Biomedical subjects

Y Guo

Publications and source records attributed to Y Guo.

At least 127 records · Page 7Linked to original sources

PubMed2001

[Realization of a new segmental bioelectrical impedance method for assessing body composition: correlation analysis of human body parameters].

The method of segmental bioelectrical impedance analysis for assessing body composition requires measurement of segmental lengths and cross-sectional areas; thus its complexity is increased. This paper reports the correlation analysis of human body parameters and the linear regressions for predicting segmental parameters by use of gender, height and weight. Accordingly, segmental impedance analysis is simplified.

Adolescent↗

PubMed2001

Comparison of the effects of two types of intraocular lens.

OBJECTIVE: To evaluate the effectiveness and safety of implantation of flexible open-loop anterior chamber intraocular lens (FOAC-IOLs) and scleral fixated posterior chamber intraocular lens (PC-IOLs). METHODS: Sixty-eight eyes of 68 patients with implanted intraocular lenses in the absence of posterior capsular support were reviewed retrospectively. According to the type of intraocular lens, patients were classified into two groups. In group I (30 eyes), FOAC-IOLs was implanted primarily or secondarily. In group II (38 eyes), scleral fixated PC-IOLs was implanted primarily or secondarily. By gonioscopy and ultrasound biomicroscopy (UBM), accurate positions of IOLs' haptics and the relationship between the haptics and surrounding tissues were observed postoperatively and used to evaluate the influence of the two types of IOLs on ocular anterior segments. Follow-up was 6 to 20 months. RESULTS: Best corrected visual acuity of 20/40 or better was achieved in 27 eyes (90.0%) in group I, and 35 eyes (92.1%) in group II and the difference was not statistically significant (P > 0.05). In group I, 23 eyes (76.7%) had a total of 40 complications, while 13 eyes (34.2%) had 19 complications in group II (P < 0.05). Gonioscopy and ultrasound biomicroscopy showed that in group I, all haptics of IOLs contacted with the iris completely and compressed the iris to different degrees, sometimes causing the anterior chamber angles to widen. Anterior synechia of the iris was caused by the haptics of FOAC-IOLs in 12 eyes. Among the 60 IOLs haptics, 39 foot plates of the haptics were properly fixed at the ciliary band; 21 haptics (12 eyes) penetrated through the iris into the stroma of the ciliary body with accompanying recurrent uveitis. In group II, among the 76 IOLs haptics, 52 were adequately fixed in the ciliary sulcus regions, and 8 (8 eyes) were placed below the iris, causing goniosynechia. This type of angle closure was localized, with an open angle on each side of the haptics. The remaining 16 haptics were fixed onto the ciliary crown. CONCLUSIONS: The current sutured mode of scleral fixated PC-IOLs can not ensure that IOLs haptics are placed in the ciliary sulcus. The haptics of FOAC-IOLs compress the iris and may penetrate through the iris into the stroma of the ciliary body. This can cause peripheral iris anterior synechia and chronic recurrent uveitis. The implantation of scleral fixated PC-IOLs is safer and shows better effects than that of FOAC-IOLs.

Aged↗

PubMed2001

[The relationship between eosinophils, activated T lymphocyte, leukotreine and the exercise-induced asthma].

OBJECTIVE: To explore the relationship between eosinophils, T lymphocyte, leukotreine (LT) and exercise-induced asthma (EIA). METHODS: In 32 asthmatic patients (13 with EIA and 19 asthmatic without EIA) and 8 normal persons, serum eosinophil cationic protein (ECP) and actived T lymphocyte (CD(25)(+)%) in peripheral blood were measured at the time before and 10, 60 minutes after exercise testing. The maximum minute ventilation (V(E)) were also measured. Another 22 non-smoking asthmatic patients with EIA and 10 normal subjects were enrolled for measuring urinary leukotriene E(4) levels before and 2 hours after exercise. EIA patients received zafirlukast 20 mg twice a day for three days. Standardized exercise challenge were performed after 72 hours of medication. RESULTS: There was a linear relationship between ECP, CD(25)(+)% and the forced expiratory volume in one second (FEV(1)) in asthmatic group (r = -0.79 and -0.61 all P < 0.01). Expressions of IL-4 mRNA, IL-5 mRNA CD(25)(+)% and serum ECP levels showed no significant difference at all testing points between two asthmatic groups, meanwhile, V(E) also showed no difference among three groups. Urinary LTE(4) levels in EIA group increased significantly two hours after exercise. Zafirlukast significantly reduced AUC(0 approximately 60 min) and the percentage of maximum fall in FEV(1) and accelerated the falling FEV(1) to return to pre-exercise baseline. CONCLUSIONS: Hyperventilation during exercise may not be the cause leading to EIA, neither did the activation of T lymphocytes, IL-4 and IL-5 gene expression nor ECP. Leukotriene may play an important role in the pathogenesis of EIA.

Adult↗

PubMed2001

[Anti-tumor effect of E1B55kDa-deleted adenovirus on human hepatocellular carcinoma cell lines].

OBJECTIVE: To investigate the in vitro and in vivo anti-tumoral effect of E1B55kDa-deleted adenovirus (dl1520) on human hepatocellular carcinoma (HCC) cell lines. METHODS: Human HCC cell lines with different p53 genotypes were infected with dl1520. Four days after infection, the percentage of survival cells was determined by colorimetric assay. RT-polymerase chain reaction (PCR) was used to examine alterations of p53 and p21Waf-1 expression. Adenovirus hexon gene expression was applied to prove the presence of adenovirus infections. Effects on vivo anti-tumor dl1520 were examined with intra-tumor injection of dl1520 in the SCID mice. RESULTS: After the infection, the p53-null HCC cell line, Hep3B was most vulnerable to dl1520 induced cytotoxic effect with a cell death rate of more than 60%. Whereas, less than 20% PLC/PRF/5 (p53-mutant) and HepG2 (p53-wild type) HCC cell lines were killed. The expression of p53 and p21Waf-1 was considerably enhanced after the dl1520 infection in HepG2. The intra-tumor injection of dl1520 significantly reduced the tumor growth in Hep3B xenografts. In contrast, no obvious tumor repression was observed in HepG2 and PLC/PRF/5 xenografts. CONCLUSION: dl1520 selectively kills the p53-null hepatocellular carcinoma, showing potential application for cancer treatment.

Adenovirus E1B Proteins↗

PubMed2001

[The Immunophenotypical features of t (8; 21) (q22; q22) acute myeloid leukemia].

OBJECTIVE: To study the predictive value of immunophenotypical features in t (8; 21) (q22; q22) acute myeloid leukemia (AML). METHODS: Morphological/cytochemical, flow cytometric immunophenotyping, cytogenetic analyses (MIC) and RT-PCR were performed in 294 previously untreated AML. RESULTS: (1) In 294 AML patients, t (8; 21) AML were 21.8% (64); in AML-M(2), t (8; 21) AML were 54.7%; and in t (8; 21) AML, AML-M(2) were 81.3%. (2) Compared with control group, CD(19) and CD(34) expressions were higher, and CD(33) expression was lower (P < 0.001) in t (8; 21) AML. (3) If the cut-off value of CD(19) positive was >or= 20%, CD(19) positive rate was 13.6% (40/294) in AML, and 50% (32/64) and 3.5% (8/230) (P < 0.001) in t (8; 21) AML and control group. (4) CD(19)(+) and/or CD(34)(+) t (8; 21) AML accounted for 90.6% (58/64) of t (8; 21) AML and CD(19)(-)/CD(34)(-) for 9.6% (6/64). CONCLUSION: In t (8; 21) AML, especially M(2)/t (8; 21), CD(19) and CD(34) expressions were high. CD(19) was one of predictive markers of t (8; 21) AML.

Adolescent↗

PubMed2001

Serum antioxidant status of civil aircrew.

Objective. To study the serum antioxidant status in civil aircrew members who had more than 4000 h of cumulative flight hours, therefore exposed to a higher dose of cosmic radiation comparing to the dose received by ground residents. Method. Differences in the serum levels of total antioxidant capacity (TAOC), superoxide dismutase (SOD) and malondialdehyde (MDA) were investigated in 230 crew members, 37 local ground residents in Xinjiang, and 37 ground residents in Tianjin. Result. Significantly higher levels of all the three serum indexes were found in civil aircrew members. Serum levels of TAOC and SOD were higher in Xinjiang than in Tianjin ground residents, although no difference was found for MDA. Positive correlations were observed among the three serum indexes in this study. Conclusion. The elevated serum level of MDA in civil aircrew members deserves a proper attention by health care policy makers.

Adult↗

PubMed2001

[A discussion on diagnosis and typing of viral hepatitis].

OBJECTIVE: To bring forward a suggestion about clinical diagnostic standard and clinical typing for chronic and severe hepatitis. METHODS: To make a comprehensive study on clinical features and pathology of 895 cases of severe and chronic hepatitis, liver cirrhosis after hepatitis based on the viral prevention and control plan laid down in 1995. RESULTS: The chronic hepatitis can still be divided into mild, moderate and severe types clinically, but the PTA should be changed for normol-71, 70-61, 60-51, the A/G value for normal, 1.5-1.3, 1.2-1.0 respectively. ALT, BIL, alpha-globulin are kept unchanged. The albumin value can be cut out from the reference indexes of clinical typing for chronic hepatitis. Acute severe hepatitis can be divided into early stage (taking edema as the main type) and late stage (taking necrosis as the main type); subacute severe hepatitis can be divided into ascite type, coma type and mixed type; if those lacking of coma and ascite with PTA about 60%. 50% can be treated as earlier stage. Subacute and chronic severe hepatitis still can be divided into early, middle and late stages. The disease course of subacute severe hepatitis may prolong to six months. Chronic severe hepatitis can be divided into type B (typical chronic hepatitis type) type C (liver cirrhosis type) and type c (acute liver failure type developed from chronic hepatitis and viral carriers). CONCLUSIONS: The original procedure of 1995 are feasible on the whole.

Factor XI↗

PubMed2001

[Purification of conjugated bilirubin from human urine].

OBJECTIVES: To develop a simple, practical method with fine yield and purity for separating conjugated bilirubin(Bc) from a sustainable and facile material in order that it could serve as a calibrator for total and direct bilirubin determination. METHODS: Isolating Bc from urine of patients with obstructive jaundice by CHCl3: CH3CH2OH(1:1, V/V) followed by CNBr activated Sepharose 4B-HAS affinity chromatography, we analyzed the products by the use of Doumas J-G diazo method and HPLC, respectively. RESULTS: Determined by J-G diazo method, the crude product extracted by CHCl3: CH3CH2OH(1:1, V/V) yields 90.2 +/- 5.4%(n = 3) of urine Bc, the ratio of Bc to total dry weight being 67.9 +/- 6.4%(n = 3). The final product purified by affinity chromatography with the ratio of separation of 1.5, 1.737 and analyzed by HPLC has the yield of 46.9% and purity of 94.7%(BDG of 76.2%, BMG of 18.5%). CONCLUSION: The above data demonstrate that urine conjugated bilirubin can be successfully purified by CHCl3: CH3CH2OH extraction followed by Sephrose-HSA affinity chromatography with sufficient purity and output.

Bilirubin↗

PubMed2001

[Effects of selective attention and contralateral acoustic stimulation on latency of distortion product otoacoustic emissions].

OBJECTIVE: To investigate the effects of selective attention and contralateral acoustic stimulation on latency of distortion product otoacoustic emissions. METHOD: Latency of DPOAE was recorded in 30 ears of 15 normal subjects with and without visual attention task, contralateral acoustic stimulation and combination of both forms of stimulus. RESULT: No significant change was observed in three form of stimulus. CONCLUSION: The effects of selective attention and contralateral acoustic stimulation on latency of DPOAE have to be further studied.

Acoustic Stimulation↗

PubMed2001

[Isolation of outer hair cells from varying turns of the guinea-pig cochlea].

OBJECTIVE: To probe the method of isolating outer hair cells (OHC) from each of four turns of the guinea-pig cochlea. METHOD: From eight guinea pigs the organ of Corti from each of four turns of the cochlea were dissected, and then treated using enzyme. RESULT: A fair amount of living OHCs from each of four turns were obtained. The length of OHCs from each of four turns were 23.81, 34.50, 60.48 and 71.37 microns. CONCLUSION: The key to success in isolating OHCs from each of four turns of the cochlea is to know very well the anatomical characteristics of each of four turns of the cochlea and be operated in accordance with normal rules.

Animals↗

PubMed2001

[Application of CT virtual bronchoscope in foreign-body in children's bronchus].

OBJECTIVE: To evaluate the clinical application of CT virtual bronchoscope in foreign-body in bonchus. METHOD: The CT virtual bronchoscope were used in 21 cases with foreign-body in bronchus, all the images and reports were compared with the actual bronchoscopy. RESULT: The reports and images of CT virtual bronchoscope are very agreed with that of actual bronchoscopy. CONCLUSION: CT virtual bronchoscope is a very good complemental method in preoperative diagnosis of foreign-body in bronchus.

Bronchi↗

PubMed2001

[Phacoemulsification in patients with cataract and overfiltering bleb after antiglaucoma surgery].

PURPOSE: To evaluate the effect of phacoemulsification in patients with cataract, overfiltering bleb, and low-tension after antiglaucoma surgery. METHODS: Phacoemulsification and implantation of a foldable intraocular len was performed in six patients(7 eyes) with overfiltering bleb, low-tension, and cataract. The complications, blebs, intraocular pressures(IOP), and visual acuity were observed postoperatively. RESULTS: No severe complication was found. The overfiltering blebs constricted and their walls became thicker three months after the operation. The visual acuity and IOP were improved (P < 0.05). CONCLUSION: Phacoemulsification may be another way to treat the patients with cataract and overfiltering bleb, low-tension after antiglaucoma surgery.

Aged↗

PubMed2001

[Inhibitory effects of benzoisoselenothiazolidone sulfonamide derivatives on cyclooxygenase].

AIM: To study the inhibitory effects of benzisoselenothiazolidone sulfonamide derivatives on cyclooxygenase. METHODS: 6-Keto-PGF1 alpha and PGE2 were assayed by radioimmunoassay (RIA) method; mRNA expression of COX-1 and COX-2 were assayed by reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: Compound A [N-4-(4-methoxyphenyl-aminosulfonyl)-benziososelenothiazolidone] and B [N-4-(4-fluorophenyl-aminosulfonyl)-benzoisoselenothiazolidone] were two benzoisoselenothiazolidone sulfonamide derivatives, which can inhibit COX activity with IC50 of 1.5 x 10(-8) mol.L-1 and 5.0 x 10(-8) mol.L-1 for COX-2, as well as IC50 of 1.5 x 10(-5) mol.L-1 and 2.8 x 10(-5) mol.L-1 for COX-1. The ratio of IC50 COX-1/IC50 COX-2 of compound A and B are 1,000 and 560, respectively. They both can inhibit COX-2 mRNA expression in cultured rat peritoneal macrophages stimulated with LPS (1 microgram.mL-1), and have no effect on COX-1 mRNA expressions. CONCLUSION: Compound A and B, two benzoisoselenothiazolidone sulfonamide derivatives, both are selective inhibitory agents of COX-2, and possess inhibitory effects on 5-lipoxygenase and cyclooxygenase.

Animals↗

PubMed2001

[Inhibitory effects of indomethacin and meloxicam on NF-kappa B in mouse peritoneal macrophages].

AIM: To study the inhibitory effects of indomethacin and meloxicam on NF-kappa B from lipopolysaccharide (LPS) stimulated peritoneal macrophages of mice. METHODS: NF-kappa B was measured with the method of electrophoretic mobility shift assay (EMSA). RESULTS: After induction by LPS at the concentrations of 1 and 3 micrograms.mL-1, the NF-kappa B content of the mouse peritoneal macrophages increased markedly. Indomethacin and meloxicam, at the concentrations of 10(-7)-10(-5) mol.L-1, decreased the activation of NF-kappa B at the concentrations of 1 and 3 micrograms.mL-1 in activated mouse peritoneal macrophages induced with LPS at the concentrations of 1 and 3 micrograms.mL-1. CONCLUSION: The inhibitory effects of indomethacin and meloxicam on NF-kappa B activation may be one of their mechanisms of antiinflammatory actions.

Animals↗

PubMed2001

[Inhibitory effects of hydrocortisone on human polymorphonuclear leukocyte adhesion to human synovial cell].

AIM: To investigate the inhibitory effects of hydrocortisone on human polymorphonuclear leukocyte (PMN) adhesion to human synovial cell (HSC), and to explore its mechanism. METHODS: MTT colorimetry was used to determine the adhesion effect of PMN to HSC. Cell-ELISA and RT-PCR methods were used to determine the expression of adhesion molecular ICAM-1 and VCAM-1. EMSA method was also used to observe the activity of nucleus transcription factor-kappa B (NF-kappa B). RESULTS: Hydrocortisone inhibited TNF-alpha (50 U.mL-1 for 12 hours) and IL-1 beta (50 U.mL-1 for 12 hours)-induced adhesion of PMN to HSC (IC50 2.05 x 10(-6) mol.L-1 and 2.13 x 10(-7) mol.L-1, respectively) in a concentration-dependent manner. Adhesion molecular VCAM-1 and ICAM-1 protein and mRNA (rather than ICAM-1) expression in HSC induced by TNF-alpha (50 U.mL-1) were inhibited significantly by hydrocortisone at 1 x 10(-6)-10(-5) mol.L-1. The activity of NF-kappa B was also extensively inhibited by hydrocortisone at 1 x 10(-6)-10(-5) mol.L-1. CONCLUSION: Hydrocortisone inhibited TNF-alpha-stimulated PMN-HSC adhesion, and expression of VCAM-1 by suppressing the activity of NF-kappa B.

Adult↗

PubMed2001

[Inhibitory effects of isorhapotigenin on IL-8 production and mRNA expression induced with TNF alpha in normal human synovial cells].

AIM: To study the effects of isorhapotigenin (Iso) on interleukin-8 (IL-8) production and mRNA expression in normal human synovial cells (HSC) induced with TNF alpha. METHODS: IL-8 were assayed with RIA method. The mRNA expression of IL-8 was detected by RT-PCR method. RESULTS: It was shown that TNF alpha at concentrations of 0.05 to 0.5 U.mL-1 for 24 h significantly increased IL-8 production. The expression of IL-8 mRNA was also promoted by TNF alpha (0.25 U.mL-1) for 6 h. Iso at the concentrations of 1 x 10(-6) mol.L-1 to 1 x 10(-5) mol.L-1 showed inhibitory effects on IL-8 production induced with TNF alpha (0.25 U.mL-1). The further study indicated that Iso at the concentrations of 1 x 10(-6) mol.L-1 to 1 x 10(-5) mol.L-1 inhibited IL-8 mRNA expression in HSC induced with TNF alpha (0.25 U.mL-1). CONCLUSION: TNF alpha promoted IL-8 production and mRNA expression in HSC. Iso inhibited IL-8 production and mRNA expression induced by TNF alpha (0.25 U.mL-1). This might be one of the anti-inflammatory mechanisms of Iso.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2001

[Experimental study on polyaspartic acid inhibition of gentamicin-induced generation of reactive oxygen species in guinea pig cochlea].

OBJECTIVE: To observe the polyaspartic acid(PAA) inhibition of gentamicin-induced reactive oxygen species generation in cochlea of guinea pig and to investigate the protective mechanism of polyaspartic acid on gentamicin ototoxicity. METHODS: Eighty-eight guinea pigs were divided randomly into four groups (GM, PAA + GM, PAA, and Saline). Gentamicin-induced reactive oxygen species (ROS) formation in cochlear tissue was detected directly with electron paramagnetic resonance (EPR) spectrometry at 1st, 5th and 10th day after administration of the drugs. At the same time, ABRs of guinea pigs were recorded and ultrastructural changes of lysosomes in the cochlear hair cells were observed with transmission electron microscopy. RESULTS: 1. At 1st day after administration of PAA and GM, there was some increase in EPR spectrometry in group GM and PAA + GM, There was no significant difference of ABR thresholds and ultrastructural changes of lysosomes in the cochlear hair cells among four groups(P > 0.05). 2. At 5th day, there was significant increase in of EPR spectrometry in group I (37.74 +/- 4.10, P < 0.01). At 10th day after administration of PAA and GM, there was no significant difference in EPR spectrometry among four groups (P > 0.05). In GM group, ultrastructural changes of lysosomes beneath cuticular plate of cochlear hair cells were more significant at 10th day than those at 5th day, including the increased number and volume of lysosome. In group GM, the longer the gentamicin administrated, the more significant increase in ABR thresholds had been noted. CONCLUSION: PAA significantly inhibits gentamicin-induced reactive oxygen species generation in cochlea of guinea pig, which showed that PAA has protective effect on gentamicin-ototoxicity and -phospholipidosis in guinea pigs.

Animals↗

PubMed2001

[Nasal/nasopharyngeal T/NK-cell lymphomas with evident angiogenic activity].

OBJECTIVE: To search the difference of the angiogenic activity between T/NK-cell lymphomas and B-cell lymphomas. METHODS: The T/NK-cell was stained immunohistochemically by CD56 and CD45 RO, the B-cell was by CD20, the microvessel endothelium was by CD34. Sixty-one cases were studied to examine the immunophenotype and to estimate the intratumoral microvessel density (iMVD). RESULTS: Forty in 61 cases (65.6%) expressed the immunophenotype of both T-cell and Natural Killer cell, were diagnosed T/NK-cell lymphomas. Fifteen in 61 cases (24.6%) expressed the immunophenotype of B-cell. There was a significant difference in incidence between the two types of lymphomas (chi 2 = 22.4, P < 0.01). The mean of iMVD/HPF was 24.1 +/- 8.7 in 40 cases of T/NK-cell lymphomas, while the mean of iMVD/HPF was 14.9 +/- 3.8 in 15 cases of B-cell lymphomas. The difference (t = 3.7, P < 0.05) was significant. CONCLUSION: The angiogenic activity of T/NK-cell lymphomas is much more than that of B-cell lymphomas. This study shows nasal/nasopharyngeal T/NK-cell lymphomas are with evident angiogenic activity.

Adult↗