• Title/Summary/Keyword: lethal factor

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Honey Bee Venom (Apis mellifera) Contains Anticoagulation Factors and Increases the Blood-clotting Time

  • Zolfagharian, Hossein;Mohajeri, Mohammad;Babaie, Mahdi
    • Journal of Pharmacopuncture
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    • v.18 no.4
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    • pp.7-11
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    • 2015
  • Objectives: Bee venom (BV) is a complex mixture of proteins and contains proteins such as phospholipase and melittin, which have an effect on blood clotting and blood clots. The mechanism of action of honey bee venom (HBV, Apis mellifera) on human plasma proteins and its anti-thrombotic effect were studied. The purpose of this study was to investigate the anti-coagulation effect of BV and its effects on blood coagulation and purification. Methods: Crude venom obtained from Apis mellifera was selected. The anti-coagulation factor of the crude venom from this species was purified by using gel filtration chromatography (sephadex G-50), and the molecular weights of the anti-coagulants in this venom estimated by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Blood samples were obtained from 10 rabbits, and the prothrombin time (PT) and the partial thromboplastin time (PTT) tests were conducted. The approximate lethal dose (LD) values of BV were determined. Results: Crude BV increased the blood clotting time. For BV concentrations from 1 to 4 mg/mL, clotting was not observed even at more than 300 seconds, standard deviations $(SDs)={\pm}0.71$; however, clotting was observed in the control group 13.8 s, $SDs={\pm}0.52$. Thus, BV can be considered as containing anti-coagulation factors. Crude BV is composed 4 protein bands with molecular weights of 3, 15, 20 and 41 kilodalton (kDa), respectively. The $LD_{50}$ of the crude BV was found to be $177.8{\mu}g/mouse$. Conclusion: BV contains anti-coagulation factors. The fraction extracted from the Iranian bees contains proteins that are similar to anti-coagulation proteins, such as phospholipase $A_2(PLA_2)$ and melittin, and that can increase the blood clotting times in vitro.

Immuno-Modulatory Effects of Bacteriocin-Producing Pediococcus pentosaceus JWS 939 in Mice

  • Choi, Hyun-Jong;Kim, Ji-Ye;Shin, Myeong-Su;Lee, Sang-Myeong;Lee, Wan-Kyu
    • Food Science of Animal Resources
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    • v.31 no.5
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    • pp.719-726
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    • 2011
  • Pediococcus pentosaceus JWS 939 (JWS 939) is a nonpathogenic bacteriocin-producing probiotic isolated from the duck intestine. This study assessed the immunomodulatory effects of JWS 939 and compared them with those of Lactobacillus rhamnosus GG (LGG), a well-known immune enhancer. The immune-enhancing effects of JWS 939 were measured by measuring the production of nitric oxide (NO) and cytokines in C57BL/6 mouse peritoneal macrophages. In addition, to assess the immune enhancement abilities of JWS 939, in vivo, a Listeria monocytogenes challenge mice model was used. The results showed that heat-killed JWS 939 induced more NO and interleukin (IL)-$1{\beta}$ production in mouse peritoneal macrophages than in LGG, and that oral administration of viable JWS 939 in mice increased more NO, IL-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$ level than in LGG in serum upon L. monocytogenes challenge. In addition, mice fed with JWS 939 had a longer survival time after lethal challenge with L. monocytogenes, and these effects were stronger than those induced by LGG. Collectively, P. pentosaceus JWS 939 is a remarkable strain that, by releasing bacteriocin and enhancing host immune responses, may have potential as a duck feed additive to suppress pathogens.

Targeting EGFL7 Expression through RNA Interference Suppresses Renal Cell Carcinoma Growth by Inhibiting Angiogenesis

  • Xu, Han-Feng;Chen, Lei;Liu, Xian-Dong;Zhan, Yun-Hong;Zhang, Hui-Hui;Li, Qing;Wu, Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.7
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    • pp.3045-3050
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    • 2014
  • Renal cell carcinoma (RCC) is the most lethal of all urological cancers and tumor angiogenesis is closely related with its growth, invasion, and metastasis. Recent studies have suggested that epidermal growth factor-like domain multiple 7 (EGFL7) is overexpressed by many tumors, such as colorectal cancer and hepatocellular carcinoma; it is also correlated with progression, metastasis, and a poor prognosis. However, the role of EGFL7 in RCC is not clear. In this study, we examined how EGFL7 contributes to the growth of RCC using a co-culture system in vitro and a xenograft model in vivo. Downregulated EGFL7 expression in RCC cells affected the migration and tubule formation of HMEC-1 cells, but not their growth and apoptosis in vitro. The level of focal adhesion kinase (FAK) phosphorylation in HMEC-1 cells decreased significantly when co-cultured with 786-0/iEGFL7 cells compared with 786-0 cells. After adding rhEGFL7, the level of FAK phosphorylation in HMEC-1 cells was significantly elevated compared with phosphate-buffered saline (PBS) control. However, FAK phosphorylation was abrogated by EGFR inhibition. The average size of RCC local tumors in the 786-0/iEGFL7 group was noticeably smaller than those in the 786-0 cell group and their vascular density was also significantly decreased. These data suggest that EGFL7 has an important function in the growth of RCC by facilitating angiogenesis.

The Methanol Extract of Azadirachta indica A. Juss Leaf Protects Mice Against Lethal Endotoxemia and Sepsis

  • Kim, Woong-Hyun;Song, Hyun-Ok;Jin, Chun-Mei;Hur, Jong-Moon;Lee, Hwa-Sung;Jin, Han-Yong;Kim, Sung-Yeon;Park, Hyun
    • Biomolecules & Therapeutics
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    • v.20 no.1
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    • pp.96-103
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    • 2012
  • In the present study, the inhibitory effect of neem leaf extract (NLE) on lipopolysaccaride (LPS)-induced nitric oxide (NO) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) production was examined both in vitro and in vivo. In vitro study revealed that NLE treatment ($100{\mu}g/ml$) inhibits LPS (100 ng/ml)-induced NO production by 96% and TNF-${\alpha}$ production by 32%. The reduction in NO production is probably conferred by the complete suppression of inducible nitric oxide synthase (iNOS) expression. Interestingly, in vivo NLE significantly improved the survival rate of mice in an experimental sepsis model. Administration of NLE (100 mg/kg) 24 h before LPS treatment (20 mg/kg) improved the survival rate of mice by 60%. The inhibition of plasma NO and TNF-${\alpha}$ production by NLE is likely to account for the improved survival of mice. Our results suggest that NLE may present a promising avenue in the development of therapeutic agents for the treatment of inflammatory diseases.

Cadmium Accumulation in Tissue of Olive Flounder, Paralichthys olivaceus During tong Term Exposure (카드뮴 장기노출에 따른 넙치, Paralichthys olivaceus의 기관별 축적)

  • Jang Suck Woo;Kim Seong Gil;Kang Ju Chan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.5
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    • pp.480-484
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    • 2002
  • Accumulation of cadmium (Cd) was investigated in organs (gill, liver, kidney, intestine) of olive flounder (Paralichthys olivaceus) exposed to sub-lethal concentration (5, 10, 50, 100 $\mu$g/L) of Cd for 30 days. Cd exposure resulted in an increased Cd accumulation in liver of flounder for exposure periods and Cd concentration, and Cd accumulation increased linearly with the exposure time. At 20 days of Cd exposure. the order of Cd accumulation in organs was Bill>intestine>liver>kidney and after 30 days of exposure, Cd accumulation in organs was intestine>liver>gill>idney. An inverse relationship was observed between the accumulation factor (AS) and the exposure level, but AE shows an increase with exposure time.

Establishment of Bioassay System for Developing New Insecticides I. Effects of Organic Solvents on the Toxicity against Insects, Phytotoxicity and Solubility of Compounds (살충제 개발을 위한 생물검정법의 확립 I. 각종 유기 용매가 곤충의 독성과 약해 및 화합물의 용해성에 미치는 영향)

  • 안용준;조광연
    • Korean journal of applied entomology
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    • v.31 no.2
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    • pp.182-189
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    • 1992
  • The influnces of 9 kinds of solvents on the toxicities against several insect species, phytotoxicity and solubility of compounds were evaluated by means of leaf dipping and spray methods. In case of the spray application, density and vapor pressure seemed to be a contributing factor to lethal toxicity against brown planthopper and diamond-back moth, respectively; the bigger the property of density and the smaller the vapor pressure gave the stronger toxicity. It appeared that the toxicity of solvents was not correlated with anyone of physical properties such as boiling point, dipole moment, dielectric constant, surface tension and viscosity. Spray treatment gave more toxicity to insects than leaf dipping treatment. Although dielectric constant and dipole moment seemed to be contributing factors to phytotoxic damage to rice seedling and bean plants, respectively, no general correlation between phytoxicity and the other physical properties was found. Leaf dipping application caused stronger phytotoxicity than spray application. It is concluded that 5% acetone solution may be most suitable to test chemicals because of its favorable solubility of compounds, lower toxicity to insects, and lower phytotoxicity.

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Differential Induction of Septic Shock by Lipopolysacchrides from E. coli and S. abortus (S. abortus 유래 LPS와 E. coli 유래 LPS에 의한 패혈증성 쇽 유도 작용 비교)

  • Cho, Jae-Youl;Yoo, Eun-Sook
    • YAKHAK HOEJI
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    • v.51 no.1
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    • pp.44-50
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    • 2007
  • Acute septic shock is one of inflammatory diseases mediated by pro-inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$. In this study, we examined the pathological difference and mechanism of lipopolysaccharides isolated from E. coli (E-LPS) or S. abortus (S-LPS) on inducing acute septic shock in ICR mouse. All mice were died by intraperitoneal treatment of S-LPS with 0.75 mg/kg, whereas E-LPS treated with even 3 mg/kg only showed 30% of mice lethal, indicating that S-LPS may be more feasible in triggering a strong septic shock condition. The secretion pattern of TNF-${\alpha}$, a critical pro-inflammatory cytokine in septic shock condition, was also distinct between E-LPS- and S-LPS-treated groups. Thus, S-LPS strikingly increased serum level of TNF-${\alpha}$ (6 ng/ml) at 1 h, while E-LPS just displayed at 2 ng/ml level. However the interaction of S-LPS with LPS receptor toll like receptor (TLR)-4, was not stronger than that of E-LPS, according to experiments with macrophage cell line RAW264.7 cells. Thus, E-LPS rather than S-LPS strongly enhanced the production of TNF-${\alpha}$. Interestingly, S-LPS more strongly up-regulated splenocyte proliferation, compared to E-LPS group, whereas there was no difference between S- or E-LPS treated groups in proliferation of Balb/c- or C57BL/6-originated splenic lymphocytes. Therefore, our data suggest that S-LPS is a more active endotoxin and that the strong septic shock-inducing effect of S-LPS seems due to the enhancement of early TNF-${\alpha}$ production and S-LPS-sensitive lymphocyte proliferation.

A Detecting Technique for the Climatic Factors that Aided the Spread of COVID-19 using Deep and Machine Learning Algorithms

  • Al-Sharari, Waad;Mahmood, Mahmood A.;Abd El-Aziz, A.A.;Azim, Nesrine A.
    • International Journal of Computer Science & Network Security
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    • v.22 no.6
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    • pp.131-138
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    • 2022
  • Novel Coronavirus (COVID-19) is viewed as one of the main general wellbeing theaters on the worldwide level all over the planet. Because of the abrupt idea of the flare-up and the irresistible force of the infection, it causes individuals tension, melancholy, and other pressure responses. The avoidance and control of the novel Covid pneumonia have moved into an imperative stage. It is fundamental to early foresee and figure of infection episode during this troublesome opportunity to control of its grimness and mortality. The entire world is investing unimaginable amounts of energy to fight against the spread of this lethal infection. In this paper, we utilized machine learning and deep learning techniques for analyzing what is going on utilizing countries shared information and for detecting the climate factors that effect on spreading Covid-19, such as humidity, sunny hours, temperature and wind speed for understanding its regular dramatic way of behaving alongside the forecast of future reachability of the COVID-2019 around the world. We utilized data collected and produced by Kaggle and the Johns Hopkins Center for Systems Science. The dataset has 25 attributes and 9566 objects. Our Experiment consists of two phases. In phase one, we preprocessed dataset for DL model and features were decreased to four features humidity, sunny hours, temperature and wind speed by utilized the Pearson Correlation Coefficient technique (correlation attributes feature selection). In phase two, we utilized the traditional famous six machine learning techniques for numerical datasets, and Dense Net deep learning model to predict and detect the climatic factor that aide to disease outbreak. We validated the model by using confusion matrix (CM) and measured the performance by four different metrics: accuracy, f-measure, recall, and precision.

Construction and immunization with double mutant ΔapxIBD Δpnp forms of Actinobacillus pleuropneumoniae serotypes 1 and 5

  • Dao, Hoai Thu;Truong, Quang Lam;Do, Van Tan;Hahn, Tae-Wook
    • Journal of Veterinary Science
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    • v.21 no.2
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    • pp.20.1-20.13
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    • 2020
  • Actinobacillus pleuropneumoniae (APP) causes a form of porcine pleuropneumonia that leads to significant economic losses in the swine industry worldwide. The apxIBD gene is responsible for the secretion of the ApxI and ApxII toxins and the pnp gene is responsible for the adaptation of bacteria to cold temperature and a virulence factor. The apxIBD and pnp genes were deleted successfully from APP serotype 1 and 5 by transconjugation and sucrose counter-selection. The APP1ΔapxIBDΔpnp and APP5ΔapxIBDΔpnp mutants lost hemolytic activity and could not secrete ApxI and ApxII toxins outside the bacteria because both mutants lost the ApxI- and ApxII-secreting proteins by deletion of the apxIBD gene. Besides, the growth of these mutants was defective at low temperatures resulting from the deletion of pnp. The APP1ΔapxIBDΔpnp and APP5ΔapxIBDΔpnp mutants were significantly attenuated compared with wild-type ones. However, mice vaccinated intraperitoneally with APP5ΔapxIBDΔpnp did not provide any protection when challenged with a 10-times 50% lethal dose of virulent homologous (APP5) and heterologous (APP1) bacterial strains, while mice vaccinated with APP1ΔapxIBDΔpnp offered 75% protection against a homologous challenge. The ΔapxIBDΔpnp mutants were significantly attenuated and gave different protection rate against homologous virulent wild-type APP challenging.

Protective efficacy of a novel multivalent vaccine in the prevention of diarrhea induced by enterotoxigenic Escherichia coli in a murine model

  • Zhao, Hong;Xu, Yongping;Li, Gen;Liu, Xin;Li, Xiaoyu;Wang, Lili
    • Journal of Veterinary Science
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    • v.23 no.1
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    • pp.7.1-7.14
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    • 2022
  • Background: Enterotoxigenic Escherichia coli (ETEC) infection is a primary cause of livestock diarrhea. Therefore, effective vaccines are needed to reduce the incidence of ETEC infection. Objectives: Our study aimed to develop a multivalent ETEC vaccine targeting major virulence factors of ETEC, including enterotoxins and fimbriae. Methods: SLS (STa-LTB-STb) recombinant enterotoxin and fimbriae proteins (F4, F5, F6, F18, and F41) were prepared to develop a multivalent vaccine. A total of 65 mice were immunized subcutaneously by vaccines and phosphate-buffered saline (PBS). The levels of specific immunoglobulin G (IgG) and pro-inflammatory cytokines were determined at 0, 7, 14 and 21 days post-vaccination (dpv). A challenge test with a lethal dose of ETEC was performed, and the survival rate of the mice in each group was recorded. Feces and intestine washes were collected to measure the concentrations of secretory immunoglobulin A (sIgA). Results: Anti-SLS and anti-fimbriae-specific IgG in serums of antigen-vaccinated mice were significantly higher than those of the control group. Immunization with the SLS enterotoxin and multivalent vaccine increased interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) concentrations. Compared to diarrheal symptoms and 100% death of mice in the control group, mice inoculated with the multivalent vaccine showed an 80% survival rate without any symptom of diarrhea, while SLS and fimbriae vaccinated groups showed 60 and 70% survival rates, respectively. Conclusions: Both SLS and fimbriae proteins can serve as vaccine antigens, and the combination of these two antigens can elicit stronger immune responses. The results suggest that the multivalent vaccine can be successfully used for preventing ETEC in important livestock.