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221.
The novel 4,6-di-O-acetyl-2,3-dideoxy-D-erythro-hex-2-enopyranosyl sulfamide, which exhibits selectivity for inhibiting isoform IX of carbonic anhydrase as overexpressed in many tumors, has been investigated from a combined theoretical and spectroscopic point of view. The conformational study of the compound shows that the α-anomeric form is more stable than the β-anomeric form from a thermodynamic point of view after including solvent effects. This fact suggests that the synthesis reaction could take place mainly under thermodynamic control as the main experimental product is the α-anomeric form of the sulfamide. Calculated α/β ratio is about 95:5, in excellent agreement with experimental data. Optimized geometries of the α-anomeric form agree quite well with crystallographic data. The inclusion of a solvent has negligible effects on the conformations. A detailed analysis of some geometric parameters shed light into the conformational behavior of the sulfamide in terms of both exo- and endo-anomeric effects and antiperiplanar relationships. Natural bond orbital calculations confirm those findings. Several intramolecular hydrogen bonds, characterized through the Atoms-in-Molecules theory, were found in the stable conformers. They, however, seem to play no relevant role in determining the relative stability of α conformers with respect to the β ones. Calculated (1)H and (13)C NMR chemical shifts support previous findings concerning configuration and conformation assignments of the title sulfamide. The IR spectrum of the compound is recorded and reported for the first time and the assignment of some of the most important bands is accomplished with the aid of calculated harmonic vibrational frequencies.  相似文献   
222.
Fruit ripening in Prunus persica involves a number of physiological changes, being one of the most significant the mesocarp softening in melting varieties. In order to get a better understanding of the molecular processes involved in this phenomenon, the protein accumulation patterns in firm and soft fruit of three peach and two nectarine melting flesh varieties were assessed using 2D gel analysis. A General Linear Model (GLM) two-way analysis of variance determined that 164 of the 621 protein spots analyzed displayed a differential accumulation associated with the softening process. Among them, only 14 proteins changed their accumulation in all the varieties assessed, including proteins mostly involved in carbohydrates and cell wall metabolism as well as fruit senescence. The analysis among varieties showed that 195 and 189 spots changed within the firm and soft fruit conditions, respectively. Despite the changes in relative abundance in the spot proteins, the proteome is conserved among varieties and during the transition from firm to soft fruit. Only two spots proteins exhibited a qualitative change in all the conditions assessed. These results are in agreement with the notion that Prunus persica commercial varieties have a narrow genetic background.  相似文献   
223.
The aim of this study was to investigate the role of TLR2, TLR4 and MyD88 in sepsis-induced AKI. C57BL/6 TLR2(-/-), TLR4(-/-) and MyD88(-/-) male mice were subjected to sepsis by cecal ligation and puncture (CLP). Twenty four hours later, kidney tissue and blood samples were collected for analysis. The TLR2(-/-), TLR4(-/-) and MyD88(-/-) mice that were subjected to CLP had preserved renal morphology, and fewer areas of hypoxia and apoptosis compared with the wild-type C57BL/6 mice (WT). MyD88(-/-) mice were completely protected compared with the WT mice. We also observed reduced expression of proinflammatory cytokines in the kidneys of the knockout mice compared with those of the WT mice and subsequent inhibition of increased vascular permeability in the kidneys of the knockout mice. The WT mice had increased GR1(+low) cells migration compared with the knockout mice and decreased in GR1(+high) cells migration into the peritoneal cavity. The TLR2(-/-), TLR4(-/-), and MyD88(-/-) mice had lower neutrophil infiltration in the kidneys. Depletion of neutrophils in the WT mice led to protection of renal function and less inflammation in the kidneys of these mice. Innate immunity participates in polymicrobial sepsis-induced AKI, mainly through the MyD88 pathway, by leading to an increased migration of neutrophils to the kidney, increased production of proinflammatory cytokines, vascular permeability, hypoxia and apoptosis of tubular cells.  相似文献   
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225.
Tests of the biodiversity and ecosystem functioning (BEF) relationship have focused little attention on the importance of interactions between species diversity and other attributes of ecological communities such as community biomass. Moreover, BEF research has been mainly derived from studies measuring a single ecosystem process that often represents resource consumption within a given habitat. Focus on single processes has prevented us from exploring the characteristics of ecosystem processes that can be critical in helping us to identify how novel pathways throughout BEF mechanisms may operate. Here, we investigated whether and how the effects of biodiversity mediated by non-trophic interactions among benthic bioturbator species vary according to community biomass and ecosystem processes. We hypothesized that (1) bioturbator biomass and species richness interact to affect the rates of benthic nutrient regeneration [dissolved inorganic nitrogen (DIN) and total dissolved phosphorus (TDP)] and consequently bacterioplankton production (BP) and that (2) the complementarity effects of diversity will be stronger on BP than on nutrient regeneration because the former represents a more integrative process that can be mediated by multivariate nutrient complementarity. We show that the effects of bioturbator diversity on nutrient regeneration increased BP via multivariate nutrient complementarity. Consistent with our prediction, the complementarity effects were significantly stronger on BP than on DIN and TDP. The effects of the biomass-species richness interaction on complementarity varied among the individual processes, but the aggregated measures of complementarity over all ecosystem processes were significantly higher at the highest community biomass level. Our results suggest that the complementarity effects of biodiversity can be stronger on more integrative ecosystem processes, which integrate subsidiary “simpler” processes, via multivariate complementarity. In addition, reductions in community biomass may decrease the strength of interspecific interactions so that the enhanced effects of biodiversity on ecosystem processes can disappear well before species become extinct.  相似文献   
226.

Background

Over the last century the incidence of cutaneous melanoma has increased worldwide, a trend that has also been observed in Brazil. The identified risk factors for melanoma include the pattern of sun exposure, family history, and certain phenotypic features. In addition, the incidence of melanoma might be influenced by ethnicity. Like many countries, Brazil has high immigration rates and consequently a heterogenous population. However, Brazil is unique among such countries in that the ethnic heterogeneity of its population is primarily attributable to admixture. This study aimed to evaluate the contribution of European ethnicity to the risk of cutaneous melanoma in Brazil.

Methodology/Principal Findings

We carried out a hospital-based case-control study in the metropolitan area of Sao Paulo, Brazil. We evaluated 424 hospitalized patients (202 melanoma patients and 222 control patients) regarding phenotypic features, sun exposure, and number of grandparents born in Europe. Through multivariate logistic regression analysis, we found the following variables to be independently associated with melanoma: grandparents born in Europe—Spain (OR = 3.01, 95% CI: 1.03–8.77), Italy (OR = 3.47, 95% CI: 1.41–8.57), a Germanic/Slavic country (OR = 3.06, 95% CI: 1.05–8.93), or ≥2 European countries (OR = 2.82, 95% CI: 1.06–7.47); eye color—light brown (OR = 1.99, 95% CI: 1.14–3.84) and green/blue (OR = 4.62; 95% CI 2.22–9.58); pigmented lesion removal (OR = 3.78; 95% CI: 2.21–6.49); no lifetime sunscreen use (OR = 3.08; 95% CI: 1.03–9.22); and lifetime severe sunburn (OR = 1.81; 95% CI: 1.03–3.19).

Conclusions

Our results indicate that European ancestry is a risk factor for cutaneous melanoma. Such risk appears to be related not only to skin type, eye color, and tanning capacity but also to others specific characteristics of European populations introduced in the New World by European immigrants.  相似文献   
227.
Environmental manganese (Mn) toxicity causes an extrapyramidal, parkinsonian-type movement disorder with characteristic magnetic resonance images of Mn accumulation in the basal ganglia. We have recently reported a suspected autosomal recessively inherited syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia in cases without environmental Mn exposure. Whole-genome mapping of two consanguineous families identified SLC30A10 as the affected gene in this inherited type of hypermanganesemia. This gene was subsequently sequenced in eight families, and homozygous sequence changes were identified in all affected individuals. The function of the wild-type protein and the effect of sequence changes were studied in the manganese-sensitive yeast strain Δpmr1. Expressing human wild-type SLC30A10 in the Δpmr1 yeast strain rescued growth in high Mn conditions, confirming its role in Mn transport. The presence of missense (c.266T>C [p.Leu89Pro]) and nonsense (c.585del [p.Thr196Profs17]) mutations in SLC30A10 failed to restore Mn resistance. Previously, SLC30A10 had been presumed to be a zinc transporter. However, this work has confirmed that SLC30A10 functions as a Mn transporter in humans that, when defective, causes Mn accumulation in liver and brain. This is an important step toward understanding Mn transport and its role in neurodegenerative processes.  相似文献   
228.

Background

Although Morbillivirus and Toxoplasma gondii have emerged as important pathogens for several cetaceans populations over the last 20 years, they have never been identified together in a Mysticete. In particular, morbilliviral infection has been never described in the Mediterranean fin whale population.

Case presentation

On January 2011 an adult male of fin whale (Balaenoptera physalus) stranded along the Tyrrhenian coastline of Italy. During necropsy, tissue samples from heart, skeletal muscle, mesenteric lymph nodes, liver, spleen, lung, and kidney were collected and subsequently analyzed for Morbillivirus and Toxoplasma gondii by microscopic and molecular methods. Following the detailed necropsy carried out on this whale, molecular analysis revealed, for the first time, the simultaneous presence of a Dolphin Morbillivirus (DMV) and T. gondii infection coexisting with each other, along with high organochlorine pollutant concentrations, with special reference to DDT.

Conclusion

This report, besides confirming the possibility for Mysticetes to be infected with DMV, highlights the risk of toxoplasmosis in sea water for mammals, already immunodepressed by concurrent factors as infections and environmental contaminants.  相似文献   
229.
230.
Tropical rain forest dominated by Peltogyne gracilipes (Fabaceae) occurs on Maracá Island, Roraima, Brazil, on a range of soil types. Three forest types were stratified for sampling, according to the occurrence of Peltogyne trees: (1) Peltogyne-rich forest (PRF), (2) Peltogyne-poor forest (PPF), and (3) forest without Peltogyne (FWP). Biomass increment and change in total stand biomass were calculated from mortality, recruitment, and growth data for trees in the three forest types. Data were derived from permanent plots established in 1991, where all trees (≥10 cm diameter at breast height), including palms and vines (lianas), were tagged and measured in three plots, each of 0.25 ha, in each of the three forest types. Field surveys were carried out in October 1991 and March 2003. Over a period of 11 years, the above-ground biomass in all forest types declined slightly (<5%), associated with the death of large trees, especially in the monodominant forests (PRF and PPF). Within the study period, the forest on Maracá experienced two heavy droughts, related to El Niño events (1997–1998 and 2002–2003) and most mortality and loss of biomass probably occurred during these events. Therefore, as the Maracá forests appear not be increasing in above-ground biomass overall, they may not be acting as a sink for atmospheric CO2. The trees of the five most abundant species (Ecclinusa, Lecythis, Licania, Peltogyne, and Pradosia) accounted for about 55% of the total biomass in both FWP and PPF and for 74% in PRF. Peltogyne gracilipes had a stable, regenerating population in PRF, and is clearly a persistent dominant in a monodominant forest.  相似文献   
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