bluuebunny/crossref_metadata_2025 huggingface dataset:
Incorporation of prior knowledge in compressed sensing for faster acquisition of hyperpolarized gas images
Authors: Ajraoui S. , Parra‐Robles J. , Wild J. M.
Published: April 2012

Adding prior knowledge to compressed sensing reconstruction can improve image reconstruction. In this work, two approaches are investigated to improve reconstruction of two‐dimensional hyperpolarized 3He lung ventilation images using prior knowledge. When compared against a standard compressed sensing reconstruction, the proposed methods allowed acquisition of images with higher under‐sampling factors and reduction of the blurring effects that increase with higher reduction factors when fixed flip angles are used. These methods incorporate the prior knowledge of polarization decay of hyperpolarized 3He and the mutual anatomical information from a registered 1H image acquired in the same breath. Three times accelerated two‐dimensional images reconstructed with compressed sensing and prior knowledge gave lower root‐mean square error, than images reconstructed without introduction of any prior information. When introducing the polarization decay as prior knowledge, a significant improvement was achieved in the lung region, the root mean square value decreased by 45% and from the whole image by 36%. When introducing the mutual anatomical information as prior knowledge, the root mean square decreased by 21% over the lung region and by 15% over the whole image. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
The effect of temperature on amount and structure of motor variability during 2‐minute maximum voluntary contraction
Authors: Brazaitis Marius , Skurvydas Albertas , Pukėnas Kazimieras , Daniusevic̆iūtė Laura , Mickevic̆ienė Dalia , Solianik Rima
Published: April 2012

Introduction:

In this study, we questioned whether local cooling of muscle or heating involving core and muscle temperatures are the main indicators for force variability.

Methods:

Ten volunteers performed a 2‐min maximum voluntary contraction (MVC) of the knee extensors under control (CON) conditions after passive heating (HT) and cooling (CL) of the lower body.

Results:

HT increased muscle and rectal temperatures, whereas CL lowered muscle temperature but did not affect rectal temperature. During 2‐min MVC, peak force decreased to a lower level in HT compared with CON and CL experiments. Greater central fatigue was found in the HT experiment, and there was less in the CL experiment than in the CON experiment.

Conclusions:

Increased core and muscle temperature increased physiological tremor and the amount and structural complexity of force variability of the exercising muscles, whereas local muscle cooling decreased all force variability variables measured. Muscle Nerve, 2012
Approximate analytical and numerical solutions for radial non‐Darcian flow to a well in a leaky aquifer with wellbore storage and skin effect
Authors: Wen Zhang , Wang Quanrong
Published: April 2012

This study investigated non‐Darcian flow to a well in a leaky aquifer considering wellbore storage and a finite‐thickness skin. The non‐Darcian flow is described by the Izbash equation. We have used a linearization procedure associated with the Laplace transform to solve such a non‐Darcian flow model. Besides, the Stehfest method has been used to invert the Laplace domain solutions for the drawdowns. We further analyzed the drawdowns inside the well for different cases. The results indicated that a smaller BD results in a smaller drawdown at late times and the leakage has little effect on the drawdown inside the well at early times, where BD is a dimensionless parameter reflecting the leakage. We have also found that the flow for the negative skin case approaches the steady‐state earlier than that for the positive skin. In addition, the drawdown inside the well with a positive skin is larger than that without skin effect at late times, and a larger thickness of the skin results in a greater drawdown inside the well at late times for the positive skin case. A reverse result has been found for the negative skin case. Finally, we have developed a finite‐difference solution for such a non‐Darcian flow model and compared the numerical solution with the approximate analytical solution. It has been shown that the linearization procedure works very well for such a non‐Darcian flow model at late times, and it underestimates the drawdowns at early times. Copyright © 2012 John Wiley & Sons, Ltd.
Nicorandil ameliorates hypertension‐related bladder dysfunction in the rat
Authors: Saito Motoaki , Ohmasa Fumiya , Tsounapi Panagiota , Inoue Seiya , Dimitriadis Fotios , Kinoshita Yukako , Satoh Keisuke
Published: April 2012

Aims

There is increasing evidence that ischemia is one of the main etiology in overactive bladder (OAB), and that nicorandil prevents OAB. We investigated the effect of nicorandil on hypertension‐related bladder dysfunction in spontaneously hypertensive rats (SHRs).

Methods

Twelve‐week‐old SHRs received six‐weeks treatment with nicorandil (0, 3, or 10 mg/kg, i.p. every day). Wistar rats were used for normotensive controls. Six weeks after nicorandil treatment, the bladder blood flow was estimated by hydrogen clearance method, and the bladder functions were estimated by voiding behavior studies and functional studies. Tissue levels of nerve growth factor (NGF) were measured by ELISA method. Furthermore, the participation levels of KATP channel pores were investigated by real‐time PCR.

Results

SHRs showed significant increases in blood pressure, micturition frequency, tissue levels of NGF and expressions of both KIR6.1 and KIR6.2 mRNAs, and a significant decrease in the bladder blood flow. The carbachol‐induced contractile responses were similar in all groups. Although both doses of nicorandil failed to decrease the blood pressure, nicorandil significantly decreased the micturition frequency, tissue levels of NGF and increased the bladder blood flow in a dose dependent manner. The expressions of KIR6.1 and KIR6.2 mRNAs were slightly up‐regulated by the low dose of nicorandil, whereas the high dose of nicorandil significantly up‐regulated those expressions compared to non‐treated SHRs.

Conclusions

These data indicate that nicorandil prevents hypertension‐related bladder dysfunction in the SHR, which may be related to its effect on the increased blood flow in the bladder. Neurourol. Urodynam. 31:695–701, 2012. © 2012 Wiley Periodicals, Inc.
Under the tip of the iceberg: Psychological factors in incontinence
Authors: Molinuevo Beatriz , Batista‐Miranda José E.
Published: April 2012

Aims:

To highlight two main psychological factors (cognitive barriers and safety‐behaviors) involved in the development and maintenance of emotional distress in patients with urinary incontinence (UI) and thus facilitate a better understanding of this condition and contribute to a more comprehensive treatment.

Materials and Methods:

Articles and books were reviewed up to December 2010 using a non‐systematic research in MEDLINE and PsycINFO, focusing on the situations more frequently seen in our clinical experience.

Results:

Several emotional symptoms that hinder a person's ability to benefit from urological treatment were found. An “accident” places a person at risk of developing a constant state of heightened worry and increased vigilance that predisposes the individual to develop significant anxiety and depression. Cognitive barriers such as dysfunctional beliefs, automatic negative thoughts, and cognitive biases are frequent. They affect patients' behavior and influence the development of coping strategies (safety‐seeking behaviors) to manage symptoms and prevent feared consequences. Cognitions may act as barriers that lead to a misperception of one's health and maintain emotional distress. Safety behaviors are negatively reinforced and prevent disconfirmation of dysfunctional cognitions, thus maintaining the trouble and distress. Clinical examples are outlined.

Conclusions:

Cognitive barriers and safety behaviors explain some of the atypical psychological patterns seen in patients with UI. Future research should be oriented to design multimodal interventions and assess their impact on health outcomes. Whenever possible, the assessment of emotional, cognitive, and behavioral responses in individuals with UI could improve the management of this condition. Cognitive‐behavioral therapy should be recommended to certain patients. Neurourol. Urodynam. 31:669–671, 2012. © 2012 Wiley Periodicals, Inc.
Brain activity underlying impaired continence control in older women with overactive bladder
Authors: Tadic Stasa D. , Griffiths Derek , Schaefer Werner , Murrin Andrew , Clarkson Becky , Resnick Neil M.
Published: April 2012

Aims

To identify, in subjects with overactive bladder (OAB), differences in brain activity between those who maintained and those who lost bladder control during functional magnetic resonance imaging (fMRI) of the brain with simultaneous urodynamics.

Methods

Secondary analysis of a cohort of older women (aged >60) with proven urgency urinary incontinence, who, in the scanner, either developed detrusor overactivity and incontinence (the “DO group”) or did not (the “no DO” group). A priori hypothesis: during urgency provoked by bladder filling, without DO, activity in regions related to continence control is diminished in the DO group; specifically (1a) less activation in supplementary motor area (SMA) and (1b) less deactivation in prefrontal cortex (PFC) and parahippocampal complex (PH). We also explored phenotypic (clinical and urodynamic) differences between the groups.

Results

During urgency preceding DO, the DO group showed stronger activation in SMA and adjacent regions (hypothesis 1a rejected), and less deactivation in PH but no significant difference in PFC (hypothesis 1b partially accepted). These subjects were older, with more changes in brain's white matter, decreased tolerance of bladder filling and greater burden of incontinence.

Conclusions

(1) In older women with OAB, brain activity in the SMA is greater among those with more easily elicitable DO, suggesting a compensatory response to failure of control elsewhere. (2) OAB is heterogeneous; one possible phenotype shows severe functional impairment attributable partly to age‐related white matter changes. (3) Functional brain imaging coupled with urodynamics may provide CNS markers of impaired continence control in subjects with OAB. Neurourol. Urodynam. 31:652–658, 2012. © 2012 Wiley Periodicals, Inc.
A novel animal model of underactive bladder: Analysis of lower urinary tract function in a rat lumbar canal stenosis model
Authors: Sekido Noritoshi , Jyoraku Akira , Okada Hiroki , Wakamatsu Daisuke , Matsuya Hidekazu , Nishiyama Hiroyuki
Published: April 2012

Aims

An animal model of neurogenic underactive bladder (UAB) has not been established. It was reported that a rat lumbar spinal canal stenosis (LCS) model created by cauda equina compression manifested intermittent claudication and allodynia. In this study, we examined the lower urinary tract function of the rat LCS model.

Methods

One small hole was drilled at the fifth lumbar vertebral arch (sham), and a rectangular piece of silicone rubber was inserted into the L5–L6 epidural space (LCS). Before and after surgery, a metabolic cage study was performed. After surgery, awake cystometry (CMG) and an in vitro muscle strip study were performed. Bladder morphology was evaluated by hematoxylin and eosin staining.

Results

The LCS rats showed a significant decrease in voided volume and a significant increase in postvoid residual volume and residual urine rate compared with Sham rats. CMG showed that the postvoid residual urine volume and numbers of non‐voiding contractions significantly increased, while the voided volume, threshold pressure, and maximum intravesical pressure during voiding significantly decreased. There were no significant differences between sham and LCS rats in response to carbachol. In contrast, there was a significant increase in response to field stimulation, especially at lower frequencies, in LCS rats. LCS rats showed no obvious difference in detrusor morphology.

Conclusions

This rat model requires a relatively simple surgical procedure and has characteristics of neurogenic UAB. It seems to be useful in the pathophysiological elucidation of UAB and might have potential for assessment of pharmacotherapy of UAB. Neurourol. Urodynam. 31:1190–1196, 2012. © 2012 Wiley Periodicals, Inc.
The relationship between pelvic organ prolapse, genital body image, and sexual health
Authors: Zielinski Ruth , Miller Janis , Low Lisa Kane , Sampselle Carolyn , DeLancey John O.L.
Published: April 2012

Aims

Pelvic organ prolapse involves physical changes to the genitals, potentially distressing to women. We hypothesized poorer genital body image in prolapsed women versus controls and that genital body image would correlate with sexual health.

Methods

Seventy‐four sexually active women, 13 with prolapse, 24 with surgically corrected prolapse, 37 without prolapse, completed the Genital Self Image Scale (GSIS‐20), Body Esteem Scale (BES), and Female Sexual Function Index (FSFI).

Results

In prolapsed women median GSIS‐20 scores were 28/40, women with surgically corrected prolapse 32/40 and never prolapsed 34/40 (χ2 = 9.6, P < 0.01). Post hoc analysis showed significant differences between prolapsed and never prolapsed groups (P < 0.05). After adjusting for BES, GSIS‐20 correlated with overall FSFI (r = 0.384, P < 0.01), and its subscales of desire (r =0.34, P < 0.05) and satisfaction (r = 0.41, P < 0.01).

Conclusions

Women with prolapse are at risk for poorer genital body image and reduced sexual health. Neurourol. Urodynam. 31:1145–1148, 2012. © 2012 Wiley Periodicals, Inc.
Variations in Diet and Stature: Are They Linked? Bioarchaeology and Paleodietary Bayesian Mixing Models from Linköping, Sweden
Authors: Arcini Caroline , Ahlström Torbjörn , Tagesson Göran
Published: April 2012

From the early 19th century to the late 20th century, the mean stature of Swedish conscripts increased from 167 to 177 cm. Based on osteological data, estimated statures of medieval skeletal populations indicate that mean stature of males had decreased from an average 173 cm during the medieval period, to 165 cm at the mid 19th century. This change with respect to stature could possibly be linked to the change in diet. Based on the skeletal material unearthed from Linköping, Sweden, we explored the possible association between a changing diet and a decreasing stature. We compared the medieval sample (1100–1300 AD) to a sample dated 1780–1810 AD. A significant multiple regression analysis demonstrates that both sex and chronology explain the variation seen in femur length, but not stable isotopes of carbon and nitrogen. The Bayesian mixing model with uninformative priors suggests that pike is dominating in both the medieval and historical samples, followed by pig, cattle, cod and herring. Using an informative prior based on the consumption from the 16th century Swedish warship Lindormen did not alter the consumption pattern shown by the inhabitants of Linköping. As our results do not suggest a major shift in diet, as well as pointing out lacustrine fish as well as pig as more important to the protein in the diet than cattle, it deviates from what is inferred based on historical records. We conclude that the diet in a town cannot be generalized from the consumption of a ship and probably not from institutions either. These contexts have dominated the reconstructions of 19th century diet in Sweden based on historical records. However, there is also the possibility that the two isotopes employed are not sufficiently delicate to detect such dietary changes. Copyright © 2012 John Wiley & Sons, Ltd.
Congenital and Childhood myeloproliferative disorders with eosinophilia responsive to imatinib
Authors: Abraham Shirley , Salama Mohamed , Hancock Jeffrey , Jacobsen Jeffrey , Fluchel Mark
Published: April 2012

Eosinophilia is seen in several myeloproliferative disorders (MPD). A subset of MPD involves the platelet‐derived growth factor receptor beta (PDGFRB) gene. Imatinib mesylate has been efficacious in treating some of these MPDs. Here we describe two patients with MPD with eosinophilia and PDGFRB rearrangements, one of which was congenital. Both patients were treated with single agent imatinib and continue to be in clinical, hematologic, and cytogenetic remission despite weaning doses. No definite guidelines currently exist regarding the exact dosing and duration of imatinib therapy for these patients. Pediatr Blood Cancer 2012; 59: 928–929. © 2012 Wiley Periodicals, Inc.
Surgical complications in pediatric surgical oncology
Authors: Warmann Steven W. , Seitz Guido , Fuchs Jörg
Published: April 2012

Rates of surgical complications in pediatric oncological patients increase with the extension of tumor surgery. Especially in advanced tumors this can mean a relevant challenge to surgeons: The balance between risk of complications and success of surgical treatment is often difficult to accomplish. As a consequence, surgeons not only need profound knowledge about resection techniques and surgical standard procedures but they also have to be able to control and manage surgical complications during and after surgery. This article highlights background and spectrum as well as management of selected surgical complications during or after surgery for abdominal pediatric solid tumors. Pediatr Blood Cancer 2012;59:398–404. © 2012 Wiley Periodicals, Inc.
Investigation on mechanical and tribological behavior of naturally woven coconut sheath‐reinforced polymer composites
Authors: Siva Irullappasamy , Jappes Jebas Thangiah Winowlin , Suresha Bheemappa
Published: April 2012

The article presents the results of experimental investigation on mechanical and dry sliding wear behavior of unsaturated polyester resin (USP), reinforced with naturally woven coconut sheath and glass fibers. The mechanical properties of coconut sheath (N) and glass fiber (G) reinforced polyester composites were studied, and the tribological behaviors were tested on pin‐on‐disc sliding wear tester. Mass loss was determined as a function of sliding distance for a sliding velocity of 3.5 m/s and an applied normal load of 40 N. The experimental result revealed that the mechanical properties and wear resistance of the composites depend on the wt% reinforcement of coconut sheath/glass fiber and sliding distance. The hybrid reinforcement (GGN) greatly increased the mechanical properties of USP. At lower sliding distance, the N‐reinforced USP had lower wear loss, whereas at higher sliding distance, the hybrid fiber‐reinforced (GGN) USP composite had lower wear loss. Furthermore, the work showed that the higher sliding distance bring about changes in the worn surface features such as interface separation, inclined fracture of fibers, loss of matrix, and the appearance of debris with the two different fibers. The worn surfaces were also examined by scanning electron microscopy. The study showed differing trends with load for the two types of reinforcements. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Noninvasive prenatal diagnosis empowered by high‐throughput sequencing
Authors: Chiu Rossa W. K. , Lo Y. M. Dennis
Published: April 2012

Background

Noninvasive prenatal diagnosis of fetal Down syndrome using direct nucleic acid analysis was once an elusive goal. The presence of cell‐free fetal DNA in maternal plasma was discovered in 1997 and offered a new noninvasive source of fetal genetic material.

Method

A number of approaches have since been developed for the assessment of fetal chromosome dosage based on cellfree fetal DNA analysis. The most effective approach developed to date is based on massively parallel sequencing of maternal plasma DNA molecules for the detection of an increased representation of chromosome 21 DNA molecules in the plasma of women pregnant with trisomy 21 fetuses when compared with euploid pregnancies.

Result and Conclusion

A number of multicenter studies have since been conducted to evaluate the diagnostic efficacy of the sequencing‐based method. To date, the literature contains results for the analysis of a total of 305 trisomy 21 pregnancies and 2061 euploid pregnancies. The overall diagnostic sensitivity and specificity were both 99%. Besides trisomy 21, massively parallel maternal plasma DNA sequencing has also been applied to the noninvasive detection of trisomy 18, trisomy 13 and fetal genetic sequences across the genome. © 2012 John Wiley & Sons, Ltd.
Associations of Identity Dimensions with Big Five Personality Domains and Facets
Authors: Klimstra Theo A. , Luyckx Koen , Goossens Luc , Teppers Eveline , De Fruyt Filip
Published: April 2012

Personality is among the most important factors contributing to individual differences in identity formation. However, previous studies mainly focused on broad personality domains and neglected more specific facets. In addition, it has only recently been recognized that identity formation is guided by multiple types of commitment and exploration. The present study aimed to remedy these limitations by relating the 30 personality facets of the NEO–PI–3 to five identity dimensions. In general, identity formation was especially facilitated by high levels of Conscientiousness and, to a lesser extent, also by high levels of Extraversion and low levels of Neuroticism. Openness and Agreeableness predicted greater involvement in both the positive side (i.e. exploration in breadth and depth) and negative side (i.e. ruminative exploration) of the exploration process. Personality facets and their overarching domains, as well as facets underlying the same domain, were often differentially associated with identity dimensions. Additionally, we found that some personality facets both have bright and dark sides, as they predicted both proactive identity work and a weakened sense of identity. Overall, the present study underscores the utility of multidimensional models of identity formation and points to the benefits of considering personality facets in addition to broad domains. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis of amphiphilic A2B star‐shaped copolymers of polystyrene‐b‐[poly(ethylene oxide)]2 via atom transfer nitroxide radical coupling
Authors: Huang Kun , Huang Jian , Pan Mugang , Wang Guowei , Huang Junlian
Published: April 2012

The amphiphilic A2B star‐shaped copolymers of polystyrene‐b‐[poly(ethylene oxide)]2 (PS‐b‐PEO2) were synthesized via the combination of atom transfer nitroxide radical coupling (ATNRC) with ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP) mechanisms. First, a novel V‐shaped 2,2,6,6‐tetramethylpiperidine‐1‐oxyl‐PEO2 (TEMPO‐PEO2) with a TEMPO group at middle chain was obtained by ROP of ethylene oxdie monomers using 4‐(2,3‐dihydroxypropoxy)‐TEMPO and diphenylmethyl potassium as coinitiator. Then, the linear PS with a bromine end group (PS‐Br) was obtained by ATRP of styrene monomers using ethyl 2‐bromoisobutyrate as initiator. Finally, the copolymers of PS‐b‐PEO2 were obtained by ATNRC between the TEMPO and bromide groups on TEMPO‐PEO2 and PS‐Br, respectively. The structures of target copolymers and their precursors were all well‐defined by gel permeation chromatographic and nuclear magnetic resonance (1H NMR). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Reliable stretchable gold interconnects in biocompatible elastomers
Authors: Jahanshahi A. , Salvo P. , Vanfleteren J.
Published: April 2012

One of the key issues in realization of stretchable and curvilinear electronics is the fabrication of stretchable interconnects. Stretchable interconnects are basically conductor lines embedded in elastomer substrates. Currently, metal interconnects embedded in polydimethylsiloxane are one of the major candidates. In this work, a novel straightforward method is presented that allows the fabrication of 20 μm wide stretchable gold interconnects starting from commercial double sided flexes (Cu–PI–Cu). These interconnects are still fully functional after a minimum of 100 k cycles at 40% elongation. In addition to outstanding reliability in this method of fabrication, fine pitch and biocompatibility are the added values paving the way for medical grade stretchable electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Managing treatment complexity in cystic fibrosis: Challenges and Opportunities
Authors: Sawicki Gregory S. , Tiddens Harm
Published: April 2012

Cystic fibrosis (CF) is a complex, chronic, multisystem disease for which there is currently no cure. Nonetheless, advances in management have led to dramatic improvements in patient survival. With this development, new issues have arisen for CF patients and their care providers, including an increased symptom burden and increased frequency of co‐morbidities as patients reach older ages, leading to the need for a highly complicated and time‐consuming regimen of treatments. Such high symptom and treatment burden often leads to non‐adherence and low levels of competence with administration of therapy, both of which may have detrimental impacts on CF outcomes. Optimal management is also hindered by other patient‐related factors, including inadequacies in disease education which may lead to issues with self‐management. This is particularly important during the transition from parent‐directed therapy to independent self‐management that occurs during adolescence and early adulthood. Clinicians are also faced with a considerable challenge when selecting interventions for individual patients; although the paradigm of aggressive care necessitates a wide range of therapies, there is a limited evidence base with which to compare available therapeutic regimens. Novel pharmacological agents are being developed to target the underlying cause of CF, while non‐pharmacological interventions aim to improve competence and maximize adherence and health outcomes. Comparative effectiveness research is needed to simplify management and facilitate the implementation of appropriate treatment strategies. Pediatr Pulmonol. 2012; 47:523–533. © 2012 Wiley Periodicals, Inc.
Synthesis and Characterization of 3,3′‐Bisazidomethyl Oxetane‐3‐Azidomethyl‐3′‐Methyl Oxetane Alternative Block Energetic Thermoplastic Elastomer
Authors: Zhang Chi , Li Jie , Luo Yunjun
Published: April 2012

3,3′‐Bisazidomethyl oxetane‐3‐azidomethyl‐3′‐methyl oxetane (BAMO‐AMMO) tri‐block copolymer was successfully synthesized by azidation of a polymeric substrate containing bromo leaving groups, and an alternative block energetic thermoplastic elastomer (ETPE) was prepared by chain extension reaction. The tri‐block copolymer was characterized by Fourier transform infrared (FTIR), 1H NMR, and 13C NMR spectroscopy, X‐ray diffraction (XRD), and thermogravimetric analysis (TGA). It was found that the composition of the copolymer is nearly 1 : 1; crystallinity of the copolymer (71.81 %) is less than that of PBAMO (78.30 %). This is due to a partly mixture between soft and hard segments. Kinetic result shows that a crosslinking network is formed after the decomposition of azide group. Tensile strength of alternative block ETPE is 150 % of traditionally synthesized BAMO‐AMMO ETPE.
Purification, characterization of a CkChn134 protein from Cynanchum komarovii seeds and synergistic effect with CkTLP against Verticillium dahliae
Authors: Wang Qinghua , Zhang Yongan , Hou Yuxia , Wang Ping , Zhou Sihong , Ma Xiaowen , Zhang Ning
Published: April 2012

Cynanchum komarovii Al Iljinski is a desert plant that has been used as analgesic, anthelminthic, and antidiarrheal, but also as herbal medicine to treat cholecystitis in people. In this work, an antifungal protein with sequence homology to chitinase was isolated from C. komarovii seeds and named CkChn134. The three‐dimensional structure prediction of CkChn134 indicated that the protein has a loop domain formed a thin cleft, which is able to bind molecules and substrates. The protein and CkTLP synergistically inhibited the fungal growth of Verticillium dahliae, Fusarium oxysporum, Rhizoctonia solani, Botrytis cinerea, and Valsa mali in vitro. The full‐length cDNA was cloned by RT‐PCR and RACE‐PCR according to the partial protein sequences obtained by nanoESI‐MS/MS. The real‐time PCR showed that the transcription level of CkChn134 had a significant increase under the stress of ethylene, NaCl, low temperature, drought, and pathogen infection, which indicates that CkChn134 may play an important role in response to abiotic and biotic stresses. The CkChn134 protein was located in the extracellular space/cell wall by CkChn134::GFP fusion protein in transgenic Arabidopsis. Furthermore, overexpression of CkChn134 significantly enhanced the resistance of transgenic Arabidopsis against V. dahliae. Interestingly, the coexpression of CkChn134 and CkTLP showed substantially greater protection against the fungal pathogen V. dahliae than either transgene alone. The results suggest that the CkChn134 is a good candidate protein or gene, and it had a potential synergistic effect with CkTLP for contributing to the development of disease‐resistant crops.
Effects of lysophosphatidic acid on calpain‐mediated proteolysis of focal adhesion kinase in human prostate cancer cells
Authors: Park Joshua J. , Rubio Maria V. , Zhang Zhihong , Um Tae , Xie Yuhuan , Knoepp Stewart M. , Snider Ashley J. , Gibbs Terra C. , Meier Kathryn E.
Published: April 2012

BACKGROUND

Calcium‐mediated proteolysis plays an important role in cell migration. Lysophosphatidic acid (LPA), a lipid mediator present in serum, enhances migration of carcinoma cells. The effects of LPA on calpain‐mediated proteolysis were, therefore, examined in PC‐3, a human prostate cancer cell line.

METHODS

Cultured PC‐3 cells were used in studies utilizing pharmacologic interventions, immunoblotting, and confocal immunolocalization.

RESULTS

Focal adhesion kinase (FAK), a tyrosine kinase involved in cell adhesion, is rapidly proteolyzed in serum‐starved PC‐3 cells exposed to the calcium ionophore, ionomycin; Nck, p130CAS, PKCα, and Ras‐GAP are also degraded. Thapsigargin, which causes more moderate increases in intracellular calcium, induces partial proteolysis of these proteins. Calpain inhibitors block the proteolytic responses to ionomycin and thapsigargin. Ionomycin does not induce proteolysis in cells maintained in serum, suggesting a protective role for growth factors contained in serum. LPA causes minor FAK proteolysis when added alone, but protects against ionomycin‐induced proteolysis in a time‐dependent manner. LPA also protects against the cell detachment that eventually follows ionomycin treatment. The response to LPA is blocked by an LPA receptor antagonist. A similar effect of LPA is observed in ionomycin‐treated Rat‐1 fibroblasts. In PC‐3 cells, the protective effects of LPA and serum are correlated with phosphorylation and redistribution of paxillin, suggesting roles for phosphorylation‐mediated protein–protein interactions.

CONCLUSIONS

The complex effects of LPA on calpain‐mediated proteolysis of FAK and other adhesion proteins are likely to play a role in the ability of LPA to promote attachment, migration, and survival of prostate cancer cells. Prostate 72:1595–1610, 2012. © 2012 Wiley Periodicals, Inc.
The Monoamine Oxidase A gene promoter repeat and prostate cancer risk
Authors: White Thomas A. , Kwon Erika M. , Fu Rong , Lucas Jared M. , Ostrander Elaine A. , Stanford Janet L. , Nelson Peter S.
Published: April 2012

BACKGROUND

Amine catabolism by monoamine oxidase A (MAOA) contributes to oxidative stress, which plays a role in prostate cancer (PCa) development and progression. An upstream variable‐number tandem repeat (uVNTR) in the MAOA promoter influences gene expression and activity, and may thereby affect PCa susceptibility.

METHODS

Caucasian (n = 2,572) men from two population‐based case‐control studies of PCa were genotyped for the MAOA‐VNTR. Logistic regression was used to assess PCa risk in relation to genotype.

RESULTS

Common alleles of the MAOA‐VNTR were not associated with the relative risk of PCa, nor did the relationship differ by clinical features of the disease. The rare 5‐copy variant (frequency: 0.5% in cases; 1.8% in controls), however, was associated with a reduced PCa risk (odds ratio, OR = 0.30, 95% CI 0.13–0.71).

CONCLUSIONS

A rare polymorphism of the MAOA promoter previously shown to confer low expression was associated with a reduced risk of developing PCa. This novel finding awaits confirmation in other study populations. Prostate 72:1622–1627, 2012. © 2012 Wiley Periodicals, Inc.
MUC1‐C oncoprotein confers androgen‐independent growth of human prostate cancer cells
Authors: Rajabi Hasan , Ahmad Rehan , Jin Caining , Joshi Maya Datt , Guha Minakshi , Alam Maroof , Kharbanda Surender , Kufe Donald
Published: April 2012

BACKGROUND

The mucin 1 (MUC1) heterodimeric oncoprotein is overexpressed in human prostate cancers with aggressive pathologic and clinical features. However, few insights are available regarding the functional role of MUC1 in prostate cancer.

METHODS

Effects of MUC1‐C on androgen receptor (AR) expression were determined by RT‐PCR, immunoblotting and AR promoter activation. Coimmunoprecipitations, direct binding assays, and chromatin immunoprecipitation (ChIP) studies were performed to assess the interaction between MUC1‐C and AR. Cells were analyzed for invasion, growth in androgen‐depleted medium, and sensitivity to MUC1‐C inhibitors.

RESULTS

The present studies in androgen‐dependent LNCaP and LAPC4 prostate cancer cells demonstrate that the oncogenic MUC1‐C subunit suppresses AR expression. The results show that MUC1‐C activates a posttranscriptional mechanism involving miR‐135b‐mediated downregulation of AR mRNA levels. The results further demonstrate that MUC1‐C forms a complex with AR through a direct interaction between the MUC1‐C cytoplasmic domain and the AR DNA‐binding domain (DBD). In addition, MUC1‐C associates with AR in a complex that occupies the PSA promoter. The interaction between MUC1‐C and AR is associated with induction of the epithelial‐mesenchymal transition (EMT) and increased invasion. MUC1‐C also conferred growth in androgen‐depleted medium and resistance to bicalutamide treatment. Moreover, expression of MUC1‐C resulted in sensitivity to the MUC1‐C inhibitor GO‐203 with inhibition of growth in vitro. GO‐203 treatment also inhibited growth of established tumor xenografts in nude mice.

CONCLUSIONS

These findings indicate that MUC1‐C suppresses AR expression in prostate cancer cells and confers a more aggressive androgen‐independent phenotype that is sensitive to MUC1‐C inhibition. Prostate 72:1659–1668, 2012. © 2012 Wiley Periodicals, Inc.
Free radical scavenging activity of caffeine's metabolites
Authors: León‐Carmona Jorge Rafael , Galano Annia
Published: April 2012

The reactions of caffeine's main metabolites [paraxanthine, theobromine, theophylline, and 1‐methylxanthine] with •OH, •OCH3, •OOH, and •OOCH3, in nonpolar and polar environments, have been studied using the density functional theory. Different mechanisms of reaction have been taken into account and their relative importance on the antioxidant activity of these compounds has been assessed. The free radical scavenging activity of the studied metabolites was found to be excellent for •OH, moderate for •OCH3, and negligible for peroxy radicals. The results from the present work indicate that the antioxidant activity of caffeine in our body remains almost the same when metabolized to paraxanthine, theobromine, theophylline, and 1‐methylxanthine, while it is increased after being metabolized to 1‐methyluric acid. In addition, the polarity of the environment was found to affect the overall reactivity of the studied compounds, to influence the relative importance of the different mechanisms and channels of reaction, and to have negligible effects on the relative scavenging activity of the studied compounds (theobromine > paraxanthine ≈ theophylline ≈ 1‐methylxanthine). The studied metabolites were found to be better scavengers in nonpolar media than in aqueous solution. © 2012 Wiley Periodicals, Inc.
Conical intersection structure and dynamics for a model protonated schiff base photoisomerization in solution
Authors: Malhado João Pedro , Spezia Riccardo , Hynes James T.
Published: April 2012

Here, we present some highlights of our recent study [Malhado et al. J. Phys. Chem. A 115, 3729 (2011)] of the photoisomerization involving a conical intersection for a model protonated Schiff base (PSB) in modeled water and acetonitrile solvents, in which the inclusion of energy‐ and momentum‐transfer effects is described via a generalized Langevin equation (GLE) frictional approach and surface‐hopping dynamics. Short‐time GLE frictional effects on the model's three coordinates, the intramolecular bond length alternation, and torsional PSB coordinates and a solvent coordinate, have a number of important features. Among these are the general feature of accelerating nonadiabatic transitions to the ground electronic state and a predicted preferential higher proportion of ground‐state trans isomer, that is, a successful cis to trans photoreaction. This preference is solvent‐dependent and is enhanced in water solvent with its higher friction intensity and short time scales. © 2012 Wiley Periodicals, Inc.
An iterative algorithm for maximizing robust performance in loop‐shaping design
Authors: Osinuga M. , Patra S. , Lanzon A.
Published: April 2012

In this paper, an algorithm that gives the best achievable performance bound on a given control problem is proposed using the loop‐shaping design framework. In view of standard design requirements, the robust performance is maximized at low and high frequencies while keeping the robust stability margin above a specified level, and the robust stability margin is directly improved at mid frequencies (around crossover). The proposed frequency‐dependent optimization problem is cast in an LMI framework. The resulting solution algorithm simultaneously synthesizes loop‐shaping weights and a stabilizing controller that achieve the maximum performance for a given level of robust stability margin corresponding to sufficient gain and phase margins of the closed‐loop system. Copyright © 2012 John Wiley & Sons, Ltd.
Equivalence of sum of squares convex relaxations for quadratic distance problems
Authors: Garulli Andrea , Masi Alfio , Vicino Antonio
Published: April 2012

This paper deals with convex relaxations for quadratic distance problems, a class of optimization problems relevant to several important topics in the analysis and synthesis of robust control systems. Some classes of convex relaxations are investigated using the sum of squares paradigm for the representation of positive polynomials. The main contribution is to show that two different relaxations, based respectively on the Positivstellensatz and on properties of homogeneous polynomial forms, are equivalent. Relationships among the considered relaxations are discussed and numerical comparisons are presented, highlighting their degree of conservatism. Copyright © 2012 John Wiley & Sons, Ltd.
Robust stability of nonlinear model predictive control with extended Kalman filter and target setting
Authors: Huang Rui , Patwardhan Sachin C. , Biegler Lorenz T.
Published: April 2012

This work deals with the closed‐loop robust stability of nonlinear model predictive control (NMPC) coupled with an extended Kalman filter (EKF). First, we point out the gaps between the practical formulations and theoretical research. Then, we show that the estimation error dynamics of an EKF are input‐to‐state stable (ISS) in the presence of nonvanishing perturbations. Moreover, a target setting optimization problem is proposed to solve the target state corresponding to the desired set points, which are used in the objective function in NMPC formulation. Thus, the objective function is a Lyapunov function candidate, and the input‐to‐state practical stability (ISpS) of the closed‐loop system can be established. Moreover, we see that the stability property deteriorates because of the estimation error. Simulation results of the proposed scheme are presented.Copyright © 2012 John Wiley & Sons, Ltd.
Receptor Activator of NF-κB Ligand Promotes Proliferation of a Putative Mammary Stem Cell Unique to the Lactating Epithelium
Authors: Thomas Elizabeth , Lee-Pullen Tracey , Rigby Paul , Hartmann Peter , Xu Jiake , Zeps Nikolajs
Published: April 2012

In mice, CD49fhi mammary stem cells (MaSCs) asymmetrically divide to generate CD49f+ committed progenitor cells that differentiate into CD49f− phenotypes of the milk-secreting tissue at the onset of pregnancy. We show CD49f+ primary mammary epithelial cells (PMECs) isolated from lactating tissue uniquely respond to pregnancy-associated hormones (PAH) compared with CD49f+ cells from nonlactating tissue. Differentiation of CD49f+ PMEC in extracellular matrix produces CD49f− luminal cells to form differentiated alveoli. The PAH prolactin and placental lactogen specifically stimulate division of CD49f− luminal cells, while receptor activator of nuclear factor (NF)-κB ligand (RANKL) specifically stimulates division of basal CD49f+ cells. In nondifferentiating conditions, we observed a greater proportion of multipotent self-renewing cells, and RANKL treatment activated the RANK pathway in these cultures. Furthermore, we observed the deposition of calcium nodules in a proportion of these cells. These data imply that a MaSC unique to the lactating breast exists in humans, which generates progeny with discrete lineages and distinct response to PAH.

Disclosure of potential conflicts of interest is found at the end of this article.
Human Epithelial Basal Cells Are Cells of Origin of Prostate Cancer, Independent of CD133 Status
Authors: Taylor Renea A. , Toivanen Roxanne , Frydenberg Mark , Pedersen John , Harewood Laurence , Australian Prostate Cancer Bioresource  , Collins Anne T. , Maitland Norman J. , Risbridger Gail P.
Published: April 2012

Normal prostatic epithelium is composed of basal and luminal cells. Prostate cancer can be initiated in both benign basal and luminal stem cells, but because basal cell markers are not expressed in patient tumors, the former result was unexpected. Since the cells of origin of prostate cancer are important therapeutic targets, we sought to provide further proof that basal stem cells have tumorigenic potential. Prostatic basal cells were enriched based on α2β1integrinhi expression and further enriched for stem cells using CD133 in nontumorigenic BPH-1 cells. Human embryonic stem cells (hESCs) were also used as a source of normal stem cells. To test their tumorigenicity, we used two alternate stromal-based approaches; (a) recombination with human cancer-associated fibroblasts (CAFs) or (b) recombination with embryonic stroma (urogenital mesenchyme) and treated host mice with testosterone and 17β-estradiol. Enriched α2β1integrinhi basal cells from BPH-1 cells resulted in malignant tumor formation using both assays of tumorigenicity. Surprisingly, the tumorigenic potential did not reside in the CD133+ stem cells but was consistently observed in the CD133− population. CAFs also failed to induce prostatic tumors from hESCs. These data confirmed that benign human basal cells include cells of origin of prostate cancer and reinforced their importance as therapeutic targets. In addition, our data suggested that the more proliferative CD133− basal cells are more susceptible to tumorigenesis compared to the CD133+-enriched stem cells. These findings challenge the current dogma that normal stem cells and cells of origin of cancer are the same cell type(s).

Disclosure of potential conflicts of interest is found at the end of this article.
Young black children and science: Chronotopes of narratives around their science journals
Authors: Varelas Maria , Kane Justine M. , Wylie Caitlin D.
Published: April 2012

We explored 30 Black Kindergarten‐2nd grade students' spoken narratives around pages of their science journals that the children selected asbestfor showing them as scientists. Because in all narratives, space–time relationships play an important role not only in situating but also in constituting them, we focused on such relationships using Bakhtin's (1981) construct of chronotopes. Our chronotopical analysis aimed at fleshing out the temporal and spatial features that were present in the children's journal pages, and in the children's ways of talking both about these features and about being scientists. Our goal was to better understand ways in which African‐American children identify with science and scientists in particular contexts: an interview with an adult who had visited their class throughout that year and a class where they were offered various opportunities to engage with science. Using six cases that maximized the variety of understandings we could develop vis‐à‐vis our research question, we show how the children's narratives were filled with differing space–time relationships in which the children found ways to showcase their agency. Thus, we provide insights into how the children authored relationships with science and scientists, negotiated the past with the present and possible future, and contextualized their narratives within various time‐spaces that had meaning for them. Moreover, multiple people populated the children's chronotopes and became intertwined with the space–time relationships that underlined their conceptions of themselves vis‐à‐vis science and scientists. Despite the varied conceptions of science and scientists that the children portrayed, their narratives communicated a high level of confidence in being able to do science and be scientists, and initiative in learning. The children's narratives were filled with hope, “able‐ness,” knowledge, affect, and possibility. These findings point to several considerations for practice. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 568–596, 2012
Recent progress in perceptual learning research
Authors: Sasaki Yuka , Náñez José E. , Watanabe Takeo
Published: April 2012

Perceptual learning is defined as long‐term improvement in perceptual or sensory systems resulting from repeated practice or experience. As the number of perceptual learning studies has increased, controversies and questions have arisen regarding divergent aspects of perceptual learning, including: (1) stages in which perceptual learning occurs, (2) effects of training type, (3) changes in neural processing during the time course of learning, (4) effects of feedback as to correctness of a subject's responses, and (5) double training. Here we review each of these aspects and suggest fruitful directions for future perceptual learning research. WIREs Cogn Sci 2012, 3:293–299. doi: 10.1002/wcs.1175

This article is categorized under:

Psychology > Perception and Psychophysics
Molecular mechanisms of liver and bile duct development
Authors: Zong Yiwei , Stanger Ben Z.
Published: April 2012

The liver is derived from the ventral foregut endoderm. After hepatic specification, liver progenitor cells delaminate from the endoderm and invade the septum transversum mesenchyme to form the liver bud. In addition to proliferation and expansion, liver progenitor cells differentiate into two epithelial cell types, each arranged into unique structures with distinctive function. Growth, morphogenesis, and differentiation during liver development are regulated by a variety of factors that are expressed in a spatially and temporally specific manner. A comprehensive understanding of the regulatory mechanisms underlying the liver development has influenced the diagnosis of liver diseases and further progress will be critical for future advances in therapy. This review highlights some of the best understood steps of liver development, summarizing progress in our understanding of the molecular mechanisms that underlie differentiation, morphogenesis, and functional integration of the liver. WIREs Dev Biol 2012 doi: 10.1002/wdev.47

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