Light and electron microscopic studies of the structural damages of acanthamoeba cysts by pouzolzia indica methanolic extract fraction 4 solution.

Objective : This study was to investigate the morphological changes and ultrastructural damages of the Acanthamoeba cysts after treated with the minimal cysticydal concentration (MCC) of Pouzolzia indica methanolic extract fraction 4 solution by light and electron microscopies. Materials and Methods : Acanthamoeba cyst which prepared followed the method of Roongruangchai K15,16 were adjusted to the final concentration of 104 cysts/ml and treated with 1:4 soltion of fraction 4 Pouzolzia indica methanolic extract, the Thai medicinal plant. which was the minimal cysticidal concentration (MCC) 16. The cysts then, were centrifuged and the pellets were prepared for light, scanning and transmission electron microscopies. Result : Light micrographs showed the cytoplasmic clumping and some empty cyst wall. Transmission electron microscopy showed the ruptures of both ectocyst and the endocyst wall with some opercula damages. The cytoplasm aggregated and clumped. Scanning electron microscopy show steps of damage which started from shrinkage and collapsed of the cyst walls, then the cysts began to bulge and swell resulted in decreasing in the wrinkles of the cyst walls. The cytoplasmic contents drain out from the cyst wall and finally the cyst walls were ripped and torn into small pieces. Conclusion : Pouzolzia indica methanolic extract fraction 4 at the MCC of 1:4 caused structural damages to the Acanthamoeba cyst including shrinking of the cyst walls with the ruptured of the ectocyst, endocyst and operculum, edema and break out into pieces. The active ingredients of this Thai medicinal plant should be further studied as this can eventually be one of the regimen for the treatment of the Acanthamoeba keratitis or as a solution for cleaning the contact lens or contact lens case solution.

Mutational analyses of K-ras exon 2 in Thailand colorectal cancer tissue samples.

Objective: The main purpose of this study was to elucidate the genotype of K-ras gene in Thailand colorectal cancer tissue samples, especially in exon 2, which has never before been reported. Methods: 106 patients’ samples in formalin fixed paraffin embedded tissue blocks were investigated in this study. DNA was extracted and PCR was performed by using primers specific for the K-ras gene at exon 2. Direct sequencing was performed in a Genetic Analyser ABI3130 with specific software. Results: The mutation of K-ras exon 2 gene in Thailand colorectal cancer samples accounted for 37.7% of the total. The most common mutation found in this series was the G"A transition which accounted for 70%. Conclusion: The incidence of K-ras exon 2 mutation in Thailand colorectal cancer samples was remarkedly similar to previous reports.

Antiproliferative and antimicrobial activities of endophytic fungus isolated from erycibe elliptilimba.

Background: Erycibe elliptilimba Merr.&Chun. is a Thai herb in the family Convolvulaceae that has long been used in traditional medicine to treat various diseases including infections and malignancies. Its methanolic extract has antiproliferative activities against various human cancer cell lines with potential ED50 values. Objective: The antiproliferative activities exhibited from this plant should be investigated to ensure that the effects were from the plant itself. Therefore, the endophytic fungus from this special plant was isolated and evaluated for their antiproliferative and antimicrobial activities. Methods: The isolation of fungal endophytes from the stems of Erycibe elliptilimba Merr.&Chun. was identified by macroscopic and microscopic morphology. Fungal extraction was demonstrated using thin layer chromatography of the crude broth extract. Four human breast cancer cell lines, two human lung cancer cell lines, and one human colon cancer cell line were used to evaluate the antiproliferative activity of the crude broth extract on the cell growth and determine of antibacterial activities. Results: The results revealed that only one species, Trichoderma ovalisporum, was isolated and its cultured broth extract did not provide an antiproliferative effect against any human cancer cell line nor antimicrobial activities. Conclusion: Based on this study, the antiproliferative activities against several human cancer cell lines of Erycibe elliptilimba, Merr&Chun extract, in recent reports may depend upon the active compounds in the plant itself.

Several fractions of pouzolzia indica methanolic extract were lethal to the acanthamoeba cyst: in vitro study.

Objective: The purpose of this study was to compare the least concentrations of 5 fractions of Pouzolzia indica methanolic extract which can be lethal to the cyst form of the Acanthamoeba spp. Methods: Acanthamoeba spp. was isolated from a keratitis patient and was cultured using nonnutrient agar plates enriched with heat-killed E.coli for seven days at room temperature for the production of mature cysts. The cysts were harvested, washed in normal saline solution and adjusted to the final concentration of 104 cysts/ml. They were mixed with several dilutions of each fraction of Pouzolzia indica methanolic extract. After incubation for 1 hour, they were washed and centrifuged to remove the herbal extract supernatants. The cysts were recultured in the same medium for 7 days to confirm that they were all dead. Results: Pouzolzia indica methanolic extract fraction No. 1 which was eluted by water could not kill the cyst, while the crude extract (Fraction C) could at the concentration of 1:2. The fraction No.2 which was eluted by water: methanol had the minimal cysticidal concentration of 1:4, fraction No.3 which was eluted by methanol had the minimal cysticidal concentration of 1:8 and the fraction No.4 which was eluted by ethyl acetone had the minimal cysticidal concentration of 1:4. Concluison: Our results demonstrated that the Pouzolzia indica methanolic extract of several fractions can be cysticidal to an Acanthamoeba cyst, and this can modified to be a better disinfecting solution for contact lens cases.

Antiproliferative effect of cucurbitacin B extracted from trichosanthes cucumerina L. on human cancer cell lines.

Objective: To determine the antiproliferative effect of cucurbitacin B extracted from Trichosanthes cucumerina L. on human cancer cell lines. Methods: Two human lung non-small cell (adenocarcinoma) cancer cell lines i.e., LK87, and QG95, two human colon adenocarcinoma cell lines i.e., HCT15, and HT29, including one renal cancer cell line, A498, and one pancreatic cancer cell line, NOR-P, were used in this study. The viability of cells was assessed by using WST-8 which is based on detection of LDH released from damaged cells and reacts with WST-8 to form a yellow color. Cells were treated with the compound at various concentration from 1 through 100 µg/ml. Results: The ED50 values (effective doses that are required for 50% inhibition growth of tumor cells) of the compound on human cancer cell lines ranged from approximately 69 µg/ml in HCT15 cells up to 231 µg/ml in QG95 cells. The inhibition of proliferation of this compound on these human cancer cell lines was observed to be in a dose dependent manner. Conclusion: It could be concluded from this observation that this compound has a modest direct toxic effect to these cell lines with the highest toxic effect on human colon cancer cells.

Prevalence of 60 kda and 52 kda Ro/SS-A autoantibodies in anti-Ro positive Thai sera in Siriraj Hospital.

BACKGROUND: Anti-Ro antibody may directly react against either Ro60 or Ro52 or both antigens. To be more applicable for routine laboratory practice, the specific antigen type for antibody detection should be identified before test application. OBJECTIVE: Investigate the prevalence of 60 kDa and 52 kDa Ro/SS-A antibodies in Thai patients' sera in Siriraj Hospital. MATERIAL AND METHOD: Specimens for anti-Ro were requested between June and December 2005. They were tested with EUROLINE test kit for prevalence determination. The principle of the test is a qualitative in-vitro-assay that contains test strips coated with parallel lines of 14 highly purified antigens. Of 84 specimens requested for anti-Ro antibody, 76 were collected and tested with the EUROLINE test kits and eight were excluded due to inadequacy. RESULTS: The prevalence of anti-Ro60 and anti-Ro52 of all sera tested for anti-Ro by EUROLINE test kit were 30% (95% CI: 20-40%) and 26% (95% CI: 16-36%), respectively; and, those in anti-Ro positive Thai sera were 82% (95% CI: 68-96%) and 71% (95% CI: 54-88%), respectively. The prevalence of anti-Ro52 alone in anti-Ro positive Thai sera and all specimens requested for anti-Ro was about 18% (95% CI: 4-32%) and 7% (95% CI: 1-13%), respectively. The agreement and Kappa value between the two methods were 0.9 and 0.77, respectively. The study suggests that the test for anti-Ro detection should provide both Ro 60 and Ro 52 antigens. CONCLUSION: The prevalence of both anti-Ro 60 and anti-Ro 52 were quite common, therefore, the test for this specific antibody should provide both antigens for antibody detection.

Antibacterial activities of four Thai medicinal plants.

Medicinal plants have long been used and prescribed in Thailand for centuries. Some of them have been used for treating various diseases including infectious diseases. Pouzolzia pentandra Benn., Gelonium multiflorum A. Juss., Erycibe elliptilimba Merr. and Chun., Balanophora abbreviate Bl. are Thai medicinal plants from the Thai pharmacopoeia that have been prescribed for treating unknown fevers including some specific infectious diseases. This investigation demonstrated the effects of these Thai medicinal plants for their antibacterial activities by using the macrodilution assay. Based on the present study, the water methanol fraction (fraction 2) of Balanophora abbreviate Bl. showed the antibacterial activity at the MIC level of 250 microg/ml but the activity was bacteriostatic in its effects. Therefore, the use of these medicinal plants in controlling fever and infectious diseases appears to be justified and further investigations may be required to obtain more information.

Molecular mechanism of herbs in human lung cancer cells.

Herbs have been considered natural and valuable sources for anticancer drug discovery. Herbal medicine has been prescribed in many countries over centuries for treating various diseases including infectious and malignant diseases. Nowadays, many of the drugs that have been used for treatment of malignant diseases are derived from natural products such as Taxol, a natural product isolated initially from Pacific Yew (Taxus brevifolia). This review article describes research on molecular mechanisms, especially cytotoxic effect of natural products from plant sources, primarily preclinical studies, involving human lung cancer cells in vitro for providing more knowledge and issues for potential drug development from medicinal herbs in the future.

Antiprolifrative activities of three Thai medicinal plants on human cancer cells.

In Thailand, the stems and leaves of Pouzolzia pentandra Benn., stems of Erycibe elliptilimba Merr.& Chun., and Gelonium multiflorum A. Juss. have long been used as traditional medicines for cancer therapy. The ethanol, water, methanol:water and ethyl acetate extracts of these three plants were tested in vitro against four different human breast cancer cell lines and two human lung cancer cell lines using MTT screening method. The methanol extract of Erycibe elliptilimba Merr. & Chun. showed the most potent antiproliferative activities against these specific human cancer cells. The results, therefore, suggested to some extent the benefit of the traditional use of Erycibe elliptilimba Merr.& Chun. in the treatment of malignancies.