Biomedical subjects

S Wang

Publications and source records attributed to S Wang.

At least 757 records · Page 42Linked to original sources

PubMed1999

[The detection of T-cell receptor gene rearrangement in myelodysplastic syndromes].

OBJECTIVE: To analyse the T cell receptor (TCR) gene rearrangement in myelodysplastic syndromes (MDS). METHODS: Polymerase chain reaction (PCR) was used to detect the TCRVgammaI-Jgamma gene rearrangement in 36 cases of MDS. RESULTS: 8 cases (22.2%) were found to have TCRVgammaI-Jgamma gene rearrangement. The TCR gene rearrangement positive rate was higher in RAEB, CMML and RAEBT subtypes than that in RA and RAS subtypes (P < 0.05). The average time MDS evolving to acute leukemia was shorter in the MDS patients with TCRVgammaI-Jgamma for gene rearrangement than that in patients without (P < 0.01). CONCLUSION: TCR gamma gene rearrangement can also be found in some MDS patients and the detection of TCRgamma gene rearrangement might be helpful to identify the prognosis and the development of MDS.

Adolescent↗

PubMed1999

[External valvuloplasty for deep venous valve insufficiency of legs].

OBJECTIVE: To study and evaluate the therapeutic effects of external valvuloplasty for deep venous valve insufficiency of the legs. METHODS: External valvuloplasty of the femoral vein valve was performed in 26 patients (37 legs) with deep venous valve insufficiency of the legs. Among them, 12 were male and 14 were female. These patients ranged in age from 16 to 69 years (x +/- s, 50.8 +/- 10.0). External valvuloplasty of the first pair of the superficial femoral vein valve was carried out in all the legs. External valvuloplasty of the second pair of the superficial femoral vein valve was added in 7 legs and valvuloplasty of the common femoral vein valve in 6 legs. RESULTS: Venous claudication, swelling, aching disappeared in 81.1% patients (30/37), obviously improved in 18.9% (7/37) and varicose veins disappeared in all legs. Ulcer healing was seen in 7/9 patients. Deep venous valve sufficiency was demonstrated in 89.2% patients (33/37), and reflux I degrees - II degrees in 4 legs by color Doppler. CONCLUSIONS: External valvuloplasty is effective in treating deep venous valve insufficiency of the legs.

Adolescent↗

PubMed1999

[Biologic behavior and prognosis of patients with gastric cancer in young persons].

OBJECTIVE: To explore the relationship between the biological behavior and prognostic factors in treating gastric cancer of young persons by various surgical methods. METHODS: 89 young patients with gastric cancer aged 35 years or less were analyzed. RESULTS: The resectable rate was 73.0% (65/89), radical resectable rate 48.3% (43/89), and palliative resectable rate 24.7% (22/89). The 5-year survival rate was 24.7% (22/89) and 48.8% (21/43) for the radical group. Biological characteristics included infiltrated, diffused growth, lymph node metastasis, female predominance. CONCLUSIONS: The biological behavior of gastric cancer in young persons is poor. Early management gastric cancer and radical operation combined with complex treatment are essential.

Adult↗

PubMed1999

[Microsurgical treatment for meningioma of falco-tentorial junction].

OBJECTIVE: To study the clinical characteristics, neuroimaging presentations, operative warming events and the results of surgical treatment of meningioma of the falco-tentorial junction. METHODS: The clinical data of 14 patients with meningioma of the falco-tentorial junction were retrospectively analysed. Preoperative examinations included head CT in all patients, DSA in 10, MRI in 6, and MRA in 2. 10 patients was operated on via suboccipital transtentorial approach, of which, operated-side-up position in 7 patients, three-quarter prone operated-side-down position in 3. Three 3 patients was operated on via trans-infratentorial-supracerebellar approach. One via trans-lateral-ventricle trigone approach. RESULTS: Of 14 patients, 12 received total removal of meningioma and 2, subtotal resection. Intracerebral hematoma occurred postoperatively in 2 patients and, intratumoral-residual-cavity hematoma in 1. Two patients' hematomas were eliminated, and another patient's hematoma was conservatively treated. Average follow-up period was 4.5 years. All patients resumed their normal work and study. One patient had permanent homonymous hemianopsia, and one had trochlear paralysis. CONCLUSIONS: Meningiomas of the falco-tentorial junction were operable. With some acceptable morbidity, perfect surgical results can be obtained.

Adolescent↗

PubMed1999

[The relationship between operation on gastrointestinal cancer and single cells metastasis via portal vein].

OBJECTIVE: To confirm the effect of radical operation on single cells metastasis of gastrointestinal cancer. METHODS: One hundred and seventy two patients with gastrointestinal cancer were divided randomly into group I (111 cases, ordinary operation) and group II (61 cases, operation after ligation of drained vessels). Catheters were inserted into the portal vein during operation. Blood was aspirated and contrifugated. Anti-EMA monoclonal antibody marked the cancer cells, which were shown by ABC immunohistochemical staining. RESULTS: In the examinate group, 72 cases of gastrointestinal cancer were found positive cells among 111 cases (positive rate 64.9%). In the control group, 61 cases were tested and 13 cases were found positive cells (positive rate 21.3%) with a highly significant difference between the two groups (P < 0.005). CONCLUSIONS: Ligating the relative blood vessel before the radical operation can prevent single cancer cells from metastasis via portal vein.

Adult↗

PubMed1999

[Changes of interleukin-2 and soluble interleukin-2 receptor serum level and multiple organ dysfunction syndrome in severely traumatic patients].

OBJECTIVE: To evaluate the role in the changes of interleukin-2 (IL-2) and soluble interleukin-2R (sIL-2R) serum level in the mechanism of post-traumatic multiple organ dysfunction syndrome (MODS). METHODS: 59 severe traumatic patients were divided into MODS group (n = 24) and non-MODS group (n = 35) according to the occurrence of MODS after trauma. The changes in IL-2 and sIL-2R serum level were observed by enzyme linked immunoabsorbed assay (ELISA). Sera from 30 healthy individuals were used as normal controls. RESULTS: The serum level of sIL-2R was increased and that of IL-2 decreased in 59 traumatic patients. These changes were more marked in the MODS group than in non-MODS group (p < 0.05). CONCLUSIONS: The changes in IL-2 and sIL-2R serum level after trauma might participate in the mechanism of post-traumatic MODS.

Adolescent↗

PubMed1999

[Intestinal blood perfusion improved by early enteral feeding in burned rat].

OBJECTIVE: To explore the mechanism of intestinal blood perfusion improved by early enteral feeding after burn injury. METHODS: Wistar rats were inflicted with 30% total body surface area full thickness flame burn and randomly divided into three groups: burned control (B), burned and early feeding (EF), and normal control (C). The content of endothelin (ET), nitric oxide (NO), vasoactive intestinal peptide (VIP), and intestine mucosal blood flow (IMBF) were determined at postburn 0, 3, 6, 12, 24, 48 hours. RESULTS: The content of ET, NO, VIP in small intestine as well as the ratio of ET/NO, ET/VIP were increased significantly and the IMBF was decreased markedly postburn. In EF group, ET, ET/NO and ET/VIP were significantly lower (P < 0.05, P < 0.01), and NO, VIP as well as IMBF were higher than those in B group (P < 0.05, P < 0.01). There were negative correlation between ET/NO, ET/VIP and IMBF (r(1) = -0.95, P < 0.01; r(2) = -0.87, P < 0.01). CONCLUSIONS: The mechanism of intestinal blood perfusion improved by early enteral feeding may be correlated with increased NO, VIP and decreased ET induced by foods stimulating intestinal nerve.

Animals↗

PubMed1999

[Gamma delta T cells and their receptor Vdelta gene rearrangement in transitional mucosa of rectal carcinoma].

OBJECTIVE: To observe gamma delta T cells and their receptors Vdelta gene rearrangement expression in the transitional mucosa of rectal carcinoma, and to investigate their relations with local tumor recurrence. METHODS: In 13 patients with rectal carcinoma, gamma delta T cells in transitional mucosa were measured with two-color immunofluorescent flow cytometric analysis and polymerase chain reaction technique. RESULTS: The volume of gamma delta T cells in transitional mucosal lymphocytes (TML) were significantly higher than that in tumor infiltrating lymphocytes (TIL), and significantly lower than that in normal intestinal epithelial lymphocytes (IEL) (P < 0.05). The gamma delta T cell receptors delta chain V region (gamma delta-TCR Vdelta1-Vdelta6) gene rearrangement was all expressed in TIL, TML and IEL; but the Vdelta 6 gene expression in both TML and TIL were higher than that in IEL (P < 0.05). CONCLUSIONS: The decreased volume of gamma delta T cells in TML resulted in decreased local immune function and may be responsible for the local tumor recurrence after resection. The high expression of Vdelta 6 gene rearrangement in both TIL and TML suggests the skewing of gamma delta-TCR receptors and the abtitumor specificity of TIL and TML in local epithelium.

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

[Studies on immunization strategies for hepatitis B in different endemic areas of China].

OBJECTIVE: To compare the cost-benefit of immunization with hepatitis B (HB) vaccine in different endemic areas of HB and to explore the optimal strategy for it. METHODS: Cost-benefit analysis and comprehensive weighted score analysis (CWSA) were used to screen the optimal immunization strategy for low, medium and heavy endemic areas of HB. RESULTS: Significant economic benefit was obtained in Long-An County, Guangxi Zhuang Autonomous Region, Shanghai and Jinan, Shandong Province from HB immunization programs for infants. The greatest benefit cost ratio (BCR) was provided by the low-dose immunization strategy, which was 49.91, 54.53 and 37.68, respectively for heavy, medium and low endemic areas of HB. The maximal net benefit could be obtained by the high-dose immunization strategy with better immune protective efficacy. CWSA showed that the low-dose immunization strategy was the optimal one for HB immunization. CONCLUSION: It is suggested that the low-dose immunization strategy be implemented in undeveloped areas to obtain a greater BCR, and the high-dose one be implemented in more developed areas to obtain more net benefit and lower prevalence of hepatitis B surface antigen carriage.

China↗

PubMed1999

[Studies on changes in levels of hormone and expression of ob gene during induction of obesity in rats].

OBJECTIVE: To study the rules of changes in ob mRNA and its relation to hormone level in vivo in rats during their dynamic process to obesity induced by high-caloric fodder. METHODS: Level of ob mRNA in adipose tissues of rats was determined with dot-hybridization techniques, and levels of serum insulin and growth hormone were measured with radioimmunoassay. RESULTS: Level of ob mRNA in the fatty tissues and serum insulin level increased, but serum level of growth hormone decreased, with the increase in body weight of rats. CONCLUSION: Increase in expression of ob mRNA could be the result, but not the cause, of obesity. Changes in the levels of ob mRNA, serum insulin and growth hormone indicated that they could affect each other and could be regulated by common metabolic signals.

Adipose Tissue↗

PubMed1999

[Evaluation of DNA recombinant chitinase fusion protein antigens in serological diagnosis for filariasis].

OBJECTIVE: To evaluate DNA-recombinant chitinase fusion protein antigen in serodiagnosis for Bancroft's filariasis in jirds rats with microfilaremia and normal jirds rats with ELISA, and its prospect in the market to be spread. METHODS: Oligonucleotide was synthesized with filaria monoclonal antibody (Mf(1))-recognized microfilaria chitinase fusion protein and basic primer recognized by original clonal nucleosides, and amplified with polymerase chain reaction (PCR). PCR products were expressed in Pmal-c vector and purified by affinity chromatography. Experimental animals were inoculated with chitinase fusion protein antigen and infected with larval stage filaria Brugia malayi, respectively. Functional protein molecule of chitinase antigen was analyzed with SDS-PAGE and western blot. Serum level of specific antibody to chitinase antigen was determined by ELISA, and compared with that to microfilaria xt antigen (Mf-xt). RESULTS: Specific function protein molecule of the above-mentioned chitinase antigen has been identified as 69,000. Serum antibody against chitinase antigen was 100% positive for jirds and patients with microfilaremia, but, that against Mf-xt only 80% positive. Serum antibody against chitinase antigen was negative for all normal jirds and normal persons, but that against Mf-xt had 5% false positive in normal serum. For those with microfilaremia from non-filariasis-prevalent areas, false sero-positivity was 5% and 20% with chitinase antigen and Mf-xt, respectively. CONCLUSION: ELISA with DNA recombinant fusion protein antigen is a sensitive and specific method in serological diagnosis and surveillance for filariasis, with simple, easy and convenient manipulation. It can be used in field serologic surveillance and diagnosis for filariasis during the late phase in control of filariasis and can be spread in good prospects.

Animals↗

PubMed1999

[Significance of telomerase activity detection by fine-needle aspiration in patients with breast cancer].

OBJECTIVE: To study the telomerase activity in samples of breast fine-needle-aspiration specimens and to investigate its potential clinical implications. METHODS: Ninety nine fine-needle aspiration specimens from 83 patients with breast cancers, 12 with benign lesions and 4 with breast inflammation, were studied for the presence of telomerase activity by a PCR-based telomere repeat amplification protocol (PCR-TRAP). RESULTS: Among 83 fine-needle aspiration specimens from patients with breast cancer, telomerase activity was detected in 61 of 69 cytologic-positive specimens, 5 of 7 cytologic-suspicious specimens and 4 of 7 cytologic-negative specimens. Sensitivity of telomerase activity detection was 84.3% (70/83); the coincidence rate between telomerase detection and cytologic confirmation was 77.1% (64/83). Of 12 specimens from patients with benign breast lesions, 4 were positive for telomerase activity, but 4 specimens from patients with breast inflammation were all negative. The Combined use of cytological and telomerase detection can improve the detection rates from 83.1% (69/83) to 93.9% (78/83). CONCLUSION: Detection of telomerase in breast tissue samples by fine-needle aspiration is a sensitive and specific method, which implies that it would be helpful in preoperative cytological diagnosis of breast cancer.

Biopsy, Needle↗

PubMed1999

[Cloning of a new cDNA: responded to all-trans retinoic acid in HL-60 cell differentiation].

In this paper a new type of cDNA fragment named as W-1 gene was first cloned and sequenced from ATRA induced HL-60 cells by using differential display PCR (DD-PCR) and DNA sequencing techniques. These differentially expressing products of the gene responding to ATRA were further confirmed by Northern blotting analysis. The results showed that the expressing level of this gene induced by ATRA (10(-6) mol.L-1) for 16 hrs was much higher than that in the control HL-60 cells, but its expression in HL-60 was reduced to an unestimable level after induction of ATRA (10(-6) mol.L-1) for 24 hrs. It suggests that ATRA may increase the expression of W-1 gene during the early stage of HL-60 cell differentiation. The exact mechanism of action is being studied further.

Antineoplastic Agents↗

PubMed1999

[Studies on chemical constituents of Euphorbia ebracteolata Ilayata].

OBJECTIVE: To search for the effective anti-epilepsiy components from the Chinese folk drug Langdu, the root of Euphorbia ebracteolata. METHOD: Chromatography and spectroscopic analysis were used to isolate and elucidate the chemical constituents in the plant. RESULT: Four compounds, namely 10-nonacosanol, 24-methylenecycloartanol, stigmasterol and dacosterol have been isolated from the precipitate of the plant's methanol extract. CONCLUSION: 10-nonacosarnol and 24-methylenecycloartanol were obtained from the root of E. ebracteolate for the first time.

Euphorbia↗

PubMed1999

[Determination of nitrite in serum and tissue by oscillopolarography].

A method for determining nitrite in serum and placenta tissue by oscillopolaropgraphy is reported in this paper. Nitrite in 0.10 ml of serum or placenta homogenate reacts with sulfanilmide and N-1 (1-Naphthyl)-ethylendiamindihydrochloride in diluted hydrochloric acid medium to form an azo compound which can produce a sensitive reductive polarographic wave in ammonium alkaline medium. The wave height is directly proportional to the nitrite content, the method has a detection limit of 0.56 microgram/L (corresponding to the nitrite content of 0.61 mumol/L in serum or 0.22 microgram/g), RSD, of 6.1%-7.8% and recoveries of 92.0%-108.0% (mean value 100.6%). The method is sensitive, simple and can determine the nitrite directly without removal of the proteins in the samples.

Humans↗

PubMed1999

[Determination of flavonoids in pollen typhae(Puhuang) by HPCE and HPLC].

OBJECTIVE: To determine two flavonoids isorhamnetin-3-O-neohesperidoside(I) and typheneoside(II) in Pollen Typhae by HPCE and HPLC. METHOD: HPCE conditions: buffer = 0.02 mol.L-1 borate, 0.05 mol.L-1 SDS and 10% acetonitrile; V = 20 kV; T = 30 degrees C; lambda = 270 nm; sample size = 30 kPa.s, HPLC conditions: C18 lumn, acetonitrile-water (15:85) as mobile phase detection wavelength at 254 nm. RESULT: The contents of flavonoids I and II in five different Typha species and eighteen commercial samples of traditional Chinese drug Puhuang were between 0.1%-0.6%. CONCLUSION: These two methods are rapid, simple, accurate and can be used for the quality control of this traditional Chinese drug.

Chromatography, High Pressure Liquid↗

PubMed1999

[Study on the pharmacokinetics of the liver targeted mitoxantrone polylactic acid extended-release nanoparticles in rabbits].

HPLC was used to analyse the drug concentrations in blood. The 3p87 (practical pharmacokinetic program-version) was used to calculate the parameters of DHAQ-PLA-NP lyophilization injection and DHAQ injection through i.v. administration in rabbit blood. The concentration-time curves of the two kinds of preparations were in keeping with the three-compartment model. The drug concentrations were calculated according to the selecting pharmaceutical model and parameters. The calculated drug concentrations agreed well with the observed. The lyophilization injection sustained the eliminating process in vivo.

Animals↗