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We developed a robust analytical method for quantification of malondialdehyde (MDA) in urine and serum samples using dansylhydrazine (DH) as a derivatizing reagent. The derivatization procedure was partially carried out using an autosampler injection program to minimize errors associated with the low-volume addition of reagents and was optimized to yield a stable hydrazone derivative of MDA and its labeled d2-MDA analogue. The target MDA-DH derivatives were separated on an Agilent Zorbax Eclipse Plus Phenyl-Hexyl (3.0 × 100 mm, 3.5 μm) column. The mass-to-charge ratios of the target derivatives [(M+H)+ of 302 and 304 for MDA-DH and d2-MDA-DH, respectively] were analyzed in single ion monitoring mode using a single quadrupole mass spectrometer operated under positive electrospray ionization. The method limits of quantification were 5.63 nM (or 0.405 ng/mL) for urine analysis and 5.68 nM (or 0.409 ng/mL) for serum analysis. The quantification range for urine analysis was 5.63–500 nM (0.405–36.0 ng/mL) while the quantification range for serum analysis was 5.68–341 nM (0.409–24.6 ng/mL). The method showed good relative recoveries (98–103%), good accuracies (92–98%), and acceptable precisions (relative standard deviations 1.8–7.3% for inter-day precision; 1.8–6.1% for intra-day precision) as observed from the repeat analysis of quality control samples prepared at different concentrations. The method was used to measure MDA in individual urine samples (n = 287) and de-identified archived serum samples (n = 22) to assess the overall performance of the method. The results demonstrated that our method is capable of measuring urinary and serum levels of MDA, allowing its future application in epidemiologic investigations.

Radon is a major cause of lung cancer (LC) deaths among non-smokers worldwide. However, no serum biomarker for screening of LC risk in high residential radon (HRR) areas is available. Therefore, the aim of this study was to determine diagnostic values of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (Cyfra21-1), human epididymis protein 4 (HE4), interleukin 8 (IL-8), migration inhibitory factor (MIF), tumor nuclear factor-alpha (TNF-α) and vascular endothelial growth factors (VEGF) occurring in high radon areas. Seventy-five LC non-smoker patients and seventy-five healthy controls (HC) were enrolled in this study. Among the HC groups, twenty-five HC were low residential radon (LRR) and fifty HC were HRR. Significantly higher (p < 0.0004) serum levels of CEA, Cyfra21-1, IL-8 and VEGF were found in the LC compared with the LRR and HRR groups. More importantly, significantly higher levels (p < 0.009) of serum CEA, Cyfra21-1 and IL-8 were observed in HRR compared with the LRR group. Likewise, a ROC curve demonstrated that serum CEA and Cyfra21-1 could better distinguish LC risk from HRR groups than IL-8. These results indicated that serum CEA and Cyfra21-1 were significantly increased in the HRR group and may be considered as potential biomarkers for individuals at high-risk to develop LC.

Moringa oleifera Lam. (M. oleifera) has been called the “miracle tree” due to its attributes for therapy in various diseases. However, M. oleifera studies on the male reproductive system have been limited. The aim of this study was a phytochemical screening and investigation of the effects of M. oleifera leaf tea on sexual behavior, reproductive function and antioxidant activities. Male rats were fed with M. oleifera leaf tea extract at doses of 0.55, 1.10 and 2.20 mg/kg or distilled water for 30 days. The result showed that M. oleifera leaf tea contained rich total phenols and flavonoids. The courtship behavior, seminiferous tubule diameter, epithelium height, epithelium area, type A spermatogonia, and spermatogonia efficiency were significantly increased in all treatment groups. The groups treated with 1.10 and 2.20 mg/kg increased the number of Sertoli cells. The total of spermatogenic cells increased in the group treated with 0.55 mg/kg. M. oleifera leaf tea scavenged DPPH radical, ABTS radical and H2O2, and inhibited LPO and AGEs formation. Due to M. oleifera leaf tea containing rich total phenols, flavonoids, and antioxidants, it could enhance sexual function and the male reproductive system.

Sacred lotus (Nelumbo nucifera Gaertn., N. nucifera) is a common ingredient in traditional medicine and Thai recipes. Its petal is an agricultural waste from stamen production. There are limitations in the used and pharmacological data of the petals resulting in more petals waste. The aims of this study were to investigate the phytochemical contents, antioxidant activity, and potential effects on sperm viability of aqueous (NAE) and ethanolic extracts (NEE) of both red and white N. nucifera petals. The white NAE had the highest total phenolics content, total tannins content and maximal antioxidant activity. The white NEE had the highest concentration of total flavonoids. Quercetin was a major flavonoid and was found in the aqueous extracts. Both red and white of NAE in the range of 0.22 to 1.76 mg/mL increased sperm viability. The white NAE was prominent in phytochemical content, antioxidant activity, and both red and white NAE effectively increased rat sperm viability in the in vitro model. The white NAE enhanced sperm viability by decreasing oxidative stress. It might be suggested that the N. nucifera petals have benefits for sperm viability health promotion and may increase the economic value of agricultural waste.

Radiation-induced bystander effect (RIBE) has been identified as an important contributing factor to tumor resistance and normal tissue damage. However, the RIBE in cancer and normal cells under hypoxia remain unclear. In this study, confluent A549 cancer and WI-38 normal cells were subjected to condition of hypoxia or normoxia, before exposure to high-LET protons microbeam. After 6 h incubation, cells were harvested and assayed for colony formation, micronucleus formation, chromosome aberration and western blotting. Our results show that there were differences of RIBE in bystander A549 and WI-38 cells under hypoxia and normoxia. The differences were also observed in the roles of HIF-1α expression in bystander A549 and WI-38 cells under both conditions. Furthermore, inhibition of gap junction intercellular communication (GJIC) showed a decrease in toxicity of hypoxia-treated bystander A549 cells, but increased in bystander WI-38 cells. These findings clearly support that GJIC protection of bystander normal cells from toxicity while enhancing in bystander cancer cells. Together, the data show a promising strategy for high-LET radiation in designing an entire new line of drugs, either increase or restore GJIC in bystander cancer cells which in turn leads to enhancement of radiation accuracy for treatment of hypoxic tumors.

Tryptophan (TRP) is an essential amino acid and is metabolized via kynurenine and serotonin pathway. Both pathways are significant role in many diseases and have been studied as biomarkers for differentiate and clarify in many diseases including forensic works. Metabolism in the body might be affected by both intrinsic and extrinsic factors. This study aimed to compare postmortem blood level of TRP and its metabolites in male and female to be applied in gender identification in forensic medicine cases. Blood samples were collected from male group (n=11) and female group (n=11) and the level of the TRP and its metabolites were identified by HPLC-DAD. The values of the TRP, metabolites and metabolite ratios did not different between the groups. While, the value of ratio of picolinic acid/ quinolinic acid different significantly (p

Background: Chronological age estimation is an important process for corpse identification. Advancedglycation end products (AGEs) are accumulated during lifetime and have been used for forensic identification.The AGEs in vitreous humor still lack of information for age estimation. Objective: To investigate correlationbetween the AGEs level contained in vitreous humor and chronological age in postmortem cases. Methods:The vitreous humor samples were collected from the postmortem cases (n=142). The AGEs levels weredetermined by spectrofluorometer and presented in microgram of quinidine hemisulfate equivalent (?g QE/mL) and nanogram of pentosidine equivalent (ng PE/mL). Stepwise linear regression was used to generatethe equation. Results: The QE and PE showed mild positive correlation (r = 0.350 and 0.195; p

Tetraponera rufonigra (Arboreal Bicoloured Ant) venom induces pain, inflammation, and anaphylaxis in people and has an increased incident in Southeast Asia regions. The bioactive components and mechanism of action of the ant venom are still limited. The aim of this research was to identify the protein composition and inflammatory process of the ant venom by using RAW 264.7 macrophage cells. The major venom proteins are composed of 5’ nucleotidase, prolyl endopeptidase-like, aminopeptidase N, trypsin-3, venom protein, and phospholipase A2 (PLA2). The venom showed PLA2 activity and represented 0.46 μg of PLA2 bee venom equivalent/μg crude venom protein. The venom induced cytotoxic in a dose- and time-dependent manner with IC20 approximately at 4.01 µg/mL. The increased levels of COX-2 and PGE2 were observed after 1 h of treatment correlating with an upregulation of COX-2 expression. Moreover, the level of mPGES-1 expression was obviously increased after 12 h of venom induction. Hence, our results suggested that the induction of COX-2/mPGEs-1 pathway could be a direct pathway for the ant venom-induced inflammation.

Age estimation is an important step in post-mortem investigation, and the aspartic acid racemization (AAR) of dentin is the best tool for age estimation from human remains. However, teeth may not be found or sufficiently preserved to analyse the Dextro/Levo (D/L) ratio, and so age estimation using AAR from other organs, such as bones, is required. The current study evaluated age estimation methods using aspartic amino acid racemization from a femur in a Thai population. D/L ratio analysis using high-performance liquid chromatography (HPLC) was performed on 40 femoral bones from 24 males and 16 females, and the correlation between D/L ratio and age was 0.8316. The correlation coefficient in the male sample was greater than the female samples – 0.912 and 0.716, respectively. The standard error of estimation of all samples was 11.01 years. The correlation between the D/L ratio and the age of the total amino acid fraction from a femur was not as strong as from dentin and single protein purification, s...

Objectives: Caffeic acid (CAF) and its amide analogues, ethyl 1-(3’,4’-dihydroxyphenyl) propen amide (EDPA), phenethyl 1-(3’,4’-dihydroxyphenyl) propen amide (PEDPA), phenmethyl 1- (3’,4’-dihydroxyphenyl) propen amide (PMDPA) and octyl 1-(3’,4’-dihydroxyphenyl) propen amide (ODPA) were investigated for the inhibition of procarcinogen activating enzyme. Methods: CYP1A2 and scavenging activity on formation of nitric oxide, superoxide anion, DPPH radical and hydroxyl radical. Results: It was found that they inhibited CYP1A2 enzyme by uncompetitive inhibition. Apparent Ki values of CAF, EDPA, PEDPA, PMDPA and ODPA were 0.59, 0.39, 0.45, 0.75 and 0.80 µM, respectively suggesting potent inhibitors of CYP1A2. Moreover, they potentially scavenged nitric oxide radical with IC 50 values of 0.12, 0.22, 0.28, 0.22 and 0.51 mM, respectively. The IC50 values of superoxide anion scavenging were 0.20, 0.22, 0.44, 2.18 and 2.50 mM, respectively. 1, 1- diphenyl-2- picrylhydrazyl (DPPH) radical-scavenging ability, shown as IC50 values, were 0.41, 0.29, 0.30, 0.89 and 0.84 mM, respectively. Moreover, the hydroxyl radical scavenging in vitro model was shown as IC50 values of 23.22, 21.06, 17.10, 17.21 and 15.81 µM, respectively. Conclusion: From our results, caffeic acid and its amide analogues are in vitro inhibitors of human CYP1A2 catalytic activity and free radical formation. They may be useful to be developed as potential chemopreventive agents that block CYP1A2-mediated chemical carcinogenesis.

Coronary heart disease (CHD) is the major cause of death in sudden unexpected death (SUD) cases. Tryptophan (TRP) and its metabolites are correlated with the CHD patient but less studies in the SUD. The aim of this study was to evaluate the relationship of TRP and its metabolites with the CHD in the SUD cases. Blood samples and heart tissues were collected from CHD subjects (n = 31) and the control group (n = 72). Levels of kynurenine (KYN), kynurenic acid (KYA), xanthurenic acid (XAN), 3-hydroxyanthranillic acid (HAA), quinolinic acid (QA), picolinic acid (PA) and 5-hydroxyindoleacetic acid (HIAA) were determined by HPLC-DAD. A severity of heart occlusion was categorized into four groups, and the relationship was measured with the TRP metabolites. The HIAA and The KYN levels significantly differed (p &lt, 0.01) between the CHD group and the control group. Lower levels of QA/XAN, PA/KA, HAA/XAN, KYN/XAN and KYN/TRP were found in the CHD group. However, PA/HAA, PA/HIAA, PA/KYN and XAN/KA values in the CHD group were higher than the control group (p &lt, 0.05). This study revealed that the values of PA/KA and PA/HAA provided better choices for a CHD biomarker in postmortem bodies.

Background: Derris scandens (DS) has been used in Thai traditional medicine recipes for musculoskeletal pain relief in Southern Thailand. Changing of terrain and climate affected its phytochemical constituents and led to change antioxidant and toxic properties. Objective: The aim of this study was to study phytochemical contents, antioxidant properties, and toxicity of the DS extracts' in vitro models. Materials and Methods: The DS ethanolic extract (EE) was partially extracted with chloroform (CE), ethyl acetate (EAE), and water (aqueous extract [AE]). Phytochemical contents, antioxidant properties, and toxicity in Caco-2 cells, peripheral blood mononuclear cells (PBMCs), and red blood cells (RBCs) were explored. Results: Genistein and gallic acid were rich in the EE and CE. The CE demonstrated the highest 2,2 − diphenyl − 1 − picrylhydrazyl scavenging activity with half-maximal Radical cavenging concentration (SC50) value – 0.81 ± 0.07 mg/mL. The EE showed the highest 2, 2'−azino − bis (3 − ethylbenzothiazoline − 6 − sulfonic acid) radical scavenging activity (SC50 = 22.05 ± 3.91 μg/mL) and all the extracts strongly inhibited lipid peroxidation. The EE and CE were more toxic than the EAE on Caco-2 cells with IC50 values – 26.45 ± 3.57 and 36.36 ± 6.87 μg/mL, respectively. At high dose, all fractions were not toxic to human's PBMCs, but they slightly induced RBC hemolysis by 3-6 percent. Conclusions: The DS grown in Southern Thailand had antioxidant properties, toxic to Caco-2 cells and not toxic to normal cells. High dose and continuous consumption of the DS must be concerned. Further safety assessment models including animals and humans should be performed to find safety dose of the DS. Abbreviations Used: ABTS: 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), DMEM: Dulbecco's Modified Eagle Medium, DMSO: Dimethyl sulfoxide, DPPH: 2,2-diphenyl-1-picrylhydrazyl, HLM: Human liver microsome, HLM: Human liver microsome, HPLC: High-performance liquid chromatography, IC50: Half inhibitory concentration, MDA: Malondialdehyde, OD: Optical density, PBMC: Peripheral blood mononuclear cell, RBC: Red blood cell, RPMI: Roswell Park Memorial Institute Medium, SC50: Halfmaximal radical scavenging concentration, SRB: Sulforhodamine B assay.

Introduction: The use of head hair for the identification of ABO blood groups using the absorption elution (AE) method requires time and expertise. Therefore, developing a new method which is time-saving and more straightforward using Near Infrared spectroscopy is interesting but to date the prior knowledge is insufficient.

Ethanolic extracts of 30 Thai medicinal plants, traditionally used as alternative treatments in diabetes, were evaluated for antioxidative activity by the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method. They were evaluated in vitro for oxidative stress by thiobarbituric acid-reactive substance (TBARS) assay in pooled plasma of diabetic patients compared to without treatment of the extracts (control). The extracts were also assayed for protein glycation. The results showed that five plants had strong antioxidant activity: Phyllanthus emblica Linn. (PE), Terminalia chebula Retz. (TC), Morinda citrifolia Linn. (MC), Kaempferia parviflora Wall. (KP) and Houttuynia cordata Thunb.(HC), respectively. Thirty plant extracts were good correlation between total antioxidant activity and antiradical activity by TBARS as well as by glycation (r = 0.856, p

Ethyl caffeate (EC), octyl caffeate(OC), benzyl caffeate(BC) and phenethyl caffeate(PC) were synthesized and evaluated for scavenging of superoxide anion, nitric oxide radical and 1,1-diphenyl-1-picrylhydrazyl radical (DPPH). Antioxidant activity was investigated with reducing power method. Pooled human liver microsome was used for investigating the effects on cytochrome P450 1A2 (CYP1A2) catalytic activities by using phenacetin as a substrate. Dixon and Cornish-Bowden plots were used for enzyme kinetic analysis. The EC, OC, BC and PC potentially inhibited superoxide anion, nitric oxide and DPPH radicals. IC(50) values of superoxide anion scavenging of EC, OC, BC and PC were 16.42, 79.83, 123.69 and 123.69 µg/ml, respectively. EC was more potent than OC and BC in terms of nitric oxide radical scavenger: IC(50) values of EC, OC and BC were 24.16, 37.34 and 52.64 µg/ml, respectively. In addition, the IC(50) values of EC, OC, BC and PC on DPPH radical scavenging were 70.00, 184.56, 285.34 and 866.54 µg/ ml, respectively. The IC(50) values of EC, OC, BC and PC on phenacetin O-deethylation were 124.98, 111.86, 156.68 and 31.05 µg/ml, respectively. Enzyme kinetics showed that the type of inhibition mechanism was mixed-type. The result of this study shows that caffeic acid ester analogues potentially scavenge free radicals and inhibit catalytic activity of CYP1A2. This may lead to important implications in the prevention of CYP1A2-mediated chemical carcinogenesis.

Previous studies presented evidence that plants contain antioxidants that have free radical-scavenging properties. Overproduction of free radicals leads to oxidative stress, a factor associated with a variety of diseases, such as diabetes. Cytochrome P450 2E1 enzymes (CYP2E1) are involved in drug metabolism in the liver and metabolism of DNA-reaction generating intra-mitochondrial ROS, which leads to micro- and macro-vascular pathology in diabetes. Plant-based chemicals can affect CYP2E1 enzymes and related defense mechanisms, possibly leading to protection against oxidative stress. We investigated the effect of Solanum torvum (ST) extracts on the inhibition of CYP2E1 activity in human liver microsomes. ST extract was analyzed for antioxidant activity by the ABTS method. Polyphenolic compounds were measured by the total phenol content using the Folin-Ciocalteau reagent. Flavonoid and tannin content were analyzed by standard methods. Oxidative stress was evaluated by measuring lipid peroxidation by TBARS and superoxide anion scavenging levels in plasma from diabetic patients. Results showed that 10 mg/ml of ST had CYP2E1 catalytic inhibiting activity (57.16 %). The IC50 value of CYP2E1 catalytic inhibiting activity level was 5.14 mg/ml by concentration in a dependent manner. One gram of concentrated ST extract had an antioxidant activity index of 3.68 mg of trolox and 360.53 mg of ascorbic acid equivalent. Effects on free radical-scavenging, as measured by TBARS and superoxide anion, showed IC50 values of 20.60 and 10.26 microg/ml, respectively. Polyphenolic compounds found included phenol, flavonoid and tannin, measuring 160.30, 104.36 and 65.91 mg/g, respectively. These results imply that ST is a natural source of polyphenolic antioxidants, which have cytochrome P450 2E1 enzyme inhibiting and free radical scavenging properties, as related to lipid peroxidation and superoxide anion activity. ST could potentially be used for reducing oxidative stress in diabetes. Study for usage as a conventional medicine, including dosage and chronic toxicity in humans, should be pursued.