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Biomedical subjects

S Zhang

Publications and source records attributed to S Zhang.

At least 577 records · Page 32Linked to original sources
PubMed1999

[Random amplified polymorphic DNA analysis on Curcuma wenuujin and C. sichuanensis].

OBJECTIVE: To discuss the problem of classifying Curcuma for Medical purposes. METHOD: RAPD was used to detect the DNA polymorphism within and among Curcuma wenyujin, C. sichuanensis and C. aromatica. RESULT: It is hard to differentiate between C. wenyujin and C. sichuanensis from the DNA level. The relationship between C. wenyujin and C. aromatica was also analyzed. CONCLUSION: Based on the morphological and chemical data, it is suggested that these two species should be combined into one and that classification based on peduncle central or peduncle lateral may not be right. This method will help to some degree to solve the problem of certifying the medicinal plant Curcuma.

Curcuma↗
PubMed1999

[Studies on distribution of magnetic-bearing microspheres in rabbits].

OBJECTIVE: To evaluate the distribution of magnetic-bearing microspheres (MPMs) in rabbits. METHODS: The distribution of intravenously injected 99mTc-labelled MPMs in rabbits at different intervals of magnetic field applied and different magnetic field intensity was investigated by using an externally applied magnetic field and measuring the radio-activity at the rabbit head and other organs. RESULTS: MPMs have the properties of targeted distribution, as positive correlation between targetic radio-activity and times and intensity of magnetic field. CONCLUSION: MPMs may be better used in the therapy of cavernous hemangiomas.

Animals↗
PubMed1999

[Effects of alumina particle-size on mechanical properties of alumina-glass composite].

OBJECTIVE: To study the effects of alumina particle-size on mechanical properties of alumina-glass composite. METHODS: Alumina compacts were prepared by isostatic press method and sintered at 1400 degrees C for 2 hours with two various particle-size alumina. Alumina-glass composite was made by infiltrating partially sintered porous alumina with glass at 1200 degrees C for 4 hours. RESULTS: The strength and fracture toughness of nanometre alumina-glass composite were 358.2 MPa, 2.38 MPam1/2 respectively. The strength and fracture toughness of micrometer alumina-glass composite were 432.2 MPa, 5.12 MPam1/2 respectively. Image analysis of SEM micrograph showed that porous rate was about 11.5% in the nanometer alumina-glass composite, 1.2% in the micrometer alumina-glass composite, and there was more glass composition in the nanometer alumina-glass composite than that in the micrometer alumina-glass composite. CONCLUSION: The alumina volume percentage and porous rate play an important role in the strength and fracture toughness of alumina-glass composite.

Aluminum Oxide↗
PubMed1999

[Long-term results of surgical treatment of intractable Menière's disease for control of vertigo].

OBJECTIVE: To acquire the long-term (an average of over 10 years follow-up) results of surgical treatment of patients with Meniere's disease for control of vertigo. METHOD: Endolymphatic sac surgery was done in 6 cases (1 case of endolymphatic sac decompression and 5 cases of sac-mastoid shunting) and translabyrinth vestibular neurotomy was operated on 6 cases. RESULT: Complete relief from symptoms of vertigo occurred in the 6 cases through vestibular neurotomy and there were no recurrence in 11-13 years follow-up. Three of 6 cases with endolymphatic sac surgery had complete control of vertigo and were cured clinically. Symptoms of vertigo of the rest 3 cases were effectively controlled. CONCLUSION: Endolymphatic sac surgery and translabyrinth vestibular neurotomy are effective way for control of vertigo of patients with intractable Meniere's disease. Translabyrinth vestibular neurotomy are more effective for control of vertigo for appropriately selected patients.

Adult↗
PubMed1999

[With periosteal "sandwich" suturing and repairing septonasal perforation by nasal columella degloving].

OBJECTIVE: To recommend a new type of repairing septonasal peforation. METHOD: After a seagull's incision is made around the internal edges of anterior nares and the root of nasal columella, the mucoperiost of nasal septum and nasal bottom is widely dissected through the nasal columella degloving pathway. Then, relaxative incisions are made in bilateral mucoperiost at different directions and bilateral peforations are relaxative sutured at different levels respectively. Meanwhile, an autograft of tibil periost is fixed into nasal septum by the "sandwich" technique. Finally, both nasal cavities are carefully packed. RESULTS: Three cases of septonasal perforation were successfully repaired and have been followed up for 1-2 years respectivelly with no recurrence. CONCLUSION: The characteristics of this operation are: style rather fashionable, pathway rather wide, mucoperiost rather relaxed, suture rather firm and failing rather few.

Adult↗
PubMed1999

[Applied anatomy of anterior ethmoid relevant to endoscopic transnasal dacryocystorhinostomy].

OBJECTIVE: This study provided clinical guidance for the endoscopic transnasal dacryocystorhinostomy. METHOD: 16 adult cadavers were studied on the applied anatomy of between anterior ethmoid and fossa of lacrimal sac and the anatomic relationship between uncinate process and medial wall of orbit. RESULT: According to the anatomic relationship between anterior ethmoid sinus and fossa of lacrimal sac, the cells of anterior ethmoid sinus were classified into three typies, The results was that type I accounted for 31.2%, type II 50.0% type III 18.8%. CONCLUSION: CT scans should be performed to determine the anatomic relationships between fossa of lacrimal sac and anterior ethmoid and between uncinate process and medial wall of orbit before operation for patients with different typies of obstruction of nasocrimal duct, thus the proper bony opening was located during dacryocystorhinostomy.

Adult↗
PubMed1999

[The investigation of the audio-vestibular and oculomotor functions in people more than eighty years old].

OBJECTIVE: To investigate audio-vestibular and oculomotor functions of octogenarian. METHOD: The audition were measured with audiometry and auditory brainstem response. The semicrcular, oculomotor and balance functions were examinated by electronystagmography and posturography. RESULT: 1. The hearing abnormality of speech frequency were 84.1 percent by audiometry; 2. The abnormal rats of semicircular function and posturogram were 38.5% and 74.4% respectively. The body sway locus and velocity of octogenarians have increased as compared with the group of 60 years old in the posturography; 3. The latency of saccade was prolonged and total hearmonic distortion of pusuit was increased than that of 60 years old in the oculomotor test. CONCLUSION: The easily falling of octogenarians may be related to disturbing of semicircular oculomotor and equilibrational functions.

Age Factors↗
PubMed1999

[Analysis of the isomers of dihydroxybenzenes by micellar electrokinetic capillary chromatography with on-column amperometric detection at carbon-fiber microelectrode].

The effects of the concentrations of beta-cyclodextrin(CD) in electrolyte on the cyclic voltammetric properties of o-, m-, p-dihydroxybenzenes at carbon-fiber microelectrode were studied. The inclusion between o-, m-, p-dihydroxybenzenes and beta-CD was investigated based on the molecular structures and experimental results. The study showed that the order of the inclusion interaction, from strong to weak, between dihydroxybenzenes and beta-CD, was m-, o- and p-dihydroxybenzenes. The effects of the concentrations of NH4Cl, SDS and beta-CD, and the pH values of the electrophoretic buffer on the migration time of o, m, p-dihydroxybenzenes were investigated. The assay of o, m, p-dihydroxybenzenes by micellar electrokinetic capillary chromatography with on-column amperometric detection at carbon-fiber microelectrode was developed. The recovery ranged from 98% to 103%.

Carbon↗
PubMed1999

Supercritical fluid CO2 extraction of colchicine from colchicine Autumnele liliaceae.

Colchicine was successfully extracted from the corms of colchicine autumnele Liliaceae using supercritical fluid (SF) CO2. The pressure range used in the experiments was 20-40 MPa and the temperature was 40 degrees C. Being its high molecular polar, colchicine or other alkaloids are not easy to be extracted by SF CO2. In order to increase the mass transfer from the sample matrix to SF, different presoakers (such as methanol, ethanol, acetone etc.) were employed. Among the selected pre-soakers, best results were obtained with ethanol both in the aspects of yield and selectivity. At 35 MPa, 40 degrees C and with ethanol as pre-soaker, the yield was 1.8 mg/g, and the colchicine could be almost completely extracted from the sample matrix. The average concentration increased from 0.18% in natural sample to 6.92% in extract with SFE processing only once under the given conditions. The comparison of liquid ethanol extraction (LEE) and SFE showed that SFE is greatly superior to LEE in colchicine separation with SFE not only higher yield and selectivity but also a quick, safe and non-toxic method were obtained in colchicine extraction.

Carbon Dioxide↗
PubMed1999

[Determination of risperidone and 9-hydroxyrisperidone in plasma by high performance liquid chromatography].

A reversed-phase HPLC method for the determination of risperidone and 9-hydroxyrisperidone in plasma was established. Risperidone and 9-hydroxyrisperidone can be separated on a Zorbax ODS C18 column with a mobile phase of MeOH-water-ammonium acetate (mol/L)-ammonia water(3 mol/L) (300:50:3:1, volume ratios) and detected at 280 nm. The flow rate was 0.8 mL/min. The linear range was 2-600 micrograms/L, r = 0.996 for risperidone, and 2-800 micrograms/L, r = 0.998 for 9-hydroxyrisperidone. The average recovery was (98.2 +/- 3.5)% for risperidone, and (97.8 +/- 3.8)% for 9-hydorxyrisperidone. The intra-day and inter-day coefficients of variation were 4.12% and 4.83% for risperidone respectively, 4.28% and 4.81% for 9-hydroxyrisperidone respectively. The method has been used to determine risperidone and 9-hydroxyrisperidone mass concentration in patient plasma. The data obtained showed that the sensitivity and selectivity of this method were adequate for drug monitoring in clinical research.

Antipsychotic Agents↗
PubMed1999

[Strain screening and fermentation conditions of a novel heparinase-producing strain].

The novel heparinase-producing bacterial strain Corynebacterium sp. was screened and isolated from soil. The optimum medium composition is (g/L): Trypticase 20, NaCl 1, K2HPO4 2.5, MgSO4 0.5, Heparin 2, maltose 20, pH 6.5. The optimum growth temperature was 27 degrees C while, maximum enzyme production was achieved at temperature 31 degrees C. When cultured at a rotating shaker at 30 degrees C for 24 hours, 200 r/min, 40 mL medium in 500 mL flask, the Production of heparinase reached 1700 u/L.

Corynebacterium↗
PubMed1999

[Culture conditions of engineered strain of L-asparaginase and the recombinant plasmid stability].

The growth curves of engineered strain JM105(pASN) were different in LB and M-3 media. The expression level and activity of L-asparaginase were affected apparently by both biomass and induction time. Glucose repression of production of L-asparaginase was found. The stability of the recombinant plasmid pASN in different host strains and in LB and M-3 media was determined. After cultivation inLB broth and M-3 media at 30 degrees C for more than 50 generations without antibiotic selection, then induced at 42 degrees C for up to 5 h, the engineered strains were proved to be stable, except for DHA alpha (pASN).

Asparaginase↗
PubMed1999

[Screening of acidic xylanase producing strain and studies on its enzyme production conditions].

From 150 fungal strains, the authors found 8 strains contained mainly of xylanase activity over 100 U/mL in which the No. 149 strain was the highest xylanase producer. Which tentatively identified as Aspergillas niger. The appropriate medium composition was as follows: wheat bran hemicellulose 4%; NaNO3 1%; wheat bran 1% prepared in Mandels nutritional solution without (NH4)2SO4 and urea. After cultivated in shake-flask at 28 degrees C-32 degrees C for 60 h, the activity reached the highest value of 357.2 U/mL. The optimum pH of xylanase was 4.6 and it was stable at pH3-11. The fermented broth of strain 149 contained in addition to xylanase (relative activity 100) also included amylase(1.8), mannanase(0.98), beta-xylosidase(0.94) and cellulase(0.17).

Aspergillus niger↗
PubMed1999

Establishment of immunoglobulin M(IgM)-immunosorbent agglutination assay (ISAGA) for diagnosis of toxoplasmosis.

AIM: To establish an immunosorbent agglutination assay (ISAGA) for detection of IgM antibodies against Toxoplasma gondii. METHODS: In the ISAGA, wells of microtiter plates were coated with anti-human IgM antibodies and sealed with 1% bovine serum albumin. After the test sera were added and incubated, the plates were washed, T. gondii tachyzoite antigen suspension was added, and incubated overnight at 37 degrees C. The ISAGA results were evaluated by comparing with those detected by Danish ISAGA and ELISA and those detected by slide enzyme immunoassay (S-EIA). RESULTS: Forty-four sera from Danish pregnant women were tested by the IgM-ISAGA, 41(93.2%) were consistent with the Danish results. Sixty-seven sera from Danish and Shanghai pregnant women were detected by IgM-IgM-ISAGA and S-EIA, the total consistency rate was 92.5%. A significant correlation was found between the titers of the ISAGA and S-EIA, with a Pearson correlation coefficient of 0.589(P < 0.001). The titers of ISAGA were eighteen times higher than those of S-EIA. This method enables the detection of IgM antibodies as low as approximately 0.08 IU/ml. CONCLUSION: The IgM-ISAGA is therefore sensitive, specific, easy to perform, and is useful for mass screening and diagnosing recent Toxoplasma infection or reactivation.

Agglutination Tests↗
PubMed1999

[Protective effects of leishmanial antigens against Leishmania infantum infection in Lagurus lagurus].

AIM: To determine the protective effect of leishmanial surface antigens against experimental visceral leishmaniasis in Lagurus lagurus caused by Leishmania infantum. METHODS: Recombinant surface protein (rGP63) and lipophosphoglycan (LPG) of Leishmania were used with Corinebacterium parum vaccine as ajuvant to immunize Lagurus lagurus against a challenge with virulent strain of Leishmania infantum. The efficacy of immunoprotection was observed. RESULTS: When challenged with up to 2 x 10(7) promastigotes, the number of LD on the liver printing sections in the rGP63 + LPG + CP immunised animals was significantly decreased, the parasite reduction rate being 89.79%. LPG + CP gave a parasite reduction rate of 60.6% and rGP63/beta-galactosidase fusion protein + CP showed a parasite reduction rate of 42.45%. Purified rGP63 showed no protection. Immunization with rGP63 + LPG + CP followed by challenge inifection with 1 x 10(6), 5 x 10(6) and 1 x 10(7) promastigotes also showed significantly reduced infection rates. CONCLUSION: A combination of rGP63 + LPG + CP antigens could provide significant immunoprotection against L. infantum challenge in L. lagurus.

Animals↗
PubMed1999

[Field application of oral artesunate for preventing Schistosoma japonicum infection].

AIM: To assess the preventive effect of oral artesunate against S. japonicum infection. METHODS: Residents in two pilots in the schistosomiasis endemic regions, 562 cases in Yanghe pilot, Wangjiang County and 218 cases in Shashan pilot, Guichi City, Anhui Province, were selected for this study. The residents were divided into two groups. Group I received artesunate 6 mg/kg once every 2 weeks for 4 times 2 wk after contacting with infested water from July to September in 1997. Group II received the same dosage of placebo at the corresponding times. Four weeks after the last administration, stool examination using hatching method and Kato's method was conducted to evaluate the effect. RESULTS: In Yanghe pilot, 2 cases were hatching positive in the artesunate-treated group with an infection rate of 0.7% (2/273), while 11 cases were stool positive in placebo group with an infection rate of 3.8% (11/289) and a mean EPG of 26.40 +/- 1.49. In Shashan pilot, all cases in artesunate-treated group were stool negative, while 7 cases were stool positive in the placebo group with an infection rate of 6.3% (7/111), and a mean EPG of 14.23 +/- 2.14. The protection rate of artesunate was 80.9% and 100%, respectively, in the two pilots. CONCLUSION: Artesunate can protect the residents from S. japonicum infection effectively.

Administration, Oral↗
PubMed1999

[In vivo anti-fecundity effect of recombinant Sjc26 GST against Schistosoma japonicum in immunized mice].

AIM: To observe the anti-fecundity effect of recombinant Sjc26 GST against Schistosoma japonicum and its mechanism. METHODS: Male ICR mice were immunized with rSjc26 GST. Five days after final injection, mice of the immunization and control groups were challenged with 40 +/- 1 S. japonicum cercariae. All mice were sacrified at 6 weeks after challenge. RESULTS: The worm reduction rate was 30.0%, and the egg reduction rates in the liver and in the spleen were 57.1% and 79.9%, respectively. Inhibition of the vitelline gland and testis was also observed by transmission electron microscopy. The number of vitelline globes, vitelline droplets and lipid droplets in the cytoplasm of vitelline cell and the number of lipid droplets in the supporting cells and the number of spermatids in the testis were apparently reduced. CONCLUSION: The damage of the main reproductive organs of Schistosoma japonicum was one of the factors responsible for rSjc26 GST-bound anti-fecundity action.

Animals↗