Biomedical subjects

Z Yu

Publications and source records attributed to Z Yu.

At least 181 records · Page 10Linked to original sources

PubMed1999

[Effect of plasminogen activator inhibitor 1 gene transfer into mesangial cells on Extracellular matrix accumulation].

OBJECTIVE: To observe the influence of plasminogen activator inhibitor 1 (PAI-1) overexpression on extracellular matrix (ECM) accumulation of rat mesangial cells. METHODS: PAI-1/GFP green fluorescent protein fusion gene eukaryotic expression vector pCMX-PAI-1-GFP was constructed and delivered into cultured rat mesangial cells by liposome. PAI-1/GFP expression was observed by fluorescent microscope. FN, LN and Type IV collagen levels were measured by Northern blot analysis and ELISA method. RESULTS: Northern blot analysis, SDS-PAGE analysis and Western blot analysis demonstrated that PAI-1/GFP gene can be transcripted and translated in rat mesangial cells. PAI-1/GFP gene can express a specific protein. The recombinant PAI-1/GFP had significant inhibition activity on urokinase-type plasminogen activator and displayed autonomous fluorescence. The PA activity of cell supernatants decreased markedly in gene transfer group. FN, LN and Type IV collagen levels were higher than in a control group. CONCLUSION: Over-expression of PAI-1 gene leads to mesangial ECM accumulation. The changes of PA/PAI-1 activity in supernatants of cultured rat mesangial cells might be the key factor in ECM accumulation regulation.

Animals↗

PubMed1999

[The protective effects of thalidomide on acute liver failure].

OBJECTIVE: To understand whether thalidomide (Thal) has the same protective effects as it does in leprosy reaction type II, immunologic and inflammatory diseases. METHODS: D-Galactosamine (D-GalN, 600 mg/kg body weight, intraperitoneally) and lipopolysaccharide (LPS, 5 microg/rat, hypodermically) were used to produce a model of acute liver failure in Wistar rats. The mortality of the models was counted. The plasma peak levels of various cytokines and transaminases were measured. The pathological alterations of the livers were examined with hematoxylin and eosin stain under light microscopy. The expression of tumor necrosis factor (TNF)alpha mRNA was determined by dot blot hybridization combined with semiquantitative analysis. RESULTS: It was found that Thal could lower the mortality of the models (P < 0.05); reduce the peak levels of plasma cytokines, especially TNFalpha, and transaminases (P < 0.05), alleviate the degree of liver injury and suppress the expression of TNFalpha mRNA (P < 0.05). CONCLUSION: It is fully demonstrated that Thal has definite protective effect on acute liver failure, as it does in other diseases. Even though Thal possesses teratogenic effect in patients with pregnancy, it is still believed that Thal has an important curative significance in the treatment of patients who are not pregnant.

Animals↗

PubMed1999

[Morphological cure of cerebral arteriovenous malformations by endovascular therapeutics].

OBJECTIVE: To sum up the clinical characteristics and typical manifestation by analysing clinical materials from total embolized cerebral arteriovenous malformations (AVM) via endovascular embolization. METHODS: We reviewed clinical and image materials of 50 patients whose cerebral AVM were embolized entirely and found the cerebral AVM morphological cure by endovascular embolization after studying the size, position, artery supply, therapeutics and follow-up. RESULTS: 50 patients with cerebral AVM were embolized by endovascular therapy, accounting for 17% of all patients. Malformation lesions were medium or small type, with a diameter less than 3 cm, 95% of them were located in the tentorium superior. Terminal end blood supply was common to AVM and especially medium cerebral artery (MCA) or its branches. 97% of the patients were graded III or below by spectzler grading system. 70% of them had a history of intracranial hemorrhage and were cured by one therapy. CONCLUSIONS: It is a reliable and feasible method for morphological cure in cerebral AVM via endovascular therapeutics only, but case selection is important, that is, medium or small AVM with single branch terminal end blood supply in the tentorium superior.

Adolescent↗

PubMed1999

[The detection of high risk human papillomaviruses in papillary transitional cell carcinoma of urinary bladder].

OBJECTIVE: To investigate the histological evidence of high risk human papillomavirus infection in bladder cancer. METHODS: 52 cases of papillary transitional cell carcinoma of the urinary bladder were studied for the incorporation of high risk human papillomavirus type 16 and type 18 DNA by non-isotopic in situ hybridization (NISH). RESULTS: 19 of 52 cases (36.5%) were positive for HPV DNA with punctuate and/or diffuse purple-blue staining in the nucleus of cancer cells, including two cases positive both for HPV16/18. HPV DNA were predominantly expressed in superficial tumors. Among these positive tumors, adjacent normal epithelium and Brunn's nests also showed positive staining. Morphologically, HPV positive cells existed in the whole layer of papillary tumor cells, 3 of them presented koilocytoid change. CONCLUSIONS: HPV infection might be a common event in urinary bladder and a potential factor for carcinogenesis of bladder cells.

Adult↗

PubMed1999

[Motor-evoked potential in investigating neurologic function during spinal cord ischemia and reperfusion injury].

OBJECTIVE: To investigate the method monitoring the neurologic function of spinal cord ischemia and reperfusion injury. METHODS: Motor-evoked potentials (MEP)were monitored at different time points during ischemia and reperfusion of the lumbar spinal cord of the rat. RESULTS: MEP latency increased 15 minutes after ischemia (P < 0.01) and MEP amplitude decreased 25 minutes after ischemia (P < 0.01). MEP disappeared 40 minutes after ischemia and reappeared 5 minutes after reperfusion, but the latency was still longer and the amplitude was lower than the normal value (P < 0.01). The amplitude returned to normal 2 hours after reperfusion (P > 0.05) in contrast to the latency. 24 hours after reperfusion, the amplitude decreased again, and motor function of rat hind limbs was more decreased than that at early time of reperfusion (P < 0.05). CONCLUSION: MEP is a sensitive index for spinal cord ischemia and reperfusion injury.

Animals↗

PubMed1999

[Responses of normal rat kidney to different ischemic ways].

OBJECTIVE: To evaluate the effects of different ischemic ways on rat kidneys. METHODS: Male Wistar rat kidneys were divided into sham operation (group A), continuous ischemia (group B), intermittent ischemia (group C), ischemic preconditioning (group D), and delayed effect of ischemic preconditioning group (group E). The functional and morphologic changes and levels of MDA of the kidneys which suffered from different ischemia were assessed. RESULTS: The functional indexes of the group C were similar to that of the sham group. In the group B, D and E, the rats showed acute renal failure. Morphological findings showed that the groups B, D and E had severe tubular necrosis (+ + + - + + + +) 24 hours after operation. The group C showed light tubular necrosis (+). 30 minutes after reperfusion, the level of MDA was significantly lower in the group C than in the groups B, D and E (P < 0.01). CONCLUSIONS: In a given ischemic period, the injury effect of intermittent ischemia-reperfusion was much lower than that of continuous ischemia-reperfusion. Experimentally, ischemic preconditioning did not have protective effect on rat kidneys, including "classic protection" and "protection of second window". Intermittent ischemia-reperfusion did not increase OFR and lipid peroxidation injury.

Animals↗

PubMed1999

[Survey on traditional medicinal resources of Uncaria distributed in China].

OBJECTIVE: To make clear the botanical origin of medicinal Uncaria distributed in China and the situation of its use in folk medicines. METHODS: Collecting data and making on-the-spot investigation. RESULTS: There are thirteen medicinal plants which belong to Uncaria genus, and ten of them are commercially available. A clear idea was obtained of their geographical distribution, distribution features and practical experiences in folk application. CONCLUSION: This investigation is helpful in further researching and exploring the resources of Uncaria for medical use, as well as provides a scientific basis for production, management and safe use of crude drugs.

China↗

PubMed1999

[Morphological changes of external eyes before and after blepharoplasty].

OBJECTIVE: To discuss the morphological changes of external eyes before and after blepharoplasty. METHODS: A survey of 92 patients treated by blepharoplasty was carried out to compare the external eye morphology of pre-operation with that of post-operation. RESULTS: It was found significant differences in the post-operative patients, including the increased length and height of eyelids, and obvious changes of the length and angle of the exposed eyelashes. CONCLUSION: Blepharoplasty makes the eyelashes exposed and held up, and increases the up-to-low distance of eyelids. These changes promote the beauty of eyes.

Adolescent↗

PubMed1999

[Ectopic meningiomas of the head and neck (report of 10 cases)].

OBJECTIVE: To study the diagnosis and treatment of ectopic meningiomas of the head and neck. METHOD: A retrospective review was made of 10 patients with ectopic meningiomas of the head and neck, the pathological diagnosis was as follows: 2 case epithelial type, 2 case psammomatous type, 1 case transitional type, 1 case malignant meningioma and types of another 4 cases were unknown. RESULT: All patients were treated surgically, 4 patients with local recurrence were operated secondarily and no signs were observed with the follow-up of many years. CONCLUSION: Surgery was the choice of ectopic meningiomas of the head and neck.

Adolescent↗

PubMed1999

[Chiral separation of thio-glycidyl ether on amylose-chiral stationary phase by high performance liquid chromatography].

In the present study, we synthesized amylose-tris(phenylcarbamate), and used it as chiral stationary phase based on silica gel. This stationary phase offered a practically useful chiral separation medium. Amylose was allowed to react with an excess of phenylisocyanate in pyridine for 48 h. The obtained carbamate was dissolved in DMF and adsorbed on silica gel previously treated with 3-aminopropyltriethoxysilane. The mass ratio of the carbamate to the silica gel was 0.45/2.55. The four thio-glycidyl ethers were resolved on the amylose tris(phenylcarbamate) chiral stationary phase. Separation was carried out with a hexane/2-propanol mixture as mobile phase at a flow rate of 1.0 mL/min at room temperature. The effects of 2-propanol concentration on the retention and resolution have been investigated.

Amylose↗

PubMed1999

[Gas chromatographic method for estimating chemical stability of nitroquanidine propellant].

This paper describes a GC analytical method for nitroquanidine propellant instead of the tranditional methylviolet method. Operating conditions were as follows: TDX-01 packed column, 150-200 mesh, 800 mm x 3 mm i.d., at 150-170 degrees C with TCD. Released gases, CO2 and N2O contents in a sealed vessel packed with nitroquanidine were calculated according to the normalization of corrected peak areas of air, CO2 and N2O. Thus, the change in the chemical stability of nitroquanidine during the period of storage and thermal aging could be observed.

English Abstract↗

PubMed1999

[Chiral separation of thioglycidyl ether and glycidylselenide on cyclodextrin bonded stationary phase via high performance liquid chromatography].

beta- Cyclodextrin bonded chiral stationary phases (CD-CSP) were prepared after the method of Armstrong (CD-CSP I) and of Huang Tianbao (CD-CSP II). With the separation of o-, m- p-nitroaniline, it was found that the chromatographic properties of CD-CSP II was superior to that of CD-CSP I. Three racemes of thioglycidyl ethers and two racemes of glycidylselenides were resolved on CD-CSP II via high performance liquid chromatography. The mobile phase consisted of different volume ratios of methanol/0.3% triethylammonium acetate buffer solution(pH 5), and the eluate was detected with a UV-visible detector at a wavelength of 254 nm. With the increase of methanol volume ratio in the mobile phase, the retention time decreased rapidly, but within the range of methanol valume ratio 40/100 to 50/100, the separation factor only decreased slightly. The racemes examined contained aromatic groups and hydroxy groups which can form inclusion complexes and hydrogen bonding interactions with beta-cyclodextrin. The chiral separation of the racemes is successful with the mobile phase of V(methanol):V(buffer) = 40:60.

Aniline Compounds↗

PubMed1999

[Preliminary study of P19 gene from Bacillus thuringiensis subsp israelensis].

The P19 gene and cyt1A gene were obtained by PCR with 9.7 kb HindIII fragment containing P19 gene and cyt1A gene from 72 MD plasmid of Bt as a template. Digested PCR products were ligated to expression vector pUHE24 and transformed into E. coli XL-1. Three clones, LZ19 harboring P19 gene, LZcyt1A harboring cyt1A gene, LZ19A harboring P19 gene and cyt1A gene, were screened. The growth cure of cloned strains were determined under IPTG induction. The result showed that pLZ19 did not affect the growth of E. coli, pLZcyt1A is typically Lethal for E. coli, Lethal initial efficiency of pLZ19A is much higher than that of pLZcyt1A. Probably, this was a result that P19 gene enhanced initial expression of cyt1A gene in E. coli.

Bacillus thuringiensis↗

PubMed1999

[The effect of N+ implantation on SOD activity of Deinococcus radiodurans and induction of Mn-SOD].

The induction of Mn-SOD and effect of N+ of 20 keV implantation on SOD activity of D. radiodurans were investigated. The results were as follows: (1) SOD activity of D. radiodurans had a little change when implantation dose was less than 8 x 10(14) N+/cm2, and increased gradually from 8 x 10(14) to 60 x 10(14) N+/cm2, and then decreased rapidly; (2) the test of adding H2O2 and CHCl3-CH3CH2OH which could inhibit different types of SOD showed that most SOD activity of D. radiodurans was constituted by Fe-SOD in general physiology and less then 8 x 10(14)N+/cm2 dose, and higher implantation dose induced increase of Mn-SOD activity.

Deinococcus↗

PubMed1999

[Effects of the water-soluble extracts from the single herb of ganduqing against hepatitis B virus in vitro].

Comparing with Ara-Amp, the effects of the water-soluble extracts from the single herb of the formula for Ganduqing on HBeAg and HBsAg expression in 2.2.15 cells were studied. The results showed that the extracts of Serissa serissoides (DC) Druce, Hibiseus mutabilis Linn, Paedeuia scangens (Lour) Merr var tomentosa (BL) Hand-Mazz, Plumbago zeylanica L, Garcinia oblougifolia Champ and Begpnia edulia Levl had marked inhibition effects on HBeAg and HBsAg which expressed by 2.2.15 cells.

Antiviral Agents↗

PubMed1999

[Inhibiting effects of the ethanol-soluble extracts from the dried rhizoma of Garcinia oblougififolia on hepatitis B virus in vitro].

Comparing with Ara-Amp, the effects of the ethano-soluble extracts from the dried rhizoma of Garcinia oblougififolia Champ (GOC) on HBeAg and HBsAg expression in 2.2.15 cells, which came from transfected HepG2 cells with coloned HBV DNA, were studied. The results showed that the extracts of GOC had a marked inhibition effects on HBeAg adn HBsAg which expressed by 2.2.15 cells, the effective concentration was range from 195 to 780 micrograms/ml.

Antiviral Agents↗

PubMed1999

[Preservation of laryngeal function in surgical treatment of hypopharyngeal carcinoma].

OBJECTIVE: To study of the feasibility, the surgical techniques and the results of laryngeal function preservation in surgical treatment of hypopharyngeal carcinoma. METHODS: A retrospective review of 305 (279 males, 26 females, ages ranging from 14 to 77 years) cases with malignant neoplasms of the hypopharynx that were treated from 1978 to 1996 were accomplished. Of the 305 (stage I, 6; II, 12; III, 82; IV, 205) cases, 234 were originated from pyriform sinus, 21 from postcricoid, 35 from posterior pharyngeal wall and 15 from superior hypopharynx. Two hundred and eighty-five patients received 55-75 Gy postoperative radiotherapy. RESULTS: The overall 5 year survival rate of 305 patients was 44.8%; for stage I, the survival rate was 83%; stage II, 71%; stage III, 58% and stage IV, 36.5%. Of the 305 patients, 206 cases (67.54%, stage I, 6; II, 12; III, 65; IV, 123) were surgically treated with laryngeal functions preserved and 99 (32.46%, stage III, 17; IV, 82) total laryngectomy. There were no significant differences in 5-year survival between the functionally preserved group and none functional group. Among the 206 functional preserved patients, 139(67.5%) had all functions preserved (voice, respiration and deglutition) and 67(32.5%) partially preserved (voice and deglutition). CONCLUSION: Only a few patients (31/305, 10%) of hypopharyngeal carcinomas require total laryngectomy, and the preservation of the normal part of the larynx is feasible for the eradication of tumor and preservation of laryngeal function.

Adolescent↗

PubMed1999

[Immunohistochemical evaluation of micrometastases to cervical lymph nodes in supraglottic cancer].

OBJECTIVE: Supraglottic carcinomas of larynx tends to metastasize to cervical lymph nodes. The regular pathological method of diagnosis is easy to have the micrometastasis missed, and serial-sectioning is too difficult be used in the regular pathological examinations. The aim of this study was to evaluate the value of immunohistochemical assay in the detection of micrometastasis. METHODS: Monoclonal antibodies against cytokeratin (AE1/AE3) were used to detect the cervical lymph nodes of 46 cases (50 sides of neck) of supraglottic carcinoma with pathologically negative findings (pN0). RESULTS: Micrometastases were identified in 13 lymph nodes of 11 cases. CONCLUSION: It is suggested that the detection of lymph node micrometastases with immunohistochemical method is more sensitive than that of regular pathologic method. It is comparable to serial sectioning. Therefore, It is a valuable clinical method to detect the early lymph node metastasis.

Adult↗