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Biomedical subjects

J Shi

Publications and source records attributed to J Shi.

At least 109 records · Page 6Linked to original sources
PubMed2001

[A quantitative pathological study on angiogenesis, vascular endothelial growth factor and inducible nitric oxide synthase in astrocytomas].

OBJECTIVE: To investigate whether the expression of vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) are associated with angiogenesis and malignancy of astrocytomas. METHODS: Immunohistochemistry, semiquantitation and image analysis were used to study the expression features of VEGF and iNOS in 61 cases of astrocytomas having follow-up data. Factor VIII related antigen (FVIII RAg) was also analysed in reflecting the epithelial cell amount and the microvessel density. RESULTS: Microvessels in astrocytomas could be divided into seven types. The positive reaction areas and IA values of FVIIIRAg expression in the endothelium were significantly increased with the increase of tumor grade (P < 0.001) and VEGF labeling index (LI) (P < 0.05). The patients with high VEGF LIs (LI >or= 25%) had a poor prognosis. VEGF expression was significantly related to that of iNOS (P < 0.001), i.e., VEGF level was reduced along with the decrease of iNOS reaction. CONCLUSION: Detection of FVIIIRAg could reflect the angiogenesis activities in astrocytomas. VEGF and iNOS could up-regulate each other to promote angiogenesis and are of importance in determining the malignancy degree of astrocytomas.

Astrocytoma↗
PubMed2001

[Immunorelated pancytopenia].

OBJECTIVE: A report of a group of patients with pancytopenia which might be related to abnormal immunity. METHODS: The clinical and laboratory features of 29 patients with positive bone marrow mononuclear cell (BMMNC) Coombs tests were analyzed. RESULTS: Most of these cases were pancytopenia with normal or decreased bone marrow cellularities and increased normoblasts. They were all found to have negative results of conventional hemolysis tests and hematopoietic nutrient determination and had no evidence of malignant clonal hematopoiesis. However, all of them showed positive BMMNC-Coombs test and good response to corticosteroids. CONCLUSION: Immunorelated pancytopenia might be caused by abnormal immunity (especially autoantibody) mediated destruction or abnormal function of blood cells. It is beneficial to differentiate immunorelated pancytopenia from aplastic anemia or myelodysplastic syndromes.

Adolescent↗
PubMed2001

[Study of C807T polymorphism of the platelet collagen receptor alpha2 gene coding sequence in Suzhou Han population].

OBJECTIVE: To study the C807T polymorphism of the platelet collagen receptor alpha(2) gene coding sequence in Suzhou Han population. This polymorphism was associated with the expression density of integrin alpha(2)beta(1) on the platelet surface. METHODS: An amplified 1332 bp fragment of human alpha(2) gene from 110 unrelated individuals was analyzed by Bgl II and Ase I restriction assay. The resulting products were electrophoresed in 8% polyacrylamide gels and stained with ethidium bromide. RESULTS: The allelic frequencies were 0.291:0.709 for T807 allele: C807 allele in Suzhou Han population. The total theoretical heterozygous rate was 41%. The genotypic frequencies were 0.018:0.546:0.436 for homozygous 807T allele: heterozygous 807C/T allele: homozygous 807C allele. CONCLUSION: The C807T polymorphism of the platelet collagen receptor alpha2 gene in Suzhou Han population was different from that observed in other populations.

Asian People↗
PubMed2001

[Sequential intensified immunosuppressive therapy combining with hematopoietic growth factors in the treatment of severe aplastic anemia].

OBJECTIVE: To explore more effective regimen for reducing early mortality of severe aplastic anemia (SAA) and improving therapeutic effectiveness. METHODS: Antilymphocyte globulin/antithymocyte globulin (ALG/ATG) and cyclosporine A (CsA) (sequential intensified immunosuppressive therapy, SIIST), with or without hematopoietic growth factors (HGFs) were administered to 73 SAA patients in a prospective randomized clinical trial to test the effectiveness of the addition of HGFs for the patients. RESULTS: The response rate of SIIST with HGFs group was significantly higher than that of SIIST alone group (89.2% vs 63.9%), with lower rates of early infection (24.3% vs 55.3%) and mortality (4.0% vs 16.7%), shorter duration of cytopenia and blood transfusion dependence and faster recovery of bone marrow hematopoiesis. The addition of HGFs to SIIST was tolerated well in all patients. There was no difference in the treatment outcome of the two groups with GM-CSF plus Epo or G-CSF plus Epo. CONCLUSION: The use of HGFs in combination with SIIST could reduce early infection and mortality rates and, therefore, improve the response rates in SAA patients.

Adolescent↗
PubMed2001

[Study on the transformation from myelodysplastic syndromes into acute leukemias].

OBJECTIVE: To study the patterns of transformation from myelodysplastic syndromes (MDS) into acute leukemias (AL). METHODS: Leukemic transformation of MDS patients was dynamically followed up and the clinical manifestations, peripheral blood and bone marrow pictures, karyotypes, immunophenotypes, response to treatment and prognosis of post MDS acute leukemia (postMDS-AL) were observed. RESULTS: During the past eight year and seven months, 21 (13.91%) of 151 MDS patients progressed to overt leukemia with a median interval of 5 (1 - 21) months. There were no significant differences among the rates of leukemia from RA, RAEB and RAEB-t groups. The transformation was developed either gradually or rapidly. There were five parameters related to the leukemic transformation: under 40 years of age, pancytopenia, more than 0.15 blasts in bone marrow, at least two types of abnormal karyotype and combined chemotherapy. All of the 21 post MDS-AL were acute myeloid leukemia (AML); and most of them were M(2), M(4) and M(5). Two (9.52%) post MDS-AML developed extramedullary infiltration. Leukopenia was found in 47.62% of patients. Two third of the patients, whose bone marrows were generally hypercellular, showed neutropenias. After evolving into AML, 8 (47.06%) patients developed abnormal karyotypes. High expression of immature myeloid antigens, including CD(33) (49.83 +/- 24.50)%, CD(13) (36.38 +/- 33.84)%, monocytic antigen CD(14) (38.50 +/- 24.60)%, and stem cell marker CD(34) (34.67 +/- 30.59)% were found on bone marrow mononuclear cells of post MDS-AML cases. In some cases, lymphoid antigens, such as CD(5), CD(7), CD(9) and CD(19) were coexisted with myeloid antigens. A low complete remission rate (31.25%) and short survival duration with median survival of 6 (1 - 28) months were found in patients with post MDS-AML treated by induction therapy. CONCLUSION: MDS was at high risk of evolving into AML, either gradually or rapidly. Patients with post MDS-AML had specific biologic features and worse prognoses.

Acute Disease↗
PubMed2001

[Effect of lower body negative pressure and rotating-table simulated push-pull effect in flight on cardiovascular function].

Objective. To explore the effect of push-pull effect (PPE) simulated by lower body negative pressure (LBNP) rotating-table, and observe the physiological responses to push-pull maneuver. Method. A special LBNP rotating-table was used to simulate the push-pull maneuver. 8 healthy adults participated randomly in two experiments. One was simulated PPE test, which include a series of head-up stand (HUT, +1 Gz) for 1 min, then in head-down stand (HDT, -1 Gz) for 30 s and again in HUT combining LBNP (-50 mmHg) for 10 min. The other one was control test, which only consists of HUT combining LBNP (-50 mmHg) for 10 min. Changes of heart rate (HR), blood pressure (BP), basic impedance (Z0) , stroke output (SO) , cardiac output (CO) and total peripheral resistance (TPR) were monitored by electrical impedance instrument during the experiment. Result. During simulated PPE experiment, 3 subjects presented presyncopal symptoms, with average standing time of 8.99 +/- 1.47 min, while during control test, all the subjects completed HUT combining LBNP for 10 min. In simulated PPE experiment, as compared with HUT (control), HR, Z0 during HDT were significantly lowered, while SV and CO were increased significantly. During HUT + LBNP, HR, Z0 and TPR were significantly higher, while SV and CO were significantly lower than that of control and HDT. SBP was increased significantly than control value when "HUT + LBNP" started, but during the whole process of "HUT + LBNP ", it became significantly lowered. In control experiment, the above mentioned indexes showed the same trend of as change compared with the control, however, the percentage of the change was lower than simulated PPE test, the change percentage in HR was not including. Conclusion. After headstand, head-up stand combining LBNP caused cardiovascular function descends, the degree was larger than simple head-up stand combining LBNP. LBNP rotating-table can be used to simulated push-pull effect.

Adult↗
PubMed2001

[Studies on chemical constituents from the flower of Citrus aurantium].

The chemical constituents from the flower of Citrus aurantium were studied. 11 compounds were isolated and identified including neohesperidin(I), synephrin(II), 5,8-epidioxyergosta-6,22-dien-3 beta-ol(III), adenosine(IV), asparagine(V), tyrosine(VI), valine(VII), isoleucine(VIII), alanine(IX),beta-sitosterol(X) and beta-daucosterol(XI).

Citrus↗
PubMed2001

[Immediate microcirculation reaction of periodontal ligaments to experimental intrusion of dog teeth].

OBJECTIVE: The purpose of this study is to investigate the immediate microcirculation reaction of periodontal ligaments to experimental intrusion of dog teeth. METHODS: The forth premolar was chosen as the anchor tooth to intrude the second premolar using an intrusion circle loop. All tissue sections were observed and analyzed using the ink perfusion technique and an image analysis apparatus. RESULTS: The microvascular pattern of periodontal ligaments was changed after the maxillary second premolar had been intruded for 2 hours with 100 g of force. The vascular diameter and volume density diminished, but the vascular number and some parts of the microvasculature, especially capillaries were compressed due to the blood escaping from the periodontal ligament. It showed that the initial effect of 100 g of intrusive force caused adaptable changes in the microcirculation of periodontal ligaments, but no significant impediment of blood flow occurred. CONCLUSION: During the tooth intrusion with 100 g of force, a suitable microenvironment was established for the benefit of the survival of periodontal ligaments, which could avoid overloads imposed on the periodontal ligament and decreased the injury of periodontal tissue. It elucidates that the microcirculation of periodontal ligaments plays an important role in the protection of the periodontal tissue, in terms of biological function.

Animals↗
PubMed2001

[The analysis of long-term curative effect in 201 cases of endoscopic sinus surgery].

OBJECTIVE: To analyze the long-term curative effect of endoscopic sinus surgery (ESS), and to study the factors related to the defeat of endoscopic sinus surgery. METHOD: 201 cases (353 sides) of chronic sinusitis and nasal polyps were treated with ESS, and were treated by taking the nasal cavity as a whole unit. RESULT: Following up survey from 12 months to 24 months postoperatively, it was found that 108 cases were cured (53.7%), 82 cases achieved symptomatic relief(40.8%), 11 cases remained failure (5.5%). CONCLUSION: It is very important to improve the ESS technique in order to reduce the recurrence of nasal polyps and sinusitis and to improve the curative effect of ESS, in addition, the treatment after operation is also indispensable to successful surgery.

Adolescent↗
PubMed2001

[Relationship between operative time and therapeutic effectiveness after the optic nerve injuries].

OBJECTIVE: To understand the relationship between the operative opportunity and effectiveness in the optic nerve injuries. METHOD: Twenty-three cases with optic nerve injuries were undertaken optic canal decompression. RESULT: The visual acuity in 13 cases were improved after the operation, and progressed about 0.233 averagely. The average time from injuries to operations was (12.90 +/- 16.77) d (3-22 d) in ineffective group. 7 cases of hypoactivity of eyeball recovered in 8 cases. CONCLUSION: The optic nerve decompression should be done after the patients were treated with megadose of steroid for 48 hours and did not recover. The time had better be no more than 7 days.

Adolescent↗
PubMed2001

[The epoxidation of cis-propenylphophonic acid to fosfomycin by Pencillium sp].

One strain of Penicillium sp. F5, found from soil sample, was able to stereo-specific epoxidation of cis-propenylphosphonic acid(PPOH) to fosfomycin[(-)-(1R, 2S)-1, 2-epoxypropylphosphonic acid, FOM] during the cultivation. The product (FOM) was identified by thin layer chromatography and microbiological assay. Under the culture conditions of 28 degrees C pH7.5 and 280 r/min, 0.3% concentration of PPOH, reached a level of 2.2 mg/ml of FoM and the yield was 41%. When the PPOH concentration was 0.6%, the yield was 8%.

Biotransformation↗
PubMed2001

[Selection of beta-glucanase-producing Trichoderma köningii T199 and its fermentation conditions].

A mutant strain T199 producing about 8 times as much beta-glucanase as its parent strain trichoderma köningii T3 was obtained by treatment with ultraviolet light and N-methyl-N-nitro-N-nitrosoguanidine. Fermentation was conducted in 250 mL flask, each containing 30 mL of medium consisted of 5% corn cob powder, 3% wheat bran and 1.4% nitrogen source No. 10 ((NH4)2SO4 10%, Peptone 20%, Yeast extract 15%). The optima culture conditions were as below: initial pH 5.0, 30 degrees C, shaking speed 280 r/min, and cultivation time 5 d. Enzyme activity toward CMC-Na, lichenin, laminarin and barley beta-glucan at pH 5.0 and 60 degrees C for 10 min were 300, 1100, 12 and 1600 IU/mL, respectively. The optima pH and temperature for enzyme action toward barley beta-glucan were pH 5.0 and 70 degrees C, respectively. The enzyme was stable under below 50 degrees C and at pH 4.5-6.5.

Cellulase↗
PubMed2001

[Determination of trace mercury in the liquorice by cold atomic fluorometry].

By applying the nondispersive apparatus with reduction and gasification, and the wet dissolving method, the trace mercury in liquorice is determined by cold atomic fluorometry. We studied the conditions that can affect the determined results. We compared two methods for cleaning the glass ware, and contrasted the working curve method with addition plotting method. We also studied the applicability of this experimental method. The recovery is 86.9%-110.8%, and the error is less than 13.1%. It proves the method is efficient and satisfactory.

Drug Contamination↗
PubMed2001

[Cloning of the genes associated with the pathogenesis of pregnancy induced hypertension using subtractive hybridization].

OBJECTIVE: To clone the genes related to pregnancy induced hypertension (PIH) for the study of PIH pathogenesis. METHODS: The differential expressed cDNA of PIH and normal pregnant placenta were cloned using modified polymerase chain reaction based subtractive hybridization. The differential cDNA were sequenced. RESULTS: Among 86 clones from subtractive hybridization, 14 clones containing differential expressed gene fragments in PIH and normal placenta were identified, and these might be the genes associated with PIH. Compared with the expressed sequence tags (EST) in dbEST of National Center for Biotechnology Information, it showed that 11 of them were known gene fragments, and three were unknown. The three unknown gene fragments were registered in GenBank, the accession number is AF 232216, AF 232217, AF 233648 respectively. CONCLUSIONS: Fourteen PIH related genes were cloned with subtractive hybridization. A new approach to study on the pathogenesis of PIH is presented.

Cloning, Molecular↗
PubMed2000

Energetic and functional contribution of residues in the core binding factor beta (CBFbeta ) subunit to heterodimerization with CBFalpha.

Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in several developmental pathways, including hematopoiesis and bone development. Mutations in CBF genes are found in leukemias and bone disorders. CBFs consist of a DNA-binding CBFalpha subunit (Runx1, Runx2, or Runx3) and a non-DNA-binding CBFbeta subunit. CBFalpha binds DNA in a sequence-specific manner, whereas CBFbeta enhances DNA binding by CBFalpha. Recent structural analyses of the DNA-binding Runt domain of CBFalpha and the CBFbeta subunit identified the heterodimerization surfaces on each subunit. Here we identify amino acids in CBFbeta that mediate binding to CBFalpha. We determine the energy contributed by each of these amino acids to heterodimerization and the importance of these residues for in vivo function. These data refine the structural analyses and further support the hypothesis that CBFbeta enhances DNA binding by inducing a conformational change in the Runt domain.

Amino Acids↗
PubMed2000

Intracerebroventricular injection of senktide-induced Fos expression in vasopressin-containing hypothalamic neurons in the rat.

Intracerebroventricular injection of senktide, a selective agonist for neurokinin B receptor (NK3), induced Fos expression in many neurons of the rat hypothalamus. Fos-positive neurons were predominantly present in the supraoptic and paraventricular hypothalamic nuclei, and some of them were seen in the lateral preoptic area, lateral hypothalamic area, arcuate nucleus, perifornical region, posterior hypothalamic area, circular nucleus, and along relatively large blood vessels (lateral hypothalamic perivascular nucleus) in the anterior hypothalamus. A double labeling study was performed to examine if vasopressin-containing neurons in the hypothalamus could be activated by the treatment. Neurons with both Fos-like immunoreactivity (-LI) and vasopressin-LI were found in the paraventricular nucleus, supraoptic nucleus, circular nucleus and lateral hypothalamic perivascular nucleus. In the supraoptic nucleus, about 87% of vasopressin-containing neurons exhibited Fos-LI, which corresponded to about 64% of Fos-positive neurons in the nucleus. In the paraventricular nucleus, about 80% of vasopressin-like immunoreactive neurons exhibited Fos-LI, which constituted about 51% of the total population of Fos-positive neurons in the region. The results suggest that NK3 receptor may be involved in the modulation of release of vasopressin from the hypothalamus in the rat.

Animals↗
PubMed2000

Decreased constitutive nitric oxide synthase, but increased inducible nitric oxide synthase and endothelin-1 immunoreactivity in aortic endothelial cells of donryu rats on a cholesterol-enriched diet.

The Donryu rat is resistant to a high cholesterol diet in that typical atheromatous lesions do not develop. Using electron microscopic immunocytochemical techniques, the effects of a CCT diet (4% cholesterol with 1% cholic acid and 0.5% thiouracil) on the distributions of neuronal, macrophage, and endothelial specific nitric oxide synthase (NOS I, NOS II, and NOS III) and endothelin-1 (ET-1) immunoreactivity were examined in the thoracic aortic intima. Atheromatous lesions were absent, but immunocytochemistry showed 1. 4+/-0.52% and 4.0+/-0.9% endothelial cells (EC) with positive staining for NOS I and NOS III, respectively, compared with 16.3+/-2. 5% and 88.6+/-2.48% in control Donryu rats. The CCT-supplemented diet induced expression of NOS II immunoreactivity in thoracic aortic intimal cells. EC, subendothelial macrophages, and smooth muscle cells (SMC) also showed high NOS II-positive staining. The percentage of NOS II-immunoreactive EC was 43+/-1.8%. In control groups, no NOS II immunoreactive cells were observed. The percentage of ET-1 immunopositive cells was also significantly increased by 9. 2+/-0.66% and 64.2+/-1.4% in control and CCT-fed groups, respectively. It is concluded that the administration of a high cholesterol diet in Donryu rats produces endothelial dysfunction associated with changes in the balance of the different isoforms of NOS and ET-1. Therefore, the increase in inducible NOS and ET-1 immunoreactivity seen during the cholesterol-enriched diet appears to be a compensatory reaction of aortic wall cells to the high cholesterol supplementation.

Animals↗