bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogeography of North American herbaceous Smilax (Smilacaceae): Combined AFLP and cpDNA data support a northern refugium in the Driftless Area
Authors: Li Pan , Li Mimi , Shi Yin , Zhao Yunpeng , Wan Ying , Fu Chengxin , Cameron Kenneth M.
Published: March 2013

• Premise of the study: The genetic structure of North American herbaceous Smilax, a clade of closely related understory herbs that has a wide and disjunct distribution, was investigated to test the hypothesis of whether a northern refugium in the upper Midwest may have existed for these plants during the last glaciation.

• Methods: We analyzed 33 populations sampled from California and throughout the eastern United States using AFLP and chloroplast DNA sequence data.

• Key results: Individuals of S. jamesii from northern California formed a clade sister to the eastern North American species, and they likely diverged from each other during the Pleistocene. Among the eastern species, two lineages were found on opposite sides of the Appalachian Mountains. The populations near the “Driftless Area” contained most of the chlorotypes found in the Midwest, including a unique one endemic to this area, and the AFLP data indicated that one population from this area has the highest frequency‐down‐weighted‐marker value.

• Conclusions: This study, and others that have focused on mammals, amphibians, and woody plants, provides further evidence for the debate over whether the upper Midwest's “Driftless Area” may have hosted a biologically diverse northern glacial refugium. Herbaceous species of Smilax from eastern North American exhibit an Appalachian discontinuity. They appear to have persisted in multiple refugia both east and west of the Appalachians, with several populations persisting in situ through the Last Glacial Maximum (LGM). We suggest that they experienced localized expansion after the LGM, possibly followed by subsequent contact between the Midwest and the East Coastal lineages.
Hormonal interactions and gene regulation can link monoecy and environmental plasticity to the evolution of dioecy in plants
Authors: Golenberg Edward M. , West Nicholas W.
Published: March 2013

Most models for dioecy in flowering plants assume that dioecy arises directly from hermaphroditism through a series of independent feminizing and masculinizing mutations that become chromosomally linked. However, dioecy appears to evolve most frequently through monoecious grades. The major genetic models do not explain the evolution of unisexual flowers in monoecious and submonoecious populations, nor do they account for environmentally induced sexual plasticity. In this review, we explore the roles of environmental stress and hormones on sex determination, and propose a model that can explain the evolution of dioecy through monoecy, and the mechanisms of environmental sex determination.

Environmental stresses elicit hormones that allow plants to mediate the negative effects of the stresses. Many of these same hormones are involved in the regulation of floral developmental genes. Recent studies have elucidated the mechanisms whereby these hormones interact and can act as switchpoints in regulatory pathways. Consequently, differential concentrations of plant hormones can regulate whole developmental pathways, providing a mechanism for differential development within isogenic individuals such as seen in monoecious plants. Sex‐determining genes in such systems will evolve to generate clusters of coexpressed suites. Coexpression rather than coinheritance of gender‐specific genes will define the sexual developmental fate. Therefore, selection for gender type will drive evolution of the regulatory sequences of such genes rather than their synteny. Subsequent mutations to hyper‐ or hyposensitive alleles within the hormone response pathway can result in segregating dioecious populations. Simultaneously, such developmental systems will remain sensitive to external stimuli that modify hormone responses.
Polymorphic microsatellite loci for Virola sebifera (Myristicaceae) derived from shotgun 454 pyrosequencing
Authors: Wei Na , Dick Christopher W. , Lowe Andrew J. , Gardner Michael G.
Published: March 2013

• Premise of the study: Polymorphic microsatellite loci were characterized in the dioecious neotropical rainforest tree Virola sebifera. The markers will be used to study ecological and genetic impacts of hunting and landscape change in this vertebrate‐dispersed, insect‐pollinated tree species.

• Methods and Results: Simple sequence repeat (SSR) markers were screened from genomic libraries of South American V. sebifera obtained by shotgun 454 pyrosequencing. Primer pairs were tested on Panamanian samples (N = 42). Approximately 52% of the 61 tested SSR markers amplified, and 16% were polymorphic. Ten selected polymorphic SSR loci contained seven to 15 alleles per locus, and polymorphic information content averaged 0.694. Observed heterozygosity ranged from 0.465 to 0.905, and expected heterozygosity was between 0.477 and 0.876.

• Conclusions: The 10 polymorphic loci will be useful in studying gene flow and genetic structure at local and regional spatial scales in V. sebifera.
Phosphorus Partitioning of Soybean Lines Containing Different Mutant Alleles of Two Soybean Seed‐Specific Adenosine Triphosphate‐Binding Cassette Phytic Acid Transporter Paralogs
Authors: Gillman Jason D. , Baxter Ivan , Bilyeu Kristin
Published: March 2013

Seed phytate is a repository of P and minerals in soybean [Glycine max (L.) Merr.] seeds that limits P and mineral bioavailability for monogastric animals (e.g., humans, swine [Sus scrofa], and poultry [especially chicken, Gallus domesticus]) due to insufficient digestive tract phytase activity. We previously identified epistatic recessive mutations affecting two paralogous adenosine triphosphate‐binding cassette phytic acid transporter genes (one a nonsense mutation in Lpa1 and the other a missense mutation in Lpa2) as the molecular genetic basis in the ethyl methanesulfonate (EMS)‐induced mutant low phytate soybean line M153. An additional mutant low phytate line, M766, contained one single nucleotide polymorphism within the ninth intron of the Lpa1 locus as well as a nonsense mutation in Lpa2. The objectives of this research were to clarify the genetics underlying the low phytate phenotype in line M766 and to determine P partitioning in new combinations of mutant alleles from M766 and M153. Inheritance of nonsense alleles affecting both low phytic acid (Lpa) genes (one from M153 and one from M766) led to the production of viable seeds that contained transgressive reductions in total seed phytate and significantly higher levels of inorganic phosphate than has been reported for nontransgenic soybean material and will allow efficient molecular selection of soybeans with even greater reductions of phytate for improved quality soybean meal.
Genomic Selection Accuracy using Historical Data Generated in a Wheat Breeding Program
Authors: Storlie Eric , Charmet Gilles
Published: March 2013

Cross‐validation (CRV) methods were designed to simulate genomic selection (GS) for yield in a wheat (Triticum aestivum L.) breeding program with data of 318 genotypes grown over an 11‐yr period at six locations in France. Two methods, CVSWO (cross‐validation‐specific without location as factor) and CVSW (cross‐validation‐specific with location as factor), included 11 folds, each comprising genotypes grown during a specific year and each representing target populations, while the remaining folds comprising genotypes grown during the other 10 yr represented training populations. These methods were compared with CVRWO (cross‐validation‐random without location as factor) and CVRW (cross‐validation‐random with location as factor), designed to simulate standard CRV while retaining the structure of the first two CRV methods; the same 318 genotypes were used to create 11 folds, each comprising randomly selected genotypes. Results suggest the accuracy of the CRV methods using specifically selected genotypes (correlation coefficient between (marker based) estimate of breeding value and observed phenotype [rM] = 0.20) based on years grown were significantly less than methods using randomly selected genotypes (rM = 0.40–0.50). These results imply wheat yield is more difficult to predict for unknown, futuristic years than standard CRV methods suggest. An alternative measure of accuracy based on predicted genotypic ranks, termed predicted rank conversion (PRC), was implemented for the purpose of improving accuracies and reducing the differences between CRV methods.
Des « long timers » au sommet de l'État Américain
Authors: Darviche Mohammad-Saïd , Genieys William , Hoeffler Catherine , Joana Jean
Published: March 2013

La forte circulation des élites politiques et administratives américaines entre la société civile et les positions de pouvoir est au fondement de la thèse d’un État faible américain. La pratique du revolving door , se traduisant par une grande mobilité professionnelle et des allers retours nombreux entre secteurs public et privé, conforte en effet l’image d’un État fortement fragmenté et largement ouvert aux pressions exogènes des différents groupes sociaux. L’examen du groupe formé par les long timers des secteurs de la défense et de la santé, c’est-à-dire des political appointees et des staffers qui occupent durablement les positions institutionnelles les plus élevées au sein de l’Exécutif ou du Congrès, permet de tracer un tableau différent. Il met en évidence des carrières et des parcours professionnels se caractérisant par un enracinement sectoriel important, antérieur à l’entrée en position, et centré sur les différentes institutions de pouvoir washingtoniennes entre lesquelles circulent une partie de ces acteurs. Sans permettre de préjuger de l’influence qui en résulte pour ces élites, ces caractéristiques témoignent des ressources sociales et politiques qui prédisposent les membres de ce groupe à la mise en forme des politiques publiques.
Renal Cell Carcinoma in a Horseshoe Kidney: Radiology and Pathology Correlation
Authors: Alamer Ali
Published: March 2013

Renal cell carcinoma (RCC) is encountered in about 3% of all adult neoplasms. Presence of any kidney malformation can change the plan for surgical treatment of RCC with organ preserving surgery. We report a case of clear cell RCC in a horseshoe kidney. Computed tomography scan revealed a horseshoe kidney anomaly with a large mass in the left side. The diagnosis of RCC was confirmed by pathology and histology findings.
Lifestyle intervention as a treatment for obesity in school-age-children in Celaya, Guanajuato: An experimental study
Authors: Padilla-Raygoza Nicolas , Diaz-Guerrero Rosalina , Ruiz-Paloalto Ma. Laura
Published: March 2013

Introduction: Obesity is a risk factor in chronic diseases, and its frequency among children in Mexico is increasing. Objective: To determine the effect of lifestyle intervention as a treatment for obesity in school-age-children from Celaya, Mexico.Methodology: For this experimental study, four schools were randomly selected. Children and parents participated voluntarily and signed consent forms. Two schools were chosen as the experimental group and the other two formed the control group. Age, gender, weight, height, BMI and blood pressure were recorded for each participant. Intervention: Children and parents were asked to walk in their schools for 30 minutes a day Monday through Friday and to attend 8 instructional sessions over a period of four months dedicated to the selection and preparation of meals. Statistical Analysis: The OR and 95% CI were calculated to determine the effect of the intervention; a Z-test for two proportions for overweight and obesity in the control and experimental groups were carried out for comparison.Results: 157 children were included in the experimental group and 144 in the control group. To compare the proportions of the overweight and the obese between the groups, a Z-test = - 0.36 (p-value 0.72) were obtained showing no effect of the intervention in lifestyle; OR =1.09, 95% CI (0.67, 1.77). It was adjusted according to the attendance to the sessions resulting in an OR = 2.00, 95% CI (0.69, 5.77), demonstrating that not attending the sessions was a confounder.Conclusions: Intervention in lifestyle should be measured over a longer period of time in order to determine what effects it may have on changes in body mass index.
Effect of Butyrylated Arrowroot Starch to the Digesta Profile and Molar Ratio SCFA
Authors: Damat Damat
Published: March 2013

The research was conducted to determine the effects of Butyrylated Arrowroot Starch (BAS) to the digesta profile and Short Chain Fatty Acids (SCFA) molar ratio. The research was conducted by using simple complete randomized design (CRD). The treatment tested was feed type, which consists of 5 levels, namely natural arrowroot starch, BAS with Degree of Substitution (DS) 0.053; 0.120; 0.187 and AIN93 natural feed. The study was conducted by using 30 Sprague Dawley rats, which were divided into 5 groups, each group consisting of 6 tails. Feeding treatments were given from dayseven until day 33. On day-34 analysis was conductedof the digesta profile and the SCFA molar ratio. Based on the analysis results, it is known that BAS feeding increased digesta weight, decreased digesta pH and increased digesta water content when compared with the AIN93 standard feed. Largest amount of digesta, lowest digesta pH, and highest water content of digesta, respectively 7.19 g, 6.53 and 91.23%, wasobtained from rats fed BAS with DS 0.187. The molar ratio of butyric acid in digesta also increased along with the increasing BAS DS.
A subclass of close-to-convex functions
Authors: Zhang Zheng- Lv , Xu Qing- Hua
Published: March 2013

In this paper, we introduce and investigate an interesting subclass $\mathcal {J}_\alpha(h)$ of analytic and close-to-convex function in the open unit disk D. several coefficient inequalities, growth, and distortion theorem for this class are proved. The various results presented here would generalize many know results.
Certain new classes of meromorphic functions related with a convolution operator
Authors: Hussain Saqib , Butt Adil Wahid , Zahid Muhammad
Published: March 2013

Recently, Hussain [Hussain, Saqib (2010). Some applications of Miller-Mocanu lemma on certain classes of meromorphic functions, \textquotedblright Appl. Math. Comput.\textquotedblright , 216(2010), 3016-3021], introduced certain new classes of meromorphic functions using newly defined convolution operators. The purpose of present investigation is to extend the work of Hussain by considering some new classes of meromorphic functions. We derive some inclusion relationships, coefficient bound, integral representation and extreme point theorem.
The Use of an In-Situ Measurement to Probe the Solidification Kinetics of Injection-Molded HDPE/PP Blends
Authors: Yang Bin , Li Gui-Jing , Yang Ming-Bo , Su Li-Feng , Miao Ji-Bin , Xia Ru , Chen Peng , Deng Shuang-Quan , Qian Jia-Sheng
Published: March 2013

The largest portion of an injection molding (IM) cycle is actually occupied by the melt cooling stage, which also significantly dictates many end-use properties of the final parts, especially for crystalline polymers which undergo both solidification and crystallization processes simultaneously. The solidification kinetics of HDPE/PP blends were investigated under injection molding conditions with the aid of an in-situ measurement of in-cavity temperature profiles throughout the IM process. The obtained experimental results were in good agreement with our previous theoretical predictions. The present study will be instructive to the optimization of processing variables, and supplies good insight into the formation of various crystalline structures in injection-molded articles.
Kinetic Studies on Cure Kinetics of DGEBA (Diglycidyl Ether of Bisphenol-A) with Terephthalamide Hardening System generated from PET waste
Authors: Dutt Krishna , Soni R.K. , Teotia Meenu , Sharma S.P. , Singh Harjeet
Published: March 2013

An aromatic amide system for epoxy resin based on diglycidyl ether of Bisphenol-A was developed through ammonolysis of PET waste. The ammonolysis of PET waste was carried out at ambient conditions of temperature & pressure. The end product, characterized as terephthalamide was used as hardener in epoxy resin (Diglycidal ether of Bisphenol-A) and triethylamine and sodium hydroxide were used as catalysts. Several samples were used to study the curing kinetics having varying amounts of the catalysts by means of Differential scanning calorimetry (DSC). Isothermal and Dynamic DSC characterization of the formulations were performed. The curing kinetics of terephthalamide with epoxy resin shows high energy of activation as 50.18 KJ/mole in the absence of catalyst which was lowered towards negative values in their presence. The optimum curing of epoxy resin heated with aromatic hardener can be obtained in 28 minutes at 320 ˚C. The use of catalysts reduced the curing time to 2.0 minutes at 60 ˚C.
Intensification of Conductivity and Solubility of Polypyrrole Using Acrylic Acid and Polyacrylic Acid Dopants
Authors: Meenakshi P. , Selvaraj M. , Ramu S.
Published: March 2013

Doped polypyrrole (PPy) was synthesized using FeCl3 as an oxidant, acrylic acid and poly(acrylic acid) as dopants. The effects of dopants and doping level on the solubility and conductivity parameters were optimized. The doped PPy was characterized using FT-IR, UV-Vis and EPR measurements. The thermal stability of doped PPy was studied by TGA/DSC analysis. The morphology of the doped PPy was studied using Scanning Electron Microscope. The Electrochemical study of the doped PPy was carried out by Electrochemical Impedance Spectroscopy (EIS). This study reveals that the polyacrylic acid doped PPy shows higher conductivity than its monomer acrylic acid and the water soluble nature was also augmented at higher doping level of polyacrylic acid on the PPy.
Acute Hematologic and Mucosal Toxicities in Head and Neck Cancer Patients Undergoing Chemoradiotherapy: A Comparison of 3D-CRT, IMRT, and Helical Tomotherapy
Authors: Kruser Tim J. , Rice Stephanie R. , Cleary Kevin P. , Geye Heather M. , Tome Wolfgang A. , Harari Paul M. , Kozak Kevin R.
Published: March 2013

IMRT and helical tomotherapy for head and neck cancer (HNC) treatment are associated with higher doses to certain non-target tissues than traditional static beam techniques. We hypothesized that this may lead to higher acute mucosal and hematologic toxicities. This analysis was limited to 178 patients receiving >60 Gy with concurrent weekly cisplatin. Radiation delivery used 3D-CRT in 41 patients (23%), conventional IMRT in 56 patients (31%), and helical tomotherapy in 81 patients (46%). Acute mucositis rates, weekly hematologic parameters, and ability to deliver planned chemotherapy cycles were examined for each patient during their course of chemoradiotherapy. Analysis showed patients were well balanced with regard to sex, age, and stage. Treatment time, as assessed by delivered monitor units, varied significantly between the 3D-CRT (median = 502), IMRT (median = 1087), and tomotherapy (median = 6757) cohorts. Acute mucositis grades did not significantly differ between the three subsets. Through six weeks of chemoradiotherapy, the median decline in hemoglobin was 15.6%, the median decline in platelets was 30.6%, and the median decline in leukocytes was 51.5%, but these drops were not significantly different between treatment cohorts. Chemotherapy was discontinued or held secondary to hematologic toxicity in 12% of 3D-CRT patients, 5% of IMRT patients and 15% of tomotherapy patients ( p = 0.14). In conclusion, HNC patients undergoing high dose radiation with concurrent weekly cisplatin chemotherapy, the longer beam-on times and larger volumes of low-to-moderate radiation doses to non-target tissues associated with modern IMRT delivery techniques do not appear to result in increased acute hematologic or mucosal toxicities.
An anthropological genetic perspective on creolization in the anglophone caribbean
Authors: Torres Jada Benn , Stone Anne C. , Kittles Rick
Published: March 2013

Variable socio‐cultural influences developed in the colonial Caribbean as a result of competing European hegemonic rule. In this study, we examine how colonial regulations regarding social hierarchies and mate choice worked to influence the genetic landscape of contemporary African Caribbean populations. To this end, 420 individuals from Dominica, Grenada, St. Kitts, St. Lucia, St. Thomas, St. Vincent, Jamaica, and Trinidad were genotyped for 105 autosomal ancestry informative markers. Based on these data, population substructure and admixture were assessed using an exact test, a model‐based clustering method, and principal components analysis. On average, individual admixture estimates of the pooled African Caribbean sample were 77% (SD ± 18%) West African, 15% (SD ± 15%) European, and 7.7% (SD ± 8%) Native American. In general, ancestry estimates were significantly different between Dominica and all other islands. Genetic structure analyses indicated subdivision into two subpopulations on most islands. Finally, unlike all of the other Caribbean populations that clustered adjacent to African populations, the Dominican population was more intermediate between the three parental groups in the principal components plot. As a result of the significant French influence throughout Dominican history, Dominica did not have the same cultural influences that typified other Anglophone colonies. Consequently, there were different social hierarchies and resulting mate choices on Dominica compared with the other considered islands. This study highlights the complex socio‐cultural history of a broad region of the Caribbean and attests to the interplay between social and biological factors in shaping the genetic diversity present in present‐day communities. Am J Phys Anthropol 151:135–143, 2013. © 2013 Wiley Periodicals, Inc.
Inhibition of microsomal cortisol production by (–)‐epigallocatechin‐3‐gallate through a redox shift in the endoplasmic reticulum—A potential new target for treating obesity‐related diseases
Authors: Szelényi Péter , Révész Katalin , Konta Laura , Tüttõ Anna , Mandl József , Kereszturi Éva , Csala Miklós
Published: March 2013

Conversion of cortisone to cortisol by 11β‐hydroxysteroid dehydrogenase type 1 (11βHSD1) in the endoplasmic reticulum (ER) of the target cells is a major determinant of glucocorticoid action, and plays an important role in the development of obesity‐related diseases. Inhibition of 11βHSD1 activity is, therefore, considered as a promising novel strategy for the treatment of metabolic syndrome and diabetes. Tea flavanols and their major representative, epigallocatechin gallate are known as antiobesity and antidiabetic agents. Their impacts on blood glucose level, hepatic glucose production, and insulin responsiveness resemble those observed on inhibition or depletion of 11βHSD1. We aimed to study the effect of epigallocatechin gallate on 11βHSD1 activity in ER‐derived rat liver microsomes by measuring cortisone and cortisol with HPLC. Cortisol production was efficiently suppressed in a concentration dependent manner in intact microsomal vesicles. However, this effect was abolished by membrane permeabilization; and the three proteins involved in the overall process (11βHSD1, hexose 6‐phosphate dehydrogenase, and glucose 6‐phosphate transporter) were not or only mildly affected. Further investigation revealed the oxidation of luminal NADPH to NADP+, which attenuates cortisone reduction and favors cortisol oxidation in this compartment. Such a redox shift in the ER lumen might contribute to the beneficial health effects of tea flavanols and should be regarded as a promising strategy for the development of novel selective 11βHSD1 inhibitors to treat obesity‐related diseases. © 2013 BioFactors 39(5):534–541, 2013
Supplementation with apple enriched with L‐arginine may improve metabolic control and survival rate in alloxan‐induced diabetic rats
Authors: Escudero Andrea , Petzold Guillermo , Moreno Jorge , Gonzalez Marcelo , Junod Julio , Aguayo Claudio , Acurio Jesenia , Escudero Carlos
Published: March 2013

Supplementation with L‐arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L‐arginine offer additional benefits compared to L‐arginine by itself in a preclinical study of diabetes. This study combines food‐engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non‐diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan‐induced diabetic animals exhibited a reduction (∼50%) in the L‐arginine uptake. This effect was reverted by L‐arginine pretreatment (12 H) in both the normal and diabetes‐derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L‐arginine (375 mg/kg per 10 days) or apple enriched with L‐arginine or vehicle (control). In a preliminary analysis, supplementation with L‐arginine by itself (50%) or apple enriched with L‐arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L‐arginine, as well as plasma concentration of nitrites and insulin in the L‐arginine or apple + L‐arginine groups after supplementation. Apple + L‐arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L‐arginine offers more benefits than L‐arginine by itself in this preclinical study. © 2013 BioFactors 39(5):564–574, 2013
The stress response resolution assay. II. Quantitative assessment of environmental agent/condition effects on cellular stress resolution outcomes in epithelium
Authors: Walker Dale M. , Nicklas Janice A. , Walker Vernon E.
Published: March 2013

Cellular stress responses consist of a complex network of pathways and linked processes that, when perturbed, are postulated to have roles in the pathogenesis of various human diseases. To assess the impact of environmental insults upon this network, we developed a novel stress response resolution (SRR) assay for investigation of cellular stress resolution outcomes and the effects of environmental agents and conditions thereupon. SRR assay‐based criteria identified three distinct groups of surviving cell clones, including those resembling parental cells, those showing Hprt/HPRT mutations, and a third type, “Phenotype‐altered” clones, that occurred predominantly in cells pretreated with a chemical mutagen, was heterogeneous in nature, and expressed significant alterations in cell morphology and/or function compared with parental cells. Further evaluation of Phenotype‐altered clones found evidence of various alterations that resembled epithelial‐to‐mesenchymal transition, phenotype switching, checkpoint dysfunction, senescence barrier bypass, and/or epigenetic reprogramming. Phenotype‐altered clones were found to occur spontaneously in a cell line with a mutator phenotype, to represent the major surviving clone type in a variation of the SRR assay, and to be tumorigenic in nude mice. Assessment of SRR assay final results showed that pretreatment with a chemical mutagen induced significant changes in cellular stress response prosurvival capacity, in damage avoidance versus damage tolerance stress resolution outcomes, and in the damage burden in the final surviving cell populations. Taken together, these results support the conclusion that use of the SRR assay can provide novel insights into the role of environmental insults in the pathogenesis of cancer and other human diseases. Environ. Mol. Mutagen. 54:281–293, 2013. © 2013 Wiley Periodicals, Inc.
The stress response resolution assay. I. Quantitative assessment of environmental agent/condition effects on cellular stress resolution outcomes in epithelium
Authors: Walker Dale M. , Patrick O'Neill J. , Tyson Frederick L. , Walker Vernon E.
Published: March 2013

The events or factors that lead from normal cell function to conditions and diseases such as aging or cancer reflect complex interactions between cells and their environment. Cellular stress responses, a group of processes involved in homeostasis and adaptation to environmental change, contribute to cell survival under stress and can be resolved with damage avoidance or damage tolerance outcomes. To investigate the impact of environmental agents/conditions upon cellular stress response outcomes in epithelium, a novel quantitative assay, the “stress response resolution” (SRR) assay, was developed. The SRR assay consists of pretreatment with a test agent or vehicle followed later by a calibrated stress conditions exposure step (here, using 6‐thioguanine). Pilot studies conducted with a spontaneously‐immortalized murine mammary epithelial cell line pretreated with vehicle or 20 µg N‐ethyl‐N‐nitrososurea/ml medium for 1 hr, or two hTERT‐immortalized human bronchial epithelial cell lines pretreated with vehicle or 100 µM zidovudine/lamivudine for 12 days, found minimal alterations in cell morphology, survival, or cell function through 2 weeks post‐exposure. However, when these pretreatments were followed 2 weeks later by exposure to calibrated stress conditions of limited duration (for 4 days), significant alterations in stress resolution were observed in pretreated cells compared with vehicle‐treated control cells, with decreased damage avoidance survival outcomes in all cell lines and increased damage tolerance outcomes in two of three cell lines. These pilot study results suggest that sub‐cytotoxic pretreatments with chemical mutagens have long‐term adverse impact upon the ability of cells to resolve subsequent exposure to environmental stressors. Environ. Mol. Mutagen. 54:268–280, 2013. © 2013 Wiley Periodicals, Inc.
Method to help ensure survival of a very small skin paddle of pectoralis major musculocutaneous flap in head and neck reconstruction
Authors: Kim Eun Key , Yang Sung Jun , Choi Seung Ho
Published: March 2013

Background

When the required dimension of skin paddle of a pectoralis major musculocutaneous (PMMC) flap is very small, its survival often becomes questionable. We introduce a simple technique which enlarges the practical dimension of a very small skin paddle, leading to ensure the survival of a PMMC flap.

Method and Result

A PMMC flap size of 1.5 × 4 cm was required for repair of leakage which developed 2 weeks after the primary ablative surgery for hypopharyngeal cancer. The skin paddle was designed in the size of 4.5 × 7 cm and was deepithelized except the original dimension. After the skin edge was sutured to the defect margin, the deepithelized dermal portion covered the repair site to enhance the suture.

Conclusion

The effective dimension of a very small skin paddle can be quite enlarged thus increasing the possibility of capturing perforators. This could decrease the risk of avulsion during flap transfer and provide backing of the repair site. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Influence of cell culture medium composition on in vitro dissolution behavior of a fluoride‐containing bioactive glass
Authors: Shah Furqan A. , Brauer Delia S. , Wilson Rory M. , Hill Robert G. , Hing Karin A.
Published: March 2013

Bioactive glasses are used clinically for bone regeneration, and their bioactivity and cell compatibility are often characterized in vitro, using physiologically relevant test solutions. The aim of this study was to show the influence of varying medium characteristics (pH, composition, presence of proteins) on glass dissolution and apatite formation. The dissolution behavior of a fluoride‐containing bioactive glass (BG) was investigated over a period of one week in Eagle's Minimal Essential Medium with Earle's Salts (MEM), supplemented with either, (a) acetate buffer, (b) 4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) buffer, (c) HEPES + carbonate, or (d) HEPES + carbonate + fetal bovine serum. Results show pronounced differences in pH, ion release, and apatite formation over 1 week: Despite its acidic pH (pH 5.8 after BG immersion, as compared to pH 7.4–8.3 for HEPES‐containing media), apatite formation was fastest in acetate buffered (HEPES‐free) MEM. Presence of carbonate resulted in formation of calcite (calcium carbonate). Presence of serum proteins, on the other hand, delayed apatite formation significantly. These results confirm that the composition and properties of a tissue culture medium are important factors during in vitro experiments and need to be taken into consideration when interpreting results from dissolution or cell culture studies. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 647–654, 2014.
An injectable and biodegradable hydrogel based on poly(α,β‐aspartic acid) derivatives for localized drug delivery
Authors: Lu Caicai , Wang Xiaojuan , Wu Guolin , Wang Jingjing , Wang Yinong , Gao Hui , Ma Jianbiao
Published: March 2013

An injectable hydrogel via hydrazone cross‐linking was prepared under mild conditions without addition of cross‐linker or catalyst. Hydrazine and aldehyde modified poly(aspartic acid)s were used as two gel precursors. Both of them are water‐soluble and biodegradable polymers with a protein‐like structure, and obtained by aminolysis reaction of polysuccinimide. The latter can be prepared by thermal polycondensation of aspartic acid. Hydrogels were prepared in PBS solution and characterized by different methods including gel content and swelling, Fourier transformed‐infrared spectroscopy, and in vitro degradation experiment. A scanning electron microscope viewed the interior morphology of the obtained hydrogels, which showed porous three‐dimensional structures. Different porous sizes were present, which could be well controlled by the degree of aldehyde substitution in precursor poly(aspartic acid) derivatives. The doxorubicin‐loaded hydrogels were prepared and showed a pH‐sensitive release profile. The release rate can be accelerated by decreasing the environmental pH from a physiological to a weak acidic condition. Moreover, the cell adhesion and growth behaviors on the hydrogel were studied and the polymeric hydrogel showed good biocompatibility. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 628–638, 2014.
Bioactive substrates for human retinal pigment epithelial cell growth from elastin‐like recombinamers
Authors: Singh Amar K. , Srivastava Girish K. , Martín Laura , Alonso Matilde , Pastor J. Carlos
Published: March 2013

The aim of this study was to investigate the use of bioactive RGD‐containing elastin‐like recombinamers (ELR‐RGDs) as a substrate that can maintain human retinal pigment epithelial cell (hRPE) phenotype and growth pattern. Results obtained are compared with previously published behavior of ARPE19 cells. The extension of these results to hRPE is required because ARPE19 cells cannot be used clinically to treat age‐related macular degeneration. hRPE cells were isolated, cultured, seeded, and grown on surface of glass, treated polystyrene (TCP), and solvent‐cast ELR‐RGD and ELR‐IK film with no specific sequence. Cells were analyzed to study cell adhesion, proliferation, morphology, and RPE65 protein expression by staining with diamidino‐2‐phenylindole, Rhodamine‐Phalloidin, and anti‐RPE65 antibody at 12, 24, 72, 120, 168, and 360 h. hRPE cells always grew better on ELR‐RGD than on glass and ELR‐IK but not on TCP. The kinetic hRPE growth curves confirmed that growth differences started to appear at 24 h for these surfaces in ascending order of cell growths, namely glass, ELR‐IK, ELR‐RGD, and TCP. There was a clear difference at 360 h. ELR‐RGD maintained hRPE cells stable morphology and RPE65 protein expression. ELR‐RGD seems to be a good substrate for growing hRPE cells with stable morphology and RPE65 protein expression. As such, this work confirms our hypothesis regarding ELR‐RGD substrates viability, which can be used as a Bruch's membrane prosthesis for further studies in animals. However, these results must subsequently be extrapolated to use of hRPE cells in animals to evaluate them as a transplantation vehicle in human. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 639–646, 2014.
Development of a guided bone regeneration device using salicylic acid‐poly(anhydride‐ester) polymers and osteoconductive scaffolds
Authors: Mitchell Ashley , Kim Brian , Cottrell Jessica , Snyder Sabrina , Witek Lukasz , Ricci John , Uhrich Kathryn E. , Patrick O'Connor J.
Published: March 2013

Successful repair of craniofacial and periodontal tissue defects ideally involves a combined therapy that includes inflammation modulation, control of soft tissue infiltration, and bone regeneration. In this study, an anti‐inflammatory polymer, salicylic acid‐based poly(anhydride‐ester) (SAPAE) and a three‐dimensional osteoconductive ceramic scaffold were evaluated as a combined guided bone regeneration (GBR) system for concurrent control of inflammation, soft tissue ingrowth, and bone repair in a rabbit cranial defect model. At time periods of 1, 3, and 8 weeks, five groups were compared: (1) scaffolds with a solid ceramic cap (as a GBR structure); (2) scaffolds with no cap; (3) scaffolds with a poly(lactide‐glycolide) cap; (4) scaffolds with a slow release SAPAE polymer cap; and (5) scaffolds with a fast release SAPAE polymer cap. Cellular infiltration and bone formation in these scaffolds were evaluated to assess inflammation and bone repair capacity of the test groups. The SAPAE polymers suppressed inflammation and displayed no deleterious effect on bone formation. Additional work is warranted to optimize the anti‐inflammatory action of the SAPAE, GBR suppression of soft tissue infiltration, and stimulation of bone formation in the scaffolds and create a composite device for successful repair of craniofacial and periodontal tissue defects. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 655–664, 2014.
Evaluation of magnesium‐yttrium alloy as an extraluminal tracheal stent
Authors: Luffy Sarah A. , Chou Da‐Tren , Waterman Jenora , Wearden Peter D. , Kumta Prashant N. , Gilbert Thomas W.
Published: March 2013

Tracheomalacia is a relatively rare problem, but can be challenging to treat, particularly in pediatric patients. Due to the presence of mechanically deficient cartilage, the trachea is unable to resist collapse under physiologic pressures of respiration, which can lead to acute death if left untreated. However, if treated, the outcome for patients with congenital tracheomalacia is quite good because the cartilage tends to spontaneously mature over a period of 12 to 18 months. The present study investigated the potential for the use of degradable magnesium‐3% yttrium alloy (W3) to serve as an extraluminal tracheal stent in a canine model. The host response to the scaffold included the formation of a thin, vascularized capsule consisting of collagenous tissue and primarily mononuclear cells. The adjacent cartilage structure was not adversely affected as observed by bronchoscopic, gross, histologic, and mechanical analysis. The W3 stents showed reproducible spatial and temporal fracture patterns, but otherwise tended to corrode quite slowly, with a mix of Ca and P rich corrosion product formed on the surface and observed focal regions of pitting. The study showed that the approach to use degradable magnesium alloys as an extraluminal tracheal stent is promising, although further development of the alloys is required to improve the resistance to stress corrosion cracking and improve the ductility. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 611–620, 2014.
Obesity and melanoma: Exploring molecular links
Authors: Chen Jiezhong , Chi Mengna , Chen Chen , Zhang Xu Dong
Published: March 2013

Obesity is now a major health problem due to its rapidly increasing incidence worldwide and severe consequences. Among many conditions associated with obesity are some cancers including melanoma. Both genetic defects and environmental risk factors are involved in the carcinogenesis of melanoma. Activation of multiple signal pathways such as the PI3K/Akt and MAPK pathways are necessary for the initiation of melanoma. Activation of the MAPK pathway as a result of activating mutations in BRAF is commonly seen in melanoma though it alone is not sufficient to cause malignant transformation of melanocytes. Obesity can result in the activation of many signal pathways including PI3K/Akt, MAPK, and STAT3. The activation of these pathways may have a synergistic effect with the genetic defects thereby increasing the incidence of melanoma. J. Cell. Biochem. 114: 1955–1961, 2013. © 2013 Wiley Periodicals, Inc.
Protective induction of Hsp70 in heat‐stressed primary myoblasts: Involvement of MAPKs
Authors: Bironaite Daiva , Brunk Ulf , Venalis Algirdas
Published: March 2013

The involvement of extracellular signal‐regulated kinases 1 and 2 (ERK1,2), stress kinase p38 and c‐Jun NH2‐terminal kinases 1 and 2 (JNK1,2) on Hsp70‐upregulation following mild heat shock, and resulting cell protection, was studied on rabbit primary myoblasts. Cells subjected to heat stress (42°C; 60 min) showed a significantly enhanced amount of heat‐shock‐induced protein 70 (Hsp70), correlating with sustained phosphorylation of MAP kinases ERK1,2, inhibition of p38 and JNK1,2 activation. Induced Hsp70 did not autocrinally suppress activation of transcription factor c‐Jun, suggesting involvement of the latter in the protection of myoblasts following heat shock. The inhibition of stress kinases p38, JNK1,2, and MEK1,2 by SP600125, SB203580, and UO126, respectively, established the involvement of JNK1,2 and p38 as upstream, and ERK1,2 as downstream targets of Hsp70 induction. Moreover, the effect of the MEK1,2 inhibitor UO126 revealed a new pathway of c‐Jun activation by ERK1,2 in myogenic heat‐stressed stem cells. The presented data show that transient activation of JNK1, JNK2, and p38 is necessary for Hsp70 induction and ensuing cell protection. In conclusion, affecting myogenic stem cell protective mechanisms might be a useful strategy in improving stem cell survival and their expanded application in therapy. J. Cell. Biochem. 114: 2024–2031, 2013. © 2013 Wiley Periodicals, Inc.
A novel pixellated solid‐state photon detector for enhancing the everhart–thornley detector
Authors: Chuah Joon Huang , Holburn David
Published: March 2013

This article presents a pixellated solid‐state photon detector designed specifically to improve certain aspects of the existing Everhart–Thornley detector. The photon detector was constructed and fabricated in an Austriamicrosystems 0.35 µm complementary metal‐oxide‐semiconductor process technology. This integrated circuit consists of an array of high‐responsivity photodiodes coupled to corresponding low‐noise transimpedance amplifiers, a selector‐combiner circuit and a variable‐gain postamplifier. Simulated and experimental results show that the photon detector can achieve a maximum transimpedance gain of 170 dBΩ and minimum bandwidth of 3.6 MHz. It is able to detect signals with optical power as low as 10 nW and produces a minimum signal‐to‐noise ratio (SNR) of 24 dB regardless of gain configuration. The detector has been proven to be able to effectively select and combine signals from different pixels. The key advantages of this detector are smaller dimensions, higher cost effectiveness, lower voltage and power requirements and better integration. The photon detector supports pixel‐selection configurability which may improve overall SNR and also potentially generate images for different analyses. This work has contributed to the future research of system‐level integration of a pixellated solid‐state detector for secondary electron detection in the scanning electron microscope. Microsc. Res. Tech. 76:648–652, 2013. © 2013 Wiley Periodicals, Inc.
A New Reaction of Isatin, Cyclic 1,3‐Diketone, and 2‐Cyanoacetamide: A Four‐Component Synthesis of Spirooxindoles
Authors: Ghahremanzadeh Ramin , Hosseini Ghaffar , Akbarzadeh Roya , Bazgir Ayoob
Published: March 2013

A novel reaction of isatins, 2‐cyanoacetamide, and cyclic 1,3‐diketones in ethanol was reported. The reaction gave the unexpected spirooxindole ethyl carboxylates in excellent yields and the spirooxindole carboxamide was not observed.
A Simple and One‐Pot Synthesis of β‐Sultams by Using the Vilsmeier Reagent
Authors: Zarei Maaroof , Jarrahpour Aliasghar
Published: March 2013

Mild and efficient one‐pot synthesis of β‐sultams with the Vilsmeier reagent proceeded in good to excellent yield. [2 + 2] Cycloaddition of imines with sulfenes (prepared in situ) afforded the corresponding cis‐β‐sultams. Optimization of solvents, molar ratio of reagents,and temperature was performed. Toxic and corrosive compounds have been avoided in this novel method.
A Facile One‐Pot Synthesis of Pyrrolo[1, 2‐a] Indoles by Intramolecular1,3‐Dipolar Cycloaddition under Neat‐Microwave Irradiation
Authors: Hegde Subramanya , Jayashankaran Jayadevan , Ghosal Atanu , Prasanna T.S.R , Shivaraj Y. , Mohana Raju K.
Published: March 2013

A straightforward and general approach for the stereoselective synthesis of fused pyrrolo[1,2‐a] indoles frameworks from>intramolecular 1,3‐dipolar cycloaddition using N‐alkylated Baylis–Hillman derivatives is presented. It was found that the cycloaddition proceeded efficiently under microwave irradiation in solvent‐free condition to afford highly stereoselective cycloadducts in good yield.
Synthesis and Antimicrobial Activity of New Substituted 5‐(Pyridine‐3‐yl)‐1,3,4‐Thiadiazoles and Their Sugar Derivatives
Authors: El‐Sayed Wael A. , Metwally Mohamed A. , Nada Doaa S. , Mohamed Asem A. , Abdel‐Rahman Adel A.‐H.
Published: March 2013

New substituted 5‐(pyridine‐3‐yl)‐1,3,4‐thiadiazoles, their sugar hydrazones and acyclic C‐nucleoside analogs as well as the corresponding thioglycoside derivatives were synthesized. The synthesized compounds were tested for their antimicrobial activity against Escherichia coli, Bacillus subtilis, Staph aureus, Aspergillus niger, and Candida albicans The obtained results indicated that most of tested compounds exhibited moderate to high antimicrobial activity while few compounds were found to exhibit little or no activity against the tested microorganisms.
2‐Phenylethynyl‐butyltellurium attenuates amyloid‐β peptide(25–35)‐induced learning and memory impairments in mice
Authors: Souza Ana Cristina Guerra , Sari Marcel Henrique Marcondes , Pinton Simone , Luchese Cristiane , Neto José Sebastião Santos , Nogueira Cristina Wayne
Published: March 2013

Our previous study demonstrated that 2‐phenylethynyl‐butyltellurium (PEBT), an organotellurium compound, enhances memory in mice. In this study, the effects of PEBT on cognitive impairment induced by Aβ25–35 were assessed by Morris water maze and step‐down inhibitory avoidance tasks. Mice received a single intracerebroventricular injection of Aβ25–35 (3 nmol/3 μl/per site) and a daily oral administration of PEBT (1 mg/kg, for 10 days). PEBT significantly improved Aβ‐induced learning deficits on the training session in the Morris water maze. At the probe trial session, PEBT significantly decreased the escape latency and increased the number of crossings in the platform local compared with the Aβ‐treated group. PEBT significantly improved Aβ‐induced memory impairment in the step‐down inhibitory avoidance task. General locomotor activity was similar in all groups. This study showed that PEBT ameliorated the impairments of spatial and nonspatial long‐term memory evaluated on Morris water maze and step‐down inhibitory avoidance tasks, respectively. The results suggest that PEBT could be considered a candidate for the prevention of memory deficits such as those observed in Alzheimer's disease. © 2013 Wiley Periodicals, Inc.