Biomedical subjects

Y Huang

Publications and source records attributed to Y Huang.

At least 541 records · Page 30Linked to original sources

PubMed1999

[The protective effects of prompt escharectomy on myocardial injury following burn in rats].

OBJECTIVE: To investigate the protective effects of prompt escharectomy on myocardial injury following severe burns. METHODS: Rats were inflicted with 30% TBSA III degree scald. They were randomly divided into 3 groups: control group (C, n = 10), non-escharectomy group (NE, n = 50), escharectomy group (E, n = 50). In the E group, burn wounds were excised promptly after the injury. The levels of troponin T (TnT) and tumor necrosis factor (TNF) in plasma and TNF in myocardium were measured at 1, 3, 6, 12 and 24 hours postburn. RESULTS: TnT levels increased markedly at 3 hours post burn, plasma TNF levels increased markedly at 6 hours postburn, and TNF levels in myocardium also increased markedly at 12 hours postburn compared with the C group. Although the levels of TnT and TNF were a little lower in NE group than those in E group at 3 hours post burn, the levels of TnT 6 hours postburn and levels of TNF 12 hours postburn were significantly higher in NE group than those in E group. There were good positive correlations between TNF with TnT levels. CONCLUSIONS: TNF played important roles in the pathogenesis of myocardial injury following burns, its level was correlated with the severity of myocardial injury. TNF levels in E group was much lower that in NE group, suggesting that prompt escharectomy could reduce the production and release of inflammatory cytokines, and lessen the myocardial injury induced by uncontrolled inflammatory response.

Animals↗

PubMed1999

[Soft extravascular model (SEM) with beta-radioactive ray inhibits smooth muscle cell proliferation and intimal hyperplasia in autogenous vein graft].

OBJECTIVE: To investigate the effects of the soft extravascular model (SEM) with 32P on intimal hyperplasia and smooth muscle cell preliferation in autogenous vein grafts. METHODS: We transplanted the femoral veins to the co-lateral femoral arteries in rabbits. The animals were divided into three groups of Aspirin group, 32P group and control group. We observed the expression density of endothelin type A receptor cDNA (ETAcDNA) and intimal relative thickness by using in situ molecular hybridization of ETAcDNA by computerized image analysis technology. RESULTS: SEM with beta-ray obviously inhibited SMC preliferation from 1 W to 12 W postoperation, and notably restrained intimal hyperplasia at early to middle stage of graft. Aspirin could not inhibit SMC proliferation and intimal hyperplasia under the condition of this experiment.

Animals↗

PubMed1999

[Diagnosis of sex chromosome abnormality by fluorescence in-situ hybridization].

OBJECTIVE: To evaluate the diagnostic value of fluorescence in-situ hybridization (FISH) in sex chromosome abnormality. METHOD: alpha-satellits DNA probes of X, Y chromosomes were used to FISH with blood samples from 19 patients with primary anemia or of gonad dysplasia. Five infertile men who were detected abnormal by G-banding analysis during metaphase and interphase. Samples from healthy men and women were used as positive controls and reactions with hybridization fluid without probes as negative controls. RESULTS: The karyotypes, 45, X; 45, X/46, XX/47, XXX; 45, X/46, XY; 47, XXY; 45, X/46, XXX were detected by FISH. Others were not detected by G banding such as 45, X/46, X,r? 46, X,r? but were found to be 45, X/46, X,r(X), 46, X, r(X), by FISH technique, confirming to be X ring chromosome. A female patient whose karyotype was 45, X/46, X, mar. by G banding. But G banding technique could not analyze the property of the marker and FISH revealed the marker was dici(yq), that is dicentric chromosome Y with two long arms of equal length. The real karyotype was 45, X/46, X, dici(yq) mosaicism. It belonged to Y chromosome abnormal and gonadal dysplasia syndrome. CONCLUSION: FISH can help to detect those chromosome abnormalities which can not be confirmed by traditional cytogenetics. It is of value in studying the complex chromosome mutation such as sex chromosome abnormality, unknown little marker, ring chromosome, mosaiciasm and translocation.

Adolescent↗

PubMed1999

[Mechanism of selenium protecting against free radical damages during myocardial ischemia/reperfusion in rats].

OBJECTIVE: To investigate the mechanism of selenium (Se) protecting against free radical damages during myocardial ischemia/reperfusion (I/R) in rats. METHODS: All rats were separated into three groups: control, organic Se and inorganic Se supplemented groups. Myocardial I/R was established by operation in all three groups. Biochemical assays, atomic absorption spectrophotometry, RT-PCR and cDNA sequence scanning were performed to examine the changes in myocardial MDA level, GSH-Px activity and gene expression, GSH-Px cDNA nucleotide sequence, as well as Se and Ca2+ and Mg2+ concentrations in the heart muscle during I/R. RESULTS: The administration of Se for 7 days did not significantly change the content of Se in the plasma and blood cells. In the two Se-supplemented groups, after reperfusion for 30 minutes, myocardial Se concentration and GSH-Px activity were increased significantly, and GSH-Px expression was elevated with a normal cDNA sequence, and at the same time, MDA contents in the two Se-supplemented groups were lower than that in the control group. CONCLUSION: Se supplementation can protect against free radical damages during myocardial I/R by increasing myocardial Se content and improving both the expression and activity of GSH-Px.

Animals↗

PubMed1999

[Mechanism of selenium defending against free radical damages during myocardial ischemia/reperfusion in human].

OBJECTIVE: To investigate the modulate mechanism of selenium (Se) on glutathione peroxidase expression in the myocardium by defending against free radical superoxidizing during myocardial ischemia/reperfusion (I/R) period. METHODS: 46 patients with ASD or VSD were separated into control (23 patients) and Se (23 patients) groups. Patients in the Se group received 400 micrograms Se supplementation each day for 7 days before heart surgery. Biochemical techniques, atomic absorption, RT-PCR, cDNA sequence testing were taken to evaluate and compare the changes in myocadial MDA level, GPX activity, GPX mRNA expression, GPX cDNA nucleotide sequence, and Se, Ca and Mg concentrations during I/R. RESULTS: In Se group, Se supplementation by oral administration neither changed plasma Se content nor blood cells. At 30 minute of myocardial reperfusion, in Se group, Se content in the myocardium did significantly increase but decreased in RBCs, and the elementary rate of GPX activity was lower than that in control. Se group had higher myocardial GPX mRNA expression with a normal nucleotida sequence pre- and post-reperfusion. CONCLUSION: Se supplement, which promotes the myocardial Se content and mainly improves GPX mRNA expression during I/R, can defend against free radical superoxidizing damages to the myocardium.

Adolescent↗

PubMed1999

Comparison of some antineoplastic drugs on inhibiting thrombin catalizing fibrinogen clotting in vitro.

OBJECTIVE: To classify the effect of thrombin, the key enzyme which enables fibrinogen to form fibrin (fibrinogen clotting) on the formation of metastasis by comparing the inhibition of some antineoplastic drugs on fibrinogen clotting in vitro. METHODS: Time intervals of different drugs to reach a maximum OD (340 nm) data in fibrinogen solution added with thrombin were used in this work. RESULTS: It was found that L-4-oxalysine (8-40 micrograms/ml) and arabinosyl cytosine (10-50 micrograms/ml) could inhibit the effect of thrombin by extending the fibrinogen clotting time to 100%-150% (P < 0.001) and 61%-100% (P < 0.001) while the other antimetastatic drugs razoxane, probimane, adriamycin, harringtonine homoharringtonine and alpha-anordrin at the treatment concentrations showed no such activity. The positive rate of drugs to thrombin activity was approximately 25%. CONCLUSION: It suggests that L-4-oxalysine and arabinosyl cytosine may even exhibit antimetastatic effect through thrombin-fibrinogen pathway, and thrombin might operate in tumor metastasis for only limited step but crucial to fibrin formation in tumor nodules.

Amino Acids, Dicarboxylic↗

PubMed1999

[The role of surgery in the management of thyroid lymphoma].

OBJECTIVE: To evaluate the role of surgery in the management of thyroid lymphoma. METHODS: A retrospective analysis was performed of 14 patients with thyroid lymphoma treated at the Cancer Hospital, Peking Union Medical College, Chinese Academy Medical Science from 1964 to March 1998. There were 5 males and 9 females, with a median age of 54 years (range 15-75). There were 4 cases in stage IEA, 9 in stage IIEA, 1 in stage II EB. Fine needle aspiration biopsy was performed in 1 case, excision biopsy in 4, thyroid lobectomy in 8, and total thyroidectomy in 1. Radiotherapy was used alone in 4 patients, chemotherapy alone in 2, radiotherapy combined with chemotherapy in 7, no postoperative treatment in 1. RESULTS: All but 1 patients were histopathologically diagnosed as non-Hodgkin's lymphoma. It was of B cell origin in 11 cases, T cell origin in 2. Seven patients were alive without evidence of recurrent disease at follow-up, ranging from 5 to 112 months. Three patients died of lymphoma, 1 died of treatment complication, 2 died of other diseases, and 1 lost from follow-up. The major surgical resection did not appreciably affect survival. CONCLUSION: Radiotherapy or chemotherapy, alone or in combination, is the treatment of choice for thyroid lymphoma. Surgical resection combined with radiotherapy or chemotherapy may be beneficial to survival in patients with intrathyroid lymphoma. It is otherwise limited to make a tissue diagnosis.

Adolescent↗

PubMed1999

[Changes of interleukin-2 and soluble interleukin-2 receptor serum level and multiple organ dysfunction syndrome in severely traumatic patients].

OBJECTIVE: To evaluate the role in the changes of interleukin-2 (IL-2) and soluble interleukin-2R (sIL-2R) serum level in the mechanism of post-traumatic multiple organ dysfunction syndrome (MODS). METHODS: 59 severe traumatic patients were divided into MODS group (n = 24) and non-MODS group (n = 35) according to the occurrence of MODS after trauma. The changes in IL-2 and sIL-2R serum level were observed by enzyme linked immunoabsorbed assay (ELISA). Sera from 30 healthy individuals were used as normal controls. RESULTS: The serum level of sIL-2R was increased and that of IL-2 decreased in 59 traumatic patients. These changes were more marked in the MODS group than in non-MODS group (p < 0.05). CONCLUSIONS: The changes in IL-2 and sIL-2R serum level after trauma might participate in the mechanism of post-traumatic MODS.

Adolescent↗

PubMed1999

[Allograft-prosthesis combination in limb salvage surgery].

OBJECTIVE: To study allograft-prosthesis combination in limb salvage and the rational of composite prosthesis. METHODS: Of 16 patients with bone tumors age from 19 to 60 years, 6 women 12 men, osteosarcoma was found in 4 patients, chondrosarcoma in 2, malignant giant cell tumor in 3, fibrosarcoma in 3, and other malignant bone tumor in 4. Allograft-prosthesis combination in included allograft proximal femurs with total hip arthroplasty (3 patients), allografts bipolar femoral head replacement (8), allografts with total knee arthroplasty prosthetic replacements (7). All patients received adjuvant therapy for tumor control. RESULTS: The length of follow-up ranged from 18 months to 5 years during which time 1 patients died, 3 survived as tumor-carriers, and 12 were disease free. All patients obtained better functional result in their extremities and had good quality of life. CONCLUSIONS: Both prosthetic replacement and allograft advantages, the use of large bone allografts with metallic prosthesis for the treatment of bone tumors near or involving joints can be applied with good results in selected patients having limb salvage surgery.

Adult↗

PubMed1999

[The PCNA immunohistochemical study of pterygium].

OBJECTIVE: To study the proliferating status of pterygium and the drug's influence on it. METHOD: Fifty four patients with pterygium were randomly assigned into three groups: Before the surgical excision of the pterygium, group 1 (18 cases) had received no drug, group 2 (16 cases) received local dexamethasone treatment, and group 3 (20 cases), local homoharringtonine and dexamethasone treatment. The immunohistochemical study on proliferating cell nuclear antigen (PCNA) was performed on the surgical specimens of the pterygium. RESULT: The PCNA positive rate was (11.53 +/- 3.62)% in the untreated group, (10.28 +/- 4.18)% in the dexamethasone group (P > 0.05), and (5.59 +/- 3.82)% in the homoharringtonine and dexamethasone group (P < 0.01). The PCNA positive rate was higher in the younger patients (< 60 years) with progressive type of the disease than that in the elder patients (>or= 60 years) with quiet type. CONCLUSIONS: There are cell proliferation and PCNA expression in pterygium. The homoharringtonine and dexamethasone local injection before the excision of pterygium can effectively decrease the PCNA expression and recurrence rate of pterygium. Local injection of dexamethasone before surgical excision has no influence on the PCNA expression of pterygium.

Adult↗

PubMed1999

[Studies on immunization strategies for hepatitis B in different endemic areas of China].

OBJECTIVE: To compare the cost-benefit of immunization with hepatitis B (HB) vaccine in different endemic areas of HB and to explore the optimal strategy for it. METHODS: Cost-benefit analysis and comprehensive weighted score analysis (CWSA) were used to screen the optimal immunization strategy for low, medium and heavy endemic areas of HB. RESULTS: Significant economic benefit was obtained in Long-An County, Guangxi Zhuang Autonomous Region, Shanghai and Jinan, Shandong Province from HB immunization programs for infants. The greatest benefit cost ratio (BCR) was provided by the low-dose immunization strategy, which was 49.91, 54.53 and 37.68, respectively for heavy, medium and low endemic areas of HB. The maximal net benefit could be obtained by the high-dose immunization strategy with better immune protective efficacy. CWSA showed that the low-dose immunization strategy was the optimal one for HB immunization. CONCLUSION: It is suggested that the low-dose immunization strategy be implemented in undeveloped areas to obtain a greater BCR, and the high-dose one be implemented in more developed areas to obtain more net benefit and lower prevalence of hepatitis B surface antigen carriage.

China↗

PubMed1999

[Inhibitory effects of recombinant human neurotrophin-4/5 protein on neurotoxicity caused by arsenic trioxide].

OBJECTIVE: To study preliminarily the inhibitory effects of recombinant human neurotrophin (hNT)-4/5 protein on neurotoxicity caused by arsenic trioxide (As(2)O(3)). METHODS: Nerve cells of the chicken embryonic forebrain and PC12 cells were co-cultured with recombinant hNT-4/5 protein and As(2)O(3) (0 - 16 micromol/L) for 24 and 48 hours, respectively, to observe the survival of nerve cells and the outgrowth of PC12 cells, with clone expression and recombination techniques. RESULTS: There was significant difference in survival rate of nerve cells between the experimental and control groups (P < 0.01) after co-culture for 48 hours, and survival rate and number of neuron outgrowth increased with the concentration of hNT-4/5 protein. CONCLUSION: Recombinant hNT-4/5 protein could inhibit neurotoxicity caused by As(2)O(3), which provided a basis to find an anti-toxic factor in the environment by genetic engineering.

Animals↗

PubMed1999

[Influence of nitric oxide upon cerebral infarction in 15 cases].

To study the role of the nitric oxide(NO) in patients with cerebral infarction, NO in cerebrospinal fluid was determined in cerebral infarction group(15 cases) and control group(10 cases). Infarct volume was determined by CT between the second and the 7th day after the onset of symptoms. The severity of neurological deficits was assessed with the stroke scale of Ministry of Public Healthy(China). The results showed that NO was higher in cerebral infarction group (3.12 +/- 1.60) than that in control group(1.19 +/- 1.01) (P < 0.01). The concentration of NO was positively correlated with infarction volume(r = 0.57, P < 0.05) and severity of neurological of deficits(r = 0.54, P < 0.05), respectively. The results support the conclusion that NO produced in large amounts in the postischemic tissue contributes to the progression of the brain damage, which was demonstrated in animal models of focal cerebral ischemia.

Adult↗

PubMed1999

[Measurement of cyclosporine A in whole blood by high performance liquid chromatography(HPLC)].

Whole blood was extracted by ether under base using cyclosporine D as internal standard. The extraction was evaporated and reconstituted. The interferences were further removed by hexane. The reconstitution was injected into a C18 reversed-phase column at 70 degrees C, which was eluted with a mobile phase of acetonitrite/methanol/water(60/10/30, v/v) at flow rate 1.6 ml.min-1 and monitored at 210 nm. Three levels of BIO-RAD cyclosporine A(whole blood) calibrator were measured, all the results were within expected range. The detection limit was 25 ng.ml-1. The linearity was at least within 50-1,000 ng.ml-1. Analytical recoveries were 99.6%-108.8%. The within-run cv and between-run CV were 7.2% and 9.3%, respectively.

Chromatography, High Pressure Liquid↗

PubMed1999

[Significance of the changes of plasma endothelin, norepinephrine and atrial natriuretic peptide in treatment of heart failure with beta-blocker].

Thirty patients with chronic heart failure after conventional treatment for two weeks with cardiac diuretic and vasodilator were divided into two groups. There was addition of betaloc into Group A, but Group B kept the original treatment plan for 8 weeks. Group C consisted of 16 normal controls. The results showed that: 1. The level of plasma endothelin(ET), norepinephrine(NE), atrial natriuretic peptide(ANP) in Group A and B were higher than those in Group C. 2. The decreasing degrees of ET, NE, ANP, heart function score and the increasing degrees of CI and LVEF in Group A were more than those in Group B. 3. The change of ET was related to the changes of the others. Therefore, the beta-blocker may be associated with the decrease of the plasma concentration of ET, NE and ANP and improve heart function. It is considered that the degree of change of plasma ET may be the simple and reliable index which evaluate the degree of improving heart function.

Adrenergic beta-Antagonists↗

PubMed1999

[Effect of decompression or transplantation of the facial nerve on serious advanced facial paralysis].

OBJECTIVE: To investigate operative effect on serious advanced facial paralysis. METHOD: 28 cases (28 sides) with serious facial paralysis underwent decompression or transplantation of facial nerve. RESULT: After following up 0.5-2 years postoperatively, the total, most or partial and no recovery were 14 cases (50%), 12 cases (42%) and 2 cases (7.1%) respectively. CONCLUSION: The operation performed as early as possible can be an effective procedure for correcting serious advanced facial paralysis if conservative treatment could be confirmed to be helpless.

Adolescent↗

PubMed1999

[Effects of acoustic stimuli on intracellular free calcium isolated cochlear OHC].

OBJECTIVE: To study the effects of acoustic stimuli upon intracellular free calcium concentration ([Ca2+]i) of cochlear outer hair cells (OHCs) isolated from guinea pigs. METHOD: The specimens were stained with fluorescence, and measured by using ACAS 570. RESULT: Acoustic stimuli caused a remarkable increase of [Ca2+]i and the concentration of [Ca2+]i decreased gradually after reaching its peak value. The reponeses can repeat with another stimuli. CONCLUSION: The acoustic stimuli could alter the physiologic characteristics of single OHC.

Acoustic Stimulation↗

PubMed1999

[The clinic application of multichannel cochlear implant with eleven cases reported].

OBJECTIVE: To review the effects of profound sensorineural deaf patients who were implanted multichannel cochlear. METHOD: Eleven profound deaf patients (6 prelingually deaf and 5 postlingually deaf) were implanted with twenty-two (model Minisystem 22) and twenty-four (model Nucleus 24) channel cochlear. Mapping of cochlear speech processor was done in 1 to 1.5 months after operation. RESULT: All of 11 patients obtained the hearing. The patients with postlingually deaf can dialog and communicate with telephone after a simple language training without lip reading training. These patients achieved the best results, they not only stepped in sound world but also obtained a normal living and work. In the prelingually deaf patients, they got hold of incoordinate progress in speech ability after assess and speech training. CONCLUSION: The multichannel cochlear implant had good effects in profound deaf patients, especial in postlingually deaf patients and younger children.

Adolescent↗