Study of HIV antibody screening for blood donors by a pooling-serum method.
Explore the source record for details and available documents.
Blood Donors↗
Biomedical subjects
Y Ji
Publications and source records attributed to Y Ji.
[Impaired calcium uptake by cardiac sarcoplasmic reticulum and its underlying mechanism during rat septic shock].
The underlying mechanism of Ca2+ uptake function of cardiac sarcoplasmic reticulum (SR) was investigated in the rat septic shock model produced by cecal ligation and puncture (CLP). The results are as follows. During the early phase of sepsis, the initial rate of ATP-dependent Ca2+ uptake by SR was decreased, while both the capacity of Ca2+ uptake and the activity of Ca(2+)-ATPase were unaffected. In the late sepsis, the impairment in SR function was even greater as the initial rate and the capacity of Ca2+ uptake by SR were significantly decreased, and this was paralleled by a reduction in Ca(2+)-ATPase activity. Although Ca2+ affinity (Km value) to calcium pump and the A0.5 values for Mg2+ and ATP activation on the Ca2+ uptake rate were unchanged, during sepsis the phosphorylation of SR vesicles by adding of catalytic subunit of the cAMP-dependent protein kinase (PKA), calmodulin, or the fragment of PKC into Ca2+ uptake buffer, failed to stimulate Ca2+ uptake activities of SR isolated from early or late septic rats. These data suggest that depression of cardiac SR function is aggravated as sepsis develops, the impairment of SR Ca2+ uptake is possibly based on a mechanism of defective phosphorylation of SR rather than the ionic and energic regulatory actions of Ca2+, Mg2+, ATP on cardiac SR.
Animals↗
[Altered ryanodine receptor of rat cardiac sarcoplasmic reticulum and its underlying mechanism during septic shock].
The present study was undertaken to observe the changes of Ryanodine receptor of cardiac junctional sarcoplasmic reticulum (SR) in relation to membrane lipid microenvironment alteration during septic shock. The results showed that the Bmax for 3H-ryanodine binding to cardiac junctional SR was decreased by 41.3% (3.9 +/- 0.1 vs. sham 6.6 +/- 0.7 pmol/mg, P < 0.01) while the Kd value was unaffected during late septic shock (CLP 18 h). Ca2+ activated 3H-ryanodine binding significantly and reached a saturation value when Ca2+ concentration was 5 x 10(-5) mol/L, while the S0.5 and the Hill coefficient values remained unchanged during septic shock. Caffeine, ATP, and AMP-PCP activated while Mg2+, ruthenium red inhibited 3H-ryanodine binding in both groups but the A0.5 (concentration requires for half maximum activation) and the IC50 (concentration requires for half-maximum inhibition) for the above mentioned activators and inhibitors, were respectively unaffected during septic shock. Digestion of cardiac SR isolated from control rats with phospholipase A2 inhibited 3H-ryanodine binding, which could be dramatically recovered by the incorporation of phosphatidylcholine (PC), or phosphatidylserine (PS), or phosphatidylethanolamine (PE) into the isolated cardiac SR. Incorporation of above phospolipids into SR isolated from septic rats reversed shock-induced inhibition of 3H-ryanodine binding. It is concluded that the mechanism responsible for the inhibition of 3H-ryanodine binding of junctional SR during septic shock may be related to modification of membrane lipid microenvironment in response to PLA2 overactivation during septic shock.
Animals↗
An extensive subfrontal approach to the lesions involving the skull base.
A modification of the transbasal approach of Dorome called extensive subfrontal approach and the surgical results with this approach in 22 cases are presented. Bilateral frontal craniotomies incorporated with the removal of orbital ridges and part of the orbital roofs were fashioned en bloc. It may give rise to good exposure of the midline lesions of the anterior, middle and posterior skull base, minimizing the need for the retraction of frontal lobes. There was no surgical mortality in this series of cases. Of the 20 cases with tumors, total resections were achieved in 11 cases, subtotal or large resections in 4 cases and partial resection in one case. Two patients with spontaneous rhinorrhea were successively treated surgically. 21 patients had a follow-up with a time ranging from 1-11 years (a mean of 3 years). 15 patients resumed their jobs with no evidence of recurrence of the original disease, and 5 patients able to live self-care. One patient with an olfactory neuroblastoma died 3 years after the operation owing to relapse of the tumor.
Adolescent↗
Purification and partial amino acid sequences of a new presynaptic toxin and a cytotoxin from venom of pit veper Agkistrodon blomhoffii brevicaudus.
The technique of the reverse-phase performance liquid chromatography (RP-HPLC) was employed to separate and purify the toxic proteins from the venom of Agkistrodon blomhoffii brevicaudus collected in China. 3 toxic proteins marked as AgTx-1, AgTx-2 and AgTx-3 consisting of about 122 amino acid residues were screened. The toxicities (LD50) of the AgTx-1, AgTx-2 and AgTx-3 were 0.075, 0.51 and 6.6 mg per kg weight of mice respectively. Toxicological experiment in the chick biventer cervicis nerve-muscle preparation showed that the acetylcholine (Ach) sensitivity of the preparation was unchanged after the total failure of the indirect contraction caused by AgTx-1 and AgTx-2, suggesting that they were presynaptic blockers, namely beta-type of snake toxins. However, the amplitude of indirect contraction of the preparation was gradually reduced due to its incomplete relaxation caused by AgTx-3, indicating that it should belong to the category of cytotoxins. The partial amino acid sequences of 3 toxins have been established. It was found in ref. [1] that the sequences of the first 32 N-terminal amino acid residues of AgTx-1 and AgTx-2, as well as beta-agkistrodotoxin (beta-AgTx) reported previously were identical (the residue at the position 30 of beta-AgTx should be Trp). In view of the similarity in toxicities, and the amounts in the venom and other properties, it was concluded that AgTx-1 should be beta-AgTx and consequently was renamed beta 1-AgTx. AgTx-2 should be the isoform of beta 1-AgTx, and correspondingly named beta 2-AgTx.
Agkistrodon↗
[Effects of taurine and enalapril on blood pressure, platelet aggregation and the regression of left ventricular hypertrophy in two-kidney-one-clip renovascular hypertensive rats].
In two-kidney-one-clip (2k-1c) renovascular hypertensive rats, the blood pressure, left ventricular weight/body weight (LVW/BW) ratio and blood platelet aggregation were increased significantly. Enalapril (Ena) 6 mg . kg-1 . d-1 ig 9 wk and Taurine 30 mg . kg-1 . d-1 ig 9 wk can not only decrease the high blood pressure, LVW/BW ratio, but also the blood platelet aggregation induced by ADP or thrombin, though still different from that of the normal group. When the 2k-1c renovascular hypertensive rats were treated with both Ena and Tau, the blood pressure and blood platelet aggregation were decreased to the same as that of the normal group, and the LVW/BW ratio was also lowered markedly, though still higher than that of the normal group. These results show that both Ena and Tau can reverse the left ventricular hypertrophy, decrease the blood pressure and suppress the blood platelet aggregation in 2k-1c renovascular hypertensive rats. When treated with both drugs, the effects can be improved. It suggests that the two drugs can enhance the effects when used together, and that they may be two good agents for treatment of hypertension.
Animals↗
Toxicity of photodynamic therapy with photofrin in the normal rat brain.
The widespread acceptance of photodynamic therapy (PDT), a potential adjuvant brain tumor therapy under clinical evaluation since 1980, has been partially restrained by its potential toxicity toward normal brain tissue. This study examined PDT-produced injury of normal rat brain as a function of photosensitizer dose. Brain injury was characterized by correlating measurements of the area of cerebral edema using T2-weighted magnetic resonance images, measurement of brain water content at the lesion site, microscopic examination of histological sections through the PDT lesion, and by evaluation of the area of blood brain barrier (BBB) disruption using computerized morphometric analysis of the region of Evans blue (EB) dye-labelled albumin extravasation. Monochromatic red light (630 nm) was delivered intracerebrally using a 5-mm-long cylindrical, diffusion-tip optical fiber at a constant energy dose of 15 joules. A Photofrin dose of 2 mg/kg of body weight produced a transient breakdown in the blood brain barrier around the site of the implanted optical fiber demonstrated by magnetic resonance imaging (MRI), extravasation of EB dye and pallor on hematoxylin and eosin-stained microscopic tissue sections. A much larger area of BBB disruption was seen at a dose of 4 mg/kg of Photofrin, and this drug dose resulted in significant permanent brain injury. In this model, a Photofrin dose of 4 mg/kg body weight is not tolerated by the normal brain.
Animals↗
[Effect of the changes of amino acids on both signal peptide C-terminal and mature protein N-terminal region to the secretion of alpha-amylase in B. subtilis].
By site-directed mutagenesis, G and C have taken the place of T and G at nucleotide sequence 287 and 291 of B. licheniformis alpha-amylase gene to generate pAm-y413B and the N-terminal sequence of mature protein have been changed from 7Leu 8Met to 7Arg8Ile. By the insertion of polylinker into the C-terminal of the signal sequence of alpha-amylase gene of pAmy413, the signal peptide of alpha-amylase produced by pAmy413L is 13 amino acids more than the pAmy413 (which is 29 amino acids long) and also, a new recognition cleavage sequence for signal peptidase I (Ala-Gln-Ala decreases Ser) is created; The secondary structure of the signal peptide has been analyzed by computer programs. The alpha-amylase relative activity of the two mutant strains is 3% and 36% of pAmy413, respectively. The molecular weight of extracellular alpha-amylase is the same as pAmy413. Terminal analysis shows that the N-terminal amino acid of mature protein is Ala, not Ser, and suggests that SPase I prefers to cleavage at the wild type recognition site (Ala-Ala-Ala decreases Ala). Therefore, all of the above results show that the secretion of alpha-amylase in B. subtilis is in accordance with the co-translational transportation model.
Amino Acid Sequence↗
[Drug antagonism of TNF induced proliferation of bovine cerebromicrovascular smooth muscle cells].
Effects of tumor necrosis factor (TNF) on the proliferation of bovine cerebromicrovascular smooth muscle cells (BCSMC) were investigated. At concentrations from 50 to 5000 U.ml-1, TNF was shown to induce proliferation of cultured BCSMC in a dose-dependent manner. After 24 h incubation of the cells, TNF significantly stimulated the proliferation of BCSMC and reached maximal effects after 48 h incubation, then the effects slightly decreased. At concentrations from 10(-6) to 10(-4) mol.L-1, both imperatorin (Imp) and iso-imperatorin (Isi) were found to antagonize the TNF induced proliferation of BCSMC. Their maximal inhibitory effects were 42.2 and 36.1% at 10(-4) mol.L-1 respectively. 6-(alpha,alpha-diphenylacetylpiperazinly) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone (DMDP) and 6-(alpha-phenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3(2H)-pyridazinone (PMDP) were also found to possess similar effect at lower concentration (10(-6) mol.L-1), but no significant effect was observed when the drug concentration was higher.
Animals↗
Human myeloperoxidase gene cDNA cloning and expression in acute leukemia.
In this study, the light chain and a part of the heavy chain cDNA segment of human myeloperoxidase (MPO) were cloned with PCR and other DNA recombination techniques from HL-60 cell. The size of the cloned cDNA was 769 bp. A segment about 600bp of the cDNA was analyzed by DNA sequencing and showed no difference from the human MPO cDNA sequences published before. The MPO cDNA was used as a probe to study the MPO gene expression in leukemic cells. The Northern blot analysis and slot blot analysis of RNA isolated from leukemic cell lines and blast cells of acute leukemia showed that MPO gene expression correlated with myeloid lineage and might be used as a marker for the subclassification of acute leukemia.
Acute Disease↗
[Effects of 6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone on rabbit platelet aggregation and TXB2, cAMP production].
6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone (DMDP) is a new synthetic pyridazinone derivative. This compound was shown to inhibit AA, ADP and PAF-induced rabbit platelet aggregation, and its IC50s were found to be 1.12 +/- 0.1, 4.19 +/- 0.5 and 2.97 +/- 0.1 mumol/L, respectively. At the concentration range of 1-500 mumol/L, the compound was found to depress TXB2 content and to increase cAMP levels in washed rabbit platelets in a dose-dependent manner. These might be the mechanisms of the compound on the inhibition of rabbit platelets.
Animals↗
Relation between polyporphyrin distribution and blood brain barrier changes in the rat glioma model.
Photofrin (a polyporphyrin mixture) distribution in a rat glioma model was studied in relation to changes in the blood brain barrier (BBB). At selected intervals after intraperitoneal injection of Photofrin, the concentration of polyporphyrins (PP) and Evans Blue Dye, an indicator of BBB permeability, were determined for tumor, brain adjacent to tumor (BAT), and normal brain tissue. Contrary to earlier reports of maximal accumulation at 4-24 hours, tumor levels of PP increased throughout the 96 hour measurement period. During the early stages of tumor development, PP uptake by tumor appeared to be less correlated to BBB disruption. We conclude that passive diffusion through an incompetent BBB does not completely explain PP accumulation in tumor tissue.
Animals↗
Interstitial photoradiation injury of normal brain.
The effect on normal brain of continuous interstitial laser irradiation at 630 nm through an implanted cylindrical-shape, diffusion-tipped optical fiber was studied in the rat. Brain water content in the laser irradiation area (LIA) and Evans blue (EB) dye content in selected areas of the brain were measured for different laser power outputs from 0 to 250 mW after 5 minutes of photoradiation. The degree and nature of tissue damage was examined histologically and correlated with the laser power level. There is significant brain damage, blood brain barrier (BBB) disruption, and brain edema in LIA for laser power outputs in excess of 100 mW from the diffusion tip (p less than 0.001). Brain edema in the LIA is strongly correlated with BBB disruption indicated by the presence of EB. Histologically, the cortical surface was more susceptible than deeper white matter regions to interstitial laser irradiation. Possible indirect mechanisms of brain injury from interstitial laser irradiation are discussed.
Animals↗
Improved survival from intracavitary photodynamic therapy of rat glioma.
The effectiveness of intratumoral photoradiation in photodynamic therapy (PDT) using a polyporphyrin photosensitizer was studied in the RT-2 rat glioma model. One week after intracerebral implantation of RT-2 cells, experimental rats received a single i.p. injection of 2 mg/kg of Photofrin. After administration of the photosensitizer (48 h), the tumors were partially resected and the exposed cavity was irradiated with 15 J of laser light at a wavelength of 630 nm. Further treatment with a large craniectomy significantly enhanced rat survival. Control rats which received no photosensitizer but were treated with surgery, alone or in combination with laser irradiation, succumbed from early tumor recurrence. Photodynamic therapy without decompressive surgery resulted in hemorrhagic infarction of residual tumor and adjacent brain with focal cerebral edema which resulted in cerebral herniation and early death. Our results indicate that photodynamic therapy is effective in treating residual brain tumor but at the expense of brain tissue surrounding the tumor. Unless relieved, intracranial pressure from photodynamic therapy-associated cerebral edema in this animal model resulted in shortened survival.
Animals↗
776 cases of pain treated with auriculopressure therapy.
Explore the source record for details and available documents.
Abdominal Pain↗
The establishment of rat-mouse hybridomas secreting anti-aflatoxin M1 antibodies and the properties of their monoclonal antibodies.
After a comparison of anti-AFM1-BSA antibody responses between rat and mouse, the spleen cells of rat with stronger responses were chosen as parent cells for fusing with mouse myeloma cells P3X63-Ag8.653. Through HAT medium selection, RIA screening and cloning, five well growing rat-mouse hybridoma clones were obtained that could secret anti-AFM1 antibodies stably. The results from ELISA and competitive binding RIA further proved that the 5 McAbs are direct against AFM1, with significant cross reaction to its derivative, AFB1. The average affinity constant of the 5 McAbs is 10(9)-10(11) l/M. It signifies that these monoclonals have potential application value for the construction of AF detection kit.
Aflatoxin M1↗
[Internalization of monoclonal antibodies against human hepatoma in the target cells].
The monoclonal antibodies against human hepatoma, HAb23, HAb18 and HAb8, were linked with 5 nm colloid gold. They were used to incubate with the target cells, QGY-7703 and SMMC-7721 human hepatoma cell lines, at 4 degree C for 1 hour. The incubated hepatoma cells were divided into 6 groups and then were put into 37 degree C water incubator for 0, 5, 10, 30, 60 and 120 minutes respectively. After washing, the target cells were fixed with Karnovsky's fixative and embedded in Epon 812. There were four intracellular routings for HAb 23, HAb18 and HAb8 to enter the QGY-7703 and SMMC-7721 hepatoma cells: (1) Coated pits coated: The colloid gold-antibodies which clustered in the specialised regions of the surface membrane were invaginated rapidly into the cells to form coated vesicles. (2) Enclosed invagination: One or two colloid gold-antibodies which were attached on the surface membrane were invaginated into the cell by endocytosis. (3) Microvilli involved routing: The microvilli which were adsorbed by the colloid gold-antibodies were broken and then were phagocytized by the cells. (4) Routing via glycocalyx-like material: The glycocalyx-like material which was clustered by the colloid gold-antibodies was invaginated during endocytosis.
Antibodies, Monoclonal↗
[Selection of methods for HIV screening of donors' sera and blood products].
Blood and blood products are very important agents of HIV transmission. In this paper, 11,251 samples from 10,422 donors' sera and 150 blood products were screened for anti-HIV by ELISA, PA, IF and WB. The results were all negative. The donors lived in the 10 municipalities and counties of Sichuan Province. We also performed a prospective investigation to learn if these four methods were suitable to different blood products. We found that positive or weak positive reactions of ten occurred when gamma-globulins were detected by IF and ELISA, but the results were negative when gamma-globulins were tested by PA and WB. As a screening assay for anti-HIV, PA is most suitable for gamma-globulin. WB assay is the optimal method for anti-HIV testing in terms of both specificity and sensitivity. However, because the necessary reagents are very expensive and the procedure is time-consuming, we suggest that the WB assay may be used as a confirmatory test for anti-HIV assay in countries and regions where its general use is cost-prohibitive.
Albumins↗