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1.
Martina Ferraguti  Sergio Magallanes  Jéssica Jiménez-Peñuela  Josué Martínez-de la Puente  Luz Garcia-Longoria  Jordi Figuerola  Jaime Muriel  Tamer Albayrak  Staffan Bensch  Camille Bonneaud  Rohan H. Clarke  Gábor Á. Czirják  Dimitar Dimitrov  Kathya Espinoza  John G. Ewen  Farah Ishtiaq  Wendy Flores-Saavedra  László Zsolt Garamszegi  Olof Hellgren  Dita Horakova  Kathryn P. Huyvaert  Henrik Jensen  Asta Križanauskienė  Marcos R. Lima  Charlene Lujan-Vega  Eyðfinn Magnussen  Lynn B. Martin  Kevin D. Matson  Anders Pape Møller  Pavel Munclinger  Vaidas Palinauskas  Péter L. Pap  Javier Pérez-Tris  Swen C. Renner  Robert Ricklefs  Sergio Scebba  Ravinder N. M. Sehgal  Manuel Soler  Eszter Szöllősi  Gediminas Valkiūnas  Helena Westerdahl  Pavel Zehtindjiev  Alfonso Marzal 《Global Ecology and Biogeography》2023,32(5):809-823

Aim

The increasing spread of vector-borne diseases has resulted in severe health concerns for humans, domestic animals and wildlife, with changes in land use and the introduction of invasive species being among the main possible causes for this increase. We explored several ecological drivers potentially affecting the local prevalence and richness of avian malaria parasite lineages in native and introduced house sparrows (Passer domesticus) populations.

Location

Global.

Time period

2002–2019.

Major taxa studied

Avian Plasmodium parasites in house sparrows.

Methods

We analysed data from 2,220 samples from 69 localities across all continents, except Antarctica. The influence of environment (urbanization index and human density), geography (altitude, latitude, hemisphere) and time (bird breeding season and years since introduction) were analysed using generalized additive mixed models (GAMMs) and random forests.

Results

Overall, 670 sparrows (30.2%) were infected with 22 Plasmodium lineages. In native populations, parasite prevalence was positively related to urbanization index, with the highest prevalence values in areas with intermediate urbanization levels. Likewise, in introduced populations, prevalence was positively associated with urbanization index; however, higher infection occurred in areas with either extreme high or low levels of urbanization. In introduced populations, the number of parasite lineages increased with altitude and with the years elapsed since the establishment of sparrows in a new locality. Here, after a decline in the number of parasite lineages in the first 30 years, an increase from 40 years onwards was detected.

Main conclusions

Urbanization was related to parasite prevalence in both native and introduced bird populations. In invaded areas, altitude and time since bird introduction were related to the number of Plasmodium lineages found to be infecting sparrows.  相似文献   
2.
Tat-interactive protein 60 kDa (TIP60, also known as lysine acetyltransferase 5 [KAT5]) is a member of the MYST protein family with histone acetyltransferase activity. Recent studies have reported that TIP60 has multiple functions in many signal transduction mechanisms, especially p53-mediated apoptosis. Although the activation of apoptosis signaling pathways requires the presence of cellular reactive oxygen species (ROS) at a certain level, an imbalance between the production and consumption of ROS in cells results in oxidative stress (OS). In this study, we investigated for the first time how the absence of the Tip60 gene in the liver affects gene expression, enzyme activity, and protein expression of the hepatic antioxidant members localized in the cytoplasm, including superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST). First, we successfully generated liver-specific Tip60 knockout mice (mutants) using Cre/LoxP recombination. The reduced glutathione level and nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) expression, a marker of OS, increased significantly in the Tip60 mutant liver. Gene expression, activity, and protein expression of the enzymatic antioxidant system, including SOD, CAT, GR, GPx, and GST were investigated in mutants and control groups. Despite a significant correlation between the gene, enzyme activity, and protein content for CAT and GR, this was not true for SOD and GPx. The overall results suggest that TIP60 acts on the hepatic antioxidant system both at the gene and protein levels, but the actual effect of the deletion of Tip60 is observed at the protein level, especially for SOD and GPx.  相似文献   
3.
In this study, a new phthalonitrile derivative namely 4-[(2,4-difluorophenyl)ethynyl]phthalonitrile ( 1 ) and its metal phthalocyanines ( 2 and 3 ) were synthesized. The resultant compounds were conjugated to silver nanoparticles and characterized using transmission electron microscopy (TEM) images. The biological properties of compounds ( 1 – 3 ), their nanoconjugates ( 4 – 6 ), and silver nanoparticles ( 7 ) were examined for the first time in this study. The antioxidant activities of biological candidates ( 1 – 7 ) were studied by applying the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The highest antioxidant activity was obtained 97.47 % for 200 mg/L manganese phthalocyanine-silver nanoconjugates ( 6 ). The antimicrobial and antimicrobial photodynamic therapy (APDT) activities of biological candidates ( 1 – 7 ) were examined using a micro-dilution assay. The highest MIC value was obtained 8 mg/L for nanoconjugate 6 against E. hirae. The studied compounds and their silver nanoconjugates exhibited high APDT activities against all the studied microorganisms. The most effective APDT activities were obtained 4 mg/L for nanoconjugates ( 5 and 6 ) against L. pneumophila and E. hirae, respectively. All the studied biological candidates displayed high cell viability inhibition activities against E. coli cell growth. The biofilm inhibition activities of the tested biological candidates were also investigated against S. aureus and P. Aeruginosa. Biological candidates ( 1 – 6 ) can be considered efficient metal nanoparticle-based materials for multi-disciplinary biological applications.  相似文献   
4.
In this study, we investigated the combined treatment of 5-fluorouracil (5-FU) and Anatolian propolis extract (PE) on colorectal cancer (CRC)using in vitro and in vivo studies. We exposed luciferase-transfected (Lovo-Luc CRC) cells and healthy colon cells (CCD-18Co) to varying concentrations of 5-FU and PE to assess their genotoxic, apoptotic, and cytotoxic effects, as well as their intracellular reactive oxygen species (iROS) levels. We also developed a xenograft model in nude mice and evaluated the anti-tumor effects of PE and 5-FU using various methods. Our findings showed that the combination of PE and 5-FU had selectivity against cancer cells, particularly at higher doses, and enhanced the anti-tumor effectiveness of 5-FU against colon CRC. The results suggest that PE can reduce side effects and increase the effectiveness of 5-FU through iROS generation in a dose-dependent manner.  相似文献   
5.
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers, which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects.  相似文献   
6.
The ER‐bound kinase/endoribonuclease (RNase), inositol‐requiring enzyme‐1 (IRE1), regulates the phylogenetically most conserved arm of the unfolded protein response (UPR). However, the complex biology and pathology regulated by mammalian IRE1 cannot be fully explained by IRE1’s one known, specific RNA target, X box‐binding protein‐1 (XBP1) or the RNA substrates of IRE1‐dependent RNA degradation (RIDD) activity. Investigating other specific substrates of IRE1 kinase and RNase activities may illuminate how it performs these diverse functions in mammalian cells. We report that macrophage IRE1 plays an unprecedented role in regulating phosphatidylinositide‐derived signaling lipid metabolites and has profound impact on the downstream signaling mediated by the mammalian target of rapamycin (mTOR). This cross‐talk between UPR and mTOR pathways occurs through the unconventional maturation of microRNA (miR) 2137 by IRE1’s RNase activity. Furthermore, phosphatidylinositol (3,4,5) phosphate (PI(3,4,5)P3) 5‐phosphatase‐2 (INPPL1) is a direct target of miR‐2137, which controls PI(3,4,5)P3 levels in macrophages. The modulation of cellular PI(3,4,5)P3/PIP2 ratio and anabolic mTOR signaling by the IRE1‐induced miR‐2137 demonstrates how the ER can provide a critical input into cell growth decisions.  相似文献   
7.

Determination of the optimal inoculation method and concentration to use for plant-bacteria interaction studies is important in many cases, such as the phytoremediation of heavy metals and other toxic compounds in contaminated areas. The aim of this study was to compare different concentrations and times of inoculation of Pseudomonas putida with various growth stages of Arabidopsis thaliana in 14-d in vitro cultures. A significant beneficial impact of the bacterium was detected in the shoot length and root weight of seedlings. The highest shoot length and root fresh and dry weights were detected in 14-d and 2 × 103 cfu mL−1 inoculated samples. In addition, the increase in root weight could be visualized with crystal violet staining, as relatively more root hair and lateral root formation occurred in seedlings inoculated with moderate concentrations of bacteria, possibly due to the ability of P. putida to produce indole-acetic acid. Moreover, the highest photosynthetic pigment accumulation was obtained with the highest bacterial inoculum (2 × 106 cfu mL−1), which was tested in 0- or 3-d-old seedlings. Rhizospheric bacterial colonization was also visualized with GFP-labeled bacteria by confocal microscopy. These results showed that biotization of A. thaliana with P. putida KT2440 did not cause severe oxidative stress in seedlings, because H2O2 accumulation levels together with CAT and POX activities were not significantly induced. Therefore, this strain could be used for several applications based on plant-bacteria interactions.

  相似文献   
8.

The metabolic syndrome (MetS) and pathologies associated with metabolic dysregulations a worldwide growing problem. Our previous study demonstrated that pioglitazone (PGZ) has beneficial effects on metabolic syndrome associated disturbances in the heart. However, mechanism mediating the molecular alterations of Ubiquitin proteasome system (UPS) and autophagy has not been investigated in rat pancreas with metabolic syndrome. For this reason, we first aimed to detect whether MetS effects on the expression of UPS (p97/VCP, SVIP, Ubiquitin) and autophagic (p62, LC3) proteins in rat pancreas. The second aim of the study was to find impact of pioglitazone on the expression of UPS and autophagic proteins in MetS rat pancreas. To answer these questions, metabolic syndrome induced rats were used as a model and treated with pioglitazone for 2 weeks. Pancreatic tissue injuries, fibrosis and lipid accumulation were evaluated histopathologically in control, MetS and MetS-PGZ groups. Apoptosis and cell proliferation of pancreatic islet cells were assessed in all groups. UPS and autophagic protein expressions of pancreas in all groups were detected by using immunohistochemistry, double-immunfluorescence and Western blotting. Compared with the controls, the rat fed with high sucrose exhibited signs of metabolic syndrome, such as higher body weight, insulin resistance, higher triglyceride level and hyperglycaemia. MetS rats showed pancreatic tissue degeneration, fibrosis and lipid accumulation when their pancreas were examined with Hematoxilen-eozin and Mallory trichrome staining. Metabolic, histopathologic parameters and cell proliferation showed greater improvement in MetS-PGZ rats and pioglitazone decreased apoptosis of islet cells. Moreover, SVIP, ubiquitin, LC3 and p62 expressions were significantly increased while only p97/VCP expression was significantly decreased in MetS-rat pancreas compared to control. PGZ treatment significantly decreased the MetS-induced increases in autophagy markers. Additionally, UPS and autophagy markers were found to colocalizated with insulin and glucagon. Colocalization ratio of UPS markers with insulin showed significant decrease in MetS rats and PGZ increased this ratio, whereas LC3-insulin colocalization displayed significant increase in MetS rats and PGZ reversed this effect. In conclusion, PGZ improved the pancreatic tissue degeneration by increasing the level of p97/VCP and decreasing autophagic proteins, SVIP and ubiquitin expressions in MetS-rats. Moreover, PGZ has an effect on the colocalization ratio of UPS and autophagy markers with insulin.

  相似文献   
9.
Biological Trace Element Research - Total concentrations of heavy metals such as Cu, Fe, Mn, Ni, and Zn in different hazelnut samples obtained by different regions of Sakarya city, Turkey were...  相似文献   
10.
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