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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.
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   
3.
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   
4.
5.
CLTOAB is an ammonium-based ionic liquid composed of ε-Caprolactam (CL) C6H11NO and tetraoctylammonium bromide (TOAB) (C32H68BrN). In this study, experimental IR and Raman spectra of CLTOAB ionic liquid together with the computational results of the compound have been reported. The optimized geometry, vibrational frequencies, IR intensities and Raman activities of the CLTOAB were calculated using the wb97xd and B3LYP density functional methods combined with the 6-31G(d,p) basis set using Gaussian 03 program. The complete assignment of the bands was performed based on the potential energy distributions (PED%). The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. The Gauge-including atomic orbital 1H-NMR and 13C-NMR chemical shifts calculations were carried out and compared with the experimental data. Furthermore to evaluate interaction between CLTOAB and DNA, molecular docking study was carried out.

Communicated by Ramaswamy H. Sarma  相似文献   

6.
Isolated ACTH deficiency is an uncommon cause of secondary adrenocortical insufficiency and accompaniment with primary empty sella has been reported in several cases. We present a case of isolated ACTH deficiency associated with empty sella. A sixty-two year old woman was admitted to our endocrine clinic with complaints of weakness, fatigue, weight loss, nausea, vomiting, and lack of appetite for about one month. Physical examination indicated orthostatic hypotension and epigastric tenderness. Laboratory investigations revealed hypoglycemia, hyponatremia and anemia, in addition low plasma cortisole and ACTH levels. Serum cortisole responses to short and prolonged ACTH stimulation were tested and partial and accurate responses were obtained, respectively. Plasma ACTH and serum cortisole levels failed to respond after intravenous injection of human corticotropin releasing hormone. Other hypophysial hormone levels were within the normal reference ranges. Although cranial and abdominal computerized tomography images were evaluated as normal, cranial magnetic resonance imaging of the pituitary gland revealed 'primary empty sella turcica'. Replacement therapy with methylprednisolon resulted in the improvement of hypoglycemia, hyponatremia and clinical symptoms. Based on these results, the patient was diagnosed as isolated ACTH deficiency and was scheduled for follow up by our outpatient clinic. Our report is consistent with other reports pointing out that primary empty sella may be responsible for pathogenesis of isolated ACTH deficiency.  相似文献   
7.
Introduced species offer unique opportunities to study evolution in new environments, and some provide opportunities for understanding the mechanisms underlying macroecological patterns. We sought to determine how introduction history impacted genetic diversity and differentiation of the house sparrow (Passer domesticus), one of the most broadly distributed bird species. We screened eight microsatellite loci in 316 individuals from 16 locations in the native and introduced ranges. Significant population structure occurred between native than introduced house sparrows. Introduced house sparrows were distinguished into one North American group and a highly differentiated Kenyan group. Genetic differentiation estimates identified a high magnitude of differentiation between Kenya and all other populations, but demonstrated that European and North American samples were differentiated too. Our results support previous claims that introduced North American populations likely had few source populations, and indicate house sparrows established populations after introduction. Genetic diversity also differed among native, introduced North American, and Kenyan populations with Kenyan birds being least diverse. In some cases, house sparrow populations appeared to maintain or recover genetic diversity relatively rapidly after range expansion (<50 years; Mexico and Panama), but in others (Kenya) the effect of introduction persisted over the same period. In both native and introduced populations, genetic diversity exhibited large-scale geographic patterns, increasing towards the equator. Such patterns of genetic diversity are concordant with two previously described models of genetic diversity, the latitudinal model and the species diversity model.  相似文献   
8.
目的:从新疆块根芍药(Paeonia anomala)内生菌中筛选出1株对植物病原菌有抑菌活性的内生菌并对其进行鉴定及特性分析.方法:采用琼脂扩散法进行抑菌实验,基于形态特征,生理生化特性,16S rDNA序列分析并G+C mol%含量对XJU-PA-1进行鉴定.结果:XJU-PA-1对玉米小班病菌和苹果半点落叶病菌有抑菌活性,抑菌圈直径都超过20mm.XJU-PA-1与DQ010109 Bacillus subtilis的16S rDNA序列的同源性达到100%,G+Cmol%含量为54.5%.结论:XJU-PA-1对两种致病菌有较强的抑菌能力,被鉴定为枯草芽孢杆菌(Bacillus subtilis) ,在GenBank数据库的注册号为EU741698.  相似文献   
9.
Background: Helicobacter pylori infection is a most frequent cause of chronic gastritis. H. pylori may decrease absorption of oral thyroxine by decreasing gastric acid secretion in the stomach. In this study, we aimed to investigate the change in thyroid function tests of the cases after H. pylori eradication who were not responding to high doses of thyroxine treatment before H. pylori eradication. Methods: Hypothyroid cases who were not responding to high doses of thyroxine among the ones presented to Endocrinology and Gastroenterohepatology Clinics of Sisli Etfal Training and Research Hospital between 2009 and 2010 were included in the study. Thyroid function tests were performed two times in all cases before and after H. pylori eradication. Duodenal, antral and corporal biopsies, and jejunal aspirates and biopsies were taken during upper gastrointestinal system endoscopies performed in all patients. Cases without intestinal pathology were included in the study. Results: Serum thyrotropin (TSH), free T3, and free T4 values before H. pylori eradication were 30.5 ± 28.8 IU/mL, 2.64 ± 0.56 pg/mL, and 0.92 ± 0.32 ng/mL, respectively, and after eradication were found to be 4.2 ± 10.6 IU/mL, 3.02 ± 0.61 pg/mL, and 1.3 ± 0.34 ng/mL, respectively (p values <.001, .002, and <.001, respectively). After H. pylori eradication treatment, TSH decreased in all of the cases, factitious thyrotoxicosis developed in % 21 of these cases. Conclusion: In hypothyroid cases, H. pylori gastritis may be responsible for an inadequate response to the treatment. H. pylori eradication in the cases receiving high doses of thyroxine has a risk for thyrotoxicosis.  相似文献   
10.
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