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1.
J Neurosci Methods ; 367: 109438, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896102

RESUMO

BACKGROUND: The evaluation of structural changes after stroke has made great progress; however, it remains difficult to evaluate functional neural changes. NEW METHOD: Here, we report a novel imaging technique that could monitor delayed functional neural circuit injury in an animal model of cerebral ischemia-reperfusion. The changes in 50 mM glutamate-induced biophotonic activities in functional neural circuits in rat brain slices after middle cerebral artery occlusion were investigated with an ultraweak biophoton imaging system. RESULTS: Six hours after ischemia-reperfusion, the rats presented a significant decrease in motion ability together with a large part of the unstained 2,3,5-Triphenyltetrazolium chloride (TTC) area in the ischemia-reperfusion side, whereas the intensity of the biophoton emissions was consistent on both the ischemia-reperfusion and non-ischemic sides of brain slices. Twenty-four hours after reperfusion, the behavior evaluation and TTC staining recovered slightly, and the intensity of the biophoton emissions was weaker on the ischemia-reperfusion side than on the contralateral side. One week after reperfusion, the behavioral test and TTC staining recovered to normal levels; however, the intensity of the biophoton emissions was decreased significantly on both the ischemia-reperfusion and contralateral sides, and such changes were even distinguished in different brain areas, such as the sensory and motor coteries and striatum. CONCLUSION: These findings suggest that delayed functional neural circuit injury induced by cerebral ischemia-reperfusion could be identified with biophoton imaging techniques, providing a novel functional evaluation method for animal models of cerebral ischemia-reperfusion.

2.
Front Microbiol ; 12: 739348, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956111

RESUMO

Palygorskite (Pal), a clay nanoparticle, has been demonstrated to be a vehicle for drug delivery. Copper has antibacterial properties, and zinc is an essential micronutrient for intestinal health in animals and humans. However, whether copper/zinc-modified Pal (Cu/Zn-Pal) can protect chickens from Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) infection remains unclear. In this study, three complexes (Cu/Zn-Pal-1, Cu/Zn-Pal-2, and Cu/Zn-Pal-3) were prepared, and Cu/Zn-Pal-1 was shown to be the most effective at inhibiting the growth of S. Typhimurium in vitro, whereas natural Pal alone had no inhibitory effect. In vivo, Cu/Zn-Pal-1 reduced S. Typhimurium colonization in the intestine of infected chickens and relieved S. Typhimurium-induced organ and intestinal mucosal barrier damage. Moreover, this reduction in Salmonella load attenuated intestinal inflammation and the oxidative stress response in challenged chickens. Additionally, Cu/Zn-Pal-1 modulated the intestinal microbiota in infected chickens, which was characterized by the reduced abundance of Firmicutes and the increased abundance of Proteobacteria and Bacteroidetes. Our results indicated that the Cu/Zn-Pal-1 complex may be an effective feed supplement for reducing S. Typhimurium colonization of the gut.

3.
Int J Biometeorol ; 65(11): 1919-1927, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34050434

RESUMO

Previous studies indicate that the incidence of bacillary dysentery is closely related to meteorological factors. However, the impact of temperature and the spatial heterogeneity of the disease in regions of unbalanced socioeconomic development remains unclear. Therefore, this research collected data for 29,639 daily bacillary dysentery cases in children under 5 years of age, as well as the meteorological variables from China's Beijing-Tianjin-Hebei region, to analyze the spatial pattern of bacillary dysentery and reveal its nonlinear association with temperature. The SatScan method was employed first, to detect the spatial heterogeneity of the disease risk, and then the distributed lag nonlinear model (DLNM) was used to analyze the relationships between the daily minimum, mean, and maximum temperatures and bacillary dysentery in the stratified heterogeneous regions. The results indicated that bacillary dysentery incidence presented statistically significant spatial heterogeneity. The area of highest risk was found to be Beijing and its neighboring regions, which have high population densities. There was also a positive association between bacillary dysentery and temperature. Hotter temperatures were accompanied by higher relative risks. In the most likely spatial cluster region, the excess risk (ER) values for a 1°C rise in minimum, mean, and maximum temperatures above the median were 4.65%, 11.30%, and 19.21%, respectively. The effect of temperature on bacillary dysentery peaked at a lag of 3 to 4 days. The findings of this study will aid risk assessments and early warning systems for bacillary dysentery.


Assuntos
Disenteria Bacilar , Pequim , Criança , Pré-Escolar , China/epidemiologia , Disenteria Bacilar/epidemiologia , Humanos , Medição de Risco , Temperatura
4.
Water Res ; 196: 116990, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33725645

RESUMO

Noroviruses (NoVs) are the leading cause of acute gastroenteritis (AGE) outbreaks. Since 2014, novel genetic variants of NoV have been continuously identified and have caused a sharp increase in the number of AGE outbreaks. The specific geographical distribution and expanding genetic diversity of NoV has posed a challenge to conventional surveillance. Here, we describe the long-term dynamic correlation between NoV distribution in sewage and in the local population through the molecular surveillance of NoV in Guangdong, 2013-2018. The relative viral loads of the GI and GII genotypes in sewage were calculated through RT-PCR. A high-throughput sequencing method and operational taxonomic unit (OTU) clustering pipeline were developed to illustrate the abundances of different genotypes and genetic variants in sewage. Our results showed that the NoV viral loads and the emergence of new variants in sewage were closely associated with NoV outbreak risks in the population. Compared with the outbreaks surveillance, the dominance of the newly emerged variants, GII.P17-GII.17 and GII.P16-GII.2, could be detected one or two months ahead in sewage of a hub city. In addition, the dynamics of pre-epidemic variants, which were rarely detected in clinics, could be captured through sewage surveillance, thus improving our understanding of the origin and evolution of these novel epidemic variants. Our data highlight that sewage surveillance could provide nearly real-time and high-throughput data on NoV circulation in the community. With the advances in sequencing techniques, the sewage surveillance system could also be extended to other related infectious diseases.


Assuntos
Infecções por Caliciviridae , Norovirus , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Cidades , Surtos de Doenças , Genótipo , Humanos , Norovirus/genética , Filogenia , Esgotos
5.
ACS Omega ; 6(4): 2990-2998, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33553917

RESUMO

In oil and gas production in deep-water high-pressure-high-temperature (HP-HT) wells, wellhead uplift may cause the seal failure of wellbore integrity. Aiming at the oil and gas production stage in deep-water HP-HT wells, we considered the influence of cement sheath cementation and developed a model for calculating the height of wellhead uplifts, and simulation experiments for wellhead uplifts were carried out under the condition of the double pipe string at different cement return heights and multilayer pipe string coupling cementing and noncementing based on a self-developed HP-HT wellhead uplift simulation device. The results show that the elongation of the double pipe string under the condition of a cement return height of 100% is reduced significantly compared with that under the condition of a cement return height of 50%. Also, the maximum elongation of the multilayer pipe string under the condition of coupling and cementing is significantly reduced compared with that under the condition of noncementing. These show that cement sealing has a binding effect on wellhead uplifts. The error between the calculated and the experimental results is less than 10%; thus, the model can be used to predict the wellhead uplift height under different working conditions and provide technical guidance for designing scientific measures to prevent wellhead uplifts.

6.
Bioengineered ; 12(1): 266-277, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33356788

RESUMO

Chitosan hydrolysis by chitosanase is one of the most effective methods to produce chitosan oligosaccharides. One of the prerequisites of enzyme fermentation production is to select and breed enzyme-producing cells with good performance. So in the process of fermentation production, the low yield of chitosanase cannot meet the current requirement. In this paper, a strain producing chitosanase was screened and identified, and a novel mutagenesis system (Atmospheric and Room Temperature Plasma (ARTP)) was selected to increase the yield of chitosanase. Then, the fermentation medium was optimized to further improve the enzyme activity of the strain. A strain of Bacillus cereus capable of producing chitosanase was screened and identified from soil samples. A mutant strain of B.cereus was obtained by Atmospheric and Room Temperature Plasma mutagenesis and bioscreening method, and chitosanase activity was 2.49 folds that of the original bacterium. After an optimized fermentation medium, the enzyme activity of the mutant strain was 1.47 folds that of the original bacterium. Combined with all the above optimization experiments, the enzyme activity of mutant strain increased by 3.66 times. The results showed that the Atmospheric and Room Temperature Plasma mutagenesis and bioscreening method could significantly increase the yield of chitosanase in B.cereus, and had little effect on the properties of the enzyme. These findings have potential applications in the mutagenesis of other enzyme-producing microorganisms.


Assuntos
Bacillus cereus , Proteínas de Bactérias , Glicosídeo Hidrolases , Mutagênese/genética , Bacillus cereus/enzimologia , Bacillus cereus/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura , Estabilidade Enzimática , Fermentação , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Engenharia de Proteínas , Microbiologia do Solo
7.
Int J Biol Macromol ; 169: 18-27, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33309671

RESUMO

Fumonisins have posed hazardous threat to human and animal health worldwide. Enzymatic degradation is a desirable detoxification approach but is severely hindered by serious shortage of detoxification enzymes. After mining enzymes by bioinformatics analysis, a novel carboxylesterase FumDSB from Sphingomonadales bacterium was expressed in Escherichia coli, and confirmed to catalyze fumonisin B1 to produce hydrolyzed fumonisin B1 by liquid chromatography mass spectrometry for the first time. FumDSB showed high sequence novelty, sharing only ~34% sequence identity with three reported fumonisin detoxification carboxylesterases. Besides, FumDSB displayed its high degrading activity at 30-40 °C within a broad pH range from 6.0 to 9.0, which is perfectly suitable to be used in animal physiological condition. It also exhibited excellent pH stability and moderate thermostability. This study provides a FB1 detoxification carboxylesterase which could be further used as a potential food and feed additive.


Assuntos
Carboxilesterase/química , Fumonisinas/química , Alphaproteobacteria/metabolismo , Animais , Carboxilesterase/isolamento & purificação , Carboxilesterase/metabolismo , Hidrolases de Éster Carboxílico/química , Cromatografia Líquida , Fumonisinas/análise , Fumonisinas/metabolismo , Humanos , Espectrometria de Massas , Sphingomonadaceae/enzimologia
8.
Fish Shellfish Immunol ; 107(Pt B): 547-555, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33161091

RESUMO

Tripartite motif (TRIM) family proteins are named by the presence of tripartite motifs in their amino terminal domains. Apart from the amino terminal, their carboxyl terminal contain variable domains which mediate diverse functions of the TRIM proteins. It had been found that TRIM proteins played important roles in distinct biological processes, such as innate immunity, anti-tumor immunity, cell cycle regulation and so on. In the present study, we cloned a TRIM32 (LvTRIM32) gene from Litopenaeus vannamei. LvTRIM32 was highly expressed in hemocytes, gills and epidermis, and subcellular localization analysis indicated that it was widely distributed in S2 cells. In vitro ubiquitination assays indicated that LvTRIM32 had E3 ubiquitin ligase activity. Results of real-time RT-PCR assay showed that LvTRIM32 was induced in shrimp hemocytes upon oxidative stress. It was also proved that the promoter activity of LvTRIM32 was enhanced by NF-E2-related factor, and knocked-down expression of LvTRIM32 depressed the expression of malic enzyme and epoxide hydrolase. Downregulated LvTRIM32 suppressed the cumulative mortality of shrimp under oxidative stress. Moreover, it was found that LvTRIM32 could be induced in shrimp hemocytes upon immunostimulation, and downregulated LvTRIM32 increased the cumulative mortality of shrimp infected with white spot syndrome virus (WSSV) or Vibrio alginolyticus. Collecting results suggested that LvTRIM32 was a member of shrimp antioxidant stress system, and it was also involved in WSSV- or V. alginolyticus-infection resistance.


Assuntos
Proteínas de Artrópodes/genética , Imunidade Inata/genética , Estresse Oxidativo/genética , Penaeidae/genética , Penaeidae/imunologia , Proteínas com Motivo Tripartido/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/metabolismo , Perfilação da Expressão Gênica , Hemócitos/imunologia , Proteínas com Motivo Tripartido/imunologia , Proteínas com Motivo Tripartido/metabolismo
9.
Cell Metab ; 31(6): 1068-1077.e3, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32369736

RESUMO

Type 2 diabetes (T2D) is a major comorbidity of COVID-19. However, the impact of blood glucose (BG) control on the degree of required medical interventions and on mortality in patients with COVID-19 and T2D remains uncertain. Thus, we performed a retrospective, multi-centered study of 7,337 cases of COVID-19 in Hubei Province, China, among which 952 had pre-existing T2D. We found that subjects with T2D required more medical interventions and had a significantly higher mortality (7.8% versus 2.7%; adjusted hazard ratio [HR], 1.49) and multiple organ injury than the non-diabetic individuals. Further, we found that well-controlled BG (glycemic variability within 3.9 to 10.0 mmol/L) was associated with markedly lower mortality compared to individuals with poorly controlled BG (upper limit of glycemic variability exceeding 10.0 mmol/L) (adjusted HR, 0.14) during hospitalization. These findings provide clinical evidence correlating improved glycemic control with better outcomes in patients with COVID-19 and pre-existing T2D.


Assuntos
Glicemia/análise , Infecções por Coronavirus/mortalidade , Diabetes Mellitus Tipo 2/sangue , Índice Glicêmico/fisiologia , Hiperglicemia/sangue , Pneumonia Viral/mortalidade , Idoso , Betacoronavirus/patogenicidade , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/patologia , Diabetes Mellitus Tipo 2/complicações , Suscetibilidade a Doenças/patologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Hiperglicemia/complicações , Hipoglicemiantes/uso terapêutico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/complicações , Insuficiência de Múltiplos Órgãos/mortalidade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/patologia , Estudos Retrospectivos , SARS-CoV-2
10.
Environ Sci Pollut Res Int ; 27(18): 22708-22719, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32319067

RESUMO

In this paper, a total of 62,712 aquatic product samples were collected from 32 provinces of China during 2015-2017. By analyzing the spatial distributions and non-parametric tests of five heavy metals (lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr), and arsenic (As)) in four aquatic product (fish (n = 44,353), shrimp (n = 8453), crab (n = 5367), and shellfish (n = 4539)), it was found that the concentrations of the five heavy metals in the same aquatic product are significantly different in different regions. Furthermore, we calculated daily estimated intake (EDI) of each of the five heavy metals and assessed non-cancer risk and cancer risk using target hazard quotient (THQ) and target cancer risk (TR), respectively. The results showed that for mean exposure levels, the THQ values in four aquatic products were all below one, meaning that there was no non-carcinogenic risk. For high exposure levels, the hazard index (HI) value exceeded one in fish in North China, which means the potential non-carcinogenic risk should not be ignored. As for cadmium, most of the TR values in crab and shellfish exceed 1 × 10-4 in North China, East China, and South China. For chromium, except for Northeast China, the TR values in fish in other regions exceed 1 × 10-4; it indicated that the cancer risk caused by cadmium or chromium should not be ignored.


Assuntos
Arsênio , Metais Pesados/análise , Animais , China , Monitoramento Ambiental , Contaminação de Alimentos/análise , Medição de Risco
11.
J Ethnopharmacol ; 251: 112503, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-31891798

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Conyza blinii H.Lév. is a type of natural plant distributed in southwest of China. Its dried overground section can be used in traditional Chinese medicine (TCM) for treating infections, inflammations and occasionally cancers. CBS (Conyza blinii saponin), mainly composed of triterpenoidal saponins of Conyza blinii H.Lév. CBS is considered as the major active fraction of this species. The current investigation have focused on the mechanisms of CBS with regard to its anti-cancer activity. Hence it is of high relevance of identifying the anti-cancer efficacy of ethnomedicine. AIM OF THE STUDY: To understand the anti-cancer mechanism of CBS using both in vitro and in vivo experiments. MATERIALS AND METHODS: CBS (Conyza blinii saponin) was obtained as described previously. We tested the anti-cancer activity of CBS using in vitro HeLa cell models and in vivo animal models. We adopted immunoblot, RT-PCR (reverse transcription polymerase chain reaction), luciferase reporter assay and flow cytometry to study relevant proteins, genes, pathways and cellular ROS (reactive oxygen species) responsible for anti-cancer activity of CBS. More, 24 tumour-xenografted mice were grouped randomly as 'control', 'cisplatin' (as positive control), 'low dose' and 'high dose' groups. The IL-1ß, TNF-α, PGE2 and IL-2 in the blood serum and the tumour tissue of mice were measured. RESULTS AND CONCLUSIONS: We have found that CBS is capable of inducing apoptotic cancer cell death via both caspase-dependent and -independent pathways. CBS inhibits the activation of TGF-ß signaling pathway in a dose- and time-dependent manner. Phospho-ERK, phospho-JNK and phospho-p38 MAPK are significantly suppressed by CBS. Furthermore, some inflammation mediators including IL-1ß, TNF-α and PGE2 from animal samples were found decreased in CBS-treated mice models. In contrast, the level of IL-2, a cytokine commonly used for treating cancers, increased reversely. Last, we have discovered that CBS is able to decrease the expression of Nrf2, inhibit the activation of ARE and increase ROS level in HeLa cells. In summary, we have confirmed that the anti-cancer activity of CBS is possibly related to its TGF-ß, MAPK, Nrf2 signaling pathways as well as some cancer related inflammation mediators and cytokines.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Conyza , Saponinas/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Feminino , Células HeLa , Humanos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
12.
Bio Protoc ; 10(13): e3672, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33659342

RESUMO

Short-chain fatty acids (SCFAs), which are formed mainly by bacteria fermenting undigested carbohydrates in the colon, they are based on the number of carbon atoms in the carbon chain. Organic fatty acids with less than 6 carbon atoms are called short-chain fatty acids. SCFAs are closely related to various aspects of the human body, so more and more researchers concentrate on SCFAs. This protocol describes, a direct injection gas chromatography detection method with a pretreatment method for extracting SCFA from mice feces by combining acidification. The corresponding sample limit of quantization (LOQ) and limit of detection (LOD) are 0.8-1.0 mg/L and 0.5-0.8 mg/L, respectively. The correlation coefficient of calibration curve is greater than 0.999. The recovery rate of the spiked standard is 80%-102%. This method can be used to analyze and determine SCFAs in mice feces. Therefore, this is an economical, effective and reproducible method for SCFAs measurement in mice samples.

13.
Fish Shellfish Immunol ; 93: 977-985, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31449979

RESUMO

C-type lectins (CTLs), which bind carbohydrates in a Ca2+-dependent manner, are involved in many cellular activities, especially immunity. CTLs play important roles in both the antibacterial and the antiviral immune response and are also associated with autoimmunity. Several CTLs have been investigated in crustaceans, primarily with respect to their function in the immune response. In this study, we cloned a novel CTL gene (LvCTLU) from Litopenaeus vannamei. LvCTLU is involved in microbe agglutination and phagocytosis. Downregulating LvCTLU increased the cumulative mortality of L. vannamei after Vibrio parahemolyticus infection. Similar to other reported CTLs, LvCTLU also had antiviral properties. Downregulation of LvCTLU also increased the cumulative mortality of L. vannamei after infection with white spot syndrome virus. More importantly, LvCTLU expression was induced by the unfolded protein response (UPR), which is the key pathway in the endoplasmic reticulum (ER)-stress response of eukaryotic organism. Our results suggested that this protein might be involved in the shrimp ER-stress response. Reporter gene assay indicated that LvCTLU was regulated by X-box-binding protein 1, which is the key transcription factor in the UPR. Our study thus revealed that LvCTLU plays vital roles in both the anti-pathogen immune response and the ER-stress response.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Penaeidae/genética , Penaeidae/imunologia , Proteína 1 de Ligação a X-Box/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Lectinas Tipo C/química , Filogenia , Alinhamento de Sequência , Vírus da Síndrome da Mancha Branca 1/fisiologia , Proteína 1 de Ligação a X-Box/metabolismo
14.
Fish Shellfish Immunol ; 84: 404-413, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30316944

RESUMO

Matrix metalloproteinases (MMPs) contribute to both normal and pathological tissue remodeling. They act as regulatory molecules by working in enzyme cascades as well as processing matrix proteins, cytokines, growth factors and adhesion molecules to generate fragments with biological effects. So MMPs could play distrinct roles in the process of pathogen infection. In present study, we cloned a MMP-2 (LvMMP-2) gene from Litopenaeus vannamei. LvMMP-2, highly expressed in epidermis, located to endoplasmic reticulum in S2 cells. Results of real-time RT-PCR assay showed that LvMMP-2 was induced in shrimp hemocytes upon unfolded protein response or oxidative stress, but not via heat shock treatment. It is proved that the promoter activity of LvMMP-2 was enhanced by NF-E2-related factor 2 and AP-1 factor c-Jun. Further research showed that down-regulated LvMMP-2 contributing to oxidative stress injury, could reduce the cumulative mortality of shrimps under oxidative stress. Besides, our study also indicated that LvMMP-2 was accelerated by lipopolysaccharides injection. LvMMP-2 in S2 could increase the promoter activity of several antimicrobial peptide genes, and knocked-down expression of LvMMP-2 depressed the expression of penaeidin2 and ß-Defensin. Moreover, we showed that down-regulated LvMMP-2 suppressed the cumulative mortality of shrimp infected with white spot syndrome virus (WSSV) or with Vibrio alginolyticus. Collecting results suggested that LvMMP-2 involves in shrimp innate immune response, and also contributes to tissue injury caused by WSSV infection.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/imunologia , Penaeidae/genética , Penaeidae/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Metaloproteinase 2 da Matriz/química , Filogenia , Alinhamento de Sequência , Vibrio alginolyticus/fisiologia , Vírus da Síndrome da Mancha Branca 1/fisiologia
15.
Fish Shellfish Immunol ; 84: 541-550, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30366090

RESUMO

Shrimp in culture ponds are challenged by various pathogens as well as harsh water environment. The innate immune system and environmental stress response system of shrimp paly an important role in shrimp survival and growth. For remission the endoplasmic reticulum (ER)-stress caused by environmental stress, unfolded protein response (UPR) may reduce the synthesis of most proteins, including great mass of immune factors, which could weaken the immune function of shrimp. Therefore, how cells keep appropriate amount of immune factor synthesis under such a situation is critical important for shrimp health and growth. In this study, we cloned a new Crustin gene (LvCruU) from Litopenaeus vannamei. We showed that LvCruU has antibacterial activity, and reducing its expression would increase the cumulative mortality of L. vannamei upon the Vibrio parahemolyticus infection. In addition, we found that promoter activity of LvCruU was enhanced not only by the deformed epidermal autoregulatory factor-1 (Deaf1), but also by activating transcription factor 3 (LvATF3) of shrimp UPR. Real-time RT-PCR showed that LvCruU and LvATF3 both were induced upon UPR activation. And moreover, in Thapsigargin plus dsLvCruU injection test, we showed that down-regulation of LvCruU increased the cumulative mortality of V. parahemolyticus-infected shrimp under ER-stress. These results suggest that LvCruU work as a downstream effector of UPR, and contribute to antimicrobic immune response upon ER-stress in L. vannamei.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Filogenia , Staphylococcus aureus/fisiologia , Vibrio parahaemolyticus/fisiologia
16.
J Mol Model ; 24(6): 124, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29721750

RESUMO

The mechanism for the hydroxyl-radical-induced depolymerization of cellulose under alkaline conditions in air was investigated using density functional theory at the B3LYP/6-31+G(d,p) level as well as electron transfer theory. The pathway for the depolymerization of cellulose was obtained theoretically and H abstraction from the C(3) atom of the pyran ring during the cleavage of the glucosidic bond was found to be the rate-limiting step due to its high energy barrier (16.81 kcal/mol) and low reaction rate constant (4.623 × 104 mol L-1 s-1). Calculations of the electron transfer between O2 and the saccharide radical performed with the HARLEM software package revealed that following the H abstraction, the oxygen molecule approaches C(2) on the saccharide radical and obtains an electron from the radical, even though no bond forms between the oxygen molecule and the radical. The rate constant for electron transfer could be as high as 1.572 × 1011 s-1. Furthermore, an enol intermediate is obtained during the final stage of the depolymerization.

17.
Sci Total Environ ; 615: 412-421, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28988077

RESUMO

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) consisting of non-ortho and mono-ortho PCBs are suggested to be very hazardous and have adverse effects on human health. However, their levels and congener profiles in retail foods marketed in Guangdong Province of China have not been elucidated thus far. Thus, in this study, 226 individual samples of beef, freshwater fish, and pork marketed across four regions of Guangdong Province were randomly collected during 2013-2015 to determine their levels of PCDD/Fs and DL-PCBs. The results showed that the total toxic equivalency quantities (TEQs) of most samples were below the maximum limits except for the 26 samples collected from the vicinities of pollution areas. The median total TEQs of these three categories were 0.174, 0.488, and 0.113pgTEQ/g fw, respectively, which indicated that the contamination status of the studied foods was not serious. For congener profiles, significantly different patterns were observed in three food groups, but with the same major TEQ contributors being 2,3,4,7,8-PeCDF in beef, freshwater fish, and pork. Regional differences of congener profiles in each food group were also found in this study, which might be attributed to the regionally different distributions of PCDD/Fs and DL-PCBs in environment media. The dietary exposures of four population subgroups (girls, boys, male adults, and female adults) to PCDD/Fs and DL-PCBs via three food groups were estimated to assessed the potential risks. They were all lower than the provisional tolerable monthly intake (PTMI, 70pgTEQ/kgbw/month) established by Joint FAO/WHO Expert Committee on Food Additive. In these food categories, the exposure to PCDD/Fs and DL-PCBs via freshwater fish was the highest one, which accounted for about 20% of PTMI, indicating that it was the major route to expose dioxin compounds.


Assuntos
Dibenzofuranos Policlorados/análise , Exposição Dietética , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Adolescente , Adulto , Idoso , Animais , Bovinos , Criança , China , Feminino , Peixes , Contaminação de Alimentos , Água Doce , Humanos , Masculino , Pessoa de Meia-Idade , Carne Vermelha , Suínos , Adulto Jovem
18.
Fish Shellfish Immunol ; 70: 129-139, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28882789

RESUMO

A previous study found that inositol-requiring enzyme-1-X-box binding protein 1 (IRE1-XBP1) pathway and the protein kinase RNA (PKR)-like ER kinase-eIF2α (PERK-eIF2α) pathway of shrimp play roles in the unfolded protein response (UPR). And they also be proved that was involved in white spot symptom virus (WSSV) infection. Yet the functions of the third branch in shrimp UPR are still unclear. In this study, we showed that upon UPR activation, activating transcription factor 6 alpha (LvATF6α) of Litopenaeus vannamei was cleaved and transferred from the cytoplasm to the nucleus in 293T cells, indicating that the ATF6 pathway in shrimp is also a branch of UPR. Furthermore, LvATF6α could reduce the apoptosis rate of Drosophila Schneider 2 (S2) cells treated with actinomycin, and knock-down expression of LvATF6α increased the apoptosis rate of shrimp hemocytes. In vivo testing revealed that the short from LvATF6α (LvATF6α-s) was obviously increased after UPR activation or WSSV infection, indicating that the ATF6 pathway was activated in L. vannamei gills under such circumstances. Moreover, knock-down expression of LvATF6α could reduce the cumulative mortality and WSSV copy number in WSSV-infected shrimp. Further study revealed that WSSV may profit from shrimp ATF6 pathway activation in two aspects. First, LvATF6α-s significantly upregulated the expression of the WSSV genes (wsv023, wsv045, wsv083, wsv129, wsv222, wsv249, and wsv343). Second, LvATF6α-s inhibited apoptosis by negatively regulating the apoptosis signal-regulating kinase 1 - (c-Jun N-terminal kinase) pathway. All of these evidences suggested that the ATF6 pathway is a member of the L. vannamei UPR, and it is also engaged in WSSV infection.


Assuntos
Fator 6 Ativador da Transcrição/genética , Proteínas de Artrópodes/genética , Imunidade Inata , Penaeidae/genética , Penaeidae/imunologia , Resposta a Proteínas não Dobradas/fisiologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Fator 6 Ativador da Transcrição/química , Fator 6 Ativador da Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Células Cultivadas , Drosophila melanogaster , Retículo Endoplasmático/fisiologia , Células HEK293 , Humanos , Estresse Fisiológico
19.
J Sep Sci ; 39(18): 3558-63, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27461842

RESUMO

Methyl methanesulfonate and ethyl methanesulfonate are potential genotoxic impurities in imatinib mesylate. In this work, a simple, sensitive, reliable, and fast gas chromatography with mass spectrometry method for the simultaneous determination of methyl methanesulfonate and ethyl methanesulfonate was developed and validated. Total analysis time was only 7 min. An n-hexane/water solution was used to dissolve samples, and then extracted-ion-chromatogram mode was used to quantify methyl methanesulfonate and ethyl methanesulfonate. Calibration curves showed good linearity over the studied range for methyl methanesulfonate and ethyl methanesulfonate. The correlation coefficient of fit exceeded 0.999 for each impurity. The LOD and LOQ of methyl methanesulfonate and ethyl methanesulfonate were as low as 0.001 and 0.005 µg/mL, respectively, with RSDs of the peak area within 1.06-1.96%. Method accuracy was within 97.2-99.8% for methyl methanesulfonate and ethyl methanesulfonate. Therefore, this method can be used to quantify methyl methanesulfonate and ethyl methanesulfonate impurities at extremely low levels in imatinib mesylate.


Assuntos
Contaminação de Medicamentos , Metanossulfonato de Etila/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mesilato de Imatinib/análise , Metanossulfonato de Metila/análise , Mutagênicos/análise , Contaminação de Medicamentos/prevenção & controle
20.
J Sep Sci ; 38(4): 576-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25521967

RESUMO

In this paper, a heart-cutting two-dimensional high-performance liquid chromatography coupled with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was established for controlling the quality of different batches of Hypericum ascyron extract for the first time. In comparison with the common one-dimensional fingerprint, the second-dimensional fingerprint compiled additional spectral data and was hence more informative. The quality of H. ascyron extract was further evaluated by similarity measures and the same results were achieved, the correlation coefficients of the similarity of ten batches of H. ascyron extract were >0.99. Furthermore, we also evaluated the quality of the ten batches of H. ascyron extract by antibacterial activity. The result demonstrated that the quality of the ten batches of H. ascyron extract was not significantly different by MTT. Finally, we demonstrated that the second-dimensional fingerprint coupled with the MTT method was a more powerful tool to characterize the quality of samples of batch to batch. Therefore the proposed method could be used to comprehensively conduct the quality control of traditional Chinese medicines.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Colorimetria/métodos , Medicamentos de Ervas Chinesas/química , Hypericum/química , Colorimetria/instrumentação , Medicamentos de Ervas Chinesas/normas , Controle de Qualidade
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