bluuebunny/crossref_metadata_2025 huggingface dataset:
4‐Methyl‐ and 4‐(Halophenyl)pyrimidinium (4‐Halobenzoyl)methylides. Correlation of Structure, Stability, Reactivity, and Biological Activity
Authors: Moldoveanu Costel C. , Mangalagiu Ionel I.
Published: October 2005

For the first time in the cycloimminium ylide series, we present a theoretical and experimental study concerning the correlation between structure, stability, reactivity, and biological activity of 4‐(R)‐pyrimidinium (4‐halobenzoyl)methylides (R = Me and 4‐chlorophenyl; hal = X = F, Cl, Br, I; see 5 and 6 in Scheme 1). The 4‐methylpyrimidinium (4‐halobenzoyl)methylides 5 are relatively stable compounds, while the (4‐chlorophenyl)pyrimidinium (4‐halobenzoyl)methylides 6 are more unstable. Their stability varies with the nature of the substituents at the ylide carbanion and pyrimidinium cation moieties as confirmed by quantum‐chemical calculations. The latter also disclose the possibility to use pyrimidinium ylides as nucleophilic reagents as well as 1,3‐dipoles in reactions with appropriate reagents. The experimental data obtained confirm the calculations concerning the nucleophilicity and reactivity of the ylides 5 and 6. Moreover, the influence of microwave irradiation on the synthesis of the pyrimidinium salts 3 and 4 from pyrimidine and an organic halide is studied and reveals a remarkable reaction‐rate increase under microwave irradiation as compared to classical conditions; this allows the general and facile synthesis of the salts 3 and 4 (Scheme 1, Table 1). The in vitro biological activity of the newly obtained 4‐methylpyrimidine compounds is also tested. Some of them exhibit a remarkable activity against different microorganisms (germs and fungi) which allows to establish structure–activity correlations.
Diterpenes and Disulfides from the Marine Mangrove Plant Bruguiera sexangula var. rhynchopetala
Authors: Bao Shuyun , Deng Zhiwei , Fu Hongzheng , Proksch Peter , Lin Wenhan
Published: October 2005

Phytochemical investigation of the stems of Bruguiera sexangula var. rhynchopetala resulted in the isolation and characterization of four new and seven known secondary metabolites. The new compounds were spectroscopically identified as 17‐hydroxy‐16‐oxobeyer‐9(11)‐en‐19‐al (1), 16,17‐dihydroxy‐19‐nor‐ent‐kaur‐9(11)‐en‐3‐one (2), (16R)‐13,17‐epoxy‐16‐hydroxy‐ent‐kaur‐9(11)‐en‐19‐al (3), and (−)‐3,4‐dihydro‐3‐hydroxy‐7‐methoxy‐2H‐1,5‐benzodithiepine‐6,9‐dione (10). The configurations of the known compounds brugierol (11) and isobrugierol (12) were re‐investigated. Compounds 11 and 12, together with 2,6‐dimethoxy‐1,4‐benzoquinone (13), are proposed to be degradation products of the novel, unusual disulfide 10 (Scheme).
Synthesis of Eburnamine, Isoeburnamine, and Eburnamonine via a Spirocyclic Intermediate
Authors: Ho Tse‐Lok , Chen Chun‐Kuei
Published: October 2005

Racemic eburnamonine (1) was synthesized via 6, an intermediate possessing local symmetry. Cleavage of the cyclopentene subunit led to pentacyclic aldehydes 8a/8b which on subsequent borohydride and Wolff–Kishner reductions gave 12. The final steps included a RuCl3‐catalyzed periodate oxidation and pyridinium chlorochromate (PCC) oxidation. The penultimate intermediates were racemic eburnamine (2) and racemic isoeburnamine (3).
Synthesis of Some New 1,2,4‐Triazole Derivatives by Mitsunobu Chemistry
Authors: Alizadeh Abdolali
Published: October 2005

The reactive 1 : 1 intermediate produced in the reaction between triphenylphosphine and diisopropyl azodicarboxylate has been trapped by isocyanates or isothiocyanates to yield 1,2,4‐triazole derivatives 2 (Scheme 1). The structures of the highly functionalized compounds 2 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, EI‐MS) and by elemental analyses. A mechanism for this type of cyclization is proposed (Scheme 2).
Conformations of the Nine‐Membered Ring in the B‐Nor‐5,10‐secosteroids. X‐Ray and NMR Analysis
Authors: Bjelaković Mira S. , Krstić Natalija M. , Tinant Bernard , Kalvoda Jaroslav , Csanadi Janos , Pavlović Vladimir D.
Published: October 2005

The conformations of (Z)‐ and (E)‐5‐oxo‐B‐nor‐5,10‐secocholest‐1(10)‐en‐3β‐yl acetates (2 and 3, resp.) were examined by a combination of X‐ray crystallographic analysis and NMR spectroscopy, with emphasis on the geometry of the cyclononenone moiety. The 1H‐ and 13C‐NMR spectra showed that the unsaturated nine‐membered ring of (E)‐isomer 3 in C6D6 and (D6)acetone solution exists in a sole conformation of type B1, which is similar to its solid‐state conformation. The (Z)‐isomer 2 in C6D6, CDCl3, and (D6)acetone solution, however, exists in two conformational forms of different families, with different orientation of the carbonyl group, the predominant form (85%) corresponding to the conformation of type A1 and the minor (15%) to the conformation A2 present also in the crystalline state. In this solid‐state conformations of the nine‐membered ring of both compounds, the 19‐Me and 5‐oxo groups are ‘β’‐oriented. The NMR analysis suggests that the nine‐membered ring of 4 has a conformation of type C1 in CDCl3 solution.
Molecular targets in melanoma: Strategies and challenges for diagnosis and therapy
Authors: Herlyn Meenhard
Published: October 2005

In coming years, we expect rapid advances in cutaneous melanoma diagnosis and therapy, because of the incorporation of new technologies into experimental and clinical research. Major discoveries in melanoma are often made by investigators outside the field, and the melanoma research community will need to develop a better means of incorporating these advances into their work, to capitalize on the promise they hold for patients. A far greater level of cooperation between labs and clinics will be to bring new technology‐based discoveries from bench‐to‐bedside and back. Metastatic melanoma should become a treatable disease in the next few years, because specific inhibitors are expected for most major targets. However, major challenges lie ahead in securing funding, building infrastructure and gaining expertise in new technologies. To meet these challenges, multidisciplinary collaborations will be required all the more. © 2005 Wiley‐Liss, Inc.
Poly‐ϵ‐caprolactone/hydroxyapatite composites for bone regeneration: In vitro characterization and human osteoblast response
Authors: Causa F. , Netti P. A. , Ambrosio L. , Ciapetti G. , Baldini N. , Pagani S. , Martini D. , Giunti A.
Published: October 2005

Polycaprolactone (PCL), a semicrystalline linear resorbable aliphatic polyester, is a good candidate as a scaffold for bone tissue engineering, due to its biocompatibility and biodegradability. However, the poor mechanical properties of PCL impair its use as scaffold for hard tissue regeneration, unless mechanical reinforcement is provided. To enhance mechanical properties and promote osteoconductivity, hydroxyapatite (HA) particles were added to the PCL matrix: three PCL‐based composites with different volume ratio of HA (13%, 20%, and 32%) were studied. Mechanical properties and structure were analysed, along with biocompatibility and osteoconductivity. The addition of HA particles (in particular in the range of 20% and 32%) led to a significant improvement in mechanical performance (e.g., elastic modulus) of scaffold. Saos‐2 cells and osteoblasts from human trabecular bone (hOB) retrieved during total hip replacement surgery were seeded onto 3D PCL samples for 1–4 weeks. Following the assessment of cell viability, proliferation, morphology, and ALP release, HA‐loaded PCL was found to improve osteoconduction compared to the PCL alone. The results indicated that PCL represents a potential candidate as an efficient substrate for bone substitution through an accurate balance between structural/ mechanical properties of polymer and biological activities. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Preparation and swelling behavior of chitosan‐based superporous hydrogels for gastric retention application
Authors: Park Hyojin , Park Kinam , Kim Dukjoon
Published: October 2005

Chitosan and glycol chitosan hydrogels were prepared, and their swelling behaviors in acidic solution were studied to investigate their application for gastric retention device. The optimum preparation condition of superporous hydrogels was obtained from the gelation and blowing kinetics measured at varying acidic conditions. Both the swelling rate and swelling ratio of glycol chitosan hydrogels were higher than those of chitosan hydrogels. Swelling behaviors were significantly affected by not only foaming/drying methods but also crosslinking density, as the sizes and structures of pores generated were highly dependent on those preparation conditions. The prepared superporous hydrogels were highly sensitive to pH of swelling media, and showed reversible swelling and de‐swelling behaviors maintaining their mechanical stability. The degradation kinetics in simulated gastric fluid was also studied. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Synthesis and characterization of poly‐α,β‐[N‐(2‐hydroxyethyl)‐L‐aspartamide]‐g‐poly(L‐lactide) biodegradable copolymers as drug carriers
Authors: Peng Tao , Cheng Si‐Xue , Zhuo Ren‐Xi
Published: October 2005

A series of biodegradable amphiphilic graft polymers were successfully synthesized by grafting poly(L‐lactide) (PLLA) sequences onto a water‐soluble polymer poly‐α,β‐[N‐(2‐hydroxyethyl)‐L‐aspartamide] (PHEA) backbone. We established the feasibility of preparing these novel graft polymers by the ring‐opening polymerization initiated by the macroinitiator PHEA bearing hydroxyl groups without adding any catalyst. The successful grafting of PLLA sequences onto the PHEA backbone was verified by combined size exclusion chromatography (SEC) and multiangle laser light scattering (MALLS) analysis. The chemical structures of graft polymers were characterized by FTIR and 1H NMR. The critical micelle concentration (CMC) of the graft polymer was determined by fluorescence probe technique using pyrene. By controlling the feed ratio of the macroinitiator to the monomer, graft polymers with different branch lengths can be obtained. Using the 3‐(4,5 dimethylthiozol‐2‐yl)‐2,5‐diphenyl‐tetrazolium bromide (MTT) assay, the graft copolymer has been proved to have low cytotoxicity. Based on the amphiphilicity of the graft copolymers, nanoparticular drug delivery systems were prepared by the direct dissolution method and the dialysis method. The anticancer drug Tegafur was encapsulated into polymeric nanoparticles, and in vitro drug release behavior was investigated. Transmission electron microscopy (TEM) images demonstrate that these nanoparticles are regularly spherical in shape. The particle size and distribution of the nanoparticles were measured. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Influence of salivary organic substances on the discoloration of esthetic dental materials—A review
Authors: Lee Yong‐Keun , Powers John M.
Published: October 2005

The objective of this article was to review the articles on the interaction of salivary organic substances with resin‐based dental materials and on the interaction of these organic substances with exogenous chemical agents, which results in discoloration. Original scientific articles or reviews on the saliva, acquired pellicle, and the interaction with pellicle and chemical agents related to dental resin‐based materials were reviewed. Salivary esterases can increase or decrease the internal and external discoloration. The formation of acquired pellicle on the surface of a material varies by the properties of material, and the pellicle interacts with denaturation agents, such as tannin and chlorhexidine, to form stains and also adsorbs staining substances. Therefore, for the quality and longevity of restorations, protocols for the evaluation of the influence of organic substances on the extrinsic staining of restorative materials should be included in the evaluation of aesthetic restorative materials. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Manufacturing, mechanical characterization, and in vitro performance of bioactive glass 13–93 fibers
Authors: Pirhonen E. , Niiranen H. , Niemelä T. , Brink M. , Törmälä P.
Published: October 2005

Fibers were manufactured from the bioactive glass 13–93 by melt spinning. The fibers were further characterized by measuring their tensile and flexural strength, and their in vitro performance was characterized by immersing them in simulated body fluid, which analyzed changes in their mass, their flexural strength, and surface reactions. The strength of glass fibers is highly dependent on fiber diameter, test method, and possible surface flaws, for example, cracks due to abrasion. In this study, the thinnest fibers (diameter between 24 and 33 μm) possessed the highest average tensile strength of 861 MPa. The flexural strength was initially 1353.5 MPa and it remained at that level for 2 weeks. The Weibull modulus for both tensile and flexural strength values was initially about 2.1. The flexural strength started to decrease and was only ∼20% of the initial strength after 5 weeks. During the weeks 5–40, only a slight decrease was detected. The flexural modulus decreased steadily from 68 to 40 GPa during this period. The weight of the samples initially decreased due to leaching of ions and further started to increase due to precipitation of calcium phosphate on the fiber surfaces. The mass change of the bioactive glass fibers was dependent on the surface area rather than initial weight of the sample. The compositional analysis of the fiber surface after 24 h and 5 weeks immersion did confirm the initial leaching of ions and later the precipitation of a calcium phosphate layer on the bioactive glass 13–93 fiber surface in vitro. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Cranial anatomy of the spade‐headed amphisbaenian Diplometopon zarudnyi (Squamata, amphisbaenia) based on high‐resolution X‐ray computed tomography
Authors: Maisano Jessica Anderson , Kearney Maureen , Rowe Timothy
Published: October 2005

The skull of the trogonophid amphisbaenian Diplometopon zarudnyi is described from high‐resolution X‐ray computed tomographic (HRXCT) imagery of a whole museum specimen preserved in ETOH. The skull was digitally resliced and disarticulated into individual elements, producing novel visualizations that allow detailed morphological analysis of its three‐dimensionally complex structure. The prefrontal and jugal are absent in Diplometopon. The septomaxilla is present but hidden entirely from superficial view. In contrast to previous studies, we recognize a splenial fused to the compound bone of the mandible and a squamosal fused to the otic–occipital complex. Comparison of Diplometopon to the two other amphisbaenians previously described in comparable detail, Rhineura hatcherii and Amphisbaena alba, reveals a mosaic of cranial similarities and differences. Both Diplometopon and Rhineura exhibit a craniofacial angulation and expanded rostral blade related to use of the head as a digging tool, but the detailed architecture of these features is quite different. Additionally, whereas the snout of Rhineura exhibits a high degree of sculpturing and sensory innervation, this is not the case in Diplometopon. Unlike in Rhineura and Amphisbaena, the cranial elements of Diplometopon do not exhibit an extensive degree of overlap or complex interlocking sutures; instead, most of the cranial elements lie in loose apposition to each other. The degree to which this mosaic of features reflects functional demands, shared ancestry, and/or convergence is unclear in the absence of a stable hypothesis of amphisbaenian phylogeny. J. Morphol. © 2005 Wiley‐Liss, Inc.
Desmosomes in uterine epithelial cells decrease at the time of implantation: An ultrastructural and morphometric study
Authors: Preston Amanda M. , Lindsay Laura A. , Murphy Christopher R.
Published: October 2005

Displacement of uterine epithelial cells is an important aspect of implantation in the rat and other species, allowing invasion of the blastocyst into the endometrial stroma. Desmosomes, which are part of the lateral junctional complex, function in cell‐to‐cell adhesion, and are therefore likely to be involved in displacement of uterine epithelial cells at the time of implantation. This study used transmission electron microscopy to study rat uterine epithelial cells during the peri‐implantation period to investigate the change in the number of structural desmosomes along the lateral plasma membrane of uterine epithelial cells. We found a significant decrease in the number of desmosomes along the entire lateral plasma membrane as pregnancy progressed. Furthermore, there were also significant decreases in the number of desmosomes on the apical portion of the lateral plasma membrane between all days of pregnancy examined. In addition, on day 6 of pregnancy, the time of attachment, desmosomes were larger and seen as “giant desmosomes.” For the first time, this study has shown that there is a significant reduction in cell height and actual number of ultrastructurally observable desmosomes at the time of implantation in the rat. It is proposed that this reduction in desmosome number leads to a decrease in lateral adhesion between uterine epithelial cells at the time of implantation, and hence is involved in the loss of uterine epithelial cells to facilitate blastocyst invasion. J. Morphol. © 2005 Wiley‐Liss, Inc.
Gas‐phase tautomers of protonated 1‐methylcytosine. Preparation, energetics, and dissociation mechanisms
Authors: Yao Chunxiang , Cuadrado‐Peinado Maria L. , Polášek Miroslav , Tureček František
Published: October 2005

Tautomers of 1‐methylcytosine that are protonated at N‐3 (1+) and C‐5 (2+) have been specifically synthesized in the gas phase and characterized by tandem mass spectrometry and quantum chemical calculations. Ion 1+ is the most stable tautomer in aqueous and methanol solution and is likely to be formed by electrospray ionization of 1‐methylcytosine and transferred in the gas phase. Gas‐phase protonation of 1‐methylcytosine produces a mixture of 1+ and the O‐2‐protonated tautomer (3+), which are nearly isoenergetic. Dissociative ionization of 6‐ethyl‐5,6‐dihydro‐1‐methylcytosine selectively forms isomer 2+. Upon collisional activation, ions 1+ and 3+ dissociate by loss of ammonia and [C,H,N,O], whose mechanisms have been established by deuterium labeling and ab initio calculations. The main dissociations of 2+ following collisional activation are losses of CH2CNH and HNCO. The mechanisms of these dissociations have been elucidated by deuterium labeling and theoretical calculations. Copyright © 2005 John Wiley & Sons, Ltd.
Ion/molecule reactions in a miniature RIT mass spectrometer
Authors: Chen Huanwen , Xu Ruifeng , Chen Hao , Cooks R. Graham , Ouyang Zheng
Published: October 2005

Ion/molecule reactions were explored in a newly developed miniature mass spectrometer fitted with a rectilinear ion trap (RIT) mass analyzer. The tandem mass spectrometry performance of this instrument is demonstrated using collision induced dissociation (CID) and ion/molecule reactions. The latter includes Eberlin transacetalization reactions and electrophilic additions. Selective detection of the chemical warfare simulant dimethyl methyl phosphonate (DMMP) was achieved through selective Eberlin reactions of its characteristic phosphonium fragment ion CH3OP+(O)CH3 (m/z 93), with 1,4‐dioxane or 1,3‐dioxolane. Efficient adduct formation as a result of electrophilic attack by the phosphonium ion on various nucleophilic reagents, including 1,1,3,3‐tetramethyl urea, methanesulfonic acid methyl ester, dimethyl sulfoxide and methyl salicylate, was also observed using the RIT device. The product ions of these reactions were analyzed using CID and the characteristic fragmentation patterns of the ionic addition products were recorded using multiple‐stage experiments in the miniature RIT instrument. This study clearly demonstrates that a small, home‐built, miniature RIT mass spectrometer can be used to perform analytically useful ion/molecule reactions and also that instruments like this have the potential to provide a portable platform for in situ detection of organophosphorus esters and related compounds with high specificity using tandem mass spectrometry. Copyright © 2005 John Wiley & Sons, Ltd.
Variceal hemorrhage and cystic fibrosis: Outcomes and implications for liver transplantation
Authors: Gooding Ian , Dondos Vicky , Gyi Khin Ma , Hodson Margaret , Westaby David
Published: October 2005

Autopsy and imaging studies show that liver involvement is common in cystic fibrosis. However, complications of chronic liver disease including portal hypertension and variceal bleeding are infrequently encountered, and the degree to which variceal hemorrhage affects prognosis in cystic fibrosis is unclear. This uncertainty has lead to debate as to whether liver transplantation is indicated in these patients. We describe a case series of 18 patients and compare their survival with a control group of cystic fibrosis patients without liver disease. The median age at first bleed was 20.0 years (range 9.7–30.9). The median survival after first bleed was 8.4 years, compared to 13.0 years in the control group (

P

= 0.15). A total of 14 patients have died, 9 from respiratory disease with no discernable contribution from their liver disease. Liver disease contributed to 4 deaths. Only 1 patient suffered a fatal hemorrhage, which may have been either variceal or bronchial in origin. Long-term survival is a frequent occurrence in patients with cystic fibrosis who suffer variceal hemorrhage, and age at death is comparable to the general cystic fibrosis population. In conclusion, this suggests that liver transplantation is not indicated in these patients without additional features of liver decompensation. (Liver Transpl 2005.)
High preoperative recipient plasma 7β-hydroxycholesterol is associated with initial poor graft function after liver transplantation
Authors: Corradini Stefano Ginanni , Micheletta Fausta , Natoli Silvia , Iappelli Massimo , Di Angelantonio Emanuele , De Marco Rosanna , Elisei Walter , Siciliano Maria , Rossi Massimo , Berloco Pasquale , Attili Adolfo Francesco , Diczfalusy Ulf , Iuliano Luigi
Published: October 2005

Oxidative stress is implicated in the pathogenesis of hepatic ischemia-reperfusion injury, a major determinant of initial poor graft function (IPGF) after orthotopic liver transplantation (OLT). We prospectively investigated the association between the recipient plasma preoperative oxidative stress and the occurrence of IPGF after deceased-donor OLT and indirectly studied the source—hepatic or extra-hepatic—of systemic oxidative stress in vivo in cirrhosis. We used a recently developed specific and sensitive mass spectrometry assay to measure 7β-hydroxycholesterol and 7-ketocholesterol (oxysterols), markers of oxidative stress, in biological matrices. At univariate analysis, preoperative recipient 7β-hydroxycholesterol plasma concentration was significantly higher in transplants with subsequent IPGF (n = 9) compared with those with initial good graft function (IGGF; n = 23) [mean ± SD: 30.63 ± 26.42 and 11.57 ± 15.76 ng/mL, respectively] (

P

= 0.017). In a logistic regression model, which included also the Model for End-Stage Liver Disease (MELD) score, 7β-hydroxycholesterol plasma concentration was an independent predictor of IPGF with an odds ratio of 1.17 (95% CI, 1.02–1.33,

P

= 0.028). Patients with cirrhosis (n = 32) had increased oxysterol plasma levels compared with healthy controls (n = 49); livers with cirrhosis (n = 21), however, had oxysterol content comparable with normal livers obtained from organ donors (n = 19). Oxysterols persisted elevated in plasma 1 month after OLT (n = 23). In conclusion, cirrhosis presents upregulated systemic oxidative stress likely of extrahepatic source that is associated with graft failure after OLT. (Liver Transpl 2005.)
CYTE‐I‐HD: Phase I dose finding and tolerability study of cysteamine (Cystagon) in Huntington's disease
Authors: Dubinsky Richard , Gray Carolyn
Published: October 2005

Cystamine, an inhibitor of transglutaminases, slows progression of Huntington's disease in the murine model by approximately 20%. Cysteamine, the dimer of cystamine, is an orphan drug approved for the treatment of nephropathic cystinosis and has a similar benefit in the murine model but with a narrower therapeutic window. In a single‐center open‐label study, we determined the maximum tolerable dose (MTD) and side effects of cysteamine in people with Huntington's disease. Cysteamine was started at a dose of 10 mg/kg per day, divided into four doses, and increased by 10 mg/kg per day weekly until the development of intolerable side effects or a maximum dose of 70 mg/kg per day. Of the 9 subjects, 1 had an MTD of 10 mg/kg per day, 1 had an MTD of 20 mg/kg per day, the maximum dose was 30 mg/kg per day for 2, 40 mg/kg per day for 2, and 50 mg/kg per day for 3. Dose‐limiting side effects were motoric impairment in 5 and nausea in 4. The dose found tolerable by 8 of the subjects was 20 mg/kg per day. All had a noticeable hydrogen sulfide odor at doses of 40 mg/kg per day or higher. We conclude that, at a dose of 20 mg/kg per day, cysteamine was tolerable in people with Huntington's disease. Nausea and motoric impairment were the dose‐limiting side effects. © 2005 Movement Disorder Society
Cardiac conduction alterations in a French family with amyloidosis of the finnish type with the p.Asp187Tyr mutation in the GSN gene
Authors: Chastan Nathalie , Baert‐Desurmont Stéphanie , Saugier‐Veber Pascale , Dérumeaux Geneviève , Cabot Annick , Frébourg Thierry , Hannequin Didier
Published: October 2005

Familial amyloidosis of the Finnish type (FAF) is a rare autosomal‐dominant disorder caused by the accumulation of a 71–amino acid amyloidogenic fragment of mutant gelsolin, an actin‐modulating protein. The main symptoms include corneal lattice dystrophy, progressive cranial and peripheral neuropathy, and skin changes. To date, only two mutations in the GSN gene have been described: the p.Asp187Asn mutation in most patients and the p.Asp187Tyr mutation in a Danish and Czech family. We report on the third family with the p.Asp187Tyr mutation and the first French FAF family. Severe cardiac conduction alterations in three patients were mainly caused by cardiac sympathetic denervation. These findings demonstrate the cardiological involvement of the FAF phenotype and suggest that cardiological follow‐up is required in FAF patients. Muscle Nerve, 2006
Abnormal expression of proteoglycans in Ullrich's disease with collagen VI deficiency
Authors: Higashi Keiko , Higuchi Itsuro , Niiyama Takahito , Uchida Yuichi , Shiraishi Tadafumi , Hashiguchi Akihiro , Saito Akiko , Horikiri Takashi , Suehara Masahito , Arimura Kimiyoshi , Osame Mitsuhiro
Published: October 2005

Patients with Ullrich's disease have generalized muscle weakness, multiple contractures of the proximal joints, and hyperextensibility of the distal joints. Recently we found a marked reduction of fibronectin receptors in the skin and cultured fibroblasts of two patients with Ullrich's disease with collagen VI deficiency, and speculated that an abnormality of cell adhesion may be involved in the pathogenesis of the disease. In this study, we investigated the expression of proteoglycans and adhesion molecules in Ullrich's disease and other muscle diseases. We found a reduction of NG2 proteoglycan in the membrane of skeletal muscle but not in the skin in Ullrich's disease. By contrast, we found the upregulation of tenascin C in the extracellular matrix of skeletal muscle in Ullrich's disease. Our findings suggest that abnormal expression of proteoglycans and adhesion molecules may be involved in the pathogenesis of the dystrophic muscle changes in Ullrich's disease. Muscle Nerve, 2006
Pulmonary predictors of survival in amyotrophic lateral sclerosis: Use in clinical trial design
Authors: Schmidt Eric P. , Drachman Daniel B. , Wiener Charles M. , Clawson Lora , Kimball Richard , Lechtzin Noah
Published: October 2005

The rapidity of progression of amyotrophic lateral sclerosis (ALS) to death or respiratory failure impacts patients, clinicians, and clinical investigators. This study compared the abilities of various pulmonary function tests to predict tracheostomy‐free survival. We evaluated 95 ALS patients by determining upright and supine forced vital capacity (FVC), maximal inspiratory (MIP) and expiratory (MEP) pressures, arterial partial pressure of carbon dioxide (PaCO2), and transdiaphragmatic sniff pressures (Pdi‐sniff). Tracheostomy‐free survival time was measured from the date of spirometry. Supine FVC, upright FVC, MIP, MEP, and Pdi‐sniff were significantly associated with tracheostomy‐free survival after controlling for nonpulmonary factors, whereas PaCO2 was not. A normal supine FVC, MIP, or MEP was highly predictive for one‐year survival. These tests are well suited to predict survival for trial enrollment and patient counseling. Supine FVC's simplicity of use and availability to ALS investigators makes it a particularly attractive predictor of one‐year survival in ALS. Muscle Nerve, 2005
Differential response of heat shock proteins to hindlimb unloading and reloading in the soleus
Authors: Lawler John M. , Song Wook , Kwak Hyo‐Bum
Published: October 2005

Hindlimb unloading (HU) results in oxidative stress, skeletal muscle atrophy, and increased damage upon reloading. Heat shock proteins (HSPs) protect against oxidative stress. However, it is unknown whether HSPs are depressed with long‐term unloading (28 days) or reloading. We tested the hypotheses that long‐term HU would depress Hsp70 and Hsp25 pathways, whereas reloading would allow recovery in the soleus. Adult Sprague‐Dawley rats were divided into three groups: controls; HU for 28 days; and HU + 7 days of reloading (HU‐R). Soleus mass decreased with HU, and did not recover to control values with reloading. Hsp70 decreased with HU (−78.5%) and did not recover with HU‐R (−81.4%). Upstream heat shock factor‐1 was depressed with HU and HU‐R. Hsp25 was reduced with HU, but recovered with reloading. Downstream of Hsp25, NADP‐specific isocitrate dehydrogenase and glutathione peroxidase decreased with unloading, but only NADP‐specific isocitrate dehydrogenase recovered with HU‐R. Lipid peroxidation increased in both HU and HU‐R. These data indicate that prolonged unloading and subsequent reloading results in complex, differential regulation of Hsp70 and Hsp25 pathways in the rat soleus muscle. Thus dysregulation and uncoupling of the Hsp70 and Hsp25 pathways may lead not only to muscle atrophy with prolonged unloading, but also impaired recovery of muscle mass during early reloading. Muscle Nerve, 2006
Analysis of macamides in samples of Maca (Lepidium meyenii) by HPLC‐UV‐MS/MS
Authors: McCollom Megan M. , Villinski Jacquelyn R. , McPhail Kerry L. , Craker Lyle E. , Gafner Stefan
Published: October 2005

The macamides are a distinct class of secondary metabolites that have so far been found only in Lepidium meyenii Walp. (Maca). Using HPLC‐UV‐MS/MS, the main macamides have been identiﬁed as n‐benzylhexadecanamide, n‐benzyl‐(9Z)‐octadecenamide, n‐benzyl‐(9Z, 12Z)‐octadecadienamide, n‐benzyl‐(9Z, 12Z, 15Z)‐octadecatrienamide and n‐benzyloctadecanamide. The identities of n‐benzyl‐(9Z)‐octadecenamide and n‐benzyl‐(9Z, 12Z)‐octadecadienamide were conﬁrmed by comparison of chromatographic and spectral properties with synthetic analogues. Total macamides have been quantiﬁed by HPLC‐UV in plant material from different vendors using n‐benzylhexadecanamide as an external standard. The amount of macamides in the dried plant material ranged from 0.0016 to 0.0123%. Copyright © 2005 John Wiley & Sons, Ltd.
The LEGO toolbox: Supramolecular building blocks by nitroxide‐mediated controlled radical polymerization
Authors: Lohmeijer Bas G. G. , Schubert Ulrich S.
Published: October 2005

A terpyridine‐functionalized alkoxyamine unimolecular initiator was used for the nitroxide‐mediated controlled living radical polymerization ofn‐butylacrylate,N,N‐dimethylacrylamide, 4‐vinylpyridine, 2‐vinylpyridine, and isoprene. For the former three monomers, the kinetics were studied. All polymerizations resulted in well‐defined polymers having a single terpyridine ligand at the chain end and narrow polydispersity indices. The obtained polymers are valuable building blocks for metallo‐supramolecular polymers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6331–6344, 2005
Aromatic homo‐ and copolyesters from naturally occurring monosaccharides: PET and PEI analogs derived from L‐arabinitol and xylitol
Authors: Zamora Francisca , Hakkou Khalid , Alla Abdelilah , Espartero José L. , Muñoz‐Guerra Sebastián , Galbis Juan A.
Published: October 2005

The synthesis and characterization of new aromatic homo‐ and copolyesters based on l‐arabinitol and xylitol are described. These polymers were obtained by polycondensation reaction of the 2,3,4‐tri‐O‐methyl‐l‐arabinitol or 2,3,4‐tri‐O‐methyl‐xylitol, or their mixtures with ethylene glycol, with terephthaloyl chloride or isophthaloyl chloride in o‐dichlorobenzene or in the melt phase from the corresponding methyl phthalates. All the polymers were characterized by GPC, IR, and NMR. Their Mw values ranged between 11,500 and 46,500, with polydispersities from 1.5 to 2.3. They were found to be soluble in chloroform, but insoluble in water. In contrast with the homopolymers completely made with EG, they showed a significant hygroscopicity. DSC and TGA studies showed that the melting temperature of polyethylene terephthalate is depressed by the presence of pentitol units, whereas the thermal stability is kept above 350 °C. Only copolyesters containing 10% or less of pentitol units showed melting and produced X‐ray diffraction patterns characteristic of crystalline material. d‐Arabinitol‐based homopolyesters appeared to be more crystalline than those derived from xylitol and also presented a higher thermal stability. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6394–6410, 2005
Synthesis of water‐soluble cationic polymers with star‐like structure based on cyclodextrin core via ATRP
Authors: Li Jianshu , Xiao Huining , Kim Young Shin , Lowe Tao Lu
Published: October 2005

A range of novel cationic star‐like polymers (Star‐P(MeDMA)s) were synthesized through atom transfer radical polymerization (ATRP) by core‐first method, using a β‐cyclodextrin initiator with 21 initiation sites (21Br‐β‐CD). Methyl chloride‐quaternized 2‐(dimethylamino)ethyl methacrylate (MeDMA) was polymerized in an aqueous medium using 21Br‐β‐CD, Cu(I)Br, and 2,2′‐dipyridyl as an initiator, catalyst, and ligand, respectively. The effects of polymerization temperature and monomer/initiator ratios on the degree and kinetics of polymerization were investigated. The molecular weights, hydrodynamic sizes, and charge densities of the quaternized polymers were characterized using gel permeation chromatography (GPC), dynamic light scattering (DLS), and colloidal titration, respectively. The results demonstrated that the moderate aqueous solubility of the 21Br‐β‐CD initiator had significant impact on the physicochemical properties of the obtained star polymers. The polymerization of 500/1/2/5 ([M]0/[I]0/[Cu(I)0/[L]0]) at 90 °C for 6 h was found to be the best condition to synthesize the proposed cationic star polymer with well‐defined structures in aqueous medium. The nonlinear relationship between the apparent charge density and the particle size of the cationic star polymers was further revealed by GPC and DLS measurements. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6345–6354, 2005
Synthesis of poly(styrene‐block‐tert‐butyl acrylate) star polymers by atom transfer radical polymerization and micellization of their hydrolyzed polymers
Authors: Abraham Sinoj , Ha Chang‐Sik , Kim Il
Published: October 2005

A series of poly(styrene‐block‐tert‐butyl acrylate) heteroatom star block copolymers having various block lengths were prepared by atom transfer radical polymerization (ATRP), using an “as synthesized” cynurate modified trifunctional initiator. The structure of the star polymers was confirmed by the characterization of the individual arms resulting from hydrolysis. Amphiphilic poly(styrene‐block‐acrylic acid) star copolymers were further synthesized by hydrolyzing PtBA blocks using anhydrous trifluoroacetic acid. The characterization data are reported from analyses using gel permeation chromatography, infrared, 1H and 13C NMR spectroscopies. The stable micelle solution was prepared by dialyzing the solution of these polymers in N,N‐dimethylformamide against deionized water. The temperature‐induced associating behavior of these amphiphilic star polymers were studied using dynamic laser light scattering spectroscopy. The hydrodynamic diameter of both micelles and unassociated chains were obtained in the same solution using light scattering cumulant's calculation method. The homogeneity and the size distribution of the micelle population in the solution were determined using centrifuge/sedimentation particle size distribution analyzer. Field emission scanning electron microscope was used to visualize the size of the micelles formed and the micellar aggregates. The influence of the temperature on the viscosity of the micelle solution was studied using an Ubbelohde viscometer. Thermodynamics of micellization of these block copolymers were also investigated. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6367–6378, 2005
Dendrimer‐star polymer and block copolymer prepared by reversible addition‐fragmentation chain transfer (RAFT) polymerization with dendritic chain transfer agent
Authors: Hong Chun‐Yan , You Ye‐Zi , Liu Jun , Pan Cai‐Yuan
Published: October 2005

A new reversible addition‐fragmentation chain transfer (RAFT) agent, dendritic polyester with 16 dithiobenzoate terminal groups, was prepared and used in the RAFT polymerization of styrene (St) to produce star polystyrene (PSt) with a dendrimer core. It was found that this polymerization was of living characters, the molecular weight of the dendrimer‐star polymers could be controlled and the polydispersities were narrow. The dendrimer‐star block copolymers of St and methyl acrylate (MA) were also prepared by the successive RAFT polymerization using the dendrimer‐star PSt as macro chain transfer agent. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6379–6393, 2005
Influence of niobium impurity on spin density in metallic iron
Authors: Błachowski A. , Ruebenbauer K. , Żukrowski J.
Published: October 2005

Random alloys of Nb in α‐Fe with the Nb concentration up to about 5 at.% were investigated by means of Mössbauer spectroscopy at room temperature vs. Nb concentration. A solid solution saturates at about 2.3 at.% of Nb. Non‐stoichiometric Fe2Nb phase rich in Fe precipitates at higher Nb concentrations leaving α‐Fe phase with about 1.6 at.% of Nb. The spin density of the iron atom is influenced in the α phase by the Nb atoms residing as nearest neighbours or second nearest neighbours. More distant impurities have no effect on the hyperfine parameters of Fe. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low frequency conductivity study of gallium‐substituted magnesium–copper spinel ferrite
Authors: Kaiser M. , Ata‐Allah S. S.
Published: October 2005

Mixed ferrites with the chemical formula Mg0.5Cu0.5GaxFe2–xO4 (0.0 ≤ x ≤ 0.5) were prepared by a ceramic route. X‐ray diffraction results confirmed the presence of single‐phase spinel structure for these samples. Electrical properties of these ferrites at various compositions were investigated from room temperature up to 550 K in the frequency range 102–105 Hz. The obtained results revealed semiconductor behavior at high frequency and metallic behavior at low frequency in these materials. All studied compositions exhibit a transition with a change in the slope of the conductivity versus temperature curve. The obtained transition temperature TC is found to decrease linearly with increasing Ga concentration. As Ga substitutes Fe in these compounds the activation energy for electrical conduction in the ferrimagnetic region (Ef) has a small variation with frequency. In contrast, the activation energy in the paramagnetic region (Ep) shows undefined behavior reflecting the nature of this disordered state. The relation of the universal exponent s with temperature gives evidence for the presence of the large overlap polaron (LOP) hopping conduction mechanism in these compounds. The obtained results are explained in the light of the cation–anion–cation and cation–cation interactions present over the octahedral B‐sites in the spinel structure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum phase transition in a spin‐½ XX chain with three‐spin and uniform long‐range interactions
Authors: Lou Ping
Published: October 2005

A spin‐½ XX chain with three‐spin and uniform long‐range interactions among the z components of the spins is constructed. Based upon the model, using the Jordan–Wigner transformation, the thermodynamic quantities and spin transports of the system are evaluated exactly. The phase diagram together with the key parameters characterizing quantum phase transitions is presented. It is noted that, similarly to classical first‐order phase transitions, there are also the metastable states “supercooled” and “superheated” in the first‐order quantum phase transitions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cell Distribution Profiles in Three‐Dimensional Scaffolds with Inverted‐Colloidal‐Crystal Geometry: Modeling and Experimental Investigations
Authors: Shanbhag Sachin , Wang Shaopeng , Kotov Nicholas A.
Published: October 2005

Limited ingrowth of stromal cells is observed when a three‐dimensionally ordered scaffold possessing inverted‐colloidal‐crystal geometry is used to culture adherent cells. In this work, a computational model explaining, as well as predicting, experimental cell distributions is developed. It incorporates a modified Contois cell‐growth model that includes the effects of nutrient saturation, competitive product inhibition, and cell‐contact inhibition to describe the scaffold–cell system. Our results agree with the hypothesis that the rapid growth of cells on the surface of the scaffold depletes the nutrient supply to the core, resulting in the preferential growth on the exterior of the scaffold. When the cells are cultured in a scaffold subjected to a uniform velocity field, they penetrate to a greater extent into the scaffold core. Alternative seeding and culture strategies are suggested and evaluated.
Physicochemical Evaluation of the Hot‐Injection Method, a Synthesis Route for Monodisperse Nanocrystals
Authors: de Mello Donegá Celso , Liljeroth Peter , Vanmaekelbergh Daniel
Published: October 2005

The quintessence of the hot‐injection method, a synthesis route for monodisperse, highly luminescent semiconductor nanocrystals, is reviewed. The separate stages of nucleation and growth of the nanocrystals are discussed in the framework of classical nucleation theory and an equilibrium model proposed by Debye. We also review the numerous adaptations of the original synthesis that currently provide colloidal nanocrystals with well‐defined, size‐dependent optical, electrical, and magnetic properties. The availability of these remarkable materials is one of the most promising developments in nanoscience and nanotechnology.
Revision Surgery after Carpal Tunnel Release –Analysis of the Pathology in 200 Cases during a 2 Year Period
Authors: STÜTZ N. , GOHRITZ A. , VAN SCHOONHOVEN J. , LANZ U.
Published: October 2005

Carpal tunnel release (CTR) is regarded as a common and successful operative procedure in hand surgery. However, an increasing number of patients with complications have been referred to our hospital. This retrospective investigation was undertaken to clarify the reasons for persisting or recurrent symptoms in 200 patients who underwent secondary exploration during a 26 month period at a single institution. In 108 cases, the flexor retinaculum was found to have been released incompletely. In 12 patients, a nerve laceration had occurred during the primary intervention. In 46 patients, symptoms were due to the nerve being tethered in scar tissue. The re-exploration revealed circumferential fibrosis around and within the median nerve in 17 patients and a tumour in the carpal tunnel in four patients. In 13 patients, no specific reason was found for recurrence of symptoms. We conclude that CTR seems to be a widely underestimated procedure and revision surgery could be largely avoided by reducing technical errors during the primary operation.
Paleoenvironmental records of water level and climatic changes from the middle to late holocene at a Lake Erie coastal wetland, Ontario, Canada
Authors: Finkelstein Sarah A. , Davis Anthony M.
Published: October 2005

Pollen and diatom assemblages, and peat stratigraphies, from a coastal wetland on the northern shore of Lake Erie were used to analyze water level and climatic changes since the middle Holocene and their effects on wetland plant communities. Peat deposition began 4700 cal yr B.P. during the Nipissing II transgression, which was driven by isostatic rebound. At that time, a diatom-rich wild rice marsh existed at the site. Water level dropped at the end of the Nipissing rise at least 2 m within 200 yr, leading to the development of shallower-water plant communities and an environment too dry for most diatoms to persist. The sharp decline in water level was probably driven primarily by outlet incision, but climate likely played some role. The paleoecological records provide evidence for post-Nipissing century-scale transgressions occurring around 2300, 1160, 700 and 450 cal yr B.P. The chronology for these transgressions correlates with other studies from the region and implies climatic forcing. Peat inception in shallow sloughs across part of the study area around 700 cal yr B.P. coincides with the Little Ice Age. These records, considered alongside others from the region, suggest that the Little Ice Age may have resulted in a wetter climate across the eastern Great Lakes region.
Geochronology of the Nabwal Hills: a record of earliest magmatism in the northern Kenyan Rift Valley
Authors: McDOUGALL IAN , WATKINS RONALD T.
Published: October 2005

The Nabwal Hills, northeast of Lake Turkana, contain a record of magmatism associated with the initiation and early development of the East African Rift System in northernmost Kenya. The predominantly volcanic Asille Group, 1400 m thick, directly overlies metamorphic basement and comprises a sequence of basaltic lava flows with significant intervals of rhyolitic pyroclastic units, and minor intercalations of fluviatile sediments. The basement gneisses yield K–Ar cooling ages on biotite of 510 and 522 Ma, typically Pan-African. The 40Ar–39Ar ages on alkali feldspar crystals from the rhyolitic units are concordant and show that the Asille Group spans an interval from at least 34.3 to 15.8 Ma, continuing to at least as young as 13 Ma based on previous measurements. Vertebrate fossil sites, containing primate remains, at Irile and Nabwal are shown to be 17 ± 2 Ma old, Early Miocene, based upon K–Ar age measurements on immediately overlying basalts. Variably reliable whole rock K–Ar ages, determined on basalt samples from low in the sequence, indicate that volcanism commenced as early as 34.8 Ma ago. The overall geochronological results show that magmatism in the Nabwal Hills began about 35 Ma ago in Late Eocene times, interpreted as the time of initiation of crustal extension that led to the development of this segment of the East African Rift System. The Asille Group is tilted about 6° to the SSW. This tilting occurred later than 13 Ma ago, and prior to the eruption of the flat-lying Gombe Group basalts. These basalts may have begun erupting about 6 Ma ago in Late Miocene times, although much of this volcanism occurred between about 3.9 and 4.2 Ma ago in Pliocene times. It is suggested that the main rifting, which continues today, commenced in Late Miocene times, less than 13 Ma ago, and is partly reflected in the tilting of the Asille Group.