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Biomedical subjects

Y Guo

Publications and source records attributed to Y Guo.

At least 379 records · Page 21Linked to original sources
PubMed1998

[Mutation of breast cancer susceptibility gene in ovarian cancer and its clinical significance].

OBJECTIVE: To detect breast cancer susceptibility gene (BRCA1) mutation in ovarian cancer and to look for correlations between BRCA1 mutation and hereditary ovarian cancer. METHODS: Mutation of BRCA1 gene in 4 patients with hereditary ovarian cancer and 31 patients with sporadic ovarian cancer were screened by polymerase chain reaction-single strand conformation polymorphism analysis with non-isotopic silver staining method. RESULTS: 2 mutations of BRCA1 gene were found in 2 of 3 patients belonged to hereditary breast-ovarian cancer syndrom (HBOC) which were located in exon 2 and 21 respectively. No mutation was found in 31 cases of sporadic ovarian cancer and 1 case of hereditary site-specific ovarian cancer. CONCLUSION: BRCA1 mutation was probably closely related to hereditary breast-ovarian cancer syndrome. Detection of BRCA1 gene mutation was helpful to diagnose HBOC families.

Aged↗
PubMed1998

[Detection of human telomerase activity by telomerase TRAP-ELISA assay].

OBJECTIVE: Telomeric repeat amplification protocol (TRAP) is now a conventional assay for detecting telomerase activity. However, this method presents problems owing to tedious quantification, radioisotopic handling and limited number of samples that can be examined each time. In order to alleviate these inconveniences, a novel telomerase TRAP-ELISA assay for human telomerase activity was developed. METHODS: Telomerase TRAP-ELISA assay is a system based on the combination of PCR-ELISA with TRAP. It was used to detect telomerase activity in 293 cells and RNase-pretreated or heat-treated cells as control. RESULTS: Telomerase activity assayed by TRAP-ELISA was positive when the number of 293 cells examined was 10, 10(2), 10(3), and 10(4). The A(formerly called OD) value depended on the number of 293 cells used in the assay. Telomerase activity of RNase-pretreated or heat-treated cells, and human normal endothelial cell was negative. The result of telomerase TRAP-ELISA was available within one day and was handled without radioisotope. CONCLUSION: Telomerase TRAP-ELISA assay is a non-radioisotopic, fast and quantitative method for detecting human telomerase activity.

Enzyme-Linked Immunosorbent Assay↗
PubMed1998

[P16 expression in lung cancer and its significance].

OBJECTIVE: To study the relationship of suppressor gene p16 and lung cancer for prognosis evaluation. METHODS: Immunohistochemical method was used to detect and analyse the expression of P16 protein of CDKN2 suppressor gene of 76 cases in formalin-fixed, paraffin-embedded tissue specimens of human lung cancer. RESULTS: P16 positive rate was 45%: 52% for 23 of 44 cases of squamous carcinoma and 29% for 7 of 24 cases of adenocarcinoma. Differentiation degree and prognosis of lung cancer were associated significantly with P16 expression. P16 expression was somewhat related to clinical stage. CONCLUSION: P16 gene plays a key role in the prognosis of patients with lung cancer.

Adenocarcinoma↗
PubMed1998

[Hoffmann reflex elicited by magnetic stimulation of S1 nerve roots in the diagnosis of diabetic radiculopathy].

OBJECTIVE: To determine the incidence of radiculopathy in diabetic patients neurophysiologically. METHODS: The H-reflexes were elicited by magnetic stimulation to S1 nerve root at the first sacral foramen (S1 H-reflex) in 40 normal subjects and 41 diabetic patients. The action potentials of the H-reflex were recorded from the soleus muscle. For comparison, a popliteal H-reflex (stimulated at popliteal fossa), and a regular distal sensory and motor conduction of the tibial nerves were simultaneously evaluated. RESULTS: A significant correlation of the peak interval of H wave and M wave (HMI) of the S1 H-reflex with body height and age was confirmed by multiple regression analysis in the normal subjects. The simultaneous regression of the HMI adjusted on age and body height produced the formula as 0.02 x (age) + 0.03 x (height) + 0.92. At 95% normal limits of the significant test, 40.2% HMI and 53.7% amplitude of H waves of the S1 H-reflex, 54.9% latency and 46.3% amplitude of H waves of the popliteal H-reflex, 40.2% SCV and 40.2% amplitude of sensory action potentials were diagnosed as abnormal. CONCLUSIONS: A high incidence rate of diabetic radiculopathy was confirmed to be comparable to that of proximal neuropathy and distal symmetrical sensory polyneuropathy. This suggests that diabetic neuropathy may be related to metabolic and/or vascular disorders.

Adult↗
PubMed1998

[Transnasal endoscopic surgery of skull base].

This article will discuss our experience in managing 54 cases of benign and malignant lesions of skull base using endoscopic transnasal approaches surgery technique since 1991, emphasizing general principles for management and specific details for individual lesions including cerebrospinal fluid rhinorrhea repair, optic nerve decompression, obliteration of empty sella, pituitary tumor resection, and malignant tumor resection. In the result, endoscopic transnasal approach were used successfully in all the cases, it indicates that the new technique is a safe, valuable and efficient procedure for management of some lesions of skull base.

Adolescent↗
PubMed1998

[Characteristics of radiofrequency current catheter ablation in the treatment of elderly patients with supraventricular tachycardia].

To study the effects and characteristics of radiofrequency current catheter ablation (RFCA) in treatment of elderly patients with supraventricular tachycardia (PSVT), fifty-three elderly patients and fifty non-elderly patients with PSVT were included in this study. RFCA were performed in both groups. The group of elderly patients included 26 patients with atrioventricular nodal reentrant tachycardia and 27 patients with atrioventricular reentrant tachycardia due to 29 atrioventricular accessory pathways (Aps). Twenty-one patients were accompanied with hypertension and coronary heart diseases and 5 sick sinus syndrome cases in the elderly group. All patients in both groups were treated successfully with RFCA. The procedure time of ablation of slow pathway in elderly group was shorter than that of the non-elderly group (P < 0.01). A mild symptom of arterial thrombosis was found in 2 cases of the elderly group after treatment and was cured with aspirin. These results suggest that PFCA is very effective and safe in the treatment of elderly patients with PSVT, especially for patients accompanied with sick sinus syndrome.

Aged↗
PubMed1998

[Comparative studies of ciliary epithelial morphological and radiologic findings in the osteomeatal complex].

In this study, we evaluated quantitatively preoperative coronal CT scan in 30 nasal cavities of 22 patients with chronic sinusitis who underwent functional endoscopic sinus surgery. The ciliated area of the osteomeatal complex (OMC) from these patients was quantitatively observed by scanning electron microscope and image analysis. Our results showed a positive correlation between ciliary epithelial pathological changes in OMC and disease degree of this area in CT scan.

Adult↗
PubMed1998

[Diagnosis and treatment of Ramsay Hunt syndrome (a report of 39 cases)].

Thirty-nine cases with Ramsay Hunt syndrome were presented, in which 23 cases were firmly diagnosed early, and others were misdiagnosed to be Bell's palsy in 9 cases, sudden sensorineural hearing loss in 5, herpes zoster pharyngitis in 1 and acute suppurative otitis media in 1, respectively. All patients were treated with prednisone or dexamethasone for 3 weeks. The results of treatment were as follows: complete recovery in 27 cases, residual facial paralysis in 12 patients, in which 11 had sensorineural hearing loss. We concluded that: 1. When patients present idiopathic facial paralysis associated with objective sensorineural hearing loss, Hunt syndrome should be suspected even in the absence of vesicles. 2. Treatment with steroid and antiviral agent is needed. There is no significant difference in the effects between oral and intravenous steroid therapy. 3. The poor prognosis may relate with severe facial paralysis accompanying severe hearing loss. 4. Acoustic stapedius reflex in patients with mild or no hearing loss is useful for defining the involved sites and evaluating the prognosis.

Adolescent↗
PubMed1998

[Detection of ET-1, TNF-alpha, oxidative radicals in sera of asthmatics and in sera and lung tissue of asthmatic guinea pigs].

OBJECTIVE: To investigate the role of the ET-1, TNF-alpha and oxidative radicals of MDA and SOD in the pathogenesis of asthma and the effect of the nitric oxide synthase inhibitor, L-NAME to above factors. METHOD: ET-1 was detected by the radio-immunoassay and TNF-alpha was detected by ELISA, SOD and MDA were detected by using thiobarbituric acid method. RESULT: The contents of ET-1, TNF(and MDA in the serum of the asthmatic patients and in the serum and lung tissue of asthma models of guinea pigs were significantly increased, in the contrast, the content of SOD was decreased compared with those in the controls(P < 0.01). All the changes in the serum and in the lung tissues of the asthma models of guinea pigs returned to the levels of the controls by dexamethasone inhalation or L-NAME by intraperitoneal injection. CONCLUSION: ET-1, TNF alpha and the oxidative radicals and NO may play important roles in the pathogenesis of asthma, L-NAME, which is similar to the dexathamethsone, may either decrease the content of NO or decrease the content of ET-1, TNF alpha and oxidative radicals in asthma.

Adult↗
PubMed1998

[The clinical diagnostic significance on detection of Mycoplasma pneumoniae antigen in upper respiratory tract epithelium].

OBJECTIVE: To investigate the early diagnosis of pulmonary mycoplasma pneumoniae (MP) infection by detection of MP antigen in upper respiratory tract epithelium. METHOD: A prospective study on respiratory MP infection was conducted in 110 patients with acute respiratory infection from February 1996 to November 1997 in our hospital. Upper respiratory tract epithelia were collected from gargle and MP antigen was detected by immunofluorescent assay (IFA). At the same time, serum samples were taken and immunoglobulin M (IgM) fractions of specific antibody to MP were assessed by the same method in 70 of 110 patients. Moreover, clinical features, cold agglutination test and chest X-ray were also collected for analysis. RESULT: The positive rates of MP antigens and IgM antibody were 17% and 20%, respectively, while the titer on cold agglutination test > 1:8 in only two patients. The clinical features in patients with positive MP antigen and/or IgM antibody were similar to that of pulmonary MP infection. CONCLUSION: Examination of MP antigen in upper respiratory tract epithelium collected from gargle combined with serum specific IgM antibody is a good method for the early diagnosis of pulmonary MP infection.

Adolescent↗
PubMed1998

[Diagnosis and surgical treatment of pituitary microadenoma].

OBJECTIVE: Through the experiences of clinic picture and the radiologic characteristics of eleven cases of micropituitary adenomas, the early diagnosis and surgical indications were discussed. METHODS: Intensified CT and MRI were used to compare their significances in the diagnosis of micropituitary adenomas. Kaltai incision of the nares and transsphenoidal approach were adopted in these cases. RESULTS: The bulging of the upper border of the pituitary gland and the shifting position of the pituitary stalk observed in the intensified MRI are the pathognomonic signs for the diagnosis of micropituitary adenoma. The operation was stopped due to hemorrhage in one case. The average following up was 3.2 years past operative death in the second month in one case, operative failure in one case and loss of following up in one case. CONCLUSION: Strict selection of surgical indications must be done necessary after careful study of MRI.

Adenoma, Chromophobe↗
PubMed1998

[Chemical research on stilbenes from Veratrum macckii Reg].

OBJECTIVE: To study the components in rhizome of Veratrum macckii. METHODS: Column chromatography and preparative thin layer chromatography with silica gel were employed for the isolation and purification of constituents. The structures were elucidated by IR, MS and 1H-NMR analysis. RESULTS: Two compounds were obtained and elucidated as resveratrol and 2,3',4,5'-tetrahydroxystilbene. CONCLUSION: The two compounds were separated from V. macckii for the first time.

Drugs, Chinese Herbal↗
PubMed1998

[Model of human nasal gland cells cultured in collagen gels].

OBJECTIVE: To establish a culture model of human nasal gland (HNG) cells in collagen gels. METHOD: The HNG cells were cultured in collagen gels. RESULTS: The HNG cells cultured in collagen gels showed 3-D outgrowth. After one week culture, the HNG cells developed ductal projections, the sections of collagen gel culture examined by light microscopy showed cross sectional area of tubules with a lumen containing secretory products. The cells contained numerous secretory granules. Electron microscopy showed 3-D cultured HNG cells forming a well defined lumen inside the tubular formation. These cells were polarized and interconnected by junctional complexes and possessed extensive microvilli along all their luminal border. Secretory products in the lumen and the cells located close to the luminary surface were intensely stained blue by AB-PAS staining. Immunohistochemical staining of cells labeled with a rabbit antiserum against human lysozyme showed 90% positivity. CONCLUSION: These data indicated that HNG cells altered their phenotypes when cultured in vitro and changed from differentiated serous and mucous cells toward intermediate seromucous cells.

Cell Differentiation↗
PubMed1998

EMG study in the diagnosis and differential diagnosis of lipid storage myopathy.

Clinical, electromyographic and pathological features were studied in 18 patients with lipid storage myopathy (group I) and 18 patients with polymyositis and dermatomyositis (group II). The results showed a remarkable lower spontaneous activity(SA) incidence (14%) in group I than that (55%) in group II; 46% and 34% short-duration motor unit potentials(MUAPs) with polyphasic potentials and 74% and 71% short-duration MUAPs without polyphasic potentials respectively; the percentages of increased polyphasic MUAPs were same in the two groups. The reduced or pathologic interference patterns accounted for 61% in the group I and 50% in group II. Increased CPK, LDH and HBD were also found in both of them. It is suggested that the lipid storage myopathy may be diagnosed when patients have muscle weakness and myalgia with short-duration and low-amplitude and polyphasic MUAPs without or with occasional spontaneous activities, and increased CPK, LDH and HBD.

Adolescent↗
PubMed1998

[Primary epididymal tumors].

OBJECTIVE: To improve the diagnosis of primary epididymal tumors. METHOD: In 23 primary epididymal tumors (22 benign and 1 malignant), 14 were adenomatoid tumors, 6 were leiomyomas, 1 was multiple fibrous pseudomonas and 1 was sclerosing hemangioma. Epididymal adenocarcinoma was seen in a 57-year-old man. RESULT: Epididymal tumors might be easily misdiagnosed as epididymal tuberculosis, chronic epididymis and spermatocele. Apart from certain benign clinical characteristics, benign epididymal tumors could be diagnosed by B-ultrasonography and aspiration biopsy. Most malignant tumors of epididymis presented as rapidly growing scrotal masses and cured by the removal of tumors or the whole epididymis of the same side. 19 of 22 cases were free from recurrence. CONCLUSION: Malignant epididymal tumors should be treated as malignant tumors of testis and their prognosis is extremely poor.

Adenocarcinoma↗