[Focal segmental glomerulosclerosis after renal transplantation in a child with ANCA-associated glomerulonephritis: case report and literature review]

Objective: To study the clinical features and treatment of focal segmental glomerulosclerosis (FSGS) after renal transplantation in a child with ANCA-associated glomerulonephritis. Method: The clinical and pathological data of the patient treated in the Department of Pediatrics as well as in the Department of Organ Transplantation in November 2015 in the First Affiliated Hospital of Sun Yat-sen University, who was diagnosed with de novo FSGS after renal transplantation with a primary disease ANCA-associated glomerulonephritis, was analyzed retrospectively. Reports on "ANCA-associated glomerulonephritis" "(renal OR kidney) transplantation" "focal segmental glomerular sclerosis" were searched and reviewed. Result: A ten years old female was definitely diagnosed with ANCA-associated glomerulonephritis on the 81^st day after the onset of primary ANCA associated glomerulonephritis. Because of progressive decline of renal function, a hemodialysis period for 7 months was administered following the pulsed methylprednisolone as well as cyclophosphamide treatment. The renal transplantation was then carried out 18 months later, the renal function recovered 7 days later while proteinuria reappeared 28 days after renal transplantation. Based on the anti-rejection treatment, 3 times pulsed methylprednisolone administration did not make difference on reducing the proteinuria and then a renal biopsy was conducted and the transplanted kidney proved to be a newly developed FSGS. Consequently, plasma exchange therapy was administrated. When the plasma exchange course finished, the proteinuria decreased significantly (from 3.270 g/24 h to 0.370 g/24 h). No reports were retrieved either in Chinese databases or at PubMed as well as Medline databases. Conclusion: FSGS appears in transplanted kidney in patient with a primary renal disease as ANCA associated glomerulonephritis with early proteinuria after transplantation as well as negative P-ANCA and MPO. Pathology of renal biopsy revealed FSGS while the pathology of other recipient was not FSGS. The patient had no response to pulsed methylprednisolone therapy. Instead, plasma exchange therapy was an alternative also effective treatment for de novo FSGS in transplanted kidney.

Decreased epithelial and plasma miR-181b-5p expression associates with airway eosinophilic inflammation in asthma

BACKGROUND

Airway eosinophilic inflammation is a pivotal feature of asthma. Epithelial cells play critical roles in airway eosinophilia. We hypothesized that epithelial microRNAs (miRNAs) are involved in airway eosinophilia.

OBJECTIVE

This study investigated the associations between epithelial and plasma miR-181b-5p and airway eosinophilic inflammation, and the possible mechanism by which miR-181b-5p participates in eosinophilic inflammation.

METHODS

Epithelial miRNAs expression was profiled by miRNA array in eight subjects with asthma and four healthy controls. Epithelial miR-181b-5p expression was confirmed by quantitative PCR in the subjects for array experiment and another cohort including 21 subjects with asthma and 10 controls. Plasma miR-181b-5p was determined by quantitative PCR in 72 subjects with asthma and 35 controls. Correlation assays between epithelial and plasma miR-181b-5p expression and airway eosinophilia were performed. The target of miR-181b-5p, SPP1, was predicted by online algorithms and verified in BEAS-2B cells. The role of miR-181b-5p in epithelial proinflammatory cytokine expression was examined in an in vitro system.

RESULTS

Epithelial miR-181b-5p expression was decreased in subjects with asthma. Epithelial miR-181b-5p levels were inversely correlated with sputum and bronchial submucosal eosinophilia. Plasma miR-181b-5p was decreased and correlated with epithelial miR-181b-5p in subjects with asthma. There was a strong inverse correlation between plasma miR-181b-5p and airway eosinophilia in subjects with asthma. Plasma miR-181b-5p was increased after inhaled corticosteroids treatment. We verified that SPP1 is a target of miR-181b-5p. In human bronchial epithelial cells, miR-181b-5p regulated IL-13-induced IL-1β and CCL11 expression by targeting SPP1. Dexamethasone restored IL-13-induced miR-181b-5p down-regulation and suppressed IL-13-induced SPP1, IL-1β and CCL11 expression.

CONCLUSIONS AND CLINICAL RELEVANCE

Epithelial and plasma miR-181b-5p are potential biomarkers for airway eosinophilia in asthma. MiR-181b-5p may participate in eosinophilic airway inflammation by regulating proinflammatory cytokines expression via targeting SPP1.

Lymphoepithelial carcinoma of the salivary gland: morphologic patterns and imaging features on CT and MRI

BACKGROUND AND PURPOSE

Lymphoepithelial carcinoma is a rare salivary gland lesion. We retrospectively reviewed CT and MR imaging features of salivary gland lymphoepithelial carcinoma to determine their imaging features and morphologic patterns.

MATERIALS AND METHODS

The clinical data, CT, and MR imaging findings of 28 patients with histologically proved lymphoepithelial carcinoma of the salivary gland were retrospectively reviewed. Morphologic patterns of the lesions were categorized into 3 types on the basis of margin and shape.

RESULTS

There were 17 men and 11 women with a mean age of 39.3 years; 96.4% of patients were positive for Epstein-Barr virus both on histologic staining and Epstein-Barr virus serology. Tumors were parotid in 18 patients, submandibular in 8 patients, sublingual in 1 patient, and palatal in 1 patient. Most tumors (57.1%) manifested as a partially or ill-defined mass with a lobulated or plaque-like shape. Homogeneous enhancement was found in 16 patients, while heterogeneous enhancement was found in 12, including 4 patients with intratumoral necrosis. Invasion into adjacent structures was found in 5 patients; 60.7% of patients exhibited abnormal lymph nodes, with nodal necrosis in 3 patients.

CONCLUSIONS

The characteristic lobulated or plaque-like shape, with a partially or ill-defined margin, of a salivary gland mass associated with ipsilateral lymphadenopathy may suggest a preoperative diagnosis of lymphoepithelial carcinoma.

Enhanced styrene recovery from waste polystyrene pyrolysis using response surface methodology coupled with Box-Behnken design

A work applied response surface methodology coupled with Box-Behnken design (RSM-BBD) has been developed to enhance styrene recovery from waste polystyrene (WPS) through pyrolysis. The relationship between styrene yield and three selected operating parameters (i.e., temperature, heating rate, and carrier gas flow rate) was investigated. A second order polynomial equation was successfully built to describe the process and predict styrene yield under the study conditions. The factors identified as statistically significant to styrene production were: temperature, with a quadratic effect; heating rate, with a linear effect; carrier gas flow rate, with a quadratic effect; interaction between temperature and carrier gas flow rate; and interaction between heating rate and carrier gas flow rate. The optimum conditions for the current system were determined to be at a temperature range of 470-505°C, a heating rate of 40°C/min, and a carrier gas flow rate range of 115-140mL/min. Under such conditions, 64.52% WPS was recovered as styrene, which was 12% more than the highest reported yield for reactors of similar size. It is concluded that RSM-BBD is an effective approach for yield optimization of styrene recovery from WPS pyrolysis.

Temporal and spatial expression of podocyte-associated molecules are accompanied by proteinuria in IgA nephropathy rat model

We used a rat model to assess the role of nephrin, podocin, and desmin in the pathogenesis of IgA nephropathy (IgAN). A rat IgAN model was established by administration of BSA, CCl(4), and lipopolysaccharide (LPS) and compared with healthy control rats. Urinary protein, urine red blood cells, and biochemical parameters were measured for 12 weeks. Renal morphology and ultrastructure were examined by light and electron microscopy. Immunofluorescence was used to assess IgA deposition in the glomeruli and to measure expression of nephrin, podocin, and desmin. Real-time quantitative PCR was used to measure expression of nephrin, podocin, and desmin mRNAs. IgAN rats developed proteinuria at week-6 and this worsened over time. Pathological changes were evident under light microscopy at week-8 and under electron microscopy at week-4. Immunofluorescence analysis showed deposition of IgA in the kidneys of IgAN rats, but not control rats. IgAN rats had increased expression of glomerular podocin, nephrin, and desmin mRNAs and proteins at week-4. The expression of nephrin, podocin and desmin proteins and the expression of podocin and desmin mRNAs preceded the increase in urinary protein. Taken together, our study of a rat model of IgAN indicates that changes in the expression and distribution of nephrin, podocin, and desmin precede and may cause foot process fusion and proteinuria.

Effects of residual gas exposure on the field emission properties of ZnO nanorods

We compare the effects of O2, CO2, N2, H2, and Ar residual gas exposure on the field emission (FE) properties of ZnO nanorods. In contrast to carbon nanotubes and Mo metal microtips, we find that O2 and CO2 exposures do not significantly degrade the FE properties of ZnO nanorods. However, N2 exposure significantly degrades the FE properties. We propose that this could be due to the dissociation of N2 into atomic nitrogen species and the reaction of such species with ZnO. H2 and Ar exposures are not observed to significantly degrade the FE properties.

[Biosorption of Cd(II), Cu(II), Pb(II) and Zn(II) in aqueous solutions by fruiting bodies of macrofungi (Auricularia polytricha and Tremella fuciformis)]

Batch experiments were conducted to study the ability of fruiting bodies of Auricularia polytricha and Tremella fuciformis to adsorb Cd(II), Cu(II), Pb(II) and Zn(II) from aqueous solutions, including biosorption ability of the biomass to remove heavy metals from solutions with different concentrations, kinetics of adsorption, influence of co-cations, and biosorption affinity in multi-metalsystem. Results showed that in the solutions with individual metal, the maximum biosorption amounts of Cd(II), Cu(II), Pb(II), Zn(II) by A. polytricha were 18.91, 18.69, 20.33, 12.42 mg x g(-1), respectively, and the highest removal rates for all cases were more than 85%. The maximum biosorption amounts of Cd(II), Cu(II), Pb(II), Zn(II) by T. fuciformis were 19.98, 20.15, 19.16, 16.41 mg x g(-1), respectively, and highest removal rates for all cases were more than 75%. In the solutions with initial concentrations of 10, 50 and 100 mg x L(-1), the biosorption amounts increased but the removal rates decreased as the initial concentrations increasing. The pseudo-second-order reaction model described adsorption kinetics of heavy metal ions by fruiting bodies of A. polytricha and T. fuciformis better than the pseudo-first-order reaction model. In the solutions with multi metals, the biosorption amounts of heavy metals by two biosorbent were in the order of Ph(II) > Cd(II) > Cu(II) > Zn(II). The ions with more negative charges were preferential to be sorbed. The biosorption ability of A. polytricha was inhibited in multi-metal solutions. In multi-metal solutions, T. fuciformis sorbed a higher amount of Pb(II) but lower amounts of other three ions than that in the individual metal solutions. The results indicated that both fruiting bodies of A. polytricha and T. fuciformis were potential biosorbents.

[Analysis of articles published in Chinese Journal of Burns winning high citation rate during 2000-2009]

OBJECTIVE

To analyze the inherent quality of articles published in our journal enjoying high citation rate, and to explore strategies on improving impact of papers.

METHODS

Scientific papers published in Chinese Journal of Burns from February 2000 to December 2009, with citation rate equal to or higher than 20 times were collected for classification according to their publication year, publication form, subject distribution, regional and institutional distribution, frequency of authors appeared in those published papers, frequency of winning prizes, and sources of fund (national, ministerial, or provincial). Data were processed by Microsoft Excel software.

RESULTS

Altogether 64 scientific papers with high citation rate were published from 2000 to 2006. Original articles and expert forum accounted for 55 (86.0%). Twenty-one articles of clinical study were cited frequently, among them one was cited for 79 times. Articles dealing with subjects with popular interest or cutting-edge problems were cited frequently. Most articles winning high citation rate were originated from institutions located in Chongqing, Beijing, Shanghai, and Xi'an, etc. Those scientific papers which were instructed by specialists, with high level foundation and won prizes were cited with high frequency. The top 20 articles were mainly cited by excellent doctoral dissertations and master theses originated from 11 institutions for higher education, and source journals of Chinese Scientific and Technical Papers and Citations Database.

CONCLUSIONS

Authors should emphasize subject planning in order to compose papers with high quality. The editorial board should make arrangements with influential specialists with related skills for their contributions based on subjects of popular interest concerning the cutting-edge problems of the specific specialty, and pay close attention to papers on clinical study and those with funding from high levels, to improve impact of the articles.

New sources and instrumentation for neutrons in biology

Neutron radiation offers significant advantages for the study of biological molecular structure and dynamics. A broad and significant effort towards instrumental and methodological development to facilitate biology experiments at neutron sources worldwide is reviewed.

Efficacy of nisin in treatment of clinical mastitis in lactating dairy cows

Nisin is an antimicrobial polypeptide produced by Lactococcus lactis and is believed nontoxic to humans. The objective of this study was to evaluate a nisin-based formulation for the treatment of bovine clinical mastitis in lactating dairy cattle. A total of 92 cows with 107 clinically mastitic quarters were randomly assigned to nisin- (48 cows with 51 quarters) and gentamicin (GM)-treated (44 cows with 56 quarters) groups. In the nisin-treated group, cows received an intramammary infusion of nisin at a dose of 2,500,000 IU; in the GM-treated group, intramammary infusion of GM was administered at a dose of 0.8 g. Results indicated that nisin offered a clinical cure rate similar to GM (90.2 vs. 91.1%) and no difference in bacteriological cure rate than GM-treated group (60.8 vs. 44.6%, respectively). Proportion of the quarters with milk somatic cell counts <500,000 cells/mL was not different in the nisin-treated group (50.0 and 47.8%) compared with the GM-treated group (33.3 and 37.3%) 1 and 2 wk after treatment. Of 17 Staphylococcus aureus isolates, 82.5% were resistant to penicillin, and 35.3% to GM, but none of them to nisin. Nisin therapy eliminated 54.5% (6 of 11) of S. aureus IMI, whereas GM eliminated 33.3% (2 of 6). Nisin in milk (4.5 +/- 0.8 IU/mL) was detected only at 12 h following intramammary infusion, which was much lower than the upper limit (500 mg/mL) allowed as preservative in milk by the China authority. Because of its efficacy in the treatment of bovine clinical mastitis, especially resistant Staph. aureus-caused IMI, as well as its safety in humans, nisin deserves further study to clarify its effects on mastitis caused by different mastitis pathogens on a larger scale.

Structural restraints and heterogeneous orientation of the gramicidin A channel closed state in lipid bilayers

Although there have been several decades of literature illustrating the opening and closing of the monovalent cation selective gramicidin A channel through single channel conductance, the closed conformation has remained poorly characterized. In sharp contrast, the open-state dimer is one of the highest resolution structures yet characterized in a lipid environment. To shift the open/closed equilibrium dramatically toward the closed state, a lower peptide/lipid molar ratio and, most importantly, long-chain lipids have been used. For the first time, structural evidence for a monomeric state has been observed for the native gramicidin A peptide. Solid-state NMR spectroscopy of single-site (15)N-labeled gramicidin in uniformly aligned bilayers in the L(alpha) phase have been observed. The results suggest a kinked structure with considerable orientational heterogeneity. The C-terminal domain is well structured, has a well-defined orientation in the bilayer, and appears to be in the bilayer interfacial region. On the other hand, the N-terminal domain, although appearing to be well structured and in the hydrophobic core of the bilayer, has a broad range of orientations relative to the bilayer normal. The structure is not just half of the open-state dimer, and neither is the structure restricted to the surface of the bilayer. Consequently, the monomeric or closed state appears to be a hybrid of these two models from the literature.

Rheology of hyaluronan solutions under extensional flow

The extensional viscosity and the steady shear viscosity of sodium type hyaluronan (NaHA) in water with sodium chloride and/or sucrose and in DMSO solvent were measured. The extensional viscosities for HA in aqueous solution (0.05, 0.1, 0.3 w/v%) were constant at lower extensional rates, and then became strain thinning above a critical extensional rate. However, on adding sodium chloride, the extensional viscosity decreased and became strain thickening at higher extensional rates. Sodium ions shield the electrostatic repulsion between carboxyl residues of HA molecules and constrict the coil dimensions. The strain thickening of HA solution in the presence of sodium chloride at higher extension rates is due to the coil stretching. The addition of sucrose increased the extensional viscosity and shifted the critical extensional rate to lower strain rates. With increasing strain (shear) rates, extensional (shear) viscosities for HA aqueous solutions remained constant up to a critical extension (shear) rate; but they showed no plateau and decreased linearly in DMSO. It is clear that molecular interaction of HA in DMSO is stronger than that in aqueous solution. This should be attributed to the different conformations of HA in DMSO and in aqueous solutions.

Crystal structure of a ternary SAP-1/SRF/c-fos SRE DNA complex

Combinatorial DNA binding by proteins for promoter-specific gene activation is a common mode of DNA regulation in eukaryotic organisms, and occurs at the promoter of the c-fos proto-oncogene. The c-fos promoter contains a serum response element (SRE) that mediates ternary complex formation with the Ets proteins SAP-1 or Elk-1 and the MADS-box protein, serum response factor (SRF). Here, we report the crystal structure of a ternary SAP-1/SRF/c-fos SRE DNA complex containing the minimal DNA-binding domains of each protein. The structure of the complex reveals that the SAP-1 monomer and SRF dimer are bound on opposite faces of the DNA, and that the DNA recognition helix of SAP-1 makes direct contact with the DNA recognition helix of one of the two SRF subunits. These interactions facilitate an 82 degrees DNA bend around SRF and a modulation of protein-DNA contacts by each protein when compared to each of the binary DNA complexes. A comparison with a recently determined complex containing SRF, an idealized DNA site, and a SAP-1 fragment containing a SRF-interacting B-box region, shows a similar overall architecture but also shows important differences. Specifically, the comparison suggests that the B-box region of the Ets protein does not significantly influence DNA recognition by either of the proteins, and that the sequence of the DNA target effects the way in which the two proteins cooperate for DNA recognition. These studies have implications for how DNA-bound SRF may modulate the DNA-binding properties of other Ets proteins such as Elk-1, and for how other Ets proteins may modulate the DNA-binding properties of other DNA-bound accessory factors to facilitate promoter-specific transcriptional responses.

Electrochemistry in the presence of convective flow generated by acoustic streaming from a focused ultrasonic source

Limiting currents for the reduction of hexacyanoferrate-(III), i(lim), in aqueous solutions have been recorded in the presence of convective flow generated by a focused acoustic source with its main axis placed normal to the surface of a circular Au electrode embedded in a coplanar Teflon shroud. The results obtained could be fitted to a formula of the type -i(lim) = a(Uz(ss))b, where Uz(ss) is the axial velocity of the fluid along the center line of the lens evaluated at the focal point using computer simulation routines developed by Kamakura and co-workers (Kamakura, T.; Matsuda, K; Kumamoto, Y.; Breazeale, M. A. J. Acoust. Soc. Am. 1995, 97, 2740-2746). The fit yielded a value of b approximately 0.5 in agreement with that of rotating disk and impinging jet electrodes.

[An exploration of animal behavior screen platform for novel gene function in central nervous system]

For the purpose of large-scale screening of novel gene functions in mammalian nervous system, we have developed an animal behavior-monitoring platform employing antisense-oligo technology. Twenty genes of different categories were chosen from a low abundant gene (c)DNA sub-library of rat brain. Antisense oligo-nucleotides of these genes were designed and synthesized according to the homologues of the genes in mouse for mouse behavior tests. These antisense oligos were injected into the lateral ventricles of mouse brain using a Hamilton micro-syringe, with saline and oligos of scramble sequences as controls. These mice were tested with the following behavior model paradigms: metabolism, open field behavior, tail flick latency, and step-down test. Out of the 20 genes tested, 14 genes showed significant behavioral differences from the control groups at the level of P value less than 0.05 or 0.001 in different behavior animal models.

[Study on the photoluminescence spectrum of nickel passivation treatment of porous silicon]

A new method for electrolysis passivation treatment of porous silicom (PS) in NiCl2 is reported in this paper. The photoluminescence (PL) spectra of PS treated in different time is observed, the spectra show that peak intensity is 2.5 times stronger than that without treatment, peak wavelength is 33 nm blue shift when PS is treated properly. The phenomenon caused is that the results of the SiHx change into SiNix when replaced H by Ni on surface of PS.

[The effect of side chain structure on the excitation transfer and charge transfer processes in PPV/C60 composite system]

In this paper, we investigated the effect of side chains on the optical properties of PPV derivatives, the excitation transfer and charge transfer process in the PPV/C60 composite films. The results demonstrate that the absorption and PL emission bands of PPV shift towards lower photon energy with increasing of the length of PPV side chain, which indicates that energy gap of PPV derivatives become narrow with their side chain length increasing. In the PPV/C60 composite films, the emission of PPV derivatives was greatly quenched due to the efficient excitation transfer process between PPV and C60. We observed the absorption band of C60- located at 920 nm in the MD-PPV/C60 composite films, which reveals the existence of charge transfer process in the ground state of the composite films. This results show that the side chains of PPV derivatives not only influence the properties of absorbance and photoluminescence but also influence the electronic affinity of PPV polymers, which means that both physical and chemical properties of PPV can be monitored by controlling its side chain structure.

Ion solvation and association in LiClO4/sulfolane solution: a vibrational spectroscopic and molecular orbital study

Solvation interaction and ion association in solutions of lithium perchlorate/sulfolane have been studied by using infrared and Raman spectra as a function of concentration of lithium perchlorate. The band changes of antisymmetric OSO stretch, antisymmetric CSC stretch, -SO2 wag and twist suggest that there is an interaction between Li+ and sulfolane molecules, and the site of solvation is the oxygen atom of -SO2 group. The molecular orbital calculation supports this suggestion. On the other hand, the apparent solvation number was calculated, and the band fitting for the ClO4- band reveals the presence of contact ion pair, solvent separated ion pair and free ClO4- anion in the concentrated solutions.

[The Raman vibrational characteristics and assignments of three Schiff bases]

The Raman vibrational characteristics of three asymmetric Schiff bases were studied in this paper. By referring to the characteristic Raman spectra of substituent benzene and oxamidoxime compounds, the Raman vibrational modes of three Schiff bases were analyzed and assigned, respectively. The difference of their Raman spectra mainly arises from their different vibrational energy level resulting from the C-OH group to most extents. This result is of importance for further investigating the properties of these three new-type Schiff bases.

New insight on the origin of the unusual acidity of Meldrum's acid from ab initio and combined QM/MM simulation study

Ab initio molecular orbital and combined QM/MM Monte Carlo simulations have been carried out to investigate the origin of the unusually high acidity of Meldrum's acid. Traditionally, the high acidity of Meldrum's acid relative to that of methyl malonate has been attributed to an additive effect due to the presence of two E esters in the dilactone system. However, the present study reveals that there is significant nonadditive effect that also makes major contributions. This results from preferential stabilization of the enolate anion over that of Meldrum's acid due to anomeric stereoelectronic interactions. To investigate solvent effects on the acidity in aqueous solution, the relative acidities of Z and E conformers of methyl acetate have been determined in combined ab initio QM/MM simulations. There is significant solvent effect on the conformational equilibria for both the neutral ester and its enolate anion in water, leading to stabilization of the E stereoisomer. However, the computed solvent effect of 4.4 kcal/mol in favor of the E isomer of methyl acetate is largely offset by the favorable solvation of 3.4 kcal/mol for the E conformer of the enolate anion. This leads to an enhanced acidity of 3.4 kcal/mol for the (E)-methyl acetate in water over the Z conformer. In Meldrum's acid, it is the preferential stabilization of the enolate anion due to anomeric effects coupled with the intrinsically higher acidity of the E conformation of ester that is responsible for its high acidity.

Expression of DT-diaphorase and cytochrome P450 reductase correlates with mitomycin C activity in human bladder tumors

Mitomycin C (MMC) is activated by DT-diaphorase (DTD) and cytochrome P450 reductase (P450R). In cancer cell lines, MMC cytotoxicity is correlated with DTD and P450R expression levels. The present study investigated the relationship between enzyme expression/activity and MMC cytotoxicity in patient bladder tumors. DTD and P450R expression was detected by competitive reverse transcription-PCR and their activity was measured by bioreductive assays. The expression of DTD and P450R in patient tumors (n = 29), as ratios to beta-actin levels, varied from 0 to 90% and 0 to 29%, respectively. The DTD expression was significantly correlated with P450R expression (r(2), 0.32; P < 0.01), whereas the average DTD level was 2-fold higher than that of P450R (P < 0.01). Among the 29 tumors, 21 provided sufficient materials to evaluate tumor sensitivity to MMC. The concentration of MMC required to produce 50% inhibition (IC(50)) of DNA precursor incorporation for a 2-h treatment ranged from 0.17 to 18.1 microg/ml, indicating a 110-fold intertumor variation, with the high-grade and more invasive tumors being less chemosensitive compared with the low-grade and less invasive tumors. Tumor sensitivity to MMC, as indicated by the inverse of IC(50) values, was positively correlated with the expression of DTD (r(2), 0.28; P < 0.05) and P450R (r(2), 0.26; P < 0.05). Multivariate analysis indicates DTD expression and P450R expression as better determinants of MMC activity compared with other pathobiological factors (e.g., tumor grade, stage, and labeling index) that have been shown to significantly correlate with MMC activity. Eleven tumors were studied for the relationship between gene expression level and enzyme activity of DTD and P450R. The DTD activity was significantly correlated with the gene expression level (r(2), 0.84; P < 0.001). For P450R, there is a trend of a correlation between enzyme activity and its mRNA level, but the correlation was not statistically significant (r(2), 0.28; P = 0.09). These data indicate that the sensitivity of patient bladder tumors to MMC is correlated with the expression of DTD and P450R in tumors and suggest that the lower expression of these enzymes in the high-grade and more invasive tumors is a cause of the lower efficacy of intravesical MMC in these tumors.

Nuclear localization of G protein beta 5 and regulator of G protein signaling 7 in neurons and brain

The role that Gbeta(5) regulator of G protein signaling (RGS) complexes play in signal transduction in brain remains unknown. The subcellular localization of Gbeta(5) and RGS7 was examined in rat PC12 pheochromocytoma cells and mouse brain. Both nuclear and cytosolic localization of Gbeta(5) and RGS7 was evident in PC12 cells by immunocytochemical staining. Subcellular fractionation of PC12 cells demonstrated Gbeta(5) immunoreactivity in the membrane, cytosolic, and nuclear fractions. Analysis by limited proteolysis confirmed the identity of Gbeta(5) in the nuclear fraction. Subcellular fractionation of mouse brain demonstrated Gbeta(5) and RGS7 but not Ggamma(2/3) immunoreactivity in the nuclear fraction. RGS7 and Gbeta(5) were tightly complexed in the brain nuclear extract as evidenced by their coimmunoprecipitation with anti-RGS7 antibodies. Chimeric protein constructs containing green fluorescent protein fused to wild-type Gbeta(5) but not green fluorescent fusion proteins with Gbeta(1) or a mutant Gbeta(5) impaired in its ability to bind to RGS7 demonstrated nuclear localization in transfected PC12 cells. These findings suggest that Gbeta(5) undergoes nuclear translocation in neurons via an RGS-dependent mechanism. The novel intracellular distribution of Gbeta(5).RGS protein complexes suggests a potential role in neurons communicating between classical heterotrimeric G protein subunits and/or their effectors at the plasma membrane and the cell nucleus.

Rheological evidence of the gelation behavior of hyaluronan-gellan mixtures

It was found that solutions of calcium hyaluronate (CaHA) (0.1 to approximately 0.5 wt%) could form a gel by mixing with solutions of sodium type gellan (0.1 to approximately 0.5 wt%), although neither polymer by itself forms a gel at low concentrations (0.1 to approximately 0.5 wt% in this experiment). The rheological properties of CaHA-gellan mixtures were investigated by dynamic and steady shear measurements. Both storage shear modulus G' and loss shear modulus G'' for CaHA-gellan mixtures increased with increasing time, and tended to an equilibrium value after 1 h. After reaching steady values of G' and G", the frequency dependence of G' and G'' was observed. G' was always larger than G'' in the accessible frequency range from 10(-2) to 10(2) rad/s. The effects of pH and calcium ions were examined. Gel formation of the mixtures was promoted by decreasing pH and adding from 0.01 to 0.1 M calcium ions, but excessive calcium ions weakened the gel.

[The charge transferring between silver nanoparticles and R6G]

In this paper, we studied the charge transferring between silver nanoparticles and R6G molecules by UV-Vis absorption spectra, SERS and fluorescence spectra. The results indicate that the charge transferring process can be completed by forming complex between silver nanoparticles and R6G molecules. As a result, the absorption band of complex can be seen in the absorption spectra, the Raman modes of R6G are largely enhanced and the fluorescence of R6G is effectively quenched.

A Vibrational Spectroscopic Study of Ion Solvation and Association in Lithium Perchlorate/γ-Butyrolactone Electrolyte

The Raman and infrared (IR) spectra of γ-butyrolactone (BL) containing various concentrations of LiClO