Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Thorac Dis ; 15(1): 22-32, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36794141

RESUMO

Background: Influenza virus infection complicated by secondary bacterial pneumonia contributes significantly to death during seasonal or pandemic influenza. Secondary infection of Pseudomonas aeruginosa (P. aeruginosa) in influenza virus-infected patients contributes to morbidity and mortality. Methods: Mice were first infected with PR8 influenza virus, followed by a secondary infection of P. aeruginosa. Body weights and survival rate of mice was monitored daily over 20 days. Bronchoalveolar lavage fluids (BALFs) and lung homogenates were harvested for measuring bacterial titers. Lung tissue section slides were stained with hematoxylin and eosin for microscopic observation. After vaccination with inactivated P. aeruginosa cells or recombinant PcrV protein, the mice were subjected to PR8 influenza virus infection followed by a secondary infection of a P. aeruginosa. The inhibition against P. aeruginosa of serum was evaluated by detecting the growth of P. aeruginosa in broth containing diluted sera. Results: The prior influenza infection greatly enhanced the susceptibility to secondary infection of P. aeruginosa and increased morbidity and mortality in mice. Active immunization with inactivated P. aeruginosa cells could protect mice from secondary P. aeruginosa challenge in influenza virus infected mice. Conclusions: To develop an effective P. aeruginosa vaccine might be a promising strategy to decrease the threat of secondary P. aeruginosa infection in influenza patients.

3.
Front Plant Sci ; 13: 848524, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574077

RESUMO

Reasonable water and light management technology can improve economic benefits, coffee yield, and quality. We used cluster analysis and principal component analysis to evaluate and optimize the water and light management technology with high coffee yield, quality, and economic benefits in a subtropical monsoon climate region of China. The experiment was arranged in a randomized complete block design with two factors (3 irrigation levels × 4 shade cultivation treatments) replicated four times during 2016-2017. The irrigation levels consisted of full irrigation (FI) and two deficit irrigations (DI L : 75% FI, DI S : 50% FI). The shade cultivation treatments consisted of no shade cultivation (S0) and three shade cultivation modes (S L : intercropping with four lines of coffee and one line of banana; S M : intercropping with three lines of coffee and one line of banana; S S : intercropping with two lines of coffee and one line of banana). The results showed that the effects of irrigation level and shade cultivation mode on growth, crop yield, most of the photosynthetic characteristics, and nutritional quality were significant (p < 0.05). Regression analysis showed that the leaf radiation use efficiency (RUE) showed a significant negative exponential relation or logistic-curve variation with photosynthetically active radiation (PAR). The bean yield increased with an increase of the shade degree when water was seriously deficient, whereas it first increased and then decreased with an increase of the shade degree under FI and DI L . Based on both cluster analysis and principal component analysis, the FIS S treatment resulted in the highest comprehensive quality of coffee, followed by the FIS M treatment; the DI S S0 treatment obtained the lowest quality. Compared with the FIS0 treatment, the FIS M treatment increased the 2-year average bean yield and net income by 15.0 and 28.5%, respectively, whereas the FIS S treatment decreased these by 17.8 and 8.7%, respectively. To summarize, FIS S treatment significantly improved the nutritional quality of coffee, and FIS M treatment significantly increased the dry bean yield and economic benefits of coffee. The results of the study could provide a theoretical basis for water-saving irrigation and shade cultivation management of coffee in a subtropical monsoon climate region of China.

4.
Front Plant Sci ; 13: 853546, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35449894

RESUMO

The purpose of this study was to know the controlling effects of water and nitrogen coupling on the yield, quality, and water-nitrogen utilization effectiveness of mountain apples under surge-root irrigation in the Loess Plateau. In order to optimize the water and nitrogen irrigation systems of superior quality and high yield, 7 years was selected for the mountain apple test material. The trial was designed with four tiers of irrigation, i.e., full irrigation (FI: 85-100% θ f , where θ f is the field capacity), light deficit irrigation (DIL: 70-85% θ f ), moderate deficit irrigation (DIM: 55-70% θ f ), and severe deficit irrigation (DIS: 40-55% θ f ) and three tiers of nitrogen, i.e., high nitrogen (NH: 600 kg ha-1), medium nitrogen (NM: 400 kg ha-1), and low nitrogen (NL: 200 kg ha-1). The subjective weight attained by the analytic hierarchy methods and the objective weight achieved by the enhanced coefficient of variation method were examined to find the comprehensive weight based on the notion of game hypothesis. Then, the weighted technique for order of preference by similarity to the ideal solution (TOPSIS) process was utilized to comprehensively assess the yield, quality, and water-nitrogen use efficiency of the apples, and a binary quadratic regression model was created between the comprehensive evaluation index and water-nitrogen inputs. The results showed that the effects of irrigation and nitrogen levels on the fruit yield, irrigation water use efficiency (IWUE), total water use efficiency (TWUE), nitrogen partial factor productivity (NPFP), and quality of mountain apples were significant (P < 0.05). The apple yield and TWUE first improved and then diminished with an escalating quantity of water-nitrogen inputs, the IWUE diminished with a boost in the irrigation quantity, the NPFP dwindled when the nitrogen amount was increased. The best water and nitrogen inputs for apple yield, quality, or water-nitrogen use efficiency were dissimilar. The best comprehensive evaluation index was DILNM treatment, and the worst comprehensive evaluation index was DISNL treatment, based on the TOPSIS system. The interval of irrigation and nitrogen attained from the mathematic model ranged in 95-115 mm and 470-575 kg ha-1, respectively. The outcome of this study may perhaps offer a theoretical basis for the scientific research of surge-root irrigation and the managing of mountain apple tree irrigation and fertilization in the Loess Plateau, China.

5.
J Cancer ; 7(2): 184-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819642

RESUMO

The renin-angiotensin system (RAS) plays important roles in tumorigenesis and is involved with several hallmarks of cancer. Evidence shows that angiotensin II (AngII) type 1 receptor (AT1R) blockers may be associated with improved outcome in prostate cancer patients. Furthermore, our previous studies indicate that increased expression of Ang II type 2 receptor (AT2R) alone induced apoptosis in human prostate cancer lines, an effect that did not require Ang II. This study aimed to investigate the effects of AT2R on tumor growth in vivo and we hypothesized that AT2R over-expression would inhibit proliferation and induce apoptosis in vivo. Human prostate cancer DU145 xenograft mouse model was used to assess the effect of AT2R on tumor growth in vivo. Mice bearing a palpable tumor were chosen and divided randomly into three treatment groups: AT2R, GFP, and PBS. Then we directly injected into the xenograft tumors of the mice every three days with recombinant adenoviruses encoding AT2R (Ad5-CMV-AT2R-EGFP), EGFP (Ad5-CMV-EGFP) and PBS, respectively. The tumor sizes of the tumor bearing mice were then measured. Immunohistochemical Ki-67 staining and TUNEL assay were performed to examine the inhibitory effect of AT2R on tumor cell proliferation. The results showed that AT2R overexpression can inhibit tumor growth of prostate cancer in vivo by inhibiting proliferation and inducing apoptosis of tumor cells. GADD45A is involved in the AT2R-induced antitumor activity. This suggests that AT2R is a potentially useful gene for prostate gene therapy.

6.
PLoS One ; 9(3): e92253, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24658029

RESUMO

Increased expression of angiotensin II type 2 receptor (AT2R) induces apoptosis in numerous tumor cell lines, with either Angiotensin II-dependent or Angiotensin II-independent regulation, but its molecular mechanism remains poorly understood. Here, we used PCR Array analysis to determine the gene and microRNA expression profiles in human prostate cancer cell lines transduced with AT2R recombinant adenovirus. Our results demonstrated that AT2R over expression leads to up-regulation of 6 apoptosis-related genes (TRAIL-R2, BAG3, BNIPI, HRK, Gadd45a, TP53BP2), 2 cytokine genes (IL6 and IL8) and 1 microRNA, and down-regulation of 1 apoptosis-related gene TNFSF10 and 2 cytokine genes (BMP6, BMP7) in transduced DU145 cells. HRK was identified as an up-regulated gene in AT2R-transduced PC-3 cells by real-time RT-PCR. Next, we utilized siRNAs to silence the up-regulated genes to further determine their roles on AT2R overexpression mediated apoptosis. The results showed downregulation of Gadd45a reduced the apoptotic effect by ∼30% in DU145 cells, downregulation of HRK reduced AT2R-mediated apoptosis by more than 50% in PC-3 cells, while downregulation of TRAIL-R2 enhanced AT2R-mediated apoptosis more than 4 times in DU145 cells. We also found that the effects on AT2R-mediated apoptosis caused by downregulation of Gadd45a, TRAIL-R2 and HRK were independent in activation of p38 MAPK, p44/42 MAPK and p53. Taken together, our results demonstrated that TRAIL-R2, Gadd45a and HRK may be novel target genes for further study of the mechanism of AT2R-mediated apoptosis in prostate cancer cells.


Assuntos
Apoptose/genética , Neoplasias da Próstata/patologia , Receptor Tipo 2 de Angiotensina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/biossíntese , Análise em Microsséries , Neoplasias da Próstata/genética , Transdução Genética , Regulação para Cima
7.
PLoS One ; 8(12): e83754, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24391821

RESUMO

Increasing evidence suggests that the renin-angiotensin system (RAS) plays an important role in tumorigenesis. The interaction between Angiotensin II (AngII) and angiotensin type 1 receptor (AT1R) may have a pivotal role in hepatocellular carcinoma (HCC) and therefore, AT1R blocker and angiotensin I-converting enzyme (ACE) inhibitors may have therapeutic potential in the treatment of hepatic cancer. Although the involvement of AT1R has been well explored, the role of the angiotensin II Type 2 receptor (AT2R) in HCC progression remains poorly understood. Thus, the aim of this study was to explore the effects of AT2R overexpression on HCC cells in vitro and in mouse models of human HCC. An AT2R recombinant adenoviral vector (Ad-G-AT2R-EGFP) was transduced into HCC cell lines and orthotopic tumor grafts. The results indicate that the high dose of Ad-G-AT2R-EGFP-induced overexpression of AT2R in transduced HCC cell lines produced apoptosis. AT2R overexpression in SMMC7721 cells inhibited cell proliferation with a significant reduction of S-phase cells and an enrichment of G1-phase cells through changing expression of CDK4 and cyclinD1. The data also indicate that overexpression of AT2R led to apoptosis via cell death signaling pathway that is dependent on activation of p38 MAPK, pJNK, caspase-8 and caspase-3 and inactivation of pp42/44 MAPK (Erk1/2). Finally, we demonstrated that moderately increasing AT2R expression could increase the growth of HCC tumors and the proliferation of HCC cells in vivo. Our findings suggest that AT2R overexpression regulates proliferation of hepatocellular carcinoma cells in vitro and in vivo, and the precise mechanisms of this phenomenon are yet to be fully determined.


Assuntos
Apoptose , Carcinoma Hepatocelular/patologia , Ciclo Celular , Proliferação de Células , Neoplasias Hepáticas/patologia , Receptor Tipo 2 de Angiotensina/metabolismo , Adenoviridae/genética , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptor Tipo 2 de Angiotensina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 32(6): 857-61, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22699070

RESUMO

OBJECTIVE: To compare the efficiency of three different serotypes of adeno-associated virus (AAV) in mediating the transfection of enhanced green fluorescent protein (EGFP) in Tibet minipig fetal fibroblasts (PFFs). METHODS: Three recombinant AAV of different serotypes encoding EGFP were constructed and transfected into primary cultured PFFs at the multiplicity of infection (MOI) ranging from 10(3) to 10(5). The expression rates of EGFP in the PFFs were assessed 72 h after the infection by flow cytometry, and the transfected PFFs were observed under inverted fluorescence microscope. The toxicity of AAVs to PFFs was analyzed using MTT assay. RESULTS: The transfection efficiency of AAV2-EGFP increased with MOI. At the MOI of 10(3), the transfection efficiency of AAV2-EGFP was (33.68∓1.18)%, which increased to (50.80∓2.59)% at the MOI of 10(4) but without obvious further increase at the MOI of 10(5). The other two serotypes of the virus (AAV8 and AAV9) showed no obvious changes in the infection efficiency at any MOIs. The transfection efficiency of AAV8 was (8.3∓0.02)% and that of AAV9 was (2.20∓1.02)% at the MOI of 10(5). Transfection with the 3 viruses caused no adverse effects on the normal cell growth of the PFFs. CONCLUSIONS: AAV2 has a significantly higher infection rate in cultured PFFs than AAV8 and AAV9, and the latter two have a rather low infection efficiency. All the three AAVs have no cell toxicity to the PFFs.


Assuntos
Dependovirus/genética , Fibroblastos , Proteínas de Fluorescência Verde/genética , Transfecção , Animais , Animais Geneticamente Modificados , Linhagem Celular , Dependovirus/classificação , Vetores Genéticos , Suínos , Porco Miniatura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA