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121.
In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean. 相似文献
122.
Elinor K Karlsson Snaevar Sigurdsson Emma Ivansson Rachael Thomas Ingegerd Elvers Jason Wright Cedric Howald Noriko Tonomura Michele Perloski Ross Swofford Tara Biagi Sarah Fryc Nathan Anderson Celine Courtay-Cahen Lisa Youell Sally L Ricketts Sarah Mandlebaum Patricio Rivera Henrik von Euler William C Kisseberth Cheryl A London Eric S Lander Guillermo Couto Kenine Comstock Mike P Starkey Jaime F Modiano Matthew Breen Kerstin Lindblad-Toh 《Genome biology》2013,14(12):1-16
Background
Canine osteosarcoma is clinically nearly identical to the human disease, but is common and highly heritable, making genetic dissection feasible.Results
Through genome-wide association analyses in three breeds (greyhounds, Rottweilers, and Irish wolfhounds), we identify 33 inherited risk loci explaining 55% to 85% of phenotype variance in each breed. The greyhound locus exhibiting the strongest association, located 150 kilobases upstream of the genes CDKN2A/B, is also the most rearranged locus in canine osteosarcoma tumors. The top germline candidate variant is found at a >90% frequency in Rottweilers and Irish wolfhounds, and alters an evolutionarily constrained element that we show has strong enhancer activity in human osteosarcoma cells. In all three breeds, osteosarcoma-associated loci and regions of reduced heterozygosity are enriched for genes in pathways connected to bone differentiation and growth. Several pathways, including one of genes regulated by miR124, are also enriched for somatic copy-number changes in tumors.Conclusions
Mapping a complex cancer in multiple dog breeds reveals a polygenic spectrum of germline risk factors pointing to specific pathways as drivers of disease. 相似文献123.
124.
125.
Intensive nitrogen loss over the Omani Shelf due to anammox coupled with dissimilatory nitrite reduction to ammonium 总被引:1,自引:0,他引:1
Marlene M Jensen Phyllis Lam Niels Peter Revsbech Birgit Nagel Birgit Gaye Mike SM Jetten Marcel MM Kuypers 《The ISME journal》2011,5(10):1660-1670
A combination of stable isotopes (15N) and molecular ecological approaches was used to investigate the vertical distribution and mechanisms of biological N2 production along a transect from the Omani coast to the central–northeastern (NE) Arabian Sea. The Arabian Sea harbors the thickest oxygen minimum zone (OMZ) in the world''s oceans, and is considered to be a major site of oceanic nitrogen (N) loss. Short (<48 h) anoxic incubations with 15N-labeled substrates and functional gene expression analyses showed that the anammox process was highly active, whereas denitrification was hardly detectable in the OMZ over the Omani shelf at least at the time of our sampling. Anammox was coupled with dissimilatory nitrite reduction to ammonium (DNRA), resulting in the production of double-15N-labeled N2 from 15NO2−, a signal often taken as the lone evidence for denitrification in the past. Although the central–NE Arabian Sea has conventionally been regarded as the primary N-loss region, low potential N-loss rates at sporadic depths were detected at best. N-loss activities in this region likely experience high spatiotemporal variabilities as linked to the availability of organic matter. Our finding of greater N-loss associated with the more productive Omani upwelling region is consistent with results from other major OMZs. The close reliance of anammox on DNRA also highlights the need to take into account the effects of coupling N-transformations on oceanic N-loss and subsequent N-balance estimates. 相似文献
126.
Simões T Charro N Blonder J Faria D Couto FM Chan KC Waybright T Isaaq HJ Veenstra TD Penque D 《Journal of Proteomics》2011,75(1):56-69
A comprehensive proteomic profiling of nasal epithelium (NE) is described. This study relies on simple subcellular fractionation used to obtain soluble- and membrane-enriched fractions followed by 2-dimensional liquid chromatography (2D-LC) separation and tandem mass spectrometry (MS/MS). The cells were collected using a brushing technique applied on NE of clinically evaluated volunteers. Subsequently, the soluble- and the membrane-protein enriched fractions were prepared and analyzed in parallel using 2D-LC-MS/MS. In a set of 1482 identified proteins, 947 (63.9%) proteins were found to be associated to membrane fraction. Grand average hydropathy value index (GRAVY) analysis, the transmembrane protein mapping and annotations of primary location deposited in the Human Protein Reference Database (HPRD) confirmed an enrichment of hydrophobic proteins on this dataset. Ingenuity Pathway Analysis (IPA) of soluble fraction revealed an enrichment of molecular and cellular functions associated with cell death, protein folding and drug metabolism while in membrane fraction showed an enrichment of functions associated with molecular transport, protein trafficking and cell-to-cell signaling and interaction. The IPA showed similar enrichment of functions associated with cellular growth and proliferation in both soluble and membrane subproteomes. This finding was in agreement with protein content analysis using exponentially modified protein abundance index (emPAI). A comparison of our data with previously published studies focusing on respiratory tract epithelium revealed similarities related to identification of proteins associated with physical barrier function and immunological defence. In summary, we extended the NE molecular profile by identifying and characterizing proteins associated to pivotal functions of a respiratory epithelium, including the control of fluid volume and ionic composition at the airways' surface, physical barrier maintenance, detoxification and immunological defence. The extent of similarities supports the applicability of a less invasive analysis of NE to assess prognosis and treatment response of lung diseases such as asthma, cystic fibrosis and chronic obstructive pulmonary disease. 相似文献
127.
Vanessa Silva-Moraes Flávia Fernanda Bubula Couto Marah Mileib Vasconcelos Neusa Araújo Paulo Marcos Zech Coelho Naftale Katz Rafaella Fortini Queiroz Grenfell 《Memórias do Instituto Oswaldo Cruz》2013,108(5):600-604
Current schistosomiasis control strategies are largely based on chemotherapeutic
agents and a limited number of drugs are available today. Praziquantel (PZQ) is
the only drug currently used in schistosomiasis control programs. Unfortunately,
this drug shows poor efficacy in patients during the earliest infection phases.
The effects of PZQ appear to operate on the voltage-operated Ca2+channels, which
are located on the external Schistosoma mansoni membrane.
Because some Ca2+channels have dihydropyridine drug class (a class that includes
nifedipine) sensitivity, an in vitro analysis using a calcium channel antagonist
(clinically used for cardiovascular hypertension) was performed to determine the
antischistosomal effects of nifedipine on schistosomula and adult worm cultures.
Nifedipine demonstrated antischistosomal activity against schistosomula and
significantly reduced viability at all of the concentrations used alone or in
combination with PZQ. In contrast, PZQ did not show significant efficacy when
used alone. Adult worms were also affected by nifedipine after a 24 h incubation
and exhibited impaired motility, several lesions on the tegument and intense
contractility. These data support the idea of Ca2+channels subunits as drug
targets and favour alternative therapeutic schemes when drug resistance has been
reported. In this paper, strong arguments encouraging drug research are
presented, with a focus on exploring schistosomal Ca2+channels. 相似文献
128.
Carlos Martins Luís F. Azevedo Orquídea Ribeiro Luísa Sá Paulo Santos Luciana Couto Altamiro Costa-Pereira Alberto P. Hespanhol 《PloS one》2013,8(11)
Background
Most of the strategies to induce a more rational use of preventive health services are oriented to the medical side of the doctor-patient relationship. However, the consultation model has changed, and patients now have a more important role in medical consultation. The aim of this study was to assess which healthcare services are deemed necessary, and with what frequency, by adults from the general Portuguese population.Methods
Design: Population-based nationwide cross-sectional study Setting: Portuguese population Participants: One thousand Portuguese adults, surveyed by computer-assisted telephone interviewing and selected by a stratified cluster sampling design. Measurements: Proportions and population prevalence estimates were determined for each healthcare service, taking into account whether respondents considered them necessary, and with what frequency.Results
Respondent ages ranged between 18 and 97 years, and 520 of 1000 (52%) respondents were women. Among Portuguese adults, 99.2% (95% confidence interval (CI): 98.5 to 99.6) believe that they should undergo general routine blood and urine tests, to be repeated every 12.0 months on average (95% CI: 11.4 to 12.6); 87.4% (95% CI: 85.3 to 89.3) of the respondents reported having actually performed these tests. Of the 15 services surveyed, 14 were considered periodically necessary by more than 60% of respondents. Among the respondents, 37.7% (95% CI: 34.5 to 41.1) reported using healthcare services by their own initiative.Conclusions
The majority of Portuguese adults believe that they should utilize a great number of healthcare services, on a nearly annual basis; most actually follow this schedule. Our findings indicate a tendency towards the overuse of resources.Adequate patient-oriented strategies regarding the use of medical tests and preventive interventions—with appropriate information and discussion of risks and harms—are urgently needed, and crucial for achieving a more rational use of healthcare services and for preventing the consequences of over-testing. 相似文献129.
Mark S. Johnson Eduardo Guimar?es Couto Osvaldo B. Pinto Jr Juliana Milesi Ricardo S. Santos Amorim Indira A. M. Messias Marcelo Sacardi Biudes 《PloS one》2013,8(6)
The Pantanal is a biodiversity hotspot comprised of a mosaic of landforms that differ in vegetative assemblages and flooding dynamics. Tree islands provide refuge for terrestrial fauna during the flooding period and are particularly important to the regional ecosystem structure. Little soil CO2 research has been conducted in this region. We evaluated soil CO2 dynamics in relation to primary controlling environmental parameters (soil temperature and soil water). Soil respiration was computed using the gradient method using in situ infrared gas analyzers to directly measure CO2 concentration within the soil profile. Due to the cost of the sensors and associated equipment, this study was unreplicated. Rather, we focus on the temporal relationships between soil CO2 efflux and related environmental parameters. Soil CO2 efflux during the study averaged 3.53 µmol CO2 m−2 s−1, and was equivalent to an annual soil respiration of 1220 g C m−2 y−1. This efflux value, integrated over a year, is comparable to soil C stocks for 0–20 cm. Soil water potential was the measured parameter most strongly associated with soil CO2 concentrations, with high CO2 values observed only once soil water potential at the 10 cm depth approached zero. This relationship was exhibited across a spectrum of timescales and was found to be significant at a daily timescale across all seasons using conditional nonparametric spectral Granger causality analysis. Hydrology plays a significant role in controlling CO2 efflux from the tree island soil, with soil CO2 dynamics differing by wetting mechanism. During the wet-up period, direct precipitation infiltrates soil from above and results in pulses of CO2 efflux from soil. The annual flood arrives later, and saturates soil from below. While CO2 concentrations in soil grew very high under both wetting mechanisms, the change in soil CO2 efflux was only significant when soils were wet from above. 相似文献
130.
Thas S. Franceschi Mayara S. P. Soares Nathalia S. Pedra Natlia P. Bona Luiza Spohr Fernanda C. Teixeira Carlus A. T. do Couto Roselia M. Spanevello Marion Deon Carmen R. Vargas Elizandra Braganhol Francieli M. Stefanello 《Amino acids》2020,52(4):629-638
Hypermethioninemia is a disorder characterized by high plasma levels of methionine (Met) and its metabolites such as methionine sulfoxide (MetO). Studies have reported associated inflammatory complications, but the mechanisms involved in the pathophysiology of hypermethioninemia are still uncertain. The present study aims to evaluate the effect of chronic administration of Met and/or MetO on phenotypic characteristics of macrophages, in addition to oxidative stress, purinergic system, and inflammatory mediators in macrophages. In this study, Swiss male mice were subcutaneously injected with Met and MetO at concentrations of 0.35–1.2 g/kg body weight and 0.09–0.3 g/kg body weight, respectively, from the 10th–38th day post-birth, while the control group was treated with saline solution. The results revealed that Met and/or MetO induce an M1/classical activation phenotype associated with increased levels of tumor necrosis factor alpha and nitrite, and reduced arginase activity. It was also found that Met and/or MetO alter the activity of antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase, as well as the levels of thiol and reactive oxygen species in macrophages. The chronic administration of Met and/or MetO also promotes alteration in the hydrolysis of ATP and ADP, as indicated by the increased activity of ectonucleotidases. These results demonstrate that chronic administration of Met and/or MetO promotes activated pro-inflammatory profile by inducing M1/classical macrophage polarization. Thus, the changes in redox status and purinergic system upon chronic Met and/or MetO exposure may contribute towards better understanding of the alterations consistent with hypermethioninemic patients. 相似文献