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Biomedical subjects

X Zhu

Publications and source records attributed to X Zhu.

At least 361 records · Page 20Linked to original sources
PubMed1999

Ultrasound biomicroscopic study on changes of ocular anterior segment structure after topical application of cycloplegia.

OBJECTIVES: To observe the changes of the ocular anterior segment structure and the relationship between the intraocular pressure (IOP) and these changes after the topical application of cycloplegia using ultrasound biomicroscope (UBM), especially to observe the changes of ciliary body thickness, ciliary process thickness and ciliary process-lens distance. METHODS: The quantitative measurement with UBM and the measurement of IOP were performed before and after the topical application of 2% homatropine solution in 48 normal eyes. The results were statistically analyzed. RESULTS: In the parameters showing the changes of the anterior chamber angle after topical use of 2% homatropine solution, both the trabecular iris angle and the angle opening distance 250 decreased. The iris thickness 1 increased. The anterior chamber became deeper and the iris-lens contact distance became shorter. All these differences were statistically significant (P < 0.05). In the parameters showing the changes of ciliary body, the ciliary body thickness and the ciliary process thickness decreased. The scleral ciliary body angle increased. The iris-zonule distance decreased and the ciliary process-lens distance increased. All these differences were statistically significant (P < 0.05). The IOP increased from 17.63 +/- 3.45 mm Hg to 18.23 +/- 3.53 mm Hg after topical use of 2% homatropine solution, but the difference was not statistically significant (P > 0.05). CONCLUSIONS: After the topical use of cycloplegia, the anterior chamber becomes deeper. The anterior chamber angle becomes narrower, and the ciliary body becomes thinner and moves backward and the ciliary process-lens distance increases. By using UBM the structures of the ocular anterior segment in the living state can be observed and measured quantitatively. The ultrasound biomicroscopic imaging has its advantages in the morphological study of the ocular anterior segment.

Adult↗
PubMed1999

Angiotensin I-converting enzyme gene polymorphism in Chinese patients with obstructive sleep apnea syndrome.

OBJECTIVE: To investigate the relationship of an insertion/deletion (I/D) polymorphism of the angiotension-converting enzyme (ACE) gene to obstructive sleep apnea syndrome (OSAS) patients and the control subjects. METHODS: Genomic DNA was extracted from blood samples and amplified by polymerase chain reaction (PCR). PCR primers flanked the polymorphic region in intro 16 of the ACE gene. RESULTS: OSAS patients had significantly higher frequencies of I/I genotype and insertion allele of the ACE gene as compared with the control subjects in Chinese population. The OSAS patients with I/I genotype had significantly longer apnea time, lower minimum SaO2 and greater AHI than the OSAS patients with I/D genotype. CONCLUSION: These results indicate that the I/I genotype and I allele are a risk factor for OSAS in Chinese.

Adult↗
PubMed1999

Diagnostic role of antibodies to glutamic acid decarboxylase in latent autoimmune diabetes mellitus in adults.

OBJECTIVE: To investigate the diagnostic role of antibodies to glutamic acid decarboxylase (GAD65-Ab) in latent autoimmune diabetes of adults (LADA) and the frequency of GAD-Ab in Chinese patients initially diagnosed as non-insulin-dependent diabetes mellitus (NIDDM). METHODS: Forty-five control subjects and 195 consecutive inpatients initially classified as NIDDM with > or = 35 years of age at onset and nonketotic history for > 6 months after diagnosis, were recruited. In vitro transcripted and translated recombinant human 35S-GAD65 was used in radioligand assay of GAD-Ab. RESULTS: The overall prevalence of GAD65-Ab was 14.8% (29/195) in NIDDM patients and 2.2% (1/45) in control subjects, respectively. Of the 29 GAD65-Ab positive patients, 17 (58.6%) were insulin-deficient while 12 (41.4%) were non-insulin-deficient. The prevalence of GAD65-Ab in NIDDM group with age of < 40 years at diabetes onset, ketotic history, body mass index (BMI) < 21 kg/m2, were significantly higher than that of corresponding control diabetic subgroups (2.5, 4.1 and 3.2 times, respectively). The sex, duration, symptoms of polyphagia, polydipsia, polyuria and weight loss at onset of the disease were not related to the prevalence of GAD65-Ab positivity. CONCLUSIONS: In China, patients initially diagnosed as NIDDM may in many cases suffer from LADA. Testing by GAD65-Ab may be of assistance to identifying LADA at the earliest stage of disease.

Adult↗
PubMed1999

Relationship between angiotensinogen gene M235T variant with diabetic nephropathy in Chinese NIDDM.

OBJECTIVE: To investigate whether angiotensinogen (AGT) gene M235T variant is associated with non-insulin-dependent diabetes mellitus without nephropathy (DN-), and diabetic nephropathy (DN+) in Chinese non-insulin-dependent diabetes mellitus (NIDDM). METHODS: The subjects in DN+ group, DN- group and control group were well matched with sex, age and duration of disease, and the two case groups were divided into two subgroups as with and without hypertension respectively. The M235T polymorphism of AGT gene of 84 cases with DN-, 96 patients with DN+ and 98 controls were determined by polymerase chain reaction (PCR) amplification and restriction fragment length polymorphism (RFLP) analysis of the region of the variant, i.e. M235T polymorphism. RESULTS: The increased frequencies of T allele (0.82) and TT genotype (0.70) were observed in 96 subjects with DN+ as compared with 98 control subjects (0.63 and 0.43, respectively, P = 0.003, P = 0.0004). The odds ratio associated with TT genotype was 3.47 (95% CI: 1.51-7.94; P = 0.0033) for diabetic nephropathy in analysis adjusted for several risk factors of diabetic nephropathy, such as body-mass index, systolic and diastolic blood pressure, serum cholesterol, low density lipoprotein and high density lipoprotein. Subgroup analysis of the 67 patients in DN+ group with hypertension revealed similar distributions of M235T genotypes and alleles to those in the DN+ without hypertension subgroup. There was no difference in allele and genotype distribution between 84 DN- patients and the controls. Similarly, frequencies of the AGT M235T genotype and allele were not different between two DN- subgroups. CONCLUSIONS: AGT gene M235T polymorphism is associated with diabetic nephropathy in NIDDM. TT genotype of the AGT gene might be an independent risk factor of diabetic nephropathy in Chinese NIDDM patients.

Adult↗
PubMed1999

[Induction of potent antitumor immune response of leukemia antigen-pulsed dendritic cells by IL-2 gene modification].

OBJECTIVE: To investigate whether adenovirus-mediated IL-2 gene modification can improve antitumor immunity of the tumor antigen-pulsed dendritic cells(DC) in vivo. METHODS: DC were generated from bone marrow, then, pulsed with FBL-3 erythroleukemia cell lysates and transfected with IL-2 gene simultaneously. IL-2 secretion and T cell stimulating activity of the DC were detected. The number and cell subsets of draining lymph nodes, cytotoxic lymphocyte(CTL) activity, and the increase of protective effect for the mice s.c. vaccinated with DC were observed. RESULTS: IL-2 gene-modified, antigen-pulsed DC could secrete high level of IL-2 in vitro, stimulate proliferation of syngeneic T cells markedly. DC vaccine could increase the number of draining lymph node and induce CTL activity, which directed to FBL-3, more significantly. After the DC vaccination, the survival time of the mice challenged with wild-type FBL-3 cells were prolonged. CONCLUSION: Antitumor immune response could be induced more potently by vaccination with IL-2 gene modified, antigen-pulsed DC.

Animals↗
PubMed1999

[Design and synthesis of anti-PML-RAR alpha antisense and its effects on the growth and apoptosis of NB4 cells].

OBJECTIVE: To synthesize antisense oligodeoxynucleotides (AS) targeting the fusion point region (FUAS) and the start codon region (STAS) of the long type PML-RAR alpha mRNA and investigate its stability, specificity and effects on the growth and apoptosis of NB4 cells. METHODS: NB4 cell apoptosis was assayed by flow cytometry, cell-fluorescence and DNA gel electrophoresis. Trypan blue exclusion was used for cell counts, and polyacrylamide gel electrophoresis for oligodeoxynucleotides. RESULTS: The synthesized 18 bp phosphorothioate oligodeoxynucleotides was stable, resistant to nuclease, and no unspecific effects. Both STAS and FUAS could inhibit the NB4 cell growth in a dose-dependent manner. Low concentration (20 micrograms/ml) of STAS or FUAS resulted in growth inhibition of 0%-11.3%, and the highest inhibition was found at concentration of 80 micrograms/ml (inhibition rate 50.0%-67.7%). Cell DNA content analyzed by flow cytometry showed the typical profile of apoptotic cells at 7th day, 9th day of treatment with FUAS. Percentages of apoptotic cells in FUAS-treated cells was 9.3%, 24.5%, 41.0% and 34.2% after 3, 5, 7 and 9 days of FUAS treatment, respectively. CONCLUSION: STAS and FUAS successfully synthesized and both of them could inhibit the growth and induce the cell apoptosis of NB4 cells.

Apoptosis↗
PubMed1999

[Effects of anti-PML-RAR alpha antisense on cell morphology and expression of PML-RAR alpha mRNA and protein of NB4 cells].

OBJECTIVE: To investigate the effects of anti-PML-RAR alpha antisense (FUAS) on cell morphology, expression of PML-RAR alpha mRNA and PML-RAR alpha/PML protein localization of NB4 cells. METHODS: PML-RAR alpha mRNA expression was assayed by RT-PCR and PML-RAR alpha/PML protein localization by immuno-fluorescence. RESULTS: NB4 cells were partially differentiated after 5 days of FUAS treatment and typical apoptosis was found after 7 days incubation with FUAS. The expression of PML-RAR alpha mRNA at 24 h was already down regulated in FUAS-treated cells. After 24 h, 72 h and 120 h incubation with FUAS, PML-RAR alpha mRNA showed 52.0%, 68.7% and 23.4% reductions, respectively, as compared with that of control. Immuno-fluorescence analysis with anti-PML monoclonal antibody showed disappearance of microgranules, residual granules becoming larger discrete dots at 24 h of FUAS treatment and almost disappearence of dots at 120 h. CONCLUSION: FUAS specifically blocks the expression and translation of PML-RAR alpha gene, makes the production of PML-RAR alpha fusion protein decrease or disappear and prompts cell differentiation.

Cell Division↗
PubMed1999

[Infiltration of monocytes/macrophages and expression of monocyte chemoattractant protein-1 in gingival tissues from patients with rapidly progressive periodontitis].

OBJECTIVE: To find if there was any difference in monocytes/macrophages infiltration and monocyte chemoattractant protein-1(MCP-1) expression between rapidly progressive periodontitis (RPP) and adult periodontitis (AP) tissues. METHODS: Inflamed gingival specimens (20) were obtained from RPP(14) and AP(6) patients, and specimens from clinically healthy subjects (H,6) as control. The monocytes/macrophages and MCP-1 expression were detected by immuno-histochemistry SP assay with antibodies against CD14 and CD68, and rabbit anti-MCP-1 antibody. RESULTS: There were no differences in the mean counts (+/- SD) of monocytes/macrophages and MCP-1 positive cells between RPP and AP groups. CONCLUSION: Though rapid and severe periodontal destruction occurs in RPP, there is no differences in monocytes/macrophages infiltration and MCP-1 expression in gingival tissues between rapidly progressive periodontitis and adult periodontitis patients.

Adult↗
PubMed1999

[Extensive HLA class II studies in Chinese narcoleptic patients].

OBJECTIVE: Narcolepsy is a debilitating, lifelong sleep disorder. Its familial occurrence suggests that genetic factors may be of importance in the etiology. Narcolepsy is a very rare disease among Chinese, thus it was of interest to study the association of narcolepsy with the HLA system in Chinese narcoleptic patients. METHODS: To explore the role of HLA-DRB genes in the development of narcolepsy, we studied 10 narcoleptic patients and 50 race matched controls in whom HLA-DR typing was performed by the method of DNA amplification with sequence-specific primers (PCR-SSP). RESULTS: All narcoleptic patients were found to be of DRB1 * 1501 and DRB5 * 0101 genotype. CONCLUSION: These results indicate that HLA-DRB1 * 1501 is a better primary candidate susceptibility gene for narcolepsy in Chinese.

Adult↗
PubMed1999

[Function research of esophageal lower sphincter in infant with hiatal hernia].

OBJECTIVE: To investigate the relationship between gastroesophageal dynamics of infantile hiatal hernia (HH) and gastroesophageal reflux (GER) and to assess the curative effects of antireflux surgery. METHODS: Ambulatory 24-hr esophageal pH-metry and esophageal manometry were studied in 26 patients with HH before and after surgery. RESULTS: By radiology, patients were divided into group of sliding HH (n = 16, group I) and group of para-esophageal or combined HH (n = 10, group II). All patients showed GER. The duration of the longest episode, and the percentage of the time at pH < 4 were significantly greater in lying position than those in upright position (P < 0.05). All parameters were significantly decreased after operation (P < 0.01). Lower esophageal sphincter length (LESL) increased significantly postoperatively. In group I, lower esophageal sphincter pressure (LESP) and barrier pressure (BP) was increased after surgery, but no significant difference was seen in LESP and BP in group II. Intragastric pressure (GP) significantly reduced after operation. GP in group II before operation was higher than that in group I (P < 0.05). A second high pressure zone in the esophagus was found in 67% of patients in group I and 14% patients in group II. CONCLUSIONS: Most patients with infantile HH and GER decreased LESL, LESP and increased GP. Differential gastroesophageal dynamics is associated with types of hiatal hernia. It is very important to remain enough LESL in mechanism of Dor antireflux surgery. To prevent respiratory infection is an important measure to prevent patients from relapse after surgery.

Child, Preschool↗
PubMed1999

[The level of expression of adhesion molecules CD44v6 and E-cadherin in colorectal cancer and analysis of correlates with metastasis].

OBJECTIVE: To determine the expression of adhesion molecules CD44v6 and E cadherin in colorectal cancer and its relation with metastasis. METHODS: The expression of CD44v6 and E-cadherin in 32 patients with colorectal carcinoma was investigated using immunohistochemical staining, which was performed on surgical specimens. RESULTS: No significant correlation with CD44v6 and histologic type, TNM and Dukes staging was noted, but it was significantly correlated with lymph node and hematogenous metastasis. E-cadherin was strongly expressed in normal epithelium examined. However, E-cadherin expression in colorectal carcinoma was reduced (positive rate 46.9%). Metastatic colorectal carcinoma showed significant reduction (positive rate 20%). CONCLUSION: CD44v6, E-cadherin immunoreactivity are significantly correlated with lymph node and hematogenous metastasis.

Cadherins↗
PubMed1999

[Preoperative arterial infusion chemotherapy of colorectal carcinoma pathological and clinical effects].

OBJECTIVE: To investigate the pathological and clinical effects of preoperative selective intra-arterial infusion chemotherapy on colorectal carcinoma. METHODS: 30 patients with colorectal carcinoma underwent selective regional arterial angiography by Seldinger's method followed by intra-arterial infusion chemotherapy. RESULTS: changes of karyopyknosis, karyorrhexis, coagulation and necrosis of cytoplasm in cancer cells around vascular vessels were found in all cases. Interstitial edema, invasion of inflammatory cells, fibroelastosis around cancer cells, proliferous intima, thrombus and inflammation of vessels were also found at the same sites. CONCLUSIONS: Histological changes are significant after preoperative selective intra-arterial infusion chemotherapy for colorectal carcinoma. This therapy can relieve symptoms.

Adult↗
PubMed1999

[Early results of 1,110 cases of coronary artery bypass].

OBJECTIVE: To introduce our experience with Coronary artery bypass. METHODS: From January 1996 to March 1999, coronary artery bypass was in 1110 patients at our hospital. They were 985 men and 125 women, aged 27 - 78 years (57 +/- 9). 500 patients were aged over 60 years. 670 patients had a history of myocardial infarction. 450 patients suffered from instable, and 460 from stable angina. 169 patients had stenosis of the left main trunk (>or= 50%). The heart function of 240 patients was over NYHA class III, the EF of 123 patients was less than 40%. 454 patients were associated with hypertension, 133 with diabetes, 131 with ventricular aneurysm, 48 with valvular disease, and 5 with rupture of ventricular septal. 1048 procedures were performed on hypothermia cardiopulmonary bypass (CPB) and 60 on beating heart. Myocardial preservation was carried out by cold blood cardioplegia with potassium. The average time of CPB was 115 +/- 35 minutes, and that of aortic cross clamp was 72 +/- 24 minutes 110 cases received one graft, 145 cases two grafts, 415 cases three grafts, and 439 cases four and more than four grafts. Left internal mammary artery, great saphenous vein, and radial artery were used as coronary artery bypass conduits on 751, 877 and 101 patients, respectively. Total arterial myocardial revascularization was performed on 72 patients. Concomitant operation included ventricular aneurysmetomy (112 cases), plication (14), left ventriculoplasty (5), valvular procedures (48), repair ventricular septal rupture (5). RESULTS: 1 101 patients were discharged uneventfully. Early death occurred in 9 patients, (0.81%). Complication included low cardiac output (11 cases), introaortic balloon pump (7), perioperative myocardial infarction (2), complication of brain (3), and rethoractomy for bleeding (4). CONCLUSIONS: To identify adequate target vessel and completely revascularize ischemic myocardium are the key of coronary artery bypass. Perioperative treatment is important.

Adult↗
PubMed1999

[Pathological changes following retrograde infusion of methyl violet in the parotid gland of the miniature pig].

OBJECTIVE: To investigate the pathologic changes induced by infusion of 1% methyl violet in the parotid gland of the miniature pig (minipig). METHODS: Methyl violet (either 0.6 ml, 1.0 ml, or 4.0 ml) was injected into parotid glands of fifteen minipigs. The parotid glands were harvested for gross and histopathologic study after 1 week, 2 weeks, 1 month, 3 months and 6 months. RESULTS: The pathological changes induced by retrograde injection of methyl violet included necrosis or atrophy of acinar cells and fibrosis of the gland. The ductal system underwent atrophic changes, and thrombotic obliteration of main duct. CONCLUSION: Retrograde infusion of 1% methyl violet results in complete atrophy and fibrosis of the parotid gland in the minipig.

Animals↗
PubMed1999

[The application of chopping method for phacoemulsification of hard nucleus cataract].

OBJECTIVE: The study was designed to investigate the application of chopping method for phacoemulsification of hard nucleus cataract. METHODS: Modified stop and chop technique was used to emulsify the hard nucleus cataract. The degree of nuclear hardness in 80 eyes was grade IV. RESULTS: Postoperatively, the visual acuity with correction was >or= 0.9 in 76.25% at 3 months. There were mild corneal edema in 8 cases, moderate corneal edema in 2 cases and posterior capsular rupture in 1 case. CONCLUSION: The modified stop and chop technique enables the tenacious nuclear plate to rupture easily, thus the stress on the zonules and capsule can be decreased, and in the mean time the technique needs less phaco energy and time.

Aged↗