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1.
Medicine (Baltimore) ; 103(36): e39617, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39252220

RESUMO

There are high rates of human immunodeficiency virus (HIV) and Treponema pallidum coinfection, HIV can increase the incidence and disability rate of neurosyphilis. However, there is a lack of data about the risk factors associated with the development of symptomatic neurosyphilis (SNS). We retrospectively reviewed the medical records of inpatients with concurrent syphilis and HIV infection who underwent a lumbar puncture and completed cerebrospinal fluid (CSF) examination. Sixty inpatients were consecutively enrolled from Beijing Ditan Hospital between January 2015 and March 2023. The clinical and laboratory features were evaluated between the SNS and asymptomatic neurosyphilis (ANS) groups. All patients were male, 25% (15/60) patients were diagnosed with ANS, and 75% (45/60) patients were diagnosed with SNS. Meningovascular neurosyphilis was the most prevalent clinical form in this study. Age, CD4 cell count, highly active antiretroviral therapy use, and serum HIV viral load showed no statistically significant differences between the 2 groups. The SNS group lacked early detection of syphilis (P < .001) and did not get previous adequate therapy for syphilis (P < .001) than the ANS group, as well as a higher initial serum toluidine red unheated serum test (TRUST) titer, current serum TRUST titer, CSF white blood cell count (WBC), protein concentration, and CSF TRUST titer (P = .014, P = .042, P = .01, P = .007, and P = .007, respectively). In multivariable logistic regression, high CSF WBC count (odds ratio = 1.08; P = .032) and previous treatment of syphilis (odds ratio = 0.01; P = .049) related to the SNS. Lack of antisyphilis treatment in the early stage of syphilis and a higher CSF WBC count are related risk factors for SNS in HIV-infected patients. Meningovascular neurosyphilis should get more attention in young patients with cryptogenic stroke.


Assuntos
Infecções por HIV , Neurossífilis , Humanos , Masculino , Neurossífilis/diagnóstico , Neurossífilis/líquido cefalorraquidiano , Neurossífilis/complicações , Neurossífilis/epidemiologia , Estudos Retrospectivos , Infecções por HIV/complicações , Adulto , China/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Coinfecção , Contagem de Linfócito CD4
2.
China CDC Wkly ; 5(8): 180-183, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-37008671

RESUMO

Introduction: In November 2021, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant was identified as the variant of concern and has since spread globally, replacing other cocirculating variants. To better understand the dynamic changes in viral load over time and the natural history of the virus infection, we analyzed the expression of the open reading frames 1ab (ORF1ab) and nucleocapsid (N) genes in patients infected with Omicron. Methods: We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25, 2022. We collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial kits. We depicted the cycle threshold (Ct) values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time series. Results: A total of 480 inpatients were included in the study, with a median age of 59 years (interquartile range, 42 to 78; range, 16 to 106). In the <45-year-old age group, the Ct values for ORF1ab and N gene amplification remained below 35 for 9.0 and 11.5 days, respectively. In the ≥80-year-old age group, the Ct values for ORF1ab and N genes stayed below 35 for 11.5 and 15.0 days, respectively, which was the longest among all age groups. The Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene amplification. Conclusion: The time to test negative varied among different age groups, with viral nucleic acid shedding taking longer in older age groups compared to younger age groups. As a result, the time to resolution of Omicron infection increased with increasing age.

3.
Front Plant Sci ; 14: 1118777, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875573

RESUMO

Introduction: Pre-harvest Sprouting (PHS) seriously affects wheat quality and yield. However, to date there have been limited reports. It is of great urgency to breed resistance varieties via quantitative trait nucleotides (QTNs) or genes for PHS resistance in white-grained wheat. Methods: 629 Chinese wheat varieties, including 373 local wheat varieties from 70 years ago and 256 improved wheat varieties were phenotyped for spike sprouting (SS) in two environments and genotyped by wheat 660K microarray. These phenotypes were used to associate with 314,548 SNP markers for identifying QTNs for PHS resistance using several multi-locus genome-wide association study (GWAS) methods. Their candidate genes were verified by RNA-seq, and the validated candidate genes were further exploited in wheat breeding. Results: As a result, variation coefficients of 50% and 47% for PHS in 629 wheat varieties, respectively, in 2020-2021 and 2021-2022 indicated large phenotypic variation, in particular, 38 white grain varieties appeared at least medium resistance, such as Baipimai, Fengchan 3, and Jimai 20. In GWAS, 22 significant QTNs, with the sizes of 0.06% ~ 38.11%, for PHS resistance were stably identified by multiple multi-locus methods in two environments, e.g., AX-95124645 (chr3D:571.35Mb), with the sizes of 36.390% and 45.850% in 2020-2021 and 2021-2022, respectively, was detected by several multi-locus methods in two environments. As compared with previous studies, the AX-95124645 was used to develop Kompetitive Allele-Specific PCR marker QSS.TAF9-3D (chr3D:569.17Mb~573.55Mb) for the first time, especially, it is available in white-grain wheat varieties. Around this locus, nine genes were significantly differentially expressed, and two of them (TraesCS3D01G466100 and TraesCS3D01G468500) were found by GO annotation to be related to PHS resistance and determined as candidate genes. Discussion: The QTN and two new candidate genes related to PHS resistance were identified in this study. The QTN can be used to effectively identify the PHS resistance materials, especially, all the white-grained varieties with QSS.TAF9-3D-TT haplotype are resistant to spike sprouting. Thus, this study provides candidate genes, materials, and methodological basis for breeding wheat PHS resistance in the future.

4.
Sci Rep ; 12(1): 743, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35031639

RESUMO

Examining continuous seismic data recorded by a dense broadband seismic network throughout Taipei shows for the first time, the nature of seismic noise in this highly populated metropolitan area. Using 140 broadband stations in a 50 km × 69 km area, three different recurring, strong noise signals characterized by dominant frequencies of 2-20 Hz, 0.25-1 Hz, and < 0.2 Hz are explored. At frequencies of 2-20 Hz, the seismic noise exhibits daily and weekly variations, and a quiescence during the Chinese New Year holidays. The largest amplitude occurred at a station located only 400 m from a traffic-roundabout, one of the busiest intersections in Taipei, suggesting a possible correlation between large amplitude and traffic flow. The median daily amplitude for the < 0.2 Hz and 0.2-1.0 Hz frequency bands is mostly synchronized with high similarity between stations, indicating that the sources are persistent oceanic or atmospheric perturbations across a large area. The daily amplitude for the > 2 Hz band, however, is low, indicating a local source that changes on shorter length scales. Human activities responsible for the 2-40 Hz energy in the city, we discovered, are able to produce amplitudes approximately 2 to 1500 times larger than natural sources. Using the building array deployed in TAIPEI 101, the tallest building in Taiwan, we found the small but repetitive ground vibration induced by traffic has considerable effect on the vibration behavior of the high-rise building. This finding urges further investigation not only on the dynamic and continuous interaction between vehicles, roads, and buildings, but also the role of soft sediment on such interaction.

5.
Plant Sci ; 303: 110772, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33487356

RESUMO

L-amino acid oxidase (ThLAAO) secreted by Trichoderma harzianum ETS323 is a flavoenzyme with antimicrobial characteristics. In this study, we transformed the ThLAAO gene into tobacco to elucidate whether ThLAAO can activate defense mechanisms and confer resistance against phytopathogens. Transgenic tobacco overexpressing ThLAAO showed enhanced resistance against Sclerotinia sclerotiorum and Botrytis cinerea and activated the expression of defense-related genes and the genes involved in salicylic acid, jasmonic acid, and ethylene biosynthesis accompanied by substantial accumulation of H2O2 in chloroplasts, cytosol around chloroplasts, and cell membranes of transgenic tobacco. Scavenge of H2O2 with ascorbic acid abolished disease resistance against B. cinerea infection and decreased the expression of defense-related genes. ThLAAO-FITC application on tobacco protoplast or overexpression of ThLAAO-GFP in tobacco revealed the localization of ThLAAO in chloroplasts. Chlorophyll a/b binding protein (CAB) was isolated through ThLAAO-ConA affinity chromatography. The pull down assay results confirmed ThLAAO-CAB binding. Application of ThLAAO-Cy5.5 on cabbage roots promptly translocated to the leaves. Treatment of ThLAAO on cabbage roots induces systemic resistance against B. cinerea. Overall, these results demonstrate that ThLAAO may target chloroplast and activate defense mechanisms via H2O2 signaling to confer resistance against S. sclerotiorum and B. cinerea.


Assuntos
Ascomicetos , Botrytis , Resistência à Doença/genética , Proteínas Fúngicas/genética , Hypocreales/genética , L-Aminoácido Oxidase/genética , Nicotiana/imunologia , Doenças das Plantas/imunologia , Proteínas Fúngicas/fisiologia , Peróxido de Hidrogênio/metabolismo , Hypocreales/enzimologia , L-Aminoácido Oxidase/fisiologia , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Nicotiana/genética , Nicotiana/microbiologia
6.
Arch Microbiol ; 203(4): 1641-1647, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33432379

RESUMO

To investigate the molecular mechanism of Trichoderma L-amino acid oxidase (Th-LAAO) in protecting and in promoting growth of cabbage infected with Botrytis cinerea, a three-way interaction system was established. Cabbage leaves treated with purified Th-LAAO significantly constrained damaged leaf area caused by B. cinerea infection. In response to Th-LAAO treatment, the expression levels of genes involved in photosynthesis, such as ribulose-1,5-bisphosphate carboxylase oxygenase, Rubisco activase, and ATP synthase increased 2.54, 2.18, and 1.41 folds, respectively. The transcription levels of sucrose transport protein 1 increased 7.6 fold. As to the expression of defense-related genes, the transcription level of ascorbate peroxidase increased 1.46 fold. On the contrary, pathogenesis-related protein 1, chitinase, ß-1,3 glucanase, and glutathione S-transferase decreased significantly. Overall, the results indicated that Th-LAAO may stimulate CO2 fixation and sucrose transport and elicit host defense responses in cabbage against B. cinerea, and this elicitation of defense response is likely to contribute to induced systemic resistance of host plant.


Assuntos
Brassica , Resistência à Doença , L-Aminoácido Oxidase , Trichoderma , Botrytis/fisiologia , Brassica/efeitos dos fármacos , Brassica/genética , Brassica/microbiologia , Resistência à Doença/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , L-Aminoácido Oxidase/isolamento & purificação , L-Aminoácido Oxidase/farmacologia , Fotossíntese/efeitos dos fármacos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Trichoderma/química , Trichoderma/enzimologia
7.
Biomed Res Int ; 2019: 2426313, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198783

RESUMO

A retrospective study was performed to compare the differences in clinical and laboratory features of asymptomatic neurosyphilis (ANS) and symptomatic neurosyphilis (SNS). A total of 264 HIV-negative inpatients with neurosyphilis were enrolled from Beijing Ditan Hospital and Beijing Tiantan Hospital between January 2014 and May 2018, including 110 SNS and 154 ANS. The SNS group had more patients in males, older median age and without antisyphilis treatment than ANS group (P<0.001, P<0.001, and P<0.001, respectively). The laboratory findings showed that the SNS group had higher pretreatment serum rapid plasma regain (RPR) titer, current serum RPR titer, cerebrospinal fluid (CSF) white blood cell (WBC) counts, CSF protein concentrations, and higher positive CSF RPR rate than those in the ANS group (P=0.011, P<0.001, P<0.001, P<0.001, and P<0.001, respectively). The multivariate logistic regression analysis revealed that male (OR=2.833, P=0.009), age≥45 years (OR=3.611, P=0.001), without antisyphilis treatment (OR=0.247, P<0.001), higher current serum RPR titer (OR=1.373, P=0.022), positive CSF RPR (OR=4.616, P<0.001), and higher CSF protein concentration (OR=1.017, P=0.026) were independent risk predictors for SNS. Therefore, clinical and laboratory features between SNS and ANS are quietly different. Male gender, age≥45 years, and lack of antisyphilis treatment are risk factors for SNS. The elevated level of serum RPR titer, CSF protein concentration, and CSF RPR titer may indicate the development of neurosyphilis and the aggravation of neurological symptoms.


Assuntos
Neurossífilis , Adulto , Fatores Etários , Feminino , Infecções por HIV , HIV-1 , Humanos , Masculino , Pessoa de Meia-Idade , Neurossífilis/sangue , Neurossífilis/líquido cefalorraquidiano , Neurossífilis/diagnóstico , Neurossífilis/patologia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
8.
Mol Plant Microbe Interact ; 31(7): 683-691, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29436965

RESUMO

A new clade, Trichoderma formosa, secretes eliciting plant response-like 1 (Epl1), a small peptide elicitor that stimulates plant immunity. Nicotiana benthamiana pretreated with Epl1 for 3 days developed immunity against Tomato mosaic virus (ToMV) infection. The transcriptome profiles of T. formosa and N. benthamiana were obtained by deep sequencing; the transcript of Epl1 is 736 nt in length and encodes a 12-kDa peptide. Identifying critical genes in Epl1-mediated immunity was challenging due to high similarity between the transcriptome expression profiles of Epl1-treated and ToMV-infected N. benthamiana samples. Therefore, an efficient bioinformatics data mining approach was used for high-throughput transcriptomic assays in this study. We integrated gene-to-gene network analysis into the ContigViews transcriptome database, and genes related to jasmonic acid and ethylene signaling, salicylic acid signaling, leucine-rich repeats, transcription factors, and histone variants were hubs in the gene-to-gene networks. In this study, the Epl1 of T. formosa triggers plant immunity against various pathogen infections. Moreover, we demonstrated that high-throughput data mining and gene-to-gene network analysis can be used to identify critical candidate genes for further studies on the mechanisms of plant immunity.


Assuntos
Proteínas Fúngicas/farmacologia , Redes Reguladoras de Genes , Nicotiana/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Trichoderma/imunologia , Sequência de Bases , DNA Fúngico , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Regulação da Expressão Gênica de Plantas/imunologia , Imunidade Inata , Modelos Moleculares , Filogenia , Proteínas de Plantas/genética , Conformação Proteica , Nicotiana/genética , Nicotiana/imunologia , Trichoderma/genética
9.
J Agric Food Chem ; 65(48): 10489-10494, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29111710

RESUMO

To document the safety of pachybasin, a secondary metabolite of Trichoderma harzianum, for use as a bioagricultural agent, it was subjected to general toxicological testing in mice and developmental toxicity in zebrafish. With either 5 or 20 mg kg-1 pachybasin i.p. injection, mice behavioral responses such as motor coordination, spontaneous locomotor activity, or nociceptive pain were not influenced. In long-term effect (daily injection for 14 days), the physiological, hematological, liver, and kidney functions were not altered either. Evidence for the developmental toxicity of pachybasin (10-100 µM) in 72-h exposure period was shown in zebrafish larvae, based on developmental retardation, impairment of chorion, and increase of mortality. In summary, there are no significant general toxicities presented in the pachybasin-treated adult male mice. However, the embryo-toxicity in aquatic biota should be taken into consideration during bioagricultural agent application.


Assuntos
Antraquinonas/toxicidade , Fungicidas Industriais/toxicidade , Camundongos/crescimento & desenvolvimento , Trichoderma/química , Peixe-Zebra/crescimento & desenvolvimento , Animais , Antraquinonas/química , Antraquinonas/metabolismo , Fungicidas Industriais/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Atividade Motora/efeitos dos fármacos , Metabolismo Secundário , Trichoderma/metabolismo
10.
PLoS One ; 12(4): e0174530, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28380050

RESUMO

OBJECTIVE: To investigate the awareness and use of the Systematic Review Center for Laboratory Animal Experimentation's (SYRCLE) risk-of-bias tool, the Animal Research: Reporting of In Vivo Experiments (ARRIVE) reporting guidelines, and Gold Standard Publication Checklist (GSPC) in China in basic medical researchers of animal experimental studies. METHODS: A national questionnaire-based survey targeting basic medical researchers was carried in China to investigate the basic information and awareness of SYRCLE's risk of bias tool, ARRIVE guidelines, GSPC, and animal experimental bias risk control factors. The EpiData3.1 software was used for data entry, and Microsoft Excel 2013 was used for statistical analysis in this study. The number of cases (n) and percentage (%) of classified information were statistically described, and the comparison between groups (i.e., current students vs. research staff) was performed using chi-square test. RESULTS: A total of 298 questionnaires were distributed, and 272 responses were received, which included 266 valid questionnaires (from 118 current students and 148 research staff). Among the 266 survey participants, only 15.8% was aware of the SYRCLE's risk of bias tool, with significant difference between the two groups (P = 0.003), and the awareness rates of ARRIVE guidelines and GSPC were only 9.4% and 9.0%, respectively; 58.6% survey participants believed that the reports of animal experimental studies in Chinese literature were inadequate, with significant difference between the two groups (P = 0.004). In addition, only approximately 1/3 of the survey participants had read systematic reviews and meta-analysis reports of animal experimental studies; only 16/266 (6.0%) had carried out/participated in and 11/266 (4.1%) had published systematic reviews/meta-analysis of animal experimental studies. CONCLUSIONS: The awareness and use rates of SYRCLE's risk-of-bias tool, the ARRIVE guidelines, and the GSPC were low among Chinese basic medical researchers. Therefore, specific measures are necessary to promote and popularize these standards and specifications and to introduce these standards into guidelines of Chinese domestic journals as soon as possible to raise awareness and increase use rates of researchers and journal editors, thereby improving the quality of animal experimental methods and reports.


Assuntos
Experimentação Animal/normas , Publicações/normas , Pesquisadores/estatística & dados numéricos , Animais , Viés , China , Humanos , Pesquisadores/psicologia , Fatores de Risco
11.
BMC Neurol ; 17(1): 1, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28056870

RESUMO

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a clinically heterogeneous disorder characterized by epileptic seizures, psychosis, dyskinesia, consciousness impairments, and autonomic instability. Symptoms are always various. Sometimes it presents in milder or incomplete forms. We report 4 cases of anti-NMDAR encephalitis with incomplete forms, 3 cases of which were accompanied by neuromyelitis optica spectrum disorder or neurosyphilis respectively. CASE PRESENTATION: A 33-year-old man presented with dysarthria, movement disorder and occasional seizures. He had 6 relapses in 28 years. When suffered from upper respiratory tract syndrome, he developed behavioral and consciousness impairment. Cranial MRI was normal. Viral PCR studies and oncologic work-up were negative. Anti-NMDAR antibody was detected in CSF and serum. A 21-year-old female manifested dizziness and diplopia ten months and six months before, respectively. Both responded to steroid therapy and improved completely. This time she presented with progressive left limb and facial anesthesia, walking and holding unsteadily. Spinal cord MRI follow-up showed abnormality of medulla oblongata and cervical cord(C1). Anti-AQP4 and anti-NMDAR were positive in CSF. Steroid-pulse therapy ameliorated her symptoms. A 37-year-old male experienced worsening vision. He was confirmed neurosyphilis since the CSF tests for syphilis were positive. Protein was elevated and the oligoclonal IgG bands(OB) and anti-NMDAR was positive in CSF. Anti-aquaporin 4(AQP4) antibodies and NMO-IgG were negative. Cranial MRI showed high FLAIR signal on frontal lobe and low T2 signal adjacent to the right cornu posterious ventriculi lateralis. Treatment for neurosyphlis was commenced with gradual improvement. A 39-year-old male, developed serious behavioral and psychiatric symptoms. Examination showed abnormal pupils and unsteady gait. He was confirmed neurosyphilis according to the CSF tests for syphilis. Anti-NMDAR was positive in CSF and serum. Cranial MRI showed lateral ventricles and the third ventricle enlargement and signal abnormality involving bilateral temporal lobe, corona radiate and centrum semiovale. PenicillinG, pulsed methylprednisolone and intravenous immunoglobulin was administered. He was stable. CONCLUSION: Anti-NMDAR encephalitis can present in atypical types. When relapsing, it may present with partial aspects or with isolated symptoms of the full-blown syndrome. Anti-NMDAR encephalitis may be related to neuromyelitis optica spectrum disorder or neurosyphilis.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico , Neurossífilis/complicações , Neurossífilis/diagnóstico , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
12.
Environ Toxicol ; 31(11): 1663-1673, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26179408

RESUMO

Uncontrolled cell proliferation is a common feature of human cancer. Some of herbal extract or plant-derived medicine had been shown as an important source of effective anticancer agents. We previously reported that an n-BuOH-soluble fraction of Kalanchoe tubiflora has antiproliferative activity by inducing mitotic catastrophe. In this study, we showed that the H2 O-soluble fraction of Kalanchoe tubiflora (KT-W) caused cell cycle arrest, and senescence-inducing activities in A549 cells. We used 2 dimensional PAGE to analyze the protein expression levels after KT-W treatment, and identified that the energy metabolism-related proteins and senescence-related proteins were disturbed. In vivo experiments showed that the tumor growths in A549-xenografted nude mice were effectively inhibited by KT-W. Our findings implied that KT-W is a putative antitumor agent by inducing cell cycle arrest and senescence. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1663-1673, 2016.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Kalanchoe , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Fitoterapia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Antonie Van Leeuwenhoek ; 107(5): 1237-47, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25726082

RESUMO

The iac locus is involved in indole-3-acetic acid (IAA) catabolism in Acinetobacter baumannii. Nine structural genes of iac are transcribed in the same direction, whereas iacR, which encodes a MarR-type transcriptional regulator, is transcribed in the opposite direction. The IacA protein, which is encoded by the second structural gene of the iac locus, is expressed in an IAA-dependent manner. Here, we characterized gene expression from this locus in wild type A. baumannii and in an iacR mutant; this revealed that the iacH promoter is negatively regulated by IacR. The transcriptional site of iacH was determined by using 5' rapid amplification of cDNA ends; one IacR-binding site was identified between positions -35 and +28 of the iacH promoter. Sequence analysis and an electrophoretic mobility shift assay indicated that recombinant IacR binds specifically to a sequence with dyad symmetry in the iacR-iacH overlapping promoters in the absence of IAA. In addition, a two-plasmid expression system in Escherichia coli showed that IAA probably serves as a ligand that binds to IacR and releases it from the iacH promoter, thereby allowing RNA polymerase to transcribe iac. Thus, iac is expressed in order to promote IAA degradation, whereas free IacR is required for iac repression. We conclude that IacR serves as a key regulator of IAA degradation in A. baumannii in the rhizosphere. These results provide new insights into the possible role of A. baumannii in the environment.


Assuntos
Acinetobacter baumannii/genética , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Ácidos Indolacéticos/metabolismo , Óperon , Acinetobacter baumannii/metabolismo , Proteínas de Bactérias/metabolismo , Sequência de Bases , Dados de Sequência Molecular , Regiões Promotoras Genéticas
14.
Neurosci Lett ; 580: 22-6, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25088691

RESUMO

Visually-induced near-infrared spectroscopy (NIRS) response was utilized to design a brain computer interface (BCI) system. Four circular checkerboards driven by distinct flickering sequences were displayed on a LCD screen as visual stimuli to induce subjects' NIRS responses. Each flickering sequence was a concatenated sequence of alternative flickering segments and resting segments. The flickering segment was designed with fixed duration of 3s whereas the resting segment was chosen randomly within 15-20s to create the mutual independencies among different flickering sequences. Six subjects were recruited in this study and subjects were requested to gaze at the four visual stimuli one-after-one in a random order. Since visual responses in human brain are time-locked to the onsets of visual stimuli and the flicker sequences of distinct visual stimuli were designed mutually independent, the NIRS responses induced by user's gazed targets can be discerned from non-gazed targets by applying a simple averaging process. The accuracies for the six subjects were higher than 90% after 10 or more epochs being averaged.


Assuntos
Interfaces Cérebro-Computador , Encéfalo/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Percepção Visual , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
15.
J Agric Food Chem ; 62(8): 1796-801, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24475736

RESUMO

Brassica oleracea deoxycytidine deaminase (BoDCD), a deoxycytidine deaminase (DCD, EC 3.5.4.14) enzyme, is known to play an important role in the Trichoderma harzianum ETS 323 mediated resistance mechanism in young leaves of B. oleracea var. capitata during Rhizoctonia solani infection. BoDCD potentially neutralizes cytotoxic products of host lipoxygenase activity, and thereby BoDCD restricts the hypersensitivity-related programmed cell death induced in plants during the initial stages of infection. To determine the biochemical characteristics and to partially elucidate the designated functional properties of BoDCD, the enzyme was cloned into an Escherichia coli expression system, and its potential to neutralize the toxic analogues of 2'-deoxycytidine (dC) was examined. BoDCD transformants of E. coli cells were found to be resistant to 2'-deoxycytidine analogues at all of the concentrations tested. The BoDCD enzyme was also overexpressed as a histidine-tagged protein and purified using nickel chelating affinity chromatography. The molecular weight of BoDCD was determined to be 20.8 kDa as visualized by SDS-PAGE. The substrate specificity and other kinetic properties show that BoDCD is more active in neutralizing cytotoxic cytosine ß-d-arabinofuranoside than in deaminating 2'-deoxycytinde to 2'-deoxyuridine in nucleic acids or in metabolizing cytidine to uridine. The optimal temperature and pH of the enzyme were 27 °C and 7.5. The Km and Vmax values of BoDCD were, respectively, 91.3 µM and 1.475 mM for its natural substrate 2'-deoxycytidine and 63 µM and 2.072 mM for cytosine ß-d-arabinofuranoside. The phenomenon of neutralization of cytotoxic dC analogues by BoDCD is discussed in detail on the basis of enzyme biochemical properties.


Assuntos
Brassica/enzimologia , Nucleosídeo Desaminases/química , Proteínas de Plantas/química , Brassica/química , Brassica/genética , Citidina/metabolismo , Citidina Desaminase , Citosina/metabolismo , Cinética , Peso Molecular , Nucleosídeo Desaminases/genética , Nucleosídeo Desaminases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especificidade por Substrato , Uridina/metabolismo
16.
Ecol Evol ; 3(13): 4310-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24340174

RESUMO

China has frequently been questioned about the data transparency and accuracy of its energy and emission statistics. Satellite-derived remote sensing data potentially provide a useful tool to study the variation in carbon dioxide (CO2) mass over areas of the earth's surface. In this study, Greenhouse gases Observing SATellite (GOSAT) tropospheric CO2 concentration data and NCEP/NCAR reanalysis tropopause data were integrated to obtain estimates of tropospheric CO2 mass variations over the surface of China. These variations were mapped to show seasonal and spatial patterns with reference to China's provincial areas. The estimates of provincial tropospheric CO2 were related to statistical estimates of CO2 emissions for the provinces and considered with reference to provincial populations and gross regional products (GRP). Tropospheric CO2 masses for the Chinese provinces ranged from 53 ± 1 to 14,470 ± 63 million tonnes were greater for western than for eastern provinces and were primarily a function of provincial land area. Adjusted for land area troposphere CO2 mass was higher for eastern and southern provinces than for western and northern provinces. Tropospheric CO2 mass over China varied with season being highest in July and August and lowest in January and February. The average annual emission from provincial energy statistics of CO2 by China was estimated as 10.3% of the average mass of CO2 in the troposphere over China. The relationship between statistical emissions relative to tropospheric CO2 mass was higher than 20% for developed coastal provinces of China, with Shanghai, Tianjin, and Beijing having exceptionally high percentages. The percentages were generally lower than 10% for western inland provinces. Provincial estimates of emissions of CO2 were significantly positively related to provincial populations and gross regional products (GRP) when the values for the provincial municipalities Shanghai, Tianjin, and Beijing were excluded from the linear regressions. An increase in provincial GRP per person was related to a curvilinear increase in CO2 emissions, this being particularly marked for Beijing, Tianjin, and especially Shanghai. The absence of detection of specific elevation of CO2 mass in the troposphere above these municipalities may relate to the rapid mixing and dispersal of CO2 emissions or the proportion of the depth of the troposphere sensed by GOSAT.

17.
Molecules ; 18(2): 1949-62, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23377135

RESUMO

Acute myeloid leukemia (AML), a very rare type of cancer, generally affects patients over 50 years old. While clinical drugs to treat advanced stages of AML exist, the disease becomes increasingly resistant to therapies. Euphorbia formosana Hayata (EF) is a native Taiwanese medicinal plant used to treat rheumatism, liver cirrhosis, herpes zoster, scabies, and photoaging, along with tumor suppression. However, the mechanisms by which it suppresses tumors have not been explored. Here, we provide molecular evidence that a hot-water extract of Euphorbia formosana (EFW) selectively inhibited the growth of human leukemic cancer cells more than other solid human cancer cell lines. Most importantly, the plant extract had limited toxicity toward healthy peripheral blood mononuclear cells (PBMCs). After THP-1 leukemic cells were treated with 50-100 µg/mL EFW for one day, the S phase DNA content of the cells increased, while treatment with 200-400 µg/mL caused the cells to accumulate in the G0/G1 phase. Notably, EFW did not affect A-549 lung cancer cells. The effectiveness of EFW against THP-1 cells may be through caspase-dependent apoptosis in leukemic cells, which is mediated through the Fas and mitochondrial pathways. The potent antileukemic activity of EFW in vitro warrants further investigation of this plant to treat leukemias and other malignancies.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Euphorbia/química , Leucemia/patologia , Mitocôndrias/metabolismo , Extratos Vegetais/farmacologia , Receptor fas/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia/enzimologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Raízes de Plantas/química , Transdução de Sinais/efeitos dos fármacos , Água
18.
J Agric Food Chem ; 60(43): 10723-32, 2012 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-23046447

RESUMO

Plant interactions with microbial biocontrol agents are used as experimental models to understand resistance-related molecular adaptations of plants. In a hydroponic three-way interaction study, a novel Trichoderma harzianum ETS 323 mediated mechanism was found to induce resistance to Rhizoctonia solani infection in Brassica oleracea var. capitata plantlets. The R. solani challenge on leaves initiate an increase in lipoxygenase activity and associated hypersensitive tissue damage with characteristic "programmed cell death" that facilitate the infection. However, B. oleracea plantlets whose roots were briefly (6 h) colonized by T. harzianum ETS 323 developed resistance to R. solani infection through a significant reduction of the host hypersensitive tissue damage. The resistance developed in the distal leaf tissue was associated with the expression of a H(2)O(2)-inducible glutathione S-transferase (BoGST), which scavenges cytotoxic reactive electrophiles, and of a deoxycytidine deaminase (BoDCD), which modulates the host molecular expression and potentially neutralizes the DNA adducts and maintains DNA integrity. The cDNAs of BoGST and BoDCD were cloned and sequenced; their expressions were verified by reverse-transcription polymerase chain reaction analysis and were found to be transcriptionally activated during the three-way interaction.


Assuntos
Brassica/enzimologia , Glutationa Transferase/genética , Nucleosídeo Desaminases/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Rhizoctonia/fisiologia , Trichoderma/fisiologia , Brassica/genética , Brassica/imunologia , Brassica/microbiologia , Citidina Desaminase , Regulação da Expressão Gênica de Plantas , Glutationa Transferase/imunologia , Nucleosídeo Desaminases/imunologia , Doenças das Plantas/genética , Proteínas de Plantas/imunologia , Rhizoctonia/imunologia
19.
Phytopathology ; 102(11): 1054-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22734558

RESUMO

ABSTRACT Previous studies have shown that the extracellular proteins of Trichoderma harzianum ETS 323 grown in the presence of deactivated Botrytis cinerea in culture include a putative l-amino acid oxidase and have suggested the involvement of this enzyme in the antagonistic mechanism. Here, we hypothesized that the mycoparasitic process of Trichoderma spp. against B. cinerea involves two steps; that is, an initial hyphal coiling stage and a subsequent hyphal coiling stage, with different coiling rates. The two-step antagonism of T. harzianum ETS 323 against B. cinerea during the mycoparasitic process in culture was evaluated using a biexponential equation. In addition, an l-amino acid oxidase (Th-l-AAO) was identified from T. harzianum ETS 323. The secretion of Th-l-AAO was increased when T. harzianum ETS 323 was grown with deactivated hyphae of B. cinerea. Moreover, in vitro assays indicated that Th-l-AAO effectively inhibited B. cinerea hyphal growth, caused cytosolic vacuolization in the hyphae, and led to hyphal lysis. Th-l-AAO also showed disease control against the development of B. cinerea on postharvest apple fruit and tobacco leaves. Furthermore, an apoptosis-like response, including the generation of reactive oxygen species, was observed in B. cinerea after treatment with Th-l-AAO, suggesting that Th-l-AAO triggers programmed cell death in B. cinerea. This may be associated with the two-step antagonism of T. harzianum ETS 323 against B. cinerea.


Assuntos
Antibiose/fisiologia , Botrytis/fisiologia , Malus/microbiologia , Nicotiana/microbiologia , Doenças das Plantas/microbiologia , Trichoderma/fisiologia , Apoptose , Agentes de Controle Biológico , Botrytis/citologia , Botrytis/crescimento & desenvolvimento , Dano ao DNA , Frutas/microbiologia , Proteínas Fúngicas/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/fisiologia , Cinética , L-Aminoácido Oxidase/isolamento & purificação , L-Aminoácido Oxidase/metabolismo , Peroxidação de Lipídeos , Potencial da Membrana Mitocondrial , Folhas de Planta/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Trichoderma/enzimologia
20.
J Agric Food Chem ; 60(10): 2464-71, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22352318

RESUMO

The monomeric L-amino acid oxidase (mTh-LAAO) of Trichoderma harzianum ETS 323 has been suggested to antagonize Rhizoctonia solani by an unknown mechanism. Here, the mTh-LAAO-treated R. solani exhibited hyphal lysis and apoptotic characteristics such as DNA fragmentation, reactive oxygen species (ROS) accumulation, lipid peroxidation, and mitochondrial membrane potential depolarization. This hyphal lysis was suppressed by the mitochondria-dependent apoptosis inhibitor oligomycin while accompanied by reduction of ROS accumulation. This result suggested that mitochondria-mediated apoptosis in R. solani was involved in mTh-LAAO-induced growth inhibition, which was supported by the evidence of cytocheome c release and activation of caspases 9 and 3. Furthermore, the data indicated that the mTh-LAAO-induced fungal cell death was also closely interrelated with the interaction of mTh-LAAO with R. solani hyphal cell wall proteins. These results illuminate the biological function and mechanism underlying the antagonistic action of T. harzianum mTh-LAAO against fungal pathogens.


Assuntos
Antibiose , Proteínas Fúngicas/metabolismo , L-Aminoácido Oxidase/metabolismo , Mitocôndrias/metabolismo , Rhizoctonia/fisiologia , Trichoderma/enzimologia , Trichoderma/fisiologia , Proteínas Fúngicas/química , L-Aminoácido Oxidase/química , Doenças das Plantas/microbiologia , Rhizoctonia/crescimento & desenvolvimento , Trichoderma/química
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