Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Zoolog Sci ; 41(2): 210-215, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38587916

RESUMEN

Protocobitis species are typical cave-dwelling fish, exhibiting distinctive morphological adaptations such as colorless body, lack of eyes, and reduced scales and ribs in response to their extreme cave habitats. Distinct from the recorded species, P. anteroventris, P. polylepis, and P. typhlops, a new species, Protocobitis longicostatus sp. nov., is described from Guangxi Zhuang Autonomous Region, China. Protocobitis longicostatus sp. nov. can easily be distinguished from all known congeners by the following characteristics: whole body covered by scales except head, 12 branched caudal fin rays, and long ribs. These species face threats from habitat degradation, hydrological changes, and environmental pollution. Thus, the conservation of cavefish in China has become an urgent issue.


Asunto(s)
Cipriniformes , Animales , Cipriniformes/anatomía & histología , China , Cuevas , Ojo , Ecosistema
2.
Chaos ; 32(12): 123116, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36587351

RESUMEN

The box-covering method plays a fundamental role in the fractal property recognition and renormalization analysis of complex networks. This study proposes the hub-collision avoidance and leaf-node options (HALO) algorithm. In the box sampling process, a forward sampling rule (for avoiding hub collisions) and a reverse sampling rule (for preferentially selecting leaf nodes) are determined for bidirectional network traversal to reduce the randomness of sampling. In the box selection process, the larger necessary boxes are preferentially selected to join the solution by continuously removing small boxes. The compact-box-burning (CBB) algorithm, the maximum-excluded-mass-burning (MEMB) algorithm, the overlapping-box-covering (OBCA) algorithm, and the algorithm for combining small-box-removal strategy and maximum box sampling with a sampling density of 30 (SM30) are compared with HALO in experiments. Results on nine real networks show that HALO achieves the highest performance score and obtains 11.40%, 7.67%, 2.18%, and 8.19% fewer boxes than the compared algorithms, respectively. The algorithm determinism is significantly improved. The fractal dimensions estimated by covering four standard networks are more accurate. Moreover, different from MEMB or OBCA, HALO is not affected by the tightness of the hubs and exhibits a stable performance in different networks. Finally, the time complexities of HALO and the compared algorithms are all O(N2), which is reasonable and acceptable.


Asunto(s)
Algoritmos , Fractales
3.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(2): 137-41, 2015 Feb.
Artículo en Zh | MEDLINE | ID: mdl-25881455

RESUMEN

OBJECTIVE: To observe the effect of Chuanhuang No.1 Recipe (CHR) on renal function and micro-inflammation in phase 3 chronic kidney disease (CKD) patients. METHODS: Totally 60 phase 3 CKD patients were randomly assigned to the treatment group (treated by CHR) and the control group (treated by Losartan Potassium), 30 in each group. All patients received basic treatment. Patients in the treatment group took CHR decoction, 400 mL each time, one dose per day, while those in the control group took Losartan Potassium, 50-100 mg per day. All medication lasted for 24 weeks. Changes of serum creatinine (SCr), blood urea nitrogen (BUN), estimated glomerular filtration rate (eGFR), serum uric acid (UA), 24 h urinary protein excretion (24 h U-pro), urinary microalbumin (U-Alb), high-sensitivity C-reactive protein (hs-CRP), serum tumor necrosis factor (TNF)-alpha, and serum IL-6 were detected and compared before and after treatment. Efficacy was also compared. RESULTS: Compared with before treatment, SCr and BUN significantly decreased in the treatment group (P<0.05, P<0.01); eGFR in- creased (P<0.05). Only UA obviously decreased in the control group (P<0.05), but with no obvious change in SCr, BUN, or eGFR. Compared with before treatment, 24 h U-pro decreased after treatment in the treatment group (P<0.05), but with less decreased level when compared with the control group. U- Alb was also significantly decreased in the control group (P<0.01). There was statistical difference in 24 h U-pro and U-Alb between the two groups after treatment (P<0.05). Compared with before treatment, hs-CRP obviously decreased after treatment in the two groups, but serum levels of TNF-alpha and IL-6 obviously decreased only in the treatment group (P<0.05). The total effective rate was obviously higher in the treatment group than in the control group (70.00% vs. 43.33%, P<0.01). CONCLUSION: CHR could efficiently improve the renal function of phase 3 CKD patients and alleviate the micro-inflammation.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Renal Crónica/tratamiento farmacológico , Adulto , Nitrógeno de la Urea Sanguínea , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Inflamación , Interleucina-6/metabolismo , Losartán/uso terapéutico , Masculino , Persona de Mediana Edad , Fitoterapia , Factor de Necrosis Tumoral alfa/metabolismo , Urea
4.
Clin Pharmacol Drug Dev ; 13(1): 96-102, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37814913

RESUMEN

This study was designed to compare the beneficial effects of paricalcitol combined with or without cinacalcet on calcium and phosphorus metabolism in patients undergoing maintenance hemodialysis (MHD). A total of 140 patients who received MHD in our hospital from March 2021 to March 2022 were randomly divided into a control group (intravenous paricalcitol, n = 70) and a test group (intravenous paricalcitol combined with oral cinacalcet, n = 70). Clinical baseline data and relevant laboratory parameters before treatment were compared. Additionally, calcium, phosphorus, intact parathyroid hormone in serum were measured and compared between the 2 groups before treatment and 1, 2, 3, 4, 5, 6, 9, 10, and 12 months after treatment. As a result, comparison before treatment demonstrated no significant difference in baseline data such as age, sex, and most laboratory parameters between the 2 groups (P > .05), but there was a significant difference in mean corpuscular volume (P < .001). The serum phosphorus level decreased and calcium level increased significantly in the 2 groups after treatment, while the intact parathyroid hormone level showed no significant change within 12 months of treatment (P > .05). In addition, the combined treatment for 6-12 months caused a much lower phosphorus level (P < .05) and higher calcium level (P < .05) than the treatment with paricalcitol alone, and the difference increased with the extension of treatment time. Collectively, paricalcitol combined with cinacalcet, which is more effective than paricalcitol alone, has a positive effect on calcium and phosphorus metabolism in patients receiving MHD.


Asunto(s)
Calcio , Hiperparatiroidismo Secundario , Humanos , Cinacalcet/uso terapéutico , Calcio/uso terapéutico , Hiperparatiroidismo Secundario/tratamiento farmacológico , Hiperparatiroidismo Secundario/etiología , Diálisis Renal , Hormona Paratiroidea/uso terapéutico , Fósforo
5.
Zookeys ; 1182: 207-221, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37881412

RESUMEN

Formosaniaimmaculata, a new species, is described from the Ou-Jiang basin in Zhejiang Province, Southeast China. It is distinguished from other species of the genus by having a combination of the following characteristics: body without obvious mottling; snout length longer than postorbital length; abdominal scaleless area extending to middle of pectoral-fin base; shorter rostral barbels, the outermost pair length 112.9%-140.0% of eye diameter; and shorter lower lip papillae, length 19.9%-24.4% of eye diameter. Its validity is also affirmed by its distinct Cytb gene sequence divergence from all congeners and its monophyly recovered in a Cytb gene-based phylogenetic analysis.

6.
Zookeys ; 1180: 81-104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37767522

RESUMEN

In this work, a new species of the genus Oreonectes is described, named Oreonectesdamingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov., collected from the Damingshan Mountains of the Guangxi Zhuang Autonomous Region, China. Phylogenetic trees constructed based on the mitochondrial Cyt b showed that the new species represents an independent evolutionary lineage, with uncorrected genetic distances (p-distance) from congeners ranging from 6.1% to 8.9%. Morphologically, the new species can be distinguished from five other species of the genus by a combination of characters. The discovery of this new species raises the number of known species of Oreonectes from five to six. Our study suggests that O.platycephalus may be a complex containing multiple species and that previously recorded areas need to be further delimited and reevaluated.

7.
Zookeys ; 1185: 21-42, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074905

RESUMEN

This work describes a new species, Balitoraanlongensissp. nov., collected from a cave at Xinglong Town, Anlong County, Guzihou, China. Phylogenetic trees reconstructed based on two mitochondrial and three nuclear genes show that the new species represents an independent evolutionary lineage with large genetic differences, 7.1%-12.0% in mitochondrial gene cytochrome b and 9.2%-12.1% in cytochrome oxidase subunit 1, from congeners. Morphologically, the new species can be distinguished from the 18 species currently assigned to the genus Balitora by a combination of characters, most clearly by having two pairs of maxillary barbels; 8½ branched dorsal-fin rays; 5½ branched anal-fin rays; pectoral fin not reaching pelvic fin origin; dorsal-fin origin in front of pelvic fin origin; eye small (eye diameter approximately equal to outer maxillary barbel length); and fins lacking pigment in live fish. The new species represents the first record of Balitora inhabiting caves in China and increases the number of species in the genus Balitora in its present concept from 18 to 19. The study suggests that more evidence is needed to further clarify the taxonomic composition of the genus Balitora.

8.
Zookeys ; 1141: 1-28, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37234961

RESUMEN

Sinocyclocheiluslongicornussp. nov. is described from the Pearl River basin in Hongguo Town, Panzhou City, Guizhou Province, Southwest China. Based on the presence of the long horn-like structure on the back of the head, Sinocyclocheiluslongicornussp. nov. is assigned to the Sinocyclocheilusangularis species group. Sinocyclocheiluslongicornussp. nov. is distinguished from its congeners by a combination of morphological characters: (1) presence of a single, relatively long horn-like structure on the back of the head; (2) pigmentation absent; (3) reduced eyes; (4) dorsal-fin rays, ii, 7; (5) pectoral-fin rays, i, 13; (6) anal-fin rays, iii, 5; (7) pelvic-fin rays, i, 7; (8) lateral line pores 38-49; (9) gill rakers well developed, nine on first gill arch; and (10) tip of adpressed pelvic fin not reaching anus.

9.
Zookeys ; 1185: 43-81, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074912

RESUMEN

Recently described cave species of the genus Triplophysa have been discovered in southwestern China, suggesting that the diversity of the genus is severely underestimated and that there may be many undescribed species. In this work, four new species of the genus Triplophysa are described from southwestern Guizhou Province, China, namely Triplophysacehengensis Luo, Mao, Zhao, Xiao & Zhou, sp. nov. and Triplophysarongduensis Mao, Zhao, Yu, Xiao & Zhou, sp. nov. from Rongdu Town, Ceheng County, Guizhou, Triplophysapanzhouensis Yu, Luo, Lan, Xiao & Zhou, sp. nov. from Hongguo Town, Panzhou City, Guizhou, and Triplophysaanlongensis Song, Luo, Lan, Zhao, Xiao & Zhou, sp. nov. from Xinglong Town, Anlong County, Guizhou. These four new species can be distinguished from all recognized congeners by a combination of morphological characteristics and significant genetic divergences. The discovery of these species increases the number of known cave species within the genus Triplophysa to 39, making the genus the second most diverse group of cave fishes in China after the golden-line fish genus Sinocyclocheilus. Based on the non-monophyletic relationships of the different watershed systems in the phylogenetic tree, this study also discusses the use of cave species of the genus Triplophysa to determine the possible historical connectivity of river systems.

10.
BMC Neurosci ; 13: 154, 2012 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-23272656

RESUMEN

BACKGROUND: There are two widely used transient middle cerebral artery occlusion (MCAO) methods, which differ in the use of unilateral or bilateral carotid artery reperfusion (UNICAR and BICAR). Of the two methods, UNICAR is easier to perform. This study was designed to comprehensively compare the two reperfusion methods to determine if there are any differences in outcomes. RESULTS: The UNICAR and BICAR groups each included 9 rats. At baseline, the average pO(2) was 20.54 ± 9.35 and 26.43 ± 7.39, for the UNICAR and BICAR groups, respectively (P = 0.519). Changes in pO(2), as well as other physiological parameters measured within the ischemic lesion, were similar between the UNICAR and BICAR groups during 90 min of MCAO and the first 30 min of reperfusion (all P > 0.05). Furthermore, both the Bederson score and Garcia score, which are used for neurological assessment, were also similar (both P > 0.05). There were also no significant differences in T2WI lesion volume, DWI lesion volume, PWI lesion volume, or TTC staining infarct volume between the two groups (all P > 0.05). CONCLUSION: UNICAR and BICAR have similar capability for inducing acute brain ischemic injury and can be considered interchangeable up to 24 hours after reperfusion.


Asunto(s)
Circulación Cerebrovascular/fisiología , Infarto de la Arteria Cerebral Media/patología , Daño por Reperfusión/patología , Reperfusión/métodos , Animales , Imagen de Difusión por Resonancia Magnética/métodos , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/mortalidad , Infarto de la Arteria Cerebral Media/fisiopatología , Masculino , Neuroimagen/métodos , Examen Neurológico , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/mortalidad , Daño por Reperfusión/fisiopatología , Índice de Severidad de la Enfermedad , Factores de Tiempo
11.
Zool Res ; 43(5): 787-804, 2022 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-35993131

RESUMEN

The Paramesotriton Chang, 1935 genus of Asian warty newts is the second most diverse genus in the family Salamandridae, currently containing 14 recognized species from northern Vietnam to southwest-central and southern China. Although species of this genus have been included in previous phylogenetic studies, the origin and interspecific relationships of the genus are still not fully resolved, especially at key nodes in the phylogeny. In this study, we sequenced mitochondrial genomes and 32 nuclear genes from 27 samples belonging to 14 species to reconstruct the interspecific phylogenetic relationships within Paramesotriton and explore its historical biogeography in southern China. Both Bayesian inference and maximum-likelihood analyses highly supported the monophyly of Paramesotriton and its two recognized species groups ( P. caudopunctatus and P. chinensis groups) and further identified five hypothetical phylogenetic cryptic species. Biogeographic analyses indicated that Paramesotriton originated in southwestern China (Yunnan-Guizhou Plateau/South China) during the late Oligocene. The time of origin of Paramesotriton corresponded to the second uplift of the Himalayan/Qinghai-Xizang (Tibetan) Plateau (QTP), rapid lateral extrusion of Indochina, and formation of karst landscapes in southwestern China. Principal component analysis (PCA), independent sample t-tests, and niche differentiation using bioclimatic variables based on locations of occurrence suggested that Paramesotriton habitat conditions in the three current regions (West, South, and East) differ significantly, with different levels of climatic niche differentiation. Species distribution model (SDM) predictions indicated that the most suitable distribution areas for the P. caudopunctatus and P. chinensis species groups are western and southern/eastern areas of southern China. This study increases our knowledge of the taxonomy, biodiversity, origin, and suitable distribution areas of the genus Paramesotriton based on phylogenetic, biogeographic, and species distribution models.


Asunto(s)
Genoma Mitocondrial , Animales , Teorema de Bayes , China , Filogenia , Salamandridae/genética
12.
Phytomedicine ; 104: 154241, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35749827

RESUMEN

BACKGROUND: Non-alcoholic steatohepatitis (NASH) has replaced viral hepatitis as the main driver of the rising morbidity and mortality associated with cirrhosis and liver cancer worldwide, while no FDA-approved therapies are currently known. Kinsenoside (KD), naturally isolated from Anoectochilus roxburghii, possesses multiple biological activities, including lipolysis, anti-inflammation, and hepatoprotection. However, the effects of KD on NASH remain unclear. PURPOSE: This study aimed to explore the roles of KD in NASH and its engaged mechanisms. METHODS: Two typical animal models of NASH, mice fed a methionine-choline-deficient (MCD) diet (representing non-obese NASH) and mice fed a high-fat and -fructose diet (HFFD) (representing obese NASH), were used to investigate the effect of KD on NASH in vivo. Transcriptome sequencing was performed to elucidate the underlying mechanisms of KD. Lipopolysaccharide (LPS)-stimulated THP-1 cells and transforming growth factor ß1 (TGF-ß1)-activated LX-2 cells were applied to further explore the effects and mechanisms of KD in vitro. RESULTS: The intragastric administration of KD remarkably alleviated MCD/HFFD-induced murine NASH almost in a dose-dependent manner. Specifically, KD reduced lipid accumulation, inflammation, and fibrosis in the liver of NASH mice. KD ameliorated alanine aminotransferase (ALT), aspartate aminotransferase (AST), superoxide dismutase (SOD), and malondialdehyde (MDA) abnormalities. In addition, it decreased the level of serum proinflammatory factors (IL-12p70, IL-6, TNF-α, MCP-1, IFN-γ) and the hepatic expression of typical fibrosis-related molecules (α-SMA, Col-I, TIMP-1). Mechanically, KD attenuated the MCD/HFFD-induced NASH through the inhibition of the NF-κB/NLRP3 signaling pathway. Consistently, KD reduced inflammation stimulated by LPS in THP-1 cells via suppressing the NF-κB/NLRP3 pathway. Furthermore, it prevented the activation of LX-2 cells directly, by inhibiting the proliferation stimulated by TGF-ß1, and indirectly, by inactivating the NLRP3 inflammasome in macrophages. CONCLUSION: For the first time, the practical improvement of NASH by KD was revealed. Our study found that KD exerted its alleviative effects on NASH through the inhibition of the NF-κB/NLRP3 signaling pathway. Given its hepatoprotective and nontoxic properties, KD has the potential to be a novel and effective drug to treat NASH.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , 4-Butirolactona/análogos & derivados , Animales , Fibrosis , Inflamación/metabolismo , Lipopolisacáridos/farmacología , Hígado , Metionina/metabolismo , Metionina/farmacología , Ratones , Ratones Endogámicos C57BL , Monosacáridos , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta1/metabolismo
13.
Zhong Xi Yi Jie He Xue Bao ; 9(7): 804-7, 2011 Jul.
Artículo en Zh | MEDLINE | ID: mdl-21749833

RESUMEN

OBJECTIVE: To understand the degree of local medical students' clinical practice skills, evaluate teaching achievements and reveal weaknesses by analyzing the test papers and grades, so as to provide scientific advices for reform in clinical education. METHODS: Test papers of 721 copies of traditional Chinese medical qualification examination (practical skills examination) were collected from the examination district of Shanghai in 2009. The papers were analyzed by using the principle and method of teaching statistics. The difficulty and reliability coefficients, discrimination and scores were evaluated. RESULTS: The reliability coefficient of the paper was 0.527, the difficulty coefficients of different parts differed from 0.582 to 0.828 and the discrimination ranged from 0.401 to 0.753. The average score was 75.519 with the standard deviation of 11.073. The examinees had high scores in Chinese medicine training, including acupoint location and methods of acupuncture and moxibustion, but low scores in practice and display of Western medicine. CONCLUSION: The reliability coefficient, discrimination and the difficulty are all preferable. The students got a satisfying average while they had a shortage of ability in practice and display of Western medicine.


Asunto(s)
Educación Médica , Evaluación Educacional , Medicina Tradicional China , Médicos
14.
Mitochondrial DNA B Resour ; 6(12): 3396-3397, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34790873

RESUMEN

This study determined the complete mitochondrial genome of Formosania galericula (Cypriniformes: Gastromyzontidae) from Zhejiang, China, for the first time. The complete mitochondrial genome of F. galericula was sequenced to be 16,555 bp in length. The genome contained 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, two central non-coding regions (the control region and the origin of light strand replication), identical to most other vertebrates. Phylogenetic analysis highly supported that F. galericula was close to Crossostoma lacustre and the genus Vanmanenia fish. However, F. galericula was not firstly clustered with Formosania chenyiyui but after the genus Vanmanenia fish. These data would explain the evolutionary mechanisms and biogeography of the family Gastromyzontidae and is helpful for the conservation of genetics and stock evaluation for F. galericula.

15.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 39(6): 644-9, 2010 11.
Artículo en Zh | MEDLINE | ID: mdl-21166061

RESUMEN

Hydrocephalus is a common medical condition characterized by abnormalities in the secretion,circulation or resorption of cerebrospinal fluid (CSF), resulting in ventricular dilatation. The pathogenetic mechanism for the hydrocephalus is attributed to: the overproduction of CSF by the choroid plexus; the defect in CSF absorption and obstruction of CSF flow in the cerebral ventricles. However, the underlying etiology is poorly understood. With the development of genetic engineering, a growing body of evidence indicates that genetic factors play an essential role in the pathogenesis of hydrocephalus. It is the aim of this review to summarize these findings.


Asunto(s)
Hidrocefalia/genética , Hidrocefalia/patología , Animales , Ventrículos Cerebrales/patología , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados
16.
PhytoKeys ; 157: 145-153, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32943977

RESUMEN

Didymocarpus lobulatus, a new species endemic to Zhejiang province, eastern China, is described and illustrated with photographs. The new species is morphologically similar to D. heucherifolius, D. cortusifolius and D. salviiflorus in leaf morphology, but can be easily distinguished by a combination of characters, including the shape of bracts, calyx and calyx lobes.

17.
Medicine (Baltimore) ; 99(46): e23229, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33181709

RESUMEN

BACKGROUND: Uremic pruritus (UP) is a common and tormenting symptom in end-stage renal disease patients undergoing maintenance hemodialysis. An increasing number of studies have been published in recent years to support the effectiveness of montelukast for UP. We will conduct a comprehensive systematic review and meta-analysis to evaluate effectiveness of montelukast for UP in hemodialysis patients. METHODS: The following electronic databases were searched: Pubmed, Embase, Web of Science, Cochrane Library, the China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and China Science and Technology Journal Database. The range of publication time was from the inception of the database to December 2020. Two reviewers will independently conduct article selection, data collection, and assessment of risk of bias. Any disagreement will be resolved by discussion with the third reviewer. Meta-analysis will be performed by Review Manager 5.3. The Cochrane Collaboration tool will be used to assess the risk of bias. RESULTS: This study will provide a systematic synthesis of current published data to explore the effectiveness of montelukast for UP in hemodialysis patients. CONCLUSIONS: This systematic review and meta-analysis will provide clinical evidence for the effectiveness of montelukast for UP in hemodialysis patients and inform our understanding of the value of montelukast in improving pruritus symptoms. This study will help clinicians, patients, and policy makers to make better decisions regarding the appropriate role of montelukast as a part of patient management routines. STUDY REGISTRATION NUMBER: INPLASY2020100043.


Asunto(s)
Acetatos/uso terapéutico , Protocolos Clínicos , Prurito/tratamiento farmacológico , Quinolinas/uso terapéutico , Ciclopropanos , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/tratamiento farmacológico , Antagonistas de Leucotrieno/uso terapéutico , Metaanálisis como Asunto , Prurito/fisiopatología , Diálisis Renal/métodos , Sulfuros , Revisiones Sistemáticas como Asunto
18.
Virus Evol ; 6(1): veaa020, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32296543

RESUMEN

Epizootic pathogens pose a major threat to many wildlife species, particularly in the context of rapidly changing environments. Pangolins (order Pholidota) are highly threatened mammals, in large part due to the trade in illegal wildlife. During July to August 2018 four sick wild pangolins (three Manis javanica and one Manis pentadactyla) exhibiting a variety of clinical symptoms were rescued by the Jinhua Wildlife Protection Station in Zhejiang province, China. Although three of these animals died, fortunately one recovered after 2 weeks of symptomatic treatment. Using meta-transcriptomics combined with reverse transcription polymerase chain reaction (RT-PCR), we identified two novel RNA viruses in two of the dead pangolins. Genomic analysis revealed that these viruses were most closely related to pestiviruses and coltiviruses, although still highly genetically distinct, with more than 48 and 25 per cent sequence divergence at the amino acid level, respectively. We named these Dongyang pangolin virus (DYPV) and Lishui pangolin virus (LSPV) based on the sampling site and hosts. Although coltiviruses (LSPV) are known to be transmitted by ticks, we found no evidence of LSPV in ticks sampled close to where the pangolins were collected. In addition, although DYPV was present in nymph ticks (Amblyomma javanense) collected from a diseased pangolin, they were not found in the local tick population. Epidemiological investigation revealed that both novel viruses might have been imported following the illegal international trade of pangolins. Hence, these data indicate that illegal wildlife trafficking not only threatens the status of pangolin populations, but may also spread epizootic pathogens.

20.
ACS Appl Mater Interfaces ; 10(43): 37298-37306, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30339350

RESUMEN

Driven by an ever-growing demand for environmentally compatible materials, the past two decades have witnessed the booming development in the field of piezoelectrics. To maximally explore the potential of lead-free piezoelectrics, chemical doping could be an effective approach, referenced from tactics adopted in lead-based piezoelectrics. Herein, we reveal the distinct role of manganese in a promising lead-free perovskite (K, Na)NbO3 (denoted by KNN) in comparison to that in market-dominating lead-based counterparts [Pb(Zr, Ti)O3, PZT]. In contrast to the scenario in PZT, manganese doping in KNN results in tremendously improved piezoelectric coefficient d33 by nearly 200%, whereas the same doping species in PZT deteriorates the d33 down to less than 30% of its original value. The result is rationalized from macroscopic and local electrical characterizations down to atomic-scale visualization. This study demonstrates that there is enormous space to further enhance piezoelectricity in lead-free systems because the chemical doping effect may completely differ in lead-containing and lead-free perovskites.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA