bluuebunny/crossref_metadata_2025 huggingface dataset:
Apoptosis and gene expression of collagenases but not gelatinases in rabbit disc fragment cultures
Authors: Haschtmann Daniel , Ferguson Stephen J. , Stoyanov Jivko V.
Published: June 2008

Object

The object of this study was to characterize the biological response of isolated intervertebral disc fragments to in vitro culture conditions with respect to cell death and inflammatory and catabolic changes. The acquired data could help to gain a better understanding of the biological reaction of disc tissue when exposed to environmental changes along with altered nutritional and osmotic conditions, as are encountered in different in vitro disc models or disc diseases in vivo.

Methods

Intervertebral disc anulus fragments were isolated from Burgundy rabbits and cultured in standard media for 3 days. The disc fragments were analyzed for their swelling properties, proteoglycan loss on histological studies, lactate dehydrogenase activity, apoptosis, gene expression of collagenases and gelatinases, and for proinflammatory(MCP-1, IL-8,andIL-6)and apoptosis-associated(TNF-α, Fas-L, and caspase 3)genes.

Results

The results demonstrate that disc specimens were swelling, and a loss of proteoglycans with disarrangement of anulus architecture was observed. The disc cells underwent rapid apoptosis with upregulation of various proinflammatory genes. Both collagenases, matrix metalloproteinase(MMP)–1andMMP-13, were increasingly transcribed, whereas the gelatinasesMMP-2andMMP-9did not respond or were downregulated.

Conclusions

Cultured disc fragments swell and undergo necrotic and apoptotic cell death combined with a catabolic gene response and gene expression of proinflammatory and chemoattractant proteins. Some of these findings have been demonstrated before in various spinal disorders. In addition, disc fragments are not suitable for long-term culture if a stable disc metabolism is desired, and the described changes have to be considered when using isolated disc material for in vitro cultures.
Spinal osteochondroma: spectrum of a rare disease
Authors: Srikantha Umesh , Bhagavatula Indira Devi , Satyanarayana Satish , Somanna Sampath , Chandramouli Bengaluru A.
Published: June 2008

✓Osteochondromas are the most common benign bone tumor. Although the metaphysial region of long bones is the usual site of these tumors, the vertebrae may be infrequently affected. The presentation may vary from typical compressive myelopathy to radiculopathy or radiculomyelopathy, depending on the site of involvement. The authors present 3 consecutive cases of cervical spine osteochondromas encountered over 3 years at their institution, each different in its site of involvement, presentation, and chosen treatment. The patient in Case 1 had the typical presentation and lesion site, and was treated with a conventional laminectomy. The patient in Case 2 presented with an extensive disease that required complex, staged surgery with spinal fusion and instrumentation. The patient in Case 3 presented with monoradiculopathy and had a facet joint osteochondroma that was successfully treated with a simple partial facetectomy, without laminectomy.
Malignant triton tumors of the spine
Authors: James Greg , Crocker Matthew , King Andrew , Bodi Istvan , Ibrahim Ahmed , Chitnavis Bhupal P.
Published: June 2008

✓Malignant triton tumors (MTTs) are malignant peripheral nerve sheath tumors with rhabdomyosarcomatous differentiation. Malignant triton tumors affecting the spine are rare but present special challenges to the neurosurgeon. The authors report on 2 new cases of spinal MTTs, and analyze the 8 previously reported cases found via database search.

The patients include a 15-year-old girl with thoracic MTT, and a 24-year-old man with lumbosacral MTT; both patients underwent radical resection with spinal stabilization. When these cases were combined with the literature results there was a male/female ratio of 6:4, and an age range of 15–67 years (median 37.5). Nine patients presented with symptoms related to the spinal cord, cauda equina, or nerve root compression. Four patients had undergone previous radiotherapy, and 2 had neurofibromatosis Type 1. Five cases of MTT were lumbosacral, 4 were thoracic, and 1 was cervical. Seven patients had intradural extension of tumor. All patients underwent some form of surgery, with 8 having total macroscopic excision. However, 6 patients required subsequent operations. In the 8 patients for which survival data was available, median time from diagnosis to death was 12 months (range 3–16).

Malignant triton tumors are rare but should be included in the differential diagnosis of spinal tumors, particularly in patients who have undergone previous radiotherapy or who have neurofibromatosis. The authors suggest roles for radical surgery and multidisciplinary management.
Adjacent-level vertebral body fractures after expandable cage reconstruction
Authors: Chou Dean , Lu Daniel C. , Weinstein Philip , Ames Christopher P.
Published: June 2008

✓Expandable cages are frequently used to reconstruct the anterior spinal column after a corpectomy. The forces that are used to expand these cages can be large, depending upon the mechanism of expansion. To the authors' knowledge, there have been no reports of adjacent-level vertebral body fracture after placement of expandable cages. The authors report 4 cases of adjacent-level vertebral body fractures after placement of expandable cages. This study found that the fracture pattern in the coronal plane was similar in all cases.
Acute renal insufficiency, supraventricular tachycardia, and confusion after recombinant human bone morphogenetic protein-2 implantation for lumbosacral spine fusion
Authors: Moshel Yaron A. , Hernandez Edgar I. , Kong Li , Liu Chuanju , Samadani Uzma
Published: June 2008

✓The authors report on a case of a patient who received recombinant human bone morphogenetic protein-2 (rhBMP-2) to augment spinal fusion for the first and third of 3 lumbosacral fusion surgeries. After receiving rhBMP-2 the first time, the patient became febrile and developed mild acute renal insufficiency and transient supraventricular tachycardia (SVT). The second operation was complicated only by perioperative fever. When the patient received rhBMP-2 again during the third operation, he developed fever, acute oliguric renal insufficiency, symptomatic SVT with hypoxemia, confusion, and joint pain. No clear cause of these problems was identified; however serum analysis revealed the presence of an antibody to rhBMP-2. The authors discuss potential mechanisms for the patient's putative reaction to rhBMP-2, as the findings from a literature review suggest this is the first such reaction to be reported.
A novel anterior technique for simultaneous single-stage anterior and posterior cervical release for fixed kyphosis
Authors: Wang Vincent Y. , Aryan Henry , Ames Christopher P.
Published: June 2008

✓The incidence rate of kyphosis of the cervical spine after a laminectomy can be as high as 20% after a multilevel laminectomy. The loss of the posterior tension band leads to increased load on the vertebral body and discs, leading to further degenerative changes and kyphotic deformities. The initial decompression of the spinal cord disappears as the cord is stretched over the anterior lesions. Muscle damage and facet degeneration from prior surgery contribute to additional pain, muscle spasm, and motion. Occasionally prior surgical fusion that fails to address the kyphosis or spontaneous fusion in a kyphotic position (observed more in laminectomies performed in the growing spine) can result in a challenging rigid deformity with anterior vertebral body and lateral mass facet fusion. For this fixed deformity, anterior and posterior release are often necessary for restoration of lordosis, which can result in the need for a 540° procedure. In this report the authors describe an anterior technique for simultaneous anterior and posterior lateral mass release. The vertebral artery is mobilized using this technique, allowing for its lateral retraction. The nerve roots are visualized and retracted superiorly and inferiorly. The lateral mass and facets can then be accessed anteriorly using an osteotome or drill for the release. The authors illustrate this technique in a patient who developed fixed scoliosis and kyphosis of the cervical spine after surgery for degenerative disc disease. To the authors' knowledge, this is the first report of this technique.
Cloning, Expression, Purification and Crystallization of the PR Domain of Human Retinoblastoma Protein-Binding Zinc Finger Protein 1 (RIZ1)
Authors: Sun Wanpeng , Geyer C. Ronald , Yang Jian
Published: June 2008

Through alternative promoter usage, human retinoblastoma protein-interacting zinc finger gene RIZ encodes two different protein products, RIZ1 and RIZ2, which have been identified to be a tumor suppressor and a proto-oncoprotein, respectively. Structurally, the two protein products share the same amino acid sequences except that RIZ2 lacks an N-terminal PR domain with methyltransferase activity. Previous studies have shown that over-expression of RIZ2 is usually associated with depressed RIZ1 expression in different human cancers. It is generally believed that RIZ1 and RIZ2 regulate normal cell division and function using a “Yin-Yang” fashion and the PR domain is responsible for the tumor suppressing activity of RIZ1. In order to better understand the biological functions of the PR domain by determining its three-dimensional crystal structure, we expressed, purified and crystallized a construct of the PR domain (amino acid residues 13-190) in this study. The maximum size of the needle-shaped crystals was approximately 0.20 x 0.01 x 0.01 mm.
A New Approach on Estimation of Solubility and n-Octanol/ Water Partition Coefficient for Organohalogen Compounds
Authors: Gao Shuo , Cao Chenzhong
Published: June 2008

The aqueous solubility (logW) and n-octanol/water partition coefficient (logPOW) are important properties for pharmacology, toxicology and medicinal chemistry. Based on an understanding of the dissolution process, the frontier orbital interaction model was suggested in the present paper to describe the solvent-solute interactions of organohalogen compounds and a general three-parameter model was proposed to predict the aqueous solubility and n-octanol/water partition coefficient for the organohalogen compounds containing nonhydrogen-binding interactions. The model has satisfactory prediction accuracy. Furthermore, every item in the model has a very explicit meaning, which should be helpful to understand the structure-solubility relationship and may be provide a new view on estimation of solubility.
Luminescent Conjugated Polymers: Illuminating the Dark Matters of Biology and Pathology
Authors: Nilsson K. Peter R. , Hammarström Per
Published: June 2008

Novel technologies for studying biological events are of great interest and luminescent conjugated polymers (LCPs), a material normally used in organic electronics, have proven useful for the detection of a wide range of disease‐related biological processes. The conformation‐sensitive optical properties of LCPs provide the ability to study the biochemical activity of biological events on the basis of a structure‐function relation, rather than a molecular basis. In this Research News article, the LCP technique and its usefulness for studying protein aggregation diseases are highlighted. We also discuss the much‐needed illuminating insights of the underlying pathological events regarding protein aggregation diseases. In addition, essential future basic research advances that relate to further development of LCPs as molecular probes are presented. We also confer the intriguing prospect of employing amyloid fibrils, that is, a symmetric stable nanomaterial normally associated with the dark side of horrific pathology, as a scaffold for functional polymer‐protein hybrid materials.
Angiotensin I‐converting enzyme I/D polymorphism and suicidal behaviors
Authors: Sparks D. Larry , Hunsaker John C. , Amouyel Philippe , Malafosse Alain , Bellivier Franck , Leboyer Marion , Courtet Philippe , Helbecque Nicole
Published: June 2008

Suicide is one of the ten most common causes of death in Western countries. It involves genetic vulnerability factors and is often associated with major depression. A Japanese team reported an association between the insertion allele of the angiotensin‐converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with completed suicide. The ACE I/D polymorphism was investigated in two independent case‐control studies, one involving 64 suicide completers and 90 controls who all underwent forensic investigations, the second one consisting of 588 suicide attempters and 639 controls. In the two population samples studied a statistically significant risk of suicidal behavior was observed for subjects bearing the DD genotype. These results suggest a possible role of the renin‐angiotensin system in suicidal behavior. © 2008 Wiley‐Liss, Inc.
Attending to the outcome of others: disadvantageous inequity aversion in male capuchin monkeys (Cebus apella)
Authors: Fletcher Grace E.
Published: June 2008

Brosnan and de Waal [Nature 425:297–299, 2003] reported that capuchin monkeys responded negatively to unequal reward distributions between themselves and another individual when comparing their own rewards with that of their partner. It was suggested that social emotions provided the underlying motivation for such behavior and that this inequity aversion is specific to the social domain. However, alternative hypotheses such as the “frustration effect” or the “food expectation hypothesis” may provide more parsimonious explanations for Brosnan and de Waal's [Nature 425:297–299] results, while others have argued that these findings are not congruent with the Fehr–Schmidt inequity aversion model cited by the authors. The claim that inequity aversion behavior is specific to the social domain has also been questioned, as primates also develop expectations about rewards in the absence of partners, and react negatively when those expectations are violated. In this study, a modified Dictator game was used to investigate whether capuchins would exhibit either disadvantageous inequity aversion behavior or reference‐dependent expectancy violation in social and nonsocial conditions, respectively. When given the choice between an equitable and an inequitable outcome, the subjects showed disadvantageous inequity aversion behavior, choosing the equitable outcome significantly more in the social condition. In the nonsocial condition, however, subjects did not show negative expectancy violation resulting from the formation of reference‐dependent expectations, choosing the equitable outcome at chance levels. These results suggest that capuchins attend to differential payoffs and that they are averse to inequity, which is disadvantageous to themselves. Am. J. Primatol. 70:901–905, 2008. © 2008 Wiley‐Liss, Inc.
Synthesis and structural investigations on R2 Sn(IV)‐D‐aldonic acid complexes (R = methyl; butyl). Their effect on a new toxicity test organism, Liza saliens (Osteichthyes, Mugilidae): a histological study
Authors: Bertazzi Nuccio , Casella Girolamo , D'Agati Paolo , Fiore Tiziana , Mansueto Caterina , Mansueto Valentina , Pellerito Claudia , Pellerito Lorenzo , Scopelliti Michelangelo
Published: May 2008

Eight R2Sn(IV)‐D‐aldonate complexes [(R = Me, Bu; D‐aldonate = D‐galactonate2− (Galn), D‐Gluconate2− (Glun), D‐Gulonate2− (Guln), D‐Ribonate2− (Ribn)], five of which are new derivatives, have been synthesized and structurally characterized both in solid and solution state by IR, 119Sn Mössbauer and 1H, 13C, 119Sn NMR spectroscopies, showing that ligands act as dianonic chelating agents. In solution phase, NMR data suggest that the bidentate chelation is attained by the O1 carboxylate and the vicinal O2 alkoxide atoms, which can be dynamically extended to a third binding site (O4) competing with O2. In Me2Sn(IV)‐D‐gluconate complex the occurrence of a self‐association process leading to a dimeric species was also observed. Histopathological studies on different organs of Liza saliens showed that the dibutyltin(IV)‐D‐aldonate complexes, although preserving the defense immunity system, exhibit a specific toxicity on some target cells and organs. The toxicity of such complexes has been compared with respect to the effects of a previous study with tributyltin(IV) chloride solutions. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation and characterization of electrospun, biodegradable membranes
Authors: Ren Jie , Liu Wanqiang , Zhu Jing , Gu Shuying
Published: May 2008

Nonwoven, biodegradable membranes fabricated by electrospinning have recently attracted a great deal of attention for biomedical applications. In this study, microporous, nonwoven membranes of poly(L‐lactide) and its copolymers and blends were fabricated through electrospinning. The structures and morphologies of the electrospun membranes were investigated with scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction. Different polymer membranes, incorporated with carmofur, were fabricated, and their drug release profiles were investigated. Scanning electron microscopy images showed that the fiber diameters were down to the nanometer range. The diameters and morphologies of thenanofibers depended on processing parameters such as the solution properties (concentration and polymer molecular weight), applied electric voltage, solution feeding rate, and needle diameter. Differential scanning calorimetry showed that the crystallinity of the electrospun membranes was lower than that of the cast film. For all the membranes incorporated with the drug, there was a burst release in the first 10 h of incubation in phosphate‐buffered saline at 37°C. Poly(glycolide‐co‐lactide) membranes showed faster and more complete drug release than poly(L‐lactide), and this could be attributed to its faster degradation. The incorporation of polylactide–poly(ethylene glycol) could shorten the drug release time. A combination of suitable degradable biomaterials with an appropriate electrospinning process could be useful in the fabrication of a new kind of membrane suitable for different biomedical applications such as tissue engineering and drug delivery. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Investigation of the interaction of CO2 with poly (L‐lactide), poly(DL‐lactide) and poly(ε‐caprolactone) using FTIR spectroscopy
Authors: Nalawade S. P. , Picchioni F. , Janssen L. P. B. M. , Grijpma D. W. , Feijen J.
Published: May 2008

Fourier transform infrared (FTIR) spectroscopy was used to reveal intermolecular interactions between carbon dioxide (CO2) and the carbonyl groups of poly(L‐lactide) (PLLA), poly(D,L‐lactide) (PDLLA), and poly(ε‐caprolactone) (PCL). After exposing polymer films to high pressure CO2, the wave number of the absorption maxima of the polymer carbonyl groups shifted to higher values. Also, due to the interaction between CO2 and the carbonyl groups of the polymers, a new broad peak in the bending mode region of CO2 appeared. To distinguish between polymer‐associated and nonassociated CO2, and to quantify these contributions, the bending mode peaks were deconvoluted. From these contributions, it was found that in the case of PCL more CO2 is interacting with the polymer carbonyl groups than in the case of PDLLA and PLLA. Under our experimental conditions, 40°C and pressures up to 8 MPa, a significant depression of the PCL melting temperature was observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Rheological properties of poly(ethylene glycol)/poly(N‐isopropylacrylamide‐co‐2‐acrylamido‐2‐methylpropanesulphonic acid) semi‐interpenetrating networks
Authors: Zhang Chi , Easteal Allan J.
Published: June 2008

For the increasing demands of multifunctional materials in applications such as drug delivery system, a pH‐ and temperature‐responsive polyelectrolyte copolymer gel system was studied using rheometry. Rheological properties, determined by plate–plate rheometry in oscillatory shear, of hydrogels formed by free radical initiated copolymerization of N‐isopropylacrylamide (NIPA) and 2‐acrylamido‐2‐methylpropanesulphonic acid (AMPS) in the presence of methylene bisacrylamide (MBAA) as crosslinker are compared with the properties of semi‐interpenetrating network (SIPN) polyelectrolyte gels made by incorporation of poly(ethylene glycol) with molar mass 6000 g mol−1 (PEG6000). Based on our systematic studies for this PEG/SIPN system, the effects of initiator and crosslinker concentration, relative proportions of comonomer units in the main chains, PEG6000 content and temperature on viscoelastic properties, unusual high storage moduli at small strain for the SIPN were discussed. The SIPN gel with characteristics of PEG molecules as well as pH and temperature responsiveness from AMPS and NIPA units has potential application in drug delivery system design. Ice‐like rheological behavior of the PEG/AMPS‐NIPA SIPN gels at low temperature was first time reported and water remains homogeneous without phase separation in PEG/AMPS‐NIPA SIPN hydrogels at low temperature may be considered as an ideal candidate for water storage material. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Investigation on thermoplastic co‐poly(ether‐ester) elastomer toughened poly(methylmethacrylate) blends
Authors: Poomalai P. , Varghese T. O. , Siddaramaiah
Published: June 2008

Blends of poly(methyl methacrylate) (PMMA) and copoly(ether‐ester) (COPE) elastomer have been prepared in different compositions namely, 95/5, 90/10, 85/15, and 80/20 wt % (PMMA/COPE), by melt mixing technique using twin screw extruder. The influence of COPE content on the mechanical properties especially impact strength, thermal behavior, and chemical resistance of PMMA have been investigated. The impact strength of the PMMA/COPE blends for all the compositions were found to be improved remarkably as compared to the virgin PMMA without affecting the other mechanical properties significantly. Various composite models, such as series model, parallel model, Halpin‐Tsai equation, and Kerner's model have been used to fit the experimental mechanical properties. The effect of chemical and thermal ageing on the performance of the PMMA/COPE blends was also studied. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Improving the efficiency of imprinting in poly(HEMA) for polyaromatic hydrocarbon using silver ions
Authors: Sreenivasan K.
Published: May 2008

Molecularly imprinted polymer for a typical polyaromatic hydrocarbon, naphthalene, was synthesized. Silver ions are incorporated during the synthesis and the equilibrium uptake of the template molecule (naphthalene) by the imprinted polymer was found to be many folds higher than the uptake of the molecule by the imprinted polymer prepared in the absence of the metal ions. The enhanced adsorption was attributed due to the improved interaction between the template molecules and the monomers which is reasoned to be induced by the silver ions. It appears that the adsorption capacity of molecules without having any functional groups could be increased by the methodology reported here. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Mechanism of Fibroblast‐Like Synoviocyte Apoptosis Induced by Recombinant Human Endostatin in Rats with Adjuvant Arthritis
Authors: Huang Xue‐Ying , Chen Fei‐Hu , Li Jun , Xia Li‐Juan , Liu Yong‐Jing , Zhang Xiao‐Ming , Yuan Feng‐Lai
Published: May 2008

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by pronounced synovial hyperplasia, in which there may be an imbalance between the growth and death of fibroblast‐like synoviocytes (FLS). The present study was undertaken to examine the effect of recombinant human endostatin (rhEndostatin) on FLS apoptosis in experimental RA. Adjuvant arthritis (AA) was induced in male Sprague Dawley (SD) rats. Using cultured AA FLS obtained from these rats, the apoptosis process was measured by terminal deoxyribonucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL) as well as Annexin V‐fluorescein isothiocyanate (FITC) and propidium iodide (PI) labeling methods. In addition, the expression levels of the Fas, c‐jun, NFκB, and caspase‐3 gene products in synovial tissues were quantified by quantitative real‐time polymerase chain reaction (qPCR) and/or Western blotting assays. Our data revealed that rhEndostatin induced apoptosis in AA FLS. The number and signal density of TUNEL‐positive cells were significantly increased in rats treated with rhEndostatin (2.5 mg/kg). The percentage of Annexin V‐FITC‐positive cells was 6.67% after treatment with rhEndostatin at 25 μg/mL for 48 hr, compared with only 3.32% among untreated control cells. There were significant increases in Fas mRNA, c‐jun mRNA, c‐Jun protein, and caspase‐3 (p20) protein in AA synovial tissues treated with rhEndostatin (2.5 mg/kg), whereas no significant difference in NFκB expression was detected between treated and untreated tissues. These findings indicate that rhEndostatin has a therapeutic effect on RA by inducing FLS apoptosis, which is strongly associated with increased expression of Fas, c‐jun, and caspase‐3, but not NFκB. Anat Rec, 291:1029–1037, 2008. © 2008 Wiley‐Liss, Inc.
Annual Morphological Cycles of Testis and Thumb Pad of the Male Frog (Rana ridibunda)
Authors: Kaptan Engin , Murathanoğlu Osman
Published: May 2008

In this study, Rana ridibunda was used as samples because of their wide use in Turkey. Male frogs were collected in the East Marmara region each month throughout 1 year. Frogs from every monthly collection were used to analyze structural components of the thumb pads and testes. Spermatogenetic activity of Rana ridibunda living in the East Marmara region was determined to be “potentially continuous” type. Generally, the increase in the number and the size of nuclei of Leydig cells was inversely proportional to the fluctuation of spermatogenetic activity. The lumen of the seminiferous tubules in testes contained, in addition to the spermatogenic cells, a Periodic‐acid Schiff‐positive granular material. The amount of this material varied throughout the year, and that finding suggested a function related to spermiation. The components of thumb pads exhibited structural changes with respect to the activities of Leydig cells. During the periods where the Leydig cells were active, mucus glands (also called breeding glands) of thumb pads were also developed. On the other hand, we observed mixed glands with unknown function, which as first reported by us, and were poison glands in the thumb pads. The results suggest structural changes in the thumb pads are linked to changes in the testes. Anat Rec, 291:1106‐1114, 2008. © 2008 Wiley‐Liss, Inc.
Polymorphs and Polymorphic Cocrystals of Temozolomide
Authors: Babu N. Jagadeesh , Reddy L. Sreenivas , Aitipamula Srinivasulu , Nangia Ashwini
Published: June 2008

Crystal polymorphism in the antitumor drug temozolomide (TMZ), cocrystals of TMZ with 4,4′‐bipyridine‐N,N′‐dioxide (BPNO), and solid‐state stability were studied. Apart from a known X‐ray crystal structure of TMZ (form 1), two new crystalline modifications, forms 2 and 3, were obtained during attempted cocrystallization with carbamazepine and 3‐hydroxypyridine‐N‐oxide. Conformers A and B of the drug molecule are stabilized by intramolecular amide NH⋅⋅⋅Nimidazole and NH⋅⋅⋅Ntetrazine interactions. The stable conformer A is present in forms 1 and 2, whereas both conformers crystallized in form 3. Preparation of polymorphic cocrystals I and II (TMZ⋅BPNO 1:0.5 and 2:1) were optimized by using solution crystallization and grinding methods. The metastable nature of polymorph 2 and cocrystal II is ascribed to unused hydrogen‐bond donors/acceptors in the crystal structure. The intramolecularly bonded amide N–H donor in the less stable structure makes additional intermolecular bonds with the tetrazine CO group and the imidazole N atom in stable polymorph 1 and cocrystal I, respectively. All available hydrogen‐bond donors and acceptors are used to make intermolecular hydrogen bonds in the stable crystalline form. Synthon polymorphism and crystal stability are discussed in terms of hydrogen‐bond reorganization.
Family‐based association testing of OCD‐associated SNPs of SLC1A1 in an autism sample
Authors: Brune Camille W. , Kim Soo‐Jeong , Hanna Gregory L. , Courchesne Eric , Lord Catherine , Leventhal Bennett L. , Cook Edwin H.
Published: May 2008

Reports identified the neuronal glutamate transporter gene, SLC1A1 (OMIM 133550, chromosome 9p24), as a positional and functional candidate gene for obsessive–compulsive disorder (OCD). The presence of obsessions and compulsions similar to OCD in autism, the identification of this region in a genome‐wide linkage analysis of individuals with autism spectrum disorders (ASDs), and the hypothesized role of glutamate in ASDs make SLC1A1 a candidate gene for ASD as well. To test for association between SLC1A1 and autism, we typed three single nucleotide polymorphisms (SNPs, rs301430, rs301979, rs301434) previously associated with OCD in 86 strictly defined trios with autism. Family‐Based Association Tests (FBAT) with additive and recessive models were used to check for association. Additionally, an rs301430–rs301979 haplotype identified for OCD was investigated. FBAT revealed nominally significant association between autism and one SNP under a recessive model. The G allele of rs301979 was undertransmitted (equivalent to overtransmission of the C allele under a dominant model) to individuals with autism (Z=−2.47, P=0.01). The G allele was also undertransmitted in the T–G haplotype under the recessive model (Z=−2.41, P=0.02). Both findings were also observed in the male‐only sample. However, they did not withstand correction for multiple comparisons.
Music and Physics: A Cultural, Interdisciplinary History
Authors: Jackson Myles W.
Published: June 2008

Musik und Physik: Eine kulturelle, interdisziplinäre Geschichte. Dieser Aufsatz untersucht den Austausch zwischen Physikern, Musikern, und Instrumentenmachern in Deutschland im 19. Jahrhundert. Er repräsentiert eine materielle Kulturgeschichte, die gleichzeitig eine interdisziplinäre Analyse darstellt. Vier konkrete Beispiele solchen Austausches werden diskutiert: das Verhältnis zwischen musikalischen Automaten und Virtuosi, die Zungenpfeife als ein musikalisches und wissenschaftliches Instrument, die Geschichte der Standardisierung des Kammertons, und die Versuche, musikalische Virtuosität zu bemessen. Dieser Aufsatz zeigt, wie Kulturgeschichten erstens den naturwissenschaftlichen Inhalt ernst nehmen können und sollen, und zweitens, wie solche Geschichten disziplinäre Geschichten verbessern können.
Colour change of chemiluminescence for base‐induced decomposition of dioxetane bearing a 4‐(4‐cyanophenyl)iminomethyl‐3‐hydroxyphenyl group
Authors: Watanabe Nobuko , Suga Naoki , Matsumoto Masakatsu
Published: May 2008

A bicyclic dioxetane 1 bearing a 4‐(4‐cyanophenyl)iminomethyl‐3‐hydroxyphenyl group was found to undergo base‐induced decomposition with the accompanying emission of light, the colour of which changed depending on the base used and its concentration. When 1 was triggered with tetrabutylammonium fluoride (TBAF), 1 displayed an emission of glowing orange light. On the other hand, on treatment with a high concentration of potassium t‐butoxide complexed with 18‐crown‐6 ether, 1 afforded a flash of blue light. The mechanistic study of this unprecedented phenomenon revealed that the emission of glowing orange light was due to the normal oxido anion of keto ester 11, whereas the emission of a flash of blue light was attributed to another species that was produced by addition of a nucleophile to an iminomethyl of unstable oxido anion of dioxetane 10. Copyright © 2008 John Wiley & Sons, Ltd.
Structural implications of mitochondrial dynamics
Authors: Bereiter‐Hahn Jürgen , Vöth Monika , Mai Sören , Jendrach Marina
Published: June 2008

Mitochondrial components are continuously distributed throughout the whole chondriome of a cell by fusion and fission. Thus, a single mitochondrion represents a transient fraction of the chondriome. Mitochondrial dynamics are responsible for intracellular distribution and reaction of mitochondria to functional requirements. Dynamics occur on different levels: overall morphology, inner membrane–matrix compartment, turnover and rearrangements of mitochondrial proteins and DNA. Electron micrographs of serial sections of human umbilical vein endothelial cells reveal perinuclear mitochondria of extreme length and with branches in those cells that also have short peripheral mitochondria. Interactions of mitochondria with cytoskeletal elements are revealed in cells treated with cytochalasin D to destroy actin fibrillar structures or after disassembling microtubule by nocodazole. In the latter case mitochondria not only become immobilized, they also acquire a multiple ring structure. In F‐actin‐disturbed cells, motility (shape changes in particular) is increased and the mitochondria become elongated. Mechanisms of how F‐actin might render mitochondria immobile may involve dynamin‐related protein 1 (DRP1) or interaction with anion channels. This may be responsible for the lack of mitochondrial motility in senescent cells. Fusion between mitochondria revealed local fluctuations of mitochondrial red fluorescent protein (mtRFP), indicating novel fast inner membrane reorganizations. Mitochondrial dynamics result from a complex interplay between the molecular organization of the inner membrane–matrix complex and cytoskeletal elements outside.
Solvent interactions with the Trp‐cage peptide in 35% ethanol–water
Authors: Neuman Robert C. , Gerig John T.
Published: May 2008

Intermolecular NOE experiments have been used to explore interactions of water and ethanol molecules in 35% ethanol/65% water (v/v) with the peptide Trp‐cage at temperatures from 5 to 25°C. Magnetic dipole–dipole cross‐relaxation terms σ and σ for interaction of solvent components with spins of the peptide suggest that ethanol molecules associate with backbone atoms for times of the order of nanoseconds at 5°C. Formation of peptide–ethanol complexes can also account for the larger‐than‐expected values of cross‐relaxation terms at higher temperatures. Hydrocarbon side chains of the peptide do not appear to experience such interactions with ethanol. Cross relaxation resulting from water–peptide interactions are consistent with long‐lived water interactions with the backbone atoms. Water cross relaxation with nonpolar side chains of the peptide (Leu2, Ile4, Leu7, and proline residues) are only those expected for bulk solvent. However, long‐lived association of both water and ethanol with the polar side chains of Tyr3 and Trp6 is indicated by the data. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 862–872, 2008.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Self‐assembling peptides: Sequence, secondary structure in solution and film formation
Authors: Gambaretto Roberta , Tonin Lorenzo , Di Bello Carlo , Dettin Monica
Published: June 2008

Peptides of alternating charge and hydrophobic amino acids have a tendency to adopt unusually stable β‐sheet structures that can form insoluble macroscopic aggregates under physiological conditions. In this study, analogues of a well‐known self‐assembling peptide, characterized by the same polar/nonpolar periodicity but with different residues, were designed to study the relationship between sequence, conformation in solution and film‐forming capacity in saline solution. Peptide conformation, evaluated by circular dichroism, correlated with film forming capacity observed by inverted optical microscopy after addition of saline solution and subsequent drying. We found that polar/nonpolar periodicity of several analogues is not criterion enough to induce β‐sheet and thus film formation and that conformations different from β‐sheet also allow self‐assemblage. Furthermore, addition of the short adhesive sequence RGD to a known self‐assembling sequence was shown to not prevent the self‐assembling process. This finding might prove useful for the design of biomimetic scaffolds. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 906–915, 2008.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Application of high‐speed counter‐current chromatography for the isolation of antiviral eremophilenolides from Ligularia atroviolacea
Authors: Shi Shu‐Yun , Zhou Hong‐Hao , Huang Ke‐Long , Li Hai‐Bo , Liu Su‐Qin , Zhao Yu
Published: June 2008

Ligularia is mainly distributed in the western regions of China. Most of the species have been traditionally used in folk medicine for the treatment of hepatitis B, asthma, hemoptysis and pulmonary tuberculosis. In our continuation of research on antiviral components from traditional Chinese medicine, Ligularia atroviolacea was tested for inhibitory effects on hepatitis B virus (HBV). A bioassay‐guided phytochemical examination of L. atroviolacea disclosed that its ethyl acetate extract, which was made up of two eremophilenolides, showed suppressive activity on the expression of HBV surface antigen (HBsAg) in the HepG2.2.15 cell line. Then a simple and effective preparative high‐speed counter‐current chromatography method was successfully developed for the isolation and purification of two main active metabolites, 8β‐hydroxyeremophil‐3,7(11)‐dien‐12,8α;15,6α‐diolide and 8β‐methoxyeremophil‐3,7(11)‐dien‐12,8α;15,6α‐diolide from the ethyl acetate extract of L. atroviolacea by a one‐step separation using a two‐phase solvent system composed of light petroleum (60–90°C)–ethyl acetate–methanol–water (9:1:8:2, v/v/v). The chemical structures of the two eremophilenolides were identified by ESI‐MS, 1H‐NMR and 13C‐NMR analysis. The anti‐HBV activity of the two purified compounds was measured; both of them showed suppressive activity on the expression of HBsAg in the HepG2.2.15 cell line. The results support the continued and expanded exploitation and utilization of L. atroviolacea. Copyright © 2008 John Wiley & Sons, Ltd.
A sensitive method for determination of salvianolic acid A in rat plasma using liquid chromatography/tandem mass spectrometry
Authors: Pei Lixia , Bao Yuanwu , Wang Haidi , Yang Fan , Xu Bei , Wang Shoubao , Yang Xiuying , Du Guanhua
Published: May 2008

Salvianolic acid A (SAA), a major effective constituent of Salvia miltiorrhizas, is widely used in traditional Chinese medicine. A sensitive rapid analytical method was established and validated for SAA in rat plasma, which was further applied to assess the pharmacokinetics of SAA in rats receiving a single oral dose of SAA. The method used liquid chromatography tandem mass spectrometry in multiple reaction monitoring mode with chloramphenicol as the internal standard. A simple liquid–liquid extraction based on ethyl acetate was employed. The combination of a simple sample cleanup and short chromatographic run time (3 min) increased the throughput of the method substantially. The method was validated over the range 1.4–1000 ng/mL with a correlation coefficient >0.99. The lower limit of quantification was 1.4 ng/mL for SAA in plasma. Intra‐ and inter‐day accuracies for SAA were 95–113 and 98–107%, and the inter‐day precision was less than 12%. This method is more sensitive and faster than previous methods. After a single oral dose of 100 mg/kg of SAA, the mean peak plasma concentration (Cmax) of SAA was 318 ng/mL at 0.5 h, the area under the plasma concentration–time curve (AUC0–12 h) was 698 ± 129 ng·h/mL, and the elimination half‐life (T1/2) was 3.29 h. Copyright © 2008 John Wiley & Sons, Ltd.
N‐Tosyloxycarbamates as Reagents in Rhodium‐Catalyzed CH Amination Reactions
Authors: Huard Kim , Lebel Hélène
Published: June 2008

Metal nitrenes for use in CH insertion reactions were obtained from N‐tosyloxycarbamates in the presence of an inorganic base and a rhodium(II) dimer complex catalyst. The CH amination reaction proceeds smoothly, and the potassium tosylate that forms as a byproduct is easily removed by filtration or an aqueous workup. This new methodology allows the amination of ethereal, benzylic, tertiary, secondary, and even primary CH bonds. The intramolecular reaction provides an interesting route to various substituted oxazolidinones, whereas the intermolecular reaction gives trichloroethoxycarbonyl‐protected amines that can be isolated with moderate to excellent yields and that cleave easily to produce the corresponding free amine. The development, scope, and limitations of the reactions are discussed herein. Isotopic effects and the electronic nature of the transition state are used to discuss the mechanism of the reaction.
Azacalix[6]arene Hexamethyl Ether: Synthesis, Structure, and Selective Uptake of Carbon Dioxide in the Solid State
Authors: Tsue Hirohito , Ishibashi Koichi , Tokita Satoshi , Takahashi Hiroki , Matsui Kazuhiro , Tamura Rui
Published: May 2008

To investigate dynamic solid‐state complexation hitherto unexplored in nitrogen‐bridged calixarene analogues, azacalix[6]arene hexamethyl ether has been prepared in three steps by applying a 5+1 fragment‐coupling approach by using a Buchwald– Hartwig aryl amination reaction with the aid of our previously devised temporal N‐silylation protocol. X‐ray crystallographic analysis and NMR spectroscopic measurements have revealed that the azacalix[6]arene is well endowed with hydrogen‐bonding ability, by which both the molecular and crystal structures are controlled. The azacalix[6]arene is conformationally flexible in solution on the NMR time scale, whereas it adopts a definite 1,2,3‐alternate conformation with S2 symmetry in the solid state as a result of intramolecular bifurcated hydrogen‐bonding interactions. In the crystal, molecules of the azacalix[6]arene are mutually interacted by intermolecular hydrogen bonds to establish one‐dimensional hexane‐filled nanochannel crystal architecture. Although the single crystal was broken after desolvation, the resultant polycrystalline powder material was capable of selectively adsorbing CO2 among the four main gaseous components of the atmosphere. In contrast, carbocyclic p‐tert‐butylcalix[6]arene hexamethyl ether, the crystal structure of which was also elucidated for the first time in the present study, gave rise to almost no uptake of CO2. Additional solid–gas adsorption experiments for another three gases, such as N2, O2, and Ar, suggested that quadrupole/induced‐dipole interactions and/or hydrogen‐bonding interactions played an important role in permitting the observed selective uptake of CO2 by this new azacalix[6]arene in the solid state.
Classical Reagents: New Surprises in Palladium‐Catalyzed CC Coupling Reactions
Authors: Lindhardt Anders T. , Skrydstrup Troels
Published: May 2008

From investigations on a relatively simple concept to identify conditions for promoting Mizoroki–Heck reactions with vinyl tosylates and phosphates, two serendipitous discoveries were made concerning new properties of palladium as a catalyst. In the first case, β‐hydride eliminations well known for alkyl metal complexes were found to be equally feasible with alkenyl metal compounds. And secondly, conditions were found for promoting intermolecular ene–yne couplings via a PdII–H intermediate. This coupling reactions represents an atom economical Mizoroki–Heck type reaction.
A General Organocatalytic Enantioselective Malonate Addition to α,β‐Unsaturated Enones
Authors: Wascholowski Veit , Knudsen Kristian Rahbek , Mitchell Claire E. T. , Ley Steven V.
Published: June 2008

A general enantioselective organocatalytic conjugate addition procedure of a variety of malonates to α,β‐unsaturated enone systems is presented. The reaction is efficiently catalysed by the pyrrolidinyl tetrazole catalyst 1. Cyclic, acyclic and aromatic enones can be used and the reaction with ethyl malonates 3 b provides the Michael addition products in high yields with good to excellent enantioselectivities. Since only 1.5 equivalents of malonate are used as a reagent, the reaction is readily scaled and practical to operate. Furthermore, the malonate addition products can be easily mono decarboxylated without loss in enantiomeric excess by enzymatic or sodium hydroxide mediated methods.
ChemInform Abstract: Structure and Properties of a New Family of Nearly Equiatomic Rare‐Earth Metal‐Tin‐Germanides RESn1+xGe1‐x (RE: Y, Gd—Tm): An Unusual Example of Site Preferences Between Elements for the Same Group.
Authors: Tobash Paul H. , Meyers John J. , DiFilippo Gary , Bobev Svilen , Ronning Filip , Thompson Joe D. , Sarrao John L.
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Rapid Co‐Precipitation and Non‐Isothermal Decomposition Kinetics of New Binary Mn0.5Co0.5 (H2PO4)2×2H2O.
Authors: Boonchom Banjong , Youngme Sujittra , Danvirutai Chanaiporn
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ruthenium‐Catalyzed Cross‐Coupling of 7‐Azabenzonorbornadienes with Alkynes. An Entry to 3a,9b‐Dihydrobenzo[g]indoles.
Authors: Tenaglia Alphonse , Marc Sylvain
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient DMF‐Promoted Solventless Hydrolysis of Epoxides with Equimolar Amount of H2O, Affording 1,2‐Diols.
Authors: Jiang Jia‐Li , Xiu Zhou , Hua Ruimao
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Unexpectedly High Activity of Zn(OTf)2×6H2O in Catalytic Friedel—Crafts Acylation Reaction.
Authors: He Fei , Wu Huayue , Chen Jiuxi , Su Weike
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: MW‐Assisted Er(OTf)3‐Catalyzed Mild Cleavage of Isopropylidene Acetals in Tricky Substrates.
Authors: Procopio Antonio , Gaspari Marco , Nardi Monica , Oliverio Manuela , Romeo Roberto
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient Transformation of Azides to Primary Amines Using the Mild and Easily Accessible CeCl3×7H2O/NaI System.
Authors: Bartoli Giuseppe , Di Antonio Giustino , Giovannini Riccardo , Giuli Sandra , Lanari Silvia , Paoletti Melissa , Marcantoni Enrico
Published: June 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.