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Quan Zhu

Publications and source records attributed to Quan Zhu.

12 recordsLinked to original sources

Continuous medium theory for nonequilibrium solvation: IV. Solvent reorganization energy of electron transfer based on conductor-like screening model.

In this work the authors present some evidences of defects in the popular continuous medium theories for nonequilibrium solvation. Particular attention has been paid to the incorrect reversible work approach. After convincing reasoning, the nonequilibrium free energy has been formulated to an expression different from the traditional ones. In a series of recent works by the authors, new formulations and some analytical application models for ultrafast processes were developed. Here, the authors extend the new theory to the cases of discrete bound charge distributions and present the correct form of the nonequilibrium solvation energy in such cases. A numerical solution method is applied to the evaluation of solvent reorganization energy of electron transfer. The test calculation for biphenyl-cyclohexane-naphthalene anion system achieves excellent agreement with the experimental fitting. The central importance presented in this work is the very simple and a consistent form of nonequilibrium free energy for both continuous and discrete charge distributions, based on which the new models can be established.

Journal Article↗

Quality evaluation of Cordyceps through simultaneous determination of eleven nucleosides and bases by RP-HPLC.

A new RP-HPLC method has been developed for the simultaneous determination of 11 nucleosides and bases, including adenosine, cordycepin, cytidine, guanosine, inosine, thymidine, uridine, cytosine, guanine, thymine, and uracil in Cordyceps. Determination was achieved on a Zorbax 300SB C18 analytical column (4.6 x 250 mm id, 5 mm) using gradient elution with diode-array detection. All calibration curves showed good linearity (r2 > 0.9995) within the test ranges. The developed method was simple, rapid, and accurate, and showed good reproducibility for the quantification of 11 nucleosides and bases in natural and cultured Cordyceps with both intra- and inter-day variations of less than 1.8%. Furthermore, hierarchical clustering analysis based on the typical peaks of adenosine, cordycepin, and inosine in HPLC profiles from the 11 tested samples showed that natural and cultured Cordyceps were in different clusters, which could provide a means of discriminating between Cordyceps of different origins. Thus, adenosine, cordycepin, and inosine could be used as markers for quality control of Cordyceps.

Calibration↗

Continuous medium theory for nonequilibrium solvation: III. Solvation shift by monopole approximation and multipole expansion in spherical cavity.

According to the classical electrodynamics, a new and reasonable method about electrostatic energy decomposition of the solute-solvent system has been proposed in this work by introducing the concept of spring energy. This decomposition in equilibrium solvation gives the clear comprehension for different parts of total electrostatic free energy. Logically extending this cognition to nonequilibrium leads to the new formula of electrostatic free energy of nonequilibrium state. Furthermore, the general solvation shift for light absorption/emission has been reformulated and applied to the ideal sphere case with the monopole approximation and multipole expansion. Solvation shifts in vertical ionizations of atomic ions of some series of main group elements have been investigated with monopole approximation, and the variation tendency of the solvation shift versus atomic number has been discussed. Moreover, the solvation shift in photoionization of nitrate anion in glycol has been investigated by the multipole expansion method.

Journal Article↗

[Surrogate outcomes, intermediary outcomes and their application in TCM clinical efficacy evaluation].

In this paper, the concepts of surrogate outcomes and intermediary outcomes, their correlation with the primary outcome, how to select surrogate outcomes and intermediary outcomes and the particular requirements for using surrogate outcomes in assessing TCM clinical efficacy were discussed and described. It is difficult to evaluate clinical efficacy objectively and thoroughly by means of a single surrogate outcome for reason of the global characteristics of TCM, therefore, to rationally select such intermediary outcomes as important clinical symptoms, combination of several syndromes, patients' subject feeling, patients' satisfaction for treatment and quality of life, should be beneficial for objectively evaluating the efficacy of TCM intervention approaches.

Drugs, Chinese Herbal↗

[How to analyze and interpret the effective values in clinical trials].

The analysis of the effective value obtained in clinical trails should take account of both sides of its size and precision, for its interpretation, the general principles of: accuracy, explicitness and quantification should be complied. Criteria such as relative risk (RR), relative risk reducing rate (RRR), absolute risk reducing rate (ARR) and number needed to treat (NNT) an important clinical event, etc. are commonly used in the primary outcomes interpretation, while the methods to express the effective size and precision of surrogate outcomes and intermediary outcomes are needed to be further studied. Many problems for give expression to the outcome of TCM clinical trail still remain to be solved.

Clinical Trials as Topic↗

Continuous medium theory for nonequilibrium solvation: II. Interaction energy between solute charge and reaction field and single-sphere model for spectral shift.

On the basis of continuous medium theory, a model for evaluation of spectral shifts in solution has been developed in this work. The interaction energy between solute dipole and reaction field and the self-energy of the reaction field have been formulated through derivations. Applying the interaction energy expression together with the point dipole approximation to the case of spherical cavity produces new formulations of spectral shifts. The same expression of electrostatic free energy of the nonequilibrium state is achieved by integrating the change of the electrostatic free energy for a charging process. Moreover, generalized formulations evaluating spectral shifts have been established in the charge-potential notation, and the reduction of them to the point dipole case consistently leads to the same formulations of spectral shifts as those by interaction energy approach. Mutual supports provide convincing evidences for the reliability of the present results. In this work, attentions are particularly paid to the conclusion of zero self-energy of the reaction field, which is different from the previous theory. Reasoning and arguments are given on this point. From the present derivations, it is concluded that the spectral shifts of light absorption and emission were theoretically exaggerated in the past, in particular, by a factor of 2 for the spectral shift sum.

Journal Article↗

Macrophages are activated by 17beta-estradiol: possible permission role in endometriosis.

On the basis of the common occurrence of high concentration of estrogen and activated macrophages in patients with endometriosis, we postulate that interaction between 17beta-estradiol and macrophage may be an important affair in endometriosis. So our study was focused on the effect of 17beta-estradiol on macrophage. First morphology of macrophages was examined with environmental scanning electron microscopy. Increased size, extension of more microvilli, expression of retraction fibers and elaboration of membrane ruffles were detected in 17beta-estradiol treated macrophages. Then Nitrate and nitrite level in the supernatant was measured by the method of Griess and iNOS expression was analyzed using immunohistochemical staining. It showed that 17beta-estradiol could induce NO release from peritoneal macrophages and expression of iNOS was increased. Also more TNF-alpha in supernatant that was measured by MTT via L929 cell was produced by macrophages under the inducing of 17beta-estradiol. Furthermore, [Ca2+]i, which was viewed by microscope in a laser scanning confocal unit, elevated 39.8% in peritoneal macrophages after 17beta-estradiol 100 nmol/L treated. The results above demonstrated that peritoneal macrophage had been activated in both morphology and cytokine line when interaction with 17beta-estradiol, which indicated that macrophage activated by 17beta-estradiol might play a permission role in development of endometriosis.

Animals↗

The homeodomain protein CDP regulates mammary-specific gene transcription and tumorigenesis.

The CCAAT-displacement protein (CDP) has been implicated in developmental and cell-type-specific regulation of many cellular and viral genes. We previously have shown that CDP represses mouse mammary tumor virus (MMTV) transcription in tissue culture cells. Since CDP-binding activity for the MMTV long terminal repeat declines during mammary development, we tested whether binding mutations could alter viral expression. Infection of mice with MMTV proviruses containing CDP binding site mutations elevated viral RNA levels in virgin mammary glands and shortened mammary tumor latency. To determine if CDP has direct effects on MMTV transcription rather than viral spread, virgin mammary glands of homozygous CDP-mutant mice lacking one of three Cut repeat DNA-binding domains (DeltaCR1) were examined by reverse transcription-PCR. RNA levels of endogenous MMTV as well as alpha-lactalbumin and whey acidic protein (WAP) were elevated. Heterozygous mice with a different CDP mutation that eliminated the entire C terminus and the homeodomain (DeltaC mice) showed increased levels of MMTV, beta-casein, WAP, and alpha-lactalbumin RNA in virgin mammary glands compared to those from wild-type animals. No differences in amounts of WDNM1, epsilon-casein, or glyceraldehyde-3-phosphate dehydrogenase RNA were observed between the undifferentiated mammary tissues from wild-type and mutant mice, indicating the specificity of this effect. These data show independent contributions of different CDP domains to negative regulation of differentiation-specific genes in the mammary gland.

Animals↗

[Effect of TCTS on experimental endometriosis of rats].

OBJECTIVE: To study the effect of TCTS on endometriosis rats. METHOD: On the model of surgical induced rat endometriosis, weight and pathological changes of endometrial transplant and serum hormones were observed. RESULT: Weight of endometrial transplants was reduced by TCTS 11.2 g.kg-1 and 22.5 g.kg-1 and transplants of TCTS treated rat showed poorly developed epithelium, thinner stroma, fewer stromal cells and glands. At the same time elevated serum E2, FSH and LH were reduced by TCTS. CONCLUSION: TCTS can inhibit the growth of endometrial transplants, which is related with serum hormone, especially E2.

Animals↗

[Effect of extract from shenghua decoction on myoelectric activity of rabbit uterine muscle in the latest period of pregnancy].

OBJECTIVE: To elucidate the difference between uterus body and cervix under the intervention of Shenghua decoction, and to observe the rabbit uterine muscle in the latest period of pregnancy for the way of myoelectric activity. METHOD: PowerLab/8s was used to record myoelectric activity of rabbit muscle in uterus body and cervix which was in a general anaesthesia state induced by urethane. RESULT: Myoelectric activities of rabbit uterine smooth muscle in the latest period of pregnancy was enhanced in vivo by being treated with Shenghua decoction 40 mg x kg(-1) (P < 0.01) while cervix myoelectric activities had no significant change (P < 0.05). CONCLUSION: Myoelectric activities of rabbit uterine muscle in the latest period of pregnancy are enhanced by being treated with Shenghua decoction so its hemostatic effect can be represented via the constriction of uterus body. Shenghua decoction is beneficial for child delivery because cervix myoelectric activities have no significant change under the intervention of Shenghua decoction while the myoelectric activities of uterus body are increased significantly.

Action Potentials↗

CDP binding to multiple sites in the mouse mammary tumor virus long terminal repeat suppresses basal and glucocorticoid-induced transcription.

Mouse mammary tumor virus (MMTV) is transcribed at high levels in the lactating mammary gland to ensure transmission of virus from the milk of infected female mice to susceptible offspring. We previously have shown that the transcription factor CCAAT displacement protein (CDP) is expressed in high amounts in virgin mammary gland, yet DNA-binding activity for the MMTV long terminal repeat (LTR) disappears as mammary tissue differentiates during lactation. CDP is a repressor of MMTV expression and, therefore, MMTV expression is suppressed during early mammary gland development. In this study, we have shown using DNase I footprinting and electrophoretic mobility shift assays that there are at least five CDP-binding sites in the MMTV LTR upstream of those previously described in the promoter-proximal negative regulatory element (NRE). Single mutations in two of these upstream sites (+691 or +692 and +735 relative to the first base of the LTR) reduced CDP binding to the cognate sites and elevated reporter gene expression from the full-length MMTV LTR. Combination of a mutation in the promoter-distal NRE with a mutation in the proximal NRE gave approximately additive increases in LTR-reporter gene activity, suggesting that these binding sites act independently. Mutations in several different CDP-binding sites allowed elevation of reporter gene activity from the MMTV promoter in the absence and presence of glucocorticoids, hormones that contribute to high levels of MMTV transcription during lactation by activation of hormone receptor binding to the LTR. In addition, overexpression of CDP in transient-transfection assays suppressed both basal and glucocorticoid-induced LTR-mediated transcription in a dose-dependent manner. These data suggest that multiple CDP-binding sites contribute independently to regulate binding of positive factors, including glucocorticoid receptor, to the MMTV LTR during mammary gland development.

Animals↗