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Erysiphe corylacearum has recently been reported in northern Italy (Piedmont) and other European countries as the causal agent of a new emerging powdery mildew on hazelnut. This disease is much more dangerous than the common hazelnut powdery mildew caused by Phyllactinia guttata as it significantly reduces yield and quality of hazelnuts. This study aimed to perform morphological and molecular characterization of the fungal isolates from powdery mildew-infected plants in the Piedmont Italian region. Additionally, genetic diversity studies and pathogenicity tests were conducted. Thirty-six fungal isolates originating from symptomatic hazelnut plants exhibiting specific powdery mildew symptoms on the superior leaf side were identified morphologically as E. corylacearum. Single- and multilocus sequence typing of five loci (ITS, rpb2, CaM, GAPDH and GS) assigned all isolates as E. corylacearum. Multilocus and GAPDH phylogenetic studies resulted in the most efficient characterization of E. corylacearum. Studied fungal isolates were able to cause new emerging powdery mildew disease by fulfilling Koch's postulates. The emergence of powdery mildew disease in Italy revealed the E. corylacearum subgrouping, population expansion, and high nucleotide similarity with other recently identified E. corylacearum hazelnut isolates. To contain this harmful disease and inhibit the fungus spread into new geographical zones, it will be necessary to implement more rigorous monitoring in neighboring hazelnut plantations near infected hazelnuts, use sustainable fungicides and search for new biocontrol agents.
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Corylus , Erysiphe , Filogenia , Doenças das Plantas , Corylus/microbiologia , Itália , Doenças das Plantas/microbiologia , Erysiphe/genética , Tipagem de Sequências Multilocus , Variação Genética , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Ascomicetos/patogenicidadeRESUMO
PURPOSE: To describe and validate a 3D-printed adapter tool which could be used with either a slit lamp or a condensing lens, interchangeable between devices through magnetic fastening, in order to provide physicians a quick, easy and effective method of obtaining clinical photos. MATERIALS AND METHODS: Three specialists, with at least 4-year experience in ophthalmology, gave a rate of image quality obtained by our device and the diagnostic confidence grade. The 3 specialists conducted each 13 or 14 examinations with the smartphone and magnetic adapter. At the end of evaluation, they rated with the Likert scale the ease of use of the device in obtaining clinical images of the anterior segment and ocular fundus respectively. RESULTS: Data of quality perception and confidence demonstrated high values not dissimilar to the "de visu" eye examination. Moreover the instrument we designed turned out to be very user friendly. CONCLUSION: Our adapter coupled with a modern smartphone was able to obtain 4k images and videos of anterior segment, central and peripheral fundus, in an easy and inexpensive way.
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Tomato leaf curl New Delhi virus (ToLCNDV) represents a threat to economically important horticultural crops. A real-time loop-mediated isothermal amplification (LAMP) assay for in-field ToLCNDV detection was developed, coupled to a rapid sample preparation method, and tested both in field and laboratory conditions on zucchini squash, tomato, and pepper samples. A set of six LAMP primers was designed for specific ToCLNDV detection, targeting a 218-nucleotide sequence within the AV1 gene. The sensitivity, specificity and accuracy of the real-time LAMP assay and comparison with canonical PCR were evaluated. The real-time LAMP assay developed was about one-thousand times more sensitive than the conventional PCR method, detecting a total of 4.41 × 102 genome copies as minimum target; no cross-reactivity was detected with the other geminiviruses used as the outgroup. The rapid sample preparation method allows for a reliable detection with a low reaction delay (≈2-3 min) compared to canonical DNA extraction, providing results in less than 45 min. Lastly, an increase in ToLCNDV-positive sample detection was observed compared to PCR, in particular for asymptomatic plants (85% and 71.6%, respectively). The real-time LAMP assay developed is a rapid, simple, specific, and sensitive technique for ToLCNDV detection, and it can be adopted as a routine test, for both in-field and laboratory conditions.
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Inflammatory burden is associated with COVID-19 severity and outcomes. Residual computed tomography (CT) lung abnormalities have been reported after COVID-19. The aim was to evaluate the association between inflammatory burden during COVID-19 and residual lung CT abnormalities collected on follow-up CT scans performed 2-3 and 6-7 months after COVID-19, in severe COVID-19 pneumonia survivors. C-reactive protein (CRP) curves describing inflammatory burden during the clinical course were built, and CRP peaks, velocities of increase, and integrals were calculated. Other putative determinants were age, sex, mechanical ventilation, lowest PaO2/FiO2 ratio, D-dimer peak, and length of hospital stay (LOS). Of the 259 included patients (median age 65 years; 30.5% females), 202 (78%) and 100 (38.6%) had residual, predominantly non-fibrotic, abnormalities at 2-3 and 6-7 months, respectively. In age- and sex-adjusted models, best CRP predictors for residual abnormalities were CRP peak (odds ratio [OR] for one standard deviation [SD] increase = 1.79; 95% confidence interval [CI] = 1.23-2.62) at 2-3 months and CRP integral (OR for one SD increase = 2.24; 95%CI = 1.53-3.28) at 6-7 months. Hence, inflammation is associated with short- and medium-term lung damage in COVID-19. Other severity measures, including mechanical ventilation and LOS, but not D-dimer, were mediators of the relationship between CRP and residual abnormalities.
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COVID-19/patologia , Pneumonia/diagnóstico por imagem , Idoso , Proteína C-Reativa/análise , COVID-19/complicações , COVID-19/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Pneumonia/etiologia , Pneumonia/patologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
A real-time loop-mediated isothermal amplification (LAMP) assay was developed for simple, rapid and efficient detection of the Olea europaea geminivirus (OEGV), a virus recently reported in different olive cultivation areas worldwide. A preliminary screening by end-point PCR for OEGV detection was conducted to ascertain the presence of OEGV in Sicily. A set of six real-time LAMP primers, targeting a 209-nucleotide sequence elapsing the region encoding the coat protein (AV1) gene of OEGV, was designed for specific OEGV detection. The specificity, sensitivity, and accuracy of the diagnostic assay were determined. The LAMP assay showed no cross-reactivity with other geminiviruses and was allowed to detect OEGV with a 10-fold higher sensitivity than conventional end-point PCR. To enhance the potential of the LAMP assay for field diagnosis, a simplified sample preparation procedure was set up and used to monitor OEGV spread in different olive cultivars in Sicily. As a result of this survey, we observed that 30 out of 70 cultivars analyzed were positive to OEGV, demonstrating a relatively high OEGV incidence. The real-time LAMP assay developed in this study is suitable for phytopathological laboratories with limited facilities and resources, as well as for direct OEGV detection in the field, representing a reliable method for rapid screening of olive plant material.
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Mesotelioma , Feminino , Humanos , Menopausa , Mesotelioma/cirurgia , Pelve , Peritônio , ÚteroRESUMO
Resumen INTRODUCCIÓN: La tuberculosis sigue siendo un problema de salud pública global: alrededor de un cuarto de la población mundial está infectada con el bacilo de la tuberculosis, pero solo 5 a 15% realmente resultarán con la enfermedad. Pese a los esfuerzos por controlar la infección, hoy en día es la principal causa de muerte producida por un único agente infeccioso. La forma extrapulmonar es rara, y la genital suele manifestarse con esterilidad, en otros simula un cáncer de ovario avanzado, incluidas la masa anexial y la ascitis, pérdida de peso y elevación del marcador tumoral Ca125. El diagnóstico diferencial prequirúrgico es complejo, de ahí que a la mayoría de las pacientes se les indique una intervención quirúrgica innecesaria. CASO CLÍNICO: Paciente de 29 años con diagnóstico de formación anexial sospechosa de malignidad que se trató de manera conservadora hasta conseguir su regresión total. Además, se efectuó una revisión de la bibliografía relacionada con esta infrecuente entidad. CONCLUSIÓN: La conjunción de ascitis, masa pélvica y elevación del marcador Ca125 puede corresponder al diagnóstico de cáncer de ovario avanzado, ello sin olvidar la posibilidad de tuberculosis extraperitoneal en pacientes con antecedente de tuberculosis o procedentes de zonas endémicas. El diagnóstico es complejo, sobre todo por la baja incidencia en nuestro medio, que a menudo requiere laparoscopias exploradoras para confirmar el origen de las lesiones.
Abstract INTRODUCTION: Tuberculosis remains a global public health problem: about a quarter of the world's population is infected with the tuberculosis bacillus, but only 5-15% will actually develop the disease. Despite efforts to control the infection, today it is the leading cause of death from a single infectious agent. The extrapulmonary form is rare, and the genital form usually manifests with sterility, in others it simulates advanced ovarian cancer, including adnexal mass and ascites, weight loss and elevation of the tumor marker Ca125. The pre-surgical differential diagnosis is complex, hence most patients are indicated for unnecessary surgery. CLINICAL CASE: A 29-year-old patient with a diagnosis of adnexal formation suspicious for malignancy was treated conservatively until complete regression was achieved. In addition, a review of the existing literature related to this rare entity was performed. CONCLUSION: The conjunction of ascites, pelvic mass and elevated Ca125 marker may correspond to the diagnosis of advanced ovarian cancer, without forgetting the possibility of extraperitoneal tuberculosis in patients with a history of tuberculosis or from endemic areas. Diagnosis is complex, especially due to the low incidence in our environment, which often requires exploratory laparoscopy to confirm the origin of the lesions.
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Resumen OBJETIVO: Exponer los desenlaces quirúrgicos de las pacientes intervenidas por cáncer de endometrio, analizar si existen puntos de mejora en nuestra práctica clínica y aportar más datos a la evidencia publicada, para ayudar al avance en el tratamiento quirúrgico de las pacientes con esta enfermedad MATERIALES Y MÉTODOS: Estudio observacional, descriptivo y retrospectivo llevado a cabo en la Unidad de Oncología Ginecológica del Hospital Regional Virgen Macarena de Sevilla, España, entre junio de 2013 y febrero de 2020. Se reunieron los reportes quirúrgicos de pacientes intervenidas por alguna afección endometrial premaligna o maligna. Variables de estudio: edad, IMC, cirugías previas, diagnóstico histopatológico y estadio, vía de acceso quirúrgico y terapia coadyuvante. Se exponen los desenlaces relacionados con complicaciones quirúrgicas y tasa de curación, así como el tiempo de intervención, vía de acceso quirúrgico y estancia hospitalaria. RESULTADOS: Se estudiaron 250 pacientes, la mayoría (76%) con diagnóstico de adenocarcinoma endometrioide de endometrio. La vía de acceso quirúrgico más utilizada fue la laparoscopia (51.6%), con un porcentaje de complicaciones intraoperatorias del 10% y posoperatorias del 9.2%. El 88.4% de las pacientes permanece viva y libre de enfermedad después del tratamiento, con recaídas solo en el 11.6% y 8% de fallecimientos. CONCLUSIONES: El tratamiento inicial de elección, en pacientes con hiperplasia con atipias o cáncer de endometrio en estadios tempranos, es la cirugía, mediante histerectomía, doble anexectomía y en algunos casos linfadenectomía asociada. La elección de la vía quirúrgica de acceso debe individualizarse a las condiciones particulares de cada paciente. La laparoscopia ofrece múltiples ventajas, es una técnica en auge y cada día más practicada.
Abstract OBJECTIVE: To expose the surgical outcomes of patients operated on for endometrial cancer, to analyze if there are points of improvement in our clinical practice and to contribute more data to the published evidence, to help advance the surgical treatment of patients with this disease. MATERIALS AND METHODS: Observational, descriptive, and retrospective study carried out in the Gynecologic Oncology Unit of the Virgen Macarena Regional Hospital of Seville, Spain, between June 2013 and February 2020. Surgical reports of patients operated on for any premalignant or malignant endometrial condition were collected. Study variables: age, BMI, previous surgeries, histopathological diagnosis and stage, surgical access route and adjuvant therapy. Outcomes related to surgical complications and cure rate are presented, as well as operation time, surgical access route and hospital stay. RESULTS: 250 patients were studied, the majority (76%) with a diagnosis of endometrioid endometrial adenocarcinoma. The most used surgical access route was laparoscopy (51.6%), with a percentage of intraoperative complications of 10% and postoperative complications of 9.2%. 88.4% of patients remain alive free of disease after treatment, with relapses in only 11.6% and 8% deaths. CONCLUSIONS: The initial treatment of choice in patients with hyperplasia with atypia or early-stage endometrial cancer is surgery, by hysterectomy, double adnexectomy and in some cases associated lymphadenectomy. The choice of surgical approach must be individualized to the conditions of each patient. Laparoscopy offers multiple advantages; it is a technique that is on the rise and is being used more and more frequently.
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Parietaria mottle virus (PMoV) is considered an emerging virus in many countries of the Mediterranean basin, especially on tomato and pepper crops. Symptoms on tomato leaves and fruits can be easily confused with those induced by cucumber mosaic virus (CMV) with necrogenic satellite RNA (CMV-satRNA), tomato spotted wilt virus (TSWV) or tomato mosaic virus (ToMV). Mixed infection of these viruses has been also reported in some tomato cultivars, with an increase in the complexity of the symptoms and severity of the disease. Although a specific serum and riboprobes have been produced, nowadays no sensitive diagnostic methods are available for the rapid PMoV detection. Here, we have developed a RT-qPCR assay with the aim to establish a more sensitive and specific method for PMoV detection. Specific primers and TaqMan probe were designed and in silico tested with all PMoV isolates available in GenBank. Moreover, this method was evaluated on tomato naturally infected samples from Sicily region (Italy). Results obtained showed that the RT-qPCR assay developed in this work is extremely sensitive, in fact, it is able to detect as few as 10 PMoV RNA copies in tomato total RNA; moreover, it will be a particularly valuable tool for early detection of PMoV. Furthermore, the analyzes on field samples show how this pathogen is increasingly present in tomato crops in the last years, helping to undermine the Italian horticultural sector.
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BACKGROUND: Cervical competence is currently conceived as a continuous biological process with progressive degrees of insufficiency, this substituting the traditional vision of cervical competence as being present or absent. The most extreme expression of cervical insufficiency is known as "hourglass membranes". Currently no consensus exists regarding the treatment of pregnancies complicated by the protrusion of amniotic membranes; however, the majority of authors agree on recommending bed rest and performing cervical cerclage, known as "emergent cerclage." METHODS: We describe a series of clinical cases corresponding to second-trimester pregnancies with cervical dilation and prolapsed amniotic membranes that were admitted to our hospital, managed with conservative treatment. All patients received the same basic treatment: intravenous fluid therapy for hydration, a single-oral-dose of azithromycin and intravenous antibiotic therapy for 7 days, vaginal micronized progesterone and indomethacin administrated orally. RESULTS: Mean gestational age at diagnosis was 22.5 weeks with an extension of pregnancy between 2.1 and 16 weeks, with eight patients (72.72%) who extended their pregnancy for more than 8 weeks. In all cases, live fetuses were obtained, with favorable evolution. CONCLUSIONS: Despite our limited experience, resulting from the low number of cases presenting, our results encourage us to propose conservative management in pregnancies complicated with a dilated cervix and membranes protruding into the vagina, as a reasonable alternative to surgical emergency cervical cerclage, which is currently considered the therapy of choice when extreme cervical shortening occurs in the second trimester of pregnancy.
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Cerclagem Cervical , Incompetência do Colo do Útero , Tratamento Conservador , Dilatação , Feminino , Humanos , Lactente , Primeira Fase do Trabalho de Parto , Gravidez , Incompetência do Colo do Útero/cirurgiaRESUMO
The sanitary status of grapevines has not yet been considered sufficiently in vineyards throughout Bosnia and Herzegovina (BiH). An extensive survey of five major grapevine viruses in the country was carried out in 2019. A total of 630 samples from the two dominant autochthonous cultivars, named Zilavka and Blatina, were tested by DAS-ELISA for the presence of grapevine leafroll-associated viruses (GLRaV-1 and 3), grapevine fleck virus (GFkV), grapevine fanleaf virus (GFLV) and Arabis mosaic virus (ArMV). Eighty-eight % of the samples were positive for at least one virus, and all five viruses were detected, thought with different incidence, i.e. GLRaV-3 (84%), GFLV (43%), GLRaV-1 (14%), GFkV (10%) and ArMV (0.2%). The majority of infected plants (about 75%) were asymptomatic. Specific virus symptoms were observed in the remaining infected plants, together with the reported GLRaV vectors, Planococcus ficus and Parthenolecanium corni, while nematodes of the Xiphinema genus were not found in the GFLV- or ArMV-infected vineyards. The GLRaV-3 CP phylogenetic analyses showed 75-100% nucleotide identity between the BiH and reference isolates, and the BiH isolates clustered into the major group. The dNS/dS ratio indicated a negative selection of the virus population, and the lack of geographical structuring within the population was observed. In addition, putative GLRaV-3 recombinants with breakpoints in the 5' of the CP gene were detected, while no recombinant strains were identified for the other four viruses. The obtained results indicate a deteriorated sanitary status of the cultivated grapevines, the prevalence and intraspecies genetic diversity of GLRaV-3 throughout the country. The establishment of certified grapevine material and adequate virus vector control is therefore of primary importance to prevent further spread of these viruses. This study presents the results of the first molecular characterisation of grapevine viruses in Bosnia and Herzegovina.
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Doenças das Plantas/virologia , Vírus de Plantas/isolamento & purificação , Vitis/virologia , Bósnia e Herzegóvina , Filogenia , RNA Viral/genéticaRESUMO
Tomato brown rugose fruit virus (ToBRFV) is a highly infectious virus, that is becoming a threat to tomato production worldwide. In this work we evaluated the localization of ToBRFV particles in tomato seeds, its seed transmission rate and efficacy of disinfection, and the effects of different thermal- and chemical-based treatments on ToBRFV-infected seeds' germination. Analyses demonstrated that ToBRFV was located in the seed coat, sometime in the endosperm, but never in the embryo; its transmission from infected seeds to plantlets occurs by micro-lesions during the germination. The ToBRFV seed transmission rate was 2.8% in cotyledons and 1.8% in the third true leaf. Regarding the different disinfection treatments, they returned 100% of germination at 14 days post-treatment (dpt), except for the treatment with 2% hydrochloric acid +1.5% sodium hypochlorite for 24 h, for which no seed germinated after 14 dpt. All treatments have the ability to inactivate ToBRFV, but in six out of seven treatments ToBRFV was still detectable by RT-qPCR. These results raise many questions about the correct way to carry out diagnosis at customs. To our knowledge, this is the first study on the effective localization of ToBRFV particles in seeds.
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In the last decades, the evolution of molecular diagnosis methods has generated different advanced tools, like loop-mediated isothermal amplification (LAMP). Currently, it is a well-established technique, applied in different fields, such as the medicine, agriculture, and food industries, owing to its simplicity, specificity, rapidity, and low-cost efforts. LAMP is a nucleic acid amplification under isothermal conditions, which is highly compatible with point-of-care (POC) analysis and has the potential to improve the diagnosis in plant protection. The great advantages of LAMP have led to several upgrades in order to implement the technique. In this review, the authors provide an overview reporting in detail the different LAMP steps, focusing on designing and main characteristics of the primer set, different methods of result visualization, evolution and different application fields, reporting in detail LAMP application in plant virology, and the main advantages of the use of this technique.
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BACKGROUND: Tomato brown rugose fruit virus (ToBRFV) is a highly infectious tobamovirus that causes severe disease in tomato (Solanum lycopersicum L.) crops. In Italy, the first ToBRFV outbreak occurred in 2018 in several provinces of the Sicily region. ToBRFV outbreak represents a serious threat for tomato crops in Italy and the Mediterranean Basin. METHODS: Molecular and biological characterisation of the Sicilian ToBRFV ToB-SIC01/19 isolate was performed, and a sensitive and specific Real-time RT-PCR TaqMan minor groove binder probe method was developed to detect ToBRFV in infected plants and seeds. Moreover, four different sample preparation procedures (immunocapture, total RNA extraction, direct crude extract and leaf-disk crude extract) were evaluated. RESULTS: The Sicilian isolate ToB-SIC01/19 (6,391 nt) showed a strong sequence identity with the isolates TBRFV-P12-3H and TBRFV-P12-3G from Germany, Tom1-Jo from Jordan and TBRFV-IL from Israel. The ToB-SIC01/19 isolate was successfully transmitted by mechanical inoculations in S. lycopersicum L. and Capsicum annuum L., but no transmission occurred in S. melongena L. The developed real-time RT-PCR, based on the use of a primer set designed on conserved sequences in the open reading frames3, enabled a reliable quantitative detection. This method allowed clear discrimination of ToBRFV from other viruses belonging to the genus Tobamovirus, minimising false-negative results. Using immunocapture and total RNA extraction procedures, the real-time RT-PCR and end-point RT-PCR gave the same comparable results. Using direct crude extracts and leaf-disk crude extracts, the end-point RT-PCR was unable to provide a reliable result. This developed highly specific and sensitive real-time RT-PCR assay will be a particularly valuable tool for early ToBRFV diagnosis, optimising procedures in terms of costs and time.
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In the present investigation, fresh and dried tomato samples from markets and packinghouses located in Apulia region (southern Italy) were analysed for Alternaria toxins. All samples proved to be contaminated by tenuazonic acid (TeA); in particular, dried tomatoes were contaminated in the range 425-81,592 µg/kg, while fresh tomatoes were in the range 11-4560 µg/kg. The second most abundant toxin was alternariol monomethyl ether (AME), followed by tentoxin (TEN) and alternariol (AOH). Overall dried tomatoes were more contaminated than fresh ones, although this seemed not directly related to the presence of sodium chloride, utilized in the drying process. Five representative Alternaria isolates within those collected from samples proved to be one Alternaria arborescens (A215) and four Alternaria alternata. Within the latter species, one strain belonged to morphotype tenuissima (A216), and three to alternata (A214, A217 and A218). They were confirmed to produce TeA, AOH, and AME in vitro. This study demonstrates the possible risk for consumers' health related to the consumption of contaminated fresh and dried tomatoes, and thus the need for suitable control strategies.
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Alternaria/química , Contaminação de Alimentos/análise , Solanum lycopersicum/química , Toxinas Biológicas/análise , Alternaria/crescimento & desenvolvimento , ItáliaRESUMO
Tuftsin-PhosphorylCholine (TPC) is a novel bi-specific molecule which links tuftsin and phosphorylcholine. TPC has shown immunomodulatory activities in experimental mouse models of autoimmune diseases. We studied herein the effects of TPC ex vivo on both peripheral blood mononuclear cells (PBMCs) and temporal artery biopsies (TABs) obtained from patients with giant cell arteritis (GCA) and age-matched disease controls. GCA is an immune-mediated disease affecting large vessels. Levels of 18 cytokines in supernatants, PBMC viability, T helper (Th) cell differentiation of PBMCs and gene expression in TABs were analyzed. Treatment ex vivo with TPC decreased the production of IL-1ß, IL-2, IL-5, IL-6, IL-9, IL-12(p70), IL-13, IL-17A, IL-18, IL-21, IL-22, IL-23, IFNγ, TNFα, GM-CSF by CD3/CD28 activated PBMCs whereas it negligibly affected cell viability. It reduced Th1 and Th17 differentiation while did not impact Th22 differentiation in PBMCs stimulated by phorbol 12-myristate 13-acetate plus ionomycin. In inflamed TABs, treatment with TPC down-regulated the production of IL-1ß, IL-6, IL-13, IL-17A and CD68 gene expression. The effects of TPC were comparable to the effects of dexamethasone, included as the standard of care, with the exception of a greater reduction of IL-2, IL-18, IFNγ in CD3/CD28 activated PBMCs and CD68 gene in inflamed TABs. In conclusion our results warrant further investigations regarding TPC as an immunotherapeutic agent in GCA and potentially other autoimmune and inflammatory diseases.
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Anti-Inflamatórios/uso terapêutico , Dexametasona/uso terapêutico , Arterite de Células Gigantes/tratamento farmacológico , Imunoterapia/métodos , Fosforilcolina/análogos & derivados , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Tuftsina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Combinação de Medicamentos , Feminino , Humanos , Ativação Linfocitária , Masculino , Fosforilcolina/uso terapêuticoRESUMO
Cyclic lipopeptides (CLPs) are considered as some of the most important secondary metabolites in different plant-associated bacteria, thanks to their antimicrobial, cytotoxic, and surfactant properties. In this study, our aim was to investigate the role of the Quorum Sensing (QS) system, PcoI/PcoR, and the LuxR-type transcriptional regulator RfiA in CLP production in the phytopatogenic bacterium, Pseudomonas corrugata based on our previous work where we reported that the pcoR and rfiA mutants were devoid of the CLPs cormycin and corpeptin production. Due to the close genetic link between the QS system and the RfiA (rfiA is co-transcribed with pcoI), it was difficult to ascertain the specific regulatory role in the expression of target genes. A transcriptional approach was undertaken to identify the specific role of the PcoR and RfiA transcriptional regulators for the expression of genes involved in CLP production. The RNA-seq-based transcriptional analysis of the wild-type (WT) strain CFBP 5454 in comparison with GL2 (pcoR mutant) and GLRFIA (rfiA mutant) was performed in cultural conditions favoring CLP production. Differential gene expression revealed that 152 and 130 genes have significantly different levels of expression in the pcoR and rfiA mutants, respectively. Of these, the genes linked to the biosynthesis of CLPs and alginate were positively controlled by both PcoR and RfiA. Blast homology analysis showed that 19 genes in a large CLP biosynthetic cluster involved in the production of three antimicrobial peptides, which span approximately 3.5% of the genome, are strongly over-expressed in the WT strain. Thus, PcoR and RfiA function mainly as activators in the production of bioactive CLPs, in agreement with phenotype analysis of mutants. RNA-seq also revealed that almost all the genes in the structural/biosynthetic cluster of alginate exopolysaccharide (EPS) are under the control of the PcoR-RfiA regulon, as supported by the 10-fold reduction in total EPS yield isolated in both mutants in comparison to the parent strain. A total of 68 and 38 gene expressions was independently regulated by PcoR or RfiA proteins, respectively, but at low level. qPCR experiments suggest that growth medium and plant environment influence the expression of CLP and alginate genes.
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In July 2016, an aggressive syndrome of tomato yellow leaf curl disease was reported in Sicily in tomato plants carrying the Ty-1 resistance gene. A total of 34 samples were collected and analyzed. Twenty-seven out of the 34 samples analyzed appeared to contain only recombinant molecules. One full sequence was obtained after cloning. Alignments and plot similarity analysis showed that the genome of the recombinant, named TYLCV-IL[IT:Sic23:16], was mostly derived from tomato yellow leaf curl virus (TYLCV), with a small region of 132 nucleotides in the non-coding region between the stem-loop and the start of the V2 ORF replaced by 124 nucleotides derived from a virus of a different species, tomato yellow leaf curl Sardinia virus. All plants in which the new recombinant was detected belonged to resistant tomato cultivars.