Mechanisms of Significant Precipitation Hardening in a Medium Carbon Bainitic Steel by Complex Nanocarbides Composed of Nb, Ti and V

Precipitation-hardening behavior of various medium carbon bainitic steels with added elements of Nb, Ti and V was systematically investigated. Complex nanocarbides composed of Nb, Ti and V precipitated after aging in the steel with multiple additions of all the elements, whereas those with added individual elements were simple MC types. The amount of precipitation hardening (ΔHv) after aging at 873 K of the former steel was approximately 90 ΔHv, while those of the latter were less than 40 ΔHv at best. Therefore, significant precipitation hardening took place by multiple element addition. The different amount of precipitation hardening depending on added elements was reasonably understood by considering misfit parameters between carbides and ferrite matrix

Down-regulatory mechanism of mammea E/BB from Mammea siamensis seed extract on Wilms' Tumor 1 expression in K562 cells.

BackgroundWilms' tumor 1 (WT1) is a biological marker for predicting leukemia progression. In this study, mammea E/BB, an active compound from Saraphi (Mammea siamensis) seed extract was examined for its effect on down-regulatory mechanism of WT1 gene expression, WT1 protein and mRNA stability, and cell proliferation in K562 cell line.MethodsM. siamensis seeds were obtained from the region of Chiang Mai (North of Thailand). Mammea E/BB was extracted from seeds of M. siamensis. WT1 protein expression and stability were evaluated by Western blot analysis. WT1 mRNA stability was assessed by qRT-PCR. WT1-DNA binding and WT1 promoter activity were assayed by ChIP assay and luciferase-reporter assay, respectively. Cell cycle arrest was studied by flow cytometry.ResultsTreatment with mammea E/BB led to down-regulation of WT1 expression. The suppression of WT1 expression did not involve protein and mRNA degradation. Rather, WT1 protein was down-regulated through disruption of transcriptional auto-regulation of the WT1 gene. Mammea E/BB inhibited WT1-DNA binding at the WT1 promoter and decreased luciferase activity. It also disrupted c-Fos/AP-1 binding to the WT1 promoter via ERK1/2 signaling pathway and induced S phase cell cycle arrest in K562 cells.ConclusionMammea E/BB had pleotropic effects on kinase signaling pathways, resulting in inhibition of leukemia cell proliferation

PREPARATION AND CHARACTERIZATION OF MODIFIED COLORED RICE AS A GELLING CARRIER FOR BUCCAL DRUG DELIVERY SYSTEM

Objective: The present study was to prepare and characterize the chemically modified rice from the colored rice grains as a gelling agent for buccal gel preparation.Methods: The colored rice grains from two different varieties, Homnil (HN) and Kum-Doisket (KD), were compared. The chemically modified rice was prepared by etherification. The obtained modified samples were investigated for their solid structure using scanning electron microscope and X-ray diffractometer. The solubility and swelling property in water were also investigated. Rice gel bases and drug loading gels were prepared by hydration and levigation methods, respectively. The obtained gels were evaluated for rheological, adhesive, and drug release properties.Results: The HN and KD rice varieties yielded modified rice powders with different morphology, crystallinity, aqueous solubility, and swelling characteristics. The amylose content in different rice variety significantly affected the internal crystalline structure of the rice powders and adhesive as well as rheological properties of the respectively derived gels. Rheological behavior of the colored rice gels was pseudoplastic non-Newtonian flow. The drug release property of HN and KD gels was influenced by swelling property of the gel base. Different gel properties reflected the different rice varieties used for gel preparation.Conclusion: The variety of rice can affect the properties of the gelling agent from colored rice grains. The chemical modified colored rice grain can be feasible to be the good gelling agents in Pharmaceutical buccal gel preparation.Keyword: Rice variety, Rice gel, buccal gel, Amylose content, Carbamide peroxid

ANTIFUNGAL EFFECT OF HYPTIS SUAVEOLENS OIL MICROEMULSION BASED CARBOXYMETHYL MUNGBEAN GEL FOR TOPICAL DELIVERY

Objective: Conventional topical antifungal formulations limit the effectiveness of antifungal therapy. The aim of this study was to formulate effective antifungal microemulsion of H. suaveolens oil based carboxymethyl mungbean (CMMS) gel.Methods: H. suaveolens oil was obtained by steam distillation. Standard of H. suaveolens oil was performed by gas chromatography mass spectrometry (GC/MS). A high-viscosity CMMS was prepared and its mucoadhesive property was determined using modified USP dissolution test apparatus. H. suaveolens oil microemulsion based CMMS gel as transdermal drug carrier was then developed. Finally, in vitro drug release study and antifungal activity were determined.Results: GC/MS analysis exhibited that b-Caryophyllene, Sabinene and Limonene are the major components of H. suaveolens oil. CMMS gel revealed good mucoadhesive potential which depended on pH of the medium. A higher retention time in pH 4.5 medium than pH 10 medium was observed. Clotrimazole-loaded H. suaveolens oil microemulsions based CMMS gel was successful prepared and in vitro sustained release of clotrimazole was determined. Clotrimazole-loaded H. suaveolens oil microemulsions based CMMS gel had potent antifungal activity against all studied dermatophytes and Candida albican with higher inhibition zone than H. suaveolens oil microemulsions based CMMS gel, H. suaveolens oil and commercial clotrimazole cream.Conclusion: H. suaveolens oil microemulsions based CMMS gel present promising as an effective alternative for topical delivery of antifungal agents.Â

Theta-Range Oscillations in Stress-Induced Mental Disorders as an Oscillotherapeutic Target

Emotional behavior and psychological disorders are expressed through coordinated interactions across multiple brain regions. Brain electrophysiological signals are composed of diverse neuronal oscillations, representing cell-level to region-level neuronal activity patterns, and serve as a biomarker of mental disorders. Here, we review recent observations from rodents demonstrating how neuronal oscillations in the hippocampus, amygdala, and prefrontal cortex are engaged in emotional behavior and altered by psychiatric changes such as anxiety and depression. In particular, we focus mainly on theta-range (4–12 Hz) oscillations, including several distinct oscillations in this frequency range. We then discuss therapeutic possibilities related to controlling such mental disease-related neuronal oscillations to ameliorate psychiatric symptoms and disorders in rodents and humans

Rigid spin-labeled nucleoside Ç: a nonperturbing EPR probe of nucleic acid conformation

Rigid spin-labeled nucleoside Ç, an analog of deoxycytidine that base-pairs with deoxyguanosine, was incorporated into DNA oligomers by chemical synthesis. Thermal denaturation experiments and circular dichroism (CD) measurements showed that Ç has a negligible effect on DNA duplex stability and conformation. Nucleoside Ç was incorporated into several positions within single-stranded DNA oligomers that can adopt two hairpin conformations of similar energy, each of which contains a four-base loop. The relative mobility of nucleotides in the alternating C/G hairpin loops, 5′-d(GCGC) and 5′-d(CGCG), was determined by electron paramagnetic resonance (EPR) spectroscopy. The most mobile nucleotide in the loop is the second one from the 5′-end, followed by the third, first and fourth nucleotides, consistent with previous NMR studies of DNA hairpin loops of different sequences. The EPR hairpin data were also corroborated by fluorescence spectroscopy using oligomers containing reduced Ç (Çf), which is fluorescent. Furthermore, EPR spectra of duplex DNAs that contained Ç at the end of the helix showed features that indicated dipolar coupling between two spins. These data are consistent with end-to-end duplex stacking in solution, which was only observed when G was paired to Ç, but not when Ç was paired with A, C or T

ANTI-INFLAMMATORY, ANTIBACTERIAL, AND ANTIOXIDANT ACTIVITIES OF THAI MEDICINAL PLANTS

Objective: Acacia farnesiana (L.) Willd, Senna alata (L.) Roxb., Sesbania grandiflora (L.) Pers., Syzygium cumini (L.) Skeels and Tabernaemontana divaricate (L.) R. Br. ex Roem. & Schult. are used in Thai traditional remedies to treat various disorders ranging from fever and pain to inflammation or microbial infections. However, there is a lack of scientific data on some of the biological activities. Methods: The present study was designed to compare the antibacterial, antioxidant, and anti-inflammatory effects of the five plants. Ethanolic extracts of A. farnesiana, S. alata, S. grandiflora, S. cumini, T. divaricata were firstly compared for antioxidant activity using free radical scavenging of 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power tests. Antibacterial activity indicated by minimum bactericidal concentration (MBC) was determined using broth and agar dilution tests against aerobic and anaerobic pathogenic bacterial strains. The anti-inflammatory activity was evaluated in vitro using a lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage model.Results: All the tested extracts exerted antioxidant, antibacterial and anti-inflammatory effects. S. cumini and S. grandiflora extracts showed the highest free radical scavenging activities. S. cumini extract showed the highest activity against Staphylococcus aureus, S. epidermidis, and Corynebacterium diphtheriae. All extracts exerted anti-inflammatory activity as indicated by a reduction of interleukin (IL)-6 secretion and/or tumor necrosis factor (TNF)-α production.Conclusion: Taken together, these findings suggest that the tested plants can be developed as effective herbal remedies for the treatment and prevention of inflammation or associated diseases as well as against bacterial infections.Â

BIOACTIVITIES OF THE THAI MEDICINAL AND EDIBLE PLANTS C. CAJAN, M. CITRIFOLIA AND O. AMERICANUM

Objective: Inflammation and oxidative stress are closely related and play a role in various diseases. If an infectious component plays a role, an antibacterial effect is of advantage. Thus, natural remedies which combine different bioactivities have a broader range of application.Methods: Here we elucidate the anti-inflammatory, antioxidant and antibacterial effects of three edible and traditionally used Thai plants including leaves of Cajanus cajan, Morinda citrifolia and Ocimum americanum.Results: The extracts exerted significant anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated macrophages. C. cajan extract shows a broad spectrum of antibacterial activity against Gram positive and negative, aerobic and anaerobic bacteria, whereas M. citrifolia and O. americanum possess antibacterial activity only against anaerobic bacteria. Extracts of all three plants showed significant antioxidant effects.Conclusion: The three plants are potential herbal remedies or supplements for functional food for the treatment and prevention of inflammation, oxidative imbalance, and bacterial infections or associated diseases.Â

生薬に付着する真菌類の実態と生薬品質への影響

取得学位：博士(薬学)，学位授与番号：博甲第631号，学位授与年月日：平成16年3月25日,学位授与年：200