• Journal of Microbiology and Biotechnology
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• 제26권6호
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• pp.1018-1025
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• 2016

Probiotics are considered as the best effective alternatives to antibiotics. The aim of this study was to characterize the probiotic potential of lactobacilli for use in swine farming by using in vitro evaluation methods. A total of 106 lactic acid bacterial isolates, originating from porcine feces, were first screened for the capacity to survive stresses considered important for putative probiotic strains. Sixteen isolates showed notable acid and bile resistance, antibacterial activity, and adherence to intestinal porcine epithelial cells (IPEC-1). One isolate, LR1, identified as Lactobacillus reuteri, was selected for extensive study of its probiotic and functional properties in IPEC-1 cell models. L. reuteri LR1 exhibited good adhesion to IPEC-1 cells and could inhibit the adhesion of enterotoxigenic Escherichia coli (ETEC) to IPEC-1 cells. L. reuteri LR1 could also modulate transcript and protein expression of cytokines involved in inflammation in IPEC-1 cells; the Lactobacillus strain inhibited the ETEC-induced expression of proinflammatory transcripts (IL-6 and TNF-α) and protein (IL-6), and increased the level of anti-inflammatory cytokine (IL-10). Measurement of the permeation of FD-4 showed that L. reuteri LR1 could maintain barrier integrity in monolayer IPEC-1 cells exposed to ETEC. Immunolocalization experiments showed L. reuteri LR1 could also prevent ETEC-induced tight junction ZO-1 disruption. Together, these results indicate that L. reuteri LR1 exhibits desirable probiotic properties and could be a potential probiotic for use in swine production.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5433-5436
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• 2014

Conventional chemotherapy against hepatocellular carcinoma typically causes various side effects. Our previous study showed that cecropin of Musca domestica can induce apoptosis in human hepatocellular carcinoma BEL-7402 cells in vitro. However, whether cecropin inhibits BEL-7402 cell in vivo and the question of possible side effects remained undentified. The present study confirmed tumor-inhibitory effects of cecropin in vivo, and furthermore strongly suggested that cecropin cytotoxicity in BEL-7402 cells in vivo may be mainly derived from its pro-apoptotic action. Specifically, we found that cecropin exerted no obvious side effects in tumor-bearing mice as it had no significant hematoxicity as well as visceral toxicity. Therefore, cecropin may be a potential candidate for further investigation as an antitumor agent against hepatocellular carcinoma.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.34-45
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• 2021

On February 18, 2019, the Chinese government officially released the Outline of the Development Plan for the Guangdong-Hong Kong-Macao Greater Bay Area, which will lead the country in a new round of reform and opening-up. The Greater Bay Area will become a dynamic world-class city cluster, an international scientific and technological innovation center with global influence, an important support for the development of the "One Belt And One Road", a demonstration area for in-depth cooperation between the mainland and Hong Kong and Macao, and a high-quality living area for living, working and traveling. Non-Pearl River Delta(Non-PRD) cities in Guangdong Province are adjacent to the Guangdong-Hong Kong-Macao Greater Bay Area, so it is of practical significance to promote the high-quality development of urban tourism from an international perspective. Based on the panel data released in Guangdong Yearbook 2019, this paper uses the envelopment data analysis (DEA) method to explore ways to promote the high-quality tourism development of Non-PRD cities in Guangdong Province based on the perspective of international development.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.611-616
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• 1993

On the basis of the data collected from various fields , the energy input output state in the crop-growing sub-system in Guangdong is estimated and analyzed. Results show that the input of the artificial supplementary energy is approximately 201x105 Kcal/ha. year and the input and output ratio equals 1 : 4.73. Measures for improving productivity and speeding up the development of agricultural mechanization in Guangdong are eventually suggested.

• Parasites, Hosts and Diseases
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• 제57권1호
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• pp.9-15
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• 2019

Melting temperature shift ($T_m-shift$) is a new detection method that analyze the melting curve on real-time PCR thermocycler using SYBR Green I fluorescent dye. To establish a $T_m-shift$ method for the detection of Ancylostoma ceylanicum and A. tubaeforme in cats, specific primers, with GC tail of unequal length attached to their 5' end, were designed based on 2 SNP loci (ITS101 and ITS296) of the internal transcribed spacer 1 (ITS1) sequences. The standard curve of $T_m-shift$ was established using the standard plasmids of A. ceylanicum (AceP) and A. tubaeforme (AtuP). The $T_m-shift$ method stability, sensitivity, and accuracy were tested with reference to the standard curve, and clinical fecal samples were also examined. The results demonstrated that the 2 sets of primers based on the 2 SNPs could accurately distinguish between A. ceylanicum and A. tubaeforme. The coefficient of variation (CV) of $T_m$- values of AceP and AtuP was 0.07% and 0.06% in ITS101 and was 0.06% and 0.08% in ITS296, respectively. The minimum detectable DNA concentration was $5.22{\times}10^{-6}$ and $5.28{\times}10^{-6}ng/{\mu}l$ samples of AceP and AtuP, respectively. The accuracy of $T_m-shift$ method reached 100% based on examination of 10 hookworm DNA samples with known species. In the clinical detection of hookworm in 69 stray cat fecal sample, the $T_m-shift$ detection results were consistent with the microscopic examination and successfully differentiated between the 2-hookworm species. In conclusion, the developed method is a rapid, sensitive and accurate technique and can provide a promising tool for clinical detection and epidemiological investigation of cat-derived hookworms.

• The Korean Journal of Physiology and Pharmacology
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• 제18권5호
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• pp.377-381
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• 2014

Propofol is a widely used anesthetic. Many studies have shown that propofol has direct effects on blood vessels, but the precise mechanism is not fully understood. Secondary intrapulmonary artery rings from male rats were prepared and mounted in a Multi Myograph System. The following constrictors were used to induce contractions in isolated artery rings: high $K^+$ solution (60 mmol/L); U46619 solution (100 nmol/L); 5-hydroxytryptamine (5-HT; $3{\mu}mol/L$); or phenylephrine (Phe; $1{\mu}mol/L$). The relaxation effects of propofol were tested on high $K^+$ or U46619 precontracted rings. Propofol also was added to induce relaxation of rings preconstricted by U46619 after pretreatment with the nitric oxide synthase inhibitor $N^G$-nitro-L-arginine methyl ester (L-NAME). The effects of propofol on $Ca^{2+}$ influx via the L-type $Ca^{2+}$ channels were evaluated by examining contraction-dependent responses to $CaCl_2$ in the absence or presence of propofol (10 to $300{\mu}mol/L$). High $K^+$ solution and U46619 induced remarkable contractions of the rings, whereas contractions induced by 5-HT and Phe were weak. Propofol induced dose-dependent relaxation of artery rings precontracted by the high $K^+$ solution. Propofol also induced relaxation of rings precontracted by U46619 in an endothelium-independent way. Propofol at different concentrations significantly inhibited the $Ca^{2+}$-induced contractions of pulmonary rings exposed to high $K^+$-containing and $Ca^{2+}$-free solution in a dose-dependent manner. Propofol relaxed vessels precontracted by the high $K^+$ solution and U46619 in an endothelium-independent way. The mechanism for this effect may involve inhibition of calcium influx through voltage-operated calcium channels (VOCCs) and receptor-operated calcium channels (ROCCs).

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1252-1257
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• 2007

This study was conducted to determine the effect of dietary soy isoflavone (ISF, 0 and 20 mg/kg) on performance, meat quality and antioxidative property in male broilers. Six replicates of 45 birds (42 d old) were used for each treatment. The birds were fed soybean meal-free diets containing 3% oxidized fish oil (acid value, 6.76 mg potassium hydroxide/g; and peroxide value, 6.18 meq/kg) for 3 wk. The results showed that average daily gain, feed intake, feed conversion and carcass traits were not affected by soy ISF. Compared with the control group, breast muscle color redness value and water holding capacity were increased (p<0.05) by ISF supplementation. The activity of plasma catalase was increased by supplementing with 20 mg ISF/kg diet. In breast muscle, Broilers fed 20 mg ISF/kg had decreased production of malondialdehyde and lactic acid. The ISF supplementation elevated total antioxidative capacity and activities of total superoxide dismutase and glutathione peroxidase. The results indicated that dietary ISF could increase redness and water holding capacity of meat, and antioxidative property of meat in male broilers fed oxidized fish oil diet.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.569-578
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• 2015

Cold water paddy field soils are relatively unproductive, but can be ameliorated by supplementing with inorganic fertilizer from animal waste-based composts. The yield of two rice cultivars was significantly raised by providing either chicken manure or cow dung-based compost. The application of these composts raised the soil pH as well as both the total nitrogen and ammonium nitrogen content, which improved the soil's fertility and raised its nitrification potential. The composts had a measurable effect on the abundance of nitrogencycling-related soil microbes, as measured by estimating the copy number of various bacterial and archaeal genes using quantitative real-time PCR. The abundance of ammonia oxidizing archaea and bacteria was markedly encouraged by the application of chicken manure-based compost. Supplementation with the composts helped promote the availability of soil nitrogen in the cold water paddy field, thereby improving the soil's productivity and increasing the yield of the rice crop.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.428-437
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• 2007

The potential for humic substances to serve as terminal electron acceptors in microbial respiration and the effects of humic substances on microbial azoreduction were investigated. The dissimilatory azoreducing microorganism Shewanella decolorationis S12 was able to conserve energy to support growth from electron transport to humics coupled to the oxidation of various organic substances or $H_2$. Batch experiments suggested that when the concentration of anthraquinone-2-sulfonate (AQS), a humics analog, was lower than 3 mmol/l, azoreduction of strain S12 was accelerated under anaerobic condition. However, there was obvious inhibition to azoreduction when the concentration of the AQS was higher than 5 mmol/l. Another humics analog, anthraquinone-2-sulfonate (AQDS), could still prominently accelerate azoreduction, even when the concentration was up to 12 mmol/l, but the rate of acceleration gradually decreased with the increasing concentration of the AQDS. Toxic experiments revealed that AQS can inhibit growth of strain S12 if the concentration past a critical one, but AQDS had no effect on the metabolism and growth of strain S12 although the concentration was up to 20 mmol/l. These results demonstrated that a low concentration of humic substances not only could serve as the terminal electron acceptors for conserving energy for growth, but also act as redox mediator shuttling electrons for the anaerobic azoreduction by S. decolorationis S12. However, a high concentration of humic substances could inhibit the bacterial azoreduction, resulting on the one hand from the toxic effect on cell metabolism and growth, and on the other hand from competion with azo dyes for electrons as electron acceptor.

• Journal of Animal Science and Technology
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• 제57권3호
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• pp.7.1-7.7
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• 2015

To meet the increasing demands of specific pathogen free (SPF) minipigs in biomedical researches, 8 pregnant Chinese Wuzhishan minipigs (WZSP) sows with clear background were chosen to obtain SPF WZSP by hysterectomy. At $111{\pm}days2$ of the pregnancy, piglets were aseptically taken out from the sows and artificially suckled for 40 to 45 days in the positive isolators. Then, the piglets defined as F0 were transferred to barrier environment and fed with standard feeds. The original SPF colony was formed for breeding by selected piglets from F0 group of 6-8 months old. Biological characteristics of SPF WZSP were collected and further compared to those of conventional (CV) WZSP, including growth performance, reproductive performance, hematology and blood biochemistry, and major pathogens detection. As a result, 61 F0 piglets were obtained from 8 candidate sows, and 55 out of them survived. After strictly selection, 35 F0 piglets were used to form the original SPF colony, which produced 14 litters of SPF piglets defined as F1. Piglet survival rates, growth performance, and reproductive performance of SPF WZSP were similar to CV WZSP. Some hematology and blood biochemistry parameters showed significant differences between SPF and CV WZSP. Eighteen kinds of pathogens were identified to be free in F0 and F1 SPF colony by repeated pathogen detections. In conclusion, we established a satisfied SPF WZSP colony maintaining original characteristics, free of controlled diseases, and being proved to be a suitable laboratory animal.