bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polysilanes. A New Route Toward High Performance EL Devices
Authors: Sacarescu Liviu , Mangalagiu Ionel , Simionescu Mihaela , Sacarescu Gabriela , Ardeleanu Rodinel 
Published: July 2008

AbstractThe discovery of a remarkable class of plastics that can conduct electricity has opened a new era of plastics science and technology that has just been recognized by the award of the 2000 Nobel prize for chemistry. They can be used to make a wide range of electronic devices such as transistors, light‐emitting diodes, solar cells and even lasers, through much simpler manufacture than conventional inorganic materials, increasing flexibility, reducing cost, and opening up new markets. Polysilanes are subject of an intensive research work aiming to various optoelectronic applications. Through this work the chemical structure of polydiphenylsilane was modified to obtain both solubility in common solvents and to induce new properties by attaching of various organic segments.
Comparative study of some metallic biomaterials used as implants
Authors: Al‐Mobarak N. A. 
Published: July 2008

AbstractThe electrochemical behavior of two Ti alloys (TA and TAV) and two grades of stainless steels (SS1 and SS2), commonly used as biomedical implant materials, particularly for orthopedic and osteosynthesis applications, was investigated in Hank's solution at 37 °C and different pH. The aim was to distinguish between the behavior of these materials in artificial physiological solution through analysis of their corrosion potential variation with time and potentiodynamic polarization curves. Characterization of the modified surface layers was made by means of microscopic examinations, hardness measurements and X‐ray diffraction analysis. The results indicated that in neutral Hank's solution (pH = 7.2) SS2 and SS1 samples were of higher corrosion resistance than titanium alloys. The behavior was reversed in the acidic media (pH = 5.0 or 3.0), where TA had the least corrosion rate and the corrosion susceptibility increased in the order TA < TAV < SS1 < SS2.
Granulare ultradünne Nanoschichtsysteme Fe/FeO auf Aluminiumsubstrat, Modellierung einer 1 D ultradünnen granularen Schicht für elektromagnetische Verträglichkeitsanwendungen (EMV) der Flachbandkabeltechnik
Authors: Gräbner F. , Hirsch D. , Herrmann R. , Rabe C. , Winkler R. , Müller T. , Hungsberg A. , Kallmeyer Ch. 
Published: July 2008

AbstractDie magnetischen Verluste, welche nach dem phänomenologischen Modell von Landau Lifschitz betrachtet werden, können unter Nutzung der mikroskopischen und makroskopischen Werkstoffeigenschaften entwickelt werden. Jedoch beziehen sich diese Betrachtungen auf kristalline Schichten und nicht auf reale granulare Strukturen. Granulare Strukturen sollen [ 2 ] eine höhere Absorption der elektromagnetischen Energie realisieren können als kristalline Schichten.Ziel dieser Arbeit ist es ein Simulationsmodell unter Nutzung realer amorpher und kristalliner Schichteigenschaften aufzubauen und einen Designhinweis zur Entwicklung einer Schicht hin zu höheren Absorptionen aufzuzeigen. Die erhöhte Absorption der granularen Nanomaterialien soll in elektromagnetischer Verträglichkeitsanwendungen (EMV) für Leitungen und Schichten für Entstörfolien eingesetzt werden. Eine RF – Materialanalyse, eine AFM ‐ Schichtanalyse und EMV ‐ Analyse schließt den Kreis zum Materialdesign und EMV zur Industrieanwendung als Absorbermaterial bzw. Entstörmaterial.
Nichtmagnetisierbarer warmbeständiger nichtrostender Stahl für Wälzlager
Authors: Riedner S. , Berns H. , Tyshchenko A. I. , Gavriljuk V. G. , Schulte‐Noelle C. , Trojahn W. 
Published: July 2008

AbstractDurch Legieren von Chrom‐Mangan‐Stählen mit rund 1 % Kohlenstoff und Stickstoff wurde ein kostengünstiger, unter Normaldruck erschmelzbarer austenitischer Stahl entwickelt, der über eine neue und erstaunliche Eigenschaftskombination verfügt. Ausgehend von einer Streckgrenze um 600 MPa lässt er sich durch Kaltverformen auf eine Härte von 60 HRC verfestigen. Diese hohe Härte wird erstmals ohne das für Wälzlager übliche Martensitgefüge erzielt. Er ist außerdem nichtrostend, nichtmagnetisierbar und bis rund 500 °C warmbeständig, d. h. ein Werkstoff für komplexe Betriebsbedingungen.Die Herstellbarkeit durch Blockguss, ESU, Warmumformen, Lösungsglühen und Drehbearbeiten wurde im industriellen Maßstab nachgewiesen. Die Untersuchung der Struktur des neuen Stahles erfolgte mehrskalig, beginnend bei der Elektronenstruktur und weiter über die Feinstruktur im Elektronenmikroskop, die Mikrostruktur im Lichtmikroskop bis hin zur Makroätzung. So konnte ein weitgehendes Verständnis für die außergewöhnliche Eigenschaftskombination des neuen, mit CARNIT bezeichneten Stahles gewonnen werden.
Mechanical property analysis of Nitinol defective stent under uniaxial loading/unloading
Authors: Zhi Y.H. , Wang X.M. , Gao Z.Z. , Liu Y.S. , Yue Z.F. 
Published: July 2008

AbstractThe vascular stents are important medical devices introduced into a vessel to protect the lumen from unfriendly stenosis. However, Nitinol stent is easy to fail in practice. The present paper focuses on the influence of defects on its mechanical behavior by finite element analysis. The essential stent cell is used with two different type of defects, which includes the face bulge defect resulted from laser burrs or TiC inclusion arises and C‐contained particle voids. Auricchio’s super‐elastic consititutive equations are used in the finite element simulations. It is found that the stress distribution is not only related to the defect type but also to the defect position. With the increasing distance from the TiC defect to the knot’s notch, the influence of defects on stress distribution of stents becomes small. For void defects, those near both the inner fillet and the outer fillet have grand influence on the stent’s global stress distribution. In particular, the higher stress concentrations are undergone near knot’s defects. For all models, the maximum Martensite Volume Fraction is near knots. The finite element analysis shows that cracks/fractures can easily appear near knots. A stent with a TiC inclusion or void defect is likely to fail. All obtained conclusions can be useful to design against stent premature mechanical failure.
Rad51 overexpression rescues radiation resistance in BRCA2‐defective cancer cells
Authors: Brown Erika T. , Holt Jeffrey T. 
Published: July 2008

AbstractBreast cancers with BRCA2 mutations exhibit DNA repair defects and are particularly sensitive to radiation. BRCA2 interacts with Rad51 in a complex manner involving internal BRC and C‐terminal TR2 domains which play a key role in homologous recombination. BRCA2 expression also modulates Rad51 protein levels such that Rad51 protein is relatively decreased in BRCA2‐defective cancer cells. This is mediated in part through BRCA2's capacity to protect Rad51 from caspase‐3 proteolytic degradation. In order to distinguish between functional and expression related roles for BRCA2 we studied the results of Rad51 overexpression in mouse and human cells with inactivating BRCA2 mutations. The results show that overexpression of wild‐type Rad51 partially rescues BRCA2 deficiency but that overexpression of a caspase‐3 resistant Rad51 completely complements the BRCA2 defect in radiation responsiveness. These results indicate that Rad51 can compensate for some aspects of a BRCA2 gene defect and suggest that Rad51 expression levels may be an important modifier of the BRCA2 defective genotype. © 2008 Wiley‐Liss, Inc.
Molecular mechanisms of Nrf2‐mediated antioxidant response
Authors: Li Wenge , Kong Ah‐Ng 
Published: July 2008

AbstractNrf2 is the key transcription factor regulating the antioxidant response. Nrf2 signaling is repressed by Keap1 at basal condition and induced by oxidative stress. Keap1 is recently identified as a Cullin 3‐dependent substrate adaptor protein. A two‐sites binding “hinge & latch” model vividly depicts how Keap1 can efficiently present Nrf2 as substrate for ubiquitination. Oxidative perturbation can impede Keap1‐mediated Nrf2 ubiquitination but fail to disrupt Nrf2/Keap1 binding. Nrf2 per se is a redox‐sensitive transcription factor. A new Nrf2‐mediated redox signaling model is proposed based on these new discoveries. Free floating Nrf2 protein functions as a redox‐sensitive probe. Keap1 instead functions as a gate keeper to control the availability of Nrf2 probes and thus regulates the overall sensitivity of the redox signaling. © 2008 Wiley‐Liss, Inc.
Effectiveness of acupuncture for Parkinson's disease: A systematic review
Authors: Lee Myeong Soo , Shin Byung‐Cheul , Kong Jae Cheol , Ernst Edzard 
Published: July 2008

AbstractThe objective of this review is to assess the clinical evidence for or against acupuncture as a treatment for Parkinson's disease (PD). We searched the literature using 17 databases from their inception to September 2007 (searched again 3rd January 2008), without language restrictions. We included all randomized clinical trials (RCTs) regardless of their design. Methodological quality was assessed using the Jadad score. Eleven RCTs met all inclusion criteria. Three RCTs assessed the effectiveness of acupuncture on Unified Parkinson's Disease Rating Scale (UPDRS) compared with placebo acupuncture. A meta‐analysis of these studies showed no significant effect (n = 96, WMD, 5.7; 95% CI −2.8 to 14.2, P = 0.19, heterogeneity: tau2 = 0, χ2 = 0.97, P = 0.62, I2 = 0%). Another six RCTs compared acupuncture plus conventional drugs on improvement of symptoms of PD with drugs only. A meta‐analysis of two of these studies suggested a positive effect of scalp acupuncture (n = 106, RR, 1.46, 95% CI = 1.15 to 1.87, P = 0.002; heterogeneity: tau2 = 0.00, χ2 = 1.14, P = 0.29, I2 = 12%). Two further RCTs tested acupuncture versus no treatment. The meta‐analysis of these studies also suggested beneficial effects of acupuncture. The results of the latter two types of RCTs fail to adequately control for nonspecific effects. In conclusion, the evidence for the effectiveness of acupuncture for treating PD is not convincing. The number and quality of trials as well as their total sample size are too low to draw any firm conclusion. Further rigorous trials are warranted. © 2008 Movement Disorder Society
Uric acid in Parkinson's disease
Authors: Schlesinger Ilana , Schlesinger Naomi 
Published: July 2008

AbstractRecent studies have provided evidence that uric acid may play a role in the development and progression of Parkinson's disease (PD). Uric acid is a natural antioxidant that may reduce oxidative stress, a mechanism thought to play a role in the pathogenesis of PD. Higher levels of serum urate (SU) may have a neuroprotective effect. High SU levels reduced the risk of developing PD and correlated with slower PD progression. Among PD patients SU levels were lower as compared with controls. The manipulation of SU levels holds promise in the treatment of PD. It is possible that a high purine diet in patients with PD may slow progression of the disease. Milk and meat consumption as well as exercise modify the risk of developing PD possibly through their influence on SU levels. In this article, we review the association between PD and SU levels and its implication on the management of PD. © 2008 Movement Disorder Society
Emergence of Parkinson's disease in essential tremor: A study of the clinical correlates in 53 patients
Authors: Minen Mia T. , Louis Elan D. 
Published: July 2008

AbstractPatients with essential tremor (ET) may develop Parkinson's disease (PD); however, few studies have examined the clinical features of this combination syndrome. Fifty‐three patients with ET‐PD were studied and compared to 53 PD and 150 ET patients. Although the latency from onset of ET to PD was brief (<5 years) in 38.5%, in a sizable proportion (30.8%), it was very long (>20 years). The gender distribution of ET‐PD (67.9% male) was identical to that of PD (67.9% male), yet differed from that of ET (50.0% male) (P = 0.02). The initial cardinal sign of PD was rest tremor in 100% of patients. In ET‐PD, the side of greatest initial ET severity usually matched that of greatest PD severity (P < 0.05). In ET‐PD, male gender predominated and the sidedness of the ET and PD usually matched. The co‐occurrence of the two diagnoses in the same patient may be mechanistically related. © 2008 Movement Disorder Society
Benign nocturnal alternating hemiplegia of childhood: The first clinical report with paroxysmal events home‐video recordings
Authors: Sartori Stefano , Vecchi Marilena , Toldo Irene , Boniver Clementina , Dalla Bernardina Bernardo , Maria Laverda Anna 
Published: July 2008

AbstractBenign familial nocturnal alternating hemiplegia of childhood (BNAHC) is a rare disorder characterized by recurrent attacks of hemiplegia, arising from sleep without progression to neurological or intellectual impairment. It is distinct from the malignant, relatively more common, alternating hemiplegia of childhood (AHC), complicated by developmental deterioration, cognitive impairment, and permanent neurological deficits such as choreoathetosis. The authors add a new case of BNAHC to the pertinent literature and report, for the first time, a video with the typical nocturnal hemiplegic attacks in order to improve knowledge about this disorder among child neurologists and pediatricians and increase the possibility of clarifying its pathogenesis and molecular basis. © 2008 Movement Disorder Society
Free DIEP and SIEA breast reconstruction to internal mammary intercostal perforating vessels with arterial microanastomosis using a mechanical coupling device
Authors: Rad Ariel N. , Flores Jaime I. , Rosson Gedge D. 
Published: July 2008

AbstractAutologous breast reconstruction with microsurgical free tissue transfer has become routine, and perforator‐based adipocutaneous flaps are recognized as an excellent option for many patients. Current efforts to optimize patient outcomes focus on minimizing operative morbidity both at the donor and recipient sites. The DIEAP flap avoids most of the abdominal wall morbidity associated with the TRAM. At the recipient site, however, partial rib resection, for access to the internal mammary (IM) artery and vein as recipient vessels, has a risk of chest wall pain, deformity, and pneumothorax. Perhaps more importantly, sacrifice of the IM vessels precludes their use for potential future coronary revascularization. To avoid this, the intercostal perforating branches from the internal mammary system may be used as recipient vessels for microanastomosis. This has been well described using suture technique, although the use of a mechanical coupling device for arterial anastomosis to the perforator has not been reported. We report nine cases whereby a mechanical coupling device was used to perform both the arterial and venous anastomoses of DIEAP and SIEA flap pedicles to IM intercostal perforating vessels. Flap ischemia time was shorter in all cases, allowed ease of anastomosis for vessel size mismatch, and is technically easier in deep wounds. This technique is a further refinement to free flap breast reconstruction and is a powerful application of the coupling device. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Combination of fillet and triangular flaps for the web reconstruction in pollicization: A case report
Authors: Karacaoglu Ercan , Baran Cihat N. , Baran Namik Kemal 
Published: July 2008

AbstractThumb hypoplasia represents a major disability requiring sophisticated reconstructive procedures. One of the basic criteria of the pollicization to construct a functional thumb is scar free web reconstruction. In this article, a technique to avoid excessive scarring in the first web space reconstruction by filleting out the hypoplasic thumb combining with a triangular flap is presented. A 5‐year‐old girl was presented. She had a Back‐Gramcko type IV thumb hypoplasia. A triangular flap was planned on radial border of the long finger. Floating thumb was filleted out with preservation of the neurovascular bundle and transferred to the first web space while cooperating with triangular flap. Patient was followed up for 18 months. No early or late major complication was seen. Flap healed without any necrosis. The ratio of active motion in pollicized finger was measured 60% after cerebral reorientation. A satisfactory grip and pinch were seen in pollicized finger. Patient as well as her parents was satisfied with the results. Filleting out the floating thumb and combining with a triangular flap harvested by a V‐Y flap design is a good option to avoid excessive scarring in reconstruction of the first web space in pollicization. It is strongly recommended that floating thumb should be preserved for future pollicization, and any attempt to amputate it in early years of life should be postponed till the time of definitive surgery. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Existence of global solutions to a model of chondrogenesis
Authors: Kazmierczak B. 
Published: July 2008

AbstractThe paper considers conditions sufficient for the existence of classical C solutions to a new model of chondrogenesis during the vertebrate limb formation. We assume that the diffusion coefficient of the fibronectin is positive and that the function describing the interaction between the fibronectin and cells satisfies some additional properties. Copyright © 2008 John Wiley & Sons, Ltd.
A critical evaluation of drug interactions with Echinacea spp.
Authors: Freeman Camille , Spelman Kevin 
Published: July 2008

AbstractAccurate information concerning drug–herb interactions is vital for both healthcare providers and patients. Unfortunately, many of the reviews on drug–herb interactions contain overstated or inaccurate information. To provide accurate information on drug–herb interactions healthcare providers must account for product verification, dosage, medicinal plant species, and plant part used. This critical review assessed the occurrence of drug interactions with one of the top selling botanical remedies, echinacea including Echinacea angustifolia, E. pallida, and E. purpurea. Only eight papers containing primary data relating to drug interactions were identified. Herbal remedies made from E. purpurea appear to have a low potential to generate cytochrome P450 (CYP 450) drug–herb interactions including CYP 450 1A2 (CYP1A2) and CYP 450 3A4 (CYP3A4). Currently there are no verifiable reports of drug–herb interactions with any echinacea product. However, further pharmacokinetic testing is necessary before conclusive statements can be made about echinacea drug–herb interactions. Given our findings, the estimated risk of taking echinacea products (1 in 100 000), the number of echinacea doses consumed yearly (> 10 million), the number of adverse events (< 100) and that the majority of use is short term, E. purpurea products (roots and/or aerial parts) do not appear to be a risk to consumers.
Effects of the mycotoxin deoxynivalenol on human primary hepatocytes
Authors: Königs Maika , Schwerdt Gerald , Gekle Michael , Humpf Hans‐Ulrich 
Published: July 2008

AbstractToxic effects of the mycotoxin deoxynivalenol (DON) observed in animals range from diarrhea, vomiting, gastro‐intestinal inflammation to necrosis of several tissues. In the last years, DON has been tested in hepatocytes of several animal species for its cytotoxicity. However, these tests are limited to the use of animal cells. No studies using human hepatocytes are available. Further investigations with the human hepatocellular liver carcinoma cell line HepG2 might be limited due to the disadvantages of cell lines (e. g.immortalization, tumor derivation, longtime cultivation) and do not necessarily reflect the response of normal human cells. In order to overcome this problem and to be closer to the human situation, we studied the effect of DON in human primary hepatocytes and compared these data to the effects in the HepG2 cell line. Cell viability, apoptotic and necrotic cell death, albumin secretion and metabolic activity were determined. It could be demonstrated that DON has a distinct cytotoxic effect on human primary hepatocytes. Viability, protein content and albumin secretion were reduced in a dose‐dependent manner. The apoptotic key enzyme caspase‐3 was activated, while LDH release occurred only after long incubation time due to a secondary necrosis. Furthermore, we studied the metabolism of DON using LC‐MS/MS. DON was neither metabolized by primary hepatocytes cells nor by the HepG2 cell line.
The influence of metabolism on the genotoxicity of catechol estrogens in three cultured cell lines
Authors: Gerstner Silke , Glasemann Dörte , Pfeiffer Erika , Metzler Manfred 
Published: July 2008

AbstractThe 2‐ and 4‐hydroxy metabolites of 17β‐estradiol (E2) and estrone (E1) are important for E2‐mediated carcinogenesis due to the formation of genotoxic ortho‐quinone metabolites. To assess the importance of metabolic conjugation for their genotoxicity, the DNA strand‐breaking activity of the four catechol estrogens was determined in three cell lines with different activities of catechol‐O‐methyltransferase (COMT) and UDP‐glucuronosyltransferase (UGT). Most DNA strand breaks were observed in V79 cells, which lack these metabolic activities. 2‐ and 4‐hydroxy‐E2 were 2.5 times more genotoxic than 2‐ and 4‐hydroxy‐E1. MCF‐7 cells exhibit COMT activity, and the incidence of DNA strand breaks decreased with increasing methylation; only the 4‐hydroxy metabolites of E1 and E2, which were poor substrates of COMT, exhibited low genotoxicity. HepG2 cells converted the catechol and methoxy metabolites of E2 to the respective E1 metabolites by 17β‐hydroxysteroid dehydrogenase (HSD). Moreover, methylation and glucuronidation took place. Only 4‐hydroxy‐E1 elicited a weak genotoxic response in these cells. The extensive metabolism in HepG2 cells is proposed to account for the failure of catechol estrogens to induce DNA strand breaks. Thus, metabolism by COMT and UGT and, to a minor extent, by HSD is a major determinant for the genotoxicity of catechol estrogens in target cells.
Model experiments mimicking the human intestinal transit and metabolism of D‐galacturonic acid and amidated pectin
Authors: Knaup Bastian , Kempf Michael , Fuchs Jan , Valotis Anagnostis , Kahle Kathrin , Oehme Anett , Richling Elke , Schreier Peter 
Published: July 2008

AbstractIn order to study the human intestinal transit and metabolism of D‐galacturonic acid and amidated pectin a number of model experiments were carried out. Both substrates were incubated under aerobic conditions at 37°C using saliva (2 min) and simulated gastric juice (4 h). Under anaerobic conditions the substrates were incubated at 37°C using human ileostomy and colostomy fluids, each obtained from three different donors, for 10 and for 24 h, respectively. D‐Galacturonic acid, SCFA (acetic acid, propionic acid, and butyric acid), as well as methanol were analyzed photometrically after carbazole reaction, GC‐flame ionization detection (GC‐FID), and headspace solid‐phase microextraction GC/MS (HS‐SPME‐GC/MS), respectively. D‐Galacturonic acid and amidated pectin were found to be stable during incubations with saliva and simulated gastric juice, whereas both substrates underwent degradation in the course of human ileostomy and colostomy fluid incubations. D‐Galacturonic acid was practically completely decomposed within 10 h and SCFA, with acetic acid as the major representative, were formed up to 98% of the incubated substrate in colostomy effluent. The amidated pectin was only degraded in part, revealing stable amounts of 22–35% and 3–17% in ileostomy (after 10 h) and colostomy fluid (after 24 h), respectively. SCFA were generated up to 59% of the applied amidated pectin. In parallel, 19–60% and 52–67% of the available methyl ester groups were cleaved in the course of incubations with ileostomy and colostomy fluids, respectively. The results demonstrate for the first time that D‐galacturonic acid and amidated pectin are stable in human saliva and simulated gastric juice. The degradation of both compounds during incubation with ileostomy effluent is highlighted, providing evidence for a considerable metabolic potential of the small intestine.