[Relation among some cytokines, nitric oxide and the changing condition of cirrhosis of liver].
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Adult↗
Biomedical subjects
F Lu
Publications and source records attributed to F Lu.
[Single-pump on-line addition of modifier for supercritical fluid chromatography].
Modified CO2 as mobile phase is usually necessary for packed-column supercritical fluid chromatography. Single syringe pump was applied in this work to add modifier through a parallel connection device, which can maintain constant and stable volume fraction of modifier without any contamination of the pump. Viscosity of the modifiers (here are methanol and acetone) and the length of the CO2 pipe line/modifier pipe line can affect the volume fraction. Volume fractions of methanol and acetone were determined by gas chromatography and ultraviolet spectrometry respectively and their rules of variation were also examined. It shows that the volume fraction of methanol is lower than that of acetone under similar condition. With fixed modifierr line, the longer the CO2 line is, the higher the volume fraction will be. The new device can conveniently alter the nature and ratio of the modifier with quite stable volume fraction. The online addition device can tentatively replace the dual-pump system.
Chromatography, Supercritical Fluid↗
[Immune responses in mice vaccinated with recombinant plasmid pcDNA3 containing ROP1 gene from Toxoplasma gondii].
AIM: To observe the immune responses in BALB/c mice vaccinated with the constructed recombinant plasmid, pcDNA3, containing ROP1 gene from Toxoplasma gondii. METHODS: The plasmid DNA obtained by alkaline lysis were injected into the left leg of each mouse at a dosage of 100 micrograms. A booster vaccine was given using the same dosage two weeks later. Control groups were injected with the pcDNA3 blank plasmid and normal saline, respectively. 30, 50 and 70 days after the booster injection, the proliferation activity of T lymphocytes and the NK cell activity were determined using MTT assay, the number of CD4+/CD8+ T cells with indirect immunofluorescence assay and the titer of IgG antibody by ELISA. RESULTS: The spleens of mice enlarged obviously after immunization with pcDNA3-ROP1. The activity of proliferation of spleen T lymphocytes was higher in the immunization group than in the control groups; The NK cell activity in the immunization group was higher than those of control ones. The number of CD4+ T cells showed no obvious increase but CD8+ T cells obviously increased. The titer of IgG antibody in the immunization group showed no significant increase until 90 days later. CONCLUSION: Vaccination of mice with the recombinant plasmid, pcDNA3-ROP1, could elicit cellular and humoral immune response in mice.
Animals↗
[Cellular immune response in mice vaccinated with uv-attenuated Toxoplasma gondii ZS1 strain trophozoites].
AIM: To explore the protective effect and cellular immune response of uv-attenuated ZS1 strain trophozoites of Toxoplasma gondii in mice. METHODS: The ZS1 strain trophozoites of T. gondii were irradiated by uv-light with 2537 A wave length for 60 minutes. Mice were divided into 4 groups. Group 1 was vaccinated alone, group 2 was challenged with normal ZS1 trophozoites on d45 after vaccination, group 3 was infected alone, and group 4 was normal control. The changes in splenic T cell proliferation, level of CD4+ and CD8+ T cell, and NK cell activity were compared. RESULTS: Group 1 mice survived normally, no trophozoite, pseudo-cyst or cyst was detected in the tissues on d49 after vaccination. Group 2 mice survived longer than those of group 3. The T lymphocyte proliferation in response to soluble antigen of T. gondii was significantly enhanced in group 2, and suppressed in group 3. The level of CD4+ T cell in group 2 was decreased, resulting in a reverse of CD4+/CD8+ ratio. The NK cell activities in groups 1, 2 and 3 were all significantly increased. CONCLUSION: The uv-attenuated vaccine of T. gondii ZS1 strain could induce certain protective immunity against challenge infection, in which CD8+ T cell and NK cell might play an important role.
Animals↗
[Vibration studies of amphetamine and methamphetamine by micro Raman].
For the first time, we obtained and investigated the Raman spectra of amphetamine and methamphetamine by micro Raman with incidence excitation light 514.5 nm under the ambient environment. According to the fact that both molecules belong to single substituted benzene which has the symmetry of Cy2v, the attribution of Raman vibration modes in amphetamine and methamphetamine molecules was carried out by studying the spectral lines in the two spectra. The Raman line that only appeared in methamphetamine but could not be seen in any other drugs we have investigated was most possibly attributed to the stretching vibration between C-N(+)-C.
Amphetamine↗
[Studies of narcotics by micro Raman spectroscopy].
For the first time, the Raman spectra of eight kinds of narcotics were obtained and investigated by micro Raman. The results indicated that the Raman spectra were affected by the numbers and position of methyl in substituent groups. Under incidence light 514.5 nm and appropriate measurement condition, high quality Raman spectra of drugs with low fluorescence background were obtained. In addition, we discovered that narcotine and thedaine were very sensitive to strong light radiation. Finally, by comparing Raman spectra carefully for all drugs we measured the specific Raman peaks were given for the purpose of distinguishing different kinds of drugs.
Illicit Drugs↗
Religious and spiritual case reports on MEDLINE: a systematic analysis of records from 1980 to 1996.
OBJECTIVE: To undertake a systematic analysis of case reports involving religious or spiritual issues published between 1980 and 1996. DATA SOURCES: MEDLINE, the National Library of Medicine's bibliographic database covering the fields of medicine, nursing, dentistry, veterinary medicine, and the preclinical sciences. STUDY SELECTION: A search of 4,306,906 records indexed on MEDLINE from 1980 to 1996. DATA EXTRACTION: A total of 364 abstracts were found, then subjected to coding analysis. DATA SYNTHESIS: Categories were developed for (1) types of healthcare situations involving religious/spiritual issues, (2) religious and spiritual interventions, (3) collaboration between healthcare and religious professionals, (4) psychopathology and sensitivity themes, and (5) religious faith/spiritual path. Although all of these case reports involved religious and spiritual issues, only 45 (12%) explicitly mentioned a religious professional. Of these, only 8 (2%) indicated any collaboration between healthcare and religious professionals. CONCLUSIONS: A paucity of published case report literature exists on religious and spiritual issues (.008% of the MEDLINE records), indicating that the increasing acceptance of these factors by patients and healthcare professionals is not yet reflected in scientific and clinical journals. A need exists for more documented examples of collaboration between healthcare and religious professionals.
Humans↗
Escherichia coli purine repressor: key residues for the allosteric transition between active and inactive conformations and for interdomain signaling.
The Escherichia coli purine repressor, PurR, exists in an equilibrium between open and closed conformations. Binding of a corepressor, hypoxanthine or guanine, shifts the allosteric equilibrium in favor of the closed conformation and increases the operator DNA binding affinity by 40-fold compared to aporepressor. Glu70 and Trp147 PurR mutations were isolated which perturb the allosteric equilibrium. Three lines of evidence indicate that the allosteric equilibrium of E70A and W147A aporepressors was shifted toward the closed conformation. First, compared to wild-type PurR, these mutant repressors had a 10-30-fold higher corepressor binding affinity. Second, the mutant aporepressors bound to operator DNA with an affinity that is characteristic of the wild-type PurR holorepressor. Third, binding of guanine to wild-type PurR resulted in a near-UV circular dichroism spectral change at 297-305 nm that is attributed to the closed conformation. The circular dichroism spectrum of the E70A aporepressor at 297-305 nm was that expected for the closed conformation, and it was not appreciably altered by corepressor binding. Mutational analysis was used to identify an Arg115-Ser46' interdomain intersubunit hydrogen bond that is necessary for transmitting the allosteric transition in the corepressor binding domain to the DNA binding domain. R115A and S46G PurR mutants were defective in DNA binding in vitro and repressor function in vivo although corepressor binding was identical to the wild type. These results establish that the hydrogen bond between the side chain NH2 of Arg115 and the main chain CO of Ser46' plays a critical role in interdomain signaling.
Allosteric Regulation↗
Structure of human endothelin-2 gene and demonstration of common expression in human right atrial tissue.
The endothelins (ET) are a group of three vasoactive peptides also known to be involved in vascular remodeling. ET1 is the most extensively studied, but recent evidence has highlighted the role of the little investigated ET2 gene as a potential candidate gene in regulating blood pressure. To allow the future role of this gene to be studied the structure of human ET2 was characterized and intron/exon boundaries were determined. With this structural information and using reverse-transcriptase PCR technology we show that the ET2 gene is commonly expressed in human right atrial tissue. This work will allow a more detailed assessment of the role of this physiologically important gene in human essential hypertension.
Base Sequence↗
The DFRC Method for Lignin Analysis. 2. Monomers from Isolated Lignins.
Monomers released from derivatization followed by reductive cleavage (DFRC degradation) of lignins have been identified by mass spectra and/or comparison of their GC retention times with authentic compounds. The primary monomers from several isolated lignins representing softwoods, hardwoods, grasses, and dicots have been quantified by GC. Sources of the minor monomeric components have been rationalized on the basis of the DFRC mechanisms; products from cinnamyl alcohol endgroups, aldehydes, arylglycerols, and alpha-carbonyl units have been identified. From isolated lignins, the DFRC method produces its diagnostic primary monomers, the hydroxycinnamyl peracetates, with yields comparable to the production of monomers from other ether-cleaving analytical methods.
Journal Article↗
The DFRC Method for Lignin Analysis. 4. Lignin Dimers Isolated from DFRC-Degraded Loblolly Pine Wood.
Sixteen lignin dimers were directly isolated by gel permeation and reversed-phase TLC and HPLC from loblolly pine (Pinus taeda L.) sapwood following large-scale application of the new derivatization followed by reductive cleavage (DFRC) procedure. Their structures were elucidated by GC/MS and NMR. These dimers included representatives from all of the common interunit linkages in softwood lignins (beta-1, beta-beta, 5-5, beta-5, and 5-O-4). The DFRC procedure efficiently cleaves beta-aryl ethers, the major structural unit, so beta-ethers were not found among the dimeric products. All but two of the isolated dimers were guaiacyl-guaiacyl (from coniferyl alcohol-derived units in lignin); small amounts of p-hydroxyphenyl/guaiacyl beta-5 and beta-1 dimers were characterized. Several dimers have benzaldehydes as one unit-since aldehydes are not created by the procedure, they are either present in the native lignin or are formed during the minimal preparation of the wood. The dimers isolated and identified here will eventually allow their quantitation to aid in the structural analyses of wide-ranging plant materials.
Journal Article↗
Structure-based redesign of corepressor specificity of the Escherichia coli purine repressor by substitution of residue 190.
Guanine or hypoxanthine, physiological corepressors of the Escherichia coli purine repressor (PurR), promote formation of the ternary PurR-corepressor-operator DNA complex that functions to repress pur operon gene expression. Structure-based predictions on the importance of Arg190 in determining 6-oxopurine specificity and corepressor binding affinity were tested by mutagenesis, analysis of in vivo function, and in vitro corepressor binding measurements. Replacements of Arg190 with Ala or Gln resulted in functional repressors in which binding of guanine and hypoxanthine was retained but specificity was relaxed to permit binding of adenine. X-ray structures were determined for ternary complexes of mutant repressors with purines (adenine, guanine, hypoxanthine, and 6-methylpurine) and operator DNA. These structures indicate that R190A binds guanine, hypoxanthine, and adenine with nearly equal, albeit reduced, affinity in large part because of a newly made compensatory hydrogen bond between the rotated hydroxyl side chain of Ser124 and the exocyclic 6 positions of the purines. Through direct and water-mediated contacts, the R190Q protein binds adenine with a nearly 75-fold higher affinity than the wild type repressor while maintaining wild type affinity for guanine and hypoxanthine. The results establish at the atomic level the basis for the critical role of Arg190 in the recognition of the exocyclic 6 position of its purine corepressors and the successful redesign of corepressor specificity.
Adenine↗
The structure of PurR mutant L54M shows an alternative route to DNA kinking.
The crystal structure of the purine repressor mutant L54M bound to hypoxanthine and to the purF operator provides a stereochemical understanding of the high DNA affinity of this hinge helix mutant. Comparison of the PurR L54M-DNA complex to that of the wild type PurR-DNA complex reveals that these purine repressors bind and kink DNA similarly despite significant differences in their minor groove contacts and routes to interdigitation of the central C.G:G.C base pair step. Modeling studies, supported by genetic and biochemical data, show that the stereochemistry of the backbone atoms of the abutting hinge helices combined with the rigidity of the kinked base pair step constrain the interdigitating residue to leucine or methionine for the LacI/GalR family of transcription regulators.
Amino Acid Substitution↗
Caldesmon: binding to actin and myosin and effects on elementary steps in the ATPase cycle.
The actin binding protein caldesmon inhibits the actin-activation of myosin ATPase activity. The steps in the cycle of ATP hydrolysis that caldesmon could inhibit include: (1) the binding of myosin to actin, (2) the transition between any two actin-myosin states and (3) the distribution between inactive and active states of actin. The analysis of these possibilities is complicated because caldesmon binds to both myosin and actin and because each caldesmon molecule binds to several actin monomers. This paper reviews procedures for analysing these interactions and summarizes current information on the stability and dynamics of the interaction of caldesmon with actin and myosin. Possible effects of caldesmon on transitions within the ATPase cycle of actomyosin are also discussed.
Actins↗
[The expressions of p16, CDK4 and PCNA proteins in trophoblastic tumors].
OBJECTIVE: To evaluate the relationship between the regulatory factors in G1 phase of cell cycle and the cacrinogenesis of the trophoblastic cells. METHODS: The expressions of p16, cyclin-dependent kinase 4 (CDK4), proliferation cell nuclear antigen (PCNA) proteins in 18 cases of trophoblastic tumors, 30 cases of hydatidiform mole and 30 cases of normal villi were studied by immunohistochemical methods. RESULTS: The expressions of p16 protein between malignant trophoblastic tumors and normal villi were significantly different (P < 0.05). PCNA positive rate in p16 positive samples were markedly lower than that in negative samples (P < 0.05). The expressions of CDK4 among normal villi, hydatiform mole and trophoblastic tumors were not significantly different. Patients with positive p16 expression had a higher 3 year survival rate. CONCLUSION: p16 protein may inhibit trophoblastic cells proliferation, and p16 gene mutation may be an important factor in carcinogenesis of trophoblastic cells and proliferation out of control. P16 protein expression examination is helpful in prediction of patients prognosis.
Choriocarcinoma↗
[Domperidone and hyperprolactinemia].
Nine patients with hyperprolactinemia and one patient with pituitary microadenona were observed for 6 years. They were induced by administration of domperidone. The clinical characteristic of the 9 patients was summarized and analysed. The results suggest that prescribe domperidone for fertile women should pay more attention to its adverse effect on inducing hyperprolactinemia and even pituitary microadenona.
Adult↗
[ Measuring and assessing the quality of life of patients with pulmonary tuberculosis].
OBJECTIVE: To measure and assess the quality of life (QoL) of patients with pulmonary tuberculosis. METHOD: QoL of 228 patients with pulmonary tuberculosis and 228 healty controls were marked by MOS SF-36, QLI and KPS scales, and single and multiple stepwise regression analysis were made to evaluate factors affecting QoL. RESULT: The average total mark of SF-36, marks of physical functioning, role-physical, mental health, role-emotional, social functioning, vitality, bodily pain and general health were respectively 57 +/- 17, 65 +/- 28, 22 +/- 32, 61 +/- 20, 30 +/- 36, 54 +/- 27, 56 +/- 21, 65 +/- 24 and 53 +/- 15 in the pulmonary tuberculosis group, while 77 +/- 8, 84 +/- 23, 81 +/- 34, 75 +/- 18, 81 +/- 33, 83 +/- 23, 61 +/- 21, 75 +/- 24 and 72 +/- 20 in the controls. Statistically significant differences were found between the two groups (all P values < 0.01). The average marks of QLI and KPS were 7.4 +/- 2.0 and 77 +/- 17 respectively in the pulmonary tuberculosis group, and significant differences were also found comparing with the controls (9.6 +/- 0.8, 97 +/- 9) (P < 0.01). There were statistically significant correlation among the total mark of SF-36 and the marks of the above 8 subdividions in patients with pulmonary tuberculosis. The correlation coefficients between marks of SF-36 and QLI, KPS were 0.7841, 0.8931 respectively (P < 0.001). The factors affecting the marks of SF-36 of the patients were focus size of infection, counts of white blood cells, complications, elevated ALT and duration of disease. CONCLUSION: The SF-36 scale is suitable for measurement of QoL of patients with pulmonary tuberculosis. The QoL of patients with pulmonary tuberculosis declines. The main factors affecting the QoL of the patients are focus size of infection, counts of white blood cells, complications, elevated ALT and duration of disease.
Adult↗
[Analysis of molecular karyotype of Leishmania isolates from hilly foci and plain foci of China].
AIM: To analyse the molecular karyotypes of Leishmania isolates from hilly and plain foci of China. METHODS: Pulsed field gel electrophoresis(PFGE) was performed in 1% agarose at 6 V/cm in 0.5 x TBE at 14 degrees C with a pulse time of 60 s for 15 h and a pulse time 90 s for 9 h. RESULTS: Each isolate was resolved into 15 different EtBr-staining bands ranging in size from 200 to 2,200 kb, in which the karyotypes of 6 isolates from hilly foci were similar (including karyotypes of canine isolates similar with those of human isolates), and they were partly similar with those of L. infantum. The karyotypes of the two isolates from plain foci were similar, but the isolates from the two topographically different foci were different from each other. CONCLUSION: Homology exists between L. d. isolates from hilly foci and plain foci respectively, and exists in part between L. d. isolates from hilly foci and L. infantum; while heterogeneity exists between L. d. isolates from hilly foci and plain foci. The reservoir host, domestic dog, plays an important role as the infection source of leishmaniasis in the hilly foci of China.
Animals↗