Search PubMed⌕ Search

Biomedical subjects

Y Yang

Publications and source records attributed to Y Yang.

At least 487 records · Page 27Linked to original sources
PubMed2000

[The construction of PQE-ARL-1 recombinant expression plasmid and the preparation and purification of ARL-1 protein].

OBJECTIVE: To further understand the function and biological activity of aldose reductase like-1 (ARL-1), and to provide the basis for the preparation of the specific antibody against ARL-1. METHODS: The ARL-1 cDNA was cloned into procaryotic expression vector PQE-30 and the recombinant ARL-1 expressed in E.coli M(15); then Ni(+)-NTA agarose columns were used to purify the ARL-1 protein. RESULTS: With the digestion of the enzymes, we identified that the ARL-1 gene was inserted into the procaryotic expression vector PQE-30. The expression products of PQE-ARL-1 (human recombinant ARL-1) showed a single protein band on SDS-PAGE. The molecular weight of ARL-1 was approximately 37.7 x 10(3) and the expression level was about 25% of the total bacterial protein. The concentration of ARL-1 protein was about 100mg/L. CONCLUSION: The construction of the recombinant plasmid PQE-ARL-1 and the preparation of the protein ARL-1 have laid a solid foundation for further studying the function of ARL-1 and preparing the specific antibody against ARL-1.

Aldehyde Reductase↗
PubMed2000

[An analysis of the clinical and laboratory data of 53 cases of non-Hodgkin's lymphoma].

OBJECTIVE: To analyse the influence of factors on the prognoses of non-Hodgkin's lymphoma (NHL) and the clinical usage of IgH and T cell receptor(TCR) gene rearrangement for NHL typing. METHODS: Immunological phenotyping was carried out by SABC, and IgH(FR2A, FR3A) and TCR(beta, gamma) detection by PCR. RESULTS: The age curve of NHL was increased parallel with the patient's age increasing, hazard ratio was increased 1.039n annually. The incidence of B cell NHL(B-NHL) was 66.7%, T cell NHL(T-NHL) was 31.1%, low grade NHL was 56%, middle and high grade NHL were 44%. The positivity of IgH and TCR gene rearrangement in NHL patients were 75% by PCR detection, T and B classification was same as phenotyping. The 3 and 5 years survival ratio: HD were 83.3% and 62.5%, stage I-II of NHL were 88.9% and 66.7%, stage III-IV of NHL were 39.9% and 33.3%, Low grade NHL were 65.1% and 48.8%, middle and high grade NHL were 47.6% and 39.6%. The survival time of APBSCT group was longer than that of the conventional therapy group. CONCLUSION: Age, T,B classification, grading and staging are the important factors which affect on NHL prognoses. APBCST can improve NHL prognoses, especially for those of stage III-IV patients. Molecular biological methods can help T/B classification when it couldn't be confirmed by phenotyping.

Adult↗
PubMed2000

[Improvement of pulse waveform detection with autoregressive model in blood oxygen saturation measurement].

Blood oxygen saturation is an important physiological parameter of human body. The accurate measurement of it is important to both physiological research and medical application. Dual-wavelength method is widely adopted in nonivasive detection of blood oxygen saturation. In this method, the calculation of blood oxygen saturation is based on the identification of pulse waveform and the extraction of peak characteristic values. But the pulse waveform obtained from this method merely has distinctive features such as the QRS complexes in ECG, so the ratio of correct detection of pulse waveform is always low. An autoregressive model of heart-beat intervals is developed. The output of the differential method is compared with that of the AR model so as to distinguish the false or missing detection. The ratio of correct detection is improved by the use of this method.

Models, Theoretical↗
PubMed2000

[The effect of coxsackie virus B3 on intracellular calcium homeostasis in rat cardiomyocytes].

OBJECTIVE: To investigate the effect of coxsackievirus B3 (CVB3) on intracellular calcium, L type voltage dependent calcium channel (VDCC) and Na+/Ca2+ exchange (NCE) in adult rat cardiomyocytes. METHODS: Rat hearts were perfused with collagenase to gain single cardiomyocyte. The intracellular free calcium concentration of the cardiomyocytes were detected by laser confocal microscopy with calcium indicator, Fluo3-acetoxymethyl ester; and the currents of VDCC, Na+ and NCE were recorded by patch clamp techniques. RESULTS: The free intracellular calcium concentration increased from (51 +/- 43) nmo1/L in normal cardiomyocytes to (339 +/- 208) nmo1/L in CVB3 infected cardiomyocytes. The VDCC current increased from (4.13 +/- 0.75) pA/pF to (4.9 +/- 1.4) pA/pF after CVB3 infection, and the inward NEC current decreased from (-0.46 +/- 0.21) pA/pF to (-0.28 +/- 0.16) pA/pF; besides, the reverse potential of NCE was shifted from (29.4 +/- 7.0) mV to (41 +/- 14) mV with CVB3 infection. CONCLUSIONS: The increase of L type VDCC current and decrease of inward NCE current with shift of NCE reverse potential may partly attribute to intracellular free calcium accumulation; also, it may be the cause of cell damage and the occurrence of abnormal electric activities induced by CVB3 infection.

Animals↗
PubMed2000

Effects of tripcholorolide on inflammatory reaction of mouse alveolar macrophages in vitro.

AIM: To observe the effects of tripcholorolide (T4) on inflammatory reaction of mouse alveolar macrophages. METHODS: RT-PCR was used to investigate tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), IL-6, IL-10, and inducible nitric-oxide synthase (iNOS) mRNA expression in alveolar macrophages after LPS 10 mg/L and T4 500 micrograms/L treatment. ELISA was used to detect TNF alpha, IL-1 beta, IL-6, and IL-10 protein expression. Nitrite was measured by Griess reaction. RESULTS: TNF alpha, IL-1 beta, IL-6, IL-10, and nitrite increased in supernatants, when alveolar macrophages were stimulated by LPS 10 mg/L at 24 h. Both T4 500 micrograms/L and dexamethasone 100 mumol/L had inhibitory effects on the production of TNF alpha, IL-1 beta, IL-6, IL-10, and nitric oxide. The mRNA expression of TNF alpha, IL-6, IL-10, and iNOS increased at 5 h after LPS stimulation which was decreased on addition of T4 500 micrograms/L or dexamethasone 100 mumol/L. T4 had no effect on stability of LPS-induced mRNA expression in TNF alpha, IL-6, and IL-10. CONCLUSION: T4 had inhibitory effects on the expression of proinflammatory and antiinflammatory mediators.

Animals↗
PubMed2000

[Lifetable of cotton bollworm under different control condition].

The lifetables of 3rd and 4th generation of cotton bollworm Helicoverpa armigera Hubner were established by action factors under four different control conditions. The results showed that under natural control, the egg parasitic rates of 3rd and 4th cotton bollworm were 4.39% and 1.19%, the predatory rates were 21.11% and 15.80%, and the larvae parasitic rates were 19.34% and 16.20% respectively. The indexes of population trend were only 0.0032 and 0.0014 respectively, after using selective pesticides IKI and Bt to control cotton bollworm. Though the index of population trend decreased to 48.66% and 61.67% after contantly praying chemical pesticides, the number of predators also decreased to 23.48% and 41.26% respectively. Transgenic Bt cotton could inhibit the population increase of cotton bollworm, but had no effect on predators. The parasitic rates of 3rd and 4th cotton bollworm on Transgenic Bt cotton were 51.14% and 0% respectively, as compared to control.

Animals↗
PubMed2000

[Effect of Nerium indicum on killing Oncomelania hupensis].

A laboratory experiment at 20 +/- 5 degrees C shows that the water extract of fresh Nerium indicum had an obvious effect on killing Oncomelania hupensis. Treated with 0.1% water extract for four days, the mortality of O. hupensis was up to 100%. The effect of different tissues of N. indicum on O. hupensis was in order of stem phloem > leaf > root phloem > flower. The effect of N. indicum on O. hupensis was about ten times higher than that of Pterocarya stenoptera and Rumex japonicus, and was equal to that of 1 x 10(-3) mg.L-1 niclosamidum.

Animals↗
PubMed2000

[Age structure of tillers of Hordeum brevisulatum clone in Songnen plain of China].

The tillers of Hordeum brevisulatum clone have a significantly expanding age structure, which includes three age classes. The 1st age class tillers are absolutely dominant in the reproductive growth of the clone. The older the tillers, the smaller the rate of quantitative increase, and the less the accumulative nutrients are. The quantity and biomass of the 1st and 2nd age classes increase with the size and the tiller number of the clone, while the 3rd age class tillers are positively linearly interrelated to the total tillers of the clone. The mean weight per tiller decreases with the age class increased. The mean weight per reproductive tiller is relatively constant among three age classes, and that of the 1st tillers of clone has a negative respondence to the density of tiller. The age structure of the potential population of clone is also of an obviously expanding type. The buds on the vegetative tillers are always more than those on the reproductive tillers. The buds on the vegetative or reproductive tillers of every age class are all positively interrelated to the size and the total tillers of clone.

Biomass↗
PubMed2000

[Influence of estrogen on the epithelial ovarian cancer cell lines in vitro].

OBJECTIVE: To study the effect of 17-beta estradiol on the growth of the epithelial ovarian carcinoma cell lines in vitro. METHODS: The proliferative capacity of the ovarian carcinoma cell lines CAOV3 and OVCAR3 in the culture medium with 17-beta estradiol was evaluated by the means of the mircoculture tetrazolium assay (MTT) and cell kinetics was analyzed by flow cytometry (FCM). The expression of estrogen receptor (ER) of the two cell lines was examined by the immunohistochemical staining. RESULTS: The growth of both two epithelial ovarian cancer cell lines was slightly inhibited by 17-beta estradiol (0.25-5.00 nmol/L), and the inhibitive rate was 6.3%-36.0%. FCM showed that the kinetics of the two cell lines were obviously changed. Comparing with the kinetics of CAOV3 without estradiol, the cell rate of Stage G0/G1 of CAOV3 with estradiol decreased from 55.0% to 19.0%-30.0%, cell rate of Stage S increased from 30.0% to 52.0%, cell rate of Stage G2/M increased from 14.0% to 17.0%-28.0%; In OVCAR3, cell rate of Stage C2/M decreased from 37% to 22.0%-30.0%, cell rate of Stage S increased from 31.0% to 38.0%-51.0%, cell rate of Stage C0/G1 did not changed much (cell rate without estradiol was 32.0%, while cell rate with estradiol 29.0%-31.0%). Estrogen receptors of the two cell lines were positive and not changed after cultured in the medium with 17-beta estradiol. CONCLUSION: The proliferate capacity of the two epithelial ovarian cancer cell lines CAOV3 and OVCAR3 can be inhibited by the estrogen (0.25-5.00 nmol/L), possibly through the change of the tumor cell kinetics.

Cell Cycle↗
PubMed2000

The prevalence of lactase deficiency and lactose intolerance in Chinese children of different ages.

OBJECTIVE: To determine lactose metabolism and lactase activity in Chinese children of different ages, prevalence of lactase deficiency (LD), and lactose intolerance (LI). METHODS: All 1168 healthy subjects between 3 and 13 years were recruited from schools in four large cities in China. They were screened by a 25 g lactose tolerance test. Some subjects were challenged with 50 g milk powder on different days. Both indicators, the expiratory H2 concentration and intolerance symptoms, were analyzed. RESULTS: LD occurred in 38.5% of children in the 3-5 year age group, and 87% of the 7-8 year and 11-13 year old groups. The age of occurrence for LD may be at 7-8 years among Chinese children. The prevalence of LI among Chinese children was 12.2% at age 3-5 years, 33.1% at age 7-8 years, and 30.5% at age 11-13 years, respectively. CONCLUSION: The results demonstrate that LD is very common in Chinese children from these four cities. LD and LI have a dose dependent response: lactose absorption and symptoms are based on lactase activity. The relationship between breast feeding history (or the history of cow milk intake) and lactase activity among Chinese children has not been established.

Adolescent↗
PubMed2000

[Changes of glutamate and gamma-aminobutyric acid contents in brain tissue of brain edema and effects of baicalin on them in rats].

OBJECTIVE: To observe the changes of glutamates (Glu) and gamma-aminobutyric acid (GABA) contents in brain tissue of infectious brain edema, and effects of baicalin on them in rats. METHODS: The high performance liquid chromatography (HPLC) was used to determine the Glu and GABA contents in homogenized brain tissue after baicalin was injected intraperitoneally on infectious brain edema induced by pertussis bacilli in rats. RESULTS: Glu contents of homogenized brain tissue in blank control group (C), normal saline group (NS), pertussis bacilli group (PB) and baicalin group (BC) had no significant difference (P > 0.05). The concentration of GABA was more significantly increased in the BC group (4.06 +/- 0.52) than that in the PB group (2.71 +/- 0.29) (P < 0.05). Water content of brain was reduced in the BC group (79.8 +/- 0.4) as compared with the PB group (82.2 +/- 0.3)(P < 0.01). CONCLUSION: Baicalin has a protective effect against the pertussis bacilli-induced brain edema in rats, and protective effect was correlated to the increased content of GABA in the brain tissue in rats.

Animals↗
PubMed2000

[The relationship between clinical types of postinfarction angina and stenosis of ischemia-related artery].

OBJECTIVE: To approach the pathogenesis of postinfarction angina and set up its treatment guidelines. METHODS: 67 patients with postinfarction angina undergoing coronary angiography during the hospitalization were studied. RESULTS: (1) According to the clinical classification of angina pectoris, spontaneous angina is the most common type (43.9%); mixed angina is second (25.7%), effort angina and variant angina are relatively low frequency (16.7% & 13.6%). (2) Stenosis >or= 90% in the ischemia-related artery accounted for the anginal symptoms constituted 100%, 82.8%, 72.7% and 44.4% of the cases with mixed angina, spontaneous angina, effort angina and variant angina respectively. (3) Postinfarction angina caused by non infarction-related artery was relatively less frequent (8.9%). CONCLUSIONS: Severe residual stenosis of infarction-related artery is the main pathologic factor on the pathogenesis of postinfarction angina, so early interventional therapy or bypass surgery should be taken.

Adult↗
PubMed2000

[Cytokine-induced release of plasminogen activator inhibitor-1 by human pleural mesothelial cells].

OBJECTIVE: To investigate the effects of inflammatory cytokines on the production of plasminogen activator inhibitor-1 (PAI-1) by human pleural mesothelial cells (HPMC). METHODS: Six primary cultures of HPMC isolated from patients with exudative pleural effusion were incubated in DMEM/F12 medium to examine the effect of interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNFalpha) or transforming growth factor-beta1 (TGF-beta1) on the fibrinolytic properties of HPMC in vitro. The purity of the cell population was assessed by morphologic, ultrastructural and immunohistochemical characteristics. PAI-1 activity in the conditioned media of third passage HPMC was detected using chromogenic substrate method. RESULTS: As compared with the controls, PAI-1 activity in the conditioned media of HPMC increased significantly by stimulation with IL-1beta, TNFalpha or TGF-beta1 for 24 hours at the level of 0.20 microg/L (IL-1beta: q = 3.38, P < 0.05; TNFalpha: q = 4.41, P < 0.05; TGF-beta1: q = 22.03, P < 0.01), 2.00 microg/L (IL-1beta: q = 12.28, P < 0.01; TNFalpha: q = 16.60, P < 0.01; TGF-beta1: q = 19.23, P < 0.01) and 20.00 microg/L(IL-1beta: q = 24.30, P < 0.01; TNFalpha: q = 25.00, P < 0.01; TGF-beta1: q = 49.30, P < 0.01). Furthermore, HPMC responses to TGF-beta1 were significantly greater than those to IL-1beta or TNFalpha. CONCLUSION: These results suggest that inflammatory cytokines might mediate the release of PAI-1 by HPMC in vivo, affect the deposition of fibrin within the pleural cavity and favor fibrogenesis.

Adult↗
PubMed2000

[Determination of S-100 beta protein in cerebrospinal fluid of patients with metastatic carcinoma to central nervous system].

OBJECTIVE: To investigate the concentration of S-100 beta protein in cerebrospinal fluid (CSF) for 25 patients with metastatic carcinoma to central nervous system (CNS), and to evaluate its clinical value. METHODS: S-100 beta protein of CSF was measured by ELISA for 25 patients with metastatic carcinoma to CNS and 20 patients without any CNS disease (control group). The patients were divided into three categories according to severity of disease: severe group, moderate group and mild group. Meanwhile, CSF cytology was also detected. RESULTS: The level of S-100 beta protein of all patients was higher than that of control group (P < 0.01), and severe group > moderate group (P < 0.01) > mild group (P < 0.01). The percentage of CSF lymphocyte in severe group was lower than that of mild group and control group (P < 0.05 and P < 0.01). CONCLUSIONS: CSF S-100 beta protein level of patients with metastatic carcinoma may be related to the severity of their brain insult.

Adolescent↗
PubMed2000

[Transoral microsurgical treatment of craniocervical malformation].

OBJECTIVE: To discuss transoral microcervical treatment of 16 patients with craniocervical malformation. METHODS: Perioperative treatment including antibiotics, tracheotomy, intravenous nutrition was used in 16 patients. RESULTS: Eight patients had basilar impressions, 3 chronic atlantoaxial dislocation and 2 odontoid fracture, 2 lower clivus chordoma, and 1 granuloma in the ventral part of the medulla oblongata. Three patients received bone graft. Follow-up for 6 - 36 months showed that 14 patients resumed normal life but 1 died. CONCLUSIONS: Pre-craniocervical malformation can be treated by transoral approach microsurgically. Understanding microanatomy of this approach can reduce postoperative morbidity and complications. Perioperative treatment can prevent incision infection. Prevention of intraoperative CSF leakage must be emphasized.Bone graft can make craniocervical spine stable.

Adolescent↗
PubMed2000

[Tracheal transplantation].

OBJECTIVE: To treat long tracheal cancer by tracheal transplantation. METHODS: In March 17, 1999, a patient received a total laryngeal resection and a resection of 8 cm upper and middle trachea, which was replaced by a 6 cm long trachea of another donor. The donor trachea was dipped first in preservation liquid A for sterilization for 24 hours, then in preservation liquid B for over 48 hours for destructing MHC. Pedunculated greater omentum and pedunculated greater pectoral musculus supplied the blood for the donor trachea. One side of the donor was anastomosed with the lower trachea, and the other with the neck skin. RESULTS: The patient survived 300 days after operation. The auto tracheal membrane covered the donor surface; auto- and xeno trachea was well anastomose. The new trachea grew very well. CONCLUSION: Trachea transplantation is possible the best method to treat long tracheal disease if the transplantable trachea is less 5 cm.

Aged↗