bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of Ion Transport in Control of Apoptotic Cell Death
Authors: Lang Florian , Hoffmann Else K. 
Published: June 2012

AbstractCell shrinkage is a hallmark and contributes to signaling of apoptosis. Apoptotic cell shrinkage requires ion transport across the cell membrane involving K+channels, Cl−or anion channels, Na+/H+exchange, Na+,K+,Cl−cotransport, and Na+/K+ATPase. Activation of K+channels fosters K+exit with decrease of cytosolic K+concentration, activation of anion channels triggers exit of Cl−, organic osmolytes, and HCO3−. Cellular loss of K+and organic osmolytes as well as cytosolic acidification favor apoptosis. Ca2+entry through Ca2+‐permeable cation channels may result in apoptosis by affecting mitochondrial integrity, stimulating proteinases, inducing cell shrinkage due to activation of Ca2+‐sensitive K+channels, and triggering cell‐membrane scrambling. Signaling involved in the modification of cell‐volume regulatory ion transport during apoptosis include mitogen‐activated kinases p38, JNK, ERK1/2, MEKK1, MKK4, the small G proteins Cdc42, and/or Rac and the transcription factor p53. Osmosensing involves integrin receptors, focal adhesion kinases, and tyrosine kinase receptors. Hyperosmotic shock leads to vesicular acidification followed by activation of acid sphingomyelinase, ceramide formation, release of reactive oxygen species, activation of the tyrosine kinase Yes with subsequent stimulation of CD95 trafficking to the cell membrane. Apoptosis is counteracted by mechanisms involved in regulatory volume increase (RVI), by organic osmolytes, by focal adhesion kinase, and by heat‐shock proteins. Clearly, our knowledge on the interplay between cell‐volume regulatory mechanisms and suicidal cell death is still far from complete and substantial additional experimental effort is needed to elucidate the role of cell‐volume regulatory mechanisms in suicidal cell death. © 2012 American Physiological Society.Compr Physiol2:2037‐2061, 2012.
K+Channels: Function‐Structural Overview
Authors: González Carlos , Baez‐Nieto David , Valencia Ignacio , Oyarzún Ingrid , Rojas Patricio , Naranjo David , Latorre Ramón 
Published: June 2012

AbstractPotassium channels are particularly important in determining the shape and duration of the action potential, controlling the membrane potential, modulating hormone secretion, epithelial function and, in the case of those K+channels activated by Ca2+, damping excitatory signals. The multiplicity of roles played by K+channels is only possible to their mammoth diversity that includes at present 70 K+channels encoding genes in mammals. Today, thanks to the use of cloning, mutagenesis, and the more recent structural studies using x‐ray crystallography, we are in a unique position to understand the origins of the enormous diversity of this superfamily of ion channels, the roles they play in different cell types, and the relations that exist between structure and function. With the exception of two‐pore K+channels that are dimers, voltage‐dependent K+channels are tetrameric assemblies and share an extremely well conserved pore region, in which the ion‐selectivity filter resides. In the present overview, we discuss in the function, localization, and the relations between function and structure of the five different subfamilies of K+channels: (a) inward rectifiers, Kir; (b) four transmembrane segments‐2 pores, K2P; (c) voltage‐gated, Kv; (d) the Slo family; and (e) Ca2+‐activated SK family, SKCa. © 2012 American Physiological Society.Compr Physiol2:2087‐2149, 2012.
Gap Junctions
Authors: Nielsen Morten Schak , Nygaard Axelsen Lene , Sorgen Paul L. , Verma Vandana , Delmar Mario , Holstein‐Rathlou Niels‐Henrik 
Published: June 2012

AbstractGap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell‐cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society.Compr Physiol2:1981‐2035, 2012.
Mechanical Properties of the Upper Airway
Authors: Strohl Kingman P. , Butler James P. , Malhotra Atul 
Published: June 2012

AbstractThe importance of the upper airway (nose, pharynx, and larynx) in health and in the pathogenesis of sleep apnea, asthma, and other airway diseases, discussed elsewhere in the Comprehensive Physiology series, prompts this review of the biomechanical properties and functional aspects of the upper airway. There is a literature based on anatomic or structural descriptions in static circumstances, albeit studied in limited numbers of individuals in both health and disease. As for dynamic features, the literature is limited to studies of pressure and flow through all or parts of the upper airway and to the effects of muscle activation on such features; however, the links between structure and function through airway size, shape, and compliance remain a topic that is completely open for investigation, particularly through analyses using concepts of fluid and structural mechanics. Throughout are included both historically seminal references, as well as those serving as signposts or updated reviews. This article should be considered a resource for concepts needed for the application of biomechanical models of upper airway physiology, applicable to understanding the pathophysiology of disease and anticipated results of treatment interventions. © 2012 American Physiological Society.Compr Physiol2:1853‐1872, 2012.
Coping with Thermal Challenges: Physiological Adaptations to Environmental Temperatures
Authors: Tattersall Glenn J. , Sinclair Brent J. , Withers Philip C. , Fields Peter A. , Seebacher Frank , Cooper Christine E. , Maloney Shane K. 
Published: June 2012

AbstractTemperature profoundly influences physiological responses in animals, primarily due to the effects on biochemical reaction rates. Since physiological responses are often exemplified by their rate dependency (e.g., rate of blood flow, rate of metabolism, rate of heat production, and rate of ion pumping), the study of temperature adaptations has a long history in comparative and evolutionary physiology. Animals may either defend a fairly constant temperature by recruiting biochemical mechanisms of heat production and utilizing physiological responses geared toward modifying heat loss and heat gain from the environment, or utilize biochemical modifications to allow for physiological adjustments to temperature. Biochemical adaptations to temperature involve alterations in protein structure that compromise the effects of increased temperatures on improving catalytic enzyme function with the detrimental influences of higher temperature on protein stability. Temperature has acted to shape the responses of animal proteins in manners that generally preserve turnover rates at animals' normal, or optimal, body temperatures. Physiological responses to cold and warmth differ depending on whether animals maintain elevated body temperatures (endothermic) or exhibit minimal internal heat production (ectothermic). In both cases, however, these mechanisms involve regulated neural and hormonal over heat flow to the body or heat flow within the body. Examples of biochemical responses to temperature in endotherms involve metabolic uncoupling mechanisms that decrease metabolic efficiency with the outcome of producing heat, whereas ectothermic adaptations to temperature are best exemplified by the numerous mechanisms that allow for the tolerance or avoidance of ice crystal formation at temperatures below 0°C. © 2012 American Physiological Society.Compr Physiol2:2151‐2202, 2012.
Kinetic Study of Thermal 1,3‐Dipolar Cycloaddition of Azomethine Ylides by Using Differential Scanning Calorimetry
Authors: Mancebo‐Aracil Juan , Muñoz‐Guillena María J. , Such‐Basáñez Ion , Sansano‐Gil José M. 
Published: June 2012

AbstractThe kinetics of 1,3‐dipolar cycloaddition involving azomethine ylides, generated from thermal 1,2‐prototropy of the corresponding imino ester, employing differential scanning calorimetry (DSC), is surveyed. Glycine and phenylalanine derived imino esters have different behavior. The first one prefers reacting with itself at 75 °C, rather than with the dipolarophile. However, the α‐substituted imino ester gives the cycloadduct at higher temperatures. Thermal dynamic analysis, by using 1H NMR spectroscopy, of the neat reaction mixture of the glycine derivative reveals the presence of signals corresponding to the dipole in small abundance. The non‐isothermal and isothermal DSC curves of the cycloaddition of phenylalaninate and diisobutyl fumarate are obtained from freshly prepared samples. The application of known kinetic models and mathematical multiple non‐linear regressions (NLR) allow the determintion and comparison of Ea, lnA, reaction orders, and reaction enthalpy values. Finally a rate equation for each different temperature studied can be established for this particular thermal cycloaddition.
Effectiveness of GH isoform differential immunoassay for detecting rhGH doping on application of various growth factors
Authors: Okano Masato , Nishitani Yasunori , Sato Mitsuhiko , Kageyama Shinji 
Published: June 2012

The analytical method for detecting growth hormone (GH) doping, the so‐called GH isoform differential immunoassay, is currently approved by the World Anti‐Doping Agency (WADA).Anti‐doping laboratories often face challenges by athletes' lawyers and need to have various types of scientific evidence against the claim that the adverse analytical finding (AAF) result was caused by excess ectopic or abnormal excretion. In this work, a population study of Japanese athletes (255 male and 256 female) and administration studies of recombinant human GH (rhGH) in Japanese females were conducted to confirm the applicability of GH isoform differential immunoassay. The present paper describes the effectiveness of the GH isoform differential immunoassay under abnormal excretion of endogenous GH as determined by administration studies of GH releasing hormone (GHRH(1–44)) and insulin‐like growth factor‐1 (IGF‐1). No false positive findings were found in Japanese athletes. The GH isoform differential immunoassays could detect application of rhGH for approximately 12–24 h. The administration of GHRH(1–44) and IGF‐1 as well as ghrelin receptor agonists did not affect the isoform ratio (no false positives). We conclude that the GH isoform differential immunoassay is a highly specific method for detecting rhGH doping. Subject‐based profiling (i.e. athlete biological passport) very likely will represent a highly sensitive approach for detecting rhGH doping. Copyright © 2012 John Wiley & Sons, Ltd.
Psychotropic medication use in anorexia nervosa between 1997 and 2009
Authors: Fazeli Pouneh K. , Calder Genevieve L. , Miller Karen K. , Misra Madhusmita , Lawson Elizabeth A. , Meenaghan Erinne , Lee Hang , Herzog David , Klibanski Anne 
Published: June 2012

AbstractObjective:Despite a lack of data demonstrating benefit, psychotropic medications are frequently prescribed for patients with anorexia nervosa.Method:We studied 525 women (18–54 years of age) with anorexia nervosa who presented to the Clinical Research Center at the Massachusetts General Hospital between January 1997 and December 2009. For this analysis, participants were a priori divided into two groups based on date of presentation (Group I: participants presenting between 1997 and 2002; Group II: participants presenting between 2003 and 2009).Results:Overall, 53% of participants reported current use of any psychotropic medication; 48.4% reported use of an antidepressant and 13% reported use of an antipsychotic. Twice as many participants in Group II (18.5%) reported using atypical antipsychotics as compared to Group I (8.9%) (p = 0.002).Discussion:A majority of participants with anorexia nervosa report using psychotropic medications despite lack of data supporting their efficacy. These data are concerning given the known adverse effects of these medications. © 2012 by Wiley Periodicals, Inc. (Int J Eat Disord 2012)
Effect of Lactobacillus plantarum P‐8 on lipid metabolism in hyperlipidemic rat model
Authors: Bao Yan , Wang Zhanli , Zhang Yong , Zhang Jiachao , Wang Lifeng , Dong Ximei , Su Fang , Yao Guoqiang , Wang Shuiquan , Zhang Heping 
Published: June 2012

AbstractProbiotics have been reported to play an important role in the prevention of metabolic disorders. We recently identified a novel probiotic strain Lactobacillus plantarum (L. plantarum) P‐8. The objective of this study was to determine the effects of L. plantarum P‐8 on lipid metabolism of rats fed with high fat diet. All experimental rats were divided into three groups: control group, model group, and L. plantarum P‐8 group. Changes in serum lipid levels, hepatic lipid deposition, serum oxidative stress‐related parameters, activities of liver function marker enzymes, organ indices, gut microflora, and fecal lipids were assessed. Compared with model group, L. plantarum P‐8 exhibited hypolipidemic effects by lowering serum total cholesterol (TC), triglyceride (TG), and low‐density lipoprotein cholesterol levels, accompanied with elevation of high‐density lipoprotein cholesterol level. L. plantarum P‐8 also exerted beneficial effects against high‐fat diet‐induced oxidative stress, curtailed the accumulation of liver lipids and protected healthy liver function. Moreover, L. plantarum P‐8 was able to regulate intestinal bacteria and enhance the fecal excretion of TC, TG, and bile acid. These findings indicate that L. plantarum P‐8 may represent a potential therapeutic agent for controlling hyperlipidemia.
Vegetable oil cast resins via click chemistry: Effects of cross‐linkers
Authors: Hong Jian , Shah Bipin K. , Petrović Zoran S. 
Published: June 2012

AbstractPolymerization of azidated castor, canola, corn, soybean, and linseed oils with two diynes under thermal click chemistry conditions (without a solvent or a catalyst) yielded fully cross‐linked polymers (1–10) with similar density. The use of an aromatic diyne (1,4‐diethynylbenzene) as a cross‐linker resulted in polymers (1–5) that showed higher glass transition and strength and lower swelling, water absorption, and sol fraction than corresponding polymers (6–10) resulting from an aliphatic diyne (1,7‐octadiyne). These polymers exhibited behaviors ranging from soft rubbers to hard plastics.Practical applications: Vegetable oil cast resins prepared by click chemistry are potentially useful electroinsulating materials as potting or encapsulating compounds since no by‐products are generated.
AFB1‐induced mutagenesis of the gpt gene in AS52 cells
Authors: Wattanawaraporn Roongtiwa , Kim Min Young , Adams Jillian , Trudel Laura J. , Woo Leslie L. , Croy Robert G. , Essigmann John M. , Wogan Gerald N. 
Published: June 2012

AbstractAflatoxin B1 (AFB1) is a potent mutagen and an important risk factor for hepatocellular carcinoma (HCC) in humans. Transgenic mouse strains and cells in culture have been used to detect different types of mutations caused by AFB1 and investigate the molecular determinants of their location and frequency. The AFB1 mutational spectrum in the gpt gene was markedly different in AS52 cells compared with the liver in gpt delta B6C3F1 transgenic mice. The results demonstrate the importance of metabolism, chromosomal location, transcription and selection conditions on mutational spectra. Environ. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.
The seismic demand hazard and importance of the conditioning intensity measure
Authors: Bradley Brendon A. 
Published: June 2012

SUMMARYThe seismic demand hazard, which gives the rate/probability of exceeding a specified level of seismic demand/response in a given exposure period, is a key measure used to quantify the seismic performance of structures. Because of its simplicity in implementation, the intensity measure (IM)‐based approach is the most common method for computation of the seismic demand hazard. One observed detrimental consequence of the IM‐based approach is that the practical computation of the seismic demand hazard appears to be dependent on the IM used in its computation. This manuscript demonstrates theoretically that the seismic demand hazard for a particular structure at a specific location is unique irrespective of the conditioning IM used in its computation. More importantly, it is demonstrated that this theoretical result can be consistently obtained in a practical context via a six‐step process based around the selection of ground motion records using the generalised conditional intensity measure (GCIM) approach. Copyright © 2012 John Wiley & Sons, Ltd.
Stochastic subspace identification for output‐only modal analysis: application to super high‐rise tower under abnormal loading condition
Authors: Liu Yi‐Cheng , Loh Chin‐Hsiung , Ni Yi‐Qing 
Published: June 2012

SUMMARYThe objective of this paper is to develop an online system parameter estimation technique from the response measurements through using the recursive covariance‐driven stochastic subspace identification (SSI‐COV) approach. In developing the recursive SSI‐COV, to avoid time‐consumption of singular value decomposition in recursive SSI, the extended instrumental variable version of the projection approximation subspace tracking method is used in SSI‐COV. Besides, to reduce the effect of noise on the results of identification, the preprocessing of data using recursive singular spectrum analysis technique is also presented to remove the noise contaminant measurements to enhance the stability of data analysis. On the basis of the proposed method, both the ambient vibration and seismic response data of a tower (Canton Tower) are used to observe the time‐varying system natural frequencies of a tower from its operating condition. Results from using off‐line SSI‐COV method under normal operating condition are also presented. Comparison on the identified time‐varying dynamic characteristics of the tower under normal operating condition and earthquake response of distanced earthquake event is discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Exclusion of the 750‐kb genetically unstable region at Xq27 as a candidate locus for prostate malignancy in HPCX1‐linked families
Authors: Kouprina Natalay , Lee Nicholas C. O. , Pavlicek Adam , Samoshkin Alexander , Kim Jung‐Hyun , Lee Hee‐Sheung , Varma Sudhir , Reinhold William C. , Otstot John , Solomon Greg , Davis Sean , Meltzer Paul S. , Schleutker Johanna , Larionov Vladimir 
Published: June 2012

AbstractSeveral linkage studies provided evidence for the presence of the hereditary prostate cancer locus, HPCX1, at Xq27‐q28. The strongest linkage peak of prostate cancer overlies a variable region of ∼750 kb at Xq27 enriched by segmental duplications (SDs), suggesting that the predisposition to prostate cancer may be a genomic disorder caused by recombinational interaction between SDs. The large size of SDs and their sequence similarity make it difficult to examine this region for possible rearrangements using standard methods. To overcome this problem, direct isolation of a set of genomic segments by in vivo recombination in yeast (a TAR cloning technique) was used to perform a mutational analysis of the 750 kb region in X‐linked families. We did not detect disease‐specific rearrangements within this region. In addition, transcriptome and computational analyses were performed to search for nonannotated genes within the Xq27 region, which may be associated with genetic predisposition to prostate cancer. Two candidate genes were identified, one of which is a novel gene termed SPANXL that represents a highly diverged member of the SPANX gene family, and the previously described CDR1 gene that is expressed at a high level in both normal and malignant prostate cells, and mapped 210 kb of upstream the SPANX gene cluster. No disease‐specific alterations were identified in these genes. Our results exclude the 750‐kb genetically unstable region at Xq27 as a candidate locus for prostate malignancy. Adjacent regions appear to be the most likely candidates to identify the elusive HPCX1 locus. © 2012 Wiley Periodicals, Inc.
Comprehensive DNA methylation analysis of benign and malignant adrenocortical tumors
Authors: Fonseca Annabelle L. , Kugelberg Johan , Starker Lee F. , Scholl Ute , Choi Murim , Hellman Per , Åkerström Göran , Westin Gunnar , Lifton Richard P. , Björklund Peyman , Carling Tobias 
Published: June 2012

AbstractThe molecular pathogenesis of benign and malignant adrenocortical tumors (ACT) is incompletely clarified. The role of DNA methylation in adrenocortical tumorigenesis has not been analyzed in an unbiased, systematic fashion. Using the Infinium HumanMethylation27 BeadChip, the DNA methylation levels of 27,578 CpG sites were investigated in bisulfite‐modified DNA from 6 normal adrenocortical tissue samples, 27 adrenocortical adenomas (ACA), and 15 adrenocortical carcinomas (ACC). Genes involved in cell cycle regulation, apoptosis, and transcriptional regulation of known or putative importance in the development of adrenal tumors showed significant and frequent hypermethylation. Such genes included CDKN2A, GATA4, BCL2, DLEC1, HDAC10, PYCARD, and SCGB3A1/HIN1. Comparing benign versus malignant ACT, a total of 212 CpG islands were identified as significantly hypermethylated in ACC. Gene expression studies of selected hypermethylated genes (CDKN2A, GATA4, DLEC1, HDAC10, PYCARD, SCGB3A1/HIN1) in 6 normal and 16 neoplastic adrenocortical tissues (10 ACA and 6 ACC), displayed reduced gene expression in benign and malignant ACT versus normal adrenocortical tissue. Treatment with 5‐aza‐2′‐deoxycytidine of adrenocortical cancer H‐295R cells increased expression of the hypermethylated genes CDKN2A, GATA4, DLEC1, HDAC10, PYCARD, and SCGB3A1/HIN1. In conclusion, the current study represents the first unbiased, quantitative, genome‐wide study of adrenocortical tumor DNA methylation. Genes with altered DNA methylation patterns were identified of putative importance to benign and malignant adrenocortical tumor development. © 2012 Wiley Periodicals, Inc.