43 research outputs found
Bioleaching of Sphalerite by the Native Mesophilic Iron-oxidizing Bacteria from a Lead-Zinc Tailing
AbstractAn isolated native mesophilic iron-oxidizing bacteria, acidithiobacillus ferrooxidans, was used to extract zinc by the bioleaching method from a typical lead-zinc tailing. Experiments were carried out by mixed culture of the mesophilic strain in the shake flasks and the different influencing factors such as pH, temperature, inoculation cell number, as well as slurry concentration on the process of bioleaching were investigated. The results indicated that the extraction efficiency of zinc was relevant with these variables and more than 70% of sphalerite was dissolved on the condition of with pH 2.0, initial ferrous concentration of 10g/L and slurry concentration of 10wt.% during 25 d, while without bacteria, 22% of Zn was merely extracted
Hairy root transgene expression analysis of a secretory peroxidase (PvPOX1) from common bean infected by Fusarium wilt
Plant peroxidases (POXs) are one of the most important redox enzymes in the defense responses. However, the large number of different plant POX genes makes it necessary to carefully confirm the function of each paralogous POX gene in specific tissues and disease interactions. Fusarium wilt is a devastating disease of common bean caused by Fusarium oxysporum f. sp. phaseoli. In this study, we evaluated a peroxidase gene, PvPOX1, from a resistant common bean genotype, CAAS260205 and provided direct evidence for PvPOX1âs role in resistance by transforming the resistant allele into a susceptible common bean genotype, BRB130, via hairy root transformation using Agrobacterium rhizogenes. Analysis of PvPOX1 gene over-expressing hairy roots showed it increased resistance to Fusarium wilt both in the roots and the rest of transgenic plants. Meanwhile, the PvPOX1 expressive level, the peroxidase activity and hydrogen peroxide (H2O2) accumulation were also enhanced in the interaction. The result showed that the PvPOX1 gene played an essential role in Fusarium wilt resistance through the occurrence of reactive oxygen species (ROS) induced hypersensitive response. Therefore, PvPOX1 expression was proven to be a valuable gene for further analysis which can strengthen host defense response against Fusarium wilt through a ROS activated resistance mechanism
Potential of genotype VII Newcastle disease viruses to cause differential infections in chickens and ducks
Newcastle disease (ND), caused by ND virus (NDV), is one of the most infectious and economically important diseases of the poultry industry worldwide. While infections are reported in a wide range of avian species, the pathogenicity of chicken-origin virulent NDV isolates in ducks remains elusive. In this study, two NDV strains were isolated and biologically and genetically characterized from an outbreak in chickens and apparently healthy ducks. Pathogenicity assessment indices, including the mean death time (MDT), intracerebral pathogenicity index (ICPI) and cleavage motifs in the fusion (F) protein, indicated that both isolates were velogenic in nature. While these isolates carried pathogenic characteristics, interestingly they showed differential pathogenicity in ducks. The chicken-origin isolate caused high (70%) mortality, whereas the duck-origin virus resulted in low (20%) mortality in 4-week-old ducks. Intriguingly, both isolates showed comparable disease pathologies in chickens. Full-genome sequence analysis showed that the virus genome contains 15 192 nucleotides and carried features that are characteristic of velogenic strains of NDV. A phylogenetic analysis revealed that both isolates clustered in class II and genotype VII. However, there were several mutations in the functionally important regions of the fusion (F) and haemagglutinin-neuraminidase (HN) proteins, which may be responsible for the differential pathogenicity of these viruses in ducks. In summary, these results suggest that NDV strains with the same genotype show differential pathogenicity in chickens and ducks. Furthermore, chicken-origin virulent NDVs are more pathogenic for ducks than duck-origin viruses. These findings propose a role for chickens in the evolution of viral pathogenicity and the potential genetic resistance of ducks to poultry viruses
Supplementation of Vitamin E Protects Chickens from Newcastle Disease Virus-Mediated Exacerbation of Intestinal Oxidative Stress and Tissue Damage
BACKGROUND/AIMS: Newcastle disease virus (NDV) causes a highly devastating and contagious disease in poultry, which is mainly attributed to extensive tissue damages in the digestive, respiratory and nervous systems. However, nature and dynamics of NDV-induced oxidative stresses in the intestine of chickens remain elusive. METHODS: In this study, we examined the magnitude of intestinal oxidative stress and histopathological changes caused by the virulent NDV infection, and explored the protective roles of vitamin E (vit. E) in ameliorating these pathological changes. For these purposes, chickens were divided into four groups namely i) non supplemented and non-challenged (negative control, CON); ii) no supplementation of vit. E but challenged with ZJ1 (positive control, NS+CHA); iii) vit. E supplementation at the dose of 50 IU/day/Kg body weight and ZJ1 challenge (VE50+CHA); and 4) vit. E supplementation at the dose of 100 IU/day/Kg body weight and ZJ1 challenge (VE100+CHA). In all groups, we analyzed concentrations of glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (T-AOC), and activity of glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) using biochemical methods. The virus loads were determined by quantitative RT-PCR and antibody titers by hemagglutination inhibition assays. We also examined the histopathological changes in the duodenal and jejunal mucosa at 3 and 5-day post infection (dpi) with NDV. RESULTS: A significant elevation in the NO level was observed in NDV challenged chickens compared to the CON chickens at 2 dpi. The MDA contents were significantly increased whereas GSH was significantly decreased in NDV-challenged chickens compared to control. Furthermore, activities of GST, CAT, SOD, as well as the TOAC were markedly decreased in challenged chickens in comparison with control. Virus copy numbers were higher in NDV infected NS+CHA group compared to other groups. Severe histopathological changes including inflammation, degeneration and broken villi were observed in the intestine of NDV challenged chickens. However, all these malfunctions of antioxidant system and pathological changes in the intestine were partially or completely reversed by the vit. E supplementation. CONCLUSIONS: Our results suggest that NDV infection causes oxidative stress and histopathological changes in the duodenum and jejunum of chickens, which can be partially or fully ameliorated by supplementation of vit. E. Additionally, these findings suggest that oxidative stress contributes to the intestinal damages in NDV infected chickens. These findings will help to understand the pathogenesis of NDV and further investigation of therapeutic agents for control of Newcastle disease
Production, characterization, and epitope mapping of a monoclonal antibody against genotype VII Newcastle disease virus V protein
Newcastle disease virus (NDV) V protein is crucial for viral interferon (IFN) antagonism and virulence, determining its host range restriction. However, little information is available on the B cell epitopes of V protein and the subcellular movement of V protein in the process of NDV infection. In this study, the monoclonal antibody (mAb) clone 3D7 against genotype VII NDV V protein was generated by immunizing mice with a purified recombinant His-tagged carboxyl-terminal domain (CTD) region of V protein. Fine epitope mapping analysis and B-cell epitope prediction indicated that mAb 3D7 recognized a linear epitope 152RGPAELWK159, which is located in the V protein CTD region. Sequence alignment showed that the mAb clone 3D7-recognized epitope is highly conserved among Class II genotype VII NDV strains, but not among other genotypes, suggesting it could serve as a genetic marker to differentiate NDV genotypes. Furthermore, the movement of V protein during NDV replication in infected cells were determined by using this mAb. It was found that V protein localized around the nucleus during virus replication. The establishment of V protein-specific mAb and identification of its epitope extend our understanding of the antigenic characteristics of V protein and provide a basis for the development of epitope-based diagnostic assays
Prosedur penyelesaian pembiayaan bermasalah pada akad mudharabah dalam rangka meminimalisir resiko di BMT Amanah Usaha Mulia Magelang
Permasalah kehidupan perekonomian yang sulit, membuat masyarakat berinisiatif untuk membuka usaha sendiri. Mereka membutuhkan suatu bantuan berupa dana untuk memperlancar usahanya, maka BMT Amanah Usaha Mulia Magelang ikut untuk mengembangkan produknya yaitu pembiayaan mudharabah sesuai perkembangan dunia perbankan dalam target peningkatan keuntungan dan menyejahterakan masyarakat. Dengan diberikanya pembiayaan tersebut, terkadang muncul adanya pembiayaan bermasalah dikarenakan ada beberapa faktor diantaranya ketidakmampuan anggota untuk membayar tepat waktu atau jatuh tempo pembayaran diakibatkan karena usaha anggota yang kurang lancar dan lain sebagaianya.
Tugas Akhir ini berjudul â Prosedur Penyelesaian Pembiayaan Bermasalah pada Akad Mudharabah Dalam Rangka Meminimalisir Risikoâ Berdasarkan judul tersebut dapat diambil rumusan masalah yaitu apa penyebab terjadinya pembiayaan bermasalah pada BMT Amanah Usaha Mulia Magelang dan bagaimana prosedur penyelesaian pembiayaaan bermasalah pada akad mudharabah di BMT Amanah Usaha Mulia Magelang.
Penelitian ini merupakan penelitian lapangan dimana sumber data yang digunakan berasal dari data primer dan sekunder yang diperoleh melalui metode wawancara dengan manajer, bagian pembiayaan dan dokumentasi. Metode yang digunakan dalam penelitian ini adalah deskriptif kualitatif yang bertujuan untuk menggambarkan secara sistematis dan akurat mengenai objek penelitian.
Berdasarkan hasil penelitian dapat disimpulkan bahwa penyebab terjadinya pembiayaan bermasalah yaitu faktor internal meliputi kurang telitinya petugas BMT dalam menganalisi data calon anggota, kurang disiplinya dalam penagihan dan eksternal meliputi karakter anggota yang kurang baik, usahanya bangkrut dan terjadinya bencana alam yang tidak terduga. Adapun prosesdur yang digunakan BMT Amanah Usaha Mulia dalam menyelesaian pembiayaan bermasalah pada akad mudharabah dengan cara kekeluargaan atau musyawarah dengan anggota, penjadwalan kembali (rescheduling), persyaratan kembali (reconditioning), pengambilan jaminan (eksekusi), dan write off final. Di BMT Amanah Usaha Mulia dalam penyelesaian pembiayaan bermasalah jarang menngunakan jalur hukum, tetapi sering menggunakan cara kekeluargaan yang dianggap lebih efektif dan eksekusi jaminan apabila anggota tersebut sudah mengalami macet atau bermasalah
An optimized shortâterm steroid therapy for chronic drugâinduced liver injury: A prospective randomized clinical trial
Background and AimsThe use of corticosteroids in chronic drug-induced liver injury (DILI) is an important issue. Our previous randomized controlled trial showed that patients with chronic DILI benefited from a 48-week steroid stepwise reduction (SSR) regimen. However, it remains unclear whether a shorter course of therapy can achieve similar efficacy. In this study, we aimed to assess whether a 36-week SSR can achieve efficacy similar to that of 48-week SSR.MethodsA randomized open-label trial was performed. Eligible patients were randomly assigned to the 36- or 48-week (1:1) SSR group. Liver biopsies were performed at baseline and at the end of treatment. The primary outcome was the proportion of patients with relapse rate (RR). The secondary outcomes were improvement in liver histology and safety.ResultsOf the 90 participants enrolled, 84 (87.5%) completed the trial, and 62 patients (68.9%) were women. Hepatocellular damage was observed in 53.4% of the cohort. The RR was 7.1% in the 36-week SSR group but 4.8% in the 48-week SSR group, as determined by per-protocol set analysis (pâ=â1.000). Significant histological improvements in histological activity (93.1% vs. 92.9%, pâ=â1.000) and fibrosis (41.4% vs. 46.4%, pâ=â.701) were observed in both the groups. Biochemical normalization time did not differ between the two groups. No severe adverse events were observed.ConclusionsBoth the 36- and 48-week SSR regimens demonstrated similar biochemical response and histological improvements with good safety, supporting 36-week SSR as a preferable therapeutic choice (ClinicalTrials.gov, NCT03266146)
Optimal Subsidy Policy for Green Energy Trading Among Three Parties: A Game Theoretical Approach
In this paper, we present the optimal strategy for green energy trading among three parties: user residents (URs), service provider (SP), and the grid. The URs make decisions about the amount of generated green energy for self-usage and trading. The SP collects green energy from URs and trade in the market and receives subsidy from the grid. The grid which is government owned subsidizes the SP to promote the adoption of green energy, so that the environment can be improved and social surplus benefits. To obtain insights of such a highly coupled system, we consider a monopoly market, where there are a group of URs trading with a single service provider. To find the optimal strategy of the three parties, we propose a three-stage Stackelberg game model. Besides, the grid’s optimal subsidy policy, the SP’s optimal pricing strategies, and URs’ optimal usage strategy are also provided in each stage. Both the analytical and simulation results show that, the optimal decisions such as the amount of green energy generated by UR and the subsidy given by the grid are all decreasing functions of URs’ average cost. High infrastructure and operation costs to obtain green energy deteriorate each party’s payoff and the whole system’s performance