Biomedical subjects

X Liu

Publications and source records attributed to X Liu.

At least 649 records · Page 36Linked to original sources

PubMed2000

[The expression of RAR beta mRNA in rat tongue carcinogenesis].

OBJECTIVE: To elucidate the relationship between the expression of nuclear retinoic acid receptor beta (RAR beta) mRNA in oral carcinogenesis and squamous cell aberrant differentiation. METHODS: A total of 69 rat tongue carcinogenesis specimens induced by 4-nitroquinoline-1-oxide (4NQO) were detected for RAR beta mRNA by in situ hybridization. RESULTS: With the progress of tongue carcinogenesis and epithelium cell disdifferentiation, the expression of RAR beta mRNA was down-regulated. The positive rate of RAR beta mRNA in normal, hyperplasia, mild-moderate dysplasia, severe dysplasia, in situ carcinoma and squamous cell carcinoma was 100.0%, 87.5%, 75.0%, 72.2%, 45.5% and 18.8%, respectively. CONCLUSIONS: The down-regulation of RAR beta mRNA may be associated with the epithelium cell aberrant differentiation and may be an important molecular mechanism of oral carcinogenesis.

4-Nitroquinoline-1-oxide↗

PubMed2000

[Experiment study of guiding bone tissue regeneration by frozen homologous periosteum].

OBJECTIVE: Explores the feasibility of guiding bone tissue regeneration by frozen homologous periosteum. METHODS: Rabbit's cranial periosteum was taken and refrigerated. In thirty-one white Japanese big ear rabbits, defects of the mandible were created. Defect at one side was covered with the membrane, another side not. The rabbits were sacrificed on four, eight, twelve, sixteen weeks. Specimens were examined by naked eye, X-ray, and histology. RESULTS: The frozen homologous periosteummet the requirement of guiding bone tissue regeneration There was no rejection, and could be kept 8 for 12 weeks in the body. It had the favorable efficacy of obstructing the fiber tissue from filling into bone defects and had an efficacy of guiding bone tissue regeneration. CONCLUSIONS: Frozen homologous periosteum is a perfect guiding bone tissue regeneration membrane.

Animals↗

PubMed2000

[Telomerase activity in rat tongue carcinogenesis].

OBJECTIVE: To detect the telomerase activity in rat tongue cancer and precancerous lesions and to investigate the possibility of telomerase as oral cancer biological marker. METHODS: A total of 69 rat tongue carcinogenesis specimens induced by 4-nitroquinoline-1-oxide (4NQO) were examined for telomerase activity by PCR-telomeric repeat amplification protocol (TRAP) silver staining and ELISA. RESULTS: Sequential increase in telomerase activity in tongue carcinogenesis was found. The positive rate of telomerase in normal, HP, mmDP, sDP, ISC and SCC was 0.0%, 12.5%, 25.0%, 66.7%, 72.7% and 93.8%. CONCLUSIONS: Telomerase may be a tumor specific gene marker, and may play an important role in early diagnosis and treatment of oral cancer.

4-Nitroquinoline-1-oxide↗

PubMed2000

[Clinical study on treatment of advanced non-small cell lung cancer with Chinese herbal medicine combined with synchronous radio- and chemotherapy].

OBJECTIVE: To explore the effect of applying Chinese herbal medicine according to Syndrome Differentiation of TCM combined with synchronous radio- and chemotherapy (combination therapy) in treating advanced non-small cell lung cancer (NSCLC). METHODS: The 56 patients in the group A were treated with combination therapy, and the 44 patients in the group B treated with synchronous radio- and chemotherapy, while the 34 patients in the group C treated with non-synchronous radio- and chemotherapy. The efficacy of treatment in the three groups were observed and compared. RESULTS: The immediate effective rate in the A, B, C groups was 87.5%, 84.1% and 55.9% respectively, that in the group A and B was better than that in the group C (P < 0.01). The median survival time in the three groups was 16.4, 11.8 and 10.6 months respectively. The 2-year and 3-year survival rate in the group A were markedly higher than those in the group B (P < 0.05), moreover, the clinical symptoms, Karnovsky scoring and immune function were obviously improved in the group A (P < 0.05, P < 0.01). CONCLUSION: Effect of the combination therapy is superior to that of synchronous radio- and chemotherapy alone in improving immune function, elevating quality of life and prolongating survival time of patients with NSCLC.

Adenocarcinoma↗

PubMed2000

[Experimental study on effect of folium Ginkgo biloba in treating pulmonary interstitial fibrosis in rats].

OBJECTIVE: To evaluate the therapeutic effect and mechanism of folium Ginkgo biloba (FGB) in treating pulmonary interstitial fibrosis (PIF) induced by bleomycin in rats. METHODS: PIF models of bleomycin-A5-induced pulmonary fibrosis were established in rats, they were treated by Bailuda, a preparation of FGB, and the pathological changes, collagen protein level, nuclear factor kB(NF-kB) activity, transforming growth factor beta (TGF-beta) mRNA expression and protein level of the lung tissue were measured. RESULTS: In the Bailuda treated group after treatment, amelioration of the pulmonary alveolitis and fibrosis were shown in pathological section (P < 0.05) and collagen protein content was lesser (P < 0.01) as compared with those in the model control group. After 1 week of Bailuda treatment, the NF-kB activity of pulmonary alveola macrophage lowered by 47.3%, and levels of TGF-beta mRNA expression and protein were all decreased (P < 0.05). CONCLUSIONS: Bailuda has definite effect in treating PIF. The mechanism may be through inhibiting the activity of NF-kB, decreasing TGF-beta mRNA expression and protein, so as to ameliorate the inflammation and fibrosis.

Animals↗

PubMed2000

[Study of prevention and treatment on acute radioactive injury with huoxue yiqi yangyin recipe].

OBJECTIVE: To reduce the acute toxic and side-effect of radiotherapy with Huoxue Yiqi Yangyin recipe (HYYR). METHODS: Seventy-two nasopharyngeal carcinoma patients that using radiotherapy were divided into two groups: HYYR group (A) and the control group (B) using Wisk lotion for gargling or apply at the skin lesion. RESULTS: The injury on mucous membrane of mouth cavity and skin were 47.2%, 91.7%, 13.9%, 33.3% in group A and B respectively, the degree of injury was different (P < 0.01). The acute reaction of the mucous membrane of mouth cavity did not occur until the cumulative radiation were 41.4 +/- 9.4, 30.9 +/- 8.9 in group A and B respectively, there was significant difference between the two groups (P < 0.01). CONCLUSION: HYYR can reduce the acute radioactive reaction of the skin and mucous membrane of mouth cavity and inhibition of bone marrow.

Aged↗

PubMed2000

[The regulation of calcium in the movement of colonic smooth muscle in wrap restraint stress rats].

OBJECTIVE: To investigate the influence of contraction of isolated colonic smooth muscle and role of guanylin in colonic movement in wrap restraint stress rats. METHODS: By using wrap restraint stress induced defecation rats, the tone of isolated longitudinal and circular colonic muscle strips and guanylin contents in colon and blood were measured by transducer and radioligand binding assay respectively. RESULTS: There were similarities between the intestinal effects of wrap restraint stress in rats and irritable bowel syndrome (IBS) in human. Therefore, wrap restraint stress rat is an appropriate animal model to study stress related intestinal dysfunction. In wrap restraint stress rats, both the tone of smooth muscle and the reaction to K(+), Ca(2+) and acetycholine increased significantly; meanwhile guanylin contents in blood and colon increased also. Trimebutine can decrease the basic tone of smooth muscle and reaction to Ca(2+), K(+) and acetycholine. CONCLUSIONS: The abnormality of colonic smooth muscle contraction is one of the mechanisms in IBS and regulation of colonic smooth muscle contraction is a new method to treat IBS.

Acetylcholine↗

PubMed2000

[Artery denuded model and effects of three kinds of antisense c-myc RNA].

OBJECTIVE: To investigate the effects of antisense c-myc on injured vascular wall. METHODS: Three recombinant retroviral expression vectors, aM1, aM2 and aM3, which loading the reverse fragment of exon1, 2 and 3 respectively, were transferred into denuded rabbit femoral artery wall and were assayed 21 days after operation. RESULTS: (1) The regions of rabbit femoral artery were not only convenient for injury control, drug giving and material drawing, but also gave a neointimal area to media area vatio of 1.37:1. Their intensity and area of c-myc expression in media increased to 1.8 and 1.5 fold of normal value. (2) c-myc expression in aM2, aM3 and aM1 was reduced by 37.5%, 20.8%, and 17.8% with media intensity, 71.5%, 57.2%, and 61.6% with media area and 31.3%, 20.8%, and 17.8% with neointimal intensity respectively. (3) Neointimal area/media area of aM2 group reduced by 72.6%, aM3 group reduced by 35.2%, aM1 group had no significant difference comparing with control group. (4) Proliferating cellular nuclear antigen (PCNA) in the intimal and media of the three antisense transferred groups was enhanced with their expressive intensities, but reduced with expressive areas significantly. (5) With the declining of neointimal area/media area, alpha-SM actin expression in the intimal and media of the three antisense transferred groups was significantly increased (aM2 > aM3 > aM1). CONCLUSION: (1) Rabbit femoral artery denuded model is a satisfactory animal model. (2) Antisense c-myc transferring can reduce or resist the c-myc increase in injured artery wall, resist neointimal hyperplasia and smooth muscle cells dedifferentiation,especially c-myc exon 2 antisense RNA vector aM2.

Actins↗

PubMed2000

[Screening for 6-pyruvoyl-tetrahydrobiopterin synthase (PTPS) deficiency: clinical analysis of 9 patients with PTPS deficiency].

OBJECTIVE: To show the incidence of 6-Pyruvoyl-tetrahydrobiopterin synthase (PTPS) deficiency among hyperphenylalaninemia and conclude the clinical outcome of patients with PTPS deficiency. METHODS: The urinary neopterin (N) and biopterin (B) were determined by HPLC in 69 PKU cases. BH(4) loading test and mutation analysis of PTPS were performed in patients who had abnormal urinary pterin patterns. Three patients with PTPS deficiency were placed on treatment with combined synthetic BH(4) and neurotransmitter precursors such as Dopa and 5-hydroxytryptophan. RESULTS: 9 out of 69 patients, whose urinary N/B exceed 38 [normal: 1.17 (1.4)] and B% were less than 5% [normal: 55.9 (18.6)], were diagnosed as having PTPS deficiency. Four kinds of PTPS gene mutations (P87S, N52S, D96N and G144R) were detected from 4 out of 9 cases with PTPS deficiency. The last mutation was a new mutation. The three typical PTPS-deficient patients had satisfactory physical development, their intelligence quotient (IQ) were 70 approximately 80 after treatment and one partial PTPSD had normal growth and mental development. CONCLUSION: The screening for BH(4) deficiency should be carried out among all patients with hyperphenylalaninemia in order to avoid misdiagnosis.

Biopterins↗

PubMed2000

[Color Doppler ultrasound and quantitative histologic study of angiogenesis in ovarian tumors].

OBJECTIVE: To investigate whether there is any correlation between minimum resistance index (RImin) and microvessel density (MVD) in ovarian tumors. METHODS: The intratumor artery RImin of 61 patients with ovarian tumor was measured by color doppler ultra-sound (CDU) preoperatively. MVD identified by von Willebrand factor was evaluated postoperatively. The relationship between RImin and MVD was analyzed. RESULTS: Compared with the RImin of benign ovarian tumors, the RImin in ovarian cancers was significantly lower (P < 0.001). MVD of ovarian cancer was significantly higher than that of benign tumor both at a 100 magnification (P < 0.01) and a 400 magnification (P < 0.03). There was a significant negative correlation between RImin and MVD at a 100 magnification in benign group (r = -0.67, P < 0.01), in malignant group (r = -0.91, P < 0.01), and in both of groups (r = -0.84, P < 0.01). CONCLUSION: Low RImin reflects high MVD in ovarian tumor.

Female↗

PubMed2000

[The expression of transforming growth factor-alpha and epidermal growth factor receptor in human fetal ovary].

OBJECTIVE: To investigate the expression of transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) in cultured and uncultured human fetal ovary. METHODS: The ovarian tissues were obtained from 20 human female fetuses from 16 to 40 weeks of gestational age and were cultured for 3-9 days. Expression of TGF-alpha and EGFR protein in the fetal ovarian tissues was examined by immunohistochemical technique. RESULTS: TGF-alpha and EGFR were expressed in the oocytes of 17 fetal ovaries, in part of follicular cells and stromal cells. There was no correlation between gestational age and TGF-alpha, EGFR expression (P > 0.05). The immunostaining intensity of oocytes in the cultured fetal ovary was weaker than those of the uncultured ones (P < 0.05). CONCLUSION: TGF-alpha and EGFR may play a role as intraovarian regulators through autocrine and paracrine mechanism.

Cells, Cultured↗

PubMed2000

[Distribution of calcitonin gene-related peptide-like immunoreactive fibres in the temporomandibular joint of rat].

OBJECTIVE: To observe the distribution of calcitonin gene-related peptide-like immunoreactive (CGRP-LI) nerve fibres in rat's temporomandibular joint (TMJ). METHODS: The avidin-biotin-peroxidase complex method and image analysis were employed to detect CGRP-LI nerve fibres in frozen sections of TMJs in eight rats. RESULTS: CGRP-LI nerve fibres were plentifully distributed in TMJs except the central disc band and bone, mainly in the periphery of blood vessels, especially arteries. Density: anterior disc attachment and capsule, (454.6 +/- 72.8) mm(2); posterior portion, (302.7 +/- 43.4) mm(2); lateral portion, (240.2 +/- 23.6) mm(2); medial portion, (229.6 +/- 25.0)mm(2); and peripheral portion of disc, (202.4 +/- 35.2) mm(2). CONCLUSION: CGRP-LI nerve fibres were widely distributed in rat TMJ and were a part of trigeminal sensory nerve. Density was highest in anterior disc attachment and capsule.

Animals↗

PubMed2000

[Endoluminal stent-graft repair of aortic aneurysms].

OBJECTIVE: To study the clinical value of the treatment of aortic aneurysms with endovascular stent-graft prosthesis. METHODS: After a unilateral surgical arteriotomy, Talent, Vanguard and Chinese stent-graft were advanced through the femoral arteries and placed in the proper position of the aneurysm sac under X-ray fluoroscopic guidance. RESULTS: Four patients with descending aneurysm, 1 patient with abdominal aortic aneurysm (AAA) involving the renal artery, superior mesenteric artery and celiac artery, and 1 patient with right common iliac artery aneurysm received straight stent-grafts. Five patients with infrarenal AAA received bifurcated stent-grafts. CT and MRA were performed during a follow-up of 3 - 19 months. Aortic aneurysms were completely excluded from the circulation. Five patients prolonged fever was noted and 1 patient was found to have a leakage 3 months later, and hemiplegia in 1 after procedure. CONCLUSIONS: Endovascular treatment of aortic aneurysm is technically feasible and can effectively exclude aortic aneurysms from the circulation. Endoluminal repair may serve as an interventional strategy to treat aneurysm, especially in patients at high surgical risk, but long term effect needs further study.

Adult↗

PubMed2000

[Intraperitoneal lymphatic chemotherapy for colonic cancer].

OBJECTIVES: To evaluate the effect of intraperitoneal lymphatic chemotherapy with carboplatin and sandostatin on colonic carcinoma and abdominal lymphatic metastasis in patients after radical resection. METHODS: Patients with colonic cancer were divided into two group: abdominal lymphatic chemotherapy group and control group. The lymphatic chemotherapy group was treated at the introduction stage of anesthesia with carboplatin (200 mg) injected intraperitoneally and sandostatin (0.1 mg x 2) injected subcutaneously, whereas the control group was just treated with carboplatin (200 mg) injected intraperitoneally. The platinum levels in abdominal lymphatic nodes were monitored during operation. The two groups were uninterruptedly given intraperitoneal lymphatic chemotherapy or intraperitoneal chemotherapy. Retroperitoneal lymphatic metastasis was evaluated in each patient by abdominal CT scan after operation. RESULTS: The platinum levels in abdominal lymphatic nodes increased more significantly at 2, 3 hours in the lymphatic chemotherapy group than in the control group (P < 0.01). There was no difference in the platinum levels of the portal vein between the two groups, and also no difference in the platinum levels between the lymphatic nodes with or without metastasis. The rates of retroperitoneal lymphatic metastasis after resection were significantly lower in the lymphatic chemotherapy group control group (P < 0.01). CONCLUSION: Intraperitoneal administration of carboplatin combined with sandostatin may elevate the platinum levels in the abdominal lymphatic nodes and reduce the abdominal lymphatic metastasis after radical resection of colonic cancer. It is an effective method for intraperitoneal lymphatic chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2000

[Hyperpolarized cardiac arrest with ATP-sensitive potassium channel opener on myocardial protection during CPB].

OBJECTIVE: To investigate the myocardial protective effects of pinacidil-induced hyperpolarized arrest and compare them with those induced with depolarized hyperkalemic arrest. METHODS: 18 dogs were equally divided into three groups. In the hypothermic hyperpolarization group (LH group), after aortic cross-clamping, a single dose of 4 degrees C pinacidil containing St. Thomas cardioplegic was infused through the aortic root. Temperature during CPB was kept between 26 - 28 degrees C and warmed to 37 degrees C before aortic declamping. Global ischemia lasted 60 min and then reperfusion started for 30 min. In the normothermic hyperpolarized group (WH group), the same procedure was set as in the LH group, except maintaining temperature of 35 - 37 degrees C for CPB and pinacidil solution. In the control group (group C), no pinacidil in St. Thomas solution was the only difference to the other 2 groups. Cardiac arrest and its recovery, the ultrastructure of the myocardium and hemodynamic during ischemia and after reperfusion were observed in the 3 groups. RESULTS: (1) The percentages of normal mitochondria and glycogen were not changed significantly during ischemia and after reperfusion in the LH group, but declined markedly in the group C at ischemic 30, 60 min, and reperfusion for 20 min (P < 0.01). In the WH group, they were lower than those of the group LH, but higher than those of the group C before ischemia. (2) The recoveries of CO, SV, CI, LVSW, RVSW, MAP in the LH group were significantly better than those in the other two groups after reperfusion for 15 minutes and 30 minutes (P < 0.05 or 0.01). However, they were much better in the WH group than in the group C (P < 0.05 or 0.01). (3) The time from cardioplegic infusion to cardiac arrest was shorter in the group C and the group LH than in the group WH. CONCLUSIONS: Myocardial protection for global ischemia during CPB could be well achieved with hyperpolarized cardiac arrest induced by ATP-sensitive potassium channel opener, pinacidil, especially in the hypothermic state. The protection is weaker in normothermia but is still stronger than that with traditional depolarized arrest.

Adenosine Triphosphate↗

PubMed2000

[Optical coherence tomography applied for measurement of nerve fiber layer thickness in normal eyes].

OBJECTIVE: To evaluate the efficiency of optical coherence tomography (OCT) on quantifying retinal nerve fiber layer (RNFL) thickness and its reproducibility and investigate the difference of RNFL thickness between different groups. METHODS: According to their age, 152 eyes of 152 normal subjects were classified into six groups (such as 10 year, 20 year group, etc.), and investigated by OCT to measure the RNFL thickness. Each subject had circular scans around the optic nerve with a circle size of 3.46 mm. The RNFL thickness in different groups was analyzed. Intraclass correlation coefficient (ICC) in fifty eyes of 37 subjects was calculated. RESULTS: The mean RNFL thickness of 152 eyes was (90.09 +/- 10.81) microm, (140.27 +/- 10.60) microm, (85.03 +/- 14.01) microm, (140.27 +/- 9.70) microm and (114.11 +/- 6.08) microm (temporal, superior, nasal, inferior and the mean of the whole layer, respectively). Least significant difference (LSD)-t test was applied for multiple thickness comparisons of the mean and different quadrants among different groups. The results showed there were significant differences between the 60 year group and others except the 50 year group in temporal, superior, inferior quadrants and mean RNFL thickness (P = 0.000 - 0.019), and between each of 10 to 40 year groups and each of 50 to 60 year groups in the mean RFNL thickness (P = 0.000 - 0.026). ICCs of RNFL thickness measured by OCT were 0.78, 0.66, 0.64, 0.52 and 0.74 (temporal, superior, nasal, inferior and mean, respectively). CONCLUSIONS: Normal RNFL thickness can be measured accurately by OCT. There are some differences of RNFL thickness between different groups in normal persons.

Adolescent↗

PubMed2000

[Qualitative and quantitative measurement of retinal nerve fiber layer in primary open angle glaucoma by optical coherence tomography].

OBJECTIVE: To study the characteristics of optical coherence tomography (OCT) of primary open angle glaucoma (POAG), the difference of retinal nerve fiber layer (RNFL) thickness between normal persons and patients with POAG and the correlation between RNLF and visual field index. METHODS: Eighty-three cases (149 eyes) with POAG and 83 normal persons (150 eyes) were tested by OCT with circular scans around the optic nerve head (diameter = 3.46 mm) to observe the features of OCT. Statistic analysis was taken to compare the difference of RNFL thickness in quadrants and means between normal and glaucomatous group, and the difference of the thickness among the stages in POAG. Linear correlation and regression analysis was used to show the correlation between RNFL thickness and visual field index of 115 eyes of glaucomatous patients. RESULTS: The RNFL thickness measured by OCT in normal subjects is the thickest in superior and inferior quadrants, less in thickness in temporal and the thinnest in nasal quadrant. The curve showed double peaks. The RNFL of glaucomatous patients showed local thinness or defect, diffuse thinness or combination of the above two types. The mean RNFL thickness of normal group was (90.1 +/- 10.8) microm, (140.4 +/- 10.5) microm, (85.2 +/- 14.0) microm, (140.4 +/- 9.7) microm and (114.2 +/- 6.0) microm, of glaucomatous group was (56.0 +/- 31.0) microm, (81.0 +/- 36.3) microm, (47.1 +/- 27.5) microm, (73.4 +/- 38.4) microm and (64.6 +/- 28.8) microm in temporal, superior, nasal, inferior quadrant and the whole area, respectively. There is significant difference of RNFL thickness between the normal and glaucomatous group (P < 0.000), and there are significant differences among the three stages (early, developing and late) of glaucomatous group (P < 0.000). There is a close negative relationship between RNFL thickness and visual field index (r = -0.796, P < 0.0001). The sensitivity and specificity of RNFL thickness measured by OCT were 93.3% and 92.0%, respectively. CONCLUSION: OCT can quantitatively measure the RNFL thickness and show the difference of RNFL between normal persons and glaucomatous patients. The RNFL thickness gradually decreases while visual field defect increases with the development of POAG.

Adolescent↗

PubMed2000

[Reducing incidence and mortality from rectal cancer by polypectomy: a prospective cohort study].

OBJECTIVE: To address the hypothesis that colorectal cancers often arise from precursor lesion(s), either adenomas or non-adenomatous polyps. METHODS: A population-based mass screening for rectal cancer using 15cm rigid endoscopy was conducted in Haining County, Zhejiang province, from 1977 to 1980. Of over 230,000 participants, 4,076 of them were diagnosed with precursor lesions, either adenomas or non-adenomatous polyps, which were then removed. All individuals with precursor lesions were followed and re-examined by endoscopy every two to five years through 1998. RESULTS: After the initial screening, 952 metachronous adenomas and 417 non-adenomatous polyps were detected and removed from the cohort. Furthermore, 27 cases of colorectal cancer were detected and treated. Log-rank tests showed that the years of survival significantly increased among those cancer patients who had undergone mass screening compared to other rectal cancer patients (P < 0.001). According to the population-based cancer registry in Haining County, both age-adjusted incidence and mortality rates from rectal cancer decreased from 1977 to 1996. Observed accumulative incidence and mortality rates decreased to 68.6% and 82.4% comparing with expected numbers during the last 20 years. CONCLUSION: Mass rectal cancer screening in the general population followed by routine endoscopy for high-risk patients could decrease both rectal cancer incidence and mortality rates.

Adenoma↗