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Geng Xu

Publications and source records attributed to Geng Xu.

At least 37 records · Page 2Linked to original sources
PubMed2004

[Association of angiotensinogen gene M235T variant with hypertrophic cardiomyopathy].

OBJECTIVE: To evaluate the influence of the angiotensinogen(AGT) gene M235T variant on the prevalence and severity of hypertrophic cardiomyopathy(HCM). METHODS: The authors conducted a case-control study on 152 subjects, including 72 HCM patients and 80 normal controls. Polymerase chain reaction(PCR) combined with restriction fragment length polymorphism(RFLP) was used to detect the M235T variant of AGT gene. Interventricular septum thickness, left ventricular posterior wall thickness and apical wall thickness were measured by means of M-mode echocardiography under two-dimensional guidance in the parasternal long-axis plane and apical two- and four-chamber views. RESULTS: (1) The genotype distributions of AGT gene in both groups were in agreement with Hardy-Weinberg equilibrium. (2) The genotype distributions of the M235T variant differed significantly in HCM patients and controls(chi-square=6.090 P<0.05). The frequencies of TT genotype and T235 allele in HCM patients were higher than did the patients in controls(TT genotype 0.63 vs 0.45 OR=2.037 95%CI 1.064-7.899 P<0.05 T235 allele 0.78 vs 0.64 OR=1.990 95%CI 1.197-3.308 P<0.01). (3)The patients with the TT genotype had significantly greater mean left ventricular maximal wall thickness than did the patients with the MM and MT genotypes [(19.1+/-4.8) mm vs(15.3+/-2.6)mm and(16.2+/-5.1)mm F=4.261 P<0.05]. CONCLUSION: The variant M235T of the AGT gene is significantly associated with HCM in this population. The genotype TT or allele T might be a genetic risk factor for the development and extent of hypertrophy in HCM patients.

Adult↗
PubMed2004

[Transnasal endoscopic frontal surgery for chronic frontal sinusitis].

OBJECTIVE: The recurrence of chronic frontal sinusitis after endoscopic surgery is mainly due to the mismanagement of frontal recess and frontal sinus orifice. The aim of this study is to investigate the characteristics of chronic frontal sinusitis and to advance the clinical therapeutic efficacy. METHODS: Different methods were used to manage different local diseases in frontal sinus orifice or frontal recess in 58 cases (96 sides) with chronic frontal sinusitis by nasal endoscopic surgery. RESULTS: Different degree of middle meatal obstruction was seen in all cases at operation. The situation of frontal sinus ostium and frontal recess was as follows: 38 sides obstructed by swollen mucosa, polypoid mucosa or polyps, no cell obstruction at frontal sinus orifice; 34 cases constricted by over development of agger nasi cells, ethmoid bulla or terminal cell at frontal recess; 15 cases obstructed completely by over development cells at frontal recess; osteal stenosis at frontal sinus orifice in 9 cases. The situation in frontal sinus was as follows: pus accumulation in 18 sides, mucosal swollen in 21 sides, mucosal congestion in 49 sides, no obvious mucosal diseases in 8 cases. Follow-up for 6-20 months showed that 69 sides (71.9%) were cured, 17 sides (17.7%) better and 10 cases (10.4%) recurrent. CONCLUSION: Obstruction of osteomeatal complex and frontal recess is the main causes of chronic sinusitis. There are four pathologic states in obstruction of frontal recess and frontal ostium. Different operative methods should be taken according to different pathological changes. The operative effects is still needed to improve.

Adult↗
PubMed2004

[The T-lymphocytes subsets expression in the human recurrent nasal polyps].

OBJECTIVE: To investigate the expression of T-lymphocyte subsets (CD4+, CD8+ and CD45RO+ cells) in human recurrent nasal polyps. METHOD: Nasal polyps tissue samples and peripheral blood were obtained from 17 patients, normal human inferior turbinate mucosa and peripheral blood were obtained as well. Flow cytometry was adopted to detect the expression of surface markers of the T-lymphocytes. All data were analyzed with t-test. RESULT: There were significantly large number of CD4+, and CD45RO+ cells in the tissue of recurrent nasal polyps. The expression percentage of CD3+ CD4+ cells was significantly higher than that of CD3+ CD8+ cells. Ratio of CD3+ CD4+/CD3+ CD8+ was 1.956 +/- 0.093. CONCLUSION: There were generous of T-lymphocytes expression in human recurrent nasal polyps. The ratio of the T-lymphocytes subsets was abnormal high than the usual and this indicated the immunological function were in disorder in the local area. The abnormally higher expression of CD3+ CD4+ cells in the local area may play an important role in the recurrence of human nasal polyps.

Adolescent↗
PubMed2004

[Computer-assisted anatomical study of nasofrontal region].

OBJECTIVE: To evaluate the value of Advantage Windows 3.1 (AW 3.1) software for anatomical study of nasofrontal region, and to study the CT characteristics of nasofrontal region which related to the frontal sinus surgery. METHODS: Eighty patients underwent axial consecutive computed tomography scans and these data were studied with AW 3.1 software which provided reconstructional imaging of continuous coronal, sagittal, axial sections. Some related structures of nasofrontal region were studied and measured. RESULTS: AW 3.1 software could identify and measure the following structures accurately: The diameter of frontal sinus was (22.5 +/- 8.6) mm in height, (16.3 +/- 6.8) mm in depth, (23.8 +/- 9.8) mm in breadth. The diameter of frontal sinus ostium: the anterior-posterior diameter was (7.3 +/- 1.7) mm, the transverse diameter was (8.5 +/- 1.9) mm. The width of nasal beak of frontal bone(5.9 +/- 1.4 ) mm. The distance of frontal sinus ostium to the floor of columella nasi and the corresponding angle to the nasal floor were (60.8 +/- 4.2) mm and (70.1 +/- 4.7) degrees. The superior attachment sites of the uncinate process were as follows: lamina papyracea 41%, posteromedial wall of agger nasi cell 11%, middle turbinate 19%, anterior skull base 16%, superior bifurcation 13%. The cells could impinge on the frontal recess to cause obstruction (terminal recess 38.8%, anterior ethmoid cell 27.6%, agger nasi cells 24.5%). The accessory cells could impinge on the frontal sinus (perifrontal cells 32.7%, superaorbital cells 38.8%, intersinus septal cells 32.0%). There was significant difference between two groups of characteristics of nasofrontal region. CONCLUSIONS: AW 3.1 software is a helpful and powerful new tool for anatomical study of nasofrontal region and for preoperative evaluation. The structures of nasofrontal region are complex and various, frontal sinusitis almost always results from the obstruction of frontal sinus outflow tract. These results of anatomical study of nasofrontal region are helpful in directing the functional endoscopic surgery in frontal sinus.

Adult↗
PubMed2004

[Endoscopic thyroid gland surgery without carbon dioxide neck insufflation].

OBJECTIVE: To evaluate endoscopic thyroid gland surgery without carbon dioxide neck insufflation. METHODS: Sixteen patients with thyroid gland benign tumor, aged from 23-62 years, were selected and treated with endoscopic surgery. Eight cases received whole thyroid lobectomy and the other eight cases received partial thyroid lobectomy, the procedure was through a wall method or a single 2.0-3.0 cm horizontal skin incision. Among the 16 cases, 6 were thyroid adenoma and 10 were nodular goiter. RESULTS: All patients received endoscopic surgery, 2 cases with sub-clavicle approach and 14 cases with a single 2.0-3.0 cm horizontal skin incision approach. The recurrent laryngeal nerve and parathyroid glands were easily identified and preserved during operation, the operating time lasted from 1.1 hours to 4.0 hours, no complication occurred, the postoperative cosmetic outcome was excellent. CONCLUSIONS: The results indicated that gasless technique is feasible and safe, so it suggested that the video-assisted thyroid surgery without carbon dioxide neck insufflation could be an alternative for thyroid gland surgery.

Adult↗
PubMed2004

[Diagnosis and treatment on osteoradionecrosis of skull base after radiotherapy for nasopharyngeal carcinoma].

OBJECTIVE: To investigate the diagnosis and management on osteoradionecrosis (ORN) of skull base in the patients with nasopharyngeal carcinoma (NPC) after radiotherapy. METHODS: All patients (n = 15) diagnosed as NPC and ORN of skull base were studied on the clinical data, diagnosis and therapy. RESULTS: All the patients were found with foul odor, headache, bleeding and exposed necrotic bone. 9 patients were treated by surgery, among them 2 patients died of temporal lobe radionecrosis, and the survival time of remaining 7 patients was 2 to 7 years. 5 patients with extensive ORN and 1 patient with local ORN were treated by conservative methods, among them 3 died of nasopharyngeal bleeding and 1 died of respiratory and heart failure, survival time of the remaining 2 patients was 3 to 5 years. CONCLUSIONS: ORN can be diagnosed by clinical characteristics, CT or MR, and endoscopic findings. Surgery is the best choice for ORN. The patients with extensive ORN or radiation-induced cranial neuropathy had poor prognosis. The most common causes of death were nasopharyngeal bleeding and exhaustion.

Adult↗
PubMed2003

Apoptosis induced by simvastatin in rat vascular smooth muscle cell through Ca2+-calpain and caspase-3 dependent pathway.

Several studies have shown that simvastatin induces apoptosis in a variety of cell lines including vascular smooth muscle cells (VSMCs), but the exactly mechanisms involved in it is not very clear. The aim of this study was to investigate the mechanisms and signal pathways involved in apoptosis induced by simvastatin. When exposed to 30 microM simvastatin, [Ca2+]i in VSMCs increased with time and reached to 336 +/- 52 nM at 6 h, more than four-fold of control (P<0.01, n=5). Verapamil (80 microM), a membrane voltage-dependent Ca2+ channel blocker, attenuated simvastatin-induced augmentation of free calcium concentration from 336 +/- 52 nM to 144 +/- 34 nM (P<0.01). After being exposed to 30 microM simvastatin for 8 h, calpain activity markedly increased (P<0.05, n=4) and reached to more than three-fold of control at 12 h (P<0.01). Caspase-3 was also activated by simvastatin after 12 h. Verapamil and PD150606, a cell-permeable selective calpain inhibitor, significantly inhibited simvastatin-induced augmentation of calpain activity and blocked caspase-3 activation, respectively. Furthermore, 80 microM verapamil and 100 microM PD150606 decreased simvastatin-induced apoptosis rate from 24.2 +/- 1.7% to 7.9 +/- 0.6% (P<0.01, n=4) and 9.5 +/- 1.9% (P<0.01), respectively and also prevented simvastatin-induced DNA laddering. In conclusion, we indicated that simvastatin increases cytosolic free calcium concentration mainly through calcium influx from extracellular solution and then induces apoptosis by activating caspase-3 via calcium-dependent protease calpain.

Acrylates↗
PubMed2003

[Effects of ischemic reperfusion on the expression of cell adhesion molecules and monocyte chemotactic protein-1 and the protective role of MgSO4].

OBJECTIVE: To investigate the effect of ischemic reperfusion(I-R) on the expression of P-selectin(Ps) of platelets, CD11b of leukocytes, monocyte chemotactic protein-1(MCP-1) mRNA of myocardial tissue and the protective role of MgSO(4). METHODS: Ischemic reperfusion rat model was established in the experiments. All animals were randomly divided into 3 groups sham group, I-R group and Mg(2+) group. The expression of Ps of platelets and CD11b of leukocytes was determined by flowcytometry and the expression of MCP-1 mRNA of myocardial tissue was measured by RT-PCR admission and at 5, 30, 60, 180, 360 min of reperfusion (R5, R30, R60, R180, R360). RESULTS: The expression of Ps of platelets in I-R group began to rise at R5 and peaked at R60 P<0.01); the expression of CD11b of leukocytes was significantly higher than that of the control groups P<0.01 and P<0.05) the expression of MCP-1 mRNA of myocardial tissue began to rise at R60,reaching the highest at R360 P<0.01) the concentration of Ca(2+) of the serum was significantly higher than that of the control groups P<0.01 and P<0.05). MgSO(4) inhibited the expression of Ps of platelets and MCP-1 mRNA of myocardial tissue and decreased serum Ca(2+)concentration, but did not affect the expression of CD11b of leukocytes. CONCLUSION: I-R can increase the expression of cell adhesion molecules and cell chemotactic factor. MgSO(4) may protect myocardial tissue from ischemic reperfusion injury by inhibiting the expression of Ps of platelets and MCP-1 mRNA of myocardial tissue and decreasing the concentration of Ca(2+) of the serum.

Animals↗
PubMed2003

[Association of coagulation factor V, VII gene polymorphisms with coronary heart disease].

OBJECTIVE: To study the distribution of coagulation factor V(FV), VII(FVII) gene polymorphisms in Chinese Han population and the association of the polymorphisms with coronary heart disease(CHD). METHODS: Genotypes of FV FVII were typed in 234 CHD patients and 210 controls by polymerase chain reaction-restriction fragment length polymorphism. Selected coronary angiography was performed in 234 CHD patients. RESULTS: FVII allelic frequencies of R,Q and H7,H6 were 94.6%, 5.6%, 70.3%, 29.7% and 91.9%, 8.1%, 60.9%, 39.1% in CHD group and control group respectively. Genotype distribution was in accordance with Hardy-Weinberg equilibrium. There was no significant difference in frequencies of allele and genotype in R353Q or HVR4 polymorphisms between CHD group and control group. The distribution of allele and genotype in R353Q was of significant difference between non-myocardial infarction subgroup and myocardial infarction subgroup (chi2 = 4.711, P<0.05, OR=0.37,95% CI: 0.15-0.94). However, HVR4 polymorphism was not found to be of significant difference within two group (chi2 = 0.142, P>0.05). There was no FV Leiden mutation in all the CHD patients and normal controls. CONCLUSION: The Q allele of the R353Q polymorphism of the FVII gene may be a protective factor against myocardial infarction.

Aged↗
PubMed2003

[Treatment of endonasal-encephalomeningocele by transnasal endoscopic surgery].

OBJECTIVE: To inquire into the feasibility of transnasal endoscopic surgery for endonasal encephalomeningocele, and to put forward the basic management guidelines. METHOD: Five cases of endonasal encephalomeningocele were managed by transnasal endoscopic surgery. Different surgical techniques were applied according to the size and shape of skull base defect. At the same time, one-stage repair of skull base defect was achieved by applying muscle, fascia, cartilage and bone. RESULTS: All 5 patients were successfully treated without complication and relapse during 1-5 year follow-up. CONCLUSION: Endonasal type encephalomeningocele can be managed by transnasal endoscopic surgery. If the skull base defect is less than 0.5 cm, it can be repaired by packing muscle and fascia. If the defect is larger than 0.5 cm, the cartilage or bone should be used to repair the skull base.

Adolescent↗
PubMed2003

[Clinical evaluation of risk factors for coronary heart disease].

OBJECTIVE: To explore the relationship between risk factors for coronary heart disease (CHD) and coronary artery lesions. METHOD: Potential risk factors were studied in 341 patients underwent coronary angiography. RESULTS: (1) Coronary angiography showed coronary artery lesions in 214 patients (lesion group), and no lesion in 127 patients (non-lesion group). There was significant difference in age, past history of diabetes, family history of CHD, smoking history, high-density lipoprotein cholesterol (HDL-C), lower-density lipoprotein cholesterol (LDL-C), ratio of total cholesterol to HDL-C (TC/HDL-C), lipoprotein(a) [Lp(a)], fibrinogen (Fbg) and high-sensitivity C-reactive protein (hs-CRP) between two groups (P < 0.05). (2) There was significant correlation between severity of coronary artery lesions and hs-CRP, Lp(a), TC/HDL-C, Fbg, hyperlipidemia, TC, LDL-C and TG (with coefficients of correlation of 0.338, 0.250, 0.241, 0.207, 0.167, 0.147, 0.140 and 0.139; respectively, P < 0.05). (3) Analysis of receiver operating characteristics (ROC) curve for patients with coronary angiography and risk factors for CHD showed that the areas under ROC curve were 0.810, 0.669, 0.626, 0.625, 0.619 and 0.618 for hs-CRP, TC/HDL-C, Lp(a), Fbg, LDL-C and past history of hyperlipidemia, respectively. CONCLUSIONS: Past history of hyperlipidemia was a predictor for occurrence of CHD. Ratio of TC/HDL-C and blood level of Lp(a) could be used as predictors in screening for high blood lipid, which were much stronger than others. It is suggested that hs-CRP had an excellent predictive value in current coronary inflammatory lesions.

Adult↗
PubMed2003

[Clinical evaluation of local application of Merogel after endoscopic sinus surgery].

OBJECTIVE: To study the auxo-action of Merogel (hyaluronic acid) for operative cavity epithelialization after endoscopic sinus surgery (ESS). METHOD: Sixteen patients (32 sides) were observed, in which all sinuses(maxillary, frontal, ethmoid and sphenoid) were operated on by ESS. For the purpose of control study, the left nasal side was used as Merogel group, and right side contrast group. The patients were followed-up for 12 weeks. RESULTS: In Merogel group, the curative rate was 93.75%, improvement rate 6.25%, and average time of epithelialization was 3.4 weeks. In contrast group, the curative rate was 87.50%, improvement rate 12.50%, and average time of epithelialization was 8.3 weeks. It was distinct that in Merogel group, the epithelialization time was shorter than that in contrast group. CONCLUSION: Merogel has auxo-action for operative cavity epithelialization after ESS.

Administration, Topical↗
PubMed2003

Polymorphisms in the coagulation factor VII gene and the risk of myocardial infarction in patients undergoing coronary angiography.

OBJECTIVE: To investigate whether coagulation factor VII (FVII) polymorphisms play a role in the pathogenesis of coronary artery disease (CAD) and/or myocardial infarction (MI) in a series of Hans. METHODS: The Arg(353)Gln and HVR4 polymorphisms of FVII gene were determined in 374 patients undergoing selective coronary angiography by PCR and restriction fragment length polymorphism assay. RESULTS: The FVII genotype distribution was in accordance with Hardy-Weinberg equilibrium. The frequencies of FVII genotypes or alleles did not show significant differences between the CAD group and the controls or between the males and the females. The frequencies of carriers of the Gln(353) allele and (Arg/Gln + Gln/Gln) genotypes were significantly higher in the CAD patients without MI than in those with MI (P = 0.031, odds ratio 0.37, 95% CI: 0.15 - 0.94). However, HVR4 polymorphisms were not significantly different between the two groups (P > 0.05). CONCLUSION: Carrying the F VII Gln(353) gene may be a protective factor against MI in the Chinese Hans.

Asian People↗
PubMed2003

[Sectional anatomy and computer-assisted three-dimensional reconstruction of lateral skull base in normal].

OBJECTIVE: To investigate the sectional anatomy of lateral skull base in normal and provide data for diagnosis and selecting surgical approach of lesions of lateral skull base. METHOD: Three sets of coronal sections with plastination technique was made and investigated for the location, direction and mutual relationship in different section. Signals of some structures were extracted to reconstructed three-dimensional image. RESULT: The section with plastination displayed distinct nerve, muscle, vessel, bone in lateral skull base. The structures of lateral skull base were described in five typical section: the maxillary sinus, pharyngeal orifice of pharyngotympanic duct, foramen ovale, tympanie orifice of pharyngotympanic duet, inner auditory meatus. The three-dimensional images of sphenoid sinus, ethmoid sinus, trigeminal nerve, pharyngotympanic duet and inner carotid artery after extracted the signals in serial sections. CONCLUSION: Sectional anatomy with plastination contributed to understanding complicated anatomic structure including the location and mutual relationship, three dimensional image can vividly display the structure underlying lateral skull base surgery.

Humans↗
PubMed2003

[Study of bleeding during surgery of chronic sinusitis and nasal polyp influenced by preoperative treatment].

OBJECTIVE: To explore the method of reducing bleeding during endoscopic sinus surgery for chronic sinusitis and nasal polyp. METHODS: Bleeding during surgery and the effective rate of two groups patients with chronic sinusitis and nasal polyp were compared (68 cases in group A with preoperative treatment, 30 cases in group B without preoperative treatment). RESULTS: The effective rate between group A(91.2%) and group B (80%) is of significant difference (F = 8.617, P = 0.026); The volume of bleeding during surgery between group A that is (53.2 +/- 41.8) ml and group B that is (97.2 +/- 59.0) ml is of significant difference (F = 27.946, P = 0.002). CONCLUSIONS: Controlling the inflammatory reaction of chronic sinusitis and nasal polyp by preoperative treatment is the most important factor to reduce bleeding while undergoing endoscopic sinus surgery. However, the followings are also important factors to reduce bleeding in endoscopic sinus surgery, such as adequate use of vasoconstrictor in the middle nasal meatus during surgery, the use of deliberate hypotension during surgery, controlling the high risk factors by preoperative treatment and reducing trauma during surgery, etc.

Adolescent↗
PubMed2002

[Retrospective comparative analysis of intranasal endoscopic resection of sinonasal tumors].

OBJECTIVE: To investigate the effectiveness and indication of intranasal endoscopic resection of sinonasal benign tumors. METHODS: A retrospective comparative study was made of intranasal endoscopy among twelve patients with benign tumors and twelve patients with inverting papilloma of the nose and paranasal sinuses between October 1996 and June 2001. A follow-up was made for ten months to five years. RESULTS: Of the twelve cases of benign tumors, five cases of hemangioma including one case of nasopharyngeal angiofibroma, one case of fibroma and one case of neurofibroma as well as one case of benign fibromatosis of nasal ethmoid sinus were completely excised without any evidence of recurrence so far. Of the four patients with ossifying fibromas, two cases with ethmoid sinus invasion underwent successful total removal without any recurrence three years after operation, one case was completely ablated after second procedure and another case had her tumor subtotally resected with symptom remission. Of the twelve cases of inverting papilloma among which two patients had cancerated, eight achieved complete resection at first attempt, and the remaining four cases having either persistence or recurrence of tumor also got cured via endoscopic YAG laser or revision procedure. All these 12 patients except one were followed up for two to five years without any recurrence. CONCLUSION: With excellent visualization, a less operative invasiveness and no scar on face the endoscopic approach appears to be the method of choice for the treatment of some benign tumors including inverting papilloma of nose and paranasal sinuses.

Adult↗