bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural style and evolution of a Late Triassic rift basin in the Central High Atlas, Morocco: controls on sediment deposition
Authors: Baudon Catherine , Fabuel‐Perez Ivan , Redfern Jonathan
Published: November 2009

Late Triassic continental sediments deposited in an active‐rift setting are exposed in the Oukaimeden‐Ourika Valley, located in the Central High Atlas Basin of Morocco. The Oukaimeden Sandstone Formation is dominated by ephemeral and perennial braided fluvial facies, and is an outcrop analogue for Triassic sandstone hydrocarbon reservoirs found in Atlantic margin and North African basins. This paper documents detailed analysis of the outcrop data to investigate the influence of tectonics on deposition and the interplay with climatic controls. The geodynamic evolution of the basin is interpreted to be influenced by Atlantic rifting to the west and the formation of the Tethys Sea to the north, which led to the development of ENE and NNE striking normal faults. The present‐day fault and outcrop geometry reflects later inversion due to the Alpine compression that led to uplift of the High Atlas and subsequent erosion.

The ENE trending rift‐basin is bound by normal faults, which are probably in part reactivated older Hercynian structures. The facies distribution was controlled by a complex interplay of tectonic and climatic controls. Evidence for syn‐sedimentary movement of both fault sets is observed, with stratigraphic thickening and associated progressive change in bedding dip. These faults controlled the basin dimension, geometry of the half‐graben and created the accommodation for sediment deposition. The presence of breccia deposits close to the main ENE bounding faults indicates footwall erosion and deposition of basin margin fans. The location and orientation of the main fluvial system was controlled by these structures, and the main channel belts ran parallel and proximal to the controlling faults, whereas away from the main syn‐depositional faults overbank deposits dominate. Smaller contemporaneous NNE oriented faults are generally shorter with less throw, and had only a limited influence on gross sedimentation patterns. These faults are interpreted to be syn‐sedimentary, displaying characteristics that suggest basal detachment within the Triassic, and as such provide evidence for the extension direction during late Triassic time. A periodic change from ephemeral to perennial systems, with associated changes in architectural style, is potentially attributed to climatic control, although a structural influence cannot be dismissed. Copyright © 2009 John Wiley & Sons, Ltd.
Toxicant-Associated Steatohepatitis in Vinyl Chloride Workers
Authors: Cave Matt , Falkner Keith Cameron , Ray Mukunda , Joshi-Barve Swati , Brock Guy , Khan Rehan , Homme Marjorie Bon , McClain Craig J.
Published: November 2009

Although nonalcoholic steatohepatitis (NASH) is typically associated with obesity, it has also been reported to occur in lean individuals exposed to industrial chemicals. Occupational exposure to vinyl chloride (VC) is a well-documented risk factor for hemangiosarcoma, but has not previously been associated with steatohepatitis. Here we evaluate liver biopsies from 25 nonobese, highly exposed VC workers for steatohepatitis. Next, we evaluate associated metabolic and cytokine abnormalities in affected workers controlled by 26 chemical workers with no to minimal VC exposures, and 11 unexposed, healthy volunteers. Among highly exposed VC workers the prevalence of steatohepatitis was 80%. Of these, 55% had fibrosis and four had hemangiosarcoma. We have coined the term toxicant-associated steatohepatitis (TASH) to describe this condition, which was not explained by obesity or alcohol. Although mean serum transaminases were normal in TASH, total cytokeratin 18, but not the caspase-cleaved fragment, was elevated. Despite the absence of obesity, workers with TASH had insulin resistance with reduced adiponectin levels. TASH was also associated with markedly elevated serum tumor necrosis factor alpha and interleukins 1β, 6, and 8. Serum antioxidant activity was reduced in TASH.

Conclusion:

TASH occurred frequently in these nonobese VC workers with high cumulative exposures and normal liver enzymes. Elevated total cytokeratin 18 suggested the presence of necrotic cell death in TASH and may be a useful serologic biomarker. TASH was further characterized by insulin resistance, elevated proinflammatory cytokines, and impaired antioxidant defenses. The threshold VC exposure and the role of other chemical agents in TASH are as yet unknown. (Hepatology 2009.)
Lamivudine Maintenance Beyond One Year After Hbeag Seroconversion Is A Major Factor for Sustained Virologic Response in Hbeag-Positive Chronic Hepatitis B
Authors: Lee Hyun Woong , Lee Heon Ju , Hwang Jae Seok , Sohn Joo Hyun , Jang Jae Young , Han Ki Jun , Park Jun Yong , Kim Do Young , Ahn Sang Hoon , Paik Yong Han , Lee Chun Kyon , Lee Kwan Sik , Chon Chae Yoon , Han Kwang-Hyub
Published: November 2009

The reported durability of virologic response after successful lamivudine monotherapy is variable, and the question remains as to whether virologic responses can be maintained over an extended follow-up period. The aim of this study was to investigate posttreatment durability, the optimal duration of additional treatment after HBeAg clearance or seroconversion, and determinants for sustained virologic response (SVR) following lamivudine monotherapy in patients with HBeAg-positive chronic hepatitis B (CHB). From January 1999 to August 2004, 178 Korean patients with HBeAg-positive CHB were treated with lamivudine and achieved complete responses, defined as a loss of serum HBeAg and hepatitis B virus DNA, and alanine aminotransferase normalization. The mean duration of lamivudine monotherapy was 26 months (range, 12-77). SVR was maintained in 138 patients (77.5%). Host and viral factors were compared between 138 patients with SVR and 40 patients whose response was not sustained. The cumulative relapse rates increased from 15.9% at 1 year to 30.2% at 5 years, with a mean time to relapse after cessation of lamivudine of 12 months (range, 7-42). Most relapses occurred within 2 years after discontinuation of lamivudine (33/40, 82.5%). On multivariate analysis, age ≤40 years and additional treatment for more than 12 months after HBeAg clearance or seroconversion were independent factors for SVR.

Conclusion:

The lamivudine-induced virologic response was durable in patients under 40 years old and those receiving lamivudine for more than 12 months after HBeAg clearance or seroconversion. Age and additional treatment were major predictive factors for SVR. (Hepatology 2010.)
Short-Term Therapy With Peroxisome Proliferation-Activator Receptor-α Agonist Wy-14,643 Protects Murine Fatty Liver Against Ischemia–Reperfusion Injury
Authors: Teoh Narci C. , Williams Jacqueline , Hartley Jennifer , Yu Jun , McCuskey Robert S. , Farrell Geoffrey C.
Published: November 2009

Steatosis increases operative morbidity/mortality from ischemia–reperfusion injury (IRI); few pharmacological approaches have been protective. Using novel genetic/dietary models of nonalcoholic steatohepatitis (NASH) and simple steatosis (SS) in

Alms1

mutant (

foz/foz

) mice, we characterized severity of IRI in NASH versus SS and lean liver and tested our hypothesis that the lipid-lowering effects of the peroxisome proliferation-activator receptor (PPAR)-α agonist Wy-14,643 would be hepatoprotective. Mice were subjected to 60-minute partial hepatic IRI. Microvascular changes were assessed at 15-minute reperfusion by

in vivo

microscopy, injury at 24 hours by serum alanine aminotransferase (ALT), and hepatic necrosis area. Injury and inflammation mediators were determined by way of immunoblotting for intercellular cellular adhesion molecule, vascular cellular adhesion molecule, p38, c-jun N-terminal kinase, IκB-α, interleukin (IL)-1a, IL-12, tumor necrosis factor-α (TNF-α) and IL-6, cell cycle by cyclin D1 and proliferating cell nuclear antigen immunohistochemistry. In

foz/foz

mice fed a high-fat diet (HFD) to cause NASH or chow (SS), IRI was exacerbated compared with HFD-fed or chow-fed wild-type littermates by ALT release; corresponding necrotic areas were 60 ± 22% NASH, 29 ± 9% SS versus 7 ± 1% lean. Microvasculature of NASH or SS livers was narrowed by enormous lipid-filled hepatocytes, significantly reducing numbers of perfused sinusoids, all exacerbated by IRI. Wy-14,643 reduced steatosis in NASH and SS livers, whereas PPAR-α stimulation conferred substantial hepatoprotection against IRI by ALT release, with reductions in vascular cellular adhesion molecule-1, IL-1a, TNF-α, IL-12, activated nuclear factor-κB (NF-κB), p38, IL-6 production and cell cycle entry.

Conclusion:

NASH and SS livers are both more susceptible to IRI. Mechanisms include possible distortion of the microvasculature by swollen fat-laden hepatocytes, and enhanced production of several cytokines. The beneficial effects of Wy-14,643 may be exerted by dampening adhesion molecule and cytokine responses, and activating NF-κB, IL-6 production, and p38 kinase to effect cell cycle entry. (Hepatology 2009.)
Pitfalls of Liver Stiffness Measurement: A 5-Year Prospective Study of 13,369 Examinations
Authors: Castéra Laurent , Foucher Juliette , Bernard Pierre-Henri , Carvalho Françoise , Allaix Daniele , Merrouche Wassil , Couzigou Patrice , de Lédinghen Victor
Published: November 2009

Liver stiffness measurement (LSM) based on transient elastography (TE, FibroScan) is gaining in popularity for noninvasive assessment of liver fibrosis. However, LSM has limitations, which have not yet been thoroughly evaluated. We prospectively investigated the frequency and determinants of LSM failure and unreliable results over a 5-year period, based on 13,369 examinations (134,239 shots). LSM failure was defined as zero valid shots, and unreliable examinations were defined as fewer than 10 valid shots, an interquartile range (IQR)/LSM greater than 30%, or a success rate less than 60%. LSM failure occurred in 3.1% of all examinations (4% at first examination [n = 7261]) and was independently associated at first examination with body mass index (BMI) greater than 30 kg/m2 (odds ratio [OR], 7.5; 95% confidence interval [CI], 5.6-10.2;

P

= 0.0001), operator experience fewer than 500 examinations (OR 2.5 [1.6-4.0];

P

= 0.0001); age greater than 52 years (OR 2.3 [1.6-3.2];

P

= 0.0001), and type 2 diabetes (OR 1.6 [1.1-2.2];

P

= 0.009). Unreliable results were obtained in a further 15.8% of cases (17% at first examination) and were independently associated at first examination with BMI greater than 30 kg/m2 (OR 3.3 [2.8-4.0];

P

= 0.0001), operator experience fewer than 500 examinations (OR 3.1 [2.4-3.9];

P

= 0.0001), age greater than 52 years (OR 1.8 [1.6-2.1];

P

= 0.0001), female sex (OR 1.4 [1.2-1.6],

P

= 0.0001), hypertension (OR 1.3 [1.1-1.5];

P

= 0.003), and type 2 diabetes (OR 1.2 [1.0-1.5];

P

= 0.05). When metabolic syndrome and waist circumference were taken into account in a subgroup of 2835 patients, waist circumference was the most important determinant of LSM failure and unreliable results.

Conclusion:

In our experience, liver stiffness measurements are uninterpretable in nearly one in five cases. The principal reasons are obesity, particularly increased waist circumference, and limited operator experience. These results emphasize the need for adequate operator training and for technological improvements in specific patient subpopulations. (Hepatology 2010.)
Construction of design hyetographs for locations without observed data
Authors: Lin Gwo‐Fong , Wu Ming‐Chang , Chen Guo‐Rong , Liu Shen‐Jung
Published: November 2009

A design hyetograph which represents the time distribution of design rainfall depth corresponding to a duration and a return period is essential in hydrologic design. However, for locations without observed data (ungauged sites), construction of design hyetographs is a difficult task because of the lack of data. Hence, an approach based on self‐organizing map (SOM) is proposed in this paper to construct design hyetographs at ungauged sites. SOM, which is a special kind of artificial neural networks (ANNs), is a powerful technique for extracting and visualizing salient features of data and for solving classification problems. The proposed approach is composed of three steps: classification, assignment and construction. First, the SOM‐based classification is performed to analyse gauged sites' design hyetographs. Second, based on the concept of indicator kriging, a method is developed to assign an ungauged site of interest to a certain cluster. Third, based on the spatial information, the clustering results, and the design hyetographs of gauged sites, the design hyetograph at the site of interest is constructed using the reciprocal‐distance‐squared method. An application is conducted to assess the advantages of the proposed approach over the conventional approaches. Moreover, cross‐validation tests are applied to evaluate the performance of the accuracy and the robustness of the proposed approach. The results confirm the improvement in performance by using the proposed approach instead of conventional approaches. The proposed approach is useful for constructing design hyetographs at ungauged sites. Copyright © 2009 John Wiley & Sons, Ltd.
The effect of focal adhesion kinase gene silencing on 5‐fluorouracil chemosensitivity involves an Akt/NF‐κB signaling pathway in colorectal carcinomas
Authors: Chen Yuying , Wang Zhanxiang , Chang Pingan , Xiang Liuxin , Pan Feng , Li Jianjun , Jiang Jinyan , Zou Lan , Yang Li , Bian Zhiheng , Liang Houjie
Published: November 2009

Multicellular resistance (MCR) is produced because multicellular spheroids (MCSs) are formed with a broad cell–cell connection when cultured in three‐dimensions, which limits the clinical treatment efficacy in solid tumors. Focal adhesion kinase (FAK) plays an important role in apoptosis, survival and cell adhesion between cells and their extracellular matrix. In this study, we investigated the expressions of FAK, Akt and NF‐κB in human colorectal cancer (CRC), and the effects of FAK gene silencing on MCSs formation and 5‐fluorouracil (5‐FU) chemosensitivity in colon carcinoma MCSs culture cells. In CRC samples, FAK, Akt and NF‐κB were overexpressed. The positive expression of FAK correlated notably with lymph node metastasis and cellular differentiation. Positive expressions of Akt and NF‐κB were significantly related to cellular differentiation and lymph node metastasis, respectively. Furthermore, positive expression of FAK correlated with that of Akt and NF‐κB. The expression of FAK was inhibited significantly by a small hairpin RNA targeting FAK. Knockdown of FAK reversed the formation and aggregation of MCSs, significantly decreased the 50% inhibitory concentration of 5‐FU, and markedly increased MCS culture cells apoptosis. These effects were associated with reduced levels of Akt and NF‐κB. These results indicate that suppressing FAK expression potentiated 5‐FU‐induced cytotoxicity and contributed to its chemosensitizing effect by suppressing Akt/NF‐κB signaling in colon carcinoma MCS culture cells. These data also imply that FAK mediates MCR of CRC through the survival signaling pathway FAK/Akt/NF‐κB.
Secretin inhibits cholangiocarcinoma growth via dysregulation of the cAMP‐dependent signaling mechanisms of secretin receptor
Authors: Onori Paolo , Wise Candace , Gaudio Eugenio , Franchitto Antonio , Francis Heather , Carpino Guido , Lee Vien , Lam Ian , Miller Timothy , Dostal David E. , Glaser Shannon S.
Published: November 2009

Secretin plays a key role in the regulation of normal cholangiocyte physiology via secretin receptor (SCTR). SCTR expression is upregulated during extrahepatic cholestasis induced by bile duct ligation and closely associated with cholangiocyte proliferative responses. Although well studied in normal cholangiocytes, the role of secretin and the expression of SCTR in the regulation of cholangiocarcinoma proliferation are unknown. In vitro, secretin (10−7 M) displayed differential effects on normal cholangiocyte [H‐69 and human intrahepatic biliary epithelial cell line (HIBEpiC)] and cholangiocarcinoma (Mz‐ChA‐1, HuH‐28, TFK‐1, SG231, CCLP1 and HuCC‐T1) cell lines as such secretin is mitogenic for normal cholangiocytes and antiproliferative for cholangiocarcinoma. As expected in normal cholangiocytes (HIBEpiC), secretin increased intracellular cyclic adenosine monophosphate (cAMP) levels. However, the effect of secretin on intracellular cAMP levels was suppressed in Mz‐ChA‐1 cells. Secretin‐stimulated intracellular cAMP levels in Mz‐ChA‐1 were restored by pretreatment with pertussis toxin, suggesting that the receptor coupled to Gαi rather than Gαs. SCTR expression was found to be downregulated in 4 of the 6 cholangiocarcinoma cell lines evaluated and in human cholangiocarcinoma biopsy samples. In vivo, secretin significantly inhibited the tumor size and more than doubled tumor latency, which was associated with a decrease in proliferating cell nuclear antigen and an increase in cleaved‐caspase 3 expression levels. Our results demonstrate that secretin and/or the modulation of SCTR expression might have potential as a therapeutic tool in the treatment of cholangiocarcinoma.
Autoantibody potential of cancer therapeutic monoclonal antibodies
Authors: McIntyre John A. , Faulk and W. Page
Published: November 2009

We and others have reported that multiple autoantibodies are unmasked in human polyclonal antibody preparations after exposure to physiological oxidizing agents (hemin) or electromotive force. We now have asked if oxidation unmasks autoantibody reactivities in monoclonal antibodies (mAb). To do this, we have studied 9 FDA approved mAb used therapeutically, including 4 chimeric, 4 humanized and 1 chemically modified chimeric Fab that were exposed to the physiological oxidizing agent hemin at 36°C for 20 hr. These mAb were studied for autoantibody activity to phospholipids and DNA before and after oxidation with hemin and found to develop autoantibody activities after oxidation, while retaining their original specificity as measured by mAb anti‐glycophorin A binding of erythrocytes, CD 19 binding to B lymphocytes and anti‐HLA‐A29 binding to A29‐positive lymphocytes. The finding that certain mAb have the potential to unmask autoantibody activities as a consequence of exposure to physiological redox reactionsin vitrogives pause to our present understanding of the immunological basis of tolerance and concern for potential autoimmune side effects in patients receiving mAb for diagnosis or treatment.
Large Bayesian vector auto regressions
Authors: Bańbura Marta , Giannone Domenico , Reichlin Lucrezia
Published: November 2009

This paper shows that vector auto regression (VAR) with Bayesian shrinkage is an appropriate tool for large dynamic models. We build on the results of De Mol and co‐workers (2008) and show that, when the degree of shrinkage is set in relation to the cross‐sectional dimension, the forecasting performance of small monetary VARs can be improved by adding additional macroeconomic variables and sectoral information. In addition, we show that large VARs with shrinkage produce credible impulse responses and are suitable for structural analysis. Copyright © 2009 John Wiley & Sons, Ltd.
Central and peripheral oxygen transmissibility thresholds to avoid corneal swelling during open eye soft contact lens wear
Authors: Morgan Philip B. , Brennan Noel A. , Maldonado‐Codina Carole , Quhill Walead , Rashid Khaled , Efron Nathan
Published: November 2009

This study was designed to derive central and peripheral oxygen transmissibility (Dk/t) thresholds for soft contact lenses to avoid hypoxia‐induced corneal swelling (increased corneal thickness) during open eye wear. Central and peripheral corneal thicknesses were measured in a masked and randomized fashion for the left eye of each of seven subjects before and after 3 h of afternoon wear of five conventional hydrogel and silicone hydrogel contact lens types offering a range of Dk/t from 2.4 units to 115.3 units. Curve fitting for plots of change in corneal thickness versus central and peripheral Dk/t found threshold values of 19.8 and 32.6 units to avoid corneal swelling during open eye contact lens wear for a typical wearer. Although some conventional hydrogel soft lenses are able to achieve this criterion for either central or peripheral lens areas (depending on lens power), in general, no conventional hydrogel soft lenses meet both the central and peripheral thresholds. Silicone hydrogel contact lenses typically meet both the central and peripheral thresholds and use of these lenses therefore avoids swelling in all regions of the cornea. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Osteotomy of distal radius fracture malunion using a fast remodeling bone substitute consisting of calcium sulphate and calcium phosphate
Authors: Abramo Antonio , Geijer Mats , Kopylov Philippe , Tägil Magnus
Published: November 2009

Malunion after a distal radius fracture can be treated with an osteotomy of the distal radius. Autologous iliac crest bone graft is often used to fill the gap, but the procedure is associated with donor site morbidity. In this study a novel fast resorbing biphasic bone substitute consisting of a mixture of calcium sulphate and calcium phosphate is used (Cerament™ BoneSupport AB, Sweden). Fifteen consecutive patients, with a mean age of 52 (27–71) years were included. All had a malunion after a distal radius fracture and underwent an osteotomy. A fragment specific fixation system, TriMed® (TriMed, Valencia, CA), consisting of a Buttress Pin® and a Radial Pin Plate® were used for fixation and a calcium sulphate and calcium phosphate mixture as bone substitute. The patients were followed for 1 year. Grip strength increased from 61 (28–93)% of the contralateral hand to 85 (58–109)%, p < 0.001. DASH scores decreased from 37 (22–61) to 24 (2–49) p = 0.003. Radiographically all osteotomies healed. An increase of ulnar variance was noted during healing from 1.8 mm immediately postoperatively to 2.6 mm at final follow up. Osteotomy can increase grip strength and decease disability after a malunited fracture. In the present series the bone substitute was replaced by bone, but a minor loss of the achieved radiographic correction was noted in some patients during osteotomy healing. A more rigid fixation may improve the radiographic outcome with this kind of bone substitute. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
The mechanical and biological properties of an injectable calcium phosphate cement‐fibrin glue composite for bone regeneration
Authors: Cui Geng , Li Jie , Lei Wei , Bi Long , Tang Peifu , Liang Yutian , Tao Sheng , Wang Yan
Published: November 2009

Calcium phosphate cement (CPC) that can be injected to form a scaffold in situ has promise for the repair of bone defects. However, its low‐strength limits the CPC to non‐stress‐bearing repairs. Fibrin glue (FG) with good sticking property and biocompatibility is possible used to reinforce the CPC. The objective of this study was to investigate the effects of FG on the mechanical and biological properties of CPC in an injectable CPC‐FG composite. The initial setting time of this CPC‐FG was delayed compared with the CPC control at different powder/liquid (P/L) mass ratio (p > 0.05). At a P/L of 5, the strength was (38.41 ± 4.32) MPa for the CPC‐FG, much higher than (27.42 ± 2.85) MPa for the CPC alone (p < 0.05). SEM showed bone marrow stromal cells (BMSCs) with healthy spreading and anchored on the CPC‐FG composite. After 14 days, the alkaline phosphatase (ALP) activity was (538 ± 33) for the BMSCs on the CPC‐FG and (517 ± 27) for the BMSCs on the CPC alone. Both ALPs were higher than the baseline ALP (93 ± 10) for the undifferentiated BMSCs (p < 0.05). The results demonstrate that this stronger CPC‐FG scaffold may be useful for stem cell‐based bone regeneration in moderate load‐bearing orthopedic applications. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
IL‐6 adsorption dynamics in hemoadsorption beads studied using confocal laser scanning microscopy
Authors: Kimmel Jeremy D. , Gibson Gregory A. , Watkins Simon C. , Kellum John A. , Federspiel William J.
Published: November 2009

Sepsis is characterized by a systemic inflammatory response caused by infection, and can result in organ failure and death. Removal of inflammatory mediators such as cytokines from the circulating blood is a promising treatment for severe sepsis. We are developing an extracorporeal hemoadsorption device to remove cytokines from the blood using biocompatible, polymer sorbent beads. In this study, we used confocal laser scanning microscopy (CLSM) to directly examine adsorption dynamics of a cytokine (IL‐6) within hemoadsorption beads. Fluorescently labeled IL‐6 was incubated with sorbent particles, and CLSM was used to quantify spatial adsorption profiles of IL‐6 within the sorbent matrix. IL‐6 adsorption was limited to the outer 15 μm of the sorbent particle over a relevant clinical time period, and intraparticle adsorption dynamics was modeled using classical adsorption/diffusion mechanisms. A single model parameter, α = qmax
K/D, was estimated by fitting CLSM intensity profiles to our mathematical model, where qmax and K are Langmuir adsorption isotherm parameters, and D is the effective diffusion coefficient of IL‐6 within the sorbent matrix. Given the large diameter of our sorbent beads (450 μm), less than 20% of available sorbent surface area participates in cytokine adsorption. Development of smaller beads may accelerate cytokine adsorption by maximizing available surface area per bead mass. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
In vitro production of polyhydroxyalkanoates: achievements and applications
Authors: Thomson Nicholas , Roy Ipsita , Summers David , Sivaniah Easan
Published: November 2009

The mechanisms of polyhydroxyalkanoate (PHA) production have been studied for over half a century. However, despite numerous improvements in the control of monomer composition, genetically‐engineered host organisms, fermentation strategies and polymer recovery processes they remain uncompetitive compared with petrochemical plastics. Recently, interest has developed in the enzyme‐catalysed production of PHAs in vitro. This has allowed the study of enzyme kinetics and properties, and represents another strategy for the economic production of PHAs on the industrial scale. It also presents an opportunity to coat other materials in thin films of PHA so as to modify the surface properties. In vitro production offers advantages over in vivo methods as it enables greater control over monomer composition and molecular weight, does not require a biomass‐accumulation phase, simplifies downstream processing and can utilise a wider range of monomeric subunits. Copyright © 2009 Society of Chemical Industry
Ultrasound diagnosis of dicephalic conjoined twins at 24 weeks of gestation
Authors: Sabih Durr‐e‐ , Sabih Zahida , Worrall Joseph A. , Khan Ali N.
Published: November 2009

We report the case of dicephalic conjoined twins discovered incidentally on a routine ultrasound at 24 weeks of gestation. There were 2 heads and a neck that fused with 1 thorax, but the spines continued all the way to the coccyx. The spines were connected medially by a fused rib, and laterally, there were ribs that went around the thorax in a more normal fashion. Antenatal ultrasound images are supplemented by postnatal photographs and x‐rays. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
Studies on the synthesis of 4‐oxo‐2,3,4,9‐tetrahydrocarbazole derivatives
Authors: Uzgoren Ayse , Uludag Nesimi , Okay Gurol , Patir Suleyman
Published: November 2009

magnified image

In this study, a new synthetic route for the synthesis of 1‐hydroxy‐4‐oxo‐1,2,3,4‐tetrahydrocarbazole derivatives 12 and 13 from lactone 11 is described. Unfortunately, cyclization of compounds 12 and 13 to their respective azocino[4,3‐b]indole derivatives 14 and 15 was unsuccessful. J. Heterocyclic Chem., (2009).
Enhancing clinical trial design of interventions for posttraumatic stress disorder
Authors: Leon Andrew C. , Davis Lori L.
Published: November 2009

The 2008 Institute of Medicine review of interventions research for posttraumatic stress disorder (PTSD) concluded that new, well‐designed studies are needed to evaluate the efficacy of treatments for PTSD. The Department of Veterans Affairs (VA), the Department of Defense, and the National Institute of Mental Health convened a meeting on research methodology and the VA issued recommendations for design and analysis of randomized controlled clinical trials (RCTs) for PTSD. The rationale that formed the basis for several of the components of the recommendations is discussed here. Fundamental goals of RCT design are described. Strategies in design and analysis that contribute to the goals of an RCT and thereby enhance the likelihood of signal detection are considered.
Reduction‐Sensitive Reversibly Crosslinked Biodegradable Micelles for Triggered Release of Doxorubicin
Authors: Xu Yanmin , Meng Fenghua , Cheng Ru , Zhong Zhiyuan
Published: November 2009

Reduction‐responsive reversibly crosslinked biodegradable micelles were developed and applied for triggered release of doxorubicin (DOX). An amphiphilic block copolymer of poly(ethylene glycol) (PEG) and poly(ε‐caprolactone) (PCL) that contains two lipoyl functional groups at their interface (PEG‐L2‐PCL) has been synthesized. 1H NMR spectroscopy and gel permeation chromatography (GPC) measurements show that the PEG‐L2‐PCL block copolymer had a controlled composition (PEG 5 kDa and PCL 5.4 kDa) and a polydispersity index (PDI) of 1.36. PEG‐L2‐PCL formed micelles with sizes that ranged from 20 to 150 nm in aqueous solutions, wherein a critical micelle concentration (CMC) of 16 mg·L−1 was determined. The micelles were readily crosslinked by adding 7.6 mol % of dithiothreitol (DTT) relative to the lipoyl groups. Notably, micelles after crosslinking demonstrated a markedly enhanced stability against dilution, physiological salt concentration, and organic solvent. In the presence of 10 × 10−3 M DTT, however, micelles were subject to rapid de‐crosslinking. In vitro release studies showed minimal release of DOX from crosslinked micelles at a concentration of 10 mg L−1 (C < CMC, analogous to intravenous injection), wherein less than 15% of the DOX was released in 10 h. In contrast, rapid release of DOX was observed for DOX‐loaded non‐crosslinked micelles under otherwise the same conditions (≈80% release in 0.5 h). In the presence of 10 × 10−3 M DTT mimicking an intracellular reductive environment, sustained release of DOX from crosslinked micelles was achieved, in which 75% of the DOX was released in 9 h. These novel reduction‐sensitive reversibly crosslinked biodegradable micelles are highly promising for targeted intracellular delivery of anticancer drugs.

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Effects of SRB on cathodic protection of Q235 steel in soils
Authors: Sun C. , Xu J. , Wang F.H. , Yu C.K.
Published: November 2009

The effects of sulfate reducing bacteria (SRB) on cathodic protection (CP) of the Q235 steel in the soils have been studied by bacterial analyses, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDX). The results showed that the pH value of the soil around the steel gradually increased, the number of SRB and the corrosion rate of the steel decreased, and the CP efficiency increased with the increasing of applied cathodic potential. At the cathodic polarization potential of −1050 mV, SRB still survived in the soils. At the same potential, the CP efficiency in the soil without SRB was higher than that with SRB, and the corrosion rate of the steel in the soil with SRB was much higher than that without SRB. The cathodic current density applied for the steel in the soil with SRB was bigger than that without SRB at the same cathodic potential.
Electrochemical corrosion behaviors and protective properties of Ni–Co–TiO2 composite coating prepared on sintered NdFeB magnet
Authors: Yang X. K. , Li Q. , Zhang S. Y. , Zhong X. K. , Dai Y. , Luo F.
Published: November 2009

In this paper, a protective Ni–Co–TiO2 composite coating was prepared on the sintered NdFeB magnet by direct current electrodeposition. The surface morphologies, microstructure, and chemical composition of the composite coating were studied using scanning electron microscope (SEM), X‐ray diffraction (XRD), and energy dispersive spectroscopy (EDS), respectively. The surface morphologies and microstructure analysis showed that the composite coating possessed cauliflower‐like grain colonies, and formed face‐centered cubic (fcc) solid solution. The electrochemical corrosion behaviors of the composite coating in 0.5 mol/L H2SO4, 0.6 mol/L NaOH, 0.6 mol/L Na2SO4, and neutral 3.5 wt% NaCl solutions were evaluated by potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS), showing good protection for NdFeB magnet. In order to further investigate the protective properties of the composite coating for NdFeB magnet and the practicability of the composite coating, the long‐term immersion test was carried out in neutral 3.5 wt% NaCl solutions using EIS. The results of long‐term corrosion test showed that the Ni–Co–TiO2 composite coating could provide long‐term protection in neutral 3.5 wt% NaCl solutions for NdFeB magnet.
Homo‐ and Co‐Polymers of Norbornene Containing Aryl‐ and Hetaryl‐Azo Dyes; Synthesis and Sensing Properties
Authors: Abd‐El‐Aziz Alaa S. , Shipman Patrick O. , Shipley Paul R. , Boden Britta N. , Aly Shawkat , Harvey Pierre D.
Published: November 2009

A series of polynorbornene homo‐ and copolymers containing aryl‐ and/or hetaryl‐azo dyes were prepared through ring‐opening metathesis polymerization (ROMP). Thermal studies indicated that the polymers were thermally stable up to 250 °C, and possessed glass transition temperatures ranging from 93 to 133 °C. In THF solutions, the aryl‐azo dye containing homopolymers, displayed λmax = 417 nm while the hetaryl‐azo dye containing homopolymers displayed λmax = 495 nm. The copolymers displayed a λmax that encompassed both the aryl‐ and hetaryl‐azo dye range. The monomers and polymers showed bathochromic shifts in solution when acidified. The polymers were cast into films that changed colour in the presence of both aqueous 1.2 M HCl or HCl(g). The colour change reverses when exposed to aqueous 1.2 M NaOH or NH3(g). This process was repeated several times without disintegration of the polymer film, indicating that these polymers may be useful as reusable acid sensors.

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Synthesis of Polystyrene‐block‐Poly(methyl methacrylate) with Fluorene at the Junction: Sequential Anionic and Controlled Radical Polymerization from a Single Carbon
Authors: Contrella Nathan D. , Tillman Eric S. , Leasure Joshua G. , Monk Ian W.
Published: November 2009

Polystyrene‐block‐poly(methyl methacrylate) (PS‐b‐PMMA) has been synthesized by sequential anionic and reverse atom transfer radical polymerization (ATRP) or a variation of nitroxide mediated polymerization (NMP) from a single initiating site, specifically the 9‐carbon on 2,7‐dibromofluorene or fluorene. The addition of the second arm (PS) relied on thermal decomposition of 2,2′‐azoisobutyronitrile (AIBN) to generate radicals, abstracting the 9‐H on the polymer‐bound fluorene species to form the initiating radical. Styrene was not present in the reaction mixture when AIBN was decomposed, preventing competition between addition across the monomeric alkene and hydrogen abstraction from the fluorene. After 1 h, styrene was introduced and mediation of the subsequent radical polymerization was achieved by the presence of CuCl2/ligand or TEMPO. Characterization of the diblock copolymers by gel permeation chromatography (GPC) revealed substantial shifts in number average molecular weight ($\overline M _{\rm n}$) values compared to the anionically prepared PMMA macroinitiator, while polydispersity indices (PDI's) remained relatively low (typically < 1.5). Characterization by UV detection with GPC (at 310 nm) verified that the diblock polymer is chromophore‐bound, which was further verified by UV‐vis spectroscopy of the isolated diblock.

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Viscoelastic Behavior and Force Nature of Thermo‐Reversible Epoxy Dry Adhesives
Authors: Wang Ruomiao , Xiao Xingcheng , Xie Tao
Published: November 2009

The gecko adhesion phenomenon has stimulated efforts to produce synthetic patterned dry adhesives. Besides introducing surface patterns on dry adhesives, it is also highly desirable to understand their intrinsic material properties. This communication reports the viscoelastic behavior of non‐patterned epoxy elastomers exhibiting intrinsic adhesion that is much higher than that of elastomers typically used for structure patterning. The diverse molecular origin of the adhesion is revealed through the study of adhesion against various substrates.

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Time‐Resolved Electron Spin Resonance Spectroscopy of Radicals Formed During Free Radical Polymerizations of Alkyl Acrylates
Authors: Kajiwara Atsushi
Published: November 2009

Time‐resolved electron spin resonance (TR ESR) spectra allows direct observation of transient radicals (primary propagating radicals) obtained by the addition reaction of a diphenylphosphinoyl radical to acrylates. The addition rate constants (k2) of the diphenylphosphinoyl radical to the acrylates (initiation rate constants) were determined by the monomer concentration dependence of the decay rate of the diphenylphosphinoyl radical. The value of k2 was 1.9 × 107 s−1 · M−1 for the case of t‐butyl acrylate, while the k2 values of ethyl, n‐butyl, 2‐ethylhexyl, and dodecyl acrylates were about 1 × 107 s−1 · M−1. A combination of steady state ESR and TR ESR provided information on the kinetics both of initiation and propagation processes in the radical polymerization of acrylates.

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Safety of influenza vaccination in patients with myasthenia gravis: A population‐based study
Authors: Zinman Lorne , Thoma Jessica , Kwong Jeffrey C. , Kopp Alex , Stukel ThÉRÈSe A. , Juurlink David N.
Published: November 2009

Influenza vaccination has been associated with adverse events including Guillain–Barré syndrome. Because the safety of influenza vaccination in patients with myasthenia gravis (MG) has not been established, some clinicians discourage vaccination for these patients. We explored whether the administration of influenza vaccine to patients with MG might increase the risk of myasthenic crisis. Using population‐based healthcare data from Ontario, Canada, from 1992 to 2007, we utilized the self‐matched, case‐series method of detecting adverse events following vaccination. We studied patients with established myasthenia who were hospitalized for MG within 42 weeks of influenza vaccination. We defined the primary risk interval as the 6 weeks following vaccination. Between January 1, 1992 and March 31, 2006, we identified 3667 hospital admissions for MG. No seasonal trend in MG admissions was evident. In 513 instances, hospitalization occurred within 42 weeks following vaccination in patients previously diagnosed with MG. Among these patients, 266 (52%) were men, the median age was 74 years, and 86 (17%) had previously undergone thymectomy. The estimated relative incidence of admission for MG in the primary risk interval compared with the control interval was 0.84 (95% confidence interval 0.65–1.09). We found similar results in stratified analyses according to gender, age, and thymectomy status. Vaccination of patients with MG against influenza was not found to be associated with exacerbations of the disease. Our findings do not support the practice of withholding influenza vaccination in patients with MG. Muscle Nerve, 2009
Transient three‐dimensional domain decomposition problems: Frame‐indifferent mortar constraints and conserving integration
Authors: Hesch Christian , Betsch Peter
Published: November 2009

The present work deals with transient large‐deformation domain decomposition problems. The tying of dissimilar meshed grids is performed by applying the mortar method. In this connection, a reformulation of the original linear mortar constraints is proposed, which retains frame‐indifference for arbitrary discretizations of the interface. Furthermore, a specific coordinate augmentation technique is proposed to make possible the design of an energy–momentum scheme. Numerical examples demonstrate the robustness and enhanced numerical stability of the newly developed energy–momentum scheme for three‐dimensional problems. Copyright © 2009 John Wiley & Sons, Ltd.
Rejection of persistent‐bounded disturbances in continuous time‐delay systems using observer‐based feedback
Authors: Mahmoud Magdi S. , Saif Abdul‐Wahid
Published: November 2009

In this paper, the problem of persistent‐bounded disturbance rejection of linear continuous‐time systems with time‐varying delays is investigated using the tools of invariant set analysis and Lyapunov‐function methodology. We derive less conservative sufficient conditions on robust attractor for time‐delay systems in terms of strict linear matrix inequalities (LMIs) to guarantee the desired ℒ︁1‐performance. A robust output‐feedback controller is designed and the associated gain is determined using strict LMIs. The developed results are tested on two representative time‐delay examples. Copyright © 2009 John Wiley & Sons, Ltd.
Studies on preparation of HDPE/CB composites including a novel oriented structure by the microwave heating and their characterization
Authors: Zhang Jie , Liu Fanghui , Qian Xinyuan , Lei Yanwei
Published: November 2009

Microwave heating has several advantages over traditional methods of heating, including rapid and uniform heating, greater penetration depth of heat into material, lower power costs and selective heating within the material and so on. In this paper, effects of microwave heating on the properties of high‐density polyethylene/carbon black (HDPE/CB) composites were studied. The results show that the HDPE/CB composites can be heated via microwave irradiation, and composites with different CB concentration exhibit different microwave heatability. The 20 wt% CB composites have the most rapid heating rate, and its temperature reaches 78°C after 10 sec, and 159°C after 150 sec, respectively. Meanwhile, microwave heating improves the mechanical properties of HDPE/CB composites. Scanning Electron Microscopy (SEM) analysis shows a better combination between CB particles and HDPE after microwave irradiation. Furthermore, selective heating of microwave was used to prepare a novel oriented structure, which the core layer has preferential orientation and the surface layer has little orientation. Characterization of the novel oriented structure was also studied. Wide angle X‐ray diffraction (WAXD) analysis of 25 wt% CB composites with the novel oriented structure shows that the diffraction peaks of the surface layer are obviously weaker than those of the core layer, which indicates that orientation in the core layer is more intensive than that in the surface layer. The novel oriented structure is different to the traditional skin‐core structure, in which the surface layer has preferential orientation and the core layer has little orientation. Copyright © 2009 John Wiley & Sons, Ltd.
Photoconductivity of C60‐doping benzocarbazole‐substituted polysiloxanes on an operating wavelength of 633 nm
Authors: Moon In Kyu , Oh Jin‐Woo , Kim Nakjoong
Published: November 2009

A novel polysiloxane having benzo[a]carbazole, benzo[a,i]carbazole, and benzo[a,g]carbazole pendant groups has been synthesized and characterized. We studied the electric‐field‐induced xerographic properties, the photogeneration efficiency, and the photoconductivity of C60‐doping polymeric composites at a wavelength of 633 nm. C60‐doping with benzo[a,g]carbazole‐substituted polysiloxane shows a photogeneration efficiency of 56.55 × 10−5 and a photoconductivity of 52.2 pS/cm at E = 100 V/µm, which was found to be higher than that of the other benzocarbazole‐substituted polysiloxane composites. Copyright © 2009 John Wiley & Sons, Ltd.
Porous composite scaffolds of hydroxyapatite/silk fibroin via two‐step method
Authors: Liu Lin , Liu Jinying , Kong Xiangdong , Cai Yurong , Yao Juming
Published: November 2009

A two‐step method was used to fabricate the hydroxyapatite (HAP)/silk fibroin (SF) scaffolds, i.e. the nano‐sized HAP/SF composite powders were prepared by co‐precipitation, which were then blended with SF solution to fabricate the HAP/SF composite scaffolds. The obtained scaffolds showed a 3D porous structure. The porosity was higher than 90% with the average macropore size of 214.2 µm. Moreover, the nano‐sized HAP/SF composite powders were uniformly dispersed in the silk fibroin matrix, which provided the scaffolds enhanced compressive properties. The cell culture assay showed that the scaffolds fabricated by the two‐step method could improve the cell proliferation and osteogenic differentiation when compared with those prepared by the conventional one‐step blending method. The results suggested that the two‐step method could promote the uniform dispersion of HAP in the SF matrix and efficient combination between the HAP and the matrix, which may provide a potential application in the composite scaffold preparation for tissue engineering. Copyright © 2009 John Wiley & Sons, Ltd.
The role of interferons in the treatment of osteosarcoma
Authors: Whelan Jeremy , Patterson Daniel , Perisoglou Martha , Bielack Stefan , Marina Neyssa , Smeland Sigbjorn , Bernstein Mark
Published: November 2009

Interferons, a group of cytokines with antiangiogenic, direct antitumour and immunostimulating properties, have shown significant activity against osteosarcoma in vitro and in xenograft models. They have also been used in osteosarcoma clinical trials as a single adjuvant to surgery, with an apparent increase in relapse‐free survival. In the ongoing EURAMOS 1 clinical trial, interferon α‐2b is evaluated as an adjuvant treatment in osteosarcoma. This article reviews the rationale for the use of interferon in cancer with special reference to the treatment of osteosarcoma, including all published data of clinical efficacy in this disease. Pediatr Blood Cancer 2010;54:350–354. © 2009 Wiley‐Liss, Inc.