Biomedical subjects

J Gao

Publications and source records attributed to J Gao.

At least 163 records · Page 9Linked to original sources

PubMed2000

[Penetrating wounds of the heart: analysis of 56 patients].

OBJECTIVE: To assess the management of penetrating cardiac injuries. METHODS: 56 patients with penetrating wounds of the heart were studied retrospectively. The study lasted for 11 years. RESULTS: Stab wounds accounted for 89.3% of the 56 patients. 56 patients underwent thoracotomy. Preoperative infusion was less than 1,000 ml in 68% of the patients. Preoperative pericardiocentesis was done only in 2 patients, of whom one was false negative. Four patients with cardiac arrest soon after arrival were subjected to emergency thoracotomy; three survived. After the operation, 2 patients died of associated abdominal injuries and failure of cerebral resuscitation. The overall survival rate was 96.4%. CONCLUSIONS: Early diagnosis and prompt thoracotomy are essential to the treatment of penetrating cardiac injuries. Preoperative massive transfusion and pericardiocentesis are not advocated.

Adolescent↗

PubMed2000

Effect of extensive excision of burn wound with invasive infection on hypermetabolism in burn patients with sepsis.

OBJECTIVE: To evaluate the effect of extensive excision of invasive burn wound infection on hypermetabolic response in burn patients with sepsis. METHODS: Eight patients with major burn, complicated by invasive burn wound infection and sepsis, were consecutively admitted to our hospital from September 1997 to October 1998. Resting energy expenditures (REEs) were monitored by means of cardiorespiratory diagnostic system (Medical Graphics Corporation, USA) at patients' bedside. Plasma concentration of IL-6, IL-8, TNF-alpha, and LPS were assayed before and after surgical intervention and at the time when the patients' vital signs became stable. Correlation analysis between REEs and IL-6, IL-8, TNF-alpha, and LPS were made, respectively. RESULTS: A total of 8 treated patients survived. Values of REE before surgical intervention were significantly higher than those after surgical intervention (P < 0.01), and when patients' vital signs became stable the values were significantly lower than those after surgical intervention (P < 0.01). The plasma concentrations of IL-6, IL-8, TNF-alpha, and LPS after excision of invasive burn wound infection were significantly lower than those before surgical intervention (P < 0.05). The lowest levels of these inflammatory mediators were observed when the conditions of patients became stable, and the values were significantly lower than those before surgical intervention (P < 0.001). There was a significant positive correlation between REE level and respective values of plasma IL-6, IL-8, TNF-alpha, and LPS (P < 0.01). CONCLUSIONS: It seemed that the extensive excision of invasively infected burn wound in patients with major burn should be performed as early as possible to reduce an increased release of inflammatory mediators and to control the hypermetabolic response during sepsis.

Adolescent↗

PubMed2000

[Survival analysis after kidney transplantation in 1,180 cadaveric graftings].

OBJECTIVE: To analyze the outcome of twenty-two years of cadaveric kidney transplantation and the predict factors impacting on graft survival. METHODS: The data of 1,180 cadaveric kidney graftings in 1,039 patients between October of 1977 and June of 1999 were summarized by calculation of patient and graft survival rates using Kaplan-Meier product limit estimates. 13 factors that may influence on graft survival were analyzed by the log-rank and Cox model. RESULTS: The total of 1-, 5-, 10-, 15-, and 20-year patient survival rates were 93.02%, 80.25%, 67.86%, 65.34% and 65.34%, and the corresponding graft survival rates 88.6%, 68.3%, 43.8%, 43.8%, and 32.8%, respectively. Graft half-life was (13.98 +/- 0.96) years. The longest survivor was 22 years after cadaveric kidney transplantation. The quality of life after grafting in 835 alive patients was improved apparently; 95% of them had a normal graft function and 85% returned to work. The result of multivariable analysis using Cox model showed that 8 factors of patient's age, grafting time, pretransplant blood transfusion, cold ischemia time, delayed graft function, time of normal graft function, immunosuppressive regimen, and acute rejection were very important to affect the graft survival. CONCLUSION: Cadaveric kidney transplantation is a successful and effective method to rescue the patients with end-stage renal disease.

Adolescent↗

PubMed2000

[Simultaneous pancreas-kidney transplantation for the treatment of type I diabetes with end-stage renal disease].

OBJECTIVE: To demonstrate whether simultaneous pancreas-kidney transplantation is practical for the treatment of Type I diabetes with end-stage renal disease. METHODS: Eight cases of combined pancreas-kidney transplantation were performed in our institute. The age ranged from 35 years to 48 years (average 43.46 years). All cases were diagnosed as type I diabetes with end-stage nephropathy, two cases with blindness due to retinopathy. The case history ranged from 2 years to 22 years. Pancreas allograft was placed in the right iliac fossa with pancreas exocrine drainage to bladder, whereas renal allograft the in left iliac fossa. Initial immunosuppression regimen is quadruple. RESULTS: Seven patient could be insulin free after transplantation, with normal fasting blood glucose. One patient received insulin treatment for 40 days after operation. One patient survived 1 year and 9 months after transplantation with normal functioning pancreas allograft and kidney allograft. Four patient survived 2 months with normal allograft function. Fasting blood glucose was between 4.5 and 6.2 mmol/L; Cr was between 53 and 106 micromol/L. Diet control was not necessary. Two patient died of encephalorrhagia, and 1 pancreatic vascular thrombosis and necrotic pancreatitis. CONCLUSIONS: Combined pancreas-kidney transplantation is feasible to treat type I diabetes with end-stage nephropathy. Functional pancreas allograft could be procured in the present condition. Pancreatic exocrine is drained to bladder. The diagnosis of acute rejection could be made earlier by detecting urine amylase. Heparin should be added in order to prevent pancreatic thrombosis.

Adult↗

PubMed2000

[MMF and CyA in the prevention of early acute rejection after renal transplantation].

OBJECTIVE: To investigate the effect of MMF and low dose CyA on the prevention of early acute rejection after renal transplantation. METHODS: 146 patients with kidney transplantation were analyzed retrospectively from December 1997 to January 1999. These patients were divided into two groups according to the immunosuppressive regimen: Aza group (78 patients) and MMF group (68 patients). All patients met the following criteria: HLA mismatch </= 3 loci, lymphocytes toxicity test < 10%, PRA < 20% for second or third transplantation, warm ischemia time 5-11 minutes, and cold ischemia time 3-24 hours. RESULTS: There were 24 patients with acute rejection episodes (30.77%) in the Aza group; and 10 patients (14.71%) in the MMF group, (P < 0.05). The dosage of CyA and blood concentration of CyA were significantly different; 6.00 +/- 1.21 mg x kg(-1) x d(-1) and 286.00 +/- 20.02 microg/L in the Aza group; 4.00 +/- 1.14 mg x kg(-1) x d(-1) and 204.00 +/- 20.18 microg/L in the MMF group (P < 0.001). CONCLUSIONS: MMF with low dose CyA based triple regimen could prevent the acute rejection episodes effectively at the early period of post transplantation. This triple regimen can reduce the acute rejection episodes by 50%. To some extent, low dose CyA may avoid nephrotoxicity. The long-term effect of this regimen on allograft is still needed to observe.

Adolescent↗

PubMed2000

[Hostility behavior as risk factor of coronary heart disease].

OBJECTIVE: To explore the relationships between hostility, and the risks of coronary-prone behavior and the clusters of unhealthy behaviors in individuals with different levels of hostility. METHODS: A cross-sectional study was carried out among 1 010 male employees from two factories in Beijing Capital Steel and Iron Company in 1997. Data on major risks of cardiovascular, other social-demographic factors and levels of hostility by Cook-Medley Scales were collected. RESULTS: Body mass index, amounts of cigarette smoking and alcohol drinking were significantly increased (P < 0.01) with a characteristic of reduced social support from one's colleagues, when individual's level of hostility increased. In addition, less years of education, higher prevalence of other chronic diseases (P < 0.05) and clustering of various unhealthy behaviors were found related to the increase of individual's hostility. The odds ratio in the group with highest hostility was 2.37 times higher than in the lowest one, after confounding effects from age, blood pressure, education level, status of chronic disease and social support being adjusted. No significant differences on both systolic and diastolic blood pressures among groups with different levels of hostility were discovered. CONCLUSION: The association between hostility, coronary-prone risk behavior and cluster of unhealthy behaviors suggested that hostility might increase the risk of coronary heart diseases through affecting individual's behavior.

Adolescent↗

PubMed2000

[Different susceptibility of cell lines to thymidine kinase/ganciclovir-mediated killing effect and the way of cell death].

OBJECTIVE: To investigate the mechanism of variability of herpes simplex virus (HSV) thymidine kinase (TK)/ganciclovir (GCV)-mediated suicide effect obtained in three different cell lines and the ways in which this system-mediated cell killing occurs. METHODS: Recombinant retroviral vector expressing HSV-TK was transduced into three cell lines known with different growth rate (PC-2, PC-7 and LLC-PK1). The doubling time of the transduced and parental cells was calculated. MTT method was used to detect the concentration of GCV at which cell growth was inhibited by 50% (IC(50) value). Cell cycle was analyzed by flow cytometry. Necrosis or apoptosis of cultured cells and/or xenografts was observed under light and electron microscope, and by in situ apoptosis detection. RESULTS: The doubling time of the three parental cell lines was (31.2 +/- 0.1) h, (48.3 +/- 0.1) h, and (53.9 +/- 0.1) h, separately. The IC(50) values of their HSV-TK-transduced cell lines to GCV were (0.73 +/- 0.12) micromol/L, (0.93 +/- 0.16) micromol/L and (1.22 +/- 0.06) micromol/L, respectively and the IC(50) value was correlated with the cell doubling time. Flow cytometry revealed S arrest. The majority of cells under treatment of GCV displayed swelling and collapse, but very few cells showed apoptosis. Large areas of necrosis were observed in the xenografts. CONCLUSIONS: The cells with high growth rate are more susceptible to HSV-TK/GCV-mediated killing effect. Necrosis is the main way in which cells of the three HSV-TK-transduced cells lines die.

Animals↗

PubMed2000

[Loss and inactivation of PTEN/MMAC1/TEP1 gene in lung cancer].

OBJECTIVE: The recently identified PTEN/MMAC1/TEP1 gene is the first tumor suppressor encoding a phosphatase, which mutated in multiple tumors. Our research aims to detect loss of heterozygosity and inactivation of PTEN in lung cancer. METHODS: 24 lung cancer fresh samples paired with normal tissue, 18 archival paraffin-embedded sections of small cell lung cancer (SCLC) were included. For 24 fresh samples, PCR-LOH was used to detect Loss of heterozygosity (LOH) in or near PTEN loci. In situ hybridization, Western blot and or immunohistochemistry were proceeded for mRNA and protein expression of PTEN in lung cancer samples. Southern, Northern and Western blot were done to exam PTEN abnormality in one NSCLC and three SCLC cell lines. RESULTS: Among these 24 fresh samples PTEN LOH was detected in 11 out of 24 cases (45.8%) and 6 cases had no PTEN mRNA and protein expression. Results in situ hybridization were in conformity with that of immunohistochemistry/Western blot in our research. No protein expression was detected in 8/18 (44%) archival paraffin cases of SCLC. Southern, Northern and Western blot confirmed homozygous deletion in one SCLC cell line. CONCLUSION: Lung cancers had LOH and inactivation of PTEN.

Adenocarcinoma↗

PubMed2000

[Effects of high-affinity nerve growth factor (NGF) receptor gene on NGF-induced differentiation of neuroblastoma cell line].

OBJECTIVE: To study the effects of transfection of high-affinity nerve growth factor receptor gene (trkA) on NGF-induced differentiation of human neuroblastoma cell line IMR-32. METHODS: The recombinant retrovirus vector containing exogeneous trkA gene was constructed and packed by PA317 packaging cell line. The neuroblastoma cell line IMR-32 was transfected by virus containing supernatant. The transformant cell line was confirmed by Southern blot and RT-PCR techniques. The NGF was used to induce cellular differentiation of the transformant cells. RESULTS: The trkA gene was successfully transferred and expressed in the neuroblastoma cells. After NGF treatment, the transformant cells displayed apparent neuron-like differentiation morphologically, and a slower rate of cell growth (MTT value 0.028 +/- 0.003) compared with original cell line (0.258 +/- 0.017) and empty virus transformed cell line (0.237 +/- 0.011). The cells remained in differentiated status after withdrawing the NGF from the medium. The transformant tumor cells rarely formed colonies in soft agar and failed to form tumor in nude mice. CONCLUSION: Restoration of high-affinity NGF receptor (trkA) expression in neuroblastoma cells could induce non-reversal differentiation. The trkA might be the important factor during NGF-induced differentiation of neuroblastoma cell.

Animals↗

PubMed2000

[Experimental study of daicong solution on brain M receptor in dementia model of aged rats].

OBJECTIVE: To explore the effect of Daicong Solution (DCS) on M receptor in brain of aged rat model of dementia. METHODS: The effects of DCS on M receptor in brain of dementia model of learning and memory function hindrance were observed, the basal nuclei were ruined by destroying bilateral electrolytic method in 22-month-old rats. RESULTS: Significant difference was shown in comparing the M receptor in the two groups treated by different dosages of DCS with that in the model control group (P < 0.01), significant difference also displayed in comparison of the DCS treated groups and Naofukang treated group (P < 0.01). CONCLUSION: DCS has marked effects in elevating the number and affinity of M receptor in brain of aged rat dementia model and could improve its learning and memory function, the effect was superior to that of Naofukang.

Aging↗

PubMed2000

[Studies on the effect-increasing components for molluscacides in nut of Areca catech L].

OBJECTIVE: To investigate the effect-increasing action of Areca catech for molluscacide. METHOD: Experiments were conducted on the effect-increasing components isolated from the dry nut of A. catech. RESULT: Arecoline has been proved the most effect-increasing component. CONCLUSION: When used with SPA arecoline could reduce markedly the doses of the two agents.

Animals↗

PubMed2000

[Relationship between the ultrastructural characteristic of coal dust and its toxicity].

To study the relationship between the ultrastructural characteristic of coal dust and its toxicity, we compared two types of coal dusts which damaged alveolar macrophages(AMs) concerning with the coal dusts ultrastructural characteristic by using microscopy and biochemical techniques. The results showed that coal dusts damaged not only AMs plasma and lysosomal enzymes but also in ultrastructure. The coal dust in Nanpiao mine had a sharp form, fragile texture and a structure putting in order. It was concluded that: (1) the toxicity of coal dust in Nanpiao mine was higher than in Kailuan mine and which was related to the ultrastructural feature of the coal dusts; (2) the AMs injury degree by coal dusts was more and more serious with the duration of exposure to coal dusts.

Animals↗

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

[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

[Study on the rule of solvent strength in reversed-phase liquid chromatography].

Based on the physical meanings of Z (total moles of the released solvent at the contact region between solute and stationary phase), and j(the slope of the linear plot of lg I versus Z, a constant relating to the affinity of organic solvent to the stationary phase) of stoichiometric displacement model for retention (SDM-R) of solute in liquid chromatography(LC), both Z and j could be employed to characterize solvents, therefore, Z value only can be used as a characterization parameter for fixed solute and stationary phase. However, the parameter j is independent of solutes. As long as phase is given, j can be employed as a new characterization parameter of organic solvent strength in LC. With the homologues of methanol, ethanol and n-propanol as organic solvents in mobile phase and n-alkylalcohols as solutes, both the SDM-R and Snyder's empirical equation were tested, and compared with the corresponding parameters obtained from Snyder's empirical equation. With S [the slope of the linear plot of lg k' (k' is capacity factor) vs psi(volume fraction of organic solvent in mobile phase)] and lg kw0(the intercept of this plot), it was found that the two linear plots with the SDM-R, lg k' vs the composition of mobile phase and lg I vs Z were better than the corresponding plots with Snyder's empirical equation. The results indicate that Z, lg I and j decrease with the increase in the molecular size of the organic solvent of the homologue. This fact indicates that the solvent strength in LC depends on the size of solvent molecules. And the greater the solvent molecules, the stronger the solvent strength is. Furthermore the solvent strength was found to follow homologous rule. The j value may become a new parameter for the characterization of organic solvent strength in LC.

Chemical Phenomena↗

PubMed2000

Polymorphism of angiotensin-converting enzyme gene and genetic susceptibility to asthma with familial aggregation.

OBJECTIVE: Angiotensin-converting enzyme (ACE) plays a key role in the metabolism of angiotensin II (AT II) and inactivation of bradykinins and tachykinins, which are potent bronchialconstrictors and mediators of inflammation asthma, and ACE is heavily expressed in the lungs. An insertion-deletion (D/I) polymorphism of ACE gene has been shown to be associated with levels of ACE. We investigate whether the polymorphism of ACE gene is associated with asthma and bronchial responsiveness. METHODS: A case-control study was carried out in 50 asthmatics, 7 families with at least 2 asthmatic individuals, and 50 healthy subjects. The insertion/deletion (I/D) polymorphism of ACE gene was amplified by polymerase chain reaction (PCR). Methacholine brocho-provocation and pulmonary function tests were performed in all asthmatics. RESULTS. There was an higher gene frequency of DD genotype of ACE gene in asthmatic subjects and families individuals compared with healthy subjects (46%, 53% vs 16%, P<0.05; odd ratio 4.98). An- higher prevalence of DD genotype of ACE was in patients with bronchial hyperresposiveness (BHR) (67% vs 33%, P<0.05; odd ratio 3.8). Accordingly, the mean values of FEV1% and FEV1/FVC were higher in asthmatics carrying non-DD alleles than patients with DD genotype (73.78% vs 56.56%, P<0.05, 79.19% vs 69.29%, P<0.05, respectively). CONCLUSION: These results suggested that DD allele of ACE genotype was significantly involved in genetic susceptibility to asthma. DD genotype of ACE might be a risk factor for the degree of airway obstruction, it could also be implicated in pathogenesis of bronchial hyperresponsiveness.

Adolescent↗

PubMed2000

[Changes of p16 gene, cyclin D1 gene, and pRb protein in human pancreatic adenocarcinoma cell lines].

OBJECTIVE: To investigate the abnormalities of the relative factors of pRb-p16 cell regulatory pathway in pancreatic adenocarcinoma. METHODS: Five strains of human pancreatic adenocarcinoma cell lines were analysed by PCR and single-strand conformation polymorphism (SSCP) for homozygous deletion and mutation of the p16 gene, respectively. The gene amplification of cyclin D1 was detected by Southern blot analysis and the protein expression of pRb gene was examined by Western blot analysis. RESULTS: Homozygous deletion of exon 1 were found in two cell lines and no mutation was found within exon 1 and exon 2 in five cell lines. Cyclin D1 gene amplification was observed in one cell line and all of the five cell lines showed hyper-phosphorylated pRb protein. CONCLUSION: These findings have demonstrated that there are abnormalities of pRb-p16 regulatory pathway in pancreatic adenocarcinoma cell lines, revealing the alteration of the p16 and cyclin D1 genes.

Adenocarcinoma↗

PubMed2000

[Studies on the stable integration and expression of IL-2R alpha gene in CHO cells and it's applications].

OBJECTIVES: To establish a novel bioassay method for quantitative analysis of human IL-2 based on the specific binding of Interleukin-2 receptor alpha subunit (IL-2R alpha) with IL-2. METHODS: Southern blot hybridization was first used to detect the stability of integration of recombinant secretive IL-2R alpha (rsIL-2R alpha) gene into the genome of highly expressed cell line reported elsewhere; the apparent Mr of the rsIL-2R alpha was then determined by using Western blotting; finally, a receptor-antibody sandwich ELISA method has been established for quantitative analysis of IL-2. RESULTS: (1) Stable integration of rsIL-2R alpha gene into the genome of #17 CHO cell line has been identified; (2) the apparent Mr of rsIL-2R alpha was approximately 40,000; (3) linear range of the standard curve obtained from the receptor-based ELISA fell between 31.25-500 U of IL-2 (r = 0.9995). The slop of the standard curve decreased significantly when IL-2 was pre-incubated with goat anti-IL-2 antibody IgG (P < 0.01). CONCLUSIONS: An IL-2R alpha-based IL-2 ELISA has been established for laboratory and clinical use with advantages of accuracy, specificity and simplicity over other conventional bioassays for IL-2 detection.

Animals↗