• Parasites, Hosts and Diseases
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• 제53권5호
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• pp.561-569
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• 2015

Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ${\geq}15years$. We found significant increases in respondents' knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents' knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections.

• Parasites, Hosts and Diseases
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• 제52권3호
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• pp.273-280
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• 2014

The changing patterns of goblet cell hyperplasia, intestinal epithelial cell turnover, and intestinal motility were studied in ICR and C57BL/6 mice infected with Gymnophalloides seoi (Digenea: Gymnophallidae). Whereas ICR mice retained G. seoi worms until day 7 post-infection (PI), C57BL/6 mice showed a rapid worm expulsion within day 3 PI. Immunosuppression with Depo-Medrol significantly delayed the worm expulsion in C57BL/6 mice. Goblet cell counts were increased in both strains of mice, peaking at day 1 PI in C57BL/6 mice and slowly increasing until day 7 PI in ICR mice. In C57BL/6 mice infected with G. seoi, newly proliferating intestinal epithelial cells were remarkably increased in the crypt, and the increase was the highest at day 1 PI. However, in ICR mice, newly proliferating intestinal epithelial cells increased slowly from day 1 to day 7 PI. Intestinal motility was increased in G. seoi-infected mice, and its chronological pattern was highly correlated with the worm load in both strains of mice. Meanwhile, immunosuppression of C57BL/6 mice abrogated the goblet cell proliferation, reduced the epithelial cell proliferation, and suppressed the intestinal motility. Goblet cell hyperplasia, increased intestinal epithelial cell turnover, and increased intestinal motility should be important mucosal defense mechanisms in G. seoi-infected C57BL/6 mice.

• Parasites, Hosts and Diseases
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• 제41권2호
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• pp.81-87
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• 2003

The effects of anti-allergic drugs on intestinal mastocytosis and the expulsion of Neodiplostomum seoulense were observed in Sprague-Dawley rats, after oral infection with 500 metacercariae. The drugs used were hydroxyzine (a histamine receptor H$_1$ blocker), cimetidine (a H$_2$ blocker), cyclosporin-A (a helper T-cell suppressant), and prednisolone (a T- and B-cell suppressant). Infected, but untreated controls, and uninfected controls, were prepared. Worm recovery rate and intestinal mastocytosis were measured on weeks 1, 2, 3, 5, and 7 post-infection. Compared with the infected controls, worm expulsion was significantly (P < 0.05) delayed in hydroxyzine- and cimetidine-treated rats, despite mastocytosis being equally marked in the duodenum of all three groups. In the cyclosporin-A- and prednisolone-treated groups, mastocytosis was suppressed, but worm expulsion was only slightly delayed, without statistical significance. Our results suggest that binding of histamine to its receptors on intestinal smooth muscles is more important in terms of the expulsion of N. seoulense from rats than the levels of histamine alone, or mastocytosis.

• Parasites, Hosts and Diseases
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• 제47권3호
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• pp.315-318
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• 2009

Quantitative fecal egg counts represented as the number of eggs per gram of feces (EPG) are generally a reliable parameter to estimate the worm burden of intestinal and hepatic parasitoses. Although Haplorchis taichui (Digenea: Heterophyidae) is one of the most common minute human intestinal flukes, little is known about the relationship between EPG and the actual worm burden in patients or the severity of the disease. In the present study, fecal samples were collected from 25 villagers in northern Thailand before and after praziquantel treatment. The EPG values of each participant were determined by the modified cellophane thick smear method, and adult worms were collected from the whole stool after the treatment. Eggs per day per worm (EPDPW) of H. taichui were estimated 82 from egg counts and expelled worms. The EPG was not well correlated with the worm burden, and a reverse correlation was observed between the EPDPW and the worm burden.

• Parasites, Hosts and Diseases
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• 제51권5호
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• pp.589-594
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• 2013

In intestinal helminth infections, Th2 immune respones are generally associated with mucin secretion for worm expulsion from the host intestine. In particular, IL-4 and IL-13 are the important cytokines related with intestinal mucus production via STAT6 signalling in nematode infections. However, this perspective has never been studied in Gymnophalloides seoi infection. The present study aimed to observe the STAT6 signalling and cytokine responses in C57BL/6 mice, a mouse strain resistant to infection with this trematode. The results showed that worm expulsion occurred actively during days 1-2 post-infection (PI), when goblet cells began to proliferate in the small intestine. The STAT6 gene expression in the mouse spleen became remarkable from day 2 PI. Moreover, G. seoi infection induced a significant increase of IL-13 from day 4 PI in the spleen of infected mice. Our results suggested that goblet cell hyperplasia and worm expulsion in G. seoi-infected mice should be induced by STAT6 signalling, in which IL-13 may be involved as a dominant triggering cytokine.

• Parasites, Hosts and Diseases
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• 제27권2호
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• pp.109-118
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• 1989

폐흡충 감염시 숙주 말초혈액에는 많은 항체가 생성되므로 각종 면역학적 진단에 이용되 고 있다. 그러나 이들 항체가 폐흡충 충체 구성 요소 중 주로 어느 기관(또는 구조물)에 대한 항체 인지에 대해서는 별로 연구된 바 없었다. 이 연구는 면역 조직화학적 방법을 이용하여 폐흡충 충체 의 부위별 항원성을 파악하기 위한 것으로 충체 절편 표본에서 흡반, 표피, 피극, 난황선, 장, 자성 및 웅성 생식기, 충란 등의 항원성을 비교 관찰한 것이다. 충체 표본으로는 감염 11∼20주 된 고양이의 폐조직에서 충낭(WOrm capsule)을 적출하여 포르말 린 고정 및 파라핀 포매한 것을 4㎛ 두께로 영아 사용하였고, 항혈청(1차 항체)으로 감염 11∼20 주 된 고양이 혈청을, 2차 항체로 peroxidase-conjugated goat anti-cat IgG를 사용하는 간접 면역 대소 염색법(indirect immunoperoxidase staining technique)을 이용하였고, 진한 황색 또는 황갈색으로 염색되면 양성으로 판정하였다. 항체의 희석 농도는 1차 항체 1 : 500~1 : 2,000, 2차 항체 1 : 200~1 : 500으로 하였고 10회 이상 반복 염색하였다. 실험 결과 장 상피의 표면(intestinal epithelial border), 장 내용물, 난황선(vitelline glands) 및 충낭 내의 충란(eggs in worm capsule) 등이 강한 양성 반응을 보였고 자궁 내 충란 및 충체 실질 조직 중 일부도 약하지만 양성 반응을 보였다. 한편 흡반(suckers), 표피(tegument), 피극(spines), 표피하세포(subtegumental cells), 장 상피세포의 세포질, 웅성 생식기관 및 난소 등은 음성 반응 을 나타내었다. 항원성의 강도를 순서대로 나열해보면 장 상피의 표면, 장 내용물, 충낭 내의 충란, 난황선, 자궁 내 충란, 충체 실질조직의 순이었다. 항원성이 강한 장 상피층 및 장 내용물은 1차 항체 1 : 4,000(2차 항체 1 : 200)에서도 양성 반응을 보였으나 충체 실질조직 중 일부는 1차 항체 1 : 500의 고농도(2차 항체 1 : 200)에서만 양성 반응을 보였다. 이상의 결과를 종합해 볼 때, 폐흡충 감염시 나타나는 혈청의 항체 반응은 충체의 배설물과 충 낭 주위에 산출된 충란에 의해 가장 강력히 유발되는 것이 아닌가 생각되며 이들이 충낭을 벗어나 숙주 조직으로 총수되는 가장 중요한 항원성 물질이 아닌가 추측된다.

• Parasites, Hosts and Diseases
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• 제53권5호
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• pp.553-559
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• 2015

Research on micro-level assessment of the changes of socio-economic status following health interventions is very scarce. The use of household asset data to determine wealth indices is a common procedure for estimating socio-economic position in resource poor settings. In such settings information about income is usually lacking, and the collection of individual consumption or expenditure data would require in-depth interviews, posing a considerable risk of bias. In this study, we determined the socio-economic status of 213 households in a community population in an island in the north-western Tanzania before and 3 year after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention to control schistosomiasis and intestinal worm infections. We constructed a household 'wealth index' based housing construction features (e.g., type of roof, walls, and floor) and durable assets ownership (e.g., bicycle, radio, etc.). We employed principal components analysis and classified households into wealth quintiles. The study revealed that asset variables with positive factor scores were associated with higher socio-economic status, whereas asset variables with negative factor scores were associated with lower socio-economic status. Overall, households which were rated as the poorest and very poor were on the decrease, whereas those rated as poor, less poor, and the least poor were on the increase after PHAST intervention. This decrease/increase was significant. The median shifted from -0.4376677 to 0.5001073, and the mean from -0.2605787 (SD; 2.005688) to 0.2605787 (SD; 1.831199). The difference in socio-economic status of the people between the 2 phases was highly statistically significant (P<0.001). We argue that finding of this study should be treated with caution as there were other interventions to control schistosomiasis and intestinal worm infections which were running concurrently on Kome Island apart from PHAST intervention.

• 대한의생명과학회지
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• 제12권4호
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• pp.329-335
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• 2006

Echinostoma hortense (E. hortense) is an intestinal trematode with the highest infection rate in South Korea. However, the immune response against E. hortense infection has not been explained well. In the present study, we investigated the effect of treatment with cyclosporin A (CsA) and histamine receptor antagonists on the cytokine expression and mucosal goblet cells in E. hortense-infected C3H/HeN mice. The alteration of cytokine mRNA expression ($TNF-{\alpha},\;IL-l{\beta},\;IL-4\;and\;IL-5$), intestinal worm recovery rate and goblet cell responses were measured weekly from 0 to 5 weeks post-infection (P.I.) in the control and the following three drug-treated groups: CsA, hydroxyzine and cimetidine. Compared with the control group, the expression of $TNF-{\alpha}$, IL-4 and IL-5 mRNAs decreased in the CsA- and hydroxyzine-treated groups, but only IL-4 mRNA expression did in the cimetidine-treated group. Worm recovery rate was significantly increased in the drug-treated groups. Mucosal goblet cells and their mucin response significantly decreased in the CsA-treated group (P<0.01), but significantly increased in the cimetidine- (P<0.05) and hydroxyzine- (P<0.01) treated groups. These data suggest that CsA treatment inhibits production of Th1- and Th2-type cytokines which are necessary for the worm expulsion. Histamine receptor increases goblet cells and their mucin activation, although it remains to be elucidated whether it directly affects the worm expulsion period of E. hortense in C3H/HeN mice.

• Parasites, Hosts and Diseases
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• 제48권2호
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• pp.133-138
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• 2010

Infection status of intestinal flukes was investigated in residents of Muan-gun, Jeollanam-do, the Republic of Korea. Total 1,257 fecal samples of residents were examined by formalin-ether sedimentation technique and Kato-Katz thick smear method. Helminth eggs were detected from 95 (7.6%) residents, and eggs of heterophyid flukes and Clonorchis sinensis were found from 62 (4.9%) and 40 (3.2%) cases, respectively. The larger heterophyid eggs, somewhat darkbrown in color and $37.7{\times}21.5{\mu}m$ in average size, and found in 32 (2.6%) out of 62 egg positive cases of heterophyid flukes. To confirm the adult flukes, we performed worm recovery from 12 cases after praziquantel treatment and purgation with $MgSO_4$. A total of 1,281 adult flukes, assigned to 7 species, were recovered from 9 cooperative cases. Heterophyes nocens (total 981 specimens) was collected from 9 cases, Stictodora fuscata (80) from 7, Gymnophalloides seoi (75) from 5, Pygidiopsis summa (140) from 3, Stellantchasmus falcatus (3) from 2, and Stictodora lari and Acanthotrema felis (each 1 worm) from 1 case each. The intrauterine eggs of S. fuscata collected from the recovered worm were identical with the larger heterophyid eggs detected in the stool examination. By the present study, it was confirmed that A. felis is a new intestinal fluke infecting humans, and residents in Muan-gun, Jeollanam-do are infected with variable species of intestinal trematodes.

• Parasites, Hosts and Diseases
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• 제52권1호
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• pp.27-33
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• 2014

Mucosal immune responses against Pygidiopsis summa (Trematoda: Heterophyidae) infection were studied in ICR mice. Experimental groups consisted of group 1 (uninfected controls), group 2 (infection with 200 metacercariae), and group 3 (immunosuppression with Depo-Medrol and infection with 200 metacercariae). Worms were recovered in the small intestine at days 1, 3, 5, and 7 post-infection (PI). Intestinal intraepithelial lymphocytes (IEL), mast cells, and goblet cells were counted in intestinal tissue sections stained with Giemsa, astra-blue, and periodic acid-Schiff, respectively. Mucosal IgA levels were measured by ELISA. Expulsion of P. summa from the mouse intestine began to occur from days 3-5 PI which sustained until day 7 PI. The worm expulsion was positively correlated with proliferation of IEL, mast cells, goblet cells, and increase of IgA, although in the case of mast cells significant increase was seen only at day 7 PI. Immunosuppression suppressed all these immune effectors and inhibited worm reduction in the intestine until day 7 PI. The results suggested that various immune effectors which include IEL, goblet cells, mast cells, and IgA play roles in regulating the intestinal mucosal immunity of ICR mice against P. summa infection.