3,322 research outputs found

    Histologic study of ossification of the thyroid cartilage

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    The process of ossification and formation of bone marrow occurs in the larynx cartilages with age. The knowledge of this change is important for differentiation with cartilage invasion by cancer. AIM: Cranial and caudal segments of the thyroid cartilage were obtained from adult male larynges in order to evaluate comparatively the histological changes regarding to the ossification and the bone marrow formation. STUDY DESIGN: Experimental. MATERIAL AND METHOD: Seven male adult larynges were obtained from cadavers underwent necrological examination in Posto Médico-Legal de Santos, da Polícia Civil do Estado de São Paulo. The ages ranged from 39 to 60, with median of 53. There were no available data about tobacco and alcohol consumption. The specimens underwent decalcification and stained with H-E. Histometry was performed for quantitative analysis of the ossification while the bone marrow was analyzed according to qualitative criteria (presence or absence). RESULTS: The average ossification was 42.8% and the bone marrow presence was observed in 57.1% in the cranial segments. In the caudal segments, the average ossification was 72.8%, and the bone marrow was detected in 87.5% of the specimens. CONCLUSION: The ossification in the thyroid cartilage and the bone marrow formation increase and occur earlier moving downward from the cranial to the caudal aspects.Com o passar da idade, ocorrem progressivamente ossificação e formação de medula óssea nas cartilagens laríngeas. O conhecimento dessas modificações é importante para a diferenciação com invasão por câncer. OBJETIVO: Avaliar comparativamente as porções cranial e caudal da cartilagem tireóidea quanto a alterações histológicas em indivíduos adultos do sexo masculino, observando a ossificação e a formação de medula óssea. FORMA DE ESTUDO: Experimental. MATERIAL E MÉTODO: Foram estudadas 7 laringes obtidas de cadáveres do sexo masculino submetidos a exame necrológico no Posto Médico-Legal de Santos, da Polícia Civil do Estado de São Paulo. A idade variou de 39 a 60 anos, com mediana de 53. Não se teve acesso à informação de hábito de tabagismo e etilismo. Os espécimes foram descalcificados e corados pela hematoxilina-eosina. A ossificação foi estudada pelo método histométrico baseado na estereologia e a presença de medula óssea foi realizada de forma qualitativa (presença ou ausência). RESULTADOS: Nos segmentos craniais, notamos uma média de 42,8% de ossificação e a presença de medula óssea em 57,1%. Nos segmentos caudais, a média de ossificação foi de 72,8%, com medula óssea em 87,5%. CONCLUSÃO: A ossificação da cartilagem tireóidea e a formação de medula óssea são mais intensas e precoces na sua topografia cranial.Hospital HeliópolisUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaHospital Ana Costa Serviço de Anatomia PatológicaUniversidade de São PauloUNIFESP, EPMSciEL

    Soft X-ray spectral variations of the narrow line Seyfert l galaxy Markarian 766

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    The X-ray variability of the narrow-line Seyfert 1 galaxy Markarian 766 is studied using nine ROSAT PSPC data sets. The spectrum is well described by a power law combined with a blackbody (kT ∼ 70 eV) soft excess. Examination of flux ratio changes and variability amplitude in three X-ray bands shows that the power-law component varies continuously on time-scales of ∼ 5000 s and is steeper when it is brighter. In contrast, variability of the soft excess is not detected. Spectral modelling of 31 spectra from different observations and at a range of count rates is also consistent with a picture in which the power law is steeper when it is brighter, and in which the soft-excess component does not vary. The power-law variability can be explained if the power law is produced by variable thermal or non-thermal Comptonization of soft photons. This behaviour is similar to that of Galactic black hole candidates in the low state. The X-ray and multiwavelength properties of Markarian 766 are shown to be very similar to those of other narrow-line Seyfert 1s. This may mean that the rapid X-ray variability seen in other narrow-line Seyfert 1s may also not originate in their strong soft-excess components

    An Infrared/X-ray Survey for New Members of the Taurus Star-Forming Region

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    We present the results of a search for new members of the Taurus star-forming region using data from the Spitzer Space Telescope and the XMM-Newton Observatory. We have obtained optical and near-infrared spectra of 44 sources that exhibit red Spitzer colors that are indicative of stars with circumstellar disks and 51 candidate young stars that were identified by Scelsi and coworkers using XMM-Newton. We also performed spectroscopy on four possible companions to members of Taurus that were reported by Kraus and Hillenbrand. Through these spectra, we have demonstrated the youth and membership of 41 sources, 10 of which were independently confirmed as young stars by Scelsi and coworkers. Five of the new Taurus members are likely to be brown dwarfs based on their late spectral types (>M6). One of the brown dwarfs has a spectral type of L0, making it the first known L-type member of Taurus and the least massive known member of the region (M=4-7 M_Jup). Another brown dwarf exhibits a flat infrared spectral energy distribution, which indicates that it could be in the protostellar class I stage (star+disk+envelope). Upon inspection of archival images from various observatories, we find that one of the new young stars has a large edge-on disk (r=2.5=350 AU). The scattered light from this disk has undergone significant variability on a time scale of days in optical images from the Canada-France-Hawaii Telescope. Using the updated census of Taurus, we have measured the initial mass function for the fields observed by XMM-Newton. The resulting mass function is similar to previous ones that we have reported for Taurus, showing a surplus of stars at spectral types of K7-M1 (0.6-0.8 M_sun) relative to other nearby star-forming regions like IC 348, Chamaeleon I, and the Orion Nebula Cluster

    Status of Coral Reefs in the US Caribbean and Gulf of Mexico: Florida, Texas, Puerto Rico, US Virgin Islands and Navassa

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    The following report on the status of US Caribbean coral reef ecosystems has been summarised from more extensive reports submitted to the US Coral Reef Task Force (USCRTF) working group that implemented in 2000 ‘A National Program to Assess, Inventory, and Monitor US Coral Reef Ecosystems’. The more-lengthy reports are also the basis for the biennial-issued document, ‘Status and Trends of US Coral Reef Ecosystems’. Each author is a recognised technical expert with responsibility for monitoring and/or managing aspects of their respective coral reef ecosystems

    The safety of monoclonal antibodies in asthma

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    Introduction: In the last two decades the knowledge of the mechanisms of the inflammatory processes underlying asthma rapidly evolved, several key mediators (cytokines and receptors) were identified, and the laboratory techniques have allowed us to synthesize monoclonal antibodies highly specific for those target molecules. Nowadays, many biological agents are investigated in asthma (with anti IgE being the only commercially available). The clinical efficacy of some biologics was demonstrated in many cases, however, the safety issue has progressively emerged and has been recognized as a crucial aspect. Areas covered: We summarized the currently available knowledge on the safety and side effects of biologics in asthma, as derived by reviews, meta analyses and clinical trials. PubMed was searched with the terms anti IL-x [AND] safety [OR] side effects, within the categories \u201cclinical trial\u201d, meta-analysis\u201d and \u201creview\u201d. Case reports were excluded. The authors collegially selected the relevant entries to be included. Expert opinion: Overall, the safety of most of the investigated agents seems to be satisfactory, a certain risk of side effects remains present, and is variable for the different molecules. Thus caution must be paid in evaluating the risk to benefit ratio. Specific biomarkers to predict the response to each biological are urgently needed to improve the safety profile

    The Disk Population of the Taurus Star-Forming Region

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    We have analyzed nearly all images of the Taurus star-forming region at 3.6-24um that were obtained during the cryogenic mission of the Spitzer Space Telescope (46 deg^2) and have measured photometry for all known members of the region that are within these data, corresponding to 348 sources. We have classified the members of Taurus according to whether they show evidence of disks and envelopes (classes I, II, and III). The disk fraction in Taurus is 75% for solar-mass stars and declines to 45% for low-mass stars and brown dwarfs (0.01-0.3 M_sun). This dependence on stellar mass is similar to that measured for Cha I, although the disk fraction in Taurus is slightly higher overall, probably because of its younger age (1 vs. 2-3 Myr). In comparison, the disk fraction for solar-mass stars is much lower (20%) in IC 348 and Sigma Ori, which are denser than Taurus and Cha I and are roughly coeval with the latter. These data indicate that disk lifetimes for solar-mass stars are longer in regions that have lower stellar densities. Through an analysis of multiple epochs of photometry that are available for ~200 Taurus members, we find that stars with disks exhibit significantly greater mid-IR variability than diskless stars. Finally, we have used our data in Taurus to refine the criteria for primordial, evolved, and transitional disks. The number ratio of evolved and transitional disks to primordial disks in Taurus is 15/98 for K5-M5, indicating a timescale of 0.15 x tau(primordial)=0.45 Myr for the clearing of the inner regions of optically thick disks. After applying the same criteria to older clusters (2-10 Myr), we find that the proportions of evolved and transitional disks in those populations are consistent with the measurements in Taurus when their star formation histories are properly taken into account. ERRATUM: In Table 7, we inadvertently omitted the spectral type bins in which class II sources were placed in Table 8 based on their bolometric luminosities (applies only to stars that lack spectroscopic classifications). The bins were K6-M3.5 for FT Tau, DK Tau B, and IRAS 04370+2559, M3.5-M6 for IRAS 04200+2759, IT Tau B, and ITG 1, and M6-M8 for IRAS 04325+2402 C. In addition, the values of K_s-[3.6] in Table 13 and Figure 26 for spectral types of M4-M9 are incorrect. We present corrected versions of Table 13 and Figure 26.Comment: revised version with Erratum (in press

    Tropical forests post-logging are a persistent net carbon source to the atmosphere

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    Acknowledgments This study was part of the SAFE Project, the Global Ecosystems Monitoring network (gem.tropicalforests.ox.ac.uk) and Imperial College's Grand Challenges in Ecosystems and the Environment Initiative. We acknowledge funding from the Sime Darby Foundation, the Biodiversity And Land-use Impacts on tropical ecosystem function (BALI) Project (NE/K016377/1) within the Natural Environment Research Council Human-Modified Tropical Forests Programme, the Malaysian Palm Oil Board (MPOB), and Centre for Tropical Forest Science (CTFS) in collaboration with HSBC Climate Partnership. The 52-ha Long-Term Ecological Research Project in Lambir is a collaborative project of the Forest Department of Sarawak, Malaysia, the Center for Tropical Forest Science of the Smithsonian Tropical Research Institute, USA (NSF awards DEB- 9107247 and DEB- 9629601), and Osaka City, Ehime & Kyoto Universities, Japan (Monbusho grants 06041094, 08NP0901 and 09NP0901). M.B.M. was supported by NERC studentship awarded through the Central England NERC Training Alliance (CENTA; grant referenceNE/S007350/1) and the University of Leicester, Y.M. was supported by the Jackson Foundation and European Research Council Advanced Investigator Grant, GEM-TRAIT (321131), Y.M., RME, and T.R. by NERC grant NE/P002218/1, and R.M.E. is supported by the NOMIS Foundation. TR also acknowledges support from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 865403). Maliau Basin and Danum Valley Management Committees, Royal Society South East Asia Rainforest Research Partnership (SEARRP), Sabah Foundation, Benta Wawasan, the State Secretary, Sabah Chief Minister’s Departments, Sabah Forestry Department, Sabah Biodiversity Council, and the Economic Planning Unit are acknowledged for their support and access to the sites in Sabah. Rostin Jantan, Rohid Kailoh, Suhaini Patik, Ampat Siliwong, Yehezekiel Jahuri, Robecca Siwaring, Jeffry Amin, Sarah Watson, Ryan Gray, Johnny Larenus, Unding Jami, Toby Marthews, Alexander Karolus, the Danum 50 ha plot team, Sylvester Tan, Xyxtus Tan, Nasir Muhi and Abilano Deres helped with the data collection. We thank Susan Page, Juan Carlos Berrio, Jörg Kaduk and Katie O’Brien for their constructive comments.Peer reviewedPublisher PD

    Assessing autophagy in archived tissue or how to capture autophagic flux from a tissue snapshot

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    Autophagy is a highly conserved degradation mechanism that is essential for maintaining cellular homeostasis. In human disease, autophagy pathways are frequently deregulated and there is immense interest in targeting autophagy for therapeutic approaches. Accordingly, there is a need to determine autophagic activity in human tissues, an endeavor that is hampered by the fact that autophagy is characterized by the flux of substrates whereas histology informs only about amounts and localization of substrates and regulators at a single timepoint. Despite this challenging task, considerable progress in establishing markers of autophagy has been made in recent years. The importance of establishing clear-cut autophagy markers that can be used for tissue analysis cannot be underestimated. In this review, we attempt to summarize known techniques to quantify autophagy in human tissue and their drawbacks. Furthermore, we provide some recommendations that should be taken into consideration to improve the reliability and the interpretation of autophagy biomarkers in human tissue samples.This work was supported by grants from the Bernese Cancer League, “Stiftung für klinisch-experimentelle Tumorforschung”, and the Werner and Hedy Berger-Janser Foundation for Cancer Research (to M.H.); by Institute of Health Carlos III (ISCIII) and FEDER funds from the EU (PI14/01085 and PI17/00093) and supported by Miguel Servet contract by ISCIII and FSE funds (CPII16/00023) (to M.M.); from the Spanish Ministry of Science, Innovation and Universities (RTI2018-096748-B-100 to N.A.); from the University Professor Training Fellowship, Ministry of Science, Innovation and University, Government of Spain (FPU17/00026) (to P.C.O); from the ISCIII (PI16/00090 and PI19/01266) and the Andalusian Government (Consejería de Igualdad, Salud y Políticas Sociales, PI-0198-2016) for their financial support, and from the Biomedical Research Network Center for Liver and Digestive Diseases (CIBERehd) founded by the ISCIII and co-financed by European Development Regional Fund (EDRF) “A way to achieve Europe” for their financial support (to J.M.), from Breakthrough Cancer Research, Ireland funding (to S.L.M); from the PI18/00442 grant integrated into the State Plan for R & D + I2013-2016 and funded by the ISCIII and the ERDF, a way to make Europe (to G.V.); from the Luxembourg National Research Fund (C18/BM/12670304/COMBATIC to B.J.); from the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, by the European Regional Development Fund (FEDER), through the Competitiveness Factors Operational Programme (COMPETE) (NORTE-01-0145-FEDER-000013) and from the projects POCI-01-0145-FEDER-028159 and POCI-01-0145-FEDER-030782 by FEDER, through the COMPETE (to P.L.); from National funds, through the Foundation for Science and Technology (FCT) (to P.L.); from ARRS—the Slovenian research agency, programme P1-0140: Proteolysis and its regulation (led by B. Turk) (to E.Ž.); from the Swiss Cancer Research (KFS-3360-02-2014) (to A.P, and M.P.T.) (KFS-3409-02-2014), and the Swiss National Science Foundation (31003A_173219) (to M.P.T.)

    Littoral macrobenthic communities and water quality in El Pañe Reservoir, Arequipa, Peru

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    High Andean ponds and reservoirs are among the least-studied environments. We evaluated the composition of littoral macrobenthos and how it is affected by the physicochemical conditions of the water in El Pañe reservoir (Peru), located at 4,550 m.a.s.l. Samples were taken between November 2017 and October 2018 from three zones in the reservoir: low (downstream), middle and high (upstream); two of these zones with fish farms (low and middle) and one zone without fish farms (high). The following physicochemical parameters of the water were measured: dissolved oxygen, conductivity, pH and temperature. The macrobenthic community was analysed through diversity indices such as Shannon-Wiener (H’), Simpson’s dominance index (D), Pielou’s evenness (J’), true diversity (D1), and richness (S). The influence of the physicochemical variables on the macrobenthos was estimated by canonical correspondence analysis (CCA) and non-metric multidimensional scaling (NMDS). Dissolved oxygen was found to have lower values (<0.5 mg/l) than specified in the Environmental Quality Standards (EQS). Macroinvertebrate richness for the whole reservoir was 17 families, and the family with highest relative abundance was Chironomidae (42.24% in the low zone, 51% in the middle zone and 40.43% in the high zone). The indices showed greater species richness in the high zone, where there are no fish farms. Dissolved oxygen and conductivity were the main factors determining macrobenthos distribution and composition.Facultad de Ciencias Naturales y Muse
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