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21.
Heteronarce rierai sp. nov. is described on the basis of six specimens, one male and five females, caught in the waters off Mozambique (western
Indian Ocean). Total lengths range from 257 to 296 mm. The new species is distinguished from the three other species of the
genusHeteronarce by its narrower disc width (29.6% of TL in male, and 33.0 to 39.2% of TL in females), shorter disc length (32.7% of TL in
male, and 34.4 to 40.6% of TL in females), and its longer interdorsal distance (10.1 to 11.7% of TL). 相似文献
22.
Vanessa Miguel Domingo Balbi Cecilia Castillo Raimundo Villegas 《The Journal of membrane biology》1992,129(1):37-47
Phosphatidylcholine (PC) alone or with phosphatidylethanolamine (PE) are sufficient for the reconstitution of Na+ channels in planar lipid bilayers. However, when Na+ channels were first reconstituted into liposomes using the freeze-thaw-sonication method, addition of acidic phospholipids, such as phosphatidylserine (PS), to the neutral phospholipids was necessary to obtain a significant toxin-modulated 22Na uptake. To further investigate the acidic phospholipid effect on reconstitution into liposomes, Na+ channels purified from Electrophorus electricus electrocytes were reconstituted into liposomes of different composition by freeze-thaw sonication and the effect of batrachotoxin and tetrodotoxin on the 22Na flux was measured. The results revealed that, under our experimental conditions, the presence of an acidic phospholipid was also necessary to obtain a significant neurotoxin-modulated 22Na influx. Though neurotoxin-modulated 22Na fluxes have been reported in proteoliposomes made with purified Na+ channels and PC alone, the 22Na fluxes were smaller than those found using lipid mixtures containing acidic phospholipids. Electron microscopy of negatively stained proteoliposomes prepared with PC, PC/PS (1:1 molar ratio), and PS revealed that the acidic phospholipid increases the size of the reconstituted proteoliposomes. The increment in size caused by the acidic phospholipid, due to the associated increase in internal volume for 22Na uptake and in area for Na+ channel incorporation, appears to be responsible for the large neurotoxin-modulated 22Na fluxes observed. 相似文献
23.
24.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs. 相似文献
25.
Nucleotide sequence heterogeneity of the RNA from a natural population of foot-and-mouth-disease virus 总被引:30,自引:0,他引:30
The genomic RNA from isolates of foot-and-mouth-disease virus (FMDV) of serological types O or C obtained during epizootic outbreaks have been analysed by two-dimensional gel electrophoresis of the T1 RNase-generated oligonucleotides (T1 fingerprinting). Among virus isolates that are closely related serologically, 4-12 oligonucleotide changes were detected constitute the genome, the variations affect 0.7%-2.2% positions in FMDV RNA. Higher nucleotide-sequence divergence exists between the genomic RNAs from serologically unrelated viruses, while a 100-fold lower RNA sequence heterogeneity has been detected by analysis of individual clones derived from one viral isolate. Oligonucleotide mapping indicates that the variant oligonucleotides are scattered throughout the FMDV genome. We suggest that extensive genetic variability at many RNA sites is the basis for the antigenic diversity of FMDV. 相似文献
26.
This microreview focuses on the nucleophilic ring‐opening of azetidiniums presenting various substitution patterns at C2, C3, and C4. In most cases, the nucleophilic ring‐opening occurred in a stereoselective and regioselective fashion producing functionalized linear amines. Experimental selectivities associated with Density Functional Theory (DFT) calculations have allowed a better understanding of the parameters governing the regioselectivities. 相似文献
27.
28.
Teresa M. Zotes Roberto Spada Vladimir Mulens Sonia Pérez-Yagüe Carlos O. Sorzano Klaus Okkenhaug Ana C. Carrera Domingo F. Barber 《PloS one》2013,8(8)
The role of p110δ PI3K in lymphoid cells has been studied extensively, showing its importance in immune cell differentiation, activation and development. Altered T cell localization in p110δ-deficient mouse spleen suggested a role for p110δ in non-hematopoietic stromal cells, which maintain hematopoietic cell segregation. We tested this hypothesis using p110δWT/WT mouse bone marrow to reconstitute lethally irradiated p110δWT/WT or p110δD910A/D910A (which express catalytically inactive p110δ) recipients, and studied localization, number and percentage of hematopoietic cell subsets in spleen and lymph nodes, in homeostatic conditions and after antigen stimulation. These analyses showed diffuse T cell areas in p110δD910A/D910A and in reconstituted p110δD910A/D910A mice in homeostatic conditions. In these mice, spleen CD4+ and CD8+ T cell numbers did not increase in response to antigen, suggesting that a p110δD910A/D910A stroma defect impedes correct T cell response. FACS analysis of spleen stromal cell populations showed a decrease in the percentage of gp38−CD31+ cells in p110δD910A/D910A mice. qRT-PCR studies detected p110δ mRNA expression in p110δWT/WT spleen gp38−CD31+ and gp38+CD31+ subsets, which was reduced in p110δD910A/D910A spleen. Lack of p110δ activity in these cell populations correlated with lower LTβR, CCL19 and CCL21 mRNA levels; these molecules participate in T cell localization to specific spleen areas. Our results could explain the lower T cell numbers and more diffuse T cell areas found in p110δD910A/D910A mouse spleen, as well as the lower T cell expansion after antigen stimulation in p110δD910A/D910A compared with p110δWT/WT mice. 相似文献
29.
José R. Santos José A. Mu?oz-Moreno José Moltó Anna Prats Adrià Curran Pere Domingo Josep M. Llibre Daniel R. McClernon Isabel Bravo Jaume Canet Victoria Watson David Back Bonaventura Clotet 《PloS one》2013,8(7)
Background
Data on suppression of HIV replication in the CNS and on the subsequent risk of neurocognitive impairment using monotherapy with boosted protease inhibitors are limited.Methods
Ours was an exploratory cross-sectional study in patients on lopinavir/ritonavir-based monotherapy (LPV/r-MT) or standard triple therapy (LPV/r-ART) for at least 96 weeks who maintained a plasma viral load <50 copies/mL. HIV-1 RNA in CSF was determined by HIV-1 SuperLow assay (lower limit of detection, 1 copy/mL). Neurocognitive functioning was assessed using a recommended battery of neuropsychological tests covering 7 areas. Neurocognitive impairment (NCI) was determined and also a global deficit score (GDS) for study comparisons.Results
Seventeen patients on LPV/r-MT and 17 on LPV/r-ART were included. Fourteen (82.4%) patients on LPV/r-MT and 16 (94.1%) on LPV/r-ART had HIV-1 RNA <1 copy/mL in CSF (p = 0.601). NCI was observed in 7 patients on LPV/r-MT and in 10 on LPV/r-ART (41% vs 59%; p = 0.494). Mean (SD) GDS was 0.22 (0.20) in patients on LPV/r-MT and 0.47 (0.34) in those on LPV/r-ART (p = 0.012).Conclusions
Suppression of HIV in CSF is similar in individuals with durable plasma HIV-1 RNA suppression who are receiving LPV/r-MT or LPV/r-ART for at least 96 weeks. Findings for HIV-1 replication in CSF and neurocognitive status indicate that this strategy seems to be safe for CNS functioning. 相似文献30.
Tadeo Ramirez-Parada Domingo Cabrera Zoe Diaz-Martin Luke Browne Jordan Karubian 《Biotropica》2020,52(5):845-856
Many tropical plant species show wide intra-population variation in reproductive timing, resulting in the protracted presence of flowering and fruiting individuals. Various eco-evolutionary drivers have been proposed as ultimate causes for asynchronous phenology, yet little is known about the proximate factors that control reproductive onset among individuals or that influence the proportion of trees producing new inflorescences within a population. We employed a nine-year phenological record from 178 individuals of the hyperdominant, asynchronously flowering canopy palm, Oenocarpus bataua (Arecaceae)¸ to assess whether resource-related variables influence individual- and population-level flowering phenology. Among individuals, access to sunlight increased rates of inflorescence production, while the presence of resource sinks related to current investment in reproduction—developing infructescences—reduced the probability of producing new inflorescences. At the population level, climate anomalies induced by El Niño Southern Oscillation (ENSO) affected the proportion of the population producing inflorescences through time. Moreover, the effects of ENSO anomalies on flowering patterns depended on the prevalence of developing infructescences in the population, with stronger effects in periods of low developing-infructescence frequency. Taken together, these results suggest that resource-related variables can drive phenological differences among individuals and mediate population-level responses to larger-scale variables, such as climate anomalies. Consequently, a greater focus on the role of resource levels as endogenous cues for reproduction might help explain the frequent aseasonal phenological patterns observed among tropical plants, particularly those showing high intra-population asynchrony. 相似文献