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1.
Medicine (Baltimore) ; 102(14): e33435, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37026914

RESUMO

RATIONALE: Meningeal melanocytoma is a rare benign pigmented tumor originat from leptomeningeal melanocytes. Here, we report the case of a female who presented with numbness and weakness of the limbs for approximately 6 months. PATIENT CONCERNS: We report the case of a 60-year-old Chinese female who presented with numbness and weakness of the limbs for approximately 6 months. computed tomography (CT) and magnetic resonance imaging (MRI) revealed a dumbbell-shaped tumor inside and outside the cervical (C) spinal canal. DIAGNOSES: The patient was using CT and MRI. Subsequently, the patient underwent surgery, and low-grade melanocytoma was diagnosed pathologically. INTERVENTIONS: Subsequently, the patient underwent a surgery, and the tumor was completely removed. OUTCOMES: The tumor did not recur after 6 months. CONCLUSION: This case suggested 2 "take-away" lessons: first, spinal meningeal melanocytomas may be dumbbell-shaped; and second, melanocytoma could appear as hyperintense, isointense, or hypointense on T2-weighted MRI.


Assuntos
Melanoma , Neoplasias Meníngeas , Nevo Pigmentado , Neoplasias da Retina , Neoplasias Cutâneas , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Hipestesia , Recidiva Local de Neoplasia/patologia , Melanócitos/patologia , Nevo Pigmentado/patologia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias da Retina/patologia , Imageamento por Ressonância Magnética , Neoplasias Cutâneas/patologia
2.
Funct Plant Biol ; 48(9): 936-947, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34112313

RESUMO

Hypericum perforatum L. (St. John's wort) is a well-known medicinal plant that possesses secondary metabolites with beneficial pharmacological properties. However, improvement in the production of secondary metabolites via genetic manipulation is a challenging task as H. perforatum remains recalcitrant to Agrobacterium tumefaciens-mediated transformation. Here, the transcripts of key genes involved in several plant defence responses (secondary metabolites, RNA silencing, reactive oxygen species (ROS) and specific defence genes) were investigated in H. perforatum suspension cells inoculated with A. tumefaciens by quantitative real-time PCR. Results indicated that key genes from the xanthone, hypericin and melatonin biosynthesis pathways, the ROS-detoxification enzyme HpAOX, as well as the defence genes Hyp-1 and HpPGIP, were all upregulated to rapidly respond to A. tumefaciens elicitation in H. perforatum. By contrast, expression levels of genes involved in hyperforin and flavonoid biosynthesis pathways were markedly downregulated upon A. tumefaciens elicitation. In addition, we compared the expression patterns of key genes in H. perforatum leaf tissues with and without dark glands, a major site of secondary metabolite production. Overall, we provide evidence for the upregulation of several phenylpropanoid pathway genes in response to elicitation by Agrobacterium, suggesting that production of secondary metabolites could modulate H. perforatum recalcitrance to A. tumefaciens-mediated transformation.


Assuntos
Hypericum , Agrobacterium tumefaciens/genética , Expressão Gênica , Hypericum/genética , Óleos de Plantas
3.
J Plant Physiol ; 253: 153268, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32947246

RESUMO

Hypericum perforatum L is a remarkable source of high-value secondary metabolites with increasing applications in pharmaceutical industry. However, improvement in the production of secondary metabolites through genetic engineering is a demanding task, as H. perforatum is not amenable to Agrobacterium tumefaciens-mediated transformation. In this study, we identified a Polygalacturonase-inhibiting protein (PGIP) gene from a subtractive cDNA library of A. tumefaciens-treated H. perforatum suspension cells. The role of HpPGIP in defense against A. tumefaciens was analyzed in transgenic Nicotiana tabacum overexpressing HpPGIP alone or fused at the N-terminus to Phenolic oxidative coupling protein (Hyp-1), a gene that positively modulates resistance to A. tumefaciens. Furthermore, virus-induced gene silencing was employed to knock down the expression of the PGIP homologous in N. benthamiana. Results showed that Agrobacterium-mediated expression efficiency greatly decreased in both HpPGIP and Hyp-1-PGIP transgenic plants, as assessed by GUS staining assays. However, silencing of PGIP in N. benthamiana increased the resistance to A. tumefaciens rather than susceptibility, which correlated with induction of pathogenesis-related proteins (PRs). The expression of core genes involved in several defense pathways was also analyzed in transgenic tobacco plants. Overexpression of HpPGIP led to up-regulation of key genes involved in hormone signaling, microRNA-based gene silencing, homeostasis of reactive oxygen species, and the phenylpropanoid pathway. Overexpression of Hyp-1-PGIP seemed to enhance the effect of PGIP on the expression of most genes analyzed. Moreover, HpPGIP was detected in the cytoplasm, nucleus and the plasma membrane or cell wall by confocal microscopy. Overall, our findings suggest HpPGIP modulates recalcitrance to A. tumefaciens-mediated transformation in H. perforatum.


Assuntos
Agrobacterium tumefaciens/fisiologia , Inibidores Enzimáticos/metabolismo , Hypericum/enzimologia , Nicotiana/enzimologia , Proteínas de Plantas/metabolismo , Expressão Gênica , Biblioteca Gênica , Inativação Gênica , Hypericum/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Nicotiana/genética , Nicotiana/microbiologia
4.
J Gen Virol ; 101(1): 122-135, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31730035

RESUMO

Plants are simultaneously exposed to a variety of biotic and abiotic stresses, such as infections by viruses and bacteria, or drought. This study aimed to improve our understanding of interactions between viral and bacterial pathogens and the environment in the incompatible host Nicotiana benthamiana and the susceptible host Arabidopsis thaliana, and the contribution of viral virulence proteins to these responses. Infection by the Potato virus X (PVX)/Plum pox virus (PPV) pathosystem induced resistance to Pseudomonas syringae (Pst) and to drought in both compatible and incompatible bacteria-host interactions, once a threshold level of defence responses was triggered by the virulence proteins P25 of PVX and the helper component proteinase of PPV. Virus-induced resistance to Pst was compromised in salicylic acid and jasmonic acid signalling-deficient Arabidopsis but not in N. benthamiana lines. Elevated temperature and CO2 levels, parameters associated with climate change, negatively affected resistance to Pst and to drought induced by virus infection, and this correlated with diminished H2O2 production, decreased expression of defence genes and a drop in virus titres. Thus, diminished virulence should be considered as a potential factor limiting the outcome of beneficial trade-offs in the response of virus-infected plants to drought or bacterial pathogens under a climate change scenario.


Assuntos
Dióxido de Carbono/metabolismo , Interações entre Hospedeiro e Microrganismos/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Pseudomonas syringae/fisiologia , Pseudomonas syringae/virologia , Arabidopsis/microbiologia , Arabidopsis/virologia , Ciclopentanos/metabolismo , Secas , Regulação da Expressão Gênica de Plantas/fisiologia , Peróxido de Hidrogênio/metabolismo , Oxilipinas/metabolismo , Ácido Salicílico/metabolismo , Temperatura , Virulência/fisiologia
5.
Planta ; 251(1): 13, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776675

RESUMO

MAIN CONCLUSION: Phenolic oxidative coupling protein (Hyp-1) isolated from Hypericum perforatum L. was characterized as a defense gene involved in H. perforatum recalcitrance to Agrobacterium tumefaciens-mediated transformation Hypericum perforatum L. is a reservoir of high-value secondary metabolites of increasing interest to researchers and to the pharmaceutical industry. However, improving their production via genetic manipulation is a challenging task, as H. perforatum is recalcitrant to Agrobacterium tumefaciens-mediated transformation. Here, phenolic oxidative coupling protein (Hyp-1), a pathogenesis-related (PR) class 10 family gene, was selected from a subtractive cDNA library from A. tumefaciens-treated H. perforatum suspension cells. The role of Hyp-1 in defense against A. tumefaciens was analyzed in transgenic Nicotiana tabacum and Lactuca sativa overexpressing Hyp-1, and in Catharanthus roseus silenced for its homologous Hyp-1 gene, CrIPR. Results showed that Agrobacterium-mediated expression efficiency greatly decreased in Hyp-1 transgenic plants. However, silencing of CrIPR induced CrPR-5 expression and decreased expression efficiency of Agrobacterium. The expression of core genes involved in several defense pathways was also analyzed in Hyp-1 transgenic tobacco plants. Overexpression of Hyp-1 led to an ample down-regulation of key genes involved in auxin signaling, microRNA-based gene silencing, detoxification of reactive oxygen species, phenylpropanoid pathway and PRs. Moreover, Hyp-1 was detected in the nucleus, plasma membrane and the cytoplasm of epidermal cells by confocal microscopy. Overall, our findings suggest Hyp-1 modulates recalcitrance to A. tumefaciens-mediated transformation in H. perforatum.


Assuntos
Agrobacterium tumefaciens/fisiologia , Catharanthus/metabolismo , Hypericum/metabolismo , Catharanthus/microbiologia , Hypericum/microbiologia , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , Nicotiana/metabolismo , Nicotiana/microbiologia
6.
J Int Med Res ; 45(6): 2110-2118, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28643533

RESUMO

Objective Acute organ embolism in children with Mycoplasma pneumoniae pneumonia (MPP) has been reported, but changes in coagulation are unclear. This study aimed to investigate changes in coagulation in children with MPP. Methods A total of 185 children with MMP (cases) and 117 healthy children (controls) were recruited. We measured prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and plasma fibrinogen (FIB) and D-dimer levels. Results Plasma FIB (3.39 ± 0.96 g/L vs 2.93 ± 0.6 6g/L, t = 4.50) and D-dimer (326.45 ± 95.62mg/L vs 263.93 ± 103.32mg/L, t=5.36) in MPP children were higher than controls and PT (9.54 ± 4.97S vs 11.48 ± 5.96S, t=3.05) and APTT (31.41 ± 12.01S vs 38.38 ± 11.72S, t=4.95) were shorter than controls. FIB, D-dimer, PT, and APTT were not different between the high IgM-titre and low-titre groups. The areas under the receiver operating characteristic curves in cases and controls for plasma FIB and D-dimer levels were 0.654 (95% confidence interval [CI], 0.593-0.716, P = 0.031) and 0.682 (95% CI, 0.619-0.744, P = 0.032), respectively. Conclusions Children with MPP have a higher risk of blood coagulation and thrombosis. Controlling these problems should be considered as soon as possible.


Assuntos
Coagulação Sanguínea , Mycoplasma pneumoniae/fisiologia , Pneumonia por Mycoplasma/sangue , Pneumonia por Mycoplasma/microbiologia , Estudos de Casos e Controles , Criança , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinogênio/metabolismo , Humanos , Masculino , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Curva ROC
7.
Oncol Lett ; 13(5): 2965-2970, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28521402

RESUMO

In order to provide an effective way to prevent or substantially delay the recurrence of invasive meningioma, and improve the curative effect of surgical treatment, we collected and analyzed the clinical manifestations, pathological features, preoperative imaging characteristics as well the data obtained during the surgical treatment of invasive meningioma. From February 2014 to February 2016, 59 patients with invasive meningioma were enrolled in this study. Invasive meningioma was confirmed in all patients by operation. Information about clinical manifestations, pathological features, preoperative imaging and surgical treatment were collected and analyzed. After surgery, pathological specimens were collected, and cases were confirmed as invasive meningioma by pathological examination. The course of disease ranged from 15 days to 7 years (average, 13.2 months). We used World Health Organization (WHO) criteria for classification of meningioma in the nervous system tumors as our reference. Symptoms were as follows: Intracranial hypertension (29 cases), cranial nerve dysfunction (10 cases), epilepsy (11 cases) and other symptoms (9 cases). We had 56 cases of WHO grade I; 6 cases of WHO grade II and 7 cases of WHO grade III. Surgical removal was: Simpson grade I (56 cases), Simpson grade II (2 cases), Simpson grade III and above (56 cases). We used before surgery imaging data to formulate our surgical plan. In general, during surgeries we did not proceed to complete resection, because in the majority of cases, some key structures were invaded and meningioma was very deep and any attempt for total resection could easily lead to significant damage to these structures.

8.
Front Plant Sci ; 7: 879, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446112

RESUMO

Hypericum perforatum (St John's wort) is a reservoir of diverse classes of biologically active and high value secondary metabolites, which captured the interest of both researchers and the pharmaceutical industry alike. Several studies and clinical trials have shown that H. perforatum extracts possess an astounding array of pharmacological properties. These properties include antidepressant, anti-inflammatory, antiviral, anti-cancer, and antibacterial activities; and are largely attributed to the naphtodianthrones and xanthones found in the genus. Hence, improving their production via genetic manipulation is an important strategy. In spite of the presence of contemporary genome editing tools, genetic improvement of this genus remains challenging without robust transformation methods in place. In the recent past, we found that H. perforatum remains recalcitrant to Agrobacterium tumefaciens mediated transformation partly due to the induction of plant defense responses coming into play. However, H. perforatum transformation is possible via a non-biological method, biolistic bombardment. Some research groups have observed the induction of hairy roots in H. perforatum after Agrobacterium rhizogenes co-cultivation. In this review, we aim at updating the available methods for regeneration and transformation of H. perforatum. In addition, we also propose a brief perspective on certain novel strategies to improve transformation efficiency in order to meet the demands of the pharmaceutical industry via metabolic engineering.

9.
Methods Mol Biol ; 1391: 317-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27108327

RESUMO

Hypericin, an important determinant of the pharmacological properties of the genus Hypericum, is considered as a major molecule for drug development. However, biosynthesis and accumulation of hypericin is not well understood. Identification of genes differentially expressed in tissues with and without hypericin accumulation is a useful strategy to elucidate the mechanisms underlying the development of the dark glands and hypericin biosynthesis. Suppression Subtractive Hybridization (SSH) is a unique method for PCR-based amplification of specific cDNA fragments that differ between a control (driver) and experimental (tester) transcriptome. This technique relies on the removal of dsDNA formed by hybridization between a control and test sample, thus eliminating cDNAs of similar abundance, and retaining differentially expressed or variable in sequence cDNAs. In our laboratory we applied this method to identify the genes involved in the development of dark glands and accumulation of hypericin in Hypericum perforatum. Here we describe the complete procedure for the construction of hypericin gland-specific subtracted cDNA library.


Assuntos
Biblioteca Gênica , Hypericum/genética , Hypericum/metabolismo , Perileno/análogos & derivados , Técnicas de Hibridização Subtrativa/métodos , Antracenos , Vias Biossintéticas , DNA Complementar/genética , Germinação , Hypericum/anatomia & histologia , Hypericum/crescimento & desenvolvimento , Perileno/análise , Perileno/metabolismo , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , RNA de Plantas/genética
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(5): 504-7, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24857001

RESUMO

OBJECTIVE: To study the prognostic significance of coagulation disorders in children with hemophagocytic syndrome (HPS). METHODS: Thirty-five children with HPS were retrospectively studied to analyze the etiology, clinical characteristics, laboratory results and treatment outcomes. RESULTS: After treatment, 27 of the 35 HPS patients survived, and the other 8 cases died. All cases were treated according to the HLH-2004 protocol, but etoposide (VP-16) was not used in 10 of them. The response rate in patients who received VP-16 (22/25, 88%) was significantly higher than that in those not receiving VP-16 (5/10, 50%) (P<0.05). Compared with the survival group, the dead group had significantly lower platelet count, fibrinogen level, and VP-16 utilization rate (P<0.05) but significantly longer activated partial thromboplastin time and prothrombin time (P<0.05). CONCLUSIONS: Coagulation function can be used as an indicator of disease outcome. It is essential for improving the clinical outcome of HPS to monitor the coagulation function during treatment, detect and correct abnormalities in time, and provide treatment strictly according to the HLH-2004 protocol.


Assuntos
Coagulação Intravascular Disseminada/mortalidade , Linfo-Histiocitose Hemofagocítica/mortalidade , Adolescente , Criança , Pré-Escolar , Etoposídeo/uso terapêutico , Feminino , Humanos , Lactente , Linfo-Histiocitose Hemofagocítica/sangue , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Masculino , Prognóstico , Estudos Retrospectivos
11.
Plant Cell ; 24(1): 259-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22247253

RESUMO

Unique among the known plant and animal viral suppressors of RNA silencing, the 2b protein interacts directly with both small interfering RNA (siRNA) and ARGONAUTE1 (AGO1) and AGO4 proteins and is targeted to the nucleolus. However, it is largely unknown which regions of the 111-residue 2b protein determine these biochemical properties and how they contribute to its diverse silencing suppressor activities. Here, we identified a functional nucleolar localization signal encoded within the 61-amino acid N-terminal double-stranded RNA (dsRNA) binding domain (dsRBD) that exhibited high affinity for short and long dsRNA. However, physical interaction of 2b with AGOs required an essential 33-residue region C-terminal to the dsRBD and was sufficient to inhibit the in vitro AGO1 Slicer activity independently of its dsRNA binding activities. Furthermore, the direct 2b-AGO interaction was not essential for the 2b suppression of posttranscriptional gene silencing (PTGS) and RNA-directed DNA methylation (RdDM) in vivo. Lastly, we found that the 2b-AGO interactions in vivo also required the nucleolar targeting of 2b and had the potential to redistribute both the 2b and AGO proteins in nucleus. These findings together suggest that 2b may suppress PTGS and RdDM in vivo by binding and sequestering siRNA and the long dsRNA precursor in a process that is facilitated by its interactions with AGOs in the nucleolus.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Argonautas/metabolismo , Metilação de DNA/genética , Proteínas Virais/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Argonautas/genética , Dados de Sequência Molecular , Interferência de RNA/fisiologia , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno , Proteínas Virais/genética
12.
J Virol ; 85(24): 13384-97, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21994448

RESUMO

RNA silencing provides protection against RNA viruses by targeting both the helper virus and its satellite RNA (satRNA). Virus-derived small interfering RNAs (vsiRNAs) bound with Argonaute (AGO) proteins are presumed participants in the silencing process. Here, we show that a vsiRNA targeted to virus RNAs triggers the host RNA-dependent RNA polymerase 6 (RDR6)-mediated degradation of viral RNAs. We confirmed that satRNA-derived small interfering RNAs (satsiRNAs) could be associated with different AGO proteins in planta. The most frequently cloned satsiRNA, satsiR-12, was predicted to imperfectly match to Cucumber mosaic virus (CMV) RNAs in the upstream area of the 3' untranslated region (3' UTR). Moreover, an artificial satsiR-12 (asatsiR-12) mediated cleavage of a green fluorescent protein (GFP) sensor construct harboring the satsiR-12 target site. asatsiR-12 also mediated reduction of viral RNAs in 2b-deficient CMV (CMVΔ2b)-infected Nicotiana benthamiana. The reduction was not observed in CMVΔ2b-infected RDR6i plants, in which RDR6 was silenced. Following infection with 2b-containing CMV, the reduction in viral RNAs was not observed in plants of either genotype, indicating that the asatsiR-12-mediated reduction of viral RNAs in the presence of RDR6 was inhibited by the 2b protein. Our results suggest that satsiR-12 targeting the 3' UTR of CMV RNAs triggered RDR6-dependent antiviral silencing. Competition experiments with wild-type CMV RNAs and anti-satsiR-12 mutant RNA1 in the presence of 2b and satRNA demonstrate the inhibitory effect of the 2b protein on the satsiR-12-related degradation of CMV RNAs, revealing a substantial suppressor function of the 2b protein in native CMV infection. Our data provide evidence for the important biological functions of satsiRNAs in homeostatic interactions among the host, virus, and satRNA in the final outcome of viral infection.


Assuntos
Regiões 3' não Traduzidas , Cucumovirus/genética , Cucumovirus/imunologia , RNA Satélite/genética , RNA Interferente Pequeno/genética , RNA Viral/metabolismo , Estabilidade de RNA , RNA Satélite/metabolismo , RNA Interferente Pequeno/metabolismo , Nicotiana/virologia
13.
Mol Plant Pathol ; 12(6): 595-605, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21722297

RESUMO

Satellite RNAs (satRNAs) depend on cognate helper viruses for replication, encapsidation, movement and transmission. Many satRNAs with different symptom modulation effects have been reported. The pathogenicity of satRNAs is thought to be the result of a direct interaction among the satRNA, helper viruses and host factors by unknown mechanisms. To understand the effect of satRNA of Cucumber mosaic virus (a severe field ShanDong strain, SD-CMV) on pathogenicity, and the possible involvement of host RNA silencing pathways in pathogenicity, we constructed biologically active CMV cDNA clones and a CMV-Δ2b mutant lacking the open reading frame of 2b, a silencing suppressor protein, in order to infect Nicotiana benthamiana and Arabidopsis with or without SD-satRNA. We found that SD-satRNA reduced the accumulation of the 2b protein and its coding RNA4A and attenuated the yellowing caused by SD-CMV infection. Small RNA analysis indicated that the 2b protein interfered with RNA silencing, specifically in the synthesis of CMV RNA3-derived small interfering RNAs (R3-siRNAs). The accumulation of R3-siRNAs in CMV-Δ2b infection was reduced in the presence of satRNA, for which greater accumulation of satRNA-derived siRNAs (satsiRNAs) was detected. Our results suggest that abundant SD-satRNA serving as target for RNA silencing may play a role in protecting helper CMV RNA, especially, subgenomic RNA4, from being targeted by RNA silencing. This compensates for the increase in RNA silencing resulting from the reduction in expression of the 2b suppressor in the presence of satRNA. Our data provide evidence that a plant silencing mechanism is involved in the pathogenicity of satRNA.


Assuntos
Cucumovirus/fisiologia , Genes Supressores , Doenças das Plantas/virologia , RNA Satélite/metabolismo , Proteínas Virais/metabolismo , Agrobacterium/fisiologia , Arabidopsis/virologia , Cucumovirus/genética , Cucumovirus/patogenicidade , DNA Complementar/genética , Genoma Viral/genética , RNA Interferente Pequeno/metabolismo , Nicotiana/virologia
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