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Substrate-Mediated Laser Ablation under Ambient Conditions for Spatially-Resolved Tissue Proteomics

Fatou, Benoit; Wisztorski, Maxence; Focsa, Cristian; Salzet, Michel; Ziskind, Michael; Fournier, Isabelle
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
Numerous applications of ambient Mass Spectrometry (MS) have been demonstrated over the past decade. They promoted the emergence of various micro-sampling techniques such as Laser Ablation/Droplet Capture (LADC). LADC consists in the ablation of analytes from a surface and their subsequent capture in a solvent droplet which can then be analyzed by MS. LADC is thus generally performed in the UV or IR range, using a wavelength at which analytes or the matrix absorb. In this work, we explore the potential of visible range LADC (532 nm) as a micro-sampling technology for large-scale proteomics analyses. We demonstrate that biomolecule analyses using 532 nm LADC are possible, despite the low absorbance of biomolecules at this wavelength. This is due to the preponderance of an indirect substrate-mediated ablation mechanism at low laser energy which contrasts with the conventional direct ablation driven by sample absorption. Using our custom LADC system and taking advantage of this substrate-mediated ablation mechanism, we were able to perform large-scale proteomic analyses of micro-sampled tissue sections and demonstrated the possible identification of proteins with relevant biological functions. Consequently, the 532 nm LADC technique offers a new tool for biological and clinical applications.

The pan-class I phosphatidyl-inositol-3 kinase inhibitor NVP-BKM120 demonstrates anti-leukemic activity in acute myeloid leukemia

Allegretti, Matteo; Ricciardi, Maria Rosaria; Licchetta, Roberto; Mirabilii, Simone; Orecchioni, Stefania; Reggiani, Francesca; Talarico, Giovanna; Foà, Roberto; Bertolini, Francesco; Amadori, Sergio; Torrisi, Maria Rosaria; Tafuri, Agostino
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
Aberrant activation of the PI3K/Akt/mTOR pathway is a common feature of acute myeloid leukemia (AML) patients contributing to chemoresistance, disease progression and unfavourable outcome. Therefore, inhibition of this pathway may represent a potential therapeutic approach in AML. The aim of this study was to evaluate the pre-clinical activity of NVP-BKM120 (BKM120), a selective pan-class I PI3K inhibitor, on AML cell lines and primary samples. Our results demonstrate that BKM120 abrogates the activity of the PI3K/Akt/mTOR signaling, promoting cell growth arrest and significant apoptosis in a dose- and time-dependent manner in AML cells but not in the normal counterpart. BKM120-induced cytotoxicity is associated with a profound modulation of metabolic behaviour in both cell lines and primary samples. In addition, BKM120 synergizes with the glycolitic inhibitor dichloroacetate enhancing apoptosis induction at lower doses. Finally, in vivo administration of BKM120 to a xenotransplant mouse model of AML significantly inhibited leukemia progression and improved the overall survival of treated mice. Taken together, our findings indicate that BKM120, alone or in combination with other drugs, has a significant anti-leukemic activity supporting its clinical development as a novel therapeutic agent in AML.

Giant barocaloric effect in hexagonal Ni2In-type Mn-Co-Ge-In compounds around room temperature

Wu, Rong-Rong; Bao, Li-Fu; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Wang, Jing; Dong, Xiao-Li; Li, Guan-Nan; Sun, Ji-Rong; Shen, Fei-Ran; Zhao, Tong-Yun; Zheng, Xin-Qi; Wang, Li-Chen; Liu, Yao; Zuo, Wen-Liang; Zhao, Ying-Ying; Zhang, Ming; Wang, Xian-Chen
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
The most widespread cooling techniques based on gas compression/expansion encounter environmental problems. Thus, tremendous effort has been dedicated to develop alternative cooling technique and search for solid state materials that show large caloric effects. An application of pressure to a material can cause a change in temperature, which is called the barocaloric effect. Here we report the giant barocaloric effect in a hexagonal Ni2In-type MnCoGe0.99In0.01 compound involving magnetostructural transformation, Tmstr, which is accompanied with a big difference in the internal energy due to a great negative lattice expansion(ΔV/V ~ 3.9%). High resolution neutron diffraction experiments reveal that the hydrostatic pressure can push the Tmstr to a lower temperature at a rate of 7.7 K/kbar, resulting in a giant barocaloric effect. The entropy change under a moderate pressure of 3 kbar reaches 52 Jkg−1K−1, which exceeds that of most materials, including the reported giant magnetocaloric effect driven by 5 T magnetic field that is available only by superconducting magnets.

Prosthetic-Joint-Associated Bordetella holmesii Infection

Humphrey, John M.; Lacaille, Sherard N. J.; Patel, Krutika; Thompson, Erin; Tulumba, Steve; Healey, John H.; Gilhuley, Kathleen A.; Babady, N. Esther; Kamboj, Mini; Mead, Peter A.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Text
Publicado em 13/11/2015 Português
Bordetella holmesii is a globally distributed pathogen that is increasingly recognized as a cause of both pertussis-like respiratory infections and invasive disease. In this study, we describe a case of an immunocompetent man who developed B holmesii infection of his femoral prosthesis—the fifth B holmesii orthopedic infection reported in literature to date. This article highlights the potentially underrecognized role of B holmesii in orthopedic infections by reviewing these previously reported cases in the context of the current literature.

Fusarinine C, a novel siderophore-based bifunctional chelator for radiolabeling with Gallium-68

Zhai, Chuangyan; Summer, Dominik; Rangger, Christine; Haas, Hubertus; Haubner, Roland; Decristoforo, Clemens
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Fusarinine C (FSC), a siderophore-based chelator coupled with the model peptide c(RGDfK) (FSC(succ-RGD)3), revealed excellent targeting properties in vivo using positron emission tomography (PET). Here, we report the details of radiolabeling conditions and specific activity as well as selectivity for 68Ga.

Paving the way to nanoionics: atomic origin of barriers for ionic transport through interfaces

Frechero, M. A.; Rocci, M.; Sánchez-Santolino, G.; Kumar, Amit; Salafranca, J.; Schmidt, Rainer; Díaz-Guillén, M. R.; Durá, O. J.; Rivera-Calzada, A.; Mishra, R.; Jesse, Stephen; Pantelides, S. T.; Kalinin, Sergei V.; Varela, M.; Pennycook, S. J.; San
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
The blocking of ion transport at interfaces strongly limits the performance of electrochemical nanodevices for energy applications. The barrier is believed to arise from space-charge regions generated by mobile ions by analogy to semiconductor junctions. Here we show that something different is at play by studying ion transport in a bicrystal of yttria (9% mol) stabilized zirconia (YSZ), an emblematic oxide ion conductor. Aberration-corrected scanning transmission electron microscopy (STEM) provides structure and composition at atomic resolution, with the sensitivity to directly reveal the oxygen ion profile. We find that Y segregates to the grain boundary at Zr sites, together with a depletion of oxygen that is confined to a small length scale of around 0.5 nm. Contrary to the main thesis of the space-charge model, there exists no evidence of a long-range O vacancy depletion layer. Combining ion transport measurements across a single grain boundary by nanoscale electrochemical strain microscopy (ESM), broadband dielectric spectroscopy measurements, and density functional calculations, we show that grain-boundary-induced electronic states act as acceptors, resulting in a negatively charged core. Besides the possible effect of the modified chemical bonding...

Comparative transcriptome analysis of grapevine in response to copper stress

Leng, Xiangpeng; Jia, Haifeng; Sun, Xin; Shangguan, Lingfei; Mu, Qian; Wang, Baoju; Fang, Jinggui
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
Grapevine is one of the most economically important and widely cultivated fruit crop worldwide. With the industrialization and the popular application of cupric fungicides in grape industry, copper stress and copper pollution are also the factors affecting grape production and berry and wine quality. Here, 3,843 transcripts were significantly differently expressed genes in response to Cu stress by RNA-seq, which included 1,892 up-regulated and 1,951 down-regulated transcripts. During this study we found many known and novel Cu-induced and -repressed genes. Biological analysis of grape samples were indicated that exogenous Cu can influence chlorophylls metabolism and photosynthetic activities of grapevine. Most ROS detoxification systems, including antioxidant enzyme, stress-related proteins and secondary metabolites were strongly induced. Concomitantly, abscisic acid functioned as a negative regulator in Cu stress, in opposite action to ethylene, auxin, jasmonic acid, and brassinolide. This study also identified a set of Cu stress specifically activated genes coding copper transporter, P1B-type ATPase, multidrug transporters. Overall, this work was carried out to gain insights into the copper-regulated and stress-responsive mechanisms in grapevine at transcriptome level. This research can also provide some genetic information that can help us in better vinery management and breeding Cu-resistant grape cultivars.

Effect of edge pruning on structural controllability and observability of complex networks

Mengiste, Simachew Abebe; Aertsen, Ad; Kumar, Arvind
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
Controllability and observability of complex systems are vital concepts in many fields of science. The network structure of the system plays a crucial role in determining its controllability and observability. Because most naturally occurring complex systems show dynamic changes in their network connectivity, it is important to understand how perturbations in the connectivity affect the controllability of the system. To this end, we studied the control structure of different types of artificial, social and biological neuronal networks (BNN) as their connections were progressively pruned using four different pruning strategies. We show that the BNNs are more similar to scale-free networks than to small-world networks, when comparing the robustness of their control structure to structural perturbations. We introduce a new graph descriptor, ‘the cardinality curve’, to quantify the robustness of the control structure of a network to progressive edge pruning. Knowing the susceptibility of control structures to different pruning methods could help design strategies to destroy the control structures of dangerous networks such as epidemic networks. On the other hand, it could help make useful networks more resistant to edge attacks.

HIV-1 CCR5 gene therapy will fail unless it is combined with a suicide gene

Pandit, Aridaman; de Boer, Rob J.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Text
Publicado em 17/12/2015 Português
Highly active antiretroviral therapy (ART) has successfully turned Human immunodeficiency virus type 1 (HIV-1) from a deadly pathogen into a manageable chronic infection. ART is a lifelong therapy which is both expensive and toxic, and HIV can become resistant to it. An alternative to lifelong ART is gene therapy that targets the CCR5 co-receptor and creates a population of genetically modified host cells that are less susceptible to viral infection. With generic mathematical models we show that gene therapy that only targets the CCR5 co-receptor fails to suppress HIV-1 (which is in agreement with current data). We predict that the same gene therapy can be markedly improved if it is combined with a suicide gene that is only expressed upon HIV-1 infection.

Cellular and Muscular Growth Patterns During Sipunculan Development

KRISTOF, ALEN; WOLLESEN, TIM; MAIOROVA, ANASTASSYA S.; WANNINGER, ANDREAS
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Sipuncula is a lophotrochozoan taxon with annelid affinities, albeit lacking segmentation of the adult body. Here, we present data on cell proliferation and myogenesis during development of three sipunculan species, Phascolosoma agassizii, Thysanocardia nigra, and Themiste pyroides. The first anlagen of the circular body wall muscles appear simultaneously and not subsequently as in the annelids. At the same time, the rudiments of four longitudinal retractor muscles appear. This supports the notion that four introvert retractors were part of the ancestral sipunculan bodyplan. The longitudinal muscle fibers form a pattern of densely arranged fibers around the retractor muscles, indicating that the latter evolved from modified longitudinal body wall muscles. For a short time interval, the distribution of S-phase mitotic cells shows a metameric pattern in the developing ventral nerve cord during the pelagosphera stage. This pattern disappears close to metamorphic competence. Our findings are congruent with data on sipunculan neurogenesis, as well as with recent molecular analyses that place Sipuncula within Annelida, and thus strongly support a segmental ancestry of Sipuncula.

Pediatric treatment 2.0: ensuring a holistic response to caring for HIV-exposed and infected children

Essajee, Shaffiq M.; Arpadi, Stephen M.; Dziuban, Eric J.; Gonzalez-Montero, Raul; Heidari, Shirin; Jamieson, David G.; Kellerman, Scott E.; Koumans, Emilia; Ojoo, Atieno; Rivadeneira, Emilia; Spector, Stephen A.; Walkowiak, Helena;
Fonte: PubMed Publicador: PubMed
Tipo: Text
Publicado em /11/2013 Português
Treatment 2.0 is an initiative launched by UNAIDS and WHO in 2011 to catalyze the next phase of treatment scale-up for HIV. The initiative defines strategic activities in 5 key areas, drugs, diagnostics, commodity costs, service delivery and community engagement in an effort to simplify treatment, expand access and maximize program efficiency. For adults, many of these activities have already been turned into treatment policies. The recent WHO recommendation to use a universal first line regimen regardless of gender, pregnancy and TB status is a treatment simplification very much in line with Treatment 2.0. But despite that fact that Treatment 2.0 encompasses all people living with HIV, we have not seen the same evolution in policy development for children. In this paper we discuss how Treatment 2.0 principles can be adapted for the pediatric population. There are several intrinsic challenges. The need for distinct treatment regimens in children of different ages makes it hard to define a one size fits all approach. In addition, the fact that many providers are reluctant to treat children without the advice of specialists can hamper decentralization of service delivery. But at the same time, there are opportunities that can be availed now and in the future to scale up pediatric treatment along the lines of Treatment 2.0. We examine each of the five pillars of Treatment 2.0 from a pediatric perspective and present eight specific action points that would result in simplification of pediatric treatment and scale up of HIV services for children.

Patient-Physician Discussions of Colorectal Cancer Screening: Delivery of the 5 ‘As’ in Practice

Lafata, Jennifer Elston; Cooper, Gregory S.; Divine, George; Flocke, Susan A.; Oja-Tebbe, Nancy; Stange, Kurt C.; Wunderlich, Tracy
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português

IFPA Meeting 2012 Workshop Report II: Epigenetics and imprinting in the placenta, growth factors and villous trophoblast differentiation, role of the placenta in regulating fetal exposure to xenobiotics during pregnancy, infection and the placenta

Ahmed, M.S.; Aleksunes, L.M.; Boeuf, P.; Chung, M.K.; Daoud, G.; Desoye, G.; Díaz, P.; Golos, T.G.; Illsley, N.P.; Kikuchi, K.; Komatsu, R.; Lao, T.; Morales-Prieto, D.M.; Nanovskaya, T.; Nobuzane, T.; Roberts, C.T.; Saffery, R.; Tamura, I.; Tamura, K.;
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, four of which are summarized in this report. These workshops related to various aspects of placental biology: 1) epigenetics and imprinting in the placenta; 2) growth factors and villous trophoblast differentiation; 3) role of the placenta in regulating fetal exposure to xenobiotics during pregnancy; 4) infection and the placenta.

Life on the edge: Thermal optima for aerobic scope of equatorial reef fishes are close to current day temperatures

Rummer, Jodie L.; Couturier, Christine S.; Stecyk, Jonathan A. W.; Gardiner, Naomi M.; Kinch, Jeff P.; Nilsson, Göran E.; Munday, Philip L.
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Equatorial populations of marine species are predicted to be most impacted by global warming because they could be adapted to a narrow range of temperatures in their local environment. We investigated the thermal range at which aerobic metabolic performance is optimum in equatorial populations of coral reef fish in northern Papua New Guinea. Four species of damsel fishes and two species of cardinal fishes were held for 14d at 29, 31, 33, and 34°C, which incorporated their existing thermal range (29–31°C) as well as projected increases in ocean surface temperatures of up to 3°C by the end of this century. Resting and maximum oxygen consumption rates were measured for each species at each temperature and used to calculate the thermal reaction norm of aerobic scope. Our results indicate that one of the six species, Chromisatripectoralis, is already living above its thermal optimum of 29°C. The other five species appeared to be living close to their thermal optima (approximately 31°C). Aerobic scope was significantly reduced in all species, and approached zero for two species at 3°C above current-day temperatures. One species was unable to survive even short-term exposure to 34°C. Our results indicate that low-latitude reef fish populations are living close to their thermal optima and may be more sensitive to ocean warming than higher-latitude populations. Even relatively small temperature increases (2–3°C) could result in population declines and potentially redistribution of equatorial species to higher latitudes if adaptation cannot keep pace.

Prolyl Oligopeptidase Is Involved in Release of the Antifibrotic Peptide Ac-SDKP

Cavasin, Maria A.; Rhaleb, Nour-Eddine; Yang, Xiao-Ping; Carretero, Oscar A.
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a ubiquitous tetrapeptide hydrolyzed almost exclusively by angiotensin-converting enzyme (ACE). Chronic treatment with Ac-SDKP decreases cardiac and renal fibrosis and inflammatory cell infiltration in hypertensive rats. However, very little is known about endogenous synthesis of Ac-SDKP, except that thymosin-β4 may be the most likely precursor. Two enzymes are potentially able to release Ac-SDKP from thymosin-β4: prolyl oligopeptidase (POP) and endoproteinase asp-N. POP is widely present and active in several tissues and biological fluids, whereas endoproteinase asp-N appears to be lacking in mammals. Therefore, we hypothesized that POP is the main enzyme involved in synthesizing the antifibrotic peptide Ac-SDKP. We investigated in vitro and in vivo production of Ac-SDKP. Using kidney cortex homogenates, we observed that Ac-SDKP was generated in a time-dependent manner in the presence of exogenous thymosin-β4, and this generation was significantly inhibited by several POP inhibitors (POPi), Z-prolyl-prolinal, Fmoc-prolyl-pyrrolidine-2-nitrile, and S17092. Long-term administration of S17092 in rats significantly decreased endogenous levels of Ac-SDKP in the plasma (from 1.76±0.2 to 1.01±0.1 nM)...

Molecular insights into the progression of crystalline silica-induced pulmonary toxicity in rats

Sellamuthu, Rajendran; Umbright, Christina; Roberts, Jenny R.; Cumpston, Amy; McKinney, Walter; Chen, Bean T.; Frazer, David; Li, Shengqiao; Kashon, Michael; Joseph, Pius
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Identification of molecular target(s) and mechanism(s) of silica-induced pulmonary toxicity is important for the intervention and/or prevention of diseases associated with exposure to silica. Rats were exposed to crystalline silica by inhalation (15 mg m−3, 6 h per day, 5 days) and global gene expression profile was determined in the lungs by microarray analysis at 1, 2, 4, 8 and 16 weeks following termination of silica exposure. The number of significantly differentially expressed genes (>1.5-fold change and <0.01 false discovery rate P-value) detected in the lungs during the post-exposure time intervals analyzed exhibited a steady increase in parallel with the progression of silica-induced pulmonary toxicity noticed in the rats. Quantitative real-time PCR analysis of a representative set of 10 genes confirmed the microarray findings. The number of biological functions, canonical pathways and molecular networks significantly affected by silica exposure, as identified by the bioinformatics analysis of the significantly differentially expressed genes detected during the post-exposure time intervals, also exhibited a steady increase similar to the silica-induced pulmonary toxicity. Genes involved in oxidative stress, inflammation, respiratory diseases...

Joint modeling of survival and longitudinal non-survival data: current methods and issues. Report of the DIA Bayesian joint modeling working group

Gould, A. Lawrence; Boye, Mark Ernest; Crowther, Michael J.; Ibrahim, Joseph G.; Quartey, George; Micallef, Sandrine; Bois, Frederic Y.
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
Explicitly modeling underlying relationships between a survival endpoint and processes that generate longitudinal measured or reported outcomes potentially could improve the efficiency of clinical trials and provide greater insight into the various dimensions of the clinical effect of interventions included in the trials. Various strategies have been proposed for using longitudinal findings to elucidate intervention effects on clinical outcomes such as survival. The application of specifically Bayesian approaches for constructing models that address longitudinal and survival outcomes explicitly has been recently addressed in the literature. We review currently available methods for carrying out joint analyses, including issues of implementation and interpretation, identify software tools that can be used to carry out the necessary calculations, and review applications of the methodology.

Laboratory and field measurements and evaluations of vibration at the handles of riveting hammers

McDOWELL, THOMAS W.; WARREN, CHRISTOPHER; WELCOME, DANIEL E.; DONG, REN G.
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português
The use of riveting hammers can expose workers to harmful levels of hand-transmitted vibration (HTV). As a part of efforts to reduce HTV exposures through tool selection, the primary objective of this study was to evaluate the applicability of a standardized laboratory-based riveting hammer assessment protocol for screening riveting hammers. The second objective was to characterize the vibration emissions of reduced vibration riveting hammers and to make approximations of the HTV exposures of workers operating these tools in actual work tasks. Eight pneumatic riveting hammers were selected for the study. They were first assessed in a laboratory using the standardized method for measuring vibration emissions at the tool handle. The tools were then further assessed under actual working conditions during three aircraft sheet metal riveting tasks. Although the average vibration magnitudes of the riveting hammers measured in the laboratory test were considerably different from those measured in the field study, the rank orders of the tools determined via these tests were fairly consistent, especially for the lower vibration tools. This study identified four tools that consistently exhibited lower frequency-weighted and unweighted accelerations in both the laboratory and workplace evaluations. These observations suggest that the standardized riveting hammer test is acceptable for identifying tools that could be expected to exhibit lower vibrations in workplace environments. However...

Trichomonas vaginalis in Selected US Sexually Transmitted Disease Clinics: Testing, Screening, and Prevalence

Meites, Elissa; Llata, Eloisa; Braxton, Jim; Schwebke, Jane R.; Bernstein, Kyle T.; Pathela, Preeti; Asbel, Lenore E.; Kerani, Roxanne P.; Mettenbrink, Christie J.; Weinstock, Hillard S.
Fonte: PubMed Publicador: PubMed
Tipo: Text
Publicado em /11/2013 Português

Trichomoniasis: The “Neglected” Sexually Transmitted Disease

Meites, Elissa
Fonte: PubMed Publicador: PubMed
Tipo: Text
Português