Thermal Processing Effects on Rice Characteristics

Whole kernels of four cultivars of milled rice were treated under different conditions according to our traditional methods such as boiling, steaming, autoclaving or roasting with sand. During the vari ous processing conditions, the moisture contents of the kernel , heating temperatures, pressures and heating times were varied. In this paper, the physicochemical properties of those processed samples were investigated and compared. Based on degree of gelatinization , water absorption index , water solubility index , swelling power, viscoamylograms and X-ray diffraction patterns, the propenies of waxy rice samples arc different from that of non -waxy rice samples. They are also different even among the non-waxy rice samples. Besides , each processed sample under diverse treatments has its own properties. In boiled samples, the starch granules almost gelatinized to form a film-like gel substance, whereas in othe r processed samples, ungelatinized starch granules were noticeable

Synthetic Strategies to Access Biologically Important Fluorinated Motifs: Fluoroalkenes and Difluoroketones

Fluorine plays an important role in drug design, because of some unique features imparted by fluorine. The incorporation of fluorine into small molecules can modulate molecular physicochemical properties, metabolic stability, lipophilicity, and binding affinity to the target proteins. However, few fluorinated molecules are biosynthesized by enzymes. This means incorporating fluorine into the molecules relies on synthetic methods. Thus, efficient synthetic strategies to access the molecules bearing a variety of privileged fluorinated moieties are important for drug discovery. Fluoroalkenes are an isopolar and isosteric mimic of an amide bond with distinct biophysical properties, including decreased H-bond donating and accepting abilities, increased lipophilicity, and metabolic stability. Moreover, fluoroalkenes can also serve as probes for conducting conformational analyses of amides. These potential applications require the development of efficient methods to access fluoroalkenes. In chapter 2, a Shapiro fluorination strategy to access peptidomimetic fluoroalkenes is demonstrated. The Shapiro fluorination reactions convert a ketone into a fluoroalkene in one or two steps. Moreover, this method uses inexpensive and readily available reagents, and no transition metals are involved in the reactions. Thus, it provides an operation-simple alternative to access fluoroalkenes in medicinal chemistry. a,a-difluoroketones represent a privileged substructure in medicinal chemistry, and serves as inhibitors to many hydrolytic enzymes, such as serine and aspartyl proteases. From chapters 3 to 5, palladium-catalyzed decarboxylative methods are developed for accessing a-alkyl- and a-aryl-a,a-difluoroketones. This decarboxylative strategy overcomes two major challenges associated with alkylation reactions of a,a-difluoroketone enolates. Chapter 3 demonstrates that decarboxylation regioselectively generates a,a-difluoroketone enolates, which are difficult to access by base deprotonation. Moreover, palladium catalysis enables the coupling of the a,a-difluoroketone enolate with benzylic electrophiles to form a key C(a)–C(sp3) bond. In chapter 4, an orthogonal catalytic system is developed for accessing linear and branched a-allyl-a,a-difluoroketones. Two distinct mechanisms are involved in the formation of the regioisomers. Chapter 5 describes a base-mediated selective para-C–H difluoroalkylation of arenes, which represents a different strategy for para-C–H functionalization of arenes compared to the known methods. These decarboxylative coupling reactions provide structurally diverse a,a-difluoroketone derivatives, and should be useful for accessing potential biological probes and therapeutics

Fluorination Enables a Ligand-Controlled Regiodivergent Palladium-Catalyzed Decarboxylative Allylation Reaction to Access α,α-Difluoroketones

This is the peer reviewed version of the following article: Yang, M., Orsi, D. L., & Altman, R. A. (2015). Fluorination Enables a Ligand-Controlled Regiodivergent Palladium-Catalyzed Decarboxylative Allylation Reaction to Access α,α-Difluoroketones. Angewandte Chemie (International Ed. in English), 54(8), 2361–2365. http://doi.org/10.1002/anie.201410039, which has been published in final form at doi.org/10.1002/anie.201410039. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.α,α-Difluoroketones possess unique physicochemical properties that are useful for developing therapeutics and probes for chemical biology. In order to access the α-allyl-α,α-difluoroketone substructure, complementary Pd-catalyzed decarboxylative allylation reactions were developed to provide linear and branched α-allyl-α,α-difluoroketones. For these orthogonal processes, the regioselectivity was uniquely controlled by fluorination of the substrate and the structure of ligand

IsaB Inhibits Autophagic Flux to Promote Host Transmission of Methicillin-Resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major nosocomial pathogen that is widespread in both health-care facilities and in the community at large, as a result of direct host-to-host transmission. Several virulence factors are associated with pathogen transmission to naive hosts. Immunodominant surface antigen B (IsaB) is a virulence factor that helps Staphylococcus aureus to evade the host defense system. However, the mechanism of IsaB on host transmissibility remains unclear. We found that IsaB expression was elevated in transmissible MRSA. Wild-type isaB strains inhibited autophagic flux to promote bacterial survival and elicit inflammation in THP-1 cells and mouse skin. MRSA isolates with increased IsaB expression showed decreased autophagic flux, and the MRSA isolate with the lowest IsaB expression showed increased autophagic flux. In addition, recombinant IsaB rescued the virulence of the isaB deletion strain and increased the group A streptococcus (GAS) virulence in vivo. Together, these results reveal that IsaB diminishes autophagic flux, thereby allowing MRSA to evade host degradation. These findings suggest that IsaB is a suitable target for preventing or treating MRSA infection

Shikonin enhances efficacy of a gene-based cancer vaccine via induction of RANTES

<p>Abstract</p> <p>Background</p> <p>Shikonin, a phytochemical purified from <it>Lithospermum erythrorhizon</it>, has been shown to confer diverse pharmacological activities, including accelerating granuloma formation, wound healing, anti-inflammation and others, and is explored for immune-modifier activities for vaccination in this study. Transdermal gene-based vaccine is an attractive approach for delivery of DNA transgenes encoding specific tumor antigens to host skin tissues. Skin dendritic cells (DCs), a potent antigen-presenting cell type, is known to play a critical role in transmitting and orchestrating tumor antigen-specific immunities against cancers. The present study hence employs these various components for experimentation.</p> <p>Method</p> <p>The mRNA and protein expression of RANTES were detected by RT-PCR and ELISA, respectively. The regional expression of RANTES and tissue damage in test skin were evaluated via immunohistochemistry assay. Fluorescein isothiocyanate sensitization assay was performed to trace the trafficking of DCs from the skin vaccination site to draining lymph nodes. Adjuvantic effect of shikonin on gene gun-delivered human gp100 (hgp100) DNA cancer vaccine was studied in a human gp100-transfected B16 (B16/hgp100) tumor model.</p> <p>Results</p> <p>Among various phytochemicals tested, shikonin induced the highest level of expression of RANTES in normal skin tissues. In comparison, mouse RANTES cDNA gene transfection induced a higher level of mRANTES expression for a longer period, but caused more extensive skin damage. Topical application of shikonin onto the immunization site before gene gun-mediated vaccination augmented the population of skin DCs migrating into the draining lymph nodes. A hgp100 cDNA gene vaccination regimen with shikonin pretreatment as an adjuvant in a B16/hgp100 tumor model increased cytotoxic T lymphocyte activities in splenocytes and lymph node cells on target tumor cells.</p> <p>Conclusion</p> <p>Together, our findings suggest that shikonin can effectively enhance anti-tumor potency of a gene-based cancer vaccine via the induction of RANTES expression at the skin immunization site.</p

COMPARISON OF TORSO TWIST BETWEEN SLAP HIT AND ORDINARY HIT IN SOFTBALL BATTING

Softball batters take advantage of slap hit, by positioning the batters much closer to the first base. The purpose of this study was to compare the difference of torso twist between a slap hit and an ordinary hit in softball batting. Ten female college softball batters performed slap hits and ordinary hits. Reflective markers were placed on specific landmarks for each subject and VICON motion analysis system was used to record the hits. Slap hits showed less backward rotation during the torso wind-up phase while ordinary hit showed more forward rotation during the torso follow-through phase. No difference on trunk rotation was found at impact. The findings of this study suggested that the restricted backward torso twist during the wind-up phase and the limited forward torso twist during the follow-through phase should be taken into consideration in slap hits

Topological surface electronic states in candidate nodal-line semimetal CaAgAs

We investigate systematically the bulk and surface electronic structure of the candidate nodal-line semimetal CaAgAs by angle resolved photoemission spectroscopy and density functional calculations. We observed a metallic, linear, non-$k_z$-dispersive surface band that coincides with the high-binding-energy part of the theoretical topological surface state, proving the topological nontriviality of the system. An overall downshift of the experimental Fermi level points to a rigid-band-like $p$-doping of the samples, due possibly to Ag vacancies in the as-grown crystals.Comment: 6 pages, 5 figure

Contagion and downside risk in the REIT market during the subprime mortgage crisis

This study empirically tests the contagion effects in stock and real estate investment trust (REIT) markets during the subprime mortgage crisis by using daily stock- and REIT-markets data from the following countries and international bodies: the United States, the European Union, Japan, Hong Kong, Singapore, Australia, and the global REIT market. We found a significant and positive dynamic conditional correlation (DCC) coefficient between stock returns and REIT returns. The results revealed that the REIT markets responded early to market shocks and that the variances were higher in the post-crisis period than in the pre-crisis period. Evidence supporting the contagion effects includes increases in the means of the DCC coefficients during the post-crisis period. The Japanese and Australian REIT markets possess the lowest time-varying downside systematic risks. We also demonstrated that the “DCC E-beta” captures more significant downside linkages between market portfolios and expected REIT returns than does the standard CAPM beta

Serum repressing efflux pump CDR1 in Candida albicans

BACKGROUND: In the past decades, the prevalence of candidemia has increased significantly and drug resistance has also become a pressing problem. Overexpression of CDR1, an efflux pump, has been proposed as a major mechanism contributing to the drug resistance in Candida albicans. It has been demonstrated that biological fluids such as human serum can have profound effects on antifungal pharmacodynamics. The aim of this study is to understand the effects of serum in drug susceptibility via monitoring the activity of CDR1 promoter of C. albicans. RESULTS: The wild-type C. albicans cells (SC5314) but not the cdr1/cdr1 mutant cells became more susceptible to the antifungal drug when the medium contained serum. To understand the regulation of CDR1 in the presence of serum, we have constructed CDR1 promoter-Renilla luciferase (CDR1p-RLUC) reporter to monitor the activity of the CDR1 promoter in C. albicans. As expected, the expression of CDR1p-RLUC was induced by miconazole. Surprisingly, it was repressed by serum. Consistently, the level of CDR1 mRNA was also reduced in the presence of serum but not N-acetyl-D-glucosamine, a known inducer for germ tube formation. CONCLUSION: Our finding that the expression of CDR1 is repressed by serum raises the question as to how does CDR1 contribute to the drug resistance in C. albicans causing candidemia. This also suggests that it is important to re-assess the prediction of in vivo therapeutic outcome of candidemia based on the results of standard in vitro antifungal susceptibility testing, conducted in the absence of serum