bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma‐Free Metanephrine and Free Normetanephrine Measurement for the Diagnosis of Pheochromocytoma in Dogs
Authors: Gostelow R. , Bridger N. , Syme H.M. 
Published: January 2013

BackgroundMeasurement of plasma‐free metanephrines is the test of choice to identify pheochromocytoma in human patients.ObjectivesTo establish the sensitivity and specificity of plasma‐free metanephrine (fMN) and free normetanephrine (fNMN) concentrations to diagnose pheochromocytoma in dogs.AnimalsForty‐five client‐owned dogs (8 dogs with pheochromocytoma, 11 dogs with adrenocortical tumors, 15 dogs with nonadrenal disease, and 11 healthy dogs.)MethodsA prospective study. EDTA plasma was collected from diseased and healthy dogs and submitted forfMNandfNMNmeasurement by liquid chromatography‐tandem mass spectrometry (LC‐MS/MS).ResultsFree MN concentration (median [range]) was significantly higher in dogs with pheochromocytoma (8.15 [1.73–175.23] nmol/L) than in healthy dogs (0.95 [0.68–3.08] nmol/L;P < .01) and dogs with adrenocortical tumors (0.92 [0.25–2.51] nmol/L;P < .001), but was not different from dogs with nonadrenal disease (1.91 [0.41–6.57] nmol/L;P ≥ .05). Free NMN concentration was significantly higher in dogs with pheochromocytoma (63.89 [10.19–190.31] nmol/L) than in healthy dogs (2.54 [1.59–4.17] nmol/L;P < .001), dogs with nonadrenal disease (3.30 [1.30–10.10] nmol/L;P < .001), and dogs with adrenocortical tumors (2.96 [1.92–5.01] nmol/L);P < 0.01). When used to diagnose pheochromocytoma, afMNconcentration of 4.18 nmol/L had a sensitivity of 62.5% and specificity of 97.3%, and afNMNconcentration of 5.52 nmol/L had a sensitivity of 100% and specificity of 97.6%.Conclusions and Clinical ImportancePlasmafNMNconcentration has excellent sensitivity and specificity for the diagnosis of pheochromocytoma in dogs, whereasfMNconcentration has moderate sensitivity and excellent specificity. Measurement of plasma‐free metanephrines provides an effective, noninvasive, means of identifying dogs with pheochromocytoma.
Growth patterns and masses of the heads and necks of male and female giraffes
Authors: Mitchell G. , Roberts D. , van Sittert S. , Skinner J. D. 
Published: January 2013

AbstractWe have analyzed the growth patterns of the head and neck of 65 male and 71 female giraffes from two different populations of giraffes, and also the dimensions of 19 different components of the head and neck in 8 female and 13 male giraffes, to establish if they showed sexual dimorphism and if sexual selection for a weapon was a possible origin of the long neck of giraffes. We found that in both genders, the rate of increase in head mass was hypoallometric with respect to body mass. The rate of increase in neck length was similar in both genders and faster than the rate of increase in body mass. Increases in neck mass tend to be isometric relative to increases in body mass in both genders before puberty (c. 650 kg body mass in male and 700 kg in female giraffes), but in giraffes of greater body mass increases in neck mass are iso‐ to hyperallometric in both genders, with final neck, body and head mass being greater in male giraffes. The only significant gender difference we found for the dimensions of the 19 different head and neck components was that ossicones and skulls were heavier in mature male than in mature female giraffes, but increases in skull mass did not alter the growth pattern of head mass significantly. These data suggest that the morphology and growth patterns of the heads and necks of male and female giraffes are similar, that sexual dimorphism of the head and neck is minimal and can be attributed to secretion of sex steroids. We have concluded that there is no evidence that sexual selection was a factor in the evolution of giraffe morphology and that the long neck of giraffes did not evolve as a weapon in males. The more likely selective advantage of a long neck was improvement of access to high‐level browse.
Linking Hyperpolarization to Endothelial Cell Calcium Events in Arterioles
Authors: Dora Kim A. , Garland Chris J. 
Published: January 2013

AbstractOur understanding of the relationship between EC membrane potential and Ca2+ entry has been shaped historically by data from cells in culture. Membrane hyperpolarization was associated with raised cytoplasmic [Ca2+] ascribed to the increase in the inward electrochemical gradient for Ca2+, as ECs are generally thought to lack VGCC. Ca2+ influx was assumed to reflect the presence of an undefined Ca2+ “leak” channel, although the original research articles with isolated ECs did not elucidate which Ca2+ influx channel was involved or indeed if a transporter might contribute. Overall, these early studies left many unanswered questions, not least whether a similar mechanism operates in native ECs that are coupled to each other and, in many smaller arteries and arterioles, to the adjacent vascular SMCs via gap junctions. This review discusses whether Ca2+ leak through constitutively active EC Ca2+ channels or a more defined, gated pathway might underlie the reported link between enhanced Ca2+ entry and hyperpolarization. Electrophysiological evidence from ECs in isolation is compared with those in intact arteries and arterioles and the possible physiological relevance of EC Ca2+ entry driven by hyperpolarization discussed.
What Role for Store‐Operated Ca2+ Entry in Muscle?
Authors: Trebak Mohamed , Zhang Wei , Ruhle Brian , Henkel Matthew M. , González‐Cobos José C. , Motiani Rajender K. , Stolwijk Judith A. , Newton Rachel L. , Zhang Xuexin 
Published: January 2013

AbstractStore‐operated Ca2+ entry (SOCE) is a receptor‐regulated Ca2+ entry pathway that is both ubiquitous and evolutionarily conserved. SOCE is activated by depletion of intracellular Ca2+ stores through receptor‐mediated production of inositol 1,4,5‐trisphosphate (IP3). The depletion of endoplasmic reticulum (ER) Ca2+ is sensed by stromal interaction molecule 1 (STIM1). On store depletion, STIM1 aggregates and moves to areas where the ER comes close to the plasma membrane (PM; within 25 nm) to interact with Orai1 channels and activate Ca2+ entry. Ca2+ entry through store‐operated Ca2+ (SOC) channels, originally thought to mediate the replenishment of Ca2+ stores, participate in active downstream signaling by coupling to the activation of enzymes and transcription factors that control a wide variety of long‐term cell functions such as proliferation, growth, and migration. SOCE has also been proposed to contribute to short‐term cellular responses such as muscle contractility. While there are significant STIM1/Orai1 protein levels and SOCE activity in adult skeletal muscle, the precise role of SOCE in skeletal muscle contractility is not clear. The dependence on SOCE during cardiac and smooth muscle contractility is even less certain. Here, we will hypothesize on the contribution of SOCE in muscle and its potential role in contractility and signaling.
ShigellaIpaD has a dual role: signal transduction from the type III secretion system needle tip and intracellular secretion regulation
Authors: Roehrich A. Dorothea , Guillossou Enora , Blocker Ariel J. , Martinez‐Argudo Isabel 
Published: January 2013

SummaryType III secretion systems (T3SSs) are protein injection devices essential for the interaction of many Gram‐negative bacteria with eukaryotic cells. While Shigella assembles its T3SS when the environmental conditions are appropriate for invasion, secretion is only activated after physical contact with a host cell. First, the translocators are secreted to form a pore in the host cell membrane, followed by effectors which manipulate the host cell. Secretion activation is tightly controlled by conserved T3SS components: the needle tip proteins IpaD and IpaB, the needle itself and the intracellular gatekeeper protein MxiC. To further characterize the role of IpaD during activation, we combined random mutagenesis with a genetic screen to identify ipaD mutant strains unable to respond to host cell contact. Class II mutants have an overall defect in secretion induction. They map to IpaD's C‐terminal helix and likely affect activation signal generation or transmission. The Class I mutant secretes translocators prematurely and is specifically defective in IpaD secretion upon activation. A phenotypically equivalent mutant was found in mxiC. We show that IpaD and MxiC act in the same intracellular pathway. In summary, we demonstrate that IpaD has a dual role and acts at two distinct locations during secretion activation.
CsrA activates flhDC expression by protecting flhDC mRNA from RNase E‐mediated cleavage
Authors: Yakhnin Alexander V. , Baker Carol S. , Vakulskas Christopher A. , Yakhnin Helen , Berezin Igor , Romeo Tony , Babitzke Paul 
Published: January 2013

SummaryCsr is a conserved global regulatory system that controls expression of several hundred Escherichia coli genes. CsrA protein represses translation of numerous genes by binding to mRNA and inhibiting ribosome access. CsrA also activates gene expression, although an activation mechanism has not been reported. CsrA activates flhDC expression, encoding the master regulator of flagellum biosynthesis and chemotaxis, by stabilizing the mRNA. Computer modelling, gel mobility shift and footprint analyses identified two CsrA binding sites extending from positions 1–12 (BS1) and 44–55 (BS2) of the 198 nt flhDC leader transcript. flhD′–′lacZ expression was reduced by mutations in csrA and/or the CsrA binding sites. The position of BS1 suggested that bound CsrA might inhibit 5′ end‐dependent RNase E cleavage of flhDC mRNA. Consistent with this hypothesis, CsrA protected flhDC leader RNA from RNase E cleavage in vitro and protection depended on BS1 and BS2. Primer extension studies identified flhDC decay intermediates in vivo that correspond to in vitro RNase E cleavage sites. Deletion of these RNase E cleavage sites resulted in increased flhD′–′lacZ expression. Data from mRNA decay studies and quantitative primer extension assays support a model in which bound CsrA activates flhDC expression by inhibiting the 5′ end‐dependent RNase E cleavage pathway.
Nonstructural leaf carbohydrate dynamics of Pinus edulis during drought‐induced tree mortality reveal role for carbon metabolism in mortality mechanism
Authors: Adams Henry D. , Germino Matthew J. , Breshears David D. , Barron‐Gafford Greg A. , Guardiola‐Claramonte Maite , Zou Chris B. , Huxman Travis E. 
Published: January 2013

Summary

Vegetation change is expected with global climate change, potentially altering ecosystem function and climate feedbacks. However, causes of plant mortality, which are central to vegetation change, are understudied, and physiological mechanisms remain unclear, particularly the roles of carbon metabolism and xylem function.

We report analysis of foliar nonstructural carbohydrates (NSCs) and associated physiology from a previous experiment where earlier drought‐induced mortality of Pinus edulis at elevated temperatures was associated with greater cumulative respiration. Here, we predicted faster NSC decline for warmed trees than for ambient‐temperature trees.

Foliar NSC in droughted trees declined by 30% through mortality and was lower than in watered controls. NSC decline resulted primarily from decreased sugar concentrations. Starch initially declined, and then increased above pre‐drought concentrations before mortality. Although temperature did not affect NSC and sugar, starch concentrations ceased declining and increased earlier with higher temperatures.

Reduced foliar NSC during lethal drought indicates a carbon metabolism role in mortality mechanism. Although carbohydrates were not completely exhausted at mortality, temperature differences in starch accumulation timing suggest that carbon metabolism changes are associated with time to death. Drought mortality appears to be related to temperature‐dependent carbon dynamics concurrent with increasing hydraulic stress in P. edulis and potentially other similar species.
Belowground biotic complexity drives aboveground dynamics: a test of the soil community feedback model
Authors: Pendergast Thomas H. , Burke David J. , Carson Walter P. 
Published: January 2013

Summary

Feedbacks between soil communities and plants may determine abundance and diversity in plant communities by influencing fitness and competitive outcomes. We tested the core hypotheses of soil community feedback theory: plant species culture distinct soil communities that alter plant performance and the outcome of interspecific competition.

We applied this framework to inform the repeated dominance of Solidago canadensis in old‐field communities. In glasshouse experiments, we examined the effects of soil communities on four plant species' performance in monoculture and outcomes of interspecific competition. We used terminal restriction fragment length polymorphism (TRFLP) analysis to infer differences in the soil communities associated with these plant species.

Soil community origin had strong effects on plant performance, changed the intensity of interspecific competition and even reversed whether plant species were limited by conspecifics or heterospecifics. These plant–soil feedbacks are strong enough to upend winners and losers in classic competition models. Plant species cultured significantly different mycorrhizal fungal and bacterial soil communities, indicating that these feedbacks are likely microbiotic in nature.

In old‐fields and other plant communities, these soil feedbacks appear common, fundamentally alter the intensity and nature of plant competition and potentially maintain diversity while facilitating the dominance of So. canadensis.
Genetic architecture of flowering time differentiation between locally adapted populations of Arabidopsis thaliana
Authors: Grillo Michael A. , Li Changbao , Hammond Mark , Wang Lijuan , Schemske Douglas W. 
Published: January 2013

Summary

To gain an understanding of the genetic basis of adaptation, we conducted quantitative trait locus (QTL) mapping for flowering time variation between two winter annual populations of Arabidopsis thaliana that are locally adapted and display distinct flowering times.

QTL mapping was performed with large (n = 384) F2 populations with and without vernalization, in order to reveal both the genetic basis of a vernalization requirement and that of variation in flowering time given vernalization.

In the nonvernalization treatment, none of the Sweden parents flowered, whereas all of the Italy parents and 42% of the F2s flowered. We identified three QTLs for flowering without vernalization, with much of the variation being attributed to a QTL co‐localizing with FLOWERING LOCUS C (FLC). In the vernalization treatment, all parents and F2s flowered, and six QTLs of small to moderate effect were revealed, with underlying candidate genes that are members of the vernalization pathway. We found no evidence for a role of FRIGIDA in the regulation of flowering times.

These results contribute to a growing body of evidence aimed at the identification of ecologically relevant genetic variation for flowering time in Arabidopsis, and set the stage for functional studies to determine the link between flowering time loci and fitness.
Adaptive divergence in seed color camouflage in contrasting soil environments
Authors: Porter Stephanie S. 
Published: January 2013

Summary

Although adaptive plant population divergence across contrasting soil conditions is often driven by abiotic soil factors, natural enemies may also contribute. Cryptic matching to the native soil color is a form of defensive camouflage that seeds can use to avoid detection by seed predators.

The legume Acmispon wrangelianus occurs across a variety of gray–green serpentine soils and brown nonserpentine soils. Quantitative digital image analysis of seed and soil colors was used to test whether genetically based seed color is a closer match to the color of the native soil than to the color of other nearby soils.

Lineages bear seeds that more closely match the color of their native serpentine or nonserpentine soil type than the opposing soil type. Further, even within a soil type, lineages bear seeds with a closer color match to the soil at their native site than to other sites.

The striking concordance between seed and native soil color suggests that natural selection for locally camouflaged seed color morphs, probably driven by seed predators, may maintain adaptive divergence in pigmentation, despite the opportunity for migration between soil environments.
Fiberotomy enhances orthodontic tooth movement and diminishes relapse in a rat model
Authors: Young L. , Binderman I. , Yaffe A. , Beni L. , Vardimon A. D. 
Published: January 2013

Structured AbstractObjectivesAccelerated orthodontic tooth movement is triggered by procedures that include mucoperiosteum flap surgery and surgical scarring of cortical bone. Our aim was to test whether fiberotomy by itself will accelerate orthodontic tooth movement and diminish relapse.Materials and MethodsIn 34 Wistar rats, alveolar bone resorption and molar tooth movement were measured after fiberotomy, apical full‐thickness flap without detachment of gingiva from the roots, or no surgery. Orthodontic appliance was installed at time of surgery and activated for 14 days, generating movement of the first maxillary molar buccal and then removed.ResultsPercent of sections in which alveolar bone resorption was detected was significantly higher (p < 0.05) after fiberotomy (27%) in comparison with apical flap surgery (12%) or no surgery (6%), after 30 days. Also, at the end of active phase, the molar moved significantly faster (p < 0.01) and twice the distance after fiberotomy (0.54 ± 0.33) in comparison with apical surgery (0.26 ± 0.12) or no surgery (0.3 ± 0.09). Sixteen days after the appliance was removed, only 12% relapse was recorded in the fiberotomy group, while almost total relapse in other two groups.ConclusionWe conclude that fiberotomy solely accelerated orthodontic tooth movement and diminished relapse.
Can lower aldehyde dehydrogenase activity in saliva be a risk factor for oral cavity cancer?
Authors: Giebułtowicz J , Wroczyński P , Samolczyk‐Wanyura D 
Published: January 2013

ObjectivesSalivary ALDH3A1 protects the oral cavity from aromatic and medium‐chain aliphatic aldehydes originating from food and air pollution and generated during oxidative stress. Due to their reactivity, aldehydes may exhibit an irritating effect as well as cytotoxic, genotoxic, mutagenic and even carcinogenic effects. The aim of this study was to verify whether lower ALDH3A1 activity is a risk factor for oral cavity cancer.Subjects and methodsFasting saliva samples were collected one day before and about one week after surgery from patients with oral cancer (OCC) (n = 59), other tumours (cysts, neoplasms) (n = 108), gnathic defects and fractures (controls after the surgery) (n = 63), and from healthy volunteers (n = 116). Enzyme activity was measured using a fluorometric method.ResultsTotal ALDH3A1 activity [U g−1] in patients with OCC was statistically lower than in patients with keratocystic odontogenic tumour (KCOT) (P = 0.00697), odontogenic cysts (OC) (P < 0.00001), neoplasms (P = 0.03343) and the healthy volunteers up to and over 40 years old (P < 0.00001; P = 0.00019). The activity in the saliva of OCC after surgery was lower than in the healthy volunteers (P < 0.00001) and in the groups with fractures (P = 0.00303) and gnathic defects (P = 0.00538).ConclusionLow salivary ALDH activity may be a risk factor for oral cancer development.
Evaluation of the expression of p53,MDM2, andSUMO‐1 in oral lichen planus
Authors: Oliveira Alves MG , Balducci I , Rodarte Carvalho Y , Cabral LAG , Nunes FD , Almeida JD 
Published: January 2013

ObjectiveThe objective of this study was to compare the expression of proteins p53,MDM2, andSUMO‐1 in oral lichen planus (OLP) lesions, epithelial dysplasia, and squamous cell carcinoma.Materials and MethodsThe sample consisted of the following five groups of cheek mucosa lesions: normal mucosa (NM), inflammatory fibrous hyperplasia (IFH), lichen planus, epithelial dysplasia, and squamous cell carcinoma. The tissue samples were stained with hematoxylin‐eosin and submitted to immunohistochemistry using anti‐p53, anti‐MDM2, and anti‐SUMO‐1 antibodies.ResultsThe results of this study demonstrated similar expression of p53 andMDM2 betweenOLP, oral epithelial dysplasia and, to a lesser extent, betweenOLPand oral squamous cell carcinoma (OSCC). However, forSUMO‐1 a similar expression was observed inOLP,NM, andIFH.ConclusionsThe results demonstrated overexpression of important proteins (p53 andMDM2) related to regulatory mechanisms of apoptosis inOLP, suggesting that there is a favorable environment for malignant transformation. The expression ofSUMO‐1 inOLPwas similar toNMandIFH, suggesting that alterations of this protein occur at later stages of carcinogenesis, because important overexpression occurred in oral epithelial dysplasia andOSCC.
Regulation‐by‐information in areas of limited statehood: Lessons from thePhilippines' environmental regulation
Authors: Lee Eungkyoon , Lejano Raul P. , Connelly Robert J. 
Published: January 2013

AbstractThis research examines conditions under which environmental regulatory disclosure is more versus less likely to work, with focus on the case of thePhilippines. Two major findings arise out of a case study. First, we observe a mismatch between the nature of information and the main addressees of the disclosed information, which led the operation of the subject disclosure program to deviate from its targets. Second, this institutional deficiency has to do with the organizational culture and routine practice of the implementing agency. The second finding challenges a major justification of information‐based environmental regulation (IBER) administered in weak states and underscores the role that administrative capacity plays in making novel regulations come into effect. Contrary to the popular belief thatIBERcreates non‐governmental forces that offset a limited statehood, it may be less likely to work where state administrative capacity is weak.
Dynamics and stabilization of soil organic carbon after nineteen years of afforestation in valley‐type savannah in southwest China
Authors: Tang G. , Li K. , Sun Y. , Zhang C. 
Published: January 2013

AbstractSerious concerns about carbon (C) sequestration capacity and the stabilization of sequestered C in forested soils have emerged in the context of global climate change. The organic C in soil and in soil fractions at four sampling times in Acacia auriculiformis plantations afforested in 1991 were investigated with a combination of density fractionation and acid hydrolysis techniques. The results showed that the accumulation of C in the forested soils had accelerated because the afforestation of wasteland with A. auriculiformis. The C accumulation rates of the surface and subsurface soils averaged 0.38 and 0.17 t C/ha/yr, respectively, during the 19 yr following the afforestation. The percentage of organic C in heavy fraction relative to total soil organic C at the surface soil was 71% in 2003. This value was significantly (P < 0.05) higher than that in 2010 (68%). The chemical recalcitrant C index of light fraction was significantly (P < 0.05) higher than that of heavy fraction in 2003 regardless of soil depth, but both decreased with time. ca. 58–68% of the newly sequestered C was protected by physical mechanism, and 41–50% was transferred into the acid nonhydrolysable fraction during the 12–19 yr after the trees were planted. The chemical stability of the physically protected C remained lower than that of the unprotected C following the afforestation in the valley‐type savannah. However, both the stability values showed a decline with time.