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1.
Elife ; 122023 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-36930206

RESUMEN

Defensive behaviors are critical for animal's survival. Both the paraventricular nucleus of the hypothalamus (PVN) and the parabrachial nucleus (PBN) have been shown to be involved in defensive behaviors. However, whether there are direct connections between them to mediate defensive behaviors remains unclear. Here, by retrograde and anterograde tracing, we uncover that cholecystokinin (CCK)-expressing neurons in the lateral PBN (LPBCCK) directly project to the PVN. By in vivo fiber photometry recording, we find that LPBCCK neurons actively respond to various threat stimuli. Selective photoactivation of LPBCCK neurons promotes aversion and defensive behaviors. Conversely, photoinhibition of LPBCCK neurons attenuates rat or looming stimuli-induced flight responses. Optogenetic activation of LPBCCK axon terminals within the PVN or PVN glutamatergic neurons promotes defensive behaviors. Whereas chemogenetic and pharmacological inhibition of local PVN neurons prevent LPBCCK-PVN pathway activation-driven flight responses. These data suggest that LPBCCK neurons recruit downstream PVN neurons to actively engage in flight responses. Our study identifies a previously unrecognized role for the LPBCCK-PVN pathway in controlling defensive behaviors.


Asunto(s)
Hipotálamo , Núcleos Parabraquiales , Ratas , Animales , Hipotálamo/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Colecistoquinina/metabolismo , Neuronas/fisiología , Núcleos Parabraquiales/fisiología
2.
Arch Virol ; 168(3): 86, 2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36773166

RESUMEN

A new positive-strand RNA virus was discovered in a horse nettle plant, using high-throughput sequencing (HTS), and its complete genome, consisting of RNA1 and RNA2, which are 7522 and 4710 nucleotides in length, respectively, was characterized. Each genome segment contains a single open reading frame flanked by 5' and 3' untranslated regions (UTRs), followed by a poly(A) tail at the 3' end. The encoded proteins have the highest amino acid sequence identity (55% and 45%) to the polyprotein encoded by RNA1 of tomato black ring virus (TBRV) and RNA2 of potato virus B (PVB), respectively. Its genome organization and phylogenetic relationship to other nepoviruses suggested that this virus is a novel member of subgroup B, and recombination analysis revealed its evolutionary history within the subgroup. These results suggest the new virus, provisionally named "horse nettle virus A", represents a new species within the genus Nepovirus.


Asunto(s)
Nepovirus , Solanum , Nepovirus/genética , Filogenia , ARN Viral/genética , ARN Viral/química , Secuencia de Aminoácidos , Genoma Viral
3.
Biomater Sci ; 10(1): 243-257, 2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-34846385

RESUMEN

Arsenic trioxide (ATO, As2O3), an active ingredient of traditional Chinese medicine, has been approved by the U.S. Food and Drug Administration as an effective therapeutic agent for acute promyelocytic leukemia (APL). However, the application of ATO in treating advanced solid tumors like hepatocellular carcinoma (HCC) is still restricted by limited therapeutic efficacy and insufferable side effects. To solve this problem, we reported a general and facile strategy using human serum albumin (HSA) as a template for synthesizing a series of ATO-based nanoparticles with uniform single-albumin size. Then, we prepared a multifunctional drug delivery system (MDDS) based on MnAs/HSA termed MnAs/ICG/HSA-RGD, and tested its efficacy both in vitro and in vivo. Our results revealed that the photothermal effect of MnAs/ICG/HSA-RGD can not only cause irreversible damage to the tumor but also accelerate the discharge of As and Mn2+ ions, enabling responsive chemotherapy and magnetic resonance imaging. Interestingly, the expression of HSP90, vimentin, and MMP-9 in tumor cells was inhibited during the treatment, resulting in less metastasis and recurrence. Moreover, no apparent side effect has been observed during the treatment. Therefore, MnAs/ICG/HSA-RGD can be considered as a promising option for HCC with excellent therapeutic efficacy and minimum side effects.


Asunto(s)
Arsenitos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Terapia Fototérmica , Albúmina Sérica Humana
4.
Arch Virol ; 166(10): 2869-2873, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34292373

RESUMEN

Eriophyid mites are commonly found on the leaf surface of different plant species. In the present study, a novel virus associated with an eriophyid mite species was detected using high-throughput sequencing (HTS) of total RNA from fruit tree leaves, primarily growing under greenhouse conditions. The complete genome sequence was characterized using rapid amplification of cDNA ends followed by Sanger sequencing, revealing a genome of 8885 nucleotides in length. The single positive-stranded RNA genome was predicted to encode typical conserved domains of members of the genus Iflavirus in the family Iflaviridae. Phylogenetic analysis showed this virus to be closely related to the unclassified iflavirus tomato matilda associated virus (TMaV), with a maximum amino acid sequence identity of 59% in the RNA-dependent RNA polymerase domain. This low identity value justifies the recognition of the novel virus as a potential novel iflavirus. In addition to a lack of graft-transmissibility evidence, RT-PCR and HTS detection of this virus in the putative host plants were not consistent through different years and growing seasons, raising the possibility that rather than a plant virus, this was a virus infecting an organism associated with fruit tree leaves. Identification of Tetra pinnatifidae HTS-derived contigs in all fruit tree samples carrying the novel virus suggested this mite as the most likely host of the new virus (p-value < 1e-11), which is tentatively named "eriophyid mite-associated virus" (EMaV). This study highlights the importance of a careful biological study before assigning a new virus to a particular plant host when using metagenomics data.


Asunto(s)
Frutas/parasitología , Ácaros/virología , Virus ARN Monocatenarios Positivos/clasificación , Árboles/parasitología , Secuencia de Aminoácidos , Animales , Frutas/virología , Genoma Viral/genética , Metagenómica , Filogenia , Extractos Vegetales , Hojas de la Planta/parasitología , Hojas de la Planta/virología , Virus ARN Monocatenarios Positivos/genética , ARN Viral/genética , ARN Polimerasa Dependiente del ARN , Árboles/virología
5.
J Ethnopharmacol ; 237: 307-313, 2019 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-30910581

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Angong Niuhuang Pill (ANP) is a well-known traditional Chinese patent medicine. This meta-analysis aimed to evaluate the efficacy and safety of ANP as an adjuvant therapy in patients with acute cerebral infarction (ACI) and acute intracerebral hemorrhage (AIH). MATERIALS AND METHODS: We performed a literature search in Embase, Pubmed, Cochrane Library, CNKI, Wanfang, and VIP database from their inceptions to April 2018. Randomized controlled trials evaluating ANP as an adjuvant therapy for acute stroke were selected. Risk ratio (RR) or weighted mean difference (WMD) with their 95% confidence interval (CI) was calculated between with and without ANP therapy. RESULTS: Eighteen trials involving 1,601 patients were identified and analyzed. Meta-analysis showed that ANP plus usual treatment significantly improved the total response rate in patients with ACI (RR 1.27; 95% CI 1.14-1.41) and AIH (RR 1.26; 95% CI 1.14-1.38) compared with the usual treatment alone. Adjuvant treatment with ANP also significantly reduced the neurologic deficit score in patients with ACI (WMD -3.64; 95% CI -4.97 to - 2.31) and AIH (WMD -3.52; 95% CI -5.51 to -1.54). Moreover, ANP significantly improved the Glasgow Coma Scale in patients with ACI (WMD 1.18; 95% CI 0.79-1.56) and AIH (WMD 2.28; 95% CI 1.37-3.19). CONCLUSIONS: Adjuvant treatment with ANP appears to improve the total response rate and neurologic deficit score in patients with ACI and AIH. More well-designed trials are required due to the suboptimal methodological quality of the included trials.


Asunto(s)
Hemorragia Cerebral/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
J Agric Food Chem ; 61(7): 1501-8, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23360233

RESUMEN

Peroxidase extracted from Momordica charantia catalyzed the H(2)O(2)-dependent oxidative coupling of 7-hydroxy-4-methylcoumarin to form four new dimers (1-4) and two known ones (5, 6). The structures, including the absolute configurations of axially chiral compounds, were unambiguously characterized by NMR spectroscopy, online HPLC-CD, and a variety of computational methods. Bioactive experiments demonstrated that compounds 1 and 2 had significant inhibitory effects on yeast α-glucosidase, much better than the controls. Noncompetitive binding mode was found by the graphical analysis of steady-state inhibition data. The mechanism of enzymatic inhibition confirmed in some depth that the inhibitors altered the secondary structure of α-glucosidase by decreasing the α-helix and increasing the ß-sheet content. In summary, bicoumarins 1 and 2 might be exploited as the lead compounds for further research of antidiabetic agents, and this research provided a "green" method to synthesize compounds with the chiral biaryl axis generally calling for multistep reactions in organic chemistry.


Asunto(s)
Cumarinas/química , Inhibidores Enzimáticos/química , Inhibidores de Glicósido Hidrolasas , Momordica charantia/enzimología , Peroxidasa/metabolismo , Extractos Vegetales/química , Biotransformación , Catálisis , Cromatografía Líquida de Alta Presión , Cumarinas/análisis , Inhibidores Enzimáticos/análisis , Peróxido de Hidrógeno/química , Espectroscopía de Resonancia Magnética , Extractos Vegetales/análisis , alfa-Glucosidasas/metabolismo
7.
Bull Environ Contam Toxicol ; 88(4): 623-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22286610

RESUMEN

A field study was conducted to evaluate the phytoremediation efficiency of cadmium (Cd) contaminated soil utilizing the Cd hyperaccumulator Beta vulgaris L. var. cicla during one growing season (about 2 months) on farmland in Zhangshi Irrigation Area, the representative wastewater irrigation area in China. Results showed that B. vulgaris L. var. cicla is a promising plant in the phytoremediation of Cd contaminated farmland soil. The maximum of Cd phytoremediation efficiency by B. vulgaris L. var. cicla reached 144.6 mg/ha during one growing season. Planting density had a significant effect on the plant biomass and the overall Cd phytoremediation efficiency (p < 0.05). The amendment of organic manure promoted the biomass increase of B. vulgaris L. var. cicla (p < 0.05) but inhibited the Cd phytoremediation efficiency.


Asunto(s)
Beta vulgaris/metabolismo , Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Agricultura , Beta vulgaris/crecimiento & desarrollo , Biodegradación Ambiental , Cadmio/análisis , China , Monitoreo del Ambiente , Contaminantes del Suelo/análisis
8.
Phytopathology ; 101(9): 1052-60, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21834725

RESUMEN

Potato virus Y (PVY) strains were originally defined by interactions with different resistance genes in standard potato cultivars. Five distinct strain groups are defined that cause local or systemic hypersensitive responses (HRs) in genetic background with a corresponding N gene: PVY(O), PVY(N), PVY(C), PVY(Z), and PVY(E). The nucleotide sequences of multiple isolates of PVY(O) and PVY(N) differ from each other by ≈8% along their genomes. Additionally, complete genome sequences of multiple recombinant isolates are composed of segments of parental PVY(O) and PVY(N) sequences. Here, we report that recombinant isolate PVY-L26 induces an HR in potato 'Maris Bard' carrying the putative Nz gene, and is not recognized by two other resistance genes, Nc and Ny(tbr). These genetic responses in potato, combined with the inability of PVY-L26 to induce vein necrosis in tobacco, clearly define it as an isolate from the PVY(Z) strain group and provide the first information on genome structure and sequence of PVY(Z). The genome of PVY-L26 displays typical features of European NTN-type isolates with three recombinant junctions (PVY(EU-NTN)), and the PVY-L26 is named PVY(Z)-NTN. Three typical PVY(NTN) isolates and two PVY(N) isolates, all inducing vein necrosis in tobacco, were compared with PVY-L26. One PVY(NTN) isolate elicited HR reactions in Maris Bard, similar to PVY-L26, while two induced a severe systemic HR-like reaction quite different from the quasi-symptomless reaction induced by two PVY(N) isolates. 'Yukon Gold' potato from North America produced HR against several PVY(NTN) isolates, including PVY-L26, but only late and limited systemic necrosis against one PVY(N) isolate. Consequently, according to symptoms in potato indicators, both PVY(Z) and PVY(NTN) isolates appeared biologically very close and clearly distinct from PVY(O) and PVY(N) strain groups.


Asunto(s)
Genoma Viral/genética , Enfermedades de las Plantas/virología , Potyvirus/clasificación , Solanum tuberosum/virología , Tipificación Molecular , América del Norte , Fenotipo , Potyvirus/genética , Potyvirus/aislamiento & purificación , Recombinación Genética , Plantones/virología , Análisis de Secuencia de ADN , Nicotiana/virología
9.
Phytopathology ; 101(7): 778-85, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21675922

RESUMEN

The ordinary strain of Potato virus Y (PVY), PVY(O), causes mild mosaic in tobacco and induces necrosis and severe stunting in potato cultivars carrying the Ny gene. A novel substrain of PVY(O) was recently reported, PVY(O)-O5, which is spreading in the United States and is distinguished from other PVY(O) isolates serologically (i.e., reacting to the otherwise PVY(N)-specific monoclonal antibody 1F5). To characterize this new PVY(O)-O5 subgroup and address possible reasons for its continued spread, we conducted a molecular study of PVY(O) and PVY(O)-O5 isolates from a North American collection of PVY through whole-genome sequencing and phylogenetic analysis. In all, 44 PVY(O) isolates were sequenced, including 31 from the previously defined PVY(O)-O5 group, and subjected to whole-genome analysis. PVY(O)-O5 isolates formed a separate lineage within the PVY(O) genome cluster in the whole-genome phylogenetic tree and represented a novel evolutionary lineage of PVY from potato. On the other hand, the PVY(O) sequences separated into at least two distinct lineages on the whole-genome phylogenetic tree. To shed light on the origin of the three most common PVY recombinants, a more detailed phylogenetic analysis of a sequence fragment, nucleotides 2,406 to 5,821, that is present in all recombinant and nonrecombinant PVY(O) genomes was conducted. The analysis revealed that PVY(N:O) and PVY(N-Wi) recombinants acquired their PVY(O) segments from two separate PVY(O) lineages, whereas the PVY(NTN) recombinant acquired its PVY(O) segment from the same lineage as PVY(N:O). These data suggest that PVY(N:O) and PVY(N-Wi) recombinants originated from two separate recombination events involving two different PVY(O) parental genomes, whereas the PVY(NTN) recombinants likely originated from the PVY(N:O) genome via additional recombination events.


Asunto(s)
Variación Genética , Genoma Viral/genética , Enfermedades de las Plantas/virología , Potyvirus/clasificación , Potyvirus/genética , Solanum tuberosum/virología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Secuencia de Bases , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Chenopodium/virología , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/virología , Potyvirus/inmunología , Potyvirus/patogenicidad , ARN Viral/genética , Recombinación Genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Análisis de Secuencia de ADN , Serotipificación , Nicotiana/virología
10.
Virus Res ; 143(1): 68-76, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19463723

RESUMEN

A novel Potato virus Y (PVY) isolate, L26, recovered from a Frontier potato line was initially typed as a PVY(NTN) strain using multiplex RT-PCR and serological assays. However, L26 induced mosaic and mild vein clearing symptoms in tobacco rather than vein necrosis characteristic of the PVY (NTN) strain. The whole genome sequence was determined for L26 and two other PVY(NTN) isolates, HR1 and N4, from Idaho that did induce vein necrosis in tobacco. The sequence of all three isolates was similar to typical European PVY(NTN) isolates that contain three recombination junctions in their genome. The sequence of the L26 genome was nearly identical to the genomes HR1, N4, and to a previously characterized PVY(NTN) isolate, 423-3, differing by only five nucleotides in the entire ca. 9.7-kb genome, only one resulting in a corresponding amino acid change, D-205 to G-205 in the central region of HC-Pro. Two "signature" amino acid residues, thought involved in induction of the vein necrosis syndrome in tobacco, K-400 and E-419, were present in the C-terminal region of HC-Pro of all three isolates. Multiple alignment of the whole genome sequences of L26 and other PVY(NTN) isolates whose phenotype in tobacco has been reported, suggests that a single nucleotide change (A-1,627 to G-1,627) resulting in the single amino acid change (D-205 to G-205) in the HC-Pro cistron of L26 correlates with the loss of the vein necrosis phenotype in tobacco. Secondary structure modeling of the HC-Pro protein predicts the G-205 residue, and the previously identified residues K-400 and E-419, would all be located on the exposed surface of the protein. Taken together, these data suggest that the vein necrosis genetic determinant of PVY in tobacco is complex and includes other element(s), in addition to the C-terminal fragment of HC-Pro.


Asunto(s)
Necrosis/virología , Nicotiana/virología , Hojas de la Planta/citología , Potyvirus/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Cisteína Endopeptidasas/genética , ADN Recombinante/análisis , ADN Recombinante/genética , Genoma Viral , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/virología , Potyvirus/clasificación , Potyvirus/aislamiento & purificación , ARN Viral/análisis , ARN Viral/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Serotipificación , Solanum tuberosum/virología , Nicotiana/citología , Proteínas Virales/genética
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