Biomedical subjects

S Huang

Publications and source records attributed to S Huang.

At least 379 records · Page 21Linked to original sources

PubMed1997

[10-year epidemiological study on rheumatic diseases in Shantou area].

22,049 adults were surveyed in a ten-year epidemiological study. The frequency of common rheumatic symptoms in Shantou population was much lower than that in northern China. The prevalence of ankylosing spondylitis, rheumatoid arthritis, osteoarthritis, osteoporosis and gout was 0.20%-0.32%, 0.20%-0.26%, 8.3%-10.8%, 12.4% and 0.15%-0.17% respectively. The frequency of HLA-B27 was 4.1% among general population and 90.6% in ankylosing spondylitis. The most commonly involved sites of osteoarthritis were lumbar spine, neck, and knee; but hands and hip were rarely involved. 85% subjects under investigation were found to be short of calcium intake. The differences between the north and the south of China in the prevalence of rheumatic symptoms may be related to the diversities in consciousness of seeking medical advice, reduction of bone content, climate and ergonomics.

Adult↗

PubMed1997

[Study on measures to increase diagnostic accuracy of FNAC of breast masses].

OBJECTIVE: To study the measures capable of increasing the diagnostic accuracy, reducing misdiagnosis as well as giving a full play to fine needle aspiration cytology(FNAC), in the diagnosis of breast masses, and to standardize the diagnostic report form. METHODS: Totally 1629 cases of FNAC were performed and 444 cases of them were checked with the histological diagnosis. RESULTS: The sensitivity of diagnosis of malignant tumors in 307 cases, the specificity of diagnosis of benign lesions in 137 cases and the overall accuracy of diagnosis were 95.8%, 98.5% and 96.6% respectively. The false negative rate, potential false positive rate and the overall misdiagnostic rate were 4.2%, 1.5% and 3.4% respectively, while no case of false positive diagnosis was found. CONCLUSIONS: We believe that: (1) It is very important to use a fine aspirator, to make smears of high quality, to carry out an integrated working procedure and to put into effect a conscientious check over cytological appearance with histological diagnosis. (2) The diagnositc report form introduced in "the uniform approach to breast fine needle aspiration biopsy" by Bethesda specialists is worthy of reference. (3) FNAC can further play important roles in the diagnosis and treatment of breast masses.

Biopsy, Needle↗

PubMed1997

[Chronic airway inflammation and atopic features in cough variant asthma].

OBJECTIVE: To elucidate the chronic airway inflammation and atopic features in 17 patients with cough variant asthma (CVA). METHODS: (1) Allergen skin prick test, and the atopy index (AI) calculation. (2) Fiberoptic bronchoscopy, inflammatory score of airway membrane under bronchoscopy. (3) Biopsy of the airway membrane and calculation of the eosinophil infiltration. (4) Bronchoalveolar lavage, classification of various cells in the BALF. (5) House dust mite and rabbit antihuman IgE induced histamine release from mast cell. The results were compared with those in 9 patients with typical asthma (Group 8) and 7 normal subjects (Group C). RESULTS: The number of EOS and mast cells in BALF and the AI of CVA group were found higher than in control group. CONCLUSION: (1) Similar to typical asthma, IgE dependent type I allergic reaction plays an important role in the pathogenesis of CVA. (2) Chronic inflammation including eosinophil infiltration was shown in airway membrane in CVA. (3) Bronchial hyperresponsiveness and chronic inflammation of the airway membrane in CVA are less severe than those in typical asthma. (4) In patients who are in difficulty of making a diagnose of CVA clinically. BAL and biopsy of the bronchial membrane will help to make a definite diagnosis.

Adult↗

PubMed1997

[L-arginine and nitric oxide have effects on glomerulus hyperperfusion of early diabetic rats].

We used streptozotocin (STZ) to induce the animal model of diabetes mellitus in rats. On the 7th and 14th days of induction, kidney disorder, the levels of NO3- in plasma and tissue homogenate in different periods were observed. The NO3- levels in relation to the application of L-arginine (L-Arg) were also noted. The results showed that the kidney weight/body weight ratio significantly increased in different periods (P < 0.05). On the 7th day profuse proteinuria appeared and it markedly increased on the 14th day: creatinine clearance rate (Ccr) significantly raised, too (P < 0.005). The NO3- levels in plasma and tissue homogenate were getting higher with time. The level of NO3- significantly increased after L-Arg was perfused. It indicated that kidney disorder was present at the early stage of diabetes, and the raised Ccr indirectly indicated the increase of glomerular filtration rate. These suggest that NO3- and L-Arg may be important mediums which have effects of hyperfiltration and hyperperfusion of glomerulus.

Animals↗

PubMed1997

[Application of ultrasound biomicroscopy in diagnosis of anterior segment vitreoretinal disorders].

PURPOSE: To investigate the diagnostic value of ultrasound biomicroscopy(UBM) in anterior segment vitreoretinal disorders(ASVD). METHODS: 60 eyes of 58 sequential patients were examined with UBM. The ultrasound biomicroscopic images were compared with the results of clinic examination, B-scan ultrasonography and the finding during surgery to evaluate the reliability of UBM for ASVD. RESULTS: UBM allows structural details of the conjunctiva, rectus muscle, sclera, uvea, retina and vitreous to be visualized at microscopic resolution in living eye. The area of UBM may cover from cornea to vitreous base, partially to the equator of eye. A variety of the changes of ASVD were imaged in 60 eyes, including retinal detachment in 43 eyes, retinal circumferential contraction in 29 eyes, retinal anterior displacement in 24 eyes, vitreous opacities or fibrosis in 57 eyes, ciliary orchoroidal detachment in 26 eyes, ciliary nonpigmented epithelial detachment in 6 eyes, proliferative tissue at the sclerotomy site in 9 eyes, retinal neoplasm in 2 eyes, ciliary cyst in 6 eyes, proliferation of peripheral silicone oil in 8 eyes, silicone oil emulsification in 7 eyes and vitreous foreign body in 2 eyes, respectively. CONCLUSIONS: Our studies showed the feasibility of UBM for ASVD not visible by current techniques UBM can be used for the diagnosis, differential diagnosis and the instructive treatments of ASVD.

Adult↗

PubMed1997

[Experimental study on aqueous areca nut extracts inducing oral submucous fibrosis in rats. I. Observation of histomorphology].

The purpose of this study was to establish the animal model of oral submucous fibrosis (OSF) in buccal mucosa of SD rats by submucosa injecting and surface painting aqueous areca nut extracts (AANE). The animals of all groups were killed randomly in the 12th, 16th, 22nd and 28th week. The buccal mucosae were collected, and were detected by light microscope and transmission electron microscope. The results were obtained: at different stages, the OSF-like lesions appeared in different degrees among some animals of the model groups, including atrophic epithelium with loss or partial loss of rate pegs, inflammation, accumulation and disorder of collagen fibre in juxta-epithelial region, along with concomitant muscle degeneration. The lesions didn't reverse obviously themselves after the authors stopped using AANE. Histomorphologic changes didn't appear in any animal of the control groups. The results indicated that the typical and stable OSF animal model were induced rapidly by submucosa injecting and surface painting AANE.

Animals↗

PubMed1997

[Experimental study on aqueous areca nut extracts inducing oral submucous fibrosis in rats. II. Effection of mast cells on collagen metabolism].

The effection of mast cells (MC) on collagen metabolism of oral submucous fibrosis (OSF) induced by aqueous areca nut extracts (AANE) in rats was studied by transmission electron microscope, histochemical and biochemical analyses. The results revealed that there was a close relationship between MC and fibroblats (FB) in the pathogensis of OSF; MC which appeared in the buccal mucosa in the model groups increased significantly and became more active in the function. A great deal of collagen compacted in the buccal mucosa in the model groups. The contents of tissue hydroxyproline (Hyp) in the model groups were obviously higher than those in the control groups. Moreover, the longer the time of irritation continued, the higher the contents were. The number of MC had a higher positive correlation with the contents of tissue Hyp at the same time. Total serum Hyp had no significant difference among all the groups and any stages. The results indicated that some aqueous components of areca nuts might disturb collagen metabolism by accumulation and activation of MC.

Animals↗

PubMed1997

[A study on the frequency of sister chromatid exchanges in patients with oral submucous fibrosis in peripheral blood lymphocytes].

The frequency of sister chromatid exchanges (SCEs) in peripheral blood lymphocytes in the patients (n = 27) with oral submucous fibrosis (OSF) with the habit of chewing areca nuts were determined by BrdU-Giemsa staining. The healthy persons (n = 14) with the same habit and the normal controls without the habit (n = 44) were studied at the same time. The results showed that the frequency of SCEs in the first two groups were obviously higher than that in the last one (P < 0.001). The frequency of SCEs in the patients were also higher than that of the healthy persons with the habit (P < 0.001). These suggest that there are some substances in the areca nuts which can induce the mutation and/or malignant transformation of cells. The habit of chewing areca nuts might seriously disturb the stability of chromosome. OSF is a precancer condition. The occurrence of it perhaps has some hereditary background or genetic susceptibility.

Adult↗

PubMed1997

[Transduction of antisense RNA of MHC-II gene into CD3+ cord blood stem/progenitor cells inhibits the expression of HLA-DR antigen].

OBJECTIVE: To explore whether the antisense RNA of HLA-DR gene could modulate the expression of the gene and reduce the immunogenicity of cord blood (CB) cells. METHODS: A retroviral vector encoding antisense RNA of HLA-DR gene was constructed and transducted into packaging cell line PA317 by lipofectin. CD34+ hematopoietic stem cells/progenitors were sorted and enriched by MACS. RESULTS: A high titer (1 x 1095) cfu/ml) helper-free,virus producing cell PA317 was obtained. The vector was identified by blot hybridization and mapping of restriction points. The CD3+ CB cells were infected by the supernatant of the viral cultures. The G418-resistant clone was demonstrated to express the antisense RNA of HLA-DR gene by RT-PCR technique. The expression rate of HLA-DR antigen on CB cells was 28%, which was apparently lower than that of the control (45%) with an inhibition rate of 38.25%. CONCLUSION: The introduction of antisense RNA of HLA-DR gene into CB hematopoietic stem cells can successfully decrease the expression of HLA-DR antigen. These studies provide evidences for the prevention and treatment of GVHR in clinical CB transplantation.

Animals↗

PubMed1997

[Identification of alpha-globin gene organization using long PCR].

OBJECTIVE: To identify the abnormalities of alpha-globin gene organization. METHODS: Complementary DNAs to the sequences of the up-stream of alpha2-globin gene and the down-stream of alphal globin gene, respectively were designed as long PCR primers, DNA from 7 individuals with normal or abnormal alpha-globin gene organizations were analyzed by long PCR procedure. RESULTS: The normal alpha-globin gene organization (alphaalpha) was identified to have a 6.4kb amplified fragment. The rightward type of alpha-globin gene deletion (alpha(-3.7)) resulted in a 2.6kb amplified fragment; the Southeast Asia type of alpha-globin gene deletion (- - SEA) had no amplified fragment and alpha-globin gene triplication (alphaalphaalpha(anti3.7)) showed a 10.2kb amplified fragment. CONCLUSION: Long PCR provides a new method for the rapid detection of the abnormalities of alpha-globin gene organization.

Asia, Southeastern↗

PubMed1997

[Determination of R- and S-mephenytoin in human urine by gas chromatography].

The levels of R- and S-mephenytoin in human urine were determined by chiral capillary gas chromatography with nitrogen-phosphorus detector. The conditions of the chromatography and detection included a chiral capillary column (Chirasil-Val, 25 m x 0.25 mm i.d., Alltech), column temperature (T) 190 degrees C, injector T 220 degrees C, detector T 240 degrees C, and the flow-rates of 0.85, 3.5 and 120 mL/min for nitrogen, hydrogen and air respectively. Based on the above conditions, the satisfactory separation of R- and S-mephenytoin was gained, and other interference from urine sample was not found. The linear curves for both tested compounds ranged between 12.5 and 2500 microg/L, with a minimum detectable concentration of about 6 microg/L. Because of its simplicity, rapidity, sensitivity and accuracy, this method has been extensively used for testing metabolic ability of S-mephenytoin polymorphic oxidation in the Chinese populations and for the determination of the activity of hepatic drug-metabolizing enzyme CYP2C19 using mephenytoin S/R ratio of the urine samples of subjects as an indicator.

Anticonvulsants↗

PubMed1997

[Fluorescence spectra study on 2, 3, 7, 8-tetrachloro-n-ethyl-phenothiazine].

In this paper we gave been discussed the variation law of fluorescence intensity of 2, 3, 7, 8-tetracloro-N-ethyl-phenothazine under different conditions. The experimental results show the best emit light system of fluorescence. It has theoretical significance and practical value on raising seneitivity of organic photoconductor.

English Abstract↗

PubMed1997

[Study on fluorescence method of pefloxacin].

Pefloxacin is a new kind of antibiotic. In this paper, a sensitive fluorescence method has been developed for the analysis of Pefloxacin. It has stronger fluorescence excitation. The fluorescence of Pefloxacin was measured at excitation wavelength 282nm and emission wavelength 440nm. The method is highly sensitive with lower limit of detection, calibration curves were linear between 1 x 10(-9) - 1 x 10(-6)mol/L, with a regression coefficient of 0.9999. At the same time, recoveries of pefloxacin in Human serum Albumin and Urine are 95% and 105% respectively.

Anti-Infective Agents↗

PubMed1997

Characteristics of risk-taking behaviors, HIV and AIDS knowledge, and risk perception among young males in southwest China.

A cross-sectional survey was undertaken to describe risk-taking behaviors and to assess the knowledge and risk perception of HIV and AIDS among young males aged 18 to 29 years in 82 villages in Longchuan, Yunnan, China, in 1994. Information on demographic, behavioral, and drug-using factors, and knowledge of HIV transmission and prevention, and risk perception was collected using an interviewer-administered anonymous questionnaire. A total of 1,548 individuals were interviewed and 433 drug users, including 52 nonsharing injectors and 140 sharing injectors, were identified. Over half the individuals scored 0 on HIV knowledge, but knowledge was greater among nonsharing drug injectors. Most drug injectors had initiated drug injection after 1990. The reported incidence continues to increase in all three major ethnic groups. Sharing of equipment was common (73%) among injectors. Drug users were four times more likely to have had premarital or extramarital sex, but condoms were used by only 2.5%. Thus, factors promoting spreading of HIV are common in this area. We recommend that a community-based intervention program, targeting both young men and women, be implemented and evaluated in Longchuan as soon as possible.

Acquired Immunodeficiency Syndrome↗

PubMed1997

Hemorrhagic complications of long-term anticoagulant therapy in 7 patients with systemic lupus erythematosus and antiphospholipid syndrome.

OBJECTIVE: To describe the presentation, course, and management of serious hemorrhagic complications of anticoagulant therapy for patients with antiphospholipid syndrome (APS). METHODS: Charts of patients identified with serious bleeding complications from anticoagulation for APS were reviewed. RESULTS: Patients included 6 women and one man with systemic lupus erythematosus (SLE) and one woman with primary APS. One patient had 3 separate hemorrhagic events. There were 6 episodes of subdural hematoma in 5 patients, one episode of pericarditis with tamponade, one episode of hemoptysis, and one episode of ovarian hemorrhage. In 2 patients, symptoms related to hemorrhage were initially attributed to active SLE. Duration of anticoagulation was between one month and 10 years at the time of bleed. International normalized ratio (INR) and prothrombin time were above the intended range in 6/9 episodes. There were no deaths and no permanent sequelae due to bleeding. Anticoagulant therapy was resumed in 6/7 patients. CONCLUSION: The management of APS must include vigilance, patient education, and anticoagulation to maintain the INR between 3 and 3.5. To prevent hemorrhagic complications, low molecular weight heparin is an option that deserves further study.

Adolescent↗

PubMed1997

Expression of interleukin-8 by human melanoma cells up-regulates MMP-2 activity and increases tumor growth and metastasis.

Expression of interleukin-8 (IL-8) by human melanoma cells correlates with their metastatic potential. Moreover, UV-B irradiation of primary cutaneous melanoma cells induces IL-8 mRNA and protein production and increases both tumor growth and metastasis in nude mice. Although IL-8 has been shown to be an angiogenic factor, the biological consequences of increased IL-8 production by melanoma cells and the role of IL-8 in the metastatic process remains unclear. The purpose of this study was to determine the role of IL-8 in tumor growth and metastasis of human melanoma cells. Nonmetastatic SB-2 melanoma cells with negligible levels of IL-8 were transfected with IL-8 cDNA and subsequently analyzed for changes in their tumorigenic and metastatic potential. Enforced expression of IL-8 rendered the melanoma cells highly tumorigenic and increased their metastatic potential as compared with parental and control transfected cells. The IL-8-transfected cells displayed up-regulation in M(r) 72,000 collagenase type IV (MMP-2) mRNA and collagenase activity and increased invasiveness through Matrigel-coated filters. Moreover, when the MMP-2 promoter was linked upstream of the chloramphenicol acetyltransferase (CAT) reporter gene, CAT activity was up-regulated in IL-8 but not in control transfected cells, suggesting that IL-8 is involved in MMP-2 gene transcription. Activation of type IV collagenase by IL-8 can enhance the invasion of host stroma by the tumor cells and increase angiogenesis and, hence, metastasis.

Animals↗

PubMed1997

Comparison of intravenous retention of fentanyl and lidocaine on local analgesia in propofol injection pain.

BACKGROUND: With a tourniquet on arm for arresting venous blood flow, we evaluated the efficacy of intravenous (i.v.) retention of fentanyl and lidocaine in reducing the pain on i.v. propofol injection during general anesthesia. METHODS: One hundred and twelve patients were studied. Following a venous occlusion by a tourniquet inflated to 70 mmHg, patients in Group A (n = 38) received normal saline (NS) 3 ml, while those in Group B (n = 37) and in Group C (n = 37) respectively received fentanyl 150 micrograms or 3 ml and 2% lidocaine 3 ml (60 mg). The venous retention of drug was maintained for 1 min, followed immediately by tourniquet release and propofol 100 mg i.v. injection over 20 s. RESULTS: Both fentanyl and lidocaine treatments (Groups B and C) were significantly better than placebo (Group A) in reducing pain on propofol injection (p < 0.005). Lidocaine 60 mg was more effective than fentanyl 150 micrograms in reduction of pain associated with i.v. propofol (p < 0.001). Injection of fentanyl itself caused pain in 28% of patients as compared to 2% in the lidocaine group. Mild local skin erythema was noted in 14% of patients with fentanyl venous retention versus 0% of patients with lidocaine venous retention. CONCLUSIONS: Intravenous retention of fentanyl 150 micrograms, although less effective than that of lidocaine (p < 0.001), showed local analgesic effect in reducing the pain on propofol injection. The hypothetic mechanisms of action were speculated.

Adolescent↗

PubMed1997

Construction of mammary gland-specific expression vectors for human clotting factor IX and its secretory expression in goat milk.

Two expression vectors comprised of mouse matrix attachment regions (MARs), bovine beta-casein gene sequence, human factor IX (hFIX) minigene, and cDNA, pMCIXm and pMCIX, were constructed for the purpose of a mammary gland bioreactor. A secretory expression system of hFIX protein in milk was made using stearylamine (SA) liposome to transfect plasmid DNA directly into the mammary gland lobule of a lactating goat. The highest production of hFIX in goat milk was 13.7 ng/ml 3 days after transfection, and the hFIX production in the goat mammary gland transfected with pMCIXm containing hFIX minigene was obviously higher than that transfected with pMCIX containing hFIX cDNA. Activity immuno-analysis and the barium citrate absorption method showed that > 90% hFIX protein in milk appeared to be a gamma-glycosylated and biological activity. This result confirmed the validity of the constructed vectors for further transgenic study, and this assay could also find its success in the evaluation of a foreign gene expression and secretion in the milk as a rapid detection system using liposome to transfect DNA directly into the goat mammary gland.

Animals↗