Crystal structures of and displacive transitions in OsN2, IrN2, RuN2, and RhN2.
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Journal Article↗
Biomedical subjects
Rong Yu
Publications and source records attributed to Rong Yu.
The effect of L-stepholidine, a novel extract of Chinese herb, on the acquisition, expression, maintenance, and re-acquisition of morphine conditioned place preference in rats.
The effect of L-stepholidine (SPD), a novel alkaloid extract of the Chinese herb Stephania with partial dopamine D1 receptor agonistic and D2 receptor antagonistic dual actions, on morphine conditioned place preference (CPP) was studied. Daily injection of morphine (10 mg/kg, i.p.) for 6 days induced CPP in rats, and daily treatment with SPD at 10 or 20 mg/kg before morphine injection dose-dependently attenuated morphine-induced CPP. On the day following acquisition of morphine CPP, a single administration of SPD at 10 or 20 mg/kg failed to block the expression of CPP. However, daily administration of SPD at 20 mg/kg for 7 days attenuated the maintenance of CPP. Morphine-induced CPP extinguished after a 21-day saline training and then a single injection of morphine (3 mg/kg, i.p.) induced re-acquisition of morphine CPP; however, pretreatment with SPD at 10 or 20 mg/kg 30 min before morphine injection dose-dependently blocked morphine (3 mg/kg, i.p.)-induced re-acquisition of morphine CPP. Furthermore, our data indicate that SPD had no effect on food-induced CPP or state-dependent learning, suggesting that the observed effect of SPD does not result from an inhibition of general learning ability. These results demonstrate that SPD can inhibit acquisition, maintenance, and re-acquisition of morphine conditioned place preference and suggest its potential for treatment of opioid addiction.
Analgesics, Opioid↗
A method for purification and viral inactivation of human placenta hemoglobin.
For pilot-scale manufacturing of hemoglobin-based oxygen carrying drugs, we should get highly pure and viral inactivated hemoglobin (Hb) at high recovery. In our method, placenta hemoglobin (PHb) solutions were purified by heating in the presence of reducing agent and deoxygenating conditions so that heat-sensitive proteins were selectively precipitated and virus was inactivated. The optimum preparative condition resulted in highly purified PHb solution (>99% pure) with approximate 90% recovery and less than 2% of MetHb content, maintained oxygen carrying capacity, residual phospholipids less than 1 ppm, free of endotoxin, bacteria, type A&B antigens and virus. Finally, we compared the efficacy of blood exchange on rat with poly-PHb and poly-Hb from adult blood. The results showed no significant difference between two products. Therefore, the placenta Hb obtained from this method could be supplied as materials for oxygen carrying drugs.
Animals↗
[Expression of heparanase and angiopoietin-2 mRNA in endometriosis].
OBJECTIVE: To investigate the relationship between heparanase (Hpa) and angiopoietin-2 (Ang-2) gene expression and the development of endometriosis (EM). METHODS: Expression of Hpa gene and Ang-2 mRNA in the eutopic and ectopic endometrium collected from 86 patients with endometriosis (EM group) and the normal endometrium from 30 women without endometriosis (control group) was determined by RT-PCR. RESULTS: (1) Hpa gene expression was detected in 53 ectopic endometrium and 47 eutopic endometrium specimens in the EM group and 8 normal endometrium specimens in the control group. There was no significant difference in Hpa gene expression between ectopic and eutopic endometrium in the EM group (P > 0.05). However, the Hpa gene expression in normal endometrium in the control group was significantly lower than that in ectopic and eutopic endometrium in the EM group (P < 0.05). (2) Ang-2 gene expression was detected in 61 ectopic endometrium and 56 eutopic endometrium specimens in the EM group and 10 normal endometrium specimens in the control group. There was no significant difference in Ang-2 gene expression between ectopic and eutopic endometrium in the EM group (P > 0.05), however, the Ang-2 positive rate in normal endometrium in the control group was significantly lower than that in ectopic and eutopic endometrium in the EM group (P < 0.05). (3) The expression of Hpa gene in stage III-IV endometriosis was significantly higher than that in stage I-II endometriosis (P < 0.05). (4) The difference of Ang-2 mRNA expression between stage III-IV and stage I-II endometriosis was not significant (P > 0.05). (5) The expression of Hpa gene was shown to be significantly correlated to the expression of Ang-2 gene in ectopic endometrium specimens from patients with endometriosis (P < 0.05). CONCLUSION: Hpa and Ang-2 genes are highly expressed in both ectopic and eutopic endometrium of patients with endometriosis. Over-expression of these two genes may play a role in the development and progression of endometriosis.
Adult↗
[Purification and viral inactivation of hemoglobin from human placenta blood].
This study was intended to establish a method for preparation of purified and viral-inactivated placenta hemoglobin. The optimum preparative condition resulted in the up-grading of purity,recovery and so on. A quality control was also established for the purification of hemoglobin. Compared to present purification methods, this method is easy to operate, needs low investment and running cost, and has the advantage of simultaneous operation for purification and viral-inactivation. The resulted hemoglobin had high purity and recovery, and the physicochemical property measured up to that in international reports. So this method is suitable for preparing purified and viral-inactivated hemoglobin on an adequate scale, and is useful for further development of blood substitutes.
Blood Substitutes↗
Quantum percolation in two-dimensional antiferromagnets.
The interplay of geometric randomness and strong quantum fluctuations is an exciting topic in quantum many-body physics, leading to the emergence of novel quantum phases in strongly correlated electron systems. Recent investigations have focused on the case of homogeneous site and bond dilution in the quantum antiferromagnet on the square lattice, reporting a classical geometric percolation transition between magnetic order and disorder. In this study we show how inhomogeneous bond dilution leads to percolative quantum phase transitions, which we have studied extensively by quantum Monte Carlo simulations. Quantum percolation introduces a new class of two-dimensional spin liquids, characterized by an infinite percolating network with vanishing antiferromagnetic order parameter.
Journal Article↗
Thermal wetting of platinum nanocrystals on silica surface.
Thermal stability of facetted Pt nanocrystals on amorphous silica support films was investigated using in situ transmission electron microscopy in a temperature range between 25 and 800 degrees C. The particles started to change their shapes at approximately 350 degrees C. Above 500 degrees C, the particles spread on the support film with increasing temperature, rather than becoming more spherical. Such temperature-induced wetting of Pt nanoparticles on silica surface can be attributed to the interfacial mixing of Pt and SiO(2) and the resulting negative interface energy.
Journal Article↗
Age-dependent onset of liver-specific IGF-I gene deficiency and its persistence in old age: implications for postnatal growth and insulin resistance in LID mice.
To explore the limitations of the liver-specific IGF-I gene-deficient (LID) model and to further evaluate the role of endocrine IGF-I in early postnatal life and old age, we have studied these mice during the prepubertal period (from birth to 3 wk of age) and when they are 2 yr old. During the first 2 wk of life, IGF-I gene deficiency and the resulting reduction in serum IGF-I levels in LID mice did not reach sufficiently low levels when mice experience the most rapid and growth hormone (GH)-independent growth. It suggests that the role of liver-derived IGF-I in prepubertal, GH-independent postnatal growth cannot be established. From our previous studies, liver IGF-I mRNA level was abolished in adult LID mice, which causes elevated GH level, insulin resistance, pancreatic islet enlargement, and hyperinsulinemia. Interestingly in 2-yr-old LID mice, although liver IGF-I mRNA and serum IGF-I levels were still suppressed, serum insulin and GH levels had returned to normal. Compared with same-sex control littermates, aged male LID mice had significantly reduced body weight and fat mass and exhibited normal insulin sensitivity. On the other hand, aged female LID mice exhibited normal weight and marginal resistance to insulin actions. The pancreatic islet percentage (reflecting islet cell mass) was also restored to normal levels in aged LID mice. Thus, although the IGF-I gene deficiency is well maintained into old age, the insulin sensitivity, islet enlargement, and hyperinsulinemia that occurred in young adult mice have been mostly restored to normal levels, further supporting the age-dependent and sexual dimorphic features of the LID mice.
Aging↗
Clonal dynamics of tumor-infiltrating lymphocytes.
The presence of tumor-infiltrating lymphocytes (TIL) provides important evidence of anti-tumor immunity in vivo. However, TIL are usually not sufficient for inhibiting tumor growth. We explored the spatial and temporal aspects of clonal accumulation of TIL using RT-PCR/single-strand conformation polymorphism analysis. In CMS5 fibrosarcomas in BALB/c mice, accumulated T cell clones were specific in that dominant TIL were identical between distant tumors. Moreover, dominant TIL in the first tumor appeared consistently in the second tumor inoculated after formation of the first tumor. These results suggest that TIL show a certain level of specific tumor surveillance. When we characterized CD4(+) and CD8(+) TIL separately, CD8(+) TIL were highly concentrated and persistently localized at the tumor site, while most CD4(+) TIL clones were less concentrated and less persistent. A functional analysis showed that TIL had a certain degree of anti-tumor activity when CD4(+) and CD8(+) TIL were co-transferred. Co-transfer of CD4(+) and CD8(+) TIL exhibited equivalent anti-tumor activity, irrespective of tumor stage. However, the numbers of TIL did not increase after the early phase of tumor progression. These data suggest that TIL are specific to the tumor and potentially retain anti-tumor activity, although their accumulation in mice is impaired.
Animals↗
Thermally driven interfacial dynamics of metal/oxide bilayer nanoribbons.
Solid-solid interfacial processes greatly affect the performance of electronic and composite materials, but probing the dynamics of buried interfaces is challenging and often involves lengthy or invasive sample preparation. We show that bilayer nanoribbons-made here of tin dioxide and copper-are convenient structures for observing as-made interfaces as they respond to changing temperature in a transmission electron microscope (TEM). At low temperatures (<200 degrees C), differential thermal expansion causes the bilayers to bend when heated or cooled, with the motion determined by the extent of Cu-SnO(2) epitaxy. At higher temperatures, we are able to watch-in real time and with nanometer resolution-a progression of grain growth, interdiffusion, island formation, solid-state chemical reactions, and melting. This novel TEM geometry is readily applicable to other nanoribbon/coating combinations and is well suited to observing interfacial phenomena driven thermally or by the application of mechanical, electrical, or magnetic forces.
Alloys↗
A novel alkaloid from Mitrephora maingayi.
A novel alkaloid, maingayinine, together with dicentrinone, dicentrinene, L-2-O-methyl-chiro-inositol, allantoin, glaucine, N-phenyl-2-naphthylamine, terephthalic acid and ayanin, was isolated from the twigs of Mitrephora maingayi Hook (Annonaceae). Their structures were established predominantly by IR, MS and NMR spectral data.
Annonaceae↗
[Preliminary studies on in vitro and in vivo thrombolytic activities of thrombolytic enzyme from an induced Bacillus subtilis strain].
OBJECTIVE: To separate and purify a novel thrombolytic enzyme (FSC2-13) from culture media of an induced Bacillus subtilis strain and to study its in vitro and in vivo thrombolytic activities. METHODS: Employed fibrin plate method, pyrogenation (heating up) fibrin plate method and SDS-PAGE were used respectively to study FSC2-13 hydrolyzing fibrin and fibrinogen in vitro. Investigations were made on its in vivo pharmacodynamics using rat thrombogenesis inhibition model after it was administrated by intestinal route. RESULTS: FSC2-13 could hydrolyze fibrin and fibrinogen in vitro and had hydrolysis sites on three peptide chains of fibrinogen. FSC2-13 could significantly inhibit the formation of rat venous thrombus after being administrated by intestinal route. Thrombogenesis inhibition rate was 68%. Activated partial thromboplastin time increased by 51%, fibrinogen content decreased by 49%, fibrin degradation product (FDP) content also increased obviously, but the plasminogen content did not change obviously. CONCLUSION: FSC2-13 possessed in vitro and in vivo thrombolytic activities in a special way. There seem to be prospects for researches to develop it into a new generation of oral thrombolytic drug.
Animals↗
[Expression of androgen receptor on fibroblast and hepatocyte of rats after deep second-degree burn caused by scalding].
OBJECTIVE: To investigate the effect of protein anabolic hormone on fibroblast and hepatocyte of rat and the mechanism therein involved. METHODS: Thirty-two Wistar rats with deep second-degree scald injury of 20% total body surface area (TBSA) were randomly divided into two groups to receive either 5 mg/kg of an anabolic steroid--nandrolone phenylpropionate (NP group) or normal saline as placebo (control group) every other day. Mean Integrated Optical Density (mIOD) of androgen receptor (AR) in fibroblast and hepatocyte of rats were measured by immunohistochemistry individually on the post-burn days 4, 7, 14 and 21. RESULTS: The expression levels of AR on fibroblast and hepatocyte in NP group were significantly higher than those in the control group respectively. CONCLUSION: Nandrolone phenylpropionate can enhance the expression and activation of AR on fibroblast and hepatocyte.
Animals↗
Effects of GM-CSF, IL-3, and GM-CSF/IL-3 fusion protein on apoptosis of human myeloid leukemic cell line Tf-1 induced by irradiation.
AIM: To observe the effects of three cytokines on the apoptosis of Tf-1 cells induced by gamma irradiation and investigate the relationship between apoptosis and caspase-3 activity. METHODS: Different cytokines GM-CSF, IL-3 and GM-CS/IL-3 fusion protein were added into the irradiated Tf-1 cells. MTT assay, morphology, flow cytometry, and DNA fragmentation assay were used to observe the effects of cytokines on apoptosis. The caspase-3 activity was determined with a fluorocytometer. RESULTS: Irradiated Tf-1 cells showed typical morphological characteristic of apoptosis demonstrated by transmission electron microscopy and were accumulated in G0/G1 phase. In the groups treated with growth factors after irradiation, three cytokines significantly increased the viability rate, distinctly decreased the apoptosis rate and the proportion of DNA fragmentation. When Tf-1 cells were irradiated by gamma irradiation, caspase-3 activity was increased at different time points. In comparison with the control group in which no growth factor was added after the cells were irradiated, the caspase-3 activity of irradiated Tf-1 cells was significantly inhibited by addition of the above cytokines. Thirty-six hours after irradiation, in the control group, GM-CSF, IL-3, GM-CSF and IL-3 in combination, and two GM-CSF/IL-3 fusion protein groups, the apoptosis rate was 73 %, 11 %, 15 %, 13 %, 12 %, and 13 %. The percent of fragmented DNA was 36 %, 19 %, 18 %, 14 %, 13 %, and 14 %. The fluorescence intensity was 16923, 5529, 6581, 5322, 5426, and 5485. CONCLUSION: GM-CSF, IL-3, and GM-CSF/IL-3 fusion protein could protect Tf-1 cells from apoptosis induced by gamma irradiation. After Tf-1 cells were irradiated, the caspase-3 activity was significantly increased but was dramatically decreased by the above cytokines. The remarkable inhibition of caspase-3 activity may be one of the mechanisms of these hematopoietic growth factors exerting their anti-apoptotic effects.
Apoptosis↗
[Magnetic resonance imaging findings in children with cerebral palsy].
OBJECTIVE: To study the clinical and neurological abnormalities in children with cerebral palsy (CP) and to attempt to correlate the types of CP and the gestational age at birth with radiological abnormalities detected by magnetic resonance imaging (MRI) of the brain. METHODS: This is a hospital-based study, the subjects included 104 children with cerebral palsy who were hospitalized in the Qingdao Rehibilitation Center For Disabled Children. All the 104 hospitalized CP cases (47 with spastic diplegia, 9 with tetraplegia, 15 with hemiplegia, 22 with athetosis, and 11 with ataxia) were examined neurologically and their perinatal history was reviewed. Their cranial MRI findings were studied. The association between the gestational ages, CP types, and the radiological findings were studied. RESULTS: The type distribution was significantly different between term- and preterm- infants. Spastic diplegia was the main type in preterm infants while hemiplegia and ataxia were mainly seen in term infants. MRI abnormalities were found in 88 of the 104 cases and abnormal rates of spastic diplegia, tetraplegia, hemiplegia, athetosis, and ataxia were 89.4%, 100%, 100%, 54.5% and 90.9%, respectively. There was no significant difference in abnormal rates between term and preterm groups. Thirty-one of 42 (73.8%) children with spastic diplegia had significant periventricular leukomalacia (PVL), which was more common among preterm-born children (90%). Of the 15 children with hemiplegia, 13 had unilateral lesions on neuroimaging. Spastic tetraplegia was associated with extensive, bilateral, diffuse brain damage. The abnormalities in term-born infants with athetoid cerebral palsy were mainly located in the basal ganglia region whereas the major abnormality in premature infants was PVL. Of the 11 children with ataxic cerebral palsy, 8 cases showed congenital cerebellum dysplasia on brain imaging. CONCLUSIONS: Radiological abnormalities of the brain were correlated with CP types and the gestational age at birth; MRI scan was useful in revealing underlying brain abnormalities and speculating on the etiology of cerebral palsy.
Cerebral Palsy↗
[The roles of microtubule in internodal cell elongation (Nitellopsis obtusa)].
The relationship between cell elongation and microtubules (MTs) was investigated in characean internodal cells (Nitellops obtusa). First, we examined the immunofluorescent localization of MTs in different living stages under confocal laser scanning microscope. In young, rapidly elongating cells, MTs were predominantly transverse to the long axis of the cell. As the relative growth rate fell, transverse MTs gradually decreased, and in non-growing cells, longitudinally oriented cortical MTs became most pronounced. Moreover, cells in different living stages responded to the treatment of oryzalin (microtubule-disrupting agent) differently, young active internodal cells seemed to be more sensitive. After 40 min incubation of 10 micromol/L oryzalin, nearly all cortical MTs in the elongating cells depolymerized. However, in the old, non-growing cells, some MT fragments still remained after 3 h treatment of oryzalin. Second, we measured the cell growth rates with and without the treatment of oryzalin. In young growing cells treated with 10 micromol/L oryzalin, the elongation rates were inhibited obviously. When the oryzalin was removed, the elongation rates could be recovered to some extent. Interestingly, a time-gap existed between microtubule disassembly (40 min) and cessation of cell elongation (100 min). Our data confirmed the evidence that MTs are involved in cell elongation.
Characeae↗
[Preparation of recombinant human insulin--study of downstream process].
This study was intended to establish a method of preparation of recombinant human insulin, with (His)6-Arg-Arg-human proinsulin (RRhPI) expressed by Escherichia coli. After DEAE-Sepharose Fast Flow ion-exchange chromatography, Sephadex G-25 chromatography and refolding, enzyme cleavage and Superdex 75 size exclusion chromatography,the RRhPI expressed by Escherichia coli in inclusion body form was converted to human insulin. The obtained recombinant human insulin was analyzed by SDS-PAGE, HPLC, amino acid composition analysis and bioidentity test (mouse convulsion test). The results indicate that our obtained preparation is highly purified, active recombinant human insulin.
Chromatography, High Pressure Liquid↗
Liver-specific IGF-I gene deficient mice exhibit accelerated diabetes in response to streptozotocin, associated with early onset of insulin resistance.
Liver-specific IGF-I gene deficient (LID) mice exhibit pancreatic islet hyperplasia and insulin resistance. To clarify their causal relationship, we studied age-dependent changes in these two aspects and the response to beta-cell damage caused by streptozotocin in adult mice. As a result, the onset of insulin resistance in LID mice was detectable as early as 1-month of age, while hyperinsulinemia was developed after a significant delay at 2.5-month. Upon streptozotocin administration, control mice exhibited significant hyperglycemia after 9 days, and glucose levels continued to rise at 12-15 days. LID mice developed diabetes much more rapidly, with hyperglycemia after 6 days and higher glucose levels up to 15 days. They also exhibited significant weight loss and 6/19 died. Serum insulin assay, insulin mRNA analysis and immunohistochemistry revealed that the more severe diabetes in LID mice was not due to more damage to their beta-cells. Thus LID mice are more sensitive to streptozotocin-induced beta-cell damage, due to a primary defect in insulin responsiveness. The pancreatic islet hyperplasia observed in these mice seems to represent a compensatory response to insulin resistance, therefore, offers no protection against beta-cell damage.
Age of Onset↗