bluuebunny/crossref_metadata_2025 huggingface dataset:
Lumbar spinous process—splitting laminectomy for lumbar canal stenosis
Authors: Watanabe Kota , Hosoya Toshihiko , Shiraishi Tateru , Matsumoto Morio , Chiba Kazuhiro , Toyama Yoshiaki
Published: May 2009

✓ In conventional laminectomy for lumbar canal stenosis (LCS), intraoperative damage of posterior supporting structures can lead to irreversible atrophy of paraspinal muscles. In 2001, the authors developed a new procedure for lumbar laminectomy, the lumbar spinous process—splitting laminectomy (LSPSL).

In this new procedure, the spinous process is split longitudinally in the middle and then divided at its base from the posterior arch, leaving the bilateral paraspinal muscles attached to the lateral aspects. Ample working space for laminectomy is obtained by retracting the split spinous process laterally together with its attached paraspinal muscles. After successfully decompressing nerve tissues, each half of the split spinous process is reapproximated using a strong suture. Thus, the supra- and interspinous ligaments are preserved, as is the spinous process, and damage to the paraspinal muscles is minimal.

Eighteen patients with LCS underwent surgery in which this new technique was used. Twenty patients in whom conventional laminectomy was undertaken were chosen as controls. At 2 years, the clinical outcomes (as determined using the Japanese Orthopaedic Association [JOA] scores and recovery rate) and the rate of measured magnetic resonance imaging—documented paravertebral muscle atrophy were evaluated and compared between the two groups. The mean JOA score recovery rates were 67.6 and 59.2%, respectively, for patients treated with LSPSL and conventional laminectomy; the mean rates of paravertebral muscle atrophy were 5.3 and 23.9%, respectively (p = 0.0005).

Preservation of posterior supporting structures and satisfactory recovery rate after 2 years indicated that this technique can be a useful alternative to conventional decompression surgery for lumbar canal stenosis.
Assessment of adjacent-segment disease in patients treated with cervical fusion or arthroplasty: a prospective 2-year study
Authors: Robertson James T. , Papadopoulos Stephen M. , Traynelis Vincent C.
Published: May 2009

Object. The authors compared the incidence of radiologically documented changes and symptomatic adjacent-level cervical disc disease after single-level discectomy and subsequent cervical fusion or arthroplasty in two independent prospective clinical studies.

Methods. The patients were treated with the Affinity Anterior Cervical Cage System or the Bryan Artificial Cervical Disc. In each study the patients were required to undergo serial cervical radiography preoperatively and 24 months postoperatively, as well as serial clinical evaluations including documentation of adverse events, neurological status, and results of the 36-item Short Form Health Survey. All serial radiographs were reviewed prior to evaluating the clinical symptoms for development of increasing or new adjacent degenerative disc disease (DDD). Subsequently, the clinical data were analyzed. For various reasons of exclusion, the cases analyzed in the Bryan disc—treated cohort consisted of 74 patients and in the Affinity system—treated cohort there were 158 patients. New anterior osteophyte formation or enlargement, increased narrowing of an interspace, new DDD, and calcification of the anterior longitudinal ligament were the radiological findings indicative of adjacent-level disease. Fusion was associated with a significant increase in x-ray film—based changes of adjacent-disc disease (p = 0.009, odds ratio [OR] 2.44). In the cage fusion series, the incidence of symptomatic adjacent-level DDD was statistically greater than that in the group treated with the artificial disc (p = 0.018), and the patients required a statistically greater number of medical treatments related to episodic symptoms of neck, shoulder, and arm pain attributed to new disc disease (p = 0.001, OR 35.8).

Conclusions. In comparing these prospective studies the authors demonstrated that maintaining motion rather than fusion will prevent symptomatic adjacent-disc disease and will decrease adjacent-level radiological indicators of disease at a 24-month postoperative interval.
Computerized tomography—guided kryorhizotomy in 76 patients with lumbar facet joint syndrome
Authors: Staender Marko , Maerz Ulrich , Tonn Jörg Christian , Steude Ulrich
Published: May 2009

Object.The authors prospectively evaluated the therapeutic effect of computerized tomography (CT)—guided kryorhizotomy in the treatment of patients with lumbar facet joint syndrome (LFJS) and assessed prognostic factors that predict this effect.

Methods.Between February 2001 and March 2004, CT-guided kryorhizotomy of facet joints was performed in 76 patients with LFJS. A diagnosis was established after three positive CT-guided medial nerve branch blocks. Outcome was determined by evaluating the results of a standardized questionnaire, including visual analog scale (VAS) score, use of medication, ability to work, and physical conditions. Measurement was performed before treatment and repeated postoperatively at 3 days, 3 months, and every 6 months thereafter. On September 2004 all patients underwent clinical reevaluation.

The median follow-up period was 22.5 months (range 6–43 months); the median interval to pain reduction was 6 months (range 0.1–31 months) after the first kryorhizotomy. The mean VAS pain score was 6.7 preoperatively and 2.9, 3.2, and 3.4 at 3 days, 3 months, and 6 months postoperatively, respectively. In 40% of patients pain was reduced for 12 months or longer. In patients in whom there was no prior surgical treatment of the relevant spinal segment, the duration of pain relief was significantly longer than in patients who had previously undergone surgery (p < 0.03). Eighteen patients underwent a second, seven a third, and one a fourth kryorhizotomy. No patient reported any side effect. The use of CT guidance guarantees an exact needle-tip position control and documentation for repeated procedures.

Conclusions.Computerized tomography—guided kryorhizotomy is a minimally invasive and repeatable treatment that yields good long-term results in patients with LFJS.
Biomechanical analysis of a newly designed bioabsorbable anterior cervical plate
Authors: Ames Christopher P. , Acosta Frank L. , Chamberlain Robert H. , Larios Adolfo Espinoza , Crawford Neil R.
Published: May 2009

Object. The authors present a biomechanical analysis of a newly designed bioabsorbable anterior cervical plate (ACP) for the treatment of one-level cervical degenerative disc disease. They studied anterior cervical discectomy and fusion (ACDF) in a human cadaveric model, comparing the stability of the cervical spine after placement of the bioabsorbable fusion plate, a bioabsorbable mesh, and a more traditional metallic ACP.

Methods. Seven human cadaveric specimens underwent a C6–7 fibular graft—assisted ACDF placement. A one-level resorbable ACP was then placed and secured with bioabsorbable screws. Flexibility testing was performed on both intact and instrumented specimens using a servohydraulic system to create flexion—extension, lateral bending, and axial rotation motions. After data analysis, three parameters were calculated: angular range of motion, lax zone, and stiff zone. The results were compared with those obtained in a previous study of a resorbable fusion mesh and with those acquired using metallic fusion ACPs. For all parameters studied, the resorbable plate consistently conferred greater stability than the resorbable mesh. Moreover, it offered comparable stability with that of metallic fusion ACPs.

Conclusions. Bioabsorbable plates provide better stability than resorbable mesh. Although the results of this study do not necessarily indicate that a resorbable plate confers equivalent stability to a metal plate, the resorbable ACP certainly yielded better results than the resorbable mesh. Bioabsorbable fusion ACPs should therefore be considered as alternatives to metal plates when a graft containment device is required.
Gowers intrasyringal hemorrhage
Authors: Hamlat Abderrahmane , Adn Mahmoudreza , Yahia Mourad Ben , Morandi Xavier , Brassier Gilles , Guegan Yvon
Published: May 2009

✓ The concept of hemorrhage in a preexisting syringomyelic cavity was first described by Gowers in 1904. Since its first description only 13 cases have been reported. The aims of this report are to describe a new case, bring this entity to wider attention, and summarize the existing literature on the subject.

This 36-year-old woman presented with progressive gait disturbance and unsteadiness. Physical examination revealed incomplete quadriparesis, predominantly on the left side, and hypesthesia below C-7. Magnetic resonance imaging revealed hematomyelia characterized by a heterogeneous hyperintense signal within the central cervical cord. A liquefied well-limited hematoma was evacuated. The postoperative course was uneventful; a near-complete recovery was observed at the 7-year follow-up examination.

Most cases of intrasyringal hemorrhage (ISH) have occurred in syringomyelic cavities associated with scoliosis or Chiari malformation Type I. Although there is no specific clinical picture associated with this entity, it can be characterized by three neurological forms: 1) sudden onset or rapid development of signs and symptoms, 2) acute worsening of symptoms that may improve but leaving greater neurological dysfunction than before the previous episode, and 3) ISH may initiate progressive deterioration in a patient with known syringomyelia.

Intrasyringal bleeding is most probably caused by a sudden dilation of the syringomyelic cavity, which may provoke rupture of the intrasyringal vessels by an acute distension of the accompanying strands.

Magnetic resonance imaging is the most accurate diagnostic modality, and recognition of ISH can lead to early, safe, and efficient surgical treatment.
Spinal hemangioblastoma containing metastatic renal cell carcinoma in von Hippel—Lindau disease
Authors: Altinoz Meric A. , Santaguida Carlo , Guiot Marie-Christine , Del Maestro Rolando F.
Published: May 2009

✓ The authors describe the case of a patient with von Hippel—Lindau (VHL) disease in which a spinal hemangioblastoma contained metastatic renal cell carcinoma (RCC). The literature on tumor-to-tumor metastasis associated with VHL disease of the central nervous system (CNS) is reviewed.

Midthoracic back pain developed in this 43-year-old man with a left-sided radicular component 2 years after he underwent resection of a left RCC. Radiological findings demonstrated a T6–7 intradural intramedullary lesion. A T5–8 laminectomy and gross-total resection of the spinal cord mass were performed. Light and electron microscopic examination showed features of hemangioblastoma, which contained metastatic foci of RCC. Genetic analysis demonstrated the presence of a deleting mutation in the first exon (nt. 394–406) of the VHL locus, truncating 16 amino acids (N61–77) from the first beta sheet in the VHL protein. A review of the literature revealed that RCC-to-CNS hemangioblastoma is the second most common donor—recipient tumor association among the tumor-to-tumor metastases.
Spinal pelvic reconstruction after total sacrectomy for en bloc resection of a giant sacral chordoma
Authors: Gallia Gary L. , Haque Raqeeb , Garonzik Ira , Witham Timothy F. , Khavkin Yevgeniy A. , Wolinsky Jean Paul , Suk Ian , Gokaslan Ziya L.
Published: May 2009

✓ Although radical resection prolongs the disease-free survival period, surgical management of primary sacral tumors is challenging because of their location and often large size. Moreover, in cases of lesions for which a radical resection necessitates total sacrectomy, reconstruction is required. The authors have previously described a modified Galveston technique in which a liaison between the spine and pelvis is achieved using lumbar pedicle screws and Galveston rods embedded into the ilia; additionally, a transiliac bar reestablishes the pelvic ring. Although this reconstruction technique achieves stabilization, several biomechanical limitations exist. In the present report the authors present the case of a patient who underwent spinal pelvic reconstruction after a total sacrectomy was performed to remove a giant sacral chordoma. They describe a novel spinal pelvic reconstruction technique that addresses some of the biomechanical limitations.
Atlantoaxial Screw Fixation
Authors: Neo Masashi
Published: May 2009

Object. In this, the first of two articles regarding C1–2 transarticular screw fixation, the authors assessed the rate of fusion, surgery-related complications, and lessons learned after C1–2 transarticular screw fixation in an adult patient series.

Methods. The authors retrospectively reviewed 191 consecutive patients (107 women and 84 men; mean age 49.7 years, range 17–90 years) in whom at least one C1–2 transarticular screw was placed. Overall 353 transarticular screws were placed for trauma (85 patients), rheumatoid arthritis (63 patients), congenital anomaly (26 patients), os odontoideum (four patients), neoplasm (eight patients), and chronic cervical instability (five patients). Among these, 67 transarticular screws were placed in 36 patients as part of an occipitocervical construct. Seventeen patients had undergone 24 posterior C1–2 fusion attempts prior to referral. The mean follow-up period was 15.2 months (range 0.1–106.3 months).

Fusion was achieved in 98% of cases followed to commencement of fusion or for at least 24 months. The mean duration until fusion was 9.5 months (range 3–48 months). Complications occurred in 32 patients. Most were minor; however, five patients suffered vertebral artery (VA) injury. One bilateral VA injury resulted in patient death. The others did not result in any permanent neurological sequelae.

Conclusions. Based on this series, the authors have learned important lessons that can improve outcomes and safety. These include techniques to improve screw-related patient positioning, development of optimal instrumentation, improved screw materials and design, and defining the role for stereotactic navigation. Atlantoaxial transarticular screw fixation is highly effective in achieving fusion, and the complication rate is low when performed by properly trained surgeons.
Recent Developments in the Chemistry of Deoxyribonucleic Acid (DNA) Intercalators: Principles, Design, Synthesis, Applications and Trends
Authors: Neto Brenno  A. D. , Lapis Alexandre  A. M.
Published: May 2009

In the present overview, we describe the bases of intercalation of small molecules (cationic and polar neutral compounds) in DNA. We briefly describe the importance of DNA structure and principles of intercalation. Selected syntheses, possibilities and applications are shown to exemplify the importance, drawbacks and challenges in this pertinent, new, and exciting research area. Additionally, some clinical applications (molecular processes, cancer therapy and others) and trends are described.
Synthesis, Characterization, Crystal Structure and Antibacterial Activities of Transition Metal(II) Complexes of the Schiff Base 2-[(4-Methylphenylimino)methyl]-6-methoxyphenol
Authors: Yu Yu-Ye , Xian Hui-Duo , Liu Jian-Feng , Zhao Guo-Liang
Published: May 2009

Five transition metal(II) complexes, [ML2Cl2] 1~5, were synthesized from the reaction of MCl2·nH2O (M = Mn, Co, Ni, Cu, Cd) and the Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (C15H15NO2, L), obtained by condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. They were characterized by elemental analysis, molar conductance, FT-IR spectra, thermal analysis. The structure of complex 1 was determined by single-crystal X-ray diffraction. Its crystal structure is of monoclinic system, space group P21/c with a = 9.0111(18) Å, b = 11.222(2) Å, c =28.130 (6) Å, α = 90 º, β = 92.29(3) º, γ = 90 º, V = 2867.6(10) Å3, Z = 4. The Mn atom is six-coordinate and displays distorted octahedral geometry.The Schiff base ligand and its complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia coli, Staphylococcus aureus and Bacillus subtilis. It has been found that the complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.
The Reaction of Diethyl Bromomalonate with p-tert-Butylthia-calix[4]arene: An Approach to Asymmetrical Derivatives
Authors: Omran Omran Abdellah
Published: May 2009

New dissymmetric and asymmetric p-tert-butylthiacalix[4]arene derivatives were prepared as a result of the reaction of p-tert-butylthiacalix[4]arene with diethyl bromomalonate in the presence of different alkali metals (Cs, K and Na) in refluxing acetone for 7 days. The structures of the prepared compounds were investigated by IR, 1H-NMR and MALDI-TOF mass spectroscopy.
A Real-Time Spectroscopic Sensor for Monitoring Laser Welding Processes
Authors: Sibillano Teresa , Ancona Antonio , Berardi Vincenzo , Lugarà Pietro Mario
Published: May 2009

In this paper we report on the development of a sensor for real time monitoring of laser welding processes based on spectroscopic techniques. The system is based on the acquisition of the optical spectra emitted from the laser generated plasma plume and their use to implement an on-line algorithm for both the calculation of the plasma electron temperature and the analysis of the correlations between selected spectral lines. The sensor has been patented and it is currently available on the market.
Intelligent Foreign Particle Inspection Machine for Injection Liquid Examination Based on Modified Pulse-Coupled Neural Networks
Authors: Ge Ji , Wang YaoNan , Zhou BoWen , Zhang Hui
Published: May 2009

A biologically inspired spiking neural network model, called pulse-coupled neural networks (PCNN), has been applied in an automatic inspection machine to detect visible foreign particles intermingled in glucose or sodium chloride injection liquids. Proper mechanisms and improved spin/stop techniques are proposed to avoid the appearance of air bubbles, which increases the algorithms’ complexity. Modified PCNN is adopted to segment the difference images, judging the existence of foreign particles according to the continuity and smoothness properties of their moving traces. Preliminarily experimental results indicate that the inspection machine can detect the visible foreign particles effectively and the detection speed, accuracy and correct detection rate also satisfying the needs of medicine preparation.
Managing Toxicities and Optimal Dosing of Targeted Drugs in Advanced Kidney Cancer
Authors: Seruga B. , Gan H. K. , Knox J. J.
Published: May 2009

The toxicities of new, targeted drugs may diminish their effectiveness in advanced kidney cancer if those toxicities are not recognized and properly addressed early in patient treatment. Most of the drug-related toxicities in advanced kidney cancer are manageable with supportive care, obviating a need for long interruptions, dose reductions, or permanent discontinuation of the treatment.
State-of-the-Art Treatment of Metastatic Renal Cell Carcinoma
Authors: Heng D. Y. C. , Kollmannsberger C.
Published: May 2009

Targeted therapy has greatly changed the way in which metastatic renal cell carcinoma (RCC) is treated. Agents that inhibit the vascular endothelial growth factor and mammalian target of rapamycin pathways that otherwise lead to angiogenesis have now become the standard of care. Much research into the sequence and combination of these agents is ongoing, and new anti-angiogenic agents are being developed. This overview covers the standard treatment of metastatic RCC with targeted therapy, immunotherapy, and surgery. Future directions and ongoing clinical trials are also discussed.
Natural History and Management of Small Renal Masses
Authors: Youssif T. Abou , Tanguay S.
Published: May 2009

The recent stage migration observed for renal tumours is contributing to a significant increase in the diagnosis of small renal masses. This evolution has led to a significant change in the approach to renal masses. New options such as observation or energy ablation are gaining popularity in a subset of this patient population. In addition, the observed changes directly contribute to the increased use of nephron-sparing surgery. A better understanding of the various characteristics of these masses will allow for a better understanding of the natural history of these masses and for selection of the optimal therapeutic approach.
Role of Cytokine Therapy for Renal Cell Carcinoma in the Era of Targeted Agents
Authors: Koneru R. , Hotte S. J.
Published: May 2009

Starting in the late 1980s, cytokines were considered the mainstay of treatment for locally advanced or metastatic renal cell carcinoma (RCC) because of a lack of improved survival with either chemotherapy or hormonal therapy alone. The cytokine agents interferon alfa (IFNα) and interleukin-2 (IL-2) have been the most evaluated, but a low overall response rate and a marginal survival advantage, coupled with significant toxicity, make these therapies less than ideal. Although complete tumour responses have occasionally been seen with high-dose IL-2, this therapy is associated with significant morbidity and mortality, and its approval has been based on limited nonrandomized evidence. Newer anti-angiogenesis agents have been evaluated as single agents and in combination with INFα, and these are now considered the standard of care for most patients with RCC. However, cytokines may still occasionally be recommended when angiogenesis inhibitors are not available or are contraindicated. In the present paper, we discuss the evidence for the use of cytokine therapy in the setting of pre– and post–targeted therapy for RCC.
Inhibition of mtor in Kidney Cancer
Authors: Kapoor A.
Published: May 2009

The mammalian target of rapamycin (mTOR) has been shown to be an important target mechanism in the treatment of renal cell carcinoma (RCC). In first-line treatment for patients with disease having poor prognostic features, temsirolimus, an mTOR inhibitor approved for treatment of advanced RCC, has demonstrated benefit over interferon alfa in both overall and progression-free survival. Everolimus, a second mTOR inhibitor that has showed activity in RCC, led to improved progression-free survival in a comparison with placebo in patients whose RCC progressed after treatment with vascular endothelial growth factor receptor tyrosine kinase inhibitors (sunitinib, sorafenib, or both). There is now compelling clinical evidence for the effectiveness of targeting mTOR in the treatment of RCC.
Sorafenib in the Management of Metastatic Renal Cell Carcinoma
Authors: Guevremont C. , Jeldres C. , Perrotte P. , Karakiewicz P. I.
Published: May 2009

Purpose: Sorafenib represents one of the two standards of care for patients with metastatic renal cell carcinoma (mRCC). In the present review, we provide information regarding the use of sorafenib in first and second lines. We also describe results for dose escalation strategies. Finally, we provide data addressing the efficacy of sorafenib in patients with mRCC of non-clear-cell histology. Recent Findings: Sorafenib is a valid first-line agent. Sorafenib response rates and toxicity are not affected by patient age or site of metastasis. The sequence of first-line sorafenib followed by second-line sunitinib resulted in a longer duration of response than did the opposite sequence. Sorafenib efficacy in first-line therapy can be potentiated by co-administration of low-dose interferon. Moreover, in first-line therapy, impressive response rates were recorded when the dose of sorafenib was escalated beyond the standard 400 mg twice daily. Similarly impressive response rates were observed with dose escalation in second-line therapy. It is notable that dose escalation after failure of standard sorafenib dose also prolongs progression-free survival. Finally, the efficacy of sorafenib is not limited to clear-cell histology, but also applies to chromophobe and papillary mRCC variants. Summary: Sorafenib is a highly effective and well-tolerated agent for first- and second-line patients with clear-cell, chromophobe, or papillary mRCC variants.
Review of Guidelines on the Treatment of Metastatic Renal Cell Carcinoma
Authors: Soulières D.
Published: May 2009

Guidelines on the management of metastatic renal cell carcinoma (RCC) have emerged over the last couple of years because of the introduction of effective new targeted therapies. However, current guidelines are not always contemporary because of older data whose relevance is unclear in the context of the new therapies. Moreover, many of the relevant trials were interrupted prematurely because of significant advantages in progression-free survival. These circumstances sometimes make interpretation of the data and characterization of subgroups rather difficult. The current paper reviews the major guidelines available on the management of metastatic RCC and tries to put them into context.
Preface
Authors: Saad Fred
Published: May 2009

It was with pleasure that I accepted to serve as editor of this timely supplement dedicated to kidney cancer. [...]
Reversible intramolecular photocycloaddition of a bis(9-anthrylbutadienyl)paracyclophane – an inverse photochromic system. (Photoactive cyclophanes 5)
Authors: Hopf Henning , Beck Christian , Desvergne Jean-Pierre , Bouas-Laurent Henri , Jones Peter G , Ernst Ludger
Published: May 2009

The title compound, 4,13-bis[(1E,3E)-4-(9-anthracenyl)buta-1,3-dienyl][2.2]paracyclophane (2), prepared in 35% overall yield from [2.2]paracyclophane, absorbs light at λmax = 400 nm with a tail down to 480 nm. By irradiation into this band, 2 generates a single photoproduct, 4, whose absorption maximum is situated at 306 nm. The starting material is recovered by irradiation at 306 nm or by heating. This ‘inverse’ photochromic system has a potential for optical information storage, compound 4 being stable in visible light, at ambient temperature.
Rough‐and‐tumble play and the regulation of aggression: an observational study of father–child play dyads
Authors: Flanders Joseph L. , Leo Vanessa , Paquette Daniel , Pihl Robert O. , Séguin Jean R.
Published: May 2009

Rough‐and‐tumble play (RTP) is a common form of play between fathers and children. It has been suggested that RTP can contribute to the development of selfregulation. This study addressed the hypothesis that the frequency of father–child RTP is related to the frequency of physically aggressive behavior in early childhood. This relationship was expected to be moderated by the dominance relationship between father and son during play. Eighty‐five children between the ages of 2 and 6 years were videotaped during a free‐play session with their fathers in their homes and questionnaire data was collected about father–child RTP frequency during the past year. The play dyads were rated for the degree to which the father dominated play interactions. A significant statistical interaction revealed that RTP frequency was associated with higher levels of physical aggression in children whose fathers were less dominant. These results indicate that RTP is indeed related to physical aggression, though this relationship is moderated by the degree to which the father is a dominant playmate. Aggr. Behav. 35:285–295, 2009. © 2009 Wiley‐Liss, Inc.
Prätubulysin, eine potente und synthetisch leicht zugängliche Vorstufe von Tubulysin aus Angiococcus disciformis
Authors: Ullrich Angelika , Chai Yi , Pistorius Dominik , Elnakady Yasser A. , Herrmann Jennifer E. , Weissmann Kira J. , Kazmaier Uli , Müller Rolf
Published: May 2009

Einfacher geht′s auch: Prätubulysin (Formel ohne die grünen Substituenten), ein vereinfachtes Tubulysin, wurde nicht nur im Labor hergestellt, sondern auch in der natürlichen Tubulysinquelle entdeckt. Diese biosynthetische Vorstufe der Tubulysine ist zwar weniger aktiv als die Tubulysine A und D, wirkt aber immer noch im Pikomolbereich auf eine Reihe von Krebszelllinien.

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Triggered Release of an Active Peptide Conjugate from a DNA Device by an Orally Administrable Small Molecule
Authors: Taylor Steven K. , Pei Renjun , Moon Byoung C. , Damera Srikanth , Shen Aihua , Stojanovic Milan N.
Published: May 2009

Chinin hilft: In einem konzeptionell neuen Ansatz zur gesteuerten Freisetzung wurde das natürliche Insulintagesprofil als Antwort auf drei Mahlzeiten nachgestellt (siehe Graph), indem ein Insulinkonjugat – ausgelöst durch Chinin, einen Bestandteil von Tonic Water – von einer Matrix freigesetzt wurde.

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Using Azobenzene‐Embedded Self‐Assembled Monolayers To Photochemically Control Cell Adhesion Reversibly
Authors: Liu Dingbin , Xie Yunyan , Shao Huawu , Jiang Xingyu
Published: May 2009

Mal freundlich, mal abweisend: Mithilfe einer gemischten selbstorganisierten Monoschicht aus zweierlei Alkanthiolen – eines mit einer Azobenzoleinheit und einer Peptid‐Endgruppe, das andere mit einer Hexa(ethylenglycol)‐Kette, die eine nichtspezifische Zelladhäsion verhindert – gelang es, die Zelladhäsion photochemisch zu steuern. Beim reversiblen Übergang zwischen E‐ und Z‐konfigurierter Azobenzoleinheit wechselt das Zelladhäsionsverhalten der Oberfläche (siehe Bild).

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A p‐Type NiO‐Based Dye‐Sensitized Solar Cell with an Open‐Circuit Voltage of 0.35 V
Authors: Gibson Elizabeth A. , Smeigh Amanda L. , Le Pleux Loïc , Fortage Jérôme , Boschloo Gerrit , Blart Errol , Pellegrin Yann , Odobel Fabrice , Hagfeldt Anders , Hammarström Leif
Published: May 2009

In tandem: Employing a molecular dyad and a cobalt‐based electrolyte gives a threefold‐increase in open‐circuit voltage (VOC) for a p‐type NiO device (VOC=0.35 V), and a fourfold better energy conversion efficiency. Incorporating these improvements in a TiO2/NiO tandem dye‐sensitized solar cell (TDSC), results in a TDSC with a VOC=0.91 V (see figure; CB=conductance band, VB= valence band).

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Triggered Release of an Active Peptide Conjugate from a DNA Device by an Orally Administrable Small Molecule
Authors: Taylor Steven K. , Pei Renjun , Moon Byoung C. , Damera Srikanth , Shen Aihua , Stojanovic Milan N.
Published: May 2009

A real tonic: In a conceptually new approach to controlled release, the natural daily insulin profile in response to three meals is mimicked (see graph) with release of an insulin conjugate from a matrix, triggered by quinine, a component of tonic water.

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Is Enantioselectivity Predictable in Asymmetric Catalysis?
Authors: Brown John M. , Deeth Robert J.
Published: May 2009

Seeing into the future: A range of computational methods have been applied to harmonize predicted ee values with experimental values. Novel ways of combining quantum mechanics and molecular mechanics feature prominently.

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Using Azobenzene‐Embedded Self‐Assembled Monolayers To Photochemically Control Cell Adhesion Reversibly
Authors: Liu Dingbin , Xie Yunyan , Shao Huawu , Jiang Xingyu
Published: May 2009

A celling point: A mixed self‐assembled monolayer comprising two types of alkanethiols—one containing an azobenzene unit terminated with a peptide, the other containing a hexa(ethylene glycol) group that resists nonspecific cell adhesion—enables cell adhesion to be modulated photochemically. The reversible conversion of the azobenzene moiety between E and Z configurations allows the surface to either support or resist cell adhesion.

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Molecular Rods with Oligospiroketal Backbones as Anchors in Biological Membranes
Authors: Müller Peter , Nikolaus Jörg , Schiller Sabine , Herrmann Andreas , Möllnitz Kristian , Czapla Sylvia , Wessig Pablo
Published: May 2009

Getting stuck in: A hydrophobic molecular rod with terminal fluorescent moieties has been synthesized. The insertion of the rod into membranes was investigated and shown to incorporate efficiently into model and biological membranes (see picture; gray C, blue N, red O). Those rods can be used as stable membrane‐associated anchors for functionalization of membrane surfaces.

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Processability and mechanical properties for binary blends of PP and LLDPE produced by metallocene catalyst
Authors: Ono Kazuya , Ogita Hiroaki , Okamoto Kenzo , Yamaguchi Masayuki
Published: May 2009

Processability at extrusion coating and mechanical properties of the films obtained are investigated by means of linear and nonlinear rheological measurements and tensile tests for blends of polypropylene (PP) and linear low‐density polyethylene (LLDPE). Both materials are produced by metallocene catalyst. The processability of PP is found to be improved by the addition of LLDPE; the blend shows low level of motor torque and head pressure in an extruder and small level of neck‐in as compared with pure PP. Further, the anisotropy of ultimate tensile strength, which is prominent for PP, is reduced by blending with LLDPE. As a result, the blend having 20 wt % of LLDPE shows appropriate properties in the molten state for extrusion coating and in the solid state as a film. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Modification of poly(vinyl chloride) by IPN formation with poly(ethyl acrylate)
Authors: Chakrabarti Rupa , Chakraborty Debabrata
Published: May 2009

Semi‐1 and semi‐2 interpenetrating polymer networks (IPNs) of poly(vinyl chloride) (PVC) and in situ formed poly(ethyl acrylate) (PEA) have been synthesized using diallyl phthalate and ethylene glycol dimethacrylate as the crosslinkers of PVC and PEA, respectively. These two types of IPNs have been compared with respect to their physical, mechanical, and thermal properties and an endeavor has been made to find a correlation of these properties with the morphology generated in these systems. The semi‐1 IPNs displayed a decrease in their tensile strength and modulus while in contrast; the semi‐2 IPNs exhibited a marginal increase with increasing crosslinked PEA incorporation. The semi‐1 and semi‐2 IPNs containing 10 and 30 wt % of PEA displayed a two‐stage degradation typical of PVC in their thermogravimetric and DSC studies while confirming the increased stability of the samples with higher percentages of PEA. The softening characteristics as detected by the extent of penetration of the thermomechanical probe as has been detected by thermomechanical analysis are in conformity with their mechanicals. The biphasic cocontinuous systems as explicit from the morphological studies reveal fibrillar characteristics in both the systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Kinetics and mechanism of the radical copolymerization of 4‐vinyl pyridine with methyl acrylate initiated by p‐acetylbenzylidene triphenylarsonium ylide
Authors: Tiwari S. P. , Gehlot C. L.
Published: May 2009

The free‐radical copolymerization of 4‐vinyl pyridine (4‐VP) with methyl acrylate (MA) initiated by p‐acetylbenzylidene triphenylarsonium ylide at 60 ± 0.1°C with dioxane as an inert solvent yielded random copolymers. The kinetic equation was Rp ∝ [Ylide]0.83[4‐VP]0.33 [MA]0.40 (where Rp is the rate of polymerization); in other words, the system followed nonideal kinetics. The values of the energy of activation and kp2/kt (where kp is the rate constant of propagation and kt is the rate constant of termination) were 23.21 kJ/mol and 1.212 × 10−5 mol L−1 s−1, respectively. The reactivity ratios calculated with the Kelen–Tüdos method were 0.14 ± 0.0075 for 4‐VP and 0.56 ± 0.0078 for MA. The copolymers were characterized with Fourier transform infrared, proton nuclear magnetic resonance, differential scanning calorimetry, and electron spin resonance methods. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The effects of steaming of beech (Fagus orientalis L.) and sapele (Entandrophragma cylindricum) woods on the adhesion strength of varnish
Authors: Kılıç Murat
Published: May 2009

In this study, it was investigated how steaming of beech (Fagus orientalis L.) and sapele (Entandrophragma cylindricum) woods effect the adhesion strength of some varnish types. With this objective, first of all, the surface roughnesses of the steamed and unsteamed specimens having tangential and radial surfaces and prepared from beech and sapele were measured (Kiliç et al., J Mat Proc Tech 2008, 199, 448). Subsequently, cellulosic, polyurethane and water‐based bright varnishes were applied on these surfaces according to the principles stated in ASTM D 4541 and TS EN 24624 and the adhesion strength of the varnished layers were determined. According to the results of the study, the effects of the type of wood, steaming, surface and varnish types were found to be significant in the adhesion strength to the surfaces of the different varnish layers applied to the surfaces of different wooden materials. It was found that beech wood had a higher adhesion strength than sapele wood. The adhesion strength of steamed wooden materials had a lower strength compared with those that were unsteamed. The adhesion strength of specimens with a radial surface were found to be higher than the specimens with tangential surfaces. Whereas, in the varnish types, the highest adhesion strength was obtained with the polyurethane varnish, which completed the chemical reaction on the surfaces of the wooden material. In conclusion, it could be proposed to use beech wood materials having a radial surface in the jobs requiring a high adhesion strength, to sand once again the material due to the increase in roughness of steaming and to use polyurethane varnish. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Nano/micro ternary composites based on PP, nanoclay, and CaCO3
Authors: Sorrentino L. , Berardini F. , Capozzoli M.R. , Amitrano S. , Iannace S.
Published: May 2009

Nano‐/microcomposites based on polypropylene/montmorillonite/calcium carbonate were prepared by melt mixing. Their structures and properties were characterized by small‐angle X‐ray diffraction, thermal analysis, and rheological measurements. The intercalation degree was found to be dependent on the compatibilizer content and the processing temperature. The addition of the organoclay slightly increased the melt crystallization temperature of polypropylene, acting as nucleating agents, and improved the degree of crystallinity. The rheological tests showed that nanocomposites increased the complex viscosity when compared with the microcomposites with the same filler content and exhibited a pronounced shear‐thinning behavior in the low frequency range. A Carreau‐Yasuda model was used to model the rheological behavior of these materials. The nano‐/microcomposites showed a significant improvement (about 50%) of the Young's modulus when compared with microcomposites with the same filler content due to the intercalation or exfoliation of the organoclay and the enhanced degree of crystallinity. Moreover, some formulations showed an enhancement of elongation at break and ultimate strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Membranes of cellulose triacetate produced from sugarcane bagasse cellulose as alternative matrices for doxycycline incorporation
Authors: Rodrigues Filho Guimes , Toledo Leandra Cardoso , Da Silva Leandro Gustavo , De Assunção Rosana Maria Nascimento , Meireles Carla da Silva , Cerqueira Daniel Alves , Ruggiero Reinaldo
Published: May 2009

Cellulose triacetate (CTA) membranes were prepared using polyethylene glycol, 600 g mol−1, (PEG) as additive and were utilized in essays of doxycycline (DOX) incorporation using two different procedures: (i) incorporation of the drug during the membrane preparation and (ii) incorporation of the drug to a previously prepared membrane. In the first, the produced membrane presented high compatibility between DOX and CTA, what was evidenced by analyzing the DSC curve for a CTA/PEG 50%/DOX system. Results showed that the drug is homogeneously distributed throughout the matrix, molecularly. In the second method, the drug was molecularly and superficially adsorbed, as seen through the DSC curve for the system CTA/PEG 10%/DOX, which nearly does not present alterations in relation to the original material, and through the isotherm of drug adsorption that follows the Langmuir model. Results showed that the membranes produced from sugarcane bagasse are adequate to produce matrices for drug‐controlled release, both for enteric use (Method (i)) and topic use (Method (ii)). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Polyethylene/aluminum nanocomposites: Improvement of dielectric strength by nanoparticle surface modification
Authors: Huang Xingyi , Ma Zhisen , Wang Yaqun , Jiang Pingkai , Yin Yi , Li Zhe
Published: May 2009

The effect of the surface modification with a silane coupling agent (octyl‐trimethoxysilane) of aluminum (Al) nanoparticles on the dielectric breakdown behaviors of polyethylene (PE)/Al nanocomposites was investigated in comparison of the influence of the improvement of the interfacial adhesion between Al nanoparticles and PE using a compatibilizer (maleic anhydride grafted polyethylene). It was found that when compared with the other modification approaches, the surface‐treated Al nanofiller with the silane coupling agent makes it possible for the PE/Al nanocomposites to still keep the relatively higher breakdown strength even in the higher Al loading level above 14 vol %, which can be understood in terms of the better interfacial adhesion between the surface‐treated particle dispersion and the matrix. The combined effects of the Al nanoparticles on the different factors which influence the dielectric breakdown processes in polymer matrix such as microstructure, conductivity, and crystallinity of the nanocomposites were discussed in detail. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermo‐responsive injectable hydrogel system based on poly(N‐isopropylacrylamide‐co‐vinylphosphonic acid). I. Biomineralization and protein delivery
Authors: Kim So Yeon , Lee Sang Cheon
Published: May 2009

To achieve the injectable hydrogel system in order to improve bone regeneration by locally delivering a protein drug including bone morphogenetic proteins, thermo‐responsive injectable hydrogels composed of N‐isopropylacrylamide (NIPAAm) and vinyl phosphonic acid (VPAc) were prepared. The P(NIPAAm‐co‐VPAc) hydrogels were also biomineralized by urea‐mediation method to create functional polymer hydrogels that deliver the protein drug and mimic the bone extracellular matrix. The loosely cross‐linked P(NIPAAm‐co‐VPAc) hydrogels were pliable and fluid‐like at room temperature and could be injected through a small‐diameter aperture. The lower critical solution temperature (LCST) of P(NIPAAm‐co‐VPAc) hydrogel was influenced by the monomer ratio of NIPAAm/VPAc and the hydrogel with a 96/4 molar ratio of NIPAAm/VPAc exhibited an LCST of ∼34.5°C. Water content was influenced by temperature, NIPAAm/VPAc monomer ratio, and biomineralization; however, all hydrogels maintained more than about 77% of the water content even at 37°C. In a cytotoxicity study, the P(NIPAAm‐co‐VPAc) and biomineralized P(NIPAAm‐co‐VPAc) hydrogels did not significantly affect cell viability. The loading content of bovine serum albumin in hydrogel, which was used as a model drug, gradually increased with the amount of VPAc in the hydrogel owing to the ionic interaction between VPAc groups and BSA molecules. In addition, the release behavior of BSA from the P(NIPAAm‐co‐VPAc) hydrogels was mainly influenced by the drug loading content, water content, and biomineralization of the hydrogels. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Micromorphology of macromolecular superabsorbent polymer and its fractal characteristics
Authors: Yunkai Li , Tingwu Xu , Zhiyun Ouyang , Xiongcai Lin , Honglu Liu , Zhongyong Hao , Peiling Yang
Published: May 2009

Superabsorbent polymer (SAP) can absorb a solution of 10‐folds to 1000‐folds as much as its own weight. Its micromorphology directly affects its water absorption mechanism and absorption characteristics. In this work, we selected three types of polymer products for research analysis: KH (sodium polyacrylate‐type), HLM (polyacrylamide‐type), and AS (polyacrylamide‐kaliumcrylic acid‐crosslinking‐copolymer‐type). The environmental scanning electronic microscope (ESEM) method and the fractal theory are applied for studying the micromorphology of the three types of SAPs. The results show that KH possesses the highest water absorption multiplying factor and HLM possesses the lowest one. Under the condition of repeated water absorption and water release, the structure of HLM hydrogel transfers from gridding membrane to network structure. Various types of cation solutions significantly affect the characteristics of micromorphology of HLM hydrogel, and both uniqueness and diversity prevail. Under the condition of repeated water absorption and water release, the swelling multiplying factor of HLM in deionized water abides by an “inverted U” distribution. The water absorption multiplying factor for the third time is the largest one. This is primarily caused by both reduction of resilience of crosslinking network and dissolution of polymer on the surface of hydrogel under the condition of repeated water absorption and water release. The boundary of hydrogel pore network of the three types of SAPs possesses fractal characteristics. The number of fractal dimensions is as follows: fractal dimension of HLM < fractal dimension of AS < fractal dimension of KH. With the increase of the number of repeated water absorption and water release, the number of fractal dimensions of cross‐sectional pore boundary reduces, that is, T1 (1.3848) > T3 (1.2100) > T5 (1.1226). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Adsorption of Hg2+ on a novel chelating fiber prepared by preirradiation grafting and amination
Authors: Yang Ying , Ma Nianfang , Zhang Qikun , Chen Shuixia
Published: May 2009

A novel chelating fiber was prepared by the irradiation‐induced grafting copolymerization of glycidyl methacrylate on polypropylene fiber and consequent amination with diethylenetriamine. The effects of the reaction conditions, such as reaction time, temperature, and monomer concentration, on the degree of grafting were investigated. The optimal conditions for grafting were found to be 3 h, 100°C, and a 50% (v/v) glycidyl methacrylate concentration in tetrahydrofuran solution. This fiber showed good adsorption performance at different concentrations of Hg2+, in particular for trace Hg2+. Under the adsorption conditions of pH = 4, initial concentration = 1000 mg/L, and time = 20 h, the adsorption capacity of the chelating fiber for Hg2+ reached 785.28 mg/g. It completely adsorbed the Hg2+ ions in solution within a short contact time, showing a very high adsorption rate for Hg2+. Furthermore, the chelating fiber also had a high selectivity for mercury, whereas Cu2+ coexisted in different concentrations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Alkali treatments of lyocell in continuous processes. I. Effects of temperature and alkali concentration on the treatments of plain woven fabrics
Authors: Siroky Jan , Manian Avinash P. , Siroka Barbora , Abu‐Rous Mohammad , Schlangen Joerg , Blackburn Richard S. , Bechtold Thomas
Published: May 2009

Experiments were conducted that were designed to study the influence of various process parameters on the properties of lyocell fabrics treated with NaOH solutions in a continuous process. The process parameters of interest were the fabric type (plain, twill, or sateen woven), alkali concentration, tension on the fabric, temperature, and duration of the treatment. In this article, we present the first set of results from these experiments and examine the effect of NaOH concentration, temperature, and tension in the continuous alkali treatments of plain woven lyocell fabrics. Alkali treatments caused fiber swelling in the fabrics to extents governed by the alkali concentration and temperature of the treatment liquors. Fiber swelling caused fabric shrinkage, which resulted in changes to the fabric macroscopic structure and properties. Changes were observed in the flexural rigidity, water retention, crease recovery, strength, and abrasion resistance of the fabrics to extents governed predominantly by swelling‐related changes to the fabric structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009