Biomedical subjects

G Liu

Publications and source records attributed to G Liu.

At least 253 records · Page 14Linked to original sources

PubMed2000

[Effect of emodin on fibroblasts in lupus nephritis].

OBJECTIVE: To observe the effects of emodin on human fibroblasts in culture of kidney in patients with lupus nephritis (LN). METHODS: Fibroblasts were isolated from culture of kidney of LN patients, and the effect of emodin on 3H-TdR incorporated rate of fibroblasts was observed. The apoptosis and c-myc gene expression were detected in the same time by flow cytometry. RESULTS: Emodin could inhibit the proliferation of fibroblasts, and promote the programmed cell death through upregulate c-myc gene expression in human renal fibroblasts. CONCLUSION: Emodin can inhibit proliferation and promote apoptosis of fibroblasts, which may be important in ameliorate interstitial fibrosis, thus improving prognosis of LN.

Apoptosis↗

PubMed2000

[Quantitative evaluation of dyspnea and the effects of M-receptor antagonist on dyspnea in patients with chronic obstructive pulmonary disease].

OBJECTIVE: To study the method of quantitative evaluation of dyspnea and to investigate the effects of M-receptor antagonist inhalation on dyspnea in patients with chronic obstructive pulmonary disease (COPD) during exercise. METHODS: Cycle exercise test was used in 27 patients with COPD and the effects of ipratropium bromide, a M-receptor antagonist, by inhalation on dyspnea and exercise capacity in the patients were observed. RESULTS: (1) Dyspnea index as Borg scale was closely correlated with oxygen uptake (V(O2)) during exercise in all the patients. Three variables for quantitative evaluation of dyspnea could be derived from the linear regression line. They were Borg scale slope (BSS), threshold load of dyspnea (TLD), and breakpoint load of dyspnea(BLD). (2) BSS was negatively correlated with forced expiratory volume in one second to forced vital capacity ratio (r = -0.519, P < 0.01) and diffusing capacity of the lungs for carbon monoxide (r = -0.497, P < 0.01) but positively correlated with residual volume/total lung capacity (r = 0.396, P < 0.05). (3) Inhalation of ipratropium bromide could significantly improve BSS [from (12.09 +/- 3.41) BS x L(-1) x min(-1) to (8.57 +/- 2.79) BS x L(-1) x min(-1), P < 0.01] and BLD [from (0.77 +/- 0.19) L/min to (0.81 +/- 0.14) L/min, P < 0.05] during exercise. CONCLUSIONS: (1) BSS, TLD and BLD could be used as reliable and convenient variables in quantitative evaluation of dyspnea in patients with COPD. BSS and BLD could to some extent reflect the severity of the disease. (2) M-receptor antagonists could alleviate dyspnea and increase exercise capacity in patients with COPD.

Adult↗

PubMed2000

[Clinical types of pheochromocytom].

OBJECTIVE: To improve the diagnosis and treatment of pheochromocytoma. METHODS: 90 patients with pheochromocytomas were treated from June 1987 to August 1998. These patients showed extra-adrenal (14 patients), non-symptomatic (5), recurrent (8), malignant (15), bilateral or multiple (4), and familial or MEN-IIA (5). RESULTS: One patient with malignant extra-adrenal pheochromocytoma showed extensive metastasis. All the patients except this patient were confirmed pathologically. 36 patients were followed up for 5 months - 10 years. Eight patients had recurrence and 3 showed malignancy. CONCLUSIONS: Open surgery is an effective method for pheochromocytoma. Preoperative preparation must be sufficient to make the operation safe. Recurrent pheochromocytomas are not malignant in nature, but they have considerable malignant tendency and should undergo intensive surveillance and regular examinations. Familial pheochromocytomas are bilateral or multiple. They could develop into secondary medullar thyroid carcinoma in the meantime.

Adolescent↗

PubMed2000

[Staple in pericardial devascularization of upper GI bleeding due to portal hypertension: application and therapeutic effect].

OBJECTIVE: To investigate the therapeutic effect of staple in pericardial devascularization on upper GI bleeding due to portal hypertension. METHODS: From July, 1997 to July, 2000, 30 portal hypertensive patients were treated by using pericardial devascularization plus partial resection of lower part of the esophagus with staple (CDH25). The eliminating rate of varicose veins of the lower part of the esophagus and the stenosis rate of anastomosis were evaluated. The therapeutic effect of pericardial devascularization without lower part esophageal resection in 28 patient with upper GI bleeding due to portal hypertension was taken as control. RESULTS: All the patients were followed up for 23 months. There was no death due to the operation. All patients in the study group had no upper GI rebleeding during the 23-month follow-up. The rebleeding rate in the control group was 18% (5/28) (P < 0.05 vs. Study group). The varicose veins eliminating rate was 100% in the study group and 53.6% (15/28) in the control group (P < 0.01); the stenosis rate of anastomosis was 6.7% (2/30) in the study group. CONCLUSION: The therapeutic effect of pericardial devascularization could be improved by the use of staple with shorter operative time.

Adult↗

PubMed2000

[The study of beta-fibrinogen gene - 455 G/A, - 148 C/T, 448 G/A polymorphisms and their association with plasma fibrinogen levels].

OBJECTIVE: To analyze the frequency of beta-fibrinogen (beta-Fg) gene - 455 G/A, - 148 C/T, 448 G/A polymorphisms and their association with plasma fibrinogen levels in Han nationality in Guangdong Chinese. METHODS: The beta-Fg gene - 455 G/A, - 148 C/T, 448 G/A polymorphisms of 156 individuals were analyzed by restriction fragment length polymorphism (RFLP). Plasma fibrinogen levels were determined by turbidimetry. RESULTS: The frequencies of A(- 455), T(- 148) and A(448) allele were 0.276, 0.285 and 0.272, respectively. There were strong linkages of G(- 455), C(- 148) and G(448), and of A(- 455), T(- 148) and A(448), the correspondence was more than 97%. The plasma fibrinogen levels in the presence and absence of A(- 455) allele were (3.13 +/- 0.74) g/L and (2.89 +/- 0.57) g/L (P < 0.05); of T(- 148) allele were (3.12 +/- 0.73) g/L and (2.89 +/- 0.58) g/L (P < 0.05); and of A(448) were (3.13 +/- 0.74) g/L and (2.89 +/- 0.57) g/L (P < 0.05), respectively. The plasma fibrinogen levels of the three polymorphisms with the mutant gene are significantly higher than that in the wild type. CONCLUSION: The three polymorphisms loci are strong linkage disequilibrium. It suggests that beta-Fg gene - 455 G/A, - 148 C/T, 448 G/A polymorphisms are associated with plasma fibrinogen levels.

Adult↗

PubMed2000

[mRNA and protein expression of skeletal DHPR(alpha1) and RyRs in diaphragm muscle of rabbits].

To detect mRNA and protein expression of skeletal dihydropridine receptor isoform alpha1 subunit and ryanodine receptor 1 and 3 in diaphragm muscle of rabbits, the coupling mode and characteristics of Ca(2+) release were explored. Reverse transcription PCR, in situ hybridization and immunohistochemical methods were employed. A higher level of mRNA and protein expression of DHPR(alpha1) and RyR(1), and a lower level of mRNA expression of RyR(3) were found. It is suggested that the calcium release unit may consist of skeletal DHPR isoform, RyR(1) and RyR(3), and there may be two kinds of Ca(2+) release mode via conformational changes in linked proteins and Ca(2+)-induced Ca(2+) release (CICR) in diaphragm muscle of rabbits.

Animals↗

PubMed2000

[The correlation between anticardiolipin antibodies and disease activity in patients with systemic lupus erythematosus].

This study was conducted to determine the prevalence and clinical association of anticardiolipin antibodies (ACA) in serum of patients with systemic lupus erythematosus (SLE). ACA (IgG, IgA, IgM) was measured by enzyme-linked immunosorbent assay (ELISA) in the serum sample of 87 patients of SLE. The prevalence rates of ACAIgG, ACAIgA and ACAIgM were 62.1%, 52.9% and 35.6% respectively. The titers of ACAIgG and ACAIgM were positively correlated with the disease activity (r = 0.2763, P = 0.044; r = 0.3294, P = 0.018); ACAIgG, ACAIgA and ACAIgM were negatively correlated with complement C3 (r = -0.4737, P = 0.000; r = -0.2990, P = 0.017; r = -0.2758, P = 0.029); and ACAIgG was negatively correlated with complement C4 (r = -0.4079, P = 0.005). The titers of ACAIgA in patients with thrombosis was higher than that in patients without thrombosis. The patients with central nervous system involvement (CNS-SLE) had significantly higher ACAIgG and ACAIgM titers, compared with those without CNS-SLE. The results indicate there is a correlation between ACA titers and disease activity. In patients with thrombosis, the titer of ACAIgA is higher, and in patients with CNS-SLE, the titers of ACAIgG and ACAIgM are higher.

Adolescent↗

PubMed2000

[A simple biostatistical method for meta analysis of the data on 2 x 2 table].

Meta-analysis is a method in common use for data analysis in evidence-based medicine. In this paper, based on the Mantel-Haenszel and Peto methods used for Meta-analysis of the data on 2 x 2 table, we put forward a simple calculating method for clinicians. It is useful for Meta-analysis and can be easily applied to analysis of the data from multi-studies in evidence-based medicine.

Biometry↗

PubMed2000

[Effects of silk hydrates on the blood glucose metabolism in rats with experimental diabetes].

Male Wistar rats were divided into two groups by random. One group was injected with streptozotocin(STZ) 30 mg/kg BW via tail vein. Three weeks later, the rats were fed on diet of high fat, high sucrose and high calorie for another 8 weeks. There were 38 rats with impaired glucose tolerance and insulin level higher or equal to the control group selected as the diabetic model group. Another 36 rats not injected with STZ and fed on normal diet were selected as controls. The two groups were divided into two subgroups and fed with normal diet for another 4 weeks. The four subgroups were normal control group, normal +SH group, diabetes control group and diabetes +SH group. The rats in normal +SH group and diabetes +SH group were tube feeding every day with silk hydrate (SH) 1.0 g/kg BW for 4 weeks. The results showed that in the diabetes +SH group, the glucose tolerance, blood lipid and the predictive index of coronary heart disease were significantly improved, but no effect on their blood insulin level. There was no change in the normal +SH group. The results suggested that SH could modulate the metabolism of blood glucose and partly improve the disorder of the serum lipid of diabetic rats.

Animals↗

PubMed2000

[Study on multi-element determination in drinking water by ICP-OES and ICP-MS].

A new method was developed for the determination of twenty-three elements in water samples by ICP-OES and ICP-MS. The detection limits, standard deviations and linear calibration ranges were measured. The sensitivity of the method was excellent and the determination was very fast for various elements including Ca, Mg, Fe, Mn, B, Cr, Si, Zn, Be, Al, V, Co, Ni, Cu, As, Se, Mo, Ag, Cd, Sb, Ba, Tl and Pb. Preconcentration and separation procedures were not required and hence the potential cross contamination was minimized. Recoveries of the standards spiked to natural samples were at the range of 94.5%-116.2%. Besides, the analytical values of standard reference materials obtained by the proposed method were conformed well with the certified values. The accuracy of results was further validated by comparing with the data obtained by using AAS and AFS. The proposed method was applied in the quality study of Shenzhen drinking water. A precise and accurate background data of various trace elements content of the city was obtained.

Calcium↗

PubMed2000

[Mechanism of silk hydrates on modulating the blood glucose metabolism in rats with experimental diabetes].

Thirty eight adult male Wistar rats injected with streptozotocin(STZ) 30 mg/kg BW via tail vein and fed on a diet of high fat, high sucrose and high calorie for 3 weeks and then for another 8 weeks were successfully established as the diabetes model(type II diabetes mellitus). The effects of feeding silk hydrates(SH) for 12 weeks on the activities of insulin receptors and postreceptors were observed. The results showed that: 1) SH greatly improved the glucose tolerance of diabetic rats, but no effect on the secretion of insulin in rats with or without diabetes; 2) Only the low-affinity constant of insulin binding rates(K2) in skeletal muscle cell membranes of diabetic rats fed with SH were obviously increased, the high-affinity binding constant and the number of receptors were not changed; 3) the uptake of glucose in skeletal muscle of diabetic rats fed on SH was significantly increased. 4) SH partly improved the metabolism of serum lipids. The results indicated that SH could modulate the metabolism of blood glucose mainly through the mechanism on the activity of insulin postreceptor.

Animals↗

PubMed2000

[Measurement of content of collagen type IV and laminin in tissue of oral squamous cell carcinoma and its clinical significance].

OBJECTIVE: To investigate the relationship between the content of collagen type IV (ColIV) and laminin (LN) in tissue of oral squamous cell carcinoma and the clinicopathological parameters. METHODS: 30 patients with oral squamous cell carcinoma came into the study, 6 normal mucosa tissue came from patients who underwent orthogathic operations. The extraction solution was prepared by homogenizing of cancer and normal mucosa tissue in extraction buffer. The content of ColIV and LN in tissue of oral squamous cell carcinoma were measured by radioimmunoassay and represented by amount of per milliliter extraction solution. Mode of invasion (MI) was divided into 4 types basing on the relationship between normal and cancer tissue. The results of measurement of content of ColIV and LN were expressed using mean +/- s, whose correlation with clinicopathological parameters was evaluated by using Student t test. RESULTS: The MI classification showed that type I consisted of 4 cases, and type II comprised 12 cases. 5 and 9 cases belonged to type III and type IV respectively. The content of LN and ColIV in tumor tissue were 1.02 +/- 0.11 micrograms/ml and 1.83 +/- 0.21 micrograms/ml respectively, and the content of LN and ColIV in normal tissue were 1.98 +/- 0.23 micrograms/ml and 2.87 +/- 0.45 micrograms/ml respectively. There was significant difference between the content of ColIV and LN in normal and tumor tissue, and the content of ColIV and LN in normal tissue was much higher than that in cancer tissue (P < 0.05, P < 0.01). No relationship was found between the variation of ColIV and LN content and location and pathological grade of squamous cell carcinoma (P > 0.05), but it was found the content of LN and ColIV in patients with neck lymph node metastasis were greater than that in patients without metastasis (P < 0.05). Content of LN and ColIV also showed negative relationship with the MI index. CONCLUSION: The assay of LN and ColIV in tumor might be useful for diagnosis of metastasis of oral squamous cell carcinoma, and moreover, the relationship between ColIV and LN and MI also gives the suggestion that ColIV and LN may play some roles in preventing the invasion of oral squamous cell carcinoma.

Adult↗

PubMed2000

[Comparison of mechanical properties of laser-welded wrought and cast titanium].

OBJECTIVE: This study was aimed to compare the mechanical properties of laser-welded wrought and cast titanium. METHODS: According to relevant reports and clinical demands, the specimens of TA2 were machine milled or cast into certain sizes using LZ centrifuge-vacuum-pressure titanium casting machine. This experiment involved four groups including the laser-welded wrought titanium group, the laser-welded cast titanium group, the wrought titanium group and the cast titanium group. There were 6 complete specimens in each group and the specimens were ultrasonically cleaned with ethyl and distilled water before they were welded with home-made Nd:YAG apparatus, and comparisons of mechanical properties were made among these groups. All tensile specimens were mounted on the Instron universal testing machine to test tensile loads, yield loads and absolute elongations were measured. The cross section of fractured surface was observed under S-2700 Hitachi SEM and Vickers' microhardness values in different areas were detected with AKASHI microhardness tester. RESULTS: It was showed that the tensile load of laser-welded wrought titanium made no difference from that of the original wrought titanium, but the yield load of laser-welded wrought titanium was bigger than that of the original wrought titanium. The tensile load and yield load of cast titanium were slightly bigger than those of wrought titanium. The tensile load and yield load of laser-welded wrought titanium made no statistic difference from those of laser-welded cast titanium. The absolute elongations of cast or welded titanium were lower than those of wrought or non-welded titanium. The fractured surface of cast titanium under SEM appeared lath-like structure and that of welded cast titanium honeycomb-like structure. The honeycomb-like structure of wrought titanium was more obvious than that of laser-welded wrought titanium. The microhardness value of laser-welded cast titanium was slightly bigger than that of laser-welded wrought titanium. CONCLUSION: The mechanical property of laser-welded wrought titanium might be not apparently different from that of laser-welded cast titanium.

Dental Soldering↗

PubMed2000

[An cephalomectric study on craniofacial structures of Uygur adults with normal occlusion in Xinjiang autonomous region].

OBJECTIVE: To study craniofacial structures of Uygur adults with normal occlusion and establish the standard cephalometric values to evaluate the craniofacial soft and hard tissue structures of normal Uygur adults. METHODS: Lateral cephalometric radiographs of 93 Uygur adults with normal occlusion (43 men and 50 women) were evaluated with the same standard. Their age ranged from 18 to 25 years old, and they had normal and well-balanced faces without receiving any orthodontical treatment. The lateral cephalogram of each normal adult was traced digitized and measured by the same computer system, then the indexes of craniofacial structures were analyzed by multifactor cluster analysis. 18 typical items were chosen to analyze the characters of the craniofacial structures of Uygur adults with normal occlusion. At the same time, Bayers discriminant analysis was used to identify and evaluate the cluster results. RESULTS: Uygur adults with normal occlusion were divided into three patterns according to the multifactor cluster analytic results: horizontal tendency pattern (40%), medial pattern (43%) and vertical tendency pattern (17%). When the horizontal tendency pattern was compared with the medial pattern, it showed that the height of S-Go increased (P < 0.05), while the height of ANS-Xi-Pm decreased (P < 0.05); The proportion of S-Go/N-Me increased (P < 0.01). The angle of Ar-Go-Me and Y axis decreased (P < 0.05), which meant that the mandible rotated in the counter-clockwise direction. SN-MP, PP-MP, OP-MP, MP-FH all decreased (P < 0.01), which meant that the SN plane, the PP plane, the occlusion plane and the MP plane all had the trend of hypodivergence. When the vertical tendency pattern was compared with the medial pattern, the height of Ar-Fo decreased (P < 0.01), while the height of ANS-Me increased (P < 0.01); The angle of Ar-Go-Me, Y axis, SN-MP, PP-MP, OP-MP and MP-FH all increased (P < 0.01). These results showed that the mandible rotated in the clockwise direction and the SN plane, the PP plane, the occlusion plane, and the MP plane all had the trend of hyperdivergence. At last, according to the different skeletal patterns, the normal cephalometric values of Uygur adults with normal occlusion were established. CONCLUSION: Significantly craniofacial structure difference exist in the adults with normal occlusion. Therefore, it is necessary to establish the normal cephalometric values of Uygur adults with normal occlusion according to different skeletal patterns.

Adolescent↗

PubMed2000

[Some differences on biological characteristics of Campylobacter jejuni].

Fecal samples from 195 diarrheic patients in different age, rectal and cloacal swabs from 656 normal and diarrheic animals and poultry, 108 visceral materials from the dead animals with diarrhoea were cultured for Compylobacter jejuni. A total of 458 strains of campylobacters (445 strains of C. jejuni, 13 strains of C. coli) were isolated and identified, and some biological characteristics of these strains were observed. Lior's biotyping scheme was used for biotyping 354 strains of campylobacters(253 strains of C. jejuni and 2 strains of C. coli). The results showed the most biological characteristics of these campylobacters accorded with that previously described in the literatures, but it were also found that there were some differences on morphological, cultural, physiological and biochemical characteristics and antibiotic resistances. In these differences, the most main differences were that 48.3% (215/445) of C. jejuni and 23.1% (3/13) of C. coli were resistant to nalidixic acid, and that 1.1% (5/445) of C. jejuni and 7.6(1/13) of C. coli were resistant to cefotaxime. There were relationships between antibiotic resistances and strain sources (P < 0.005). The result of biotyping 352 strains of C. jejuni indicated that biotype I (40.9%) and II (58.2%) were predominant in the bodies of these animals, and there were two biotypes distributed in the body of same animal.

Animals↗

PubMed2000

[Telomerase activity and expression of its RNA component in laryngeal cancer].

OBJECTIVE: Expression of telomerase activity and telomerase RNA component have been reported in various human cancers. In the article, we ascertained whether telomerase activity and hTR changes are characteristic of laryngeal cancer. METHOD: Telomerase activity were examined by telomeric repeat amplification protocol (Trap) and hTR examined by in situ hybridization, in tissue samples from 50 laryngeal cancer, 12 laryngeal polyps, 14 precancerous, 9 normal laryngeal tissue. RESULT: 1. All tissue expressed various levels of hTR. Positive rate of hTR increased with the clinical stage, but no significant correlation was observed, as well as lymph node metastasis. 2. The telomerase activity were detected in samples 39 of the 50 laryngeal cancer(78%). However, in 12 cases of begin lesions only 8.3% (1/12). Telomerase activity was found to have a relationship with the grade of tumor differentiation. Poorly differentiated laryngeal cancer expressed high level telomerase activity. CONCLUSION: Telomerase activity were an early event of laryngeal cancer. It suggests that detection of telomerase activity could be a good diagnostic marker for distinguish cancer from normal cell.

Adult↗

PubMed2000

Effect of coxsackievirus b3 on ion channel currents in rat ventricular myocytes.

OBJECTIVE: To investigate the effects of coxsackievirus B3(CVB3) on ion channel currents in rat ventricular myocytes. METHODS: Rat hearts were isolated with collagenase to acquire single ventricular myocytes, L-type voltage-dependent calcium channel (VDCC) current (I(Ca)), Na+ current (I(Na)), outward potassium current (I(out)), inwardly rectifying potassium current(I(KI)) were recorded using whole cell patch clamp techniques. RESULTS: CVB3 infection increased I(Ca) and I(out), while decreased I(KI); but it had no obvious effect on I(Na). CONCLUSION: The effects of CVB3 an I(Ca), I(out), I(KI) may be one of the mechanisms of myocytes damage and the occurrence of abnormal electroactivities induced by CVB3 infection.

Animals↗

PubMed2000

[The measurement of temperature with Raman scattering spectra of polycrystal (SrNO3)2].

We have developed a new method for the determination of temperature with Raman scattering spectra. The strontium nitrate was chosen as an experiment substance. It has two bands of Raman scattering, and their wavenumbers are 738 and 1,057 cm-1 in 600-1,700 cm-1. We have obtained the intensities of their Stokes and Anti-Stokes scattering, then we have got two temperatures of strontium nitrate according to the formula. The result from the 738 cm-1 scattering band has larger error than that from the 1,057 cm-1. This may account for the noise of the photocounter. This no touch method is fit to measure the temperature of the molecular.

Crystallization↗