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1.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.

2.
Toxins (Basel) ; 12(11)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33138205

RESUMO

Indoxyl sulfate (IS), a uremic toxin, causes chronic kidney disease (CKD) progression via its tubulotoxicity. After cellular uptake, IS directly induces apoptotic and necrotic cell death of tubular cells. Additionally, IS increases oxidative stress and decreases antioxidant capacity, which are associated with tubulointerstitial injury. Injured tubular cells are a major source of transforming growth factor-ß1 (TGF-ß1), which induces myofibroblast transition from residual renal cells in damaged kidney, recruits inflammatory cells and thereby promotes extracellular matrix deposition in renal fibrosis. Moreover, IS upregulates signal transducers and activators of transcription 3 phosphorylation, followed by increases in TGF-ß1, monocyte chemotactic protein-1 and α-smooth muscle actin production, which participate in interstitial inflammation, renal fibrosis and, consequently, CKD progression. Clinically, higher serum IS levels are independently associated with renal function decline and predict all-cause mortality in CKD. The poor removal of serum IS in conventional hemodialysis is also significantly associated with all-cause mortality and heart failure incidence in end-stage renal disease patients. Scavenging the IS precursor by AST-120 can markedly reduce tubular IS staining that attenuates renal tubular injury, ameliorates IS-induced oxidative stress and rescues antioxidant glutathione activity in tubular epithelial cells, thereby providing a protective role against tubular injury and ultimately retarding renal function decline.

3.
Eur J Pharmacol ; : 173703, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33159935

RESUMO

Obesity is closely linked with type 2 diabetes and the effective therapies on obesity-associated diabetes are under development. The aim of this study was undertaken to investigate whether the inhibition of the augmented CCR5-mediated signaling could be a common target for treatment of obesity-associated insulin resistance and impairment of pancreatic insulin secretion in high-fat diet (HFD) fed rats and CCR5 knockout mice and also in isolated islets and RIN-m5F cells. Conducted with SD rats, HFD-induced body weight gain was significantly decreased in those combined with Maraviroc treatment, but food intake remained similar compared to control. Maraviroc also significantly improved the impaired oral glucose tolerance test (OGTT). As compared with wild-type mice, CCR5 deletion significantly attenuated the HFD-induced increases in glucose area under curve of OGTT and the value of HOMA-IR as well as plasma lipid profile. It also reversed the HFD-suppressed gene expressions of GLUT4 and IRS-1 in adipose tissue. On the other hand, the HFD-associated islet macrophage and T-cell infiltration were significantly decreased in CCR5 KO mice. H2O2 significantly suppressed glucose-stimulated insulin secretion (GSIS) is isolated islets, which were significantly reversed in those cotreated with CCR5 mAb. H2O2 failed to change GSIS in those of CCR5 KO mice. The palmitate-induced reactive oxygen species production was significantly decreased in those cotreated with CCR5 antagonist in RIN-m5F cells. Collectively, it is suggested that targeting inhibition of the CCR5 mediated inflammatory pathway could not only improve obesity-associated insulin resistance but also directly alleviate pancreatic ß-cell dysfunction.

4.
Int J Mol Sci ; 21(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198315

RESUMO

Vascular calcification (VC) is a critical contributor to the rising cardiovascular risk among at-risk populations such as those with diabetes or renal failure. The pathogenesis of VC involves an uprising of oxidative stress, for which antioxidants can be theoretically effective. However, astaxanthin, a potent antioxidant, has not been tested before for the purpose of managing VC. To answer this question, we tested the efficacy of astaxanthin against VC using the high phosphate (HP)-induced vascular smooth muscle cell (VSMC) calcification model. RNAs from treated groups underwent Affymetrix microarray screening, with intra-group consistency and inter-group differential expressions identified. Candidate hub genes were selected, followed by validation in experimental models and functional characterization. We showed that HP induced progressive calcification among treated VSMCs, while astaxanthin dose-responsively and time-dependently ameliorated calcification severities. Transcriptomic profiling revealed that 3491 genes exhibited significant early changes during VC progression, among which 26 potential hub genes were selected based on closeness ranking and biologic plausibility. SOD2 was validated in the VSMC model, shown to drive the deactivation of cellular senescence and enhance antioxidative defenses. Astaxanthin did not alter intracellular reactive oxygen species (ROS) levels without HP, but significantly lowered ROS production in HP-treated VSMCs. SOD2 knockdown prominently abolished the anti-calcification effect of astaxanthin on HP-treated VSMCs, lending support to our findings. In conclusion, we demonstrated for the first time that astaxanthin could be a potential candidate treatment for VC, through inducing the up-regulation of SOD2 early during calcification progression and potentially suppressing vascular senescence.

5.
J Vasc Access ; : 1129729820961955, 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33012250

RESUMO

BACKGROUND: Angioplasty-related vessel rupture is a common complication of interventions. The effect of covered stents to treat venous rupture has been evaluated in smaller series, but should be further evaluated. OBJECTIVE: To report the immediate outcomes and patency rates of a covered stent to rescue angioplasty-related venous rupture of hemodialysis vascular access. METHODS: From January 2013 to December 2018, 113 procedures complicated with vessel ruptures were retrospectively analyzed from a prospectively collected database of 8146 hemodialysis access interventions. The strategies to salvage vessel ruptures were based on the discretion of the treating physicians. Follow-up outcomes were obtained via review of the angiographic images, procedural notes, and medical and dialysis records within 12 months after the index procedures. RESULTS: A total of 52 vessel ruptures (21 fistulas, 31 grafts) salvaged by using Viabahn covered stents were enrolled. Vessel ruptures developed in 28 (53.8%) thrombectomy procedures. Device success was achieved in all procedures (100%) and clinical success was achieved in 50 (96.2%). The primary patency of the stent area was 66.0% at 6 months and 50.0% at 12 months. The primary patency of the entire access circuit was 27.4% at 6 months and 16.0% at 12 months. The most common cause of access circuit primary patency loss was thrombotic occlusion for graft accesses and restenosis at stent area for native accesses. Eleven vascular accesses were abandoned within 12 months after vessel ruptures, and the secondary patency rate of the entire access circuit was 78.0% at 12 months. CONCLUSIONS: Treatment of angioplasty-induced vessel rupture of hemodialysis vascular accesses by using Viabahn covered stents has good immediate outcomes and patency results at the stent area. Nonetheless, the patency rate of entire access circuit was still below the threshold recommended by guidelines.

6.
Adv Mater ; : e2005353, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33043512

RESUMO

Power consumption is one of the most challenging bottlenecks for complementary metal-oxide-semiconductor integration. Negative-capacitance field-effect transistors (NC-FETs) offer a promising platform to break the thermionic limit defined by the Boltzmann tyranny and architect energy-efficient devices. However, it is a great challenge to achieving ultralow-subthreshold-swing (SS) (10 mV dec-1 ) and small-hysteresis NC-FETs simultaneously at room temperature, which has only been reported using the hafnium zirconium oxide system. Here, based on a ferroelectric LiNbO3 thin film with great spontaneous polarization, an ultralow-SS NC-FET with small hysteresis is designed. The LiNbO3 NC-FET platform exhibits a record-low SS of 4.97 mV dec-1 with great repeatability due to the superior capacitance matching characteristic as evidenced by the negative differential resistance phenomenon. By modulating the structure and operating parameters (such as channel length (Lch ), drain-sourse bias (Vds ), and gate bias (Vg )) of devices, an optimized SS from ≈40 to ≈10 mV dec-1 and hysteresis from ≈900 to ≈60 mV are achieved simultaneously. The results provide a new potential method for future highly integrated electronic and optical integrated energy-efficient devices.

7.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(4): 431-437, 2020 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-32865364

RESUMO

Oral cancer is the most common malignant tumor in the head and neck, and is one of the world's top ten malignancies. Microbial infection is an important risk factor of oral cancer. Candida albicans is the most popular opportunistic fungal pathogen. Epidemiological studies have shown that Candida albicans is closely tied to oral malignancy. Animal experimentation have also proven that infection of Candida albicans can promote the development of oral epithelial carcinogenesis. The current studies have revealed several mechanisms involved in this process, including destroying the epithelial barrier, producing carcinogenic substances (nitrosamines, acetaldehyde), inducing chronic inflammation, activating immune response, etc. However, current researches on mechanisms are still inadequate, and some hypotheses remain controversial. Here, we review the findings related to Candida albicans' effect on the malignant transformation of oral mucosa, hoping to provide reference for deep research and controlling oral cancer clinically.


Assuntos
Doenças da Boca , Neoplasias Bucais , Animais , Candida albicans , Carcinogênese , Mucosa Bucal
8.
Cell Commun Signal ; 18(1): 153, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948206

RESUMO

BACKGROUND: Rabies virus (RABV) is reported to encode five phosphoproteins (P), which are involved in viral genomic replication, axonal transport, oxidative stress, interferon antagonism, and autophagy induction. However, the functions of the different P proteins are poorly understood. METHODS: Immunofluorescence staining and western blot were performed to detect the autophagy activity, the form of ring-like structure, and the colocalization of BECN1 and P. Co-immunoprecipitation was performed to detect the interaction between P and BECN1. QRT-PCR and TCID50 assay were performed to detect the replication level of RABV. Small interfering RNA was used to detect the autophagy signaling pathway. RESULTS: We found that P5 attaches to N-terminal residues 1-139 of BECN1 (beclin1) on the BECN1 ring-like structure through amino acid residues 173-222 of P5. Subsequently, we found that P5-induced autophagosomes did not fuse with lysosomes. Becn1 silencing did not recover P5 overexpression-induced promotion of RABV replication. Mechanistically, RABV protein PΔN82 (P5) induced incomplete autophagy via the BECN1-mediated signaling pathway. CONCLUSIONS: Our data indicate that P5 binding to the BECN1 ring benefits RABV replication by inducing BECN1 signaling pathway-dependent incomplete autophagy, which provides a potential target for antiviral drugs against RABV. Video abstract.

9.
Asia Pac J Clin Nutr ; 29(3): 593-602, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32990620

RESUMO

BACKGROUND AND OBJECTIVES: The high mortality rate of H7N9 strain of avian influenza virus (AIV) infected patients has been a major clinical concern. Iron overload increases the susceptibility of host for several kinds of microbial infection. However, the study on patients' iron and ferritin status associated with clinical outcome of AIVH7N9 virus infection is poorly understood, and in order to explain the linkage we carried out this study. METHODS AND STUDY DESIGN: We retrospectively collected serum from 46 patients infected with H7N9 virus from the hospital in Hangzhou city, Zhejiang province of China in 2013. We measured the level of serum iron and ferritin by Enzyme-Linked Immunosorbent Assay (ELISA). The correlation analysis of iron and ferritin with disease severity was done by SPSS 16.0 and MedCalc Software. RESULTS: After H7N9 infection, there is a reduction in iron level and an increase in ferritin, hepcidin and C-reactive protein (CRP) level in patient's serum compared to those of the control (p<0.001), and there's little correlation between procalcitonin (PCT) level and H7N9 infection. At week 1 and week 2 post-infection, serum iron level is much lower and ferritin level is much higher in the patients who died later than those in the patients who survived. The sensitivity, specificity, and Area Under the Curve (AUC) of the assay was calculated with MedCalc software and they were 85.5%, 65.9% and 0.803 for iron and 84.9%, 80.7% and 0.900 for ferritin, 95.2%, 51.1% and 0.684 for PCT and 100%, 94.6% and 0.988 for CRP, respectively. CONCLUSIONS: Our study found that low serum iron and high serum ferritin levels are correlated with the disease severity of H7N9-infected patients and can predict fatal outcomes.

10.
J Am Heart Assoc ; 9(18): e016084, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32865101

RESUMO

Background Patients with rheumatoid arthritis are at twice the risk of ventricular arrhythmia and sudden cardiac death as the general population. We hypothesize that ß-blocker treatment of rheumatoid arthritis is antiarrhythmic by producing synergistic anticatecholaminergic and anti-inflammatory effects. Methods and Results Collagen-induced arthritis (CIA) was induced in Lewis rats by immunization with type II collagen in Freund's incomplete adjuvant. The treatment with propranolol (4 mg/kg) started on the first day of immunization. We evaluated the ventricular vulnerability to ventricular arrhythmia using in vivo programmed stimulation and performed ex vivo optical mapping to measure the electrical remodeling of the heart. The ventricular tissue was further processed for immunohistochemical staining and protein array analysis. The assessment of ventricular vulnerability showed that the number and duration of the induced ventricular arrhythmia episodes were increased in CIA rats, which were improved with propranolol treatment. The sympathovagal index and the plasma level of catecholamines significantly increased in CIA rats, whereas the use of propranolol attenuated sympathetic hyperactivity. In the optical mapping study, electrical remodeling, characterized by prolonged action potential duration, slow conduction velocity, and steepened action-potential duration restitution, were noted in CIA rats and reversed in the propranolol-treatment group. The propranolol treatment was associated with decreases in paw thickness, fewer inflammatory cell infiltrations in the heart, reduced levels of cardiac inflammatory cytokines, and less cardiac fibrosis as compared with the CIA group. Conclusions CIA increased ventricular arrhythmia vulnerability through sympathetic hyperinnervation and proarrhythmic ventricular electrophysiological remodeling. Treatment with propranolol in CIA rats was both anti-inflammatory and antiarrhythmic.

11.
J Formos Med Assoc ; 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32919876

RESUMO

BACKGROUND/PURPOSE: Malignant hyperthermia (MH) is a life-threatening pharmacogenetic disease with only two known causative genes, RYR1 and CACNA1S. Both are huge genes containing numerous exons, and they reportedly only account for 50-70% of known MH patients. Next-generation sequencing (NGS) technology and bioinformatics could help delineate the genetic diagnosis of MH and several MH-like clinical presentations. METHODS: We established a capture-based targeted NGS sequencing framework to examine the whole genomic regions of RYR1, CACNA1S and the 16.6 Kb mitochondrial genome, as well as 12 other genes related to excitation-contraction coupling and/or skeletal muscle calcium homeostasis. We applied bioinformatics analyses to the variants identified in this study and also to the 48 documented RYR1 pathogenic variants. RESULTS: The causative variants were identified in seven of the eight (87.5%) MH families, but in none of the 10 individuals classified as either normal controls (N = 2) or patients displaying MH-like clinical features later found to be caused by other etiologies (N = 8). We showed that RYR1 c.1565A>G (p.Tyr522Cys)(rs118192162) could be a genetic hot spot in the Taiwanese population. Bioinformatics analyses demonstrated low population frequencies and predicted damaging effects from all known pathogenic RYR1 variants. We estimated that more than one in 1149 individuals worldwide carry MH pathogenic variants at RYR1. CONCLUSION: NGS and bioinformatics are sensitive and specific tools to examine RYR1 and CACNA1S for the genetic diagnosis of MH. Pathogenic variants in RYR1 can be found in the majority of MH patients in Taiwan.

12.
J Texture Stud ; 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32984954

RESUMO

A technology called sandwich-type sheeting was used to produce noodles with potato flakes. The technical parameters of sheeting were first optimized. Then the processing and eating qualities of potato noodles made with sandwich-type sheeting and conventional sheeting were compared. Results showed that the optimal moisture of inner-layer dough and outer-layer dough was 41 and 37%, respectively. The suitable ratio of the thickness of inner layer to that of outer layer was 3:1. The tensile strength of the sandwich-type dough sheet was 1.285 times higher than that of conventional dough sheet. The cooking loss of the sandwich-type noodles was 37.0% lower than that of conventional noodles, and the adhesiveness decreased by 51.0%. In the sandwich-type noodles, the compact gluten network structure of outer wheat layer prevented the leaching of soluble substances in the inner layer added with potato flakes, improving the cooking and eating qualities of potato noodles.

13.
Ecotoxicol Environ Saf ; 206: 111203, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32866888

RESUMO

Degradation of the prothioconazole by three strains of microorganisms isolated from activated sludge obtained from a pesticide factory was assessed, and an ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QqTOF-MS) method for the determination of prothioconazole and its metabolites was established. The optimal conditions for the degradation of prothioconazole were determined by single factor optimization experiments. A degradation rate of 93.32% is achieved when the prothioconazole is co-cultured with the strain W313 at a cultivation time of 60 h, a cultivation temperature of 30 °C, a pH of 6.33, a prothioconazole concentration of 50 mg L-1, a microorganism volume of 10%, and a dextrose volume of 4%. The three effective microorganism strains were identified by morphological and molecular biology to be Candida tropicalis, Enterobacter cloacae, and Pseudomonas aeruginosa. UPLC-QqTOF-MS analysis allowed the identification of 62 different prothioconazole degradation products produced by the strain cultures, with prothioconazole-desthio, prothioconazole-dechloropropyl, and oxidizing prothioconazole being the main products. In addition, degradation products from different strains and conditions were compared. The results of scatter plot (S-Plot) analysis indicated that C9H7NO, C10H17N7, and C12H13ClN2O were only detected in the products incubated with Enterobacter cloacae. Thus, this study demonstrates that Enterobacter cloacae and Pseudomonas aeruginosa possesses high potential for bioremediation of prothioconazole-contaminated environments.

14.
Int J Cancer ; 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32781482

RESUMO

Human papillomavirus (HPV) is the well-established etiologic factor for cervical neoplasia. Cervical conization constitutes an effective treatment for high-grade cervical intraepithelial neoplasia (HG-CIN). We conducted an observational study for long-term outcomes and HPV genotype changes after conization for HG-CIN. Between 2008 and 2014, patients with newly diagnosed HG-CIN before conization (surveillance new [SN] group) and those who had undergone conization without hysterectomy (surveillance previous [SP] group) were enrolled. HPV testing and Pap smear were performed periodically for the SN and SP (collectively S) groups. All other patients receiving conization for HG-CIN during the study period were identified from our hospital database. Those eligible but not enrolled into our study were assigned to the non-surveillance (non-S) group. For the S group (n = 493), the median follow-up period was 74.3 months. Eighty-four cases had recurrent CIN Grade 2 or worse (CIN2+) (5-year cumulative rate: 14.8%), of which six had invasive cancer. Among the 84 patients, 65 (77.4%) exhibited type-specific persistence in the paired HPV results, whereas only 7 (8.3%) harbored new HPV types that belonged to the 9-valent vaccine types. Among the 7397 non-S patients, 789 demonstrated recurrent CIN2+, of which 57 had invasive cancer. The stages distribution of those progressed to invasive cancer in the non-S group were more advanced than the S group (P = .033). Active surveillance might reduce the severity of those progressed to cancer. Because a majority of the patients with recurrent CIN2+ had persistent type-specific HPV infections, effective therapeutic vaccines are an unmet medical need.

15.
16.
Pest Manag Sci ; 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32816378

RESUMO

BACKGROUND: Mythimna separata is a devastating agricultural pest that has recently developed insecticide resistance. Integument-specific cytochrome P450s were reported to participate in cuticle formation and could be potential targets for pesticide synthesis. RESULTS: The transcriptome of integuments of M. separata larvae was constructed, generating a total of 38 058 unigenes with an average length of 1243 bp. These unigenes are enriched in functional categories such as lipid transport and metabolism, and secondary metabolites biosynthesis, transport and catabolism. Amongst unigenes, cytochrome P450s were identified and 66 unique P450s with complete open reading frames were named. These P450s were divided into 17 families and 32 subfamilies, containing conserved motifs such as helix C, helix I, helix K, and the heme-binding region. RNA-Seq and RT-qPCR analyses showed different expression levels of P450s in integuments of M. separata larvae. Further RT-qPCR analysis of P450s among different tissues showed that five P450s, especially CYP4G199, were specifically highly expressed in integuments. Moreover, knockdown of CYP4G199 disturbed cuticle formation, leading to imperfection in larval cuticle, and prevented pupation of M. separata. CONCLUSION: Transcriptome of larval integuments provided sequence and expression of genes in M. separata. CYP4G199 is specifically highly expressed in larval integuments and is important for cuticle formation in M. separata.

17.
Mol Pharm ; 17(9): 3461-3476, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32787276

RESUMO

Due to the cell affinity of chitosan (CS) and the hydrophilicity of polyethylene oxide (PEO), CS/PEO composited nanofiber meshes (NFMs) have been extensively used as wound healing dressings for skin tissue regeneration. Nonetheless, numerous innate drawbacks of the NFM system such as the use of toxic spinning solvents and cross-linkers, moderate water regain capacity, and lack of triggered release function significantly hampered their biomedical applications. In order to enhance their performances in promoting cell growth and preventing bacterial infection, highly swelling cross-linked N-maleoyl-functional chitosan (MCS)/PEO NFMs have been developed as the next-generation CS/PEO NFM system through an acid-free electrospinning process and a UV-irradiated cross-linked treatment without the use of aldehyde-containing cross-linkers. With the simultaneous introduction of ethylene oxide chains and disulfide bonds in the cross-linkages, this new NFM system displays enhanced swelling capability, antibacterial ability, triggered antibiotic release, and high biocompatibility. These biomedical merits enable the new NFM systems to be utilized as tissue scaffolds, especially for functional wound healing dressings.

18.
Appl Microbiol Biotechnol ; 104(19): 8427-8437, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32813067

RESUMO

Infectious bronchitis virus (IBV) is a member of genus gamma-coronavirus in the family Coronaviridae, causing serious economic losses to the poultry industry. Reverse genetics is a common technique to study the biological characteristics of viruses. So far, there is no BAC reverse genetic system available for rescue of IBV infectious clone. In the present study, a new strategy for the construction of IBV infectious cDNA clone was established. The full-length genomic cDNA of IBV vaccine strain H120 was constructed in pBAC vector from four IBV fragment subcloning vectors by homologous recombination, which contained the CMV promoter at the 5' end and the hepatitis D virus ribozyme (HDVR) sequence and bovine growth hormone polyadenylation (BGH) sequence after the polyA tail at the 3' end of the full-length cDNA. Subsequently, using the same technique, another plasmid pBAC-H120/SCS1 was also constructed, in which S1 gene from IBV H120 strain was replaced with that of a virulent SC021202 strain. Recombinant virus rH120 and rH120/SCS1 were rescued by transfecting the plasmids into BHK cells and passaged in embryonated chicken eggs. Finally, the pathogenicity of both the recombinant virus strains rH120 and rH120/SCS1 was evaluated in SPF chickens. The results showed that the chimeric rH120/SCS1 strain was not pathogenic compared with the wild-type IBV SC021202 strain and the chickens inoculated with rH120/SCS1 could resist challenge infection by IBV SC021202. Taken together, our results indicate that BAC reverse genetic system could be used to rescue IBV in vitro and IBV S1 protein alone might not be the key factor for IBV pathogenicity. KEY POINTS: • BAC vector was used to construct IBV full-length cDNA by homologous recombination. • Based on four subcloning vectors, a recombinant chimeric IBV H120/SCS1 was constructed and rescued. • Pathogenicity of H120/SCS1 was similar to that of H120, but different to that of SC021202.


Assuntos
Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/patogenicidade , Proteínas Virais/genética , Animais , Embrião de Galinha , Galinhas , Infecções por Coronavirus/veterinária , DNA Complementar , Recombinação Homóloga , Doenças das Aves Domésticas/virologia , Proteínas Recombinantes/genética , Vacinas Virais/genética , Vacinas Virais/imunologia , Virulência/genética
19.
Front Microbiol ; 11: 1630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765462

RESUMO

Although infectious bronchitis virus (IBV) is the first coronavirus identified, little is known about which membrane protein of host cells could interact with IBV spike protein and facilitate the infection by the virus. In this study, by using a monoclonal antibody to the S1 protein of IBV M41 strain, we found that heat shock protein member 8 (HSPA8) could interact with spike protein of IBV. HSPA8 was found to be present on the cell membrane and chicken tissues, with highest expression level in the kidney. Results of co-IP and GST-pull-down assays indicated that the receptor binding domain (RBD) of IBV M41 could interact with HSPA8. The results of binding blocking assay and infection inhibition assay showed that recombinant protein HSPA8 and antibody to HSPA8 could inhibit IBV M41 infection of chicken embryonic kidney (CEK) cells. Further, we found that HSPA8 interacted with the N-terminal 19-272 amino acids of S1 of IBV Beaudette, H120 and QX strains and HSPA8 from human and pig also interacted with IBV M41-RBD. Finally the results of binding blocking assay and infection inhibition assay showed that recombinant HSPA8 protein and antibody to HSPA8 could inhibit IBV Beaudette strain infection of Vero cells that were treated with heparanase to remove heparan sulfate from the cell surface. Taken together, our results indicate that HSPA8 is a novel host factor involved in IBV infection.

20.
Huan Jing Ke Xue ; 41(3): 1393-1400, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608641

RESUMO

Using a 150 L moving bed biofilm reactor (MBBR), with the temperature controlled at 28℃ and high NH4+-N concentration (average concentration 350 mg·L-1), inorganic wastewater was used as an influent to start the completely autotrophic nitrogen removal over nitrite (CANON) process. Meanwhile, the flocculent sludge was taken into a 5 L sequencing batch reactor, and the influent NH4+-N concentration was maintained at 90-200 mg·L-1 for the recovery of short-cut nitrification. The results showed that in the MBBR reactor, when the average hydraulic retention time (HRT) was 12 h, short-cut nitrification and total nitrogen (TN) removal rate were mutually constrained, the average TN removal rate was 38.2%, and the average δNO3--N/TN value was 0.274; when the HRT dropped to 6 h, the δNO3--N/TN value decreased from 0.347 to 0.146. The sequencing batch reactor (SBR) maintained aeration and anoxic time for 30 min and 20 min, respectively, by intermittent aeration, while the dissolved oxygen concentration during the aerobic process was 0.5 mg·L-1 to 0.6 mg·L-1, the free nitrous acid concentration was higher than 0.18 mg·L-1 at the end of each cycle, NAR increased from 0 to 99.2% after 12 days, NUR decreased to 0 from an initial 24.8 mg·(g·h)-1, and the TN removal rate decreased from 13% to 3%; the system successfully converted to short-range nitrification. High-throughput sequencing results showed that the abundance of Candidatus Kuenenia in the flocculent sludge and biofilm in the MBBR reactor were 7.91% and 17.38% respectively, Nitrosomonas accounted for 27.43% and 2.55%, respectively, while Nitrospira accounted for 0.30% and 0.28%, respectively. After the recovery of short-cut nitrification in the SBR, the abundance of ammonia-oxidizing bacteria and anaerobic ammonia oxidation decreased to 1.18% and 0.01%, respectively, and the abundance of Nitrospira increased to 1.39%.

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