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1.
Ticks Tick Borne Dis ; 12(3): 101679, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33578256

RESUMO

Ticks and tick-borne rickettsial diseases have been gaining greater attention in China over the past decade. However, most published studies to date have occurred in Northern China, with limited investigations occurring in China's southern provinces. As part of larger surveillance efforts, a cross-sectional survey was conducted in six sites at Guangdong, Guangxi and Yunnan investigating rickettsial infection in ticks. A total of 581 ticks were collected from hosts and screened via PCR, targeting rrs, gltA, ompB, sca4, and ompA gene fragments. Two of 12 Haemaphysalis formosensis ticks were infected with novel Rickettsia strain GD01, which was closest phylogenetically (97.3-98.9 % identity) to Rickettsia tamurae strain AT-1, but not within the same clade. Another detected strain (GD02) shared similar identity, 99-100 % across four gene targets, to recently detected Candidatus Rickettsia longicornii isolate ROK-HL727, with an overall prevalence of 12.5 % (71/569). The presence of such pathogens calls for increased public health attention and active surveillance in patients reporting recent tick bites.

2.
Vector Borne Zoonotic Dis ; 20(11): 817-824, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32749919

RESUMO

Background: Human babesiosis is an emerging zoonotic disease transmitted by ticks in China. A few systematic reports on Babesia spp. was involved with ticks, especially in the human babesiosis endemic areas in Northeastern China. Materials and Methods: Ticks were collected from 30 individual waypoints along 2.0 km transects in two recreational forests. Babesia spp. infection in ticks was screened by amplifying the partial 18s rRNA gene with subsequent sequencing. Multivariate logistic regression analysis was used to determine the association between tick infection and related environmental risk factors. Cluster analyses were performed using SaTScan v6.0 software to identify any geographical cluster of infected ticks. Results: A total of 2380 Ixodes persulcatus and 461 Haemaphysalis concinna ticks were collected. Of the 0.97% of I. persulcatus ticks that tested positive, five Babesia species were identified, including B. bigemina (n = 6), B. divergens (n = 2), B. microti (n = 3), B. venatorum (n = 11), and one novel strain HLJ-8. Thirteen (2.92%) H. concinna ticks tested positive for B. bigemina (n = 1), B. divergens (n = 1), three genetic variants of Babesia represented by HLJ-874, which was closely related to Babesia sp.MA#361-1, and eight other Babesia variants represented by HLJ242, which were similar to B. crassa. Each study site had 5-6 different Babesia spp. One waypoint was more likely to yield B. venatorum (relative risk = 15.36, p = 0.045) than all other waypoints. Conclusions: There exists a high genetic diversity of Babesia spp. across a relatively small sampled region. Further study is needed to understand the risks these variants pose to human health.

3.
Cell ; 182(5): 1328-1340.e13, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32814014

RESUMO

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.

4.
Vector Borne Zoonotic Dis ; 20(10): 755-762, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32679008

RESUMO

As one of the important tick-borne zoonotic pathogens, Anaplasma has both veterinary and public health significance. Here, we performed a survey of Anaplasma infection in the goats from a farm in Beijing, China, and found 44.6% (41/92) were infected with Anaplasma capra, and 22.8% (21/92) were infected with Anaplasma sp. This Anaplasma sp. bacterium was close to a recently emerging Anaplasma platys strain based on gltA and groEL gene phylogenetic analysis. As to further understand the characteristics of Anaplasma sp., we raised a couple of positive goats (n = 2) in the laboratory with tick-free settings. We observed inappetence, vomiting, high fever, and weakness of limbs in the goat's offspring (n = 3). In addition, the blood samples from all offspring were all positive of this Anaplasma spp. We did not see any intracellular morulae in neutrophils, monocytes, and erythrocytes, but we identified some in the platelets of the blood smears from the positive goats by light microscopy. We named it A. platys-like and suggested it may infect platelets and be transmitted vertically through the placenta of goats. These findings deserve further evaluation.

5.
Plant Physiol ; 183(1): 345-357, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179630

RESUMO

Hydrogen sulfide (H2S), a plant gasotransmitter, functions in the plant response to cadmium (Cd) stress, implying a role for cysteine desulfhydrase in producing H2S in this process. Whether d -CYSTEINE DESULFHYDRASE (DCD) acts in the plant Cd response remains to be identified, and if it does, how DCD is regulated in this process is also unknown. Here, we report that DCD-mediated H2S production enhances plant Cd tolerance in Arabidopsis (Arabidopsis thaliana). When subjected to Cd stress, a dcd mutant accumulated more Cd and reactive oxygen species and showed increased Cd sensitivity, whereas transgenic lines overexpressing DCD had decreased Cd and reactive oxygen species levels and were more tolerant to Cd stress compared with wild-type plants. Furthermore, the expression of DCD was stimulated by Cd stress, and this up-regulation was mediated by a Cd-induced transcription factor, WRKY13, which bound to the DCD promoter. Consistently, the higher Cd sensitivity of the wrky13-3 mutant was rescued by the overexpression of DCD Together, our results demonstrate that Cd-induced WRKY13 activates DCD expression to increase the production of H2S, leading to higher Cd tolerance in plants.

6.
Nature ; 583(7815): 282-285, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32218527

RESUMO

The ongoing outbreak of viral pneumonia in China and across the world is associated with a new coronavirus, SARS-CoV-21. This outbreak has been tentatively associated with a seafood market in Wuhan, China, where the sale of wild animals may be the source of zoonotic infection2. Although bats are probable reservoir hosts for SARS-CoV-2, the identity of any intermediate host that may have facilitated transfer to humans is unknown. Here we report the identification of SARS-CoV-2-related coronaviruses in Malayan pangolins (Manis javanica) seized in anti-smuggling operations in southern China. Metagenomic sequencing identified pangolin-associated coronaviruses that belong to two sub-lineages of SARS-CoV-2-related coronaviruses, including one that exhibits strong similarity in the receptor-binding domain to SARS-CoV-2. The discovery of multiple lineages of pangolin coronavirus and their similarity to SARS-CoV-2 suggests that pangolins should be considered as possible hosts in the emergence of new coronaviruses and should be removed from wet markets to prevent zoonotic transmission.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Eutérios/virologia , Evolução Molecular , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico , Sequência de Aminoácidos , Animais , Betacoronavirus/química , Betacoronavirus/classificação , China/epidemiologia , Quirópteros/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Reservatórios de Doenças/virologia , Genômica , Humanos , Malásia , Pandemias , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Recombinação Genética , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Zoonoses/virologia
7.
J Med Entomol ; 57(4): 1270-1276, 2020 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-32053722

RESUMO

The importance of ticks in veterinary and medical science has received much attention. The dominant tick species in northeastern China, Ixodes persulcatus tick can transmit various pathogens to humans and animals and there are some studies on the microbiome composition of this tick. Our study characterized the bacterial communities in I. persulcatus by 16S amplicon pyrosequencing and described the differences of microorganisms in male and female tick and assessed the variation of microorganisms in the development stages in northeastern China. We mainly found the following bacteria genera: Pseudomonas (Pseudomonadales: Pseudomonadaceae), Citrobacter (Enterobacteriales: Enterobacteriaceae), and Rickettsia (Rickettsiales: Rickettsiaceae). Rickettsia is common and harmful pathogen transmitted by ticks. Meanwhile, we found there were differences between male and female tick of microbiomes, and the diversity of microbiome increased from engorged female ticks to eggs, but decreased when the eggs were molting into larvae. Our data showed that male ticks exhibited greater microbial diversity than female I. persulcatus tick and larvae presented with a different bacterial community compared to engorged female tick and hatched eggs. These findings may be useful for further understanding the interaction between I. persulcatus and microbiome biology.

8.
Vector Borne Zoonotic Dis ; 20(2): 88-92, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31453762

RESUMO

Background: To date, there have been few investigations on Candidatus Rickettsia tarasevichiae in rodents carried out in China. In this study, we conducted surveillance for Candidatus R. tarasevichiae infection in rodents. A total of 463 rodents were captured at five survey sites in Mudanjiang, Heilongjiang province, where Candidatus R. tarasevichiae patients have been reported. PCR targeting citrate synthase and outer membrane protein genes was performed and positive amplicons were sequenced. Result: Candidatus R. tarasevichiae was detected in 1.29% of the 463 rodents sampled from the five survey sites in Mudanjiang, Heilongjiang province. Only 2 out of 13 (15.38%) Rattus norvegicus and 4 out of 80 (5%) Clethrionomys rufocanus collected from Dashigou forestry were positive for the gltA and ompA genes of Candidatus R. tarasevichiae DNA. The detected Candidatus R. tarasevichiae was in the same clade of sequences from patients in Mudanjiang based on phylogenetic analysis. Conclusion: Rodents are major host of ticks and also serve as reservoirs of spotted fever group (SFG) Rickettsia. Although this is the first confirmation of Candidatus R. tarasevichiae detected in rodents in China, further investigations are needed to clarify the distribution of Candidatus R. tarasevichiae in rodents elsewhere and what role they play as reservoirs.

9.
New Phytol ; 225(1): 297-309, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31403703

RESUMO

Lateral roots (LRs), which form in the plant postembryonically, determine the architecture of the root system. While negative regulatory factors that inhibit LR formation and are counteracted by auxin exist in the pericycle, these factors have not been characterised. Here, we report that SHI-RELATED SEQUENCE5 (SRS5) is an intrinsic negative regulator of LR formation and that auxin signalling abolishes this inhibitory effect of SRS5. Whereas LR primordia (LRPs) and LRs were fewer and less dense in SRS5ox and Pro35S:SRS5-GFP plants than in the wild-type, they were more abundant and denser in the srs5-2 loss-of-function mutant. SRS5 inhibited LR formation by directly downregulating the expression of LATERAL ORGAN BOUNDARIES-DOMAIN 16 (LBD16) and LBD29. Auxin repressed SRS5 expression. Auxin-mediated repression of SRS5 expression was not observed in the arf7-1 arf19-1 double mutant, likely because ARF7 and ARF19 bind to the promoter of SRS5 and inhibit its expression in response to auxin. Taken together, our data reveal that SRS5 negatively regulates LR formation by repressing the expression of LBD16 and LBD29 and that auxin releases this inhibitory effect through ARF7 and ARF19.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Ácidos Indolacéticos/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Estradiol/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Modelos Biológicos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Regiões Promotoras Genéticas/genética , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento
10.
EBioMedicine ; 43: 317-324, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31003930

RESUMO

BACKGROUND: A tick-borne segmented RNA virus called Jingmen tick virus (JMTV) was recently identified, variants of which were detected in a non-human primate host and fatal patients with Crimean-Congo haemorrhagic fever. We investigated its infectivity and pathogenicity for humans. METHODS: We obtained skin-biopsy, blood and serum samples from patients with tick bites, and used high-throughput sequencing, in situ hybridisation, and serologic testing to diagnose and ascertain the cases of JMTV infection. FINDINGS: A JMTV strain was isolated from the tick Amblyomma javanense into an embryo-derived tick cell line. We obtained sustained passage of JMTV, and revealed that it was able to accumulate in salivary glands of experimentally infected ticks. Four JMTV-infected patients were identified by high-throughput sequencing of skin biopsies and blood samples. The virus replication in skin tissue was visualised by in situ hybridisation. The four patients all had an itchy or painful eschar at the site of tick bite, with or without lymphadenopathy. Immunohistochemical examination revealed remarkable local inflammation manifested as infiltration by neutrophils. Eight patients were identified by serological testing and showed more severe clinical manifestations. Two Ixodes persulcatus ticks detached from patients were positive for JMTV. All JMTV strains identified in this study formed a well-supported sub-lineage, distinct from those previously reported in China. Interpretation The public significance of JMTV should be highly concerning due to its potential pathogenicity for humans and efficient transmission by potential ticks. FUND: China Natural Science Foundation, State Key Research Development Programme, and United Kingdom Biotechnology and Biological Sciences Research Council.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/virologia , Flavivirus , Biomarcadores , China , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/transmissão , Flavivirus/classificação , Flavivirus/genética , Infecções por Flavivirus/diagnóstico , Infecções por Flavivirus/transmissão , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Hibridização In Situ , Filogenia , Vigilância em Saúde Pública , RNA Viral , Estudos Retrospectivos , Testes Sorológicos , Pele/patologia , Picadas de Carrapatos
11.
Front Plant Sci ; 9: 1634, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30542353

RESUMO

Nitric oxide (NO) production via NO synthase (NOS) plays a vital role in plant tolerance to salt stress. However, the factor(s) regulating NOS-like activity in plant salt stress tolerance remains elusive. Here, we show that Arabidopsis SORTING NEXIN 1 (SNX1), which can restore H2O2-induced NO accumulation in yeast Δsnx4 mutant, functions in plant salt stress tolerance. Salt stress induced NO accumulation through promoted NOS-like activity in the wild type, but this induction was repressed in salt-stressed snx1-2 mutant with the mutation of SNX1 because NOS-like activity was inhibited in the mutant. Consistently, snx1-2 displayed reduced tolerance to high salinity with decreased survival rate compared with the wild type, and exogenous treatment with NO donor significantly rescued the hypersensitivity of the mutant to salt stress. In addition, the snx1-2 mutant with reduced NOS-like activity repressed the expression of stress-responsive genes, decreased proline accumulation and anti-oxidant ability compared with wild-type plants when subjected to salt stress. Taken together with our finding that salt induces the expression of SNX1, our results reveal that SNX1 plays a crucial role in plant salt stress tolerance by regulating NOS-like activity and thus NO accumulation.

12.
Plant Cell ; 30(10): 2368-2382, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30150309

RESUMO

Plant seedlings undergo distinct developmental processes in the dark and in the light. Several genes, including ELONGATED HYPOCOTYL5 (HY5), B-BOX PROTEIN21 (BBX21), and BBX22, have been identified as photomorphogenesis-promoting factors in Arabidopsis thaliana; however, the overexpression of these genes does not induce photomorphogenesis in the dark. Using an activation-tagging approach, we identified SRS5ox, which overexpresses SHI-RELATED SEQUENCE5 (SRS5) following induction with estradiol. SRS5 overexpression in SRS5ox and Pro35S:SRS5-GFP seedlings results in a constitutive photomorphogenesis phenotype in the dark, whereas SRS5 loss of function in the srs5-2 mutant results in long hypocotyls in the light. This indicates that SRS5 is a positive regulator of photomorphogenesis. Furthermore, SRS5 promotes photomorphogenesis by directly binding to the promoters of photomorphogenesis-promoting genes, such as HY5, BBX21, and BBX22, and activating their expression, thus affecting the expression of downstream light-signaling genes. These data indicate that SRS5 acts in the upregulation of photomorphogenesis-promoting genes. In addition, CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), which plays a central repressive role in seedling photomorphogenesis, directly ubiquitinates SRS5, promoting its degradation in the dark. Taken together, our results demonstrate that SRS5 directly activates the expression of downstream genes HY5, BBX21, and BBX22 and is a target of COP1-mediated degradation in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hipocótilo/genética , Hipocótilo/crescimento & desenvolvimento , Proteínas Nucleares/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Plântula/genética , Plântula/fisiologia , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(3): 777-780, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28641634

RESUMO

OBJECTIVE: To explore the value of bone marrow smear combined with biopsy in the diagnosis of lymphoma. METHODS: Clinical data of 50 cases of lymphoma from our hospital were analyzed retrospectively, and the results of the bone marrow smear and the bone marrow biopsy were compared simultaneously. RESULTS: The decision for the degree of bone marrow hyperplasia in bone marrow biopsy slice was superior to that in smear, and the active or highly active hyperplasia of nucleated cells were observed in all the bone marrow biopsies; the lymphomatic cells were observed in bone marrow smear of the 12 patients(24%), but the bone marrow biopsies showed a higher detection rate of lymphomatic cells 44% in 22 patients(P<0.05); The hyperplasia of bone marrow fibrous tissue, mainly mild to moderate, were the common in cases with bone marrow involvement and the severity of bone marrow fibrosis positively correlated with the number of lymphomatic cells. CONCLUSION: Biopsy combined with aspiration can improve the accuracy of diagnosis in lymphoma with bone marrow involvement.


Assuntos
Linfoma/diagnóstico , Biópsia , Medula Óssea , Doenças da Medula Óssea , Exame de Medula Óssea , Humanos
14.
Ann Hematol ; 96(7): 1085-1095, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28421266

RESUMO

The adverse effects of iron overload have raised more concerns as a growing number of studies reported its association with immune disorders. This study aimed to investigate alterations in the immune system by iron overload in patients with myelodysplastic syndrome (MDS) and an iron-overloaded mouse model. The peripheral blood from patients was harvested to test the effect of iron overload on the subsets of T lymphocytes, and the level of reactive oxygen species (ROS) was also evaluated. The data showed that iron-overloaded patients had a lower percentage of CD3+ T cells and disrupted T cell subsets, concomitant with higher ROS level in lymphocytes. In order to explore the mechanism, male C57Bl/6 mice were intraperitoneally injected with iron dextran at a dose of 250 mg/kg every 3 days for 4 weeks to establish an iron-overloaded mouse model and the blood of each mouse was collected for the analysis of the T lymphocyte subsets and T cell apoptosis. The results showed that iron overload could reduce the percentage of CD3+ T cells and the ratio of Th1/Th2 and Tc1/Tc2 but increase the percentage of regulatory T (Treg) cells and the ratio of CD4/CD8. We also found that iron overload induced the apoptosis of T lymphocytes and increased its ROS level. Furthermore, these effects could be partially recovered after treating with antioxidant N-acetyl-L-cysteine (NAC) or iron chelator deferasirox (DFX). Taken together, these observations indicated that iron overload could selectively affect peripheral T lymphocytes and induce an impaired cellular immunity by increasing ROS level.


Assuntos
Sobrecarga de Ferro/metabolismo , Síndromes Mielodisplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Subpopulações de Linfócitos T/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Complexo CD3/sangue , Relação CD4-CD8 , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Sobrecarga de Ferro/sangue , Contagem de Linfócitos , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Células Th1/metabolismo , Células Th2/metabolismo
15.
Plant Sci ; 252: 282-289, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27717464

RESUMO

As sessile organisms, plants require many flexible strategies to adapt to the environment. Although some environmental signaling pathways regulating stomatal development have been identified, how stomatal regulators are modulated by internal and external signals to determine the final stomatal abundance requires further exploration. In our studies, we found that nitric oxide (NO) promotes stomatal development with increased stomatal index as well as the relative number of meristemoids and guard mother cells [%(M+GMC)] in NO-treated wild-type Arabidopsis plants; this role of NO was further verified in the nox1 mutant, which exhibits higher NO levels, and the noa1 mutant, which exhibits low NO accumulation. To gain insight into the molecular mechanisms underlying the effect of NO, we further assayed the expression of genes involved in stomatal development and found that NO induces the expression of the master regulators SPCH, MUTE and SCRM2 to initiate stomatal development. In addition, MPK6 is also involved in NO-promoted stomatal development, as MPK6 expression was repressed in nox1 and NO-treated plants, and transgenic plants overexpressing MPK6 were less sensitive to SNP treatment in terms of changes in the%(M+GMC). Thus, our study shows that NO promotes the production of stomata by up-regulating the expression of SPCH, MUTE and SCRM2 and down-regulating MPK6 expression.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Estômatos de Plantas/crescimento & desenvolvimento , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/farmacologia , Óxido Nítrico/fisiologia , Estômatos de Plantas/genética , Estômatos de Plantas/metabolismo , Transdução de Sinais
16.
Plant Physiol Biochem ; 109: 240-247, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27750098

RESUMO

Protein kinase CK2, which consists of two α and two ß subunits, plays an essential role in plant development and is implicated in plant responses to abiotic stresses, including salt and heat. However, the function of CK2 in response to heavy metals such as cadmium (Cd) has not yet been established. In this study, the transgenic line CKB4ox, which overexpresses CKB4 encoding the CK2ß subunit and has elevated CK2 activity, was used to investigate the potential role of CK2 in response to Cd stress in Arabidopsis thaliana. Under Cd stress, CKB4ox showed reduced root growth and biomass accumulation as well as decreased chlorophyll and proline contents compared with wild type. Furthermore, increased Cd accumulation and a higher H2O2 content were found in CKB4ox, possibly contributing to the inhibition of CKB4ox growth under Cd stress. Additionally, altered levels of Cd and H2O2 were found to be associated with decreased expression of genes involved in Cd efflux, Cd sequestration and H2O2 scavenging. Taken together, these results suggest that elevated expression of CKB4 and increased CK2 activity enhance the sensitivity of plants to Cd stress by affecting Cd and H2O2 accumulation, including the modulation of genes involved in Cd transport and H2O2 scavenging. This study provides direct evidence for the involvement of plant CK2 in the response to Cd stress.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cádmio/farmacocinética , Cádmio/toxicidade , Caseína Quinase II/metabolismo , Peróxido de Hidrogênio/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Transporte Biológico Ativo/genética , Caseína Quinase II/genética , Clorofila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Plantas Geneticamente Modificadas , Prolina/metabolismo , Subunidades Proteicas , Estresse Fisiológico
17.
Fitoterapia ; 101: 64-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25549926

RESUMO

Curculigoside has an extensive pharmacological activity, including estrogen-like, improving sexual behavior, antiosteoporotic, antioxidant, immunomodulatory and neuroprotective effects. However, few investigations have been conducted about the pharmacokinetics and tissue distribution of curculigoside to better understand its behavior and action mechanism in vivo. Thus, a sensitive and reliable liquid chromatography with mass spectrometry (HPLC-MS) method was established and validated for the quantification of curculigoside in rat plasma and tissue samples. Biological samples were processed with methanol precipitation, and naringin was used as the internal standard. Chromatographic separation was performed on an Agilent XDB-C18 chromatography column (3.0mm×50mm, 1.8µm) with a mobile phase consisting of acetonitrile and 0.1% formic acid. Quantification was performed by selected ion monitoring with m/z 511.1 [M+HCO2](-) for curculigoside and m/z 579.1 [M-H](-) for the internal standard. The validated method was successfully applied to the pharmacokinetic and tissue distribution study of curculigoside in rats. Non-compartmental pharmacokinetic parameters indicated that curculigoside had rapid distribution, extensive tissue uptake, and poor absorption into systemic circulation. The values of absolute bioavailability were 0.38%, 0.22% and 0.27% for oral doses of 100, 200 and 400mg/kg, respectively. The results of the tissue distribution study suggested that curculigoside was distributed into the heart, lung, spleen, intestine, stomach, kidney, thymus, liver, brain, testis, and bone marrow after oral administration of 150mg/kg. In conclusion, the present study may provide a material basis for study of the pharmacological action of curculigoside, and meaningful insights into further study on clinical application.


Assuntos
Benzoatos/farmacocinética , Glucosídeos/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Cromatografia Líquida , Feminino , Injeções Intravenosas , Masculino , Espectrometria de Massas , Estrutura Molecular , Ratos Sprague-Dawley , Distribuição Tecidual
18.
Complement Ther Med ; 22(4): 724-30, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25146078

RESUMO

Complementary therapies such as acupuncture are suggested to have enhanced placebo effects. Numerous high quality randomized controlled trials found that acupuncture is no better than its placebo control; however, patients in both real and sham acupuncture groups report clinically meaningful symptom improvements. A possible interpretation of these trials is that acupuncture acts entirely by engaging placebo mechanisms. This article provides further evidence supporting that acupuncture might be a potent placebo, and explains how to address major concerns following this suggestion.


Assuntos
Terapia por Acupuntura , Efeito Placebo , Ensaios Clínicos como Assunto/ética , Ensaios Clínicos como Assunto/psicologia , Humanos
20.
PLoS One ; 9(1): e85720, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465665

RESUMO

Plants can be adapted to the changing environments through tropic responses, such as light and gravity. One of them is root negative phototropism, which is needed for root growth and nutrient absorption. Here, we show that the auxin efflux carrier PIN-FORMED (PIN) 1 is involved in asymmetric auxin distribution and root negative phototropism. In darkness, PIN1 is internalized and localized to intracellular compartments; upon blue light illumination, PIN1 relocalize to basal plasma membrane in root stele cells. The shift of PIN1 localization induced by blue light is involved in asymmetric auxin distribution and root negative phototropic response. Both blue-light-induced PIN1 redistribution and root negative phototropism is mediated by a BFA-sensitive trafficking pathway and the activity of PID/PP2A. Our results demonstrate that blue-light-induced PIN1 redistribution participate in asymmetric auxin distribution and root negative phototropism.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/genética , Fototropismo/genética , Raízes de Plantas/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Escuridão , Ácidos Indolacéticos/metabolismo , Luz , Proteínas de Membrana Transportadoras/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/metabolismo , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Transporte Proteico/efeitos da radiação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
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