bluuebunny/crossref_metadata_2025 huggingface dataset:
Spherulocytes in the echinoderm Holothuria glaberrima and their involvement in intestinal regeneration
Authors: García‐Arrarás José E. , Schenk Christian , Rodrígues‐Ramírez Roxanna , Torres Irma I. , Valentín Griselle , Candelaria Ann Ginette
Published: October 2006

The holothuroid echinoderm Holothuria glaberrima can regenerate its intestine after a process of evisceration. Spherule‐containing cells, the spherulocytes, appear to be associated with intestinal regeneration. We have used histochemistry and immunocytochemistry to characterize these cells and their role in the regeneration process. Spherulocytes are 10–20 μm in diameter with an acrocentric nucleus and spherule‐like structures within their cytoplasm. They are found in the connective tissue of the intestine and mesentery of noneviscerated and regenerating animals. During the second week of regeneration, the number of spherulocytes in the regenerating intestine increases and a dramatic change in their morphology occurs. Together with the morphological change, the immunohistochemical labeling of the cells also changes; the antibodies not only recognize the spherule structures but also label the cellular cytoplasm in a more homogeneous pattern. Moreover, immunohistochemical labeling also appears to be dispersed within the extracellular matrix, suggesting that the cells are liberating their vesicular contents. Spherulocytes are found in other tissues of H. glaberrima, always associated with the connective tissue component. Our data strongly suggest that spherulocytes are involved in intestinal regeneration but their specific role remains undetermined. In summary, our data expand our knowledge of the cellular events associated with regeneration processes in echinoderms and provide for comparisons with similar processes in vertebrates. Developmental Dynamics 235:3259–3267, 2006. © 2006 Wiley‐Liss, Inc.
Three types of cilia including a novel 9+4 axoneme on the notochordal plate of the rabbit embryo
Authors: Feistel Kerstin , Blum Martin
Published: October 2006

Motile monocilia play a pivotal role in left‐right axis determination in mouse and zebrafish embryos. Cilia with 9+0 axonemes localize to the distal indentation of the mouse egg cylinder (“node”), while Kupffer's vesicle cilia in zebrafish show 9+2 arrangements. Here we studied cilia in a prototype mammalian embryo, the rabbit, which develops via a flat blastodisc. Transcription of ciliary marker genes Foxj1, Rfx3, lrd, polaris, and Kif3a initiated in Hensen's node and persisted in the nascent notochord. Cilia emerged on cells leaving Hensen's node anteriorly to form the notochordal plate. Cilia lengthened to about 5 μm and polarized from an initially central position to the posterior pole of cells. Electron‐microscopic analysis revealed 9+0 and 9+2 cilia and a novel 9+4 axoneme intermingled in a salt‐and‐pepper‐like fashion. Our data suggest that despite a highly conserved ciliogenic program, which initiates in the organizer, axonemal structures may vary widely within the vertebrates. Developmental Dynamics 235:3348–3358, 2006. © 2006 Wiley‐Liss, Inc.
The initial fetal human retinal vasculature develops by vasculogenesis
Authors: McLeod D. Scott , Hasegawa Takuya , Prow Tarl , Merges Carol , Lutty Gerard
Published: October 2006

There is increasing evidence that the hemangioblast, a common progenitor for hematopoietic cells and endothelial cells, participates in embryonic and extra‐embryonic vasculogenesis in some organs. Whether resident angioblasts or endothelial progenitor cells (EPCs) contribute to human retinal vasculogenesis is still a matter of controversy. To address this controversy, fetal human retinas of 6–23 weeks gestation (WG) were examined using immunohistochemistry and a panel of antibodies against endothelial cell markers (CD34, CD31), a marker for retinal angioblasts and endothelium (CD39/ecto‐ADPase), and a marker for precursors and hemangioblasts (CXCR4). Confocal microscopic spectral analysis and double labeling with Ki67 was used to identify the proliferating cell types. In the inner neuroblastic layer of the 6–8 WG retina and in the putative ganglion cell layer in avascular regions of older eyes (14 WG–20 WG), scattered CD39+ angioblasts were well in advance of forming vasculature. There was a layer of CXCR4+ cells in the inner retina that was reduced in size with development. As blood vessels formed, CD39+ cells were always well in advance of the vascular front and they expressed CXCR4. This demonstrates that a pool of resident angioblasts express CD39 and CXCR4 as they differentiate and participate in vasculogenesis in the fetal human. They retain expression of CD39 as endothelial cells in the newly formed retinal vasculature but they down‐regulate CXCR4 expression. Developmental Dynamics 235:3336–3347, 2006. © 2006 Wiley‐Liss, Inc.
Contribution to the Reactivity of N,N′‐Diaryl‐1,4‐diazabutadienes Aryl–N=CH–CH=N–Aryl (Aryl = 2,6‐Dimethylphenyl; 2,4,6‐Trimethylphenyl) Towards Boron Trichloride
Authors: Weber Lothar , Förster Jan , Stammler Hans‐Georg , Neumann Beate
Published: October 2006

The reaction of Aryl–N=CH–CH=N–Aryl (3a: Aryl = 2,6‐Me2C6H3; 3b: Aryl = 2,4,6‐Me3C6H2) with 2 equiv. BCl3 in a toluene/hexane mixture at –50 °C led to an inseparable mixture of borolium salts [Aryl–Na=CH–CH=N(Aryl)BCl2(Na–B)]+BCl4– (4a: Aryl = 2,6‐Me2C6H3; 9a: Aryl = 2,4,6‐Me3C6H2) and [Aryl–Na=CH–C(Cl)=N(Aryl)BCl2(Na–B)]+BCl4– (4b: Aryl = 2,6‐Me2C6H3; 9b: Aryl = 2,4,6‐Me3C6H2) and the bicyclic species [HCa=N(Aryl)BCl2N(Aryl)–Cb=(Ca–Cb)]2 (5: Aryl = 2,6‐Me2C6H3; 10: Aryl = 2,4,6‐Me3C6H2). Sodium amalgam reduction of borolium salts 4a,b and 9a,b afforded inseparable mixtures of the diazaboroles 2,6‐Me2C6H3NaCH=CR–Nb(2,6‐Me2C6H3)BCl(Na–B) (1: R = H; 6: R = Cl) and 2,4,6‐Me3C6H2NaCH=CR–Nb(2,4,6‐Me3C6H2)BCl(Na–B) (2: R = H; 11: R = Cl). In order to obtain pure 1 and 2, diazabutadienes 3a and 3b were slowly combined with 2 equiv. BCl3 in the same solvents at –78 °C. The acyclic adducts Cl3BN(Aryl)=CH–CH=N(Aryl)BCl3 (7a: Aryl = 2,6‐Me2C6H3; 7b: Aryl = 2,4,6‐Me3C6H2) were reduced with sodium amalgam to furnish the aminoboranes Cl2BN(Aryl)CH=CH–N(Aryl)BCl2 (8: Aryl = 2,6‐Me2C6H3; 12: Aryl = 2,4,6‐Me3C6H2). Stirring solutions of 8 and 12 in the presence of CaH2 cleanly gave the diazaboroles 1 and 2, respectively. The novel compounds were characterized by elemental analyses and 1H‐, 11B‐, 13C NMR and mass spectra. The molecular structures of 1, 4a, 5 and 8 were elucidated by single X‐ray diffraction analyses. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
“Inhibition” of the Enzyme Model TpPh,MeZn–OH by Diketo Compounds
Authors: Tekeste Teame , Vahrenkamp Heinrich
Published: October 2006

In order to gain a structural understanding of zinc enzyme inhibition, the model complex TpPh,MeZn–OH was treated with various diketo compounds. α‐Keto carboxylic acids were attached to the zinc ion as anionic O,O‐chelate ligands, of which benzoylformate was oxidatively decarboxylated in air to form the benzoate complex. Two functionalized β‐diketones did not use their functionality in forming the β‐diketonate complexes. Of the α‐diketones, 2,3‐pentanedione formed the α‐keto enolate complex, while 1‐phenyl‐1,2‐propanedione underwent oxidative C–C coupling resulting in a red dinuclear bis(α‐keto enolato) complex. Of the diaryl‐α‐diketones, benzil did not react, but pyridil underwent hydrolytic cleavage to pyridine‐2‐carbaldehyde and picolinate, of which the latter was bound to the zinc ion as an N,O‐chelate ligand.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Recoverable Homogeneous Palladium(0) Catalyst for Cross‐Coupling Reactions of Arenediazonium Salts with Potassium Organotrifluoroborates: Detection of Catalytic Intermediates by Electrospray Ionization Mass Spectrometry
Authors: Masllorens Judit , González Iván , Roglans Anna
Published: October 2006

Fifteen‐membered triolefinic macrocyclic palladium(0) complex 1, (E,E,E)‐1‐ferrocenylsulfonyl‐6,11‐bis[(4‐methylphenyl)sulfonyl]‐1,6,11‐triazacyclopentadeca‐3,8,13‐trienepalladium(0), is an active and recoverable catalyst for Suzuki–Miyaura cross‐couplings between arenediazonium salts and potassium organotrifluoroborates. The reactions were performed under aerobic conditions at room temperature and without added base. Use of electrospray ionization mass spectrometry (ESI‐MS) allowed the direct detection and identification of several intermediates, which furthers the study of the mechanistic aspects of the Suzuki–Miyaura reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Restoring nature in mining areas of the Silesian Upland (Poland)
Authors: Pełka‐Gościniak Jolanta
Published: October 2006

The Silesian Upland is one of the most degraded areas in Poland owing to the long‐lasting influence of mining and metallurgy. Mining influences every component of the environment in significant and diverse ways. But even in such a devastated terrain there is evidence of the proper management of post‐mining areas and natural self‐restoration, which paradoxically, owing to mining, appear in the most intensively used economic areas. Copyright © 2006 John Wiley & Sons, Ltd.
The Effect of NaCl in the Cathode Air Stream on PEMFC Performance
Authors: Mikkola M. S. , Rockward T. , Uribe F. A. , Pivovar B. S.
Published: October 2006

In this contribution, the effects of sodium chloride in the cathode side air stream of a polymer electrolyte membrane fuel cell were studied, since it is present in the atmosphere in many fuel cell operating environments, especially at coastal regions and on roads where NaCl is used as a deicer. The effect on PEMFC performance was investigated by injecting NaCl solution into the cathode side air stream of an operating fuel cell. The most significant effect of NaCl under test conditions is the replacement of H+ by Na+ in the ionomer, lowering performance by reducing proton conductivity. In addition, NaCl was found to absorb into the graphite components, making them a potential long‐term NaCl source after the initial exposure. In contrast to expectations, chloride ions did not appear to effect performance of the cell and the overall magnitude of the effects due to NaCl introduction were smaller than expected.
Common fragile site FRA11G and rare fragile site FRA11B at 11q23.3 encompass distinct genomic regions
Authors: Fechter Anne , Buettel Isabel , Kuehnel Elisabeth , Savelyeva Larissa , Schwab Manfred
Published: October 2006

Fragile sites are specific genomic loci that are particularly prone to chromosomal breakage. Based on their incidence in the human population, they are divided into rare fragile sites occurring in less than 5% of all individuals and common fragile sites being a constitutional feature of the genome of probably all individuals. In this study, cloning of unstable DNA sequences, which have been previously genetically tagged with a marker gene, was the basis for defining the genomic localization of the common fragile site FRA11G at 11q23.3. Mapping of the fragile site with six‐color fluorescence in situ hybridization (FISH) resulted in the precise genomic localization of FRA11G to a 4.5 Mb region. The chromosomal subband 11q23.3 harbors both the common fragile site FRA11G and the rare fragile site FRA11B. Here, we show that FRA11G maps 0.8 Mb proximal to the genomic region previously defined to be affected by expression of FRA11B; thus, the common and the rare fragile sites at 11q23.3 encompass distinct genomic regions. The region of FRA11G is known to be involved in somatic and germline recurrent aberrations, and it is conceivable that genetic damage resulting from this fragile site might contribute to clinical phenotypes. © 2006 Wiley‐Liss, Inc.
Chemical fragments in real space: Definitions, properties, and energetic decompositions
Authors: Pendás A. Martín , Blanco M. A. , Francisco E.
Published: October 2006

The physical and chemical meaning of real space molecular fragments resulting from arbitrary partitions of the density is reviewed under a common unifying formalism. Both fuzzy (interpenetrating) and non‐fuzzy (exhaustive) decompositions are treated on an equal basis. Density decompositions are consistently generalized to compatible density matrix partitions by using Li and Parr's ideas (Li and Parr J Chem Phys 1986, 84, 1704), and these are carried onto an energy partition. It is argued that the merits of a given decomposition should be judged against both the charge and the energetic image it provides. Atomic partitions are used to show how the interacting quantum atoms approach (IQA) allows us to cope with the most important energy cancellations of quantum chemistry. Binding results from a trade‐off between atomic (or fragment) energy deformations with respect to a reference and interatomic (interfragment) interactions. Deformation energies are divided into charge transfer and redistribution terms and their relative roles are analyzed. A number of systems are compared against the fuzziness of different density decompositions. The results consistently show that fuzzy partitions tend to give low atomic net charges and enhanced covalency, while exhaustive partitions generate larger net charges and smaller covalencies, across a wide range of bonding regimes. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2007
A survey of recent developments in ab initio valence bond theory
Authors: Hiberty Philippe C. , Shaik Sason
Published: October 2006

Starting from the 1980s and onwards, Valence Bond theory has been enjoying renaissance that is characterized by the development of a growing number of ab initio methods, and by many applications to chemical reactivity and to the central paradigms of chemistry. Owing the increase of computational power of modern computers and to significant advances in the methodology, valence bond theory begins to offer a sound and attractive alternative to Molecular Orbital theory. This review aims at summarizing the most important developments of ab initio valence bond methods during the last two or three decades, and is primarily devoted to a description of what the various methods can actually achieve within their specific scopes and limitations. Key available softwares are surveyed. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2007
Hamilton cycle decomposition of 6‐regular circulants of odd order
Authors: Dean Matthew
Published: October 2006

The circulant G = C(n,S), where $S\subseteq Z_n\setminus\{0\}$, is the graph with vertex set Zn and edge set $E(G)= \{\{x,x+s\}|x \in Z_n,s \in S\}$. It is shown that for n odd, every 6‐regular connected circulant C(n, S) is decomposable into Hamilton cycles. © 2006 Wiley Periodicals, Inc. J Combin Designs
Asymmetric ERM activation at the Schwann cell process tip is required in Axon‐Associated motility
Authors: Gatto Cheryl L. , Walker Barbara J. , Lambert Stephen
Published: October 2006

Axon‐associated Schwann cell (SC) motility and process dynamics are crucial in the development and regeneration of the peripheral nervous system (PNS). The bipolar morphology of SCs represents an unexplored conundrum in terms of directed motility. Using fluorescence time‐lapse microscopy of transfected SCs within myelinating dorsal root ganglion (DRG) explants, we demonstrate cycling of SCs between bipolar and highly motile, unipolar morphologies as a result of asymmetric process retraction and extension. Unipolar SC motility appears nucleotaxic in nature, similar to the movement of neurons on radial glia during cortical development. We also show that asymmetric process retraction is associated with the activation of ERM (ezrin/radixin/moesin) proteins and subsequent recruitment of ezrin‐binding phospho‐protein 50 kDa (EBP50) at the retracting process tip. This activation occurs in response to localized synthesis of phosphatidylinositol (4,5)‐bisphosphate (PIP2) at this site. Finally, we demonstrate that the activation of ERM proteins at the SC process tip is essential for motility and the maintenance of SC polarity, as ERM disruption yields a dysfunctional, multi‐polar cell. These results demonstrate that specializations at the tips of SC processes regulate their dynamics, which in turn is associated with directed motility in these cells. J. Cell. Physiol. 210: 122–132, 2007. © 2006 Wiley‐Liss, Inc.
Molecular determinants of FGF‐21 activity—synergy and cross‐talk with PPARγ signaling
Authors: Moyers Julie S. , Shiyanova Tatiyana L. , Mehrbod Farrokh , Dunbar James D. , Noblitt Timothy W. , Otto Keith A. , Reifel‐Miller Anne , Kharitonenkov Alexei
Published: October 2006

Fibroblast growth factor (FGF)‐21 is a novel regulator of insulin‐independent glucose transport in 3T3‐L1 adipocytes and has glucose and triglyceride lowering effects in rodent models of diabetes. The precise mechanisms whereby FGF‐21 regulates metabolism remain to be determined. Here we describe the early signaling events triggered by FGF‐21 treatment of 3T3‐L1 adipocytes and reveal a functional interplay between FGF‐21 and peroxisome proliferator‐activated receptor gamma (PPARγ) pathways that leads to a marked stimulation of glucose transport. While the early actions of FGF‐21 on 3T3‐L1 adipocytes involve rapid accumulation of intracellular calcium and phosphorylation of Akt, GSK‐3, p70S6K, SHP‐2, MEK1/2, and Stat3, continuous treatment for 72 h induces an increase in PPARγ protein expression. Moreover, chronic activation of the PPARγ pathway in 3T3‐L1 adipocytes with the PPARγ agonist and anti‐diabetic agent, rosiglitazone (BRL 49653), enhances FGF‐21 action to induce tyrosine phosphorylation of FGF receptor‐2. Strikingly, treatment of cells with FGF‐21 and rosiglitazone in combination leads to a pronounced increase in expression of the GLUT1 glucose transporter and a marked synergy in stimulation of glucose transport. Together these results reveal a novel synergy between two regulators of glucose homeostasis, FGF‐21 and PPARγ, and further define FGF‐21 mechanism of action. J. Cell. Physiol. 210: 1–6, 2007. © 2006 Wiley‐Liss, Inc.
Fragmentation behavior of glycated peptides derived from D‐glucose, D‐fructose and D‐ribose in tandem mass spectrometry
Authors: Frolov Andrej , Hoffmann Peter , Hoffmann Ralf
Published: October 2006

Nonenzymatic glycosylation (or glycation) is a common nonenzymatic side‐chain specific sequence‐independent posttranslational modification formed by the reaction of reducing carbohydrates with free amino groups. Thus, proteins can react with aldoses or ketoses to yield Amadori or Heynes compounds, respectively. Here, the fragmentation behavior of D‐glucose and D‐ribose‐derived Amadori peptides as well as D‐fructose‐derived Heynes peptides were studied by collision‐induced fragmentation (CID) after electrospray (ESI) or matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry (MS). All three sugar moieties displayed characteristic fragmentation patterns accompanying the parent and the fragment ions, which could be explained by consecutive losses of water and formaldehyde. Glucose‐derived Amadori parent and fragment ions displayed losses of 18, 36, 54, 72, and 84 u at a characteristic intensity distribution compared with losses of 18, 36, 54, 72, 84, and 96 u for D‐fructose‐derived ions and losses of 18, 36, and 54 u for ribose‐derived ions. Furthermore, each sugar moiety produced indicative lysine‐derived immonium ions that were successfully used in a precursor ion scan analysis to identify Amadori peptides in a tryptic digest of bovine serum albumin (BSA) glycated with D‐glucose. BSA was modified on lysine residues at positions 36, 160, 235, 256, 401, and 548. Copyright © 2006 John Wiley & Sons, Ltd.
Kinetics of inflammatory response of astrocytes induced by TLR 3 and TLR4 ligation
Authors: Krasowska‐Zoladek Alicja , Banaszewska Monika , Kraszpulski Michal , Konat Gregory W.
Published: October 2006

Toll‐like receptors (TLRs) are sentinels of the innate immune system that recognize an array of exogenous and endogenous pathogenic molecules. The ligation of the receptors triggers inflammatory response necessary for pathogen elimination and for the healing process. In the present study we examined inflammatory response of astrocytes elicited by the ligation of TLR3 and TLR4. Astrocytic cultures established from newborn rat brains were exposed to double stranded RNA (dsRNA) and lipopolysaccharide (LPS), the ligands for TLR3 and TLR4, respectively. The expression of cytokine genes was determined by RNase protection assay, and the generation of nitric oxide (NO) was measured by Griess technique. Both ligands upregulated the expression of several cytokines (i.e., IL‐1α, IL‐1β, IL‐6, TNFα, GM‐CSF, LTβ, and TGFβ3) and downregulated the expression of MIF, but have no effect on the expression of IL‐2, IL‐3, IL‐4, IL‐5, IL‐10, TGFβ1, TGFβ2, TNFβ, and IFNγ. Although dsRNA upregulated the expression of IFNβ, LPS did not indicating that the TRIF‐dependent branch of TLR4 signaling is inactive in astrocytes. Proinflammatory response as seen from upregulated cytokine expression and NO generation reached a peak within the first day of exposure, and was subsequently abrogated. The cells also became refractory to subsequent stimulation by the ligands indicating the existence of negative feedback mechanisms that control proinflammatory response in astrocytes. © 2006 Wiley‐Liss, Inc.
Oral administration of metal chelator ameliorates motor dysfunction after a small hemorrhage near the internal capsule in rat
Authors: Masuda Tadashi , Hida Hideki , Kanda Yoshie , Aihara Noritaka , Ohta Kengo , Yamada Kazuo , Nishino Hitoo
Published: October 2006

Cerebral hemorrhage leads to local production of free iron, radicals, cytokines, etc. To investigate whether a decrease of iron‐mediated radical production influences functional recovery after intracerebral hemorrhage (ICH), a modified ICH rat model with a small hemorrhage near the internal capsule (IC) accompanied with relatively severe motor dysfunction was first developed. Then clioquinol (CQ), an iron chelator that reduces hydroxyl radical production, was orally administrated. Injection of different doses of Type IV collagenase (1.4 μl 1–200 U/ml) into the left striatum near the IC in Wistar rats showed that injection of 7.5 U/ml collagenase resulted in a small hemorrhoidal lesion near the IC with relatively severe motor dysfunction (IC model). Retrograde labeling of neurons in the sensory‐motor cortex and axons in the corticospinal tract using Fluoro‐gold (FG) injection into the spinal cord (C3–C4) showed that few labeled neurons in the sensory‐motor cortex were detected in the IC model, FG‐labeled axons disappeared, and FG‐including ED‐1‐positive cells appeared within 24 hr in the IC. Assessments of behavior and histologic analysis after oral administration of CQ in the IC model indicated that oral administration of CQ prevented a decrease of FG‐labeled neurons, and resulted in better motor‐function recovery. CQ inhibited hydrogen peroxide‐induced cell toxicity in oligodendrocytes in vitro, but not in neurons. Our data suggests that CQ ameliorated motor dysfunction after a small hemorrhage near the IC by a mechanism that is related to reduction of chain‐reactive hydroxyl radical production in oligodendrocytes. © 2006 Wiley‐Liss, Inc.
VEGF overexpression enhances striatal neurogenesis in brain of adult rat after a transient middle cerebral artery occlusion
Authors: Wang Yong‐Quan , Guo Xin , Qiu Mei‐Hong , Feng Xiao‐Yuan , Sun Feng‐Yan
Published: October 2006

To elucidate whether vascular endothelial growth factor (VEGF) improves stroke‐induced striatal neurogenesis, we intraventricularly injected human VEGF165‐expressive plasmid (phVEGF) mixed with liposome into adult rats after a transient middle cerebral artery occlusion (MCAO). The results showed that EGFP, a reporter protein, positive cells appeared at 2 hr, further enhanced at 4 hr, reached the maximum at 3 days and still remained at 14 days after a single injection. Treatment with phVEGF increased angiogenesis, as indicated by double staining of vWF, a marker of endothelial cells, and 5′‐bromodeoxyuridine (BrdU), a marker of cell proliferation. The phVEGF treatment dose‐dependently reduced infarct volume of brain at 2 weeks after MCAO. The neuroprotection by VEGF could be obtained when the plasmid was injected within 2 hr after stroke. Moreover, VEGF overexpression significantly increased cell proliferation in the ipsilateral SVZ and the numbers of BrdU+‐CRMP‐4+ and BrdU+‐Tuj1+, two markers of immature newborn neurons, and BrdU+‐MAP‐2+, a marker of mature newborn neurons, cells in the ipsilateral striatum to MCAO. Present results show that VEGF plasmid treatment after stroke can significantly reduce infarct volume and enhance striatal neurogenesis in adult rat brain. This suggests that VEGF overexpression acquires significant functions of neuronal protection and repair in the injured brain, which provides a possibility to develop a novel therapeutic strategy for the patients with stroke. © 2006 Wiley‐Liss, Inc.
Breast reconstruction with the TRAM flap: Pedicled and free
Authors: Serletti Joseph M.
Published: October 2006

Background

Breast cancer is a ubiquitous disease affecting one in seven women. While breast conservation techniques are available for local control of the disease for many patients, not all patients are good candidates for these techniques. Mastectomy, therefore, remains a common method of breast cancer treatment. Methods of reconstruction include implant reconstruction and autogenous reconstruction. The advantages of autogenous reconstruction include the creation of a soft, ptotic breast mound, which tends to match a native contralateral breast both in and out of bra support. Autogenous reconstructions do not tend to change with time and usually do not require periodic revision as seen in implant reconstructions.

Methods

The most common method of autogenous reconstruction is the TRAM flap, either pedicled or free. The TRAM flap employs the redundant excess lower abdominal tissue typically removed during a cosmetic abdominoplasty. This tissue is brought to the mastectomy defect as a pedicled flap, passing subcutaneously from the upper abdomen and into the defect site. The pedicled flap is based upon the superior epigastric vessels. A free TRAM is harvested with the overlying muscle and the attached inferior epigastric vessels. This flap is completely separated from the abdomen and brought to the chest defect where it is anastomosed to either the thoracodorsal or internal mammary vessels. The donor defect within the abdominal wall is repaired with an inlay mesh with both the pedicled and free techniques.

Results

Patient selection criteria usually help determine which technique is used. The advantage of the free flap technique is improved blood supply to the skin island. The free flap, therefore, is used in patients at higher risk for partial flap loss with the pedicled technique. Such high‐risk patients include smokers, the obese, patients with significant medical comorbidities, and patients with prior abdominal surgery. Patients without these risk factors can be expected to achieve good results with either the pedicled or free flap technique.

Conclusion

Autogenous breast reconstruction with the TRAM flap achieves long lasting satisfactory results in most patients with the creation of a soft, naturally ptotic breast mound, which typically matches well a contralateral native breast. J. Surg. Oncol. 2006;94:532–537. © 2006 Wiley‐Liss, Inc.
The Self‐Assembly of Hydroxypropylcellulose and Carboxyl‐Ended Surfactants to Multi‐Morphological Nanoparticles
Authors: Dou Hongjing , Sun Kang , Yang Weihai
Published: October 2006

Summary: The self‐assembly of HPC and carboxyl‐ended surfactants such as Deac was studied in the present paper. Nanoparticles with multi‐morphologies were fabricated from HPC and Deac, and their diameter and morphology can be controlled by adjusting the molar ratio of glucose units and Deac and the environmental pH value. We also demonstrated the ubiquity of fabricating multi‐morphological nanoparticles from HPC and other carboxyl‐ended surfactants by substituting PDFOA for Deac, and it was confirmed by DLS characterization that nanoparticles with multi‐morphologies were formed at pH = 0.1. Thus the proposed approach shows a considerable potential to fabricate polysaccharide‐based multi‐morphological nanoparticles from water‐soluble polysaccharides and carboxyl‐ended surfactants.

A schematic illustration of the self‐assembly of HPC and Deac to multi‐morphological nanoparticles.

magnified image

A schematic illustration of the self‐assembly of HPC and Deac to multi‐morphological nanoparticles.
Soluble and Colorless Poly(ether‐imide)s Based on a Benzonorbornane Bis(ether anhydride) and Trifluoromethyl‐Substituted Aromatic Bis(ether‐amine)s
Authors: Chen Ya‐Yin , Yang Chin‐Ping , Hsiao Sheng‐Huei
Published: October 2006

Summary: A series of organosoluble and colorless fluorinated poly(ether imide)s (IVa‐g) were prepared from 3,6‐bis(3,4‐dicarboxyphenoxy)benzonorbornane dianhydride (I) and various trifluoromethyl (CF3)‐substituted aromatic bis(ether amine)s IIa‐g by a standard two‐step process with thermal and chemical imidization of poly(amic acid) precursors. These poly(ether imide)s had inherent viscosities of 1.02–1.28 dL · g−1 and showed excellent solubility in many organic solvents. They could be solution‐cast into transparent, flexible, and tough films with good mechanical properties. These films were virtually colorless, with an ultraviolet‐visible absorption edge of 372–381 nm and a very low b* value (a yellowness index) of 10.8 to 18.2. The glass‐transition temperatures (Tg) and softening temperatures (Ts) were recorded between 216–292 °C and 209–285 °C, respectively. The decomposition temperature for 10% weight loss all occurred above 472 °C in nitrogen and 481 °C in air, and the char yields at 800 °C in nitrogen were more than 51%. They also showed low dielectric constants of 2.84–3.58 (1 MHz) and moisture absorptions in the range of 0.05–0.19%. In comparison with analogous V series poly(ether imide)s without the CF3 substituents, the IV series ones showed better solubility, lower color intensity, and lower dielectric constants.

A novel series of fluorinated poly(ether imide)s.

magnified image

A novel series of fluorinated poly(ether imide)s.
Multilayer Thin Films by Layer‐by‐Layer Assembly of Hole‐ and Electron‐Transport Polyelectrolytes: Optical and Electrochemical Properties
Authors: Choi Kyungsun , Zentel Rudolf
Published: October 2006

Summary: In this paper, we present the synthesis of a series of p‐type and n‐type semiconducting polyelectrolytes with triarylamine, oxadiazole, thiadiazole and triazine moieties. The synthesized polymeric hole and electron transport materials were examined optically and electrochemically using UV/Vis spectroscopy, PL spectroscopy and CV. Based on the optical and electrochemical data, each of the energy levels were calculated and all values suggested that they were promising hole‐ (p‐type) or electron‐transport (n‐type) materials for devices. Moreover, the synthesized ionic polymers were suitable for LBL thin film deposition from dilute polymer solutions and the multilayers were fully characterized by UV/Vis, PL spectroscopy and CV.

magnified image
Controlled Radical Ab Initio Emulsion Polymerization of n‐Butyl Acrylate by Reverse Iodine Transfer Polymerization (RITP): Effect of the Hydrolytic Disproportionation of Iodine
Authors: Tonnar Jeff , Lacroix‐Desmazes Patrick , Boutevin Bernard
Published: October 2006

Summary: Controlled radical polymerization of n‐butyl acrylate by reverse iodine transfer polymerization (RITP) was achieved in ab initio emulsion polymerization to yield a stable and uncolored latex (particle diameter dp = 106 nm). Hydrolysis of iodine, I2, was responsible for an upward deviation from the targeted molecular weight $\overline M _{{\rm n},{\rm targeted}}$ = 10 400 g · mol−1. The iodide concentration [I−] was followed by an iodide selective electrode and the amount of efficient iodine (33%) was successfully correlated with the experimental molecular weight $\overline M _{{\rm n},{\rm exp}}$ = 31 000 g · mol−1. Finally, a simplified mechanism of RITP in ab initio emulsion polymerization taking into account the iodine hydrolysis was proposed.

Evolution of molecular weight and polydispersity index in RITP of BuA in ab initio emulsion.

magnified image

Evolution of molecular weight and polydispersity index in RITP of BuA in ab initio emulsion.
Proton NMR assignments for R,S‐1,1′‐binaphthol (BN) and R,S‐1,1′‐binaphthyl‐2,2′‐diyl hydrogen phosphate (BNDHP) interacting with bile salt micelles
Authors: Eckenroad Kyle W. , Thompson Laura E. , Strein Timothy G. , Rovnyak David
Published: October 2006

We report proton chemical shifts for two model chiral analytes that are commonly used in the study of micellar electrokinetic capillary chromatography (MEKC), R,S‐1,1′‐binaphthol (1, BN) and R,S‐1,1′‐binaphthyl‐2,2′‐diyl hydrogen phosphate (2, BNDHP), in the absence and presence of monomers and micelles of sodium cholate and sodium deoxycholate. The analytes undergo fast exchange in and out of the micelles, which perturbs the analytes' chemical shifts, and which we use to resolve some resonances that are degenerate at both 300 and 600 MHz. Although BN and BNDHP are simple molecules, the proton assignments are only unambiguously established with the aid of the exchange with micelles, an attractive alternative to other methodologies such as the use of paramagnetic shift reagents which may also cause spectral distortions. We rely also upon 2D‐NOE spectra of samples in the presence of micelles to perform these assignments. Recently published assignments, which were based upon 2D‐COSY spectroscopy, appear to be in error and are corrected here. Finally, we note that these shifts are information‐rich reporters on the nature of the interactions of these model analytes with the micelles. Copyright © 2006 John Wiley & Sons, Ltd.
Neurodevelopment and chronic illness: Mechanisms of disease and treatment
Authors: Armstrong F. Daniel
Published: October 2006

Successful treatment of many childhood diseases once considered terminal has resulted in the emergence of long‐term effects of the disease or consequences of treatment that were previously unrecognized. Many of these long‐term effects involve the central nervous system (CNS) and are developmental in the way that they emerge over time. Because we are now able to observe the natural history of childhood diseases such as sickle cell anemia or HIV, or the consequences of treatment of disease such as leukemia, brain tumors, or kidney disease, we are also able to study a number of biological mechanisms that result in long‐term neurocognitive impairment. While some of the neurodevelopmental outcomes can be directly linked to structural damage of the CNS, other systems (e.g., hematologic, immunologic, pulmonary) appear to play crucial indirect roles in the development of the CNS and neurocognitive abilities because of the way that they affect the course of brain development and activity of the brain across time. Important interactions between acute disease factors, biological mechanisms, age at the time of disease or treatment effect, and disruptions in patterns of development after successful treatment or management all provide support for a neurodevelopmental model of childhood chronic illness. Testing this model may make it possible to more accurately predict the timing and degree of severity of long‐term neurodevelopmental consequences, provide guidance for improved treatment and prevention, and offer better understanding of neurodevelopmental disruptions that occur in other non‐chronic illness related disabilities. MRDD Research Reviews 2006;12:168–173. © 2006 Wiley‐Liss, Inc.
Metric‐driven mesh optimization using a local simulated annealing algorithm
Authors: Acikgoz Nazmiye , Bottasso Carlo L.
Published: October 2006

We report on results obtained with a metric‐driven mesh optimization procedure for simplicial meshes based on the simulated annealing (SA) method. The use of SA improves the chances of removing pathological clusters of bad elements, that have the tendency to lock into frozen configurations in difficult regions of the model such as corners and complex face intersections, prejudicing the overall quality of the final grid. A local version of the algorithm is developed that significantly lowers the computational cost.

Numerical examples illustrate the effectiveness of the proposed methodology, which is compared to a classical greedy Gauss–Seidel optimization. Substantial improvement in the quality of the worst elements of the grid is observed for the local simulated annealing optimization. Furthermore, the method appears to be robust to the choice of the algorithmic parameters. Copyright © 2006 John Wiley & Sons, Ltd.
Cure behavior of unsaturated polyester/modified montmorillonite nanocomposites
Authors: Zhou Yan , Yang Xiaoyun , Jia Demin
Published: October 2006

Dynamic rheology, differential scanning calorimetry and in situ Fourier transform infrared spectroscopy were used to study the cure behavior of unsaturated polyester/modified montmorillonite nanocomposites. The results showed that their gel times increased markedly at the same cure temperature, and that the activation energy of the nanocomposites was higher than that of the pure unsaturated polyester. Their peak temperatures of enthalpy increased as well. The total exotherm of the cure reaction declined and the cure rate decreased. In the curing process of pure unsaturated polyesters, the conversion of styrene was higher than that of the double bonds on unsaturated polyester macromolecular chains. The cure mechanism of the unsaturated polyester/modified montmorillonite changed because of the presence of double bonds in the layers of modified montmorillonite. However, the conversion of styrene in the nanocomposites was lower than that of double bonds on unsaturated polyester chains during cure at room temperature, and the conversion of styrene was increased after post‐curing and was higher than that of the double bonds on unsaturated polyester chains at the end of the cure reaction. Moreover, the degree of reaction of double bonds on unsaturated polyester chains of the nanocomposites was higher than that of unsaturated polyesters. Copyright © 2006 Society of Chemical Industry
Oncology nurses' perceptions of their supportive care for parents with advanced cancer: challenges and educational needs
Authors: Turner Jane , Clavarino Alexandra , Yates Patsy , Hargraves Maryanne , Connors Veronica , Hausmann Sue
Published: October 2006

Despite the emotional impact for children with a parent with advanced cancer, most families receive limited information and support to assist them. A project is underway to determine the acceptability and effectiveness of a supportive and educational intervention for parents with advanced cancer to be delivered by specially trained oncology nurses.

To assess the perceptions of oncology nurses about this role, explore potential challenges, and understand their educational needs, oncology nurses were recruited from three metropolitan hospitals to participate in focus groups. This data was supplemented with data from individual interviews conducted with rurally based nurses unable to participate in focus groups held in a metropolitan location. Four focus groups were held, with 24 participants. Individual telephone interviews were conducted with five nurses.

Nurses identified the emotional burden of the supportive care role as a key challenge, along with health care systems which were not attuned to the needs of families. Attention to self‐care and professional confidence, and access to role‐models emerged as key elements required in education, along with information about the impact of parental cancer on children and their developmental stages, and ways to promote more open parental communicate with children. Copyright © 2006 John Wiley & Sons, Ltd.
Application of Electrical Capacitance Tomography for Bulk Solids Flow Analysis in Silos
Authors: Chaniecki Zbigniew , Dyakowski Tomasz , Niedostatkiewicz Maciej , Sankowski Dominik
Published: October 2006

The paper presents application of electrical capacitance tomography (ECT) for imaging solids distribution in a laboratory scale silo. The data were obtained for both non‐cohesive (dry) and cohesive (wet) sand particles. The static tests show how the local material compression zone influences the distribution of dielectric permittivity in the whole volume of a silo. The images obtained during the dynamic tests show the formation of different flow patterns. Particularly the influence of the roughness of the silo wall, the initial bulk density and the outlet silo's diameter on the changes of the solid concentration profiles have been derived. These results provide useful information for controlling the silo discharging and structural safety.
Application of CT‐Processing to Neutron Radiography Imaging of a Fluidized‐Bed
Authors: Umekawa Hisashi , Furui Shuji , Ozawa Mamoru , Takenaka Nobuyuki
Published: October 2006

CT‐processing is very effective in obtaining 3‐dimensional information for industrial instruments, and several trials have also been applied to fluidized‐beds. In the CT‐processing of fluidized‐beds, X‐rays are used mainly because they are readily availability. Similar processing can be performed by neutron‐rays which penetrate most metals, but not some chemical substances, such as hydrogen, boron, gadolinium, which are opaque to the neutrons. Due to these unique characteristics, neutron radiography can be considered as a suitable visualization method of actual industrial instruments made of metal. Thus, neutron radiography also has significant advantages for the visualization of fluidized‐beds. However, neutron radiography requires a nuclear reactor or an accelerator as the neutron source in order to obtain high quality images, which means that the real time CT‐processing of multiphase flows by neutron radiography is quite difficult. Consequently, CT‐images in this investigation were reconstructed by using time‐averaged visualization images. Although time averaging makes the understanding of the void movement difficult, 3‐dimensional characteristics of the void fraction propagation in fluidized‐beds could be clearly visualized by using test sections with significant non‐uniformity of the fluidized‐gas distribution.
On the existence of non‐supersymmetric black hole attractors for two‐parameter Calabi‐Yau's and attractor equations
Authors: Kaura P. , Misra A.
Published: October 2006

We look for possible nonsupersymmetric black hole attractor solutions for type II compactification on (the mirror of) CY3(2,128) expressed as a degree‐12 hypersurface in WCP4[1,1,2,2,6]. In the process, (a) for points away from the conifold locus, we show that the existence of a non‐supersymmetric attractor along with a consistent choice of fluxes and extremum values of the complex structure moduli, could be connected to the existence of an elliptic curve fibered over C8 which may also be “arithmetic” (in some cases, it is possible to interpret the extremization conditions for the black‐hole superpotential as an endomorphism involving complex multiplication of an arithmetic elliptic curve), and (b) for points near the conifold locus, we show that existence of non‐supersymmetric black‐hole attractors corresponds to a version of A1‐singularity in the space Image(Z6→R2/Z2 (↪R3)) fibered over the complex structure moduli space. The (derivatives of the) effective black hole potential can be thought of as a real (integer) projection in a suitable coordinate patch of the Veronese map: CP5→CP20, fibered over the complex structure moduli space. We also discuss application of Kallosh's attractor equations (which are equivalent to the extremization of the effective black‐hole potential) for nonsupersymmetric attractors and show that (a) for points away from the conifold locus, the attractor equations demand that the attractor solutions be independent of one of the two complex structure moduli, and (b) for points near the conifold locus, the attractor equations imply switching off of one of the six components of the fluxes. Both these features are more obvious using the attractor equations than the extremization of the black hole potential.
Aharonov–Bohm effects in multiwall carbon nanotubes
Authors: Strunk C. , Stojetz B.
Published: October 2006

We investigate quantum transport phenomena in multiwall carbon nanotubes in perpendicular and parallel magnetic field. An efficient gating technique allows for a considerable tuning of the nanotube doping level. We show that the weak localization is strongly suppressed at peaks at certain gate voltages which can be linked with the bottoms of one‐dimensional electronic subbands. In large parallel magnetic field, we observe a superposition of h /2e ‐periodic Altshuler‐Aronov‐Spivak oscillations and an additional h /e ‐periodic contribution, which we attribute to the magnetic field dependence of the band structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
13C NMR and EPR of carbon nanofoam
Authors: Blinc R. , Cevc P. , Arčon D. , Zalar B. , Zorko A. , Apih T. , Milia F. , Madsen N. R. , Christy A. G. , Rode A. V.
Published: October 2006

The 13C NMR spectra of a carbon nanofoam sample, exhibiting a peak in the ZFC magnetic susceptibility, show a single 13C line at room temperature and a two peak structure at 100 K. The splitting and the NMR shifts are however much too small to be associated with true ferromagnetism as for instance observed in TDAE‐C60 below T C. The X‐band EPR spectra show the presence of a least three different paramagnetic clusters with g a = 2.0016, g b = 2.0031, g c = 2.0036 and very different electronic spin–lattice relaxation times. In some samples the CW EPR spectra show an additional rather broad and strongly temperature dependent line shifted to lower fields, which is characteristic of ferromagnetic systems. The results thus show an inhomogeneous super‐paramagnetic or spin‐glass like nature of magnetism in cluster assembled carbon nanofoam rather than homogeneous ferromagnetism. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron transport in Ar+‐irradiated single wall carbon nanotubes
Authors: Skákalová V. , Woo Y.‐S. , Osváth Z. , Biró L. P. , Roth S.
Published: October 2006

We study the effect of Ar+‐irradiation on electrical transport in an individual single wall carbon nanotube (SWNT), a thin SWNT network and a thick SWNT film. The damage to SWNT structure induced by Ar+‐irradiation is characterized by Raman spectroscopy. The electrical conductance both in an individual SWNT and in a thin SWNT network is strongly reduced by highly energetic Ar+ ions. On contrary, a thick SWNT film exhibits an increase of its conductivity as well as of its Young modulus after irradiation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strong coupling in artificial semimagnetic Cd(Mn,Mg)Te quantum dot molecule
Authors: Zaitsev S. V. , Welsch M. K. , Forchel A. , Becker C. R. , Molenkamp L. W. , Bacher G.
Published: October 2006

Exciton photoluminescence in a pair of strongly coupled artificial asymmetric quantum dots (QDs) has been studied in a magnetic field up to 8 T. The QD molecules have been fabricated by a selective interdiffusion technique applied to asymmetric semimagnetic CdTe/Cd(Mg,Mn)Te double quantum wells. The lateral confinement potential within the plane, induced by the diffusion, gives rise to effective zero‐dimensional exciton localization. In contrast to a typically positive exciton Lande g ‐factor, an exciton transition in the non‐magnetic QD demonstrates a nearly zero g ‐factor, indicating a strong electron tunnel coupling between the QDs. The strong coupling results in the formation of an inter‐QDs indirect exciton, which is a ground exciton state at high magnetic field, as found in the experiment and confirmed by our calculations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)