Biomedical subjects

L Wang

Publications and source records attributed to L Wang.

At least 577 records · Page 32Linked to original sources

PubMed2001

Analysis of hypermutation of the 5' noncoding region in the BCL-6 gene.

OBJECTIVE: To investigate BCL-6 gene mutations in Chinese populations with B-cell non-Hodgkin's lymphoma. METHODS: Polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing were used to identify mutations in the 5' noncoding region of the BCL-6 gene in a total of 40 cases of diffuse large-cell lymphoma (DLCL) and follicular lymphoma (FL). RESULTS: Nine cases were found to have base substitutions. The incidence of BCL-6 gene mutation and the frequency of single-base changes were approximately 25.7% and (0.56-1.10) x 10(-2)/bp, respectively. CONCLUSIONS: The 5' regulatory region of the BCL-6 gene undergoes frequent somatic hypermutation during lymphomagenesis and the identification of BCL-6 gene hypermutations provides a molecular marker for confirmatory diagnosis of B-NHL.

5' Flanking Region↗

PubMed2001

Alleviation of hypoxic pulmonary vascular structural remodeling by L-arginine.

OBJECTIVE: To explore the effect of L-arginine on hypoxic pulmonary vascular structural remodeling and its possible mechanisms. METHODS: Eighteen Wistar rats were randomly divided into three groups: the hypoxia group, the hypoxia with L-arginine group and the control group. Pulmonary artery mean pressure was evaluated with right cardiac catheterization. Pulmonary vascular structural changes were also observed. Plasma concentration of nitric oxide (NO) was measured via spectrophotometry, and endothelin-1 (ET-1) mRNA expression in pulmonary artery endothelial cells was detected using in situ hybridization. RESULTS: The pulmonary artery mean pressure was significantly high in hypoxic rats than in normal controls (20.33 +/- 2.18 mm Hg vs 15.38 +/- 1.05 mm Hg, P < 0.05). Microstructural and ultrastructural analysis revealed the development of hypoxic pulmonary vascular structural remodeling in the hypoxic rats. Meanwhile, the plasma NO concentration was markedly lower in the hypoxic rats than in controls (P < 0.05). The expression signals of ET-1 mRNA by pulmonary artery endothelial cells of hypoxic rats strengthened obviously. L-arginine ameliorated pulmonary hypertension (16.73 +/- 1.35 mm Hg vs 20.33 +/- 2.18 mm Hg, P < 0.05) as well as pulmonary vascular structural remodeling in the hypoxic rats in association with an increase in plasma NO concentration (P < 0.05) and inhibited ET-1 mRNA expression by the endothelial cells of pulmonary arteries. CONCLUSION: L-arginine might play an important role in the regulation of hypoxic pulmonary vascular structural remodeling and hypoxic pulmonary hypertension. The mechanism is probably related to promoting NO production and, as a result, inhibiting ET-1 mRNA expression by pulmonary artery endothelial cells in hypoxic rats.

Animals↗

PubMed2001

Expression and function of c-kit receptor in bone marrow mononuclear cells of patients with myelodysplastic syndromes.

OBJECTIVE: To determine the expression and function of the c-kit receptor in bone marrow mononuclear cells (BMMNC) of patients with myelodysplastic syndromes (MDS). METHODS: Direct immunofluorescence assay and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect c-kit protein and c-kit mRNA expressions in the BMMNC of 29 MDS patients and 10 normal controls. Cell culture was used to detect the function of the c-kit receptor. RESULTS: c-kit protein expression in the MDS group was significantly higher than that in the control group (8.58% +/- 5.28% vs 3.04% +/- 1.49%, P < 0.05). c-kit protein expression in the refractory anemia (RA) group was significantly lower than that in the RA with an excess of blasts (RAEB)/RAEB in transformation (RAEB-t) group (5.12% +/- 2.13% vs 10.01% +/- 5.07%, P < 0.05). The rate of c-kit protein expression was 32.43% in acute myeloblastic leukemia (AML) cases transformed from MDS (t-AML). c-kit mRNA expression in the MDS group was correlated with c-kit protein expression. Interleukin-3 (IL-3) and erythropoietin (Epo), with or without stem cell factor (SCF), upregulated c-kit protein and its mRNA expression. In the presence of IL-3 and Epo, SCF showed significant stimulating effects on the formation of CFU-GM and BFU-E in semi-solid cultures of normal BMMNC, but had no effects on those of the MDS patients. CONCLUSION: The protein and mRNA expression of the c-kit receptor in the BMMNC of MDS patients were higher than those of normal controls, and the function of this receptor in MDS BMMNC was abnormal.

Bone Marrow Cells↗

PubMed2001

[Influence of focal adhesion kinase (FAK) on the biological behaviors of human hepatocellular carcinoma cells].

OBJECTIVE: To study the effect of reducing FAK expression on the malignant biological behaviors of FAK-overexpressed hepatocellular carcinoma cell line SMMC-7721. METHODS: FAK expression of different hepatocelluar carcinoma cell lines was detected by Western blot analysis. Antisense plasmid of FAK was constructed and transfected into SMMC-7721. RESULTS: SMMC-7721 expressed much more FAK than did hepatocyte line L02. When transfected with autisense FAK, it showed reduced growth rate and colony formation in soft agar, and the number of cells in S phase was reduced by 15%. The adhesion ability of antisense FAK-transfeected cells was also decreased with no change of integrin expression. CONCLUSION: FAK is overexpressed in the human hepatocellular carcinoma cell line SMMC-7721. Reducing the FAK expression can partly reverse the malignant behaviors of the cell line.

Blotting, Western↗

PubMed2001

[A study on cyclooxygenase-2 protein expression in esophageal carcinoma and premalignant lesions].

OBJECTIVE: To investigate cyclooxygenase-2(Cox-2) protein expression in esophageal cancer and precancerous lesions. METHODS: One hundred twenty biopsy specimens from patients with esophageal carcinoma, 113 from patients with esophageal premalignant lesions, 27 from individuals with normal esophageal mucosa and 3 from Barrett's esophagus were examined for Cox-2 protein expression by immunohistochemistry. RESULTS: Cox-2 protein was not observed in normal esophageal squamous and glandular epithelium, hyperplasia from mild to severe dysplasia lesions and carcinoma in situ. Positive Cox-2 expression was found in 4 of 60 specimens of invasive squamous-cell carcinomas, 21 of 30 specimens of esophageal adenocarcinomas and in 3 of 3 Barrett's esophageal tissues. CONCLUSION: The Cox-2 protein expression may be associated with the development of the esophageal adenocarcinomas but not esophageal squamous-cell carcinomas.

Adenocarcinoma↗

PubMed2001

[Carcinoid of trachea and bronchus: a report of 20 cases].

OBJECTIVE: To understand the biologic and clinical characteristics of carcinoid tumor of trachea and bronchus and to find out rational surgical indications and approaches. METHODS: The clinical materials of 20 surgically treated patients with carcinoid of trachea and bronchus were retrospectively analyzed. RESULTS: All but one patient received radical tumor resection. Operative complication occurred in 2 patients. Of the 20 patients, 13 suffered from typical carcinoids (TC) and 7 from atypical carcinoids (AC). Immunochemical staining revealed that both the typical and atypical carcinoids were of neuroendocrine origin. The 5-, 10- and 15-year survival rate of TC patients was 100.0%, 7/8 and 3/4 respectively. Of the 7 patients with AC, 6 had not yet been 5 years after operation but were still alive, and one patient died of remote metastasis 2 years after operation. CONCLUSION: Surgical resection of carcinoid is indicated not only for early cases, but also for patients in stage III a and III b. The age and pulmonary function of the patients are the chief factors determining the surgical approach.

Adult↗

PubMed2001

[Treatment of stage II non-Hodgkin's lymphoma: analysis of 268 patients].

OBJECTIVE: To seek the optimum treatment for patients with stage II non-Hodgkin's Lymphoma (NHL). METHODS: 268 patients with stage II NHL, treated from January 1987 to December 1993, received radiation alone (R-50), radiation plus chemotherapy (R + C - 73), chemotherapy followed by radiation then by chemotherapy (C + R + C - 72), chemotherapy plus radiation (C + R - 61) or chemotherapy alone (C-12). A total of 206 patients was treated with combined treatment. RESULTS: The 1-, 2-, 3-, 4-, 5- and 6-year survival rates were 95.1%, 87.8%, 87.8%, 85.4%, 82.9%, 53.6% in C + R + C group for patients with stage II high grade NHL, which were much better than those in the R group, R + C group and C + R group (P < 0.01). For patients with stage II intermediate grade NHL, the 1-, 2-, 3-, 4-, 5- and 6-year survival rates were 89.3%, 75.0%, 67.8%, 60.6%, 57.1%, 46.4% in the C + R + C group, which were better than those in the R group, R + C group and C + R group (P > 0.05). However, for patients with low grade NHL, the survival rates were similar both in the R group and the combination groups. CONCLUSION: For patients with stage II intermediate and high grade NHL, combination therapy of C + R + C is recommended. Radiation alone can only be used for patients with stage II low grade NHL.

Adolescent↗

PubMed2001

[Second primary lung cancer in laryngeal cancer patients: report on 36 cases].

OBJECTIVE: To discuss the development, treatment and prognosis of a second primary lung cancer in laryngeal carcinoma patients. METHODS: A total of 36 patients with a second primary lung cancer was discovered in 2,182 laryngeal cancer patients. For comparison, a group of 15,541 lung cancers was also reviewed for the presence of a second primary laryngeal cancer. All patients have been followed for over five years. RESULTS: From 1958 to 1999, out of 2,182 laryngeal carcinoma patients, 36 synchronous (3) or metachronous (33) second primary malignancies of the lung were found. This represented 1.65% of all largngeal cancers observed or 45.0% of all the second primary cancers developed. Their pathology was: squamous cell carcinoma (32-88.9%), adenocarcinoma(2-5.6%), small cell carcinoma(1-2.8%) and large cell carcinoma (1-2.8%). The c-TNM stages were: stage I (7-19.4%), stage II (12-33.3%), stage III (9-25.0%) and stage IV (8-22.2%). The 2- and 5-year survival rates were 41.7% and 8.3%, with an average survival of 23 months. The interval from the treatment of the initial laryngeal carcinoma to the development of the new second primary carcinoma of lung ranged from 1 to 14 years, with an average of 44 months. CONCLUSION: Synchronous or metachronous second malignancies of the lung are sometimes encountered in laryngeal cancer patients while the occurrence of a laryngeal second primary following a lung cancer is not observed. The development of the second primary lung cancer is not related to the treatment of the initial laryngeal malignancies. Surgery plus external radiotherapy provides better results than surgery or radiotherapy alone.

Adenocarcinoma↗

PubMed2001

[Research on transparent apinoid enemator].

Transparent apinoid enemator is made of polymethacrylate material. It is composed of external shell, big cover, small cover, liquor drain tube and suspension belt. Lateral surface of the shell has 100-1500 ml volume mark. Liquor drain tube is made of PVC, its inner diameter is 6 mm. The cover can reduce contamination and maintain liquor temperature. The transparent enemator made by us can overcome the shortcomings of non-transparent enamel enemator which has been used for many years.

Animals↗

PubMed2001

Role of beta-adrenoceptor at different stages of bronchial asthma.

OBJECTIVE: To investigate the changes of beta-adrenergic receptor (beta AR) in peripheral lymphocytes and beta 2AR mRNA levels at different stages of bronchial asthma. METHODS: beta 2AR density and beta 2AR mRNA level in peripheral lymphocytes, cAMP and cGMP levels in blood plasma were estimated by radioligand binding assay, radioimmunoassay and RT-PCR. RESULTS: (1) Maximum bound volume (Bmax) and equilibrium dissociation constant (Kd) of beta 2AR of lymphocyte in asthma patients at remission stage were markedly higher than that in normal subjects, while cAMP levels in blood plasma showed no difference. Bmax of beta 2AR and cAMP levels in asthma patients at acute exacerbation stage were significantly lower than that in normal subjects, and Kds between these two groups were not much different. (2) Expression of beta 2ARmRNA in peripheral lymphocytes of asthmatics at remission stage was not significantly different compared with that in normals. CONCLUSIONS: Amount and function of beta AR and beta 2ARmRNA levels are related to asthmatic conditions. Changes of beta AR and beta 2ARmRNA in asthma might rather be a pathological change accompanied by the course of the disease than a primary defect.

Adult↗

PubMed2001

[Studies of mtDNA haplotype polymorphism of Rongcheng population in China].

The loss of one copy of two 9-bp repeats in mtDNA non-coding region V is often found in Asia and Pacific populations. Two hundred and ten samples from Rongcheng county, Shandong province were detected with the deletion frequency of 12.4%. A distribution map of frequencies of mtDNA 9-bp deletion among Asian and Pacific population was made with reference to other published data. Further discussion was made for the hypotheses of affinity and original model of those populations. PCR-RFLP was conducted to obtain the mtDNA polymorphism information in five other mtDNA regions except the 9-bp deletion in 95 samples. Twenty-seven different mtDNA haplotypes were found, and the relationships among these haplotypes have been analyzed by using MEGA2.0 and PHYLIP 3.57. Two new RFLP sites caused by point mutation were also found, which have not been reported in Chinese populations.

Adolescent↗

PubMed2001

[The prognostic research of expression and relationship between Helicobacter pylori of c-met oncogene correlation with gastric mucosal proliferation].

OBJECTIVE: To determine whether there is a relationship between Helicobacter pylori (Hp) and expression of c-met oncogene and proliferating cell nuclear antigen (PCNA) in gastric mucosal lesions, and prognostic significance of gastric carcinomas(GC). METHODS: Expression of c-met and PCNA were investigated in 145 gastric mucosal lesions by using immunohistochemistry. Hp was examined by Warthin-Starry method. RESULTS: For chronic superficial gastritis (CSG), chronic atrophic gastritis and intestinal metaplasia (CAS + IM), dysplasia(DYS), early GC and advanced GC, the positive rates of c-met and PCNA were higher in IM, DYS and GC than in CSG (P < 0.05). Expressions of c-met and PCNA increased with the increasing proliferation of gastric mucosa, in rank correlation test, they had a close relationship (P < 0.01). Expressions of c-met and PCNA were correlated significantly with histologic type, serosal invasion and lymph node metastasis. In particular, the expression of c-met and PCNA were significantly higher in Borrmann type 4 GC, type 3 GC and type 1, 2 than in early GC(P < 0.05). By rank correlation test, c-met and PCNA have a close relationship (P < 0.001). Expressions of c-met of Hp positive were higher than Hp negative in intestinal GC (P < 0.05). Expressions of c-met were correlated significantly with Hp positive in CAG + IM, DYS and GC. The survival rate of patients with Hp infection was significantly poorer than that of patients with Hp non-infection. CONCLUSIONS: The expression of c-met may be is associated with proliferation and malignant transformation of gastric mucosa. These results suggest that expression of c-met may be a new prognostic factor in gastric carcinoma. Hp infection and expression of c-met may be associated with in proliferation and malignant transformation of gastric mucosa. Hp infection is associated with prognosis of gastric carcinoma.

Cell Proliferation↗

PubMed2001

[Epidemiological investigation on incidence of bronchial asthma in urban population of Shenyang].

OBJECTIVE: Try to find out asthma incidence in urban population of Shenyang. METHOD: From December 1998 to June 1999, 24 176 residents (11 955 male and 12 221 female persons) living in two residential districts from an industrial and a cultural region were selected as subjects of epidemic investigation by random sampling. The subjects were asked questions concerning the epidemic investigation. The lung functions were measured for subjects suspicious for asthma. RESULTS: 299 cases (102 male and 197 female) were diagnosed as asthma. The incidence of asthma was 1.24% (male 0.85% and female 1.61%). The female incidence of asthma was significantly higher than that in male (P < 0.01). Of the asthma patients, 80 cases (26.76%) were found with heredity background in their families; and 73 cases (24.41%) were found complicated with COPD. CONCLUSION: The investigation basically reflected the true condition of asthma incidence in urban population of Shenyang.

Adolescent↗

PubMed2001

[Accelerated hyperfractionation radiation therapy combined with chemotherapy for non-small cell lung cancer complicated with superior vena cava syndrome].

OBJECTIVE: This retrospective study was done to evaluate the patient's tolerance and effect of accelerated hyperfractionation radiation therapy in the treatment of superior vena cava syndrome (SVCS) caused by non-small cell lung cancer (NSCLC). METHODS: Thirty-four NSCLC patients complicated with SVCS were treated between January 1992 and September 1996. Their ages ranged from 36-78 years (median 57). There were 30 (88.2%) male and 4(11.8%) female patients. Dyspnea (67.6%) and facial swelling (52.9%) were the two most common symptoms. Engorgement of neck veins (38.2%) and dilated chest wall veins (28.5%) were the most common physical findings. According to their pathological diagnosis, there were 17(50%) squamous cell carcinomas, 14(41.2%) adenocarcinomas, 2(5.9%) mixed squamous and adenocarcinomas and 1(2.96%) poorly differentiated carcinomas. By thoracic CT scans, a mass was most commonly found in the right upper lobe and the upper mediastinum. For these patients, chemotherapy IEP or IAP (IFO 2.0 g d1-4, DDP 40 mg d1-3, Vp-16 0.1 g d1-3 or ADM 50 mg d1) was given first. Twenty-four to 72 hours after chemotherapy, accelerated hyperfractionation radiation therapy was started to deliver to the primary tumor and the metastatic mediastinal lymph nodes, a tumor dose of 30 Gy/20 fx/2 wk followed by a boost to 36-40.8 Gy/30-34 fx/3-3.5 wk. Diuretics, steroids and dehydrating agents were concomittantly prescribed during the radiation therapy. RESULTS: Relief of SVCS to various degrees was noted in all patients. CR, PR and MR rates were 20.6% (7/34), 50% (17/34) and 29.4% (10/34), respectively. The median survival was 12 months (4-26 months). The 1-2 year actuarial survival rates were 58.1% and 18.2% Except radio-esophagitis in different degrees, no other severe complications were observed. CONCLUSION: The fraction and total dose of radiotherapy are tolerable in this accelerated hyperfractionation trial. Radiation therapy combined with chemotherapy gives similar results as non-surgery for stage III NSCLC. No significant difference in the survival rates of the various histological types is observed.

Adenocarcinoma↗

PubMed2001

[Diagnosis and surgical treatment of double primary lung cancer].

OBJECTIVE: To arrive at a rational diagnosis and effective surgical treatment of double primary lung cancer. METHODS: Thirty-four patients with double primary lung cancers were operated in our department from 1977 to 1999. RESULTS: Twenty-two lesions were metachronous and 12 synchronous. Among the patients with metachronous second primary lung cancer, 10 were treated by lobectomy, 11 by partial resection and one was explored only. The morbidity, mortality and 5-year survival rates were 13.6%, 4.6% and 25.0%, respectively. Among the synchronous double primary lung cancer patients, 2 were treated by lobectomy and 2 by pneumonectomy and the others by partial resection at least for one tumor. There was no morbidity or mortality, and the 5-year survival rate was 14.3%. CONCLUSION: Because of the low detection rate of double primary lung cancer, preoperative diagnosis, differential diagnosis and postoperative follow up must be paid with due attention. Conservative operation and incomplete lymph node dissection, being the chief reasons of poor outcome, should be stressed.

Adenocarcinoma↗

PubMed2001

Treatment of traumatic brain injury in female rats with intravenous administration of bone marrow stromal cells.

OBJECTIVE: To study the effect of bone marrow stromal cells administered intravenously to female rats subjected to traumatic brain injury. METHODS: We injected marrow stromal cells harvested from male rat bone marrow (n = 24) into the tail vein of the female rat (n = 8) 24 hours after traumatic brain injury; the rats were killed at Day 7 or 14 after treatment. The neurological function of the rats was evaluated using the rotarod test and the neurological severity score. The distribution of the male donor cells in brain, heart, lung, kidney, liver, muscle, spleen, and bone marrow of the female recipient rats was measured by identifying Y chromosome-positive cells using fluorescent in situ hybridization. RESULTS: We found that marrow stromal cells injected intravenously significantly reduced motor and neurological deficits compared with control groups by Day 15 after traumatic brain injury (P < 0.05, analysis of covariance for repeated measures). The transplanted cells preferentially engrafted into the parenchyma of the injured brain and expressed the neuronal marker NeuN and the astrocytic marker glial fibrillary acidic protein. Marrow stromal cells were also found in other organs in female rats subjected to traumatic brain injury without any obvious adverse effects. CONCLUSION: These data suggest that the intravenous administration of marrow stromal cells may be a promising therapeutic strategy that warrants further investigation for patients with traumatic brain injury.

Animals↗

PubMed2001

[Cox multivariate analysis of prognosis and proposal on a modified staging system of thymoma].

OBJECTIVE: To investigate the clinicopathologic features, prognostic factors and propose a new modified staging criteria for thymoma. METHODS: The data of 159 patients operated for thymoma collected were retrospectively analyzed as to their prognostic factors and criteria of clinical staging through comparison of survival rates by the actuarial method, Log-rank and Cox multivariable model. RESULTS: Thorough resection (OR = 2.10), and extent of tumor invasion (OR = 1.73) were the most important prognostic factors. Tumor with peritumoral adhesion and absence of a complete capsule but without external invasion belonged to the criteria of stage II (II a). According to the prognosis and state of resection, lesions with obvious peritumoral invasion into the nearby organs but were thoroughly resected belonged to stage II (II b) and those incompletely resected belonged to III a. The unresectable lesions belonged to III b. CONCLUSION: According to the Cox prognostic multivariable model, the criteria of clinical staging of thymoma are defined as: Stage I-completely encapsulated non-invasive tumor without tight fibrous adhesions to the surroundings. Stage II a-only capsular invasion or capsule incomplete or with tight fibrous adhesions to the surroundings. II b-invasion into the surrounding fatty tissue, pleura, partial pericardium or lung, Stage III a-invasion into the great vessels, heart, trachea or hilus, which are resected with difficulty, or only palliatively. III b-extensive invasion into the nearby organs, and resection is impossible. Stage IV a-pleural or pericardial dissemination, IV b-lymphatic or hematogenous metastasis.

Adolescent↗

PubMed2001

[Palliative irradiation combined with chemotherapy for lung cancer with brain metastasis].

OBJECTIVE: To evaluate to effects and complications of palliative irradiation combined with chemotherapy for lung cancer with brain metastasis. METHODS: Eighty-two non-small cell lung cancer with brain metastasis were treated, of whom 48 had extracranial metastasis simultaneously. All patients received chemotherapy (Teniposide and cis-platin) prior to and also after radiotherapy. The multiple-intracranial metastasis patients received whole brain radiation therapy to a dose of 33-39 Gy/11-13 fx. The others who had single intracranial lesion received whole brain irradiation of 30 Gy/10 fx and a boost of 15 Gy/5 fx. RESULTS: The overall 1- and 2-year actuarial survival rates were 46.7% and 6.7%. For patients with brain metastasis and extracranial lesions, the 1- and 2-year survival rates were 32.4% and 4.4%. For patients with intracranial metastasis only, they were 61.2% and 8.8%, respectively (P = 0.003). The median survival of these two groups were 8 and 12 months. There was no significant correlation between the survivals rate and the histological type or the number of intracranial metastasis. No severe complications were observed during the treatment and follow-up. CONCLUSION: The regimen of combined chemotherapy with radiotherapy is effective for lung cancer with brain metastasis. The survival rate of patients with intracranial metastasis only is obviously higher than those with multiple extracranial lesions in addition to brain metastasis.

Adult↗