had the lowest RBSI values (all p < .01). RBSI was inversely associated with body weight (all p < .01), indicating a deficit in bone strength relative to the applied load from greater body weight. RBSI was inversely associated with fat mass (all p < .001) across age groups and generations but remained relatively constant with increasing lean mass in girls and premenopausal women (all p > .05), indicating that the bone-strength deficit was attributable to increased fat mass, not lean mass. Moreover, the adverse effect of fat mass was age-dependent, with every unit increase in fat mass associated with a greater decrease in RBSI in pre- and postmenopausal women than in girls (all p < .001). This is largely due to the different capacity of young and adult bones to increase diaphyseal width by periosteal apposition in response to increased load. In summary, increasing body weight with fat accumulation is accompanied by an age-dependent relative bone-strength deficit in women because the beneficial effects of increased fat mass on bone, if any, do not compensate for the mechanical burden that it imposes. © 2010 American Society for Bone and Mineral Research.
Molecular silencing of Twist1 enhances osteogenic differentiation of murine mesenchymal stem cells: Implication of FGFR2 signaling
Authors: Miraoui Hichem , Severe Nicolas , Vaudin Pascal , Pagès Jean‐Christophe , Marie Pierre J.
Published: May 2010

The capacity of mesenchymal stem cells (MSCs) to differentiate into functional osteoblasts is tightly controlled by transcription factors that trigger osteoblast commitment and differentiation. The role of Twist1, a basic helix‐loop‐helix (bHLH) transcription factor, in osteogenic differentiation of MSCs remains unclear. Here we investigated the role of Twist1 in the osteogenic differentiation program of murine C3H10T1/2 mesenchymal cells. We showed that molecular silencing of Twist1 using short hairpin RNA (shRNA) expression moderately increased C3H10T1/2 cell proliferation and had no effect on cell survival. In contrast, Twist1 silencing enhanced osteoblast gene expression and matrix mineralization in vitro. Biochemical analyses revealed that Twist1 silencing increased the expression of FGFR2 protein level, which was reduced by a mutant Runx2. Consistent with this finding, Twist1 silencing increased ERK1/2 and PI3K signaling. Moreover, molecular or pharmacological inhibition of FGFR2 or of ERK1/2 and PI3K signaling partly abolished the increased osteoblast gene expression induced by Twist1 silencing in C3H10T1/2 cells. These results reveal that Twist1 silencing upregulates osteoblast differentiation of murine mesenchymal cells in part via activation of FGFR2 expression and downstream signaling pathways, which provides novel insights into the molecular signals by which this transcription factor regulates the osteogenic differentiation program in MSCs. J. Cell. Biochem. 110: 1147–1154, 2010. Published 2010 Wiley‐Liss, Inc.
Poly (ADP‐ribose) polymerase‐1 binds to BCL2 major breakpoint region and regulates BCL2 expression
Authors: Yang Nan , Gong Feiran , Sun Luan , Yang Dapeng , Han Xiao , Ma Changyan , Sun Yujie
Published: May 2010

BCL2, originally identified as a proto‐oncogene in B‐cell lymphoma, is a key regulator of apoptosis. Although it is more than 200 kb in length, at least 70% of the t(14;18) translocation in follicular lymphomas occurs at the BCL2 major breakpoint region (mbr), located in the 3′‐untranslated region (3'‐UTR). We have previously found that the mbr is a regulatory element which positively regulates BCL2 expression and this regulatory function was closely associated with SATB1, which binds to a 37 bp mbr (37 mbr) in the 3′‐end of the mbr directly. However, the precise molecular mechanisms by which the mbr regulates gene expression are not fully understood. In this study, we purified Poly(ADP‐ribose) polymerase‐1 (PARP‐1) from the DNA–protein complexes formed by 37 mbr in Jurkat cells and demonstrated that PARP‐1 participates in the 37 mbr–protein complex's formation in vitro and in vivo. Functional analysis showed that overexpression of PARP‐1 decreases 37 mbr regulatory function and BCL2 expression. Conversely, knockdown of PARP‐1 with RNAi increases BCL2 expression. Taken together, the present findings indicate that PARP‐1 is a component of BCL2 37 mbr–protein complexes, and PARP‐1 is involved in the regulation of BCL2 expression. These findings are helpful in understanding the regulatory mechanisms of BCL2 expression. J. Cell. Biochem. 110: 1208–1218, 2010. Published 2010 Wiley‐Liss, Inc.
Chemical reactivity predictions: Use of data mining techniques for analyzing regioselective azidolysis of epoxides
Authors: Borghini Alice , Crotti Paolo , Pietra Daniele , Favero Lucilla , Bianucci Anna Maria
Published: May 2010

Azidolysis of epoxides followed by reduction of the intermediate azido alcohols constitutes a valuable synthetic tool for the construction of β‐amino alcohols, an important chemical functionality occurring in many biologically active compounds of natural origin. However, depending on conditions under which the azidolysis is carried out, two regioisomeric products can be formed, as a consequence of the nucleophilic attack on both the oxirane carbon atoms. In this work, predictive models for quantitative structure‐reactivity relationships were developed by means of multiple linear regression, k‐nearest neighbor, locally weighted regression, and Gaussian Process regression algorithms. The specific nature of the problem at hand required the creation of appropriate new descriptors, able to properly reflect the most relevant features of molecular moieties directly involved in the opening process. The models so obtained are able to predict the regioselectivity of the azidolysis of epoxides promoted by sodium azide, in the presence of lithium perchlorate, on the basis of steric hindrance, and charge distribution of the substituents directly attached to the oxirane ring. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
A density‐functional study of the phase diagram of cementite‐type (Fe,Mn)3C at absolute zero temperature
Authors: Von Appen Jörg , Eck Bernhard , Dronskowski Richard
Published: May 2010

The phase diagram of (Fe1−x Mnx)3C has been investigated by means of density‐functional theory (DFT) calculations at absolute zero temperature. The atomic distributions of the metal atoms are not random‐like as previously proposed but we find three different, ordered regions within the phase range. The key role is played by the 8d metal site which forms, as a function of the composition, differing magnetic layers, and these dominate the physical properties. We calculated the magnetic moments, the volumes, the enthalpies of mixing and formation of 13 different compositions and explain the changes of the macroscopic properties with changes in the electronic and magnetic structures by means of bonding analyses using the Crystal Orbital Hamilton Population (COHP) technique. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
Morphology of epithelial cells lining the digestive tract of the giant keyhole limpet, Megathura crenulata (Mollusca; Vetigastropoda)
Authors: Martin Gary G. , Bessette Tracy , Martin Alanna , Cotero Renae , Vumbaco Kathryn , Oakes Christopher
Published: May 2010

To understand the digestive functions in the giant keyhole limpet, it is important to know the types of cells present in each region of the gut and their roles in the secretion of digestive enzymes and absorption of nutrients. This study describes the morphology of cells lining the entire gut and identifies sites that may be secreting materials to aid digestion. Previous studies involving electron microscopy and enzyme analysis have focused on the salivary and digestive glands of several gastropods. Studies on the rest of the gut tract typically include only histological descriptions of the epithelia and although several types of cells have been described, they appear very similar. The purpose of this study is to determine if electron microscopy can provide better insights into the functions of cells in these poorly studied regions of the gut. Our ultrastructural observations suggest that only two types of cells, mucus secreting cells and apocrine secretory cells make up the epithelium in the esophagus, style sac, and intestine. These regions account for 85% of the length of the entire digestive tract. Apocrine secretory cells contain pigment granules, bear cilia, and/or microvilli at their apices, and release product into the gut lumen via apocrine secretion. This suggests that the secretory processes involved with digestion are occurring in most regions of the gut and that apocrine secretion is the primary mode by which materials are introduced into the gut lumen. The lips, salivary glands, stomach, and digestive gland lack apocrine secretory cells and the epithelial cells are similar to those described in other gastropods. J. Morphol. 271:1134–1151, 2010. © 2010 Wiley‐Liss, Inc.
Inhibition of uPAR and uPA reduces invasion in papillary thyroid carcinoma cells
Authors: Nowicki Theodore S. , Kummer Nicolas T. , Iacob Codrin , Suslina Nina , Schaefer Steven , Schantz Stimson , Shin Edward , Moscatello Augustine L. , Tiwari Raj K. , Geliebter Jan
Published: May 2010

Objectives/Hypothesis:

We analyzed the expression of urokinase plasminogen activator (uPA) and its receptor (uPAR) in papillary thyroid carcinoma (PTC) and normal thyroid tissue and examined in vitro how uPA and uPAR contribute to an invasive/metastatic phenotype, and the functional consequences of inhibiting this system.

Study Design:

Retrospective chart review of PTC patients, followed by prospective study using previously obtained patient tissue and PTC cellular models.

Methods:

uPA and uPAR RNA and protein levels were analyzed in PTC patient tissue samples, PTC and normal thyroid tissue culture cells, and conditioned media (CM) using quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) and/or Western blotting. The plasminogen‐activating ability of CM was examined using dark‐quenched casein fluorimetry and casein‐plasminogen gel zymography. The invasive potentials of the PTC and normal thyroid epithelial cell lines were assessed using an in vitro cellular invasion/migration system.

Results:

uPA and uPAR RNA and protein levels were increased in PTC patient samples and PTC cells relative to controls. uPA and uPAR RNA were also significantly higher in patients with metastatic disease. Casein‐plasminogen zymography and Western blotting demonstrated increased active uPA secreted by PTC cells compared with normal thyroid cells. Fluorimetric assays revealed that the PTC cells' CM was able to activate plasminogen, resulting in measurable casein hydrolysis. This casein hydrolysis was prevented by the addition of several specific uPA inhibitors. Finally, the in vitro invasion phenotypes of PTC cells were augmented by the addition of plasminogen, and this augmentation was reversed by inhibitory anti‐uPA and anti‐uPAR antibodies.

Conclusions:

These data provide new functional evidence of the uPA/uPAR system's role in PTC invasion/metastasis and demonstrate the attractiveness of uPA and uPAR as molecular biomarkers and therapeutic targets.
A Polycation Scaffold Presenting Tunable “Click” Sites: Conjugation to Carbohydrate Ligands and Examination of Hepatocyte‐Targeted pDNA Delivery
Authors: Lee Chen‐Chang , Grandinetti Giovanna , McLendon Patrick M. , Reineke Theresa M.
Published: May 2010

A versatile polycation scaffold that can easily be modified with targeting ligands has been designed, synthesized, and characterized. A series of galactose‐containing polymers has been produced to demonstrate the ease of modification of this polynucleotide delivery vehicle motif via the click reaction and to study how various structural modifications affect recognition by ASGPr on hepatocytes. A small library of structures was created where DCS and alkyl spacer length between the targeting group and the polymer backbone was varied. The novel polymer scaffold described proves to be a valuable tool for understanding structure/activity relationships of complexes made with receptor‐targeted polymers.

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Accounting for Solvent Signal Offsets in the Analysis of Interferometric Sedimentation Velocity Data
Authors: Zhao Huaying , Brown Patrick H. , Balbo Andrea , Fernández‐Alonso María del Carmen , Polishchuck Natasha , Chaudhry Charu , Mayer Mark L. , Ghirlando Rodolfo , Schuck Peter
Published: May 2010

Sedimentation velocity (SV) analytical ultracentrifugation has re‐emerged as an important tool in the characterization of biological macromolecules and nanoparticles. The computational analysis of the evolution of the macromolecular concentration profile allows the characterization of many hydrodynamic and thermodynamic properties of the macromolecules and their interactions. The Rayleigh interference optical system is often the detection method of choice, for its usually superior data quality and the wide applicability of refractive index sensitive detection. However, the interference optical system is also sensitive to the redistribution of co‐solvent molecules, which are not of primary experimental interest. In principle, their contribution can be eliminated by an exact geometric and compositional match of the sample solution and the reference solution, achieving the complete optical subtraction of unwanted buffer signals. Unfortunately, in practice, this can often not be perfectly achieved for various reasons, leading to signal offsets arising from unmatched sedimentation of solvent components. If unrecognized, this can lead to significant misfit, accompanied by significant errors in the macromolecular sedimentation parameters. In the present work, we describe an approach of computationally accounting for signals from sedimenting buffer components through explicitly modeling their redistribution with Lamm equation solutions, implemented in the software SEDFIT. We demonstrate how this can restore the SV analysis to yield a high quality fit of the data and to provide correct macromolecular sedimentation parameters.

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Towards Semiconducting Graft Copolymers: Switching from ATRP to “Click” Approach
Authors: Bolognesi Alberto , Galeotti Francesco , Mróz Wojciech , Gancheva Valeria , Terlemezyan Levon
Published: May 2010

The synthesis of two polyconjugated graft copolymers based on a poly(fluorene‐phenylene) backbone and polystyrene side chains is described here. The two different approaches followed, ATRP growth of side chains from a preformed conjugated backbone and “click” connection of well‐defined polymeric chains to the backbone, led to different results in terms of solubility and material properties. While the ATRP method seems to be responsible of a partially cross‐linked and nonsoluble copolymer, the “click” approach provides a graft copolymer, which is completely soluble, showing atypical spectroscopic properties that are here elucidated.

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Highly Flexible Electronic and Optical Films Composed of Hydrophobic and Hydrophilic Multilayers
Authors: Kim Sungwoo , Lee Bokyoung , Kim Sanghyo , Bang Joona , Cho Jinhan
Published: May 2010

We introduce a novel and efficient strategy for producing free‐standing functional films via photo‐crosslinking and electrostatic layer‐by‐layer (LbL) assembly, which can allow the build‐up of hydrophilic multilayers onto hydrophobic surfaces. Hydrophobic multilayers were deposited on ionic substrates by a photo‐crosslinking LbL process using photo‐crosslinkable polymers. The photo‐crosslinked surface was converted to an anionic surface by excess UV light irradiation. This treatment allowed also the stable adhesion between metal electrode or cationic polyelectrolyte and hydrophobic multilayers. After dissolving the ionic substrates in water, the formed free‐standing films exhibited unique functionalities of inserted components within hydrophobic and/or hydrophilic multilayers.

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Poly[(vinylidene fluoride)‐co‐trifluoroethylene] Membranes Obtained by Isothermal Crystallization from Solution
Authors: Ferreira Armando , Silva Jaime , Sencadas Vitor , Ribelles José Luis Gómez , Lanceros‐Méndez S.
Published: May 2010

Electroactive macroporous poly[(vinylidene fluoride)‐co‐trifluoroethylene] membranes have been produced by solvent evaporation at room temperature, starting with a diluted solution of the copolymer in dimethylformamide. The pore architecture consists of interconnected spherical pores. This architecture is independent of the membrane thickness. The thickness of the membranes ranges from a few to several hundred µm, using spin coating and evaporation in static conditions, respectively. The pore structure is explained by a spinodal decomposition of the liquid/liquid phase separation and crystallization in the copolymer‐rich phase.

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Hollow Poly(3‐hydroxybutyrate) Fibers Produced by Melt Spinning
Authors: Hinüber Claudia , Häussler Liane , Vogel Roland , Brünig Harald , Werner Carsten
Published: May 2010

Native and nucleated PHB has been melt‐spun and the properties of the resulting fibers have been investigated. Biocompatible nucleating agents such as HAP and THY were compared to BN as a reference material. DSC was used to investigate the non‐isothermal crystallization kinetics as a function of processing temperature and cooling rate. It was found that particularly the choice of process temperature can ensure sufficient primary crystallization of native PHB: heating not higher than 10–15 K above the melting temperature induced a favorable crystallization behavior of native PHB. Thus, melt spinning at low process temperatures without additives was demonstrated to be the key to the formation of well‐defined hollow PHB fibers.

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Hydrolytic Depolymerization of PET in a Microwave Reactor
Authors: Siddiqui Mohammad Nahid , Achilias Dimitris S. , Redhwi Halim Hamid , Bikiaris Dimitris N. , Katsogiannis Konstantinos–Alexandros G. , Karayannidis George P.
Published: May 2010

Recycling of PET was examined using hydrolytic depolymerization in an alkaline solution under microwave irradiation. The reaction was carried out in a sealed microwave reactor in which the pressure and temperature were controlled and recorded. The main products were the monomers TPA and EG. The effect of reaction temperature, time, amount of PET and alkaline concentration on the degree of PET depolymerization and TPA recovery was investigated. Microwave irradiation was found to reduce the time needed to achieve a specific degradation of PET significantly, with almost complete depolymerization occurring in 30 min at 180 °C and only 46 W of microwave power. Using a phase transfer catalyst (TOMAB) resulted in the same amount of unreacted PET but at significantly lower depolymerization temperatures.

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Intracellular Protein Delivery Systems Formed by Noncovalent Bonding Interactions between Amphipathic Peptide Carriers and Protein Cargos
Authors: Lo Seong Loong , Wang Shu
Published: May 2010

Successful molecular therapy using protein‐based therapeutic agents for intracellular targets depends on the development of efficient and safe protein delivery systems that are able to overcome the problem of poor permeability of cell membrane to proteins. Here, we summarize recent studies elucidating how one particular class of peptide‐based carriers, amphipathic peptide, has been designed and utilized for intracellular protein delivery in a simple yet effective manner. The unique feature of these delivery systems lies in the noncovalent binding of amphipathic peptides to protein cargos, mainly through hydrophobic interactions. At least five different types of amphipathic peptides have been developed and demonstrated to be able to deliver various biologically active proteins into a variety of cell types without the use of chemical conjugation. In view of their efficiency and presumably low toxicity, we anticipate that amphipathic peptides will continue to be developed as powerful carriers for intracellular delivery of protein therapeutics.

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Ultrafast Responsive Poly‐ (N‐isopropylacrylamide) Gel Produced by Cryostructuring of Self‐crosslinkable Polymer Microgels
Authors: Kirsebom Harald , Mattiasson Bo , Galaev Igor Yu.
Published: May 2010

A macroporous material composed of closely aggregated particles was prepared by cryo‐structuration of N‐isopropylacrylamide‐co‐N‐hydroxymethylacrylamide (NIPA‐co‐HMAm) particle suspensions. The formed structure was maintained by the formation of covalent bonds through self‐crosslinking between the particles while the system was in a semi‐frozen state thus avoiding the need to freeze‐dry the sample. This resulted in macroporous structure composed of closely aggregated thermoresponsive particles which exhibit an ultrafast temperature response. The response rate can be attributed both to the macroporous structure as well as the fast responsive properties of the individual particles.

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Seeded Growth and Solvent‐Induced Fragmentation of Fiberlike Polyferrocenylsilane–Polyisoprene Block Copolymer Micelles
Authors: Qian Jieshu , Guerin Gerald , Cambridge Graeme , Manners Ian , Winnik Mitchell A.
Published: May 2010

Addition of a concentrated solution of PI1000–PFS50 dissolved in THF to a solution of PI1000–PFS50 seed micelles in decane led to the formation of uniform elongated fiberlike micelles with a narrow length distribution. When additional THF (>10 vol.‐%) was added to the micelles, the micelle length decreased and the contour‐length distribution broadened. This effect was shown to be inconsistent with a transition to an equilibrium, in which individual polymer molecules dissociated from and added to existing micelles. Rather, it appears that the polar solvent induced fragmentation of the fiberlike micelles.

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