Local aldosterone release and CYP11B2 expression in response to angiotensin peptides, glucose, and potassium - an ex vivo study on murine colon

We have previously described local aldosterone synthesis in mouse colon. In the renin-angiotensin-aldosterone system (RAAS), angiotensin II (Ang II) peptide is the physiological factor which stimulates aldosterone synthesis in the adrenal glands. We have recently demonstrated that Ang II stimulates aldosterone synthesis also in mouse colon. Here, we conducted a 75-min ex vivo incubation of murine colonic tissue and evaluated the effects of three other Ang peptides, Ang I (1 μM), Ang III (0.1 μM) and Ang (1-7) (0.1 μM) on aldosterone synthesis. As a possible mechanism, their effects on tissue levels of the rate-limiting enzyme, aldosterone synthase (CYP11B2) were measured by ELISA and Western blot. Ang III significantly elevated the amount of tissue CYP11B2 protein in colon. The values of released aldosterone in colon tissue incubation were increased over the control in the presence of Ang I, II or III, however, being statistically non-significant. In Western blot analysis, the values of tissue CYP11B2 protein content were elevated by Ang I and II. Ang (1-7) alone in colon did not influence CYP11B2 protein levels in the incubation experiment but showed higher aldosterone release without statistical significance. Ang (1-7) showed an antagonistic effect towards Ang II in release of aldosterone in adrenal gland. An overall estimation of a single peptide (three measured variables), the results were always in an increasing direction. The responses of aldosterone synthesis to high levels of glucose (44 mM) and potassium (18.8 mM) as physiological stimulators in vivo were investigated in the colon incubation. Glucose, equal to four times the concentration of the control buffer in the incubation, showed higher values of aldosterone release in colon than control without statistical significance similarly to the effect seen in adrenal glands. Increasing the concentration of potassium in the incubation buffer exerted no effect on colonic aldosterone production. Intriguingly, no correlation was found between aldosterone release and the tissue CYP11B2 protein content in colon. In summary, the response of colonic aldosterone synthesis to different Ang peptides resembles, but is not identical to, the situation in the adrenal glands.

Age effect on the shared etiology of glycemic traits and serum lipids: evidence from a Chinese twin study

PURPOSE

Diabetes and dyslipidemia are among the most common chronic diseases with increasing global disease burdens, and they frequently occur together. The study aimed to investigate differences in the heritability of glycemic traits and serum lipid indicators and differences in overlapping genetic and environmental influences between them across age groups.

METHODS

This study included 1189 twin pairs from the Chinese National Twin Registry and divided them into three groups: aged ≤ 40, 41-50, and > 50 years old. Univariate and bivariate structural equation models (SEMs) were conducted on glycemic indicators and serum lipid indicators, including blood glucose (GLU), glycated hemoglobin A1c (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), in the total sample and three age groups.

RESULTS

All phenotypes showed moderate to high heritability (0.37-0.64). The heritability of HbA1c demonstrated a downward trend with age (HbA1c: 0.50-0.79), while others remained relatively stable (GLU: 0.55-0.62, TC: 0.58-0.66, TG: 0.50-0.63, LDL-C: 0.24-0.58, HDL-C: 0.31-0.57). The bivariate SEMs demonstrated that GLU and HbA1c were correlated with each serum lipid indicator (0.10-0.17), except HDL-C. Except for HbA1c and LDL-C, as well as HbA1c and HDL-C, differences in genetic correlations underlying glycemic traits and serum lipids between age groups were observed, with the youngest group showing a significantly higher genetic correlation than the oldest group.

CONCLUSION

Across the whole adulthood, genetic influences were consistently important for GLU, TC, TG, LDL-C and HDL-C, and age may affect the shared genetic influences between glycemic traits and serum lipids. Further studies are needed to elucidate the role of age in the interactions of genes related to glycemic traits and serum lipids.

[The mechanism by which hsa_circRNA_103124 highly expressed in peripheral blood of patients with active Crohn's disease regulates macrophage differentiation, pyroptosis and inflammation]

Objective: To investigate the role and related mechanism of the highly expressed circular RNA molecule 103124 (hsa_circRNA_103124) in macrophage differentiation, pyroptosis and inflammation in peripheral blood mononuclear cells (PBMC) of patients with active Crohn's disease (CD). Methods: Patients with active CD (CD group) admitted to the Affiliated Suzhou Hospital of Nanjing Medical University from April to September 2018 and healthy people (control group) from the physical examination center of the hospital from July to October 2018 were retrospectively selected. The levels of hsa_circRNA_103124 and Toll-like receptor 4 (TLR4) in PBMC of the two groups were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Tohoku hospital pediatrics-1 (THP1) cell line was used as a model for the study of hsa_circRNA_103124 regulating macrophage differentiation. Lentivirus infection was used to construct hsa_circRNA_103124 overexpressed or down-regulated THP1 cells to induce macrophage-like differentiation. According to the expression level of hsa_circRNA_103124, THP1 cell lines were divided into the following four groups: pLC5-ciR was overexpression control group; hsa_circRNA_103124 OE was the overexpression group; ShRNActrl was down-regulated expression control group; hsa_circRNA_103124 ShRNA was the down-regulated expression group. Flow cytometry was used to detect levels cluster of differentiation (CD) 68, CD80, interleukin (IL)-6, tumor necrosis factor α (TNF-α) and reactive oxygen species (ROS). The expression levels of IL-6, TNF-α, IL-1β, TLR4 and myeloid differentiation factor 88 (MyD88) were detected by RT-qPCR. The levels of gasdermin D (GSDMD), IL-18 and NOD-like receptor thermal protein domain associated protein 3 (NLRP3) were determined by immunofluorescence and RT-qPCR. Pearson correlation analysis was used to analyze the correlation between the abundance of hsa_circRNA_103124 and TLR4 expression level or Crohn's disease activity index (CDAI). Results: A total of 50 patients were included in the CD group, including 36 males and 14 females, aged (35±10) (19-64) years. A total of 30 subjects were included in the control group, including 22 males and 8 females, aged (38±9) (24-64) years. hsa_circRNA_103124 [(0.009±0.016) vs (0.003±0.002), P=0.042] and TLR4 [(0.005±0.003) vs (0.001±0.001), P<0.001] were all upregulated in the PBMC of patients in the CD group, compared with the control group. And hsa_circRNA_103124 was positively correlated with TLR4 (r=0.40, P=0.004). hsa_circRNA_103124 level was positively correlated with CDAI (r=0.32, P=0.024). The expression of CD68 (P=0.002) and CD80 (P<0.001) were enhanced. hsa_circRNA_103124 promoted production of ROS and the expression of IL-6, TNF-α, IL-1β, TLR4, MyD88, GSDMD, IL-18 and NLRP3 in macrophage-like M1 differentiated THP1 cells (all P<0.05). Conclusion: High expresion of hsa_circRNA_103124 in PBMC of patients with active CD may promote macrophage M1 differentiation, pyroptosis and inflammation through enhancing the expression of TLR4, MyD88, NLRP3 and GSDMD.

[The diagnostic and evaluation value of plasma interleukin 9 in the mucosal healing in patients with inflammatory bowel disease treated with biological agents]

Objective: To investigate the diagnostic and evaluation value of plasma interleukin 9 (IL9) in the mucosal healing (MH) in patients with inflammatory bowel disease (IBD) treated with biological agents. Methods: Cohort study. IBD patients (137 cases) treated in the Affiliated Suzhou Hospital to Nanjing Medical University (Suzhou Municipal Hospital) from September 2019 to January 2022 were prospective selected. Each patient was treated with biological agents [Infliximab (IFX, 56 cases), Adalimumab (ADA, 20 cases), Ustekinumab (UST, 18 cases), Vedolizumab (VDZ, 43 cases)]. According to different therapeutic drugs, the IFX, ADA, UST, and VDZ group were divided. Clinical symptoms, inflammatory indicators and imaging examinations etc. were evaluated every 8 weeks, and the degree of MH was evaluated by endoscopy at the 54th week. The expression of plasma IL9 was detected by ELISA after initial enrollment (W 0) and 8 weeks of biological treatment (W 8). Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic efficacy of IL9 for MH. Select the cut off value for the optimal ROC threshold based on the highest value of the Youden index. Spearman's rank correlation was used to analyze the correlation between IL9 and Simple Endoscopic Score for CD (SES-CD) and Mayo Endoscopic Score (MES), so as to evaluate the predictive value of IL9 for MH in IBD patients treated with biologic agents. Results: Among the 137 patients, there were 97 Crohn's disease (CD) patients, 53 males and 44 females, aged (31.6±10.3) years (18-60 years). There were 40 ulcerative colitis (UC) patients, 22 males and 18 females, aged (37.5±14.7) years (18-67 years). Among the CD patients, 42 cases (43.3%) achieved MH on endoscopy at the 54th week, and 60 patients (61.9%) achieved clinical remission. Among the UC patients, 22 cases (55.0%) achieved MH and 30 cases (75.0%) achieved clinical remission. At W 0, the relative expression of IL9 in patients in IBD patients who achieved MH after 54 weeks of biological treatment was lower than that in the non-MH patients [x¯±s, (127.42±34.43) vs (146.82±45.64) ng/L, (113.01±44.88) vs (146.12±48.66) ng/L, respectively, both P<0.05]. At W 8, the relative expression of IL9 in the MH group was lower than that in the non-MH patients (both P<0.05). The relative expression of IL9 in the MH patients after IFX treatment was lower than that in the non-MH group (P<0.05). There was no significant difference among the other groups between MH and non-MH patients (all P>0.05). IL9 at W 8 showed high value in predicting MH in IBD [CD patients: area under curve (AUC)=0.716(95%CI: 0.616-0.817, P<0.001), sensitivity and specificity were 80.77%(95%CI:67.64%-88.45%) and 48.89%(95%CI: 35.53%-64.47%), respectively; UC patients: AUC=0.821, sensitivity and specificity were 77.78% and 72.73%, respectively]. At W 8, the cut off values for CD and UC patients were IL9>80.77 ng/L and IL9>77.78 ng/L, respectively. IL9 was positively correlated with endoscopic MH score parameters [M(Q₁,Q₃),SES-CD: 3.0(8.5, 18.5); MES: 2.0(1.0, 3.0)] (r=0.55, 0.72, respectively, both P<0.001) at W8. Conclusion: The plasma IL-9 at the week 8 after biological agents treatment can be used to diagnose and evaluate the MH of patients with IBD.

Intestinal aldosterone synthase activity and aldosterone synthesis in mouse

Aldosterone is the most important mineralocorticoid hormone regulating water and electrolyte absorption in the distal convoluted tubule of the kidney. Recently, we detected the presence of the whole chain of aldosterone production from the precursor corticosterone, transcription factor liver receptor homologue-1 (LRH-1), the aldosterone synthase enzyme protein (CYP11B2) as well as the gene to the final product aldosterone in murine large intestine. Here, we decided to correlate the amount of this synthase protein with its enzymatic activity in different parts of gastrointestinal tract and also with the aldosterone concentration in the respective tissue. Considering the physiological behavior of the animals in light and dark environment, we measured these variables at four time points - two in the light, the others during darkness. In vitro activity of CYP11B2 was measured as the amount of aldosterone formed from the precursor deoxycorticosterone using enzyme preparations from homogenized intestinal sections. CYP11B2 enzyme activity was higher in the large than in the small intestine. In ileum and colon, the CYP11B2 activity increased in the dark time. The highest aldosterone concentration was detected in the dark in the large intestine. In summary, enzyme activity of CYP11B2 was present in all parts of intestine; the large intestine formed more aldosterone during the darkness. No difference was seen in any of the variables between the early and late light hours.

Cell-Trappable BODIPY-NBD Dyad for Imaging of Basal and Stress-Induced H2S in Live Biosystems

H₂S is a gaseous signaling molecule that is involved in many physiological and pathological processes. In general, the level of intracellular H₂S (<1 μM) is much lower than that of GSH (∼1-10 mM), leading to the remaining challenge of selective detection and differentiation of endogenous H₂S in live biosystems. To this end, we quantitatively demonstrate that the thiolysis of NBD amine has much higher selectivity for H₂S over GSH than that of the reduction of aryl azide. Subsequently, we developed the first NBD-based cell-trappable probe 1 (AM-BODIPY-NBD) for highly selective and ultrasensitive imaging of intracellular H₂S. Probe 1 demonstrates a 207-fold fluorescence enhancement at 520 nm after reaction with H₂S/esterase to produce a bright BODIPY (quantum yield 0.42) and a detection limit of 15.7 nM. Probe 1 is water-soluble, cell-trappable, and not cytotoxic. Based on this excellent chemical tool, relative levels of basal H₂S in different cell lines were measured to reveal a positive correlation between endogenous H₂S and the metastatic potential of colon and breast cancer cells. In addition, H₂S biogenesis in vivo was also validated by probe 1 both in tobacco leaves under viral infection and in zebrafish after tail amputation. It is anticipated that probe 1 will have widespread applications in imaging and for investigating different H₂S-related biological processes and diseases.

Evidence for local aldosterone synthesis in the large intestine of the mouse

Aldosterone, the main physiological mineralocorticoid, regulates sodium and potassium balance in the distal convoluted tubule of the kidney. Aldosterone is synthesized from cholesterol in the adrenal cortex in a sequence of enzymatic steps. Recently however, several tissues or cells e.g. brain, heart, blood vessels, kidneys and adipocytes have been shown to possess capability to produce aldosterone locally, and there is some evidence that this occurs also in the intestine. Colon expresses mineralocorticoid receptors and is capable of synthesizing corticosterone, the second last intermediate on the route to aldosterone from cholesterol. Based on such reports and on our preliminary finding, we hypothesized that aldosterone could be synthesized locally in the intestine and therefore we measured the concentration of aldosterone as well as the protein and gene expression of aldosterone synthase (CYP11B2), an enzyme responsible on aldosterone synthesis, from the distal section of the gastrointestinal tract of 10-week-old Balb/c male mice. It is known that sodium deficiency regulates aldosterone synthesis in adrenal glands, therefore we fed the mice with low (0.01%), normal (0.2%) and high-sodium (1.6%) diets for 14 days. Here we report that, aldosterone was detected in colon and cecum samples. Measurable amounts of CYP11B2 protein were detected by Western blot and Elisa analysis from both intestinal tissues. We detected CYP11B2 gene expression from the large intestine along with immunohistochemical findings of CYP11B2 in colonic wall. Sodium depletion increased the aldosterone concentration in plasma compared to control and high-sodium groups as well as in the intestine compared to mice fed with the high-sodium diet. To summarize, this study further supports the presence of aldosterone and the enzyme needed to produce this mineralocorticoid in the murine large intestine.

Integrated microRNA-mRNA analysis reveals the roles of microRNAs in the muscle fat metabolism of Yanbian cattle

Fat deposition is an important economic trait in farm animals. However, it is difficult to genetically improve intramuscular fat deposition via trait-based cattle breeding. The main objectives of this study were to analyze the factors about beef flavor, and to detect functional microRNA (miRNA, miR) associated with intramuscular fat deposition in Yanbian cattle. Longissimus dorsi samples from six steers were separated into high- and low-fat groups (n = 3 each) based on the marbling score, and transcriptomic analysis was performed using miRNA sequencing. A total of 33 miRNAs and 38 genes were found to be differentially expressed in the high- and low-fat groups. Quantitative real-time polymerase chain reaction was performed to validate the sequencing results. Integrated miRNA-mRNA analysis revealed that miRNA-associated target genes were primarily associated with skeletal muscle development. However, some of the miRNAs (miR-424 etc.) and genes (ATF3 etc.) were also associated with fat metabolism. A targeted relationship between miR-22-3p and the WFIKKN2 gene and its involvement in adipocyte differentiation were confirmed experimentally. The study findings may provide potential candidate molecular targets for the selection of cattle with improved meat quality.

A H2 S-Specific Ultrasensitive Fluorogenic Probe Reveals TMV-Induced H2 S Production to Limit Virus Replication

Understanding the role of H₂ S in host defense mechanisms against RNA viruses may provide opportunities for the development of antivirals to combat viral infections. Here, we have developed a green-emitting fluorogenic probe, which exhibits a large fluorescence response at 520 nm (>560-fold) when treated with 100 μM H₂ S for 1 h. It is highly selective for H₂ S over biothiols (>400-fold F/F₀ ) and has a detection limit of 12.9 nM. We demonstrate the application of the probe for endogenous H₂ S detection in vivo for the understanding of its roles in antiviral host defense. Such virus-induced H₂ S inhibits viral replication by reducing gene expression of RNA-dependent RNA polymerase (RdRp) and coat protein (CP). Additionally, a H₂ S donor GYY4137 showed significantly antiviral activity as ribavirin, a broad-spectrum drug against RNA viruses. Furtherly, we propose a possible molecular mechanism for the TMV-induced H₂ S biogenesis. This work provides a proof-of-principle in support of further studies identifying endogenous H₂ S and its donors as potential antivirals toward RNA viruses.

Genetically encoding ε-N-benzoyllysine in proteins

Genetically encoding BzK can facilitate the biological investigation of the recently discovered protein PTM lysine ε-N-benzoylation.

Comparative Studies of Potential Binding Pocket Residues Reveal the Molecular Basis of ShHTL Receptors in the Perception of GR24 in Striga

Root parasitic weeds such as Striga spp. have caused significant losses in agriculture production worldwide. The seed germination of the weeds depends on strigolactones (SLs) that target a series of HYPOSENSITIVE TO LIGHT/KARRIKIN INSENSITIVE2 in Striga hermonthica (ShHTL) proteins. In the present study, 60 ShHTL7 mutants were constructed, and the equilibrium dissociation constants for GR24 (a synthetic SL analogue, commonly used as a standard in SL germination studies) against these mutants were measured by surface plasmon resonance. Based on these data, the SL binding pocket residues were distinguished. Of them, some specific residues for ShHTL7 were found, such as T142, T190, and M219. A model showing quite well internal and external predictive abilities was established by the mutation-dependent biomacromolecular quantitative structure-activity relationship method. It provided an expanded understanding for GR24 binding to a series of ShHTL receptors and should help design broad-spectrum agrochemicals with cross interactions with several members of SL receptors.

Platelet membrane-coated nanoparticles target sclerotic aortic valves in ApoE−/− mice by multiple binding mechanisms under pathological shear stress

Background

Aortic valve disease is the most common valvular heart disease leading to valve replacement. The efficacy of pharmacological therapy for aortic valve disease is limited by the high mechanical stress at the aortic valves impairing the binding rate. We aimed to identify nanoparticle coating with entire platelet membranes to fully mimic their inherent multiple adhesion mechanisms and target the sclerotic aortic valve of apolipoprotein E-deficient (ApoE−/−) mice based on their multiple sites binding capacity under high shear stress.

Methods

Considering the potent interaction of platelet membrane glycoproteins with components present in sclerotic aortic valves, platelet membrane-coated nanoparticles (PNPs) were synthetized and the binding capacity under high shear stress was evaluated in vitro and in vivo.

Results

Compared with PNPs bound intensity in the static station, 161%, 59%, and 39% of attached PNPs remained adherent on VWF-, collagen-, and fibrin-coated surfaces under shear stress of 25dyn/cm2 respectively. PNPs demonstrated effectively adhering to von Willebrand factor, collagen and fibrin under shear stresses in vitro. In an aortic valve disease model established in ApoE−/− mice, PNPs group exhibited significant increase of accumulation in the aortic valves compared with PBS and control NP group. PNPs displayed high degrees of proximity or co-localization with vWF, collagen and fibrin, which exhibited good targeting to sclerotic aortic valves by mimicking platelet multiple adhesive mechanisms.

Conclusion

PNPs could provide a promising platform for the molecular diagnosis and targeting treatment of aortic valve disease.

Targeting combination

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Natural Science Foundation of China

Strigolactone Analogues Derived from Dihydroflavonoids as Potent Seed Germinators for the Broomrapes

The broomrapes (Orobanche and Phelipanche spp.) and witchweeds (Striga spp.) are a class of parasitic weeds, which are distributed widely in the tropical, subtropical, and temperate areas of the globe. Since they have completely consistent lifecycles with the host plants, it is difficult to control them selectively through using the conventional herbicides. Inducing suicidal germination of these weed seeds by small molecular signaling agents proved to be a promising strategy for the management of parasitic weeds. As a class of naturally occurring terpenoid metabolites, strigolactones (SLs) show significant biological activities including stimulation germination of weed seeds, inhibition of shoot-branching, and so on. However, the widespread application of these natural SLs is greatly limited by their extremely low natural abundance and complex molecular structures. Design and synthesis of the simplified analogues as natural SLs alternatives provide a viable avenue for the efficient control of these parasitic weeds. We herein disclose the development of a novel class of SLs analogues derived from dihydroflavonoids as potent seed germinators of parasitic weeds. It was shown that one of them displayed a higher potential toward the seed germination of the broomrapes than the positive control GR24. The structure-activity relationship of these SLs analogues was further validated on the basis of the binding affinity experiment to strigolactone receptor protein HTL7 by using a YLG fluorescent probe method.

Antifungal mechanism of Streptomyces ma. FS-4 on fusarium wilt of banana

AIM

Research on prevention and cure of banana wilt is important to ensure the healthy development of the banana industry. In this study, antifungal mechanism of Streptomyces ma. FS-4 on fusarium wilt of banana was investigated.

METHODS AND RESULTS

The physiological strain of banana fusarium pathogen Fusarium oxysporum f. sp. cubense Race 4 (FOC.4) was used as the target fungus, and the antifungal mechanism of the crude extract of Streptomyces ma. FS-4 was investigated. Eighteen different compounds identified by gas chromatography-mass spectrometry were composed of aldehydes, methyl, hydrocarbons, amides, esters and acids. FS-4 significantly inhibited the spore germination of the target fungi, with an EC₅₀ of 22·78 μg ml^-1 . After treatment with 100 μg ml^-1 FS-4 crude extract, the N-acetylglucosamine content in the mycelium increased 1·95-fold. However, the extract had no significant effect on β-1,3-glucanase. At the FS-4 crude extract dose of 100 μg ml^-1 , the total sugar and protein contents decreased by 28·6 and 29·1% respectively, and the fat content was 41·3%. FS-4 significantly inhibited the activity of the mitochondrial complex III of Foc4, which was reduced by 52·45%. Moreover FS-4 reduced the activity of succinate dehydrogenase, a key enzyme in the Krebs cycle, by 60·2%. However, FS-4 had no significant effect on malate dehydrogenase. The membrane potential on the mitochondrial inner membrane was significantly reduced at the test concentration of 100 μg ml^-1 . ROS gradually accumulated in the Foc4 hypha, and the burst was 3·97 times higher than the control.

CONCLUSIONS

This study demonstrated that the antifungal mechanism of Streptomyces ma. FS-4 against Foc4 includes the destruction of the plasma membrane and mitochondrial dysfunction and finally induction of cell apoptosis.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results may indicate the prevention and control of banana wilt, which is of great significance to the healthy development of banana industry system.

The Chinese National Twin Registry: a 'gold mine' for scientific research

The Chinese National Twin Registry (CNTR) currently includes data from 61 566 twin pair from 11 provinces or cities in China. Of these, 31 705, 15 060 and 13 531 pairs are monozygotic, same-sex dizygotic and opposite-sex dizygotic pairs, respectively, determined by opposite sex or intrapair similarity. Since its establishment in 2001, the CNTR has provided an important resource for analysing genetic and environmental influences on chronic diseases especially cardiovascular diseases. Recently, the CNTR has focused on collecting biologic specimens from disease-concordant or disease-discordant twin pairs or from twin pairs reared apart. More than 8000 pairs of these twins have been registered, and blood samples have been collected from more than 1500 pairs. In this review, we summarize the main findings from univariate and multivariate genetic effects analyses, gene-environment interaction studies, omics studies exploring DNA methylation and metabolomic markers associated with phenotypes. There remains further scope for CNTR research and data mining. The plan for future development of the CNTR is described. The CNTR welcomes worldwide collaboration.

[Expression of microRNA-155 in inflammatory bowel disease and its clinical significance]

Objective: To explore the expression of microRNA-155 in colonic mucosa and peripheral blood in patients with inflammatory bowel disease(IBD), and to examine the clinical value and significance of microRNA-155 in the diagnosis of IBD. Methods: Quatitative reverse-transcription PCR was performed to detect the expression of microRNA-155 in 20 patients with Crohn disease(CD), 21 patients with ulcerative colitis (UC), 18 patients with IBD type unclassified(IBDU), 25 healthy people(control group), 12 patients with infection colitis and 19 patients with ischemia colitis.Receiver operating characteristic (ROC) curve was performed to analyze the clincal value of microRNA-155 in diagnosis of IBD. Results: The expression of microRNA-155 in colonic mucosa in CD, UC and IBDU group was significantly higher than that in control group(P<0.05). MicroRNA-155 expression was also significantly higher in UC group in comparison to CD group (35.4±3.0 vs 18.6±5.9, P<0.01), IBDU group in comparison to CD group (23.0±3.7 vs 18.6±5.9, P<0.05) and UC group in comparison to IBDU group (35.4±3.0 vs 23.0±3.7, P<0.01). The plasma level of microRNA-155 in UC group (55.6±2.5) and IBDU group (48.1±6.2) was significantly higher than that in control group(P<0.05), while no significant difference in CD group was observed when compared with control group(P>0.05). ROC curve shows an AUC of 0.83 and 95%CI of 0.679-0.986 of microRNA-155 expression in colonic mucosa.The sensitivity and specificity of microRNA-155 expression in colonic mucosa in diagnosis of IBD was 68.4% and 78.6%, respectively. Conclusions: MicroRNA-155 showed high expression in colonic mucosa and peripheral blood in patients with IBD.MicroRNA-155 shows promise as a biomarker in diagnosis of IBD.Furthermore, the aberrant expression indicates that microRNA-155 may be involved in pathogenesis and progression of IBD.

Associations between birth size and later height from infancy through adulthood: An individual based pooled analysis of 28 twin cohorts participating in the CODATwins project

BACKGROUND

There is evidence that birth size is positively associated with height in later life, but it remains unclear whether this is explained by genetic factors or the intrauterine environment.

AIM

To analyze the associations of birth weight, length and ponderal index with height from infancy through adulthood within mono- and dizygotic twin pairs, which provides insights into the role of genetic and environmental individual-specific factors.

METHODS

This study is based on the data from 28 twin cohorts in 17 countries. The pooled data included 41,852 complete twin pairs (55% monozygotic and 45% same-sex dizygotic) with information on birth weight and a total of 112,409 paired height measurements at ages ranging from 1 to 69 years. Birth length was available for 19,881 complete twin pairs, with a total of 72,692 paired height measurements. The association between birth size and later height was analyzed at both the individual and within-pair level by linear regression analyses.

RESULTS

Within twin pairs, regression coefficients showed that a 1-kg increase in birth weight and a 1-cm increase in birth length were associated with 1.14-4.25 cm and 0.18-0.90 cm taller height, respectively. The magnitude of the associations was generally greater within dizygotic than within monozygotic twin pairs, and this difference between zygosities was more pronounced for birth length.

CONCLUSION

Both genetic and individual-specific environmental factors play a role in the association between birth size and later height from infancy to adulthood, with a larger role for genetics in the association with birth length than with birth weight.

[Significance of serum calprotectin in assessing inflammatory bowel disease activity]

Objective: To investigate the application value of serum calprotectin in assessing the activity of IBD Methods: Eighty-five Crohn's disease(CD) and eighty-five Ulcerative colitis(UC) patients at Suzhou Municipal Hospital(North Branch) from August 2015 to January 2017 were enrolled in this study, and eighty-five healthy subjects were selected as controls. Serum level of calprotectin was determined by ELISA. Correlation of serum calprotectin with clinical features of IBD was analyzed. The diagnostic efficacy for CD and UC were assessed by ROC curve. Results: The level of serum calprotectin was significantly higher in IBD patients than in healthy subjects. Positive correlations were found between serum calprotectin level and CRP, ESR, fecal calprotectin level of IBD(ρ＝0.341, P<0.001；ρ＝0.438, P<0.001；ρ＝0.542, P<0.001，respectively). Besides, positive correlations were found between serum calprotectin level with disease activity index(CDAI or Mayo score) of IBD(ρ＝0.309, P＝0.004；ρ＝0.227, P＝0.036，respectively)．Nevertheless, no correlation was found between serum calprotectin level with location of IBD and disease subtypes(P>0.05)．The area under curve(AUC) of serum calprotectin for diagnosis of CD and UC were 0.946 and 0.906, respectively. Conclusions: Serum level of calprotectin is associated with the activity of IBD. As a result，serum level of calprotectin may has the potential to be served as a clinical index of IBD activity.

Quantitative proteomics links metabolic pathways to specific developmental stages of the plant-pathogenic oomycete Phytophthora capsici

The oomycete Phytophthora capsici is a plant pathogen responsible for important losses to vegetable production worldwide. Its asexual reproduction plays an important role in the rapid propagation and spread of the disease in the field. A global proteomics study was conducted to compare two key asexual life stages of P. capsici, i.e. the mycelium and cysts, to identify stage-specific biochemical processes. A total of 1200 proteins was identified using qualitative and quantitative proteomics. The transcript abundance of some of the enriched proteins was also analysed by quantitative real-time polymerase chain reaction. Seventy-three proteins exhibited different levels of abundance between the mycelium and cysts. The proteins enriched in the mycelium are mainly associated with glycolysis, the tricarboxylic acid (or citric acid) cycle and the pentose phosphate pathway, providing the energy required for the biosynthesis of cellular building blocks and hyphal growth. In contrast, the proteins that are predominant in cysts are essentially involved in fatty acid degradation, suggesting that the early infection stage of the pathogen relies primarily on fatty acid degradation for energy production. The data provide a better understanding of P. capsici biology and suggest potential metabolic targets at the two different developmental stages for disease control.

Maternal anti-HBVs suppress the immune response of infants to hepatitis B vaccine

It is still controversial whether maternal anti-HBV antibodies (anti-HBVs) affect the infants' immune response to hepatitis B virus (HBV) vaccination. This multicentre study aims to address this question. First, we determined whether the transplacental transfer of maternal anti-HBVs occurs by measuring the titres of 90 anti-HBVs-positive pregnant women and their newborns. The anti-HBVs-positive rates of newborns ranged from 89.7% to 100.0%, depending on the maternal anti-HBVs titres. Secondly, we investigated the effects of maternal anti-HBVs on the immune response of infants to HBV vaccination. A total of 1063 mother-and-infant pairs were enrolled and divided into three groups with maternal anti-HBVs titres of <10 IU/L (negative - 37.9%), 10-499 and ≥500 IU/L. The infants' anti-HBVs-positive rate and titres were negatively correlated with maternal anti-HBVs titres: the anti-HBVs-positive rate of infants were 88.9% (360/405), 84.5% (381/451) and 77.3% (160/207) in mothers with low, intermediate and high antibody titres, respectively, P<.0001. Median titres of anti-HBVs (IU/L) among infants were 169.1, 141.0 and 79.4, respectively, P=.020. One hundred and sixty-two infants were negative for anti-HBVs after the standard vaccination, and 120 of 131 of these infants (91.6%) reached anti-HBVs positivity after the first "booster" dose. The maternal anti-HBVs titres did not significantly affect infant response to this booster. In summary, transplacental transfer of anti-HBVs occurs and high titres of maternal anti-HBVs may suppress the immune response of infants to the standard HBV vaccination. The current schedule of the 0, 1 and 6 month may not be the optimal choice of infants with anti-HBVs-positive mothers.

Resistance Assessment for Oxathiapiprolin in Phytophthora capsici and the Detection of a Point Mutation (G769W) in PcORP1 that Confers Resistance

The potential for oxathiapiprolin resistance in Phytophthora capsici was evaluated. The baseline sensitivities of 175 isolates to oxathiapiprolin were initially determinated and found to conform to a unimodal curve with a mean EC50 value of 5.61 × 10(-4) μg/ml. Twelve stable oxathiapiprolin-resistant mutants were generated by fungicide adaptation in two sensitive isolates, LP3 and HNJZ10. The fitness of the LP3-mutants was found to be similar to or better than that of the parental isolate LP3, while the HNJZ10-mutants were found to have lost the capacity to produce zoospores. Taken together these results suggest that the risk of P. capsici developing resistance to oxathiapiprolin is moderate. Comparison of the PcORP1 genes in the LP3-mutants and wild-type parental isolate, which encode the target protein of oxathiapiprolin, revealed that a heterozygous mutation caused the amino acid substitution G769W. Transformation and expression of the mutated PcORP1-769W allele in the sensitive wild-type isolate BYA5 confirmed that the mutation in PcORP1 was responsible for the observed oxathiapiprolin resistance. Finally diagnostic tests including As-PCR and CAPs were developed to detect the oxathiapiprolin resistance resulting from the G769W point mutation in field populations of P. capsici.

Insights into the adaptive response of the plant-pathogenic oomycete Phytophthora capsici to the fungicide flumorph

Phytophthora capsici is an important oomycete plant pathogen that causes significant losses worldwide. The carboxylic acid amide fungicide flumorph has shown excellent activity against oomycete plant pathogens. Despite its potential, there remains concern that the sexual reproduction of oomycete pathogens, which results in genetic recombination, could result in the rapid development of resistance to flumorph. The current study utilized an iTRAQ (isobaric tags for relative and absolute quantitation) based method to compare differences between the proteome of the parental P. capsici isolate PCAS1 and its sexual progeny S2-838, which exhibits significant resistance to flumorph. A total of 2396 individual proteins were identified, of these, 181 were considered to be associated with the adaptive response of P. capsici to flumorph. The subsequent bioinformatic analysis revealed that the adaptive response of P. capsici to flumorph was complex and regulated by multiple mechanisms, including utilising carbohydrate from the host environment to compensate for the cell wall stress induced by flumorph, a shift in energy generation, decreased amino acids biosynthesis, and elevated levels of proteins associated with the pathogen's response to stimulus and transmembrane transport. Moreover, the results of the study provided crucial data that could provide the basis for early monitoring of flumorph resistance in field populations of P. capsici.

AIM2 inflammasome is dispensable for the host defense against Pseudomonas aeruginosa infection

Respiratory tract infection with Pseudomonas aeruginosa is a major cause of hospital&mdash;acquired pneumonia in immune&mdash;compromised individuals. Lung infection with P. aeruginosa is often associated with production of various inflammatory cytokines including IL&mdash;1&#946;. Production of IL&mdash;1&#946; requires proteolytic cleavage by a multiprotein complex termed inflammasome. AIM2 inflammasome recognizes foreign cytosolic double stranded DNA. A role of AIM2 in P. aeruginosa infection has not been reported previously. In this study, we found that P. aeruginosa infection induced degradation of AIM2 protein in macrophages and induction of AIM2 mRNA expression in macrophages and in the lung of mice. Interestingly, P. aeruginosa infection induced a similar level of IL&mdash;1&#946;, IL&mdash;6 and TNF production in wild&mdash;type and AIM2&mdash;deficient mice. Similarly, no significant differences in bacterial clearance, neutrophil infiltration and NF&mdash;&#954;B activation were observed between wild&mdash;type and AIM2&mdash;deficient mice following P. aeruginosa lung infection. Our data suggest that AIM2 inflammasome is dispensable for the host defense against P. aeruginosa infection.

Competition between pyrimorph-sensitive and pyrimorph-resistant isolates of Phytophthora capsici

Phytophthora capsici causes significant losses to vegetable production worldwide. Pyrimorph, a new carboxylic acid amide fungicide, has been registered to control P. capsici in China. A mutation (Q1077K) in cellulose synthase 3 has been reported to confer resistance to pyrimorph. In this study, we measured the competition between pyrimorph-resistant and pyrimorph-sensitive isolates of P. capsici. Mixed zoospore suspensions of resistant (R) and sensitive (S) isolates at five ratios (1R:9S, 3R:7S, 5R:5S, 7R:3S, and 9R:1S) were applied to carrot agar in vitro test (with five successive transfers) and to the soil surface around pepper plants in planta test (with 10 successive disease cycles). The proportion of resistant isolates was measured by a conventional assay in which single zoospore isolates recovered after transfers or disease cycles were grown on agar medium with a discriminatory concentration of pyrimorph. The results were then compared with those of a real-time polymerase chain reaction (PCR)-based method developed here, the results were similar. Both assays showed that the competitive ability of the resistant isolates was similar to or less than that of the sensitive isolates. The real-time PCR assay developed will be useful for high-throughput analysis and monitoring the development of pyrimorph resistance in field populations of P. capsici.

Two non-target recessive genes confer resistance to the anti-oomycete microtubule inhibitor zoxamide in Phytophthora capsici

This study characterized isolates of P. capsici that had developed a novel mechanism of resistance to zoxamide, which altered the minimum inhibition concentration (MIC) but not the EC50. Molecular analysis revealed that the β-tubulin gene of the resistant isolates contained no mutations and was expressed at the same level as in zoxamide-sensitive isolates. This suggested that P. capsici had developed a novel non-target-site-based resistance to zoxamide. Analysis of the segregation ratio of zoxamide-resistance in the sexual progeny of the sensitive isolates PCAS1 and PCAS2 indicated that the resistance to zoxamide was controlled by one or more recessive nuclear genes. Furthermore, the segregation of resistance in the F1, F2, and BC1 progeny was in accordance with the theoretical ratios of the χ(2) test (P>0.05), which suggested that the resistance to zoxamide was controlled by two recessive genes, and that resistance to zoxamide occurred when at least one pair of these alleles was homozygous. This implies that the risk of zoxamide-resistance in P. capsici is low to moderate. Nevertheless this potential for resistance should be monitored closely, especially if two compatible mating types co-exist in the same field.

Spontaneous neuronal activity predicts intersubject variations in executive control of attention

Executive control of attention regulates our thoughts, emotion and behavior. Individual differences in executive control are associated with task-related differences in brain activity. But it is unknown whether attentional differences depend on endogenous (resting state) brain activity and to what extent regional fluctuations and functional connectivity contribute to individual variations in executive control processing. Here, we explored the potential contribution of intrinsic brain activity to executive control by using resting-state functional magnetic resonance imaging (fMRI). Using the amplitude of low-frequency fluctuations (ALFF) as an index of spontaneous brain activity, we found that ALFF in the right precuneus (PCUN) and the medial part of left superior frontal gyrus (msFC) was significantly correlated with the efficiency of executive control processing. Crucially, the strengths of functional connectivity between the right PCUN/left msFC and distributed brain regions, including the left fusiform gyrus, right inferior frontal gyrus, left superior frontal gyrus and right precentral gyrus, were correlated with individual differences in executive performance. Together, the ALFF and functional connectivity accounted for 67% of the variability in behavioral performance. Moreover, the strength of functional connectivity between specific regions could predict more individual variability in executive control performance than regionally specific fluctuations. In conclusion, our findings suggest that spontaneous brain activity may reflect or underpin executive control of attention. It will provide new insights into the origins of inter-individual variability in human executive control processing.

Loss of heterozygosity drives clonal diversity of Phytophthora capsici in China

Phytophthora capsici causes significant loss to pepper (Capsicum annum) in China and our goal was to develop single nucleotide polymorphism (SNP) markers for P. capsici and characterize genetic diversity nationwide. Eighteen isolates of P. capsici from locations worldwide were re-sequenced and candidate nuclear and mitochondrial SNPs identified. From 2006 to 2012, 276 isolates of P. capsici were recovered from 136 locations in 27 provinces and genotyped using 45 nuclear and 2 mitochondrial SNPs. There were two main mitochondrial haplotypes and 95 multi-locus genotypes (MLGs) identified. Genetic diversity was geographically structured with a high level of genotypic diversity in the north and on Hainan Island in the south, suggesting outcrossing contributes to diversity in these areas. The remaining areas of China are dominated by four clonal lineages that share mitochondrial haplotypes, are almost exclusively the A1 or A2 mating type and appear to exhibit extensive diversity based on loss of heterozygosity (LOH). Analysis of SNPs directly from infected peppers confirmed LOH in field populations. One clonal lineage is dominant throughout much of the country. The overall implications for long-lived genetically diverse clonal lineages amidst a widely dispersed sexual population are discussed.

Genetically diverse long-lived clonal lineages of Phytophthora capsici from pepper in Gansu, China

Phytophthora capsici causes significant loss to pepper production in China, and our objective was to investigate the population structure in Gansu province. Between 2007 and 2011, 279 isolates were collected from pepper at 24 locations. Isolates (or subsets) were assessed for simple sequence repeat (SSR) genotype, metalaxyl resistance, mating type, and physiological race using cultivars from the World Vegetable Center (AVRDC) and New Mexico recombinant inbred lines (NMRILs). The A1 and A2 mating types were recovered from nine locations and metalaxyl-resistant isolates from three locations. A total of 104 isolates tested on the AVRDC panel resolved five physiological races. None of 42 isolates tested on the NMRIL panel caused visible infection. SSR genotyping of 127 isolates revealed 59 unique genotypes, with 42 present as singletons and 17 having 2 to 13 isolates. Isolates with identical genotypes were recovered from multiple sites across multiple years and, in many cases, had different race types or metalaxyl sensitivities. Isolates clustered into three groups with each group having almost exclusively the A1 or A2 mating type. Overall it appears long-lived genetically diverse clonal lineages are dispersed across Gansu, outcrossing is rare, and functionally important variation exists within a clonal framework.

Resistance to the novel fungicide pyrimorph in Phytophthora capsici: risk assessment and detection of point mutations in CesA3 that confer resistance

Pyrimorph is a novel fungicide with high activity against the plant pathogen Phytophthora capsici. We investigated the risk that P. capsici can develop resistance to pyrimorph. The baseline sensitivities of 226 P. capsici isolates, tested by mycelial growth inhibition, showed a unimodal distribution with a mean EC(50) value of 1.4261 (± 0.4002) µg/ml. Twelve pyrimorph-resistant mutants were obtained by repeated exposure to pyrimorph in vitro with a frequency of approximately 1 × 10(-4). The resistance factors of the mutants ranged from 10.67 to 56.02. Pyrimorph resistance of the mutants was stable after 10 transfers on pyrimorph-free medium. Fitness in sporulation, cystospore germination, and pathogenicity in the pyrimorph-resistant mutants was similar to or less than that in the parental wild-type isolates. On detached pepper leaves and pepper plants treated with the recommended maximum dose of pyrimorph, however, virulence was greater for mutants with a high level of pyrimorph resistance than for the wild type. The results suggest that the risk of P. capsici developing resistance to pyrimorph is low to moderate. Among mutants with a high level of pyrimorph resistance, EC(50) values for pyrimorph and CAA fungicides flumorph, dimethomorph, and mandipropamid were positively correlated. This indicated that point mutations in cellulose synthase 3 (CesA3) may confer resistance to pyrimorph. Comparison of CesA3 in isolates with a high level of pyrimorph resistance and parental isolates showed that an amino acid change from glutamine to lysine at position 1077 resulted in stable, high resistance in the mutants. Based on the point mutations, an allele-specific PCR method was developed to detect pyrimorph resistance in P. capsici populations.

Assessing the risk that Phytophthora melonis can develop a point mutation (V1109L) in CesA3 conferring resistance to carboxylic acid amide fungicides

The risk that the plant pathogen Phytophthora melonis develops resistance to carboxylic acid amide (CAA) fungicides was determined by measuring baseline sensitivities of field isolates, generating resistant mutants, and measuring the fitness of the resistant mutants. The baseline sensitivities of 80 isolates to flumorph, dimethomorph and iprovalicarb were described by unimodal curves, with mean EC(50) values of 0.986 (±0.245), 0.284 (±0.060) and 0.327 (±0.068) µg/ml, respectively. Seven isolates with different genetic background (as indicated by RAPD markers) were selected to generate CAA-resistance. Fifty-five resistant mutants were obtained from three out of seven isolates by spontaneous selection and UV-mutagenesis with frequencies of 1×10(-7) and 1×10(-6), respectively. CAA-resistance was stable for all mutants. The resistance factors of these mutants ranged from 7 to 601. The compound fitness index (CFI  =  mycelial growth × zoospore production × pathogenicity) was often lower for the CAA-resistant isolates than for wild-type isolates, suggesting that the risk of P. melonis developing resistance to CAA fungicides is low to moderate. Among the CAA-resistant isolates, a negative correlation between EC(50) values was found for iprovalicarb vs. flumorph and for iprovalicarb vs. dimethomorph. Comparison of the full-length cellulose synthase 3 (CesA3) between wild-type and CAA-resistant isolates revealed only one point mutation at codon position 1109: a valine residue (codon GTG in wild-type isolates) was converted to leucine (codon CTG in resistant mutants). This represents a novel point mutation with respect to mutations in CesA3 conferring resistance to CAA fungicides. Based on this mutation, an efficient allelic-specific PCR (AS-PCR) method was developed for rapid detection of CAA-resistance in P. melonis populations.

Dark pixel intensity determination and its applications in normalizing different exposure time and autofluorescence removal

The purpose of this study is to investigate how to scale pixel intensity acquired from one exposure time to another. This is required when comparing grayscale images acquired at different exposure times and other image processing such as autofluorescence removal. Pixel intensity is linear to exposure time as long as images are acquired at the linear range of a camera, but importantly there exists an intercept, which is set by the camera. We termed this intercept as dark pixel intensity, as it is the pixel intensity under conditions of no light and zero exposure time. Dark pixel intensity is determined by camera's readout noise (electron/pixel), gain, and DC offset. Knowing dark pixel intensity, image acquired from one exposure time can be linearly scaled to an image at a different exposure time. Dark pixel intensity can be directly measured by obtaining an image at no light and zero (or minimum) exposure time. It can be also indirectly calculated by capturing images at a series of exposure times. Finally, the prestained and poststained images were acquired at their optimal exposures and autofluorescence was completely removed by normalizing images with the exposure time ratio and dark pixel intensity followed by subtraction.

Multivariate modelling of endophenotypes associated with the metabolic syndrome in Chinese twins

AIMS/HYPOTHESIS

The common genetic and environmental effects on endophenotypes related to the metabolic syndrome have been investigated using bivariate and multivariate twin models. This paper extends the pairwise analysis approach by introducing independent and common pathway models to Chinese twin data. The aim was to explore the common genetic architecture in the development of these phenotypes in the Chinese population.

METHODS

Three multivariate models including the full saturated Cholesky decomposition model, the common factor independent pathway model and the common factor common pathway model were fitted to 695 pairs of Chinese twins representing six phenotypes including BMI, total cholesterol, total triacylglycerol, fasting glucose, HDL and LDL. Performances of the nested models were compared with that of the full Cholesky model.

RESULTS

Cross-phenotype correlation coefficients gave clear indication of common genetic or environmental backgrounds in the phenotypes. Decomposition of phenotypic correlation by the Cholesky model revealed that the observed phenotypic correlation among lipid phenotypes had genetic and unique environmental backgrounds. Both pathway models suggest a common genetic architecture for lipid phenotypes, which is distinct from that of the non-lipid phenotypes. The declining performance with model restriction indicates biological heterogeneity in development among some of these phenotypes.

CONCLUSIONS/INTERPRETATION

Our multivariate analyses revealed common genetic and environmental backgrounds for the studied lipid phenotypes in Chinese twins. Model performance showed that physiologically distinct endophenotypes may follow different genetic regulations.

A neural network method for detection of obstructive sleep apnea and narcolepsy based on pupil size and EEG

Electroencephalogram (EEG) is able to indicate states of mental activity ranging from concentrated cognitive efforts to sleepiness. Such mental activity can be reflected by EEG energy. In particular, intrusion of EEG theta wave activity into the beta activity of active wakefulness has been interpreted as ensuing sleepiness. Pupil behavior can also provide information regarding alertness. This paper develops an innovative signal classification method that is capable of differentiating subjects with sleep disorders which cause excessive daytime sleepiness (EDS) from normal control subjects who do not have a sleep disorder based on EEG and pupil size. Subjects with sleep disorders include persons with untreated obstructive sleep apnea (OSA) and narcolepsy. The Yoss pupil staging rule is used to scale levels of wakefulness and at the same time theta energy ratios are calculated from the same 2-s sliding windows by Fourier or wavelet transforms. Then, an artificial neural network (NN) of modified adaptive resonance theory (ART2) is utilized to identify the two groups within a combined group of subjects including those with OSA and healthy controls. This grouping from the NN is then compared with the actual diagnostic classification of subjects as OSA or controls and is found to be 91% accurate in differentiating between the two groups. The same algorithm results in 90% correct differentiation between narcoleptic and control subjects.

[In vitro modulation of the invasive and metastatic potentials of human hepatocellular carcinoma by interlukin-2]

OBJECTIVE

To investigate the effects of interlukin-2 (IL-2) on the in vitro invasiveness and the expression of several cell surface antigens related to invasive and metastatic potentials of human hepatocellular carcinoma (HCC) QGY-7701 cell line.

METHODS

QGY-7701 cells were incubated with high concentration of IL-2 or low concentration of IL-2 in different time. The expression of ICAM-1, CD(44) and HLA-I of the tumor cells was determined by fluorescence-activated cell sorter (FACS) analysis The tumor cell binding affinity to extracellular matrix components was measured by cell attachment assay. The degree of homotypic aggregation was quantified by cell aggregation assay.

RESULTS

IL-2 treatment exhibited enhanced expression of ICAM-1 (from 8.3% to 20.5% after high concentration of IL-2 treatment and 17.3% after low concentration of IL-2 treatment) and HLA-I (from 9.8% to 25.4% and 22.1%, respectively after high and low concentration of IL-2 treatment), suppression of CD(44) (from 26.4% to 12.5% and 11.6%, respectively) on HCC cell line and decreased binding affinity to type IV collagen (from 23.5% to 12.4%, 32.3% to 13.8%, 45.7% to 19.6% at 20 min, 40 min and 60 min, respectively after high concentration of IL-2 treatment, and 9.6%, 12.5% and 17.9%, respectively after low concentration of IL-2 treatment) and fibronectin (from 18.6% to 14.1%, 31.2% to 18.4%, 44.5% to 20.5% at 20 min, 40 min and 60 min, respectively after high concentration of IL-2 treatment, and 14.6%, 17.1% and 18.9%, respectively after low concentration of IL-2 treatment) and the degree of homotypic aggregation (from 58.3% to 26.5%, 85.4% to 37.6%, 88.6% to 42.3% at 20 min, 40 min and 60 min, respectively after high concentration of IL-2 treatment, and 25.0%, 36.4% and 42.6%, respectively after low concentration of IL-2 treatment)of HCC cells.

CONCLUSIONS

IL-2 may directly alter tumor properties associated with invasive and metastatic phenotypes of HCC cells, and can inhibit the invasive and metastatic potentials of HCC cells.

Differential changes of synaptic transmission in spiny neurons of rat neostriatum following transient forebrain ischemia

Spiny neurons in neostriatum are vulnerable to cerebral ischemia. To reveal the mechanisms underlying the postischemic neuronal damage, the spontaneous activities, evoked postsynaptic potentials and membrane properties of spiny neurons in rat neostriatum were compared before and after transient forebrain ischemia using intracellular recording and staining techniques in vivo. In control animals the membrane properties of spiny neurons were about the same between the left and right neostriatum but the inhibitory synaptic transmission was stronger in the left striatum. After severe ischemia, the spontaneous firing and membrane potential fluctuation of spiny neurons dramatically reduced. The cortically evoked initial excitatory postsynaptic potentials were suppressed after ischemia indicated by the increase of stimulus threshold and the rise time of these components. The paired-pulse facilitation test indicated that such suppression might involve presynaptic mechanisms. The inhibitory postsynaptic potentials in spiny neurons were completely abolished after ischemia and never returned to the control levels. A late depolarizing postsynaptic potential that was elicited from approximately 5% of the control neurons by cortical stimulation could be evoked from approximately 30% of the neurons in the left striatum and approximately 50% in the right striatum after ischemia. The late depolarizing postsynaptic potential could not be induced after acute thalamic transection. The intrinsic excitability of spiny neurons was suppressed after ischemia evidenced by the significant increase of spike threshold and rheobase as well as the decrease of repetitive firing rate following ischemia. The membrane input resistance and time constant increased within 6 h following ischemia and the amplitude of fast afterhyperpolarization significantly increased after ischemia. These results indicate the depression of excitatory monosynaptic transmission, inhibitory synaptic transmission and excitability of spiny neurons after transient forebrain ischemia whereas the excitatory polysynaptic transmission in neostriatum was potentiated. The facilitation of excitatory polysynaptic transmission is stronger in the right neostriatum than in the left neostriatum after ischemia. The suppression of inhibitory component and the facilitation of excitatory polysynaptic transmission may contribute to the pathogenesis of neuronal injury in neostriatum after transient cerebral ischemia.

Enhanced excitatory synaptic transmission in spiny neurons of rat striatum after unilateral dopamine denervation

The synaptic transmission and intrinsic membrane properties of spiny neurons in rat neostriatum were studied after unilateral dopamine depletion using in vivo intracellular recording and staining techniques. Two to four weeks after dopamine denervation, the spontaneous firing rate of spiny neurons increased and the spontaneous membrane potential fluctuation stayed at a more depolarized state for longer periods of time. The amplitude of cortically evoked initial excitatory postsynaptic potentials increased and a late excitatory postsynaptic potential that was occasionally found in control neurons was elicited from 23% of spiny neurons after dopamine denervation. No significant changes in intrinsic membrane properties of spiny neurons were observed after dopamine denervation. These results suggest that dopamine inhibits excitatory synaptic transmission of spiny neurons in naïve animals.

[Purification and characterization of 2-carbonyl reductase from marine bacteria Bacillus sp]

ANADPH-dependent 2-Oxoaldehyde reductase was isolated and purified from a marine bacteria Bacillus sp. The purification procedure involved ammonium sulfate fractionation and Q Sepharose FF, Hydroxyapatite, Sephadex G-100 column chromatographies. The specific activity of the purified enzyme was increased by 141.1 folds over crude extract and the recovery yield was 11.4%. 2-Oxoaldehyde compounds were found to be speciall good substrates. The optimum pH of the enzyme activity was 6.2-6.6. The Km coefficient for 3-deoxyglucosone was 2.5 mmol/L. The molecular weight of the enzyme was estimated to be 33 kD The enzyme activity is stable below 30 degrees C and pH 5.0-8.0. EDTA, beta-mercaptoethanol and dithiothreitol enhanced the enzyme activity. On the other hand, the enzyme activity was partially lost by idoacetic acid or N-ethylmaleimide.

[A histopathologic and immunohistochemical study of 68 cases of hemangioblastoma]

The aim of this study was to evaluate the histologic characteristics of hemangioblastoma (HB) and investigate the histogenesis of its stromal cells. Sixty-eight cases of hemangioblastoma were studied by light microscopy and thirty-three cases were examined by immunohistochemical stainning. Forty-eight of the 68 patients were males and 20 were females. The average age was 37. Fifty-two cases (76.6%) had been present for two months to one year before the diagnosis was made. Sixty cases (88.2%) arose in the cerebellum. Fifty cases (73.5%) appeared as cystic nodules. Histologically, the 68 cases of HB were further categorized into three subtypes: typical (30 cases), cellular (21 cases) and reticular (17 cases). In 33 cases, the stromal cell were positive for NSE, but negative for F-VIII, UEA-1, GFAP and EMA. In summary, there are three essential histologic categories of hemangioblastoma, and its stromal cells may well have the characters of neuroendocrine differentiation.

Cbln3, a novel member of the precerebellin family that binds specifically to Cbln1

Precerebellin (Cbln1) is the precursor of the brain-specific hexadecapeptide cerebellin. Although cerebellin has properties of a conventional neuropeptide, its function is controversial because Cbln1 has structural features characteristic of circulating atypical collagens. Cbln1 is related to the three subunits of the complement C1q complex. Therefore, we hypothesized that Cbln1 participated in analogous heteromeric complexes with precerebellin-related proteins. Using LexA-Cbln1 as bait in a yeast two-hybrid screen, we isolated a cDNA encoding a novel Cbln1-related protein, designated Cbln3. The gene encoding cbln3 had the same intron-exon structure as cbln1 but mapped to a different mouse chromosome (14). The deduced amino acid sequence of Cbln3 was 55% identical to Cbln1 and also contained a C1q signature domain and signal sequence for secretion. In addition to binding avidly to Cbln3, Cbln1 also formed homomeric complexes. In contrast, Cbln3 homomeric association was weak. These interactions exhibited specificity because C1qB bound to neither Cbln1 nor Cbln3. Like cbln1, cbln3 was expressed in the cerebellum and dorsal cochlear nucleus in which it was detected in granule neurons. Because Cbln1 and Cbln3 are coexpressed in the brain and interact avidly, they may function as a secreted heteromeric complex in vivo.

The effect of coriaria lactone on NMDA receptor mediated currents in rat hippocampal CA1 neurons

To investigate the exact mechanism of epileptogenesis induced by coriaria lactone (CL), the effect of CL on NMDA receptor mediated current (IAsp) in rat hippocampal CA1 neurons was investigated by using nystatin perforated whole-cell patch clamp. 10(-6)-10(-4) mol/L Asp acted on NMDA receptors and elicited an inward current (IAsp) at a holding potential (VH) of -40 mV in presence of 10(-6) mol/L glycine and absence of Mg2+ extracellularly. CL enhanced NMDA receptor mediated current induced by Asp, but had no effect on threshold concentration, EC50, Hill coefficient as well as maximal-effect concentration and reversal potential of IAsp. The effect had no relationship with holding potential. These results showed that CL could enhance NMDA receptor mediated current to increase [Ca2+]i of neurons by acting on Gly site, thereby inducing epilepsy.