bluuebunny/crossref_metadata_2025 huggingface dataset:
CD2AP and Cbl-3/Cbl-c Constitute a Critical Checkpoint in the Regulation of Ret Signal Transduction
Authors: Tsui Cynthia C. , Pierchala Brian A.
Published: August 2008

The glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs) are critical for nervous system development and maintenance. GFLs promote survival and growth via activation of the receptor tyrosine kinase (RTK) Ret. In sympathetic neurons, the duration of Ret signaling is governed by how rapidly Ret is degraded after its activation. In an effort to elucidate mechanisms that control the half-life of Ret, we have identified two novel Ret interactors, CD2-associated protein (CD2AP) and Cbl-3. CD2AP, an adaptor molecule involved in the internalization of ubiquitinated RTKs, is associated with Ret under basal, unstimulated conditions in neurons. After Ret activation by GDNF, CD2AP dissociates. Similarly, the E3-ligase Cbl-3 interacts with unphosphorylated Ret and dissociates from Ret after Ret activation. In contrast to their dissociation from autophosphorylated Ret, an interaction between CD2AP and Cbl-3 is induced by GDNF stimulation of sympathetic neurons, suggesting that CD2AP and Cbl-3 dissociate from Ret as a complex. In neurons, the overexpression of CD2AP enhances the degradation of Ret and inhibits GDNF-dependent survival, and gene silencing of CD2AP blocks Ret degradation and promotes GDNF-mediated survival. Surprisingly, Cbl-3 overexpression dramatically stabilizes activated Ret and enhances neuronal survival, even though Cbl-family E3 ligases normally function to trigger RTK downregulation. In combination with CD2AP, however, Cbl-3 promotes Ret degradation rapidly and almost completely blocks survival promotion by GDNF, suggesting that Cbl-3 acts as a switch that is triggered by CD2AP and oscillates between inhibition and promotion of Ret degradation. Consistent with the hypothesis, Cbl-3 silencing in neurons only inhibited Ret degradation and enhanced neuronal survival in combination with CD2AP silencing. CD2AP and Cbl-3, therefore, constitute a checkpoint that controls the extent of Ret downregulation and, thereby, the sensitivity of neurons to GFLs.
Deep Brain Stimulation of the Nucleus Accumbens Shell Attenuates Cocaine Priming-Induced Reinstatement of Drug Seeking in Rats: Figure 1.
Authors: Vassoler Fair M. , Schmidt Heath D. , Gerard Mary E. , Famous Katie R. , Ciraulo Domenic A. , Kornetsky Conan , Knapp Clifford M. , Pierce R. Christopher
Published: August 2008

Increasing evidence suggests that deep brain stimulation (DBS), which is currently being used as a therapy for neurological diseases, may be effective in the treatment of psychiatric disorders as well. Here, we examined the influence of DBS of the nucleus accumbens shell on cocaine priming-induced reinstatement of drug seeking, an animal model of relapse. Rats were allowed to self-administer cocaine (0.25 mg, i.v.) 2 h daily for 21 d and then cocaine-seeking behavior was extinguished by replacing cocaine with saline. During the reinstatement phase, DBS was administered bilaterally to the nucleus accumbens shell through bipolar stainless steel electrodes. Biphasic symmetrical pulses were delivered at a frequency of 160 Hz and a current intensity of 150 μA. DBS began immediately after a priming injection of cocaine (0, 5, 10, or 20 mg/kg, i.p.) and continued throughout each 2 h reinstatement session. Results indicated that only the higher doses of cocaine (10 and 20 mg/kg) produced robust and reliable reinstatement of cocaine seeking. DBS of the nucleus accumbens shell significantly attenuated the reinstatement of drug seeking precipitated by these higher cocaine doses. Additional experiments indicated that this DBS effect was both anatomically and reinforcer specific. Thus, DBS of the dorsal striatum had no influence on cocaine reinstatement and DBS of the accumbens shell did not affect the reinstatement of food seeking. Together, these results suggest that DBS of the nucleus accumbens shell may be a potential therapeutic option in the treatment of severe cocaine addiction.
Ovary and uterus transplantation
Authors: Gosden Roger G
Published: August 2008

Ovarian and uterine transplantation are procedures gaining more attention again because of potential applications in respectively fertility preservation for cancer and other patients and, more tentatively, women with uterine agenesis or hysterectomy. Cryopreservation of tissue slices, and possibly whole organs, is providing opportunities for banking ovaries for indefinite periods before transplanting them back to restore fertility. The natural plasticity of this organ facilitates grafting to different sites where they can be revascularized and rapidly restore the normal physiology of secretion and ovulation. Ischemic damage is a chief limitation because many follicles are lost, at least in avascular grafts, and functional longevity is reduced. Nevertheless, grafts of young ovarian tissue, even after cryopreservation, can be highly fertile in laboratory rodents and, in humans, autografts have functioned for up to 3 years before needing replacement. Transplantation by vascular anastomosis provides potentially longer function but it is technically much more demanding and riskier for the recipient. It is the only practicable method with the uterus, and has enabled successful pregnancies in several species, but not yet in humans. Contrary to claims made many years ago, neither organ is privileged immunologically, and allografts become rapidly rejected except in hosts whose immune system is deficient or suppressed pharmacologically. All in all, transplantation of these organs, especially the ovary, provides a broad platform of opportunities for research and new applications in reproductive medicine and conservation biology.
Reduction in Adverse Symptoms as Blood Pressure Becomes Controlled
Authors: Weber Cynthia A. , Leloux Megan R. , Carter Barry L. , Farris Karen B. , Xu Yinghui
Published: August 2008

Study Objectives. To evaluate trends in adverse symptoms as blood pressure becomes controlled, and to determine if these symptoms are influenced by social support and self‐efficacy.

Design. Secondary analysis from a randomized controlled study of physician‐pharmacist collaboration to improve blood pressure control.

Setting. Five university‐affiliated primary care clinics.

Patients. A total of 179 patients (aged 21–85 yrs) with uncontrolled primary hypertension who were taking no antihypertensive drugs or up to three antihypertensive drugs at baseline were randomized to the intervention group, in which pharmacists were involved in their care, or to the control group, who received usual care from their physicians. Of these patients, 160 completed the study: 92 were in the intervention group, and 68 were in the control group.

Intervention. In both groups, patient‐reported symptoms suggestive of adverse drug reactions (ADRs) were recorded at each study visit with use of a structured ADR questionnaire. Social support and self‐efficacy questionnaires were also administered at each study visit.

Measurements and Main Results. Patients' ADR scores decreased significantly from baseline to the end of the study in both the control (from a mean of 26.5 to 18.4) and intervention (from 29.9 to 22.7) groups (p<0.0001 for both comparisons), although no significant difference was noted between groups. The mean ± SD number of antihypertensive drugs/patient increased in both the intervention (from 1.5 ± 1.0 to 2.4 ± 0.9 drugs) and control (from 1.4 ± 1.0 to 1.9 ± 1.0 drugs) groups; however, the difference between groups was significant only at the end of the study. Additional analyses were performed on self‐efficacy and social support to determine a potential reason for the reduction in ADR scores despite an increase in drug use. Improvements in self‐efficacy and social support scores were significantly and independently associated with improvement in ADR score (p<0.05).

Conclusions. In both groups, ADR scores improved despite an increase in antihypertensive drug use. Improvements in social support and, to a lesser extent, self‐efficacy were associated with improvements in ADR scores. Patients should not expect an increase in distressful symptoms as their blood pressure becomes controlled with antihypertensive drugs, especially when adequate social support is available.
Contrast Medium‐Induced Nephropathy: Strategies for Prevention
Authors: Massicotte Anne
Published: August 2008

Contrast medium‐induced nephropathy (CIN) is the third leading cause of acute renal failure in hospitalized patients. The exact mechanism by which contrast media induce renal failure is complex and not completely understood. Alteration in renal hemodynamics and direct toxicity to tubular cells have been proposed. The most important risk factor for development of CIN is preexisting renal insufficiency. Identification of patients with risk factors for development of CIN is essential, as measures for prevention of CIN can be instituted. Administration of fluids such as sodium chloride has been the traditional cornerstone of preventive therapy. Alkalization of tubular fluid with intravenous sodium bicarbonate has dramatically reduced the frequency of CIN in patients with baseline impaired renal function. Based on available evidence, use of sodium bicarbonate constitutes the most reliable and effective option. Prevention of CIN has also been achieved with periprocedural use of N‐acetylcysteine, but not as consistently as with sodium bicarbonate. Although many studies evaluated different N‐acetylcysteine dosages and routes of administration, the optimal regimen has yet to be determined. Combinations of these preventive therapies are just emerging and require further research.
Development of Unilateral Cervical and Supraclavicular Lymphadenopathy After Human Papilloma Virus Vaccination
Authors: Studdiford James , Lamb Kathleen , Horvath Kedron , Altshuler Marc , Stonehouse Amber
Published: August 2008

A 26‐year‐old woman developed significant unilateral anterior cervical and supraclavicular lymphadenopathy 3 days after receiving her first dose (of a total of three doses) of human papilloma virus (HPV) vaccine. She had no history of lymphadenopathy after other previous immunizations, and had received no vaccines other than HPV at that time. The left‐sided lymphadenopathy developed after she was vaccinated in the left deltoid muscle. The spatial and temporal relationships between the appearance of the lymphadenopathy and receipt of the vaccine in the absence of other causal agents strongly suggest that the HPV vaccine was the causal agent. Use of the Naranjo adverse drug reaction probability scale indicated that the HPV vaccine was a probable (score of 6) cause of the patient's adverse reaction. The patient received her second dose of the HPV vaccine 2 months later without further lymphadenopathy. To prevent unnecessary lymph node biopsies and patient concern, clinicians should be aware that lymphadenopathy may occur after HPV vaccination.
Signal regulatory protein α1 is involved in the inhibitory effect of glucocorticoid receptor on the proliferation of murine macrophage RAW264.7 cell and mouse peritoneal macrophage
Authors: Wang Xiaohui , Li Yidong , Zhu Xiaoyan , Wang Yan , Diao Fei , Lu Jian
Published: August 2008

Glucocorticoid (GC) effectively suppresses immune and inflammatory responses and inhibits the growth of several types of cells, but the role of GC and its receptor on macrophage proliferation is unclear. In our previous work, we found RAW-GR(−) cells (murine macrophage RAW264.7 cells stably transfected with GR-siRNA expression vector by RNA interference) grew faster by about twofold. In this study, we further explored the role and mechanisms of GC/GR on the proliferation of macrophage. We found that the growth of RAW264.7 cells was inhibited by dexamethasone (Dex) in a concentration-dependent manner. The mRNA and protein levels of signal regulatory protein α1 (SIRPA) were induced by GC/GR in RAW264.7 cells and SIRPA expression was decreased remarkably in RAW-GR(−) cells. Overexpression of SIRPA negatively regulated the proliferation of RAW-GR(−) cells, and inhibition of SIRPA expression by a small from RNA interference attenuated Dex-induced proliferation inhibition in RAW264.7 cells. The proliferation inhibition of GC/GR was also found in mouse peritoneal macrophage, which was associated with the increase in SIRPA induced by GC/GR as well. In addition, elevation of the expression of CDK2, cyclinD1, and cyclinB1, but not phosphorylated ERK1/2 and p38, was found in RAW-GR(−) cells. In conclusion, we provided the novel evidences that GC/GR inhibited the growth of RAW264.7 cells and mouse peritoneal macrophage, and the antiproliferative effect of GC/GR on these cells was at least in part a result from GC/GR-induced SIRPA expression. Up-regulation of CDK2, cyclinD1, and cyclinB1 was also related to the increased proliferation of RAW-GR(−) cells.
Two cytochrome P450 aromatase genes in the hermaphrodite ricefield eel Monopterus albus: mRNA expression during ovarian development and sex change
Authors: Zhang Yang , Zhang Weimin , Yang Huiyi , Zhou Wenliang , Hu Chaoqun , Zhang Lihong
Published: August 2008

Previously, the ricefield eel (Monopterus albus) was speculated to have only one cytochrome p450 aromatase gene. In this study, however, the cDNAs encoding two distinct cytochrome p450 aromatases, cyp19a1a and cyp19a1b, were isolated. The genomic organizations of both cyp19 genes were conserved when compared with other teleosts. Northern blot detected an abundant expression of cyp19a1a in the ovary, and cyp19a1b in the hypothalamus. RT-PCR coupled with Southern blot showed that cyp19a1a was expressed predominantly in the gonads of both sexes, with higher levels in the ovary than testis, while cyp19a1b was expressed in all the tissues examined in the male, but only in the brain and pituitary in the female. The levels of cyp19a1a mRNA in the ovary were increased significantly during vitellogenesis, but decreased significantly at mature stage. The levels of cyp19a1b mRNA in the brain and pituitary did not vary significantly during vitellogenesis. As ovarian development shifted from vitellogenesis to maturation, the levels of cyp19a1b mRNA was decreased significantly in the brain, but increased significantly in the pituitary. During natural sex change from female to male, the levels of cyp19a1a mRNA in the gonad were significantly decreased. The levels of cyp19a1b mRNA in the hypothalamus were significantly increased at the early intersexual phase, whereas the expression levels in the pituitary were significantly decreased at the intersexual phases. Taken together, these results showed a novel sexual dimorphism of cyp19a1b mRNA tissue distribution, and both CYP19 genes were associated with the ovarian development and natural sex change of the ricefield eel.
Development of a Heat Transfer Coefficient Model via Experimental Validation
Authors: Al-Hemiri Adel A. , Ahmedzeki Nada Sadoon
Published: August 2008

Knowledge of the heat transfer coefficient is an essential prerequisite for any industrial gas/liquid bubble column reactor design. In this paper, experiments were carried out in a laboratory scale bubble column using airwater and 10wt% glycerinair solution systems. Experimental values of the heat transfer coefficient were compared with some of the previous published correlations and were also compared with the model predicted by ANN in our previous work (Ahmedzeki, 2007). The ANN model was found to be better than all previous published correlations. %AARE was 8.2 and %standard deviation was 7.85. A mechanistic model was also developed to analyze the system. The resulting correlation was a %AARE of 17.5 and %standard deviation of 15. Both the above models and the experimental results compared well with the previous published correlations.
Population-Specific Risk of Type 2 Diabetes Conferred by HNF4A P2 Promoter Variants
Authors: Barroso Inês , Luan Jian’an , Wheeler Eleanor , Whittaker Pamela , Wasson Jon , Zeggini Eleftheria , Weedon Michael N. , Hunt Sarah , Venkatesh Ranganath , Frayling Timothy M. , Delgado Marcos , Neuman Rosalind J. , Zhao Jinghua , Sherva Richard , Glaser Benjamin , Walker Mark , Hitman Graham , McCarthy Mark I. , Hattersley Andrew T. , Permutt M. Alan , Wareham Nicholas J. , Deloukas Panagiotis
Published: August 2008

OBJECTIVE—Single nucleotide polymorphisms (SNPs) in the P2 promoter region of HNF4A were originally shown to be associated with predisposition for type 2 diabetes in Finnish, Ashkenazi, and, more recently, Scandinavian populations, but they generated conflicting results in additional populations. We aimed to investigate whether data from a large-scale mapping approach would replicate this association in novel Ashkenazi samples and in U.K. populations and whether these data would allow us to refine the association signal.

RESEARCH DESIGN AND METHODS—Using a dense linkage disequilibrium map of 20q, we selected SNPs from a 10-Mb interval centered on HNF4A. In a staged approach, we first typed 4,608 SNPs in case-control populations from four U.K. populations and an Ashkenazi population (n = 2,516). In phase 2, a subset of 763 SNPs was genotyped in 2,513 additional samples from the same populations.

RESULTS—Combined analysis of both phases demonstrated association between HNF4A P2 SNPs (rs1884613 and rs2144908) and type 2 diabetes in the Ashkenazim (n = 991; P < 1.6 × 10−6). Importantly, these associations are significant in a subset of Ashkenazi samples (n = 531) not previously tested for association with P2 SNPs (odds ratio [OR] ∼1.7; P < 0.002), thus providing replication within the Ashkenazim. In the U.K. populations, this association was not significant (n = 4,022; P > 0.5), and the estimate for the OR was much smaller (OR 1.04; [95%CI 0.91–1.19]).

CONCLUSIONS—These data indicate that the risk conferred by HNF4A P2 is significantly different between U.K. and Ashkenazi populations (P < 0.00007), suggesting that the underlying causal variant remains unidentified. Interactions with other genetic or environmental factors may also contribute to this difference in risk between populations.
Oscillation of fourth order nonlinear neutral difference equations-II
Authors: Tripathy A.
Published: August 2008

Oscillatory and asymptotic behaviour of solutions of a class of fourth order nonlinear neutral difference equations of the form $$
\Delta ^2 (r(n)\Delta ^2 (y(n) + p(n)y(n - m))) + q(n)G(y(n - k)) = 0
$$ and $$
(E) \Delta ^2 (r(n)\Delta ^2 (y(n) + p(n)y(n - m))) + q(n)G(y(n - k)) = f(n)
$$ are studied under the assumption $$
\sum\limits_{n = 0}^\infty {\tfrac{n}
{{r(n)}}}
$$ < ∞, for different ranges of p(n). Sufficient conditions are obtained for the existence of positive bounded solutions of (E).
From the Cradle to the Grave: Politics, Families and Inheritance Law
Authors: Reid Dot
Published: August 2008

Property is political. The extent to which a society restricts or encourages freedom of ownership and the accumulation of wealth reflects the values of that society, whether they spring from a Marxist ideology at one end of the political spectrum or from a commitment to liberal individualism and the operation of a free market at the other.1 Property ownership is the foundation stone of a capitalist economy2 and the spread of home ownership a core philosophy of all modern political parties.

The extent to which the law should interfere with individual choice in relation to family behaviour is an issue which elicits a range of views across the political spectrum, closely related to preference for “big” or “small” government and sympathy (or lack of it) for a degree of social engineering. Modern British governments tread warily in this territory, reluctant to create controversy or to risk accusations of being a “nanny” state. But none has completely eschewed policy initiatives which affect the institution of the family.
Reading Dual Meanings of Power on Young Women's Bodies: The Representation of Cosmetic Surgery in Japanese Manga
Authors: HANABUSA MIYUKI
Published: August 2008

Contemporary theoretical trends have brought the body into the foreground as a social/cultural construction based on various power relations. Within broader discussions of individual concerns about physical appearance, the alteration of the body by means of cosmetic surgery has become a highly topical issue. Such procedures have now become widespread and are beginning to impact even on youth across developed countries; representations of cosmetic surgery are now also beginning to feature in a range of media, including manga. Although a relatively new medium, manga treats a wide variety of themes and reaches a large audience including young people; the appearance of cosmetic surgery as one of its concerns reflects youth culture's interest in this new fashion. Discussions of media representations of cosmetic surgery tend to centre on gender (as women/girls predominate in terms of the number of patients), and on race. As often noted, Japan (along with other Asian countries) is, with its particular historical and social background, greatly influenced by Western standards of beauty. This article will consider, from the angles listed above, four manga texts that deal with cosmetic surgery. In pointing out not only the reproduction of the power relations but also the potential for subverting those relations, it will read these dual powers on the bodies of the young characters, depicted as subjects of cosmetic surgical procedures.
A ‘middle road’ approach to bridging the basic–applied divide in eyewitness identification research
Authors: Lane Sean M. , Meissner Christian A.
Published: August 2008

Over a century of laboratory research has explored the mechanisms of memory using a variety of paradigms and stimuli. In addition, many researchers have taken up Neisser's challenge to examine memory under real‐world conditions, most prominently including the eyewitness identification problem. Unfortunately, these ‘high road’ and ‘low road’ perspectives rarely communicate with one another, with the eyewitness field largely adopting an approach that focusses on methodological adherence to conditions that mimic real‐world situations. In the current paper we advocate for a ‘middle road’ approach that includes a focus on theory development, an emphasis on the interaction between field and laboratory research and the implementation of convergent approaches to investigating eyewitness identification. We argue that the field would be invigorated by such an approach, with benefits accruing to our understanding of eyewitness identification and to the development of procedures that will ultimately improve eyewitness accuracy. Copyright © 2008 John Wiley & Sons, Ltd.
Complete dissolution and hydrolysis of wood in hot water
Authors: Fang Zhen , Fang Chun
Published: August 2008

When willow and water were heated rapidly (7–16°C/s) to high temperatures and high pressures, most of willow (90 vol %) dissolved in water at 341°C in 2.5 s without complete dissolution. Adding 0.8 wt % Na2CO3, complete dissolution of willow (concentration up to 35 vol %) was observed at 329–367°C and water densities of 322–787 kg/m3 (14–106 MPa) in 1.5 s. By cooling the solublized willow immediately, micron particles were obtained via precipitation. If heated further to 400°C, willow was completely hydrolyzed to sugars/sugar oligomers in 14.6 s at homogeneous conditions. A flow reactor was proposed to completely solubilize willow for the production of micron particles, sugars, bio‐fuels and chemicals continuously. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Synthesis, structure characterization and catalytic activity of lanthanide complexes containing an ansa carbonous‐bridged cyclopentadienyl—thienyl ligand
Authors: Xie Xiaomin , Huang Jiling
Published: August 2008

A kind of new lanthanocene complex with an ansa carbonous‐bridged cyclopentadienyl/aromatic heterocycle ligand was prepared and characterized. Based on the data of elemental analyses, MS and IR, they were presumed to be solvent‐free complexes (cyclo‐C4H3SCMe2C5H4)2LnCl [Ln = Er (1), Dd (2), Y (3), Sm (4)]. These complexes were effective for the polymerization of methyl methacrylate in the presence of co‐catalyst. When AlEt3 and NaH (nanometric) were used as different co‐catalysts, the lanthanocene complexes 1–4 showed different catalytic behavior. These differences resulted from the formation of different active species. The catalyst system (cyclo‐C4H3SCMe2C5H4)2LnCl/NaH (nanometric) showed high catalytic activity (yield ≥ 95% and Mη > 105) in a short time at the ambient temperature. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of promoters and secondary fluidizing medium on mixing: statistical and ANN approaches
Authors: Mohanty Y. K. , Mohanty B. P. , Roy G. K. , Biswal K. C.
Published: August 2008

Factorial design (statistical approach) and artificial neural network (ANN) models have been developed for the prediction of mixing the index with four system parameters, such as static bed heights, average particle densities, average particle sizes and gas velocities, under four different experimental conditions, viz., only primary air, simultaneous primary and secondary air, disc promoter and rod promoter. The values of the mixing index obtained through the developed models are found to agree well with their experimental counterparts. It has also been found from these investigations that under simultaneous primary and secondary air supply conditions the best mixing performance is achieved, i.e. IM ≈ 1.0, as compared to rod promoter, disc promoter, and only primary air supply. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.
Springs in time: fish fauna and habitat changes in springs over a 20‐year interval
Authors: Bergey Elizabeth A. , Matthews William J. , Fry Jennifer E.
Published: August 2008

Despite the range of threats to springs and the number of spring‐endemic species, studies of temporal changes in the fauna of springs have rarely been reported. Changes in the fish of 22 Oklahoma (USA) springs were compared among surveys in 1981, 1982, and 2001.

Twenty‐year assemblage differences were correlated with physical alteration of specific springs and stocking of native fish, which was made possible by past habitat changes that produced pools. Physical alteration of springs is a major ongoing threat to Oklahoma springs.

Variation in spring fish assemblages among the three surveys was apparently affected by fish movement in and out of springs, and the greater rain‐induced connectivity between springs and streams during one year.

Although flow reduction is a commonly cited threat to springs, there was little evidence of flow reduction impacts in this study because Oklahoma springs may have been affected prior to 1981 and high‐flow springs, which most often contain fish, were in areas with low groundwater water use.

Copyright © 2008 John Wiley & Sons, Ltd.
Gas‐Liquid Mass Transfer Approach applied to the Modeling of Flotation in a Bubble Column
Authors: Chahed J. , M'Rabet K.
Published: August 2008

A kinetic model developed to describe flotation in a bubble column is presented. This model, developed on the basis of the theory of mass transfer in gas‐liquid flows, makes explicit in its formulation the effect of the superficial saturation of bubbles on the kinetics of flotation. The model is applied to the simulation of flotation column experiments for which the classical first‐order models, commonly used in flotation modeling, are insufficient to represent the flotation kinetics. The results of the simulations obtained under different hypotheses of simplification and compared to experimental data show that the model succeeds in representing the flotation kinetics in these cases.
Effect of Operating Parameters on the Condensation of Ammonium Sulfate by Electrodialysis
Authors: Yang H. , Zhang X.‐S. , Yuan W.‐K.
Published: August 2008

The separation of ammonium sulfate from dilute solution by electrodialysis was investigated. From the results obtained, it is suggested that it is feasible to separate ammonium sulfate from aqueous solution by electrodialysis. The removal performance of ammonium sulfate obtained was very satisfactory. The optimal cation and anion membranes were found. The removal efficiencies were influenced by voltage, initial concentration, flow rate and temperature. High voltage and high temperature are beneficial to this separation process, but high fluid flow rate and concentrated initial concentration prolong the operation time required to achieve the target value. It was found that the optimal outlet concentration is 1 g/L, since the operation time is prolonged almost two‐fold if the outlet concentration is decreased from 1 g/L to 0.5 g/L.
Heterogeneously Catalyzed Epimerization of Menthol Stereoisomers – An Instructive Example to Account for Diffusion Limitations in Complex Reaction Networks
Authors: Etzold B. , Jess A.
Published: August 2008

The heterogeneously catalyzed epimerization of menthol stereoisomers is an important step in the synthesis of (–)‐menthol by the Haarmann and Reimer process. For an accurate design of a technical reactor, the intrinsic kinetics as well as pore diffusion limitations have to be taken into account. The epimerization consists of a complex reaction network and so a simple approach using effectiveness factors based on Thiele moduli is not possible. In this work, a method is presented to simultaneously calculate the change in concentrations in the bulk phase as well as within the porous particles with time (fixed bed reactor) or local position (batch reactor). A commercially available numerical software was used to solve the differential equations.
Spectroscopic Investigation of the Interaction of BSA with Cationic Surfactants
Authors: Madaeni S. S. , Rostami E.
Published: August 2008

The interactions between dodecyltrimethylammonium bromide (DTAB), tetradecyltrimethylammonium bromide (TTAB), cetyltrimethylammonium bromide (CTAB), and hexadecylpyridinium chloride (HDPC) with bovine serum albumin (BSA) in an aqueous solution (pH = 7.0, 0.001 M HEPES buffer) were studied by fluorescence and circular dichroism (CD) measurements. These categories of surfactants were used to elucidate the effect of hydrophilic group and length of hydrophobic chain surfactant on the mechanism of binding to BSA. The result revealed that for all surfactants, at low concentrations, the Stern‐Volmer plots have an upward curvature and in high concentrations, the quenching efficiency was decreased with increase in surfactant concentration. The activation energy of the interaction between cationic surfactants and BSA was measured. The results of CD show that the conformation of BSA has been changed in the presence of cationic surfactants.
Experimental Study on Bubble Rising and Descending Velocity Distribution in a Slurry Bubble Column Reactor
Authors: Zhang Li‐j. , Li T. , Ying W.‐y. , Fang D.‐y.
Published: August 2008

To determine bubble rising and descending velocity simultaneously, a BVW‐2 four‐channel conductivity probe bubble parameters apparatus and its analysis are used in gas‐liquid and gas‐liquid‐solid bubble columns. The column is 100 mm in internal diameter and 1500 mm in height. The solid particles used are glass beads with an average diameter of 17.82 μm, representing typical particle size for catalytic slurry reactors. The effects of superficial gas velocity (1.0 cm/s ≤ Ug ≤ 6.4 cm/s), solid holdup (0 % ≤ ϵs ≤ 30 %), and radial location (r/R = 0, 0.4, and 0.7) on bubble velocity distributions are determined. It is found that increasing Ug can increase the velocity of bubbles but do not exert much influence on bubble velocity distribution. Solid holdup mainly affects the distribution of bubble velocity while the radial direction affects bubble velocity distribution only slightly. The ratio of descending bubbles to rising bubbles increases from the bubble column center to the wall. It can be proved experimentally that large bubbles do not always rise faster than small bubbles at higher Ug (for example 6.4 cm/s).
Recent Synthetic Applications of Manganese in Organic Synthesis
Authors: Concellón José M. , Rodríguez‐Solla Humberto , del Amo Vicente
Published: August 2008

While the organometallic compounds derived from many metals have found a broad application in organic synthesis, the use of organomanganese compounds has only recently been developed due to the passivity exhibited by commercial Mn in the direct metalation of organic compounds. In this Concept article, we highlight the potential of manganese and its organometallic compounds in organic synthesis by illustration of the studies previously reported by others and our laboratory in this field. Based on the transformations reported herein, organomanganese compounds could become important tools in the future of the organic synthesis, due to their high selectivity.
Structure–Reactivity Relationship in Alkane Metathesis Using Well‐Defined Silica‐Supported Alkene Metathesis Catalyst Precursors
Authors: Blanc Frédéric , Thivolle‐Cazat Jean , Basset Jean‐Marie , Copéret Christophe
Published: August 2008

Alkane metathesis can be performed by using well‐defined silica‐supported alkene metathesis catalyst precursors as long as the coordination sphere of the metal centre contains both alkyl and alkylidene groups, such as in [(SiO)Mo(NAr)(CHtBu)(CH2tBu)]. This system transforms mainly linear alkanes, from propane to hexane, into their lower and higher homologues. Mechanistic studies clearly show that alkene metathesis is a key step of this reaction and also suggest that this system is a single‐site single‐component system, namely, alkenes are formed and transformed on one site, which is in contrast to that observed with a mixture of catalysts.
Enantioselective addition of phenylacetylene to N‐aryl arylimines catalyzed by Cu(II)‐pyridine containing N‐tosylatedaminoimine ligand complex
Authors: Liu Bao , Zhong Yao , Li Xingshu
Published: August 2008

Chiral tridentate N‐tosylated pyridine‐containing ligands were prepared and used in the Cu(II)‐catalyzed enantioselective addition of phenylacetylene to N‐aryl arylimines. Moderate to high enantioselectivities (up to 95% ee) were obtained in very mild reaction conditions. Chirality, 2008. © 2009 Wiley‐Liss, Inc.
Synthesis of enantiopure 2‐(aminoalkyl)phenol derivatives and their application as catalysts in stereoselective reactions
Authors: Cimarelli Cristina , Palmieri Gianni
Published: August 2008

Enantiopure 2‐(aminoalkyl)phenol derivatives are an interesting class of compounds widely used in homogeneous ligand accelerated catalysis. A series of practical and convenient methods available for their preparation are revised, together with the methodologies for the determination of their configuration. The uses of these compounds in metal catalysed asymmetric reactions in the addition of dialkyl zinc reagents to aldehydes and in the reduction of ketones with borane are described. Moreover 2‐(aminoalkyl)phenol derivatives have found use also as chiral shift reagents for carboxylic acids. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Computer‐Aided Design and Synthesis of Nonpeptidic Plasmepsin II and IV Inhibitors
Authors: Luksch Torsten , Chan Nan‐Si , Brass Sascha , Sotriffer Christoph A. , Klebe Gerhard , Diederich Wibke E.
Published: August 2008

Plasmepsins (Plm) II (EC number: 3.4.23.39) and IV (EC number: 3.4.23.B14) are aspartic proteases present in the food vacuole of the malaria parasite Plasmodium falciparum and are involved in host hemoglobin degradation. Based on our established efficient synthetic sequence, a series of inhibitors for Plm II and IV has been synthesized bearing a 2,3,4,7‐tetrahydro‐1H‐azepine scaffold as the core structural element. During the computational design cycle, thorough investigations were carried out in order to find a reasonable theoretical binding mode for Plm II and IV. The conformation of Plm II in the crystal structure (PDB code: 1LF2) provides a good starting geometry for our virtual screening approach. In contrast, the only available co‐crystal structure for Plm IV of P. falciparum (PDB code: 1LS5) appears inappropriate for inhibitor design. Therefore, a homology model was constructed based on the Plm II 1LF2 structure. A combinatorial docking run using FlexXc suggested compounds which, after synthesis, turned out to exhibit affinities in the sub‐micromolar range. The observed structure–activity relationships of the synthesized compounds confirm the assumed binding mode for Plm II and IV. The best‐binding inhibitors designed for Plm II and IV are devoid of any inhibitory potency against human cathepsin D (EC number: 3.4.23.5).
Expression of kin of irregular chiasm‐like 3/mKirre in proprioceptive neurons of the dorsal root ganglia and its interaction with nephrin in muscle spindles
Authors: Komori Tadasuke , Gyobu Hiroaki , Ueno Hiroo , Kitamura Toshio , Senba Emiko , Morikawa Yoshihiro
Published: August 2008

Kin of irregular chiasm‐like 3 (Kirrel3), a mammalian homolog of the kirre gene of Drosophila melanogaster, belongs to the immunoglobulin superfamily. Previously, we have reported that Kirrel3 is expressed in the developing and adult central nervous system. In the present study we investigated the expression of Kirrel3 in the mouse dorsal root ganglia (DRG) and their projection targets. In the adult DRGs, Kirrel3 mRNA was detected in 21.5 ± 2.3% of total DRG neurons and the expression was mainly prevalent in the medium‐ and large‐sized neurons. In addition, Kirrel3 mRNA predominantly colocalized with tyrosine kinase receptor (Trk) C‐immunoreactivity. In the developing DRGs, Kirrel3 mRNA was first detected in a few cells at embryonic day (E) 11.5, gradually increased, and reached the adult level at E17.5. During the development, Kirrel3 was expressed in most TrkC‐positive DRG neurons. The expression of Kirrel3 was observed in TrkC‐positive nerve fibers around neurotrophin 3 (NT3)‐positive intrafusal muscle fibers of muscle spindles at E17.5. However, Kirrel3 was not expressed in TrkC‐positive nerve fibers projecting to the spinal cord throughout development. Furthermore, nephrin was expressed in the NT3‐positive intrafusal muscle fibers and was in close apposition with Kirrel3‐immunoreactivity. Coimmunoprecipitation assay revealed that nephrin interacted with Kirrel3 in the developing muscles. These results suggest that Kirrel3 might play a role in the axonal pathfinding, cell recognition, and synapse formation of DRG neurons on appropriate target cells, including the targeting of proprioceptive neurons on muscle spindles through the interaction with nephrin. J. Comp. Neurol. 511:92–108, 2008. © 2008 Wiley‐Liss, Inc.
Efficient Photoconversion Distorts the Fluorescence Lifetime of GFP in Confocal Microscopy: A Model Kinetic Study on Mutant Thr203Val
Authors: Jung Gregor , Werner Michael , Schneider Marc
Published: August 2008

Phototransformations of autofluorescent proteins are applied in high‐resolution microscopy and in studying cellular transport, but they are detrimental when accidentally occurring in blinking or photobleaching (BL). Here, we investigate the kinetics of phototransformations of a photoactivatable green fluorescent protein (GFP) in confocal microscopy. Photoconversion (PC) is achieved by excitation of the barely present anionic chromophore state Req− in the GFP mutant Thr203Val. Besides the shift of the equilibrium between the neutral chromophore state RH and Req−, the photoconverted anionic chromophore RPC− exhibits a reduced fluorescence lifetime τfl=2.2 ns. In fluorescence lifetime imaging microscopy, τfl is found to depend, however, on the excitation conditions and history. The underlying photochemistry is described by the kinetic scheme of consecutive reactions, Req−→RPC−→Pdark, in which the anionic chromophore species and the dark protein Pdark are coupled by PC and BL. Time‐correlated single‐photon‐counting detection in a confocal geometry of freely diffusing species is used to compute the quantum yields for PC and BL, ΦPC and ΦBL. The assessed values are ΦPC=5.5×10−4 and ΦBL>1×10−5. Based on these values, PC provokes misinterpretation in fluorescence resonance energy transfer experiments and is responsible for spectroscopic peculiarities in single‐molecule detection.
MIFlowCyt: The minimum information about a flow cytometry experiment
Authors: Lee Jamie A. , Spidlen Josef , Boyce Keith , Cai Jennifer , Crosbie Nicholas , Dalphin Mark , Furlong Jeff , Gasparetto Maura , Goldberg Michael , Goralczyk Elizabeth M. , Hyun Bill , Jansen Kirstin , Kollmann Tobias , Kong Megan , Leif Robert , McWeeney Shannon , Moloshok Thomas D. , Moore Wayne , Nolan Garry , Nolan John , Nikolich‐Zugich Janko , Parrish David , Purcell Barclay , Qian Yu , Selvaraj Biruntha , Smith Clayton , Tchuvatkina Olga , Wertheimer Anne , Wilkinson Peter , Wilson Christopher , Wood James , Zigon Robert , Scheuermann Richard H. , Brinkman Ryan R.
Published: August 2008

A fundamental tenet of scientific research is that published results are open to independent validation and refutation. Minimum data standards aid data providers, users, and publishers by providing a specification of what is required to unambiguously interpret experimental findings. Here, we present the Minimum Information about a Flow Cytometry Experiment (MIFlowCyt) standard, stating the minimum information required to report flow cytometry (FCM) experiments. We brought together a cross‐disciplinary international collaborative group of bioinformaticians, computational statisticians, software developers, instrument manufacturers, and clinical and basic research scientists to develop the standard. The standard was subsequently vetted by the International Society for Advancement of Cytometry (ISAC) Data Standards Task Force, Standards Committee, membership, and Council. The MIFlowCyt standard includes recommendations about descriptions of the specimens and reagents included in the FCM experiment, the configuration of the instrument used to perform the assays, and the data processing approaches used to interpret the primary output data. MIFlowCyt has been adopted as a standard by ISAC, representing the FCM scientific community including scientists as well as software and hardware manufacturers. Adoptionof MIFlowCyt by the scientific and publishing communities will facilitate third‐party understanding and reuse of FCM data. © 2008 International Society for Advancement of Cytometry
Inhibition of cell adhesion by xARVCF indicates a regulatory function at the plasma membrane
Authors: Reintsch Wolfgang E. , Mandato Craig A. , McCrea Pierre D. , Fagotto François
Published: August 2008

The cytoplasmic tail of cadherins is thought to regulate the strength and dynamics of cell–cell adhesion. Part of its regulatory activity has been attributed to a membrane‐proximal region, the juxtamembrane domain (JMD), and its interaction with members of the p120 catenin subfamily. We show that titration of xARVCF, a member of this family, to the plasma membrane disrupts adhesion in the early embryo. Adhesion can be restored by coexpression of constitutively active Rac, suggesting that intracellular signaling is the primary cause in the loss of adhesion phenotype. Our observations suggest that the recruitment of p120 type catenins to the plasma membrane by the cadherin cytoplasmic tail may create protein complexes, which actively modulate the adhesion “status” of embryonic cells. Developmental Dynamics 237:2328–2341, 2008. © 2008 Wiley‐Liss, Inc.
A critical evaluation of specific aspects of joint development
Authors: Pitsillides A.A. , Ashhurst Doreen E.
Published: August 2008

Synovial joint formation has been divided into two phases; the formation of the anlagen of the opposing bones and the interzone and the later formation of the joint cavity. Here we review current theories on the mechanism by which these events are achieved in the joints of the developing limb. Developmental Dynamics 237:2284–2294, 2008. © 2008 Wiley‐Liss, Inc.
Iris as a recipient tissue for pigment cells: Organized in vivo differentiation of melanocytes and pigmented epithelium derived from embryonic stem cells in vitro
Authors: Aoki Hitomi , Hara Akira , Motohashi Tsutomu , Chem Huayue , Kunisada Takahiro
Published: August 2008

Regenerative transplantation of embryonic stem (ES) cell‐derived melanocytes into adult tissues, especially skin that includes hair follicles or the hair follicle itself, generally not possible, whereas that of ES cell‐derived pigmented epithelium was reported previously. We investigated the in vivo differentiation of these two pigment cell types derived from ES cells after their transfer into the iris. Melanocytes derived from ES cells efficiently integrated into the iris and expanded to fill the stromal layer of the iris, like those prepared from neonatal skin. Transplanted pigmented epithelium from either ES cells or the neonatal eye was also found to be integrated into the iris. Both types of these regenerated pigment cells showed the correct morphology. Regenerated pigment epithelium expressed its functional marker. Functional blocking of signals required for melanocyte development abolished the differentiation of transplanted melanocytes. These results indicate successful in vivo regenerative transfer of pigment cells induced from ES cells in vitro. Developmental Dynamics 237:2394–2404, 2008. © 2008 Wiley‐Liss, Inc.
Fungiform papilla pattern: EGF regulates inter‐papilla lingual epithelium and decreases papilla number by means of PI3K/Akt, MEK/ERK, and p38 MAPK signaling
Authors: Liu Hong‐Xiang , Henson Bradley S. , Zhou Yanqiu , D'Silva Nisha J. , Mistretta Charlotte M.
Published: August 2008

Fungiform papillae are epithelial taste organs that form on the tongue, requiring differentiation of papillae and inter‐papilla epithelium. We tested roles of epidermal growth factor (EGF) and the receptor EGFR in papilla development. Developmentally, EGF was localized within and between papillae whereas EGFR was progressively restricted to inter‐papilla epithelium. In tongue cultures, EGF decreased papillae and increased cell proliferation in inter‐papilla epithelium in a concentration‐dependent manner, whereas EGFR inhibitor increased and fused papillae. EGF preincubation could over‐ride disruption of Shh signaling that ordinarily would effect a doubling of fungiform papillae. With EGF‐induced activation of EGFR, we demonstrated phosphorylation in PI3K/Akt, MEK/ERK, and p38 MAPK pathways; with pathway inhibitors (LY294002, U0126, SB203580) the EGF‐mediated decrease in papillae was reversed, and synergistic actions were shown. Thus, EGF/EGFR signaling by means of PI3K/Akt, MEK/ERK, and p38 MAPK contributes to epithelial cell proliferation between papillae; this biases against papilla differentiation and reduces numbers of papillae. Developmental Dynamics 237:2378–2393, 2008. © 2008 Wiley‐Liss, Inc.
Kv11.1 channel subunit composition includes minK and varies developmentally in mouse cardiac muscle
Authors: Wang Xun , Xu Rongzuo , Abernathey Grant , Taylor Jordan , Alzghoul M.B. , Hannon Kevin , Hockerman Gregory H. , Pond Amber L.
Published: August 2008

The Kv11.1 (also ERG1) K+ channel underlies cardiac IKr, a current that contributes to repolarization in mammalian heart. In mice, IKr current density decreases with development and studies suggest that changes in the structure and/or properties of the heteromultimeric IKr/Kv11.1 channel are responsible. Here, using immunohistochemistry, we report that total Kv11.1 α subunit protein is more abundant in neonatal heart and is distributed throughout both adult and neonatal ventricles with greater abundance in epicardia. Immunoblots reveal that the α subunit alternative splice variant, Kv11.1a, is more abundant in adult heart while the Kv11.1b variant is more abundant in neonatal heart. Additionally, MinK channel subunit protein is shown to co‐assemble with Kv11.1 protein and is more abundant in neonatal heart. In summary, Kv11.1/IKr channel composition varies developmentally and the higher IKr current density in neonatal heart is likely attributable to higher abundance of Kv11.1/IKr channels, more specifically, the Kv11.1b splice variant. Developmental Dynamics 237:2430–2437, 2008. © 2008 Wiley‐Liss, Inc.