bluuebunny/crossref_metadata_2025 huggingface dataset:
Toxicity and uptake of TRI- and dibutyltin in Daphnia magna in the absence and presence of nano-charcoal
Authors: Fang Liping , Borggaard Ole K , Holm Peter E , Hansen Hans Christian Bruun , Cedergreen Nina
Published: August 2011

Butyltins (BTs), such as tributyltin (TBT) and dibutyltin (DBT), are toxic to aquatic organisms, but the presence of the strong adsorbent, black carbon (BC), can markedly influence BT toxicity and uptake in organisms. In the present study, the acute toxicity and uptake of TBT and DBT in the crustacean, Daphnia magna, were investigated with and without addition of nano-charcoal at different pHs and water hardnesses. The results showed that the toxicity of TBT and DBT increased by lowering the pH from 8 to 6. This reflects a relatively higher toxicity of cationic BT species than of the neutral species. At pH 6, by enhancing the water hardness of the media from 0.6 to 2.5 mM, the toxicity of TBT and DBT consistently decreased due to competitive binding of bivalent cations (Mg2+, Ca2+) to biotic ligands of D. magna. Furthermore, the toxicity of TBT to D. magna significantly decreased in the presence of nano-charcoal compared with experiments without nano-charcoal at pH 6 and 8, while no significant decrease in toxicity of DBT was observed in the presence of nano-charcoal. This can be attributed to the insignificant decrease of free DBT concentration in the presence of nano-charcoal compared with that for TBT. Conversely, it was observed that more TBT and DBT were taken up in D. magna in the presence of nano-charcoal due to the uptake of TBT or DBT associated with nano-charcoal by Daphnia in gut systems, as seen by light microscopy. This indicated that only free nonadsorbed BTs were toxic to D. magna, at least during short periods of exposure. Environ. Toxicol. Chem. 2011;30:2553–2561. © 2011 SETAC
Proteomic identification of novel targets regulated by the mammalian target of rapamycin pathway during oligodendrocyte differentiation
Authors: Tyler William A. , Jain Mohit Raja , Cifelli Stacey E. , Li Qing , Ku Li , Feng Yue , Li Hong , Wood Teresa L.
Published: August 2011

Previous work from our laboratory demonstrated that the mammalian target of rapamycin (mTOR) is active during and required for oligodendrocyte progenitor cell (OPC) differentiation. Here, we applied an iTRAQ mass spectrometry‐based proteomic approach to identify novel targets of the mTOR pathway during OPC differentiation. Among the 978 proteins identified in this study, 328 (34%) exhibited a greater than 20% change (P < 0.05) in control versus rapamycin‐treated cultures following 4 days of differentiation in vitro. Interestingly, 197 (20%) proteins were elevated in rapamycin‐treated cultures, while 131 (13%) proteins were downregulated by rapamycin. In support of our previous data, inhibiting mTOR caused a dramatic reduction in the expression of myelin proteins. mTOR also was required for the induction of proteins involved in cholesterol and fatty acid synthesis, as well as the expression of many cytoskeletal proteins, cell signaling components, and nuclear/transcriptional regulators. Of particular interest was the identification of several critical mediators of oligodendrocyte differentiation. Specifically, mTOR activity controls the developmentally programmed upregulation of the prodifferentiation factors Fyn and Quaking, whereas the expression of the differentiation repressor Gpr17 was elevated by mTOR inhibition. These data reveal a distinct signature of mTOR‐regulated protein expression during OPC differentiation. © 2011 Wiley‐Liss, Inc.
In vitro modeling of central nervous system myelination and remyelination
Authors: Jarjour Andrew A. , Zhang Hui , Bauer Nina , ffrench‐Constant Charles , Williams Anna
Published: August 2011

This review aims to summarize the current techniques to study myelination and remyelination in culture systems. We attempt to put these into historical context, and to identify the strengths and weaknesses of each approach, which vary depending on the experimental question to be tested. We discuss the difficulty and importance of quantification of myelination and in particular remyelination. Finally, we provide our predictions of how these techniques will and should develop in the future. © 2011 Wiley Periodicals, Inc.
Burden of Cirrhosis on Older Americans and Their Families
Authors: Rakoski Mina O. , McCammon Ryan J. , Piette John D. , Iwashyna Theodore J. , Marrero Jorge A. , Lok Anna S. , Langa Kenneth M. , Volk Michael L.
Published: August 2011

Prevalence of cirrhosis among older adults is expected to increase; therefore, we studied the health status, functional disability, and need for supportive care in a large national sample of individuals with cirrhosis. A prospective cohort of individuals with cirrhosis was identified within the longitudinal, nationally representative Health and Retirement Study. Cirrhosis cases were identified in linked Medicare data via ICD–9–CM (International Classification of Diseases, Ninth Revision, Clinical Modification) codes and compared to an age–matched cohort without cirrhosis. Two primary outcome domains were assessed: (1) patients' health status (perceived health status, comorbidities, health care utilization, and functional disability as determined by activities of daily living and instrumental activities of daily living), and (2) informal caregiving (hours of caregiving provided by a primary informal caregiver and associated cost). Adjusted negative binomial regression was used to assess the association between cirrhosis and functional disability. A total of 317 individuals with cirrhosis and 951 age–matched comparators were identified. Relative to the comparison group, individuals with cirrhosis had worse self–reported health status, more comorbidities, and used significantly more health care services (hospitalizations, nursing home stays, physician visits;

P

< 0.001 for all bivariable comparisons). They also had greater functional disability (

P

< 0.001 for activities of daily living and instrumental activities of daily living), despite adjustment for covariates such as comorbidities and health care utilization. Individuals with cirrhosis received more than twice the number of informal caregiving hours per week (

P

< 0.001), at an annual cost of US $4700 per person.

Conclusion:

Older Americans with cirrhosis have high rates of disability, health care utilization, and need for informal caregiving. Improved care coordination and caregiver support is necessary to optimize management of this frail population. (Hepatology 2012;55:184–191)
Higher serum testosterone is associated with increased risk of advanced hepatitis C–related liver disease in males
Authors: White Donna L. , Tavakoli-Tabasi Shariar , Kuzniarek Jill , Pascua Rhia , Ramsey David J. , El-Serag Hashem B.
Published: August 2011

Males have strikingly increased risk of advanced liver disease. However, the association between testosterone and risk of hepatitis C virus (HCV)-related advanced liver disease is unknown. We performed a cross-sectional study in male veterans with chronic HCV. Blood samples were obtained to measure total serum testosterone and perform the FibroSURE-ActiTest. Other risk-factor data were obtained through systematic questionnaires (e.g., alcohol), physical measurements (e.g., body mass index), and serological tests (e.g., viral load). The association between total testosterone and risk of advanced hepatic fibrosis (F3 and F3/F4) and inflammatory activity (A3 and A2/3) measured by the FibroSURE-ActiTest was evaluated with logistic regression. A total of 308 eligible study participants were prospectively recruited (mean age: 57; 52% African-American). There were 105 cases with advanced fibrosis and 203 mild fibrosis controls as well as 88 cases with advanced inflammatory activity and 220 mild activity controls. Mean total serum testosterone was significantly higher in advanced fibrosis cases as well as advanced inflammatory activity cases, compared to mild disease controls (6.0 versus 5.3 ng/mL and 5.9 versus 5.4 ng/mL, respectively). We observed a significant 25% increase in advanced fibrosis risk and 15% increase in advanced inflammatory activity risk for each 1-ng/mL increase in total serum testosterone. Total testosterone in the upper tertile was associated with an even greater excess risk of advanced fibrosis than advanced inflammatory activity (odds ratio [OR]adjusted advanced fibrosis = 3.74; 95% CI: 1.86-6.54 versus ORadjusted advanced inflammatory activity = 2.23; 95% CI: 1.07-4.93, respectively).

Conclusions :

Total serum testosterone is associated with an increased risk of both advanced hepatic fibrosis and advanced hepatic inflammatory activity in HCV-infected men. Testosterone may be important in the pathogenesis of HCV-related advanced liver disease in males.
Effects of hypolipidemic agent nordihydroguaiaretic acid on lipid droplets and hepatitis C virus
Authors: Syed Gulam H. , Siddiqui Aleem
Published: August 2011

Hepatitis C virus (HCV) relies on host lipid metabolic pathways for its replication, assembly, secretion, and entry. HCV induces

de novo

lipogenesis, inhibits β-oxidation, and lipoprotein export resulting in a lipid-enriched cellular environment critical for its proliferation. We investigated the effects of a hypolipidemic agent, nordihydroguaiaretic acid (NDGA), on host lipid/fatty acid synthesis and HCV life cycle. NDGA negated the HCV-induced alteration of host lipid homeostasis. NDGA decreased sterol regulatory element binding protein (SREBP) activation and enhanced expression of genes involved in β-oxidation. NDGA inhibited very low-density lipoprotein (VLDL) secretion by affecting mediators of VLDL biosynthesis. Lipid droplets (LDs), the neutral lipid storage organelles, play a key role in HCV morphogenesis. HCV induces accumulation and perinuclear distribution of LDs, whereas NDGA most notably reduced the overall number and increased the average size of LDs. The antiviral effects of NDGA resulted in reduced HCV replication and secretion.

Conclusion:

NDGA-mediated alterations of host lipid metabolism, LD morphology, and VLDL transport appear to negatively influence HCV proliferation. (Hepatology 2011;)
Response of murine bone marrow‐derived mesenchymal stromal cells to dry‐etched porous silicon scaffolds
Authors: Hajj‐Hassan Mohamad , Khayyat‐Kholghi Maedeh , Wang Huifen , Chodavarapu Vamsy , Henderson Janet E.
Published: August 2011

Porous silicon shows great promise as a bio‐interface material due to its large surface to volume ratio, its stability in aqueous solutions and to the ability to precisely regulate its pore characteristics. In the current study, porous silicon scaffolds were fabricated from single crystalline silicon wafers by a novel xenon difluoride dry etching technique. This simplified dry etch fabrication process allows selective formation of porous silicon using a standard photoresist as mask material and eliminates the post‐formation drying step typically required for the wet etching techniques, thereby reducing the risk of damaging the newly formed porous silicon. The porous silicon scaffolds supported the growth of primary cultures of bone marrow derived mesenchymal stromal cells (MSC) plated at high density for up to 21 days in culture with no significant loss of viability, assessed using Alamar Blue. Scanning electron micrographs confirmed a dense lawn of cells at 9 days of culture and the presence of MSC within the pores of the porous silicon scaffolds. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.
Development and characterization of an acellular porcine cartilage bone matrix for use in tissue engineering
Authors: Kheir Ehab , Stapleton Thomas , Shaw David , Jin Zhongmin , Fisher John , Ingham Eileen
Published: August 2011

The aim of this study was to develop a technique to decellularize a porcine cartilage bone construct with view to using this as a biological scaffold for cartilage substitution. The decellularization protocol applied freeze/thaw cycles; this was followed by cyclic incubation in hypotonic tris buffer and 0.1% (w/v) sodium dodecyl sulfate in hypotonic buffer plus protease inhibitors. Nucleases (RNase and DNase) were used to digest nucleic acids followed by disinfection using 0.1% (v/v) peracetic acid. Histological analysis confirmed the absence of visible cells within the decellularized tissue. DNA analysis revealed the near‐complete removal of genomic DNA from the decellularized tissues. The decellularization process had minimal effect on the collagen content of the cartilage. However, there was a significant reduction in the glycosaminoglycan content in the decellularized tissues. There was no evidence of the expression of the major xenogeneic epitope, galactose‐α‐1,3‐galactose. Biomechanical indentation testing of decellularized tissues showed a significant change in comparison to the fresh cartilage. This was presumed to be caused by the reduction in the glycosaminoglycan content. Biocompatibility of the acellular scaffold was determined using contact cytotoxicity assays and a galactosyltransferase knockout mouse model. Decellularized porcine cartilage tissue was found to exhibit favorable compatibility in both in vitro and in vivo tests. In conclusion, this study has generated data on the production of an acellular cartilage bone matrix scaffold for use in osteochondral defect repair. To our knowledge, this is the first study that has successfully removed whole cells and α‐gal from xenogeneic cartilage and bone tissue. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Effects of TiO2‐containing phosphate glasses on solubility and in vitro biocompatibility
Authors: Novajra G. , Vitale‐Brovarone C. , Knowles J. C. , Maina G. , Aina V. , Ghigo D. , Bergandi L.
Published: August 2011

Phosphate‐based glasses with different amounts of titanium dioxide (TiO2), having the following molar composition 50P2O5‐30CaO‐9Na2O‐3SiO2‐3MgO‐(5‐x)K2O‐xTiO2, (where x = 0, 2.5, 5 mol %), were synthesised and characterized in terms of solubility (according to ISO 10993‐14), and in vitro biocompatibility using human MG‐63 osteoblast cells. Dissolution tests were carried out in Tris‐HCl (pH 7.4) to simulate the physiological pH and in citric acid (pH 3.0) to simulate an acidic environment. The weight loss decreased with increasing TiO2 content, a process further enhanced in acidic medium. TiO2 reduced the pH changes usually caused by the dissolution products released. Cellular tests showed that all the glasses studied (0–5 mol % TiO2) and TiCl4, used to investigate the biocompatibility of titanium ions, did not produce cytotoxic effects on human MG‐63 osteoblasts for up to 5 days in culture. On the basis of these results, we suggest that TiO2‐containing phosphate glasses could be promising substrates for bone tissue engineering applications. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.
The photoreceptive cells of the pineal gland in adult zebrafish (Danio rerio)
Authors: Laurà Rosaria , Magnoli Domenico , Zichichi Rosalia , Guerrera Maria Cristina , De Carlos Felix , Suárez Alberto Álvarez , Abbate Francesco , Ciriaco Emilia , Vega Jose Antonio , Germanà Antonino
Published: August 2011

The zebrafish pineal gland plays a fundamental role in the regulation of the circadian rhythm through the melatonin secretion. The pinealocytes, also called photoreceptive cells, are considered the morphofunctional unit of pineal gland. In literature, the anatomical features, the cellular characteristics, and the pinealocytes morphology of zebrafish pineal gland have not been previously described in detail. Therefore, this study was undertaken to analyze the structure and ultrastructure, as well as the immunohistochemical profile of the zebrafish pineal gland with particular reference to the pinealocytes. Here, we demonstrated, using RT‐PCR, immunohistochemistry and transmission electron microscopy, the expression of the mRNA for rhodopsin in the pineal gland of zebrafish, as well as its cellular localization exclusively in the pinealocytes of adult zebrafish. Moreover, the ultrastructural observations demonstrated that the pinealocytes were constituted by an outer segment with numerous lamellar membranes, an inner segment with many mitochondria, and a basal pole with the synapses. Our results taken together demonstrated a central role of zebrafish pinealocytes in the control of pineal gland functions. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
Polycyclic N‐heterocyclic compounds, part 67: Reaction of 6,7‐substituted N‐(quinazolin‐4‐yl)amidine derivatives with hydroxylamine hydrochloride: Formation of in vitro inhibitors of pentosidine
Authors: Okuda Kensuke , Muroyama Hideki , Hirota Takashi
Published: August 2011

Reactions of N‐(quinazolin‐4‐yl)amidines and their amide oximes with hydroxylamine hydrochloride gave cyclization products that were formed by an initial ring cleavage of the pyrimidine component followed by a ring closure formation of 1,2,4‐oxadiazole to give N‐[2‐([1,2,4]oxadiazol‐5‐yl)phenyl]formamide oximes. All isolated products were evaluated for in vitro inhibitory activity on the formation of pentosidine, which is one of representative advanced glycation end products. Some products exhibited significant inhibitory activity against pentosidine formation. J. Heterocyclic Chem., (2011).
One‐pot synthesis of 2,3‐disubstituted‐2,3‐dihydroquinazolin‐4(1H)‐ones using [Hmim][NO3]: An eco‐friendly protocol
Authors: Mohammadpoor‐Baltork Iraj , Khosropour Ahmad Reza , Moghadam Majid , Tangestaninejad Shahram , Mirkhani Valiollah , Soltani Mohammad , Mirjafari Arsalan
Published: August 2011

An efficient method for the synthesis of a series of 2,3‐disubstituted‐2,3‐dihydroquinazolin‐4(1H)‐ones is described via one‐pot condensation reaction of isatoic anhydride, aryl aldehydes, and primary amines using a Brønsted acidic ionic liquid, [Hmim][NO3], as a catalyst and medium. The present protocol enjoys convenient reaction and simple work‐up, greenness, short reaction times, and reusable catalyst as well as mild reaction conditions. J. Heterocyclic Chem., (2011).
Effect of implantation site and injury condition on host response to human‐derived fascia lata ECM in a rat model
Authors: Leigh Diane R. , Baker Andrew R. , Mesiha Mena , Rodriguez E. Rene , Tan Carmela D. , Walker Esteban , Derwin Kathleen A.
Published: August 2011

The host response and remodeling of ECM scaffolds are believed to be critical determinants of success or failure in repair or reconstructive procedures. Host response has been investigated in subcutaneous or abdominal wall implantation models. The extent to which evaluation of the host response to ECM intended for tendon or ligament repair should be performed in an orthotopic site is not known. This study compared the host response to human‐derived fascia lata ECM among various implantation sites in the rat model. Results showed that a xenograft in the rat shoulder does not exhibit a different host response at 7 days from xenograft in the body wall, suggesting that either site may be appropriate to study the early host response to biologic grafts as well as the effect of various treatments aimed to modify the early host response. By 28 days, a xenograft in the rat shoulder does elicit a unique host response from that seen in the body wall. Therefore, it may be more appropriate to use an orthotopic shoulder model for investigating the long‐term host response and remodeling of biologic grafts to be used for rotator cuff repair. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:461–467, 2012
Suture anchor versus screw fixation for greater tuberosity fractures of the humerus—a biomechanical study
Authors: Lin Cheng‐Li , Hong Chih‐Kai , Jou I‐Ming , Lin Chii‐Jeng , Su Fong‐Chin , Su Wei‐Ren
Published: August 2011

Suture anchors and screws are commonly used for fixation of humeral greater tuberosity (GT) fractures in either arthroscopic or open surgeries, but no biomechanical studies have been performed to compare the strength of fixation constructs using these two implants. This cadaveric study aimed to compare the biomechanical strength of three different fixation constructs in the management of GT fractures: Double‐Row Suture Anchor Fixation (DR); Suture‐Bridge Technique using suture anchors and knotless suture anchors (SB); and Two‐Screw Fixation (TS). The experimental procedure was designed to assess fracture displacement after cyclic loading, failure load, and failure mode of the fixation construct. Significant differences were found among the SB (321 N), DR (263 N), and TS (187 N) groups (SB > DR > TS, p < 0.05) in the mean force of cyclic loading to create 3 mm displacement. Regarding the mean force of cyclic loading to create 5 mm displacement and ultimate failure load, no significant difference was found between the DR (370 N, 480 N) and SB (399 N, 493 N) groups, but both groups achieved superior results compared with the TS group (249 N, 340 N) (p < 0.05). The results suggested that the suture anchor constructs would be stronger than the fixation construct using screws for the humeral GT fracture. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:423–428, 2012
Kinetics of basic hydrolysis of tris(1,10‐phenanthroline)iron(II) in macromolecular assemblies of CTAB
Authors: Mandal Harasit Kumar , Majumdar Tapas , Mahapatra Ambikesh
Published: August 2011

The kinetics of basic hydrolysis of tris(1,10‐phenanthroline)iron(II) has been carried out in aqueous, N‐cetyl‐N,N,N‐trimethyl ammonium bromide (CTAB) micellar, and CTAB reverse micellar media by UV–visible spectroscopy system. The reaction follows the overall second‐order kinetics; first order in each Fe(II) complex and the base (−OH). CTAB micelles catalyze the reaction rate through the adsorption of the Fe(II) complex and the hydroxyl ions on the micellar surface. In the reverse micellar medium, interesting physicochemical features are observed. Being ionic nature of reactants, both the reactants prefer to stay and react inside the water pool in place of the hydrophobic environment. The rate increases with w, that is, the size of the water pool, attains a maximum value at w = 8.33, and then decreases. But the rate increases as the concentration of surfactant increases at fixed w values. For a better explanation of the kinetic data, the activation parameters, standard enthalpy of activation (Δ‡H°), standard entropy of activation (Δ‡S°), and energy of activation (Ea) were determined. All kinetic data corroborate the proposed mechanism. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 579–589, 2011
Theoretical study of the mechanism for the gas‐phase pyrolysis kinetics of 2‐methylbenzyl chloride
Authors: Marquez Edgar , Mora Jose R. , Cordova Tania , Chuchani Gabriel
Published: August 2011

The study of the kinetics and mechanism of dehydrochlorination reaction of 2‐methyl benzyl chloride in the gas phase was carried out by means of electronic structure calculations using ab initio Móller‐Plesset MP2/6‐31G(d,p), and Density Functional Theory (DFT) methods: B3LYP/6‐31G(d,p), B3LYP/6‐31++G(d,p), MPW1PW91/6‐31G(d,p), MPW1PW91/6‐31++G(d,p)], PBE/6‐31G(d,p), PBE/6‐31++G(d,p). Investigated reaction pathways comprise: Mechanism I, a concerted reaction through a six‐centered cyclic transition state (TS) geometry; Mechanism II, a 1,3‐chlorine shift followed by beta‐elimination and Mechanism III, a single‐step elimination with simultaneous HCl and benzocyclobutene formation through a bicyclic type of TS. Calculated parameters ruled out Mechanism III and suggest the elimination reaction may occur by either unimolecular Mechanism I or Mechanism II. However, the TS of the former is 20 kJ/mole more stable than the TS of the latter. Consequently, the Mechanism I seem to be more probable to occur. The rate‐determining process is the breaking of C‐Cl bond. The involvement of π‐electrons of the aromatic system was demonstrated by NBO charges and bond order calculations. The reaction is moderately polar in nature. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 537–546, 2011
Toward optimizing the indications for orthotopic liver transplantation in hepatocellular carcinoma
Authors: Samuel Didier , Colombo Massimo , El-Serag Hachem , Sobesky Rodolphe , Heaton Nigel
Published: August 2011

Key Points

1. Liver transplantation is currently an effective therapy for patients with HCC who meet the Milan criteria.

2. The proportion of patients on waiting lists for liver transplantation who have HCC has increased substantially in recent years. HCC is currently one of the major indications for liver transplantation; it is the indication for approximately one-third of liver transplants.

3. If the Milan criteria are not met, the survival rates after liver transplantation for HCC tend to decrease, mainly because of the catastrophic consequences of HCC recurrence.

4. A few studies have supported liver transplantation when the Milan criteria are exceeded, but extensions beyond the Milan criteria remain controversial. Even if an individual patient with HCC who does not meet the Milan criteria might benefit from liver transplantation, the limited number of currently available donor organs limits the indications for liver transplantation to those patients with HCC who have the greatest likelihood of survival after the procedure.

5. To patients with early-stage HCC, surgical resection can be offered if the hepatocellular function is well maintained and severe portal hypertension is not present.

6. To enable patients with HCC to have access to liver transplantation that is similar to the access for other patients without HCC in the MELD allocation system, additional points based on the number and size of HCC lesions are assigned to patients on the waiting list. However, this system requires further refinement to ensure that it is as fair as possible.

7. Liver transplantation for HCC should be restricted to those patients who are expected to have the same posttransplant survival as that of patients with nonneoplastic end-stage chronic liver disease.

8. On the basis of these considerations, a 5-year survival rate of 50% after liver transplantation for HCC seems too low. Liver Transpl, 2011. © 2011 AASLD.
Fast diffusion‐weighted steady state free precession imaging of in vivo knee cartilage
Authors: Bieri O. , Ganter C. , Welsch G. H. , Trattnig S. , Mamisch T. C. , Scheffler K.
Published: August 2011

Quantification of molecular diffusion with steady state free precession (SSFP) is complicated by the fact that diffusion effects accumulate over several repetition times (TR) leading to complex signal dependencies on transverse and longitudinal magnetization paths. This issue is commonly addressed by setting TR > T2, yielding strong attenuation of all higher modes, except of the shortest ones. As a result, signal attenuation from diffusion becomes T2 independent but signal‐to‐noise ratio (SNR) and sequence efficiency are remarkably poor. In this work, we present a new approach for fast in vivo steady state free precession diffusion‐weighted imaging of cartilage with TR << T2 offering a considerable increase in signal‐to‐noise ratio and sequence efficiency. At a first glance, prominent coupling between magnetization paths seems to complicate quantification issues in this limit, however, it is observed that diffusion effects become rather T2(ΔD ∼ 1/10 ΔT2) but not T1 independent (ΔD ∼ 1/2 ΔT1) for low flip angles α ∼ 10 − 15°. As a result, fast high‐resolution (0.35 × 0.35 − 0.50 × 0.50 mm2 in‐plane resolution) quantitative diffusion‐weighted imaging of human articular cartilage is demonstrated at 3.0 T in a clinical setup using estimated T1 and T2 or a combination of measured T1 and estimated T2 values. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
A revision of the intensity of treatment rating scale: Classifying the intensity of pediatric cancer treatment
Authors: Kazak Anne E. , Hocking Matthew C. , Ittenbach Richard F. , Meadows Anna T. , Hobbie Wendy , DeRosa Branlyn Werba , Leahey Ann , Kersun Leslie , Reilly Anne
Published: August 2011

Background

We previously developed a reliable and valid method for classifying the intensity of pediatric cancer treatment. The Intensity of Treatment Rating Scale (ITR‐2.0) 1 classifies treatments into four operationally defined levels of intensity and is completed by pediatric oncology specialists based on diagnosis, stage, and treatment data from the medical record. Experience with the ITR‐2.0 and recent changes in treatment protocols indicated the need for a minor revision and revalidation.

Methods

Five criterion raters reviewed the prior items, independently proposing additions and/or changes in the classification of diseases/treatments. Subsequent to a group discussion of the proposed changes, a revised 43‐item ITR was evaluated. Pediatric oncologists (n = 47) completed a two‐part online questionnaire. Validity of the classifications was determined by the oncologists classifying each disease/treatment into one of the four levels of intensity. Inter‐rater reliability was calculated by having each oncologist classify the treatments of 12 sample patients using the new version which we call the ITR‐3.

Results

Agreement between median ratings of the 43 items for the pediatric oncologists and the criterion raters was high (r = 0.88). The median of the raters was either identical (81%) with the criterion ratings or discrepant by one level. Inter‐rater reliability was very high when using the ITR‐3 to classify 12 sample patients, with a median agreement of 0.90 and an intraclass correlation coefficient (rICC = 0.86).

Conclusions

With these minor modifications and updates, the ITR‐3 remains a reliable and valid method for classifying pediatric oncology treatment protocols. Pediatr Blood Cancer 2012; 59: 96–99. © 2011 Wiley Periodicals, Inc.
A Thin‐layer Chromatography Method for the Identification of Three Different Olibanum Resins (Boswellia serrata, Boswellia papyrifera and Boswellia carterii, respectively, Boswellia sacra)
Authors: Paul Michael , Brüning Gerit , Bergmann Jochen , Jauch Johann
Published: August 2011

Introduction

Resins of the genus Boswellia are currently an interesting topic for pharmaceutical research since several pharmacological activities (e.g. anti‐inflammatory, anti‐microbial, anti‐tumour) are reported for extracts and compounds isolated from them. Unambiguous identification of these resins, by simple and convenient analytical methods, has so far not clearly been verified.

Objective

For differentiation and identification of three important Boswellia species (Boswellia serrata Roxb., Boswellia papyrifera Hochst. and Boswellia carterii Birdw., respectively Boswellia sacra Flueck.), possible even for minimally equipped laboratories, a thin‐layer chromatography (TLC) method was developed, allowing unambiguous identification of the three species.

Methodology

Crude resin samples (commercial samples and a voucher specimen) were extracted with methanol or diethyl ether and subjected to TLC analysis (normal phase). A pentane and diethyl ether (2:1) with 1% acetic acid eluent was used. Chromatograms were analysed by UV detection (254 nm) and dyeing with anisaldehyde dyeing reagent. Significant spots were isolated and structures were assigned (mass spectrometry; nuclear magnetic resonance spectroscopy).

Results

Incensole and incensole acetate are specific biomarkers for Boswellia papyrifera. Boswellia carterii/Boswellia sacra reveal ß‐caryophyllene oxide as a significant marker compound. Boswellia serrata shows neither incensole acetate nor ß‐caryophyllene oxide spots, but can be identified by a strong serratol and a sharp 3‐oxo‐8,24‐dien‐tirucallic acid spot.

Conclusion

The TLC method developed allows unambiguous identification of three different olibanum samples (Boswellia papyrifera, Boswellia serrata, Boswellia carterii/Boswellia sacra). Evidence on the specific biosynthesis routes of these Boswellia species is reported. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis of a new multiarm star polymer based on hyperbranched poly(styrene) core and poly(ε‐caprolactone) arms and its use as reactive modifier of epoxy thermosets
Authors: Morell Mireia , Foix David , Lederer Albena , Ramis Xavier , Voit Brigitte , Serra Àngels
Published: August 2011

A well‐defined multiarm star copolymer poly(styrene)‐b‐poly(ε‐caprolactone) (PSOH‐b‐PCL) with an average number of PCL arms per molecule of 60 has been prepared. 4‐Chloromethyl styrene (4‐CMS) was polymerized by means of atom transfer radical polymerization (ATRP) to obtain a hyperbranched poly(styrene) with chlorines as terminal groups. Subsequently, chlorines were substituted by reaction with diisopropanolamine (DIPA) to give the hydroxyl‐ended derivative. Finally, the hydroxyl‐ended hyperbranched poly(styrene) has been used as a macroinitiator core to polymerize ε‐caprolactone by means of cationic ring‐opening polymerization so as to obtain the star copolymer. In a second step, PSOH‐b‐PCL was used as reactive modifier of diglycidylether of bisphenol A formulations cured by 1‐methyl imidazole (1‐MI) obtaining nanostructured thermosets. The curing process was studied by dynamic scanning calorimetry and Fourier transform infrared spectroscopy (FTIR). By rheometry, the effect of this new polymer topology on the complex viscosity (η*) of the reactive mixture and on the gelation process was also analyzed. The thermomechanical characteristics of the modified materials were determined. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Computational analysis of residue contributions to coiled‐coil topology
Authors: Ramos Jorge , Lazaridis Themis
Published: August 2011

A variety of features are thought to contribute to the oligomeric and topological specificity of coiled coils. In previous work, we examined the determinants of oligomeric state. Here, we examine the energetic basis for the tendency of six coiled‐coil peptides to align their α‐helices in antiparallel orientation using molecular dynamics simulations with implicit solvation (EEF1.1). We also examine the effect of mutations known to disrupt the topology of these peptides. In agreement with experiment, ARG or LYS at a or d positions were found to stabilize the antiparallel configuration. The modeling suggests that this is not due to a–a′ or d–d′ repulsions but due to interactions with e′ and g′ residues. TRP at core positions also favors the antiparallel configuration. Residues that disfavor parallel dimers, such as ILE at d, are better tolerated in, and thus favor the antiparallel configuration. Salt bridge networks were found to be more stabilizing in the antiparallel configuration for geometric reasons: antiparallel helices point amino acid side chains in opposite directions. However, the structure with the largest number of salt bridges was not always the most stable, due to desolvation and configurational entropy contributions. In tetramers, the extent of stabilization of the antiparallel topology by core residues is influenced by the e′ residue on a neighboring helix. Residues at b and c positions in some cases also contribute to stabilization of antiparallel tetramers. This work provides useful rules toward the goal of designing coiled coils with a well‐defined and predictable three‐dimensional structure.
Transport Coefficients of Eucalyptol through Various Polymeric Films
Authors: Leelaphiwat Pattarin , Chonhenchob Vanee , Singh Sher Paul , Kruenate Jittiporn , Wichai Uthai , Ong Peter K. C.
Published: August 2011

This study presents the determination of the transport properties of eucalyptol, which is a key aroma compound in fresh tropical herbs through different polymeric packaging materials. Packaging films used in this study were polyethylene, polypropylene, Nylon, polyethylene terephthalate and polylactide (PLA1 and PLA2). Test films were immersed in the 1000 ppm of aroma compound and stored in amber vials. The concentrations of aroma compounds extracted from films were determined using gas chromatography. Diffusion, solubility, permeability and partition coefficients were calculated from sorption kinetics. Results show that the diffusion and solubility coefficients of eucalyptol were lowest in PLA1 and highest in polyethylene. Solubility coefficients were associated with partition coefficients as well as solubility parameters and contact angle values. Primary factor determining solubility was affinity between the aroma compounds and the polymeric films. Transport coefficients of eucalyptol in the vapor phase followed the same trends as in the liquid phase with about 3‐fold greater. Understanding interaction phenomenon between the key aroma compound and major packaging films may contribute to improvements in film selection and the design of food packaging applications. Finding from this research contributes toward future development of the high‐aroma barrier materials. Copyright © 2011 John Wiley & Sons, Ltd.
Real wave packet and flux analysis studies of the H + F2 → HF + F reaction
Authors: Gogtas Fahrettin , Karabulut Ezman , Tanaka Tomokazu , Takayanagi Toshiyuki , Tutuk Rukiye
Published: August 2011

The H + F2 → HF + F reaction on ground state potential energy surface is investigated using the quantum mechanical real wave packet and Flux analysis method based on centrifugal sudden approximation. The initial state selected reaction probabilities for total angular momentum J = 0 have been calculated by both methods while the probabilities for J > 0 have been calculated by Flux analysis method. The initial state selected reaction probabilities, integral cross sections and rate coefficients have been calculated for a broad range of collision energy. The results show a large rotational enhancement of the reaction probability. Some resonances were seen in the state‐to‐state reaction probabilities while state‐to‐all reaction probabilities and the reaction cross section do not manifest any oscillations and the initial state selected reaction rate constants are sensitive to the temperature. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Effects of perinatal asphyxia on rat striatal cytoskeleton
Authors: Saraceno G.E. , Ayala M.V. , Badorrey M.S. , Holubiec M. , Romero J.I. , Galeano P. , Barreto G. , Giraldez‐Alvárez L.D. , Kölliker‐fres R. , Coirini H. , Capani F.
Published: August 2011

Perinatal asphyxia (PA) is a medical condition associated with a high short‐term morbimortality and different long‐term neurological diseases. In previous works, we have shown that neuronal and synaptic changes in rat striatum lead to ubi‐protein accumulation in post‐synaptic density (PSD) after six months of sub‐severe PA. However, very little is known about the synaptic and related structural modifications induced by PA in young rats. In the present work, we studied neuronal cytoskeleton modifications in striatum induced by subsevere PA in 30‐day‐old rats. We observed a significant decrease in the number of neurons, in particular calbindin immunoreactive neurons after PA. In addition, it was also observed that actin cytoskeleton was highly modified in the PSD as well as an increment of F‐actin staining by Phalloidin‐alexa488 in the striatum of PA rats. Using correlative fluorescence‐electron microscopy photooxidation, we confirmed and extended confocal observations. F‐actin staining augmentation was mostly related with an increment in the number of mushroom‐shaped spines. Consistent with microscopic data, Western blot analysis revealed a β‐actin increment in PSD in PA rats. On the other hand, MAP‐2 immunostaining was decreased after PA, being NF‐200 expression unmodified. Although neuronal death was observed, signs of generalized neurodegeneration were absent. Taken together these results showed early post‐synaptic F‐actin cytoskeleton changes induced by PA with slightly modifications in the other components of the neuronal cytoskeleton, suggesting that F‐actin accumulation in the dendritic spines could be involved in the neuronal loss induced by PA. Synapse, 2012. © 2011 Wiley Periodicals, Inc.
Evolutionary computation for training set selection
Authors: García‐Pedrajas Nicolás
Published: August 2011

Instance selection is becoming increasingly relevant because of the large amount of data that is constantly being produced in many fields of research. Two basic approaches exist for instance selection: instance selection as a method for prototype selection for instance‐based methods (such as k‐nearest neighbors) and instance selection for obtaining the training set for classifiers that require a learning process (such as decision trees or neural networks). In this paper, we review the methods that have been developed thus far for the latter approach within the field of evolutionary computation. Different groups of learning algorithms require different instance selectors to suit their learning/search biases. This requirement may render many instance selection algorithms useless if their philosophy of design is not suitable for the problem at hand. Evolutionary algorithms do not assume any structure of the data or any behavior of the classifier but instead adapt the instance selection to the performance of the classifier. They are therefore very suitable for training set selection. The main algorithms that have been developed for decision trees, artificial neural networks, and other classifiers are presented. We also discuss the relevant issue of the scalability of these methods to very large datasets. Although current algorithms are useful for fairly large datasets, scaling problems are found when the number of instances is in the hundreds of thousands or millions. © 2011 John Wiley & Sons, Inc. WIREs Data Mining Knowl Discov 2011 1 512–523 DOI: 10.1002/widm.44

This article is categorized under:

Technologies > Computational Intelligence

Technologies > Computer Architectures for Data Mining

Technologies > Data Preprocessing
Monitoring the gestation period of rescued Formosan pangolin (Manis pentadactyla pentadactyla) with progesterone radioimmunoassay
Authors: Chin Shih‐Chien , Lien Chen‐Yen , Chan Ya‐Ting , Chen Chun‐Lin , Yang Yi‐Ching , Yeh Lih‐Seng
Published: August 2011

Eight species of pangolin have been identified in the world. However, understanding of pangolin reproductive biology has been limited to fragmentary records. In this study, the concentration of serum progesterone in three pregnant and two nonpregnant rescued female Formosan pangolins (Manis pentadactyla pentadactyla) was monitored using a commercial progesterone radioimmunoassay kit. During gestation, the serum progesterone of pregnant pangolins A, B, and C remained at 28.5–55 ng/ml (n = 31 samples), 10.9–50.1 ng/ml (n = 34), and 12.4 and 33.5 ng/ml with a peak at 47.6 ng/ml (n = 19), respectively, whereas the serum progesterone of nonpregnant pangolins D and E remained at 1.99 ± 1.62 ng/ml (n = 80) and 2.27 ± 1.64 ng/ml (n = 27), respectively. From this study, it was found that female pangolin weighing as low as 2.14 kg was already capable of reproduction. For pregnant pangolins to give birth to viable offspring, their body weight must increase significantly, 63.89 and 134.0% in the study, from the time of inception or early pregnancy until parturition. In addition, study has found that both viable offspring were born fully developed and exceeded 80 g in weight. The period of gestation was found to be as short as 318 or longer than 372 days. Therefore, the Formosan pangolin should only be able to reproduce once a year. This study is the first insight into hormone assay for determining the gestation period of pangolin. Further investigations on the same subject are necessary to establish criteria for the recognition of reproductive status in pangolins. Zoo Biol 31:479–489, 2012. © 2011 Wiley Periodicals, Inc.
Resting orientation enhances prey survival on strongly structured background
Authors: Wang Zhen , Schaefer H. Martin
Published: August 2011

Prey can use various camouflage types as defense against predators. One of the most common and important types is background matching, which occurs if an animal matches the background in color, brightness, and pattern. Although background matching has been studied intensively, the effects of the resting orientation of prey on the effectiveness of camouflage through background matching are not well known in natural conditions. Several past experimental studies have been conducted on resting orientation in the lab often using the visual system of humans. Their results revealed that the detection rates of predators hinge on the combination of the resting orientation of artificial moths and their background. Here, we studied whether survival rates of artificial moth‐like models depend on their resting orientation in the wild where the visual conditions and detection distances vary. We used a 2 × 2 design of two resting positions of a horizontally and a vertically striped morph on tree bark. Our results show that the survival probability of moths depended mainly on the orientation of stripes relative to the vertical structure of tree bark. Thus, resting orientation relative to background affected survival. After reanalyzing Endler's (Biol J Linn Soc 22:187–231, 1984) data on resting habitats of 317 species of North American moths, we found that horizontally striped moths occurred frequently on small herbs and tree bark. We suggest that it would be beneficial for striped moths to orient non‐randomly on strongly structured background, like furrows of tree bark. We further suggest that background matching was more important than coincident disruptive coloration in determining the survival rates of our artificial moths.
Ejaculatory dysfunction as a cause of infertility
Authors: Kondoh Nobuyuki
Published: August 2011

Ejaculatory dysfunction (EjD), the most prevalent male sexual disorder, is clearly different from erectile dysfunction (ED). EjD is divided into 4 categories: premature ejaculation, delayed ejaculation, retrograde ejaculation and anejaculation. EjD‐related infertility is one of the most serious problems in young patients. If sexual intercourse is achieved successfully without any ejaculate sexual partners/wives will not be able to conceive. Therefore, establishment of management of EjD as well as ED is increasingly crucial for couples wishing for a baby. The therapeutic approach of EjD‐related infertility is based upon two scenarios: (1) if EjD alone is the reason for having no children, adequate treatment for EjD alone is required, or (2) if EjD is not the only reason and is combined with a worsening of semen quality, total management for male infertility (including EjD treatment) is needed. In this article, the background of EjD‐related infertility is presented briefly, followed by a review of treatment modalities.
Kinetic Chains: A Review of the Concept and Its Clinical Applications
Authors: Karandikar Ninad , Vargas Oscar O. Ortiz
Published: August 2011

During the past decade, our understanding of biomechanics and its importance in rehabilitation has advanced significantly. The kinetic chain, a concept borrowed from engineering, has helped us better understand the underlying physiology of human movement. This understanding, in turn, has facilitated the development of new and more rational rehabilitation strategies. The kinetic chain concept has application in a wide spectrum of clinical conditions, including musculoskeletal medicine, sports medicine, and neurorehabilitation, as well as prosthetics and orthotics. The purpose of this review is to provide insights into the biomechanics related to the concept of kinetic chains, with a specific focus on closed kinetic chains and its clinical applications in rehabilitation.