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1.
Viruses ; 16(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38932116

RESUMO

Papaya ringspot virus (PRSV) limits papaya production worldwide. Previously, we generated transgenic lines of hybrid Tainung No.2 (TN-2) carrying the coat protein (CP) gene of PRSV with broad resistance to PRSV strains. Unfortunately, all of them were female, unacceptable for growers and consumers in practical applications. With our reported flanking sequences and the newly released papaya genomic information, the CP-transgene insert was identified at a non-coding region in chromosome 3 of the papaya genome, and the flanking sequences were verified and extended. The female transgenic line 16-0-1 was first used for backcrossing with the parental Sunrise cultivar six times and then followed by selfing three times. With multi-level molecular markers developed from the PRSV CP transgene and the genomic flanking sequences, the presence and zygosity of the CP transgene were characterized at the seedling stage. Meanwhile, hermaphrodite genotype was identified by a sex-linked marker. With homozygotic transgene and horticultural properties of Sunrise, a selected hermaphrodite individual was propagated by tissue culture (TC) and used as maternal progenitor to cross with non-transgenic parental cultivar Thailand to generate a new hybrid cultivar TN-2 with a hemizygotic CP-transgene. Three selected hermaphrodite individuals of transgenic TN were micropropagated by TC, and they showed broad-spectrum resistance to different PRSV strains from Taiwan, Hawaii, Thailand, and Mexico under greenhouse conditions. The selected clone TN-2 #1, with excellent horticultural traits, also showed complete resistance to PRSV under field conditions. These selected TC clones of hermaphrodite transgenic TN-2 provide a novel cultivation system in Taiwan and elsewhere.


Assuntos
Proteínas do Capsídeo , Carica , Resistência à Doença , Doenças das Plantas , Plantas Geneticamente Modificadas , Potyvirus , Transgenes , Carica/virologia , Carica/genética , Potyvirus/genética , Plantas Geneticamente Modificadas/virologia , Resistência à Doença/genética , Doenças das Plantas/virologia , Proteínas do Capsídeo/genética , Genoma de Planta , Mapeamento Cromossômico
2.
Phytopathology ; 114(7): 1689-1700, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38451704

RESUMO

HC-Pro and coat protein (CP) genes of a potyvirus facilitate cell-to-cell movement and are involved in the systemic movement of the viruses. The interaction between HC-Pro and CP is mandatory for aphid transmission. Two turnip mosaic virus (TuMV) isolates, RC4 and YC5, were collected from calla lily plants in Taiwan. The virus derived from the infectious clone pYC5 cannot move systemically in Chenopodium quinoa plants and loses aphid transmissibility in Nicotiana benthamiana plants, like the initially isolated virus. Sequence analysis revealed that two amino acids, P5 and A206, of YC5 CP uniquely differ from RC4 and other TuMV strains. Recombination assay and site-directed mutagenesis revealed that the fifth residue of leucine (L) at the N-terminal region of the CP (TuMV-RC4), rather than proline (P) (TuMV-YC5), is critical to permit the systemic spread in C. quinoa plants. Moreover, the single substitution mutant YC5-CPP5L became aphid transmissible, similar to RC4. Fluorescence microscopy revealed that YC5-GFP was restricted in the petioles of inoculated leaves, whereas YC5-CPP5L-GFP translocated through the petioles of inoculated leaves, the main stem, and the petioles of the upper uninoculated leaves of C. quinoa plants. In addition, YC5-GUS was blocked at the basal part of the petiole connecting to the main stem of the inoculated C. quinoa plants, whereas YC5-CPP5L-GFP translocated to the upper leaves. Thus, a single amino acid, the residue L5 at the N-terminal region right before the 6DAG8 motif, is critical for the systemic translocation ability of TuMV in a local lesion host and for aphid transmissibility in a systemic host.


Assuntos
Afídeos , Proteínas do Capsídeo , Chenopodium quinoa , Nicotiana , Doenças das Plantas , Potyvirus , Afídeos/virologia , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Doenças das Plantas/virologia , Nicotiana/virologia , Potyvirus/genética , Potyvirus/fisiologia , Chenopodium quinoa/virologia , Sequência de Aminoácidos , Mutagênese Sítio-Dirigida , Folhas de Planta/virologia
3.
J Microbiol Immunol Infect ; 56(5): 996-1006, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604758

RESUMO

BACKGROUND: Accurately identifying risk factors that predict fatality in dengue is crucial for patient triage and clinical management. Our objective was to identify predictors of death associated with dengue and investigate the clinical characteristics and risk factors among patients with chronic kidney disease (CKD) who died from dengue. METHODS: A multicenter longitudinal observation study conducted from 2008 to 2019. RESULTS: A total of 1272 patients (113 who died and 1186 who recovered) diagnosed with dengue were included. Old age, CKD, and an elevated white blood cell count at hospital presentation were identified as independent predictors of in-hospital mortality among individuals infected with the dengue virus. In a subgroup analysis of 138 patients with CKD infected with dengue virus, 64 (46.3%) patients died, with 46 (33.3%) patients dying within 7 days after symptom onset. Among 64 fatal dengue patients with CKD, 34.4% were in stages 2 and 3 of kidney disease, 51.5% were in stages 4 and 5, and 14.1% had end stage renal disease as per the classification by Kidney Disease Improving Global Outcomes. Multivariate analysis revealed that initial altered consciousness, pulmonary edema, and leukocytosis during hospitalization were independently associated with in-hospital mortality in CKD patients infected with the dengue virus. Leukocytosis during hospitalization and severe hepatitis were independent risk factors for death within 7 days after dengue illness onset in CKD patients. CONCLUSIONS: This study offers valuable insights into predictors linked to fatality in dengue and reinforces the importance of optimizing patient triage to improve the quality of care.


Assuntos
Dengue , Falência Renal Crônica , Insuficiência Renal Crônica , Humanos , Adulto , Mortalidade Hospitalar , Leucocitose , Insuficiência Renal Crônica/diagnóstico , Fatores de Risco , Dengue/complicações , Estudos Retrospectivos
4.
J Microbiol Immunol Infect ; 56(5): 977-987, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37453914

RESUMO

BACKGROUND: People living with HIV (PLWH) are susceptible to non-AIDS-related events, particularly those with immunological nonresponses (INRs) to highly active antiretroviral therapy (HAART). This study assessed the association of INRs with incident non-AIDS-related events among PLWH. METHODS: This multicenter retrospective cohort study enrolled PLWH who had newly diagnosed stage 3 HIV and received HAART between January 1, 2008, and December 31, 2019. The patients were divided into two groups according to their immunological responses on the 360th day after HAART initiation: INR and non-INR groups. Cox regression and sensitivity analyses were conducted to estimate the effects of INRs on overall and individual categories of non-AIDS-related events (malignancies, vascular diseases, metabolic disorders, renal diseases, and psychiatric disorders). Patient observation started on the 360th day after HAART initiation and continued until February 28, 2022, death, or an outcome of interest, whichever occurred first. RESULTS: Among the 289 included patients, 44 had INRs. Most of the included patients were aged 26-45 years (69.55%) and were men who have sex with men (89.97%). Many patients received HIV diagnoses between 2009 and 2012 (38.54%). INRs (vs. non-INRs) were associated with composite non-AIDS-related events (adjusted hazard ratio [aHR] = 1.80; 95% confidence interval [CI]: 1.19-2.73) and metabolic disorders (aHR = 1.75; 95% CI: 1.14-2.68). Sensitivity analyses revealed consistent results for each Cox regression model for both composite non-AIDS-related events and metabolic diseases. CONCLUSION: Clinicians should be vigilant and implement early intervention and rigorous monitoring for non-AIDS-related events in PLWH with INRs to HAART.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Estudos Retrospectivos , Estudos de Coortes , Taiwan/epidemiologia , Incidência , Homossexualidade Masculina , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4
5.
BMC Infect Dis ; 23(1): 502, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525106

RESUMO

BACKGROUND: Severe dengue often leads to poor clinical outcomes and high mortality; as a result, it is of vital importance to find prognostic factors associated with the severe form of dengue. Obesity is known to deteriorate many infectious diseases due to impaired immune responses. Several studies have suggested that obese patients with dengue infection tend to have more severe manifestations with poorer prognosis. However, a firm conclusion could not be drawn due to the varied results of these studies. Here, we aimed to conduct a systematic review and meta-analysis to investigate the association between obesity and dengue severity. METHODS: A literature search for relevant studies was conducted in PubMed, Embase, Ovid Medline and Cochrane from inception to September 9, 2022. The two main keywords were "dengue" and "obesity". Mantel-Haenszel method and random effects model was used to analyze the pooled odds ratio with 95% confidence intervals. RESULTS: A total of 15 article involving a total of 6,508 patients were included in the meta-analysis. Included patients in most studies were hospitalized pediatric patients. Only one study included adulthood data. Three cohort studies, four case-control studies, and one cross-sectional studies found a significant association between obesity and dengue severity. In contrast, three cohort studies, three case-control studies, and one cross-sectional study reported no significant relationship between obesity and dengue severity. Our analysis results showed that patient with obesity is 50% (OR = 1.50; 95%CI: 1.15-1.97) more likely to develop severe manifestation of dengue. CONCLUSION: This meta-analysis revealed that overweight could be a clinical predictor for severe disease for pediatric patients with dengue infection.


Assuntos
Obesidade , Dengue Grave , Humanos , Criança , Adulto , Estudos Transversais , Obesidade/complicações , Dengue Grave/complicações , Dengue Grave/diagnóstico , Razão de Chances , Estudos de Casos e Controles
6.
Open Forum Infect Dis ; 10(6): ofad307, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383254

RESUMO

Using 3-stage pooled-plasma hepatitis C virus (HCV) RNA testing performed quarterly among at-risk people with human immunodeficiency virus (PWH), we found that if testing had been performed every 6 or 12 months, 58.6%-91.7% of PWH who recently acquired HCV would be delayed for diagnosis and might contribute to onward HCV transmission with longer durations.

7.
Viruses ; 15(4)2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37112864

RESUMO

Dengue virus (DENV) infection is a serious global health issue as it causes severe dengue hemorrhagic fever and dengue shock syndrome. Since no approved therapies are available to treat DENV infection, it is necessary to develop new agents or supplements that can do this. In this study, grape seed proanthocyanidins extract (GSPE), which is widely consumed as a dietary supplement, dose-dependently suppressed the replication of four DENV serotypes. The inhibitory mechanism demonstrated that GSPE downregulated DENV-induced aberrant cyclooxygenase-2 (COX-2) expression, revealing that the inhibitory effect of the GSPE on DENV replication involved targeting DENV-induced COX-2 expression. Mechanistic studies on signaling regulation have demonstrated that GSPE significantly reduced COX-2 expression by inactivating NF-κB and ERK/P38 MAPK signaling activities. Administrating GSPE to DENV-infected suckling mice reduced virus replication, mortality, and monocyte infiltration of the brain. In addition, GSPE substantially reduced the expression of DENV-induced inflammatory cytokines associated with severe dengue disease, including tumor necrosis factor-α, nitric oxide synthase, interleukin (IL)-1, IL-6, and IL-8, suggesting that GSPE has potential as a dietary supplement to attenuate DENV infection and severe dengue.


Assuntos
Vírus da Dengue , Dengue , Dengue Grave , Camundongos , Animais , NF-kappa B/metabolismo , Ciclo-Oxigenase 2/genética , Vírus da Dengue/fisiologia , Dengue Grave/tratamento farmacológico , Replicação Viral
8.
Plant Dis ; 107(6): 1757-1768, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36401850

RESUMO

Cross protection application of HA5-1, an attenuated mutant of papaya ringspot virus (PRSV) HA strain from Hawaii, was withdrawn from Taiwan due to the narrow geographic strain specificity of HA5-1. Here, to overcome this problem, we created attenuated mutants of PRSV YK, a dominant severe strain from Taiwan, by mutating helper component protease (HC-Pro) at F7, R181, F206, and D397 residues critical for potyviral pathogenicity. PRSV YK HC-Pro R181I, F206L, and D397N single-mutant viruses induced mild symptoms, but their adverse effects on growth of papaya plants disqualified them as useful protective viruses. However, F7I single-mutant and F7I + F206L double-mutant viruses displayed mild symptoms followed by recovery, and they showed a zigzag pattern of accumulation in papaya plants, indicating their potential to trigger RNA silencing and retain partial antagonistic suppression of host defense. Although F7I + R181I and F7I + D397N double-mutant viruses caused symptomless infection, they accumulated barely above mock level and, thus, were not qualified as proper protective viruses. RNA silencing suppression (RSS) analysis by agroinfiltration in Nicotiana benthamiana plants revealed that the HC-Pro F7I and F7I + F206L mutant proteins were weaker in RSS ability than the wild-type protein. Under greenhouse conditions, F7I and F7I + F206L mutant viruses were genetically stable but not aphid transmissible. Compared with the HA5-1 mutant's low degree (10%) of protection to papaya plants, the F7I and F7I + F206L mutants provided complete (100%) protection to papaya and horn melon plants against strain YK. Thus, F7I and F7I + F206L mutants solve the problem of strain-specific protection and have great potential for control of PRSV in Taiwan.


Assuntos
Proteção Cruzada , Proteínas Virais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Cisteína Endopeptidases/metabolismo
9.
New Phytol ; 237(4): 1215-1228, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36377104

RESUMO

Phosphate (Pi) availability is a major factor limiting plant growth and development. The key transcription factor controlling Pi-starvation response (PSR) is PHOSPHATE STARVATION RESPONSE 1 (PHR1) whose transcript levels do not change with changes in Pi levels. However, how PHR1 stability is regulated at the post-translational level is relatively unexplored in Arabidopsis thaliana. Inositol polyphosphates (InsPn) are important signal molecules that promote the association of stand-alone SPX domain proteins with PHR1 to regulate PSR. Here, we show that NITROGEN LIMITATION ADAPTATION (NLA) E3 ligase can associate with PHR1 through its conserved SPX domain and polyubiquitinate PHR1 in vitro. The association with PHR1 and its ubiquitination is enhanced by InsP6 but not by InsP5. Analysis of InsPn-related mutants and an overexpression plant shows PHR1 levels are more stable in itpk4-1 and vih2-4/VIH1amiRNA but less stable in ITPK4 overexpression plants. Under Pi-deficient conditions, nla seedlings contain high PHR1 levels, display long root hair and accumulate anthocyanin in shoots phenocopying PHR1 overexpression plants. By contrast, NLA overexpression plants phenocopy phr1 whose phenotypes are opposite to those of nla. Our results suggest NLA functions as a negative regulator of Pi response by modulating PHR1 stability and the NLA/PHR1 association depends on InsPn levels.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Polifosfatos/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
10.
J Microbiol Immunol Infect ; 56(2): 267-273, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36055945

RESUMO

BACKGROUND: Obesity is associated with unfavorable outcomes for infectious diseases. Most researches exploring the association between nutritional status and dengue severity have focused on pediatric populations, with only few studies assessing adult patients. METHODS: Adult patients with laboratory-confirmed dengue admitted to a tertiary hospital in southern Taiwan between 2014 and 2015 were enrolled retrospectively. Demographics, comorbidities, clinical presentation, laboratory findings, and outcomes were obtained from case-record forms. Patients were categorized into obese group and nonobese group. The obese group comprised patients with a body mass index of ≥27.5 kg/m2. RESULTS: A total of 1417 hospitalized patients with dengue were evaluated. The mean age was 57.9 years (range: 18-92 years). The obese and nonobese groups comprised 333 (23.5%) and 1084 (76.5%) patients, respectively. The obese group included more patients with hypertension (85%, p < 0.001), diabetes mellitus (33%, p < 0.001), and congestive heart failure (6.3%, p = 0.049). Multivariate analysis revealed that the obese group had more petechiae (AOR: 1.353, 95% CI: 1.025-1.786, p = 0.033), more dyspnea (AOR: 1.380, 95% CI: 1.015-1.876, p = 0.040), and more severe hepatitis (AOR: 2.061, 95% CI: 1.050-4.048, p = 0.036). The obese group also had higher peak hematocrit values (44.1%, p < 0.001) and lower nadir platelet count (45.3 × 103/µL, p = 0.049) than the nonobese group. CONCLUSION: In adult patients with dengue, obese group had more petechiae, dyspnea, severe hepatitis, lower nadir of platelet count, and higher peak hematocrit level. We observed no difference in severe dengue or mortality between obese and nonobese group.


Assuntos
Dengue , Dengue Grave , Criança , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Obesidade/complicações , Obesidade/epidemiologia , Dengue Grave/complicações , Dengue Grave/epidemiologia , Comorbidade , Hospitalização , Dengue/complicações , Dengue/epidemiologia
11.
Antiviral Res ; 207: 105400, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36055433

RESUMO

Dengue virus (DENV) infection is a life-threatening disease that causes severe dengue hemorrhagic fever and dengue shock syndrome. There is currently no effective therapeutic agent or widely used vaccine for treating DENV infections. In this study, sulforaphane (SFN), an antioxidant phytocompound, exhibited significant antiviral activity, with a half-inhibitory concentration value of 5.8 ± 0.7 µM to suppress viral RNA replication. Mechanistic studies demonstrated that SFN-induced heme oxygenase-1 (HO-1) expression, which inhibited viral protease activity, leading to the restoration of antiviral interferon (IFN) responses against DENV replication. Its antiviral activity can be attenuated by the knockdown of HO-1 expression by short hairpin RNA and blockage of activity with a specific inhibitor, supporting the contention that HO-1 induction contributes to the anti-DENV activity of SFN. SFN also stimulated HO-1 induction through an Nrf2-dependent pathway. SFN effectively prolonged the survival rate and reduced the virus titer in DENV-infected ICR suckling mice with activated expression of interferon-stimulated genes. The anti-DENV activity of SFN was also observed in the IFN-deficient AG129 mouse model. Collectively, SFN represents significant anti-DENV activity in vitro and in vivo and is a promising drug candidate or dietary supplement against DENV.


Assuntos
Vírus da Dengue , Dengue , Animais , Antioxidantes/farmacologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Dengue/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Interferons/farmacologia , Isotiocianatos , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2 , Peptídeo Hidrolases , RNA Interferente Pequeno/farmacologia , RNA Viral , Sulfóxidos , Proteases Virais , Replicação Viral
12.
Emerg Microbes Infect ; 11(1): 1867-1875, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35811508

RESUMO

Candida auris, a multidrug resistant pathogenic yeast, has spread worldwide and caused several outbreaks in healthcare settings. Here, we report the first case of C. auris candidemia in Taiwan in a patient with a two-month history of hospitalization in Vietnam. We performed further investigation on the isolate from the present case as well as the previously reported C. auris isolate identified from a wound in 2018 in Taiwan, which was the first case reported in Taiwan. Both C. auris isolates were found to be susceptible to fluconazole, amphotericin B, and echinocandins. Additionally, mutations in ERG11 or FKS1 were not detected in either isolate. Microsatellite genotyping revealed that both isolates belonged to the South Asian clade. In recent years, C. auris has emerged as a global concern, and differences in clades and susceptibility patterns mandate further awareness and systematic surveillance.


Assuntos
Candida auris , Candidíase Invasiva , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida/genética , Candidíase , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Taiwan/epidemiologia
13.
Travel Med Infect Dis ; 47: 102281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35231642

RESUMO

BACKGROUND: As cardiac involvement can cause serious complications and death, understanding its role in acute dengue and influenza virus infections is important. METHODS: We provide a comparative evaluation of severe dengue and critically ill influenza patients with elevated cardiac troponin-I (cTnI) from 2014 to 2019. Inclusion criteria included patients in which cTnI test were ordered. Patient without cTnI test was excluded. RESULTS: During the study period, 82 (41 severe dengue and 41 critically ill influenza) patients had cTnI elevations, and 81 (35 severe dengue and 46 critically ill influenza) patients had a single normal cTnI test. Severe dengue patients with cTnI elevations had a significantly higher incidences of acute kidney injury, gastrointestinal bleeding, early mortality (≤7 after illness onset) and in-hospital mortality than those with severe dengue and single normal cTnI test. Significantly higher aspartate aminotransferase (AST) levels and higher incidence of gastrointestinal bleeding was observed in critically ill influenza patients with cTnI elevations compared to critically ill influenza patients with single normal cTnI measurement. Of the patients with cTnI elevations, the early and in-hospital mortality rates were 53.6% and 65.8%, respectively, in severe dengue patients, and 7.3% and 46.3%, respectively, in critically ill influenza patients. Significantly higher early mortality rates were observed in severe dengue patients with elevated cTnI levels than in critically ill influenza patients with cTnI elevations. Critically ill influenza patients with elevated cTnI levels had significantly higher incidences of pneumonia, pneumothorax, and bacteremia than severe dengue patients with cTnI elevations. Multivariate analysis revealed elevated AST (>1000U/L) (95% confidence interval [CI]: 1.690-143.174) was an independent risk factor for in-hospital mortality in severe dengue patients with elevated cTnI levels. Leukocytosis (95% CI: 1.079-1.124) and thrombocytopenia (95% CI: 2.739-5.821) were independently correlated with in-hospital mortality in critically ill influenza patients with cTnI elevations. CONCLUSIONS: Differences in clinical features between severe dengue and critically ill influenza patients with cTnI elevations. High early mortality rate was observed in severe dengue patients with cardiac involvement. In contrast, most critically ill influenza patients died ≥2 weeks after the onset of illness, regardless of cTnI elevations. Our report has important clinical implications for the timely recognition and management of cardiac complication in patients with acute dengue and influenza virus infections.


Assuntos
Influenza Humana , Dengue Grave , Biomarcadores , Estudos de Coortes , Estado Terminal , Hemorragia Gastrointestinal , Humanos , Influenza Humana/complicações , Influenza Humana/epidemiologia , Prognóstico , Dengue Grave/complicações , Dengue Grave/epidemiologia , Troponina I
14.
Mol Plant Pathol ; 23(7): 947-965, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35285990

RESUMO

Control of plant viruses by cross-protection is limited by the availability of effective protective strains. Incorporation of an NIa-protease processing site in the extreme N-terminal region of the helper component protease (HC-Pro) of turnip mosaic virus (TuMV) resulted in a mutant virus TuHND I that induced highly attenuated symptoms. Recombination analysis verified that two variations, F7I mutation and amino acid 7-upstream-deletion, in HC-Pro co-determined TuHND I attenuation. TuHND I provided complete protection to Nicotiana benthamiana and Brassica campestris subsp. chinensis plants against infection by the severe parental strain. Aphid transmission tests revealed that TuHND I was not aphid-transmissible. An RNA silencing suppression (RSS) assay by agroinfiltration suggested the RSS-defective nature of the mutant HC-Pro. In the context (amino acids 3-17) encompassing the two variations of HC-Pro, we uncovered an FWKG-α-helix 1 (αH1) element that influenced the functions of aphid transmission and RSS, whose motifs were located far downstream. We further demonstrated that HC-Pro F7 was a critical residue on αH1 for HC-Pro functions and that reinstating αH1 in the RSS-defective HC-Pro of TuHND I restored the protein's RSS function. Yeast two-hybrid and bimolecular fluorescence complementation assays indicated the FWKG-αH1 element as an integral part of the HC-Pro self-interaction domain. The possibility of regulation of the mechanistically independent functions of RSS and aphid transmission by the FWKG-αH1 element is discussed. Extension of TuMV HC-Pro FWKG-αH1 variations to another potyvirus, zucchini yellow mosaic virus, also generated nonaphid-transmissible cross-protective mutant viruses. Hence, the modification of the FWKG-αH1 element can generate effective attenuated viruses for the control of potyviruses by cross-protection.


Assuntos
Afídeos , Potyvirus , Animais , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Doenças das Plantas/prevenção & controle , Potyvirus/fisiologia , Proteínas Virais
15.
Front Plant Sci ; 12: 746586, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745179

RESUMO

We have developed a rapid Raman spectroscopy-based method for the detection and quantification of early innate immunity responses in Arabidopsis and Choy Sum plants. Arabidopsis plants challenged with flg22 and elf18 elicitors could be differentiated from mock-treated plants by their Raman spectral fingerprints. From the difference Raman spectrum and the value of p at each Raman shift, we derived the Elicitor Response Index (ERI) as a quantitative measure of the response whereby a higher ERI value indicates a more significant elicitor-induced immune response. Among various Raman spectral bands contributing toward the ERI value, the most significant changes were observed in those associated with carotenoids and proteins. To validate these results, we investigated several characterized Arabidopsis pattern-triggered immunity (PTI) mutants. Compared to wild type (WT), positive regulatory mutants had ERI values close to zero, whereas negative regulatory mutants at early time points had higher ERI values. Similar to elicitor treatments, we derived an analogous Infection Response Index (IRI) as a quantitative measure to detect the early PTI response in Arabidopsis and Choy Sum plants infected with bacterial pathogens. The Raman spectral bands contributing toward a high IRI value were largely identical to the ERI Raman spectral bands. Raman spectroscopy is a convenient tool for rapid screening for Arabidopsis PTI mutants and may be suitable for the noninvasive and early diagnosis of pathogen-infected crop plants.

16.
Can J Infect Dis Med Microbiol ; 2021: 9916642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422144

RESUMO

In 2014 and 2015, Southern Taiwan experienced two unprecedented outbreaks, with more than 10,000 laboratory-confirmed dengue cases in each outbreak. The present study was aimed to investigate the influence of meteorological and spatial factors on dengue outbreaks in Southern Taiwan and was conducted in Kaohsiung City, which is the most affected area in Taiwan. The distributed lag nonlinear model was used to investigate the role of climatic factors in the 2014 and 2015 dengue outbreaks. Spatial statistics in the Geographic Information System was applied to study the relationship between the dengue spreading pattern and locations of traditional markets (human motility) in the 2015 dengue outbreak. Meteorological analysis results suggested that the relative risk of dengue fever increased when the weekly average temperature was more than 15°C at lagged weeks 5 to 18. Elevated relative risk of dengue was observed when the weekly average rainfall was more than 150 mm at lagged weeks 12 to 20. The spatial analysis revealed that approximately 83% of dengue cases were located in the 1000 m buffer zone of traditional market, with statistical significance. These findings support the influence of climatic factors and human motility on dengue outbreaks. Furthermore, the study analysis may help authorities to identify hotspots and decide the timing for implementation of dengue control programs.

17.
Expert Rev Anti Infect Ther ; 19(12): 1495-1502, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34182875

RESUMO

Introduction: Dengue virus is a global health threat, with approximately 390 million dengue infections annually. Efficient vaccines for dengue prevention are currently lacking. This review aims to summarize the current progress in dengue vaccine development.Area covered: This article discusses recent dengue vaccine developments based on the published literature and ClinicalTrials.gov website up to December 2020.Expert opinion: The first live-attenuated chimeric yellow-fever/tetravalent dengue vaccine (CYD-TDV), Dengvaxia, has been licensed in several countries. However, the low efficacy of this vaccine was observed in children and dengue-naïve individuals. It also increased the risk of severe dengue in people who had not been exposed to dengue. The heterologous prime-boost regimen of sequential immunization with DENVax and Dengvaxia covers four serotypes of immunogenicity, eliminating the effect of ADE. Moreover, a heterologous prime-boost regimen that combines inactivated vaccines with alum and live attenuated vaccines might increase the immunogenic response. The lack of an ideal animal model is an obstacle to the development of dengue vaccines, and the macaque model may be considered for similar immunologic responses in humans.


Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Dengue Grave , Animais , Anticorpos Antivirais , Dengue/prevenção & controle , Humanos , Vacinas Atenuadas
18.
J Microbiol Immunol Infect ; 54(5): 885-892, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33840603

RESUMO

BACKGROUND: Intracranial hemorrhage (ICH) or infarction in dengue cases is rare but very challenging for clinicians. We report these uncommon complications of dengue patients and focused on the significant factors associated with ICH or infarction in dengue patients. METHODS: This investigation was a retrospective study of 182 adult dengue patients who received brain computed tomography at three Taiwan hospitals during the 2014 and 2015 dengue outbreaks. This included 13 hemorrhage cases, 26 infarction cases and 143 cases without brain infarction or hemorrhage. RESULTS: Among them, 13 (7.14%) suffered from ICH (6 had subdural hemorrhage, 3 had subarachnoid hemorrhage, 1 had subdural and subarachnoid hemorrhage, and 3 had intracerebral hemorrhage) and 26 (14.3%) had brain infarction. The overall mortality rate was 4/13 (30.8%) in the ICH group and 3/26 (11.5%) in the infarction group. The significant variables from the univariate analysis, including difference between 2014 and 2015, age, history of cerebrovascular accident, bone pain, arthralgia, dizziness, altered consciousness, and a higher Charlson comorbidity score. Multivariate analysis revealed that significant risk factors for ICH/infarction in dengue cases were the year of occurrence, 2014 vs. 2015 (p < 0.0001, OR = 25.027, 95% CI = 8.205-76.336), Charlson score >4 (p = 0.01, OR = 3.764, 95% CI = 1.364-10.386) and altered consciousness (p < 0.0001, OR = 6.3, 95% CI = 2.242-17.7). The factors physicians should notice in dengue endemic regions for brain infarction or ICH include altered consciousness and a Charlson score >4, especially in the year that a higher frequency of infarction/ICH was observed.


Assuntos
Infarto Encefálico/epidemiologia , Dengue/epidemiologia , Hemorragias Intracranianas/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Infarto Encefálico/patologia , Dengue/patologia , Feminino , Humanos , Hemorragias Intracranianas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia
19.
Front Immunol ; 12: 599345, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659001

RESUMO

Exposure to environmental hormones such as di(2-ethylhexyl) phthalate (DEHP) has become a critical human health issue globally. This study aimed to investigate the correlations between DEHP/mono-(2-ethylhexyl) phthalate (MEHP) levels and macrophage-associated immune responses and clinical manifestations in dengue virus (DV)-infected patients. Among 89 DV-infected patients, those with DV infection-related gastrointestinal (GI) bleeding (n = 13, 15% of patients) had significantly higher DEHP exposure than those without GI bleeding (n = 76, 85% of patients), which were 114.2 ng/ml versus 52.5 ng/ml ΣDEHP in urine; p = 0.023). In an in vitro study using cultured human monocyte-derived macrophages (MDMs) to investigate the effects of MEHP, treatment increased IL-1ß and TNF-α release but decreased IL-23 release, with negative correlations observed between urine ΣDEHP and serum IL-23 levels in patients. MEHP-treated MDMs had lower antiviral Th17 response induction activity in mixed T-cell response tests. The in vitro data showed that MEHP increased DV viral load and decreased IL-23 release dose-dependently, and adding IL-23 to MEHP-exposed MDMs significantly reduced the DV viral load. MEHP also suppressed IL-23 expression via the peroxisome proliferator-activated receptor-gamma (PPAR-γ) pathway. Further, the PPAR-γ antagonist GW9662 significantly reversed MEHP-induced IL-23 suppression and reduced the DV viral load. These study findings help to explain the associations between high MEHP levels and the high global burden of dengue disease.


Assuntos
Antivirais , Vírus da Dengue/imunologia , Dengue/imunologia , Dietilexilftalato/análogos & derivados , Interleucina-23/imunologia , Macrófagos/imunologia , Adulto , Idoso , Antivirais/efeitos adversos , Antivirais/farmacologia , Dengue/tratamento farmacológico , Dengue/patologia , Dietilexilftalato/efeitos adversos , Dietilexilftalato/farmacologia , Feminino , Humanos , Interleucina-1beta/imunologia , Macrófagos/fisiologia , Macrófagos/virologia , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/imunologia
20.
Sci Rep ; 10(1): 20206, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214575

RESUMO

Precision agriculture requires new technologies for rapid diagnosis of plant stresses, such as nutrient deficiency and drought, before the onset of visible symptoms and subsequent yield loss. Here, we demonstrate a portable Raman probe that clips around a leaf for rapid, in vivo spectral analysis of plant metabolites including carotenoids and nitrates. We use the leaf-clip Raman sensor for early diagnosis of nitrogen deficiency of the model plant Arabidopsis thaliana as well as two important vegetable crops, Pak Choi (Brassica rapa chinensis) and Choy Sum (Brassica rapa var. parachinensis). In vivo measurements using the portable leaf-clip Raman sensor under full-light growth conditions were consistent with those obtained with a benchtop Raman spectrometer measurements on leaf-sections under laboratory conditions. The portable leaf-clip Raman sensor offers farmers and plant scientists a new precision agriculture tool for early diagnosis and real-time monitoring of plant stresses in field conditions.


Assuntos
Arabidopsis/metabolismo , Brassica rapa/metabolismo , Produtos Agrícolas/metabolismo , Folhas de Planta/metabolismo , Análise Espectral Raman/instrumentação , Estresse Fisiológico/fisiologia , Proteínas de Plantas/metabolismo
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