Dispersed SiC nanoparticles in Ni observed by ultra-small-angle X-ray scattering

A metal–ceramic composite, nickel reinforced with SiC nanoparticles, was synthesized and characterized for its potential application in next-generation molten salt nuclear reactors. Synchrotron ultra-small-angle X-ray scattering (USAXS) measurements were conducted on the composite. The size distribution and number density of the SiC nanoparticles in the material were obtained through data modelling. Scanning and transmission electron microscopy characterization were performed to substantiate the results of the USAXS measurements. Tensile tests were performed on the samples to measure the change in their yield strength after doping with the nanoparticles. The average interparticle distance was calculated from the USAXS results and is related to the increased yield strength of the composite.

A functional variant of ATG16L2 is associated with Crohn's disease in the Chinese population

AIM

To determine whether genetic polymorphism of the ATG16L2 gene is functionally associated with the incidence of Crohn's disease (CD) in the Chinese population.

METHOD

The single nucleotide polymorphism (SNP) rs11235604 of the ATG16L2 gene was genotyped in 363 patients with CD and 486 healthy volunteers from the Chinese Han population. The distributions of the genotype and allele frequency were compared between patients and controls by the chi-square test. The mRNA expression of ATG16L2 in T cells was evaluated by real-time PCR. Comparisons of mRNA expression of ATG16L2 between patients and controls and between patients with genotype CC and genotype CT/TT were performed with the Student's t-test.

RESULTS

Compared with the controls, patients were found to have a significantly higher proportion of genotype TT (5.5% vs 2.5%, P = 0.04). Allele T was the risk allele for the disease (16.3% vs 12.3%, P = 0.02), with an odds ratio of 1.31 (95% CI 1.04-1.67). The ATG16L2 mRNA of the patients was significantly reduced when compared with the controls (0.0044 ± 0.0018 vs 0.0064 ± 0.0023, P < 0.001). Patients with genotype TT/CT had a significant lower level of ATG16L2 mRNA than patients with genotype CC (0.0036 ± 0.0016 vs 0.0053 ± 0.0028, P = 0.005).

CONCLUSIONS

ATG16L2 is a susceptibility gene for CD in the Chinese population. The rs11235604 SNP is remarkably associated with downregulation of the expression of ATG16L2. Further investigation into the gene's function is warranted for a comprehensive knowledge of the contribution of the variant to the development of CD.

Long noncoding RNA BC032469, a novel competing endogenous RNA, upregulates hTERT expression by sponging miR-1207-5p and promotes proliferation in gastric cancer

Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation and are associated with the development of cancers. To investigate the important role and mechanism of lncRNAs in the progression of gastric cancer, we screened lncRNAs in gastric cancer tissues and corresponding adjacent tissues, and assessed the effects on gastric cancer. Here, we report that BC032469, a novel lncRNA, expressed highly in gastric cancer tissues, and the upregulation was clinically associated with larger tumor size, poor differentiation and shorter survival of gastric cancer patients. Downregulation of BC032469 resulted in a significant inhibition of proliferation in vitro and in vivo. Mechanistically, BC032469 could directly bind to miR-1207-5p and effectively functioned as a sponge for miR-1207-5p to modulate the derepression of hTERT. Thus, BC032469 may function as a ceRNA to impair miR-1207-5p-dependent hTERT downregulation, suggesting that it may be clinically valuable as a poor prognostic biomarker of gastric cancer.

Epidemiology and risk factors for chronic kidney disease in Chinese patients with biopsy-proven lupus nephritis

BACKGROUND

Lupus nephritis (LN) is one of the most serious complications of systemic lupus erythematosus (SLE). It is the most common secondary glomerulonephritis leading to end-stage renal disease.

AIM

The purpose of this study is to evaluate the epidemiology and risk factors of chronic kidney disease (CKD) in Chinese patients with LN.

METHODS

Clinical, laboratory, renal histopathology, treatment and outcome data were collected and retrospectively analysed in LN patients with or without CKD.

RESULTS

At the end of the study, 94 (45.63%) patients were identified as having CKD among 206 individuals with renal biopsy-proven LN. Renal function, represented by serum creatinine and estimated glomerular filtration rate, was significantly decreased in the CKD patients (P = 0.008 and P < 0.001, respectively) at the time of the kidney biopsy. Compared with the non-CKD group, significantly increased proportions of hypertension (P < 0.001), serositis (P = 0.042) and anti-histone antibody positivity (P = 0.004) were detected in the CKD patients. Renal pathological activity and chronicity index scores were significantly increased in the CKD group (P < 0.001 for all). Finally, hypertension (hazard ratio (HR) 2.432, 95% confidence interval (CI) 1.575-3.754, P < 0.001), anti-histone antibody (HR 2.907, 95% CI 1.837-4.600, P < 0.001), and tubular atrophy (HR 1.248, 95% CI 1.007-1.547, P = 0.043) were independent risk factors for CKD.

CONCLUSIONS

Hypertension, anti-histone antibody and tubular atrophy are independent risk factors for CKD in Chinese LN patients.

Antiviral medication use in a cohort of pregnant women during the 2009-2010 influenza pandemic

Preventing influenza-like illness (ILI) during pregnancy with antiviral medication use (AVMU) can mitigate serious health risks to mother and foetus. We report on AVMU in pregnant women in Ontario, Canada, and describe characteristics of AVMU during the 2009-2010 H1N1 pandemic. Rates and risk estimates of AVMU were compared across multiple categories and stratified across ILI infection status. Increased AVMU was observed in women with influenza infections, active smokers, those vaccinated against influenza, and those with pre-existing co-morbidities. Decreased AVMU was observed in women with multiple gestations, and those in neighbourhoods of high immigrant concentrations. Our stratified analysis indicated that the observed patterns differed by ILI infection status. We demonstrated that once infected, women across multiple groups were equally likely to use antiviral medications. In this report we also propose possible clinical explanations for the observed differences in AVMU, which will be useful in planning prevention initiatives for future pandemics.

Third-party tolerogenic dendritic cells reduce allo-reactivity in vitro and ameliorate the severity of acute graft-versus-host disease in allo-bone marrow transplantation

Tolerogenic dendritic cells (tDCs) potently induce and maintain tolerance based on their distinct characteristics compared with conventional DCs. Recent reports show that donor or host tDCs promote allograft survival in mice. In this study, the efficacy of third-party tDCs in the prevention of acute graft-versus-host disease (aGVHD) was evaluated. In vitro, tDCs derived from the bone marrow (BM) of D1 mice were induced by GM-CSF, IL-10 and TGF-β1. The phenotypes, expression of cytokines and suppression of tDCs were analysed. In vivo, the effects of adoptive transfer of third-party-tDCs were evaluated in an MHC-mismatched aGVHD mouse model. Survival, body weight, GVHD scoring, histopathological specimens and serum cytokines were analysed in tDC-treated mice and untreated controls. Tolerogenic DCs had low expression of MHC and co-stimulatory molecules, expressed high levels of 'immunosuppressive' cytokines and suppressed allo-CD4(+) T cell proliferation. In the B6→D2 mouse model, all aGVHD mice died within 18 days. Fortunately, third-party tDCs transferred at low doses (10(4)) effectively prolonged survival after allo-BMT. Furthermore, in the mice treated with 10(4) tDCs, serum levels of IL-10/TGF-β were significantly higher and the percentage of Foxp3(+) cells continually increased compared with the mice treated with other doses of tDCs. Third-party tDCs play a crucial role in reducing the severity of aGVHD by modulating the secretion of various cytokines and expanding Foxp3(+) regulatory T cells, which suggests the possibility of using third-party tDCs for therapeutic applications. Furthermore, special attention should be paid to the optimal range of tDCs for preventing allograft rejection.

miR-1207-5p and miR-1266 suppress gastric cancer growth and invasion by targeting telomerase reverse transcriptase

hTERT is the catalytic subunit of the telomerase complex. Elevated expression of hTERT is associated with the expansion and metastasis of gastric tumor. In this study, we aimed to identify novel tumor suppressor miRNAs that restrain hTERT expression. We began our screen for hTERT-targeting miRNAs with a miRNA microarray. miRNA candidates were further filtered by bioinformatic analysis, general expression pattern in different cell lines, gain-of-function effects on hTERT protein and the potential of these effects to suppress hTERT 3′ untranslated region (3′UTR) luciferase activity. The clinical relevance of two miRNAs (miR-1207-5p and miR-1266) was evaluated by real-time RT-PCR. The effects of these miRNAs on cell growth, cell cycle and invasion of gastric cancer cells were measured with CCK-8, flow cytometry and transwell assays. Finally, the ability of these miRNAs to suppress the transplanted tumors was also investigated. Fourteen miRNAs were identified using a combination of bioinformatics and miRNA microarray analysis. Of these fourteen miRNAs, nine were expressed at significantly lower levels in hTERT-positive cell lines compared with hTERT-negative cell lines and five could downregulate hTERT protein expression. Only miR-1207-5p and miR-1266 interacted with the 3′ UTR of hTERT and the expression levels of these two miRNAs were significantly decreased in gastric cancer tissues. These two miRNAs also inhibited gastric tumor growth in vitro and in vivo. Altogether, miR-1207-5p and miR-1266 were determined to be hTERT suppressors in gastric cancer, and the delivery of these two miRNAs represents a novel therapeutic strategy for gastric cancer treatment.

Carbon nanotube growth for through silicon via application

Through silicon via (TSV) technology is key for next generation three-dimensional integrated circuits, and carbon nanotubes (CNT) provide a promising alternative to metal for filling the TSV. Three catalyst preparation methods for achieving CNT growth from the bottom of the TSV are investigated. Compared with sputtering and evaporation, catalyst deposition using dip-coating in a FeCl2 solution is found to be a more efficient method for realizing a bottom-up filling of the TSV (aspect ratio 5 or 10) with CNT. The CNT bundles grown in 5 min exceed the 50 μm length of the TSV and are multi-wall CNT with three to eight walls. The CNT bundles inside the TSV were electrically characterized by creating a direct contact using a four-point nanoprober setup. A low resistance of the CNT bundle of 69.7 Ω (297 Ω) was measured when the CNT bundle was contacted midway along (over the full length of) the 25 μm deep TSV. The electrical characterization in combination with the good filling of the TSV demonstrates the potential use of CNT in fully integrated TSV applications.

Procoagulant activity of erythrocytes and platelets through phosphatidylserine exposure and microparticles release in patients with nephrotic syndrome

Recent studies showed that an imbalance of prothrombotic and antithrombotic factors and impaired thrombolytic activity contribute to the thrombophilia of the nephrotic syndrome (NS). However, it is not clear whether blood cell injury and/or activation is involved in hypercoagulability in NS patients. Our objectives were to study the increase in microparticle (MP) release and phosphatidylserine (PS) exposure on the outer membrane of MP-origin cells in NS patients, and to evaluate their procoagulant activity (PCA). The subjects were patients with membranous nephropathy (MN), minimal change nephrotic syndrome (MCNS) and healthy controls. Analyses of MPs and PS exposure were performed using a flow cytometer. PCA was determined by clotting time and purified coagulation complex assays. We found that lactadherin+ MPs, which derived from red blood cells (RBC), platelet and endothelial cell, increased in NS patients. Moreover, PS exposure on RBCs and platelets in each NS group, especially in MN, are higher than that in controls. MP shedding and PS exposure of RBCs/platelets were highly procoagulant in NS patients. However, blockade of PS with lactadherin inhibited over 90% of PCA while an anti-tissue factor antibody had no significant inhibition effect. Our results demonstrate that the thrombophilic susceptibility of NS may be partly ascribed to MP release and PS exposure of RBCs, platelets and endothelial cells. Lactadherin is a sensitive probe for PS that has high anticoagulant activity.

Predictors of relapse in chronic hepatitis B after discontinuation of anti-viral therapy

BACKGROUND

Optimal duration of anti-viral therapy in chronic hepatitis B virus (HBV) infection remains unclear.

AIM

To investigate factors that could predict relapse after stopping anti-viral agents.

METHODS

Chronic hepatitis B patients who were treated with anti-viral agents (lamivudine, adefovir, entecavir) and have stopped the treatment were recruited. Anti-viral agents were stopped according to the recommendations of the Asian Pacific Association for the Study of the Liver. Virological relapse was defined as an increase in serum HBV DNA to >1000 copies/mL after discontinuation of treatment.

RESULTS

Eighty-four (69 treatment naïve and 15 lamivudine resistant) patients were eligible for this study. Thirty-seven patients developed virological relapse at 4.3 ± 2.9 (range 1-11) months after discontinuation of therapy. The 1-year cumulative probability of virological relapse was 42% and 47% in HBeAg (hepatitis B e antigen)-positive (n = 41) and HBeAg (hepatitis B e antigen)-negative (n = 43) patients, respectively. On multivariate analysis by Cox proportional hazard model, pre-existing lamivudine resistance, delayed suppression of HBV DNA to undetectable level during anti-viral therapy and to a higher HBsAg (hepatitis B surface antigen) level at the end of treatment were associated with virological relapse. Twelve of the 15 (80%) lamivudine resistant patients developed virological relapse. Among the 11 treatment naïve patients who had HBsAg ≤ 2 log IU/mL at the end of treatment, 1 (9%) of them had virological relapse.

CONCLUSIONS

Treatment cessation among lamivudine resistant patients is associated with high risk of virological relapse. Serum HBsAg level at the end of treatment and rate of HBV DNA suppression can provide supplementary information to guide the timing of stopping anti-viral drugs.

Predictors of relapse in chronic hepatitis B after discontinuation of anti-viral therapy

BACKGROUND

Optimal duration of anti-viral therapy in chronic hepatitis B virus (HBV) infection remains unclear.

AIM

To investigate factors that could predict relapse after stopping anti-viral agents.

METHODS

Chronic hepatitis B patients who were treated with anti-viral agents (lamivudine, adefovir, entecavir) and have stopped the treatment were recruited. Anti-viral agents were stopped according to the recommendations of the Asian Pacific Association for the Study of the Liver. Virological relapse was defined as an increase in serum HBV DNA to >1000 copies/mL after discontinuation of treatment.

RESULTS

Eighty-four (69 treatment naïve and 15 lamivudine resistant) patients were eligible for this study. Thirty-seven patients developed virological relapse at 4.3 ± 2.9 (range 1-11) months after discontinuation of therapy. The 1-year cumulative probability of virological relapse was 42% and 47% in HBeAg (hepatitis B e antigen)-positive (n = 41) and HBeAg (hepatitis B e antigen)-negative (n = 43) patients, respectively. On multivariate analysis by Cox proportional hazard model, pre-existing lamivudine resistance, delayed suppression of HBV DNA to undetectable level during anti-viral therapy and to a higher HBsAg (hepatitis B surface antigen) level at the end of treatment were associated with virological relapse. Twelve of the 15 (80%) lamivudine resistant patients developed virological relapse. Among the 11 treatment naïve patients who had HBsAg ≤ 2 log IU/mL at the end of treatment, 1 (9%) of them had virological relapse.

CONCLUSIONS

Treatment cessation among lamivudine resistant patients is associated with high risk of virological relapse. Serum HBsAg level at the end of treatment and rate of HBV DNA suppression can provide supplementary information to guide the timing of stopping anti-viral drugs.

Orthodontic force stimulates eNOS and iNOS in rat osteocytes

Mechanosensitive osteocytes are essential for bone remodeling. Nitric oxide, an important regulator of bone remodeling, is produced by osteocytes through the activity of constitutive endothelial nitric oxide synthase (eNOS) or inducible nitric oxide synthase (iNOS). We hypothesized that these enzymes regulate the tissue response to orthodontic force, and therefore we investigated eNOS and iNOS expression in osteocytes during orthodontic force application. The upper rat molars were moved mesially by NiTi coil springs (10 cN, 120 hrs) in a split-mouth design. Immunohistochemical staining revealed that, in the tension area, eNOS-positive osteocytes increased from 24 hrs on, while iNOS-positive osteocytes remained largely constant. In the compression area, iNOS-positive osteocytes increased after 6 hrs, while eNOS- positive osteocytes increased after 24 hrs. This suggests that eNOS mediates bone formation in the tension area, while iNOS mediates inflammation-induced bone resorption in the compression area. Both eNOS and iNOS seem to be important regulators of bone remodeling during orthodontic force application.

Advanced malignant pleural or peritoneal effusion in patients treated with recombinant adenovirus p53 injection plus cisplatin

The aim of this study was to evaluate the efficacy of recombinant adenovirus p53 agent (rAd-p53) injection combined with cisplatin (CDDP) for the treatment of malignant pleural or peritoneal effusion. After puncture drainage, patients in the treatment group (n = 27) received intracavitary administration of rAd-p53 (2 x 10(12) virus particles) once a week for 4 weeks. At 48 h after each rAd-p53 injection, patients were given intracavitary administration of cisplatin 60 mg/m(2). This administration procedure continued once a week for 4 weeks. The control group (n = 21) received the same intracavitary therapy as the treatment group but without rAd-p53 therapy. Efficacy was evaluated by clinical observations, computed tomography, tumour markers, Karnofsky score and short-term follow-up. The total effective rates for the treatment group (63.0%) were significantly higher than for the control group (42.9%), suggesting that the treatment group benefited over the control group. In conclusion, rAd-p53 therapy is a safe and effective treatment for advanced malignant pleural or peritoneal effusion.

Rat Parathyroid Hormone 1 − 34 Signals through the MEK/ERK Pathway to Induce Cardiac Hypertrophy

This study aimed to characterize the role of the mitogen-activated protein kinase (MAPK) kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway in cardiac hypertrophy induced by parathyroid hormone (PTH). Various concentrations of rat PTH1–34 were used to induce hypertrophy in neonatal rat ventricular cardiomyocytes, and the effects were compared with control cells and those treated with PD98059, a selective inhibitor of MEK1. Hypertrophy was assessed in terms of cell diameter, atrial natriuretic peptide (ANP) mRNA expression and protein synthesis; the MEK/ERK pathway was assessed by measuring levels of phosphorylated ERK1/2. Treatment with PTH1–34 at 100 nM for 24 h effectively induced cardiac hypertrophy (increased cell diameter, protein synthesis and ANP mRNA expression) and also increased levels of phosphorylated ERK1/2 compared with normal control cells. Treatment with PTH1–34 plus PD98059 significantly attenuated these changes. These results demonstrate that inhibition of the MEK/ERK pathway blocks PTH1–34-induced cardiac hypertrophy, suggesting that PTH1–34 might signal through the MAPK pathway to induce hypertrophy in cardiomyocytes.

Whole cell recordings of intrinsic properties and sound-evoked responses from the inferior colliculus

Response features of inferior colliculus (IC) neurons to both current injections and tone bursts were studied with in vivo whole cell recordings in awake Mexican free-tailed bats. Of 160 cells recorded, 95% displayed one of three general types of discharge patterns in response to the injection of positive current: 1) sustained discharges; 2) adapting discharges; and 3) onset-bursting discharges. Sustained neurons were the most common type (N=78), followed by onset-bursting (N=57). The least common type was adapting (N=17). In 90 neurons the profiles of synaptic and discharge activity evoked by tones of different frequencies at 50 dB SPL were recorded. Three major tone-evoked response profiles were obtained; 1) neurons dominated by excitation (N=32) in which tones evoked excitatory post-synaptic potentials (EPSPs) or EPSPs with discharges over a range of frequencies with little or no evidence of inhibitory post-synaptic potentials (IPSPs) evoked by frequencies that flanked the excitation; 2) neurons that had an excitatory frequency region in which discharges were evoked that was flanked by frequencies that evoked predominantly IPSPs (N=26); 3) neurons in which all frequencies evoked IPSPs with little or no depolarizations (N=32). The question we asked is whether IC cells that express a particular profile of PSPs and discharges to acoustic stimulation also have the same current-evoked response profile. We show that, with one exception, the intrinsic features of an IC neuron are not correlated with the pattern of its synaptic innervation; the two features are unrelated in the majority of IC cells. The exception is a subtype of inhibitory dominated cell where most frequencies evoked IPSPs to both the onset and to the offset of the tone bursts. In those cells injected current steps always evoked an onset-bursting response.

Phase I and pharmacokinetic study of irinotecan in combination with R115777, a farnesyl protein transferase inhibitor

The aims of this study were to determine the maximum-tolerated dose (MTD), toxicity profile, and pharmacokinetics of irinotecan given with oral R115777 (tipifarnib), a farnesyl protein transferase inhibitor. Patients were treated with escalating doses of irinotecan with interval-modulated dosing of R115777 (continuously or on days 1–14, and repeated every 21 days). In total, 35 patients were entered onto the trial for a median duration of treatment of 43 days (range, 5–224 days). Neutropenia and thrombocytopenia were the dose-limiting toxicities; other side effects were mostly mild. The MTD was established at R115777 300 mg b.i.d. for 14 consecutive days with irinotecan 350 mg m⁻² given every 3 weeks starting on day 1. Three patients had a partial response and 14 had stable disease. In the continuous schedule, the area under the curves of irinotecan and its active metabolite SN-38 were 20.0% (P=0.004) and 38.0% (P<0.001) increased by R115777, respectively. Intermittent dosing of R115777 at a dose of 300 mg b.i.d. for 14 days every 3 weeks is the recommended dose of R115777 in combination with the recommended single-agent irinotecan dose of 350 mg m⁻².

Benzodioxocin-3-ones and N-acyl-3-amino-3-buten-2-ones: novel classes of cathepsin K cysteine protease inhibitors

The design, synthesis, enzymologic, and protein mass spectrometric characterization of benzodioxocin-3-one and N-acyl-3-amino-3-buten-2-one inhibitors of the cysteine protease cathepsin K are described. The benzodioxocin-3-one ring system is chemically unstable giving rise to a mixture of N-acyl-3-amino-3-buten-2-one and hemiketals. This mixture of N-acyl-3-amino-3-buten-2-one and hemiketals potently inhibits recombinant, human cathepsin K (IC50 = 36 nM) by a time-independent, irreversible mechanism. Formation of a covalent adduct between cathepsin K and inhibitor has been confirmed by mass spectrometry.

Highly toxic and broad-spectrum insecticidal Bacillus thuringiensis engineered by using the transposon Tn917 and protoplast fusion

The chromosome of the Bacillus thuringiensis strain S184 that was toxic against the third instar larvae of Spodoptera litura with the LC(50) of 9.74 microg/ml was successfully integrated into two genes of cyt1Aa and cry11Aa using the transposon Tn917, yielding the primary engineered strain TnX. The strain TnX was highly toxic to the third instar larvae of Culex pipiens fatigans with the LC(50) of 5.12 ng/ml which was 1.82-fold higher than that of B. thuringiensis subsp. israelensis, but lowly toxic to lepidopterous larvae. By the protoplast fusion of the strain TnX and the strain S184-Tet(r) (resistance to tetracycline), the target engineered strain TnY was obtained. Against the third instar larvae of S. litura, the strain TnY LC(50) was of 4.68 micro g/ml and increased by 2.08-fold in comparison with the parent strain S184. Against the third instar larvae of C. pipiens fatigans, the strain TnY LC(50) was of 103.20 ng/ml. The two target genes of cyt1Aa and cry11Aa integrated into the chromosome were extremely stable and had little possibility of a second transposition. It was unclear whether some factors existing in the parent strain, S184, contributed to the high toxicity of the strains TnX and TnY.

The cell cycle control element of histone H4 gene transcription is maximally responsive to interferon regulatory factor pairs IRF-1/IRF-3 and IRF-1/IRF-7

Interferon regulatory factors (IRFs) are transcriptional mediators of interferon-responsive signaling pathways that are involved in antiviral defense, immune response, and cell growth regulation. To investigate the role of IRF proteins in the regulation of histone H4 gene transcription, we compared the transcriptional contributions of IRF-1, IRF-2, IRF-3, and IRF-7 using transient transfection assays with H4 promoter/luciferase (Luc) reporter genes. These IRF proteins up-regulate reporter gene expression but IRF-1, IRF-3, and IRF-7 are more potent activators of the H4 promoter than IRF-2. Forced expression of different IRF combinations reveals that IRF-2 reduces IRF-1 or IRF-3 dependent activation, but does not affect IRF-7 function. Thus, IRF-2 may have a dual function in histone H4 gene transcription by acting as a weak activator at low dosage and a competitive inhibitor of other strongly activating IRFs at high levels. IRF-1/IRF-3 and IRF-1/IRF-7 pairs each mediate the highest levels of site II-dependent promoter activity and can up-regulate transcription by 120-150-fold. We also find that interferon gamma up-regulates IRF-1 and site II-dependent promoter activity. This up-regulation is not observed when the IRF site is mutated or if cells are preloaded with IRF-1. Our results indicate that IRF-1, IRF-2, IRF-3, and IRF-7 can all regulate histone H4 gene expression. The pairwise utilization of distinct IRF factors provides a flexible transcriptional mechanism for integration of diverse growth-related signaling pathways.

[AFLP markers of restoring genes of the wild-abortive hybrid rice]

Fertile and sterile pools were set up by bulked segregant analysis (BSA) based on the selection for the highly fertile and highly sterile plants of Shanyou 63 F2 population. The AFLP analysis of the two pools indicated that 64 primer combinations amplified 3,477 stable and clear bands. Exception of the combination E-AGC/M-CAA, all primer combinations had not detected polymorphism between the two pools. It was proved by investigation of two parents, individuals of F2 segregant population, backbone sterile lines and restorer lines that the polymorphic fragment AP1 generated from the primer E-AGC/M-CAA was associated with the restoring gene. AP1 was a single copy detected by Southern blot hybridization. The distance between AP1 and the restoring gene was 4.76 cM.

[Detection of viral aetiology in cerebral spinal fluid samples from 580 clinical cases]

OBJECTIVE

To investigate the viral aetiology in cerebral spinal fluid (Csf) from 580 cases of CNS infection or FUO in Yuedong district from 1990 to 1997.

METHODS

Virus isolation was done with Hep-2 and BHK-21 cells.

RESULTS

21 virus types of 5 kinds of viruses were isolated from 113 samples (19.5%). Clinically diagnosed diseases included viral encephalitis 17.8% (43/242), intracranial infection 20.2% (47/233), paralytic diseases 24.3% (9/37), FUO 37.5% (9/24), convulsion 16.0% (4/25), Guillain-Barre syndrome 5.3% (1/19). Virus infection included 11 cases of Poliovirus (constitutional ratio 0.0973, including 1 Polio-I, 8 Polio-II, 2 Polio-III); 54 cases of Coxsackie virus (0.477 9, including 11 CoxA24, 10 CoxBl, 2 Cox134, 3 CoxB5); 15 cases of ECHO virus (0.1327, including 4 ECHO-24, 3 ECRO-7, 2 ECHO-12 and each one of ECHO-3, 11,14,15,27,32); 25 cases of Enterovirus (0.2213, including 14 EV-70, 11 EV-71); 8 cases of Adenovirus (0.070 8, including 3 Adv-2, 3 Adv-3 and 2 Adv7). Results of different age groups indicated there was significant difference (P < 0.05) in virus detection rate in two age groups. Virus positive rates in different years were 1990-1991 14.2% (15/106), 1992-1993 14.1%(23/163), 1994-1995 26.1% (36/138), 1996-1997 22.5% (39/173), that showed a significant difference (P <0.05).

CONCLUSIONS

Virus infection rate of CNS diseases and FUO showed an a ascending trend, and the different virus types and kinds were isolated in different periods.

[Insulin secretion and resistance during pregnancy in women with glucose intolerance]

OBJECTIVE

To investigate whether insulin secretion and resistance are different in glucose tolerant and intolerant women with normal pre-pregnant body mass index (BMI) during late pregnancy and to find out if there is association between gestational diabetes and insulin resistance syndrome.

METHODS

On the basis of a 4-hour oral glucose tolerance test (OGTT), 32 gestational diabetes mellitus (GDM) patients, 21 gestational impaired glucose tolerant (GIGT) patients, and 50 normal glucose tolerant (NGT) cases were selected from uncomplicated pregnant women. Those had normal pre-pregnant BMI who had a 1-hour 50-g glucose-screening test (> or = 7.2 mmol/L), performed between 24-28 weeks of gestation. During the OGTT, several indexes of insulin resistance, insulin secretion, lipid metabolism were measured in addition to the standard glucose measurements.

RESULTS

Glucose area under curve (GAUC), insulin area under curve (IAUC), insulin sensitivity index (ISI) transformed to natural logarithm and triglycerides (TG) are all significantly higher (P < 0.05) in GDM women. The means of these indexes in GDM group are 26.3 mmol/L.h-1, 276.5 mU/L.h-1, 4.2 and 3.2 mmol/L, respeetively. On the other hand, however, the differences of these indexes (except TG) between GIGT and NGT women are not statistically significant. The ratio of IAUC/GAUC has an increasing trend from GDM group, GIGT group to NGT group (10.5, 11.4 and 11.7, respectively), but the difference is not statistically significant. Multiple correlation coefficient study demonstrated that ISI is significantly positively correlated with GAUC, IAUC and TG (P < 0.01).

CONCLUSIONS

Compared with NGT women, GDM women has impaired insulin secretion, abnormally increased insulin resistance, and relatively dyslipidemia. GDM seems to be a component of the syndrome of insulin resistance that provides an excellent model for study and prevention in a relatively young aged group.

Effects of a calcimimetic compound and naturally activating mutations on the human Ca2+ receptor and on Ca2+ receptor/metabotropic glutamate chimeric receptors

Naturally occurring mutations identified in subjects with autosomal dominant hypocalcemia (ADH) and the calcimimetic compound, R-568, have both been reported to increase Ca2+ sensitivity of the Ca2+ receptor (CaR). To gain insight into their mechanism of action, we studied interactions between four different ADH mutations located in the amino-terminal extracellular domain (ECD) and R-568. We found that R-568 increased the sensitivity of three of the ADH mutant receptors, but the Leu125Pro mutant appeared to be maximally left-shifted in that neither R-568 addition nor combining other ADH mutations with Leu125Pro gave increases in sensitivity comparable to those seen with the three other ADH mutations studied. We also made use of truncation and deletion mutants of the CaR and CaR/metabotropic glutamate receptor type 1 (mGluR1) chimeras to study both the site of action of R-568 and the effect of the Leu125Pro activating mutation. R-568 was effective in receptor constructs containing the seven transmembrane domain (7TM) of the CaR, but not in those containing the mGluR1 7TM. R-568, moreover, imparted Ca2+ responsiveness to CaR constructs lacking all or part of the CaR ECD. The Leu125Pro mutation in contrast conferred no or minimal increase in Ca2+ responsiveness to CaR constructs lacking part of the CaR ECD but showed a striking increase in basal activity in the context of chimeras containing an mGluR1 7TM. Our results localize the site of action of NPS-568 specifically to the CaR 7TM. Our results with the Leu125Pro mutant, furthermore, suggest that the mGluR1 7TM domain may be more permissive for activation than the 7TM domain of the CaR.

A novel pharmacological approach to treating cardiac ischemia. Binary conjugates of A1 and A3 adenosine receptor agonists

Adenosine released during cardiac ischemia exerts a potent, protective effect in the heart via activation of A(1) or A(3) receptors. However, the interaction between the two cardioprotective adenosine receptors and the question of which receptor is the more important anti-ischemic receptor remain largely unexplored. The objective of this study was to test the hypothesis that activation of both receptors exerted a cardioprotective effect that was significantly greater than activation of either receptor individually. This was accomplished by using a novel design in which new binary conjugates of adenosine A(1) and A(3) receptor agonists were synthesized and tested in a novel cardiac myocyte model of adenosine-elicited cardioprotection. Binary drugs having mixed selectivity for both A(1) and A(3) receptors were created through the covalent linking of functionalized congeners of adenosine agonists, each being selective for either the A(1) or A(3) receptor subtype. MRS 1740 and MRS 1741, thiourea-linked, regioisomers of a binary conjugate, were highly potent and selective in radioligand binding assays for A(1) and A(3) receptors (K(i) values of 0.7-3.5 nm) versus A(2A) receptors. The myocyte models utilized cultured chick embryo cells, either ventricular cells expressing native adenosine A(1) and A(3) receptors, or engineered atrial cells, in which either human A(3) receptors alone or both human A(1) and A(3) receptors were expressed. The binary agonist MRS 1741 coactivated A(1) and A(3) receptors simultaneously, with full cardioprotection (EC(50) approximately 0.1 nm) dependent on expression of both receptors. Thus, co-activation of both adenosine A(1) and A(3) receptors by the binary A(1)/A(3) agonists represents a novel general cardioprotective approach for the treatment of myocardial ischemia.

[Establishment and application of Z-HL16C cell line]

OBJECTIVE

Human embryonic lung fibroblasts at 8th passage was presented to us by the Institute of Virology. At its 16th passage,under the culture condition of our laboratory, the lung fibroblasts changed into epithelial like cells. We attempted to establish a cell line and applied it for virus isolation.

METHODS

The cells were continuously passaged, cloned, the cell morphology, growth capacity and chromosome number were determined.

RESULTS

The cell size appeared uniform, cell boundary was distinct, the cell recovery rate after frozen storing was above 90%. The cell replicated permanently and now it has been passaged 136 times. The chromosome number has changed from 46 to 110. We named this cell line the ZHL16C. It proved to be sensitive to these viruses tested: enteroviruses (Polio, Cox, Echo), influenza viruses, parainfluenza viruses, adenoviruses, measles virus, herpes simplex and herpes zoster viruses, cytomegalovirus, rubella virus and respiratory syncytial virus. When using Z-HL16C cell to isolate virus from 29 adenovirus swab samples collected from 29 soldiers with epidemic high fever in a new military, adenovirus type 3,7 coxsackie virus types B1, B5, B5, B5, B5 were isolated.

CONCLUSIONS

The cell line HL16C has been stably established, it has a broad spectrum in sensitivity for viruses.

Generation of the enol of methyl mandelate by flash photolysis of methyl phenyldiazoacetate in aqueous solution and study of rates of ketonization of this enol in that medium

Flash photolysis of methyl phenyldiazoacetate in aqueous solution produced phenylcarbomethoxycarbene, whose hydration generated a short-lived transient species that was identified as the enol isomer of methyl mandelate. This assignment is supported by the shape of the rate profile for decay of the enol transient, through ketonization to its carbonyl isomer, as well as by solvent isotope effects and the form of acid-base catalysis of the ketonization reaction. Comparison of the present results with previously published information on the enol of mandelic acid shows some interesting and readily understandable similarities and differences.

Selective A(3) adenosine receptor antagonists: water-soluble 3, 5-diacyl-1,2,4-trialkylpyridinium salts and their oxidative generation from dihydropyridine precursors

A(3) adenosine receptor antagonists are sought for their potential antiinflammatory, antiasthmatic, and antiischemic properties. We have found that 3,5-diacyl-1,2,4-trialkyl-6-phenylpyridinium derivatives constitute a novel class of selective A(3) adenosine receptor antagonists. The structure-activity relationships of this class of antagonists, incorporating the 3-thioester, have been explored. The most potent analogue in this group was 2, 4-diethyl-1-methyl-3-(ethylsulfanylcarbonyl)-5-ethyloxycarbonyl -6-phe nylpyridinium iodide (11), which had an equilibrium inhibition constant (K(i)) value of 219 nM at human A(3) receptors (binding of [(125)I]AB-MECA (N(6)-(4-amino-3-iodobenzyl)-5'-N-methylcarbamoyladenosine)) expressed in Chinese hamster ovary (CHO) cells and >10 microM at rat brain A(1) and A(2A) receptors and at recombinant human A(2B) receptors. Compound 11 could be generated through oxidation of the corresponding 3,5-diacyl-1,2,4-trialkyl-6-phenyl-1,4-dihydropyridine, 24, with iodine or in the presence of rat brain homogenates. A 6-cyclopentyl analogue was shown to increase affinity at human A(3) receptors upon oxidation from the 1-methyl-1,4-dihydropyridine analogue, 25, to the corresponding pyridinium derivative, 23 (K(i) 695 nM), suggesting a prodrug scheme. Homologation of the N-methylpyridinium derivatives to N-ethyl and N-propyl at the 1-position caused a progressive reduction in the affinity at A(3) receptors. Modifications of the alkyl groups at the 2-, 3-, 4-, and 5-positions failed to improve potency in binding at A(3) receptors. The pyridinium antagonists are not as potent as other recently reported, selective A(3) receptor antagonists; however, they display uniquely high water solubility (43 mM for 11). Compound 11 antagonized the inhibition of adenylate cyclase elicited by IB-MECA in CHO cells expressing the human A(3) adenosine receptor, with a K(B) value of 399 nM, and did not act as an agonist, demonstrating that the pyridinium salts are pure antagonists.

[Effects of yi qi tong mai oral liquid on acute myocardial ischemia in dogs]

The objective of this study was to assess the prophylactic and therapeutic effects of Yi Qi Tong Mai Oral Liquid (YQTMOL) on acute myocardial ischemia. The models of ischemia were made, in which the anterior coronary arteries of anesthetized dogs were ligated. Four groups of dogs were examined and compared. We determined the extent of their myocardial ischemia and infarction by means of epicardial mapping and N-BT staining. The results showed that in the treatment groups, the increase of sigma-ST was inhibited 30-180 minutes after the oral administration of YQTMOL(compared with control group, P < 0.01), and the sigma-ST was decreased (P < 0.05). Furthermore, in the group dosed with YQTMOL (10 g/kg), the ratios of "area of infarction/heart weight" and "area of infarction/ventricle weight" both decreased (compared with control group, P < 0.05). These findings indicated that YQTMOL reduced the area of myocardial ischemia and the degree of myocardial infarction in dogs, so it could be effective for the prevention and treatment of acute myocardial ischemia.

[CT in diagnosis of tuberculosis of liver and spleen]

OBJECTIVE

To analyze CT findings of hepatospleeno-tuberculosis and to explore the characteristics for diagnosis and differential diagnosis of the disease.

METHODS

CT scans were performed in fifteen patients. There were nine men and six women, the age ranging from 18 to 60 years old. All patients were diagnosed clinically, one of which was confirmed by pathology after surgery, two of which were confirmed by pathology through CT-guided biopsy.

RESULTS

All cases were concurrent with two or more other tuberculosis. Disseminated milliary, small nodules and small saccular foci were present in livers of 8 cases and spleens of 5, and isolated low dense lesion in liver of 1 case, diffuse calcifications in liver and spleen of another 1.

CONCLUSIONS

When disseminated milliary, small nodules and small saccular foci are found by CT in liver or spleen and tuberculous lesions are present in other tissues, diagnosis of liver and/or spleen tuberculosis should be considered.

[CT images in differentiating tuberculous nodules from lung cancers with diameters less than 2 cm]

OBJECTIVE

To find out the CT characteristics of tuberculous nodules and lung cancers with diameters less than 2 cm, and to evaluate their value in differentiating the two diseases.

METHOD

The CT images in thirty patients with tuberculous nodules and forty lung cancer patients with lesions less than 2 cm in diameter were compared.

RESULTS

Smooth or clear edge, non-lobulation, small cavity, calcification, pleural thicking and adhesion, satellitic nidus and perifocal inflammation were found predominant in tuberculous nodules with short-term dynamic changes in shapes, while shaggy border, shallow lobulation, vacuolus sign, air-bronchogram and typical pleural indentation were predominant in lung cancers without dynamic changes in shapes.

CONCLUSION

Thin-slice CT scanning can provide useful images, which by short-term observations are important for differentiating these diseases.

Blood-brain barrier equilibration of codeine in rats studied with microdialysis

PURPOSE

The purpose of the study was to investigate the distribution of codeine across the blood-brain barrier (BBB) in rats by microdialysis (MD).

METHODS

Rats were administered intravenous infusion of codeine in doses of (1) 10 mg/kg, (2) 20 mg/kg for 10 min, and (3) an exponential infusion for 2 h aiming at a plasma concentration of 2500 ng/ml, in a crossover design (n = 6). Microdialysis was used to determine codeine unbound concentrations in blood and brain extracellular fluid (ECF). Total brain tissue and plasma concentrations were also determined. Nalorphine was used as a calibrator for measurement of in vivo recovery.

RESULTS

Relative recovery and retrodialysis loss of codeine and nalorphine were similar both in vitro and in vivo. Codeine was rapidly transported into the brain ECF with identical influx and efflux clearance across the BBB. The AUC ratios of brain to blood were 0.99 +/- 0.25 and 0.95 +/- 0.16 for Dose 1 and 2, respectively. The Css ratio of brain to blood was 1.06 +/- 0.12 for the exponential infusion. The half-lives were 25 +/- 4 min, 22 +/- 2 min in blood and 27 +/- 5 min, 25 +/- 5 min in brain for Dose 1 and Dose 2, respectively. Total brain tissue concentrations were 3.6 +/- 1.2-fold higher than the unbound concentrations in brain. Codeine was demethylated to morphine with an unbound AUCblood,morphine/AUCblood,codeine ratio of 7.7 +/- 5.1% in blood. No morphine was detected in brain MD, but total concentrations were possible to measure.

CONCLUSIONS

Codeine rapidly reached a distributional equilibrium with equal unbound concentrations in blood and brain. The brain transport of codeine did not show any dose-dependency.

[Extraction, purification and ascertainment of anti-hepatoma active principles for targeted preparation of radix Aconiti Kusnezoffii]

The extraction, purification, pharmacological experiments and chemical analysis of anti-hepatoma active principles of Radix Aconiti Kusnezoffii have been studied. The results show that the medicinal material Radix Aconiti Kusnezoffii is efficacious in inhibiting hepatoma, and the active principles are mainly made up of poisonous ester alkaloids. The liver targeting delivery system will be the first choice for its anti-hepatoma preparation, and the effective component AY3a is fit for the preparation of targeted microspheres.

[Study on enterovirus aetiology of CNS infection in Shantou]

Enterovirus isolation and serological assay were done in 236 cases of CNS infection in Shantou. 62 strains of virus (from 55 cases) were isolated from 257 samples of 236 cases (24.1%). 48 cases were positive among 57 cases (84.2%) by serological assay. 78 cases were positive for virus isolation and/or serological assay (33.1%). Virus infection included 33 cases of poliovirus (including 6 polio-I, 18 polio-II, 4 polio-III, 5 mixed infections), 21 cases of Coxsackie virus (including 6 CoxA24,7 CoxB1,2 CoxB4 and 6 CoxB5), 11 cases of ECHO virus (including 5 ECHO-7,2 ECHO-24 and each one of ECHO-11, 12, 15, 27), 10 cases of Enterovirus (including 3 EV-70, 7 EV-71), and 3 cases of mixed viral infection.

Nonhistone protein reorganization in normal and hepatoma cells

Previously we described (Dong et al., 1990) a nuclear protein (mol. wt. 112 kD) which is expressed abundantly in hepatoma cells and also in hepatocyte cells committed to carcinogenesis. In this report, we further characterize its chemical properties and cellular localization in normal and hepatoma cells. 112 kD hepatoma-associate nonhistone protein is not a cytokeratin-related protein as described by Fukuda et al. (1991). Protein purification experiments revealed that 112 kD protein is a dimer of 56 kD polypeptide present in normal rat liver nuclei. Intranuclear distribution pattern indicated that 112 kD nonhistone protein localizes exclusively in hepatoma nuclear matrix. The data from this study suggest that dimerization of 56 kD nonhistone protein is involved in nuclear matrix reorganization during neoplastic transformation.

Glucocorticoids coordinately regulate type I collagen pro alpha 1 promoter activity through both the glucocorticoid and transforming growth factor beta response elements: a novel mechanism of glucocorticoid regulation of eukaryotic genes

Glucocorticoids have previously have shown to decrease Type I collagen synthesis in vivo and in fibroblast cell culture. Several studies have demonstrated that glucocorticoids decrease Type I procollagen gene expression. These latter studies have included uridine incorporation into pro alpha 1 (I) and pro alpha 2 (I) mRNAs and nuclear run-off experiments. Using the ColCat 3.6 plasmid, which contains part of the 5' flanking region of the pro alpha 1 (I) collagen gene and the reporter gene, chloramphenicol acetyltransferase, the present studies demonstrate by stable transfection of fetal rat skin fibroblasts that dexamethasone down regulates the promoter activity of the pro alpha 1 (I) collagen gene. The glucocorticoid-mediated down-regulation of procollagen gene expression was demonstrated using the ColCat 3.6, 2.4, 1.7, or 0.9 plasmid. In addition, competitive oligonucleotide transfection experiments and site specific mutation of the glucocorticoid response element (GRE) in the whole ColCat 3.6 plasmid did not eliminate the effect. The possibility existed that another cis-element in the 5' flanking region of the pro alpha 1 (I) collagen gene was also required for the collagen glucocorticoid-mediated down-regulation of procollagen gene expression, since TGF-beta has been shown to stimulate in a decrease of transforming growth factor-beta (TGF-beta) secretion into the media. Gel mobility studies demonstrated that glucocorticoid treatment of rat skin fibroblasts decreased glucocorticoid receptor binding to the GRE and TGF-beta activator protein to the TGF-beta element which were brought back to control values by coordinate exogenous TGF-beta treatment. Thus the interaction of these TGF-beta molecules with cellular membrane receptors and subsequent transduction is dramatically decreased resulting in less signals to regulate collagen gene expression. These data indicate that glucocorticoids coordinately regulate procollagen gene expression through both the GRE and TGF-beta elements. Depression of procollagen gene expression by glucocorticoids through the TGF-beta element is mediated by decreased TGF-beta secretion, possibly involving a secondary effect on regulatory protein(s) encoded by noncollagenous protein gene(s). The present studies provide the basis for a novel mechanism of glucocorticoid-mediator regulation of eukaryotic genes containing the TGF-beta element.

An activated mutant of the alpha subunit of G(o) increases neurite outgrowth via protein kinase C

The GTP-binding protein, G(o), is present at very high concentration in the neuronal growth cone membrane. The expression of activated mutants of the a subunit of G(o) increases neurite outgrowth. To determine the intracellular mechanism for this outgrowth, we have examined activated alpha o-dependent outgrowth in the presence of agents which modulate different signal transduction cascades. Activation of protein kinase C with phorbol esters or with diacylglycerol prevents the alpha o-dependent increase in neurite extension. Inhibition of protein kinase C with staurosporine, with H7, or with long-term, high dose phorbol ester treatment resulted in greater neurite elongation, and no further increase after activated alpha o transfection. The protein phosphatase inhibitor, okadaic acid, also blocked the effect of activated alpha o. In contrast, tyrosine kinase inhibitors and agents which alter cAMP levels did not alter activated alpha o-dependent neurite extension. We tested a number of compounds which alter intracellular calcium levels. TMB-8 and thapsigargin prevented an increase in outgrowth by activated alpha o, but diltiazem, Bay K8644 and dantrolene had no effect on activated alpha o-dependent outgrowth. These studies suggest that activated alpha o increases neurite outgrowth by inhibiting protein kinase C and by modulating intracellular calcium release.