Ab initio quantum mechanics/molecular mechanics method with periodic boundaries employing Ewald summation technique to electron-charge interaction: Treatment of the surface-dipole term.

We have developed a combined quantum mechanics/molecular mechanics (QM/MM) method with periodic boundary condition (PBC) treatment of explicit electron-charge interactions in a theoretically rigorous manner, for an accurate description of electronic structures for molecules in the condensed phase. The Ewald summation technique is employed for the calculation of the one-electron Hamiltonian in an ab initio framework. We decompose the Coulomb interactions into two components: those within the same cell and those between different cells. The former is calculated in the same way as the conventional QM/MM calculation for isolated systems; this article focuses on our novel method for calculating the latter type of Coulomb interactions. The detailed formulation of the Hamiltonian of this new QM/MM-PBC method, as well as the necessary one-electron integrals and their gradients, is given. The novel method is assessed by applying it to the dilute water system and a system with a coumarin molecule in water solvent; it successfully reproduces the electronic energies, frontier orbital energies, and Mulliken population charge of the real-space limit calculated by QM/MM using large isolated systems. We investigated the contribution from each term of the Hamiltonian and found that the surface-dipole term in the Ewald summation technique is indispensable for QM/MM-PBC calculations. The newly developed QM/MM-PBC method is promising for tackling chemical reactions and excited states of molecules in the condensed phase.

Randomized clinical trial comparing standard diet with perioperative oral immunonutrition in total gastrectomy for gastric cancer.

BACKGROUND: Total gastrectomy for gastric cancer is associated with excessive weight loss and decreased calorie intake. Nutritional support using eicosapentaenoic acid modulates immune function and limits catabolism in patients with advanced cancer, but its impact in the perioperative period is unclear. METHODS: This was a randomized phase III clinical trial of addition of eicosapentaenoic acid-rich nutrition to a standard diet in patients having total gastrectomy for gastric cancer. Patients were randomized to either a standard diet or standard diet with oral supplementation of an eicosapentaenoic acid (ProSure®), comprising 600 kcal with 2·2 g eicosapentaenoic acid, for 7 days before and 21 days after surgery. The primary endpoint was percentage bodyweight loss at 1 and 3 months after surgery. RESULTS: Of 127 eligible patients, 126 were randomized; 124 patients (61 standard diet, 63 supplemented diet) were analysed for safety and 123 (60 standard diet, 63 supplemented diet) for efficacy. Across both groups, all but three patients underwent total gastrectomy with Roux-en-Y reconstruction. Background factors were well balanced between the groups. Median compliance with the supplement in the immunonutrition group was 100 per cent before and 54 per cent after surgery. The surgical morbidity rate was 13 per cent in patients who received a standard diet and 14 per cent among those with a supplemented diet. Median bodyweight loss at 1 month after gastrectomy was 8·7 per cent without dietary supplementation and 8·5 per cent with eicosapentaenoic acid enrichment (P = 0·818, adjusted P = 1·000). Similarly, there was no difference between groups in percentage bodyweight loss at 3 months (P = 0·529, adjusted P = 1·000). CONCLUSION: Immunonutrition based on an eicosapentaenoic acid-enriched oral diet did not reduce bodyweight loss after total gastrectomy for gastric cancer compared with a standard diet. Registration number: UMIN000006380 ( http://www.umin.ac.jp/).

Metabolic enrichment of omega-3 polyunsaturated fatty acids does not reduce the onset of idiopathic knee osteoarthritis in mice.

OBJECTIVE: We evaluated the effect of a reduction in the systemic ratio of n-6:n-3 polyunsaturated fatty acids (PUFAs) on changes in inflammation, glucose metabolism, and the idiopathic development of knee osteoarthritis (OA) in mice. We hypothesized that a lower ratio of n-6:n-3 PUFAs would protect against OA markers in cartilage and synovium, but not bone. DESIGN: Male and female fat-1 transgenic mice (Fat-1), which convert dietary n-6 to n-3 PUFAs endogenously, and their wild-type (WT) littermates were fed an n-6 PUFA enriched diet for 9-14 months. The effect of gender and genotype on serum PUFAs, interleukin (IL)-6, tumor necrosis factor (TNF)-α, and glucose tolerance was tested by 2-factor analysis of variance (ANOVA). Cortical and trabecular subchondral bone changes were documented by micro-focal computed tomography (CT), and knee OA was assessed by semi-quantitative histomorphometry grading. RESULTS: The n-6:n-3 ratio was reduced 12-fold and 7-fold in male and female Fat-1 mice, respectively, compared to WT littermates. IL-6 and TNF-α levels were reduced modestly in Fat-1 mice. However, these systemic changes did not reduce osteophyte development, synovial hyperplasia, or cartilage degeneration. Also the fat-1 transgene did not alter subchondral cortical or trabecular bone morphology or bone mineral density. CONCLUSIONS: Reducing the systemic n-6:n-3 ratio does not slow idiopathic changes in cartilage, synovium, or bone associated with early-stage knee OA in mice. The anti-inflammatory and anti-catabolic effects of n-3 PUFAs previously reported for cartilage may be more evident at later stages of disease or in post-traumatic and other inflammatory models of OA.

Antimicrobial photodynamic therapy using a diode laser with a potential new photosensitizer, indocyanine green-loaded nanospheres, may be effective for the clearance of Porphyromonas gingivalis.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a new treatment method for the removal of infectious pathogens using a photosensitizer and light of a specific wavelength, e.g., toluidine blue with a wavelength of about 600 nm. We explored a new photosensitizer and focused on indocyanine green (ICG), which has high absorption at a wavelength of 800-805 nm. We investigated the bactericidal effect of PDT on Porphyromonas gingivalis using a new photosensitizer, ICG-loaded nanospheres with an 805 nm wavelength low-level diode laser irradiation. METHODS: We designed ICG-loaded nanospheres coated with chitosan (ICG-Nano/c) as a photosensitizer. A solution containing Porphyromonas gingivalis (10(8)  CFU/mL) with or without ICG-Nano/c (or ICG) was prepared and irradiated with a diode laser or without laser irradiation as a negative control. The irradiation settings were 0.5 W with a duty ratio of 10%, for 3-100 ms in repeated pulse (RPT) or continuous wave mode. CFU were counted after 7 d of anaerobic culture. RESULTS: We observed that ICG-Nano/c could adhere to the surface of P. gingivalis. When ICG-Nano/c was used for aPDT, irradiation with RPT 100 ms mode gave the lowest increase in temperature. Laser irradiation with ICG-Nano/c significantly reduced the number of P. gingivalis (i.e., approximately 2-log10 bacterial killing). The greatest bactericidal effect was found in the RPT 100 ms group. However, laser irradiation (RPT 100 ms) with ICG, as well as without photosensitizer, had no effect on the number of bacteria. CONCLUSIONS: Within the limits of this study, ICG-Nano/c with low-level diode laser (0.5 W; 805 nm) irradiation showed an aPDT-like effect, which might be useful for a potential photodynamic periodontal therapy.

Proteomic profiling of k-11706 responsive proteins.

Erythropoietin promotes the production of red blood cells. Recombinant human erythropoietin is illicitly used to improve performance in endurance sports. Expression of the ERYTHROPOIETIN gene is negatively controlled by the transcription factor GATA-binding protein (GATA). Specific GATA inhibitors have recently been developed as novel drugs for the management of anemia. These drugs could, therefore, be illicitly used like recombinant human erythropoietin to improve performance in sports. To examine alterations in levels of plasma protein after administration of GATA inhibitors, proteomic analyses were conducted on mouse plasma samples treated with the potent GATA inhibitor K-11706. The analysis based on gel electrophoresis identified 41 protein spots differentially expressed when compared with normal plasma. Each spot was identified with liquid chromatography coupled to tandem mass spectrometry and 2 of them, fetuin-B and prothrombin, were verified by Western blotting. The results showed that the expression of fetuin-B in mice plasma was increased by K-11706, but not by recombinant human erythropoietin or hypoxia. These results suggest the potential of proteomic-based approaches as tools to identify biomarkers for the illegal use of novel drugs (e.g., GATA inhibitors). Also, fetuin-B could be a sensitive marker for the detection of abuse of GATA inhibitors.

A case of resected retroperitoneal metachronous solitary metastasis from caecal cancer.

Colorectal cancer metastasis to the retroperitoneum, especially solitary metastasis allowing curative resection, is rare. We report a case of complete resection of retroperitoneal metachronous solitary metastasis from caecal cancer without distant metastasis. An 80-year-old woman with caecal cancer underwent laparoscopic ileocaecal resection with regional lymph node dissection. According to the eighth edition of the TNM classification, the pathological diagnosis was stage IIA (T3N0M0). Six months following the surgery, computed tomography revealed a solitary mass of 2cm diameter, dorsal to the right kidney. A second procedure for the removal of the tumour was performed. The lesion was pathologically diagnosed as a metachronous solitary retroperitoneal metastasis from caecal cancer. The patient is surviving and free from recurrence 17 months following the second procedure.

Apolipoprotein E deficiency abrogates insulin resistance in a mouse model of type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Although it is known that lipid metabolism plays a role in insulin resistance in type 2 diabetes and in obesity, the mechanism is still largely unknown. Apolipoprotein E (ApoE) regulates plasma lipid levels and also plays a role in the uptake of lipids into various tissues. To investigate whether the suppression of whole-particle lipoprotein uptake into tissues affects insulin responsiveness and the diabetic condition, we examined the effect of an ApoE (also known as Apoe) gene deletion in MKR mice, a mouse model of type 2 diabetes. METHODS: ApoE ( -/- ), MKR, ApoE ( -/- )/MKR and control mice were placed on a high-fat, high-cholesterol diet for 16 weeks. Glucose tolerance, serum insulin, blood glucose, insulin tolerance, tissue triacylglycerol content and atherosclerotic lesions were assessed. RESULTS: ApoE ( -/- )/MKR and ApoE ( -/- ) mice showed significantly improved blood glucose, glucose tolerance and insulin sensitivity. Reduced triacylglycerol content in liver and reduced fat accumulation in liver and adipose tissue were found in ApoE ( -/- )/MKR and ApoE ( -/- ) mice compared with control and MKR mice. ApoE ( -/- ) and ApoE ( -/- )/MKR mice demonstrated similarly large atherosclerotic lesions, whereas MKR and control mice had small atherosclerotic lesions. CONCLUSIONS/INTERPRETATION: We demonstrated that ApoE deficiency abrogates insulin resistance in a mouse model of type 2 diabetes, suggesting that lipid accumulation in tissue is a major cause of insulin resistance in this mouse model.

Phase II study of neoadjuvant chemotherapy and extended surgery for locally advanced gastric cancer.

BACKGROUND: Locally advanced gastric cancer with extensive lymph node metastasis is usually considered unresectable and so treated by chemotherapy. This trial explored the safety and efficacy of preoperative chemotherapy followed by extended surgery in the management of locally advanced gastric adenocarcinoma. METHODS: Patients with gastric cancer with extensive lymph node metastasis received two or three 28-day cycles of induction chemotherapy with irinotecan (70 mg/m(2) on days 1 and 15) and cisplatin (80 mg/m(2) on day 1), and then underwent gastrectomy with curative intent with D2 plus para-aortic lymphadenectomy. Primary endpoints were 3-year overall survival and incidence of treatment-related death. RESULTS: The study was terminated because of three treatment-related deaths when 55 patients had been enrolled (mortality rate above 5 per cent). Two deaths were due to myelosuppression and one to postoperative complications. Clinical response and R0 resection rates were 55 and 65 per cent respectively. The pathological response rate was 15 per cent. Median overall survival was 14.6 months and the 3-year survival rate 27 per cent. CONCLUSION: This multimodal treatment of locally advanced gastric cancer provides reasonable 3-year survival compared with historical data, but at a considerable cost in terms of morbidity and mortality.

Spherical crystallization: direct spherical agglomeration of salicylic Acid crystals during crystallization.

Direct spherical agglomeration of salicylic acid crystals during crystallization is described. The needle-like salicylic acid crystals simultaneously form and agglomerate in a mixture of three partially miscible liquids, such as water, ethanol, and chloroform, with agitation. The agglomerates can be made directly into tablets because of their excellent flowability. Spherical crystallization could eliminate the usual separate agglomeration step after crystallization and may be adaptable to other pharmaceutical and chemical systems.

Investigation of drug loading and in vitro release mechanisms of insulin-lauryl sulfate complex loaded PLGA nanoparticles.

Insulin, a water soluble peptide hormone, was hydrophobically ion-paired with sodium lauryl sulfate (SDS) at the stoichiometric molar ratio of 6:1. The obtained insulin-SDS complex precipitation was subsequently formulated in biodegradable poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles by a modified spontaneous emulsion solvent diffusion method. Compared with a conventional method for free insulin encapsulation, direct dissolution of SDS-paired insulin in the non-aqueous organic phase led to an increase in drug recovery from 42.5% to 89.6%. The more hydrophobic complex contributes to the improved affinity of insulin to the polymer matrix, resulting in a higher drug content in the nanoparticles. The drug loading was investigated by determining initial burst release at the first 30 min. The results showed that 64.8% of recovered drug were preferentially surface bound on complex loaded nanoparticles. The in vitro drug release was characterized by an initial burst and subsequent delayed release in dissolution media of deionized water and phosphate buffer saline (PBS). Compared with that in PBS, nanoparticles in deionized water medium presented very low initial burst release (15% vs. 65%) and incomplete cumulative release (25% vs. 90%) of the drug. In addition, dialysis experiments were performed to clarify the form of the released insulin in the dissolution media. The results suggested that the ion-pair complex was sensitive to ionic strength, insulin was released from the particular matrix as complex form and subsequently suffered dissociation from SDS in buffer saline. Moreover, the in vivo bioactivity of the SDS-paired insulin and nanoparticulate formulations were evaluated in mice by estimation of their blood sugar levels. The results showed that the bioactivity of insulin was unaltered after the ion-pairing process.

Optimized preparation of insulin-lauryl sulfate complex loaded poly (lactide-co-glycolide) nanoparticles using response surface methodology.

Insulin-lauryl sulfate (INS-SDS) complex loaded poly (lactic acid-co-glycolic acid) (PLGA) nanoparticles were prepared by spontaneous emulsion solvent diffusion method. To improve the insulin entrapment efficiency (E.E), a five-level-two-factor central composite design and surface response methodology (RSM) was used to determine the optimum levels of PLGA/INS complex weight ratio and PVA/ acetone volume ratio, two important variables during nanoparticles fabrication. A quadratic model to express the E.E as a function of the two studied factors was developed. Only 10 experimental runs were necessary and the obtained model was adequate (P < 0.05). By partial derivative resolution of regression model, the optimum weight ratio of PLGA/INS complex and volume ratio of PVA/acetone was determined as 25/1 and 10/1, respectively. This preparing condition resulted E.E of insulin as high as 91% during nanoparticles production. Validation of the model was accomplished by experiments carried out on optimized formulation conditions. The experimental results were in good agreement with those predicted by the model. The results indicated that RSM represents an effective and potential technique for formulation optimization.

Prospective comparison of the effects of maxacalcitol and calcitriol in chronic hemodialysis patients with secondary hyperparathyroidism: a multicenter, randomized crossover study.

BACKGROUND: Maxacalcitol is a vitamin D analogue, which is administered intravenously for secondary hyperparathyroidism in dialysis patients as well as calcitriol. However, few dose-comparison clinical studies have been reported for these drugs. The present multicenter, randomized crossover study was conducted to determine the equivalence of maxacalcitol and calcitriol doses. METHODS: Subjects comprised 31 patients on chronic hemodialysis with secondary hyperparathyroidism who had not received maxacalcitol or calcitriol in the previous 3 months. Patients were randomly divided into two groups, and maxacalcitol or calcitriol was administered in a crossover design for 12 weeks each. Maxacalcitol and calcitriol doses were adjusted based on serum levels of calcium and intact parathyroid hormone. RESULTS: After the 12-week maxacalcitol/calcitriol administration, there were no significant differences in levels of calcium (maxacalcitol 2.40+/-0.22 mmol/1 (9.6+/-0.9 mg/dl), calcitriol 2.42 + 0.25 mmol/l (9.7+/-1.0 mg/dl), p = 0.71), phosphate (maxacalcitol 1.97 + 0.42 mmol/l (6.1+/-1.3 mg/dl), calcitriol 2.00+/-0.48 mmol/l (6.2+/-1.5 mg/dl), p = 0.64), intact parathyroid hormone (maxacalcitol 267+/-169 pg/ml, calcitriol 343+/-195 pg/ml, p = 0.11) in serum or other bone-metabolic parameters such as serum alkaline phosphatase. The doses ofmaxacalcitol and calcitriol were 49.3+/-23.7 microg/month and 9.0+/-3.8 microg/month, respectively, and maxacalcitol : calcitriol dose ratio was 5.5: 1. No severe adverse reactions were seen for either maxacalcitol or calcitriol during the study period. CONCLUSIONS: Comparable therapeutic efficacy can be obtained in the treatment of secondary hyperparathyroidism using either maxacalcitol or calcitriol at a dose ratio of 5.5 : 1.

Characterisation of salmon calcitonin in spray-dried powder for inhalation. Effect of chitosan.

Salmon calcitonin (sCT) powders suitable for inhalation, containing chitosan and mannitol as absorption enhancer and protection agent, respectively, were prepared using a spray-drying process. The effect of chitosan on physicochemical stability of sCT in the dry powder was investigated by different analytical techniques. High-performance liquid chromatography (HPLC) analysis indicated that sCT was chemically stable upon spray-drying. With the proportion of chitosan in spray-drying formulation being increased, dissolution of sCT from the dry powders was decreased both in phosphate buffer and acetate buffer. The thioflavine T fluorescence assay showed that no fibrils were present in the spray-dried powder. However, sCT partly fibrillated in the phosphate buffer, but not in acetate buffer. Fourier transform infrared (FTIR) spectra showed that the secondary structure of sCT was slightly changed in the dry powder, yet no aggregate signal was observed. Circular dichroism analysis indicated that the structure of sCT in an aqueous formulation was slightly altered by addition of chitosan. Nevertheless, recovery of sCT was not influenced by chitosan in the aqueous formulation as indicated by HPLC analysis. This study suggested that sCT, in absence of any additives, was stable during the spray-drying process under certain conditions. Addition of chitosan affects recovery of sCT from spray-dried powders, which may be due to formation of a partially irreversible complex between the protein and chitosan during the spray-drying process.

Non-destructive elemental analysis of a carbonaceous chondrite with direct current Muon beam at MuSIC.

Electron- or X-ray-induced characteristic X-ray analysis has been widely used to determine chemical compositions of materials in vast research fields. In recent years, analysis of characteristic X-rays from muonic atoms, in which a muon is captured, has attracted attention because both a muon beam and a muon-induced characteristic X-ray have high transmission abilities. Here we report the first non-destructive elemental analysis of a carbonaceous chondrite using one of the world-leading intense direct current muon beam source (MuSIC; MUon Science Innovative Channel). We successfully detected characteristic muonic X-rays of Mg, Si, Fe, O, S and C from Jbilet Winselwan CM chondrite, of which carbon content is about 2 wt%, and the obtained elemental abundance pattern was consistent with that of CM chondrites. Because of its high sensitivity to carbon, non-destructive elemental analysis with a muon beam can be a novel powerful tool to characterize future retuned samples from carbonaceous asteroids.

Properties of liposomes coated with hydrophobically modified chitosan in oral liposomal drug delivery.

Chitosan (CS) has been widely used as an adhesive coating polymer for oral liposomal drug delivery systems because of its adhesive properties on mucous layers. The coating mechanism or interaction of chitosan and liposomes or mucin mainly depends on electrostatic forces. Thus, to enhance the adhesive properties of chitosan, a hydrophobically modified chitosan, i.e., dodecylated chitosan (DC), was synthesized. BIACORE results showed that both CS and DC could interact with mucin. Differences in sensorgram patterns between chitosan-mucin and dodecylated chitosan-mucin were observed and tentatively attributed to differences in binding kinetics. The zeta potential of dodecylated chitosan-coated liposomes (DC-Lip) showed positive values in both liposomal formulations, i.e., negatively charged and neutral-charge liposomes. These results indicated that DC could be considered a more suitable polymer for coating neutral-charge liposomes than CS because the hydrophobic side chain of DC inserts itself into the lipid bilayer of liposomes. Moreover, CS seemed to be less effective in the coating of a neutral-charge liposome because of the low positive values of its zeta potential. CS provided solely electrostatic forces when used for coating liposomes while DC provided electrostatic and hydrophobic forces due to the long alkyl chain in its backbone. Confocal Laser Scanning Microscopy (CLSM) images indicated that both chitosan-coated liposomes (CS-Lip) and DC-Lip could adhere to and penetrate through the small intestine of rats after oral administration. The pharmacological results showed that DC-Lip had a greater effect in decreasing blood calcium concentration during the first 12 h compared with CS-Lip. Therefore, it can be concluded that dodecylated chitosan can be useful in designing oral liposomal drug delivery systems.

Cell injury by antineoplastic agents and influence of coenzyme Q10 on cellular potassium activity and potential difference across the membrane in rat liver cells.

Potential difference across the cell membrane and intracellular activity of the potassium ion in rat liver cells were measured simultaneously using double-barreled potassium ion-selective microelectrodes. Both potential difference across the membrane and K+ activity in liver cells were depressed after treatment with the antineoplastic agents mitomycin C and 5-Flourouracil Dry Syrup, suggesting that these drugs would induce disturbances of cellular energy metabolism in liver cells. When the antineoplastic agents were used in combination with coenzyme Q10, the depression of potential difference across the membrane and K+ activity and the hypofunction of liver cells in energy metabolism were significantly prevented.

Regulation of palmitoyl-CoA chain elongation and linoleoyl-CoA chain elongation in rat liver microsomes and the differential effects of peroxisome proliferators, insulin and thyroid hormone.

Treatment of rats with p-chlorophenoxyisobutyric acid (clofibric acid), 2,2'-(decamethylenedithio)diethanol, di(2-ethylhexyl)phthalate or acetylsalicylic acid caused an increase in activity of palmitoyl-CoA chain elongation in hepatic microsomes. The activity of palmitoyl-CoA chain elongation decreased in both hypothyroid-state and diabetic-state rats, increased in hyperthyroid-state rats and did not change in adrenalectomized rats. The administration of clofibric acid to these rats in an altered hormonal state caused an increase in the activity of palmitoyl-CoA chain elongation, but no additional increase in the activity was observed with treatment of hyperthyroid rats with clofibric acid. The activity of linoleoyl-CoA chain elongation did not respond to the changes in either the nutritional conditions or the hormonal state of insulin so sensitively as the activity of palmitoyl-CoA chain elongation. The treatment of rats with triiodothyronine caused a marked increase in the activity of linoleoyl-CoA chain elongation; nevertheless, the activity of linoleoyl-CoA chain elongation was not changed by the treatment of rats with clofibric acid. The results suggest that rat liver microsomes contain at least two fatty acid chain elongation systems and that these chain elongation systems are regulated differently by hormones and drugs.

Role of phosphatidylcholine on microsomal chain elongation and the fate of stearoyl-CoA in rat liver microsomes.

The effect of phosphatidylcholine dispersion on the chain elongation of palmitoyl-CoA in rat liver microsomes has been investigated. Addition of phosphatidylcholine increased the formation of stearic acid and its incorporation into phosphatidylcholine. In the presence or absence of phosphatidylcholine, newly-formed stearic acid was preferentially incorporated into the C-1 position of phosphatidylcholine. The incorporation of newly formed stearic acid into microsomes was much higher than that into the added phosphatidylcholine dispersion.