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1.
Plant Physiol ; 189(3): 1741-1756, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35385078

RESUMO

Root-knot nematodes (RKNs) are among the most damaging pests of agricultural crops. Meloidogyne is an extremely polyphagous genus of nematodes that can infect thousands of plant species. A few genes for resistance (R-genes) to RKN suitable for use in crop breeding have been identified, but virulent strains and species of RKN have emerged that render these R-genes ineffective. Secretion of RKN effectors targeting plant functions mediates the reprogramming of root cells into specialized feeding cells, the giant cells, essential for RKN development and reproduction. Conserved targets among plant species define the more relevant strategies for controlling nematode infection. The EFFECTOR18 (EFF18) protein from M. incognita interacts with the spliceosomal small nuclear ribonucleoprotein D1 (SmD1) in Arabidopsis (Arabidopsis thaliana), disrupting its function in alternative splicing regulation and modulating the giant cell transcriptome. We show here that EFF18 is a conserved RKN-specific effector that targets this conserved spliceosomal SmD1 protein in Solanaceae. This interaction modulates alternative splicing events produced by tomato (Solanum lycopersicum) in response to M. incognita infection. The alteration of SmD1 expression by virus-induced gene silencing in Solanaceae affects giant cell formation and nematode development. Thus, our work defines a promising conserved SmD1 target gene to develop broad resistance for the control of Meloidogyne spp. in plants.


Assuntos
Arabidopsis , Solanum lycopersicum , Tylenchoidea , Animais , Arabidopsis/genética , Produtos Agrícolas , Interações Hospedeiro-Parasita/fisiologia , Solanum lycopersicum/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Tylenchoidea/fisiologia
2.
Adv Exp Med Biol ; 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37291444

RESUMO

INTRODUCTION: The pro-inflammatory cytokine interferon-gamma (IFN-γ) is reported to be an agent that boosts the immune modulation of mesenchymal stem cells (MSCs). However, the effects of IFN-γ on the chondrogenic potential of treated MSCs have not been evaluated in depth. This study aimed to evaluate the effects of IFN-γ on the immune modulation and chondrogenic potential of human umbilical cord-derived MSCs (hUC-MSCs). METHODS: UC-MSCs were isolated and expanded following published protocols. They were characterized as MSCs before their use in further experiments. The UC-MSCs were treated with IFN-γ at 10 ng/mL for 48 h. Changes in phenotype were investigated based on changes in MSC markers, immunomodulatory genes (TGF-ß, IL-4, and IDO) for immune modulation, and cartilage-related genes during the induction of differentiation (Col1a2, Col2a1, Sox9, Runx2, and Acan) for chondrogenic potential. RESULTS: IFN-γ-treated UC-MSCs maintained MSC markers and exhibited decreased expression of transcriptional regulatory factors in chondrogenesis (Sox9 and Runx2) and the extracellular matrix-specific genes Col1a2 and Acan but not Col2a1 compared to non-treated cells (p < 0.05). Furthermore, the immunomodulatory capability of IFN-γ-treated UC-MSCs was clearly revealed through their increased expression of IDO and IL-4 and decreased expression of TGF-ß compared to non-treated cells (p < 0.05). CONCLUSION: This study demonstrated that UC-MSCs treated with IFN-γ at 10 ng/mL had reduced expression of chondrocyte-specific genes; however, they maintained multi-lineage differentiation and exhibited immunomodulatory properties.

3.
Chem Biodivers ; 19(12): e202200520, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36380709

RESUMO

From a CH2 Cl2 -soluble fraction of the stem barks of Taxus wallichiana, one new abeo-icetexane-type diterpenoid, taxamairin I (1), was isolated. Its absolute configuration was elucidated based on spectroscopic interpretation and time-dependent density functional theory (TD-DFT) calculation of optical rotation. In addition, the plausible biosynthesis pathway for the formation of the new abeo-icetexane-type diterpenoid was proposed. Taxamairin I (1), at a concentration of 100 µM, did not show cytotoxicity against Hep3B human liver cancer cell lines.


Assuntos
Diterpenos , Taxus , Humanos , Linhagem Celular , Diterpenos/farmacologia , Diterpenos/metabolismo , Taxus/química
4.
New Phytol ; 229(6): 3408-3423, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33206370

RESUMO

The root-knot nematode Meloidogyne incognita secretes specific effectors (MiEFF) and induces the redifferentiation of plant root cells into enlarged multinucleate feeding 'giant cells' essential for nematode development. Immunolocalizations revealed the presence of the MiEFF18 protein in the salivary glands of M. incognita juveniles. In planta, MiEFF18 localizes to the nuclei of giant cells demonstrating its secretion during plant-nematode interactions. A yeast two-hybrid approach identified the nuclear ribonucleoprotein SmD1 as a MiEFF18 partner in tomato and Arabidopsis. SmD1 is an essential component of the spliceosome, a complex involved in pre-mRNA splicing and alternative splicing. RNA-seq analyses of Arabidopsis roots ectopically expressing MiEFF18 or partially impaired in SmD1 function (smd1b mutant) revealed the contribution of the effector and its target to alternative splicing and proteome diversity. The comparison with Arabidopsis galls data showed that MiEFF18 modifies the expression of genes important for giant cell ontogenesis, indicating that MiEFF18 modulates SmD1 functions to facilitate giant cell formation. Finally, Arabidopsis smd1b mutants exhibited less susceptibility to M. incognita infection, and the giant cells formed on these mutants displayed developmental defects, suggesting that SmD1 plays an important role in the formation of giant cells and is required for successful nematode infection.


Assuntos
Células Gigantes , Proteínas de Helminto , Doenças das Plantas/parasitologia , Proteínas de Plantas , Spliceossomos , Tylenchoidea , Animais , Arabidopsis , Interações Hospedeiro-Parasita , Solanum lycopersicum , Proteínas de Plantas/genética , Raízes de Plantas
5.
Adv Exp Med Biol ; 1084: 109-128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30242785

RESUMO

INTRODUCTION: Since the 1980s, adipose-derived stem cells (ASCs) have become a powerful and potential source for stem cell-based therapy, regenerative medicine, and even drug delivery in cancer treatment. The development of off-the-shelf mesenchymal stem cells (MSCs), including ASCs, has rapidly advanced in recent years with several clinical trials and approved products. In this technology, ASCs should be expanded long term in order to harvest higher cell number. In this study, senescence of ASCs after long-term expansion was evaluated. METHODS: Human ASCs (hASCs) were isolated and cultured continuously at a density of 103 cells/cm2 up to passage 15. The cells were assessed for aging via changes in the following: characteristics of MSCs, mitochondrial activity, accumulation of beta-galactosidase, and expression of tumor suppressor genes. RESULTS: The results showed that following in vitro expansion to the 15th passage, ASCs did not show changes in immunophenotype, except for decreased expression of CD105. However, the cells increased in size and in shape and complexity (toward the "fried egg" morphology). They also almost ceased to proliferate in passage 15. Nonetheless, they maintained in vitro differentiation potential toward osteoblasts, chondrocytes, and adipocytes. Expression of tumor suppressor genes p53 and p16 did not significantly change, while p27 was significantly downregulated. Mitochondrial activities also decreased slightly in culture from passage 5 to passage 10 and remained stable to passage 15. ASCs also showed increased accumulation of beta-galactosidase in culture, but it was negligible. CONCLUSION: In conclusion, hASCs exhibited some particular characteristics of aged stem cells when the number of subculture cells increased. However, up to passage 10, ASCs also retained almost all of the characteristics of MSCs.


Assuntos
Adipócitos , Tecido Adiposo , Senescência Celular , Células-Tronco Mesenquimais , Adipócitos/citologia , Tecido Adiposo/citologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco
6.
Adv Exp Med Biol ; 1083: 145-156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29423674

RESUMO

Mesenchymal stem cell (MSC) transplantation is a novel treatment for diabetes mellitus, especially type 1 diabetes. Many recent publications have demonstrated the efficacy of MSC transplantation on reducing blood glucose and increasing insulin production in both preclinical and clinical trials. However, the investigation of grafted cell doses has been lacking. Therefore, this study aimed to evaluate the different doses of MSCs on treatment of type 1 diabetes in mouse models. MSCs were isolated and expanded from human adipose tissue. Streptozotocin (STZ)-induced diabetic mice were divided into two groups that were intravenously transfused with two different doses of human MSCs: 106 or 2.106 cells/mouse. After transplantation, both grafted and placebo mice were monitored weekly for their blood glucose levels, glucose and insulin tolerance, pancreatic structural changes, and insulin production for 56 days after transplantation. The results showed that the higher dose of MSCs (2.106 cells/mouse) remarkably reduced death rate. The death rates were 50%, 66%, and 0% in placebo group, low-dose (1.106 MSCs) group, and high-dose (2.106 MSCs) group, respectively, after 56 days of treatment. Moreover, blood glucose levels were lower for the high-dose group compared to other groups. Glucose and insulin tolerance, as well as insulin production, were significantly improved in mice transplanted with 2.106 cells. The histochemical analyses also support these results. Thus, a higher (e.g., 2.106) dose of MSCs may be an effective dose for treatment of type 1 diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Transplante de Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Animais , Glicemia , Teste de Tolerância a Glucose , Humanos , Infusões Intravenosas , Insulina/sangue , Células-Tronco Mesenquimais/citologia , Camundongos
7.
Appl Environ Microbiol ; 83(5)2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28115380

RESUMO

During fermentative growth in natural and industrial environments, Saccharomyces cerevisiae must redistribute the available nitrogen from multiple exogenous sources to amino acids in order to suitably fulfill anabolic requirements. To exhaustively explore the management of this complex resource, we developed an advanced strategy based on the reconciliation of data from a set of stable isotope tracer experiments with labeled nitrogen sources. Thus, quantifying the partitioning of the N compounds through the metabolism network during fermentation, we demonstrated that, contrary to the generally accepted view, only a limited fraction of most of the consumed amino acids is directly incorporated into proteins. Moreover, substantial catabolism of these molecules allows for efficient redistribution of nitrogen, supporting the operative de novo synthesis of proteinogenic amino acids. In contrast, catabolism of consumed amino acids plays a minor role in the formation of volatile compounds. Another important feature is that the α-keto acid precursors required for the de novo syntheses originate mainly from the catabolism of sugars, with a limited contribution from the anabolism of consumed amino acids. This work provides a comprehensive view of the intracellular fate of consumed nitrogen sources and the metabolic origin of proteinogenic amino acids, highlighting a strategy of distribution of metabolic fluxes implemented by yeast as a means of adapting to environments with changing and scarce nitrogen resources.IMPORTANCE A current challenge for the wine industry, in view of the extensive competition in the worldwide market, is to meet consumer expectations regarding the sensory profile of the product while ensuring an efficient fermentation process. Understanding the intracellular fate of the nitrogen sources available in grape juice is essential to the achievement of these objectives, since nitrogen utilization affects both the fermentative activity of yeasts and the formation of flavor compounds. However, little is known about how the metabolism operates when nitrogen is provided as a composite mixture, as in grape must. Here we quantitatively describe the distribution through the yeast metabolic network of the N moieties and C backbones of these nitrogen sources. Knowledge about the management of a complex resource, which is devoted to improvement of the use of the scarce N nutrient for growth, will be useful for better control of the fermentation process and the sensory quality of wines.


Assuntos
Fermentação , Nitrogênio/química , Nitrogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Aminoácidos/metabolismo , Biomassa , Carbono/metabolismo , Meios de Cultura/análise , Indústria Alimentícia , Microbiologia de Alimentos , Sucos de Frutas e Vegetais , Marcação por Isótopo , Redes e Vias Metabólicas , Metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Açúcares/metabolismo , Vitis/química , Vinho/análise
8.
J Nat Prod ; 79(8): 2053-9, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27466882

RESUMO

Human pancreatic cancer cell lines such as PANC-1 have an altered metabolism, enabiling them to tolerate and survive under extreme conditions of nutrient starvation. The search for candidates that inhibit their viability during nutrition starvation represents a novel antiausterity strategy in anticancer drug discovery. A methanol extract of the bark of Mangifera indica was found to inhibit the survival of PANC-1 human pancreatic cancer cells preferentially under nutrient-deprived conditions with a PC50 value of 15.5 µg/mL, without apparent toxicity, in normal nutrient-rich conditions. Chemical investigation on this bioactive extract led to the isolation of 19 compounds (1-19), including two new cycloartane-type triterpenes, mangiferolate A (1) and mangiferolate B (2). The structures of 1 and 2 were determined by NMR spectroscopic analysis. Among the isolated compounds, mangiferolate B (2) and isoambolic acid (12) exhibited potent preferential cytotoxicity against PANC-1 human pancreatic cancer cells under the nutrition-deprived condition with PC50 values of 11.0 and 4.8 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Mangifera/química , Neoplasias Pancreáticas/tratamento farmacológico , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Triterpenos/química , Vietnã
9.
Cell Tissue Bank ; 17(2): 289-302, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26679929

RESUMO

Umbilical cord (UC) is a rich source of rapidly proliferating mesenchymal stem cells (MSCs) that are easily cultured on a large-scale. Clinical applications of UC-MSCs include graft-versus-host disease, and diabetes mellitus types 1 and 2. UC-MSCs should be isolated and proliferated according to good manufacturing practice (GMP) with animal component-free medium, quality assurance, and quality control for their use in clinical applications. This study developed a GMP standard protocol for UC-MSC isolation and culture. UC blood and UC were collected from the same donors. Blood vasculature was removed from UC. UC blood was used as a source of activated platelet rich plasma (aPRP). Small fragments (1-2 mm(2)) of UC membrane and Wharton's jelly were cut and cultured in DMEM/F12 medium containing 1 % antibiotic-antimycotic, aPRP (2.5, 5, 7.5 and 10 %) at 37 °C in 5 % CO2. The MSC properties of UC-MSCs at passage 5 such as osteoblast, chondroblast and adipocyte differentiation, and markers including CD13, CD14, CD29, CD34, CD44, CD45, CD73, CD90, CD105, and HLA-DR were confirmed. UC-MSCs also were analyzed for karyotype, expression of tumorigenesis related genes, cell cycle, doubling time as well as in vivo tumor formation in NOD/SCID mice. Control cells consisted of UC-MSCs cultured in DMEM/F12 plus 1 % antibiotic-antimycotic, and 10 % fetal bovine serum (FBS). All UC-MSC (n = 30) samples were successfully cultured in medium containing 7.5 and 10 % aPRP, 92 % of samples grew in 5.0 % aPRP, 86 % of samples in 2.5 % aPRP, and 72 % grew in 10 % FBS. UC-MSCs in these four groups exhibited similar marker profiles. Moreover, the proliferation rates in medium with PRP, especially 7.5 and 10 %, were significantly quicker compared with 2.5 and 5 % aPRP or 10 % FBS. These cells maintained a normal karyotype for 15 sub-cultures, and differentiated into osteoblasts, chondroblasts, and adipocytes. The analysis of pluripotent cell markers showed UC-MSCs maintained the expression of the oncogenes Nanog and Oct4 after long term culture but failed to transfer tumors in NOD/SCID mice. Replacing FBS with aPRP in the culture medium for UC tissues allowed the successful isolation of UC-MSCs that satisfy the minimum standards for clinical applications.


Assuntos
Separação Celular/métodos , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Cromossomos Humanos/metabolismo , Regulação da Expressão Gênica , Genes Supressores de Tumor , Humanos , Cariotipagem , Células-Tronco Mesenquimais/metabolismo , Mesoderma/citologia , Camundongos Nus , Camundongos SCID , Oncogenes
10.
Xenotransplantation ; 22(5): 356-67, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26381493

RESUMO

BACKGROUND: During the process of islet isolation, pancreatic enzymes are activated and released, adversely affecting islet survival and function. We hypothesize that the exocrine component of pancreases harvested from pre-weaned juvenile pigs is immature and hence pancreatic tissue from these donors is protected from injury during isolation and prolonged tissue culture. METHODS: Biopsy specimens taken from pancreases harvested from neonatal (5-10 days), pre-weaned juvenile (18-22 days), weaned juvenile (45-60 days), and young adult pigs (>90 days) were fixed and stained with hematoxylin and eosin. Sections were examined under a fluorescent microscope to evaluate exocrine zymogen fluorescence intensity (ZFI) and under an electron microscope to evaluate exocrine zymogen granule density (ZGD). RESULTS: Exocrine content estimation showed significantly lower ZFI and ZGD in juvenile pig pancreases (1.5 ± 0.04 U/µm(2) , ZFI; 1.03 ± 0.07 × 10(3) /100 µm(2) , ZGD) compared to young adult pigs (2.4 ± 0.05U/µm(2) , ZFI; 1.53 ± 0.08 × 10(3) /100 µm(2) ZGD). Islets in juvenile pig pancreases were on average smaller (105.2 ± 11.2 µm) than islets in young adult pigs (192 ± 7.7 µm), but their insulin content was comparable (80.9 ± 2.2% juvenile; 84.2 ± 0.3% young adult, P > 0.05). All data expressed as mean ± SEM. CONCLUSION: Porcine islet xenotransplantation continues to make strides toward utilization in clinical trials of type 1 diabetes. Porcine donor age and weaning status influence the extent of exocrine maturation of the pancreas. Juvenile porcine pancreases may represent an alternative donor source for islet xenotransplantation as their exocrine component is relatively immature; this preserves islet viability during extended tissue culture following isolation.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Pâncreas/crescimento & desenvolvimento , Coleta de Tecidos e Órgãos/métodos , Transplante Heterólogo , Desmame , Fatores Etários , Animais , Masculino , Pâncreas/anatomia & histologia , Pâncreas/cirurgia , Vesículas Secretórias , Suínos
11.
PLoS One ; 19(2): e0288526, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324614

RESUMO

It was necessary to have a tool that could predict the amount of protein and optimize the gene sequences to produce recombinant proteins efficiently. The Transim model published by Tuller et al. in 2018 can calculate the translation rate in E. coli using features on the mRNA sequence, achieving a Spearman correlation with the amount of protein per mRNA of 0.36 when tested on the dataset of operons' first genes in E. coli K-12 MG1655 genome. However, this Spearman correlation was not high, and the model did not fully consider the features of mRNA and protein sequences. Therefore, to enhance the prediction capability, our study firstly tried expanding the testing dataset, adding genes inside the operon, and using the microarray of the mRNA expression data set, thereby helping to improve the correlation of translation rate with the amount of protein with more than 0.42. Next, the applicability of 6 traditional machine learning models to calculate a "new translation rate" was examined using initiation rate and elongation rate as inputs. The result showed that the SVR algorithm had the most correlated new translation rates, with Spearman correlation improving to R = 0.6699 with protein level output and to R = 0.6536 with protein level per mRNA. Finally, the study investigated the degree of improvement when combining more features with the new translation rates. The results showed that the model's predictive ability to produce a protein per mRNA reached R = 0.6660 when using six features, while the correlation of this model's final translation rate to protein level was up to R = 0.6729. This demonstrated the model's capability to predict protein expression of a gene, rather than being limited to predicting expression by an mRNA and showed the model's potential for development into gene expression predicting tools.


Assuntos
Escherichia coli K12 , Escherichia coli , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli K12/genética , Escherichia coli K12/metabolismo , Genoma , Proteínas Recombinantes/metabolismo , Biossíntese de Proteínas/genética
12.
Mol Plant Pathol ; 25(7): e13491, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961768

RESUMO

Root-knot nematodes (RKNs) are microscopic parasitic worms able to infest the roots of thousands of plant species, causing massive crop yield losses worldwide. They evade the plant's immune system and manipulate plant cell physiology and metabolism to transform a few root cells into giant cells, which serve as feeding sites for the nematode. RKN parasitism is facilitated by the secretion in planta of effector molecules, mostly proteins that hijack host cellular processes. We describe here a conserved RKN-specific effector, effector 12 (EFF12), that is synthesized exclusively in the oesophageal glands of the nematode, and we demonstrate its function in parasitism. In the plant, MiEFF12 localizes to the endoplasmic reticulum (ER). A combination of RNA-sequencing analysis and immunity-suppression bioassays revealed the contribution of MiEFF12 to the modulation of host immunity. Yeast two-hybrid, split luciferase and co-immunoprecipitation approaches identified an essential component of the ER quality control system, the Solanum lycopersicum plant bap-like (PBL), and basic leucine zipper 60 (BZIP60) proteins as host targets of MiEFF12. Finally, silencing the PBL genes in Nicotiana benthamiana decreased susceptibility to Meloidogyne incognita infection. Our results suggest that EFF12 manipulates PBL function to modify plant immune responses to allow parasitism.


Assuntos
Retículo Endoplasmático , Tylenchoidea , Animais , Retículo Endoplasmático/metabolismo , Tylenchoidea/fisiologia , Tylenchoidea/patogenicidade , Proteínas de Helminto/metabolismo , Proteínas de Helminto/genética , Imunidade Vegetal , Nicotiana/parasitologia , Nicotiana/imunologia , Nicotiana/genética , Solanum lycopersicum/parasitologia , Solanum lycopersicum/imunologia , Solanum lycopersicum/genética , Doenças das Plantas/parasitologia , Doenças das Plantas/imunologia , Raízes de Plantas/parasitologia , Raízes de Plantas/imunologia , Interações Hospedeiro-Parasita
13.
RSC Med Chem ; 15(3): 1046-1054, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516598

RESUMO

Plants of the Zingiberaceae family, specifically those belonging to the Curcuma species, are commonly under consideration as potential therapeutic agents for the management of gastrointestinal diseases. In this study, we carried out a phytochemical study on Curcuma aromatica Salisb. (or so-called "Nghe trang" in Vietnamese) grown in Vietnam, which yields three newly discovered 3,5-diacetoxy diarylheptanoids (1-3) and six known 3,5-dihydroxyl diarylheptanoids (4-9). The bioactivity assessment shows that all isolated compounds, except compounds 3, 7, and 8, could inhibit urease. Compounds 4 and 9 significantly inhibit urease, with an IC50 value of 9.6 and 21.4 µM, respectively, more substantial than the positive control, hydroxyurea (IC50 = 77.4 µM). The structure-activity relationship (SAR) of linear diarylheptanoids was also established, suggesting that the hydroxyl groups at any position of skeleton diarylheptanoids are essential for exerting anti-urease action. Through a comparative analysis of the binding sites of hydroxyurea and diarylheptanoid compounds via our constructed in silico model, the mechanism of action of diarylheptanoid compounds is predicted to bind to the dynamic region close to the dinickel active center, resulting in a loss of catalytic activity. Such insights certainly help design and/or find diarylheptanoid-based compounds for treating gastric ulcers through inhibiting urease.

14.
PLoS Negl Trop Dis ; 18(1): e0011922, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38289968

RESUMO

BACKGROUND: Dengue is one of the most common diseases in the tropics and subtropics. Whilst mortality is a rare event when adequate supportive care can be provided, a large number of patients get hospitalised with dengue every year that places a heavy burden on local health systems. A better understanding of the support required at the time of hospitalisation is therefore of critical importance for healthcare planning, especially when resources are limited during major outbreaks. METHODS: Here we performed a retrospective analysis of clinical data from over 1500 individuals hospitalised with dengue in Vietnam between 2017 and 2019. Using a broad panel of potential biomarkers, we sought to evaluate robust predictors of prolonged hospitalisation periods. RESULTS: Our analyses revealed a lead-time bias, whereby early admission to hospital correlates with longer hospital stays - irrespective of disease severity. Importantly, taking into account the symptom duration prior to hospitalisation significantly affects observed associations between hospitalisation length and previously reported risk markers of prolonged stays, which themselves showed marked inter-annual variations. Once corrected for symptom duration, age, temperature at admission and elevated neutrophil-to-lymphocyte ratio were found predictive of longer hospitalisation periods. CONCLUSION: This study demonstrates that the time since dengue symptom onset is one of the most significant predictors for the length of hospital stays, independent of the assigned severity score. Pre-hospital symptom durations need to be accounted for to evaluate clinically relevant biomarkers of dengue hospitalisation trajectories.


Assuntos
Dengue Grave , Humanos , Dengue Grave/diagnóstico , Dengue Grave/epidemiologia , Estudos Retrospectivos , Hospitalização , Tempo de Internação , Biomarcadores
15.
Microb Genom ; 10(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739115

RESUMO

Aeromonas spp. are commonly found in the aquatic environment and have been responsible for motile Aeromonas septicemia (MAS) in striped catfish, resulting in significant economic loss. These organisms also cause a range of opportunistic infections in humans with compromised immune systems. Here, we conducted a genomic investigation of 87 Aeromonas isolates derived from diseased catfish, healthy catfish and environmental water in catfish farms affected by MAS outbreaks in eight provinces in Mekong Delta (years: 2012-2022), together with 25 isolates from humans with bloodstream infections (years: 2010-2020). Genomics-based typing method precisely delineated Aeromonas species while traditional methods such as aerA PCR and MALDI-TOF were unable identify A. dhakensis. A. dhakensis was found to be more prevalent than A. hydrophila in both diseased catfish and human infections. A. dhakensis sequence type (ST) 656 followed by A. hydrophila ST251 were the predominant virulent species-lineages in diseased catfish (43.7 and 20.7 %, respectively), while diverse STs were found in humans with bloodstream infections. There was evidence of widespread transmission of ST656 and ST251 on striped catfish in the Mekong Delta region. ST656 and ST251 isolates carried a significantly higher number of acquired antimicrobial resistance (AMR) genes and virulence factors in comparison to other STs. They, however, exhibited several distinctions in key virulence factors (i.e. lack of type IV pili and enterotoxin ast in A. dhakensis), AMR genes (i.e. presence of imiH carbapenemase in A. dhakensis), and accessory gene content. To uncover potential conserved proteins of Aeromonas spp. for vaccine development, pangenome analysis has unveiled 2202 core genes between ST656 and ST251, of which 78 proteins were in either outer membrane or extracellular proteins. Our study represents one of the first genomic investigations of the species distribution, genetic landscape, and epidemiology of Aeromonas in diseased catfish and human infections in Vietnam. The emergence of antimicrobial resistant and virulent A. dhakensis strains underscores the needs of enhanced genomic surveillance and strengthening vaccine research and development in preventing Aeromonas diseases in catfish and humans, and the search for potential vaccine candidates could focus on Aeromonas core genes encoded for membrane and secreted proteins.


Assuntos
Aeromonas , Peixes-Gato , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Sepse , Animais , Peixes-Gato/microbiologia , Vietnã/epidemiologia , Aeromonas/genética , Aeromonas/isolamento & purificação , Aeromonas/classificação , Aeromonas/patogenicidade , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Negativas/epidemiologia , Humanos , Sepse/microbiologia , Sepse/veterinária , Sepse/epidemiologia , Doenças dos Peixes/microbiologia , Filogenia , Genômica , Genoma Bacteriano , Fatores de Virulência/genética , Antibacterianos/farmacologia
16.
Nanotechnology ; 24(50): 505304, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24285551

RESUMO

We report here a fast and reliable hard anodization process to make asymmetric anodic aluminum oxide (AAO) membranes which can serve as a template for large pitch-distance nanostructures. In order to make larger pitch distances possible, the common burning failure associated with the high current density during the conventional constant voltage hard anodization, especially at a voltage higher than a known limit, i.e., 155 V for oxalic acid, was effectively suppressed by using a burning-protective agent. A new self-ordering regime beyond the voltage limit was observed with a different voltage-interpore distance relationship of 2.2 nm V(-1) compared to the reported 2.0 nm V(-1) for hard anodization. Combining a sulfuric acid mild anodization with this new regime of hard anodization, we further demonstrate a scalable process to make an asymmetric membrane with size up to ~47 mm in diameter and ~60 µm in thickness. This free-standing membrane can be used as a template for novel nanopatterned structures such as arrays of quantum dots, nanowires or nanotubes with diameters of a few tens of nanometers and pitch distance of over 400 nm.

17.
Nat Prod Res ; : 1-6, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36606539

RESUMO

From the EtOAc extract of the wood of the stems of Taxotrophis ilicifolius (Moraceae), two new secondary metabolites, named taxotrophises A (1) and B (2), were isolated, together with five known compounds (3-7). Their chemical structures have been elucidated by extensive NMR spectroscopic analysis. All isolated compounds have been evaluated for α-glucosidase inhibitory activity. In the present work, compounds 1 and 4 showed the strongest α-glucosidase inhibitory activity with IC50 values of 6.5 and 1.5 µM, respectively, and stronger than that of a positive control, acarbose (IC50; 214.5 µM).

18.
bioRxiv ; 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37645757

RESUMO

Patient-specific, human-based cellular models that integrate biomimetic BBB, immune, and myelinated neuron components are critically needed to enable translationally relevant and accelerated discovery of neurological disease mechanisms and interventions. By engineering a brain-mimicking 3D hydrogel and co-culturing all six major brain cell types derived from patient iPSCs, we have constructed, characterized, and utilized a multicellular integrated brain (miBrain) immuno-glial-neurovascular model with in vivo- like hallmarks. As proof of principle, here we utilized the miBrain to model Alzheimer's Disease pathologies associated with APOE4 genetic risk. APOE4 miBrains differentially exhibit amyloid aggregation, tau phosphorylation, and astrocytic GFAP. Unlike the co-emergent fate specification of glia and neurons in organoids, miBrains integrate independently differentiated cell types in a modular system with unique utility for elucidating cell-type specific contributions to pathogenesis. We here harness this feature to identify that risk factor APOE4 in astrocytes promotes tau pathogenesis and neuronal dysregulation through crosstalk with microglia. One-Sentence Summary: A novel patient-specific brain model with BBB, neuronal, immune, and glial components was developed, characterized, and harnessed to model Alzheimer's Disease-associated pathologies and APOE4 genetic risk.

19.
Nat Prod Res ; : 1-6, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37403594

RESUMO

From the EtOAc-soluble extract of the rhizomes of Zingiber montanum (J.Koenig) Link ex A.Dietr., a novel diphenylbutenoid, montadinin A (1) and a previously unreported phenylbutenoid compound, 1-(3,4-dimethoxyphenyl)but-3-en-2-ol (7), in natural source were isolated. Additionally, seven known phenylbutenoids were also identified. The structures of all compounds were elucidated through NMR spectroscopic interpretation. Compounds cis-3-(3,4-dimethoxyphenyl)-4-[(E)-3,4-dimethoxystyryl]cyclohex-1-ene (2), cis-4-[(E)-3,4-dimethoxystyryl]-3-(2,4,5-trimethoxyphenyl)cyclohex-1-ene (3), trans-3-(3,4,-dimethoxyphenyl)-4-[(E)-2,4,5-trimethoxystyryl]cyclohex-1-ene (5), and cis-3-(3,4-dimethoxyphenyl)-4-[(Z)-2,4,5-trimethoxylstyryl]cyclohex-1-ene (6) showed weak cytotoxicity against HepG2 cells with IC50 values of 122.9, 127.3, 257.5, and 168.5 µM, respectively.

20.
Viruses ; 15(10)2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37896852

RESUMO

The prevalence of hepatitis E virus (HEV) in the Vietnamese population remains underestimated. The aim of the present study was to investigate the seroprevalence of HEV IgG/IgM antibodies and the presence of HEV RNA in blood donors as a part of epidemiological surveillance for transfusion-transmitted viruses. Serum samples from blood donors (n = 553) were analysed for markers of past (anti-HEV IgG) and recent/ongoing (anti-HEV IgM) HEV infections. In addition, all serum samples were subsequently tested for HEV RNA positivity. The overall prevalence of anti-HEV IgG was 26.8% (n = 148/553), while the seroprevalence of anti-HEV IgM was 0.5% (n = 3/553). Anti-HEV IgG seroprevalence in male and female donors was similar (27.1% and 25.5%, respectively). A higher risk of hepatitis E exposure was observed with increasing age. None of the blood donors were HEV RNA positive, and there was no evidence of HEV viraemia. Although the absence of HEV viraemia in blood donors from Northern Vietnam is encouraging, further epidemiological surveillance in other geographical regions is warranted to rule out transfusion-transmitted HEV.


Assuntos
Vírus da Hepatite E , Hepatite E , Masculino , Humanos , Feminino , Vírus da Hepatite E/genética , Doadores de Sangue , Estudos Soroepidemiológicos , Viremia/epidemiologia , População do Sudeste Asiático , Vietnã/epidemiologia , Anticorpos Anti-Hepatite , RNA Viral/genética , Imunoglobulina G , Imunoglobulina M
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