bluuebunny/crossref_metadata_2025 huggingface dataset:
Stem cell therapy for idiopathic pulmonary fibrosis: a protocol proposal
Authors: Tzouvelekis Argyris , Koliakos George , Ntolios Paschalis , Baira Irene , Bouros Evangelos , Oikonomou Anastasia , Zissimopoulos Athanassios , Kolios George , Kakagia Despoina , Paspaliaris Vassilis , Kotsianidis Ioannis , Froudarakis Marios , Bouros Demosthenes
Published: November 2011

Background

Idiopathic pulmonary fibrosis represents a lethal form of progressive fibrotic lung disorder with gradually increasing incidence worldwide. Despite intense research efforts its pathogenesis is still elusive and controversial reflecting in the current disappointing status regarding its treatment. Patients and Methods: We report the first protocol proposal of a prospective, unicentric, non-randomized, phase Ib clinical trial to study the safety and tolerability of the adipose-derived stem cells (ADSCs) stromal vascular fraction (SVF) as a therapeutic agent in IPF. After careful patient selection based on functional criteria (forced vital capacity-FVC > 50%, diffuse lung capacity for carbon monoxide-DLCO > 35% of the predicted values) all eligible subjects will be subjected to lipoaspiration resulting in the isolation of approximately 100- 500 gr of adipose tissue. After preparation, isolation and labelling ADSCs-SVF will be endobronchially infused to both lower lobes of the fibrotic lungs. Procedure will be repeated thrice at monthly intervals. Primary end-point represent safety and tolerability data, while exploratory secondary end-points include assessment of clinical functional and radiological status. Results: Preliminary results recently presented in the form of an abstract seem promising and tantalizing since there were no cases of clinically significant allergic reactions, infections, disease acute exacerbations or ectopic tissue formation. In addition 6 months follow-up data revealed a marginal improvement at 6-minute walking distance and forced vital capacity.

Conclusions

Adipose tissue represents an abundant, safe, ethically uncontested and potentially beneficial source of stem cells for patients with IPF. Larger multicenter phase II and III placebo-controlled clinical trials are sorely needed in order to prove efficacy. However, pilot safety studies are of major importance and represent the first hamper that should be overcome to establish a rigid basis for larger clinical trials.
Molecular evolution of the H6 subtype influenza a viruses from poultry in eastern China from 2002 to 2010
Authors: Zhao Guo , Lu Xinlun , Gu Xiaobing , Zhao Kunkun , Song Qingqing , Pan Jinjin , Xu Quangang , Duan Zhiqiang , Peng Daxin , Hu Shunlin , Wang Xiaoquan , Liu Xiufan
Published: November 2011

Background

Although extensive data demonstrates that the majority of H6 duck isolates belonged to a single H6N2 virus lineage with a single gene constellation in southern China from 2000 to 2005, the prevalence of H6N2 virus in poultry in Eastern China is largely unknown.

Results

Epidemiology revealed that H6N2 viruses were the most frequently detected influenza subtypes in live bird markets from 2002 to 2008 in Eastern China, but from 2009 onwards, they were replaced with novel H6N6 viruses. We phylogenetically and antigenically analyzed 42 H6 viruses isolated mainly in domestic ducks from 2002 to 2010 in Eastern China. Surprisingly, none of these isolates grouped with the previously described H6N2 viruses which belonged to a single H6N2 virus lineage with a single gene constellation in domestic ducks in southern China from 2000 to 2005. Two distinct hemagglutinin lineages were identified and they all underwent frequent reassortment with multiple virus subtypes from the natural gene pool, but few reassortants were persistent or prevalent.

Conclusions

Five subtypes of H6 influenza viruses (H6N1, H6N2, H6N5, H6N6 and H6N8) cocirculated in Eastern China, which form a significant part of the natural influenza virus reservoir in domestic ducks, and significant viral reassortment is still ongoing in this species.
Isolation and molecular characterization of genotype 1 Japanese encephalitis virus, SX09S-01, from pigs in China
Authors: Cao Qi S , Li Xiang M , Zhu Qiao Y , Wang Dan D , Chen Huan C , Qian Ping
Published: November 2011

Background

Pigs play a critical role in Japanese encephalitis virus (JEV) transmission between mosquitos and humans. In 2009, lots of piglets developed symptom of viral encephalitis in a pig farm in Yunchen, Shanxi province.

Methods

Virus isolation was carried out in BHK-21 cells. Immunohistochemistry, RT-PCR and indirect immunofluorescent assay were used to identify the newly isolated virus. The complete genome of one isolate (SX09S-01 strain) was sequenced and analyzed. Two phylogenetic trees were constructed on the basis of the 24 full-length JEV genomes and 62 E genes mostly selected from China.

Results

JEV SX09S-01 strain was isolated from piglets. Sequence analysis indicates that the completed genome sequences of this strain consists of 10965 nucleotides and there are 13 nucleotides deletion in the 3' nontranslated variable region. Compared with other JEV strains, homology ranges from 99.1% (XJ69) to 74.1% (XZ0934) and 99.6% (XJ69) to 91.1% (XZ0934) on the level of nucleotide and amino acid sequences, respectively. Phylogenetic trees show that SX09S-01 strain belongs to genotype I and it is most closely related to the XJ69 strain.

Conclusions

Genotype I of JEV still circulates in Yuncheng and it is thus important for active surveillance on genotype I of JEV from the swine population.
Comparative study on saponin fractions from Panax notoginseng inhibiting inflammation-induced endothelial adhesion molecule expression and monocyte adhesion
Authors: Wang Nan , Wan Jian-Bo , Chan Shun-Wan , Deng Yan-Hui , Yu Nan , Zhang Qing-Wen , Wang Yi-Tao , Lee Simon Ming-Yuen
Published: November 2011

Background

Panax notoginsengis commonly used for the treatment of cardiovascular diseases in China. The present study investigates the effects of three different saponin fractions (ietotal saponins, PNS; protopanaxadiol-type saponin, PDS; and protopanaxatriol-type saponin, PTS) and two major individual ingredients (ieginsenoside Rg1and Rb1) fromP. notoginsengon the endothelial inflammatory responsein vitroandin vivo.

Methods

Recombinant human tumor necrosis factor-α (TNF-α) was added to the culture medium of human coronary artery endothelial cells (HCAECs) to induce an inflammatory response. A cell adhesion assay was used to determine the effect of theP. notoginsengsaponin fractions on endothelial-monocyte interaction. The cell adhesion molecule (CAMs) expression, including ICAM-1 and VCAM-1, in the protein level on the surface of endothelial cells were measured by cellular ELISA. CAMs expression in mRNA level was also assayed by qRT-PCR in the HCAECs and the aorta of rat fed with high cholesterol diet (HCD). Western blotting was used to detect effect of the saponin fractions on CAMs protein expression in HCAECs. In addition, nuclear translocation of p65, a surrogate marker for NF-κB activation, was measured by immunostaining.

Results

Three saponin fractions and two individual ginsenosides exhibited the inhibitory effects on monocyte adhesion on TNF-α-activated HCAECs and expression of ICAM-1 and VCAM-1 at both mRNA and protein levelsin vitro. The saponin fractions exhibited a similar trend of the inhibitory effects on the mRNA expression of CAMs in the aorta of HCD-fed ratin vivo. These inhibitory effect of saponin fractions maybe attribute partially to the suppression of the TNF-α-induced NF-κB activation.

Conclusion

Our data demonstrate that saponin fractions (iePNS, PDS and PTS) and major individual ginsenosides (ieRg1and Rb1) have potential anti-atherogenic effects. Among the tested saponin fractions, PDS is the most potent saponin fraction against TNF-α-induced monocyte adhesion as well as the expression of adhesion moleculesin vitroandin vivo.
Some aspects of purinergic signaling in the ventricular system of porcine brain
Authors: Czarnecka Joanna , Roszek Katarzyna , Jabłoński Artur , Smoliński Dariusz Jan , Komoszyński Michał
Published: November 2011

Background

Numerous signaling pathways function in the brain ventricular system, including the most important - GABAergic, glutaminergic and dopaminergic signaling. Purinergic signalization system - comprising nucleotide receptors, nucleotidases, ATP and adenosine and their degradation products - are also present in the brain. However, the precise role of nucleotide signalling pathway in the ventricular system has been not elucidated so far. The aim of our research was the identification of all three elements of purinergic signaling pathway in the porcine brain ventricular system.

Results

Besides nucleotide receptors on the ependymocytes surface, we studied purines and pyrimidines in the CSF, including mechanisms of nucleotide signaling in the swine model (Sus scrofa domestica). The results indicate presence of G proteins coupled P2Y receptors on ependymocytes and also P2X receptors engaged in fast signal transmission. Additionally we found in CSF nucleotides and adenosine in the concentration sufficient to P receptors activation. These extracellular nucleotides are metabolised by adenylate kinase and nucleotidases from at least two families: NTPDases and NPPases. A low activity of these nucleotide metabolising enzymes maintains nucleotides concentration in ventricular system in micromolar range. ATP is degraded into adenosine and inosine.

Conclusions

Our results confirm the thesis about cross-talking between brain and ventricular system functioning in physiological as well as pathological conditions. The close interaction of brain and ventricular system may elicit changes in qualitative and quantitative composition of purines and pyrimidines in CSF. These changes can be dependent on the physiological state of brain, including pathological processes in CNS.
Genes2WordCloud: a quick way to identify biological themes from gene lists and free text
Authors: Baroukh Caroline , Jenkins Sherry L , Dannenfelser Ruth , Ma'ayan Avi
Published: November 2011

Background

Word-clouds recently emerged on the web as a solution for quickly summarizing text by maximizing the display of most relevant terms about a specific topic in the minimum amount of space. As biologists are faced with the daunting amount of new research data commonly presented in textual formats, word-clouds can be used to summarize and represent biological and/or biomedical content for various applications.

Results

Genes2WordCloud is a web application that enables users to quickly identify biological themes from gene lists and research relevant text by constructing and displaying word-clouds. It provides users with several different options and ideas for the sources that can be used to generate a word-cloud. Different options for rendering and coloring the word-clouds give users the flexibility to quickly generate customized word-clouds of their choice.

Methods

Genes2WordCloud is a word-cloud generator and a word-cloud viewer that is based on WordCram implemented using Java, Processing, AJAX, mySQL, and PHP. Text is fetched from several sources and then processed to extract the most relevant terms with their computed weights based on word frequencies. Genes2WordCloud is freely available for use online; it is open source software and is available for installation on any web-site along with supporting documentation at http://www.maayanlab.net/G2W.

Conclusions

Genes2WordCloud provides a useful way to summarize and visualize large amounts of textual biological data or to find biological themes from several different sources. The open source availability of the software enables users to implement customized word-clouds on their own web-sites and desktop applications.
Decreased levels of serum glutathione peroxidase 3 are associated with papillary serous ovarian cancer and disease progression
Authors: Agnani Deep , Camacho-Vanegas Olga , Camacho Catalina , Lele Shashi , Odunsi Kunle , Cohen Samantha , Dottino Peter , Martignetti John A
Published: November 2011

Background

Glutathione peroxidase 3 (GPX3) is a selenocysteine-containing antioxidant enzyme that reacts with hydrogen peroxide and soluble fatty acid hydroperoxides, thereby helping to maintain redox balance within cells. Serum levels of GPX3 have been found to be reduced in various cancers including prostrate, thyroid, colorectal, breast and gastric cancers. Intriguingly, GPX3 has been reported to be upregulated in clear cell ovarian cancer tissues and thus may have implications in chemotherapeutic resistance. Since clear cell and serous subtypes of ovarian cancer represent two distinct disease entities, the aim of this study was to determine GPX3 levels in serous ovarian cancer patients and establish its potential as a biomarker for detection and/or surveillance of papillary serous ovarian cancer, the most frequent form of ovarian tumors in women.

Patients and Methods

Serum was obtained from 66 patients (median age: 62 years, range: 22-89) prior to surgery and 65 controls with a comparable age-range (median age: 53 years, range: 25-83). ELISA was used to determine the levels of serum GPX3. The Mann Whitney U test was performed to determine statistical significance between the levels of serum GPX3 in patients and controls.

Results

Serum levels of GPX3 were found to be significantly lower in patients than controls (p = 1 × 10-2). Furthermore, this was found to be dependent on the stage of disease. While levels in early stage (I/II) patients showed no significant difference when compared to controls, there was a significant reduction in late stage (III/IV, p = 9 × 10-4) and recurrent (p = 1 × 10-2) patients. There was a statistically significant reduction in levels of GPX3 between early and late stage (p = 5 × 10-4) as well as early and recurrent (p = 1 × 10-2) patients. Comparison of women and controls stratified to include only women at or above 50 years of age shows that the same trends were maintained and the differences became more statistically significant.

Conclusions

Serum GPX3 levels are decreased in women with papillary serous ovarian cancer in a stage-dependent manner and also decreased in women with disease recurrence. Whether this decrease represents a general feature in response to the disease or a link to the progression of the cancer is unknown. Understanding this relationship may have clinical and therapeutic consequences for women with papillary serous adenocarcinoma.
Aeromagnetic anomalies over faulted strata
Authors: Grauch V. J. S. , Hudson Mark R.
Published: November 2011

High-resolution aeromagnetic surveys are now an industry standard and they commonly detect anomalies that are attributed to faults within sedimentary basins. However, detailed studies identifying geologic sources of magnetic anomalies in sedimentary environments are rare in the literature. Opportunities to study these sources have come from well-exposed sedimentary basins of the Rio Grande rift in New Mexico and Colorado. High-resolution aeromagnetic data from these areas reveal numerous, curvilinear, low-amplitude (2–15 nT at 100-m terrain clearance) anomalies that consistently correspond to intrasedimentary normal faults (Figure 1). Detailed geophysical and rock-property studies provide evidence for the magnetic sources at several exposures of these faults in the central Rio Grande rift (summarized in Grauch and Hudson, 2007, and Hudson et al., 2008). A key result is that the aeromagnetic anomalies arise from the juxtaposition of magnetically differing strata at the faults as opposed to chemical processes acting at the fault zone. The studies also provide (1) guidelines for understanding and estimating the geophysical parameters controlling aeromagnetic anomalies at faulted strata (Grauch and Hudson), and (2) observations on key geologic factors that are favorable for developing similar sedimentary sources of aeromagnetic anomalies elsewhere (Hudson et al.).
Application of a grid-consistent inversion to a 4D reservoir model
Authors: Thore Pierre
Published: November 2011

Extraction of the 4D signal from time-lapse seismic is an efficient way to evaluate the lateral evolution of changes in fluid pressure and saturation during hydrocarbon production. This 4D seismic signal can be used in two ways (Castro et al., 2009): qualitatively (from a static perspective), thus evaluating whether a compartment has been drained or not, or if a fault is permeable or not; or quantitatively (from a dynamic perspective) by trying to exactly match changes in dynamic properties predicted from fluid-flow simulation with 4D seismic signal itself. In both approaches, the main difficulty is to link the seismic information with a description of the reservoir grid, especially with regard to scaling problems. Relative to the simulation model, the 4D seismic signal is obtained with a higher lateral resolution (12.5 or 25 m) and a poorer vertical resolution (10–20 m). Indeed, the reservoir grid consists of a set of layers with a very high vertical resolution (1–5 m) and limited lateral resolution (50–100 m). Here, we present a novel approach which aims to solve these problems by estimating the 4D seismic signal at (almost) reservoir grid scale. We demonstrate this by application to an oil-producing field in West Africa to finally derive a complete workflow for history matching the reservoir model using the 4D seismic signal.
Inferring in-situ stress changes by statistical analysis of microseismic event characteristics
Authors: Grob Melanie , van der Baan Mirko
Published: November 2011

Two commonly estimated fractal dimensions, called b and D values, represent statistical characteristics in the distribution of magnitude sizes (b) and spatial hypocenter locations (D) of microseismic events, respectively. We establish that the values of these two dimensions are related to specific stress regimes. Through the case study of a heavy-oil field drained using cyclic steam stimulation, we infer that the measured temporal variation in fractal dimension b is most likely due to significant changes in the local stress regime over a seven-month period, ranging from extensional faulting (fractures opening), via a strike-slip regime, to finally compressive faulting (fractures closing). The fracture dimension D indicates predominantly planar-to-spherical hypocenter spatial distributions in the first and last stages, but changes to a more linear-to-planar spatial pattern in the intermediate strike-slip regime when the vertical stress is anticipated to be in between the maximum and minimum horizontal stresses. These changes could be due to localized pore-fluid overpressure. A statistical analysis of the microseismic event locations and their magnitudes is therefore a useful method to understand reservoir geomechanics and thereby facilitate its management.
Role of IGFBP-3 in the Regulation of β-Cell Mass during Obesity: Adipose Tissue/β-Cell Cross Talk
Authors: Palau Nuria , Rebuffat Sandra A. , Altirriba Jordi , Piquer Sandra , Hanzu Felicia A. , Gomis Ramon , Barbera Albert
Published: November 2011

In obesity an increase in β-cell mass occurs to cope with the rise in insulin demand. This β-cell plasticity is essential to avoid the onset of hyperglycemia, although the molecular mechanisms that regulate this process remain unclear. This study analyzed the role of adipose tissue in the control of β-cell replication. Using a diet-induced model of obesity, we obtained conditioned media from three different white adipose tissue depots. Only in the adipose tissue depot surrounding the pancreas did the diet induce changes that led to an increase in INS1E cells and the islet replication rate. To identify the factors responsible for this proliferative effect, adipose tissue gene expression analysis was conducted by microarrays and quantitative RT-PCR. Of all the differentially expressed proteins, only the secreted ones were studied. IGF binding protein 3 (Igfbp3) was identified as the candidate for this effect. Furthermore, in the conditioned media, although the blockage of IGFBP3 led to an increase in the proliferation rate, the blockage of IGF-I receptor decreased it. Taken together, these data show that obesity induces specific changes in the expression profile of the adipose tissue depot surrounding the pancreas, leading to a decrease in IGFBP3 secretion. This decrease acts in a paracrine manner, stimulating the β-cell proliferation rate, probably through an IGF-I-dependent mechanism. This cross talk between the visceral-pancreatic adipose tissue and β-cells is a novel mechanism that participates in the control of β-cell plasticity.
TGF-β Mediates Suppression of Adipogenesis by Estradiol through Connective Tissue Growth Factor Induction
Authors: Kumar Ashok , Ruan Ming , Clifton Kari , Syed Farhan , Khosla Sundeep , Oursler Merry Jo
Published: November 2011

In the bone marrow cavity, adipocyte numbers increase, whereas osteoblast progenitor numbers decrease with aging. Because adipocytes and osteoblasts share a common progenitor, it is possible that this shift is due to an increase in adipocyte-lineage cells at the expense of osteoblast-lineage commitment. Estrogens inhibit adipocyte differentiation, and in both men and women, circulating estrogens correlate with bone loss with aging. In bone cells, estrogens stimulate expression of TGF-β and suppress mesenchymal cell adipogenesis. Using a tripotential mesenchymal cell line, we have examined whether estradiol suppression of adipocyte differentiation is due to stimulation of TGF-β and the mechanism by which TGF-β suppresses adipogenesis. We observed that estradiol-mediated suppression of adipogenic gene expression required at least 48 h treatment. TGF-β expression increased within 24 h of estradiol treatment, and TGF-β inhibition reversed estradiol influences on adipogenesis and adipocyte gene expression. Connective tissue growth factor (CTGF) mediates TGF-β suppression of adipogenesis in mouse 3T3-L1 cells. CTGF expression was induced within 24 h of TGF-β treatment, whereas estradiol-mediated induction required 48 h treatment. Moreover, estradiol-mediated induction of CTGF was abrogated by TGF-β inhibition. These data support that estradiol effects on adipogenesis involves TGF-β induction, which then induces CTGF to suppress adipogenesis.
Mutual Regulation of Growth Hormone and Bone Morphogenetic Protein System in Steroidogenesis by Rat Granulosa Cells
Authors: Nakamura Eri , Otsuka Fumio , Inagaki Kenichi , Miyoshi Tomoko , Matsumoto Yoshinori , Ogura Kanako , Tsukamoto Naoko , Takeda Masaya , Makino Hirofumi
Published: November 2011

GH induces preantral follicle growth and differentiation with oocyte maturation. However, the effects of GH on ovarian steroidogenesis and the mechanisms underlying its effects have yet to be elucidated. In this study, we investigated the actions of GH on steroidogenesis by rat granulosa cells isolated from early antral follicles by focusing on the ovarian bone morphogenetic protein (BMP) system. We found that GH suppressed FSH-induced estradiol production with reduction in aromatase expression and, in contrast, GH increased FSH-induced progesterone level with induction of steroidogenic acute regulatory protein, side chain cleavage cytochrome P450, and 3β-hydroxysteroid dehydrogenase. The effects of GH on steroidogenesis by granulosa cells were enhanced in the presence of the BMP antagonist noggin. Coculture of GH with oocytes did not alter GH regulation of steroidogenesis. Steroid production induced by cAMP donors was not affected by GH treatment and the GH effects on FSH-induced steroid production were not accompanied by changes in cAMP synthesis, suggesting that GH actions were not directly mediated by the cAMP-protein kinase A pathway. GH exerted synergistic effects on MAPK activation elicited by FSH, which regulated FSH-induced steroidogenesis. In addition, GH-induced signal transducer and activator of transcription phosphorylation was involved in the induction of IGF-I expression. GH increased IGF-I, IGF-I receptor, and FSH receptor expression in granulosa cells, and inhibition of IGF-I signaling restored GH stimulation of FSH-induced progesterone production, suggesting that endogenous IGF-I is functionally involved in GH effects on progesterone induction. BMP inhibited IGF-I effects that increased FSH-induced estradiol production with suppression of expression of the GH/IGF-I system, whereas GH/IGF-I actions impaired BMP-Sma and Mad related protein 1/5/8 signaling through down-regulation of the expression of BMP receptors. Thus, GH acts to modulate estrogen and progesterone production differentially through endogenous IGF-I activity in granulosa cells, in which GH-IGF-I interaction leads to antagonization of BMP actions including suppression of FSH-induced progesterone production. Mutual balance between GH/IGF-I and BMP signal intensities may be a key for regulating gonadotropin-induced steroidogenesis in growing follicles.
Rapid contrast gain reduction following motion adaptation
Authors: Nordström Karin , de Miguel Irene Moyer , O'Carroll David C.
Published: November 2011

Neural and sensory systems adapt to prolonged stimulation to allow signaling across broader input ranges than otherwise possible with the limited bandwidth of single neurons and receptors. In the visual system, adaptation takes place at every stage of processing, from the photoreceptors that adapt to prevailing luminance conditions, to higher-order motion-sensitive neurons that adapt to prolonged exposure to motion. Recent experiments using dynamic, fluctuating visual stimuli indicate that adaptation operates on a time scale similar to that of the response itself. Further work from our own laboratory has highlighted the role for rapid motion adaptation in reliable encoding of natural image motion. Physiologically, motion adaptation can be broken down into four separate components. It is not clear from the previous studies which of these motion adaptation components are involved in the fast and dynamic response changes. To investigate the adapted response in more detail, we therefore analyzed the effect of motion adaptation using a test–adapt–test protocol with adapting durations ranging from 20 ms to 20 s. Our results underscore the very rapid rate of motion adaptation, suggesting that under free flight, visual motion-sensitive neurons continuously adapt to the changing scenery. This might help explain recent observations of strong invariance in the response to natural scenes with highly variable contrast and image structure.
Divergent transcriptomic responses to repeated and single cold exposures in Drosophila melanogaster
Authors: Zhang Jian , Marshall Katie E. , Westwood J. Timothy , Clark Melody S. , Sinclair Brent J.
Published: November 2011

Insects in the field are exposed to multiple bouts of cold, and there is increasing evidence that the fitness consequences of repeated cold exposure differ from the impacts of a single cold exposure. We tested the hypothesis that different kinds of cold exposure (in this case, single short, prolonged and repeated cold exposure) would result in differential gene expression. We exposed 3 day old adult female wild-type Drosophila melanogaster (Diptera: Drosophilidae) to –0.5°C for a single 2 h exposure, a single 10 h exposure, or five 2 h exposures on consecutive days, and extracted RNA after 6 h of recovery. Global gene expression was quantified using an oligonucleotide microarray and validated with real-time PCR using different biological replicates. We identified 76 genes upregulated in response to multiple cold exposure, 69 in response to prolonged cold exposure and 20 genes upregulated in response to a single short cold exposure, with a small amount of overlap between treatments. Three genes – Turandot A, Hephaestus and CG11374 – were upregulated in response to all three cold exposure treatments. Key functional groups upregulated include genes associated with muscle structure and function, the immune response, stress response, carbohydrate metabolism and egg production. We conclude that cold exposure has wide-ranging effects on gene expression in D. melanogaster and that increased duration or frequency of cold exposure has impacts different to those of a single short cold exposure. This has important implications for extrapolating laboratory studies of insect overwintering that are based on only a single cold exposure.
Hydrogen sulfide (H2S) and hypoxia inhibit salmonid gastrointestinal motility: evidence for H2S as an oxygen sensor
Authors: Dombkowski Ryan A. , Naylor Marie G. , Shoemaker Emma , Smith Michelle , DeLeon Eric R. , Stoy Gilbrian F. , Gao Yan , Olson Kenneth R.
Published: November 2011

Hydrogen sulfide (H2S) has been shown to affect gastrointestinal (GI) motility and signaling in mammals and O2-dependent H2S metabolism has been proposed to serve as an O2 ‘sensor’ that couples hypoxic stimuli to effector responses in a variety of other O2-sensing tissues. The low PO2 values and high H2S concentrations routinely encountered in the GI tract suggest that H2S might also be involved in hypoxic responses in these tissues. In the present study we examined the effect of H2S on stomach, esophagus, gallbladder and intestinal motility in the rainbow trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch) and we evaluated the potential for H2S in oxygen sensing by examining GI responses to hypoxia in the presence of known inhibitors of H2S biosynthesis and by adding the sulfide donor cysteine (Cys). We also measured H2S production by intestinal tissue in real time and in the presence and absence of oxygen. In tissues exhibiting spontaneous contractions, H2S inhibited contraction magnitude (area under the curve and amplitude) and frequency, and in all tissues it reduced baseline tension in a concentration-dependent relationship. Longitudinal intestinal smooth muscle was significantly more sensitive to H2S than other tissues, exhibiting significant inhibitory responses at 1–10 μmol l–1 H2S. The effects of hypoxia were essentially identical to those of H2S in longitudinal and circular intestinal smooth muscle; of special note was a unique transient stimulatory effect upon application of both hypoxia and H2S. Inhibitors of enzymes implicated in H2S biosynthesis (cystathionine β-synthase and cystathionine γ-lyase) partially inhibited the effects of hypoxia whereas the hypoxic effects were augmented by the sulfide donor Cys. Furthermore, tissue production of H2S was inversely related to O2; addition of Cys to intestinal tissue homogenate stimulated H2S production when the tissue was gassed with 100% nitrogen (∼0% O2), whereas addition of oxygen (∼10% O2) reversed this to net H2S consumption. This study shows that the inhibitory effects of H2S on the GI tract of a non-mammalian vertebrate are identical to those reported in mammals and they provide further evidence that H2S is a key mediator of the hypoxic response in a variety of O2-sensitive tissues.
Black wildebeest skeletal muscle exhibits high oxidative capacity and a high proportion of type IIx fibres
Authors: Kohn Tertius Abraham , Curry Jennifer Wendy , Noakes Timothy David
Published: November 2011

The aim of the study was to investigate the skeletal muscle characteristics of black wildebeest (Connochaetes gnou) in terms of fibre type and metabolism. Samples were obtained post mortem from the vastus lateralis and longissimus lumborum muscles and analysed for myosin heavy chain (MHC) content. Citrate synthase (CS), 3-hydroxyacyl co A dehydrogenase (3HAD), phosphofructokinase (PFK), lactate dehydrogenase (LDH) and creatine kinase (CK) activities were measured spectrophotometrically to represent the major metabolic pathways in these muscles. Both muscles had less than 20% MHC I, whereas MHC IIa and MHC IIx were expressed in excess of 50% in the vastus lateralis and longissimus lumborum muscles, respectively. Overall fibre size was 2675±1034 μm2, which is small compared with other species. Oxidative capacity (CS and 3HAD) in both muscles was high and did not differ from one another, but the longissimus lumborum had significantly (P<0.05) higher PFK, LDH and CK activities. No relationships were observed between fibre type and the oxidative and oxygen-independent metabolic capacity as measured by specific enzyme activities. This study confirms the presence of both fast-twitch fibres and high oxidative capacity in black wildebeest, indicating an animal that can run very fast but is also fatigue resistant.
Locomotor activity during the frenzy swim: analysing early swimming behaviour in hatchling sea turtles
Authors: Pereira Carla M. , Booth David T. , Limpus Colin J.
Published: November 2011

Swimming effort of hatchling sea turtles varies across species. In this study we analysed how swim thrust is produced in terms of power stroke rate, mean maximum thrust per power stroke and percentage of time spent power stroking throughout the first 18 h of swimming after entering the water, in both loggerhead and flatback turtle hatchlings and compared this with previous data from green turtle hatchlings. Loggerhead and green turtle hatchlings had similar power stroke rates and percentage of time spent power stroking throughout the trial, although mean maximum thrust was always significantly higher in green hatchlings, making them the most vigorous swimmers in our three-species comparison. Flatback hatchlings, however, were different from the other two species, with overall lower values in all three swimming variables. Their swimming effort dropped significantly during the first 2 h and kept decreasing significantly until the end of the trial at 18 h. These results support the hypothesis that ecological factors mould the swimming behaviour of hatchling sea turtles, with predator pressure being important in determining the strategy used to swim offshore. Loggerhead and green turtle hatchlings seem to adopt an intensely vigorous and energetically costly frenzy swim that would quickly take them offshore into the open ocean in order to reduce their exposure to near-shore aquatic predators. Flatback hatchlings, however, are restricted in geographic distribution and remain within the continental shelf region where predator pressure is probably relatively constant. For this reason, flatback hatchlings might use only part of their energy reserves during a less vigorous frenzy phase, with lower overall energy expenditure during the first day compared with loggerhead and green turtle hatchlings.
Kingfisher feathers – colouration by pigments, spongy nanostructures and thin films
Authors: Stavenga Doekele G. , Tinbergen Jan , Leertouwer Hein L. , Wilts Bodo D.
Published: November 2011

The colours of the common kingfisher, Alcedo atthis, reside in the barbs of the three main types of feather: the orange breast feathers, the cyan back feathers and the blue tail feathers. Scanning electron microscopy showed that the orange barbs contain small pigment granules. The cyan and blue barbs contain spongy nanostructures with slightly different dimensions, causing different reflectance spectra. Imaging scatterometry showed that the pigmented barbs create a diffuse orange scattering and the spongy barb structures create iridescence. The extent of the angle-dependent light scattering increases with decreasing wavelength. All barbs have a cortical envelope with a thickness of a few micrometres. The reflectance spectra of the cortex of the barbs show oscillations when measured from small areas, but when measured from larger areas the spectra become wavelength independent. This can be directly understood with thin film modelling, assuming a somewhat variable cortex thickness. The cortex reflectance appears to be small but not negligible with respect to the pigmentary and structural barb reflectance.
The recruiter's excitement – features of thoracic vibrations during the honey bee's waggle dance related to food source profitability
Authors: Hrncir Michael , Maia-Silva Camila , Mc Cabe Sofia I. , Farina Walter M.
Published: November 2011

The honey bee's waggle dance constitutes a remarkable example of an efficient code allowing social exploitation of available feeding sites. In addition to indicating the position (distance, direction) of a food patch, both the occurrence and frequency of the dances depend on the profitability of the exploited resource (sugar concentration, solution flow rate). During the waggle dance, successful foragers generate pulsed thoracic vibrations that putatively serve as a source of different kinds of information for hive bees, who cannot visually decode dances in the darkness of the hive. In the present study, we asked whether these vibrations are a reliable estimator of the excitement of the dancer when food profitability changes in terms of both sugar concentration and solution flow rate. The probability of producing thoracic vibrations as well as several features related to their intensity during the waggle phase (pulse duration, velocity amplitude, duty cycle) increased with both these profitability variables. The number of vibratory pulses, however, was independent of sugar concentration and reward rate exploited. Thus, pulse number could indeed be used by dance followers as reliable information about food source distance, as suggested in previous studies. The variability of the dancer's thoracic vibrations in relation to changes in food profitability suggests their role as an indicator of the recruiter's motivational state. Hence, the vibrations could make an important contribution to forager reactivation and, consequently, to the organisation of collective foraging processes in honey bees.
Pharmacological characterisation of apical Na+ and Cl– transport mechanisms of the anal papillae in the larval mosquitoAedes aegypti
Authors: Duca Olimpia Del , Nasirian Azadeh , Galperin Vladimir , Donini Andrew
Published: November 2011

The anal papillae of freshwater mosquito larvae are important sites of NaCl uptake, thereby acting to offset the dilution of the hemolymph by the dilute habitat. The ion-transport mechanisms in the anal papillae are not well understood. In this study, the scanning ion-selective electrode technique (SIET) was utilized to measure ion fluxes at the anal papillae, and pharmacological inhibitors of ion transport were utilized to identify ion-transport mechanisms. Na+ uptake by the anal papillae was inhibited by bafilomycin and phenamil but not by HMA. Cl– uptake was inhibited by methazolamide, SITS and DIDS but not by bafilomycin. H+ secretion was inhibited by bafilomycin and methazolamide. Ouabain and bumetanide had no effect on NaCl uptake or H+ secretion. Together, the results suggest that Na+ uptake at the apical membrane occurs through a Na+ channel that is driven by a V-type H+-ATPase and that Cl– uptake occurs through a Cl–/HCO3– exchanger, with carbonic anhydrase providing H+ and HCO3– to the V-type H+-ATPase and exchanger, respectively.
Insights into Uranyl Ion Binding to Ubiquitin from Molecular Modeling and Dynamics Simulations
Authors: Lin Ying-Wu , Nie Chang-Ming , Liao Li-Fu
Published: November 2011

Uranium is toxic to the human body with mechanisms not fully understood. The interaction between uranyl ion (UO22+) and ubiquitin (Ub) was predicted by molecular modeling, molecular dynamics (MD) simulation, and steered molecular dynamics (SMD) simulation. The structural and dynamics consequences, as well as protein unfolding behavior, upon uranyl binding to two surface residues of Ub, Glu18 and Asp21, were revealed at an atomic level. This in silico study exhibits a possibility of UO22+ binding to Ub, providing a possible mechanism of uranyl toxicity in vivo.
Stent-graft placement for urgent treatment or prevention of bleeding
Authors: Semiz-Oysu Aslihan , Keussen Inger , Cwikiel Wojciech
Published: November 2011

Background

Stent-graft treatment of the patients with ongoing bleeding may be beneficial in specific situations, especially when preservation of blood flow to the distant organs is important.

Purpose

To present the results of stent-graft placement for urgent treatment or prevention of the bleeding.

Material and Methods

Stent-graft placement was performed urgently for the treatment of active bleeding and/or pseudoaneurysm/aneurysm in 17 patients. Diagnoses were based on clinical findings and/or imaging studies. The etiology was previous major surgery and/or percutaneous intervention in 13, malignancy in one, pancreatitis and pseudocyst in one, multitrauma due to traffic accident in one and unknown cause in one patient.

Results

A total of 23 stent-grafts were placed. Angiograms obtained after placement revealed patent stent-graft with no further active extravasation or filling of pseudoaneurysm in 14 patients. Due to persistent bleeding, embolization was performed in two patients. In three patients, the stent-grafts were found to be thrombosed either immediately after placement ( n = 1) or at follow-up ( n = 2). Stent-grafts were patent in six of nine patients that could be followed (between 3 months and 6 years).

Conclusion

Urgent stent-graft placement may be an alternative to endovascular embolization or surgery. It may be preferred when embolization is technically difficult or impossible and/or when preservation of blood supply to distal organs is essential such as in liver transplant grafts or extremity salvage.
FDG-PET/CT in the diagnosis of recurrent breast cancer
Authors: Murakami Ryusuke , Kumita Shin-ichiro , Yoshida Tamiko , Ishihara Keiichi , Kiriyama Tomonari , Hakozaki Kenta , Yanagihara Keiko , Iida Shinya , Tsuchiya Shin-ichi
Published: November 2011

Background

An advantage of PET/CT has been demonstrated for diagnosis of several tumor entities. In patients with breast cancer, early diagnosis and accurate restaging of recurrence after surgery is important for selection of the most appropriate therapeutic strategy.

Purpose

To evaluate the accuracy of integrated positron emission tomography and computed tomography (PET/CT) using 18F-fluorodeoxyglucose (FDG), for follow-up of patients with suspected recurrent breast cancer.

Material and Methods

Forty-seven patients with suspected recurrent breast cancer underwent PET/CT. The PET and PET/CT images were interpreted without knowledge of the results of other diagnostic modalities, and compared with each other with reference to the final diagnosis.

Results

Twenty-five (53%) patients suffered tumor recurrence. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT were 96%, 91%, 92%, 95%, and 94%, respectively. In comparison with PET, PET/CT had a higher sensitivity and accuracy (96% vs. 80% and 94% vs. 81%, respectively). The difference in diagnostic accuracy between PET/CT and PET was significant ( P < 0.05).

Conclusion

The present findings indicate that PET/CT is an accurate, sensitive and reliable modality for screening and detection of breast cancer recurrence. PET/CT appears to be an effective surveillance tool, as it is able to cover the whole body in a single procedure and shows good performance.
Predictive Discomfort and Seat-to-Head Transmissibility in Low-Frequency Fore-Aft Whole-Body Vibration
Authors: DeShaw Jonathan , Rahmatalla Salam
Published: November 2011

A predictive discomfort measure considering the combined neck and trunk is introduced in this work and compared with the seat-to-head transmissibility and subjective reported discomfort due to fore-aft whole-body vibration of seated subjects under two sitting postures. Five subjects were tested using discrete sinusoidal frequencies in the range of 0.5–12 Hz. All files were run at a constant acceleration of 0.8 m/s2. The subjects were tested with back support and without back support, and their subjective discomfort measure was reported based on the Borg CR-10 scale. The results have demonstrated that the predictive discomfort was invulnerable to the measurement locations and has shown consistency with the subjective discomfort for both sitting conditions. The seat-to-head transmissibility showed less consistency with the subjective discomfort and was sensitive to the locations of the output point on the head and to the components of the motion included in the transmissibility calculation at these locations.
Examination of Vibration Characteristics, and Reported Musculoskeletal Discomfort for Workers Exposed to Vibration via the Feet
Authors: Leduc Mallorie , Eger Tammy , Godwin Alison , Dickey James P. , House Ron
Published: November 2011

The frequency and amplitude characteristics of vibration experienced at the feet under typical mining equipment operation were documented in this study. Foot-transmitted vibration (FTV) was measured using a tri-axial accelerometer mounted at the location where the worker stood. A musculoskeletal disorder questionnaire, work history and demographic information were also collected. Vibration from locomotives (primary source exposure) had a dominant frequency below 6.3 Hz; whereas, drilling and raise platforms (secondary source exposures) were predominantly in the 31.5 to 40 Hz range. All workers reported lower limb discomfort and two had been diagnosed with vibration induced white feet. All raise platforms exposed the workers to vibration levels that placed them above the ISO 2631–1 health guidance caution zone for an 8-hour exposure. Further investigation using both ISO 2631–1 and ISO 5341–1 standards is needed to determine long-term health effects to the whole-body and feet of workers exposed to FTV.
Noise Reduction of a Fan and Air Duct by Using a Plenum Chamber Based on ASHRAE Guidelines
Authors: Forouharmajd Farhad , Nassiri Parvin
Published: November 2011

Noise propagates from sources through air distribution duct systems, structures, and combinations of paths, reaching the occupants. A plenum chamber is similar to a dissipative silencer, but it is also similar to a small room with a noise source in one wall. The dimensions of the plenum chamber are usually larger than the wavelength of the sound being attenuated. Above the cutoff frequency, as defined by the plenum's inlet duct dimensions, the wavelength of sound is small compared to the characteristic dimensions of the plenum. All values are in terms of sound pressure level with “A” frequency weighting and “slow” time weighting measured by a B&K 2231 sound level meter and 1625 analyzer. Input and output in this compartment as opposed to a two-sided compartment was based on the ASHRAE instructions on the frequency of cutoff. This frequency indicates that the chamber dimensions that channel input and output frequencies higher than 436 Hz will be effective in reducing noise.
Using Statistical Analysis as an Additional Tool in Porous Solid Characterization
Authors: Attipa Christothea , Panayiotou Antonia , Kokkinofta Rebecca , Theocharis Charis R.
Published: November 2011

Analytical chemists have long used statistical methods to help them organize and interpret experimental data — especially where large numbers of these are generated — as well as to help them design new experiments. Recently, chemometrics has found applications in wider fields, such as the determination of the geographical origin of food and other products. During the past several years, we have carried out a systematic study of the factors affecting the pore structure and surface chemistry of cerium oxide and of mixed oxides of cerium with various transition metal or alkaline earth metal ions.