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961.
Mass culture of benthic macroalgae under rough offshore conditions in the North Sea requires rigid culture support systems that cannot only withstand rough weather conditions but can also be effectively handled while at the same time retain the cultured species. Various carrier constructions and different mooring systems were tested. Laminaria saccharina grew on all of these carriers with initially high (up to 14.5% per day) and later decreasing length increments. Longlines, ladder and grid systems had certain disadvantages and these are discussed. The study results led to a new ring carrier (patent pending), first used in 1994/1995, which was gradually improved until 2002. This system now emerges as being superior, since it resists not only rough weather conditions (2 m s–1 current velocity, 6 m wave height) but also permits ease of handling when compared to other constructions. The ring allows various operational modes and can be equipped with culture lines that can be collected offshore or transported to shore facilities for harvesting. The modular nature of the tested ring system lends itself for future use in integrated aquaculture systems located in or attached to offshore wind farms. 相似文献
962.
Beringue V Vilette D Mallinson G Archer F Kaisar M Tayebi M Jackson GS Clarke AR Laude H Collinge J Hawke S 《The Journal of biological chemistry》2004,279(38):39671-39676
Conversion of the cellular alpha-helical prion protein (PrP(C)) into a disease-associated isoform (PrP(Sc)) is central to the pathogenesis of prion diseases. Molecules targeting either normal or disease-associated isoforms may be of therapeutic interest, and the antibodies binding PrP(C) have been shown to inhibit prion accumulation in vitro. Here we investigate whether antibodies that additionally target disease-associated isoforms such as PrP(Sc) inhibit prion replication in ovine PrP-inducible scrapie-infected Rov cells. We conclude from these experiments that antibodies exclusively binding PrP(C) were relatively inefficient inhibitors of ScRov cell PrP(Sc) accumulation compared with antibodies that additionally targeted disease-associated PrP isoforms. Although the mechanism by which these monoclonal antibodies inhibit prion replication is unclear, some of the data suggest that antibodies might actively increase PrP(Sc) turnover. Thus antibodies that bind to both normal and disease-associated isoforms represent very promising anti-prion agents. 相似文献
963.
While pancreatic protein synthesis and the initiation of translation are regulated by hormones and neurotransmiters, whether the elongation process is also regulated is unknown. Stimulatory doses of cholecystokinin (CCK) (100 pM), bombesin (10 nM), and carbachol (10 microM) increased elongation rates (measured as ribosomal half-transit time) in pancreatic acini in vitro. At the same time these secretagogues reduced elongation factor 2 (eEF2) phosphorylation, the main factor known to regulate elongation, and increased the phosphorylation of the eEF2 kinase. The mTOR inhibitor rapamycin reversed the dephosphorylation of eEF2 induced by CCK, as did treatment with the p38 MAPK inhibitor SB202190, the MEK inhibitor PD98059, and the phosphatase inhibitor calyculin A. Neither rapamycin, SB202190, PD98059 nor calyculin A had an effect on CCK mediated eEF2 kinase phosphorylation. Translation elongation in pancreatic acinar cells is likely regulated by eEF2 through the mTOR, p38, and MEK pathways, and modulated through PP2A. 相似文献
964.
Cristina M ximo Manuela Lageiro Ana Duarte Alberto Reis Maria Costa-Ferreira 《Biocatalysis and Biotransformation》2004,22(5):307-313
Decolourisation of the azo dye Reactive Black 5 by Geotrichum sp. CCMI 1019 was studied using stirred tank reactors (STR) and two types of bubble columns (porous plate (PP) bubble column and aeration tube (AT) bubble column). For the bubble columns, the kLa increased with the gas fractional hold-up (εG) and the aeration rate. A linear relationship between εG and superficial gas velocity was obtained for all reactors. At same aeration rates, the PP bubble columns showed higher kLa and hold-up values than the AT bubble column. In the STRs, large and dense aggregates were formed which adhered to surfaces whereas bubble columns gave smaller and less compact pellets.
Manganese peroxidase and laccase were detected in the extracellular media in all reactors. However, laccase was only detected after the onset of decolourisation, suggesting that additional enzymes may be involved. Mn peroxidase activity was detected (about 46 U/ml) in both the STRs and AT bubble columns but higher values (110 U/ml) were obtained with the PP bubble columns.
Out of the three reactor systems studied, the AT bubble columns gave the most favourable results for Reactive Black 5 decolourisation. Rapid and complete colour removal was obtained throughout the visible spectrum. Bubble columns are simple in design as well as operation and may be useful for the bioremediation of textile wastewater. 相似文献
Manganese peroxidase and laccase were detected in the extracellular media in all reactors. However, laccase was only detected after the onset of decolourisation, suggesting that additional enzymes may be involved. Mn peroxidase activity was detected (about 46 U/ml) in both the STRs and AT bubble columns but higher values (110 U/ml) were obtained with the PP bubble columns.
Out of the three reactor systems studied, the AT bubble columns gave the most favourable results for Reactive Black 5 decolourisation. Rapid and complete colour removal was obtained throughout the visible spectrum. Bubble columns are simple in design as well as operation and may be useful for the bioremediation of textile wastewater. 相似文献
965.
Maria Vivian?Camacho Gragedadh@stcc.nagasaki-u.ac.jp" title="MVCG dh@stcc.nagasaki-u.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Yoshitaka?Sakakura Atsushi?Hagiwara 《Ichthyological Research》2004,51(4):309-315
The mangrove killifish Rivulus marmoratus was reared at 25°±1°C and 17ppt salinity from 0 to 100 days after hatching (DAH), and its early development was described by examining growth and morphometric parameters, meristic characters (vertebral and fin-ray counts), bone-cartilage development, and pigmentation. Growth was isometric for preanal length, head length, snout length, body depth, pectoral-fin length, dorsal-fin length, anal-fin length, and caudal-peduncle depth. Negative allometric growth was observed in eye diameter and gape size. Meristic counts (mean±SD) for vertebrae (34.2±0.4) and dorsal- (8.6±0.5), anal- (11.4±0.5), and caudal-fin rays (30.2±0.8) were complete at 0 DAH (n=5), whereas pectoral-fin rays and pelvic-fin rays were complete by 30 DAH (14.5±0.4, n=5) and 60 DAH (4.2±0.8, n=5). Full ossification of meristic elements proceeded in the following sequence: vertebrae (by 30 DAH), caudal-, dorsal-, and anal-fin rays (by 60 DAH), pectoral-fin rays (between 60 DAH and 100 DAH), and pelvic-fin rays (by 100 DAH). Both morphological characters and meristic counts indicate that this species can be considered to be a juvenile after 9.8mm in standard length (20 DAH). 相似文献
966.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
967.
Alexandre Grangeiro Maria Mercedes Escuder Alex Jones Flores Cassanote Rosa Alencar Souza Artur O. Kalichman Valdiléa Veloso Maria Letícia Rodrigues Ikeda Nêmora Tregnago Barcellos Carlos Brites Unai Tupinanbás Noaldo O. Lucena Carlos Lima da Silva Heloisa Ramos Lacerda Beatriz Grinsztejn Euclides Ayres Castilho 《PloS one》2014,9(5)
Background
The HIV-Brazil Cohort Study was established to analyze the effectiveness of combination antiretroviral therapy (cART) and the impact of this treatment on morbidity, quality of life (QOL) and mortality. The study design, patients’ profiles and characteristics of cART initiation between 2003 and 2010 were described.Methodology/Principal Findings
Since 2003, the HIV-Brazil Cohort has been following HIV-infected adults receiving cART at 26 public health care facilities, using routine clinical care data and self-reported QOL questionnaires. When not otherwise available, data are obtained from national information systems. The main outcomes of interest are diseases related or unrelated to HIV; suppression of viral replication; adverse events; virological, clinical and immunological failures; changes in the cART; and mortality. For the 5,061 patients who started cART between 2003 and 2010, the median follow-up time was 4.1 years (IQR 2.2–5.9 years) with an 83.4% retention rate. Patient profiles were characterized by a predominance of men (male/female ratio 1.7∶1), with a mean age of 36.9 years (SD 9.9 years); 55.2% had been infected with HIV via heterosexual contact. The majority of patients (53.4%) initiated cART with a CD4+ T-cell count ≤200 cells/mm3. The medications most often used in the various treatment regimens were efavirenz (59.7%) and lopinavir/ritonavir (18.2%). The proportion of individuals achieving viral suppression within the first 12 months of cART use was 77.4% (95% CI 76.1–78.6). Nearly half (45.4%) of the patients presented HIV-related clinical manifestations after starting cART, and the AIDS mortality rate was 13.9 per 1,000 person-years.Conclusions/Significance
Results from cART use in the daily practice of health services remain relatively unknown in low- and middle-income countries, and studies with the characteristics of the HIV-Brazil Cohort contribute to minimizing these shortcomings, given its scope and patient profile, which is similar to that of the AIDS epidemic in the country. 相似文献968.
Nágilla Daliane Feliciano Vanessa da Silva Ribeiro Fabiana de Almeida Araújo Santos Patricia Tiemi Fujimura Henrique Tomaz Gonzaga Luiz Ricardo Goulart Julia Maria Costa-Cruz 《PLoS neglected tropical diseases》2014,8(5)
Background
Strongyloidiasis, a human intestinal infection caused by the nematode Strongyloides stercoralis, is frequently underdiagnosed and although its high prevalence is still a neglected parasitic disease because conventional diagnostic tests based on parasitological examination (presence of Strongyloides larvae in stool) are not sufficiently sensitive due to the low parasitic load and to the irregular larval output. There is an urgent need to improve diagnostic assays, especially for immunocompromised patients with high parasitic load as consequence of self-infection cycle, which can disseminate throughout the body, resulting in a potentially fatal hyperinfection syndrome often accompanied by sepsis or meningitis.Methods/Principal Findings
We have performed Phage Display technology to select peptides that mimic S. stercoralis antigens, capable of detecting a humoral response in patients with strongyloidiasis. The peptides reactivity was investigated by Phage-ELISA through different panels of serum samples. We have successfully selected five peptides with significant immunoreactivity to circulating IgG from patients'' sera with strongyloidiasis. The phage displayed peptides C9 and C10 presented the highest diagnostic potential (AUC>0.87) with excellent sensitivity (>85%) and good specificity (>77.5%), suggesting that some S. stercoralis antigens trigger systemic immune response.Conclusions/Significance
These novel antigens are interesting serum biomarkers for routine strongyloidiasis screenings due to the easy production and simple assay using Phage-ELISA. Such markers may also present a promising application for therapeutic monitoring. 相似文献969.
Erika dos Santos Silva Cínthia Bruno de Abreu Tereza Cristina Orlando Célio Wisniewski Maria José dos Santos-Wisniewski 《PloS one》2014,9(5)
Knowledge of reproductive rates and life cycle of the Cladocera species is essential for population dynamic studies, secondary production and food webs, as well as the management and preservation of aquatic ecosystems. The present study aimed to understand the life cycle and growth of Alona iheringula Kotov & Sinev, 2004 (Crustacea, Anomopoda, Chydoridae), a Neotropical species, as well as its DNA barcoding, providing new information on the Aloninae taxonomy. The specimens were collected in the dammed portion of the Cabo Verde River (21°26′05″ S and 46°10′57″ W), in the Furnas Reservoir, Minas Gerais State, Brazil. Forty neonates were observed individually two or three times a day under controlled temperature (25±1°C), photoperiod (12 h light/12 h dark) and feeding (Pseudokirchneriella subcapitata at a concentration of 105 cells.mL−1 and a mixed suspension of yeast and fish feed in equal proportion). Individual body growth was measured daily under optical microscope using a micrometric grid and 40× magnification. The species had a mean size of 413(±29) µm, a maximum size of 510 µm and reached maturity at 3.24(±0.69) days of age. Mean fecundity was 2 eggs per female per brood and the mean number of eggs produced per female during the entire life cycle was 47.6(±6.3) eggs per female. The embryonic development time was 1.79(±0.23) days and the maximum longevity was 54 days. The species had eight instars throughout its life cycle and four instars between neonate and primipara stage. The present study using molecular data (a 461 bp smaller COI fragment) demonstrated a deep divergence in the Aloninae subfamily. 相似文献
970.
Rosa Luisi Elisabetta Panza Vincenzo Barrese Fabio Arturo Iannotti† Davide Viggiano† Agnese Secondo Lorella Maria Teresa Canzoniero Maria Martire‡ Lucio Annunziato Maurizio Taglialatela† 《Journal of neurochemistry》2009,109(1):168-181
In this study, the functional consequences of the pharmacological modulation of the M‐current (IKM) on cytoplasmic Ca2+ intracellular Ca2+concentration ([Ca2+]i) changes and excitatory neurotransmitter release triggered by various stimuli from isolated rat cortical synaptosomes have been investigated. Kv7.2 immunoreactivity was identified in pre‐synaptic elements in cortical slices and isolated glutamatergic cortical synaptosomes. In cerebrocortical synaptosomes exposed to 20 mM [K+]e, the IKM activator retigabine (RT, 10 μM) inhibited [3H]d ‐aspartate ([3H]d ‐Asp) release and caused membrane hyperpolarization; both these effects were prevented by the IKM blocker XE‐991 (20 μM). The IKM activators RT (0.1–30 μM), flupirtine (10 μM) and BMS‐204352 (10 μM) inhibited 20 mM [K+]e‐induced synaptosomal [Ca2+]i increases; XE‐991 (20 μM) abolished RT‐induced inhibition of depolarization‐triggered [Ca2+]i transients. The P/Q‐type voltage‐sensitive Ca2+channel (VSCC) blocker ω‐agatoxin IVA prevented RT‐induced inhibition of depolarization‐induced [Ca2+]i increase and [3H]d ‐Asp release, whereas the N‐type blocker ω‐conotoxin GVIA failed to do so. Finally, 10 μM RT did not modify the increase of [Ca2+]i and the resulting enhancement of [3H]d ‐Asp release induced by [Ca2+]i mobilization from intracellular stores, or by store‐operated Ca2+channel activation. Collectively, the present data reveal that the pharmacological activation of IKM regulates depolarization‐induced [3H]d ‐Asp release from cerebrocortical synaptosomes by selectively controlling the changes of [Ca2+]i occurring through P/Q‐type VSCCs. 相似文献