Homogenizing Silicon Domains in SiOx Anode during Cycling and Enhancing Battery Performance via Magnesium Doping.

SiOx (x ≈ 1) is one of the most promising anode materials for application in secondary lithium-ion batteries because of its high theoretical capacity. Despite this merit, SiOx has a poor initial Coulombic efficiency, which impedes its widespread use. To overcome this limitation, in this work, we successfully demonstrate a novel synthesis of Mg-doped SiOx via a mass-producible physical vapor deposition method. The solid-state reaction between Mg and SiOx produces Si and electrochemically inert magnesium silicate, thus increasing the initial Coulombic efficiency. The Mg doping concentration determines the phase of the magnesium silicate domains, the size of the Si domains, and the heterogeneity of these two domains. Detailed electron microscopy and synchrotron-based analysis revealed that the nanoscale homogeneity of magnesium silicates driven by cycling significantly affected the lifetime. We found that 8 wt % Mg is the most optimized concentration for enhanced cyclability because MgSiO3, which is the dominant magnesium silicate composition, can be homogeneously mixed with silicon clusters, preventing their aggregation during cycling and suppressing void formation.

Evaluation of cytolytic activity and phenotypic changes of circulating blood immune cells in patients with colorectal cancer by a simple preparation of peripheral blood mononuclear cells.

PURPOSE: This study aimed to assess the cytolytic activity and the phenotype of circulating blood immune cells in cancer patients by using a simple preparation of peripheral blood mononuclear cells (PBMCs). METHODS: Peripheral blood was obtained from 94 diagnosed colorectal cancer (CRC) patients and 112 healthy donors. PBMCs were cocultured with K562 cells for 2 hours and lactate dehydrogenase released from the dead K562 cells was measured by using a spectrophotometer. Meanwhile, PBMCs were stained with fluorescence conjugated monoclonal antibodies (mAbs) and analyzed by flow cytometry. RESULTS: The cytolytic activity of PBMCs were significantly different between CRC patient and healthy groups (8.82% ± 3.84% vs. 17.51% ± 8.57%; P < 0.001). However, no significant difference in the cytolytic activity was observed after surgery in the CRC patient group (before surgery, 8.82% ± 3.84% vs. after surgery, 9.95% ± 4.94%; P = 0.326). In addition, the percentage of peripheral blood natural killer cells was significantly higher in the preoperative patient group than in the healthy group (19.97% ± 11.51% vs. 15.60% ± 5.77%, P = 0.041). In contrast, the percentage of peripheral blood lymphocytes was lower in the preoperative patient group than in the healthy group (28.41% ± 8.31% vs. 36.4% ± 8.6%, P < 0.001). CONCLUSION: These results demonstrate that circulating blood immune cells of CRC patients are functionally impaired and undergo an immunophenotypic perturbation, and show that a simple preparation of PBMCs can be useful to evaluate cellular immunity in cancer.

The right posterior bile duct anatomy of the donor is important in biliary complications of the recipients after living-donor liver transplantation.

OBJECTIVE: To evaluate the influence of the anatomy of the right posterior bile duct (RPBD) of the donor on biliary complications in the recipients after living-donor liver transplantation (LDLT) using right hemi-liver grafts. BACKGROUND DATA: During living-donor right hepatectomy, the RPBD was often exposed to the dissection plane. We hypothesized that biliary complications after anastomosis were increased in these cases because of potential injury to the RPBD. METHODS: A total of 169 LDLTs using right hemi-liver grafts, with type I (typical) and type II (trifurcation) anatomy in conventional biliary classification, were retrospectively investigated. The patients were newly classified based on the confluence pattern of the RPBD. The patients were firstly divided into infraportal (IP, n = 12) and supraportal (SP, n = 157) types. SP type was subdivided into 3 groups: type A [ultrashort right bile duct (RBD), n = 20], type B (short RBD, n = 128), and type C (long RBD, n = 9). Type B was further subdivided into B-S (short caudal segment of the RPBD, n = 109) and B-L (long caudal segment of the RPBD, n = 19). RESULTS: The biliary complication rate was 0% in type IP and type C, 40% in type A, 17.6% in type B-S, and 52.6% in type B-L (P < 0.01). In multivariate analysis, a new grouping of the RBD was a significant risk factor for biliary complications in LDLT. CONCLUSIONS: The anatomy of the RPBD of the donor influenced the biliary outcome in the recipients. A short RBD and a long caudal segment of the RPBD of the donor were significant risk factors for biliary complications in LDLT.

[Could patients who underwent hepatic resection due to hepatocellular carcinoma with high alpha-fetoprotein be monitored for recurrence by alpha-fetoprotein level?].

BACKGROUND/AIMS: The follow-up strategy after hepatectomy for hepatocellular carcinoma (HCC) usually depends on the experience of physician, resulting in frequent imaging studies, which leads to increased cost. Hence, we investigated the role of monitoring alpha-fetoprotein (AFP) levels after hepatectomy in patients with preoperative high AFP. METHODS: From January 2000 to December 2004, 66 patients who underwent curative hepatectomy due to HCC with preoperative AFP level > 400 ng/mL were reviewed. Changes in AFP level after the operation were investigated. The recurrence was suspected in case of two consecutive increase of AFP over cut-off value. Cut-off value was determined by ROC curve. All patients were divided into 2 groups: patients who met the definition (Group S) and those who didn't (Group D). RESULTS: AFP level of 20 ng/ml was proposed as the cut-off value for diagnosis of recurrence by ROC curve. Thirty two patients who didn't have the AFP level decreased below 20 ng/ml after the resection had HCC recurred, whereas 16 out of 34 patients who had AFP decreased had tumor recurrence. The AFP level of patients without recurrence was kept below 20 ng/ml during the follow-up. The AFP level of 44 out of 48 recurred patients increased over 20 ng/ml upon recurrence. By definition, group D were 5 patients. In 4 patients of group D, the AFP level didn't increase above 20 ng/ml upon recurrence. These patients had HCC and they recurred 1 year after the surgery. CONCLUSIONS: In patients with preoperative AFP level > 400 ng/ml, the AFP level tended to increase above 20 ng/ml at recurrence mostly within 1 year. Hence, we proposed that these patients could be monitored by only AFP until 1 year after surgery.

Biological synthesis of 7-O-methyl Apigenin from naringenin using escherichia coli expressing two genes.

Within the secondary metabolite class of flavonoids, which consist of more than 10,000 known structures, flavones define one of the largest subgroups. The diverse function of flavones in plants as well as their various roles in the interaction with other organisms offers many potential applications including in human nutrition and pharmacology. We used two genes, flavone synthase (PFNS-1) that converts naringenin into apigenin and a flavone 7-O-methyltransferase gene (POMT-7) that converts apigenin into 7-O-methyl apigenin, to synthesize 7-O-methyl apigenenin from naringenin. The PFNS-1 gene was subcloned into the E. coli expression vector pGEX and POMT-7 was subcloned into the pRSF vector. Since both constructs contain different replication origins and selection markers, they were cotransformed into E. coli. Using E. coli transformants harboring both PFNS-1 and POMT-7, naringenin could be converted into 7-O-methyl apigenin, genkwanin.

Formation of flavone di-O-glucosides using a glycosyltransferase from Bacillus cereus.

Microbial UDP-glycosyltransferases can convert many small lipophilic compounds into glycons using uridinediphosphate- activated sugars. The glycosylation of flavonoids affects solubility, stability, and bioavailability. The gene encoding the UDP-glycosyltransferase from Bacillus cereus, BcGT-3, was cloned by PCR and sequenced. BcGT-3 was expressed in Escherichia coli BL21 (DE3) with a glutathione S-transferase tag and purified using a glutathione Stransferase affinity column. BcGT-3 was tested for activity on several substrates including genistein, kaempferol, luteolin, naringenin, and quercetin. Flavonols were the best substrates for BcGT-3. The enzyme dominantly glycosylated the 3-hydroxyl group, but the 7-hydroxyl group was glycosylated when the 3-hydroxyl group was not available. The kaempferol reaction products were identified as kaempferol-3-O-glucoside and kaempferol- 3,7-O-diglucoside. Kaempferol was the most effective substrate tested. Based on HPLC, LC/MS, and NMR analyses of the reaction products, we conclude that BcGT-3 can be used for the synthesis of kaempferol 3,7-O-diglucose.

Retraction: Homology Modeling and Site-directed Mutagenesis of Uridine Diphosphate Dependent Glycosyltrasferase 706D1 Reveal an Important Residue for Its Enzymatic Reaction.

The paper entitled "Homology Modeling and Site-directed Mutagenesis of Uridine Diphosphate Dependent Glycosyltrasferase 706D1 Reveal an Important Residue for Its Enzymatic Reaction" by Young Min Jeon et al, which was published online on 16 October 2008, has been withdrawn at the authors' request.

Labdane-type diterpenes active against acne from pine cones (Pinus densiflora).

Bioassay-guided extraction and fractionation of the aqueous methanolic extract of the cones of Pinus densiflora (Pinaceae) afforded one new labdane-type diterpene aldehyde, 15-nor-14-oxolabda-8(17),12 E-diene-18-oic acid, along with eight known diterpenes. Their structures were elucidated using spectroscopic methods as well as by comparison with previously reported data. The isolates showed antibacterial (Propionibacterium acnes) and antifungal activities.

A facile and simple method for the preparation of copoly(TEAMPS/VP)/silver nanocomposites for the humidity-sensing membranes.

We developed a simple method for the preparation of polyelectrolyte/silver nanocomposites, where silver nanoparticles were dispersed in a polyelectrolyte. Copoly(TEAMPS/VP)/silver (w/w=100/0, 100/1, 100/2, 100/3 and 100/4) nanocomposites were obtained by a thermal decomposition reaction of silver carbamate complex at 130 degrees C, and well-dispersed silver colloids were stabilized by copolymer of tetraethylammonium 2-acrylamido-2-methyl-1-propanesulfonate (TEAMPS) and N-vinylpyrrolidone (VP). A dark brown solution in its UV-vis absorption spectrum showed surface plasmon resonance absorption bands at 420 nm in solution. The silver precursor and the resulting polyelectrolyte/Ag nanocomposite was characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), infrared (IR), transmission electron microscopy (TEM). In addition the humidity-sensing properties using copoly(TEAMPS/VP)/Ag nanocomposite films were examined.