Biomedical subjects
Publications and source records attributed to H Lu.
The most successful method for controlling the adsorption of proteins onto the capillary inner surface in CE is the modification of the capillary surface with coating. The advances of the method for preparation of the coated capillaries are systematically reviewed with 39 references in the present paper.
In this paper, a new method for determination of trace metal ions in complex matrices by chelation ion chromatography has been developed. In accordance to different analysis purpose, different interference should be selectively eliminated. On the chelating resins, all anions, alkali and alkaline earth metals could be eluted by ammonium acetate eluent (pH 5.5), tervalent cations could be eluted by pyrophosphoric acid/ammonium acetate eluent (pH 5.5). On sulfonated cation exchanger, heavy metals, transition metals, iron and aluminum could be eluted by hydrochloric acid/ethanol and oxalic acid/nitric acid eluents. Then, the concentrated lanthanides and transition metals (Pb, Cu, Cd, Ni, Zn and Co) were separated on bifunctional ion-exchange ion-exchange column by a proper concentration gradient of eluents, coupled with post-column spectrophotometric detection. Test samples could be injected directly into the column for analysis after the sample digestion. The detection limits of the method (signal-to-noise = 3:1) were at or below microgram/L level. The method has been systematically applied in rock, alloy, soil, plant and animal samples.
OBJECTIVE: To investigate the effect of Yangjing Decoction (YJD, a Chinese prescription of replenishing Kidney essence) in promoting follicular growth and its influence on blood supply of ovary and uterus. METHODS: Twenty-two cases with secondary amenorrhea and 4 cases of infertility with infrequent menstruation caused by follicle maldevelopment were treated with YJD. The blood supply of ovary and uterus in 7 cases was measured by colour Doppler before and after treatment. RESULTS: Of the 116 therapeutic cycles in 26 cases, there were 69 menstrual cycles (59.48%), 37 follicular maturation cycles (31.90%), 21 ovulation cycles (18.10%), and the follicular maturation rate was 84.62%, The disturbance in blood supply of ovary and uterus was improved remarkably along with follicular development by YJD in 7 cases. CONCLUSION: YJD could improve follicular development and blood supply of ovary and uterus.
OBJECTIVE: To explore the effective mechanism of Bushen Yugong Granule (BSYGG, a Chinese medicine preparation) in treating infertility due to uterine dysgeneia. METHODS: (1) Clinical study: Serum level of sex hormone and endometrial content of estradial receptor (ER) and progesterone receptor (PR) in follicle period of 60 patients (the tested group) were measured and compared before and after treatment, and the data were also compared with those of 70 normal women (the control group). (2) Experimental study: Rats were divided into the control group and 3 tested groups fed with different dose of BSYGG. Pathologic examination of pituitary, ovary and uterus of rats after BSYGG treatment, and serum levels of ER, PR were measured. Also, an estrogen activity experiment was adopted in some young cophorectomized rats. RESULTS: (1) Clinical study, the difference of serum sex hormone levels between the tested and the control group was insignificant. The percentage of patients in tested group with endometrial ER content over ++ was lower than that in the control group (46.9% vs 72.4%) significantly (P < 0.05), after treatment, it arised to 65.4% in test group, the change after treatment was significant (P < 0.05). (2) Experimental study: The number of follicle, weight of uterus and serum E2 level increased significantly after BSYGG treatment. The endometrial content of ER in the control group was 29.25 +/- 17.03%, while in the tested group, it was 67.75 +/- 24.56%-83.00 +/- 9.87% after treatment, the difference between the two groups was significant (P < 0.005). CONCLUSION: BSYGG has an estrogen-like activity, it could increase the endometrial content of ER, enhance the effect of estrogen on uterus and promote the uterine development, so as to elevate the fertilization rate.
Computer simulation studies using our newly developed mathematical model of human cardiovascular (CV) system were performed to investigate the effect of bladder coverage and inflation schedule of anti-G suit on G protection and CV response. The simulation results agree well with centrifuge experiments. The study demonstrates that additional +Gz protection provided by the extension of the bladder coverage depends mainly upon the pressure transmission efficiency to the underlying tissues and vessels. Although G tolerance increases clearly with the increase of suit inflation schedule, the tendency of increase seems slower when inflation schedule becomes higher than 10 kPa/G.
Apoptosis of nucleated cells is well known, but how about the unnucleated cells is still not elucidated. In the present paper, the morphological and biochemical features of the aged erythrocytes were observed and compared with the characteristic events of apoptosis. Membrane of aged erythrocytes tends to shrink, protrude, from vesicle and lose lipid asymmetry. Aged erythrocytes were removed by phagocytosis. Both of the events are very similar to the apoptotic nucleated cells. The authors suggested that aging of erythrocytes is also a process of apoptosis.
OBJECTIVE: To research into the law of androgen-receptor (AR) dynamic change in developing course of human HCC. METHOD: Dynamic measurement of AR in tumor and peritumorous tissue was performed in nude mice model with orthotopic transplanted human HCC. RESULT: Tumor nodules were present in 90% nude mice 4 weeks after transplantation, tumor necrosis was found in the 10th week, and remarkable necrosis occurred in the 12th week. The quantity of AR in tumor and peritumorous tissue was highest in the early stage of tumor (102.32 +/- 21.42 fmol/mg protein and 72.45 +/- 10.11 fmol/mg protein respectively), and then decreased progressively with time to the 10th week (40.98 +/- 21.11 fmol/mg protein and 53.39 +/- 7.01 fmol/mg protein respectively). The difference in AR between each two weeks was significant. CONCLUSION: Androgen promotes the development of tumor because of existence of AR, and its action may decline after establishment of tumor. Therefore, antiandrogen treatment may be ineffective after establishment of tumor.
We have successfully displayed human interferon-alpha lc/86D(IFN-alpha lc/86D) on the surface of the filamentous bacteriophage using a phagemid vector system (pCANTAB5E). The IFN-alpha lc/86D cDNA was fused to a DNA sequence encoding the amino-terminal domain of pIII, a minor coat protein exposed at one end of the phage. Fusion gene was packaged into phagemid particles upon superinfection with M13K07 helper phage. Expression of IFN-alpha lc/86D was verified by its reactivity with IFN-alpha l specific neutralizing antibodies and the phage displayed IFN-alpha lc86D was found to possess antiviral biological activity on VSV challenged WISH cells comparable to that of human recombinant IFN-alpha lb. These results demonstrate that IFN-alpha lc/86D can be displayed on phage in a correctly folded and functionally active form, and this system can be applicable to the sorting of a large repertoire of phage-displayed IFN-alpha lc/86D variants.
A new natural product, 4,4'-dihydroxy-a-truxillic acid (I) was isolated from Oldenlandia diffusa (Willd) Roxb. I is a derivate of cyclobutane, which were obtained chemically by photochemical reaction. Our works confirmed that the compound is a plant metabolite, not a secondary product produced during its extraction and isolation.
The effects of three Chinese ancient prescriptions, Bazhengsan, Pixiefenqingyin and Wulinsan were determined in vitro against 4 strains of Diplocous gonorrhoeaes. The results showed antibacterial activity of Bazhengsan was the highest, with a MIC from 6.25% mg/ml to 25 mg/ml. when the concentration of Bazhengsan was 100 mg/ml or over, all the Diplocous gonorrhoeae tested would be killed within ten minutes.
The effect of herbal preparation Qingjunyin (QJY) on the animal model of drug dependence was studied. After the morphinistic models of white rats and mice were made by ever increasing doses of morphine each time, the animals were divided into large dosage QJY group, small dosage QJY group, sustained morphine group and control group. The withdrawal symptoms were observed after naloxone was given to the animals intraperitoneally. The results showed that QJY groups withdrawal symptoms of the addicted white rats were alleviated, the number of jumps of the addicted mice was reduced, the scores of the principal symptoms of the animals were decreased, while the body weights of the animals were gained, comparing with the control group, the difference was significant (P < 0.01). The effects of QJY enhanced in the large dosage group, which suggests QJY has abstinence effects.
Plasma and urinary levels of ifosfamide (IF) enantiomers and their metabolites 2-dechloroethylifosfamide, 3-dechloroethylifosfamide, 4-hydroxyifosfamide, and isophosphoramide mustard were determined for control and phenobarbital-treated male Sprague-Dawley rats by using pseudoracemates and GC/MS and stable-isotope dilution analytical methods. For the control rats, the mean AUC for (S)-IF in plasma was greater than that for (R)-IF (R/S AUC ratio, 0.78) and the mean half-life of 41.8 min for (S)-IF was slightly longer than that of 34.3 min for (R)-IF. Phenobarbital pretreatment significantly decreased the AUC values for (R)-IF and (S)-IF, to 21 and 30% of the control values, respectively, and shortened plasma half-lives for both enantiomers [half-life for (R)-IF, 19.8 min; half-life for (S)-IF, 19.4 min]. The urinary excretion values for (R)-IF and (S)-IF were decreased to 41 and 30% of the control values, respectively. The overall amounts of the metabolites in urine were concomitantly increased. Additionally, there were significant reversals in both the R/S AUC ratio and the urinary excretion of 3-dechloroethylifosfamide. Moreover, the enantioselectivity for the generation of 4-hydroxyifosfamide and isophosphoramide mustard disappeared after phenobarbital treatment. These results strongly suggested that the 4-hydroxylation and dechloroethylation of IF enantiomers were mediated by different P450 isozymes or the same isozyme with different stereochemical selectivities.
In the present study, each of 43 cats was fed with a single metacercaria of Paragonimus pulmonalis and 2 cats (controls) with 2 metacercariae. They were killed 22-372 days postinfection. In the test group, 18 (41.9%) cats were infected, as well as the 2 cats in the control group. Among the 18 worms recovered from the test group, 9 found in the lungs were mature, whereas 5 mature and 4 immature worms were in the pleural cavity. Most eggs from worms encased in a cyst were passed in the feces. However, eggs from worms in the pleural cavity were only found on the lung surface and pleural cavity. Mature worms in cysts seemed to exhibit higher egg production capacity than those in the pleural cavity. Paired mature worms from a cyst laid more eggs than a single encysted mature worm in vitro at room temperature.
In this study, we observed the changes of glucocorticoid receptor (GR)-immunoreactivity (ir) and cell death in the rat hippocampal granule cell layer at various periods after adrenalectomy (ADX). Our results revealed that all of the rats shortly after ADX showed a rapid loss of GR-ir and subsequent appearance of degenerating cells in the granule cell layer. One month after ADX, however, about 80% of the rats displayed a restoration of GR-ir and the absence of degenerating cells in the granule cell layer, and this phenomenon was successively noted for 6 months. Hippocampal structural destruction 3 and 6 months after ADX was found in about 20% of the rats with loss of GR-ir in the granule cell layer; the ADX rats with even weak GR-ir in this area had a normal hippocampus. The treatment of rats with synthetic GR agonist, dexamethasone, immediately after ADX prevented the loss of GR-ir and significantly reduced the number of degenerating cells in the granule cell layer. Our results clarified that granule cell death after ADX was necessarily accompanied by the disappearance of GR-ir in the granule cell layer, suggesting that ADX-induced granule cell death is predicated on the loss of GR-ir and that the presence of GR-ir in this area may be important for granule cell survival.
This study was designed to assess whether the protective effect of ischemic preconditioning can be adapted for myocardium undergoing 6 h of no-flow ischemia. Twelve isolated rat hearts were either perfused with oxygen-bicarbonated Krebs-Henseleit buffer in the Langendorff mode for 35 min (n=6), or perfused in the same way for 20 min, following 5 min of global normothermic ischemia and 100 min of buffer-perfusion (n=6). The 12 hearts were then preserved for 6 h in HTK solution at 4 degrees C, followed by 30 min of reperfusion. Recovery of cardiac function, metabolic activity and intracellular free calcium concentration were compared between the two groups. After 6 h ischemia, the hearts that underwent preconditioning showed better recovery of left ventricular developed pressure (P<0.01), a lower end-diastolic pressure level (P<0.05), less creatine kinase leakage and a lower calcium concentration. There was no statistical difference in the recovery rate of coronary flow and leakage rate of LDH between the two groups. In conclusion, this experiment demonstrates that ischemic preconditioning improved myocardial functional recovery after 6 h of hypothermic ischemic preservation in the isolated rat heart. Preconditioning might be a potential mechanism for preserving the heart against long-term ischemia/reperfusion injury.
Hyaluronic acid (HA) is a glycosaminoglycan of the extracellular matrix. Its fragmentation by the hyaluronidase, secreted by tumor cells, facilitates tumor invasion and the HA degradation products generated stimulate angiogenesis. We report here that the HA-binding protein hyaluronectin (HN) inhibits the stimulatory effect of HA-derived fragments on the proliferation and migration of endothelial cells in vitro, and hampers the organization of endothelial cells into capillary-like structures. Since HN strongly inhibits endothelial cell adhesion to immobilized HA, it is postulated that HN acts by impairing the binding to endothelial cells of HA fragments generated by hyaluronidase, thereby neutralizing the effect of HA degradation products on angiogenesis. Our results reveal a new mechanism by which the angiogenesis induced by HA fragments is modulated by HN.
Urokinase-type plasminogen activator is implicated in cell invasion and migration. In this study, we provide evidence for the presence of urokinase-type plasminogen activator (3.5 +/- 1.5 ng/mg of cell protein) in isolated peripheral blood eosinophils, in comparison to 6.7 +/- 2.3 ng/mg of protein in neutrophils. Both immunocytochemical and immunogold staining of urokinase-type plasminogen activator on electron microscopy showed its localization in granules of resting cells. Mild stimulation by platelet-activating factor induced a translocation of urokinase-type plasminogen activator from the granules to the cell membrane and a formation of urokinase-type plasminogen activator capping, suggesting a role for urokinase-type plasminogen activator in eosinophil migration. The activation of eosinophils led to the release of factor(s) which, after activation of pro-urokinase-type plasminogen activator, induced an inactivation of generated urokinase-type plasminogen activator. Our results suggest that urokinase-type plasminogen activator is implicated in activated eosinophils invasiveness because the exposure of urokinase-type plasminogen activator is regulated both in space and time.
Activation domains are functional modules that enable sequence-specific DNA binding proteins to stimulate transcription. The structural basis for the function of activation domains is poorly understood. A combination of nuclear magnetic resonance (NMR) and biochemical experiments revealed that the minimal acidic activation domain of the herpes simplex virus VP16 protein undergoes an induced transition from random coil to alpha helix upon binding to its target protein, hTAFII31 (a human TFIID TATA box-binding protein-associated factor). Identification of the two hydrophobic residues that make nonpolar contacts suggests a general recognition motif of acidic activation domains for hTAFII31.