• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.175-180
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• 2007

In order to determine the role of Peyer's patch lymphocytes (PPL) in self-clearing of Cryptosporidium parvum infection in murine models, changes in PPL subsets, their cytokine expression, and in vitro IgG1 and IgA secretions by PPL were observed in primary- and challenge-infected C57BL/6 mice. In primary-infected mice, the percentages of CD4+ T cells, CD8+ T cells, slgA+ B cells, IL-2+ T cells, and $IFN-{\gamma}+$ T cells among the PPL, increased significantly (P < 0.05) on day 10 post-infection (PI). Secretion of IgG1 and IgA in vitro by PPL also increased on day 10 PI. However, all these responses, with the exception of IgG1 and IgA secretions, decreased in challenge-infected mice on day 7 post-challenge (= day 13 PI); their IgG1 and IgA levels were higher (P > 0.05) than those in primary-infected mice. The results suggest that murine PPL play an important role in self-clearing of primary C. parvum infections through proliferation of CD4+, CD8+, IL-2+, and $IFN-{\gamma}+$ T cells, and IgG1 and IgA-secreting 8 cells. In challenge infections, the role of T cells is reduced whereas that of 8 cells secreting IgA appeared to be continuously important.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.375-382
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• 2014

The competency of garlic and pennywort to improve broiler chicken growth and influence intestinal microbial communities and fatty acid composition of breast meat were studied. Two hundred forty, "day-old" chicks were randomly allocated to 4 treatment groups consisting of 6 replications of 10 chicks in each pen. The groups were assigned to receive treatment diets as follows: i) basal diet (control), ii) basal diet plus 0.5% garlic powder (GP), iii) basal diet plus 0.5% pennywort powder (PW) and iv) 0.002% virginiamycin (VM). Birds were killed at day 42 and intestinal samples were collected to assess for Lactobacillus and Escherichia coli. The pectoralis profundus from chicken breast samples was obtained from 10 birds from each treatment group on day 42 and frozen at $-20^{\circ}C$ for further analyses. Fatty acid profile of breast muscles was determined using gas liquid chromatography. Feed intake and weight gain of broilers fed with GP, PW, and VM were significantly higher (p<0.05) compared to control. Feeding chicks GP, PW, and VM significantly reduced Escherichia coli count (p<0.05) while Lactobacillus spp count were significantly higher (p<0.05) in the gut when compared to control group on day 42. Supplemented diet containing pennywort increased the C18:3n-3 fatty acid composition of chickens' breast muscle. Garlic and pennywort may be useful in modulating broiler guts as they control the enteropathogens that help to utilize feed efficiently. This subsequently enhances the growth performances of broiler chickens.

• Parasites, Hosts and Diseases
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• v.48 no.4
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• pp.325-329
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• 2010

Toxoplasma gondii KI-1, a recent new isolate from Korea, shows similar pathogenicity and infectivity to mice compared to the virulent RH strain. To understand characteristics of host immunity, including immune enhancement or suppression, we investigated proliferative responses and phenotypes of spleen cells. In addition, kinetics of IFN-${\gamma}$, a Th1 cytokine, was examined in BALB/c mice up to day 6 post-infection (PI). Intraperitoneal injection of mice with $10^3$ KI-1 tachyzoites induced significant decreases (P < 0.05) in proliferative responses of spleen cells. This occurred at days 2-6 PI even when concanavalin A (con A) was added and when stimulated with KI-1 antigen, suggesting suppression of the immunity. $CD4^+$ T-cells decreased markedly at day 2 PI (P < 0.05), whereas $CD8^+$ T-cells, NK cells, and macrophages did not show significant changes, except a slight, but significant, increase of $CD8^+$ T-cells at day 6 PI. The capacity of splenocytes to produce IFN-${\gamma}$ by con A stimulation dropped significantly at days 2-6 PI. These results demonstrate that intraperitoneal injection of KI-1 tachyzoites can induce immunosuppression during the early stage of infection, as revealed by the decrease of $CD4^+$ T-cells and IFN-${\gamma}$.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.315-315
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• 2016

최근 증가하고 있는 수자원의 지속가능성과 수생태계의 복원력 향상에 대한 관심을 반영하여 한반도 8개 다목적댐에 대하여 일유입량, 태풍과 비태풍 강우의 영향을 고려하여 수문학적 거동 특성을 분석하였다. The annual maximum flow(AMF) 와 7-day low flow의 분석결과를 기반으로 극치사상에 대하여 수문학적 인자(magnitude, timing, duration, and frequency)의 경향성분석을 수행하였다. AMF 분석결과, 충주댐, 소양강댐은 봄과 초여름 유입량의 감소경향을 보였다. 섬진강댐 유역은 태풍강우에 가장 민감한 유역이며 빈도와 지속기간에 대하여 통계적으로 유의한 증가 경향을 보였다. 7-day Low Flow 분석결과, 충주댐과 안동댐은 겨울철 유입량에 대하여 감소추세를 보이고 있지만, 태풍의 영향은 잘 나타나지 않는다. 본 연구는 8개 다목적댐 유역의 극치사상과 관련된 다양한 수문학적 변화에 대한 연구를 수행함으로서 유역의 흐름 패턴과 관련된 인과관계를 설명하고, 유역 맞춤형 중 장기 수자원 공급을 위한 기초자료를 제공할 것으로 기대된다.

• Journal of the Korean earth science society
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• v.24 no.1
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• pp.22-29
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• 2003

Temporal and spatial variability of precipitation (P), evaporation (E), and moisture balance (P-E; precipitation minus evaporation) has been investigated over the tropical ocean during the period from January 1998 to July 2001. Our data were analyzed by the EOF method using the satellite P and E observations made by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) and the Special Sensor Microwave/Imager (SSM/I). This analysis has been performed for two three-year periods as follow; The first period which includes the El Ni${\tilde{n}}$o in early 1998 ranges from January 1998 to December 2000, and the second period which includes the La Ni${\tilde{n}}$o events in the early 1999 and 2000 (without El Ni${\tilde{n}}$o) ranges from August 1998 to July 2001. The areas of maxima and high variability in the precipitation and in the P-E were displaced from the tropical western Pacific and the ITCZ during the La Ni${\tilde{n}}$o to the tropical middle Pacific during the El Ni${\tilde{n}}$o, consistent with those in previous P studies. Their variations near the Korean Peninsula seem to exhibit a weakly positive correlation with that in the tropical Pacific during the El Ni${\tilde{n}}$o. The evaporation, out of phase with the precipitation, was reduced in the tropical western Pacific due to humid condition in boreal summer, but intensified in the Kuroshio and Gulf currents due to windy condition in winter. The P-E variability was determined mainly by the precipitation of which the variability was more localized but higher by 2-3 times than that of evaporation. Except for the ITCZ (0-10$^{\circ}$N), evaporation was found to dominate precipitation by ${\sim}$2 mm/day over the tropical Pacific. Annual and seasonal variations of P, E, and P-E were discussed.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.139-148
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• 2000

A mass balance/photochemical modeling approach was used to evaluate the sea-to-air dimethyl sulfide (DMS) fluxes in tropical regions and part of the Southern Ocean. The flux determinations were based on 10 airborne observations by ACE 1 transit flights (i.e., Flights 4-9 and 29-32). The DMS flux values for the tropical regions ranged from 1.0 to 7.4 $\mu$mole/$m^2$/day with an average estimate of 4.2$\pm$2.3 $\mu$mole/$m^2$/day. The seasonal variations in the DMS flux predicted for the equatorial Pacific Ocean based on atmospheric DMS measurements were not entirely consistent with those derived from seawater DMS measurements were not entirely consistent with those derived from seawater DMS measurements reported in previous literature. Inhomogeneities in the DMS flux field were found to cause significant shifts in the atmospheric DMS levels even in the same sampling location. Accordingly, no definitive statement can be made at this stage regarding systematic differences or agreements in the DMS flux estimates from the two approaches. Moreover, this study strongly suggests that DMS oxidation is the most likely dominant source of SO$_2$in tropical regions, which is also supported by another set of compiled observations. Finally, these SO$_2$observations indicate that, when significant data was available for both the boundary and buffer layers, the vertical SO$_2$gradient between these two zones was primarily negative.

• Journal of agricultural medicine and community health
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• v.9 no.1
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• pp.67-73
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• 1984

Albendazole, a new broad spectrum anthelmintic drug, was evaluated for anthelmintic effects in 74 patients with single or mixed infections of Ascaris lumbricoides, Trichuris trichiura. Enterobius vermicularis, Metagonimus yokogawai, Clonorchis sinensis and Taenia spp. Albendazole was administered as a single dose of 400 mg. The cure rate for A. lumbricoides and E. vermicularis was 91.4% and 98.1% respectively at day 30 post-treatment: for T. trichiura it was 51.1% and for M. yakogawai and C. sinensis it was 33.3% and 13.3% respectively. The egg reduction rate at day 30 was 98.5% in A. lumbricoides, 76.5% for T. trichiura : 60.0% for M. yokogawai and 59.6% for C. sinensis However it was not cured in all 5 cases of taeniasis at three months follow-up examination. On the other hand, the various dosages of albendazole were given to the patients infected with C. sinensis and Taenia spp. respectively. The follow-up examinations were carried out at 30 days after treatment in clonorchiasis and at 3 months after treatment in taeniasis. In the results, the recommended dosage of albendazole for clonorchiasis is $3{\times}400mg$ for 3 consecutive days and for taeniasis $2{\times}400mg$ for 3 consecutive days. There were no side effects with the above dosages except only a mild abdominal pain and dizziness in a few patients. Albendazole appears to be more effective than the other available broad spectrum anthelmintic drugs.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.159-164
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• 1994

Two studies were conducted using 40 cross-bred bulls to study the effect of chopping, moistening with water or common salt solution on the nutritive value of rice straw (variety BG-400). Moistening with water did not significantly effect digestibility or intake of rice straw. As compared to straw fed in the long form, chopping did not significantly influence intake (2.33 vs 1.97kg $100kgBW^{-1}day^{-1}$, respectively), but significantly (p<0.05) decreased the digestibility (41.6 vs 37.4%) and intake of digestible dry matter (0.99 vs 0.74kg $100kgBW^{-1}day^{-1}$). Rice straw moistened with 2 or 4% common sea salt solution and directly fed to animals (Exp. 1) did not significantly effect its digestibility (43.9 and 43.1%, respectively) or intake (2.66 or 2.59kg $100kgBW^{-1}day^{-1}$, respectively), but over night storing of 2% salt solution sprayed straw (Exp. 2) significantly reduced its digestibility (33.6%). The latter is difficult to explain because the sodium concentration (mg/g straw dry matter) was lower than 4% salt solution treatment used in experiment 1 (3.30 vs 5.22). It is concluded that chopping, moistening with water or NaCl salt solution did not significantly improve the nutritive value of rice straw.

• Parasites, Hosts and Diseases
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• v.49 no.1
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• pp.45-49
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• 2011

Chemotherapy of clonorchiasis with praziquantel (PZQ) is effective but about 15% of treated cases have been reported uncured. The present study investigated correlation of single nucleotide polymorphisms (SNPs) of the cytochrome P450 gene, CYP3A5 and cure of clonorchiasis. A total of 346 egg passing residents were subjected and treated by 3 doses of 25 mg/kg PZQ. Reexamination recognized 33 (9.5%) uncured and 313 cured. Numbers of eggs per gram of feces (EPGs) before treatment were significantly lower in the cured group than in the uncured group ($2,011.2{\pm}3,600.0$ vs $4,998.5{\pm}7,012.0$, P<0.001). DNAs of the subjects were screened for SNPs at 7 locations of CYP3A5 using PCR. In the uncured group, the SNP frequencies at g.-20555G > A and g.27526C > T of CYP3A5 were 15.2% and 9.1% while those were 3.8% and 1.0%, respectively, in the cured group. The cure rate was Significantly lower in the cases with SNP at g.27526C > T and EPGs ${\geq}$ 1,000. In conclusion, EPGs and SNPs of CYP3A5 are factors which influence cure of clonorchiasis by PZQ therapy. It is strongly suggested to recommend 2-day medication for individuals with high EPGs ${\geq}$ 1,000.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1291-1300
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• 2018

Objective: This experiment was conducted to investigate the effects of dietary crude protein (CP) level and exogenous protease supplementation on growth performance, serum metabolites, carcass traits, small intestinal morphology and endogenous protease activity in broiler chickens reared under a tropical climate. Methods: A total of 480 day-old male broiler chicks were randomly assigned to eight dietary treatments in a $4{\times}2$ factorial arrangement. The main effects were CP level (21.0%, 19.7%, 18.5%, or 17.2% from 1 to 21 days and 19.0%, 17.9%, 16.7%, or 15.6% from 22 to 35 days) and protease enzyme supplementation (0 ppm or 500 ppm). All experimental diets were fortified with synthetic feed-grade lysine, methionine, threonine and tryptophan to provide the minimum amino acid recommended levels for Cobb 500. Results: Reducing dietary CP linearly reduced (p<0.05) growth performance, serum albumin, total protein, and carcass traits and increased (p<0.05) serum triglycerides and abdominal fat. There was no consistent effect of reducing dietary CP on morphological parameters of the intestine and on the pancreatic and intestinal endogenous protease activity (p>0.05). Protease supplementation improved (p<0.05) feed conversion ratio, body weight gain, carcass yield and intestinal absorptive surface area. Conclusion: Protease supplementation, as measured by growth performance, intestinal morphology and carcass yield, may alleviate the detrimental effects of low protein diets in broiler chickens.