bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronic Inhibition of ERK1/2 Signaling Improves Disordered Bone and Mineral Metabolism in Hypophosphatemic (Hyp) Mice
Authors: Zhang Martin Y. H. , Ranch Daniel , Pereira Renata C. , Armbrecht Harvey J. , Portale Anthony A. , Perwad Farzana
Published: February 2012

The X-linked hypophosphatemic (Hyp) mouse carries a loss-of-function mutation in the phex gene and is characterized by hypophosphatemia due to renal phosphate (Pi) wasting, inappropriately suppressed 1,25-dihydroxyvitamin D [1,25(OH)2D] production, and rachitic bone disease. Increased serum fibroblast growth factor-23 concentration is responsible for the disordered metabolism of Pi and 1,25(OH)2D. In the present study, we tested the hypothesis that chronic inhibition of fibroblast growth factor-23-induced activation of MAPK signaling in Hyp mice can reverse their metabolic derangements and rachitic bone disease. Hyp mice were administered the MAPK inhibitor, PD0325901 orally for 4 wk. PD0325901 induced a 15-fold and 2-fold increase in renal 1α-hydroxylase mRNA and protein abundance, respectively, and thereby higher serum 1,25(OH)2D concentrations (115 ± 13 vs. 70 ± 16 pg/ml, P < 0.05), compared with values in vehicle-treated Hyp mice. With PD0325901, serum Pi levels were higher (5.1 ± 0.5 vs. 3 ± 0.2 mg/dl, P < 0.05), and the protein abundance of sodium-dependent phosphate cotransporter Npt2a, was greater than in vehicle-treated mice. The rachitic bone disease in Hyp mice is characterized by abundant unmineralized osteoid bone volume, widened epiphyses, and disorganized growth plates. In PD0325901-treated Hyp mice, mineralization of cortical and trabecular bone increased significantly, accompanied by a decrease in unmineralized osteoid volume and thickness, as determined by histomorphometric analysis. The improvement in mineralization in PD0325901-treated Hyp mice was confirmed by microcomputed tomography analysis, which showed an increase in cortical bone volume and thickness. These findings provide evidence that in Hyp mice, chronic MAPK inhibition improves disordered Pi and 1,25(OH)2D metabolism and bone mineralization.
Adoptive Transfer of Antithyrotropin Receptor (TSHR) Autoimmunity from TSHR Knockout Mice to Athymic Nude Mice
Authors: Nakahara Mami , Johnson Kristian , Eckstein Anja , Taguchi Ryo , Yamada Masanobu , Abiru Norio , Nagayama Yuji
Published: February 2012

We have recently shown that wild type mice are highly tolerant, whereas thyrotropin receptor (TSHR) knockout (KO) mice are susceptible to immunization with the mouse TSHR, the autoantigen in Graves' disease. However, because TSHR KO mice lack the endogenous TSHR, Graves-like hyperthyroidism cannot be expected to occur in these mice. We therefore performed adoptive transfer of splenocytes from TSHR KO mice into nude mice expressing the endogenous TSHR. Anti-TSHR autoantibodies were detected in approximately 50 % recipient mice 4 wk after adoptive transfer of splenocytes (5 × 107/mouse) from TSHR KO mice immunized with adenovirus expressing mTSHR A subunit and persisted for 24 wk. Depletion of regulatory T cells by anti-CD25 antibody in the donor mice increased successful transfer rates without increasing antibody levels. Some recipient mice showed transient increases in thyroid-stimulating antibodies and T4 levels 4–8 wk after transfer, but many became thyroid-blocking antibody positive and hypothyroid 24 wk later. Adoptive transfer of splenocytes from naïve TSHR KO mice transiently induced very low antibody titers when the recipient mice were treated with anticytotoxic lymphocyte antigen 4 and antiprogrammed cell death 1 ligand 1 antibodies for 8 wk after transfer. Histologically, macrophages infiltrated the retrobulbar adipose tissues and extraocular muscles in a small fraction of the recipients. Our findings demonstrate successful adoptive transfer of anti-TSHR immune response from TSHR KO mice to nude mice. Although the recipient mice developed only transient and infrequent hyperthyroidism, followed by eventual hypothyroidism, induction of orbital inflammation suggests the possible role of anti-TSHR immune response for Graves' orbitopathy.
Role of Hypothalamic Proopiomelanocortin Neuron Autophagy in the Control of Appetite and Leptin Response
Authors: Quan Wenying , Kim Hyun-Kyong , Moon Eun-Yi , Kim Su Sung , Choi Cheol Soo , Komatsu Masaaki , Jeong Yeon Taek , Lee Moon-Kyu , Kim Kwang-Won , Kim Min-Seon , Lee Myung-Shik
Published: February 2012

Autophagy is a catabolic cellular process involving the degradation of the cell's own components. Although the role of autophagy of diverse tissues in body metabolism has been investigated, the importance of autophagy in hypothalamic proopiomelanocortin (POMC) neurons, key regulators of energy balance, has not been addressed. The role of autophagy in leptin sensitivity that is critical for the control of body weight and appetite has also not been investigated. We produced mice with specific deletion of autophagy-related 7 (Atg7), an essential autophagy gene, in hypothalamic POMC neurons (Atg7ΔPOMC mice). Atg7 expression was deficient in the arcuate nucleus of the hypothalamus of Atg7ΔPOMC mice. p62, a specific substrate of autophagy, accumulated in the hypothalamus of Atg7ΔPOMC mice, which colocalized with ubiquitin. Atg7ΔPOMC mice had increased body weight due to increased food intake and decreased energy expenditure. Atg7ΔPOMC mice were not more prone to diet-induced obesity compared with control mice but more susceptible to hyperglycemia after high-fat diet. The ability of leptin to suppress fasting-elicited hyperphagia and weight gain during refeeding was attenuated in Atg7ΔPOMC mice. Deficient autophagy did not significantly affect POMC neuron number but impaired leptin-induced signal transducer and activation of transcription 3 activation. Our findings indicate a critical role for autophagy of POMC neurons in the control of energy homeostasis and leptin signaling.
Role of GABA Release From Leptin Receptor-Expressing Neurons in Body Weight Regulation
Authors: Xu Yuanzhong , O'Brien William G. , Lee Cheng-Chi , Myers Martin G. , Tong Qingchun
Published: February 2012

It is well established that leptin regulates energy balance largely through isoform B leptin receptor-expressing neurons (LepR neurons) in the brain and that leptin activates one subset of LepR neurons (leptin-excited neurons) while inhibiting the other (leptin-inhibited neurons). However, the neurotransmitters released from LepR neurons that mediate leptin action in the brain are not well understood. Previous results demonstrate that leptin mainly acts on γ-aminobutyric acid (GABA)ergic neurons to reduce body weight, and that leptin activates proopiomelanocortin neuron activity by reducing GABA release onto these neurons, suggesting a body weight-promoting role for GABA released from leptin-inhibited neurons. To directly examine the role of GABA release from LepR neurons in body weight regulation, mice with disruption of GABA release specifically from LepR neurons were generated by deletion of vesicular GABA transporter in LepR neurons. Interestingly, these mice developed mild obesity on chow diet and were sensitive to diet-induced obesity, which were associated with higher food intake and lower energy expenditure. Moreover, these mice showed blunted responses in both food intake and body weight to acute leptin administration. These results demonstrate that GABA plays an important role in mediating leptin action. In combination with the previous studies that leptin reduces GABA release onto proopiomelanocortin neurons through leptin-inhibited neurons and that disruption of GABA release from agouti gene-related protein neurons, one subset of LepR-inhibited neurons, leads to a lean phenotype, our results suggest that, under our experimental conditions, GABA release from leptin-excited neuron dominates over leptin-inhibited ones.
Making It Old: The Victorian/Modern Divide in Twentieth-Century American Poetry
Authors: Ehlers Sarah
Published: February 2012

Focusing on the work of Harriet Monroe and Selma Walden, two Chicago writers who never fully identified with their literary milieus, this essay complicates the perceived divide between the Victorian and the modern, the old and the new. In his 1900 American Anthology, Monroe’s friend and mentor Edmund Clarence Stedman dubbed the turn of the century an “interval of twilight” for American poetry. Subsequent critics have perhaps read this narrative of decline too literally and regarded the supposed interregnum as a sign of progress toward modernism. This essay takes a different approach: understanding narratives of poetry’s twilight as strategic fictions that idealize, preserve, and recirculate the poetry of an earlier period. It views Monroe and Walden as productive symptoms of a critical tendency to incorporate narratives about Victorian poetry into narratives about modernism. Considered together, Monroe and Walden demonstrate how the Victorian had complex afterlives in twentieth-century America. Their works show how the tension between the Victorian and the modern reemerged during the twentieth century, playing out on different levels of culture.
sizzled function and secreted factor network dynamics
Authors: Shi Jianli , Zhang Huarong , Dowell Robin D. , Klymkowsky Michael W.
Published: February 2012

Studies on the role of the E-box binding transcription factor Snail2 (Slug) in the induction of neural crest by mesoderm (Shi et al., 2011) revealed an unexpected increase in the level of sizzled RNA in the dorsolateral mesodermal zone (DMLZ) of morphant Xenopus embryos. sizzled encodes a secreted protein with both Wnt and BMP inhibitor activities. Morpholino-mediated down-regulation of sizzled expression in one cell of two cell embryos or the C2/C3 blastomeres of 32-cell embryos, which give rise to the DLMZ, revealed decreased expression of the mesodermal marker brachyury and subsequent defects in neural crest induction, pronephros formation, and muscle patterning. Loss of sizzled expression led to decreases in RNAs encoding the secreted Wnt inhibitor SFRP2 and the secreted BMP inhibitor Noggin; the sizzled morphant phenotype could be rescued by co-injection of RNAs encoding Noggin and either SFRP2 or Dickkopf (a mechanistically distinct Wnt inhibitor). Together, these observations reveal that sizzled, in addition to its established role in dorsal-ventral patterning, is also part of a dynamic BMP and Wnt signaling network involved in both mesodermal patterning and neural crest induction.
Phase-contrast X-ray microtomography of mouse fetus
Authors: Hoshino Masato , Uesugi Kentaro , Yagi Naoto
Published: February 2012

A phase-contrast X-ray microtomography system using the Talbot imaging has been built at the SPring-8 synchrotron radiation facility. This system has much higher density resolution than absorption-based X-ray microtomography. The tomographic sections of formalin-fixed mouse fetuses obtained with this method clearly depict various organs without any staining at a pixel resolution of up to 5 µm. Since this technique allows us to obtain three-dimensional structural information without sectioning, it will be particularly useful to examine anomalies that take place during development. It can be also used to quantitatively measure volume and mass of organs during development.
Diagnostic accuracy of computed tomography and histopathology in the diagnosis of usual interstitial pneumonia
Authors: Aaløkken Trond Mogens , Naalsund Anne , Mynarek Georg , Berstad Audun Elnaes , Solberg Steinar , Strøm Erik H , Scott Helge , Kolbenstvedt Alf , Søyseth Vidar
Published: February 2012

Background

The relative clinical benefit of histopathology and computed tomography (CT) in patients with idiopathic interstitial pneumonia (IIP) is under debate.

Purpose

To analyze thin-section CT features and histopathologic findings in patients with usual interstitial pneumonia (UIP) in the clinical context of idiopathic pulmonary fibrosis (IPF), and to evaluate and compare diagnostic accuracy of the two methods among patients with an appropriate spectrum of IIP.

Material and Methods

The study included 91 patients (49 men; mean age 53.2 years; median follow-up 7.2 years) with clinically suspected interstitial lung disease. All underwent surgical lung biopsy and thin-section CT. Two independent readers retrospectively assessed the CT images for the extent and pattern of abnormality and made a first-choice diagnosis. Two pathologists retrospectively assessed the histopathologic slides. In 64 patients with IIP, a retrospective composite reference standard identified 41 patients with UIP. CT characteristics of UIP and IIPs other than UIP were compared with univariate and multivariate analyses.

Results

There was good agreement between the readers for the correct first-choice CT diagnosis of UIP (κ = 0.79). The sensitivity, specificity, and positive predictive value of the CT diagnosis of UIP were 63%, 96%, and 96%, respectively. The sensitivity, specificity, and positive predictive value of the histological diagnosis of UIP were 73%, 74%, and 83%, respectively. The CT feature that best differentiated UIP from IIPs other than UIP was the extent of reticular pattern (odds ratio, 5.1).

Conclusion

Surgical lung biopsy may not be warranted in patients with thin-section CT diagnosis of UIP.
A novel minimal invasive closed chest myocardial ischaemia reperfusion model in rhesus monkeys (Macaca mulatta): improved stability of cardiorespiratory parameters
Authors: Portier K G , Broillet A , Rioufol G , Lepage O M , Depecker M , Taborik F , Tranquart F , Contamin H
Published: February 2012

The aim of this study was to report the cardiorespiratory events observed during coronary artery occlusion and reperfusion in a minimally invasive closed chest myocardial occlusion–reperfusion model in rhesus monkeys. We hypothesized that a minimally invasive technique may lead to fewer cardiac arrhythmias and complications. Eight male rhesus macaques 10–15 kg and 10–15 years old were sedated with ketamine (2 mg/kg), midazolam (1.3 mg/kg), atropine (0.01 mg/kg) and buprenorphine 0.02 mg/kg intramuscularly. Etomidate 1–2 mg/kg was injected intravenously to allow tracheal intubation. Anaesthesia was maintained with isoflurane. Pulse oximetry, electrocardiogram (ECG), heart rate, mean arterial blood pressure (MAP), inspired isoflurane fractions (FIISO) and core temperature were recorded every 10 min. The coronary artery occlusion was induced by a balloon-tipped catheter advanced via the femoral artery into the left anterior descending artery and inflated to completely occlude the vessel for 20–50 min (IT) before reperfusion. Sequences of elevated ST segment, QRS complex prolongation, ventricular premature complexes and ventricular fibrillation were observed with a lower incidence than previously described in the literature. IT was (min: 17; max: 50) min long. FIISO was lower than the minimal alveolar concentration in these species. Hypotension (MAP < 70 mmHg) and hypothermia ( T°C < 36°C) were observed in all macaques. This minimally invasive closed chest model was successful in providing better cardiorespiratory physiological parameters than reported in previous models. The benefit (achieving ischaemia) versus risk (lethal arrhythmia) of the duration of the coronary occlusion should be considered.
Less invasive blood sampling in the animal laboratory: clinical chemistry and haematology of blood obtained by the Triatominae bug Dipetalogaster maximus
Authors: Markvardsen S N , Kjelgaard-Hansen M , Ritz C , Sørensen D B
Published: February 2012

Dipetalogaster maximus (Dipmax), a blood-sucking bug belonging to the family Reduviidae, has been used to obtain blood samples, for example for clinical chemistry and haematology, in a variety of zoo animals and wildlife. Using this bug allows stress-free blood sampling as the bug is able to draw blood without the mammal noticing the bug. In laboratory animal science, the need for blood samples from unstressed animals may arise, especially in animal behaviour research. The use of Dipmax bugs may prove a valuable tool for this purpose. To validate the method, we compared an array of standard blood parameters sampled from New Zealand White rabbits, sampled either by the use of bugs or by the conventional method; puncture of vena auricularis caudalis. The overall hypothesis was that there was no significant difference in clinical chemistry and haematological parameters between the bug method and the conventional method . A total of 17 clinical parameters as well as 12 haematological parameters were measured and compared in New Zealand White rabbits. The results showed that for 13 of these 29 analysed parameters, the bug method and the conventional method did not give significantly different results, and the obtained results were thus directly comparable. For the remaining parameters the obtained results were significantly different. However, all parameters were measurable in the bug samples. The influences of the bug metabolism on these parameters are discussed.
Hygienic monitoring of Mongolian gerbils: which mouse viruses should be included?
Authors: Bleich Eva-M , Keubler Lydia M , Smoczek Anna , Mähler Michael , Bleich André
Published: February 2012

The Mongolian gerbil ( Meriones unguiculatus) serves as an animal model for a wide range of diseases. A practical limitation in its use is the definition of the hygienic status, as not much is known about viruses that potentially infect gerbils and might be transmitted to other rodents. As successful re-derivation was recently described for gerbils, we now aimed at investigating which mouse viruses induce seroconversion in gerbils and might be transmitted to mice. Gerbils were inoculated with viral agents of mice and co-housed with mouse contact sentinels. Seroconversion in gerbils was observed after oronasal inoculation with Sendai virus (SeV), mammalian orthoreovirus serotype 3 (Reo-3) and rotavirus A (RV-A, EDIM), seroconversion to RV-A also in sentinel mice. Pneumonia virus of mice (PVM) was not detected by serology but by polymerase chain reaction in gerbils and respective sentinel mice. No seroconversion towards or transmission of murine hepatitis virus, murine norovirus, minute virus of mice or mouse cytomegalovirus was detected. Anti-gerbil IgG antibodies did not increase sensitivity of indirect immunofluorescence (IFA) compared with anti-mouse IgG. In conclusion, seroconversion to SeV, Reo-3 and RV-A as well as transmission of RV-A and PVM indicate that these agents should be included in health monitoring of gerbils. Furthermore, anti-mouse IgG is suitable as a secondary antibody for IFA with gerbil serum.
Thymomas II
Authors: Moran Cesar A. , Walsh Garrett , Suster Saul , Kaiser Larry
Published: February 2012

We present 250 cases of thymomas with emphasis on their clinical staging and follow-up. The patients were 120 males and 130 females between the ages of 13 and 92 years. Surgical resection was performed and histopathologic material evaluated in every case. Grossly, the tumors resected varied in size from 3 to 20 cm in greatest diameter. According to our proposed staging system, 31 cases were stage 0, 128 were stage I, 70 stage II, and 21 stage III at the time of resection. Histologically, approximately 53% of thymomas were of mixed histologic types. Follow-up information ranging from 1 to 16 years was obtained, showing significant statistical P values of .044 and .016 for overall and recurrence-free survival, respectively. We consider that our proposed staging system offers better stratification of cases and improved histologic definitions for proper staging of cases of thymoma.
The Spectrum of Hematologic Malignancies Involving the Pancreas
Authors: Rock Jonathan , Bloomston Mark , Lozanski Gerard , Frankel Wendy L.
Published: February 2012

Hematologic malignancies often involve the pancreas, causing potential diagnostic pitfalls and, rarely, potentially avoidable surgical resection. We review the spectrum of hematologic malignancies involving the pancreas and describe features useful in preoperative distinction from adenocarcinoma.

Archived clinical, pathologic, and radiologic data (1965 to present) for hematologic malignancies involving the pancreas were reviewed and compared with the data for 157 surgically resected pancreatic adenocarcinomas. Of 42 cases, 27 (64%) were clinically “suspicious” for hematologic malignancies. Of the remaining 15 cases, 4 patients underwent resection for presumed pancreatic adenocarcinoma. Isolated pancreatic masses proved most difficult to identify clinically. Significant factors in distinguishing hematologic malignancies from adenocarcinoma included history of hematologic malignancy, young age, large tumor size, low CA19-9 level, B symptoms, and lack of jaundice or diabetes mellitus.

Various hematologic malignancies involve the pancreas, most commonly diffuse large B-cell lymphoma. Pancreatic masses are usually correctly identified clinically. Preoperative and operative sampling is strongly recommended when hematologic malignancies cannot be excluded.
Validation of an Immunoassay for Soluble Klotho Protein
Authors: Devaraj Sridevi , Syed Basir , Chien Alexander , Jialal Ishwarlal
Published: February 2012

The Klotho gene has been identified as an aging suppressor gene that encodes a transmembrane protein, which is expressed primarily in renal tubules. There are 2 forms of Klotho, membrane and secreted. However, there is a paucity of data on levels of soluble Klotho in diseases like diabetes and kidney disease. We validated an enzyme-linked immunosorbent assay for Klotho and quantitated Klotho levels separately in patients with diabetes and also in patients with chronic kidney disease (CKD).

The Klotho assay showed good precision and was linear down to 19 ng/mL. There were no significant effects on Klotho levels with the addition of common interferents such as ascorbate, triglycerides, or hemolysis; only bilirubin (250 mg/L) significantly reduced Klotho levels (P < .05). There was a significant reduction in Klotho levels in samples with glycated hemoglobin (HbA1c) levels of 6.5% or more compared with control samples (HbA1c < 6.5%; P < .001). We also documented significantly higher levels of Klotho with CKD. Thus, we validated an assay for Klotho and made the novel observation that levels are decreased in diabetes and increased in CKD.
Atypia of Undetermined Significance and Nondiagnostic Rates in The Bethesda System for Reporting Thyroid Cytopathology Are Inversely Related
Authors: VanderLaan Paul A. , Renshaw Andrew A. , Krane Jeffrey F.
Published: February 2012

There is substantial variation in the reported rates of different diagnostic categories in The Bethesda System for Reporting Thyroid Cytopathology (TBS). Specifically, the relationship between the nondiagnostic (ND) and atypia of undetermined significance (AUS) categories has not been closely examined previously. Data from published series in the literature and from 2 separate hospitals with more than 15,000 thyroid aspirates were reviewed. The AUS and ND rates were consistently negatively correlated when analyzed by year, aspirator, and cytologist. The strongest correlation was with cytologists (P < .0003). Absolute ND rates decreased by 1% for every 3.5% increase in AUS, implying the existence of a discrete population of cases that cytologists will classify as ND or AUS. As such, AUS and ND are not independent variables. Awareness of this relationship may be useful for laboratories and individual cytopathologists for refining the use of TBS.
An Evaluation of the Use of Oral Bisphosphonates and Risk of Esophageal Cancer
Authors: Haber Stacy L , McNatty Danny
Published: February 2012

Objective:

To evaluate the use of oral bisphosphonates and risk of esophageal cancer.

Data Sources:

MEDLINE (1948–October 2011) was searched using the terms esophageal cancer, esophageal carcinoma, bisphosphonate, bisphosphonates, etidronate, Pamidronate, alendronate, tiludronate, risedronate, zoledronic acid, and ibandronate. Citations from relevant publications were reviewed for additional information.

Study Selection and Data Extraction:

A comprehensive review of the available literature was performed.

Data Synthesis:

Two summaries of case reports and 3 observational studies were retrieved and reviewed. Oral bisphosphonates can cause esophageal irritation; therefore, it is biologically plausible that they may increase the risk of esophageal cancer. Although many cases were reported, causality was difficult to determine due to their weak methodology, and subsequent evaluations from national registers did not support an increased risk. Of the 3 observational studies (1 in patients with Barrett's esophagus and 2 using the same patient database), only 1 found an increased risk with use of daily or weekly regimens, and significant limitations were noted in each.

Conclusions:

Evidence on the use of bisphosphonates and risk of esophageal cancer is weak and conflicting. Additional studies are needed to further evaluate this issue and formulate stronger conclusions, in the meantime, health care professionals should ensure that patients take oral bisphosphonates properly to minimize esophageal irritation, are prescribed regimens that minimize exposure if adherence is difficult, and are evaluated for discontinuation of the drugs if appropriate. For patients at increased risk of esophageal cancer for other health reasons, nonoral bisphosphonates may be considered.
Estrogen-related receptor α regulates osteoblast differentiation via Wnt/β-catenin signaling
Authors: Auld Kathryn L , Berasi Stephen P , Liu Yan , Cain Michael , Zhang Ying , Huard Christine , Fukayama Shoichi , Zhang Jing , Choe Sung , Zhong Wenyan , Bhat Bheem M , Bhat Ramesh A , Brown Eugene L , Martinez Robert V
Published: February 2012

Based on its homology to the estrogen receptor and its roles in osteoblast and chondrocyte differentiation, the orphan nuclear receptor estrogen-related receptor α (ERRα (ESRRA)) is an intriguing therapeutic target for osteoporosis and other bone diseases. The objective of this study was to better characterize the molecular mechanisms by which ERRα modulates osteoblastogenesis. Experiments from multiple systems demonstrated that ERRα modulates Wnt signaling, a crucial pathway for proper regulation of bone development. This was validated using a Wnt-luciferase reporter, where ERRα showed co-activator-dependent (peroxisome proliferator-activated receptor gamma co-activator 1α, PGC-1α) stimulatory effects. Interestingly, knockdown ofERRαexpression also enhanced WNT signaling. In combination, these data indicated that ERRα could serve to either activate or repress Wnt signaling depending on the presence or absence of its co-activator PGC-1α. The observed Wnt pathway modulation was cell intrinsic and did not alter β-catenin nuclear translocation but was dependent on DNA binding of ERRα. We also found that expression of active ERRα correlated with Wnt pathway effects on osteoblastic differentiation in two cell types, consistent with a role for ERRα in modulating the Wnt pathway. In conclusion, this work identifies ERRα, in conjunction with co-activators such as PGC-1α, as a new regulator of the Wnt-signaling pathway during osteoblast differentiation, through a cell-intrinsic mechanism not affecting β-catenin nuclear translocation.
Kinetics of palladium particles on LiNbO3: an origin of the polarization-dependent catalysis
Authors: Kim Seungchul , Schoenberg Michael Rutenberg , Rappe Andrew M.
Published: February 2012

Using ab-initio calculations and kinetic Monte Carlo simulations, we demonstrate that the deposition geometries of palladium are strongly dependent on the polarization direction of the LiNbO3 substrate. Different stoichiometries and atomic structures of the positively and the negatively polarized substrates cause substantially different bonding configurations of palladium and energy barriers for the movement of Pd clusters. Our simulations predict that palladium atoms form bulky clusters on the positive surface, while they are deposited in a dispersed or planar manner on the negative surface at moderate temperature. We suggest that Inoue and coworkers’ observation [J. Phys. Chem.88, 1148 (1984)] that the catalytic activity of palladium depends on polarization direction of LiNbO3 substrate is, at least in part, due to differences in the geometric structures of palladium and the LiNbO3 surface.
The Vibrational Properties of Ultrananocrystalline Diamond Based on Molecular dynamics Simulations
Authors: Adiga Shashishekar P. , Adiga Vivekananda P. , Carpick Robert W. , Brenner Donald W.
Published: February 2012

We investigate the vibrational properties of ultrananocrystalline diamond (UNCD) using molecular dynamics simulations. We compare the vibrational spectra of two UNCD models of average grain size 2 and 4 nm with single crystal diamond and an isolated nanodiamond (ND) particle. The vibrational spectra of the ND particle and UNCD models exhibit the effect of phonon confinement as well as undercoordinated atoms at the surface/interfaces. This is further reflected in the specific heat of UNCD models and the ND particle that showed enhancements over that of single crystal diamond. The excess specific heat in UNCD models in comparison to single crystal diamond is found to be maximum at approximately 350 K.
Onset of size effects in lattice thermal conductivity and lifetime of low-frequency thermal phonons
Authors: Maznev A.A.
Published: February 2012

The onset of size effects in phonon-mediated thermal transport along a thin film at temperatures comparable or greater than the Debye temperature is analyzed theoretically. Assuming a quadratic frequency dependence of phonon relaxation rates in the low-frequency limit, a simple closed-form formula for the reduction of the in-plane thermal conductivity of thin films is derived. The effect scales as the square root of the film thickness, which leads to the prediction of measurable size-effects even at “macroscopic” distances ~100 μm. However, this prediction needs to be corrected to account for the deviation from the ω−2dependence of phonon lifetimes at sub-THz frequencies due to the transition from Landau-Rumer to Akhiezer mechanism of phonon dissipation.
Distribution of Additives in Single-Modified TiO2
Authors: Gleń Marta A. , Grzmil Barbara U.
Published: February 2012

In the present work the influence of different modifiers, calculated to B2O3, CeO2, Sb2O3, ZnO, and ZrO2, on their distribution in TiO2 is investigated. The phase composition and phase transformation of prepared rutile-TiO2 is determined by the selective leaching method, ICP-AES, XRD and FT-IR techniques. The addition of Sb2O3 to TiO2 has no influence on the anatase–rutile phase transformation, CeO2 and ZrO2 act as inhibitors of the TiO2 phase transformation and the addition of ZnO or B2O3 to TiO2 accelerates rutile formation. It is observed that boron is located in TiO2 in the form of soluble B2O3, zinc partly reacts with titanium forming co-phase TiZn2O4 and antimony addition to TiO2 presumably causing the formation of a co-phase of Sb with Ti. Cerium forms a separate phase, CeO2, and reacts partly with titanium, probably creating co-phase, CexTi(1-x)O2 (for example Ce0.8Ti0.2O2). Zirconium addition in TiO2 forms separate ZrO2 phase and solid solution of Zr with Ti.
Sheet moulding compounds with improved mechanical properties
Authors: Nicolau V. , Bertoneri N. , Scarello J. , Estenoz D.
Published: February 2012

This work studies the synthesis of styrene copolymers obtained from the reaction between isophthalic unsaturated polyester resins and styrene with the aim of improving the mechanical properties of sheet moulding compounds (SMC), specifically their flexibility and impact resistance.

The experimental work involves the experimental design; the SMC synthesis with different concentrations of 4 additives (methylmethacrylate; diethylenglycol, dioctilphthalate, and a commercial flexible resin); and the mechanical characterization including measurements of load-deflection curves; flexural strength (FS), flexural modulus (FM) and impact resistance (IR).
Steel-Magnesium Laminated Composites by Infiltration
Authors: Çetin Arda , Krebs Jérôme , Durussel Alexandre , Rossoll Andreas , Inoue Junya , Nambu Shoichi , Koseki Toshihiko , Mortensen Andreas
Published: February 2012

Steel–magnesium alloy laminated composites can be produced by gas-driven pressure infiltration of a molten magnesium alloy between layers of stacked steel sheets followed by directional solidification of the infiltrated magnesium alloy. A key step in the process is ensuring adequate separation and alignment of the steel sheets during the process; this is achieved by introducing small dimples in the steel sheets to hold them apart during infiltration. Advantages of the process are its speed, the defect-free composites it produces, and the fact that, unlike roll-bonded composites, the steel in the composite is in an annealed condition. The ultimate tensile strength of the as-cast laminates, of 260 MPa, obeys the rule of mixtures. The uniform tensile elongation, of around 20%, makes the infiltrated laminates nearly as ductile as the bulk steel it contains, implying that the magnesium alloy in the as-cast laminates has a substantially increased tensile ductility in comparison to the bulk state in a metallurgically equivalent condition.
Aspectos da ecologia reprodutiva de Pera glabrata (Schott) Poepp. ex Baill. (Euphorbiaceae) em uma área de Cerrado no estado de São Paulo
Authors: Freitas Juliana Ribeirão de , Figueiredo Rodolfo Antônio de , Nadai Igor Chiosini de , Hardman Lucas
Published: February 2012

Pera glabrata é uma árvore que apresenta ampla distribuição no Brasil. A espécie vegetal é de importância para a conservação e recuperação de áreas degradadas, pois está presente em áreas impactadas, produz e dispersa grande quantidade de sementes e constitui-se em fonte alimentar para elevado número de espécies animais. Apesar da importância fitossociológica da espécie, ainda não existem estudos que abordem a sua ecologia reprodutiva. Este trabalho teve como objetivo caracterizar aspectos da fenologia reprodutiva, da morfologia floral, dos sistemas reprodutivo e de polinização e da dispersão de sementes da espécie. O estudo foi realizado em uma área de Cerrado no município de São Carlos, SP. Verificou-se que Pera glabrata é dioica e apresenta floração massiva e as flores dos dois sexos são pequenas, involucradas, amarelas e de antese diurna. As flores masculinas apresentam néctar e emitem odor adocicado, e as femininas não oferecem recursos perceptíveis aos visitantes florais. As flores foram visitadas por 32 espécies de Diptera e Hymenoptera de pequeno porte. Ocorre a formação de frutos e sementes por autogamia. Foram identificadas 25 espécies de aves visitando indivíduos com frutos maduros, das quais 16 ingeriram as sementes ariladas. Pera glabrata é autogâmica, com síndrome de polinização por diversos pequenos insetos e com dispersão ornitocórica de suas sementes.
Diagnóstico quantitativo e qualitativo da arborização das praças de Aracaju, SE
Authors: Souza Anderson Linhares de , Ferreira Robério Anastácio , Mello Anabel Aparecida de , Plácido Débora da Rocha , Santos Carla Zoaid Alves dos , Graça Dalva Angélica Santos da , Almeida Júnior Pedro Paulo de , Barretto Soraia Stéfane Barbosa , Dantas Jolly Dayanne de Melo , Paula José Welton Azevedo de , Silva Thiago Lima da , Gomes Lucas Pedro Silva
Published: February 2012

Aracaju foi uma cidade planejada com simplicidade e rigor geométrico. Desde a sua fundação, ela vem passando por constantes alterações, havendo cada vez menos áreas verdes no ambiente urbano. A arborização urbana bem planejada é muito importante, pois as árvores trazem benefícios à cidade nos processos de ordens ecológica (clima e poluição), biológica (saúde física do homem) e psicológica (saúde mental do homem). Porém, a falta de planejamento dessa arborização e o uso inadequado de algumas espécies são empecilhos para se atingirem esses benefícios. Dessa forma, este trabalho foi realizado com o objetivo de avaliar a composição florística de 22 praças de Aracaju, SE, como forma de conhecer a atual situação de sua arborização e possibilitar intervenções para melhorar a adequação técnica do espaço verde urbano. O levantamento florístico foi realizado através de censo, no período de setembro de 2006 a julho de 2007, em cada praça, com o reconhecimento e identificação de todos os indivíduos arbóreos, utilizando-se as técnicas tradicionais de coleta e herborização. Realizou-se a identificação das espécies com o auxílio de literatura específica. Foram identificados 1.290 indivíduos, distribuídos em 20 famílias botânicas, 46 gêneros e 64 espécies, sendo nove espécies não identificadas. Das espécies identificadas, 58% são exóticas no território brasileiro e 42%, espécies nativas. As praças apresentam similaridade entre si, com coeficiente de Jaccard variando de 0,00 a 0,66, e a Praça Almirante Tamandaré e a Praça Graccho Cardoso foram as de maior similaridade (66%).
Eficiência técnica na indústria de base florestal brasileira via metas intermediárias
Authors: Santos Ricardo Bruno Nascimento dos
Published: February 2012

Propôs-se, neste artigo, uma busca de alvos, por etapas, com alvos intermediários nas camadas de isoeficiência para que o Setor de Fabricação de Produtos de Base Florestal (SFPBF) de cada Estado atinja, de forma gradual, nível de eficiência técnica mais elevado. Para isso, utilizaram-se dados da Pesquisa Industrial Anual (PIA) de 2007, do IBGE. Aplicou-se a Análise Envoltória de Dados (DEA) orientada ao insumo, tendo a receita líquida do setor como produto e como insumos o total do custo das operações industriais (COI) e as remunerações do setor (SRO). Dos 14 Estados analisados, o Espírito Santo foi o mais eficiente e o Rio de Janeiro, o mais ineficiente. Outros 12 Estados foram tecnicamente ineficientes, de forma que três devem, no curto prazo, buscar a camada 1, três a camada 2, dois a camada 3 e três a camada 4. Verificou-se que no Brasil o COI é a principal causa da ineficiência técnica.
Avaliação de um sistema de cavaqueamento de ponteiras de eucalipto para aproveitamento energético
Authors: Canto Juliana Lorensi do , Machado Carlos Cardoso , Seixas Fernando , Souza Amaury Paulo de , Sant' Anna Cleverson de Mello
Published: February 2012

Os objetivos deste trabalho foram avaliar o desempenho e estimar os custos de um sistema de cavaqueamento de ponteiras de eucalipto, resultantes de colheita florestal, para aproveitamento energético em uma empresa de base florestal localizada no Estado do Pará, na Região Norte do Brasil. O sistema era composto por um picador florestal, dois tratores florestais transportadores autocarregáveis (com grua) e uma carregadora frontal. A coleta de dados baseou-se em estudo de tempos e movimentos, determinação do consumo de combustível e pesagem dos cavacos produzidos. A produtividade média do sistema foi de 17,51 toneladas por hora efetiva. A eficiência operacional foi de 51,9%, devido a diversas demoras operacionais, principalmente para conserto e manutenção do picador. O transporte de cavacos foi considerado o ponto de estrangulamento do sistema, devido a ocorrências de falta de caminhão disponível no local para o carregamento. O sistema pode produzir entre 94 e 162 vezes mais energia do que consome. O custo do sistema por hora efetiva foi de R$376,56, o que representa R$21,51/t de cavacos ou R$2,70/GJ.
Avaliação do potencial do grits como material de construção na produção de tijolos de solo-cimento
Authors: Miranda Larissa de Almeida , Alvarenga Rita de Cássia Silva Sant' Anna , Pinto Junior Paulo Cesar Moreira , Paula Júnior Eduardo Dantas de , Carvalho Carlos Alexandre Braz de , Fassoni Délio Porto , Couto Lauro Gontijo
Published: February 2012

O "grits" é um resíduo sólido de características arenosas e coloração acinzentada, gerado pela indústria de polpa kraft durante a etapa de recuperação do licor branco empregado no cozimento dos cavacos de madeira. O objetivo deste trabalho foi estudar o potencial do grits como material de construção, considerando-se a sua empregabilidade na fabricação de tijolos de solo-cimento. Para a determinação da quantidade ideal de resíduo a ser utilizada, foram estudados os traços em volume 1:14:0; 1:10,5:3,5; 1:7:7; 1:3,5:10,5; e 1:0:14 de cimento, solo e grits, respectivamente. Os materiais foram caracterizados por meio de ensaios de análise granulométrica, limite de liquidez e limite de plasticidade, e os resultados foram de acordo com as prescrições normativas. O ensaio prático da caixa também foi usado para verificar os materiais, e os resultados atenderam às recomendações. Uma vez realizado o ensaio de compactação para obter o teor de umidade ótima, os tijolos foram produzidos com 90% desse valor, pois a resistência à compressão é favorecida com o material do ramo seco. No entanto, durante a moldagem não foi possível produzir tijolos com os traços 1:3,5:10,5 e 1:0:14, pois, nesses casos, as misturas de solo-cimento-grits não apresentaram plasticidade suficiente. Os tijolos produzidos com os demais traços foram, então, submetidos a ensaios de resistência à compressão e de absorção. Em relação à resistência à compressão, aos 28 dias todos os traços apresentaram valores médios superiores ao estabelecido pela normalização, que é de 2,0 MPa. Os tijolos fabricados com maior quantidade de grits apresentaram melhor desempenho no que se refere à resistência mecânica. Assim, este estudo não apenas apresenta o benefício ambiental de destinar corretamente o resíduo, como também contribui com novos materiais para a construção civil.
Controle alternativo de helmintos de Astyanax cf. zonatus utilizando fitoterapia com sementes de abóbora (Cucurbita maxima) e mamão (Carica papaya)
Authors: Fujimoto Rodrigo Y. , Costa Helrik C. da , Ramos Fabrício M.
Published: February 2012

O objetivo do trabalho foi avaliar a eficácia de sementes de abóbora e mamão desidratadas e moídas, no controle de helmintos parasitos de Astyanax cf. zonatus. Sessenta peixes foram distribuídos em doze recipientes, um peixe/litro. O experimento constituiu de quatro tratamentos e três repetições: TJ = peixes deixados em jejum; TRC = peixes alimentados com ração comercial; TSA = peixes alimentados ad libitum com abóbora, e TSM = peixes alimentados ad libitum com mamão. Após sete dias de alimentação, todos os peixes foram pesados, e o sangue foi retirado para extensão sanguínea. A eficácia foi determinada, verificando a presença de parasitos nas brânquias, no estômago e no intestino. Os peixes do TJ e TSM apresentaram perda de peso (39% e 25%, respectivamente). O TSA apresentou melhor eficácia no controle de nematóides do intestino e do estômago (95,26% e 92,48%). No controle de monogenéticos TSM promoveu 72% de eficácia. Na hematologia observou-se aumento de monócitos nos peixes do TSM e os valores de eosinofilos diminuíram nos tratamentos TSA, TSM e TRC. Assim pode-se concluir que a alimentação com abóbora pode ser utilizado como um controle alternativo eficaz de nematóides intestinais do lambari.
Vacina experimental produzida em cultivo celular confere proteção parcial contra o ectima contagioso em ovinos
Authors: Schmidt Candice , Cargnelutti Juliana Felipetto , Martins Mathias , Weiblen Rudi , Flores Eduardo Furtado
Published: February 2012

O ectima contagioso (também conhecido como orf), é uma doença debilitante de ovinos e caprinos causada pelo vírus do orf (ORFV). A vacinação tem sido usada com relativo sucesso no controle da doença. No entanto, as vacinas atuais contêm amostras virulentas do agente, são produzidas por escarificação cutânea de animais, e apresentam eficácia questionável. Assim, o presente trabalho teve como objetivo produzir e testar a eficácia de uma vacina experimental produzida em cultivo celular. A cepa IA-82 do ORFV foi submetida a 21 passagens em cultivo de células BHK-21 e usada para vacinar ovinos jovens (n=30), por escarificação cutânea na face interna da coxa. A vacinação produziu pústulas e crostas em 16 dos 30 ovinos vacinados, indicando imunização adequada. Noventa dias após a vacinação, ovinos vacinados (n=16) e controles (n=16) foram inoculados com uma cepa virulenta do ORFV (10(6,9)DICC50/mL) após escarificação na comissura labial. Todos os animais desenvolveram lesões típicas de ectima, incluindo hiperemia, vesículas, pústulas e crostas. No entanto, os animais vacinados desenvolveram lesões mais leves e passageiras do que os controles, e os escores clínicos foram estatisticamente diferentes (p<0,05) entre os dias 10 e 22 pós-desafio. Além disso, o tempo de duração da doença foi significativamente inferior (p<0,05) nos animais vacinados. Os animais vacinados também excretaram menor quantidade de vírus (p<0,05) e por um período significativamente mais curto do que os controles (13 dias versus 22 dias, p<0,001). Esses resultados demonstram a proteção parcial conferida pela vacina experimental e, dependendo da melhoria dos índices de imunização e proteção, são promissores no sentido da utilização de vacinas contra o ORFV produzidas em cultivo celular.
Avaliação microbiológica, histológica e imunológica de frangos de corte desafiados com Salmonella Enteritidis e Minnesota e tratados com ácidos orgânicos
Authors: Pickler Larissa , Hayashi Ricardo M. , Lourenço Mariana C. , Miglino Leonardo B. , Caron Luiz Felipe , Beirão Breno C.B. , Silva Ana V.F. , Santin Elizabeth
Published: February 2012

Dois experimentos foram desenvolvidos para avaliar a eficiência de ácidos orgânicos frente a Salmonella enterica enterica sorovar Enteritidis (SE) e Minnesota (SM) em frangos. No primeiro experimento foram avaliados 3 tratamentos: T1 - ração adicionada de ácido orgânico, T2 - ração adicionada de ácido orgânico e ácido orgânico na água de bebida, T3 - grupo controle. Todos os animais foram inoculados com SE, via oral. A utilização de ácidos orgânicos na ração (T1) e na ração e na água (T2) diminuíram a excreção de Salmonella no papo e no ceco 7 dias pós inoculação com SE e houve redução de células CD3+ no jejuno dos frangos. No segundo experimento foram avaliados 4 tratamentos sendo T1 - controle, T2 - controle inoculado via oral com Salmonella Minnesota (SM), T3 - animais inoculados via oral com SM e ácidos orgânicos na ração e T4 - animais inoculados via oral com SM e ácidos orgânicos na ração e na água de bebida. Ácidos orgânicos a ração (T3) e na ração e na água (T4) reduziram a excreção de SM em papo de frangos de corte desafiados, 7 dias após inoculação. O uso de ácidos orgânicos na ração e na ração e na água foram mais eficientes em reduzir SE do que SM.