Biomedical subjects

Y Yao

Publications and source records attributed to Y Yao.

At least 55 records · Page 3Linked to original sources

PubMed2001

Possible roles of cardiac chymase after myocardial infarction in hamster hearts.

The significance of cardiac chymase after myocardial infarction (MI) was evaluated using a hamster model of MI. At 1, 3, 7, 14, 28 and 56 days after MI, tissues were removed for measurements of angiotensin-converting enzyme (ACE) and chymase activities. The mean infarct size 3 days after left coronary artery ligation was 47.3 +/- 5.9% of the left ventricle circumference. The ratio of left ventricle weight to body weight was significantly increased from 3 days after MI. The level of plasma renin activity in the MI hamsters was significantly increased at the early phase of MI (1-3 days), while no significant changes in plasma ACE activity were observed. The ACE activity in the infarcted left ventricle was significantly increased starting from 3 days after MI and this increase was sustained up to 28 days. The chymase activity in the infarcted left ventricle was significantly increased starting from 1 day after MI and this increase was sustained up to 56 days. The number of chymase-positive mast cells in the infarcted left ventricle was significantly higher than in the sham group 3 and 7 days after operation. Treatment with an angiotensin (Ang) II type 1 receptor antagonist (candesartan cilexetil, 10 mg/kg per day) starting 3 days before the induction of MI significantly reduced the mortality rate during 14 days of observation following MI, whereas treatment with an ACE inhibitor (lisinopril, 20 mg/kg per day) did not. A significant improvement in hemodynamics (maximal negative and positive rates of pressure development, left ventricular systolic pressure and end-diastolic pressure, mean arterial blood pressure) was observed by the treatment with candesartan cilexetil, but not with lisinopril, 3 and 14 days after MI. These results suggested that Ang II produced by chymase may participate in the pathophysiologic state after MI in hamsters.

Angiotensin Receptor Antagonists↗

PubMed2001

Construction and performance characteristics of new fentanyl-selective plastic membrane electrode.

The construction and performance characteristics of an ion-selective electrode for fentanyl-drug cation, based on an ion-pair complex with tetrakis[3,5-bis-(trifluoromethyl)phenyl]borate anion in a PVC matrix were studied. A linear response for 1 x 10(-5) mol dm-3 to 1 x 10(-2) mol dm-3 drug with a slope of 57.9 +/- 0.5 mV/decade was established. The optimum pH range was 2 to 6. The lower detection limit was 6.29 x 10(-6) mol dm-3 fentanyl citrate (2.1165 micrograms cm-3 fentanyl). There were negligible interferences from a number of inorganic cations, structural analogues, and some common drug additives in injections. The electrode proposed has been successfully applied to determine fentanyl citrate in injections. The results correlated well with those obtained by the United States Pharmacopoeia standard procedure.

Chemistry, Clinical↗

PubMed2001

Percutaneous sclerotherapy for congenital venous malformations in the extremities.

Between January 1991 and January 1998, a total of 15 patients underwent direct injection sclerotherapy for painful peripheral venous malformations. Duplex ultrasonography or venography was used in all cases for the detection and localization of tortuous venous structures. Direct injection with absolute ethyl alcohol was performed in 12 patients, and Sotradecol or sodium morrhuate was used in 5 patients. Provocative lidocaine testing was used in 2 patients in whom major nerves were in proximity to the malformations. All patients underwent follow-up in the clinic with duplex examination after each sclerotherapy. Clinical symptoms of all patients improved during average follow-up of 2.5 years (range: 3 months to 6 years.) Duplex examination was useful in detecting the venous component including the size and course of veins, which were often less well seen on magnetic resonance imaging. Duplex study was helpful in follow-up after sclerotherapy in all patients. Direct injection sclerotherapy is an acceptable treatment modality for venous malformations. Complications are manageable, and regular follow-up with Duplex is helpful.

Adolescent↗

PubMed2001

[Endoscopic thoracic sympathectomy for palmar, axillary and plantar hyperhidrosis: intermediate-term results].

From June 1996 to June 2000, 477 endoscopic thoracic sympathectomies (ETS) were performed in 242 patients with palmar hyperhidrosis. Among these, 190 patients were studied who received bilateral sympathectomy (T 2-T 3 ganglionectomy) and were followed for over six months. There were 114 females and 76 males with a mean age of 26 years. Palmar hyperhidrosis was found in all patients and axillary hyperhidrosis in 138 (73%) and plantar hyperhidrosis in 186 (98%) preoperatively. The degrees of palmar, axillary and plantar perspiration were checked immediately (1-2 weeks, 190 patients), as well as in the early (1 year, 190 patients) and late (2-4 years, 65 patients) postoperative periods. In all patients, the hands became dry or normal condition immediately after the operation, and this continued to late period. Disappearance or decrease of axillary sweating was found in 128 patients (93%) in the immediate period and 107 patients (78%) in the early period. Disappearance or decrease of plantar sweating was found in 134 patients (72%) in the immediate period and 115 patients (62%) in the early period. Among 65 patients examined in the late period, axillary hyperhidrosis was found in 24 (37%), and plantar hyperhidrosis was found in 52 (80%). Compensatory sweating was found in 80 patients (42%) in the immediate period and 137 patients (72%) in the early period. In the late period, compensatory sweating developed in 56 patients (86%). In the immediate period, 175 patients (92%) were satisfied with the results of the operation, but this decreased to 83% and 72% at early and late period. However ETS was remarkably effective for palmar or axillary hyperhidrosis and relatively effective for plantar hyperhidrosis, but development of compensatory sweating did occur in some cases.

Adolescent↗

PubMed2001

[Influence of electroporation on the biological activities of primary rat hepatocytes].

OBJECTIVE: To investigate the influence of electroporation on the biological activities of primary rat hepatocyte and to optimize the electroporation conditions introducing foreign genes into hepatocytes. METHODS: A single-pulse procedure was performed at low voltage (220-400 V) but high capacitance (500-950 microF). Its influence on hepatocyte activities was detected by Trypan blue exclusion (TBE) and MTT analysis. Besides, ALB, ALT and LDH in the supernatants of hepatocytes were tested by biochemical assay. RESULTS: Little hepatocyte damage and high survival rate (>90%) was found from 36 hours till 9th day of culture. At 36th hour after electroporation, ALB, ALT and LDH in the supernatants of Group B (220V, 950 microF) and C (400 V, 950 microF) were higher than those of control group. Whereas TBE and MTT analysis failed to indicate the significant difference of cell viability between electroporation groups and control group. CONCLUSIONS: This electroporation procedure is one of the optimal choices to introduce foreign genes into primary rat hepatocytes.

Animals↗

PubMed2001

[Construction of a dicistronic expression plasmid vector containing double-valent hepatitis B surface gene].

OBJECTIVE: In order to enhance vaccine response, we constructed a dicistronic expression plasmid containing double HBsAg immunogenes. METHODS: At first, pcDNA3.1 plasmid vector was digested with NheI and EcoRI to get the coding sequence of the small (S) surface protein of HBV, then cloned into pCI-neo vector and named it pCI-S. By PCR amplification, the product of IRES-S was digested with SalI & BamHI, and cloned into pBluescript IIK+S to generate pBKS-IRES-S vector, then subcloned to the pCI-S plasmid to generate pCI-S-IRES-S, which is a dicistronic plasmid of double value HBsAg genes. RESULTS: Two plasmids we constructed were digested with related restriction nucleic enzymes. Sequence analysis of HBsAg and IRES-S gene did not reveal any mutation. CONCLUSIONS: The construction of dicistronic plasmid of divalue HBsAg immunogenes has been well cloned, which is convenient for further research on cell expression and gene immunization in animals.

Antigens, Viral↗

PubMed2001

Fentanyl-selective polymeric membrane electrode.

A poly (vinyl chloride) membrane electrode with dibutyl phthalate as plasticizer based on a fentanyl-tetrakis(4-chlorophenyl)borate ion-pair complex for the determination of fentanyl citrate in injections is described. A linear response over the range 1 x 10(-5) mol.dm-3 to 1 x 10(-2) mol.dm-3 drug with a slope of 59.3 +/- 0.6 mV/decade was established. The optimum pH range was 1 to 6. The lower detection limit was 8 x 10(-6) mol.dm-3 fentanyl citrate (2.7 micrograms cm-3 fentanyl). There were negligible interferences from a number of inorganic cations, structural analogues, and some common drug additives used in injections. The electrode proposed has been successfully applied to determine fentanyl citrate in injections. The results correlated well with those obtained by the United States Pharmacopoeia standard procedure.

Chromatography, High Pressure Liquid↗

PubMed2001

Macrophage infiltration-associated thymidine phosphorylase expression correlates with increased microvessel density and poor prognosis in astrocytic tumors.

PURPOSE AND EXPERIMENTAL DESIGN: To clarify the significance of thymidine phosphorylase (TP)/platelet-derived endothelial cell growth factor/gliostatin in human glioma, we examined TP expression immunohistochemically in a series of 50 astrocytic tumors and correlated its expression with tumor angiogenesis and apoptosis, as well as prognosis. RESULTS: The majority of TP-positive cells were of macrophage origin, which was confirmed by immunostaining TP and CD68 on mirror sections. TP expression was significantly associated with glioma malignancy grading, intratumoral microvessel density, and VEGF expression but showed no relationship with apoptotic index or P53 expression. Regardless of glioma grading, patients with TP-positive tumors had a significantly shorter mean survival time than those with TP-negative tumors. CONCLUSIONS: These findings suggest that TP might play a crucial role in angiogenesis during glioma development, and immunodetection of TP is useful for clinical prediction. Further studies are necessary to better elucidate the role of TP in glioma, which may provide insights into adequate TP-targeted therapy.

Antigens, CD↗

PubMed2001

[Changes in serum neopterin levels in patients after trauma].

OBJECTIVE: To evaluate the clinical significance of changes in serum neopterin levels in patients after trauma. METHODS: 41 patients with mechanical injury were divided into three groups according to the injury severity score (ISS). In all patients, blood collection was started within 24 h after injury, and blood samples were obtained at 3, 7, 14, and 21 d post-trauma. The relationship was determined between serum neopterin levels and ISS, multiple organ dysfunction syndrome (MODS) and prognosis in patients. RESULTS: Patients with ISS > or = 25 showed a high neopterin level compared with those with ISS < 16 (P < 0.05 or P < 0.01), and a correlation between mean neopterin levels and ISS was observed in severely injured patients (r = 0.518, P < 0.05). High neopterin levels were measured in patients who developed MODS, showing a persistent marked elevation from day 3 post-trauma onward. The difference between MODS and non-MODS patients was significant on days 3, 7, and 14 after acute insults (P < 0.05 or P < 0.01). In addition, serum neopterin levels of patients with fatal outcome were much higher than those of surviving patients, and it exceeded 50.0 nmol/L in most cases prior to termination (8/12 cases, 66.7%). CONCLUSIONS: Mechanical injury can cause a constant increase in neopterin level, implying an intact reaction by T lymphocytes and macrophage axis. The measurement of serum neopterin might serve as a tool for the evaluation of injury severity, early detection of MODS as well as prediction of outcome in patients after trauma.

Adult↗

PubMed2001

[Study on the replication of hepatitis B virus compared with that of duck hepatitis B virus in primary duck hepatocytes].

OBJECTIVE: By studying the replication of Hepatitis B virus (HBV) compared with that of Duck Hepatitis B virus (DHBV) in primary duck hepatocytes (PDH), we want to explore the host-specific regulating roles on the replication of HBV in hepatocytes from heterologous species. METHODS: PDH were transfected with complete HBV genome by electroporation (transfected group, 1.19 x 10(12) copies of linear HBV DNA/1 x 10(7) PDH) or infected with DHBV (infected group, 4 x 10(8) virions/1 x 10(7) PDH). 1, 3 and 5 days after transfection or infection, HBsAg, HBeAg and DHBsAg in the supernatant and lysate of PDH were measured with IMX System or ELISA. Meanwhile, replicative intermediates of HBV DNA and DHBV DNA were analyzed by Southern blotting and dot blotting. PDH electroporated only was used as control group. RESULTS: HBsAg in the lysates of transfected group were 15.24 (1 day), 14.55 (3 days) and 5.13 (5 days; P/N values, positive > or = 2.1), HBeAg all was negative (< 2.1), and both were negative in the supernatants of transfected group. DHBsAg in the supernatants of infected group were 14.6 (1 day), 31.53 (3 days) and 34.73(5 days; S/N values, positive > or = 2.1). Dot blotting revealed that both the total amount of HBV DNA in the transfected group and DHBV DNA in the infected group were strongly positive, whereas that of the control group was negative. Southern blot analysis of intracellular total DNA indicated that there are relaxed circular (RC), covalently closed circular (ccc) and single-stranded (SS) HBV DNA replicative intermediates in the transfected group, there was no integrated HBV DNA in the cellular genome, as the same as that of DHBV DNA in the infected group. Control groups were negative at all. CONCLUSION: Our results demonstrate that expression of HBV genes and production can occur in hepatocytes from nonmammalian species and strongly support the idea that HBV replication has no critical species-specificity, and yet hepatic-specific regulating factors could be essential for viral replication.

Animals↗

PubMed2001

[The dynamic change in the expression of interleukin 18 mRNA in the tissue of scalded rats after delayed resuscitation].

OBJECTIVE: To explore the dynamic change in the expression of interleukin 18 (IL-18) mRNA in the tissue of scalded rats after delayed resuscitation. METHODS: Wistar rats inflicted by 30% TBSA III degree scalding were employed as the model. Fifty-four rats were randomly divided into normal control (C), scalding and delayed resuscitation group (SD) and preventive group of selective decontamination of digestive tract (SDD) group. The RT-PCR was applied to determine the tissue contents of IL-18 mRNA in intestine, lungs, liver and kidneys at 2, 8, 16 and 24 PBHs. RESULTS: Plasma level of LPS increased significantly and reached summit level at 8 and 24 PBHs after delayed resuscitation after scalding (P < 0.01), but decreased obviously (P < 0.05) after the preventive application of SDD. Furthermore, the expression of tissue IL-18 mRNA in lungs, liver and kidneys since 2 PBHs increased evidently when compared to that before scalding and reached peak value at 8 PBH (P < 0.01) and lasted up to 24 PBHs. The expression of IL-18 mRNA could be inhibited to varying degrees by preventive application of SDD (P < 0.05-0.01). It was indicated by correlative analysis that plasma level of LPS was positively correlated to the expression of tissue IL-18 mRNA in intestine, lungs and liver (r = 0.298, 0.290 and 0.365 respectively with P < 0.05-0.01). CONCLUSION: The expression of tissue IL-18 mRNA in intestine, lungs, liver and kidneys increased significantly during early postburn stage and progressively enhanced thereafter. And the expression of tissue IL-18 mRNA in a variety of body tissue was significantly affected by post-traumatic endotoxemia.

Animals↗

PubMed2001

[Serum leptin level in hemodialysis patients and its relation to their nutritional status].

OBJECTIVE: To investigate the leptin levels of hemodialysis (HD) patients and the relation to their nutritional status. METHODS: Thirty maintenance hemodialysis patients and thirty healthy control subjects were recruited for the study. Blood was drawn after an overnight fast. Serum leptin was measured using a human leptin RIA kit. There were also blood tests to measure BUN, creatinine, serum albumin, transferrin, prealbumin, insulin, cholesterol etc. RESULTS: Mean serum leptin concentration was significantly higher in the HD group than that in the control (P < 0.01). HD group had significantly higher concentrations of BUN, creatinine, serum albumin, transferrin and prealbumin (P < 0.01). Leptin levels in HD patients correlated positively with body mass index (BMI), total systemic flow (TSF), and concentration of insulin (r = 0.53, 0.66, 0.57, respectively, P < 0.01). No significant correlations were observed in HD patients between leptin and BUN or creatinine, or between leptin and nutritional indices. CONCLUSION: Our data suggests that leptin is markedly increased in HD patients. Serum leptin correlates strongly with BMI, TSF and insulin level. No significant correlations were observed in HD patients between leptin and other indices.

Adult↗

PubMed2001

[Determination of nitidine in different parts of Zanthoxylum nitidum].

OBJECTIVE: To determine the nitidine in different parts of Zanthoxylum nitidum (Roxb.) DC. METHODS: HPLC method was used. The column was HYPERSIL BDS C18. The mobile phase was 0.02 mol/L monobasic potassium phosphate: acetonitrile (66:34). The detective wavelength was 328 nm. RESULTS: The average recoveries and RSD for nitidine was 100.24%, 1.83% respectively. The root contained more nitidine than other parts. CONCLUSION: The method can be used for the quality control of Zanthoxylum nitidum (Roxb.) DC. The roots were the best part for medicine.

Benzophenanthridines↗

PubMed2001

[Treatment of the ocular burn with hormone].

OBJECTIVE: To explore new ways of the management of ocular burn with the use of hormones (human growth hormone and corticosteroid). METHODS: Twenty-one patients (30 eyes) with ocular burn were enrolled in the study. Nine cases (12 eyes) were treated with routine methods, while in 12 cases (18 eyes) corticosteroid and recombinant human growth hormone (rhGH) were used. The corticosteroid was applied immediately postburn both systemically and topically and continued for 2-4 weeks. But the rhGH was applied after 1 week postburn and continued for 2 weeks. The results in the above two groups were compared. RESULTS: Compared with those in control group, all the 18 eyes in the 12 patients with ocular burn were saved and cured with the treatments of hormones. There was significantly less incidence of corneal ulceration and perforation and better visual recovery in those treated with the hormones. CONCLUSION: Combined application of corticosteroid and rhGH might be beneficial to the management of patients with ocular burn.

Adrenal Cortex Hormones↗

PubMed2001

[A comparative study on wound healing treated by different doses of bovine basic fibroblast growth factor (bFGF)].

OBJECTIVE: To explore the optimal dosage and method of bFGF application on surgical wound for accelerating its healing. METHODS: Laceration wounds on the extremities of 73 patients were served as the target. The wounds were applied with three different doses of bFGF (75 Au/cm(2), 150 Au/cm(2), 300 Au/cm(2)) and with three application methods, i.e. once a day, three times a day and once a day with moistening. Normal saline with 0.5% metronidazol was employed as control agents. The wound healing time in every groups was recorded in days and compared with each other. RESULTS: When compared to each other, the wound healing time (day) was much shorter (P < 0.05) with bFGF application in dose of 75 similar 300 Au/cm(2). There were also obvious differences in wound healing time among groups treated with the same dose but with different methods (P < 0.01). In addition, three times a day and once a day with moistening of bFGF application could further shorten the wound healing time. CONCLUSION: Compared to the dosage of the agent, the frequency and method of bFGF application seemed more important for its optimal effects. In view of the convenience, feasibility and economy, once a day with moistening was recommended for clinical application.

Adolescent↗

PubMed2001

[The predictive value of serum neopterin for multiple organ dysfunction syndrome in extensively burned patients].

OBJECTIVE: To evaluate the predictive value of serum neopterin for multiple organ dysfunction syndrome (MODS) in extensively burned patients. METHODS: Twenty-nine burn patients with TBSA of more than 70% were included in this study, and these patients were divided into two groups according to the occurrence of MODS. Blood samples were obtained on 1, 3, 7, 14, 21 and 28 postburn days (PBDs). And serum neopterin levels were determined by radioimmunossay. To evaluate the predictive power of neopterin, sensitivity, specificity, predictive value of a positive/negative test were calculated for the diagnosis of MODS. RESULTS: Serum neopterin levels in MODS group were significantly higher than those in non-MODS group on 3, 7, 14 and 21 PBDs (P < 0.05 similar 0.01). And a positive correlation was found between neopterin levels and MODS scores in patients who developed MODS on 3, 7 and 21 PBDs (r = 0.470 similar 0.811). In a period of up to 28 PBDs, neopterin levels exceeding 35.0 nmol/L were associated with MODS by a clinical sensitivity of 81.1%, a specificity of 89.9%, a positive predictive value of 81.1%, and a negative predictive value of 89.9%. CONCLUSION: These data indicated that the presence of constant high neopterin serum levels appear to be associated with the development of postburn MODS. Serum levels of neopterin might be a useful marker for the early identification of extensive burned patients at risk for MODS.

Adolescent↗

PubMed2001

[Preliminary investigation of the relationship between liver lesion and relevant factors in young children with rotavirus diarrhea].

OBJECTIVE: To investigate the possibility of liver lesion and its relationship with the relative factors in young children with rotavirus(RV) diarrhea. METHODS: The values of ALT and AST in sera of young children with RV diarrhea were measured to be compared with those of common diarrhea and were analyzed with the multifactors about diarrhea. The genomes of RV from blood serum were tested with reverse-nest polymerase chain reaction. RESULTS: Of the 41 young children with RV diarrhea, 15(36.6%) and 32 cases (75.6%) were abnormally higher in the level of ALT and AST respectively and both the ratio and degree of increase were significant in comparison with that in control group. There was no significant relation between the changes of the values of ALT and AST and the clinical manifestation of diarrhea. 4 out of 41 cases were found to be positive of viremia. CONCLUSION: RV infection might spread from intestine to blood and to other organs resulting in viremia, and the liver may be one of the organs involved.

Child, Preschool↗

PubMed2001

[Studies on insulin-like growth factor I receptor in fetal rats with intrauterine growth retardation].

OBJECTIVE: This study was conducted to detect the localization of the insulin-like growth factor I receptor (IGF-I R) in the cells and tissues in the rats with intrauterine growth retardation (IUGR) and normal growth rats. METHODS: 21 pregnant rats were randomly divided into the experimental group (IUGR) (n = 12) and the control group (n = 9). Animal models for IUGR were established by clamping the uterine vasculature of pregnant rats for 20 minutes on day 14 of gestation. The control group rats were subjected to Sham-operation. On day 22 of gestation, fetal rats were delivered by cesarean section. Immunohistochemical assay was performed to detect the IGF-I R expression on liver and lung using specific polyclonal antibodies to rat IGF-I R. RESULTS: In the experimental group, the IUGR rats' body weight, height, and the weight of their liver, lung and the placenta were significantly lower than those in the control group. In the IUGR rats' liver, the area ratio of IGF-I R was increased and the average gray level was decreased, compared with those in the control group. In the IUGR rats' lung, the area ratio of IGF-I R was increased, compared with that in the control group, but no difference of average gray level was observed between the two groups. CONCLUSION: The increased expression of IGF-I R in rats with IUGR, may be due to the decrease of IGF-I and the compensative mechanism of the body.

Animals↗