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1.
iScience ; 26(8): 107300, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37554463

RESUMO

METTL3 is the major writer of N6-Methyladenosine (m6A) and has been associated with controversial roles in cancer. This is best illustrated in urothelial carcinoma of the bladder (UCB), where METTL3 was described to have both oncogenic and tumor-suppressive functions. Here, we reinvestigated the role of METTL3 in UCB. METTL3 knockout reduced the oncogenic phenotype and m6A levels of UCB cell lines. However, complete depletion of METTL3/m6A was not achieved due to selection of cells expressing alternative METTL3 isoforms. Systematic vulnerability and inhibitor response analyses suggested that uroepithelial cells depend on METTL3 for viability. Furthermore, expression and survival analyses of clinical data revealed a complex role for METTL3 in UCB, with decreased m6A mRNA levels in UCB tumors. Our results suggest that METTL3 expression may be a suitable diagnostic UCB biomarker, as the enzyme promotes UCB formation. However, the suitability of the enzyme as a therapeutic target should be evaluated carefully.

2.
Gels ; 9(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37504426

RESUMO

Silica aerogels are highly porous materials with exceptional thermal insulation performance. They become even more attractive if combined thermal and acoustic insulation is achieved. Silica aerogel composites reinforced with fibres are an ingenious way to surpass the fragility stemmed from the aerogel's intrinsic porosity, and textile fibres are good sound absorption materials. Reclaimed fibres are a relatively low-cost feedstock and were obtained in this work exclusively through mechanical processes from textile wastes, thus promoting the concept of circular economy, namely for cotton, polyester and wool fibres. These reclaimed fibres were used as reinforcement matrices for silica aerogel composites obtained from sol-gel transformation of tetraethyl orthosilicate and isobutyltriethoxysilane/or vinyltrimethoxysilane precursors and dried at ambient pressure after silylation. Silica aerogel composites reinforced with reclaimed cotton fibres had the best sound absorption coefficient (a peak value of 0.89), while the polyester-reinforced composite exhibited the lowest thermal conductivity (k = ~24 mW m-1 K-1, Hot Disk). The better combined results on thermal and acoustic insulation were achieved by the wool-reinforced composites. The thermal conductivity values were less than 27 mW m-1 K-1, and the sound absorption coefficient achieved a peak value of 0.85. Therefore, the aerogel composites developed here can be selected for thermal or/and acoustic barriers by choosing a suitable type of fibre. Their design and preparation protocol followed environmental-friendly and cost-effective approaches.

3.
J Opt Soc Am A Opt Image Sci Vis ; 40(4): C101-C107, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132975

RESUMO

The performance of communication systems based on free-space optical links depends on external factors such as weather conditions. Among many atmospheric factors, turbulence can be the greatest challenge to performance. The characterization of atmospheric turbulence usually involves expensive equipment known as a scintillometer. This work presents a low-cost experimental setup for measuring the refractive index structure constant over water, which results in a statistical model based on weather conditions. The turbulence variations with air and water temperature, relative humidity, pressure, dew point, and different watercourse widths are analyzed for the proposed scenario.

4.
Int J Surg Case Rep ; 99: 107715, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36261948

RESUMO

INTRODUCTION: The widespread use of imaging methods has led to an increased identification of asymptomatic Pancreatic Cystic Lymphangiomas (PCL), a rare entity for which available information is very limited. PRESENTATION OF CASE: We present the case of an asymptomatic 61-year-old male, submitted to elective enucleation of a pancreatic head PCL at our institution. After four years of follow-up the patient is doing well and has no clinical or imaging signs of recurrence. DISCUSSION: Though rare, PCL should be included in the differential diagnosis of pancreatic cystic neoplasms. All efforts should be made to ascertain a preoperative diagnosis, as expectant follow-up could be a reasonable approach in asymptomatic patients and/or poor surgical candidates. In the face of an uncertain diagnosis, complete surgical excision may be the treatment of choice. CONCLUSION: The medical community worldwide should be encouraged to report all cases of PCL, as to increment the overall knowledge about this lesion.

5.
PLoS Negl Trop Dis ; 16(6): e0010559, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35759510

RESUMO

Epigenetic mechanisms are responsible for a wide range of biological phenomena in insects, controlling embryonic development, growth, aging and nutrition. Despite this, the role of epigenetics in shaping insect-pathogen interactions has received little attention. Gene expression in eukaryotes is regulated by histone acetylation/deacetylation, an epigenetic process mediated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). In this study, we explored the role of the Aedes aegypti histone acetyltransferase CBP (AaCBP) after infection with Zika virus (ZIKV), focusing on the two main immune tissues, the midgut and fat body. We showed that the expression and activity of AaCBP could be positively modulated by blood meal and ZIKV infection. Nevertheless, Zika-infected mosquitoes that were silenced for AaCBP revealed a significant reduction in the acetylation of H3K27 (CBP target marker), followed by downmodulation of the expression of immune genes, higher titers of ZIKV and lower survival rates. Importantly, in Zika-infected mosquitoes that were treated with sodium butyrate, a histone deacetylase inhibitor, their capacity to fight virus infection was rescued. Our data point to a direct correlation among histone hyperacetylation by AaCBP, upregulation of antimicrobial peptide genes and increased survival of Zika-infected-A. aegypti.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Aedes/genética , Animais , Epigênese Genética , Histona Acetiltransferases/genética , Histonas/genética , Mosquitos Vetores , Zika virus/fisiologia
6.
Sensors (Basel) ; 22(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35591113

RESUMO

Machine end-effector kinematic analysis is critical to optimizing transporting components where inertial forces are the main loads. While displacements may be measured with relatively high accuracy in transportation equipment motors, the inertial forces in the transported components are seldom optimized. This is especially relevant in electronic component placement systems, where the components have a wide range of configurations (i.e., geometry and mass) and the deployment dimensional/geometric tolerances are remarkably good. The optimization of these systems requires the monitoring of the real position of the accelerometers relative to the measurement point of interest with sufficient accuracy that allows the assembly position to be predicted instantaneously. This study shows a novel method to calibrate this equipment using triaxial accelerometers on a surface mount machine to measure the end-effector accelerations and velocities in its planar motion. The dynamic equations of the system and the method for integration are presented to address the uncertainty on the exact position of the accelerometer sensors relative to the measuring point of interest exist and allow the position correction to optimize response and accuracy.


Assuntos
Aceleração , Acelerometria , Fenômenos Biomecânicos , Movimento (Física)
7.
Hematol Rep ; 14(2): 143-148, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35466185

RESUMO

Myeloid sarcomas (MS) are rare extramedullary (EM) hematological tumors that generally arise during the natural course of acute myeloid leukemia (AML), occurring concomitantly with the onset of systemic leukemia; it can also occur following onset but rarely before. Common sites of EM involvement include the lymph nodes, skin, soft tissue, bone and peritoneum. Herein, we report the case of a 63-year-old man who presented EM AML upon initial diagnosis involving the bone marrow, lymph nodes and skin (leukemia cutis). A diagnosis was made based on immunohistochemistry (IHC). This case presents a diagnostic dilemma due to its atypical presentation and the sites involved. It also highlights the importance of IHC in the diagnosis of EM AML. The potential role of hypomethylating agents and Venetoclax in cases not eligible for hematopoietic stem cell transplant are also discussed.

8.
Front Cell Dev Biol ; 9: 794506, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957121

RESUMO

DNA methylation is an important epigenetic modification that has been repeatedly implied in organismal adaptation. However, many previous studies that have linked DNA methylation patterns to environmental parameters have been limited by confounding factors, such as cell-type heterogeneity and genetic variation. In this study, we analyzed DNA methylation variation in marbled crayfish, a clonal and invasive freshwater crayfish that is characterized by a largely tissue-invariant methylome and negligible genetic variation. Using a capture-based subgenome bisulfite sequencing approach that covers a small, variably methylated portion of the marbled crayfish genome, we identified specific and highly localized DNA methylation signatures for specimens from geographically and ecologically distinct wild populations. These results were replicated both biologically and technically by re-sampling at different time points and by using independent methodology. Finally, we show specific methylation signatures for laboratory animals and for laboratory animals that were reared at a lower temperature. Our results thus demonstrate the existence of context-dependent DNA methylation signatures in a clonal animal.

9.
J Surg Case Rep ; 2021(3): rjab087, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815758

RESUMO

Gastric lipomas are rare, representing 2-3% of all benign tumours of the stomach. Most of these stomach neoplasms are small and detected incidentally during endoscopic or radiology evaluations. Computed tomography is highly specific imaging for lipoma diagnosis. Endoscopy and endoscopic ultrasound are other important diagnostic modalities to confirm the diagnosis. Identifying typical features can avoid biopsy or surgery in asymptomatic patients. In patients with larger lesions, usually more than 2 cm, clinical presentation may encompass haemorrhage, abdominal pain, pyloric obstruction and dyspepsia. As a result of its extreme low incidence, treatment is not standardized, though it is widely accepted that a symptomatic tumour mandates resection. Here, we present the case of a 60-year-old female presenting with abdominal pain and recurrent vomiting due to a giant gastric lipoma (80 × 35 × 35 mm). The patient underwent laparotomy and an enucleation was performed.

10.
J Surg Case Rep ; 2020(12): rjaa490, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33343867

RESUMO

It is universally known and accepted that the development of a certain type of tissue outside its usual location, like in the gastrointestinal tract, can occur. This is a relatively common situation in the upper region of the gastrointestinal tract. However, the development of gastric mucosa in the gallbladder is a rare find. The following is the case of a 22-year-old male with an 18 mm gallbladder polyp, who electively underwent a laparoscopic cholecystectomy, having been diagnosed at a histopathological level with heterotopic gastric mucosa in the gallbladder. This brief article also aims to provide a reflection on the possible evolution of neoplasms from this histological change, based on the doubts raised in literature.

11.
J Surg Case Rep ; 2020(10): rjaa421, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33154810

RESUMO

Gastric schwannoma is an extremely rare mesenchymal tumour, representing only 0.2% of all gastric tumours. Obesity is an alarming worldwide disease whose only effective and sustained treatment seems to be surgical. We present a case of a 73-year-old female with epigastric pain and unspecific dyspeptic symptoms, whose diagnostic endoscopic procedures raised suspicion of a gastrointestinal stromal tumour. Given her good performance status, and since grade 2 obesity with high-risk comorbid conditions was present, she was considered a suitable candidate for laparoscopic sleeve gastrectomy. Both surgery and immediate postoperative period were uneventful. Histological and immunocytochemical analysis classified the tumour as benign gastric schwannoma. After 24 months, besides being disease-free, she presented an excess weight loss of 90.2%, with improvements in metabolic profile allowing withdrawal from chronic medication. The patient is healthier, satisfied and living an active life, showing that age by itself should not be a deterrent to bariatric surgery.

12.
PLoS Negl Trop Dis ; 14(7): e0008332, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32609727

RESUMO

Treatment and control of schistosomiasis still rely on only one effective drug, praziquantel (PZQ) and, due to mass treatment, the increasing risk of selecting for schistosome strains that are resistant to PZQ has alerted investigators to the urgent need to develop novel therapeutic strategies. The histone-modifying enzymes (HMEs) represent promising targets for the development of epigenetic drugs against Schistosoma mansoni. In the present study, we targeted the S. mansoni lysine-specific demethylase 1 (SmLSD1), a transcriptional corepressor, using a novel and selective synthetic inhibitor, MC3935, which was used to treat schistosomula and adult worms in vitro. By using cell viability assays and optical and electron microscopy, we showed that treatment with MC3935 affected parasite motility, egg-laying, tegument, and cellular organelle structures, culminating in the death of schistosomula and adult worms. In silico molecular modeling and docking analysis suggested that MC3935 binds to the catalytic pocket of SmLSD1. Western blot analysis revealed that MC3935 inhibited SmLSD1 demethylation activity of H3K4me1/2. Knockdown of SmLSD1 by RNAi recapitulated MC3935 phenotypes in adult worms. RNA-Seq analysis of MC3935-treated parasites revealed significant differences in gene expression related to critical biological processes. Collectively, our findings show that SmLSD1 is a promising drug target for the treatment of schistosomiasis and strongly support the further development and in vivo testing of selective schistosome LSD1 inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Desmetilases/antagonistas & inibidores , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/ultraestrutura , Esquistossomose mansoni/tratamento farmacológico , Animais , Anti-Helmínticos/farmacologia , Resistência a Medicamentos , Microscopia Eletrônica de Varredura , Oviposição/efeitos dos fármacos , Praziquantel/farmacologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/patologia
13.
Integr Comp Biol ; 60(2): 267-274, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333755

RESUMO

Invasive species represent a serious ecological threat for many ecosystems worldwide and provide a unique opportunity to investigate rapid adaptation and evolution. Genetic variation allows populations of organisms to be both robust and adaptable to different environmental conditions over evolutionary timeframes. In contrast, invasive animals can rapidly adapt to new environments, with minimal genetic diversity. Thus, the extent to which environmental effects can trigger epigenetic responses is particularly interesting for understanding the role of epigenetics in rapid adaptation. In this review, we provide a brief overview of the different epigenetic mechanisms that control gene expression, and emphasize the importance of epigenetics for environmental adaptation. We also discuss recent publications that provide important examples for the role of epigenetic mechanisms in environmental adaptation. Furthermore, we present an overview of the current knowledge about epigenetic modulation as an adaptive strategy for invasive species. A particularly interesting example is provided by the marbled crayfish, a novel, monoclonal freshwater crayfish species that has colonized diverse habitats within a few years. Finally, we address important limitations of current approaches and highlight the potential importance of less well-known mechanisms for non-genetic organismal adaptation.


Assuntos
Adaptação Biológica/genética , Astacoidea/genética , Epigênese Genética , Espécies Introduzidas , Animais , Ecossistema
14.
Plos Negl Trop Dis, v. 14, n. 7, e0008332, jul. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3085

RESUMO

Treatment and control of schistosomiasis still rely on only one effective drug, praziquantel (PZQ) and, due to mass treatment, the increasing risk of selecting for schistosome strains that are resistant to PZQ has alerted investigators to the urgent need to develop novel therapeutic strategies. The histone-modifying enzymes (HMEs) represent promising targets for the development of epigenetic drugs against Schistosoma mansoni. In the present study, we targeted the S. mansoni lysine-specific demethylase 1 (SmLSD1), a transcriptional corepressor, using a novel and selective synthetic inhibitor, MC3935, which was used to treat schistosomula and adult worms in vitro. By using cell viability assays and optical and electron microscopy, we showed that treatment with MC3935 affected parasite motility, egg-laying, tegument, and cellular organelle structures, culminating in the death of schistosomula and adult worms. In silico molecular modeling and docking analysis suggested that MC3935 binds to the catalytic pocket of SmLSD1. Western blot analysis revealed that MC3935 inhibited SmLSD1 demethylation activity of H3K4me1/2. Knockdown of SmLSD1 by RNAi recapitulated MC3935 phenotypes in adult worms. RNA-Seq analysis of MC3935-treated parasites revealed significant differences in gene expression related to critical biological processes. Collectively, our findings show that SmLSD1 is a promising drug target for the treatment of schistosomiasis and strongly support the further development and in vivo testing of selective schistosome LSD1 inhibitors.

15.
BMJ Case Rep ; 12(9)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31488447

RESUMO

Primary retroperitoneal mucinous cystic neoplasms (PRMCN) with borderline malignancy are exceptionally rare tumours with lack of pathognomonic clinical and imaging-specific features. Here, we report a case of PRMCN with borderline malignancy in a 62-year-old woman who presented with abdominal pain. Imaging studies revealed a well-defined cystic mass on the right flank in close relation with the cecum and caecal appendix, without other findings suggestive of malignancy. A possible diagnosis of an ovarian epithelial tumour was ruled out intraoperatively. After surgical excision, microscopic examination allowed the final diagnosis. As there is no evidence of disease during follow-up, complete tumour resection without cystic rupture appears to be the best therapeutic option. Thus, although rare, this tumour should be considered when imaging findings suggest an ovarian mucinous neoplasm in women with normal ovaries. An international registry for rare tumours and longer follow-ups may contribute for more consistent approach for managing these patients.


Assuntos
Cistadenoma Mucinoso/patologia , Neoplasias Retroperitoneais/patologia , Carcinoma Epitelial do Ovário/diagnóstico , Cistadenoma Mucinoso/diagnóstico por imagem , Cistadenoma Mucinoso/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/cirurgia
16.
BMC Ecol ; 19(1): 8, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30727994

RESUMO

BACKGROUND: The marbled crayfish (Procambarus virginalis) is a monoclonal, parthenogenetically reproducing freshwater crayfish species that has formed multiple stable populations worldwide. Madagascar hosts a particularly large and rapidly expanding colony of marbled crayfish in a unique environment characterized by a very high degree of ecological diversity. RESULTS: Here we provide a detailed characterization of five marbled crayfish populations in Madagascar and their habitats. Our data show that the animals can tolerate a wide range of ecological parameters, consistent with their invasive potential. While we detected marbled crayfish in sympatry with endemic crayfish species, we found no evidence for the transmission of the crayfish plague pathogen, a potentially devastating oomycete. Furthermore, our results also suggest that marbled crayfish are active predators of the freshwater snails that function as intermediate hosts for human schistosomiasis. Finally, we document fishing, farming and market sales of marbled crayfish in Madagascar. CONCLUSIONS: Our results provide a paradigm for the complex network of factors that promotes the invasive spread of marbled crayfish. The commercial value of the animals is likely to result in further anthropogenic distribution.


Assuntos
Astacoidea/fisiologia , Espécies Introduzidas , Características de História de Vida , Animais , Ecossistema , Madagáscar
17.
PLoS Negl Trop Dis ; 12(10): e0006873, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30365505

RESUMO

BACKGROUND: The possibility of emergence of praziquantel-resistant Schistosoma parasites and the lack of other effective drugs demand the discovery of new schistosomicidal agents. In this context the study of compounds that target histone-modifying enzymes is extremely promising. Our aim was to investigate the effect of inhibition of EZH2, a histone methyltransferase that is involved in chromatin remodeling processes and gene expression control; we tested different developmental forms of Schistosoma mansoni using GKS343, a selective inhibitor of EZH2 in human cells. METHODOLOGY/PRINCIPAL FINDINGS: Adult male and female worms and schistosomula were treated with different concentrations of GSK343 for up to two days in vitro. Western blotting showed a decrease in the H3K27me3 histone mark in all three developmental forms. Motility, mortality, pairing and egg laying were employed as schistosomicidal parameters for adult worms. Schistosomula viability was evaluated with propidium iodide staining and ATP quantification. Adult worms showed decreased motility when exposed to GSK343. Also, an approximate 40% reduction of egg laying by GSK343-treated females was observed when compared with controls (0.1% DMSO). Scanning electron microscopy showed the formation of bulges and bubbles throughout the dorsal region of GSK343-treated adult worms. In schistosomula the body was extremely contracted with the presence of numerous folds, and growth was markedly slowed. RNA-seq was applied to identify the metabolic pathways affected by GSK343 sublethal doses. GSK343-treated adult worms showed significantly altered expression of genes related to transmembrane transport, cellular homeostasis and egg development. In females, genes related to DNA replication and noncoding RNA metabolism processes were downregulated. Schistosomula showed altered expression of genes related to cell adhesion and membrane synthesis pathways. CONCLUSIONS/SIGNIFICANCE: The results indicated that GSK343 presents in vitro activities against S. mansoni, and the characterization of EZH2 as a new potential molecular target establishes EZH2 inhibitors as part of a promising new group of compounds that could be used for the development of schistosomicidal agents.


Assuntos
Replicação do DNA/efeitos dos fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Oviposição/efeitos dos fármacos , Piridonas/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/fisiologia , Animais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Redes e Vias Metabólicas/efeitos dos fármacos , Microscopia Eletrônica de Varredura , RNA não Traduzido/metabolismo , Schistosoma mansoni/enzimologia , Schistosoma mansoni/ultraestrutura , Análise de Sobrevida
18.
Epigenetics Chromatin ; 11(1): 57, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30286795

RESUMO

BACKGROUND: The parthenogenetic marbled crayfish (Procambarus virginalis) is a novel species that has rapidly invaded and colonized various different habitats. Adaptation to different environments appears to be independent of the selection of genetic variants, but epigenetic programming of the marbled crayfish genome remains to be understood. RESULTS: Here, we provide a comprehensive analysis of DNA methylation in marbled crayfish. Whole-genome bisulfite sequencing of multiple replicates and different tissues revealed a methylation pattern that is characterized by gene body methylation of housekeeping genes. Interestingly, this pattern was largely tissue invariant, suggesting a function that is unrelated to cell fate specification. Indeed, integrative analysis of DNA methylation, chromatin accessibility and mRNA expression patterns revealed that gene body methylation correlated with limited chromatin accessibility and stable gene expression, while low-methylated genes often resided in chromatin with higher accessibility and showed increased expression variation. Interestingly, marbled crayfish also showed reduced gene body methylation and higher gene expression variability when compared with their noninvasive mother species, Procambarus fallax. CONCLUSIONS: Our results provide novel insights into invertebrate gene body methylation and its potential role in adaptive gene regulation.


Assuntos
Astacoidea/genética , Metilação de DNA , Genes Essenciais , Animais , Montagem e Desmontagem da Cromatina , Genoma
19.
Front Immunol ; 9: 1979, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30258438

RESUMO

In chronic schistosomiasis, liver fibrosis is linked to portal hypertension, which is a condition associated with high mortality and morbidity. High mobility group box 1 (HMGB1) was originally described as a nuclear protein that functions as a structural co-factor in transcriptional regulation. However, HMGB1 can also be secreted into the extracellular milieu under appropriate signal stimulation. Extracellular HMGB1 acts as a multifunctional cytokine that contributes to infection, injury, inflammation, and immune responses by binding to specific cell-surface receptors. HMGB1 is involved in fibrotic diseases. From a clinical perspective, HMGB1 inhibition may represent a promising therapeutic approach for treating tissue fibrosis. In this study, we demonstrate elevated levels of HMGB1 in the sera in experimental mice or in patients with schistosomiasis. Using immunohistochemistry, we demonstrated that HMGB1 trafficking in the hepatocytes of mice suffering from acute schistosomiasis was inhibited by Glycyrrhizin, a well-known HMGB1 direct inhibitor, as well as by DIC, a novel and potential anti-HMGB1 compound. HMGB1 inhibition led to significant downregulation of IL-6, IL4, IL-5, IL-13, IL-17A, which are involved in the exacerbation of the immune response and liver fibrogenesis. Importantly, infected mice that were treated with DIC or GZR to inhibit HMGB1 pro-inflammatory activity showed a significant increase in survival and a reduction of over 50% in the area of liver fibrosis. Taken together, our findings indicate that HMGB1 is a key mediator of schistosomotic granuloma formation and liver fibrosis and may represent an outstanding target for the treatment of schistosomiasis.


Assuntos
Granuloma , Proteína HMGB1/imunologia , Cirrose Hepática , Fígado , Schistosoma mansoni/imunologia , Esquistossomose mansoni , Animais , Citocinas/imunologia , Feminino , Granuloma/imunologia , Granuloma/parasitologia , Granuloma/patologia , Humanos , Fígado/imunologia , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/imunologia , Cirrose Hepática/parasitologia , Cirrose Hepática/patologia , Masculino , Camundongos Endogâmicos BALB C , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/patologia
20.
Gene ; 671: 152-160, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859286

RESUMO

High-mobility group B (HMGB) proteins have highly conserved, unique DNA-binding domains, HMG boxes, that can bind non-B-type DNA structures, such as bent, kinked and unwound structures, with high affinity. HMGB proteins also promote DNA bending, looping and unwinding. In this study, we determined the role of the Aedes aegypti single HMG-box domain protein AaHMGB; characterized its structure, spatiotemporal expression levels, subcellular localization, and nucleic acid binding activities; and compared these properties with those of its double-HMG-box counterpart protein, AaHMGB1. Via qRT-PCR, we showed that AaHMGB is expressed at much higher levels than AaHMGB1 throughout mosquito development. In situ hybridization results suggested a role for AaHMGB and AaHMGB1 during embryogenesis. Immunolocalization in the midgut revealed that AaHMGB is exclusively nuclear. Circular dichroism and fluorescence spectroscopy analyses showed that AaHMGB exhibits common features of α-helical structures and is more stably folded than AaHMGB1, likely due to the presence of one or two HMG boxes. Using several DNA substrates or single-stranded RNAs as probes, we observed significant differences between AaHMGB and AaHMGB1 in terms of their binding patterns, activity and/or specificity. Importantly, we showed that the phosphorylation of AaHMGB plays a critical role in its DNA-binding activity. Our study provides additional insight into the roles of single- versus double-HMG-box-containing proteins in nucleic acid interactions for better understanding of mosquito development, physiology and homeostasis.


Assuntos
Aedes/crescimento & desenvolvimento , Proteínas HMGB/química , Proteínas HMGB/genética , Proteínas HMGB/metabolismo , Aedes/genética , Aedes/metabolismo , Animais , Núcleo Celular/metabolismo , Dicroísmo Circular , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Modelos Moleculares , Fosforilação , Estrutura Secundária de Proteína , Distribuição Tecidual
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