• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.199-208
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• 1987

The chemotherapeutic efficacy of trimethoprim-sulfamethoxazole ($Bactrim^{\circledR}$) in mice experimentally infected with Toxoplasma gcndii was evaluated. The average survival days and survival rate of mice infected intraperitoneally with $1{\times}10^5$ trophozoites and treated with $Bactrim^{\circledR}$ were compared with those of untreated group. The hematologic findings of blood samples of experimental mice were observed for comparison of side elects between $Bactrim^{\circledR}$ and pyrimethamine ($Daraprim^{\circledR}$), the latter of which has been one of the favorable drugs for the treatment of toxoplasmosis. The results are summarized as follows: 1. $Bactrim^{\circledR}$ showed a strong evidence of potent anti-Toxoplasma activity. The survival rate of mice administered with 24 mg of $Bactrim^{\circledR}$ per mouse per day for 7 days, was 83.3%, and the rate was increased to 100% in mice administered with two-fold concentrated dose of the drug. 2. The average numbers of white blood cells (W.B.C.) in the mouse groups treated with $Bactrim^{\circledR}$ or $Daraprim^{\circledR}$ were more increased than those only infected with T. gondii. The mice treated with $Daraprim^{\circledR}$ however, showed remarkably decreased numbers of W.B.C. as compared with those treated with $Bactrim^{\circledR}$ . 3. The average numbers of red blood cells (R.B.C.) and platelets both in the drug-treated and untreated T. gondii-infected mice were decreased as compared with normal mice. The numbers of R. B. C. in $Daraprim^{\circledR}-treated$ mice, however, were more decreased than in $Bactrim^{\circledR}-treated$ mice. 4. The average levels of hemoglobin both in the drug.treated and untreated T. gondii-infected mice were decreased, compared with normal mice. But there was no difference in the levels of hemoglobin between $Bactrim^{\circledR}$ and $Daraprim^{\circledR}-treated$ groups. In conclusion, trimethoprim.sulfamethoxasole ($Bactrim^{\circledR}$) was proven to be effective and safe for the treatment of murine toxoplasmosis. The efficacy was comparable with pyrimethamine ($Daraprim^{\circledR}$), but bone marrow depression was less severe with $Bactrim^{\circledR}$ treatment.

• Parasites, Hosts and Diseases
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• v.53 no.2
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• pp.227-232
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• 2015

Genetic polymorphisms of pvdhfr and pvdhps genes of Plasmodium vivax were investigated in 83 blood samples collected from patients in the Philippines, Bangladesh, and Nepal. The SNP-haplotypes of the pvdhfr gene at the amino acid positions 13, 33, 57, 58, 61, 117, and 173, and that of the pvdhps gene at the positions 383 and 553 were analyzed by nested PCR-RFLP. Results suggest diverse polymorphic patterns of pvdhfr alone as well as the combination patterns with pvdhps mutant alleles in P. vivax isolates collected from the 3 endemic countries in Asia. All samples carried mutant combination alleles of pvdhfr and pvdhps. The most prevalent combination alleles found in samples from the Philippines and Bangladesh were triple mutant pvdhfr combined with single mutant pvdhps allele and triple mutant pvdhfr combined with double wild-type pvdhps alleles, respectively. Those collected from Nepal were quadruple mutant pvdhfr combined with double wild-type pvdhps alleles. New alternative antifolate drugs which are effective against sulfadoxine-pyrimethamine (SP)-resistant P. vivax are required.

• Parasites, Hosts and Diseases
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• v.52 no.6
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• pp.621-629
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• 2014

Malaria is one of the most widespread infectious diseases of tropical countries with an estimated 207 million cases globally. In India, there are endemic pockets of this disease, including Aligarh. Hundreds of Plasmodium falciparum and P. vivax cases with severe pathological conditions are recorded every year in this district. The aim of this study is to find out changes in liver enzymes and kidney markers. Specific diagnosis for P. falciparum and P. vivax was made by microscopic examination of Giemsa stained slides. Clinical symptoms were observed in both of these infections. Liver enzymes, such as AST, ALT, and ALP, and kidney function markers, such as creatinine and urea, were estimated by standard biochemical techniques. In Aligarh district, P. vivax, P. falciparum, and mixed infections were 64%, 34%, and 2%, respectively. In case of P. falciparum infection, the incidences of anemia, splenomegaly, renal failure, jaundice, and neurological sequelae were higher compared to those in P. vivax infection. Recrudescence and relapse rates were 18% and 20% in P. falciparum and P. vivax infections, respectively. Liver dysfunctions and renal failures were more common in P. falciparum patients, particularly in elderly patients. Artesunate derivatives must, therefore, be introduced for the treatment of P. falciparum as they resist to chloroquine as well as sulfadoxine-pyrimethamine combinations.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.309-311
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• 2007

Supramolecules containing double hydrogen bonding sites at their both chain ends were self-polymerized to become solid state polymer and were utilized to improve the efficiency of solid state DSSCs. Hydrogen bonding sites were attached at the chain ends of PEG of Mw=2000, such as pyrimethamine and glutaric acid. The solar cell with the solid state supramolecular polymer electrolyte resulted in the overall energy conversion efficiency of 4.63 % with a short circuit current density $(J_{sc})$ of 10.41 $mAcm^{-2}$, an open circuit voltage $V_{oc}$, of 0.71 V and a fill factor (FF) of 0.62 at one sun condition ([oligomer]:[1-methyl-3-propyl imidazolium iodide (MPII)]:$[I_2]$ = 20 : 1 : 0.19, active area = 0.16 $cm^2$, $TiO_2$ layer thickness = 10 ${\mu}m$). The ionic conductivity of the sol id state electrolyte was $5.11{\times}10^{-4}$ (S/cm). The cell performance was characterized by electrochemical impedance spectroscopy and ionic conductivity.

• Parasites, Hosts and Diseases
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• v.52 no.4
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• pp.439-441
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• 2014

Toxoplasma gondii is the causative agent of toxoplasmosis with symptoms of congenital neurological and ocular diseases and acquired lymphadenitis, retinochoroiditis, and meningoencephalitis. Small molecules which block the activity of protein kinases were tested in in vitro culture of T. gondii to find new therapeutic drugs of safer and more effective than the combined administration of pyrimethamine and sulfadoxine that sometimes provoke lethal Stevens-Johnson syndrome. Among them, Gefitinib and Crizotinib inhibited intracellular growth of T. gondii in HeLa cells by counting the number of T. gondii per parasitophorous vacuolar membrane whereas Sunitinib did not. Gefitinib inhibited the growth of T. gondii in a dose-dependent manner over $5{\mu}M$ up to the tolerable concentration of HeLa cells and halted the division of the parasite immediately from the time point of treatment. Gefitinib inhibition suggests that tyrosine kinases of EGFR family or other homologous kinases of the parasite itself may be the target to cause the block of T. gondii growth.

• Korean Journal of Veterinary Service
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• v.37 no.2
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• pp.101-104
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• 2014

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, with very few therapeutic treatment options. The choices for treatment are pyrimethamine and sulfadiazine, however their utility is limited because of drug toxicity and serious side effects. In this study, ethanol extracts of 13 traditional medicines used to treat Toxoplasma gondii were tested in vitro for their anti-Toxoplasma gondii cytotoxicity. The median effective concentration ($EC_{50}$) values for the herbal extracts ranged from 173 mg/mL to 1995.35 mg/mL. In HeLa cell, the selectivity of Alpinia oxyphylla (2.75), Mucunae Caulis (2.96), Dictamnus dasycarpus (7.52) which was higher than sulfadiazine (2.08). This indicates that Alpinia oxyphylla, Mucunae Caulis, Dictamnus dasycarpus extracts may be sources of new anti-Toxoplasma gondii compounds.

• YAKHAK HOEJI
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• v.59 no.6
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• pp.266-269
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• 2015

Coccidiosis is induced by Toxoplasma gondii and Eimeria tenella and novel anticoccidial drugs have been requested. In this study, the anticoccidial effect of 3-(4-methoxybenzylaminomethylene)-1,3-dihydroindole-2-one (5-108) on T. gondii and E. tenella was evaluated. Novel synthetic derivative 5-108 showed 1.44 fold higher relative selectivity compared to pyrimethamine against T. gondii in vitro assay. In chicken study, compound 5-108 significantly decreased the number of oocytes of E. tenella in feces, obtained from E. tenella-infected chickens, by $33{\pm}2.64%$ and $23{\pm}3.60%$ (P<0.001) at $7^{th}$ day and $9^{th}$ day p.i.. Conclusively, compound 5-108 was effective against T. gondii and E. tenella.

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.31-38
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• 2016

Specific gene expressions of host cells by spontaneous STAT6 phosphorylation are major strategy for the survival of intracellular Toxoplasma gondii against parasiticidal events through STAT1 phosphorylation by infection provoked $IFN-{\gamma}$. We determined the effects of small molecules of tyrosine kinase inhibitors (TKIs) on the growth of T. gondii and on the relationship with STAT1 and STAT6 phosphorylation in ARPE-19 cells. We counted the number of T. gondii RH tachyzoites per parasitophorous vacuolar membrane (PVM) after treatment with TKIs at 12-hr intervals for 72 hr. The change of STAT6 phosphorylation was assessed via western blot and immunofluorescence assay. Among the tested TKIs, Afatinib (pan ErbB/EGFR inhibitor, $5{\mu}M$) inhibited 98.0% of the growth of T. gondii, which was comparable to pyrimethamine ($5{\mu}M$) at 96.9% and followed by Erlotinib (ErbB1/EGFR inhibitor, $20{\mu}M$) at 33.8% and Sunitinib (PDGFR or c-Kit inhibitor, $10{\mu}M$) at 21.3%. In the early stage of the infection (2, 4, and 8 hr after T. gondii challenge), Afatinib inhibited the phosphorylation of STAT6 in western blot and immunofluorescence assay. Both JAK1 and JAK3, the upper hierarchical kinases of cytokine signaling, were strongly phosphorylated at 2 hr and then disappeared entirely after 4 hr. Some TKIs, especially the EGFR inhibitors, might play an important role in the inhibition of intracellular replication of T. gondii through the inhibition of the direct phosphorylation of STAT6 by T. gondii.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.379-384
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• 2012

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.

• Parasites, Hosts and Diseases
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• v.47 no.2
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• pp.139-144
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• 2009

The aim of the present study was to investigate antimalarial drug pressure resulting from the clinical use of different antimalarials in Thailand. The phenotypic diversity of the susceptibility profiles of antimalarials, i.e., chloroquine (CQ), quinine (QN), mefloquine (MQ), and artesunate (ARS) in Plasmodium falciparum isolates collected during the period from 1988 to 2003 were studied. P. falciparum isolates from infected patients were collected from the Thai-Cambodian border area at different time periods (1988-1989, 1991-1992, and 2003), during which 3 different patterns of drug use had been implemented: MQ+sulphadoxine (S)+pyrimethamine (P), MQ alone and MQ+ARS, respectively. The in vitro drug susceptibilities were investigated using a method based on the incorporation of $[^3H]$ hypoxanthine. A total of 50 isolates were tested for susceptibilities to CQ, QN, MQ, and ARS. Of these isolates, 19, 16, and 15 were adapted during the periods 1988-1989, 1991-1993, and 2003, respectively. P. falciparum isolates collected during the 3 periods were resistant to CQ. Sensitivities to MQ declined from 1988 to 2003. In contrast, the parasite was sensitive to QN, and similar sensitivity profile patterns were observed during the 3 time periods. There was a significantly positive but weak correlation between the $IC_{50}$ values of CQ and QN, as well as between the $IC_{50}$, values of QN and MQ. Drug pressure has impact on sensitivity of P. falciparum to MQ. A combination therapy of MQ and ARS is being applied to reduce the parasite resistance, and also increasing the efficacy of the drug.