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The Importance of Food Open Challenge Test in Atopic Dermatitis: The Comparison of Allergy History, Skin-Prick Test, and Specific IgE Detection

  • Noh, Geun-Woong;Ji, Eun-Jung;Park, Jung-Nan;Kim, Kyung-Hee;Do, Min-Hee;Lee, Eung-Kyung;Lee, Sang-Sun
    • Nutritional Sciences
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    • v.2 no.2
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    • pp.119-124
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    • 1999
  • Food allergies play an important role in Atopic Dermatitis (AD). Dietary manipulation is essential in the management of AD. However, there has been a paucity of data reporting the prevalence of food allergies in AD patients in Korea. In this study, the Food Open Challenge Tests (FOCT) were conducted to investigate food allergies in AD patients. The skin-prick test and the detection of specific IgE, as well as allergy history of patient were used to detect food allergies in all AD patients. Elimination diet was conducted for two weeks prior to FOCTs. The prevalence of food allergies by FOCT is as follows: milk (67.3%); chicken (64.2%); pork (62.8%); eggs (61.0%); beef(55.4%) ; wheat (52.0%) and soybean (45.2%). Allergenic food items in Korean AD patients were different from people in other foreign countries. The seven major foods those tested positively by FOCTs were completely eliminated from the replaced diets for two weeks, and were subsequently reintroduced one at a time. Results from FOCTs were not comparable with allergy history or skin-prick tests or specific IgE detection. The sensitivity and specificity of skin-prick tests and specific IgE detection were lower than FOCTs. Allergy history, skin-prick tests, and specific IgE detection are useful for the identification of food allergen but its clinical significance differed according to food items. Therefore, we conclude that even though a 10-day delay was necessary after food challenge, FOCT is a useful and valid method to confirm food allergies and may be essential for the effective control of food allergies for treatment of AD.

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Construction and Immunogenicity of Recombinant Swinepox Virus Expressing Outer Membrane Protein L of Salmonella

  • Fang, Yizhen;Lin, Huixing;Ma, Zhe;Fan, Hongjie
    • Journal of Microbiology and Biotechnology
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    • v.26 no.7
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    • pp.1173-1181
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    • 2016
  • Salmonella spp. are gram-negative flagellated bacteria that cause a variety of diseases in humans and animals, ranging from mild gastroenteritis to severe systemic infection. To explore development of a potent vaccine against Salmonella infections, the gene encoding outer membrane protein L (ompL) was inserted into the swinepox virus (SPV) genome by homologous recombination. PCR, western blot, and immunofluorescence assays were used to verify the recombinant swinepox virus rSPV-OmpL. The immune responses and protection efficacy of rSPV-OmpL were assessed in a mouse model. Forty mice were assigned to four groups, which were immunized with rSPV-OmpL, inactive Salmonella (positive control), wild-type SPV (wtSPV; negative control), or PBS (challenge control), respectively. The OmpL-specific antibody in the rSPV-OmpL-immunized group increased dramatically and continuously over time post-vaccination, and was present at a significantly higher level than in the positive control group (p < 0.05). The concentrations of IFN-γ and IL-4, which represent Th1-type and Th2-type cytokine responses, were significantly higher (p < 0.05) in the rSPV-OmpL-vaccinated group than in the other three groups. After intraperitoneal challenge with a lethal dose of Salmonella typhimurium CVCC542, eight out of ten mice in the rSPV-OmpL-vaccinated group were protected, whereas all the mice in the negative control and challenge control groups died within 3 days. Passive immune protection assays showed that hyperimmune sera against OmpL could provide mice with effective protection against challenge from S. typhimurium. The recombinant swinepox virus rSPV-OmpL might serve as a promising vaccine against Salmonella infection.

Effect of Airborne Organic Vapor Concentration Levels on the Adsorption Capacity of Charcoal in the Cartridges of Air Purifying Respirators (공기 중 유기용제 농도수준이 방독마스크 정화통의 활성탄 흡착용량에 미치는 영향)

  • Park, Doo-Yong
    • Journal of Environmental Health Sciences
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    • v.37 no.1
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    • pp.50-56
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    • 2011
  • The adsorption capacity of charcoal is a function of the airborne concentration of the target chemical. To evaluate the adsorption capacity of charcoal packed in the cartridges of air purifying respirators, breakthrough tests were conducted with carbon tetrachloride for three commercial cartridges (3M models #7251, #6000 and AX) at 25, 50, 100, 250 and 500 ppm. Adsorption capacities were calculated using a mass transfer balance equation derived from the curve fitting to the breakthrough curves obtained experimentally. Carbon micropore volumes were estimated by iteration to fit the Dubinin/Radushkevich (D/R) adsorption isotherm. They were 0.6566, 0.5727 and 0.3087 g/cc for #7251, #6000 and the AX cartridge, respectively. Above 100 ppm (at high challenge concentrations), #7251 and #6000 showed higher adsorption capacities. However, as the challenge concentration decreased, the adsorption capacities of #7251 and #6000 sharply dropped. On the other hand, the adsorption capacity of the AX cartridge showed little change with the decrease of the challenge concentration. Thus, the AX showed a higher adsorption capacity than #7251 and #6000 at the 5-50 ppm level. It is concluded that service-life tests of cartridges and adsorption capacity tests of charcoal should be conducted at challenge concentration levels reflecting actual working environmental conditions. Alternatively, it is recommended to use the D/R adsorption isotherm to extrapolate adsorption capacity at low concentration levels from the high concentration levels at which breakthrough tests are conducted, at a minimum of two different concentration levels.

A Session Key Exchange Scheme for Authentication and SDP Encryption to Protect P2P SPIT in SIP (SIP P2P 스팸 방지를 위한 인증 및 SDP 암호화 키 교환 기법)

  • Jang, Yu-Jung;Choi, Jae-Sic;Choi, Jae-Duck;Won, Yoo-Jae;Cho, Young-Duk;Jung, Sou-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.12B
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    • pp.750-757
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    • 2007
  • This paper analyzes spam threats and proposes key exchange scheme for user authentication and SDP encryption to protect potential spam threats in SIP-based VoIP services. The existing HTTP digest authentication scheme exchanges many message because challenge is sent for every establishment of the session and doesn't provide a confidentiality of SDP. To protect SPIT, our scheme exchanges initial nonce and a session master key for authentication and SDP encryption during registration. In our scheme, the challenge and response procedure is not necessary and the communication overhead is much less than applying S/MIME or TLS.

Smartphone Ownership and Location Checking Scheme for Fixing the Vulnerabilities of SMS-Based Authentication (SMS 기반 인증의 보안 취약점을 개선한 스마트폰 소유 및 위치 확인 기법)

  • Kwon, Seong-Jae;Park, Jun-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.42 no.2
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    • pp.349-357
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    • 2017
  • Many Web sites adopt SMS(Short Message Service)-based user authentication when a user loses her password or approves an online payment. In SMS-based authentication, the authentication server sends a text in plaintext to a user's phone, and it allows an attacker who eavesdrops or intercepts the text to impersonate a valid user(victim). We propose a challenge-response scheme to prove to the authentication server that a user is in a certain place at the moment with her smartphone beside her. The proposed scheme generates a response using a challenge by the server, user's current location, and a secret on the user's smartphone all together. Consequently, the scheme is much more secure than SMS-based authentication that simply asks a user to send the same text arrived on her phone back to the server. In addition to entering the response, which substitutes the SMS text, the scheme also requests a user to input a passphrase to get the authentication process started. We believe, however, the additional typing should be tolerable to most users considering the enhanced security level of the scheme.

Food Protein-induced Enterocolitis Syndrome: an Update on Clinical Approaches and Its Pathophysiology (식품 단백질 유발성 장염 증후군: 임상적 접근과 병태생리의 최신 지견)

  • Hwang, Jin-Bok
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.10 no.2
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    • pp.117-128
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    • 2007
  • Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE mediated hypersensitivity disorder, which is associated with mainly gastrointestinal symptoms and has a delayed onset. The vomiting and/or diarrheal symptoms of FPIES typically begin in the first month of life in association with a failure to thrive, metabolic acidosis, and shock. Therefore, the differential diagnosis of FPIES and neonatal or infantile sepsis-like illnesses or gastroenteritis is difficult. The early recognition of indexes of suspicion for FPIES may help in the diagnosis and treatment of this disorder. The diagnosis of FPIES is generally made through clinical practice and food-specific IgE test findings are typically negative in this condition. Therefore, oral cow's milk challenge (OCC) remains the valid diagnostic standard for FPIES. An investigation of positive OCC outcomes helps to find out a diagnostic algorithm of criteria of a positive challenge in FPIES. Moreover, it has not been clearly determined in infantile FPIES when $1^{st}$ follow up-oral food challenge (FU-OFC) should be performed, with what kind of food protein (e.g., cow's milk, soy), and how much protein should be administered. Hence, to prevent the risk of inappropriate FU-OFC or accidental exposure and achieve appropriate dietary management, it is necessary to identify tolerance rates to major foods under the careful follow up of infantile FPIES patients. On the other hand, small intestinal enteropathy with villous atrophy is observed in FPIES and this enteropathy seems to be in part induced by both of epithelial apoptosis and intercellular junctional complex breakdown. The purpose of this report is to introduce an update on diagnostic and therapeutic approaches in FPIES and suggest the possible histopathological evidences in this disorder.

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Effect of Lipopolysaccharide (LPS) Exposure on the Reproductive Organs of Immature Female Rats

  • Yoo, Da Kyung;Lee, Sung-Ho
    • Development and Reproduction
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    • v.20 no.2
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    • pp.91-99
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    • 2016
  • Lipopolysaccharide (LPS), an endotoxin, elicits strong immune responses in mammals. Several lines of evidence demonstrate that LPS challenge profoundly affects female reproductive function. For example, LPS exposure affects steroidogenesis and folliculogenesis, resulting in delayed puberty onset. The present study was conducted to clarify the mechanism underlying the adverse effect of LPS on the delayed puberty in female rats. LPS was daily injected for 5 days ($50{\mu}g/kg$, PND 25-29) to treated animals and the date at VO was evaluated through daily visual examination. At PND 39, animals were sacrificed, and the tissues were immediately removed and weighed. Among the reproductive organs, the weights of the ovaries and oviduct from LPS-treated animals were significantly lower than those of control animals. There were no changes in the weights of uterus and vagina between the LPS-treated and their control animals. immunological challenge by LPS delayed VO. Multiple corpora lutea were found in the control ovaries, indicating ovulations were occurred. However, none of corpus luteum was present in the LPS-treated ovary. The transcription level of steroidogenic acute regulatory protein (StAR), CYP11A1, CYP17A1 and CYP19 were significantly increased by LPS treatment. On the other hand, the levels of $3{\beta}$-HSD, $17{\beta}$-HSD and LH receptor were not changed by LPS challenge. In conclusion, the present study demonstrated that the repeated LPS exposure during the prepubertal period could induce multiple alterations in the steroidogenic machinery in ovary, and in turn, delayed puberty onset. The prepubertal LPS challenge model used in our study is useful to understand the reciprocal regulation of immune (stress) - reproductive function in early life.

Effects of Dietary Additives and Early Feeding on Performance, Gut Development and Immune Status of Broiler Chickens Challenged with Clostridium perfringens

  • Ao, Z.;Kocher, A.;Choct, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.541-551
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    • 2012
  • The effects of dietary additives and holding time on resistance and resilience of broiler chickens to Clostridium perfringens challenge were investigated by offering four dietary treatments. These were a negative control (basal), a positive control (Zn-bacitracin) and two dietary additives, mannanoligosaccharides (MOS), and acidifier. Two holding times included (a) immediate access to feed and water post hatch (FED) and (b) access to both feed and water 48 h post hatch (HELD). Chicks fed Zn-bacitracin had no intestinal lesions attributed to necrotic enteritis (NE), whereas chicks fed both MOS or acidifier showed signs of NE related lesions. All dietary treatments were effective in reducing the numbers of C. perfringens in the ileum post challenge. The FED chicks had heavier body weight and numerically lower mortality. The FED chicks also showed stronger immune responses to NE challenge, showing enhanced (p<0.05) proliferation of T-cells. Early feeding of the MOS supplemented diet increased (p<0.05) IL-6 production. The relative bursa weight of the FED chicks was heavier at d 21 (p<0.05). All the additives increased the relative spleen weight of the HELD chicks at d 14 (p<0.05). The FED chicks had increased villus height and reduced crypt depth, and hence an increased villus/crypt ratio, especially in the jejunum at d 14 (p<0.05). The same was true for the HELD chicks given dietary additives (p<0.05). It may be concluded that the chicks with early access to dietary additives showed enhanced immune response and gut development, under C. perfringens challenge. The findings of this study shed light on managerial and nutritional strategies that could be used to prevent NE in the broiler industry without the use of in-feed antibiotics.

Effects of Citro Reticulatae Viride Pericarpium on the Vascular Endothelial Growth Factor(VEGF) in the bronchial asthma mouse model (청피(靑皮)가 천식유발 백서에서 VEGF에 미치는 영향)

  • Lee, Hai-Ja
    • The Journal of Pediatrics of Korean Medicine
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    • v.20 no.1
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    • pp.181-194
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    • 2006
  • Objective : Author evaluate the effects of Citri Reticulatae Viride Pericarpium for the bronchial asthma using assesment of the vascular endothelial growth factor after Citri Reticulatae Viride Peicarpium was intravenously administered Ovalbumine(OVA)-sensitized and -challenged mice. Material and Methods : Twenty-four female mice, 8-10 weeks old and free of murine specific pathogens, were sensitized by intraperitoneal injection of OVA. Of the sensitized mice, ten mice didn't administrate Citri Reticulatae Viride Pericarpium and the other ten mice administrated Citri Reticulatae Viride Pericarpium. Mice were sensitized on the first and fourteen days introspectional injection of 20 ${\mu}g$ OVA. After$21^{st}\;22^{th}\;and\;23^{rd}$, the initial sensitization, the mice were challenged for 30 minutes with an aerosol of 1% OVA in saline. Citri Reticulatae Viride Pericarpium administered 200mg/kg in the tail of the mouse, one a day, for 7 days and beginning 14 days after first sensitization. Bronchoalveolar lavage was performed 72 hours after the last challenge, and total cell numbers in the BAL fluid were count. Also, lever of VEGF in the BAL fluid was measured by Enzyme immunoassays and Western blot analysis. Results: Total cell numbers in BAL fluid were significantly greater than from 72 hrs after OVA inhalation compared with cell numbers in the control group. However, there was no difference of the total cell numbers between OVA-challenge groups without Citri Reticulatae Viride Pericarpium, and OVA-challenge with Citri Reticulatae Viride Pericarpium. Enzyme immunoassay revealed that VEGF levels in the BAL fluids were significantly increased 72 hrs after OVA inhalation compared with levels in the control group. After administration of the Citri Reticulatae Viride Pericarpiu, the levels of the VEGF in BAL fluids 72 hrs after OVA inhalation reduced dramatically. Western blot analysis revealed that VEGF protein levels were increased in the all mice which were challenge with OVA, without administered Citri Reticulatae Viride Pericarpium, compared the normal mouse. However, in the groups of the administered Citri Reticulatae Viride Pericarpium, the VEGF protein level markedly decreased. Conclusion: Citri Reticulatae Viride Pericarpium might affect the treatment of the bronchial ashma as a inhibition of the VEGF.

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Oral food challenges in children

  • Yum, Hye-Yung;Yang, Hyeon-Jong;Kim, Kyung-Won;Song, Tae-Won;Kim, Woo-Kyung;Kim, Jung-Hee;Ahn, Kang-Mo;Kim, Hyun-Hee;Lee, Soo-Young;Pyun, Bok-Yang
    • Clinical and Experimental Pediatrics
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    • v.54 no.1
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    • pp.6-10
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    • 2011
  • Many patients assume that allergic reactions against foods are responsible for triggering or worsening their allergic symptoms. Therefore, it is important to identify patients who would benefit from an elimination diet, while avoiding unnecessary dietary restrictions. The diagnosis of food allergy depends on the thorough review of the patients's medical history, results of supplemented trials of dietary elimination, and in vivo and in vitro tests for measuring specific IgE levels. However, in some cases the reliability of such procedures is suboptimal. Oral food challenges are procedures employed for making an accurate diagnosis of immediate and occasionally delayed adverse reactions to foods. The timing and type of the challenge, preparation of patients, foods to be tested, and dosing schedule should be determined on the basis of the patient's history, age, and experience. Although double-blind, placebo-controlled food challenges(DBPCFC) are used to establish definitively if a food is the cause of adverse reactions, they are time-consuming, expensive and troublesome for physician and patients. In practice, An open challenge controlled by trained personnel is sufficient especially in infants and young children. The interpretation of the results and follow-up after a challenge are also important. Since theses challenges are relatively safe and informative, controlled oral food challenges could become the measure of choice in children.