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In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO

Chlorophyll (Chl) and effective photoprotective mechanism are important prerequisites to ensure the photosynthetic function of plants under stress. In this study, the effects of 100 mmol L−1 NaCl and NaHCO3 stress on chlorophyll synthesis and photosynthetic function of mulberry seedlings were studied by physiological combined with proteomics technology. The results show that: NaCl stress had little effect on the expression of Chl synthesis related proteins, and there were no significant changes in Chl content and Chl a:b ratio. However, 13 of the 15 key proteins in the process of Chl synthesis were significantly decreased under NaHCO3 stress, and the contents of Chl a and Chl b were significantly decreased (especially Chl a). Although stomatal conductance (Gs) decreased significantly under NaCl stress, net photosynthetic rate (Pn), PSII maximum photochemical efficiency (Fv/Fm) and electron transfer rate (ETR) did not change significantly, but under NaHCO3 stress, not only Gs decreased significantly, PSII activity and photosynthetic carbon were the same. In the photoprotective mechanism under NaCl stress, NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow (CEF) enhanced, the expression of related proteins subunit, ndhH, ndhI, ndhK, and ndhM, the key enzyme of the xanthophyll cycle, violaxanthin de-epoxidase (VDE) were up-regulated, the ratio of (A + Z)/(V + A + Z) and non-photochemical quenching (NPQ) was increased. The expressions of proteins FTR and Fd-NiR were also significant up-regulated under NaCl stress, Fd-dependent ROS metabolism and nitrogen metabolism can effectively reduce the electronic pressure on Fd. Under NaHCO3 stress, the expressions of NDH-dependent CEF related proteins subunit (ndhH, ndhI, ndhK, ndhM and ndhN), VDE, ZE, FTR, Fd-NiR and Fd-GOGAT, were significant down-regulated, and ZE, CP26, ndhK, ndhM, Fd-NiR, Fd-GOGAT and FTR genes expression also significantly decreased, the photoprotective mechanism, like the xanthophyll cycle，CEF and Fd-dependent ROS metabolism and nitrogen metabolism might be damaged, resulting in the inhibition of PSII electron transfer and carbon assimilation in mulberry leaves under NaHCO3 stress.

AIMS: The aims of the present study were to characterize the pharmacokinetics of voriconazole in renal transplant recipients and to identify factors significantly affecting pharmacokinetic parameters. We also aimed to explore the optimal dosing regimens for patients who developed invasive fungal infections. METHODS: A total of 105 patients (342 concentrations) were included prospectively in a population pharmacokinetic analysis. Nonlinear mixed‐effects models were developed using Phoenix NLME software. Dosing simulations were performed based on the final model. RESULTS: A one‐compartment model with first‐order absorption and elimination was used to characterize voriconazole pharmacokinetics. Population estimates of clearance, volume of distribution and oral bioavailability were 2.88 l·h(−1), 169.3 l and 58%, respectively. The allele frequencies of cytochrome P450 gene (CYP) 2C19*2, *3 and *17 variants were 29.2%, 5.2% and 0.5%, respectively. CYP2C19 genotype had a significant effect on the clearance. Voriconazole trough concentrations in poor metabolizers were significantly higher than in intermediate metabolizers and extensive metabolizers alike. The volume of distribution increased with increased body weight. The oral bioavailability was substantially lower within 1 month after transplantation but increased with postoperative time. Dosing simulations indicated that during the early postoperative period, poor metabolizers could be treated with 150 mg intravenously or 250 mg orally twice daily; intermediate metabolizers with 200 mg intravenously or 350 mg orally twice daily; and extensive metabolizers with 300 mg intravenously twice daily. CONCLUSIONS: Using a combination of CYP2C19 genotype and postoperative time to determine the initial voriconazole dosing regimens followed by therapeutic drug monitoring could help to advance individualized treatment in renal transplantation patients with invasive fungal infections.

In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO3 stress were studied by using chlorophyll fluorescence and gas exchange technique combined with TMT proteomics. The results showed that NaCl stress had no significant effect on photosystem II (PSII) activity in M. alba seedling leaves. In addition, the expressions of proteins of the PSII oxygen-evolving complex (OEE3-1 and PPD4) and the LHCII antenna (CP24 10A, CP26, and CP29) were increased, and the photosystem I (PSI) activity in the leaves of M. alba seedlings was increased, as well as expressions of proteins, such as PsaF, PsaG, PsaH, PsaL, PsaN, and Ycf4. Under NaHCO3 stress, the activity of PSII and PSI and the expression of their protein complexes and the electron transfer-related proteins significantly decreased. NaCl stress had little effect on RuBP regeneration during dark reaction in the leaves and the expressions of glucose synthesis related proteins and net photosynthetic rate (Pn) did not decrease significantly. The leaves could adapt to NaCl stress by reducing stomatal conductance (Gs) and increasing water use efficiency (WUE). Under NaHCO3 stress, the expression of dark reaction-related proteins was mostly down-regulated, while Gs was reduced, which indicated that non-stomatal factors can be responsible for inhibition of carbon assimilation.

To investigate the effects of sonicated extracts of Porphyromonas gingivalis (Pg) on osteogenic differentiation of mouse osteoblast cell line MC3T3-E1.PgW83 was cultured under standard anaerobic conditions and extracted by sonication. Mouse osteoblast cell line MC3T3-E1 was cultured with various concentrations of the extraction (0, 10, 100, 1000 mg/L). Western blotting was applied to investigate the expression of osteocalcin (OC), bone sialoprotein (BSP), osteopontin (OPN) and osteonectin (ON). The activity of alkaline phosphatase (ALP) was detected by microplate reader after 14 days. Mineralization nodule formation was measured by alizarin red staining after 21 days.Compared with the control group, the extracts of Pg decreased OC and ON expression in a dose-dependent manner (OC relative expression:1.000 ± 0.000,0.852 ± 0.110,0.625 ± 0.451,0.213 ± 0.053), (ON relative expression: 1.000 ± 0.000, 1.035 ± 0.133,0.141 ± 0.023,0.020 ± 0.003) (P0.05). The expression of OPN was down-regulated significantly in MC3T3-E1 treated with 1000 mg/L extraction (0.572 ± 0.162) compared with control group, 10 and 100 mg/L (1.000 ± 0.000, 1.029 ± 0.135, 1.199 ± 0.337) (P0.05). The expression of BSP remained unchanged when the cells were cultured with or without extraction (BSP relative expression:1.000 ± 0.000,0.831 ± 0.182,0.897 ± 0.115,0.778 ± 0.235) (P0.05). Meanwhile, the extracts of Pg decreased ALP activity [control group:(0.0275 ± 0.0014) U/gprot, 10 mg/L: (0.0140 ± 0.0011) U/gprot, 100 mg/L: (0.0057 ± 0.0013) U/gprot, 1000 mg/L: (0.0020 ± 0.0008) U/gprot] (P0.05) and reduced mineralization nodule formation.The results suggest that Pg may inhibit osteoblasts'osteogenic function by down-regulation of osteogenic differentiation related proteins.

The Porphyromonas gingivalis bacterium is one of the most influential pathogens in oral infections. In the current study, the antimicrobial activity of α-amylase and pentamidine against Porphyromonas gingivalis was evaluated. Their in vitro inhibitory activity was investigated with the agar overlay technique, and the minimal inhibitory and bactericidal concentrations were determined. Using the bactericidal concentration, the antimicrobial actions of the inhibitors were investigated. In the present study, multiple techniques were utilized, including scanning electron microscopy (SEM), general structural analysis and differential gene expression analysis. The results obtained from SEM and bactericidal analysis indicated a notable observation; the pentamidine and α-amylase treatment destroyed the structure of the bacterial cell membranes, which led to cell death. These results were used to further explore these inhibitors and the mechanisms by which they act. Downregulated expression levels were observed for a number of genes coding for hemagglutinins and gingipains, and various genes involved in hemin uptake, chromosome replication and energy production. However, the expression levels of genes associated with iron storage and oxidative stress were upregulated by α-amylase and pentamidine. A greater effect was noted in response to pentamidine treatment. The results of the present study demonstrate promising therapeutic potential for α-amylases and pentamidine. These molecules have the potential to be used to develop novel drugs and broaden the availability of pharmacological tools for the attenuation of oral infections caused by Porphyromonas gingivalis.

To investigate the effect of synthesized advanced glycation end products (AGE) on apoptosis of human gingival fibroblasts (HGF) and the possible role of caspase-dependent pathway in the process of AGE-induced apoptosis.HGF were incubated with AGE-human serum albumin (AGE-HSA). The activity of caspase-8, caspase-9 and caspase-3 were detected by microplate reader after 12 and 24 hours. HGF were incubated with caspase inhibitors for 1 hour, and then incubated with AGE-HSA for 24 hours, HGF was first stained by Hoechst33258 and observed under inverted microscope, and then double stained by annexin V and propidine iodide (PI) and observed by flow cytometry (FCM). The activity of caspase-3 was determined by caspase-3 assay kit and observed by microplate reader.Caspases activity of caspase-8, -9, -3 was 0.1097 ± 0.0051, 0.0965 ± 0.0051 and 0.1280 ± 0.0103 after 12 h of incubation with AGE-HSA and HGF, respectively, and 0.1558 ± 0.0053, 0.1308 ± 0.0035 and 0.1954 ± 0.0051 after 24 h of incubation with AGE-HSA and HGF, respectively (P0.05). Positive cells number was 247.7 ± 32.4, 200.1 ± 14.6, 154.1 ± 14.4 and 131.3 ± 14.6 in caspase inhibitor groups by Hoechst33258 staining, respectively. Apoptotic rate was (25.57 ± 2.20)%, (38.87 ± 3.31)%, (17.17 ± 2.24)% and (14.73 ± 2.48)% in caspase inhibitor groups by annexin V-PI staining, respectively. The difference between different groups was significant (P0.05). Caspase-3 activity was reduced to 0.1274 ± 0.0076, 0.1465 ± 0.0062, 0.1044 ± 0.0051 in caspase inhibitor groups, respectively. The difference between different groups was significant (P0.05).Apoptosis of HGF induced by AGE-HSA may be mainly through activation of caspase-dependant pathway in which cytoplasmic pathway may play a predominant role.

Although the effectiveness of fluoride dentifrice in remineralizing enamel caries has been established, the optimum fluoride concentration for remineralization root caries has not been defined. The aim of this study was to assess and compare the effect of 1.1g/L, 1.45g/L and 5g/L fluoride dentifrices in remineralization of artificial root caries.Sound human tooth fragments obtained from the cervical portion of root were stored in a demineralization solution for 96h at 37 degrees centigrade to induce artificial root caries lesions. The fragments were then randomly divided into four treatment groups including 1.1g/L, 1.45g/L, 5g/L fluoride dentifrice group and non-fluoride dentifrice control group. The demineralized samples were pH-cycled through treatment solutions, acidic buffer and neutral buffer for 8 days at 6 cycles per day. The samples were evaluated using electrical caries monitor(ECM), polarized light microscopy (PLM) and confocal laser scanning microscopy (CLSM). The data was analyzed using ANOVA with SPSS13.0 software package.Variations of LgECM, total fluorescence and average fluorescence from CLSM after remineralization in fluoride dentifrice groups were significantly higher than those in the control group(P0.05) Variations of LgECM, total fluorescence and average fluorescence from CLSM after remineralization in the 5g/L fluoride dentifrice group were significantly higher than those in the 1.1g/L and 1.45g/L fluoride dentifrice groups(P0.05). PLM observation showed that a banding or deposit of mineral appeared within the lesions of specimens in the fluoride dentifrice groups. A wider mineral band was seen in the 5g/L fluoride dentifrice group than in the 1.1g/L and 1.45g/L fluoride dentifrice groups.Fluoride dentifrice is effective in remineralizing artificial root caries and 5g/L fluoride dentifrice has better effect than 1.1g/L and 1.45g/L fluoride dentifrices.

We investigate the kinetics of a nonrelativistic particle interacting with a constant external force on a Lie-algebraic noncommutative space. The structure constants of a Lie algebra, also called noncommutative parameters, are constrained in general due to some algebraic properties, such as the antisymmetry and Jacobi identity. Through solving the constraint equations the structure constants satisfy, we obtain two new sorts of algebraic structures, each of which corresponds to one type of noncommutative spaces. Based on such types of noncommutative spaces as the starting point, we analyze the classical motion of the particle interacting with a constant external force by means of the Hamiltonian formalism on a Poisson manifold. Our results {\em not only} include that of a recent work as our special cases, {\em but also} provide new trajectories of motion governed mainly by marvelous extra forces. The extra forces with the unimaginable $t\dot{x}$-, $\dot{(xx)}$-, and $\ddot{(xx)}$-dependence besides with the usual $t$-, $x$-, and $\dot{x}$-dependence, originating from a variety of noncommutativity between different spatial coordinates and between spatial coordinates and momenta as well, deform greatly the particle's ordinary trajectories we are quite familiar with on the Euclidean (commutative) space., 21 pages, 4 figures; v2: minor clarification and two references added; v3: 22 pages, clarifications added; v4: 23 pages, clarifications added; v5: minor layout revision, final version accepted by Annals of Physics

To evaluate the long-term clinical effects of orthotopic ileal or sigmoidocolic neobladder.One hundred and twenty six patients with bladder cancer who underwent radical cystectomy and orthotopic ileal or sigmoidocolic neobladder from 1989 to 2001 were followed up, the clinical data was collected and analysed. Hautmann orthotopic ileal neobladder was performed on 84 cases and orthotopic sigmoidocolic neobladder was performed on 42 cases; Lymph node clearing during surgery was performed on 62 cases, chemotherapy and radiotherapy was performed on 64 cases after surgery. The continence and complications were compared between sigmoidocolic group and ileal group, the tumor recurrent rate and the 5-year survival rate were compared between lymphnode clearing group and chemoradical therapy group.Complete follow up was performed in 122 cases. Ureter broaden and urine backflow rate were higher in sigmoidocolic group than in ileal group (P0.05), nocturnal continence rate in sigmoidocolic group was higher than in ileal group (P0.05); Post-surgical tumor recurrent rate in lymphnode clearing group was lower than in chemoradical therapy group (P0.05), the 5-year survival rate in lymphnode clearing group was higher than in chemoradical therapy group (P0.05). The overall short-term complication rate was 15.9% (20/126), the overall long-term complication rate was 9.8% (12/122).The effects of orthotopic ileal or sigmoidocolic neobladder were satisfactory with low complication rate, lymphnode clearing during the surgery can increase the 5-year survival rate when compared with the chemoradical group.

To investigate the influence of a broad range of environmental conditions on initial rates of hydrogen peroxide produced by Streptococcus oralis (S. oralis).For each rate measurement, 1 ml aliquots of 10(12) cells/L mid-logarithmic phase S. oralis in TSBY were centrifuged and respectively washed by phosphate buffer containing 0.01-10 mmol/L glucose or sucrose, phosphate buffer with 5.0-7.5 pH or Bis-Tris buffer containing 0.01-100 mmol/L Ca(2+), 0.01-100 mmol/L F(-) or 0.01-100 mmol/L HFPO(3)(-). After S. oralis was cultured in respective buffer for 10, 20 and 30 min at 37 degrees C, the concentration of hydrogen peroxide in supernatant was assayed spectrophotometrically in 96-well micro-plate by ABTS-HRP at A(405).Synthesis rate of hydrogen peroxide by S. oralis was 7.48 micromol/L per minute without carbohydrate, the synthesis rate of hydrogen peroxide by S. oralis increased with 0.01-10 mmol/L glucose and 0.01-10 mmol/L sucrose, but there was no statistically significant difference in synthesis rate among the carbohydrate groups. The rates of H2O2 synthesis were inhibited in the buffer at pH 5.0-6.0, compared with pH 7.0 (P0.05). Ca(2+) had little influence on the rate of H2O2 synthesis. IC(50) of H2O2 synthesis rates by S. oralis responded to FHPO(3)(-) and F(-) were 12.65 mmol/L and 1.90 mmol/L respectively.Environmental conditions may influence the synthesis rate of H2O2 by S. oralis.