bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel effective approach for solving nonlinear heat transfer equations
Authors: Aminikhah H. , Hemmatnezhad M.
Published: May 2012

In this paper, a novel analytic technique, namely the Laplace transform new homotopy perturbation method (LTNHPM), is applied for solving the nonlinear differential equations arising in the field of heat transfer. This approach is a new modification to the homotopy perturbation method based on the Laplace transform. Unlike the previous approach implemented by the present authors for these problems, the present method does not consider the initial approximation as a power series. The nonlinear convective–radiative cooling equation and nonlinear equation of conduction heat transfer with the variable physical properties are chosen as illustrative examples. The exact solution has been found for the first case and for the others; results with remarkable accuracy have been achieved which verify the efficiency as well as accuracy of the presented approach. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20411
Isotopic signature of nitrate in river waters of the lower Mississippi and its distributary, the Atchafalaya
Authors: BryantMason April , Xu Y. Jun , Altabet Mark
Published: May 2012

Periodic summer hypoxia occurring in the Northern Gulf of Mexico has been attributed to large nutrient inputs, especially nitrate‐nitrogen, from the Mississippi–Atchafalaya River system. The 2008 Gulf Hypoxia Action Plan calls for river corridor wetland restoration to reduce nitrate loads, but it is largely unknown how effective riverine wetland systems in the lower Mississippi River are for nitrate removal. We carried out an intensive isotope study to address this question by comparing nitrate isotopic signatures of the well‐channelized Mississippi River with those of the Atchafalaya River, which has extensive floodplains and backwater swamps. We investigated changes in δ15NNO3 and δ18ONO3 for water samples collected biweekly to monthly over a 2‐year period at the Atchafalaya River outlets (Morgan City and Wax Lake) and on the Mississippi River at Baton Rouge. In addition, in situ water quality parameters including temperature, dissolved oxygen and pH were recorded for each sampling date. Waters from both rivers showed moderately high nitrate concentration (>1 mg l−1) and undetectable (< 0.01 mg l−1) nitrite throughout the study period. The Mississippi River had slightly, but significantly higher (p=0.01) mean nitrate concentrations (1.5 mg l−1) and higher δ15NNO3 (7.7‰) than the Atchafalaya (1.1 mg l−1, 7.0‰); while no difference in δ18ONO3 (4.6‰) was found between the rivers. Flux‐weighted mean isotope values were overall lower than mean values for both the Mississippi and Atchafalaya Rivers, with a greater difference between the two rivers (7.4‰ versus 6.5‰, respectively). River flooding and hurricane storm surge also appeared to affect nitrate isotopic values. The lack of large difference in isotopic values between the Atchafalaya and Mississippi Rivers suggests that the majority of nitrate is transported through the Atchafalaya River with relatively little processing, and that riverine floodplains and wetlands are not effective sinks for nitrate, as previously assumed, because of insufficient residence time and well‐oxygenated river waters. Copyright © 2012 John Wiley & Sons, Ltd.
The ERalpha/ERbeta ratio determines oxidative stress in breast cancer cell lines in response to 17Beta‐estradiol
Authors: Nadal‐Serrano Mercedes , Sastre‐Serra Jorge , Pons Daniel Gabriel , Miró Antonia María , Oliver Jordi , Roca Pilar
Published: May 2012

The effects of 17beta‐estradiol (E2) are mediated through activation of estrogen receptors (ER): ERalpha and ERbeta. It is known that ERalpha/ERbeta ratio is higher in breast tumors than in normal tissue. Since antioxidant enzymes and uncoupling proteins (UCPs) are reactive oxygen species (ROS) production and mitochondrial biogenesis regulators, our aim was to study the E2‐effect on oxidative stress, antioxidant enzyme expression, and UCPs in breast cancer cell lines with different ERalpha/ERbeta ratios. The lower ERalpha/ERbeta ratio T47D cell line showed low ROS production and high UCP5 levels. However, the higher ERalpha/ERbeta ratio MCF‐7 cell line showed an up‐regulation of antioxidant enzymes and UCPs, yet exhibited high oxidative stress. As a result, a decrease in antioxidant enzyme activities and UCP2 protein levels, coupled with an increase in oxidative damage was found. On the whole, these results show different E2‐effects on oxidative stress regulation, modulating UCPs, and antioxidant enzymes, which were ERalpha/ERbeta ratio dependent in breast cancer cell lines. J. Cell. Biochem. 113: 3178–3185, 2012. © 2012 Wiley Periodicals, Inc.
The synthetic purine reversine selectively induces cell death of cancer cells
Authors: Piccoli Marco , Palazzolo Giacomo , Conforti Erika , Lamorte Giuseppe , Papini Nadia , Creo Pasquale , Fania Chiara , Scaringi Raffaella , Bergante Sonia , Tringali Cristina , Roncoroni Leda , Mazzoleni Stefania , Doneda Luisa , Galli Rossella , Venerando Bruno , Tettamanti Guido , Gelfi Cecilia , Anastasia Luigi
Published: May 2012

The synthetic purine reversine has been shown to possess a dual activity as it promotes the de‐differentiation of adult cells, including fibroblasts, into stem‐cell‐like progenitors, but it also induces cell growth arrest and ultimately cell death of cancer cells, suggesting its possible application as an anti‐cancer agent. Aim of this study was to investigate the mechanism underneath reversine selectivity in inducing cell death of cancer cells by a comparative analysis of its effects on several tumor cells and normal dermal fibroblasts. We found that reversine is lethal for all cancer cells studied as it induces cell endoreplication, a process that malignant cells cannot effectively oppose due to aberrations in cell cycle checkpoints. On the other hand, normal cells, like dermal fibroblasts, can control reversine activity by blocking the cell cycle, entering a reversible quiescent state. However, they can be induced to become sensitive to the molecule when key cell cycle proteins, e.g., p53, are silenced. J. Cell. Biochem. 113: 3207–3217, 2012. © 2012 Wiley Periodicals, Inc.
The clavicles of Smilodon fatalis and Panthera atrox (mammalia: Felidae) from Rancho La Brea, Los Angeles, California
Authors: Hartstone‐Rose Adam , Long Ryan C. , Farrell Aisling B. , Shaw Christopher A.
Published: May 2012

The Rancho La Brea collections at the George C. Page Museum in Los Angeles, California, contain the largest single inventory of Smilodon fatalis remains representing virtually every bone in the skeleton. Eighteen clavicles of two distinctive shapes have been recovered from historical and recent excavations at Rancho La Brea. In this study, we identify these specimens to species through comparison of their morphology and morphological variability with clavicles found in modern felids. This study includes a reevaluation of clavicles that have been previously assigned to S. fatalis, which are more likely to be those of Panthera atrox, and the description of pantherine cat clavicles. A previously undescribed sample of clavicles not only includes some of the same pantherine morph but also 10 specimens, herein assigned to S. fatalis, which are morphologically distinctive and significantly smaller than the previously described specimens. In addition, we report unexpected variations between clavicles of Panthera leo and P. tigris: the clavicles of P. leo closely resemble those of the large Rancho La Brea clavicle morph—which presumably belongs to P. atrox—thus supporting a P. leo/P. atrox clade. We report distinctive morphology of the clavicles of Acinonyx jubatus. Possible functional and phylogenic significance of felid clavicles is suggested. Diptera. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.
The expression of genes involved in glucose metabolism is affected by N‐methyl‐D‐aspartate receptor antagonism: A putative link between metabolism and an animal model of psychosis
Authors: Iasevoli Felice , Latte Gianmarco , Avvisati Livia , Sarappa Chiara , Aloj Luigi , de Bartolomeis Andrea
Published: May 2012

Psychosis has been associated with glucose metabolism impairment. Here, we explored the gene expression of hexokinase 1 (Hk1) and glucose transporter 3 (GLUT3) after the administration of a subanesthetic or a subconvulsant dose of ketamine in rats, considered to provide an animal model of psychosis. Indeed, Hk1 and GLUT3 are crucially involved in the glucose utilization in brain tissues and have also been implicated in the pathophysiology of psychosis. Quantitative brain imaging of transcripts was used to evaluate Hk1 and GLUT3 mRNA in rat brain regions related to ketamine‐induced behavioral abnormalities. Hk1 transcript was significantly increased by 50 mg/kg ketamine in cortical and subcortical areas, whereas 12 mg/kg ketamine affected Hk1 expression in the auditory cortex only. GLUT3 expression was increased by 12 mg/kg ketamine in the frontal cortex and decreased by 50 mg/kg ketamine in subcortical areas. The results show that Hk1 and GLUT3 are extensively and differentially affected by ketamine dose, supporting the view that glucose metabolism and psychosis may be causally related and suggesting that these molecules may play a role in the pathophysiology of ketamine‐induced behavioral abnormalities. © 2012 Wiley Periodicals, Inc.
Regulatory models and entrepreneurial growth: evidence from China's transition economy
Authors: Zhou Wubiao
Published: May 2012

In spite of unfavorable national regulatory policies, private entrepreneurship has grown rapidly in the early stages of the reform, partially because of the development of a local liberal regulatory environment induced by Chinese‐style market‐preserving federalism.
EFFECTS OF GRAZING INTENSITY AND BUSH ENCROACHMENT ON HERBACEOUS SPECIES AND RANGELAND CONDITION IN SOUTHERN ETHIOPIA
Authors: Angassa A.
Published: May 2012

Grazing intensity and bush encroachment are disturbance factors that may alter the floristic composition of herbaceous species. This paper investigates impacts of grazing (intensity) and bush encroachment on herbaceous species and rangeland conditions in Borana, southern Ethiopia. Herbaceous species richness and the abundance of each species were greater in the light‐ and moderate‐grazed areas than heavy‐grazed sampling plots. Similarly, herbaceous species richness was highest at an intermediate level of biomass and seems to decline as biomass increases. Among a total of 40 herbaceous species recorded, 20 per cent were tolerant of grazing, whereas the remaining 80 per cent were highly susceptible to heavy grazing. In both encroached and non‐encroached sampling plots, species richness varied from three to six species 0·25 m−2. Overall, herbaceous species richness and abundance, in relation to grazing gradient, might disclose a better picture of the effect of grazing on individual herbaceous species. As species richness seems to decline under heavy grazing intensity, low to intermediate grazing levels may promote and conserve key forage species in savanna grazing lands. Copyright © 2012 John Wiley & Sons, Ltd.
Cationic Copolyelectrolytes: Online Monitoring of the Synthesis and Subsequent Copolymer Characterization
Authors: Li Zheng , Alb Alina M.
Published: May 2012

Kinetics of copolymerization reactions of diallyldimethylammonium chloride (DADMAC) and dimethyl acrylamide (DMA) in aqueous solvent is studied, with highlights on features that control many aspects of the polymeric materials behavior throughout and post‐synthesis. The aim of this study is twofold; first, to offer a method to study the impact of the incorporation of the cationic DADMAC on the composition drift, molecular mass of the copolyelectrolyte, and on the polyelectrolyte behavior by monitoring in real time the copolymerization reactions with a neutral monomer under different conditions. Additionally, it is meant to make the transition toward the next step, controlling the reaction kinetics during designed semi‐batch experiments designed to achieve the average mass and composition distributions desired.
Acute effects of weight training on glycaemia in type 1 diabetes
Authors: Chisholm John , Kilbride Lynn , Charlton Jacqui , John McKnight
Published: May 2012

Exercise is regarded as a potential strategy to assist in the management of blood glucose in people with type 1 diabetes. However, currently there is little evidence‐based information detailing the acute effects weight training has on glycaemia in type 1 diabetes. The aim of this review is to identify studies investigating the acute effects of weight training on blood glucose levels in type 1 diabetes.

A search of Cumulative Index to Nursing and Allied Health Literature, Cochrane, Medline and SPORTDiscus databases was conducted. A systematic review of these studies was undertaken to address the issue.

After fulfilling the inclusion criteria, eight articles were retrieved. The individual studies reported comparatively different results.

Study findings from this review are inconclusive regarding the acute glycaemic response to weight training exercise. Analyses of the intervention studies highlight that weight training may increase, minimally affect or decrease post‐exercise glycaemia in type 1 diabetes. It is likely that the heterogeneity regarding the weight training methods used among the studies, as well as the pre/post‐exercise insulin and carbohydrate intake of the study participants have impacted on the findings.

There remains a gap in the evidence base to inform health care professionals of the likely acute glycaemic response to weight training exercise. Problems in managing patient glycaemia may arise due to erroneous insulin and carbohydrate alterations based on unfounded and anecdotal‐based guidance. The studies highlighted in this review have reported some of the potential effects that weight training may have on glycaemia. Copyright © 2012 John Wiley & Sons.
Synthesis of graft terpolymers by addition reaction of amino‐terminated polyether to poly(methacrylate)s bearing five‐membered cyclic dithiocarbonate moieties and application of the graft terpolymers as modifiers for wool
Authors: Hirata Mitsuhiro , Watanabe Takeshi , Ochiai Bungo , Endo Takeshi
Published: May 2012

Graft terpolymers bearing polyether side chains and poly(methacrylate) stems were synthesized by the graft‐onto reaction of monoamino‐terminated poly(PO9‐co‐EO1) to poly{[5‐(methacryloyloxy)methyl‐1,3‐oxathiolane‐2‐thione]‐co‐n‐butyl methacrylate} [poly(DTCMMA‐co‐BuMA)]. The grafting reaction proceeded via the nucleophilic addition of the terminal amino groups to the five‐membered cyclic dithiocarbonate moieties giving thiol moieties, although the grafting efficiency was low (9–34%) due to the steric hindrance of the side chains. The Tg values of the poly{[DTCMMA‐graft‐poly(PO9‐co‐EO1)]‐co‐BuMA} ranged 27–47 °C, depending on the amounts of flexible poly(PO9‐co‐EO1) chains introduced lowering the Tg values. Poly{[DTCMMA‐graft‐poly(PO9‐co‐EO1)]‐co‐BuMA}s bearing thiol groups were applied for the modification of wool via the disulfide exchange reaction. The modified wool had better dye ability toward a pigment from safflower than the original wool owing to the hydrophilic nature of poly{[DTCMMA‐graft‐poly(PO9‐co‐EO1)]‐co‐BuMA} introduced. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
HDL cholesterol: the importance of targeting low plasma levels
Authors: Patel Dipesh
Published: May 2012

Several studies have shown the inverse relationship between low HDL cholesterol levels and increased risk of CHD that is independent of LDL cholesterol levels. Dr Patel discusses the effectiveness of the currently available drug treatments in raising low HDL‐C.
Improvement of Liver Function in Humans Using a Mixture of Schisandra Fruit Extract and Sesamin
Authors: Chiu Hui‐Fang , Chen Tzy‐Yen , Tzeng Yu‐Te , Wang Chin‐Kun
Published: May 2012

This was a randomized, parallel, and placebo‐controlled study. Forty subjects were divided into a test group and a placebo group. The study was focused on the potential effects of a mixture of Schisandra fruit extract and sesamin (hereinafter called ‘SCH’) in the subjects with borderline high levels (40–60 U/L) of alanine aminotransferase (ALT) or aspartate aminotransferase (AST). Twenty subjects taking SCH (four tablets per day) and 20 subjects taking a placebo (four tablets per day) were studied. The effects of SCH on ALT, AST, total bilirubin, direct bilirubin, free radical levels, total antioxidant status, glutathione peroxidase, glutathione reductase, and the lag time for low‐density lipoprotein oxidation were determined. The total test period was 5 months. Intervention of SCH clearly reduced the levels of ALT and AST, but it made no change in the total bilirubin and direct bilirubin. Intake of SCH also greatly increased the antioxidant capacity and decreased the values of thiobarbituric acid reactive substances, total free radicals, and superoxide anion radicals in the plasma. The activities of glutathione peroxidase and reductase in the erythrocytes were significantly increased. In addition, the lag time for low‐density lipoprotein oxidation, an inflammatory marker, was evidently increased. Fatty liver was found to have been significantly improved in this study. SCH proved to have the effects of antioxidation and improving liver function. Copyright © 2012 John Wiley & Sons, Ltd.
Investigation into the Genotoxicity of Water Extracts from Hypoxis Species and a Commercially Available Hypoxis Preparation
Authors: Verschaeve L. , Mertens B. , Ndhlala A. R. , Anthonissen R. , Gorissen B. , Van Staden J.
Published: May 2012

We performed an in vitro evaluation of the genotoxic potential of water extracts from four Hypoxis species (Hypoxis hemerocallidea, H. colchicifolia, H. rigidula, H. acuminata) and a commercial preparation thereof using the neutral red uptake (NRU) assay, the alkaline comet assay and the cytome assay in human hepatoma HepG2 cells. The relative cytotoxicity of these samples was established by determining their NI50 values (50% inhibition of NRU), and these results were used for dose‐finding in genotoxicity tests. None of the tested extracts were identified as genotoxic in both the alkaline comet assay and cytome assay. Copyright © 2012 John Wiley & Sons, Ltd.
Detection of melamine in infant formula and grain powder by surface‐assisted laser desorption/ionization mass spectrometry
Authors: Hsieh Yi‐Ting , Chen Wen‐Tsen , Tomalová Iva , Preisler Jan , Chang Huan‐Tsung
Published: May 2012

We have developed a method for the determination of melamine (MEL), ammeline (AMN), and ammelide (AMD) by surface‐assisted laser desorption/ionization mass spectrometry (SALDI‐MS) using gold nanoparticles (Au NPs). The major peaks for MEL, AMN, and AMD at m/z 127.07, 128.05, and 129.04 are assigned to the [MEL + H]+, [AMN + H]+, and [AMD + H]+ ions. Because the three tested compounds adsorb weakly onto the surfaces of the Au NPs through Au–N bonding, they can be easily concentrated from complex samples by applying a simple trapping/centrifugation process. The SALDI‐MS method provides limits of detection of 5, 10, and 300 nM for MEL, AMN, and AMD, respectively, at a signal‐to‐noise ratio of 3. The signal variation for 150‐shot average spectra of the three analytes within the same spot was 15%, and the batch‐to‐batch variation was 20%. We have validated the practicality of this approach by the analysis of these three analytes in infant formula and grain powder. This simple and rapid SALDI‐MS approach holds great potential for screening of MEL in foods. Copyright © 2012 John Wiley & Sons, Ltd.
How do young firms manage product portfolio complexity? The role of absorptive capacity and ambidexterity
Authors: Fernhaber Stephanie A. , Patel Pankaj C.
Published: May 2012

Building a complex portfolio of products can be beneficial for young firms due to increased sales growth and competitiveness. Yet, the benefits from product portfolio complexity (PPC) are often outweighed by rising costs, leading to an inverted U‐shaped relationship between PPC and performance. Recent research has called for an increased understanding of how firms are able to better manage higher levels of PPC. We suggest that absorptive capacity and ambidexterity are vital to enhancing the benefits and mitigating the costs of increasing PPC. Using a sample of 215 young high technology firms, we find support for positive moderating effects of absorptive capacity and ambidexterity on the inverted U‐shaped relationship between PPC and firm performance. Copyright © 2012 John Wiley & Sons, Ltd.
Starch of diverse Mexican rice cultivars: physicochemical, structural, and nutritional features
Authors: Chávez‐Murillo Carolina E. , Méndez‐Montealvo Guadalupe , Wang Ya‐Jane , Bello‐Pérez Luis A.
Published: May 2012

Structure‐function relationship of rice starch is scarce in the literature. Starch was isolated from diverse Mexican rice varieties and their swelling power (SP), soluble solids (ss), thermal and pasting properties, XRD pattern, in vitro starch digestibility, and AP chain‐length distribution were evaluated. Rice starches with low SP at 60°C had higher temperature and enthalpy of gelatinization. The peak viscosity of rice starches ranged between 2426 and 3519 cP, and the samples presented high values for setback due to the AM content. Rice starches presented the typical A‐type XRD pattern with crystallinity values between 32.7 and 36.3%. Rice starches presented high amounts of short chains (A and B1), and differences were found among the cultivars. AM content for rice starches ranged between 18.4 and 22.9%, and the main fraction recorded by HPSEC was the Fraction III (short chains) with values around 60%. The uncooked rice starch samples presented high values of slowly digestible starch (SDS) and rapidly digestible starch (RDS), and differences were found among the cultivars. In cooked samples decreased SDS and increased RDS and RS. Onset temperature and enthalpy of gelatinization were correlated with the percentage of A‐chains and an opposite pattern was found with the percentage of B1 chains. AP structural characteristics affect the functional, physicochemical, and digestibility properties of rice starches.
Exosome-Mediated Transfer of miR-133b from Multipotent Mesenchymal Stromal Cells to Neural Cells Contributes to Neurite Outgrowth
Authors: Xin Hongqi , Li Yi , Buller Ben , Katakowski Mark , Zhang Yi , Wang Xinli , Shang Xia , Zhang Zheng Gang , Chopp Michael
Published: May 2012

Multipotent mesenchymal stromal cells (MSCs) have potential therapeutic benefit for the treatment of neurological diseases and injury. MSCs interact with and alter brain parenchymal cells by direct cell-cell communication and/or by indirect secretion of factors and thereby promote functional recovery. In this study, we found that MSC treatment of rats subjected to middle cerebral artery occlusion (MCAo) significantly increased microRNA 133b (miR-133b) level in the ipsilateral hemisphere. In vitro, miR-133b levels in MSCs and in their exosomes increased after MSCs were exposed to ipsilateral ischemic tissue extracts from rats subjected to MCAo. miR-133b levels were also increased in primary cultured neurons and astrocytes treated with the exosome-enriched fractions released from these MSCs. Knockdown of miR-133b in MSCs confirmed that the increased miR-133b level in astrocytes is attributed to their transfer from MSCs. Further verification of this exosome-mediated intercellular communication was performed using a cel-miR-67 luciferase reporter system and an MSC-astrocyte coculture model. Cel-miR-67 in MSCs was transferred to astrocytes via exosomes between 50 and 100 nm in diameter. Our data suggest that the cel-miR-67 released from MSCs was primarily contained in exosomes. A gap junction intercellular communication inhibitor arrested the exosomal microRNA communication by inhibiting exosome release. Cultured neurons treated with exosome-enriched fractions from MSCs exposed to 72 hours post-MCAo brain extracts significantly increased the neurite branch number and total neurite length. This study provides the first demonstration that MSCs communicate with brain parenchymal cells and may regulate neurite outgrowth by transfer of miR-133b to neural cells via exosomes.
Prenatal diagnosis of isolated total anomalous pulmonary venous connection: a series of 10 cases
Authors: Laux D. , Fermont L. , Bajolle F. , Boudjemline Y. , Stirnemann J. , Bonnet D.
Published: May 2012

Objectives

To report on a series of 10 fetuses with prenatally diagnosed isolated total anomalous pulmonary venous connection (TAPVC), focusing on echocardiographic features leading to diagnosis, assess accuracy of prenatal diagnosis and describe postnatal outcome.

Methods

In this review of our experience of prenatal diagnosis of isolated TAPVC, we analyzed retrospectively medical records and fetal echocardiography findings in all cases with prenatal diagnosis of isolated TAPVC delivered between 1 January 2001 and 1 October 2011 at a tertiary referral center, paying special attention to echocardiographic signs that led to referral.

Results

During the study period, 95 infants with isolated TAPVC were seen at the center. Initially, expert fetal echocardiography identified 14 fetuses with isolated TAPVC. Prenatal diagnosis was made at a mean gestational age of 31 (range, 25–37) weeks. Ten true‐positive cases of TAPVC were confirmed after birth. The remaining four were considered false‐positive cases: two had normal heart with left superior vena cava to coronary sinus, one had partial anomalous venous connection and one was lost to follow‐up. Of the 85 diagnosed postnatally with TAPVC, only one had been seen prenatally by an expert cardiac sonographer. Echocardiographic signs leading to referral were related to pulmonary venous connection in half of the cases. Other suspected defects which led to referral were ostium prium atrial defect (n = 3), left–right asymmetry (n = 1), abnormal mitral valve (n = 1) and hepatic vascular malformation (n = 1). All infants with TAPVC underwent surgery. There was one postoperative death and nine survivors, with a mean follow‐up of 31 (range, 2–104) months.

Conclusion

Fetal diagnosis of isolated TAPVC is challenging even for experts. Echocardiographic anomalies may appear late in gestation. New tools should be proposed to identify abnormal venous drainage at the screening level. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Can angle of progression in pregnant women before onset of labor predict mode of delivery?
Authors: Levy R. , Zaks S. , Ben‐Arie A. , Perlman S. , Hagay Z. , Vaisbuch E.
Published: May 2012

Objectives

The angle of progression (AOP), measured by transperineal ultrasound, has been used to assess fetal head descent during labor. Our aim was to assess whether, before onset of labor, parous women have a narrower AOP than do nulliparous women and if a narrow AOP is associated with a higher rate of Cesarean delivery.

Methods

In this prospective, observational study, we performed transperineal ultrasound in pregnant women not yet in labor at ≥ 39 weeks' gestation who delivered within 1 week of sonography. The AOP was compared as follows: in nulliparous women, between those who had a Cesarean section and those who delivered vaginally; and among women who delivered vaginally, between those who were nulliparous and those who were parous.

Results

Included in the study were 100 nulliparous and 71 parous women. Among those who delivered vaginally (n = 161), the median AOP before onset of labor was narrower in parous than in nulliparous women (98° (interquartile range (IQR)), 90–107° vs 104° (IQR, 97–113°), P < 0.001). Among the 100 nulliparous women, (1) the median AOP before onset of labor was narrower in those who went on to deliver by Cesarean section (n = 9) than in those delivered vaginally (n = 91) (90° (IQR, 85.5–93.5°) vs 104° (IQR, 97–113°), P < 0.001); (2) an AOP ≥ 95° (derived from the receiver–operating characteristics curve) was associated with vaginal delivery in 99% of women; and (3) 89% (8/9) of women who delivered by Cesarean section had an AOP < 95°. Among the 71 parous women, only one delivered by Cesarean section and all of those with an AOP < 95° delivered vaginally.

Conclusion

A narrow AOP (< 95°) in non‐laboring nulliparous women at term is associated with a high rate of Cesarean delivery. Parous women have a narrower AOP than do nulliparous women before the onset of labor; however, unlike in nulliparous women, a narrow AOP in parous women does not appear to be associated with Cesarean delivery and most parous women with such an angle go on to deliver vaginally. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
The etiology and molecular genetics of human pigmentation disorders
Authors: Baxter Laura L. , Pavan William J.
Published: May 2012

Pigmentation, defined as the placement of pigment in skin, hair, and eyes for coloration, is distinctive because the location, amount, and type of pigmentation provides a visual manifestation of genetic heterogeneity in pathways regulating the pigment‐producing cells, melanocytes. The scope of this genetic heterogeneity in humans ranges from normal to pathological pigmentation phenotypes. Clinically, normal human pigmentation encompasses a variety of skin and hair color as well as punctate pigmentation such as melanocytic nevi (moles) or ephelides (freckles), while abnormal human pigmentation exhibits markedly reduced or increased pigment levels, known as hypopigmentation and hyperpigmentation, respectively. Elucidation of the molecular genetics underlying pigmentation has revealed genes important for melanocyte development and function. Furthermore, many pigmentation disorders show additional defects in cells other than melanocytes, and identification of the genetic insults in these disorders has revealed pleiotropic genes, where a single gene is required for various functions in different cell types. Thus, unravelling the genetics of easily visualized pigmentation disorders has identified molecular similarities between melanocytes and less visible cell types/tissues, arising from a common developmental origin and/or shared genetic regulatory pathways. Herein we discuss notable human pigmentation disorders and their associated genetic alterations, focusing on the fact that the developmental genetics of pigmentation abnormalities are instructive for understanding normal pathways governing development and function of melanocytes. WIREs Dev Biol 2013, 2:379–392. doi: 10.1002/wdev.72

For further resources related to this article, please visit the WIREs website.

This article is a U.S. Government work, and as such, is in the public domain in the United States of America.

The authors declare no conflicts of interest.
Hydrogels for in vivo‐like three‐dimensional cellular studies
Authors: DeVolder Ross , Kong Hyun‐Joon
Published: May 2012

Extensive efforts have been made to understand the effects of extracellular microenvironments on phenotypic activities for a wide array of stem, progenitor, and precursor cells. Hydrogels have emerged as invaluable platforms for examining the effects of extracellular matrix (ECM) properties on cell activities because of their several advantageous features. Specifically, hydrogels are unique materials that enable cell studies in three‐dimensional (3D) environments, similar to in vivo environments. Recently, there have been increasing efforts to assemble cell‐encapsulating hydrogels; however, hydrogel design strategies for 3D cell cultures have not been systematically discussed to date. Therefore, this review article summarizes current hydrogel designs for 3D cell culture studies and further discusses current challenges and potential resolutions for enhancing the controllability of hydrogel properties and microstructures. The hydrogels discussed herein include those of natural polymers (e.g., collagen, fibrinogen, alginate, and hyaluronic acids), synthetic polymers [e.g., poly(ethylene glycol) (PEG) and its derivatives], and mixtures of natural and synthetic polymers. We envision that hydrogels that enable 3D studies will greatly assist in the understanding of emergent cell behaviors, and ultimately become important biomedical tools for enhancing the quality of in vitro drug screening and clinical treatments. WIREs Syst Biol Med 2012 doi: 10.1002/wsbm.1174

This article is categorized under:

Biological Mechanisms > Cell Fates

Models of Systems Properties and Processes > Cellular Models

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models

Developmental Biology > Stem Cell Biology and Regeneration
Microwave radiation and reactor design influence microbial communities during methane fermentation
Authors: Cydzik-Kwiatkowska Agnieszka , Zieliński Marcin , Jaranowska Paulina
Published: May 2012

The effect of reactor design and method of heating on the efficiency of methane fermentation and composition of microbial communities, especially methanogenic Archaea, were determined. The research was carried out using submerge- and trickling-bed reactors fed with wastewater and the heat supply into the reactors included a convection heating method and microwave radiation. The polymerase chain reaction-denaturing gradient gel electrophoresis and relative real-time PCR were used in order to assess the biofilm communities. The best fermentation results and the highest abundance of methanogenic Archaea in biomass were observed in microwave heated trickling-bed reactors. The research proved that in reactors of identical design, the application of microwaves enabled a higher fermentation efficiency to be obtained and simultaneously increased the diversity of methanogenic Archaea communities that favors process stability. All the identified sequences of Archaea belonged to Methanosarcina sp., suggesting that species from this genera are susceptible to non-thermal effects of microwaves. There were no effects from microwaves on the bacterial communities in both types of reactors, however, the bacterial species composition varied in the reactors of different design.
Intramedullary nails for pediatric diaphyseal femur fractures in older, heavier children: Early results
Authors: Reynolds Richard A. K. , Legakis Julie E. , Thomas Ronald , Slongo Theddy F. , Hunter James B. , Clavert Jean-Michel
Published: May 2012

Purpose

A common treatment for pediatric femur fractures is intramedullary nail (IMN) insertion. Elastic stable intramedullary nails (ESINs) are often used for these procedures in heavier patients, but the potential for complications and malunion is greater. We describe here a rigid IMN specifically designed for adolescents, the adolescent lateral entry femoral nail (ALFN). The purpose of this study was to compare the recovery and complications for patients treated with ESINs to those treated with the ALFN.

Methods

Our study design was a retrospective cohort study. We performed a review of medical records of 22 children ages 10–17 requiring surgical fixation of a femur fracture for a 2½-year period. Patients selected for the study had traumatic diaphyseal femur fractures and were treated with ESINs without end-caps or ALFNs. Our analyses evaluated injury, surgical, and outcome information for all patients.

Results

Twenty-two patients were eligible for inclusion and were divided into two groups according to their treatment: the ESIN group with 7 patients and the ALFN group with 15 patients. We then performed a comparison of complications and recovery for these patients. The mean time to full weight-bearing was significantly less for the ALFN group (4.1 weeks; SD, 2.2), than the ESIN group (9.4 weeks; SD 3.9). There was no statistical difference in the incidence of major or minor complications.

Conclusions

Older, heavier pediatric patients treated for femur fracture with ALFNs had a shorter recovery time than similar patients treated with ESINs. However, the outcomes for both groups were satisfactory.
Risques prostatiques de la testostérone : nouveau retour du balancier?
Authors: Buvat J.
Published: May 2012

Depuis les années 1940, la testostérone (T) est réputée dangereuse pour la prostate, bien que sans preuve solide. Les études longitudinales ne montrent pas de corrélation entre taux de T et incidence des cancers de la prostate (CaP), dont les formes graves sont au contraire associées à des taux faibles de cette hormone. Les essais cliniques randomisés contre placebo de traitement par la T n’ont pas montré d’augmentation de l’incidence du CaP dans les groupes T. Ces données rassurantes ont conduit certains à prescrire des traitements de substitution androgénique à des hommes porteurs de néoplasies intra-épithéliales prostatiques, ou précédemment traités pour un CaP de bon pronostic, ou sous surveillance active pour un tel cancer non traité, sans qu’apparaisse un risque élevé de progression ou de récidive du CaP sous ce traitement. Il ne fait pourtant aucun doute que la prostate normale et son cancer, au moins dans ses formes évoluées, sont faits de tissus androgénodépendants. Ces apparentes contradictions pourraient s’expliquer, outre par la possibilité d’une très faible diffusion de la T circulante dans le tissu prostatique, par l’hypothèse d’une saturation des récepteurs androgéniques prostatiques dès des niveaux très bas de T circulante, proches des taux de castration, expliquant qu’une augmentation de la T au-delà de ce niveau ne puisse pas stimuler le tissu prostatique. Quelques publications récentes d’évolution de CaP sous traitement androgénique, persistant parfois à l’arrêt de ce traitement, montrent qu’on ne peut pas généraliser les résultats très favorables des études précédentes. Des données objectives suggèrent aussi que le niveau de saturation du récepteur androgénique prostatique pourrait être en réalité proche de la limite inférieure des taux physiologiques de T. Il faut donc rester prudent avant d’élargir les indications du traitement par la T chez les hommes avec antécédent de CaP. Seules des études randomisées à grande échelle, en double insu contre placebo, permettront de se faire une idée exacte des risques auxquels expose ce traitement.
Omega 3 fatty acids and inborn errors of metabolism
Authors: Gil-Campos Mercedes , Sanjurjo Crespo Pablo
Published: May 2012

A number of studies are investigating the role ofn-3 polyunsaturated fatty acids in children with metabolic inborn errors, while the effects on visual and brain development in premature infants and neonates are well known. However, their function incertain chronic neurological, inflammatory and metabolic disorders is still under study. Standards should be established to help identify the need of docosahexaenoic acid supplementation in conditions requiring a restricted diet resulting in an altered metabolism system, and find scientific evidence on the effects of such supplementation. This study reviews relevant published literature to propose adequaten-3 intake or supplementation doses for different ages and pathologies. The aim of this review is to examine the effects of long chain polyunsaturated fatty acids supplementation in preventing cognitive impairment or in retarding its progress, and to identify nutritional deficiencies, in children with inborn errors of metabolism. Trials were identified from a search of the Cochrane and MEDLINE databases in 2011. These databases include all major completed and ongoing double-blind, placebo-controlled, randomized trials, as well as all studies in which omega-3 supplementation was administered to children with inborn errors, and studies assessing omega-3 fatty acids status in plasma in these pathologies. Although few randomized controlled trials met the inclusion criteria of this review, some evidenced that most of children with inborn errors are deficient in omega-3 fatty acids, and demonstrated that supplementation might improve their neural function, or prevent the progression of neurological impairment. Nontheless, further investigations are needed on this issue.
Influence of marinen-3 polyunsaturated fatty acids on immune function and a systematic review of their effects on clinical outcomes in rheumatoid arthritis
Authors: Miles Elizabeth A. , Calder Philip C.
Published: May 2012

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease of the joints and bones. Then-6 polyunsaturated fatty acid (PUFA) arachidonic acid (ARA) is the precursor of inflammatory eicosanoids which are involved in RA. Some therapies used in RA target ARA metabolism. Marinen-3 PUFAs (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) found in oily fish and fish oils decrease the ARA content of cells involved in immune responses and decrease the production of inflammatory eicosanoids from ARA. EPA gives rise to eicosanoid mediators that are less inflammatory than those produced from ARA and both EPA and DHA give rise to resolvins that are anti-inflammatory and inflammation resolving, although little is known about these latter mediators in RA. Marinen-3 PUFAs can affect other aspects of immunity and inflammation relevant to RA, including dendritic cell and T cell function and production of inflammatory cytokines and reactive oxygen species, although findings for these outcomes are not consistent. Fish oil has been shown to slow the development of arthritis in animal models and to reduce disease severity. A number of randomised controlled trials of marinen-3 PUFAs have been performed in patients with RA. A systematic review included 23 studies. Evidence is seen for a fairly consistent, but modest, benefit of marinen-3 PUFAs on joint swelling and pain, duration of morning stiffness, global assessments of pain and disease activity, and use of non-steroidal anti-inflammatory drugs.
Mineral chemistry and thermobarometry of the staurolite-chloritoid schists from Poshtuk, NW Iran
Authors: SAKI ADEL , MOAZZEN MOHSSEN , OBERHÄNSLI ROLAND
Published: May 2012

The Poshtuk metapelitic rocks in northwestern Iran underwent two main phases of regional and contact metamorphism. Microstructures, textural features and field relations indicate that these rocks underwent a polymetamorphic history. The dominant metamorphic assemblage of the metapelites is garnet, staurolite, chloritoid, chlorite, muscovite and quartz, which grew mainly syntectonically during the later contact metamorphic event. Peak metamorphic conditions of this event took place at 580 °C and ~3–4 kbar, indicating that this event occurred under high-temperature and low-pressure conditions (HT/LP metamorphism), which reflects the high heat flow in this part of the crust. This event is mainly controlled by advective heat input through magmatic intrusions into all levels of the crust. These extensive Eocene metamorphic and magmatic activities can be associated with the early Alpine Orogeny, which resulted in this area from the convergence between the Arabian and Eurasian plates, and the Cenozoic closure of the Tethys oceanic tract(s).
Economic Development in Preindustrial Japan, 1859–1894
Authors: Miyamoto Mataji , Sakudō Yōtarō , Yasuba Yasukichi
Published: May 2012

In this paper we shall try to do three things: first, to describe the economic conditions which prevailed before the arrival of Commodore Perry; second, to survey the economic policy of the Shogunate and the Meiji Government in responding to the impact of the opening up of the country; and third, to make a few general comments on some selected aspects of Japan's economic development between 1859, when three Japanese ports were opened to foreign trade, and 1894, when the Sino-Japanese War broke out. The latter date is chosen because it fairly clearly marks off the beginning of the rapid development of the modern sector of the Japanese economy.
Self-control, Selfishness and Mutilation: How ‘Medical’ is Self-Injury Anyway?
Authors: Chaney Sarah
Published: May 2012

Self-inflicted injury, or ‘self-harm’, has been a topic of much debate in recent years. The media in the Western world has tended to portray the issue as an increasing ‘trend’, relating it to various contemporary concerns, including the so-called ‘celebrity culture’ and urban decline. The past decade in the UK has seen the publication of various clinical guidelines, a National Inquiry into Self-Harm in young people, and almost continual media speculation. In the last two decades of the nineteenth century, speculation also occurred around ‘self-mutilation’, an area newly defined by alienists (asylum psychiatrists). This topic has received little historical attention; yet, had ‘self-harm’ been on the agenda in the 1970s and '80s, nineteenth-century self-mutilation would no doubt have been presented as part of a discourse on professionalisation, in which the creation of a new psychiatric category was presented as part of the ‘medicalisation’ of psychiatry, through observation and classification within asylums. More recently, a changing historiography has led to histories of self-harm being located within a schema for ‘making up’ people, such as attention to the development of a patient profile for the apparently new behaviour of ‘delicate self cutting’ in the mid-twentieth century. This article builds on this concept to explore broader social issues around the creation of the concept of ‘self-mutilation’, which help to explain the occurrence of an impetus for ‘making up people’ in a particular period or culture. In particular, the impetus is related here to changing ideas of what constituted the ‘self’ and the relation of the individual to society in the late nineteenth century.
‘Very Sore Nights and Days’: The Child’s Experience of Illness in Early Modern England, c.1580–1720
Authors: Newton Hannah
Published: May 2012

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.
Physician Resistance and the Forging of Public Healthcare: A Comparative Analysis of the Doctors’ Strikes in Canada and Belgium in the 1960s
Authors: Marchildon Gregory P. , Schrijvers Klaartje
Published: May 2012

Organised medicine in a number of advanced industrial countries resisted the post-war trend toward more state involvement in the funding and organisation of medical care. While there were eight doctors’ strikes during the peak of reform efforts in the 1960s, two of the most prolonged and bitter struggles took place in Canada and Belgium. This comparative analysis of the two strikes highlights the philosophy, motives, and strategies of organised medicine in resisting state-led reform efforts. Although historical and institutional contexts in the two countries differed, organised medicine in Canada and Belgium thought and responded in very similar ways to the perceived threat of medical insurance reform. While the perception of who won and who lost the respective doctors’ strikes differed, the ultimate impact on the trajectory of public healthcare on the medical profession was remarkably similar. In both countries, the strike would have a long-standing impact on future reform efforts, particularly efforts to reform physician remuneration in order to facilitate more effective primary healthcare.