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1.
Chaos ; 31(2): 021102, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33653040

RESUMO

This paper proposes a universal method for a cascade chaotic system (CCS). CCSs may own better performances, including larger maximum Lyapunov exponents, extended full mapping range of chaos, and more coefficient variations. The chaos-cascade theorems had been proposed in our previous papers, which are more suitable for discrete chaotic systems with the same domain. In this paper, we further improve a universal method to normalize arbitrary discrete chaotic systems for constructing a series of CCSs. Besides, the inheritance and enhancement of robustness from the subsystem are first explored for CCSs. Finally, the designed CCS is implemented on field programmable gate array board. The generated chaotic sequences are obtained by an oscilloscope and tested by NIST software.

2.
Acad Radiol ; 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33303346

RESUMO

RATIONALE AND OBJECTIVES: To investigate the value of diffusion-weighted magnetic resonance imaging for the prediction of microvascular invasion (MVI) of Hepatocellular Carcinoma (HCC) using Convolutional Neural Networks (CNN). MATERIAL AND METHODS: This study was approved by the local institutional review board and the patients' informed consent was waived. Consecutive 97 subjects with 100 HCCs from July 2012 to October 2018 with surgical resection were retrieved. All subjects with diffusion-weighted imaging (DWI) examinations were performed with single-shot echo-planar imaging in a breath-hold routine. DWI parameters were three b values of 0,100,600 sec/mm2. First, apparent diffusion coefficients (ADC) images were computed by mono-exponentially fitting the three b-value points. Then, multiple 2D axial patches (28 × 28) of HCCs from b0, b100, b600, and ADC images were extracted to increase the dataset for training the CNN model. Finally, the fusion of deep features derived from three b value images and ADC was conducted based on the CNN model for MVI prediction. The data set was split into the training set (60 HCCs) and the independent test set (40 HCCs). The output probability of the deep learning model in the MVI prediction of HCCs was assessed by the independent student's t-test for data following a normal distribution and Mann-Whitney U test for data violating the normal distribution. Receiver operating characteristic curve and area under the curve (AUC) were also used to assess the performance for MVI prediction of HCCs in the fixed test set. RESULTS: Deep features in b600 images yielded better performance (AUC = 0.74, p = 0.004) for MVI prediction than b0 (AUC = 0.69, p = 0.023) and b100 (AUC = 0.734, p = 0.011). Comparatively, deep features in the ADC map obtained lower performance (AUC = 0.71, p = 0.012) than that of the higher b value images (b600) for MVI prediction. Furthermore, the fusion of deep features from the b0, b100, b600, and ADC images yielded the best results (AUC = 0.79, p = 0.002) for MVI prediction. CONCLUSION: Fusion of deep features derived from DWI images concerning the three b-value images and the ADC image yields better performance for MVI prediction.

3.
Chaos ; 30(10): 103123, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33138451

RESUMO

This paper presents a chaotic circuit based on a nonvolatile locally active memristor model, with non-volatility and local activity verified by the power-off plot and the DC V-I plot, respectively. It is shown that the memristor-based circuit has no equilibrium with appropriate parameter values and can exhibit three hidden coexisting heterogeneous attractors including point attractors, periodic attractors, and chaotic attractors. As is well known, for a hidden attractor, its attraction basin does not intersect with any small neighborhood of any unstable equilibrium. However, it is found that some attractors of this circuit can be excited from an unstable equilibrium in the locally active region of the memristor, meaning that its basin of attraction intersects with neighborhoods of an unstable equilibrium of the locally active memristor. Furthermore, with another set of parameter values, the circuit possesses three equilibria and can generate self-excited chaotic attractors. Theoretical and simulated analyses both demonstrate that the local activity and an unstable equilibrium of the memristor are two reasons for generating hidden attractors by the circuit. This chaotic circuit is implemented in a digital signal processing circuit experiment to verify the theoretical analysis and numerical simulations.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33097514

RESUMO

Heterotrophic microbes play a key role in remineralizing organic material in the coastal ocean. While there is a significant body of literature examining heterotrophic bacterioplankton and phytoplankton communities, much less is known about the diversity, dynamics, and ecology of eukaryotic heterotrophs. Here we focus on the Labyrinthulomycetes, a fungus-like protistan group whose biomass can exceed that of the bacterioplankton in coastal waters. We examined their diversity and community structure in a weekly temperate coastal ocean time series. Their seasonal community patterns were related to temperature, insolation, dissolved inorganic carbon, fungal abundance, ammonia, chlorophyll a, pH, and other environmental variables. Similar to the bacterioplankton, annual community patterns of the Labyrinthulomycetes were dominated by a few persistent taxa with summer or winter preferences. However, like the patterns of fungi at this site, the majority of the Labyrinthulomycetes phylotypes occurred mostly as short, reoccurring, season-specific blooms. Furthermore, some of specific phylotypes of Labyrinthulomycetes displayed time-lagged correlations or co-occurrences with bacterial, algal, or fungal phylotypes, suggesting their potentially multifaceted involvement in the marine food webs. Overall, this study reports niche partitioning between closely-related Labyrinthulomycetes and identifies distinct ecotypes and temporal patterns compared to bacterioplankton and fungi.IMPORTANCE Increasing evidence has shown heterotrophic microeukaryotes are an important component in global marine ecosystems, while their diversity and ecological functions remain largely unknown. Without appropriately incorporating these organisms into the food web models, our current understanding of marine microbial community ecology is incomplete, which may further hamper broader studies of biogeochemistry and climate change. This study focuses on a major group of unicellular fungus-like protists (Labyrinthulomycetes) and reveals their distinct annual community patterns relative to fungi and bacteria. Results of our observations provide new information on the community structure and ecology of this protistan group and shed light on the intricate ecological roles of unicellular heterotrophic eukaryotes in the coastal oceans.

5.
Bioresour Technol ; 318: 124273, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33099103

RESUMO

Docosahexaenoic acid (DHA, C22:6) production in thraustochytrids is known to be mediated independently through polyunsaturated fatty acid (PUFA) synthase and fatty acid synthase systems. This study elucidates the unresolved effects of different carbon and nitrogen sources on the functionality of PUFA synthase subunit B (pfaB) and corresponding DHA production in Thraustochytriidae sp. PKU#SW8. Carbon and nitrogen sources showed significant effect on the pfaB gene expression and DHA production patterns, but these patterns did not correspond with each other, suggesting the strong role of substrates in differential induction of the two synthase systems. Nitrogen starvation increased DHA yield in parallel with upregulated gene expression, showing strong indication of PUFA synthase activity in N-deficient culture. The fully functional catalytic activity of PfaB subunit from strain PKU#SW8 in a heterologous host was also demonstrated. This study provides the direct evidence of pfaB gene actively for DHA biosynthesis in Thraustochytriidae sp. PKU#SW8.


Assuntos
Carbono , Estramenópilas , Ácidos Docosa-Hexaenoicos , Ácidos Graxos Insaturados , Nitrogênio , Estramenópilas/genética
6.
Exp Ther Med ; 20(6): 171, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33101464

RESUMO

Uncontrolled inflammatory cytokine production by macrophages contributes to numerous conditions, including infection, endotoxemia and sepsis. A previous study proposed that endoplasmic reticulum (ER) stress acts as an essential process in inflammatory cytokine production by macrophages. The present study used a mouse sepsis model and in vitro macrophages to demonstrate that homeodomain-interacting protein kinase 2 (HIPK2) sustained cytokine production in an ER stress-dependent manner. HIPK2 expression was upregulated in the early phase of lipopolysaccharide stimulation. HIPK2 knockdown attenuated IL-6 and TNF-α production, and p65 phosphorylation in macrophages. Furthermore, the attenuated cytokine production was abolished by the ER stress agonist tunicamycin. The activation of ER stress increased the levels of IL-6 and TNF-α, and the phosphorylation of p65, in macrophages following knockdown of HIPK2. Furthermore, HIPK2 inhibition attenuated the production of IL-6 and TNF-α in vitro and in vivo. Therefore, HIPK2 sustained inflammatory cytokine production by promoting ER stress in macrophages. Targeting HIPK2 may be a potential strategy for the management of uncontrolled inflammation in clinical settings.

7.
Sci Total Environ ; : 142635, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33071110

RESUMO

Mycoplankton are a diverse and ubiquitous component of marine environments with a suggested role in ocean biogeochemical cycling. Thus far, the patterns of their abundance, structure, and function against spatial environmental heterogeneity remains poorly understood. Based on in silico and experimental evaluation of multiple markers, we adopted the ITS1 region to determine the composition, guilds, and metabolic potential of mycoplankton communities in contrasting marine environments. The trophic status of estuarine (SB1 and SB2) and coastal (DB1 and DB2) sites, but not oceanic (OS) site, was the major factor that determined their abundances. While ascomycetous fungi dominated the estuarine and coastal sites, basidiomycetous fungi were found to dominate the oceanic site. The zoosporic fungi were relatively more abundant in SB1 and DB2 sites compared to the other sites. The relative abundances of the core fungi, namely Cystobasidium, Phlebia, Rhodotorula, Trichoderma, Alternaria, Penicillium, Malassezia, and Aspergillus varied widely across the sites. Additionally, several fungal genera unique to each site were also identified. DB2 site exhibited the lowest fungal richness while the OS site the highest. Conversely, the diversity and evenness were the lowest for the OS site but highest for the SB1 site. Temperature, pH, and chlorophyll-a were strongly associated with spatial diversity patterns. Of the 11 assigned guilds, some guilds particularly were not detected, including plant pathogen-wood saprotroph in DB2, the endophyte-plant pathogen in OS, the animal pathogen in SB1, and fungal parasite in DB1 and SB2. Within core functions-metabolism of amino acids, carbohydrates and energy, fatty acids and lipids, nitrogen, sulfur, and other compounds-several pathways showed spatial variations. Overall, this study not just broadens the taxonomic and metabolic repertoire of marine mycoplankton but also provides the first evidence of how these are shaped by site-scale environmental heterogeneity.

8.
Respirology ; 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32954622

RESUMO

BACKGROUND AND OBJECTIVE: The purpose of this study was to report the characteristics and long-term survival of patients with CTEPH treated in three distinct ways: PEA, BPA and medical therapy. METHODS: Patients diagnosed with CTEPH were included in the registry that was set up in 18 centres from August 2009 to July 2018. The characteristics and survival of patients with CTEPH receiving the different treatments were reported. Prognostic factors were evaluated by Cox regression model. RESULTS: A total of 593 patients with CTEPH were included. Eighty-one patients were treated with PEA, 61 with BPA and 451 with drugs. The estimated survival rates at 1, 3, 5 and 8 years were, respectively, 95.2%, 84.6%, 73.4% and 66.6% in all patients; 92.6%, 89.6%, 87.5% and 80.2% in surgical patients; and 95.4%, 88.3%, 71.0% and 64.1% in medically treated patients. The estimated survival rates at 1, 3, 5 and 7 years in patients treated with BPA were 96.7%, 88.1%, 70.0% and 70.0%, respectively. For all patients, PEA was an independent predictor of survival. Other independent risk factors were CHD, cardiac index, PVR, big endothelin-1, APE and 6MWD. CONCLUSION: This is the first multicentre prospective registry reporting baseline characteristics and estimated survival of patients with CTEPH in China. The long-term survival rates are similar to those of patients in the international and Spanish registries. PEA is an independent predictor of survival.

9.
J Med Chem ; 63(18): 10380-10395, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32816483

RESUMO

Chronic hepatitis C (CHC) is a major liver disease caused by the hepatitis C virus. The current standard of care for CHC can achieve cure rates above 95%; however, the drugs in current use are administered for a period of 8-16 weeks. A combination of safe and effective drugs with a shorter treatment period is highly desirable. We report synthesis and biological evaluation of a series of 2',3'- and 2',4'-substituted guanosine nucleotide analogues. Their triphosphates exhibited potent inhibition of the HCV NS5B polymerase with IC50 as low as 0.13 µM. In the HCV replicon assay, the phosphoramidate prodrugs of these analogues demonstrated excellent activity with EC50 values as low as 5 nM. A lead compound AL-611 showed high levels of the nucleoside 5'-triphosphate in vitro in primary human hepatocytes and in vivo in dog liver following oral administration.

10.
Medicine (Baltimore) ; 99(32): e21630, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769926

RESUMO

RATIONALE: Hepatocellular carcinoma (HCC) with intracavitary metastasis extending to the heart, also known as inferior vena cava (IVC) tumor thrombus, is an extremely rare late-stage disease with no effective treatment. In fact, the median survival is reportedly less than 2 months; thus, there is an urgent need for better treatment. PATIENT CONCERNS: In this study, a 48-year-old patient was admitted to our hospital to seek medical treatment for advanced primary HCC with right atrial metastasis. DIAGNOSIS: The patient was diagnosed as primary HCC with a large mass in the right lobe of the liver and intracavitary metastasis to the right atrium. INTERVENTIONS: A new surgical treatment of right hemihepatectomy, complete resection of the involved IVC and the right atrium thrombus, plus reconstruction of the resected IVC using autologous pericardial tube graft were undertaken and successfully performed. OUTCOMES: The patient recovered rapidly, and 14 days after the surgical procedures, he was discharged from the hospital. Notably, serum levels of alpha-fetoprotein dropped to normal range and no clinical signs of recurrence were observed during follow-up. LESSONS: This report highlights an unusual case of right atrial metastasis from HCC. The surgical treatment appeared to be suitable and effective, together with postoperative administration of lenvatinib, a tyrosine kinase multitarget inhibitor selected by performing whole-exome sequencing. These therapies have offered favorable clinical outcomes such as prevention of recurrence and prolongation of patient survival. In addition, clinicians may benefit from our experience for their future treatment of patients with similar clinical conditions.


Assuntos
Carcinoma Hepatocelular/cirurgia , Átrios do Coração/anormalidades , Metástase Neoplásica/diagnóstico , Carcinoma Hepatocelular/complicações , Átrios do Coração/cirurgia , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/fisiopatologia , Metástase Neoplásica/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Veia Cava Inferior/cirurgia
11.
Wound Repair Regen ; 28(6): 797-811, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32770808

RESUMO

This study aimed to improve the conventional rat burn wound model and to validate its utility. In total, 60 Sprague-Dawley rats were divided equally into the control and experimental groups. Altogether, 60 burn wound models with zones of stasis were created in each group. Gross visual assessments of the burn wounds were performed at 0, 24, and 48 hours after burn creation. The rates of necrosis in the zones of stasis were calculated, and the blood flow from the wounds was examined. Wound tissues were collected 48 hours after the burn and subjected to hematoxylin and eosin staining to determine whether the models were successfully established. The model success rates were calculated. The success rate of the burn wound models was significantly different between the control group and the experimental group (93.33% [56/60] vs 100%; P = .042). The Cronbach's alpha values and the respective correlation coefficients indicated that the stability of the zones of stasis in the models on the two sides of the spine was higher in the experimental group than in the control group. The standard deviations of the rate of necrosis, blood flow, and density of necrotic cells and apoptosis cell density, and inflammatory factor content in the zones of stasis were smaller in the experimental group than in the control group at 48 hours after model construction. This suggested that the stability of repeated procedures was higher in the experimental group than in the control group. The novel device for creating burns in animal models facilitated the effective creation of zones of stasis for rat burn wound models. Both the model success rate and stability were higher compared with the conventional model construction method. In addition, the use of the novel device can better align with the requirements of self-controlled studies.

12.
Int J Syst Evol Microbiol ; 70(7): 4186-4192, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32538740

RESUMO

A Gram-stain-negative, facultative anaerobic, red-pigmented, rod-shaped and non-motile strain (RC1_OXG_1FT) was isolated from deep sea water of the Indian Ocean. It was able to grow at pH 5-8 (optimum, pH 7), at 5-37 °C (optimum, 30 °C), and at salinity (% NaCl, w/v) of 0.5-5 % (optimum, 1-2 %). Catalase- and oxidase-positive. It had highest 16S rRNA gene similarity (96.7 %) to 'Sunxiuqinia dokdonensis' DH1T, followed by Sunxiuqinia faeciviva JAM-BA0302T (96.6 %), Sunxiuqinia elliptica CGMCC 1.9156T (96.2 %), Sunxiuqinia rutila HG677T (96.0 %) and species (less than 92.3 %) of other genera. It belongs to the genus Sunxiuqinia within the phylum Bacteroidetes, based on the phylogenetic analysis. The results of digital DNA-DNA hybridization and average nucleotide identity analyses indicated that the strain belonged to a novel species. Its genome size is 5,250, 885 bp, with DNA G+C content of 40.5 mol%. Genome analysis revealed that the strain possessed many genes involved in polysaccharide degradation, especially hemicellulose degradation, indicating that the strain could maintain its normal metabolism by using recalcitrant organic matter in the oligotrophic deep sea environment. Its principal fatty acids were anteiso-C15 : 0 and iso-C15 : 0 and the major polar lipids were phosphatidylethanolamine, two unidentified glycolipids, three unidentified phospholipids and two unidentified polar lipids. The isoprenoid quinone was MK-7. Based on the phenotypic, chemotaxonomic and genotypic data, the strain represents a novel species within the genus Sunxiuqinia, for which the name Sunxiuqinia indica sp. nov. is proposed. The type strain is RC1_OXG_1FT (=MCCC 1A13858T=KCTC 62805T).


Assuntos
Bacteroidetes/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Int J Syst Evol Microbiol ; 70(5): 3483-3490, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32369004

RESUMO

Two Gram-stain-negative, short rod-shaped and non-flagellated strains, designated 17-4AT and L52-1-41, were isolated from the surface seawater of the Indian Ocean and South China Sea, respectively. The 16S rRNA genes of the two strains shared sequence similarity of 99.45 %. Strain 17-4AT shared the highest 16S rRNA gene similarity of 98.02 % with Pusillimonas caeni EBR-8-1T, followed by Pusillimonas noertemannii BN9T (97.47 %), Pusillimonas soli MJ07T (96.93 %), Parapusillimonas granuli Ch07T (96.68 %), Pusillimonas ginsengisoli DCY25T (96.65 %), Eoetvoesia caeni PB3-7BT (96.63 %), Paracandidimonas caeni 24T (96.34 %), Castellaniella defragrans 54PinT (96.28 %) and Pusillimonas harenae B201T (96.05 %). L52-1-41 shared the highest 16S rRNA gene similarity of 97.74 % with Pusillimonas caeni EBR-8-1T, followed by Pusillimonas noertemannii BN9T (97.47 %), Pusillimonas soli MJ07T (96.65 %), Parapusillimonas granuli Ch07T (96.41 %), Pusillimonas ginsengisoli DCY25T (96.37 %), Eoetvoesia caeni PB3-7BT (96.35 %), Pusillimonas harenae B201T (96.28 %), and Paracandidimonas caeni 24T (96.06 %). The results of phylogenetic analyses indicated that 17-4AT and L52-1-41 formed a stable, distinct and highly supported lineage affiliated to the genus Pusillimonas. The results of the digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses indicated that they represented a single species. They featured similar genomic DNA G+C contents of 53.2-53.4 mol%. Activities of catalase and oxidase were negative for both strains. The fatty acids patterns of 17-4AT and L52-1-41 were most similar, mostly comprised of C16 : 0, C17 : 0cyclo, C18 : 0, C18 : 1ω9c and summed feature 8 (C18 : 1ω7c and/or C18 : 1 ω6c). The major polar lipids of the two strains were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and unidentified aminolipids. The respiratory quinone of the two strains was Q-8. Hence, on the basis of the phenotypic, chemotaxonomic and genotypic data presented in this study, we proposed the classification of both strains as representatives of a novel species named Pusillimonas maritima sp. nov., with the type strain 17-4AT (=MCCC 1A12670T=KCTC 62121T=NBRC 113794T), and another strain L52-1-41 (=MCCC 1A05046=KCTC 52313).


Assuntos
Alcaligenaceae/classificação , Filogenia , Água do Mar/química , Alcaligenaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
14.
Wound Repair Regen ; 28(4): 480-492, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32304258

RESUMO

Current wound scaffold dressing constructs can facilitate wound healing but do not exhibit antibacterial activity, resulting in high infection rates. We aimed to endow wound scaffold dressing with anti-infective ability by polyhexamethylenebiguanide (PHMB). We prepared PHMB hydrogel at varying concentrations (0.25%, 0.5%, 1%, 2%) and assessed release and cytotoxicity. PHMB hydrogel was added to the wound scaffold dressing to generate a PHMB hydrogel-modified wound scaffold dressing. Wound healing and infection prevention were evaluated using a full-thickness skin defect model in rats. In vitro, the hydrogel PHMB release time positively correlated with PHMB concentration, with 1% allowing sufficiently long release time to encompass the high-incidence period (3-5 days) of infection following wound scaffold dressing implantation. Implantation of 1% PHMB hydrogel into the skin did not cause adverse responses. in vitro cytotoxicity assays showed the PHMB hydrogel-modified wound scaffold dressing did not significantly affect proliferation of fibroblasts or vascular endothelial cells, 99.90% vs 99.84% for fibroblasts and 100.21% vs 99.28% for vascular endothelial cells at 21 days. Transplantation of PHMB hydrogel-modified wound scaffold dressing/unmodified wound scaffold dressing on the non-infected wounds of rats yielded no significant difference in relative vascularization rate, 47.40 vs 50.87 per view at 21 days, whereas bacterial content of the wound tissue in the PHMB hydrogel-modified wound scaffold dressing group was significantly lower than the unmodified wound scaffold dressing group, (1.80 ± 0.35) × 103 vs (9.34 ± 0.45) × 103 at 14 days. Prevalence of persistent wound infection in the rats receiving PHMB hydrogel-modified wound scaffold dressing transplantation onto infected wounds was significantly lower than the unmodified wound scaffold dressing group, 30% vs 100%. PHMB hydrogel-modified wound scaffold dressing exhibited suitable antibacterial ability, and its biological activity did not significantly differ from that of the unmodified wound scaffold dressing, thereby allowing it to effectively prevent infection following wound scaffold dressing implantation.

15.
Bioresour Technol ; 307: 123234, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32245673

RESUMO

Oleaginous microorganisms are among the most promising alternative sources of lipids for oleochemicals and biofuels. However, in the course of lipid production, reactive oxygen species (ROS) are generated inevitably as byproducts of aerobic metabolisms. Although excessive accumulation of ROS leads to lipid peroxidation, DNA damage, and protein denaturation, ROS accumulation has been suggested to enhance lipid synthesis in these microorganisms. There are many unresolved questions concerning this dichotomous view of ROS influence on lipid accumulation. These include what level of ROS triggers lipid overproduction, what mechanisms and targets are vital and whether ROS act as toxic byproducts or cellular messengers in these microorganisms? Here we review the current state of knowledge on ROS generation, antioxidative defense system, the dual effects of ROS on microbial lipid production, and ROS-induced lipid peroxidation and accumulation mechanisms. Toward the end, the review summarizes strategies that enhance lipid production based on ROS manipulation.


Assuntos
Biocombustíveis , Lipídeos , Antioxidantes , Peroxidação de Lipídeos , Espécies Reativas de Oxigênio
16.
Bioresour Technol ; 297: 122402, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761627

RESUMO

This study reports comparative evaluation of the growth and DHA productivity of the thraustochytrid strain Thraustochytriidae PKU#Mn16 fermented with seven different substrate feeding strategies. Of these strategies, fed-batch fermentation of the mixed substrate (glucose & glycerol) yielded the maximum growth (52.2 ±â€¯1.5 g/L), DHA yield (Yp/s: 8.65) and productivity (100.7 ±â€¯2.9 mg/L-h), comparable with those of previously reported Aurantiochytrium strains. Transcriptomics analyses revealed that glucose upregulated some genes of the fatty acid synthase pathway whereas glycerol upregulated a few genes of the polyketide synthase pathway. Co-fermentation of the mixed substrate differentially regulated genes of these two pathways and significantly enhanced the DHA productivity. Furthermore, some genes involved in DNA replication, phagosome, carbon metabolism, and ß-oxidation were also found to alter significantly during the mixed-substrate fermentation. Overall, this study provides a unique strategy for enhancing growth and DHA productivity of the strain PKU#Mn16 and the first insight into the mechanisms underlying mixed-substrate fermentation.


Assuntos
Carbono , Ácidos Docosa-Hexaenoicos , Vias Biossintéticas , Ácidos Graxos , Fermentação
17.
Biomed Pharmacother ; 123: 109793, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31884341

RESUMO

Despite advances in immunosuppressive therapies, acute rejection response is still a serious concern especially in the early phase after liver transplantation. This study aimed to evaluate whether blocking the TSP1-CD47 signaling pathway could attenuate the acute rejection after liver transplantation. An allogeneic mouse orthotopic liver transplantation model (Balb/c→C3H) with prolonged cold ischemic phase was used to induce severe IRI and lethal acute rejection. CD47mAb or isotype matched-control IgG2a was administered to donor liver during graft perfusion. Recipients were sacrificed at 1d, 3d, 5d and 7d after reperfusion. Blood samples were collected to evaluate serum alanine aminotransferase, total bilirubin, HMGB-1,TNF-α, IL-2 and INF-γ level. Flow cytometric analysis was used to detect the strength of innate and adaptive immune response. Liver tissue was obtained for HE, TUNEL staining and F4/80 immumohistochemical staining. Moreover, we conducted a mixed lymphocyte reaction treated with IgG2a or CD47mAb. Mice in CD47mAb-treated group demonstrated improved survival and significantly lower increase in Suzuki score, apoptosis index, acute rejection index, serum alanine aminotransferase, total bilirubin, HMGB-1, TNF-α, IL-2, INF-γ level and the degree of Kupffer cells' activation especially in the early phase of acute rejection. In addition, Pearson's correlation analysis confirmed significant correlation between Suzuki score/ALT and acute rejection index. The in vitro inhibition assay showed that CD47 blockade couldn't directly inhibit recipient lymphocyte proliferation. Based on the evidence that TSP1-CD47 signaling blockade with CD47mAb could alleviate acute rejection by reducing the extent of IRI after liver transplantation indirectly, this study provided a basis for new interventions and management methods to support better transplant outcomes.


Assuntos
Antígeno CD47/antagonistas & inibidores , Rejeição de Enxerto/patologia , Transplante de Fígado , Traumatismo por Reperfusão/patologia , Doença Aguda , Animais , Anticorpos Monoclonais/farmacologia , Antígeno CD47/metabolismo , Proliferação de Células/efeitos dos fármacos , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Fígado/patologia , Teste de Cultura Mista de Linfócitos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/imunologia , Análise de Sobrevida , Transplante Homólogo
18.
Org Lett ; 22(2): 405-409, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31874039

RESUMO

Herpotrichones A and B (1 and 2), two intermolecular [4 + 2] adducts with an unprecedented pentacyclic 6/6/6/6/3 skeleton, were isolated from Herpotrichia sp. SF09, an isopod-associated fungus, along with a new shunt product protrichone (3). Their structures were elucidated by the analysis of spectroscopic data, residual dipolar coupling (RDC)-based computer-assisted 3D structure elucidation (CASE-3D), and single-crystal X-ray diffraction in combination with electronic circular dichroism (ECD) calculations. Compounds 1 and 2 were assessed to be potent anti-neuroinflammatory agents in lipopolysaccharide (LPS)-induced BV-2 microglial cells with the half maximal inhibitory concentration (IC50) values of 0.41 and 0.11 µM, respectively.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ascomicetos/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Microglia/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Linhagem Celular , Teoria da Densidade Funcional , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos
19.
World J Clin Cases ; 7(20): 3341-3346, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31667189

RESUMO

BACKGROUND: Hydrofluoric acid (HF) is one of the most common causes of chemical burns. HF burns can cause wounds that deepen and progress aggressively. As a result, HF burns are often severe even if they involve a small area of the skin. Published cases of HF burns have mostly reported small HF burn areas. Few cases of HF inhalation injury have been reported to date. CASE SUMMARY: A 24-year-old man suffered from extensive hydrofluoric acid burns covering 60% of the total body surface area (TBSA), including deep second degree burns on 47% and third degree burns on 13% of the TBSA, after he fell into a pickling pool containing 15% HF. Comprehensive treatments were carried out after the patient was admitted. Ventricular fibrillation occurred 9 times within the first 2 h, and the lowest serum Ca2+ concentration was 0.192 mmol/L. A dose of calcium gluconate (37 g) was intravenously supplied during the first 24 h, and the total amount of calcium gluconate supplementation was 343 g. Extracorporeal membrane oxygenation (ECMO) was applied for 8 d to handle the acute respiratory distress syndrome (ARDS) induced by the HF inhalation injury. The patient was discharged after 99 d of comprehensive treatment, including skin grafting. CONCLUSION: Extensive HF burns combined with an inhalation injury led to a potentially fatal electrolyte imbalance and ARDS. Adequate and timely calcium supplementation and ECMO application were the keys to successful treatment of the patient.

20.
Sci Total Environ ; 691: 848-857, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326808

RESUMO

Microplastics (MPs) have become a global environmental concern because of their ubiquitous presence. While extensive microplastic researches have focused on the marine environment, pervasive MPs contamination in soil and their detrimental impacts have been largely overlooked. Excessive concentrations of MPs and additives have been found in soil derived from the use of plastic mulches and the application of sewage sludge to fields. They may pose directly or indirectly as adverse effects on flora and fauna. The objectives of this review are (1) to summarize the abundance, sources, and properties of MPs in soil; (2) to analyze combined effects of MPs and various other environmental pollutants on soil system; and (3) to discuss the possible risks posed by MPs to soil biodiversity, food safety and human health. This review will highlight key future research areas for scientists and policymakers, and increase overall understanding of soil MPs pollution and its potential environmental impacts.

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