Quick nuclear transportation of siRNA and in vivo hepatic ApoB gene silencing with galactose-bearing polymeric carrier.

Since previous studies have linked the genetic mutations of Apolipoprotein B (ApoB) to the low density lipoprotein (LDL) cholesterol levels, it can be believed that the knockdown of ApoB by siRNA silencing is a useful method to reduce the cardiovascular disease. However, the spontaneous uptake of siRNA is hindered, and thus vectors are necessary to aid its transfer into the cells. Among the synthetic non-viral vectors, cationic polymers are extensively investigated as possible candidates for efficient and specific gene delivery, because they can be easily modified to get different set of properties. Therefore, in this work a set of random copolymers with different molecular weight and composition were synthesized. These vectors present 2-(dimethylamino)ethyl methacrylate, as cationic monomer, and galactose units as liver-targeting moieties. From in vitro experiments, copolymers with monomer ratio and molecular weight about 0.1 and 80kDa, respectively, showed adequate transfection capabilities and displaying good cell viability, independently of the nature of the saccharides units. However, in the in vivo experiments in C57BL/6 high-fat-fed mice, a better blood compatibility and protection against degradation leading to better transfection by the random copolymers bearing galactose units was confirmed.

Production of a novel mannosylerythritol lipid containing a hydroxy fatty acid from castor oil by Pseudozyma tsukubaensis.

Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by various yeasts belonging to the genus Pseudozyma, which exhibit excellent surface activities as well as versatile biochemical activities. A study on P. tsukubaensis NBRC1940 as a mono-acetylated MEL (MEL-B) producer revealed that the yeast accumulated a novel glycolipid from castor oil at a yield of 22 g/L. Its main chemical structure was identified as 1-O-ß-(2'-O-alka(e)noyl-3'-O-hydroxyalka(e)noyl-6'-O-acetyl-D-mannopyranosyl)-D-erythritol designated as "new MEL-B." The new MEL-B, comprising a hydroxy fatty acid had a reduced surface tension of 28.5 mN/m at a critical micelle concentration (CMC) of 2.2×10⁻5 M in water. The observed CMC was 5-fold higher than that of conventional MEL-B. When conventional MEL-B was dispersed in water, it self-assembled to form the lamellar (L(α)) phase at a wide range of concentrations. In contrast, new MEL-B formed spherical oily droplets similar to the sponge (L3) phase, which is observed in aqueous solutions of di-acetylated MEL (MEL-A). The data suggest that the newly identified MEL-B is likely to have a different structure and interfacial properties compared to the conventional MELs, and could facilitate an increase in the application of glycolipid biosurfactants.

Genetic stability assessment of wWasabi plants regenerated from long-term cryopreserved shoot tips using morphological, biochemical and molecular analysis.

This study compared the effect of cryopreserved storage duration of wasabi shoot tips, which derived from the same in vitro mother-plant. We compared the survival of shoot tips and the genetic stability of regenerated plants originating from four experimental groups: shoot tips stored in a -150°C deep-freezer for 10 years; shoot tips stored in liquid nitrogen for 2 h; shoot tips treated with PVS2 vitrification solution; and untreated controls. No significant difference in survival was observed between the four experimental groups. Survival ranged between 93 and 100%. Genetic stability of plants regenerated from cryopreserved shoot tips was assessed over a period of 24 months using morphological, biochemical and molecular markers. While glucose, fructose and glutamic acid concentrations differed slightly between experimental groups after 16 months, these differences disappeared after 24 months. No significant differences were noted for the morphological markers studied (petiole length, shoot number and leaf index). No differences were observed in RAPD profiles obtained with the six primers tested.

Development of antimicrobial thermoplastic material from archaeal poly-γ-L-glutamate and its nanofabrication.

Here we describe a stoichiometric ion-complex of archaeal poly-γ-L-glutamate (L-PGA) and hexadecylpyridinium cation (HDP(+)), called PGAIC, which shows remarkable chemical resistance and potential as a novel functional thermoplastic. PGAIC films suppressed the proliferation of prokaryotic (Escherichia coli, Bacillus subtilis, Salmonella typhimurium, and Staphylococcus aureus) and eukaryotic (Saccharomyces cerevisiae) microorganisms. Moreover, its antifungal activity was demonstrated against a prevalent species of Candida (Candida albicans) and a filamentous fungus (Aspergillus niger). The minimal inhibitory concentrations were estimated as 0.25 mg mL(-1), and zones of growth inhibition appeared when PGAIC-coated polyethylene terephthalate (PET) films were placed in culture plates, whereas PET had very little effect on fungal growth. Soluble PGAIC thus shows promises as an antimicrobial and as a coating substrate. We also succeeded in synthesizing an L-PGA-based nanofiber using an ethanol solution of PGAIC.

[A case of long-term survival due to combined modality therapy for liver metastasis of colon cancer].

The patient was a 68-year-old man. Because sigmoid colon cancer and metastatic liver cancer was diagnosed in August 2009, an indwelling central venous port and sigmoid colon resection were implemented. The metastatic liver cancer was a huge tumor occupying the right hepatic lobe and caudate lobe. In consideration of the risk associated with the resection and the possibility of early recurrence, the postoperative chemotherapy was selected. He underwent 9 courses of bevacizumab (Bev)+FOLFOX. The tumor was observed to reduce but continued to occupy the right lobe and caudate lobe. At this point, the surgical treatment was selected because the tumor has been shrunk and there is no appearance of new metastases. In order to preserve residual liver function, he underwent percutaneous transhepatic portal embolization and then resection of the right lobe of the liver in February 2010. Although the Bev+FOLFOX treatment was started again after surgery as adjuvant chemotherapy, the metastatic liver cancer recurred in the remnant liver in August 2010. Because it was about 6 months from the first recurrence of liver resection, we decided to continue chemotherapy immediately without resection. However, the chemotherapy was insufficient to shrink the tumor, which increased because it was present at 3 locations in the liver. Therefore, partial hepatectomy at the 3 locations with positron-emission tomography was performed in February 2011. Since then, chemotherapy has not been performed in patients, and there is no recurrence as of March 2012. In the guideline for the treatment of liver metastasis of colorectal cancer, even though chemotherapy is currently developed, the surgical procedure is recommended for patients who are responsive to local therapy. If the cancer recur immediately after resection, it is difficult to decide whether to re-resect. We report the case in which the tumor-free status can be observed as a result of a combination of systemic chemotherapy and local therapy.

The moisturizing effects of glycolipid biosurfactants, mannosylerythritol lipids, on human skin.

Glycolipid biosurfactants, such as mannosylerythritol lipids (MELs), are produced by different yeasts belonging to the genus Pseudozyma and have been attracting much attention as new cosmetic ingredients owing to their unique liquid-crystal-forming and moisturizing properties. In this study, the effects of different MEL derivatives on the skin were evaluated in detail using a three-dimensional cultured human skin model and an in vivo human study. The skin cells were cultured and treated with sodium dodecyl sulfate (SDS), and the effects of different lipids on the SDS-damaged cells were evaluated on the basis of cell viability. Most MEL derivatives efficiently recovered the viability of the cells and showed high recovery rates (over 80%) comparable with that of natural ceramide. It is interesting that the recovery rate with MEL-A prepared from olive oil was significantly higher than that of MEL-A prepared from soybean oil. The water retention properties of MEL-B were further investigated on human forearm skin in a preliminary study. Compared with the control, the aqueous solution of MEL-B (5 wt%) was estimated to considerably increase the stratum corneum water content in the skin. Moreover, perspiration on the skin surface was clearly suppressed by treatment with the MEL-B solution. These results suggest that MELs are likely to exhibit a high moisturizing action, by assisting the barrier function of the skin. Accordingly, the yeast glycolipids have a strong potential as a new ingredient for skin care products.

Activation of fibroblast and papilla cells by glycolipid biosurfactants, mannosylerythritol lipids.

Mannosylerythritol lipids (MELs), the extracellular glycolipids produced from feedstock by yeasts belonging to the genus Pseudozyma, are the most promising biosurfactants known due to its versatile interfacial and biochemical actions. In order to broaden the application in cosmetics, the cell activating property of MELs was investigated using cultured fibroblast and papilla cells, and a three-dimensional cultured human skin model. The di-acetylated MEL (MEL-A) produced from soybean oil significantly increased the viability of the fibroblast cells over 150% compared with that of control cells. On the other hand, no cell activation was observed by the treatment with MEL-A produced from olive oil. The mono-acetylated MEL (MEL-B) hardly increased the cell viability. The viability of the fibroblast cells decreased with the addition of more than 1 microg/L of MELs, whereas the cultured human skin cells showed high viability with 5 microg/L of MELs. Interestingly, the papilla cells were dramatically activated with 0.001 microg/L of MEL-A produced from soybean oil: the cell viability reached at 150% compared with that of control cells. Consequently, the present MEL-A produced from soybean oil should have a potential as a new hair growth agent stimulating the papilla cells.

Glycolipid biosurfactants, mannosylerythritol lipids, repair the damaged hair.

Mannosylerythritol lipids (MELs), are produced from feedstock by the genus Pseudozyma, and are the most promising biosurfactants known due to its versatile interfacial and biochemical actions. In order to broaden the application in cosmetics, the hair care properties of MELs were investigated using damaged hair. On electron microscopic observation, the damaged hair was dramatically recovered with applying MEL-A and MEL-B. The tensile strength of the damaged hair increased by treatment with MEL-A (122.0 +/- 13.5 gf/p), MEL-B (119.4 +/- 7.6 gf/p) and ceramide (100.7 +/- 15.9 gf/p) compared with only lauryl glucoside (96.7 +/- 12.7 gf/p), indicating the advantage of MELs on hair care treatment. In addition, the average friction coefficient of the damaged hair was maintained after treatment with MEL-A (0.108 +/- 0.002), MEL-B (0.107 +/- 0.003) and the ceramide (0.111 +/- 0.003), although lauryl glucoside treatment increased the average friction coefficient (0.126 +/- 0.003). The increase of bending rigidity by treatment with lauryl glucoside (0.204 +/- 0.002) was prevented by treatment with MEL-A (0.129 +/- 0.002), MEL-B (0.176 +/- 0.003) and the ceramide (0.164 +/- 0.002). Consequently, MELs are proposed to be the new hair care ingredient, which are the highly useful agent for not only for the recovery of damaged hair but also for providing the smooth and flexible hair.

A yeast glycolipid biosurfactant, mannosylerythritol lipid, shows potential moisturizing activity toward cultured human skin cells: the recovery effect of MEL-A on the SDS-damaged human skin cells.

Mannosylerythritol lipids (MELs) are produced in large amounts from renewable vegetable oils by Pseudozyma antarctica, and are the most promising biosurfactants known due to its versatile interfacial and biochemical actions. In order to broaden the application in cosmetics and pharmaceuticals, the skin care property of MEL-A, the major component of MELs, was investigated using a three-dimensional cultured human skin model. The skin cells were cultured and treated with sodium dodecyl sulfate (SDS) solution of 1 wt%, and the effects of different lipids on the SDS-damaged cells were then evaluated on the basis of the cell viability. The viability of the damaged cells was markedly recovered by the addition of MEL-A in a dose-dependent manner. Compared to the control, MEL-A solutions of 5 wt% and 10 wt% gave the recovery rate of 73% and 91%, respectively, while ceramide solution of 1 wt% gave the rate of over 100%. This revealed that MEL-A shows a ceramide-like moisturizing activity toward the skin cells. Considering the drawbacks of natural ceramides, namely limited amount and high production cost, the yeast biosurfactants should have a great potential as a novel moisturizer for treating the damaged skin.

Production of a novel glycolipid biosurfactant, mannosylmannitol lipid, by Pseudozyma parantarctica and its interfacial properties.

The development of a novel glycolipid biosurfactant was undertaken using the high-level producers of mannosylerythritol lipids (MELs) such as Pseudozyma parantarctica, Pseudozyma antarctica, and Pseudozyma rugulosa. Besides the conventional MELs (MEL-A, MEL-B, and MEL-C), these yeasts produced an unknown glycolipid when they were cultivated in a medium containing 4% (w/v) olive oil and 4% (w/w) mannitol as the carbon source. The unknown glycolipid extracted from the culture medium of P. parantarctica JCM 11752(T) displayed the spot with lower mobility than that of known MELs on TLC and provided mainly two peaks identical to mannose and mannitol on high-performance liquid chromatography after acid hydrolysis. Based on structural analysis by (1)H and (13)C nuclear magnetic resonance, the novel glycolipid was composed of mannose and mannitol as the hydrophilic sugar moiety and was identified as mannosylmannitol lipid (MML). Of the strains tested, P. parantarctica JCM 11752(T) gave the best yield of MML (18.2 g/L), which comprised approximately 35% of all glycolipids produced. We further investigated the interfacial properties of the MML, considering the unique hydrophilic structure. The observed critical micelle concentration (CMC) and the surface tension at CMC of the MML were 2.6 x 10(-6) M and 24.2 mN/m, respectively. In addition, on a water-penetration scan, the MML efficiently formed not only the lamella phase (Lalpha) but also the myelins at a wide range of concentrations, indicating its excellent self-assembling properties and high hydrophilicity. The present glycolipid should thus facilitate the application of biosurfactants as new functional materials.

Identification of Pseudozyma graminicola CBS 10092 as a producer of glycolipid biosurfactants, mannosylerythritol lipids.

A basidiomycetous yeast, Pseudozyma graminicola CBS 10092, was found to accumulate a large amount of glycolipids in the cultured medium when grown on soybean oil as the sole carbon source. Based on thin layer chromatography, the extracellular glycolipids gave spots corresponding to those of mannosylerythritol lipids (MELs), which are highly functional and promising biosurfactants. From the structural characterization by 1H and 13C NMR, the main product was identified as 4-O-[(4'-mono-O-acetyl-2', 3'-di-O-alka(e)noyl)-beta-D-mannopyranosyl]-D-erythritol, which is a highly hydrophilic derivative of MELs known as MEL-C. According to high-performance liquid chromatography analysis, the main product, MEL-C, comprised approximately 85% of all the MELs, and the total amount reached approximately 10 g/L for 7 days. The fatty acids of the present MEL-C consisted of mainly C6, C8 and C14 acids, considerably different from those of MEL-C produced by other Pseudozyma strains such as P. antarctica and P. shanxiensis. The observed critical micelle concentration (CMC) and the surface-tension at CMC of the MEL-C were 4.0 x 10(-6) M and 24.2 mN/m, respectively, while those of MEL-A, the most intensively studied MEL, were 2.7 x 10(-6) M and 28.4 mN/m, respectively. This implied that the MEL-C has higher hydrophilicity than conventional MELs hitherto reported. In addition, on a water-penetration scan, the MEL-C efficiently formed the lamella phase (Lalpha) at a wide range of concentrations, indicating its excellent self-assembling properties. From these results, the newly identified MELs produced by P. graminicola are likely to have great potential for use in oil-in-water type emulsifiers and/or washing detergents, and would thus facilitate a broad range of applications for the promising yeast biosurfactants.

Enzymatic synthesis of arbutin undecylenic acid ester and its inhibitory effect on melanin synthesis.

Transesterification of arbutin and undecylenic acid vinyl ester was catalyzed by alkaline protease, Bioprase, in dimethylformamide to get arbutin derivative having undecylenic acid at 6-position of glucose moiety, 6-O-undecylenoyl p-hydroxyphenyl beta-D-glucopyranoside. The reaction rate increased with increase of arbutin concentration, and when its concentration was 0.9 M, the conversion rate was more than 90% under addition of 2 M undecylenic acid vinyl ester. The obtained arbutin ester significantly suppressed melanin production in murine B16 melanoma cells.

Effectiveness of two-step (consecutive) embryo transfer in patients who have two embryos on day 2: comparison with cleavage-stage embryo transfer.

OBJECTIVE: To evaluate the effectiveness, for patients who have only two embryos on day 2, of a two-step (consecutive) embryo transfer (ET) procedure in which a cleaved embryo is transferred on day 2 and a single blastocyst is transferred on day 5. DESIGN: Observational comparative study. SETTING: Private IVF clinic. PATIENT(S): Ninety two-step ET cycles were performed in patients who had two embryos on day 2 (two-step group). Ninety day-2 ET cycles were performed in age- and infertility-matched patients who had two embryos on day 2 (control group). INTERVENTION(S): Cleaved-ET, extended culture of one embryo, and a second transfer of a blastocyst. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULT(S): The pregnancy and implantation rates in the two-step group (respectively 33.3% and 17.2%) were significantly higher than those in the control group (18.9% and 9.4%). Thirty-nine of the patients in the two-step group (43.3%) could not proceed to the second step of ET because no viable blastocyst could be obtained, but four of them conceived anyway. CONCLUSION(S): Taking advantage of both day-2 ET and blastocyst transfer, two-step ET may be an effective option for ET in patients who have an insufficient number of embryos.

Enzymatic transesterification of purine nucleoside having a low solubility in organic medium.

Enzymatic transesterification of guanosine having low solubility against organic solvent was examined. For the transesterification between guanosine and divinyl adipate catalyzed by alkaline protease from Bacillus (Bioprase), DMSO was added to DMF to increase the solublility of the nucleoside, and the conversion rate of guanosine to the vinyl guanosine ester was less than 30%. To overcome the reversible inactivation of enzyme by hydrophilic organic solvents, the reaction was carried out with 10% (v/v) water. The transesterification reaction was effectively catalyzed in DMF/DMSO in the presence of water and the conversion rate increased ca. 70% after 7 d reaction. The result shows that the water effect of Bioprase would be a useful method for the synthesis of low solublility nucleoside esters.

Enzymatic synthesis of hydrophilic undecylenic acid sugar esters and their biodegradability.

To enhance water solubility of 10-undecylenic acid, which has anti-fungus, anti-bacterial and anti-virus activity, D-glucose, trehalose and sucrose were regioselectively esterified with vinyl 10-undecylenic acid ester in dimethyl formamide by a commercial protease, Bioprase conc., from Bacillus subtilis. 6-O-(10-Undecylenoyl) D-glucose, 6-O-(10-undecylenoyl) trehalose and 1'-O-(10-undecylenoyl) sucrose were obtained. The influence of structural variation by changing the sugar moiety was analyzed the surface tension and biodegradability.