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1.
Sci Rep ; 14(1): 2745, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38302507

RESUMO

The objective of this study was to analyze the antimicrobial resistance (AMR) characteristics produced by antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and gene cassettes in Escherichia coli isolated from the feces of captive black bears. Antimicrobial susceptibility testing was performed by using the disk diffusion method, and both MGEs and integron gene cassettes were detected by polymerase chain reaction. Our results showed that 43.7% (62/142) of the isolates were multidrug resistant strains and 97.9% (139/142) of the isolates were resistant to at least one antibiotic. The highest AMR phenotype was observed for tetracycline (79.6%, 113/142), followed by ampicillin (50.0%, 71/142), trimethoprim-sulfamethoxazole (43.7%, 62/142) and cefotaxime (35.9%, 51/142). However, all isolates were susceptible to tobramycin. tetA had the highest occurrence in 6 ARGs in 142 E. coli isolates (76.8%, 109/142). Ten mobile genetic elements were observed and IS26 was dominant (88.0%, 125/142). ISECP1 was positively associated with five ß-lactam antibiotics. ISCR3/14, IS1133 and intI3 were not detected. Seventy-five E. coli isolates (65 intI1-positive isolates, 2 intI2-positive isolates and 8 intI1 + intI2-positive isolates) carried integrons. Five gene cassettes (dfrA1, aadA2, dfrA17-aadA5, aadA2-dfrA12 and dfrA1-aadA1) were identified in the intI1-positive isolates and 2 gene cassettes (dfrA1-catB2-sat2-aadA1 and dfrA1-catB2-sat1-aadA1) were observed in the intI2-positive isolates. Monitoring of ARGs, MGEs and gene cassettes is important to understand the prevalence of AMR, which may help to introduce measures to prevent and control of AMR in E. coli for captive black bears.


Assuntos
Escherichia coli , Ursidae , Animais , Antibacterianos/farmacologia , Ursidae/genética , Farmacorresistência Bacteriana/genética , Integrons/genética
2.
PLoS One ; 18(11): e0289028, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38011149

RESUMO

This study aimed to investigate the antimicrobial resistance (AMR), antibiotic resistance genes (ARGs) and integrons in 157 Escherichia coli (E. coli) strains isolated from feces of captive musk deer from 2 farms (Dujiang Yan and Barkam) in Sichuan province. Result showed that 91.72% (144/157) strains were resistant to at least one antimicrobial and 24.20% (38/157) strains were multi-drug resistant (MDR). The antibiotics that most E. coli strains were resistant to was sulfamethoxazole (85.99%), followed by ampicillin (26.11%) and tetracycline (24.84%). We further detected 13 ARGs in the 157 E. coli strains, of which blaTEM had the highest occurrence (91.72%), followed by aac(3')-Iid (60.51%) and blaCTX-M (16.56%). Doxycycline, chloramphenicol, and ceftriaxone resistance were strongly correlated with the presence of tetB, floR and blaCTX-M, respectively. The strongest positive association among AMR phenotypes was ampicillin/cefuroxime sodium (OR, 828.000). The strongest positive association among 16 pairs of ARGs was sul1/floR (OR, 21.667). Nine pairs positive associations were observed between AMR phenotypes and corresponding resistance genes and the strongest association was observed for CHL/floR (OR, 301.167). Investigation of integrons revealed intl1 and intl2 genes were detected in 10.19% (16/157) and 1.27% (2/157) E. coli strains, respectively. Only one type of gene cassettes (drA17-aadA5) was detected in class 1 integron positive strains. Our data implied musk deer is a reservoir of ARGs and positive associations were common observed among E. coli strains carrying AMRs and ARGs.


Assuntos
Anti-Infecciosos , Cervos , Infecções por Escherichia coli , Animais , Antibacterianos/farmacologia , Escherichia coli , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/veterinária , Farmacorresistência Bacteriana/genética , Ampicilina , China , Ruminantes , Integrons/genética , Testes de Sensibilidade Microbiana
3.
PhytoKeys ; 230: 145-156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37588038

RESUMO

Thrixspermumtaeniophyllum is described as a new orchid species from Wenchuan County, Sichuan Province of southwest China. It is morphologically similar to T.japonicum, but it differs from the latter in having branched stems, slightly fleshy strap-shaped leaves, longer inflorescences with 3-6 flowers and a capitate gynandrium with a lip-shaped mouth opening. Its species status is also supported by molecular phylogenetic analyses, based on nuclear ribosome internal transcribed spacer (nrITS) and three chloroplast DNA fragments (matK, psbA-trnH and trnL-F), which showed distinct systematic boundaries from the most morphologically similar T.japonicum and their morphological relatives T.saruwatarii and T.pygmaeum.

4.
Biology (Basel) ; 12(4)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37106710

RESUMO

The umbrella-species strategy has been proposed as an attainable tool to achieve multi-species and community conservation with limited investment. There have been many umbrella-related studies since the concept's inception; thus, a summary of global study efforts and recommended umbrella species is important for understanding advances in the field and facilitating conservation applications. Here, we collated 213 recommended umbrella species of terrestrial vertebrates from 242 scientific articles published during 1984-2021 and analyzed their geographic patterns, biological features, and conservation statuses to identify global trends in the selection of umbrella species. We found a considerable geographic bias: most studies and, consequently, recommended umbrella species are from the Northern Hemisphere. There is also a strong taxonomic bias, with grouses (order Galliformes) and large carnivores being the most popular umbrella species and amphibians and reptiles being largely overlooked. In addition, wide-ranging and non-threatened species were frequently recommended as umbrella species. Given the observed biases and trends, we caution that appropriate species need to be chosen for each location, and it is important to confirm that popular, wide-ranging species are effective umbrella species. Moreover, amphibians and reptiles should be investigated for their potential as umbrella species. The umbrella-species strategy has many strengths and, if applied appropriately, may be one of the best options in today's conservation research and funding landscape.

5.
PhytoKeys ; 218: 47-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762277

RESUMO

This paper describes and illustrates a new species of Primulaceae, Primulawolongensis sp. nov. from Wolong National Nature Reserve in Sichuan Province, China. It is very rare and currently only known from its type locality. The new species belongs to subsection Chartacea of the section Petiolares on account of lacking bud scales at flowering, being efarinose and having distinct petiolate leaves with more or less rounded lamina. The new species can be differentiated from other members of the subsection by leaf blade margin dentate, and leaf veins which are not raised, scape shorter than or equal to pedicels, yellow flowers and location of stamens of the corolla tube at thrum flower. Molecular phylogenetic analysis based on nuclear ribosome internal transcribed spacer (nrITS) demonstrated that P.wolongensis was sister to subgen. Auriculastrum. Primulawolongensis is currently known from a single location in Wolong Town, and its conservation status is assessed as Data Deficient (DD).

6.
Front Plant Sci ; 13: 911702, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812969

RESUMO

The species in the genus Cypripedium (Orchidaceae) are considered endangered, mainly distributed in the temperate regions of the Northern Hemisphere, with high ornamental and economic value. Despite previous extensive studies based on both morphology and molecular data, species and sections relationships within Cypripedium remain controversial. Here, we employed two newly generated Cypripedium chloroplast genomes with five other published genomes to elucidate their genomic characteristics. The two genomes were 162,773-207,142 bp in length and contained 128-130 genes, including 82-84 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. We identified 2,192 simple sequence repeats, 786 large repeat sequences, and 7,929 variable loci. The increase of repeat sequences (simple sequence repeats and large repeat sequences) causes a significant amplification in the chloroplast genome size of Cypripedium. The expansion of the IR region led to the pseudogenization or loss of genes in the SSC region. In addition, we identified 12 highly polymorphic loci (Pi > 0.09) suitable for inferring the phylogeny of Cypripedium species. Based on data sets of whole chloroplast genomes (IRa excluded) and protein-coding sequences, a well-supported phylogenetic tree was reconstructed, strongly supporting the five subfamilies of Orchidaceae and the genus Cypripedium as monophyletic taxa. Our findings also supported that C. palangshanense belonged to sect. Palangshanensia rather than sect. Retinervia. This study also enriched the genomic resources of Cypripedium, which may help to promote the conservation efforts of these endangered species.

7.
PhytoKeys ; 215: 95-106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761093

RESUMO

Gastrochilusheminii (Orchidaceae), a new orchid species from Sichuan Province, Southwest China, is described and illustrated. It morphologically resembles G.affinis and G.yei, but differs markedly from the former in having a thinner and slightly rolled downwards reniform epichile and the central thickened purple-red mat with irregular folds (vs. subtriangular epichile curves upwards, with 2 thick, brown to purplish-brown median ridges from base to apex), and can be clearly distinguished from the latter by having reniform epichile with lobed apex and subconical hypochile with bilobed apex that splits into two conical protrusions (vs. semi-rounded epichile not lobed and subconical hypochile not bilobed). The results of molecular phylogenetic analysis based on nuclear ribosome internal transcribed spacer (nrITS) and four chloroplast DNA fragments (matK, psbA-trnH, psbM-trnD, and trnL-F) of 36 Gastrochilus species showed that G.heminii was closely related to G.affinis and G.distichus.

8.
PhytoKeys ; 215: 27-36, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761098

RESUMO

The taxonomy of the Sino-Himalayan alpine bamboos is controversial due to their complex evolutionary history and further complicated by the scarcity of inflorescence. Here, we supplement the description of the inflorescence of Fargesiaangustissima T.P. Yi and Yushaniapauciramificans T.P. Yi, which shed light on the taxonomy of Fargesia Franchet, Borinda Stapleton and Yushania Keng. F.angustissima has compressed inflorescence unilateral stretching out from reduced spathe, showing a transitional state between species with condensed inflorescence embraced by spathe-like bracts and species with open inflorescence without bracts. Considering that extensive gene flow existed between several clades of Fargesia found in recent studies, a broadly-defined Fargesia s. l. should be adopted. Meanwhile, the inflorescence of Y.pauciramificans has typical characteristics of Yushania, such as axilla with tuberculate glands, rachilla internodes ciliate and cylindrical florets, supporting the delimitation of Yushania.

9.
Parasite ; 28: 73, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34706216

RESUMO

Blastocystis is a prevalent eukaryotic parasite that has been identified in a wide range of hosts. Several species are considered potential sources of Blastocystis infection in humans, but little is known about the prevalence of Blastocystis in wild animals. In this study, the prevalence and subtypes of Blastocystis were investigated to assess the zoonotic potential of wild animals in Sichuan Wolong National Natural Reserve. A total of 300 fecal samples were collected from 27 wildlife species in three areas of the Reserve. The subtype (ST), genetic characteristics, and prevalence of Blastocystis were determined by PCR amplification of part (~600 bp) of the SSU rRNA gene. Thirty fecal samples (10.0%) were Blastocystis-positive. The highest prevalence of Blastocystis was found in Yinchanggou (18.3%), with significantly less found in Niutoushan (7.5%) and Genda (5.5%) (p < 0.05). No significant differences were associated with different orders of animals in prevalence, which may be because of the small number of positive samples obtained. Sequence analysis showed five subtypes (ST1, ST3, ST5, ST13, and ST14), with ST13 and ST14 being predominant (33% each), followed by ST1 (20%). This is the first molecular investigation of Blastocystis infection in the wild animals of southwestern China. Subtypes ST1, ST3, ST5, and ST14 have previously been identified in humans, suggesting that wild animals may be potential reservoirs of Blastocystis for humans.


TITLE: Caractérisation génétique et potentiel zoonotique de Blastocystis provenant d'animaux sauvages dans la réserve naturelle nationale du Sichuan Wolong, sud-ouest de la Chine. ABSTRACT: Blastocystis est un parasite eucaryote répandu qui a été identifié dans un large éventail d'hôtes. Plusieurs espèces sont considérées comme des sources potentielles d'infection par Blastocystis chez l'homme, mais on sait peu de choses sur la prévalence de Blastocystis chez les animaux sauvages. Dans cette étude, la prévalence et les sous-types de Blastocystis ont été étudiés pour évaluer le potentiel zoonotique des animaux sauvages dans la réserve naturelle nationale du Sichuan Wolong. Au total, 300 échantillons de matières fécales ont été prélevés de 27 espèces de la faune dans trois zones de la réserve. Le sous-type (ST), les caractéristiques génétiques et la prévalence de Blastocystis ont été déterminés par amplification PCR d'une partie (~ 600 pb) du gène 18S de l'ARNr. Trente échantillons fécaux (10,0 %) étaient positifs pour Blastocystis. La prévalence la plus élevée de Blastocystis a été trouvée à Yinchanggou (18,3 %), avec une prévalence significativement moindre à Niutoushan (7,5 %) et à Genda (5,5 %) (p < 0,05). Aucune différence significative de prévalence n'était associée à différents ordres d'animaux, ce qui peut être dû au petit nombre d'échantillons positifs obtenus. L'analyse des séquences a montré cinq sous-types (ST1, ST3, ST5, ST13 et ST14), et ST13 et ST14 étant prédominants (33 % chacun), suivis de ST1 (20 %). Il s'agit de la première étude moléculaire de l'infection à Blastocystis chez les animaux sauvages du sud-ouest de la Chine. Les sous-types ST1, ST3, ST5 et ST14 ont déjà été identifiés chez l'homme, suggérant que les animaux sauvages pourraient être des réservoirs potentiels de Blastocystis pour l'homme.


Assuntos
Infecções por Blastocystis , Blastocystis , Animais , Animais Selvagens , Blastocystis/genética , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/veterinária , China/epidemiologia , Fezes , Variação Genética , Humanos , Filogenia , Prevalência
10.
Asian Pac J Cancer Prev ; 15(11): 4567-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24969886

RESUMO

BACKGROUND: This systemic analysis was conducted to evaluate the efficacy and safety of pemetrexed based chemotherapy in treating patients with metastatic breast cancer as first or second line chemotherapy. METHODS: Clinical studies evaluating the efficacy and safety of pemetrexed based regimens on response and safety for patients with breast cancer were identified using a predefined search strategy. Pooled response rate (RR) of treatment were calculated. RESULTS: In first line pemetrexed based regimens, 10 clinical studies which including 513 patients with advanced breast cancer were considered eligible for inclusion. For second line pemetrexed based chemotherapy, 5 clinical studies which including 281 patients with advanced breast cancer were considered eligible. Systemic analysis suggested that, in all patients, pooled RR was 32.6% (167/513) in pemetrexed based first line regimens, and 13.9 % (39/281) in pemetrexed based second line regimens. Major adverse effects were neutropenia, leukopenia, fatigue, and anemia in pemetrexed based first line treatment; and lymphopenia, neutropenia, leukopenia, as well as anemia in second line chemotherapy. One treatment related death occurred with pemetrexed based second line treatment. CONCLUSION: This systemic analysis suggests that pemetrexed based first line regimens are associated with a reasonable response rate and acceptable toxicity, however with low response rate for treating patients with metastatic breast cancer when is used in the second line.


Assuntos
Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Glutamatos/efeitos adversos , Glutamatos/uso terapêutico , Guanina/análogos & derivados , Feminino , Guanina/efeitos adversos , Guanina/uso terapêutico , Humanos , Pemetrexede
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