Biomedical subjects

Y Yang

Publications and source records attributed to Y Yang.

At least 649 records · Page 36Linked to original sources

PubMed1999

The change of insulin-like growth factor-1 in diabetic patients with neuropathy.

OBJECTIVE: To evaluate the possible relationship between insulin-like growth factor-1 (IGF-1) and diabetic neuropathy (DNP). METHODS: Sixty-nine patients with Type 2 non-insulin-dependent diabetes (54 with peripheral neuropathy and 15 without neuropathy) were observed. Normal controls were 34 non-diabetic persons. Diabetic peripheral neuropathy diagnosis was carried out taking into account results of NS, ND, NC and AF. After an overnight fast, blood was taken for IGF-1, glucose, hemoglobin Alc, C-peptide, and insulin. Plasma IGF-1 was measured by radioimmunoassay (RIA) method. RESULTS: The neuropathic group had significantly lower levels for IGF-1 (86.43 ng/ml +/- 45.18 ng/ml) compared to normal controls (119.68 ng/ml +/- 89.42 ng/ml) (P < 0.05), and to diabetic patients without neuropathy (113.75 ng/ml +/- 66.58 ng/ml) (P < 0.05). No significant difference was found between diabetic non-neuropathic group and normal control subjects (P < 0.05). In diabetic subjects there was a positive correlation (gamma = 0.27, P < 0.05) between IGF-1 and beat to variation in heart rate. There were negative correlation between IGF-1 and postprandial blood glucose (gamma = -0.3, P < 0.05), and aspartic acid translocase (gamma = -0.27, P < 0.05). CONCLUSION: In diabetic patients with peripheral neuropathy there are abnormalities of IGF-1 that may contribute to the pathogeneses of diabetic neuropathy.

Aged↗

PubMed1999

Relationship between remodeling and function of left ventricle and angiotensin II AT1 receptor expression after myocardial infarction in rats.

OBJECTIVE: To determine the relationship between remodeling and dysfunction of left ventricle (LV) and the expression of the angiotensin II AT1 receptor mRNA after myocardial infarction (MI) in rats. METHODS: Nine MI rats (Group A) and 8 sham-operated rats (Group B) were studied by both Doppler echocardiography and Dot blot using Digoxingenin-labelled cDNA probes. RESULTS: Compared with Group B, Group A showed the increase in LV internal diastolic diameter (0.87 +/- 0.06 mm vs 0.66 +/- 0.03 mm, respectively, P < 0.01) and volume (0.73 +/- 0.09 ml vs 0.51 +/- 0.05 ml, P < 0.01). In addition, thinning of anterior wall, thickening of posterior wall, increasing of peak early filling velocity (peak E), decreasing of late filling velocity (peak A) and increasing of the E/A were demonstrated in MI rats 7 weeks after MI. The levels of the cardiac angiotensin II AT1 receptor mRNA in Group A were higher than those of Group B (2.2-fold). CONCLUSIONS: Seven weeks after MI in rats, character of LV remodeling and dysfunction were developed and the expression of cardiac angiotensin II AT1 receptor mRNA was increased.

Animals↗

PubMed1999

[Different expressions of bFGF gene in three kinds of skeletal muscles].

OBJECTIVE: To explore the distribution characteristics of bFGF gene, bFGF protein and receptor in rat skeletal muscles. METHODS: bFGF gene, and bFGF protein and receptor in rat gastrocnemius muscles were localized by ABC immunohistochemical method, in situ hybridization and a special staining methods. RESULTS: Based on the results from the special staining, the fibers in rat gastrocnemius muscle could be divided into three types: type I, II a and II b. The positive expression of bFGF gene was only found in the cytoplasm of type I and type II a fibers. The immunohistochemical localization showed that bFGF protein and its receptor were found in the connective parts of muscle endomysium in fibers of type I and type II a. CONCLUSION: This is the first study to identify the different expressions of bFGF gene, bFGF protein and its receptor in rat skeletal muscles. The results will help to understand the action and the relationship between bFGF autocrine and the embryo development of skeletal muscle fibers.

Animals↗

PubMed1999

[Dynamic changes in hepatic myofibroblast of rabbits with Schistosoma japonicum].

OBJECTIVE: To observe the dynamic changes in hepatic myofibroblasts during the formation of schistosomal hepatic fibrosis and to investigate the pathogenesis of hepatic fibrosis. METHODS: Each rabbit was infected with 80 +/- 1 S japonicum. Liver biopsies were done at different time point after infection and the samples were embedded with paraffin and stained with HE and picric acid-sirius red. The dynamic changes in the areas of granuloma were observed, and the extent of liver fibrosis and the expression of alpha-SMA positive cells were semiquantitated. At the 16th week after infection, the rabbits with S. japonicum were received IFN-gamma after treatment of praziquantel and contrasted with the saline group. RESULTS: The granuloma appeared at the 6th week after infection and its areas reached the biggest at the 8th week. Then the granuloma shrinked gradually, but the extent of liver fibrosis aggravated progressively. The alpha-SMA positive cells were observed at the 4th week after infection and their number enhanced gradually. The extent of liver and the expression of alpha-SMA positive cells were significantly different between each treated group, and the IFN-gamma treated group showed the best result. CONCLUSION: The myofibroblasts play an essential role in the formation and development of schistosomal hepatic fibrosis.

Actins↗

PubMed1999

[An analysis of autologous peripheral stem cell transplantation for hematological malignancies].

OBJECTIVE: To summarize the data of autologous peripheral stem cell transplantation (APBSCT) for 49 hematological malignancies patients. METHODS: Forty-nine patients, 18 with acute myeloid leukemia, (AML) 10 acute lymphoblastic leukemia(ALL), 14 multiple myeloma(MM), 6 non-Hodgkin's lymphoma(NHL) and 1 myelodysplastic syndrome(MDS RAEB-t) received APBSCT were retrospectively analyzed. RESULTS: Comparing to conventional chemotherapy, APBSCT can prolong the patients' disease-free survival(DFS) and overall survival (OS). The 3 and 5-year OS rates were 74.78% and 83.33% for AML/NHL; 38% and 19% for MM; 40% and 0 for ALL, respectively. The time of hematopoietic reconstitution was influenced by G-CSF administration significantly. The mean time of neutrophil recovering to 0.5 x 10(9)/L after APBSCT was +17.7 days in no G-CSF group, and +11.14 days in G-CSF group. Up to now, of the 49 patients, no APBSCT related death occur, 23 have died and 22 of them died of relapse. The most common transplantation related complications were fever, liver dysfunction and hypopotassemia, all of which can be cured by proper treatment. CONCLUSION: APBSCT can be safely performed in hematological malignancies.

Acute Disease↗

PubMed1999

Length of protection by murine vaccination with living infective third-stage hookworm larvae.

OBJECTIVE: To determine the length of protection by murine immunization with living third-stage hookworm larvae (L3) as measured by reduction in worm burden and host serologic antibody responses. METHODS: Outbred male (Kunming strain) mice were immunized subcutaneously with 500 L3 once every 2 weeks for a total of immunization for 3 times, and then challenged orally with 1000 L3 for 1 to 8 weeks after the final immunization. Host protective immunity was determined both by the reduction in worm burden as measured by the number of L3 recovered from murine lungs 48-hour post-challenge, as well as by measurement of circulating antibodies. Histopathological responses were also examined. Non-immunized mice served as negative controls. RESULTS: The protection by L3 immunization declined over time. One or 2 weeks after the final immunization, worm burdens were reduced 72% and 77.5% after challenge respectively. In contrast, only 37% reduction in worm burden was observed when the L3 challenge was delayed by 4 weeks and protection was almost entirely lost when there was an 8 week delay between the time of final immunization and challenge. The reduced level of protection over time partially correlated with diminishing L3-specific antibody responses. Host inflammation in the lungs of immunized mice also diminished. CONCLUSION: The protection afforded by living L3 immunization is maximal for the first two weeks after immunization, but then declines significantly over the ensuing weeks.

Ancylostoma↗

PubMed1999

Cutaneous and subcutaneous mast cell and eosinophil responses after challenge in mice vaccinated with living infective third-stage hookworm larvae.

OBJECTIVE: To examine the quantitative and qualitative alterations in mast cells and eosinophils distributed in the cutaneous and subcutaneous tissues of hookworm-infected, uninfected and vaccinated mice. METHODS: Outbred male Kunming strain mice, weighing 18-22 g, were vaccinated thrice by subcutaneous inoculation with 500 living third-stage infective larvae (L3) of Ancylostoma caninum (A. caninum) every 2 weeks, and then challenged subcutaneously with 500 L3 one week after the final immunization. Uninfected mice and non-immunized mice but infected with L3 served as controls. The abdominal skin at the site of percutaneous entry was excised from challenged mice at intervals between 6 hours and 7 days after challenge, fixed, and then examined by light microscopy after staining with either toluidine blue or hematoxylin and eosin. RESULTS: The total number of mast cells appearing in cutaneous, and subcutaneous tissues, and underlying abdominal musculature of immunized mice increased significantly compared with non-immunized mice. Mast cells from hookworm-infected mice showed evidence of membrane rupture and degranulation in contrast to the intact appearance of mast cells from uninfected mice. The degree of mast cell degranulation was greater in vaccinated and challenged mice when compared with non-immunized and infected mice. Similarly, eosinophilic infiltration was greatly enhanced after L3 infection. Tissues from vaccinated mice had a greater number of eosinophils than non-immunized mice after infection. CONCLUSIONS: Mast cell alterations appearing earlier than tissue eosinophilic infiltration is major inflammatory response to Ancylostoma caninum (A. caninum) L3 infection in mice. These processes are more obvious in L3-vaccinated mice.

Ancylostoma↗

PubMed1999

[A study of load stress on an implant and a tooth supported fixed bridge for the first mandibular molar].

OBJECTIVE AND METHODS: A study of load stress on an implant and a tooth supported fixed bridge for the first mandibular molar was performed by means of 3-D FEA in order to reveal the displacement and stress distribution. RESULTS: The results show that the maximum displacement of the second premolar is greater than that of the terminal implant, but there is no difference between the mean (mean) under dispersed load statistically, due to the framework function of the bridge. The stress concentration appears around the neck of the abutments, on the contrary, a little stress is found around the apical portion of the second premolar. When the load concentrates on-to the abutments, the displacement and stress value increase obviously. CONCLUSION: The attention should be paid to the load and occlusion of the terminal implant. This kind of bridge design may be used in clinical practice.

Dental Implantation↗

PubMed1999

[p53 mutations and protein overexpression in primary colorectal cancer and its liver metastasis].

OBJECTIVE: To compare p53 status between primary and hepatic metastatic colorectal cancer in 34 patients. METHODS: p53 gene status (exon 5-9) was examined by PCR, denaturing gradient gel electrophoresis (DGGE) and automated sequencing. p53 protein was detected by immunohistochemistry using monoclonal antibody DO-7. RESULTS: p53 mutations were found in exons 5 through 9 in 21 of 34 patients (61.8%). Among them, 5 patients had mutation in liver metastasis but not in their primary tumor while in the other 4 patients the same mutations were found in both primary and metastatic colorectal cancers. In no patients was p53 mutation exclusively found in the primary colorectal tumor. Moreover, additional mutation was detected in the metastatic lesions in two cases. Of the 37 mutations within the exons examined, 73% was missense mutation and 16% was nonsense mutation. There were 4 microinsertions. p53 protein was overexpressed in both primary and metastatic colorectal cancers with p53 gene mutations. The presence of p53 mutations significantly correlated with p53 protein accumulation (r = 0.96, P < 0.001). However, in 4 patients with p53 nonsense mutation, immunohistochemical staining was negative. In three patients who showed no p53 mutation of the primary tumor, p53 protein was consistently over-expressed. CONCLUSION: In colorectal cancer, p53 gene mutation usually appears first in the primary tumor and maintains as such but more prominent when metastasized to the liver. However, p53 gene mutation may occur only after being metastasized. Although p53 gene mutation and p53 protein overexpression correlate with each other, either parameter examined alone may lead to false positive results.

Colorectal Neoplasms↗

PubMed1999

[Discussion and preliminary application on standard for comprehensive efficacy assessment of traditional Chinese medicine in treating malignant tumor].

OBJECTIVE: To establish a comprehensive efficacy assessment standard on premise of patients' survival period and referring to the response of tumor and host to traditional Chinese medicine (TCM) therapy. METHODS: A standard was established by taking change of tumor size, tumor related symptoms, Karnofsky scoring and body weight of patient as criteria for evaluation. The standard was used to evaluate the comprehensive effect on advanced tumor patients, received various therapeutic regimen of TCM treatment in Xiyuan Hospital from March 1997 to August 1998, and compared with that evaluated by objective response rate (RR) of tumor. RESULTS: By the new standard, comprehensive therapeutic effect of 55 advanced tumor patients was: effective in 17 cases (30.91%), stable in 10 (18.18%) and exacerbative in 28 (50.91%), while by RR, it was completely response in 0, partial response in 3 (5.45%), no change in 41 (74.55%) and progressive disease in 11 (20.00%). Results of evaluation made by the two standard was different significantly, P < 0.005. The median survival period of 18 cases of advanced lung carcinoma patients was 11.5 months. Patients survived longer than the median survival period, mostly were tumor-bearing survival, were attributed to no change by RR, but were listed as effective by the new standard. CONCLUSION: The new standard laid more stress on quality of life than the RR, it reflects better response of tumor and host to treatment, and the prognosis of patients, and associated with the survival period, therefore, it could be conducted as the standard for comprehensive efficacy assessment in treating advanced malignant tumor in clinical practice after further improving.

Adult↗

PubMed1999

[Clinical study on treatment of chronic idiopathic thrombocytopenic purpura by Decoction of Nourishing Blood and Eliminating Purpura].

OBJECTIVE: To observe the clinical effect of treatment of chronic idiopathic thrombocytopenic purpura (CITP) by Decoction of Nourishing Blood and Eliminating Purpura (DNBEP), and study the possible mechanism. METHODS: Effect of 55 patients of CITP in treatment group treated by DNBEP and 22 patients in the control group treated by Antaisu were observed and compared. Their immunologic indexes were determined for exploring the mechanism. RESULTS: The markedly effective, improved and total effective rate of the treatment group were 32.7%, 20.0% and 87.3%, while those of the control group were 4.5%, 9.1% and 45.5% respectively, the difference between the two groups was significant (P < 0.001). The effect of the treatment group was better than the control group in platelet count restoring, hemorrhagic symptoms improving and effect initiating, P < 0.01. Immunologic test showed that the humoral and cell immune function as well as platelet function were abnormal in CITP patients. These functions were improved after treatment, and the effectiveness of the treatment group was significantly superior to that of the control group. CONCLUSIONS: DNBEP is reliable in treating CITP clinically. Its mechanism might be better due to its selective suppression of humoral immune function, bi-directional regulation of cell immune function and recovery of platelet function.

Adolescent↗

PubMed1999

[The clinical features of myocardial infarction in patients younger than 35 years and over 45 years of age].

OBJECTIVE: To investigate the clinical features and the characteristics of coronary angiography in young patients with myocardial infarction. METHODS: 27 patients younger than 35 years with myocardial infarction were studied with respect to their history, habit of smoking and drinking and body weight index. Comparison was made between the left ventricular ejection fraction with ultrasound method and X-ray heart/chest ratio in patients with or without thrombolytic therapy. Selective coronary angiography was performed in 23 of the 27 patients. RESULTS: All of the 27 patients were male. 81.5% of them had smoking index more than 100, 55.5% drinking index more than 150, 51.9% family history of hypertension and 72.2% low blood level of HDL cholesterol. Most of the cardiac accidents took place in the night and morning. 17.4% of the patients had angiographically normal coronary arteries and 30.0% mild stenosis (no significant stenosis). 39.1%, 8.7% and 4.4% of the patients had one-vessel, two-vessel and three- vessel disease respectively. The frequency of patients with left ventricular ejection fraction less than 0.5 was 6.0% in patients with thrombolytic therapy and 33.3% without. CONCLUSION: 47.8% of the patients younger than 35 years with myocardial infarction has no or no significant stenosis of the coronary arteries. Heavy smoking is the most important one of relative factors for young patients with myocardial infarction. Other factors include low blood level of HDL cholesterol, drinking index of more than 150 and family history of hypertension in order. Thrombolysis treatment helps to maintain ventricular performance.

Adult↗

PubMed1999

[The detection of T-cell receptor gene rearrangement in myelodysplastic syndromes].

OBJECTIVE: To analyse the T cell receptor (TCR) gene rearrangement in myelodysplastic syndromes (MDS). METHODS: Polymerase chain reaction (PCR) was used to detect the TCRVgammaI-Jgamma gene rearrangement in 36 cases of MDS. RESULTS: 8 cases (22.2%) were found to have TCRVgammaI-Jgamma gene rearrangement. The TCR gene rearrangement positive rate was higher in RAEB, CMML and RAEBT subtypes than that in RA and RAS subtypes (P < 0.05). The average time MDS evolving to acute leukemia was shorter in the MDS patients with TCRVgammaI-Jgamma for gene rearrangement than that in patients without (P < 0.01). CONCLUSION: TCR gamma gene rearrangement can also be found in some MDS patients and the detection of TCRgamma gene rearrangement might be helpful to identify the prognosis and the development of MDS.

Adolescent↗

PubMed1999

[The correlation of free radicals induced by cadmium toxicess with erythrocyte injury and band3 expression].

OBJECTIVE: To study the correlation of hydrogen peroxide induced by cadmium ion with erythrocyte injury and band3 expression. METHODS: It was application immunoscanning electronmicroscopy and cytochemistry and EDX methods. RESULT: Cadmium ion not only induced a lot of hydrogen peroxide but also caused serious distortion of erythrocyte. CONCLUSION: Cadmium ion-induced free radicals lead to oxygen free radical damage of membrane and crytoskelecton of erythrocyte, affecting the stability and deformability and band3 expression in erythrocyte.

Animals↗

PubMed1999

[Energy dispersive X-ray analysis in studying the permeability of blood-brain barrier caused by lead in rats].

OBJECTIVE: To observe the changes in permeability of blood-brain barrier caused by lead in rats. METHODS: Rats were fed with drinking water containing 10 and 30 mg/L of lead for three months. Electron microscopy lanthanum nitrate-tracing and electron probe-energy dispersive X-ray (EDX) analysis were used to observe the distribution of lead in different cells of bilateral sides of capillaries of cerebral cortex and the changes in their permeability. RESULTS: There was significant difference in blood lead levels between the rats with drinking water of 10 mg/L lead and the controls, but only a peak of lead, L(alpha), could appear in plasmalemma of endotheliaocyte endosurface in capillaries, and no any peak in the basement membrane of endotheliocyte of the outer-side, end feet of astrocytes and axons of neurons. Lanthanum nitrate-tracing showed changes in capillary permeability. But, in those with drinking water of 30 mg/L of lead, peak of lead, L(alpha) and M(alpha) could appear in all cells mentioned above. Meanwhile, lanthanum salt granules, which penetrated the cellular gaps of endothelia and seeped in the basement and its peripheral cells, could be found in certain sites of the capillaries with larger diameters. CONCLUSION: It suggests that the plasmalemma of endotheliocyte endosurface was the initial target in brain, where was affected by lead, and the consecutive endotheliocytes of blood vessels served as a blood-brain barrier to lead, although in a very weak action. A little bit accumulation of lead on the plasmalemma of endotheliocyte endosurface could cause damage in the close junction between endotheliocytes to spread to brain substance, same as the lanthanum tracing showed.

Animals↗

PubMed1999

[Application of cerium cytochemical method in observation of renal injury caused by oxygen free radical with cadmium induction].

OBJECTIVE: To study acute renal injury caused by oxygen free radical with cadmium induction. METHODS: Electron microscopy cytochemical and energy dispersive X-ray (EDX) analysis techniques were used. RESULTS: Cadmium ions could enter the epithelial cells of renal proximal convoluted tubules. Excessive production of oxygen free radical was found in the kidney tissues, which located mainly in the endothelial cells of blood vessels, mitochondria of epithelial cells of renal proximal convoluted tubules, microvilli and basement membrane. Swelling of epithelial cells and mitochondria and drop of epithelial cells could occur in renal proximal convoluted tubules. CONCLUSION: It suggests that cadmium ions can induce the formation of large amount of oxygen free radical and cause renal injury.

Acute Kidney Injury↗

PubMed1999

[Study of BAEP, TCD and neck rotation test in vertebrobasilar-artery insufficiency patients].

Forty patients with vertebrobasilar-artery insufficiency(VBI) were checked by BAEP and BAEP together with neck-rotation test. Their positive rates were compared with those of TCD. The results showed that: 1. the positive rate of BAEP was 50%, lower than that of TCD; 2. after neck rotation test, the positive rate of BAEP increased from 50% to 86.3%. The results suggest that BAEP together with neck rotation test can obviously increase the positive rate of BAEP. The method is simple and effective in clinical application.

Adult↗

PubMed1999

[Effect of cerous nitrate on the activity of ATPase in tissues].

The effect of cerous nitrate on the activity of some ion-dependent ATPase such as Ca(2+)-ATPase, K+, Na(+)-ATPase and Mg(2+)-ATPase was studied in vivo. The results showed that Ca(2+)-ATPase, K+, Na(+)-ATPase and Mg(2+)-ATPase activity was increased in rat liver, kidney and heart after recurrent intraperitoneal administration of low dose of cerous nitrate(1 mg/kg), but no changes happened for these enzymes activity after high cerous nitrate administration(50 mg/kg). The mechanism of the phenomena was discussed.

Animals↗