145 research outputs found
Differential effectiveness of berry polyphenols as anti-giardial agents
Following previous work on the anti-giardial effect of blueberry polyphenols, a range of polyphenol-rich extracts from berries and other fruits was screened for their ability to kill Giardia duodenalis, an intestinal parasite of humans. Polyphenol-rich extracts were prepared from berries using solid-phase extraction and applied to trophozoites of Giardia duodenalis grown in vitro. All berry extracts caused inhibition at 166 μg gallic acid equivalents (GAE)/ml phenol content but extracts from strawberry, arctic bramble, blackberry and cloudberry were as effective as the currently used drug, metronidazole, causing complete trophozoite mortality in vitro. Cloudberry extracts were found to be the most effective causing effectively complete trophozoite mortality at 66 μg GAE/ml. The polyphenol composition of the more effective berry extracts suggested that the presence of ellagitannins could be an important factor. However, the potency of cloudberry could be related to high ellagitannin content but also to the presence of substantial amounts of unconjugated p-coumaric acid and benzoic acid. These in vitro effects occur at concentrations easily achievable in the gut after berry ingestion and we discuss the likelihood that berry extracts could be effective anti-giardial agents in vivo
Post-translational deregulation of YAP1 is genetically controlled in rat liver cancer and determines the fate and stem-like behavior of the human disease
Previous studies showed that YAP1 is over-expressed in hepatocellular carcinoma (HCC). Here we observed higher expression of Yap1/Ctgf axis in dysplastic nodules and HCC chemically-induced in F344 rats, genetically susceptible to hepatocarcinogenesis, than in lesions induced in resistant BN rats. In BN rats, highest increase in Yap1-tyr357, p73 phosphorylation and Caspase 3 cleavage occurred. In human HCCs with poorer prognosis ( 3 years survival; HCCB). In the latter, higher levels of phosphorylated YAP1-ser127, YAP1-tyr357 and p73, YAP1 ubiquitination, and Caspase 3 cleavage occurred. Expression of stemness markers NANOG, OCT-3/4, and CD133 were highest in HCCP and correlated with YAP1 and YAP1-TEAD levels. In HepG2, Huh7, and Hep3B cells, forced YAP1 over-expression led to stem cell markers expression and increased cell viability, whereas inhibition of YAP1 expression by specific siRNA, or transfection of mutant YAP1 which does not bind to TEAD, induced opposite alterations. These changes were associated, in Huh7 cells transfected with YAP1 or YAP1 siRNA, with stimulation or inhibition of cell migration and invasivity, respectively. Furthermore, transcriptome analysis showed that YAP1 transfection in Huh7 cells induces over-expression of genes involved in tumor stemness. In conclusion, Yap1 post-translational modifications favoring its ubiquitination and apoptosis characterize HCC with better prognosis, whereas conditions favoring the formation of YAP1-TEAD complexes are associated with aggressiveness and acquisition of stemness features by HCC cells
Molecular-based estimate of species number, phylogenetic relationships and divergence times for the genus Stenotaenia (Chilopoda, Geophilomorpha) in the Italian region
Stenotaenia is one of the largest and most widespread genera of geophilid centipedes in the Western Palearctic, with a very uniform morphology and about fifteen species provisionally recognized. For a better understanding of Stenotaenia species-level taxonomy, we have explored the possibility of using molecular data. As a preliminary assay, we sampled twelve populations, mainly from the Italian region, and analyzed partial sequences of the two genes COI and 28S. We employed a DNA-barcoding approach, complemented by a phylogenetic analysis coupled with divergence time estimation. Assuming a barcoding gap of 10–16% K2P pairwise distances, we found evidence for the presence of at least six Stenotaenia species in the Italian region, which started diverging about 50 million years ago, only partially matching with previously recognized species. We found that small-sized oligopodous species belong to a single clade that originated about 33 million years ago, and obtained some preliminary evidence of the related genus Tuoba being nested within Stenotaenia
Carbon concentration declines with decay class in tropical forest woody debris
Carbon stored in woody debris is a key carbon pool in forest ecosystems. The most widely-used method to convert woody debris volume to carbon is by first multiplying field-measured volume with wood density to obtain necromass, and then assuming that a fixed proportion (often 50%) of the necromass is carbon. However, this crucial assumption is rarely tested directly, especially in the tropics. The aim of this study is to verify the field carbon concentration values of living trees and woody debris in two distinct tropical forests in Taiwan. Wood from living trees and woody debris across five decay classes was sampled to measure density and carbon concentrations. We found that both wood density and carbon concentration (carbon mass/total mass) declined significantly with the decay class of the wood. Mean (±SE) carbon concentration values for living trees were 44.6 ± 0.1%, while for decay classes one to five they were respectively 41.1 ± 1.4%, 41.4 ± 1.0%, 37.7 ± 1.3%, 30.5 ± 2.0%, and 19.6 ± 2.2%. Total necromass carbon stock was low, only 3.33 ± 0.55 Mg C ha−1 in the windward forest (Lanjenchi) and 4.65 ± 1.63 Mg C ha−1 in the lowland forest (Nanjenshan). Applying the conventional 50% necromass carbon fraction value would cause a substantial overestimate of the carbon stocks in woody debris of between 17% and 36%, or about 1 Mg of carbon per hectare. The decline in carbon concentration and the increase of variances in the heavily decayed class suggest that in high-diversity tropical forests there are diverse decomposition trajectories and that assuming a fixed carbon fraction across woody pieces is not justified. Our work reveals the need to consider site-specific and decay class-specific carbon concentrations in order to accurately estimate carbon stocks and fluxes in forest ecosystems. If the marked decline in carbon content with necromass decay is typical of tropical forests, the dead wood carbon pool in the biome needs revision and is likely to be overestimate
Complications of mechanical thrombectomy for acute ischemic stroke: Incidence, risk factors, and clinical relevance in the Italian Registry of Endovascular Treatment in acute stroke
BACKGROUND: There are limited data concerning procedure-related complications of endovascular thrombectomy for large vessel occlusion strokes. AIMS: We evaluated the cumulative incidence, the clinical relevance in terms of increased disability and mortality, and risk factors for complications. METHODS: From January 2011 to December 2017, 4799 patients were enrolled by 36 centers in the Italian Registry of Endovascular Stroke Treatment. Data on demographic and procedural characteristics, complications, and clinical outcome at three months were prospectively collected. RESULTS: The complications cumulative incidence was 201 per 1000 patients undergoing endovascular thrombectomy. Ongoing antiplatelet therapy (p < 0.01; OR 1.82, 95% CI: 1.21-2.73) and large vessel occlusion site (carotid-T, p < 0.03; OR 3.05, 95% CI: 1.13-8.19; M2-segment-MCA, p < 0.01; OR 4.54, 95% CI: 1.66-12.44) were associated with a higher risk of subarachnoid hemorrhage/arterial perforation. Thrombectomy alone (p < 0.01; OR 0.50, 95% CI: 0.31-0.83) and younger age (p < 0.04; OR 0.98, 95% CI: 0.97-0.99) revealed a lower risk of developing dissection. M2-segment-MCA occlusion (p < 0.01; OR 0.35, 95% CI: 0.19-0.64) and hypertension (p < 0.04; OR 0.77, 95% CI: 0.6-0.98) were less related to clot embolization. Higher NIHSS at onset (p < 0.01; OR 1.04, 95% CI: 1.02-1.06), longer groin-to-reperfusion time (p < 0.01; OR 1.05, 95% CI: 1.02-1.07), diabetes (p < 0.01; OR 1.67, 95% CI: 1.25-2.23), and LVO site (carotid-T, p < 0.01; OR 1.96, 95% CI: 1.26-3.05; M2-segment-MCA, p < 0.02; OR 1.62, 95% CI: 1.08-2.42) were associated with a higher risk of developing symptomatic intracerebral hemorrhage compared to no/asymptomatic intracerebral hemorrhage. The subgroup of patients treated with thrombectomy alone presented a lower risk of symptomatic intracerebral hemorrhage (p < 0.01; OR 0.70; 95% CI: 0.55-0.90). Subarachnoid hemorrhage/arterial perforation and symptomatic intracerebral hemorrhage after endovascular thrombectomy worsen both functional independence and mortality at three-month follow-up (p < 0.01). Distal embolization is associated with neurological deterioration (p < 0.01), while arterial dissection did not affect clinical outcome at follow-up. CONCLUSIONS: Complications globally considered are not uncommon and may result in poor clinical outcome. Early recognition of risk factors might help to prevent complications and manage them appropriately in order to maximize endovascular thrombectomy benefits
HLA class I and II diversity contributes to the etiologic heterogeneity of non-Hodgkin lymphoma subtypes
A growing number of loci within the human leukocyte antigen (HLA) region have been implicated in non-Hodgkin lymphoma (NHL) etiology. Here, we test a complementary hypothesis of "heterozygote advantage" regarding the role of HLA and NHL, whereby HLA diversity is beneficial and homozygous HLA loci are associated with increased disease risk. HLA alleles at class I and II loci were imputed from genome-wide association studies (GWAS) using SNP2HLA for 3,617 diffuse large B-cell lymphomas (DLBCL), 2,686 follicular lymphomas (FL), 2,878 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 741 marginal zone lymphomas (MZL), and 8,753 controls of European descent. Both DLBCL and MZL risk were elevated with homozygosity at class I HLA-B and -C loci (OR DLBCL = 1.31, 95% CI = 1.06–1.60; OR MZL = 1.45, 95% CI = 1.12–1.89) and class II HLA-DRB1 locus (OR DLBCL = 2.10, 95% CI = 1.24–3.55; OR MZL = 2.10, 95% CI = 0.99–4.45). Increased FL risk was observed with the overall increase in number of homozygous HLA class II loci (P trend < 0.0001, FDR = 0.0005). These results support a role for HLA zygosity in NHL etiology and suggests that distinct immune pathways may underly the etiology of the different NHL subtypes. Significance: HLA gene diversity reduces risk for non-Hodgkin lymphoma
Post-translational deregulation of YAP1 is genetically controlled in rat liver cancer and determines the fate and stem-like behavior of the human disease
Previous studies showed that YAP1 is over-expressed in hepatocellular carcinoma
(HCC). Here we observed higher expression of Yap1/Ctgf axis in dysplastic nodules and
HCC chemically-induced in F344 rats, genetically susceptible to hepatocarcinogenesis,
than in lesions induced in resistant BN rats. In BN rats, highest increase in Yap1-
tyr357, p73 phosphorylation and Caspase 3 cleavage occurred. In human HCCs with
poorer prognosis (< 3 years survival after partial liver resection, HCCP), levels of
YAP1, CTGF, 14–3–3, and TEAD proteins, and YAP1-14-3-3 and YAP1-TEAD complexes
were higher than in HCCs with better outcome (> 3 years survival; HCCB). In the
latter, higher levels of phosphorylated YAP1-ser127, YAP1-tyr357 and p73, YAP1
ubiquitination, and Caspase 3 cleavage occurred. Expression of stemness markers
NANOG, OCT-3/4, and CD133 were highest in HCCP and correlated with YAP1 and
YAP1-TEAD levels. In HepG2, Huh7, and Hep3B cells, forced YAP1 over-expression
led to stem cell markers expression and increased cell viability, whereas inhibition
of YAP1 expression by specific siRNA, or transfection of mutant YAP1 which does
not bind to TEAD, induced opposite alterations. These changes were associated, in
Huh7 cells transfected with YAP1 or YAP1 siRNA, with stimulation or inhibition of cell
migration and invasivity, respectively. Furthermore, transcriptome analysis showed
that YAP1 transfection in Huh7 cells induces over-expression of genes involved
in tumor stemness. In conclusion, Yap1 post-translational modifications favoring
its ubiquitination and apoptosis characterize HCC with better prognosis, whereas
conditions favoring the formation of YAP1-TEAD complexes are associated with
aggressiveness and acquisition of stemness features by HCC cells
Reverse and Conventional Chemical Ecology Approaches for the Development of Oviposition Attractants for Culex Mosquitoes
Synthetic mosquito oviposition attractants are sorely needed for surveillance and control programs for Culex species, which are major vectors of pathogens causing various human diseases, including filariasis, encephalitis, and West Nile encephalomyelitis. We employed novel and conventional chemical ecology approaches to identify potential attractants, which were demonstrated in field tests to be effective for monitoring populations of Cx. p. quinquefasciatus in human dwellings. Immunohistochemistry studies showed that an odorant-binding protein from this species, CquiOBP1, is expressed in trichoid sensilla on the antennae, including short, sharp-tipped trichoid sensilla type, which house an olfactory receptor neuron sensitive to a previously identified mosquito oviposition pheromone (MOP), 6-acetoxy-5-hexadecanolide. CquiOBP1 exists in monomeric and dimeric forms. Monomeric CquiOBP1 bound MOP in a pH-dependent manner, with a change in secondary structure apparently related to the loss of binding at low pH. The pheromone antipode showed higher affinity than the natural stereoisomer. By using both CquiOBP1 as a molecular target in binding assays and gas chromatography-electroantennographic detection (GC-EAD), we identified nonanal, trimethylamine (TMA), and skatole as test compounds. Extensive field evaluations in Recife, Brazil, a region with high populations of Cx. p. quinquefasciatus, showed that a combination of TMA (0.9 µg/l) and nonanal (0.15 ng/µl) is equivalent in attraction to the currently used infusion-based lure, and superior in that the offensive smell of infusions was eliminated in the newly developed synthetic mixture
HLA class I and II diversity contributes to the etiologic heterogeneity of non-Hodgkin lymphoma subtypes
A growing number of loci within the human leukocyte antigen (HLA) region have been implicated in non-Hodgkin lymphoma (NHL) etiology. Here, we test a complementary hypothesis of "heterozygote advantage" regarding the role of HLA and NHL, whereby HLA diversity is beneficial and homozygous HLA loci are associated with increased disease risk. HLA alleles at class I and II loci were imputed from genome-wide association studies (GWAS) using SNP2HLA for: 3,617 diffuse large B-cell lymphomas (DLBCL), 2,686 follicular lymphomas (FL), 2,878 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 741 marginal zone lymphomas (MZL), and 8,753 controls of European descent. Both DLBCL and MZL risk were elevated with homozygosity at class I HLA-B and -C loci (OR DLBCL=1.31, 95% CI=1.06-1.60; OR MZL=1.45, 95% CI=1.12-1.89) and class II HLA-DRB1 locus (OR DLBCL=2.10, 95% CI=1.24-3.55; OR MZL= 2.10, 95% CI=0.99-4.45). Increased FL risk was observed with the overall increase in number of homozygous HLA class II loci (p-trend<0.0001, FDR=0.0005). These results support a role for HLA zygosity in NHL etiology and suggests that distinct immune pathways may underly the etiology of the different NHL subtypes
No Future Growth Enhancement Expected at the Northern Edge for European Beech due to Continued Water Limitation.
With ongoing global warming, increasing water deficits promote physiological stress on forest ecosystems with negative impacts on tree growth, vitality, and survival. How individual tree species will react to increased drought stress is therefore a key research question to address for carbon accounting and the development of climate change mitigation strategies. Recent tree-ring studies have shown that trees at higher latitudes will benefit from warmer temperatures, yet this is likely highly species-dependent and less well-known for more temperate tree species. Using a unique pan-European tree-ring network of 26,430 European beech (Fagus sylvatica L.) trees from 2118 sites, we applied a linear mixed-effects modeling framework to (i) explain variation in climate-dependent growth and (ii) project growth for the near future (2021-2050) across the entire distribution of beech. We modeled the spatial pattern of radial growth responses to annually varying climate as a function of mean climate conditions (mean annual temperature, mean annual climatic water balance, and continentality). Over the calibration period (1952-2011), the model yielded high regional explanatory power (R2 = 0.38-0.72). Considering a moderate climate change scenario (CMIP6 SSP2-4.5), beech growth is projected to decrease in the future across most of its distribution range. In particular, projected growth decreases by 12%-18% (interquartile range) in northwestern Central Europe and by 11%-21% in the Mediterranean region. In contrast, climate-driven growth increases are limited to around 13% of the current occurrence, where the historical mean annual temperature was below ~6°C. More specifically, the model predicts a 3%-24% growth increase in the high-elevation clusters of the Alps and Carpathian Arc. Notably, we find little potential for future growth increases (-10 to +2%) at the poleward leading edge in southern Scandinavia. Because in this region beech growth is found to be primarily water-limited, a northward shift in its distributional range will be constrained by water availability
- …