bluuebunny/crossref_metadata_2025 huggingface dataset:
Paxillin's LD4 motif interacts with bcl‐2
Authors: Sheibani Nader , Tang Yixin , Sorenson Christine M.
Published: September 2007

bcl‐2 is the founding member of a family of proteins which influences cell survival in response to a variety of stimuli including those from growth factor receptors and integrins. However, how these activities are coordinated through bcl‐2 requires further investigation. bcl‐2 interacts with paxillin, potentially linking cell survival and cell adhesive pathways. Paxillin is an adapter protein implicated in growth factor and integrin‐mediated signal transduction pathways. Previous work in this laboratory demonstrated that loss of bcl‐2 affects cell adhesion and migration characteristics of renal epithelial cells, perhaps through disruption of its interaction with paxillin. Here studies were performed to determine the bcl‐2 binding motif in paxillin. The amino‐terminal portion of paxillin, specifically its LD4 motif, was found to associate with bcl‐2. However, the amino‐terminal portion of paxillin with the LD4 domain deleted did not associate with bcl‐2. The corresponding LD motif in other paxillin family members, Hic‐5 and leupaxin, did not associate with bcl‐2. Mutations in paxillin's LD4 motif made to mimic Hic‐5 and leupaxin LD4‐like motifs (E268 → R or S272 → H) abolished its association with bcl‐2. Incubation of embryonic kidneys with paxillin's LD4 motif disrupted ureteric bud branching and morphogenesis, while incubation with the comparable Hic‐5 LD motif did not significantly affect morphogenesis. These data suggest that paxillin's association with bcl‐2 plays a unique role during kidney development that other paxillin family members may not be able to fulfill. J. Cell. Physiol. 214: 655–661, 2008. © 2007 Wiley‐Liss, Inc.
Ajulemic acid, a nonpsychoactive cannabinoid acid, suppresses osteoclastogenesis in mononuclear precursor cells and induces apoptosis in mature osteoclast‐like cells
Authors: George Kerri L. , Saltman Laura H. , Stein Gary S. , Lian Jane B. , Zurier Robert B.
Published: September 2007

Oral administration of ajulemic acid (AjA), a cannabinoid acid devoid of psychoactivity, prevents joint tissue injury in rats with adjuvant induced arthritis. Because activation of osteoclasts is central to the pathogenesis of bone erosion in patients with rheumatoid arthritis (RA), we investigated the influence of AjA on osteoclast differentiation and survival. Osteoclast cultures were established by stimulation of RAW264.7 cells and primary mouse bone marrow cultures with receptor activator of NF‐κB ligand (RANKL). Simultaneous addition of AjA (15 and 30 µM) and RANKL to both culture systems significantly suppressed development of multinucleated osteoclasts (osteoclastogenesis) in a dose dependent manner, as determined by quantification of multinuclear, tartrate‐resistant acid phosphatase (TRAP)‐positive cells. AjA impaired growth of RAW264.7 monocytes and prevented further osteoclast formation in cultures in which osteoclastogenesis had already begun. Reduction by AjA of both monocyte growth and osteoclast formation was associated with apoptosis, assayed by annexin V and propidium iodide staining, and caspase activity. The anti‐osteoclastogenic effects of AjA did not require the continuous presence of AjA in the cell cultures. Based on these findings, we propose that AjA or other nonpsychoactive synthetic analogs ofCannabisconstituents may be useful therapy for diseases such as RA and osteoporosis in which bone resorption is a central feature. J. Cell. Physiol. 214: 714–720, 2008. © 2007 Wiley‐Liss, Inc.
HDLs activate ADAM17‐dependent shedding
Authors: Tellier Edwige , Canault Matthias , Poggi Marjorie , Bonardo Bernadette , Nicolay Alain , Alessi Marie‐Christine , Nalbone Gilles , Peiretti Franck
Published: September 2007

The tumor necrosis factor‐alpha (TNF) converting enzyme (ADAM17) is a metalloprotease that cleaves several transmembrane proteins, including TNF and its receptors (TNFR1 and TNFR2). We recently showed that the shedding activity of ADAM17 is sequestered in lipid rafts and that cholesterol depletion increased the shedding of ADAM17 substrates. These data suggested that ADAM17 activity could be regulated by cholesterol movements in the cell membrane. We investigated if the membrane cholesterol efflux induced by high‐density lipoproteins (HDLs) was able to modify the shedding of ADAM17 substrates. HDLs added to different cell types, increased the ectodomain shedding of TNFR2, TNFR1, and TNF, an effect reduced by inhibitors active on ADAM17. The HDLs‐stimulated TNF release occurred also on cell‐free isolated plasma membranes. Purified apoA1 increased the shedding of TNF in an ABCA1‐dependent manner, suggesting a role for the cholesterol efflux in this phenomenon. HDLs reduced the cholesterol and proteins (including ADAM17) content of lipid rafts and triggered the ADAM17‐dependent cleavage of TNF in the non‐raft region of the membrane. In conclusion, these data demonstrate that HDLs alter the lipid raft structure, which in turn activates the ADAM17‐dependent processing of transmembrane substrates. J. Cell. Physiol. 214: 687–693, 2008. © 2007 Wiley‐Liss, Inc.
1α,25‐dihydroxy vitamin D3‐enhanced expression of the osteocalcin gene involves increased promoter occupancy of basal transcription regulators and gradual recruitment of the 1α,25‐dihydroxy vitamin D3 receptor‐SRC‐1 coactivator complex
Authors: Carvallo Loreto , Henríquez Berta , Paredes Roberto , Olate Juan , Onate Sergio , van Wijnen Andre J. , Lian Jane B. , Stein Gary S. , Stein Janet L. , Montecino Martin
Published: September 2007

Binding of 1α,25‐dihydroxy vitamin D3 to the C‐terminal ligand‐binding domain (LBD) of its receptor (VDR) induces a conformational change that enables interaction of VDR with transcriptional coactivators such as members of the p160/SRC family or the DRIP (vitamin D receptor‐interacting complex)/Mediator complex. These interactions are critical for VDR‐mediated transcriptional enhancement of target genes. The p160/SRC members contain intrinsic histone acetyl transferase (HAT) activities that remodel chromatin at promoter regulatory regions, and the DRIP/Mediator complex may establish a molecular bridge between the VDR complex and the basal transcription machinery. Here, we have analyzed the rate of recruitment of these coactivators to the bone‐specific osteocalcin (OC) gene in response to short and long exposures to 1α,25‐dihydroxy vitamin D3. We report that in intact osteoblastic cells VDR, in association with SRC‐1, rapidly binds to the OC promoter in response to the ligand. The recruitment of SRC‐1 correlates with maximal transcriptional enhancement of the OC gene at 4 h and with increased histone acetylation at the OC promoter. In contrast to other 1α,25‐dihydroxy vitamin D3‐enhanced genes, binding of the DRIP205 subunit, which anchors the DRIP/Mediator complex to the VDR, is detected at the OC promoter only after several hours of incubation with 1α,25‐dihydroxy vitamin D3, concomitant with the release of SRC‐1. Together, our results support a model where VDR preferentially recruits SRC‐1 to enhance bone‐specific OC gene transcription. J. Cell. Physiol. 214: 740–749, 2008. © 2007 Wiley‐Liss, Inc.
Differential signaling mechanisms of HNP‐induced IL‐8 production in human lung epithelial cells and monocytes
Authors: Syeda Farisa , Liu Hui‐Yu , Tullis Elizabeth , Liu Mingyao , Slutsky Arthur S. , Zhang Haibo
Published: September 2007

Human neutrophil peptides (HNP) kill microorganisms but also modulate immune responses through upregulation of the chemokine IL‐8 by activation of the nucleotide P2Y6 receptor. However, the intracellular signaling mechanisms remain yet to be determined. Human lung epithelial cells (A549) and monocytes (U937) were stimulated with HNP in the absence and presence of the specific kinase inhibitors for Src, extracellular signal‐regulated kinase‐1 and ‐2 (ERK1/2), p38 mitogen‐activated protein kinase (MAPK), c‐Jun‐N‐terminal kinases (JNK), and Akt. HNP induced a rapid phosphorylation of the kinases in both cell types associated with a dose‐dependent, selective production of IL‐8 among 10 cytokines assayed. The HNP‐induced IL‐8 production was blocked by the Src tyrosine kinase inhibitor PP2, MEK1/2 inhibitor U0126, and the phosphatidylinositol 3 kinase (PI3K) inhibitor LY294002, but not by the JNK inhibitor SP600125 in both cell types. Treatment with the p38 inhibitor SB203580 attenuated the HNP‐induced IL‐8 production only in monocytes. Blockade of Src kinase blunted HNP‐induced phosphorylation of the ERK1/2 and Akt but not p38 in monocytes. In contrast, Src inhibition had no effect on phosphorylation of the other kinases in the lung epithelial cells. We conclude that the activation of ERK1/2 and PI3K/Akt pathways is required for HNP‐induced IL‐8 release which occurs in a Src‐independent manner in lung epithelial cells, while is Src‐dependent in monocytes. J. Cell. Physiol. 214: 820–827, 2008. © 2007 Wiley‐Liss, Inc.
Microscopic anatomy of pycnogonida: II. Digestive system. III. Excretory system
Authors: Fahrenbach W. H. , Arango Claudia P.
Published: September 2007

The digestive system of several species of sea spiders (Pycnogonida, Arthropoda) was studied by electron microscopy. It is composed of the foregut inside a long proboscis, a midgut and a hindgut. Lips near the three jaws at the tip of the proboscis receive several hundred ductules originating from salivary glands. These previously undetected glands open on the lips, a fluted, projecting ridge at the external hinge line of the jaws, i.e., to the outside of the mouth. This disposition suggests affinities to the chelicerate line. The trigonal esophagus within the proboscis contains a complex, setose filter device, operated by dedicated muscles, that serves to reduce ingested food to subcellular dimensions. The midgut has diverticula into the bases of all legs. Its cells differentiate from the basal layer and contain a bewildering array of secretion droplets, lysosomes and phagosomes. In the absence of a hepatopancreas, the midgut serves both digestive and absorptive functions. The cuticle‐lined hindgut lies in the highly reduced, peg‐like abdomen.

Traditionally, pycnogonids have been claimed to have no excretory organ at all. Such a structure, however, has been located in at least one ammotheid, Nymphopsis spinosissima, in which a simple, but standard, excretory gland has been found in the scape of the chelifore. It consists of an end sac, a straight proximal tubule, a short distal tubule, and a raised nephropore. The end sac is a thin‐walled and polygonal chamber, about 150 μm in cross section, suspended in the hemocoel of the appendage, its edges radially tethered to the cuticle at more than half a dozen locations. This wall consists of a filtration basement membrane, 1–4 μm thick, facing the hemocoel, and internally of a continuous carpet of podocytes and their pedicels. The podocytes, measuring maximally 10 by 15 μm, have complex contents, of which a labyrinthine system of connected intracellular channels stands out. These coated cisternae open into a central vacuole that often rivals the nucleus in size. The design of the organ closely approximates that of the primitive crustacean Hutchinsoniella macracantha. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Antioxidant activity of tryptic digests of hen egg yolk phosvitin
Authors: Xu Xueming , Katayama Shigeru , Mine Yoshinori
Published: September 2007

BACKGROUND: Food protein‐derived peptides with antioxidant activity have great potential for use as natural antioxidants in food products. However, neither the structure–activity relationship nor the antioxidant mechanism of peptides is fully understood. Egg yolk phosvitin has been acknowledged to have strongly antioxidant protein owing to its highly phosphorylated form. In this study the antioxidant activities of tryptic digests of hen egg yolk phosvitin (PPPs), which were prepared by partial dephosphorylation and subsequent hydrolysis by trypsin, were compared with that of intact phosvitin.

RESULTS: Compared with intact phosvitin, PPPs exhibited distinctly stronger capability of inhibiting lipid oxidation in a linoleic acid system and more efficient radical‐scavenging activity on 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radicals. However, the chelating capability of PPPs on iron(II) was weaker than that of intact phosvitin. The strong antioxidant activity of PPPs can be mainly attributed to the amino acid composition rather than to the content of phosphorylserine ligands. Histidine, methionine and tyrosine are the amino acids most likely to be responsible for the strong antioxidant activity of phosvitin peptides.

CONCLUSION: The present study indicated that PPPs could be used in foods as natural antioxidants with strong antioxidant activity. Copyright © 2007 Society of Chemical Industry
Endocrine gland‐derived vascular endothelial growth factor (EG‐VEGF) expression in colorectal cancer
Authors: Nagano Hideki , Goi Takanori , Koneri Kenji , Hirono Yasuo , Katayama Kanji , Yamaguchi Akio
Published: September 2007

Background and Objectives:

Vascular endothelial growth factor (VEGF) is known as an important factor in the growth and metastasis of cancer cells. In 2001, a novel angiogenesis factor, endocrine gland‐derived vascular endothelial growth factor (EG‐VEGF), was cloned. In this study, we investigated the expression of EG‐VEGF in colorectal cancer, the relationship between its expression and clinicopathological factors, and the in vitro activity of EG‐VEGF transfectants.

Methods:

We determined expression levels of EG‐VEGF in 113 advanced colorectal cancers resected in our hospital by quantitative PCR, and compared the expression levels and clinicopathological findings by multivariate analyses.

Results:

The expression of EG‐VEGF mRNA was positive in 31 cancers and negative in 82 cancers. We found that compared with the negative expression of the EG‐VEGF gene, its positive expression was more frequently associated with hematogenous metastasis, and was associated with a poorer survival rate. In addition, EG‐VEGF transfectants showed a higher degree of in vitro tubular formation than control cells.

Conclusions:

We speculate that, in colorectal cancers, the EG‐VEGF gene functions as an important factor in angiogenesis in primary and metastatic lesions, and consider that it is useful as a novel prognostic factor. EG‐VEGF molecule‐targeted therapy has the potential for improving survival rates. J. Surg. Oncol. 2007;96:605–610. © 2007 Wiley‐Liss, Inc.
E‐cadherin expression in early gastric carcinoma and correlation with lymph node metastasis
Authors: Yi Kim Dong , Kyoon Joo Jae , Kyu Park Young , Yeob Ryu Seong , Soo Kim Hyun , Kyun Noh Bok , Hwa Lee Kyung , Hyuk Lee Jae
Published: September 2007

Objective

Abnormal expression of E‐cadherin plays an important role in the differentiation and progression of gastric carcinoma. However, the relationship between molecular changes in E‐cadherin and metastasis in early gastric carcinoma (EGC) is poorly understood.

Materials and Methods

Sixty cases of EGC with or without lymph node metastasis (30 node‐positive cases and 30 node‐negative cases) were investigated to evaluate hypermethylation status using bisulfate‐MSP and immunohistochemistry using antibody against E‐cadherin.

Results

Twenty‐seven (45.0%) of 60 primary EGCs exhibited methylation in the CpG island of E‐cadherin. Abnormal expression of E‐cadherin was significantly correlated with patient age, tumor size, Lauren classification, differentiation, and lymph node metastasis. Using multiple logistic regression analysis, two factors were independent, statistically significant parameters associated with lymph node metastasis: abnormal expression of E‐cadherin (risk ratio, 2.62; 95% confidence interval, 0.917–7.457; P < 0.05) and lymphatic invasion (risk ratio, 8.11; 95% confidence interval, 1.612–40.766; P < 0.05).

Conclusion

Our results suggest that methylation of E‐cadherin is a frequent, early event in gastric carcinoma progression, and is correlated significantly with downregulated E‐cadherin expression. Inactivation of E‐cadherin might be involved in metastasis in EGC and play an important role in microscopic differentiation. J. Surg. Oncol. 2007;96:429–435. © 2007 Wiley‐Liss, Inc.
Tissue preserving hepatectomy by a vessel sealing device
Authors: Tepetes Konstantinos , Christodoulidis Gregory , Spyridakis E. Michael , Chatzitheofilou Constantine
Published: September 2007

Background

The intraoperative blood loss and the biliary leak constitute the major causes of postoperative morbidity following liver resection. We describe a new technique for liver parenchyma transection using the Atlas modification of the ligasure vessel sealing system. The gradual closure of the instrument may cause crushing of the hepatic tissue and heat sealing of the vessels and bile ducts at the same time.

Materials and Methods

Ten cirrhotic patients (group A) underwent minor liver resections due to hepatocellular carcinoma (HCC). In four of these patients a bisegmentectomy was carried out, whereas in the remaining six the resection involved one segment. In addition, twelve patients with localized metastatic liver disease (group B) underwent tissue preserving hepatectomy also. Six of these patients underwent a bisegmentectomy and six had a local resection involving one segment.

Results

The blood loss in the first group varied from 120 to 350 ml, whereas in the second group varied from 80 to 280 ml. No postoperative biliary leakage was mentioned.

Conclusion

This alternative technique of dividing the hepatic parenchyma seems to be simple and efficacious in preventing significant blood loss and bile leak in minor liver resections. J. Surg. Oncol. 2008;97:165–168. © 2007 Wiley‐Liss, Inc.
Saphenous vein graft conduits for insertion of hepatic arterial infusion pumps in patients with abnormal hepatic arterial anatomy
Authors: Yezhelyev Maksym , Osgood Michael , Egnatashvili Vasili , Lumsden Alan , Staley Charles A. , Kooby David A.
Published: September 2007

Background and Objectives:

Hepatic arterial infusion (HAI) chemotherapy offers improved hepatic control for liver metastases from colon cancer. Optimal catheter insertion requires an adequate gastroduodenal artery (GDA). Limited data exists on using saphenous vein grafts (SVG) as conduits when native vasculature is inadequate.

Methods:

All HAI pump insertions from 7/99 to 7/03 requiring SVG conduits (N = 10) were analyzed for arterial anatomy, operative conduct, and outcome.

Results:

From 1988 through 2005, 124 HAI pumps were placed of which 10 received SVG conduits to optimize placement. Mean operative time was 251 ± 50 min and mean blood loss was 230 ± 30 cm3. All were placed with palliative intent. Three patients (30%) had type 1 anatomy with inadequate GDA. Five (50%) had type 3 anatomy with replaced right hepatic artery, one (10%) had a small GDA originating off the right hepatic artery, and one patient (10%) had a trifurcation. Two (20%) pump‐related complications were identified, and only one (10%) was related to vasculature (catheter thrombosis as a result of hepatic arterial stenosis distal to the SVG insertion site).

Conclusions:

Complication rates related to SVG conduits for hepatic arterial infusion pump placement are low. Saphenous vein grafts are acceptable conduits for patients with abnormal hepatic arterial anatomy. J. Surg. Oncol. 2008;97:85–89. © 2007 Wiley‐Liss, Inc.
Overexpression of hERG1 in resected esophageal squamous cell carcinomas: A marker for poor prognosis
Authors: Ding Xiang‐Wu , Luo He‐Sheng , Luo Bing , Xu Dong‐Qiang , Gao Shan
Published: September 2007

Background and objectives

The aim of this study was to evaluate the expression and prognostic roles of human ether à go‐go related gene (hERG1) potassium channels in resected esophageal squamous cell carcinoma.

Methods

Expression of hERG1 protein and mRNA was detected by immunohistochemistry and reverse transcription PCR in resected esophageal squamous cell carcinomas (ESCCs) and non‐cancerous matched tissues, and the correlation was examined between expression of hERG1 protein and clinicopathological factors and prognosis of ESCC patients.

Results

Frequency of positive expression of hERG1 protein was 77.9% (53/68), mRNA was 81.8% (9/11). hERG1 protein and mRNA were negatively expressed in all non‐cancerous matched tissues. There was no significant correlation between hERG1 protein expression and lymph node metastases, depth of penetration, stage, and other clinicopathological factors. Completeness was 92.5% for hERG1‐positive group and 92.0% for hERG1‐negative group. ESCC patients with positive expression of hERG1 protein had a significantly shorter postoperative survival time than those with negative expression (median, 30 vs. 56 months). Survival rates at each time‐point for hERG1‐positive group were lower than that for hERG1‐negative group, and hERG1 was identified as an independent prognostic factor of long‐term survival by multivariate analysis.

Conclusion

In ESCC, hERG1 was aberrantly expressed and correlated with poor prognosis after surgery. J. Surg. Oncol. 2008;97:57–62. © 2007 Wiley‐Liss, Inc.
Loss of Smad4 protein expression and 18qLOH as molecular markers indicating lymph node metastasis in colorectal cancer—a study matched for tumor depth and pathology
Authors: Tanaka Toshiaki , Watanabe Toshiaki , Kazama Yoshihiro , Tanaka Junichiro , Kanazawa Takamitsu , Kazama Shinsuke , Nagawa Hirokazu
Published: September 2007

Purpose

Chromosome 18q21 deletion and Smad4 protein inactivation have been reported as molecular markers predicting unfavorable outcome in colorectal cancers and, in a previous report, we recently revealed that these molecules are closely associated with distant metastasis, which is one of the clinical factors affecting postoperative survival. However, there has been no discussion as to how these molecules influence another clinical factor, namely, lymph node metastasis. In this report, we studied the significance of chromosome 18q deletion and loss of Smad4 protein expression in association with lymph node metastasis.

Method

Forty pairs of colorectal cancer specimens were studied; one group was positive for lymph node metastasis while the other was negative. We examined Smad4 protein expression level and chromosome 18q deletion in the two groups.

Results

Immunohistochemical staining revealed that more cases showed a weaker stain for Smad4 protein in the lymph node positive group compared with the negative group (P = 0.00075). Furthermore, a higher ratio of 18q21 deletion was observed in the lymph node positive group (P = 0.029).

Conclusion

We revealed that chromosome 18q deletion and Smad4 protein inactivation are the essential molecular events in the process of lymph node metastasis. J. Surg. Oncol. 2008;97:69–73. © 2007 Wiley‐Liss, Inc.
Theoretical and numerical analyses of chemical‐dissolution front instability in fluid‐saturated porous rocks
Authors: Zhao Chongbin , Hobbs B. E. , Hornby P. , Ord A. , Peng Shenglin , Liu Liangming
Published: September 2007

The chemical‐dissolution front propagation problem exists ubiquitously in many scientific and engineering fields. To solve this problem, it is necessary to deal with a coupled system between porosity, pore‐fluid pressure and reactive chemical‐species transport in fluid‐saturated porous media. Because there was confusion between the average linear velocity and the Darcy velocity in the previous study, the governing equations and related solutions of the problem are re‐derived to correct this confusion in this paper. Owing to the morphological instability of a chemical‐dissolution front, a numerical procedure, which is a combination of the finite element and finite difference methods, is also proposed to solve this problem. In order to verify the proposed numerical procedure, a set of analytical solutions has been derived for a benchmark problem under a special condition where the ratio of the equilibrium concentration to the solid molar density of the concerned chemical species is very small. Not only can the derived analytical solutions be used to verify any numerical method before it is used to solve this kind of chemical‐dissolution front propagation problem but they can also be used to understand the fundamental mechanisms behind the morphological instability of a chemical‐dissolution front during its propagation within fluid‐saturated porous media. The related numerical examples have demonstrated the usefulness and applicability of the proposed numerical procedure for dealing with the chemical‐dissolution front instability problem within a fluid‐saturated porous medium. Copyright © 2007 John Wiley & Sons, Ltd.
Some fascinating phenomena in electrospinning processes and applications of electrospun nanofibers
Authors: Tan Songting , Huang Xianwei , Wu Bolin
Published: September 2007

Electrospinning has the unique ability to produce ultrathin fibers from a rich variety of materials that include polymers, inorganic or organic compounds and blends. With the enormous increase of research interest in electrospun nanofibers, there is a strong need for a comprehensive review of electrospinning in a systematic fashion. This article presents some fascinating phenomena associated with the remarkable features of nanofibers in electrospinning processes and new progress in applications of electrospun nanofibers. Copyright © 2007 Society of Chemical Industry
Development, characterisation and 1000 Suns outdoor tests of GaAs monolithic interconnected module (MIM) receivers
Authors: Loeckenhoff R. , Dimroth F. , Oliva E. , Ohm A. , Wilde J. , Faiman David , Biryukov Sergey , Melnichak Vladimir , Kabalo Shlomo , Bokobza Dov , Bett A. W.
Published: September 2007

Monolithic interconnected modules (MIMs) are large area, high voltage PV devices which perform well at very high light intensities. They are therefore well suited for the assembly of dense array receivers. The latter can be employed in solar concentrator systems such as parabolic dishes at a concentration ratio of 1000 Suns or more. This paper reports on progress in the development and testing of GaAs MIMs and of water‐cooled dense array receivers assembled from MIMs. The MIMs are electrically protected by integrated bypass diodes and, under indoor laboratory tests, reach an efficiency of 20·0% at 1000 Suns and 22·9% at 200 Suns. Several dense array receivers have been assembled, one of which was tested outdoors at 1‐Sun and at concentration ratios of several hundred Suns and up to slightly above 1000 Suns using thePETALsolar dish facility in Sede Boqer, Israel. In addition to I–V curve measurements, the high‐concentration tests included measurements that quantified the light intensity distribution over the dense array. Deformations in some of the I–V plots were observed for intensity distributions that departed substantially from perfect uniformity. The shapes of these plots were successfully reproduced by an electronic network simulation of the inhomogeneously illuminated receiver. 1‐Sun I–V curve measurements and visual inspections performed before and after exposure of the module to concentrated sunlight revealed no indications of degradation. Copyright © 2007 John Wiley & Sons, Ltd.
Conducting and magnetic behaviors of monodispersed iron oxide/polypyrrole nanocomposites synthesized by in situ chemical oxidative polymerization
Authors: Wu Tzong‐Ming , Yen Shiang‐Jie , Chen Erh‐Chiang , Sung Ti‐Wen , Chiang Ray‐Kuang
Published: September 2007

This study describes the preparation of nanocomposites fabricated from monodispersed iron oxide (Fe3O4) and polypyrrole (PPy) by in situ chemical oxidative polymerization. The monodispersed 4 nm Fe3O4 nanoparticles which served as cores were synthesized using the thermal decomposition of a mixture of Iron (III) acetylacetonate and oleic acid in the presence of high boiling point solvents. The resulting nanoparticles were further dispersed in an aqueous solution with anionic surfactant sodium bis(2‐ethylhexyl) sulfosuccinate to form micelle/Fe3O4 spherical templates that avoid the aggregation of Fe3O4 nanoparticles during the further preparation of the nanocomposites. The Fe3O4/PPy nanocomposites were then synthesized via in situ chemical oxidative polymerization on the surface of the spherical templates. Both field‐emission scanning electron microscopy (FESEM) and high‐resolution transmission electron microscopy (HRTEM) images indicate that the resulting Fe3O4 nanoparticles are close to spherical dots with a particle size of about 4 nm and a standard deviation of less than 5% (4 ± 0.2 nm). Structural and morphological analysis using FESEM and HRTEM showed that the fabricated Fe3O4/PPy nanocomposites are core (Fe3O4)‐shell (PPy) structures. Morphology of the nanocomposites shows a remarkable change from spherical to tube‐like structures as the content of monodispersed Fe3O4 nanoparticles increases from 9% up to 24 wt %. The conductivities of these Fe3O4/PPy nanocomposites are about six times higher than those of PPy without Fe3O4. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4647–4655, 2007
Preliminary evaluation of sulfonated poly(ether ether ketone)/monoethanolamine/adipic acid composite membranes for direct methanol fuel cell applications
Authors: Zhong Shuangling , Cui Xuejun , Cai Hongli , Fu Tiezhu , Na Hui
Published: September 2007

A series of sulfonated poly(ether ether ketone)/monoethanolamine/adipic acid (SPEEK/MEA/AA) composite membranes are prepared and investigated to assess their possibility as proton exchange membranes in direct methanol fuel cells (DMFCs). A preliminary evaluation shows that introducing MEA and AA into SPEEK matrix decreases the thermal stability of membrane. However, the degradation temperatures are still above 260 °C, satisfying the requirement for fuel cell operation. Compared with the pure SPEEK membrane, the composite membranes exhibit not only lower water uptake and swelling ratios but also better mechanical property and oxidative stability. Noticeably, the methanol diffusion coefficient of the composite membranes decrease significantly from 3.15 × 10−6 to 0.76 × 10−6 cm2/s with increasing MEA and AA content, accompanied by only a small sacrifice in proton conductivity. Although both the methanol diffusion coefficient and the proton conductivity of composite membranes are lower than those of pure SPEEK and Nafion® 117 membranes, their selectivity (conductivity/methanol diffusion coefficient) are higher. In addition, the composite membranes show excellent stability in aqueous methanol solution. The good thermal and chemical stability, low swelling ratio, excellent mechanical property, low methanol diffusion coefficient, and high selectivity make the use of these composite membranes in DMFCs quite attractive. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2871–2879, 2007
A photon transmission study for film formation from poly(vinyl acetate) latex particles with different molecular weights
Authors: Arda Ertan , Kara Selim , Pekcan Önder
Published: September 2007

The photon transmission technique was used to monitor the temperature evolution of film formation from poly(vinyl acetate) (PVAc) latex particles with two different molecular weights. Two sets of latex films were prepared below the glass transition temperature (Tg) of PVAc, which are named as low (LM) and high molecular weight (HM) films. These films were annealed at elevated temperatures above the Tg of PVAc for various time intervals. It is observed that transmitted photon intensity (Itr) from these films increased as the annealing temperature was increased. Onset temperatures (TH) at given times (τH) for starting the optical clarity of LM and HM films were measured and used to calculate the healing activation energies (ΔH) for the PVAc minor chains, and found to be as 28.1 kcal/mol and 27.7 kcal/mol, respectively. The increase in the transmitted photon intensity, Itr above TH was attributed to the increase in the number of disappeared interfaces between the deformed latex particles. Prager–Tirrell (PT) model was employed to interpret the increase in the crossing density of chains at the junction surfaces. The interdiffusion (backbone) activation energies (ΔE) were measured and found to be 177.5 kcal/mol and 210.7 kcal/mol for a diffusing PVAc chains across the junction surface of LM and HM latex films, respectively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2918–2925, 2007
Vertical defects in heavily Mg‐doped Al0.69Ga0.31N
Authors: Wu Y. , Moe C. G. , Keller S. , DenBaars S. P. , Speck J. S.
Published: September 2007

The microstructure of p‐type Al0.69Ga0.31N with high Mg‐doping was studied by conventional transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). Spike‐like domains were observed with an average diameter of ∼10 nm, height of ∼400 nm and density of 2.2 × 1011/cm2. These long and narrow domains nucleated about 200 nm above the Mg‐doping boundary and resembled ordinary inversion domains induced by Mg‐doping. However, the energy dispersive X‐ray spectroscopy line‐scan results provided unambiguous evidence that the domains were Ga‐rich. The lateral composition segregation between the domains and surrounded matrix was further confirmed by high angular dark field images in STEM. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles study of the electronic structure and the associated magnetism of carbon‐doped TiO2
Authors: Li Q. K. , Wang B. , Zheng Y. , Wang Q. , Wang H.
Published: September 2007

Based on first‐principles calculations, the electronic structure and the associated magnetism of carbon‐doped rutile TiO2 have been investigated in the frame of the generalized gradient approximation (GGA). We find that the carbon substitutional oxygen ions can induce a magnetic moment of about 2.0µB/C, but the carbon substitutional titanium cannot provide any magnetism. Graphics of the spin density show that the magnetism is from the structure distortion around the carbon substitutional oxygen ions in the (110) plane of primitive TiO2. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical calculation of overlap and kinetic integrals in prolate spheroidal coordinates
Authors: Romanowski Zbigniew
Published: September 2007

The efficient algorithm calculating the overlap and the kinetic integrals for the numerical atomic orbitals is presented. The described algorithm exploits the properties of the prolate spheroidal coordinates. The overlap and the kinetic integrals in ℝ3 are reduced to the integrals over the rectangular domain in ℝ2, what substantially reduces the complexity of the problem. We prove that the integrand over the rectangular domain is continuous and does not have any slope singularities. For calculation of the integral over the rectangle any adaptive algorithm can be applied. The exemplary results were obtained by application of the adaptive Gauss quadrature. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
The cutoff phenomenon for randomized riffle shuffles
Authors: Chen Guan‐Yu , Saloff‐Coste Laurent
Published: September 2007

We study the cutoff phenomenon for generalized riffle shuffles where, at each step, the deck of cards is cut into a random number of packs of multinomial sizes which are then riffled together. © 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2008
Novel Biocatalysts Based on S‐Layer Self‐Assembly of Geobacillus Stearothermophilus NRS 2004/3a: A Nanobiotechnological Approach
Authors: Schäffer Christina , Novotny René , Küpcü Seta , Zayni Sonja , Scheberl Andrea , Friedmann Jacqueline , Sleytr Uwe B. , Messner Paul
Published: September 2007

The crystalline cell‐surface (S) layer sgsE of Geobacillus stearothermophilus NRS 2004/3a represents a natural protein self‐assembly system with nanometer‐scale periodicity that is evaluated as a combined carrier/patterning element for the conception of novel types of biocatalyst aiming at the controllable display of biocatalytic epitopes, storage stability, and reuse. The glucose‐1‐phosphate thymidylyltransferase RmlA is used as a model enzyme and chimeric proteins are constructed by translational fusion of rmlA to the C‐terminus of truncated forms of sgsE (rSgsE 131−903, rSgsE331−903) and used for the construction of three principal types of biocatalysts: soluble (monomeric), self‐assembled in aqueous solution, and recrystallized on negatively charged liposomes. Enzyme activity of the biocatalysts reaches up to 100 % compared to sole RmlA cloned from the same bacterium. The S‐layer portion of the biocatalysts confers significantly improved shelf life to the fused enzyme without loss of activity over more than three months, and also enables biocatalyst recycling. These nanopatterned composites may open up new functional concepts for biocatalytic applications in nanobiotechnology.
Genetics and breeding of sunflower
Authors: Fick G. N.
Published: September 2007

Considerable progress has been made to improve sunflower through breeding and genetics programs. Continued improvement appears feasible. Present information suggests that large numbers of new lines and hybrids are available that are superior in yield potential, disease and insect tolerance, agronomic traits, and/or oil quantity and quality characteristics.
Parallel analysis of tetramerization domain mutants of the human p53 protein using PCR colonies
Authors: Merritt Joshua , Roberts Kim G. , Butz James A. , Edwards Jeremy S.
Published: September 2007

A highly-parallel yeast functional assay, capable of screening approximately 100–1,000 mutants in parallel and designed to screen the activity of transcription activator proteins, was utilized to functionally characterize tetramerization domain mutants of the human p53 transcription factor and tumor suppressor protein. A library containing each of the 19 possible single amino acid substitutions (57 mutants) at three positions in the tetramerization domain of the human p53 protein, was functionally screened in Saccharomyces cerevisiae. Amino acids Leu330 and Ile332, whose side chains form a portion of a hydrophobic pocket that stabilizes the active p53 tetramer, were found to tolerate most hydrophobic amino acid substitutions while hydrophilic substitutions resulted in the inactivation of the protein. Amino acid Gln331 tolerated essentially all mutations. Importantly, highly parallel mutagenesis and cloning techniques were utilized which, in conjunction with recently reported highly parallel DNA sequencing methods, would be capable of increasing throughput an additional 2–3 orders of magnitude.
Identification and Validation of Proteinase 3 and Latent Matrix-Metalloproteinase 9 as Potential Biomarkers for Chronic Lung Transplant Rejection
Authors: Zhang Yan , Wendt Christine H. , Hertz Marshall I. , Nelsestuen Gary L.
Published: September 2007

Introduction

This study examined potential biomarkers for the diagnosis and early detection of chronic allograft rejection after lung transplantation.

Methods

Protein ratios in pooled samples of bronchoalveolar lavage fluid (BALF) from lung transplant recipients at different stages of pre- and postchronic rejection were determined by iTRAQ labeling and mass spectrometry. The potential biomarkers were validated using enzyme-linked immunosorbent assay (ELISA) assay.

Results

Two hundred sixty-five proteins were identified, about two thirds of which showed more than a twofold difference between a pooled control sample (individuals who did not develop chronic rejection in 100 months) and a pooled sample from those with chronic rejection. Proteinase 3 (PR-3) and matrix metalloproteinase 9 (MMP-9) were validated by ELISA assay of 124 individual samples. PR-3 and the latent form of MMP-9 (proMMP9) both demonstrated a specificity of 92% with sensitivities of 76% and 82%, respectively, for disease diagnosis; both were also predictors of developing chronic rejection up to 15 months before diagnosis. While immunoglobulin M (IgM) was upregulated in the pooled samples, individual sample analysis revealed that this arose from outlier values.

Conclusions

iTRAQ can be used to detect a large number of proteins in pooled samples for the discovery of potential biomarkers, but the findings must be validated with technology capable of distinguishing broadly based changes from outcomes as a result of a few extreme cases. The proteins identified in this study expanded the panel of potential biomarkers for the diagnosis and prediction of chronic rejection and provided additional insight into the mechanism of the disease.
Regularity results for degenerate elliptic systems
Authors: Pingen Michael
Published: September 2007

We prove regularity results for certain degenerate quasilinear elliptic systems with coefficients which depend on two different weights. By using Sobolev- and Poincaré inequalities due to Chanillo and Wheeden [S. Chanillo, R.L. Wheeden, Weighted Poincaré and Sobolev inequalities and estimates for weighted Peano maximal functions, Amer. J. Math. 107 (1985) 1191–1226; S. Chanillo, R.L. Wheeden, Harnack's inequality and mean-value inequalities for solutions of degenerate elliptic equations, Comm. Partial Differential Equations 11 (1986) 1111–1134] we derive a new weak Harnack inequality and adapt an idea due to L. Caffarelli [L.A. Caffarelli, Regularity theorems for weak solutions of some nonlinear systems, Comm. Pure Appl. Math. 35 (1982) 833–838] to prove a priori estimates for bounded weak solutions. For example we show that every bounded weak solution of the system

−D_{\alpha }(a^{\alpha \beta }(x,u,\mathrm{∇}u)D_{\beta }u^{i}) = 0

with

|x|^{2}|\xi |^{2}⩽a^{\alpha \beta }\xi _{\alpha }\xi _{\beta }⩽|x|^{\tau }|\xi |^{2}

,

|x| < 1

,

\tau \in (1,2)

is Hölder continuous. Furthermore we derive a Liouville theorem for entire solutions of the above systems.

Nous prouvons des résultats de régularité pour certains systèmes elliptiques quasi linéaires dégénérés avec des coefficients dépendant de deux poids différents. En employant des inégalités de Sobolev- et Poincaré dues à Chanillo et Wheeden [S. Chanillo, R.L. Wheeden, Weighted Poincaré and Sobolev inequalities and estimates for weighted Peano maximal functions, Amer. J. Math. 107 (1985) 1191–1226 ; S. Chanillo, R.L. Wheeden, Harnack's inequality and mean-value inequalities for solutions of degenerate elliptic equations, Comm. Partial Differential Equations 11 (1986) 1111–1134] nous déduisons une nouvelle inégalité de Harnack et adaptons une idée due à L. Caffarelli [L.A. Caffarelli, Regularity theorems for weak solutions of some nonlinear systems, Comm. Pure Appl. Math. 35 (1982) 833–838] pour prouver des évaluations a priori pour des solutions limitées et faibles. Par exemple, chaque solution limitée et faible du système

−D_{\alpha }(a^{\alpha \beta }(x,u,\mathrm{∇}u)D_{\beta }u^{i}) = 0

avec

|x|^{2}|\xi |^{2}⩽a^{\alpha \beta }\xi _{\alpha }\xi _{\beta }⩽|x|^{\tau }|\xi |^{2}

,

|x| < 1

,

\tau \in (1,2)

est continue selon Hölder. De plus, nous déduisons un théorème de Liouville pour les solutions entières des systèmes ci-dessus.
Strong solutions for a compressible fluid model of Korteweg type
Authors: Kotschote Matthias
Published: September 2007

We prove existence and uniqueness of local strong solutions for an isothermal model of capillary compressible fluids derived by J.E. Dunn and J. Serrin (1985). This nonlinear problem is approached by proving maximal regularity for a related linear problem in order to formulate a fixed point equation, which is solved by the contraction mapping principle. Localising the linear problem leads to model problems in full and half space, which are treated by Dore–Venni Theory, real interpolation and

\mathcal{H}^{\infty }

-calculus. For these steps, it is decisive to find conditions on the inhomogeneities that are necessary and sufficient.

Nous prouvons l'existence et l'unicité de fortes solutions locales pour un modèle de fluides compressibles isothermes avec capillarité, dérivé par J.E. Dunn et J. Serrin (1985). L'idée de la démonstration consiste à montrer la régularité maximale d'un problème linéaire apparenté, afin de formuler un problème de point fixe, résolu par la suite par le principe de la contraction. Le problème linéaire est transféré par le principe de la localisation aux problèmes de modèle correspondants sur l'espace entier et sur le demi-espace. Ceux-là peuvent être traités à l'aide de la théorie de Dore–Venni, de l'interpolation réelle et du calcul des

\mathcal{H}^{\infty }

. Pour ces étapes, il est essentiel de trouver les conditions nécessaires et suffisantes pour les inhomogénéités.
Nonlinear diffusion from a delocalized source: affine self-similarity, time reversal, & nonradial focusing geometries
Authors: Denzler Jochen , McCann Robert J.
Published: September 2007

A family of explicit solutions is described, to the porous medium equation in its full range of nonlinearities (plus some analogous fourth-order diffusions), in which the pressure is given by a quadratic function of space at each instant in time. These include spreading solutions whose source is concentrated on any conic region of dimension lower than the ambient space, and solutions which focus at conic regions. The singular limiting distributions are affine projections of Barenblatt type solutions (with arbitrary signature) onto lower dimensional subspaces. All affine images of Barenblatt solutions form an invariant space on which the dynamics can be integrated explicitly. A time-reversal symmetry is revealed for the pressure equation which transforms spreading solutions to focusing solutions, and vice-versa. This yields new information about the long and short time asymptotics of finite-mass solutions, about the instability of focusing, and about singularity geometry.

On décrit une famille de solutions explicites pour l'équation des milieux poreux pour toute l'échelle des nonlinéarités (ainsi que pour d'autres équations de diffusion analogues de quatrième degré). Pour ces solutions, la pression à chaque instant est une fonction quadratique en

\boldsymbol x

. Certaines de ces solutions sont diffusées à partir d'une source concentrée sur un domaine conique arbitraire de dimension inférieure à celle de l'espace ambient ; d'autres se focalisent sur des régions coniques. Pour les solutions focalisantes, on obtient à la limite une distribution singulière qui est une projection affine d'une solution de type Barenblatt (à signature arbitraire) sur un espace de dimension inférieure. L'ensemble des images affines des solutions de type Barenblatt est un espace invariant, sur lequel la dynamique peut s'intégrer explicitement. Par un changement de variables qui inverse le sens du temps, on arrive à transformer une solution diffusive en une solution focalisante. Ceci donne de nouvelles informations sur l'asymptotique en temps court et long pour des solutions de masse finie, sur l'instabilité des solutions focalisantes, ainsi que sur la géométrie des singularités.
Establishment and characterisation of two novel breast cancer cell lines
Authors: Bagadi Sarangadhara Appala Raju , Kaur Jatinder , Ralhan Ranju
Published: September 2007

Two novel oestrogen receptor (ER) negative breast cancer cell lines, BCa‐11 (familial) and BCa‐15 (sporadic) were successfully established from primary tumours. Characterisation of these cell lines showed expression of epithelial specific antigen and cytokeratins confirming their epithelial lineage. Analysis of ultrastructure and anchorage independent growth confirmed the epithelial nature and transformed phenotype of these cells. Both cell lines showed loss of pRb, Dab2 and ERα and elevated levels of proliferation marker Ki67. In addition, BCa‐11 cells showed loss of HOXA5, tumour suppressor genes p16INK4A and RARβ as well as overexpression of CyclinD1. Elevation of DNMT1 and DNMT3B transcript levels, promoter hypermethylation of RASSF1A, RARβ2, and HOXA5 further support their neoplastic origin. In conclusion, the two ERα negative breast cancer cell lines established herein have certain useful characteristics that may make them valuable for understanding the mechanism of oestrogen receptor negative breast tumours and testing new drugs.