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1.
Olga Jordi 《Bird Study》2016,63(2):273-278
Capsule: Chick growth rates was sex-dependent in an Atlantic Yellow-legged Gull Larus michahellis population.

Aims: To describe the growth rate of Yellow-legged Gull chicks and sex-associated variations, and obtain a discriminant function to sex them using morphological data.

Methods: Fifty-two Yellow-legged Gull chicks from a colony in northern Iberia were measured for body mass, head and bill length, tarsus length and three other bill-length associated variables, from the hatching date up to the age of 36 days. Birds were sexed using DNA analysis.

Results: Using logistic models, chick growth rates was observed to be similar between the sexes, while the asymptote was higher among males for the majority of the variables. Discriminant analyses showed that the variable head+bill was very reliable to predict the sex of >80% of chicks at an early developmental stage, and 100% of chicks if combined with tarsus length and two more bill-length associated variables at the age of 35 days.

Conclusions: This is the first study using a discriminant analysis to sex Yellow-legged Gull chicks, and also the first to describe the growth function for the species. The growth rate varied between sexes because males showed higher asymptote values within the growth function.  相似文献   


2.
Background: In asymptomatic severe aortic stenosis (ASAS), treatment decisions are made on an individual basis, and case management presents a clinical conundrum.

Methods: We prospectively phenotyped consecutive patients with ASAS using echocardiography, exercise echocardiography, cardiac MRI and biomarkers (NT-proBNP, high-sensitivity troponin T (hs-TnT) and ST2) (n?=?58). The primary endpoint was a composite of cardiovascular death, new-onset symptoms, cardiac hospitalization, guideline-driven indication for valve replacement and cardiovascular death at 12?months.

Results: During the first year, 46.6% patients met primary endpoint. In multivariable analysis, aortic regurgitation ≥2 (p?=?0.01) and hs-TnT (p?=?0.007) were the only independent predictors of the primary endpoint. The best cutoff value was identified as hs-TnT >10ng/L, which was associated with a ~10-fold greater risk of the primary endpoint (HR, 9.62; 95% CI, 2.27–40.8; p?=?0.002). A baseline predictive model including age, sex and variables showing p?<?0.10 in univariable analyses showed an area under the curve (AUC) of 0.79(0.66–0.91). Incorporation of hs-TnT into this model increased the AUC to 0.90(0.81–0.98) (p?=?0.03). Patient reclassification with the model including hs-TnT yielded an NRI of 1.28(0.46–1.78), corresponding to 43% adequately reclassified patients.

Conclusions: In patients with ASAS, hs-TnT >10ng/L was associated with high risk of events within 12?months. Including hs-TnT in routine ASAS management markedly improved prediction metrics.  相似文献   


3.
Context: Hepatitis is an endemic disease worldwide leading to chronic and debilitating cancers. The viral agents and hepatotoxic substances lead to damage of hepatocytes and release of damage associated molecules in circulation. The lack of timely and rapid diagnosis of hepatitis results in chronic disease.

Objective: The present review aimed to describe regulation, release and functions of microRNAs (miR) during human liver pathology and insights into their promising use as noninvasive biomarkers of hepatitis.

Methods: Comprehensive data were collected from PubMed, ScienceDirect and the Web of Science databases utilizing the keywords “biomarkers”, “microRNAs” and “hepatic diseases”.

Results: The miRs are readily released in the body fluids and blood during HBV/HCV associated hepatitis as well as metabolic, alcoholic, drug induced and autoimmune hepatitis. The liver-specific microRNAs including miR-122, miR-130, miR-183, miR-196, miR-209 and miR-96 are potential indicators of liver injury (mainly via apoptosis, necrosis and necroptosis) or hepatitis with their varied expression during acute/fulminant, chronic, liver fibrosis/cirrhosis and hepato-cellular carcinoma.

Conclusions: The liver-specific miRs can be used as rapid and noninvasive biomarkers of hepatitis to discern different stages of hepatitis. Blocking or stimulating pathways associated with miR regulation in liver could unveil novel therapeutic strategies in the management of liver diseases.

  • Clinical significance
  • Liver specific microRNAs interact with cellular proteins and signaling molecules to regulate the expression of various genes controlling biological processes.

  • The circulatory level of liver specific microRNAs is indicator of severity of HBV and HCV infections as well as prognostic and therapeutic candidates.

  • The expression of liver specific microRNAs is strongly associated with infectious, drug-induced, hepatotoxic, nonalcoholic steatohepatitis and nonalcoholic fatty liver diseases.

  相似文献   

4.
Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome.

Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.

Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).

Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.  相似文献   


5.
Background: The remaining forests in the extensive contact zone between southern Amazonia (seasonal rain forest) and the Cerrado (savanna) biomes are at risk due to intense land-use and climate change.

Aims: To explore the vulnerability of these transitional forests to changes in land use and climate, we evaluated the effects of fragmentation and climatic variables on forest structure.

Methods: We measured the diameter and height of 14,185 trees with diameter ≥10 cm at 24 forest plots distributed over an area of 25,000 km2. For each plot, we obtained data on contemporary fragmentation and climatic variables.

Results: Forest structure variables (height, diameter, height:diameter allometry, biomass) varied significantly both within and among plots. The height, H:D and biomass of trees were positively correlated with annual precipitation and fragment area.

Conclusions: The association between forest structure and precipitation indicates that these forests plots are likely to be vulnerable to dry season intensification anticipated for the southern edge of the Amazon. Additionally, the reduction in the fragment area may contribute to reductions in forest biomass and tree height, and consequently ecosystem carbon stocks. Given the likely susceptibility of these forests, urgent conservation action is needed to prevent further habitat degradation.  相似文献   


6.
Background: Understanding floristic and geographic patterns in one of the most biodiverse regions in the world – the Atlantic forest of eastern Bahia, Brazil – can identify the drivers of diversity in tropical forests and provide useful information for biological conservation.

Aims: To understand the role of both climate and geographical location on variation in tree species composition in a region characterised by an abrupt transition from wet forests to semi-arid thorn-woodlands. To test whether a regional classification of forests according to elevation belts and leaf flush pattern is consistent with floristic composition.

Methods: We submitted 14,094 tree species occurrence records and 31 geo-climatic variables prepared for 57 sites in eastern Bahia, Brazil, to multivariate and regression analyses and variance partitioning.

Results: Climate and space were both significantly (P ≤ 0.05) contributing to explaining floristic variations. Actual evapotranspiration, duration of water deficit, and minimum temperature of coldest month were the main predictors. Floristic differences were significant except when comparing evergreen lower plains and upper plains forests.

Conclusions: Although distance among sites may play an important role, species composition is chiefly influenced by environmental gradients. This highlights environmental heterogeneity as a key factor in the planning of biodiversity conservation in tropical forests.  相似文献   


7.
Purpose: Hypercatecholaminemia-related heart failure has been proposed as the main cause of enterovirus A71-related (EV-A71) early mortality. The purpose of this study was to measure urine catecholamine concentrations in severe EV-A71-infected children.

Methods: A total of 35 children, aged 2.5?±?2.1 years, were divided into three groups. Group I: 15 septic shock patients, group II: 17?EV-A71-stage-2 patients, and group III: 3?EV-A71-stage-4 patients. The laboratory results, cardiac biomarkers and urine catecholamine concentrations were statistically analysed.

Results: Group I had the highest C-reactive protein (CRP) levels and group II had the lowest B-type natriuretic peptide (BNP) and its N-terminal prohormone among the groups (p?=?0.039, <0.01 and <0.01, respectively). Group III patients had significantly higher urine catecholamine and troponin-I values among the groups. If urine epinephrine (Epi) >134 ug/gCr, norepinephrine (NE) >176 ug/gCr and vanillylmandelic acid (VMA) >11.7?mg/gCr were used as the cutoff points to differentiate groups II and III, the sensitivities and specificity were all 100%.

Conclusions: The significantly elevated urine catecholamine concentrations in EV-A71-stage-4 patients support the hypothesis that hypercatecholaminemia-related heart failure is involved in severe EV-A71 infection. Urine catecholamines could be used as reliable biomarkers for differentiation of severe EV-A71 infection with or without heart failure and septic shock.  相似文献   


8.
Context: Genetics play a major role in development and pathophysiology of Type 2 diabetes mellitus (T2DM).

Objective: To asses the association of Guanine nucleotide-binding protein (GNB3) (C825T) gene's polymorphism with T2DM.

Materials and methods: A case–control study including 400 North Indians was performed using Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) approach to analyze genetic polymorphism.

Results: No significant difference was observed in genotype and allele frequencies of GNB3 gene on comparing cases with controls.

Discussion: Our study is in agreement with studies on Polish, Japanese, Hispanic-American and Danish populations who observed no significant association between GNB3 (C825T) polymorphism and T2DM.

Conclusion: GNB3 (C825T) polymorphism is not associated with T2DM.  相似文献   


9.
Investigating the methylation status of the circadian genes may contribute to a better understanding of the shift work-related circadian disruption in individuals exposed to artificial light at night. In the present study, we determined the methylation status of the circadian genes associated with a shift work pattern among nurses and midwives participating in a cross-sectional study in Lodz, Poland.

Quantitative methylation polymerase chain reaction assays were used to assess promoter CpG methylation in PER1, PER2, PER3, CRY1, CRY2, BMAL1, CLOCK, and NPAS2 in genomic DNA from whole blood of 347 women having a rotating-shift work schedule and 363 women working days only. The percentage of methylated reference (PMR) was assessed using fluorescent probes for PER1, PER2, PER3, CRY1, and NPAS2, and the percentage of gene methylation, as the methylation index (MI), using two sets of primers for BMAL1, CLOCK, and CRY2.

We tested the possible association between current and lifetime rotating night-shift work characteristics and circadian gene methylation by using proportional odds regression model with blood DNA methylation, categorized into tertiles, and adjusted for age, current smoking status, folate intake and blood collection time. The findings indicated that CpG methylation in PER2 promoter was significantly decreased (P < 0.004) among nurses and midwives currently working rotating shifts, as compared with day-working nurses and midwives. The lower percentage of PER2 methylation was associated with a higher monthly frequency of current night duties (2–7 night shifts, and eight or more night shifts per month) (P = 0.012) and was associated at borderline significance (P = 0.092) with the lifetime duration of shift work (>10 ≤ 20 years and >20 ≤ 43 years of rotating-shift work) among nurses and midwives (N = 710). Moreover, women with a longer lifetime duration of shift work presented a lower status of PER1 methylation (P = 0.040) than did the women with up to 10 years of rotating-shift work. Long lifetime duration of shift work (> 10 years) among current rotating night-shift workers (N = 347) was associated with BMAL1 hypomethylation (P = 0.013).

Among eight of the investigated circadian genes, only PER1, PER2, and BMAL1 showed differential methylation attributable to the rotating-shift work of nurses and midwives. The findings on blood-based DNA methylation in the circadian genes may provide a better insight into the mechanistic principles underlying the possible health effects of night-shift work but these should be verified in further studies recruiting larger populations of shift workers.  相似文献   


10.
Context: Leptin is produced in white adipose tissue, but also in human coronary atherosclerotic lesions.

Objective: The aim of this study is to assess the prognostic value of leptin in patients with proven coronary artery disease (CAD) (N?=?1907).

Methods: AtheroGene is a contemporary CAD cohort study (N?=?3229). Median follow-up time was 3.8 (Quartile 1/3 with 2.8/4.9) years.

Results: Leptin concentration was associated with a hazard ratio (HR) for the fully adjusted model of HR?=?1.32 in women but was not significant in men. The endpoint cardiovascular death and non-fatal myocardial infarction was observed in 167 patients.

Conclusion: In women with known CAD, increased leptin concentration is useful for predicting cardiovascular death and non-fatal myocardial infarction.  相似文献   


11.
Susmita Dutta 《Biomarkers》2019,24(4):317-324
Context: Pesticide poisoning and related deaths are a global concern, but there is little information about its effect on the occupationally exposed tea garden workers of North Bengal.

Objective: This study investigates the level of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the blood of the tea garden workers at risk of exposure to a mixture of pesticides.

Materials and methods: The study sample consisted of pesticide exposed workers, non-exposed (control), smokers and alcoholics. AChE and BuChE activity was measured and tested for significance.

Results: Results showed that AChE activity was half in the pesticide exposed individuals than controls (p≤ 0.001). BuChE activity was also significantly decreased in the pesticide exposed individuals than controls (p≤ 0.001), while AChE and BuChE activity in smokers and alcoholics were not different from that of controls. However, significantly decreased AChE and BuChE activities were recorded in pesticide exposed workers compared to smokers and alcoholics.

Conclusions: The results indicated that the decrease in enzyme activities in tea garden workers was due to mixed pesticides (containing organophosphates) exposure. Age was not found to influence the enzyme activities. However, the gender had little effect on the enzyme activities but the effect was not so prominent.  相似文献   


12.
Objectives: This study aims to explore the effect of bone marrow mesenchymal stem cells (BMSCs) on multiple myeloma (MM) development and the underlying mechanism.

Materials and Methods: BMSCs from C57BL/6 J mice were isolated and the third passage was used for subsequent experiments. Additionally, a series of in vitro transwell coculture assays were performed to explore the effects of BMSCs on the proliferation of MM cells 5TGM1 and CD4+ T cells. Furthermore, a 5TGM1-induced MM mice model was established. Moreover, PD-L1 shRNA was transfected into BMSCs to investigate whether PD-1/PD-L1 pathway involved in BMSCs-mediated regulation of T cells and MM growth.

Results: Data revealed that BMSCs significantly promoted 5TGM1 proliferation in a dose-dependent manner. Furthermore, BMSCs administration exerted stimulatory effects on MM development in terms of shortening the mouse survival rate, promoting tumor growth, and enhancing inflammatory infiltration in the MM model mice. Moreover, BMSCs decreased the percentage of Th1 and Th17 cells, whereas increased that of Th2 and Treg cells. Their corresponding cytokines of these T cell subsets showed similar alteration in the presence of BMSCs. Additionally, BMSCs significantly suppressed CD4+ T cell proliferation. We also found that PD-L1 shRNA inhibited 5TGM1 proliferation likely through activation of CD4+ T cells. Further in vivo experiments confirmed that PD-L1 inhibition attenuated BMSCs-induced MM growth, inflammation infiltration and imbalance of Th1/Th2 and Th17/Treg.

Conclusion: In summary, our findings demonstrated that BMSCs promoted cell proliferation of MM through inhibiting T cell immune responses via PD-1/PD-L1 pathway.  相似文献   


13.
Background: Species composition of plant communities is shaped by the interplay between dispersal limitation, environmental filters and stochastic events.

Aims: The aim of this work was to investigate the effects of dispersal limitation and environmental filtering on tree recruitment. To accomplish this, we employed the unified neutral theory of biodiversity and biogeography to examine migration within the metacommunity, defined as a set of interacting local communities linked by the dispersal of multiple potentially interacting species.

Methods: We sampled 12,975 individuals with dbh ≥ 1 cm in 26 1-ha permanent plots, including habitats of terra firme, transitional forests, várzea and campinarana, on the upper Madeira River, Brazilian Amazon.

Results: Campinarana drew individuals from outside the metacommunity species pool at a mean probability of recruitment of 0.06, a much lower probability than terra firme (0.31), transitional (0.21) and várzea forests (0.22). Environmental variables, such as water table depth, soil texture and fertility, were related to differences in community assembly.

Conclusions: Species abundance distribution and diversity patterns of plant assemblages in a large river landscape in the Amazon highlight the importance of environmental heterogeneity that conditions beta-diversity. The high variation in recruitment probabilities from the metacommunity species pool to local communities suggests high habitat variability in the process of maintaining patterns of local diversity.  相似文献   


14.
Background: The dwarf shrub Vaccinium myrtillus – with high cover, height, and fruit production – benefits capercaillie (Tetrao urogallus).

Aims: Our aim was to quantify landscape (e.g. elevation, geographic location, and precipitation), site (e.g. overstorey cover and stoniness) and very fine scale factors (e.g. spatial associations in the understorey) that affect cover, height, and fruit production of V. myrtillus in subalpine forests in thePyrenees, with understorey usually dominated by Rhododendron ferrugineum.

Methods: We sampled 155 plots (0.5 m × 5 m) in six sites. For each plot, in the understorey layer, we assessed species cover, height for R. ferrugineum and V. myrtillus, number of total fruits in V. myrtillus, and spatial associations among V. myrtillus and the remaining cover types.

Results: Overstorey cover negatively influenced V. myrtillus cover, its height, and particularly, the number of fruits, which was also negatively influenced by R. ferrugineum cover. Associations between R. ferrugineum and V. myrtillus were site dependent, while V. myrtillus showed mostly positive associations with grasses and mosses.

Conclusions: Reducing overstorey and R. ferrugineum cover has the strongest positive effect on increasing V. myrtillus fruit production, but with additional positive effects on V. myrtillus cover and height. Increases in grass and moss coverage could favour V. myrtillus.  相似文献   


15.
Background: Management actions in mountain heathlands oriented to increasing the cover of Vaccinium myrtillus promote mowing of Calluna vulgaris to avoid competition. However, such action ignores the fact that plant–plant interactions range from competition to facilitation under different stress conditions.

Aims: To test whether the interactions between these two species are related to competition or facilitation, which would change the perspective for their management in mountain heathlands.

Methods: A total of 40 experimental plots located in a montane heathland (northern Spain) were selected. Calluna or Vaccinium plants were either cut at ground level or not cut, and plots were fertilized with nitrogen or not in a three-factorial design. Vegetative and reproductive shoot mass and length of the current year’s shoots were estimated in two consecutive years for both species. Herbivory on Vaccinium by browsing ungulates was compared in control plots and plots where Calluna had been cut 2 yrs ago.

Results: The two study species co-occurred in 72.4% of the sampled plots, although Calluna was more abundant. Vaccinium growth was greater in plots with Calluna than in plots where Calluna had been cut. Browsing on Vaccinium was also higher in plots were Calluna had been cut, and the effect of fertilization was only significant on the reproductive biomass of Calluna.

Conclusions: Contrary to initial proposals, our results suggest that Vaccinium does not always benefit from the cutting of Calluna in heathlands. Thus, the management of Cantabrian mountain heathlands should consider maintaining Calluna in order to facilitate the growth of Vaccinium.  相似文献   


16.
Capsule: Pre-fledging survival in a Yellow-legged Gull Larus michahellis population in northern Iberia is negatively correlated to hatching date.

Aims: To explore which factors have more importance in determining the pre-fledging daily survival rates in a Yellow-legged Gull population from northern Iberia. Specifically, we tested for the effect of hatching date and order, body size and condition and meteorological conditions on pre-fledging survival.

Methods: Cormack–Jolly–Seber models with mixtures were used to model daily survival rates.

Results: Daily survival rates were mostly negatively affected by hatching date.

Conclusions: Hatching date was the most important factor affecting survival of chicks during the pre-fledging period in a Yellow-legged Gull colony from northern Iberia.  相似文献   


17.
Objectives: Notch1 regulates tumor biology in a complex, context-dependent manner. The roles of Notch1 in tongue cancer are still controversial. The aim of this study is to investigate the roles of Notch1 in tongue cancer.

Materials and Methods: The expression of Notch1 was tested between tongue cancer and normal samples by using immunohistochemistry. Tongue cancer cells were transfected with siRNA or plasmid, respectively. Cell proliferation, apoptosis, migration and invasion ability were tested in appropriate ways. The subcutaneous tumor model was established to observe the tumor growth.

Results: Notch1 was upregulated in tongue carcinoma tissues and the expression of Notch1 was related with tumor stage and differentiation. Overexpression of Notch1 could increase tongue cancer cells proliferation, invasion and migration. But inhibited the expression of Notch1 could decrease cells proliferation, invasion and migration and promote cell apoptosis in vitro and in vivo.

Conclusion: Our results prove that the oncogenic role of Notch1 in tongue cancer and provide the direction of targeted therapy of tongue cancer.  相似文献   


18.
Context: Poly-l-glutamic acid (PGA) is an anionic polymer with a large number of carboxyl groups that can interact electrostatically with cationic drugs such as doxorubicin (DOX).

Objective: For stable encapsulation of DOX into liposomes, we prepared triethylamine (TEA)-PGA-liposomes using PGA as an internal trapping agent.

Methods: We prepared TEA-PGA-liposomes by remote loading of DOX with a TEA gradient into preformed liposomes prepared with 1, 2, or 4?mg/mL PGA (molecular weights 4800, 9800, and 20 500), and evaluated their biodistribution and antitumor effects on Lewis lung carcinoma (LLC) tumor-bearing mice.

Results: TEA-PGA-liposomes using the higher the molecular weight or concentration of PGA showed a slower release of DOX from the liposomes. TEA-PGA-liposomes prepared with a high concentration of PGA could enhance DOX accumulation in tumors and prolonged DOX circulation in the serum, indicating that DOX may be retained stably in the liposomal interior by interaction with PGA. Furthermore, injection of TEA-PGA-liposomes prepared with 4?mg/mL of PGA9800 or 2?mg/mL PGA20500 strongly inhibited tumor growth in LLC tumor-bearing mice.

Conclusions: PGA may be a potential trapping agent for liposomal DOX for tumor drug delivery.  相似文献   


19.
Background: Medemia argun is a rare wild palm tree species. Its global existence is assumed to include the main population of about 1000 trees in the Nubian Desert of Sudan and some scattered individuals in southern Egypt. The species had previously been assumed to be extinct, but then reported to be extant about 20 years ago.

Aims: To assess genetic variation and explore population genetic structure of M. argun, through development and analysis of microsatellite markers.

Methods: The genome sequence mining approach was applied in order to identify microsatellites in the chloroplast genome of Bismarckia nobilis, a species closely related of M. argun. A set of 49 markers were designed, and their characteristics are now provided. Seven chloroplast DNA markers were developed for use in the genetic characterisation of this threatened species.

Results: Five markers were found polymorphic in M. argun, which enabled the assessment of the genetic diversity of the species. Significant genetic differentiation was observed among generations and collection sites, accompanied by low genetic variation. The seven markers developed were polymorphic among the wild relatives Hyphaene thebaica and Borassus aethiopum.

Conclusions: This is the first study to report molecular markers for M. argun. Our results suggest that the genetic consequences of population fragmentation in M. argun are beginning to be evident.  相似文献   


20.
Background: Translocating plants for conservation purposes can be a useful tool to enhance existing populations, restore lost populations or create new ones, but has rarely been done for bryophytes, especially liverworts.

Aims: Here, the leafy liverwort Herbertus hutchinsiae, a representative species of oceanic-montane liverwort-rich heath, was translocated to unoccupied habitat within its current range, to establish whether its restricted distribution is due to habitat or dispersal limitation.

Methods: Feasibility of establishing new populations outside the current distribution range was assessed, to test the suitability of the species for assisted colonisation. Furthermore, transplants were grown at degraded sites where the species had declined to assess potential for restoration.

Results: Although maximal growth rates occurred within-range, transplants grew at all sites, indicating that the species could be dispersal limited; a conclusion supported by distribution modelling.

Conclusions: Assisted colonisation is thus an option for this species to overcome dispersal limitation and to track future climate space. Reinforcement of populations at degraded sites is only recommended if the pressure causing the degradation has been removed. These findings provide an evidence base for practical conservation management.  相似文献   


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