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1.
Plant Dis ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33656362

RESUMO

Jerusalem cherry (Solanum pseudocapsicum), which belongs to the genus Solanum and the family Solanaceae, possesses high ornamental value and is widely cultivated as an indoor ornament due to its bright red berries at maturity (Xu et al., 2018). In September 2019, leaf spot was detected on jerusalem cherry plants in Yuxiu Park, Shizhong district, Jinan, Shandong Province. Field surveys were done in a 1/15 ha park. Disease incidence was estimated at approximately 18% across the survey area. Foliar symptoms began as small white spots. As the disease progressed, lesions expanded and merged, and developed into large irregular white spots, with pale grey edge. At last, lesions were densely distributed throughout the leaves. To isolate the pathogen, twenty leaf tissues (5 × 5 mm) were cut from the border between diseased and healthy tissue, surface disinfected in 75% alcohol for 15 s, soaked in 0.1% mercuric chloride for 1 min, washed with sterile distilled water three times, and cultured on potato dextrose agar (PDA) at 25°C. Nineteen fungal isolates were obtained and were single-spored to obtain pure cultures. The colony of LCL7, a representative isolate, on PDA was initially white to orange, but turned black after 3 to 4 days incubation with black conidial masses. Conidia were single-celled, hyaline, straight, cylindrical, apex obtuse, and ranged from 13.4 to 18.3 × 3.2 to 4.9 µm (n = 50) (Diao et al., 2017). To validate the species identification, rDNA internal transcribed spacer (ITS) region (White et al., 1990), and the partial sequences of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin (ACT), ß-tubulin (TUB2), and chitin synthase (CHS-1) (Damm et al., 2019; He et al., 2019), were amplified and sequenced. The ITS, GAPDH, ACT, TUB2, and CHS-1 sequences of isolate LCL7 were submitted to GenBank (MW221320, MW227217, MW227218, MW227219, and MW266988, respectively). ITS, ACT, TUB2, and CHS-1 BLAST showed 99-100% homology with sequences of Colletotrichum liaoningense (ITS, 100% to MH636504; ACT, 100% to MH622582; TUB2, 99.56% to MH622714, CHS-1, 99.33% to MH622446, respectively), although GAPDH showed 93.98% homology with sequence MH681383 (234/249bp). Neighbor-joining tree based on concatenated sequences of the five genes was constructed using MEGA7.0. The results showed the isolate was closely related to C. liaoningense. Based on morphological and molecular characteristics, the isolate LCL7 was identified as C. liaoningense. Pathogenicity tests were performed by spraying a conidial suspension (1 × 105 conidia/mL) on ten two-year-old healthy jerusalem cherry plants. Ten other plants with sterile water served as controls. All samples were incubated in a growth chamber at 25±2°C and transparent plastic bags to keep relative humidity high for 2 days. All inoculated plants showed symptoms similar to those observed in the field after 21 days, but no disease occurred on control plants. The same fungus was successfully reisolated from inoculated leaves and reidentified based on morphology and molecular characteristics, and the fungus was not isolated from the control plants, thus confirming Koch's postulates. Pathogenicity tests were repeated twice. C. liaoningense can cause anthracnose in chili and mango in China (Diao et al., 2017; Li et al., 2019).To our knowledge, this is the first report of anthracnose on jerusalem cherry caused by C. liaoningense in China, which influences ornamental value and reduces market value. Identification of the causes of the disease will help develop effective strategies for managing this disease.

2.
Nat Commun ; 12(1): 1483, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674611

RESUMO

Acute myocardial infarction is a common condition responsible for heart failure and sudden death. Here, we show that following acute myocardial infarction in mice, CD8+ T lymphocytes are recruited and activated in the ischemic heart tissue and release Granzyme B, leading to cardiomyocyte apoptosis, adverse ventricular remodeling and deterioration of myocardial function. Depletion of CD8+ T lymphocytes decreases apoptosis within the ischemic myocardium, hampers inflammatory response, limits myocardial injury and improves heart function. These effects are recapitulated in mice with Granzyme B-deficient CD8+ T cells. The protective effect of CD8 depletion on heart function is confirmed by using a model of ischemia/reperfusion in pigs. Finally, we reveal that elevated circulating levels of GRANZYME B in patients with acute myocardial infarction predict increased risk of death at 1-year follow-up. Our work unravels a deleterious role of CD8+ T lymphocytes following acute ischemia, and suggests potential therapeutic strategies targeting pathogenic CD8+ T lymphocytes in the setting of acute myocardial infarction.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Granzimas/genética , Granzimas/metabolismo , Coração/fisiopatologia , Remodelação Ventricular/fisiologia , Animais , Apoptose , Linfócitos T CD8-Positivos/patologia , Modelos Animais de Doenças , Feminino , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Proteínas de Homeodomínio/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/metabolismo , Miocárdio/patologia , Suínos , Transcriptoma
3.
Cancer Lett ; 504: 104-115, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33587979

RESUMO

Macrophages, which are highly plastic, can be polarized to M1 or M2 subtypes according to the diverse signals in complex microenvironment. Studies have shown the activation of YAP, an oncogenic transcriptional co-activator, increased macrophage recruitment. However, its role in macrophage polarization remains to be elucidated, especially in triple-negative breast cancer (TNBC) progression. Here we found TNBC cells increased YAP expression in macrophages, which depended on OTUD5-mediated deubiquitination and stabilization of YAP, then the high expression of YAP polarized macrophage to the M2-like phenotype. Moreover, the elevation of YAP in M2-like macrophage promotes the pro-metastatic potential of TNBC cells via MCP-1/CCR2 pathway. We also observed high expression of YAP in M2 macrophage was negatively related to survival. Collectively, our finding suggested the therapeutic strategy that targets YAP+ M2 macrophage could be a novel option for TNBC treatment.

4.
Medicine (Baltimore) ; 100(3): e24356, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33546070

RESUMO

ABSTRACT: To investigate the characteristics of pulmonary artery distensibility (PAD) in patients with acute pulmonary embolism (APE) and to assess the correlation of PAD with APE severity and right ventricular function. A total of 33 patients who underwent retrospective electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) with a definite diagnosis of APE were included in the study. According to APE severity, the patients were divided into severe (SPE) and non-severe (NSPE) groups. Data from a control group without APE matching the basic demographics of the APE patients were collected. Pulmonary artery distensibility (PAD) and right ventricular function parameters were compared among the 3 groups, their relationships were investigated, and receiver operating characteristic (ROC) curves were used to determine the sensitivity and specificity of the above parameters for the diagnosis of APE severity. The PAD values of the control, NSPE, and SPE groups were (7.877 ±â€Š2.637) × 10-3 mm/Hg, (6.050 ±â€Š2.011) × 10-3 mm/Hg, (4.321 ±â€Š1.717) × 10-3 mm/Hg, respectively (P < .01). There were statistically significant differences in right ventricular function parameters among the 3 groups (P < .05). The correlation analysis between PAD and right ventricular function parameters showed a weak negative correlation (r = -0.281--0.392). The area under the ROC curve of PAD was 0.743, the critical value was 4.200, and the sensitivity and specificity were 62.5% and 94.1%, respectively. The PAD obtained by retrospective ECG-gated CTPA could accurately evaluate APE severity and right ventricular function. As the severity of APE increases, PAD decreases, which is helpful to identify patients at high risk of APE.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Artéria Pulmonar/anormalidades , Embolia Pulmonar/fisiopatologia , Função Ventricular Direita/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/patologia , Curva ROC , Estudos Retrospectivos
5.
EMBO Rep ; 22(4): e51023, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33615678

RESUMO

The establishment of bipolar spindles during meiotic divisions ensures faithful chromosome segregation to prevent gamete aneuploidy. We analyzed centriole duplication, as well as centrosome maturation and separation during meiosis I and II using mouse spermatocytes. The first round of centriole duplication occurs during early prophase I, and then, centrosomes mature and begin to separate by the end of prophase I to prime formation of bipolar metaphase I spindles. The second round of centriole duplication occurs at late anaphase I, and subsequently, centrosome separation coordinates bipolar segregation of sister chromatids during meiosis II. Using a germ cell-specific conditional knockout strategy, we show that Polo-like kinase 1 and Aurora A kinase are required for centrosome maturation and separation prior to metaphase I, leading to the formation of bipolar metaphase I spindles. Furthermore, we show that PLK1 is required to block the second round of centriole duplication and maturation until anaphase I. Our findings emphasize the importance of maintaining strict spatiotemporal control of cell cycle kinases during meiosis to ensure proficient centrosome biogenesis and, thus, accurate chromosome segregation during spermatogenesis.

6.
Virus Res ; 295: 198276, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33476694

RESUMO

Oligoadenylate synthetases-like (OASL) protein exerts various effects on DNA and RNA viruses by inhibiting cGAS-mediated IFN production and by enhancing RIG-I-mediated IFN induction, respectively. In this study, we aimed to examine the role of OASL in pseudorabies virus (PRV) proliferation and investigate the function of the PRV UL24 protein in cellular innate immunity. We found that OASL regulates PRV proliferation by enhancing RIG-I signaling. PRV infection decreased the expression of OASL at both the mRNA and protein levels in PK15 and HeLa cells. OASL expression suppressed the proliferation of PRV in a RIG-I-dependent manner and boosted RIG-I-mediated IFN expression as well as IFN-stimulated gene (ISG) induction. In contrast, knockdown of OASL enhanced PRV proliferation and reduced RIG-I signaling. However, the PRV UL24 protein was found to impair RIG-I signaling, thus inhibiting transcription of IFN and ISGs. In addition, the UL24 protein reduced RIG-I-induced expression of endogenous OASL in an IRF3-dependent manner, thereby antagonizing the OASL antiviral effect. Taken together, our findings characterize the role of OASL in PRV proliferation and provide new insights into the role of UL24 in PRV pathogenesis.

7.
Exp Cell Res ; 399(1): 112449, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33347856

RESUMO

Delayed endothelial healing after drug eluting stent (DES) implantation is a critical clinical problem in treatment of coronary artery diseases. Exosomes exhibit proangiogenic potential in a variety of ischemic diseases. However, the association of exosomes with endothelial regeneration after DES implantation has been rarely reported. In this study, we aimed to investigate the therapeutic effects of mesenchymal stem cell (MSC)-derived exosomes on endothelial cells treated with rapamycin and explore the potential mechanisms of MSC-derived exosomes in promoting endothelial regeneration. Exosomes were isolated from MSCs by ultracentrifugation and identified by transmission electron microscopy, nanoparticle tracking analysis, and Western blot assay. The in vitro effects of MSC-derived exosomes on the proliferation and migration of endothelial cells treated with rapamycin were evaluated by integrated experiment, cell counting kit-8, scratch, tube formation, and transwell assays. And the apoptosis of rapamycin-induced endothelial cells loaded with MSC-derived exosomes was detected using TUNEL and Annexin-V FITC and PI double-staining assays. The microRNA (miRNA) cargo of MSC-derived exosomes was identified by high-throughput RNA sequencing. Pro-angiogenic miRNAs and key pathways were further characterized. Our results indicated that MSC-derived exosomes could be ingested into umbilical vein endothelial cells (HUVECs) and significantly enhanced cell proliferation rate, migratory and tube-forming capabilities in vitro. MSC-derived exosomes also inhibited the apoptosis of HUVECs induced by rapamycin. A distinct class of exosomal miRNAs was further identified, including six miRNAs tightly related to neovasculogenesis. Silencing the expression of exosomal miRNA-21-5p and let-7c-5p attenuated the pro-proliferative and pro-migratory capacity of MSC-derived exosomes. Moreover, functional enrichment analysis indicated that metabolic pathways might contribute to reendothelialization. This study highlights a proregenerative effect of MSC-derived exosomes in vitro, which may be partly explained by the delivery of pro-angiogenic miRNAs to endothelial cells.

8.
J Clin Invest ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258804

RESUMO

The triggering receptor expressed on myeloid cells-1 (TREM-1) drives inflammatory responses in several cardiovascular diseases but its role in abdominal aortic aneurysm (AAA) remains unknown. Our objective was to explore the role of TREM-1 in a mouse model of Angiotensin (Ang) II-induced AAA. TREM-1 expression was detected in mouse aortic aneurysm and colocalizes with macrophages. Trem1 gene deletion (Apoe-/-Trem1-/-), as well as TREM-1 pharmacological blockade with LR-12 peptide limited both AAA development and severity. Trem1 gene deletion attenuated the inflammatory response in the aorta, with a reduction of Il1b, Tnfa, Mmp2 and Mmp9 mRNA expression, and led to a decreased macrophage content, due to a reduction of Ly6Chi classical monocyte trafficking. Conversely, antibody-mediated TREM-1 stimulation exacerbated Ly6Chi monocyte aorta infiltration after AngII infusion through CD62L up-regulation and promoted pro-inflammatory signature in the aorta, resulting in worsening AAA severity. AngII infusion stimulated TREM-1 expression and activation on Ly6Chi monocytes through AngII Receptor Type I (AT1R). In human AAA, TREM-1 was detected and TREM1 mRNA expression correlated with SELL mRNA expression. Finally, circulating levels of sTREM-1 were increased in patients with AAA when compared to patients without AAA. In conclusion, TREM-1 is involved in AAA pathophysiology and may represent a promising therapeutic target in human.

10.
Front Vet Sci ; 7: 597843, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33251273

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV), which seriously endangers the world pig industry, invades host cells through receptor-mediated endocytosis involving clathrin. CD163 is an essential receptor for PRRSV during its infection of cells. The scavenger receptor cysteine-rich 5 (SRCR5) domain of the CD163 molecule is necessary for PRRSV infection, and interacts with glycoproteins GP2a and GP4 of PRRSV, allowing the virus to infect the host cells. In this study, a monoclonal antibody (mAb) against the SRCR5-6 region of porcine CD163 was developed, and the target epitope of the mAb was determined as 497TWGTVCDSDF506, which is directly adjacent to the ligand-binding pocket (LBP) domain (487-495aa) of CD163. Further study indicated that the mAb could partially block PRRSV infection of its target cells, pulmonary alveolar macrophages. The mAb developed in the study may provide a foundation of antiviral therapy for PRRSV.

11.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(10): 1174-1177, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33198858

RESUMO

OBJECTIVE: To analyze the clinical characteristics and prognosis of coronavirus disease 2019 (COVID-19) patients complicated with pneumothorax. METHODS: The clinical data of 7 COVID-19 patients complicated with pneumothorax admitted to Huanggang Central Hospital from January 3 to March 10, 2020 were retrospectively analyzed. The clinical features, diagnosis and treatment were summarized, and experience in the treatment of COVID-19 was shared. RESULTS: (1) General information: among the 7 patients, 5 were males and 2 were females. Four of them had no underlying disease, and 1 had a history of diabetes and hypertension. One patient had only a history of hypertension. There were 6 cases of right pneumothorax and 1 case of bilateral pneumothorax. The 7 patients had a long hospital stay, all over 4 weeks, mostly complicated with multiple organ dysfunction. (2) Imaging examination: 1 case evolved from the early stage to the advanced stage within 1 week and to the severe stage within 2 weeks. Pneumothorax occurred 4 weeks later, and was absorbed within 2 weeks. The remaining 6 patients presented progressive stage on admission, all of them advanced to severe stage within 1 to 2 weeks, and most of them presented diffused consolidation shadows, striation shadows and fibrosis of both lungs, obvious pleural adhesion, and extremely slow lesion absorption. (3) Treatment: 1 severe patient with pneumothorax 4 weeks after onset was given non-invasive mechanical ventilation. The remaining 6 critically ill patients were treated with endotracheal intubation and mechanical ventilation. Five patients were treated with mechanical ventilation within 3 days after the occurrence of pneumothorax, and 1 patient was treated with mechanical ventilation after 11 days. (4) Outcome: 1 patient without endotracheal intubation was continuously given nasal high-flow oxygen therapy, and the condition was stable. Four of the 6 patients complicated with pneumothorax after endotracheal intubation died, and the other 2 patients successfully removed the drainage tube within 2 weeks of closed thoracic drainage, and their condition gradually stabilized. CONCLUSIONS: COVID-19 complicated with pneumothorax is a dangerous disease with poor prognosis, and should be paid adequate attention.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Pneumotórax , Infecções por Coronavirus/complicações , Feminino , Humanos , Masculino , Pneumonia Viral/complicações , Pneumotórax/etiologia , Estudos Retrospectivos
12.
Mol Med Rep ; 22(6): 4485-4491, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33173966

RESUMO

In December 2019, an emergence of pneumonia was detected in patients infected with a novel coronavirus (CoV) in Wuhan (Hubei, China). The International Committee on Taxonomy of Viruses named the virus severe acute respiratory syndrome­CoV­2 and the disease CoV disease­19 (COVID­19). Patients with COVID­19 present with symptoms associated with respiratory system dysfunction and hematological changes, including lymphopenia, thrombocytopenia and coagulation disorders. However, to the best of our knowledge, the pathogenesis of COVID­19 remains unclear. Therefore, understanding the mechanisms underlying the hematological changes that manifest during COVID­19 may aid in the development of treatments and may improve patient prognosis.


Assuntos
Betacoronavirus , Infecções por Coronavirus/sangue , Pneumonia Viral/sangue , Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/imunologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/imunologia , Microambiente Celular , Infecções por Coronavirus/complicações , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Síndrome da Liberação de Citocina/sangue , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/prevenção & controle , Citocinas/sangue , Testes Diagnósticos de Rotina , Endotélio Vascular/patologia , Testes Hematológicos , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Hipoalbuminemia/etiologia , Fígado/fisiopatologia , Pulmão/fisiopatologia , Linfopenia/etiologia , Linfopenia/fisiopatologia , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/terapia , Traumatismo por Reperfusão/etiologia , Trombocitopenia/etiologia , Trombocitopenia/fisiopatologia , Trombofilia/etiologia
14.
Vaccine ; 38(50): 7956-7962, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33131934

RESUMO

Classical swine fever virus (CSFV) and Porcine reproductive and respiratory syndrome virus (PRRSV) are both important pathogens which seriously harm the economic swine industry worldwide. We have previously demonstrated that rPRRSV-E2 is a promising live, virus-vectored vaccine that provides 100% protection against highly pathogenic PRRSV (HP-PRRSV) and CSFV. Here, we evaluated the duration of immunity (DOI) of the vaccine strain, rPRRSV-E2. Vaccine or cell culture medium was administered to piglets at 4 weeks of age. All immunized piglets developed high levels of antibodies, which could maintain for up to 23 weeks, against PRRSV and CSFV. All immunized pigs were well protected from the challenge of HP-PRRSV or CSFV at 20 weeks and 24 weeks post vaccination. The vaccine protection rate was still 100% at 24 weeks after immunization. The immune efficacy results showed that the immune duration of rPRRSV-E2 could be up to 5 months.

15.
J Cell Mol Med ; 24(21): 12777-12788, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32954646

RESUMO

Long noncoding RNAs (lncRNAs) have been suggested to play indispensable roles in multiple heart diseases. However, the correlations between lncRNAs and atrial fibrillation (AF) are unclear. In this study, we performed comprehensive lncRNA profiling via high-throughput RNA sequencing analysis using non-AF and AF rabbit models. Based on a series of filtering pipelines and bioinformatics analyses, TCONS-00106987 was selected for further research. TCONS-00106987 levels were increased in the atria during AF. Moreover, the atrial effective refractory period was shortened and the AF inducibility was increased in vivo in response to lentiviral-mediated up-regulation of TCONS-00106987. TCONS-00106987 repression resulted in the opposite effects. Further studies indicated that TCONS-00106987 expression was positively correlated with the expression of the protein-coding gene KCNJ2. Luciferase reporter assays and whole-cell patch-clamp recording confirmed that TCONS-00106987 promoted electrical remodelling via endogenous competition with microRNA-26 (miR-26) to induce transcription of its target gene KCNJ2, thereby increasing inward-rectifier K+ current (IK1 ). In conclusion, our study reveals a pathogenic lncRNA-miRNA regulatory network specific to atrial electrical remodelling that offers potential therapeutic targets for AF.

16.
Cell Cycle ; 19(20): 2589-2599, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32975478

RESUMO

Basal-like triple-negative breast cancers frequently express high levels of c-Myc. This oncoprotein signals to the core cell cycle machinery by impinging on cyclin E. High levels of E-type cyclins (E1 and E2) are often seen in human triple-negative breast tumors. In the current study, we examined the requirement for E-type cyclins in the c-Myc-driven mouse model of breast cancer (MMTV-c-Myc mice). To do so, we crossed cyclin E1- (E1-/-) and E2- (E2-/-) deficient mice with MMTV-c-Myc animals, and observed the resulting cyclin E1-/-/MMTV-c-Myc and cyclin E2-/-/MMTV-c-Myc females for breast cancer incidence. We found that mice lacking cyclins E1 or E2 developed breast cancers like their cyclin Ewild-type counterparts. In contrast, further reduction of the dosage of E-cyclins in cyclin E1-/-E2+/-/MMTV-c-Myc and cyclin E1+/-E2-/-/MMTV-c-Myc animals significantly decreased the incidence of mammary carcinomas, revealing arole for E-cyclins in tumor initiation. We also observed that depletion of E-cyclins in human triple-negative breast cancer cell lines halted cell cycle progression, indicating that E-cyclins are essential for tumor cell proliferation. In contrast, we found that the catalytic partner of E-cyclins, the cyclin-dependent kinase 2 (CDK2), is dispensable for the proliferation of these cells. These results indicate that E-cyclins, but not CDK2, play essential and rate-limiting roles in driving the proliferation of c-Myc overexpressing breast cancer cells.

17.
Food Funct ; 11(9): 7415-7420, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966484

RESUMO

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread around the world at an unprecedented rate. In the present study, 4 marine sulfated polysaccharides were screened for their inhibitory activity against SARS-CoV-2, including sea cucumber sulfated polysaccharide (SCSP), fucoidan from brown algae, iota-carrageenan from red algae, and chondroitin sulfate C from sharks (CS). Of them, SCSP, fucoidan, and carrageenan showed significant antiviral activities at concentrations of 3.90-500 µg mL-1. SCSP exhibited the strongest inhibitory activity with IC50 of 9.10 µg mL-1. Furthermore, a test using pseudotype virus with S glycoprotein confirmed that SCSP could bind to the S glycoprotein to prevent SARS-CoV-2 host cell entry. The three antiviral polysaccharides could be employed to treat and prevent COVID-19.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Feófitas/química , Polissacarídeos/farmacologia , Rodófitas/química , Pepinos-do-Mar/química , Animais , Antivirais/química , Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Humanos , Pandemias , Pneumonia Viral/virologia , Polissacarídeos/química , Tubarões , Sulfatos/química , Internalização do Vírus/efeitos dos fármacos
18.
Vet Microbiol ; 248: 108833, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32891948

RESUMO

Currently live attenuated porcine reproductive and respiratory syndrome (PRRS) and classical swine fever (CSF) vaccines are widely used in Chinese swine herds. However, the mutual effects of vaccination procedures and severe stress caused by successive vaccinations harm piglets and make it difficult to stimulate robust and effective immune responses. In our previous study, a recombinant PRRS virus (PRRSV) vectored vaccine candidate rPRRSV-E2, which expresses CSF virus (CSFV) E2 protein, has been demonstrated being able to protect piglets against lethal challenge of highly-pathogenic (HP)-PRRSV and CSFV. In this study, we determine whether preexisting maternally derived antibodies (MDA) interfere with the immune efficacy of rPRRSV-E2. 8 experimental groups of piglets, with or without PRRSV MDAs or CSFV MDAs were immunized with a single dose of 105 TCID50 rPRRSV-E2 or DMEM and challenged with HP-PRRSV or CSFV. Clinical characteristics, PRRSV- or CSFV-specific antibodies, viremia and pathological changes were monitored, examined and analyzed. The results showed that rPRRSV-E2-vaccinated piglets, either with or without MDAs directed against PRRSV or CSFV were completely protected from the lethal challenge of HP-PRRSV or CSFV. These results demonstrate that the MDAs do not interfere with the immune efficacy of rPRRSV-E2, which indicates that rPRRSV-E2 could have great significance in the effective prevention and control of HP-PRRSV and CSFV.

19.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(8): 1134-1140, 2020 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895184

RESUMO

OBJECTIVE: To explore whether thrombopoietin (TPO) can rescue megakaryopoiesis by protecting bone marrowderived endothelial progenitor cells (BM-EPCs) in patients receiving chemotherapy for hematological malignancies. METHODS: Bone marrow samples were collected from 23 patients with hematological malignancies 30 days after chemotherapy and from 10 healthy volunteers. BM-EPCs isolated from the samples were identified by staining for CD34, CD309 and CD133, and their proliferation in response to treatment with TPO was assessed using CCK8 assay. DiL-Ac-LDL uptake and FITC-UEA-I binding assay were performed to evaluate the amount of BM-EPCs from the subjects. Tube-formation and migration experiments were used for functional assessment of the BM-EPCs. The BM-EPCs with or without TPO treatment were co-cultured with human megakaryocytes, and the proliferation of the megakaryocytes was detected with flow cytometry. RESULTS: Flow cytometry indicated that the TPO-treated cells had high expressions of CD34, CD133, and CD309. CCK8 assay demonstrated that TPO treatment enhanced the proliferation of the BM-EPCs, and the optimal concentration of TPO was 100 µg/L. Double immunofluorescence assay indicated that the number of BM-EPC was significantly higher in TPO-treated group than in the control group. The TPO-treated BM-EPCs exhibited stronger tube-formation and migration abilities (P < 0.05) and more significantly enhanced the proliferation of co-cultured human megakaryocytes than the control cells (P < 0.05). CONCLUSIONS: TPO can directly stimulate megakaryopoiesis and reduce hemorrhage via protecting the function of BM-EPCs in patients following chemotherapy for hematological malignancies.


Assuntos
Medula Óssea , Neoplasias Hematológicas , Células da Medula Óssea , Células Cultivadas , Humanos , Megacariócitos , Trombopoetina
20.
Chem Commun (Camb) ; 56(78): 11637-11640, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870197

RESUMO

Histidine can trigger bimetallic gold/copper nanoclusters to turn on strong red fluoresence, which is capable of sensing nanomolar levels of histidine selectively.

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