Involvement of ERK1/2 signaling in proliferation of eight liver cell types during hepatic regeneration in rats

It has been well established that ERK1/2 signaling, often subdivided into nine types of pathways, can regulate the hepatocyte proliferative response during liver regeneration. However, the effect of ERK1/2 signaling on the proliferation of other hepatic cell types remains unclear. We isolated and purified 8 liver cell types at 10 time points after 2/3 hepatectomy in adult rats. For each cell type, mRNA expression changes for ERK1/2 signaling-involved genes were monitored up to 168 h, using microarrays. Real-time PCR assays were performed for array data verification. The expression levels of these genes varied considerably between different cell types. Integrating microarray results with gene synergical analysis, at the priming phase, activation of integrin/Grb2/Ras pathway in hepatocytes apparently contributed to G0/G1 transition. Two other pathways, G-protein/EPAC/Rap1 and G-protein/PKA/Rap1, were stimulated in hepatic stellate cells, while RTK/PKC/Ras and RTK/Grb2/Ras were stimulated in Kupffer cells. At the progressive phase, the ERK1/2 pathway is involved in hepatocyte replication; three pathways, namely Ca(2+)/PKC/Ras, RTK/Grb2/Ras and G-protein/EPAC/Rap1, were found to play roles in biliary epithelial cell proliferation, while RTK/PKC/Ras and RTK/Grb2/Ras were involved in Kupffer cell proliferation, and G-protein/PKC/Ras in pit cell proliferation. At the terminal phase, the promotive effect of the ERK1/2 pathway on replication of hepatocytes, biliary epithelial cells, oval cells, hepatic stellate cells, Kupffer cells, and dendritic cells was considerably reduced, possibly due to their differentiation at the end of regeneration. G-protein/PKC/Ras, integrin/Grb2/Ras and G-protein/ PKA/Rap1 pathways were active in sinusoidal endothelial cells, perhaps to aid in their proliferation. We conclude that ERK1/2 has a signaling role in the regulation of proliferation of 8 cell types during liver regeneration process.

Characterization of the interaction between astrocytes and encephalitogenic lymphocytes during the development of experimental autoimmune encephalitomyelitis (EAE) in mice

The nature of pathogenic mechanisms associated with the development of multiple sclerosis (MS) have long been debated. However, limited research was conducted to define the interplay between infiltrating lymphocytes and resident cells of the central nervous system (CNS). Data presented in this report describe a novel role for astrocyte-mediated alterations to myelin oligodendrocyte glycoprotein (MOG)(35-55) -specific lymphocyte responses, elicited during the development of experimental autoimmune encephalitomyelitis (EAE). In-vitro studies demonstrated that astrocytes inhibited the proliferation and interferon (IFN)-γ, interleukin (IL)-4, IL-17 and transforming growth factor (TGF)-β secretion levels of MOG(35-55) -specific lymphocytes, an effect that could be ameliorated by astrocyte IL-27 neutralization. However, when astrocytes were pretreated with IFN-γ, they could promote the proliferation and secretion levels of MOG(35-55) -specific lymphocytes, coinciding with apparent expression of major histocompatibility complex (MHC)-II on astrocytes themselves. Quantitative polymerase chain reaction (qPCR) demonstrated that production of IL-27 in the spinal cord was at its highest during the initial phases. Conversely, production of IFN-γ in the spinal cord was highest during the peak phase. Quantitative analysis of MHC-II expression in the spinal cord showed that there was a positive correlation between MHC-II expression and IFN-γ production. In addition, astrocyte MHC-II expression levels correlated positively with IFN-γ production in the spinal cord. These findings suggested that astrocytes might function as both inhibitors and promoters of EAE. Astrocytes prevented MOG(35-55) -specific lymphocyte function by secreting IL-27 during the initial phases of EAE. Then, in the presence of higher IFN-γ levels in the spinal cord, astrocytes were converted into antigen-presenting cells. This conversion might promote the progression of pathological damage and result in a peak of EAE severity.

First Report of Tomato yellow leaf curl virus Infecting Common Bean in China

Common bean (Phaseolus vulgaris) is one of the most economically important vegetable crops in China. In November 2011, symptoms with thickening and crumpling of leaves and stunting were observed on common bean with incidence rate of 50 to 70% in the fields of Huaibei, northern Anhui Province, China. Diseased common bean plants were found to be infested with large population of whiteflies (Bemisia tabaci), which induced leaf crumple symptoms in healthy common beans, suggesting begomovirus etiology. To identify possible begomoviruses, 43 symptomatic leaf samples from nine fields were collected and total DNA of each sample was extracted. PCR was performed using degenerate primers PA and PB to amplify a specific region covering AV2 gene of DNA-A and part of the adjacent intergenic region (2). DNA fragments were successfully amplified from 37 out of 43 samples and PCR amplicons of 31 samples were used for sequencing. Sequence alignments among them showed that the nucleotide sequence identity ranged from 99 to 100%, which implied that only one type of begomovirus might be present. Based on the consensus sequences, a primer pair MB1AbF (ATGTGGGATCCACTTCTAAATGAATTTCC) and MB1AsR (GCGTCGACAGTGCAAGACAAACTACTTGGGGACC) was designed and used to amplify the circular viral DNA genome. The complete genome (Accession No. JQ326957) was 2,781 nucleotides long and had the highest sequence identity (over 99%) with Tomato yellow leaf curl virus (TYLCV; Accession Nos. GQ352537 and GU199587). These samples were also examined by dot immunobinding assay using monoclonal antibody against TYLCV and results confirmed that TYLCV was present in the samples. These results demonstrated that the virus from common bean is an isolate of TYLCV, a different virus from Tomato yellow leaf curl China virus (TYLCCNV). TYLCV is a devastating pathogen causing significant yield losses on tomato in China since 2006 (4). The virus has also been reported from cowpea in China (1) and in common bean in Spain (3). To our knowledge, this is the first report of TYLCV infecting common bean in China. References: (1) F. M. Dai et al. Plant Dis. 95:362, 2011. (2) D. Deng et al. Ann. Appl. Biol. 125:327, 1994. (3) J. Navas-Castillo et al. Plant Dis. 83:29, 1999. (4) J. B. Wu et al. Plant Dis. 90:1359, 2006.

Platelet-targeted microbubbles inhibit re-occlusion after thrombolysis with transcutaneous ultrasound and microbubbles

Microbubbles (MBs) can augment the acoustic cavitation' (US), thereby facilitating the thrombolysis of external ultrasound. But we observed re-thrombosis after successful thrombolysis by MBs and transcutaneous ultrasound in an endothelium injury model. This study was designed to explore whether platelet-targeted MBs can prevent the reformation of thrombi. Arterial injury was induced in canine femoral arteries with balloon, and the arteries were completely thrombotically occluded. The arteries were treated with intra-arterial MBs or platelet-targeted MBs (TMB) and transcutaneous low frequency ultrasound (LFUS) to achieve complete thrombolysis. The arterial flow was monitored with angiogram for 4h following treatment. Results showed that both MBs and TMBs produced successful dissolution of clots in the presence of ultrasound. The re-occlusion began to occur 1h after thrombolysis in MB/LFUS treatment, and 7 of 8 arteries were re-occluded within 3h. Most of the arteries (7 of 8) in the TMB/LFUS group remained patent for 4h following treatment. The flow tended to decrease after thrombolysis in MB/LFUS treatment. These results indicated that platelet-targeted microbubbles were beneficial in preventing re-thrombosis in vivo and microbubbles served as good carrier of thrombolytic and anticoagulation drugs.

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

Optical negative refraction in ferrofluids with magnetocontrollability

We numerically demonstrate optical negative refraction in ferrofluids containing isotropic Fe3O4 nanoparticles, each having an isotropic Ag shell, in the presence of an external dc magnetic field H. The all-angle broadband optical negative refraction with magnetocontrollability arises from H-induced chains or columns. They result in hyperbolic equifrequency contour for transverse magnetic waves propagating in the system. The finite element simulations verify the analyses using the effective medium approximation. Experimental demonstration and potential applications are suggested and discussed.

Adipose-derived stem cells from pregnant women show higher proliferation rate unrelated to estrogen

BACKGROUND

Adipose tissue contains an abundant population of multipotent adipose-derived stem cells (ASCs) and has been an excellent source of mesenchymal stem cells for cell therapy and tissue engineering. To ensure successful cell therapies, consistency of stem cell performance across donors is critical. However, the effect of the donor's reproductive status on ASC proliferation rate and differentiation capacity is undefined.

METHODS

We investigated whether the yield and function of ASCs are affected by the woman's reproductive status: pregnancy, premenopause or menopause. ASCs were isolated from the abdomen of 15 women and their proliferation rates and differentiation capacities were compared by cell count. The capacity of ASCs to differentiate into the chondrogenic lineage was investigated by quantitative real-time polymerase chain reaction and immunohistochemistry.

RESULTS

There was no significant difference in the differentiation capacity between the three groups, whereas the proliferation rate of ASCs from pregnant women was significantly higher than from the other two groups (P < 0.05). The proliferation rate of ASCs after estrogen treatment remained unchanged.

CONCLUSIONS

Despite the higher proliferation rate in pregnant women, ASCs showed consistency in cell differentiation capacity and were unaffected by donor status. This suggests that factors other than estrogen are responsible for the difference in proliferation.

Spinal cord changes after the evacuation of a spinal subdural haematoma

Spinal subdural haematoma is a rare entity. Only a few cases have been reported, mainly in patients with coagulopathies or bleeding diathesis, and also in patients undergoing anticoagulant therapy following surgery, trauma, or lumbar puncture. Symptoms of spinal cord compression produced by spinal subdural haematoma may progress rapidly causing complete and irreversible deficits. However, rapid diagnosis and surgical intervention can result in a good functional outcome for the patient. We report on a 41-year-old woman with a normal coagulation profile who developed a spinal subdural haematoma after a minor motor vehicle accident. Although initially asymptomatic, she developed a dense quadriparesis over a 36-h period. A magnetic resonance imaging study demonstrated a subdural mass compressing the spinal cord, and at surgery a spinal subdural haematoma was found. She was discharged to an inpatient rehabilitation facility. Follow-up at 1 year showed significant improvement in motor function, but absence of posterior column function. A follow-up magnetic resonance study demonstrated widening of the spinal cord, advanced myelomalacia and a large, central, multi-loculated syrinx.

Effects of hyper- and hypothyroid on expression of thyroid hormone receptor mRNA in rat myocardium

Thyroid dysfunction is classified into hyperthyroidism and congenital hypothyroidism (CH). Both hyperthyroidism and CH can cause heart lesions; however, the mechanisms involved remain unclear. The left ventricle was collected from eu-, hyper-, and hypothyroid rat. RNA was extracted and reverse-transcripted to cDNA. Real-time fluorescence quantitation-PCR was used to quantify the differential expression of thyroid hormone receptor (TR) subtype mRNA among eu-, hyper-, and hypothyroid rat myocardium. Here, we show that compared with the normal myocardium, TRalpha1 mRNA expression was upregulated by 51% (P<0.01), TRalpha2 mRNA expression was downregulated by 58% (P<0.01), and TRbeta1 mRNA expression remained unchanged in hyperthyroid rat myocardium (P>0.05). TRalpha1, TRalpha2, and TRbeta1 were expressed in normal and hypothyroid rat myocardium throughout the developmental process. In hypothyroid rats, myocardial TRalpha1 mRNA expression was generally downregulated and the expression peak appeared late. Myocardial TRalpha2 mRNA expression was generally upregulated and the expression peak appeared late. Myocardial TRbeta1 mRNA expression was generally downregulated and changed similarly with the control group. In addition, the hypogenetic myocardium can be seen in the hypothyroid rat by pathology study. Taken together, the abnormal expression of TR subtype mRNA may have a close relationship with the pathogenesis of CH and hyperthyroidism heart disease.

Magnetic plasmon propagation along a chain of connected subwavelength resonators at infrared frequencies

A one-dimensional magnetic plasmon propagating in a linear chain of single split ring resonators is proposed. The subwavelength size resonators interact mainly through exchange of conduction current, resulting in stronger coupling as compared to the corresponding magneto-inductive interaction. Finite-difference time-domain simulations in conjunction with a developed analytical theory show that efficient energy transfer with signal attenuation of less then 0.57 dB/microm and group velocity higher than 1/4c can be achieved. The proposed novel mechanism of energy transport in the nanoscale has potential applications in subwavelength transmission lines for a wide range of integrated optical devices.

Field study of a thermal environment and adaptive model in Shanghai

A long-term field investigation was carried out in naturally ventilated residential buildings in Shanghai from April 2003 to November 2004. A total of 1,768 returned questionnaires were collected in the study. This study deals with the thermal sensation of occupants in naturally ventilated buildings and the change in thermal neutral temperature with season. The range of accepted temperature in naturally ventilated buildings is between 14.7 degrees C T(op) and 29.8 degrees C T(op). The results also report the findings of the adaptive comfort model in Shanghai that determines the adaptive relationship of neutral temperature with outdoor air temperature. A long-term field study was carried out in residential buildings in Shanghai to find the relationship between thermal sensation, indoor neutral temperature and outdoor temperature. This paper presents findings of thermal comfort and discusses the more sustainable standard for the indoor climate of residential buildings in Shanghai.

17β-Estradiol suppresses proliferation of fibroblasts derived from cardinal ligaments in patients with or without pelvic organ prolapse

BACKGROUND

Estrogen replacement therapy (ERT) has been used in the treatment of pelvic organ prolapse (POP) but clinical results are inconclusive. The purpose of this study was to investigate the effect of 17beta-estradiol (E(2)) on the proliferation of fibroblasts derived from cardinal ligaments in women with or without POP.

METHODS

Fibroblasts were derived from seven patients with POP and seven age-matched controls. The growth rate of POP fibroblasts was compared with that of control by 3-(4,5,-dimethyl thiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) assay. Four cell strains from each patient and control group were treated with different concentrations of E2 (10(-4), 10(-8), 10(-9) and 10(-10) mol/l). The effect of E2 on cell proliferation was then measured by MTT assay.

RESULTS

The overall growth rate of POP fibroblasts was significantly slower than that of controls under normal culture conditions. Addition of E2 suppressed cell proliferation of all the fibroblasts, especially in POP fibroblasts. POP fibroblasts showed a significantly lower proliferative rate than that of controls at all E2 concentrations, with the most prominent inhibitory effect at physiological concentration (10.83 34.41% versus 81.56 48.10% at 10(-8) mol/l).

CONCLUSIONS

Our results suggest that decreased fibroblast turnover may contribute to the development of POP; and ERT may not be an effective POP treatment.

Epidemiology of hepatitis A and hepatitis E infection and their determinants in adult Chinese community in Hong Kong

Current epidemiology of hepatitis A virus (HAV) and hepatitis E virus (HEV) in Hong Kong was evaluated in 936 adult Chinese subjects recruited through a telephone interview in 2001. Some 15% of the subjects had IgG antibodies to both HAV and HEV while 665 (71.0%) and 176 (18.8%) had anti-HAV and anti-HEV, respectively. Age was the most significant independent factor. Six hundred thirty-eight (79.8%) and 165 (20.7%) subjects aged > or =30 had anti-HAV and anti-HEV, respectively, as compared with 27 (19.7%) and 11 (8.0%) in people aged <30. The corresponding adjusted Odds ratio (OR) was 14.94 (95% CI: 9.13-24.44; P<0.001) for anti-HAV positivity and 2.99 (95% CI: 1.58-5.67; P=0.001) for anti-HEV positivity. Subjects born outside Hong Kong were more likely to have anti-HAV (adjusted OR: 3.41; 95% CI: 2.21-5.26; P<0.001) but not anti-HEV. Non-labour work people were less likely to have anti-HAV-adjusted OR, 0.40 (95% CI: 0.26-0.62; P<0.001). Age-specific HAV prevalence right shifted in the last 20 years. Anti-HAV positivity was less frequent, across all age groups, in subjects >21-years-old in the present study than another study done in 1987-89 (P<0.001). HAV prevalence only increased slightly in every 10-year age groups of people aged 21-50 when compared with their corresponding 10-year-younger age groups (P=0.11), suggesting an ageing cohort effect with no major infections in the last decade. For HEV, both the overall and age-specific prevalence decreased over the last decade (P<0.001). The increasing proportion of susceptible population to enterically transmitted viral hepatitis has implications to future prevention and control programmes, including vaccination strategies.

Near-threshold production of the multistrange Xi- hyperon

The yield for the multistrange Xi(-) hyperon has been measured in 6A GeV Au+Au collisions via reconstruction of its decay products pi(-) and Lambda, the latter also being reconstructed from its daughter tracks of pi(-) and p. The measurement is rather close to the threshold for Xi(-) production and therefore provides an important test of model predictions. The measured yield for Xi(-) and Lambda are compared for several centralities. In central collisions the Xi(-) yield is found to be in excellent agreement with statistical and transport model predictions, suggesting that multistrange hadron production approaches chemical equilibrium in high baryon density nuclear matter.

Comparison of source images for protons, pi-'s, and lambda's in 6A GeV Au+Au collisions

Source images are extracted from two-particle correlations constructed from strange and nonstrange hadrons produced in 6A GeV Au+Au collisions. Very different source images result from pp vs p Lambda vs pi(-)pi(-) correlations. Scaling by transverse mass can describe the apparent source size ratio for p/pi(-) but not for Lambda/pi(-) or Lambda/p. These observations suggest important differences in the space-time emission histories for protons, pions, and neutral strange baryons produced in the same events.

[Studies on risk factors for liver fibrosis of schistosomiasis japonica]

OBJECTIVE

To explore the risk factors for schistosomal liver fibrosis.

METHODS

192 hepatitis-negative patients with schistosomiasis were selected and divided into 3 groups according to the result of B ultrasound examination, that is, grade 2 and 3 fibrosis group(81 patients), grade 1 fibrosis group (61 patients) and control group (non-fibrosis, 50 patiets). The univariate and multivariate ordinal regression model was made to analyse the possibly harmful factors influencing the liver damages of these patients.

RESULTS

Four factors were found to be positively associated with schistosomal liver fibrosis. They were: number of treatments of schistosomiasis (OR = 1.75), interval of schistosomal infection(OR = 1.40), history of drinking wine (OR = 1.95) and familial history of advanced schistosomiasis (OR = 2.11).

CONCLUSION

Patients with repeated schistosome infection, long duration of schistosomal infection, long history of drinking and familial history of advanced schistosomiasis had higher risk for liver fibrosis than schistosomiasis patients without these factors.

Longitudinal flow of protons from (2-8)A GeV central Au+Au collisions

Rapidity distributions of protons from central 197Au+197Au collisions measured by the E895 Collaboration in the energy range from (2-8)A GeV at the Brookhaven AGS are presented. Longitudinal flow parameters derived using a thermal model including collective longitudinal expansion are extracted from these distributions. The results show an approximately linear increase in the longitudinal flow velocity, <betagamma>(L), as a function of the logarithm of beam energy.

Ultrasensitive chemiluminescence detection of sub-fM level Co(II) in capillary electrophoresis

A method of on-line ultrasensitive chemiluminescence detection with capillary electrophoresis for Co(II) is reported. Using our newly developed capillary electrophoresis with chemiluminescence detection system and novel mixing mode of the reagents, the effects of field-amplified injection on detection limits of metal ions were studied in detail. The sub-fM level (1.3 x 10(-16) M, 1.6 x 10(-24) mol, 1 molecule) detection of cobalt ions in ultradilute solution was performed. The catalytic behavior of the chemiluminescence reaction of luminol and hydrogen peroxide by cobalt ions and the reaction conditions, such as the concentration of luminol, H2O2, and pH of chemiluminescence reagent were investigated. The separation of fM level Co(II) and trace amounts of Ni(II) was performed successfully.

Determination of free aspartic acid enantiomers in rat brain by capillary electrophoresis with laser-induced fluorescence detection

Quantification of aspartic acid enantiomers in rat brain by using a chiral capillary electrophoresis procedure is described. Amino acids were pre-column derivatized with naphthalene-2,3-dialdehyde. Enantiomeric separation was achieved by micellar electrokinetic chromatography in the presence of methanol and beta-cyclodextrin as chiral selector. The chiral separation was coupled with laser-induced fluorescence detection. Contents of D- and L-aspartic acids in rats at different stages of growth (from 1 day before birth to 90 days after birth) were determined. D-Aspartic acid was detected in all the brain tissue samples tested, but at different levels. In the cerebrum of rats 1 day before birth, D-aspartic acid was found to be at the highest concentration of 81 nmol/g wet tissue. The level of D-aspartic acid in rat brain falls rapidly after birth, while the L-aspartic acid level increases with age.

Effects of endothelin receptor A antagonist FR139317 on rats with congestive heart failure

AIM

To study the effects of a selective endothelin receptor A (ETA) antagonist FR139317 on rats with congestive heart failure.

METHODS

A congestive heart failure model was established via left coronary artery ligation in adult male Wistar rats. The rats with congestive heart failure were treated with FR139317 at two doses (1 and 5 mg . kg-1 . d-1 respectively for 6 weeks) or with vehicle. Hemodynamics, plasma level of endothelin-1 (ET-1), and mortality rate of rats were measured.

RESULTS

Both groups treated with FR139317 (high and low dose) have lower mortality rate (25.0 % and 28.6 % vs 50.0 %) and lower plasma level of ET-1 than that of vehicle [(3.6 +/- 1.2) ng/L and (4.9 +/- 1.5) ng/L vs (5.8 +/- 1.3) ng/L]. Comparing to vehicle group, left ventricular end-diastolic pressures of the FR139317-treated groups were improved significantly [(12 +/- 6) mmHg and (14 +/- 7) mmHg vs (22 +/- 9) mmHg]. FR139317 at a higher dose reduced the mean arterial pressure of the rats with congestive heart failure and decreased the plasma concentration of endothelin to a closer level of rats with normal heart function than lower dose.

CONCLUSION

Selective ETA antagonist FR139317 improved the hemodynamics and reduced the plasma ET-1 level and the mortality of rats with congestive heart failure

[Study on the structural property of polysacchrides 139A--a kind of IL-1R antagonists from microorganism]

AIM

To study the structural property of the bioactive component from the fermentation broth of Streptomyces 139 which can inhibit IL-1R.

METHODS

Polysaccharide 139A is extracted and purified by means of macroreticular resin Diaion HP-20, cation exchange and DEAE Sephadex A-25 chromatography. The sugar compositions were analyzed with GC, the linkage positions of 139A were determined by methylation and GC-MS.

RESULTS

The bioactive component which can inhibit IL-1R is a kind of polysaccharides.

CONCLUSION

The components of 139A repeat units are conjectured.