Biomedical subjects

Y Feng

Publications and source records attributed to Y Feng.

At least 145 records · Page 8Linked to original sources

PubMed2000

dl-3-n-butylphthalide reduces brain damage in mice with closed head injury.

OBJECTIVE: To investigate the protective effect of dl-3-n-butylphthalide (NBP) as an anti-cerebral ischemic drug on brain damage 24 h after closed head injury in mice. METHODS: Closed head injury was induced by dropping a 50-g weight from a height of 18 cm on a metal impounder resting on the parietal bone in mice. RESULTS: The neurotraumatic model induced impairment of memory function, significant cerebral edema, and disruption of the blood-brain barrier. dl-3-n-butylphthalide (50 mg.kg-1) given intraperitoneally 5 minutes and 60 minutes after the onset of closed head injury was found to attenuate the impairment of memory function (P < 0.05), alleviate brain edema in the injured cerebral cortex (P < 0.05), and reduce extravasation of plasma protein bound to Evans blue dye by 63.5% (P < 0.01). NBP was also shown to increase the activity of choline acetyltransferase in the injured cortex to 0.83 +/- 0.21 ng.min-1.mg-1 (P < 0.01, compared with 0.48 +/- 0.14 ng.min-1.mg-1 of vehicle group). CONCLUSION: NBP provides therapeutic response in experimental closed head injury.

Animals↗

PubMed2000

Therapeutic strategy in the management of stage II-IV epithelial ovarian carcinoma.

OBJECTIVE: To investigate the optimal time of debulking in stage/II to stage IV epithelial ovarian carcinoma, considering corresponding advantages of both surgery and chemotherapy. METHODS: From January 1989 to December 1996, ninety-five stage II to stage IV ovarian cancer patients were treated under two different regimens. Group A-76 cases (2 cases in IIa stage, 4 cases in IIb stage, 6 cases in IIc stage, 58 cases in IIIc stage and 7 cases in IV stage) was managed according to a traditional surgery-chemotherapy regimen; and group B-19 cases (17 cases in IIIc stage and 2 cases in IV stage) was managed with a chemotherapy-surgery-chemotherapy regimen. RESULTS: The optimal debulking rate (no macroscopic residual or residual < 2 cm) in group A was significantly lower than in group B, being 32.9% (25/76) and 68.4% (13/19), respectively (P < 0.001). The average survival time of those with a residual focus > 2 cm was shorter than those with a residual focus < 2 cm, in both groups. Sixteen out of the 51 patients with a residual focus > 2 cm had a second debulking operation, among whom 7 had preoperative chemotherapy. All of these 7 patients had either no residuals or residual < 2 cm. In 9 cases without preoperative chemotherapy, the residuals were all > 2 cm. The average survival time among these two groups were significantly different (P < 0.01). CONCLUSION: (1) For those patients in whom optimal debulking was clinically assessed to be possible, timely operation is mandatory. (2) For those inoperable advanced cases, chemotherapy-surgery-chemotherapy regimen is recommended. (3) For those with residuals > 2 cm and were assessed to be difficult to eradicate during second-look operation, multi-route chemotherapy (intro-arterial, intraperitoneal, and systematic) should be given before going on the second debulking operation. Positive attitude and proper regimen would offer better results. (4) A multicenter prospective study would give more decisive conclusion.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2000

[A study on IL-5 and IL-10 in the modulation of asthmatic airway inflammation in murine models].

OBJECTIVE: To observe the time-course profile of airway inflammation in murine asthma model, and to analyze the dynamic profile of pro-inflammatory factor IL-5, and inflammtion-suppressing factor IL-10 in the airway. METHODS: An animal model of asthma was established by OVA sensitizing-challenging BALB/C mice. At seven points (0 h, 8 h, 24 h, 48 h, 96 h, days 7 and days 14) in the time course after challenge, bronchoalveolar lavage (BAL) was performed. Total cell counts, cell differential, eosinophil (EOS) counts and percentages were examined and levels of two Th2 cytokines, IL-5 and IL-10, were detected by ELISA. RESULTS: After OVA challenge, total cell counts, EOS counts and EOS percentages in BALF were increased significantly. EOS count increased at 8 h, formed a plateau from 24 h to 48 h, declined at 96 h, reduced approximately to control from days 7 to days 14. IL-5 in BALF elevated at 8 h, maitained at high level from 28 h to 96 h, decreased at days 7. The dynamic changes of IL-5 was in synchronism with that of EOS counts, a positive correlation being identified. No significant difference was found between IL-10 in BALF before and after challenge. A close correlation between EOS counts and IL-5/IL-10 ratio was demonstrated (r = 0.9, P < 0.001). CONCLUSION: IL-5 and IL-10 up- and down-regulate asthmatic airway inflammation respectively, and their interaction may play an important role in inflammatory progress and resolution.

Animals↗

PubMed2000

[Management of severe maxillary deficiency through distraction osteogenesis with external distraction device].

OBJECTIVE: To demonstrate a practical method for advancement of the midface using Le Fort I osteotomy and gradual distraction technique. METHODS: With the use of an external adjustable, rigid distraction device, we treated 6 patients with severe maxillary hypoplasia. Ages ranged from 11 to 15 years. They all underwent modified Le Fort I osteotomies assisted by gradual distraction. Four days postoperatively, distraction began at the rate of 1 mm/day for about 2 weeks. 4 weeks with the fixed distraction appliance and 6 weeks with a removable night-time face-mask retention, we then analyzed all those preoperative and postoperative protocols. RESULTS: Predictable results were obtained. Midface advancement ranged from 8 to 13 mm. A satisfactory class I or II molar relationship is achieved. The aesthetic results are excellent. Up to now, no relapses have been observed. CONCLUSIONS: This method of modified Le Fort I midface advancement has been shown to be clinically practical and effective.

Adolescent↗

PubMed2000

[Damage to intra- and extrahepatic bile duct after hepatic artery embolization].

OBJECTIVE: To study the pathogenesis, treatment and prevention of bile duct damage arising from hepatic artery embolization. METHODS: Five patients with intra- and extrahepatic biliary damage resulting from hepatic artery embolization. Of these patients, 4 were due to hepatic artery embolization for hepatic haemangioma, and 1 was due to injecting TH (methacrylate) compound into the hepatic artery during operation. The hepatic artery was injected with ethanol so as to evaluate liver damage in experimental rats. RESULTS: All patients were found to have damage to intra- and extrahepatic bile duct at the hilum with biliary hepatocirrhosis; 4 of them received intrahepatic bile duct jejunal anastomosis and bile duct stent. Experiment result revealed obliteration of the bile duct and necrosis of the liver around the portal tract area. CONCLUSIONS: Arterial embolization of hepatic haemangioma may cause severe biliary damage.

Adult↗

PubMed2000

[Time course of TGF beta 1 and VEGF expression in experimental vein grafts].

OBJECTIVE: To investigate time course of TGF beta(1) and VEGF expression and their role in intimal hyperplasia. METHODS: In situ hybridization and immunohistochemical technique were used to detect the time course of intimal hyperplasia, time course of TGF beta(1) mRNA and protein expression of TGF beta(1) and VEGF. RESULTS: After autogenous vein replacement, the obvious neointima was seen at 2 weeks, and peaked at 8 weeks. The expression of TGF beta(1) mRNA peaked at 1 week and decreased gradually, but at 10 weeks, its positive cell percentage was still 10.1%. Both protein expression of TGF beta(1) and VEGF in VSMCs increased from 24 hours after grafting and peaked at 2 weeks. Their positive cell percentages were 40.6% and 36.6% respectively. After 4 weeks, their expression decreased at 8 weeks, the positive cell percentages were 8.9% and 13.8% respectively. CONCLUSIONS: TGF beta(1) plays an important part in ECM accumulation by promoting ECM synthesis and decreasing ECM degradation. VEGF plays the key role in reendothelialization. They may affect each other and cooperated in the formation of intimal hyperplasia.

Animals↗

PubMed2000

[A study on the changes of blood levels of type III procollagen and type IV collagen in relation to artery blood gas and lung function in patients with cor pulmonale].

This study was conducted to explore the changes of PC III (type III procollagen) and C IV (type IV collagen) in the serum in patients with chronic pulmonary heart diseases. The blood levels of PC III and C IV in 25 patients with chronic pulmonary heart diseases and 20 normal subjects were measured by radioimmunoassay and were analysed in relation with the artery blood gas and pulmonary function parameters. The results revealed that the blood levels of PC III and C IV in the patients were significantly higher than those in normal subjects, and were negatively correlated with PaO2, FEV1%, MBC and MMEF (P < 0.05, P < 0.01). The results suggest that the blood levels of PC III and C IV of patients with chronic pulmonary heart diseases are significantly increased and significantly correlated with pulmonary function damage and hypoxia.

Aged↗

PubMed2000

[Preliminary isolation and identification of neurotrophic factors sensory neurons in spinal dorsal horn of embryonic chicken].

Our previous studies have demonstrated that the extract from dorsal horn of embryonic chicken can promote apparently the neurite growth of spinal ganglion during development. In this study, we investigated progressively the neurotrophic factors for primary sensory neurons in spinal dorsal horn. The tissues of spinal dorsal horn from five hundred Hamburger Stage-40 embryonic chickens were taken. After homogenization and centrifugation, the supernatant was subjected to SDS-polyacrylamide gel electrophoresis (SDS-PAGE) for analyzing the protein in dorsal horn. The simple protein band fishing by cell (SPBFC) technique was employed in finding the protein bands with neurons attached, and then such protein bands, were taken and transferred to nitric cellulose paper for Western hybridization analysis by antibody for NGF, BDNF, NT-3 and GDNF respectively. The results of SPBFC showed that some neurons were attached to gel within the scope of mobility relative front (Rf) 0.10-0.19, 0.30-0.35, 0.50-0.55, 0.60-0.67 and 0.90-0.94 respectively, indicating there were some neurotrophic factors for maintaining neuron survival in the above Rf scope. Moreover, the result of Western hybridization showed that the positive hybridization bands in each scope were that of NGF, BDNF, GDNF; NGF, BDNF, NT-3; NGF, BDNF, NT-3; NGF, NT-3 and BDNF, NT-3 respectively; indicating that the neurotrophic effect of spinal dorsal horn tissue on primary sensory neurons involves NGF, BDNF, NT-3 and GDNF. These also suggest that the neuronal survival effect in each Rf scope involves at least two or more neurotrophic factors.

Animals↗

PubMed2000

[Morphological observation on dorsal root ganglion neurons of embryonic chicken in vitro].

The aim of this study was to explore the developmental character of neurons from dorsal root ganglion (DRG) of embryonic chicken in vitro. The DRG neurons of Hamburger stage 35 were cultured and prepared at 0, 1, 2, 3, 4, 5, 7, 14 and 21 days respectively. The number of neuronal survival was counted at each cultured stage (observed area: 2.5 x 10(5) microns 2) and the morphological change of neurons in vitro was observed and compared with that of neurons in vivo. The results showed the counts of neuronal survival were 94 +/- 4, 83 +/- 6, 67 +/- 4, 65 +/- 7, 68 +/- 5, 71 +/- 9, 73 +/- 6, 22 +/- 4, and 0 respectively; the cultured neuronal shape during 48 h incubation was mainly oval or sphere, similar to that of neurons in vivo. However, the shape of some neurons changed into cone or shuttle after three days incubation, while the neuronal shape in vivo did not change. These findings indicate that only some of neurons can survive and grow and the lifetime is limited in vitro, on the other hand, the developmental character of neurons in vitro may be different from that of neurons in vivo.

Animals↗

PubMed2000

[Identification of Listeria species in 167 kinds of foods].

Through preliminary identification of isolation of Listeria species in six types foods, which consisted of 167 kinds of foods, we found both S-form and R-form colonies were suspected colonies of Listeria species, and some of them were catalase-negative, urease-positive, methyl red(MR) negative and Voges-Proskauer(VP) negative. The results showed that S-form, catalase-positive, urease-negative, MR-positive and VP-positive colony should not be used as the strict criteria for the identification of Listeria.

Animals↗

PubMed2000

[Changes of cytokines secreted by human oral mucosa keratinocytes from oral submucous fibrosis in vitro].

OBJECTIVE: To assess the significance of oral mucosa keratinocytes (KCs) and cytokines in the development of oral submucous fibrosis (OSF). METHODS: KCs were obtained and cultured from the buccal mucosa of healthy subjects who did not chew areca nut and patients with OSF who chewed areca nut. Then radioimmunoassay and enzyme-linked immunosorbent assays were employed, and endothelin (ET) and transforming growth factor beta 1 (TGF beta 1) were quantified in culture supernatants. RESULTS: The mean levels of ET and TGF beta 1 secreted by OSF-KC were 96.983 +/- 17.802 pg/ml and 4661.641 +/- 783.893 pg/ml respectively, which were higher than these secreted by NM-KC (P < 0.05); There was a positive correlation between the levels of ET and TGF beta 1 secreted by OSF-KC. CONCLUSION: External stimuli such as areca nut components may induce the development of OSF by activating and stimulating the keratinocytes to secret a series of cytokines, including ET and TGF beta 1. It is speculated that ET and TGF beta 1 may be the contributing factors in the pathological features noted in OSF.

Endothelins↗

PubMed2000

[Enhancement of BCG-induced hBD-1 mRNA expression in human pulmonary gland epithelial cells].

Using reverse-transcription PCR (RT-PCR) and Northern blot analysis, the present authors found an enhanced expression of the human beta-defensin 1 (hBD-1) gene in the SPC-A-1 cells challenged with heat-killed M. Bovis Bacille Calmette-Guerin (BCG). The enhanced expression of hBD-1 mRNA was dose- and time-dependent. This result indicated a significant progress in the work of developing a new antimicrobial strategy that enhances mucosa antibiotic peptide expression for the prevention and treatment of mucosal infections.

BCG Vaccine↗

PubMed2000

[Study of modeling and simulation of the multi-branch cardiovascular system].

By the Power Band Graph(PBG) method, this paper presents a computer simulation model of the multi-branch cardiovascular circulation system, which describes the blood fluid dynamic law in the cardiovacular system by the state equation. The model gives a minute description on physiological characters of cardiovascular circulation system (CVS). An integrate computer model on CVS has been established. The model can simulate physiological characters of cardiovascular circulation system and get the simulation data and the curves of CVS hemodynamics variables. The model can be used widely in the field of physiological system simulation study, medical study, and computer-aided instruction.

Computer Simulation↗

PubMed2000

[Applying pharmaceutical effect indexes to screen out the preparation technology of xiaobanxia added fuling granules].

After having adopted vomiting animal model created by filling stomach with cuprum sulfuricum and after having selected incubation period and vomiting index as our measuring and commenting indexes. We prepared decoction of Xiaobanxia added Fuling granules by applying orthogonal experimental method with four factors and three levels to proceed a preferable choice of extracting technology. The superior extracting technology became A2B3C2, namely: comminuting medicinal materials into coarse powder, for the first time, adding 9 times dosage of water and decocting for 45 minutes, for the second time, adding 5 times dosage of water and decocting for 30 minutes, condensing the filtrate to light paste (specific gravity 1.25-1.27, assaying at 25 centigrade), preparing decoction of Xiaobanxia added Fuling granules with a proportion as below:light paste:amylin:saccharose powder = 1:3:0.5.

Animals↗

PubMed2000

[Study on the technological process of including volatile oil of Baizhu with beta-cyclodextrin].

The volatile oil of Baizhu was included with beta-CD. The factors affecting the formation of the inclusion compounds were researched by L9(3(4)) orthogonal test. The ratio of the oil in inclusion compounds and recovery of inclusion compounds were used as criteria in the test. The best conditions for inclusion were A2B3C1, that is, the compounds should be formed in the aqueous solution containing beta-CD and oil with a raio of 8:1, aqua destillate and beta-CD with a ratio of 4:1 for two hours.

Analysis of Variance↗

PubMed2000

[Mutations in the connexin 26 gene in patients with nonsyndromic hearing impairment].

OBJECTIVE: To determine the prevalence and characteristics of deafness-causing mutations in Connexin 26(Cx26, GJB2) gene in Chinese with nonsyndromic hearing impairment(NSHI). METHODS: Study subjects are all Chinese including 16 infants with sporadic congenital deaf-mutism, 39 patients with autosomal recessive hereditary hearing loss, 30 patients with autosomal dominant hereditary hearing loss and 100 normal adults. The subjects were screened for base variations by single-strand conformational polymorphism (SSCP) analysis of the amplified products of polymerase chain reaction (PCR). Those who were found have abnormal conformational band were sequenced. RESULTS: Five kinds of polymorphism were found in 15 cases of controls and six kinds of polymorphism in 10 patients. No mutation was found in Cx26 gene in Chinese with autosomal recessive NSHI. Heterozygous deletion AT at position 299-300 of Cx26 cDNA, which results in premature chain termination, was found in a pedigree with autosomal dominant hereditary nonsyndromic hearing loss. CONCLUSION: The prevalence of deafness-causing mutations in Cx26 gene in Chinese with autosomal recessive NSHI maybe is lower than that of other ethnic groups. Heterozygous deletion AT at position 299-300 of Cx26 cDNA can lead to autosomal dominant hereditary hearing loss (DFNA3).

Asian People↗

PubMed2000

[Transposition of expanded cervical-shoulder skin flaps for the repair of cicatricial contracture deformity of neck].

OBJECTIVE: To evaluate the efficacy of expanded cervical-shoulder skin flap in the treatment of cicatricial contracture deformity of neck, and improve the method for the repair of soft tissue defect of neck. METHOD: 12 patients with cicatricial contracture of neck were treated by pre-expanded cervical-shoulder skin flap and then transposition for the reconstruction of the defect after cervical scar resection. RESULT: All the 24 flaps were survived. Postoperative follow-up for 6 months to one year showed that the cervico-mandibular function and the external appearance of the flaps were satisfactory without swelling and contracture. CONCLUSION: Pre-expanded cervical-shoulder skin flap is available for the treatment of cicatricial contracture deformity of neck.

Adolescent↗

PubMed2000

[Study on optical properties and synthesis of nanosized GeO2-SiO2 glasses].

The compound material of nm size particles GeO2-SiO2 was synthesized through hydrolysis of Si(OC2H5)4 and GeCl4 with pH-2. A heat-treatment was carried out for samples at 100-1,200 degrees C in air. Its optical property was determined by UV-Vis spectrum. We have found that the absorption edge of spectrum shifted progressively to longer wavelengths. The quantum size effect of nanocrystals appears because crystals grow and the energy of optical band gap reduces due to the influence of temperature. By the analysis of X-ray diffraction we have observed the process in which the structure of particles changed from disorder into order, and the particles with size 5-10 nm came into obviously as temperature increased until 1,100 degrees C.

Gels↗