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Biomedical subjects

R Wang

Publications and source records attributed to R Wang.

At least 163 records · Page 9Linked to original sources
PubMed2001

[Pharmacodynamics study of suanzaoren decoction extracted by different technological process].

OBJECTIVE: To select the optimal technological process for Suanzaoren decoction. METHOD: The effects of extracts from different technological processes on spontaneous motion and sleep time in mice induced by pentobarbital sodium (subthreshold dosage) were studied. RESULTS: Both the decoction and 95% alcohol extract of Suanzaoren possess sedative and hypnotic effects. CONCLUSION: Suanzaoren aqueous decoction was selected as the optimal technological process.

Animals↗
PubMed2001

[Effects of exogenous adenosine 5'-monophosphate on proliferation and apoptosis of small intestinal epithelial cells].

The effect of exogenous adenosine 5'-monophosphate (AMP) on proliferation and apoptosis of a normal rat small intestinal epithelial cell line, IEC-6, was investigated. Proliferation of IEC-6 was measured by MTT. Cell cycle and apoptosis was determined by flow cytometry. Expression of Bax was detected by immunohistochemistry. The results showed that AMP remarkably inhibited the proliferation of IEC-6 in a dose- and time-dependent way. AMP also significantly changed the distribution of cell cycle, arrested cells in S phase and enhanced apoptosis by inducing Bax expression.

Adenosine Monophosphate↗
PubMed2001

[Culture and identify the endothelial cells of human umbilical vein].

In order to improve the routine culture method for vascular endothelial cells, endothelial cells of vein from newborn umbilical cord were successfully isolated with combined using 0.1% collagenase and 0.25% trypsin (1:1). The endothelial cells were further abrated by mechanical method. The composition of culture medium was simplified by not adding vascular endothelial cell growth factor and heparin. The cultured cells were verified as vascular endothelial cells by morphology, ultramicromorphology and immunohistochemistry.

Cell Culture Techniques↗
PubMed2001

[The effect of rIFN alpha-2b on mice NK cell activity].

OBJECTIVE: This animal experiment was made to study the effect of the recombined interferon alpha-2b(rIFN alpha-2b) on natural killer cells activity of mice spleen in vivo, and by way of this, to test the activity of rIFN alpha-2b. METHODS: BALB/c mice were given rIFN alpha-2b subcutaneously. The inhibiting 3H-TdR intaking method was used to test the NK activity of spleen cells of BALB/c mice. RESULTS: The NK cell activity levels of the high-dose group, the mid-dose group and the low-dose group were 65.19 +/- 17.56, 44.19 +/- 14.30 and 35.46 +/- 17.49, respectively. CONCLUSION: rIFN a-2b can enhance NK cells activity observably and its effect is dose dependent.

Animals↗
PubMed2001

[Detection of radiation-induced apoptosis in nasopharyngeal carcinoma].

OBJECTIVE: To investigate the pathological changes after radiotherapy and its clinical significance of nasopharyngeal carcinoma (NPC). METHOD: Paraffin-embedded tissue blocks obtained from 30 cases of NPC before and during radiotherapy were used in this study. Using terminal oxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) and HE staining, the spontaneous and radiation-induced apoptotic rate (AR) were examined, and the pathological changes of NPC tissues before and after radiotherapy were compared. RESULT: The AR of radiation-induced apoptosis was significant higher than that of spontaneous apoptosis, but the AR was decreasing and the differentiation of proliferatic tumor clonogehic cell getting better during radiotherapy of NPC. CONCLUSION: The process of apoptosis was accelerated and the differentiation of proliferative tumor clonogehic cell getting better during radiotherapy of NPC.

Adolescent↗
PubMed2001

[Determination of thyroxine enantiomers in human plasma with normal high performance liquid chromatography-chiral complex exchange mobile phase].

An HPLC method was developed with normal HPLC-chiral complex mobile phase for the separation and determination of D- and L-thyroxine enantiomers (D- and L-T4) in human plasma. The method includes extraction of thyroxine from plasma and separation of thyroxine enantiomers on HPLC silica column with chiral eluent containing L-proline, cupric acetate and triethylamine (TEA). The sensitivity of the method was 0.1 mg/L. The precisions of inter-day and intra-day, linearity, extraction recovery, and stability of T4 enantiomers in plasma and in deproteinized plasma were determined for the validation of the method. Baseline enantioseparation of the compounds containing D- and L-T4 was achieved. Meantime we determined the concentrations of D-T4 and L-T4 in plasma of 15 volunteers with euthyroid, hypothyroid and hyperthyroid symptoms. Liquid chromatographic method based on the described procedure was useful for the determination of D- and L-thyroxine in patient plasma and for pharmacokinetics investigation.

Chromatography, High Pressure Liquid↗
PubMed2001

[Determination of isophthalic acid in polyethylene glycol terephthalate fiber by high performance liquid chromatography].

The isophthalic acid(IPA) is present in polyethylene glycol terephthalate(PET) at small level, but plays an important role for the properties of polyester fiber. Thus the PET sample was hydrolysated by 100 g/L of sodium hydrate in methanol at 70 degrees C during 10 h and finally assayed by HPLC. A reversed-phase high performance liquid chromatographic method for the separation of isophthalic acid from terephthalic acid(TPA) has been developed. The operating conditions were Novapak C18 column, methanol-water(15:85, V/V)(pH3) as mobile phase with the flow rate of 1.0 mL/min and UV detection wavelength at 254 nm.

English Abstract↗
PubMed2001

[Effects of intracerebroventricular administration of endomorphin-1 on blood pressure in anesthetized rats].

AIM: To observe the effects of intracerebroventricular administration of endomorphin-1 on blood pressure in anesthetized rats and to assess its mechanism. METHODS: Variations of mean arterial pressure (MAP) were observed after icv injection of endomorphine-1 in rats. The effects of i.v. or icv of various blockers, naloxone, phentolamine, propranolol, atropine and N omega-nitro-L-arginine, on the variation of MAP caused by endomorphin-1 were observed. RESULTS: Endomorphin-1 was shown to decrease MAP. The decrease in MAP was blocked by naloxone. Pretreatments with icv phentolamine and propranolol showed no effect on the vasodepression induced by icv endomorphin-1. However, pretreatment with icv atropine (25 micrograms.kg-1) attenuated the vasodepression. Pretreatments with i.v. phentolamine, propranolol and N omega-nitro-L-arginine showed no effect on the vasodepression induced by icv endomorphin-1. But, pretreatment with i.v. atropine (50 micrograms.kg-1) and bilateral vagotomy attenuated the vasodepression. CONCLUSION: Intracerebroventricular administration of endomorphin-1 produces vasodepressor response in anesthetized rats, which is mediated by opioid receptor. The vasodepression is associated with the central M cholinoceptor and the excitation of the vagus.

Anesthesia↗
PubMed2001

[Effects of endomorphins and their analogs on cardiovascular system].

AIM: To analyze the effects of endomorphins (EMs) and their analogs ([D-Pro2]EM-1, [D-Ala2]EM-1, [D-Pro2]EM-2 and [D-Ala2]EM-2) on the cardiovascular system of anestetized rats and to study its mechanism. METHODS: Responses to EMs and their analogs were investigated in the systemic vascular bed of rats and the mesenteric microarteria of Bufo gargarizans. Responses to EMs were investigated on the hindquarters of the rat vascular bed under constant-flow conditions and on the isolated rabbit thoracic aorta strips. RESULTS: The EMs and their analogs showed dose-related (10(-9)-10(-6) mol.L-1, i.v.) and naloxone-sensitive (2 mg.kg-1, i.v.) hypotension in mean arterial pressure of rats with similar duration and vasodilatation in mesenteric microarteria of Bufa gargarizans. The sequence of potencies was EMs > [D-Pro2] EM-2 > [D-Ala2]EM-2 > [D-Ala2]EM-1 > [D-Pro2]EM-1. EMs were shown not to relax the isolated rabbit thoracic aorta strips without endothelium. EMs, however, relaxed them with endothelium significantly. This action was blocked by Nx (10(-5) mol.L-1) and L-NNA (10(-4) mol.L-1). CONCLUSION: The significant hypotensive activity of EMs and their analogs is mainly associated with their vasodilatation, which is related to the release of NO from vascular endothelium, and their potency is not completely related to their affinity for mu-opiate receptor.

Animals↗
PubMed2001

[A chemiluminescence flow sensor for vitamin B1].

AIM: To determine vitamin B1 in pharmaceutical preparations by chemiluminescence (CL) flow sensor. METHODS: When 200 microL of Na3PO4 was passed through an anion exchange column, K3Fe(CN)6 was eluted from the resin and then mixed with the vitamin B1 stream containing NaOH to product CL, by the fast oxidation reaction between vitamin B1 and K3Fe(CN)6 in alkaline solution. RESULTS: The CL emission intensity was correlated with the vitamin B1 concentration in the range 1.0 x 10(-5) to 1.0 x 10(-3) mol.L-1 and the detection limit was 8.0 x 10(-6) mol.L-1 (3 sigma). A complete analysis, including sampling and washing, can be performed within 2 min with a relative standard deviation of less than 4.0%. CONCLUSION: The vitamin B1 flow sensor was stable for over 200 analyses and has been applied successfully to determination of vitamin B1 in pharmaceutical preparations.

Injections↗
PubMed2001

[The significance of nuclear factor kappa Bp65 (NF kappa Bp65) expression on the vascular endothelial cells of rectum adenocarcinoma of human].

OBJECTIVE: This study inquired into the mechanism of cancer vascular metastasis. METHODS: The immunohistochemical method was adopted in determining the expression of intercellular adhesion molecule-1 (ICAM-1) and nuclear factor kappa B (NF kappa Bp65) on the peritumoral rectum tissues and metastatic lymph nodes of 8 patients and on the rectum tissues and lymph nodes of 5 normal human subjects. Also, the method of in situ hybridization was employed in detecting the binding site of NF kappa Bp65 on vascular endothelial cells. RESULTS: It was found that the proteins of ICAM-1 and NF kappa Bp65 were expressed on the vascular endothelial cells of the rectum adenocarcinoma patients, and there was a NF kappa B binding consensus sequences on ICAM-1 promoter in the vascular endothelial cells of the rectum adenocarcinoma patients. When DIG-AKP labeled 38-bp oligonucleotide probe was used, there was no expression of ICAM-1 and NF kappa Bp65 on the vascular endothelial cells of the normal human lymph node and rectum tissues. CONCLUSION: The above data suggest that the activation of ICAM-1 promoter may critically depend on NF kappa Bp65 homodimers or heterodimers binding to a variant kappa B site on the vascular endothelial cells of human rectum adenocarcinoma. These may indicate the potential roles of NF kappa B in cancer metastasis, thus giving clues to the development of a novel anti-metastasis strategy.

Adenocarcinoma↗
PubMed2001

[The effect of AG490 on NK activity and lymphocyte transformation of PBMC].

OBJECTIVE: To examine the effect of AG490 on NK activity and lymphocyte transformation. METHODS: Using MTT colorimetry to detect cell survival, NK activity and cell proliferation. RESULTS: AG490 inhibited IL-2 and PHA induced peripheral blood mononuclear cell proliferation, and it inhibited NK activation. CONCLUSION: As an inhibitor of JAK, AG490 can influence the function of normal cells.

Cell Division↗
PubMed2001

[Effect on proliferation and apoptosis of human lingual carcinoma cells cotransfected by bax and p53 genes].

OBJECTIVE: To investigate the effects on proliferation and apoptosis of human cancerous cells cotransfected by bax apoptosis-inducing gene and p53 tumor suppressor gene. METHODS: The chimeric gene pSV-CIP-bax-CAT was constructed in which bax gene was flanked upstream by a 217 bp fragment(+822(-)+1093) of the first intron and a 317 bp promoter fragment of human a 1(I) collagen gene. Human lingual carcinoma cell line Tca 8113 (LCC) in culture was respectively transfected with pSV-CIP-bax-CAT, and cotransfected with pSV-p53-CAT and pSV-CIP-bax-CAT by using the transfection reagent DOSPER. RESULTS: Immuno-slot blot and ELISA demonstrated that the expression of bax and p53 genes increased remarkably in the transfected and cotransfected LCC, compared with the controls (LCC transfected with pSV-CIP-CAT and LCC). MTT colorimetric assay, TUNEL fluorenscence microscopy and flow cytometry showed that foreign bax or p53 gene inhibited the LCC growth and induced apoptosis (23.9% and 26.1% of inhibitory rate by bax gene and p53 plus bax genes respectively). CONCLUSION: The ectopic expression of the bax gene in the LCC promoted by the cis-acting elements of human a1 (I)collagen gene has obviously synergistic effect on the proliferation and apoptosis of the LCC contransfected with p53 gene plus bax gene for 48 hours.

Apoptosis↗
PubMed2001

[Multiple factors analysis of intraoperative bleeding and recurrence of juvenile nasopharyngeal angiofibromas].

OBJECTIVE: To study the effect of surgical treatment of juvenile nasopharyngeal angiofibromas and the factors influencing intra-operative bleeding and recurrence. METHODS: Thirty-four patients with juvenile nasopharyngeal angiofibromas treated surgically in Chinese PLA General Hospital between 1986 and 1999 were studied retrospectively. The relationship between surgical treatment, intraoperative bleeding, recurrence and age, duration, staging, preoperative treatment, times of previous operation, operative approaches was statistically analyzed. RESULTS: The tumors were totally resected in 30 patients, and five patients(16.7%) recurred during a mean follow-up of 77 months. The mean recurrence time after operation was 3.2 months (1-6 months). The amount of intraoperative bleeding correlated well with the age, duration, staging, preoperative treatment, and surgical approaches (P < 0.05), but not with times of previous operation (P > 0.05). Recurrence was not correlated with the age, duration, preoperative treatment and surgical approaches (P > 0.05), but correlated with staging (P < 0.05). CONCLUSION: The factors significantly influencing the intraoperative bleeding were the age, duration and staging. Recurrence was correlated with the tumor stages, incomplete resection or the exceedingly malignant activity of the tumor. Radiotherapy, with a dose of 30Gy, is an adjuvant therapy for incompletely resected, or residual tumors.

Adolescent↗
PubMed2001

[Ultrastructure of surfactant-like multilamellar bodies in the human nose].

OBJECTIVE: To study the distribution of the surfactant-like multilamellar bodies in the human nose. METHODS: Fourteen specimens obtained from the inferior turbinate, middle turbinate, uncinate process and maxillary sinus were examined under the electron microscope. RESULTS: The surfactant-like multilamellar bodies were identified in the epithelium on the lateral wall and maxillary sinus. CONCLUSION: The existence of surfactant-like multilamellar bodies in the human lateral nasal wall and maxillary sinus were confirmed. It is necessary to have further study for its effect in the nose both physiologically and pharmacologically.

Adolescent↗
PubMed2001

[Effect of p14ARF gene on cell growth of human laryngeal tumor cells and expression of endogenous p53 protein].

OBJECTIVE: To explore the inhibitory effect of p14ARF on the cell growth of laryngeal carcinoma and the expression on endogenous p53. METHODS: p14ARF cDNA was transferred to the cell line Hep-2 of squamous cell carcinoma of the larynx by gene transfer to study the cell cycles and the expression of endogenous wild type p53 using flow cytometry, polymerase chain reaction(PCR) and Western-Blotting. RESULTS: Expression of p14ARF significantly affected the Hep-2 cell growth. The clone-forming efficiency of the Hep-2 cells transferred with p14ARF was 57%, compared with empty vector pcDNA3. The number of 48 hours after transfer with p14ARF cDNA at both G0/G1 and G2/M was two fold as the control. The expression of endogenous wild type p53 was significantly enhanced. CONCLUSION: Expression of p14ARF can up-regulate the expression of endogenous wild type p53 and inhibit the Hep-2 cell growth of human laryngeal squamous cell carcinoma at both G0/G1 and G2/M.

Carcinoma, Squamous Cell↗
PubMed2001

[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.

Electrochemistry↗