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Biomedical subjects

J Yu

Publications and source records attributed to J Yu.

At least 541 records · Page 30Linked to original sources
PubMed1997

[Experimental study of effect on tonifying kidney herbs in pituitary ovary adrenal gland of androgen sterilized rats].

OBJECTIVE: To observe the effect of tonifying Kidney herbs (TKH) in pituitary, ovary, adrenal gland of androgen sterilized rats(ASR). METHODS: ASR model was established by injecting testosterone propionate subcutaneously to SD female rats of 9 days age. Morphological and hormonal change of pituitary, ovary and adrenal gland in rats of 100-107 days old before and after feeding TKH extract were observed by light and electron microscope, cell culture immunohistochemical studies and radioimmuno-assay. RESULTS: In the ASR groups, there were intracytopiasmic lipid drops, autophagy, vacuole, granulolysis of pituitary gland. There were anovulation apparently and increased the amount of lipid drops in cytoplasm of interstitial glandular cell of ovary. The fatty drops of the reticular zone of adrenal gland decreased, the numbers of AGNOR (P < 0.01) and PCNA (P < 0.01) increased significantly. The levels of FSH, LH (P < 0.05-0.005) lowered, but the levels of DHA, T (P < 0.01, 0.05, 0.001) were raised significantly. Morphological and hormonal change of all RSA returned to normal range after the treatment. CONCLUSIONS: The hyperandrogenemia were disturbed by the function of sex gland axis and adrenal in female rats of 9 days old and played an important role in pathogenesis of ASR, the TKH reduced the levels of androgen and induced ovulation through sex gland axis and adrenal level and multi-organ regulation.

Animals↗
PubMed1997

[Somatostatin in NRM plays roles in inducing analgesia and enhancing electroacupuncture analgesia].

The effects of microinjection of somatostatin (SS), somatostatin depletor cysteamine (CS) and anti-somatostatin serum (ASSS) on the pain threshold (PT) and electroacupuncture (EA) analgesia were investigated in the rat. The potassium iontophoresis induced tail-flick was used to measure the pain threshold. The "Zusanli" were stimulated with EA. The results indicated that microinjection of SS into necleus raphe magnus (NRM), could elevate PT and enhance EA analgesia. PT and EA analgesia were decreased when SS in NRM was depleted by CS or neutralized by ASSS. These data revealed that SS in NRM plays important roles in inducing analgesia and enhancing electroacupuncture analgesia.

Acupuncture Analgesia↗
PubMed1997

[A study on relationship between chemotherapy of acute leukemia and apoptosis in vivo].

In order to investigate whether apoptosis occurs in vivo in patients with leukemia in different stage (before, during and after chemotherapy). We detect apoptosis of peripheral blood leukemia cells in 10 patients before, during and after chemotherapy with in situ TdT fluorescence measurement and DNA electrophoresis. The results showed that apoptotic cells were few (0-2.9%) before chemotherapy, increased obviously (11.4%-72.0%) during chemotherapy in patients with complete remission (CR) or partial remission (PR), but decreased (0-2.9%) after chemotherapy (10-14 days). Apoptotic cells were few (0-5.7%) during chemotherapy in four patients without remission. Therefore, only effective drug therapy could induce apoptosis. DNA ladder cannot be detected by agarose gel electrophoresis either before, during and after chemotherapy. So we considered that in situ TdT assay is possible to apoptosis in vivo in the early course of chemotherapy for immediate modification of chemotherapy, while electrophoretic analysis is not sensitive enough to detect apoptotic cells in vivo.

Adult↗
PubMed1997

[Influence of human bone morphogenetic protein (hBMP) on the articular cartilage pieces cultured in vitro].

To understand the influence of hBMP on the articular cartilage, we investigated the expression of osteocalcin (BGP) and hBMP, and calcium deposit in cartilage matrix induced by hBMP. Under the inducing of hBMP, chondrocytes in cartilage pieces begun to express BGP and hBMP. The hBMP promoted calcium deposition in the cartilage matrix, hBMP made some chondrocytes further differentiat into osteoblast-like cells. We consider that these osteoblast-like cells might be other source of osteoblasts in endochondral osteogenesis.

Bone Morphogenetic Proteins↗
PubMed1997

[Dormancy characteristic and inner inhibitory substances of fructus Schisandrae].

It has been found for the first time that there is quite a number inhibitory substances in the testa and kernel of dormant Fructus Schisandrae. Differences have alas been found between the inhibitor extracted from the testa and that from the kernel. The fromer is stronger in inhibiting the root elongatain of Brassica sp, whereas the latter is stonger in inhibiting the seeds germination. The result shows that the dormancy of Fructus Schisandrae the inhibitors contained in the testa and kernel.

Brassica↗
PubMed1997

[Clinical and pathological study on cervical lymph node metastasis of supraglottic cancer].

AIM: To study pathological features of cervical lymph node metastasis and the relationship between supraglottic cancer and cervical lymph node metastasis. METHOD: Observation of 100 whole-organ serial sections of the larynges and 170 sides of the radical neck dissection specimens. RESULTS: 1. Cervical lymph node metastasis 55 cases, metastatic rate 55%; 2. Four series of cervical metastasis: clinico-pathologic metastases (29 cases), pathologic metastases (26 cases), clinical metastases (5 cases), no metastasis (40 cases). 3. Four stages of metastatic lymphnode: early stage, growth stage, fullness stage and capsular perforative stage; 4. Three types of metastases: single type (21 cases), multiple type (10 cases) and aggregated (24 cases) type. 5. Metastatic rates of supraglottic cancer of different regions: aryepiglottic fold 85.7%, arytenoid cartilage area 66.6%, epiglotto-ventricular fold 56.8%, epiglottic 46.4%, ventricular fold 45.4%. 6. When the tumour spread to the perilaryngeal region, the metastatic rate was 80% to 84%. CONCLUSION: Metastatic rate of cervical lymph node is higher in supraglottic cancers, the aggregated type and capsular perforative stage are more in metastasis lymph nodes. Analysis the original sites of supraglottic cancer is conductive to the prediction of the cervical lymph node metastasis.

Glottis↗
PubMed1997

[Chemical constituents of fructus Amomi].

Seven compounds have been isolated from Fructus Amomi. They were identified as bornyl acetate, camphor, borneol, beta-sitosterol, vanillic acid, stearic acid and palmitic acid. The vanillic acid was found in this medicine for the first time. Fifty-seven components were identified from the volatile oil of Fructus Amomi on the basis of GC-MS analysis. Eight components in the volatile oil over 1% in content are bornyl acetate, camphor, borneol, limonene, camphene, myrecene, carene-3 and alpha-terpeneol.

Drugs, Chinese Herbal↗
PubMed1997

[Preliminary study of mitochondrial DNA deletions in age-related macular degeneration].

PURPOSES: To investigate mitochondrial DNA mutation associated with oxidative phosphorylation defect due to aging and to inspect it whether to play a role in the pathogenesis of age-related macular degeneration(ARMD). METHODS: Using polymerase chain reaction (PCR) analysis, the mitochondrial DNA deletions were detected on blood samples in 20 patients with age-related macular degeneration (ARMD) and in 10 controls. RESULTS: The abnormal mtDNA fragments in blood cells were amplified on 6 cases of wet ARMD that indicated there might be three types of mtDNA deletions between positions 7901 and 13,650. The sizes of mtDNA deletions were 3.67 kb, 5.0 kb and 5.2 kb respectively. No abnormal mtDNA fragments were amplified on 10 cases in control. CONCLUSIONS: It suggests that there were multiple mitochondrial DNA deletions on the blood cells of ARMD, including an aging-associated 5.0 kb deletion and it requires further studies on relationship between the mitochondrial DNA mutation and the etiology of ARMD.

Age Factors↗
PubMed1997

[Effects of neferine on platelet aggregation in rabbits].

Neferine (Nef), a hypotensive agent with antiarrythmic action, is a dibenzyl isoquinoline alkaloid isolated from a Chinese medicinal herb (Nelumbo nucifera Gaertn). Its effects on platelet aggregation and TXA2/PGI2 and cAMP/cGMP balance were studied with methods of turbidimetry and RIA. Nef was shown to significantly inhibit rabbit platelet aggregation induced by ADP, collagen, arachidonic acid (AA) and platelet-activating factor (PAF) with IC50 of 16, 22, 193 and 103 mumol.L-1, respectively. Nef was found to increase vascular 6-keto-PGF1 alpha and platelet cAMP levels in dose-dependent manner, but inhibit AA stimulated TXA2 release from platelets. Nef showed no significant effect on the platelet cGMP level. The results suggest that the mechanism of Nef on platelet aggregation is related to regulation of TXA2/PGI2 and cAMP/cGMP balance.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

Dynorphin A (1-8) analog, E-2078, is stable in human and rhesus monkey blood.

E-2078 is a dynorphin A (1-8) analog, [N-methyl-Tyr1, N-methyl-Arg7-D-Leu8] Dyn A (1-8) ethylamide. Its biochemical stability against enzymatic degradation in vitro in human and rhesus monkey blood, and in vivo in rhesus monkey blood was studied using matrix-assisted laser desorption/ionization mass spectrometry. In vitro studies were carried out in freshly drawn human and rhesus monkey blood, incubated at 37 degrees C for various time periods. In vivo studies were conducted by E-2078 i.v. injection to rhesus monkeys, and blood samples were collected at various time points after the injection. It was found that E-2078 was stable against enzymatic degradation in vitro in freshly drawn human and rhesus monkey blood. Minor biotransformation products from E-2078, such as E (1-4), E (1-5) and E (3-6), were detected in vitro in some human and rhesus monkey blood, but they made up less than 5% of the total starting E-2078 peptide. No biotransformation products were detected in the blood samples from in vivo studies. The apparent half-life of elimination of E-2078 in vivo from the rhesus monkey blood was determined to be 44.0 min.

Adult↗
PubMed1997

Paroxysmal nocturnal hemoglobinuria: new insights from murine Pig-a-deficient hematopoiesis.

A large fraction of the hematopoietic cells of patients with paroxysmal nocturnal hemoglobinuria (PNH) are deficient in membrane expression of glycosylphosphatidylinositol-anchored proteins (GPI-APs). Current evidence suggests that this deficiency is sufficient to account for the hemolytic and thrombotic manifestations of this disease but not for its frequent association with aplastic anemia, an autoimmune disorder in which the patients' own hematopoietic progenitor cells are the target. Mutations in X-linked gene PIG-A, encoding one of several enzymes required for the biosynthesis of the glycophosphatidylinositol anchor, have been found in all PNH patients studied to date. Recent experiments with murine Pig-a knock-out embryonic stem cells show that although embryogenesis is critically dependent on normal GPI-AP expression, Pig-a-deficient cells can undergo apparently normal hematopoietic differentiation if they develop in a GPI-AP-replete environment. Thus, in an in vitro mouse model of PNH, Pig-a mutations confer no gross proliferative or differentiative advantage or disadvantage, suggesting an unidentified process selecting for these mutations in the bone marrow of patients with the PNH-aplastic anemia syndrome. The rescue of hematopoiesis observed in chimeric cultures of knock-out and normal cells was accompanied by intercellular transfer of GPI-AP, suggesting exciting new possibilities for future therapeutic manipulations in PNH patients.

Animals↗
PubMed1997

Latex allergy in hospital employees.

The purpose of this study was to investigate the prevalence and risk factors of latex-allergy in hospital personnel and the presence of latex-specific IgE in a latex-allergic group in Taiwan. A total of 1,021 hospital employees were initially screened for latex allergy with a questionnaire, which included sex, age, job categories, number of years of employment, daily working hours, frequency of latex glove wearing, symptoms of immediate reactions to latex gloves and history of previous atopic diseases. Among them, 70 hospital employees (6.8%; 95% confidence interval 1.9%-11.8%) had symptoms associated with glove wearing. The frequencies in different job categories were 28.3% of surgical nurses, 9.2% of surgeons, 5.8% of regular floor nurses, 5.2% of technicians, 4.6% of physicians, and 4.5% of laboratory researchers. The symptoms were significantly related to the frequency of latex glove exposure, surgical work, current hand eczema and history of atopic dermatitis. In contrast, the number of years of employment, daily working hours and previous history of hand eczema were not correlated with the symptoms of latex allergy. Latex-specific IgE was assayed by the dot blot method in 36 hospital employees of the latex allergic group (positive rate, 55.6%). We concluded that the prevalence of latex-allergy among hospital personnel was 6.9% and certain predisposing factors such as atopic dermatitis, current hand eczema ad surgical work may play a critical role in triggering and aggravating the symptoms.

Adult↗
PubMed1997

Dynorphin A (1-8) analog, E-2078, crosses the blood-brain barrier in rhesus monkeys.

E-2078 is a dynorphin A (1-8) analog, [N-methyl-Tyr1, N-methyl-Arg7-D-Leu8] dynorphin A (1-8) ethylamide. Its ability to cross the blood-brain barrier was examined in rhesus monkeys using matrix-assisted laser desorption/ionization mass spectrometry. In vivo studies were carried out by i.v. injecting E-2078, 10 mg/kg, a dose that had been found to be antinociceptive, to rhesus monkeys. Blood and cerebrospinal fluid samples were collected at various time points after the injection. It was found that E-2078 was stable in vivo in rhesus monkey blood. No biotransformation products were detected in the blood. Mass spectrometric analysis of the cerebrospinal fluid samples collected after E-2078 injection detected the presence of E-2078, indicating that E-2078 had crossed the blood-brain barrier. These findings are consistent with the possibility that systemically administered E-2078 could produce centrally mediated behavioral and physiological effects.

Analgesics, Non-Narcotic↗
PubMed1997

Study of mathematical model for product formation with recombinant microbes expressed IFN.

Based on the known molecular interactions of aporepressor, corepressor, and inducer, a mathematical model of product formation about the Trp operon regulated recombinant microbes has been proposed. The linear relation of the overall transcription rate constant and overall translation rate constant on the specific growth rate has been suggested. We used experimental data where engineered microorganisms express interferon (IFN). Decay constant of IFN, mRNA transcription rate constant, and IFN expression rate constant have been estimated. An equation related to IFN concentration in fermentation on specific growth rate and Trp concentration has been obtained. By application of the equation, the expression of IFN is calculated based on Trp concentration and specific growth rate in fermentation. Also, the optimum overall culture time can be determined.

Escherichia coli↗
PubMed1997

Production of activin A and its roles in inflammation and hematopoiesis.

Activin A, a member of the transforming growth factor beta (TGF-beta) superfamily, is a protein consisting of two homodimeric beta A subunits. It was originally isolated from follicular fluid as a factor stimulating the release of follicle-stimulating hormone from the pituitary gland. Increasing evidence suggests that activin A is broadly distributed and regulates multiple functions in various biological systems by autocrine/paracrine mechanisms. In this review, we discuss the effects of activin A on hematopoiesis, especially the enhancement of erythropoiesis, and the production of activin A within the bone marrow microenvironment and in peripheral blood monocytes. The regulatory control of activin A expression by its 5' promoter region is also discussed. Furthermore, we consider that the expression of activin A is modulated by different agents, including proinflammatory cytokines, glucocorticoids and retinoic acid, suggesting new roles for activin A in inflammation reactions. Recently, this role in inflammation was further strengthened by the findings that activin A expression is elevated in inflammatory arthropathies, is regulated by inflammation-associated cytokines in synoviocyte and articular chondrocyte cultures, and is able to counteract many of the interleukin-6 (IL-6)-induced biological activities. Therefore it is likely that activin A may also act as a paracrine/autocrine moderator in diverse functions, including host defenses.

Activins↗