[Effects of mechanical ventilation and controlled spontaneous respiration on pulmonary function during short duration of general anesthesia with tracheal intubation].

OBJECTIVE: To evaluate the effects of mechanical ventilation on pulmonary function during short duration of general anesthesia with tracheal intubation, and assess the safety of controlled spontaneous respiration during general anesthesia. METHODS: Fifty-three adult patients (aged 18-55 years, ASA physical status I-II) scheduled for elective unilateral tympanoplasty were randomly assigned into mechanical ventilation group (group M, n=28) and spontaneous respiration group (group S, n=25). Anesthesia induction was performed in group M with intravenous propofol (2 mg/kg), fentanyl (3 microg0.05). The pH and SpO(2) [ (97.9-/+1.00)% at the lowest] and PaO(2) in group S were significantly lower and the PaCO(2) was higher than those in group M (P<0.05). In group S, the pH values were 7.274-/+0.025 and 7.331-/+0.039, PaCO(2) values were 60-/+6 and 53-/+5 mmHg, and PETCO(2) values were 53-/+ 6 and 48-/+7 mmHg, and the PaO(2) values were 143-/+37 and 165-/+49 mmHg immediately and 150 min after the intubation, respectively. These values were considered safe under the concept of permissive hypercapnia. No significant differences were found in the P(A-a)DO(2), RI, VD/VT and TFC between or within the two groups (P>0.05), nor were moving, bucking, swallowing and awareness recorded during the surgical procedures. CONCLUSION: In essentially normal lungs, short-term mechanical ventilation during general anesthesia with tracheal intubation does not damage the lung functions, and spontaneous respiration can offer sufficient oxygen supply without causing harmful carbon dioxide retention.

[Studies on the chemical constituents of ethyl acetate extract from the roots of Actinidia chrysantha].

OBJECTIVE: To study the chemical constituents of ethyl acetate extract from the roots of Actinidia chrysantha. METHODS: Chromatographic methods were used to isolate the compounds from ethyl acetate extract from the roots of Actinidia chrysantha and chemical and spectral methods were used to elucidate the structures of the isolated compounds. RESULTS: Five compounds were identified as stigmast-3, 6-dione (I), beta-sitosterol (II), ursolicacid (III), beta-daucosterol (IV), 2alpha, 3beta, 23-triol-12-en-28-ursolic acid (V). CONCLUSION: Those compounds are obtained from the plant for the first time.

[Anti-tumor mechanism of active components from extract of Actinidia rufa root].

OBJECTIVE: To observe effect and mechanism of n-Butanol lysate of alcohol extracts from Actinidia rufa root (monomer of R6,R8). METHOD: Tunel, Wright's stain with Giemsa's stain dyeing, and Hoechst 33258-PI double dyeing assay were used to detect the apoptosis of SGC7901 tumor cells treated with R6, R8. The SGC7901 tumor cells were randomly divided into control group and two treatment groups administered 0.05 g x L(-1) R6, R8, respectively, for 72 h). FCM assay was used to detect the apoptosis. Agarose electrophoresis assay was used to detect DNA strand break of tumor cells and reveal anti-tumor action mechanism. RESULT: The apoptosis percentage of the tumor cell in 24 h, 48 h, 72 h was (17.08 +/- 2.78)% , (29.68 +/- 2.96)%, (52.46 +/- 3.81)%; (14.75 +/- 2.14)%, (27.35 +/- 3.79)%, (45.64 +/- 5.24)%, respectively, for the treatment group, significantly higher than that in the control group (1.94 +/- 1.55)%, (2.78 +/- 1.84)%, (11.8 +/- 2.79)% (P < 0.01) by tunnel assay. Wright's stain with Giemsa's stain dyeing assay, Hoechst 33258-PI and FCM double dyeing assay showed same action. R6 and R8 had the effect of inducing the DNA histogram of tumor cells (P < 0.01). CONCLUSION: The anti-tumor mechanisms may be associated with inducing the injury of DNA and stimulating apoptosis.

[Loudness growth functions between children with normal hearing and sensorineural hearing loss by the modified Contour test].

OBJECTIVE: To compare the loudness growth of normal hearing children and children with sensorineural hearing loss (SNHL) by the modified Contour test. METHODS: The loudness growth function were obtained in 26 ears with normal hearing and 25 ears with SNHL using the modified Contour test. Retesting were carried out 2 or 3 weeks later after the initial test. The results were analyzed by the univariate analysis of variance. RESULTS: There was significant difference in loudness growth between normal hearing group and groups with SNHL of different degrees (F = 1368.32, P < 0.001), and also between different loudness categories (F = 682.21, P < 0.001). Large differences were observed in the dynamic range between normal hearing children and children with sensorineural hearing loss (F = 214.26, P < 0.001). The following results were found in the loudness growth in children with SNHL: the more serious the hearing loss was, the more rapid the loudness growth and the smaller the dynamic range. The test-retest reliability of loudness growth function obtained in normal hearing and hearing-impaired group was highly correlated. The results of modified contour test showed good reliability. CONCLUSIONS: When fitting hearing aids for a child the result of individual loudness growth should be obtained as possible as it could be drawn to reach the best listening saturation for the child. The modified contour test was a vivid and easy-to-do test for children, also with good reliability. In order to fit hearing aids properly for children, it was worth applying the modified contour test in clinic.

[Relationship between the content of fibrinogen in middle ear effusion and the effect of treatment on secretory otitis media].

OBJECTIVE: To study the relationship between the fibrinogen content in middle ear effusion (MEE) and the protracted inflammation of secretory otitis media (SOM) and to explore the possible mechanism of batroxobin in treatment of SOM. METHODS: The fibrinogen content of middle ear effusion from 156 patients with SOM was investigated with concretion technique at different stages. After two times punctuation of tympanum, the recurrence patients were randomly divided into two groups: batroxobin and dexamethasone group, and 0.5 ml (2 BU/ml) batroxobin or dexamethasone (2 mg/ml) was injected into middle ear cavity. The therapeutic effects were investigated. RESULTS: The concentration of fibrinogen in the recurrence group of SOM patients was higher than that in the cured group, and even higher in the second recurrence group than in the first recurrence group (P < 0.01). There was significantly different (P < 0.001) in the therapeutic efficacy between the batroxobin group (91.6%) and the dexamethasone group (62. 5%); the difference of the fibrinogen content in MEE and air conduction of pure tone audiometry at frequencies (0.5, 1.0, 2.0 kHz) between the two groups after treatment were also significant (P < 0.01). CONCLUSIONS: Fibrinogen may play a significant role in the occurrence and development of secretory otitis media. Batroxobin had better therapeutic effect on SOM than dexamethasone. The mechanism of batroxobin in the treatment of SOM may be that the batroxobin can relief the depressant effect of fibrinogen on surface active agents of the Eustachian tube and prevent the fibrinogen from turning into insoluble fibrin polymer by means of fibrinolysis.