Suchart Kothan

Quercetin, Siamois 1 and siamois 2 induce apoptosis in human breast cancer MDA-MB-435 cells xenograft in vivo

We sought to investigate the apoptosis-inducing activities of quercetin, Siamois 1, and Siamois 2 against invasive estrogen-receptor negative MDA-MB 435 cells xenografted in athymic nude mice. This study clearly demonstrated that these compounds exhibited apoptosis-inducing activities in cell culture system. Quercetin (20 μg/mL), Siamois 1 (100 μg/mL), and Siamois 2 (200 μg/mL) can induce apoptotic cell death by 40± 5%, 44 ± 14 %, and 31 ± 13 %, respectively. Two-fold of IC50 of these compounds were clearly found to induce apoptosis in breast tumor tissue which can be determined by 99mTc-annexin V scintigraphy and histological staining. This is the first report that the apoptosis-inducing effects of quercetin, Siamois 1, and Siamois 2 on the MDA-MB 435 cell in vitro were effectively extrapolated to the in vivo situation. These compounds might be considered as a simple dietary supplement and with further clinical investigation for their use as a nutrition-based intervention in breast cancer treatment.

Chitosan-triphosphate nanoparticles for encapsulation of super-paramagnetic iron oxide as an MRI contrast agent

Super-paramagnetic iron oxide nanoparticles (SPIONPs) were encapsulated at various concentrations within chitosan-triphosphate (SPIONPs-CS) nanoparticles using an ionotropic gelation method. The encapsulation of SPIONPs within CS nanoparticles enhanced their dispersion ability in aqueous solution, with all particles being lower than 130 nm in size and having highly positive surface charge. The SPIONPs-CS nanoparticles exhibited crystalline structure and super-paramagnetic behavior, as seen in non-encapsulated SPIONPs. The morphology of SPIONPs-CS nanoparticles showed that they almost spherical in shape. The effect of phantom environments (culture medium and 3% agar solution) on either T1 or T2 weighted MRI was investigated using a clinical 1.5T MRI scanner. The results revealed that 3% agar solution showed relaxation values higher than the culture medium, leading to a significant decrease in the MR image intensity. Our results demonstrated that the SPIONPs-CS nanoparticles can be applied as tissue-specific MRI contrast agents.

Luminescence characteristics of Dy3+ doped Gd2O3-CaO-SiO2-B2O3 scintillating glasses

Abstract Glasses were prepared from the compositions of 25Gd 2 O 3 -10CaO-10SiO 2 -(55– x )B 2 O 3 - x Dy 2 O 3 (where x is 0.0 mol.%–1.0 mol.%) by the conventional melt-quenching technique at 1400 °C. The results demonstrated the increase in the glass density with respect to the increase in the doping concentrations of Dy 2 O 3 . Nine absorption bands were observed. The emission spectra of the developed glass showed two strong peaks at 577 nm ( 4 F 9/2 → 6 H 13/2 ) and 482 nm ( 4 F 9/2 → 6 H 15/2 ). The highest emission intensity was observed from the developed glass prepared at 0.4 mol.% of Dy 2 O 3 , as the efficient energy transfer took place from Gd 3+ to Dy 3+ . From the X-ray induced optical luminescence, the emission spectra were identical to those from PL measurements, but with the highest intensity observed from the glass quenched at 0.45 mol.% of Dy 2 O 3 . Finally, the integral scintillation efficiency of the developed glass was determined at 27% of that of the commercially available BGO crystal.

Spectrophotometric Characterization of Behavior and the Predominant Species of Flavonoids in Physiological Buffer: Determination of Solubility, Lipophilicity and Anticancer Efficacy

The objectives of this study were to investigate the behavior of flavonoids in an aqueous physiological buffer and to determine the structural and functional group substitution which is responsible for their anticancer action. The de- protonated anionic form of 7 flavonoids can easily be determined using spectrophotometry, and owing to its charged state, is highly soluble in aqueous physiological buffer and is not prone to aggregation. The protonated form of these 7 flavon- oids is much less soluble and tends to aggregate following precipitation. For all flavonoids studied except catechin and 5,5� -dihydroxy-6,7,3� ,4� -tetramethoxyflavone, it was possible to determine the rates of deprotonation; pKa value of eri- odictyol, apigenin, kaempferol, quercetin, WP 279, and WP 283 was equal to 7.00, 8.72, 7.86, 8.30, 7.70 and 9.90, respec- tively. The methoxyl group substitutions in place of hydrogen atoms and/or hydroxyl groups at various positions of car- bon atoms in ring A, B and C particularly WP 283 resulted in an increase in the solubility, lipophilicity, and specifically its anticancer efficacy (by 60-fold). The neutral forms of flavonoids are predominantly active molecules and the active sites responsible for anticancer activity are found in ring A and C, especially C4=O, C5-OH and C2=C3.

MRI and 1H MRS evaluation for the serial bile duct changes in hamsters after infection with Opisthorchis viverrini

A 3T MR scanner was used to investigate the relationship between the alteration of bile duct lesions and the hepatic metabolic changes in hamsters infected with Opisthorchis viverrini by using 3T MRI and (1)H MR spectroscopy. Animals were divided into control and infected groups. Five normal hamsters were used as control; fifty-five hamsters were infected with O. viverrini to induce bile duct lesions and hepatic metabolic changes. T2-weighted image sequence in three orthogonal planes were conducted by MRI scans. Single-voxel (1)H MRS was performed to obtain the relative choline-to-lipid ratios. The livers and bile ducts were excised for the histologic examination. The progression of bile duct changes by histology and metabolic changes in O. viverrini infected hamsters were co-investigated. In the O. viverrini-infected group, the T2-weighted images revealed the time-dependent intra- and extra-hepatic duct dilatations in the liver. The mean (±SD) choline-to-lipid ratios were 0.11±0.035 in the control group, whereas the ratio in the infected group increased significantly with the progression of time. Histologic grading of hepatic inflammation and fibrosis were correlated well with the MRI grading (Spearman rank correlation test; r=0.746 and p<0.001). The control group showed no dilatation of the bile ducts and showed normal liver patterns. Noninvasive technique, MRI and (1)H MRS can demonstrated and applied to evaluate not only the inflammation-related fibrosis in the small bile ducts but also the metabolic changes in the liver induced by O. viverrini infection. A significant increase in the choline-to-lipids ratios were observed in parallel with the time-course of infection. O. viverrini infected in human is detected by stool examination. Hepatobiliary morbidity is detected and followed up by ultrasonography. MRI and MRS can be used in conjunction with ultrasonography for evaluation of progression of the disease.

Super-paramagnetic loaded nanoparticles based on biological macromolecules for in vivo targeted MR imaging.

Target-specific MRI contrast agent based on super-paramagnetic iron oxide-chitosan-folic acid (SPIONP-CS-FA) nanoparticles was fabricated by using an ionotropic gelation method, which involved the loading of SPIONPs at various concentrations into CS-FA nanoparticles by electrostatic interaction. The SPIONP-CS-FA nanoparticles were characterized by ATR-FTIR, XRD, TEM, and VSM techniques. This study revealed that the advantages of this system would be green fabrication, low cytotoxicity at iron concentrations ranging from 0.52 mg/L to 4.16 mg/L, and high water stability (pH 6) at 4°C over long periods. Average particle size and positive zeta-potential of the SPIONP-CS-FA nanoparticles was found to be 130 nm with narrow size distribution and 42 mV, respectively. In comparison to SPIONP-0.5-CS nanoparticles, SPIONP-0.5-CS-FA nanoparticles showed higher and specific cellular uptake levels into human cervical adenocarcinoma cells due to the presence of folate receptors, while in vivo results (Wistar rat) indicated that only liver tissue showed significant decreases in MR image intensity on T2 weighted images and T2* weighted images after post-injection, in comparison with other organs. Our results demonstrated that SPIONP-CS-FA nanoparticles can be applied as an either tumor or organ specific MRI contrast agents.

Antioxidant compounds and activities of the stem, flower, and leaf extracts of the anti-smoking Thai medicinal plant: Vernonia cinerea Less

Vernonia cinerea (VC) Less has been proposed as a medicinal plant with interesting activities, such as an aid for smoking cessation worldwide. Despite its previous clinical success in smoking cessation by exhibiting reduced oxidative stress, it has not been approved. The aim of this study was to investigate various antioxidant activity and active compounds that have not been approved, including the protective activity in human red blood cells (RBCs), from the stem, flower, and leaf extracts of VC Less in vitro. These extracts were tested for their antioxidant activity in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and analyzed by high-performance liquid chromatography (HPLC) for their active compounds: total tannin, five catechin (C) compounds (epicatechin gallate [ECG], C, epicatechin [EC], epigallocatechin gallate [EGCG], and (−)-epigallocatechin [EGC]), flavonoid, nitrite, nitrate, caffeine, and nicotine. Moreover, antioxidant activities of the extracts were evaluated in 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH)-treated RBCs. The results showed that the flower and leaf of VC Less had higher activity than the stem in scavenging DPPH radicals. The tannin content in the flower and leaf was higher than that in the stem. The leaf had the highest content of the five catechins (C, EC, EGCG, ECG, and EGC), the same as in the flavonoid, when compared to the stem and flower. Furthermore, the leaf extract had higher nitrate and nitrite than the stem. Nicotine content was found to be higher in the leaf when compared to the flower. In addition, the leaf showed protective activity in glutathione (GSH), malondialdehyde (MDA), and protein carbonyl, with a dose response in AAPH-oxidized RBCs, the same as in standard EGCG. Thus, this study concluded that radical scavenging and antioxidant compounds such as catechins, flavonoid, nitrate and nitrite, and nicotine are present in different VC Less parts and are included in the AAPH-oxidized RBC model.

Bone mineral density at distal forearm in men over 40 years of age in Mae Chaem district, Chiang Mai Province, Thailand: a pilot study

Abstract Objective: To study the prevalence of bone mineral density (BMD) and osteoporosis in the distal forearm among Thai men over 40 years of age in Mae Chaem District, Chiang Mai Province, Thailand. Methods: The subjects in this study were 194 Thai men, aged between 40 and 87 years who resided in Mae Chaem District, Chiang Mai Province, Thailand. Self-administered questionnaires were used for receiving the demographic characteristics information. BMD was measured by peripheral dual energy X-ray absorptiometry at the nondominant distal forearm in all men. Results: The BMD was highest in the age-group 40–49 years and lowest in the age-group 70–87 years. The average T-score at the distal forearm was also highest in the age-group 40–49 years and lowest in the age-group 70–87 years. The BMD decreased as a function of age-group (p < .05). In contrast, the BMD increased as a function of weight (p < .05). Height had weak impact on the BMD in the distal forearm (p > .05). The percentage of osteopenia and osteoporosis are increased as a function of age-group in, while decreased in that of normal bone density. Conclusions: We found the prevalence of osteoporosis in men who resided in Mae Chaem District, Chiang Mai Province, Thailand.

Short-Term Effects of Cognitive Training Program for Individuals with Amnestic Mild Cognitive Impairment: A Pilot Study

ABSTRACT This study examined the effects of a cognitive training program on cognitive function and neurochemistry changes in individuals with amnestic mild cognitive impairment (aMCI). Ten individuals with aMCI were randomly assigned to the experimental (n = 5) and control (n = 5) groups. The experimental group took part in an 18-session cognitive training program over a 6-week period. After completing the cognitive training course, the experimental group demonstrated significant improvement in memory, attention, and executive functions. With respect to the neurochemistry biomarkers, the myoinositol/creatine (mI/Cr) ratio was significantly decreased in the hippocampus, prefrontal cortex, and anterior cingulate cortex of the experimental group after training. Findings demonstrate that the cognitive training program showed promising evidence in improving cognitive functions in individuals with aMCI. The observed cognitive function improvement was accompanied by a decrease of mI levels.

An evaluation of the antioxidant properties of iodinated radiographic contrast media: An in vitro study

Graphical abstract