[Impact of different diagnostic criteria for assessing mild micro-hepatic encephalopathy in liver cirrhosis: an analysis based on a prospective, multicenter, real-world study]

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.

[Effect of Liraglutide on platelet distribution width and carotid intima-media thickness in type 2 diabetic mellitus patients with obesity]

Objective: To investigate the effect of Liraglutide on platelet distribution width(PDW) and carotid intima-media thickness(cIMT) in type 2 diabetic mellitus patients with obesity. Methods: Randomized controlled trial. A total of 80 type 2 diabetes mellitus (T2DM) obese patients with unsatisfactory glucose control were prospectively enrolled in this study from the Department of Endocrinology of Yuhuangding Hospital Affiliated to Qingdao University from January to December 2021. All the participants were treated with metformin or sulfonylureas. They were randomly divided into two groups: Liraglutide treatment group (Li group, n=40) and Control group (Con group, n=40).The Li group started the treatment with Liraglutide on the basis of the original hypoglycemic agents and the Con group was treated with metformin and sulfonylurea. After 16 weeks of treatment, the changes of PDW, cIMT and body mass index (BMI) in the two groups were observed, multiple linear regression was uesd to analyze the influencing factors of cIMT variation, and the effect of liraglutide on PDW and cIMT in obese patients with type 2 diabetes was analyzed. Results: Finally, 38 patients completed the study in Li group, including 23 males and 15 females, aged 30-69(56±11) years. All 40 patients in Con group completed the study, including 18 males and 22 females, aged 39-67(59±7) years. After 16 weeks of treatment, the levels of PDW and cIMT in Li group were (12.8±1.6) fl and (0.85±0.08) mm, respectively, lower than those before treatment (15.0±1.6) fl and (1.14±0.10) mm (t=18.61 and 20.37, respectively, both P<0.001); The PDW and cIMT in Con group were (13.6±1.5) fl and (1.05±0.10) mm, respectively, lower than those before treatment (15.0±1.5) fl and (1.13±0.13) mm (t=17.42 and 9.65, respectively, both P<0.001). The levels of fasting plasma glucose (FPG) and total cholesterol (TC) in both groups were lower than those before treatment(all P<0.001). After the treatment, the levels of PDW, cIMT, FPG and TC in Li group were lower than those in Con group (all P<0.05). The changes of PDW and cIMT before and after the treatment in Li group were (2.2±0.7) fl and (0.30±0.09) mm, respectively, higher than those in the Con group [(1.4±0.5) fl and (0.09±0.06) mm], with a statistically significant difference (both P<0.001). The changes of FPG and TC in Li group were significantly higher than those in Con group (all P<0.05). Multiple linear regression analysis showed that liraglutide, the changes of TC and systolic blood pressure (SBP) were the influencing factors for the changes of cIMT [β (95%CI) were 0.20 (0.17-0.23), 0.03 (0.01-0.06), 0.01 (0.00-0.01), respectively, all P<0.05] Conclusion: Liraglutide treatment could reduce PDW and cIMT, thus contributing to cardiovascular benefits.

Nirmatrelvir increases blood tacrolimus concentration in COVID-19 patients as determined by UHPLC-MS/MS method

OBJECTIVE

Transplant recipients have a higher risk of SARS-CoV-2 infection owing to the use of immunosuppressive drugs like tacrolimus (FK506). FK506 and nirmatrelvir (NMV) (an anti-SARS-CoV-2 drug) are metabolized by cytochrome P450 3A4 and may have potential drug-drug interactions. It is important to determine the effect of NMV on FK506 concentrations.

PATIENTS AND METHODS

Following protein precipitation from blood, FK506 and its internal standard (FK506-13C,2d4) were detected by ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS). Total 22 blood samples (valley concentrations) from two coronavirus disease 2019 (COVID-19) patients were collected and analyzed for FK506 concentrations.

RESULTS

Blood levels of FK506 (0.5-100 ng/mL) showed good linearity. The UHPLC-MS/MS method was validated with intra- and inter-batch accuracies of 104.55-107.85%, and 99.52-108.01%, respectively, and precisions of < 15%. Mean blood FK506 concentration was 12.01 ng/mL (range, 3.15-33.1 ng/mL). Five-day co-administration with NMV increased the FK506 concentrations from 3.15 ng/mL to 33.1 ng/mL, returning to 3.36 ng/mL after a 9-day-washout.

CONCLUSIONS

We developed a simple quantification method for therapeutic drug monitoring of FK506 in patients with COVID-19 using UHPLC-MS/MS with protein precipitation. We found that NMV increased FK506 blood concentration 10-fold. Therefore, it is necessary to re-consider co-administration of FK506 with NMV.

Long non-coding RNA SNHG15 indicates poor prognosis of non-small cell lung cancer and promotes cell proliferation and invasion

OBJECTIVE

To investigate the expression of human long non-coding ribonucleic acid (RNA) small nucleolar RNA host gene 15 (SNHG15) in non-small cell lung cancer (NSCLC) tissues and its prognostic significance, and to study the influencing mechanism of SNHG15 on biological functions in lung cancer cell lines.

PATIENTS AND METHODS

The expression levels of SNHG15 in 49 pairs of lung cancer tissues and para-carcinoma tissues were detected via quantitative real-time polymerase chain reaction (qRT-PCR). The lung cancer cells were transiently transfected with small-interfering (si)-SNHG15 using RNA interference technique. The effect of si-SNHG15 on the proliferation of lung cancer cells was observed via methyl thiazolyl tetrazolium (MTT) assay, its effect on apoptosis of A549 cells was detected via Hoechst 33342 staining and flow cytometry, and its effects on invasion and migration of A549 cells were studied via wound healing assay and transwell assay.

RESULTS

Results of qRT-PCR showed that the expression of SNHG15 in cancer tissues was increased compared with that in para-carcinoma tissues. Results of cell counting kit-8 (CCK-8) assay showed that knocking down SNHG15 could significantly inhibit the proliferation of lung cancer A549 cells. Hoechst 33342 staining and flow cytometry revealed that knocking down SNHG15 could significantly promote apoptosis of A549 cells. Wound healing assay and transwell assay revealed that knocking down SNHG15 could significantly inhibit the invasion and metastasis capacities of lung cancer A549 cells. Results of Western blotting showed that knocking down SNHG15 could inhibit the invasion and metastasis of A549 cells through inhibiting the expressions of epithelial-mesenchymal transition (EMT), matrix metalloproteinase-2 (MMP-2) and MMP-9 in cells.

CONCLUSIONS

The expression of SNHG15 in lung cancer tissues is significantly higher than that in para-carcinoma tissues, the prognosis of patients accompanied with a high expression of SNHG15 is poor, and knockdown of SNHG15 in A549 cells can inhibit cell proliferation, invasion, and metastasis, and promote apoptosis.

Metformin improves the glucose and lipid metabolism via influencing the level of serum total bile acids in rats with streptozotocin-induced type 2 diabetes mellitus

OBJECTIVE

To study the effects of metformin on streptozotocin-induced type 2 diabetes mellitus (T2DM) in rats.

MATERIALS AND METHODS

Wistar male rats were divided into two groups: standard diet (SD, n = 20) group and high-fat diet (HFD, n = 80) group. Twenty rats in HFD group were randomly treated with metformin (EI group). After 6 weeks, among rats in HFD group, 20 rats were intraperitoneally injected with citrate buffered saline (IR group), 20 rats treated with metformin per day for 4 weeks (LI group), and 20 rats were given nothing (DM group). Rats in SD group were injected with citrate buffered saline as normal control (NC) group. Moreover, streptozotocin (STZ) was used for inducing diabetes. The metabolic parameters, such as body weight, fasting blood glucose (FBG), fasting insulin concentration (FINS), total cholesterol (TC), total triglycerides (TG), low-density lipoprotein cholesterol (LDLC) and total bile acid (TBA) were measured.

RESULTS

Compared with SD group, the levels of body weight, FBG, TC, LDLC, TBA and FINS and AUC (glucose) were significantly higher in HFD group. After administration of metformin, the levels of FBG, TG, TC, LDLC and TBA in DM and LI group were higher than NC group. Besides, the FBG, TG, TC, TBA and LDLC levels in EI group were higher than DM group.

CONCLUSIONS

Metformin may help to improve the glucose and lipid metabolism by influencing the level of serum total bile acids. A combination of HFD and metformin could be effective in the treatment of rats with T2DM.

Fluoroscopy-guided gastric peroral endoscopic pyloromyotomy (G-POEM): a more reliable and efficient method for treatment of refractory gastroparesis

INTRODUCTION

Prior studies show promising results of the gastric peroral endoscopic pyloromyotomy (G-POEM) procedure for treatment of refractory gastroparesis. One major technical challenge involved in this procedure is identifying the pyloric muscular ring (PMR). The aim of this study is to establish a reliable method for identification of the PMR during G-POEM.

METHODS

Fluoroscopy-guided G-POEM was performed by placing an endoclip at the 9 to 11'o clock position at the pylorus for identification of PMR. Conventional G-POEM was performed by observation of blue colored mucosa at the pylorus area as an indirect marker for PMR. The degree of the PMR identification was graded into well identified, identified, and not identified based on the appearance of the PMR. Procedure times were accurately documented. Gastroparesis cardinal symptoms index and gastric emptying scintigraphy were evaluated before and after the procedure.

RESULTS

Fourteen patients were studied, seven underwent fluoroscopy-guided G-POEM, and seven patients underwent conventional G-POEM. All procedures achieved technical success and no adverse events occurred. In the seven patients who underwent fluoroscopy-guided G-POEM, the PMR was well identified in four patients and identified in three patients. In the seven patients who underwent conventional G-POEM, the PMR was identified in four patients and not identified in three patients. The average time to complete the fluoroscopy-guided G-POEM was significantly shorter than that of the conventional G-POEM.

CONCLUSIONS

Fluoroscopy-guided G-POEM by placement of an endoclip at the pylorus was a reliable and safe method to direct the orientation of the submucosal tunnel, to facilitate the location of the PMR, and to shorten the procedure time.

Macrophage Phenotype in Liver Injury and Repair

Macrophages hold a critical position in the pathogenesis of liver injury and repair, in which their infiltrations is regarded as a main feature for both acute and chronic liver diseases. It is noted that, based on the distinct phenotypes and origins, hepatic macrophages are capable of clearing pathogens, promoting/or inhibiting liver inflammation, while regulating liver fibrosis and fibrolysis through interplaying with hepatocytes and hepatic stellate cells (HSC) via releasing different types of pro- or anti-inflammatory cytokines and growth factors. Macrophages are typically categorized into M1 or M2 phenotypes by adapting to local microenvironment during the progression of liver injury. In most occasions, M1 macrophages play a pro-inflammatory role in liver injury, while M2 macrophages exert an anti-inflammatory or pro-fibrotic role during liver repair and fibrosis. In this review, we focused on the up-to-date information about the phenotypic and functional plasticity of the macrophages and discussed the detailed mechanisms through which the phenotypes and functions of macrophages are regulated in different stages of liver injury and repair. Moreover, their roles in determining the fate of liver diseases were also summarized. Finally, the macrophage-targeted therapies against liver diseases were also be evaluated.

Up-regulation of the Ang II/AT1 receptor may compensate for the loss of gastric antrum ICC via the PI3k/Akt signaling pathway in STZ-induced diabetic mice

The classic renin-angiotensin system (RAS) is a complex system in which angiotensin II (Ang II) has been identified as an important endogenous regulator that influences both smooth muscle contraction and cell growth. Although a local RAS is known to exist in the gastrointestinal tract, it is unclear whether Ang II is involved in the loss of gastric interstitial cells of Cajal (ICC) in diabetic mice. The present study was designed to investigate the effect of Ang II on ICC survival in streptozotocin (STZ)-induced diabetic mice. Western blot, immunofluorescence, isometric muscle recording, enzyme-linked immunosorbent assay (ELISA) and a cell counting kit-8 were used in this research. Our results demonstrate that the c-Kit and membrane-bound stem cell factor (mSCF) protein expression levels in gastric smooth muscle were decreased in STZ-induced diabetic mice. However, the angiotensin receptor type 1 (AT1R) expression levels in gastric smooth muscle and angiotensin-converting enzyme (ACE) expression levels in gastric mucosa were increased. The effect of Ang II on the tonic contraction of gastric smooth muscle was potentiated in diabetic mice, and the plasma Ang II level was enhanced. Ang II increased mSCF expression, cell proliferation, and Akt-Ser473 phosphorylation in cultured gastric smooth muscle cells (GSMCs). These effects were reduced by specific inhibitors ZD7155 (an AT1R antagonist) and LY294002 (a PI3-kinase inhibitor). Our results suggest that Ang II increases mSCF expression and cell proliferation in cultured GSMCs in a PI3K/Akt signaling-dependent manner. ACE and AT1R up-regulation in the stomach may help compensate for ICC loss in STZ-induced diabetic mice.

Effect of exemestane on the invasive growth of endometrial carcinoma HHUA cells

OBJECTIVE

To investigate the effect of exemestane on HHUA human endometrial carcinoma cells.

MATERIALS AND METHODS

The HHUA human endometrial carcinoma cells were treated with various concentrations of exemestane, and its effects on cell growth and apoptosis were investigated in vitro. The cell apoptosis was analyzed by flow cytometry and RT-PCR was used to investigate the expression of CD44s. The invasion ability of HHUA human endometrial carcinoma cells which treated with exemestane were assessed using transwell chamber model.

RESULTS

At increasing doses of exemestane, a simultaneous increase in apoptotic subpopulations was detected when compared with group A (p < 0.05); the CD44s expression was found to be suppressed after the exemestane treatment. The decrease was a dose-dependent with exemestane treatment.

CONCLUSION

6x10⁸ mol/L exemestane is an optimal dose to inhibit the expression of CD44s mRNA and inhibit the invasive growth of the endometrial carcinoma HHUA cells.

Magnetic bead and gold nanoparticle probes based immunoassay for β-casein detection in bovine milk samples

In this work, a double-probe based immunoassay was developed for rapid and sensitive determination of β-casein in bovine milk samples. In the method, magnetic beads (MBs), employed as supports for the immobilization of anti-β-casein polyclonal antibody (PAb), were used as the capture probe. Colloidal gold nanoparticles (AuNPs), employed as a bridge for loading anti-β-casein monoclonal antibody (McAb) and horseradish peroxidase (HRP), were used as the amplification probe. The presence of β-casein causes the sandwich structures of MBs-PAb-β-casein-McAb-AuNPs through the interaction between β-casein and the anti-β-casein antibodies. The HRP, used as an enzymatic-amplified tracer, can catalytically oxidize the substrate 3,3',5,5'-tetramethylbenzidine (TMB), generating optical signals that are proportional to the quantity of β-casein. The linear range of the immunoassay was from 6.5 to 1520ngmL(-1). The limit of detection (LOD) was 4.8ngmL(-1) which was 700 times lower than that of MBs-antibody-HRP based immunoassay and 6-7 times lower than that from the microplate-antibody-HRP based assay. The recoveries of β-casein from bovine milk samples were from 95.0% to 104.3% that had a good correlation coefficient (R(2)=0.9956) with those obtained by an official standard Kjeldahl method. For higher sensitivity, simple sample pretreatment and shorter time requirement of the antigen-antibody reaction, the developed immunoassay demonstrated the viability for detection of β-casein in bovine milk samples.

Exogenous H2 S enhances mice gastric smooth muscle tension through S-sulfhydration of KV 4.3, mediating the inhibition of the voltage-dependent potassium current

BACKGROUND

Hydrogen sulfide (H2 S) has been shown to have an excitatory effect on gastric motility, but the underlying molecular mechanism is unclear. In this study, we aimed to investigate the possible targets of H2 S and determine how H2 S affects its target proteins during H2 S-induced contraction.

METHODS

Patch-clamp and potentiometric fluorescence dye were utilized to measure the electrophysiological changes. The Biotin-switch assay was utilized to detect the protein S-sulfhydration. The isometric tension measurement was conducted too.

KEY RESULTS

Exogenous H2 S enhanced the tonic contraction of gastric antral smooth muscle, and voltage-dependent potassium channel (KV ) blocker and Dithiothreitol (DTT, a reducing agent) abolished the excitatory effect of NaHS. Exogenous H2 S inhibited the fast inactivation component of the voltage-dependent potassium channel current (IKVfast ) in isolated gastric antral smooth muscle cells. H2 S inhibited the KV 4.3 current in H293 cells with heterologous expression of KV 4.3, but did not inhibit the KV 4.1 and KV 4.2 currents, which together contribute greatly to IKVfast . NaHS significantly decreased the membrane potential in cultured gastric smooth muscle cells, but the NaHS-induced depolarization was suppressed by knockdown of KV 4.3 and N-ethylamaleimide (NEM), a free thiol group blocker. In addition, NaHS sulfhydrated KV 4.3 in H293 cells and in gastric smooth muscle tissue. However, this S-sulfhydration was inhibited by NEM and DTT. Meanwhile the NaHS-induced inhibition of IKVfast and KV 4.3 was also blocked by NEM and DTT.

CONCLUSIONS & INFERENCES

These results suggest that exogenous H2 S sulfhydrates KV 4.3 to decrease the membrane potential, thereby enhancing the basal tension of gastric antral smooth muscle.

A rapid immunomagnetic beads-based immunoassay for the detection of β-casein in bovine milk

An immunomagnetic beads-based enzyme-linked immunosorbent assay (IMBs-ELISA) was developed for the detection of β-casein in bovine milk. Immunomagnetic beads (IMBs) were employed as the solid phase. The anti-β-casein monoclonal antibody (McAb) bound to IMBs was used as capture probe and an anti-β-casein polyclonal antibody (PcAb), labelled with horseradish peroxidase (HRP), was employed as detector probe. Three reaction and two washing steps were needed. Each reaction needed 10 min or less, which significantly shortened detection compared with classic sandwich ELISA. β-Casein in bovine milk was detected across a linear range (2-128 μg mL(-1)). Application results were in accordance with the Kjejdahl method, which suggests the IMBs-ELISA is rapid and reliable for the detection of β-casein in bovine milk.

miR-21 is a key therapeutic target for renal injury in a mouse model of type 2 diabetes

AIMS/HYPOTHESIS

As microRNA-21 (miR-21) plays a pathological role in fibrosis, we hypothesised that it may be a therapeutic target for diabetic nephropathy.

METHODS

Abundance of miR-21 was examined in diabetic kidneys from db/db mice. The therapeutic potential of miR-21 in diabetic kidney injury was examined in db/db mice by an ultrasound-microbubble-mediated miR-21 small hairpin RNA transfer. In addition, the role and mechanisms of miR-21 in diabetic renal injury were examined in vitro under diabetic conditions in rat mesangial and tubular epithelial cell lines by overexpressing or downregulating miR-21.

RESULTS

In db/db mice, a mouse model of type 2 diabetes, renal miR-21 at age 20 weeks was increased twofold compared with db/m (+) mice at the same age, and this increase was associated with the development of microalbuminuria and renal fibrosis and inflammation. More importantly, gene transfer of miR-21 knockdown plasmids into the diabetic kidneys of db/db mice at age 10 weeks significantly ameliorated microalbuminuria and renal fibrosis and inflammation at age 20 weeks, revealing a therapeutic potential for diabetic nephropathy by targeting miR-21. Overexpression of miR-21 in kidney cells enhanced, but knockdown of miR-21 suppressed, high-glucose-induced production of fibrotic and inflammatory markers. Targeting Smad7 may be a mechanism by which miR-21 regulates renal injury because knockdown of renal miR-21 restored Smad7 levels and suppressed activation of the TGF-β and NF-κB signalling pathways.

CONCLUSIONS/INTERPRETATION

Inhibition of miR-21 might be an effective therapy for diabetic nephropathy.

Involvement of mitogen-activated protein kinase activation in cyclooxygenase-2 and transforming growth factor-β production in alveolar macrophage from chronic bronchitis rats

OBJECTIVE

Lipopolysaccharides (LPS) activates several signaling pathways in macrophages including mitogen-activated protein kinases (MAPK). Previous studies have investigated effect of LPS on MAPK activation in macrophage of normal rats. In the current study, we investigated the effect of LPS exposure on activation of MAPK in alveolar macrophage (AM) of chronic bronchitis (CB) rats and researched the corresponding cyclooxygenase-2 (COX-2), prostaglandins-2 (PGE(2)) and transforming growth factor- β (TGF-β) production and their MAPK signal pathways.

METHODS

CB model was established by injection of Bacillus Calmette-Guerin (BCG) and LPS in rats. Special inhibitors of p38, extracellular signal-regulated kinase (ERK) and c-Jun-N-terminal kinases (JNK) MAPK signal pathways were used to determine the effect of MAPK activation on COX-2, PGE(2), TGF-β production in AM of CB rats via RT-PCR, western blotting, radioimmunoassay and ELISA.

KEY FINDINGS

Synthesis of PGE(2) from AM of CB rats was increased and suppressed by either PD98059 or SB203580. SB203580 and PD98059, (inhibitors of ERK and p38 MAPK), could significantly inhibit COX-2 mRNA and protein expression. Moreover, ERK and p38 MAPK had synergistic effect on COX-2 expression. Inhibitor of ERK MAPK signal transduction could inhibit TGF-β expression in AM.

CONCLUSION

These results demonstrated COX-2, PGE(2) and TGF-β productions in AM of CB rats were significantly increased, which might be regulated by the different MAPK signaling pathway.

Effects of visfatin on proliferation and collagen synthesis in rat cardiac fibroblasts

The proliferation of cardiac fibroblasts (CFs) and excessive extracellular matrix protein accumulation are the basic pathological processes of myocardial fibrosis. Visfatin is a novel adipokine involved in the regulation of inflammatory cytokines, however, the effects of visfatin on proliferation and collagen synthesis of CFs are unclear. The aim of this study was to determine whether visfatin has any effect on the proliferation and collagen synthesis in rat CFs. Incorporation of [ (3)H]-thymidine and [ (3)H]-proline were used for evaluating DNA and collagen synthesis. Flow cytometry techniques were adopted to analyze cell cycle. Enzyme-linked immunosorbent assay was used for measuring collagen type I and III production. RT-PCR and Western blot analysis were used for determining procollagen I and III mRNA expression and protein production. The inhibitors used for pathway determination were: wortmannin [phosphatiylinositol 3-kinase (PI3K)], SB203580 [p38 mitogen-activated protein kinase (MAPK)], PD98059 [extracellular signal-regulated kinase (ERK)1/2)], and JNK inhibitor II [c-Jun NH 2-terminal kinase (JNK)]. We demonstrated that visfatin significantly increased DNA and collagen synthesis in a dose- and time-dependent manner. Cell cycle analysis showed that visfatin increased S-stage percentage and proliferation index in a dose- and time-dependent manner. It was also found that visfatin upregulated collagen I and III production, procollagen I and III mRNA expression and protein production. These effects were diminished by SB203580, wortmannin, and PD98059, but not by JNK inhibitor II. These results suggest that visfatin promote CFs proliferation and collagen synthesis via p38MAPK, PI3K, and ERK 1/2 pathways rather than JNK pathways, which also indicate that visfatin might play a role in myocardial fibrosis.

Effect of triterpene acids of Eriobotrya japonica (Thunb.) Lindl. leaf and MAPK signal transduction pathway on inducible nitric oxide synthase expression in alveolar macrophage of chronic bronchitis rats

The goal of this study was to investigate the possible therapy mechanism of triterpene acids of Eriobotrya japonica (Thunb.) Lindl. Leaf (TAL) in alveolar macrophage (AM) of chronic bronchitis (CB) rats. CB model was established by injection of bacillus calmette guein (BCG) plus lipopolisacharide (LPS) in rats. TAL significantly inhibited the increased NO concentration, iNOS expression and phosphorylation of p38 MAPK in alveolar macrophages (AMs) of CB rats. Using in vivo test, we found that SB203580, a p38 MAPK inhibitor, (10 muM) significantly inhibited inducible nitric oxide synthase (iNOS) mRNA expression in AM. This data indicate that TAL highly decreases excessive iNOS expression and NO induction, and p38 MAPK signal transduction participates in iNOS expression and NO induction in AM of CB rats. The effect of TAL on iNOS expression in AM may be related to its inhibition of p38 MAPK signal transduction.

Identification of the dual specificity and the functional domains of the cardiac-specific protein kinase TNNI3K

Molecular cloning of cardiac troponin I-interacting kinase (TNNI3K), a novel cardiac-specific protein kinase containing seven N-terminal ankyrin (ANK) repeats followed by a protein kinase domain and a C-terminal Ser-rich domain, has previously been reported. In the present study, we show that the C-terminal functional region of TNNI3K negatively regulates the kinase activity, and the N-terminal ANK domain is necessary for autophosphorylation. An in vitro kinase assay shows that TNNI3K exhibits dual-specific kinase activity and forms dimers or oligomers that may be necessary for its activation.

Photoconductive characteristics of single-crystal CdS nanoribbons

The photoconductive characteristics of CdS single nanoribbons were investigated. The device characteristics, including spectral response, light intensity response, and time response, were studied systematically. It is found that CdS nanoribbon has the response speed substantively faster than those ever reported for conventional film and bulk CdS materials and the size of nanoribbons has a significant influence on the response speed with smaller CdS nanoribbons showing higher response speed. The high photosensitivity and high photoresponse speed are attributable to the large surface-to-volume ratio and high single-crystal quality of CdS nanoribbons and the reduction of recombination barrier in nanostructures. Measurements in a different atmosphere demonstrate that the absorption of ambient gas (mainly oxygen) can significantly change the photosensitivity of CdS nanoribbons through trapping electrons from the nanoribbons.

Effects of chronic lead exposure on 1H MRS of hippocampus and frontal lobes in children

The authors performed IQ testing and magnetic resonance spectroscopy on six lead-exposed and six control children. Levels of N-acetyl aspartate (neuronal density and mitochondrial metabolism), creatine + phosphocreatine (phosphate metabolism), and choline (membrane turnover) were decreased in four brain regions (left and right frontal, left and right hippocampus) in lead-exposed children vs controls. The reductions were right frontal > left frontal > hippocampus but were the same bilaterally in the hippocampus.

Clinicopathologic study of 24 cases of cherubism

The authors reviewed 24 cases of familial or nonfamilial cherubism. The age at onset was between 6 and 10 years. It was characterized by bilateral painless swelling of jaws and eyes-to-heaven appearance was visible when the maxillae were affected as well. Radiographs showed well-defined multilocular radiolucencies and with age, thick sclerotic borders were visible. A malocclusive and abnormal dentition, worse in the mandible can be seen. Histopathologically, numerous randomly distributed multinucleated giant cells and vascular spaces within a fibrous connective tissue stroma with or without eosinophilic collagen perivascular cuffing were apparent. Multinucleated giant cells were positive for osteoclastic specific markers, tartrate-resistant acid phosphatase and human alphaV beta3 integrin, 23C6. Results after follow-up were available for 14 cases. Of these, no treatment was carried out in five cases, cherubism resolved (three cases) or grew slowly (two cases); curettage or surgical contouring was performed in seven cases, during the rapid growth of the lesions. This not only gave good immediate results, but also arrested active growth of remnant cherubic lesions and even stimulated bone regeneration. Segmental mandibulectomy followed by reconstruction was performed in two cases with extensive lesion and the risk of pathologic fracture of the mandible, and excellent results were obtained.

Interfacial Study of Cubic Boron Nitride Films Deposited on Diamond

We have studied the nucleation and growth of cubic boron nitride (cBN) films deposited on silicon and diamond-coated silicon substrates using fluorine-assisted chemical vapor deposition (CVD). These comparative studies substantiate that the incubation amorphous/turbostratic BN layers, essential for the cBN nucleation on silicon, are not vital precursors for cBN nucleation on diamond, and they are inherently eliminated. At vastly reduced critical bias voltage, down to -10 V, cBN growth is still maintained on diamond surfaces, and cBN and underlying diamond crystallites exhibit an epitaxial relationship. However, the epitaxial growth is associated with stress in the cBN-diamond interfacial region. In addition, some twinning of crystallites and small-angle grain boundaries are observed between the cBN and diamond crystallites because of the slight lattice mismatch of 1.36%. The small-angle grain boundaries could be eliminated by imposing a little higher bias voltage during the initial growth stage. The heteroepitaxial growth of cBN films on different substrate materials are discussed in the view of lattice matching, surface-energy compatibility, and stability of the substrate against ion irradiation.

Visualization of diamond nucleation and growth from energetic species

The mystery of diamond nucleation by energetic species is resolved via a special deposition scheme. The evolution of the precursor material for diamond nucleation and the development of the nanodiamond crystallites are visualized by high resolution electron microscopy and other spectroscopies. The diamond precipitation and growth are explained in terms of our recently proposed mechanism [Science 297, 1531 (2002)]]: (i) precipitation of sp(3) clusters a small fraction of which are perfect diamond; (ii) growth of diamond crystallites by preferential displacement of amorphous carbon atoms leaving diamond atoms intact. This general scheme is applicable to other materials such as cubic boron nitride.

Effects of lead exposure on long-term potentiation induced by 2-deoxy-D-glucose in area CA1 of rat hippocampus in vitro

Chronic developmental lead exposure is known to be associated with cognitive dysfunction in children. Previous studies have demonstrated that chronic lead exposure could impair the induction and maintenance of long-term potentiation induced by high-frequency stimulation (HFS-LTP). In area CA1 of rat hippocampus, long-term potentiation could also be induced following temporary replacement of 10 mM 2-deoxy-D-glucose (2-DG) for 10 mM glucose in the normal perfusate (artificial cerebrospinal fluid). The present study was carried out to investigate whether chronic lead exposure affected long-term potentiation induced by 2-DG (2-DG-LTP). Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams whose drinking water contained 0.2% lead acetate. Field excitatory postsynaptic potentials (EPSPs) in area CA1 of hippocampus were recorded on postnatal days 25-30. 2-DG application was followed by an increase in EPSP slopes in a time-course-dependent manner in both control and lead-exposed rats, while the amplitude of 2-DG-LTP in the lead-exposed rats (225.9+/-19.0%, n=12) was significantly greater than that in controls (155.2+/-9.8%, n=12). In contrast to the effects of lead exposure on 2-DG-LTP, the amplitude of HFS-LTP in the lead-exposed rats (121.5+/-13.7%, n=12) was significantly less than that in controls (183.9+/-18.6%, n=12). These results indicate that chronic lead exposure had opposite effects on the two types of LTP induced by HFS and 2-DG. This would suggest that the effects of lead on HFS-LTP and 2-DG-LTP are the result of different sites of lead toxicity.

[Killing effect of human pulmonary adenocarcinoma cells with TK + CD/5-Fc + GCV coexpression suicide gene systems]

OBJECTIVE

To investigate the different killing effect to human pulmonary adenocarcinoma cell line cells GLC-82 with coexpressed double suicide genes compared with single gene.

METHODS

Recombinant expression vectors containing CD (cytosine deaminase) and/or TK (thymidine kinase) gene under CMV promoter were constructed successfully. The vectors were transfected to GLC-82 tumor cell lines by use of lipofectamine. The clones were picked out after G418 selection. Extraneous gene integration and expression were confirmed by PCR and semi-quantitative RT-PCR. The cytotoxicity to these transgenic cells under treatment with 5-Fc and GCV were measured by MTT assays.

RESULTS

Double and single suicide gene transfer were both stably expressed in GLC-82 cells. The cytotoxic effects of co-expressed TK-CD genes were superior than that of the single gene.

CONCLUSION

The CD + TK/5-Fc + GCV co-expression system is more effective for killing effect of tumor cells than CD/5-Fc or TK/GCV system alone.

Two components of long-term depression are impaired by chronic lead exposure in area CA1 and dentate gyrus of rat hippocampus in vitro

Previous studies have demonstrated that low-level lead exposure can impair the induction of long-term depression (LTD) in area CA1 and dentate gyrus (DG) of rat hippocampus in vitro and in vivo. The induction of LTD in area CA1 and DG has been shown to associate with N-methyl-D-aspartate receptors (NMDARs) and voltage-gated calcium channel (VGCC). In this study, the relative contributions of NMDARs-dependent and VGCC-dependent components in the induction of LTD in the hippocampus and the impairments of these two components of LTD by chronic low-level lead exposure were investigated. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in area CA1 and DG before and after two 15-min trains of 1-Hz low-frequency stimulation (LFS) (2x900 pulses). In area CA1, the amplitude of NMDARs-dependent LTD (NMDA-LTD), in the presence of 10 microM nimodipine (a blocker of L-type Ca(2+) channels), was 80.05+/-2.54% (n=8) and 94.58+/-10.57% (n=8) in the control and lead-exposed rats, respectively. The amplitude of VGCC-dependent LTD (VGCC-LTD), in the presence of 50 microM (-)-2-amino-5-phosphonopentanoic acid (AP5), was 80.36+/-4.08% (n=10) and 93.91+/-7.85% (n=10) in the control and lead-exposed rats, respectively. In area DG the amplitude of NMDA-LTD, with both 50 microM Ni(2+) (a blocker of T-type Ca(2+) channels) and 10 microM nimodipine present, in the control rats (79. 97+/-4.30%, n=8) was significantly larger than that in the lead-exposed rats (91.24+/-11.08%, n=10, P<0.001). The amplitude of VGCC-LTD, with 50 microM AP5 present, was significantly larger in the control rats (70.80+/-3.64%, n=9) than that in the lead-exposed rats (87.60+/-9.00%, n=10, P<0.001). The results suggested that chronic lead exposure affected two components of LTD induction in area CA1 and DG. Furthermore, the impairment of two components by lead exposure might be similar in area CA1, while the impairment of VGCC-LTD might be more serious in DG of hippocampus.

Image segmentation and bright contrast spot localization of the high resolution atomic image

Some basic quantitative analysis techniques of digitized high resolution atomic image are developed in this paper. We describe how to divide the atomic image into small independent areas with special structure information by the valley mesh segmentation method. The procedure is with regard to the bright contrast spot segmentation of atomic images. We suggest several ways for bright contrast spot localization in images. Calculation routines for peak detection and weighted local position average methods for this purpose are given.

[Applied study on MRI diagnosis of the oral and maxillofacial masses.]

38 cases of Oral and Maxillofacial masses were selected to be studied by MRI,combined with fine neddle aspiration cytologic examination,compared with CT scan.The authors thought that MRI was clear,high resolving power of soft tissue,able to find out the bone infiltration of the Oral Maxillofacial masses and hemangioma or lymphoangioma etc,those which were suspected to invade the crania base,tip of orbit,pterygopalatine fossa,parapharyngeal,the vital blood vessel of the neck,primary study on MRI supervising local recur after the maxillofacial tumors being resected was also done.

Functional compartments in the portal system. An experimental study

The pressure of the portal trunk, the left gastric vein, the left and right gastroepiploic veins, the mesenteric vein and the abdominal aorta was measured experimentally at the same time in 10 normal dogs. The levels of the raised pressure in the different compartments with their outflow tracts obstructed respectively were observed and the potentials of the functional barriers between these compartments were quantitatively evaluated. The findings showed that the average power of the functional barriers was 45.1 +/- 5.7% between the different compartments in the gastrosplenic area and 74.3% in the mesenteric region. The weakness of the functional barriers' capacity limiting the collateral diversion between the lesser and greater splanchnic systems may be one of the causes making the distal splenorenal shunt lose its selectivity.

[Mechanism of damage to erythrocytes after burn injury in rat--changes in lipid peroxidation, antioxidant function and sulfhydryl groups]

Thermal burn on the back of rat (20% TBSA full-thickness burn) was used to study the changes in free radicals and lipid peroxidation and function of the antioxidation of erythrocytes postburn. It was found that there were increase in the concentration of lipid peroxides and decrease in activity of glutathione peroxidase (GSHpx) in plasma. The activity of RBC GSHpx increased significantly on day 1 postburn. When RBC GSHpx could not resist the injury, the function of antioxidation decreased, such as the activities of G6PD, GSHpx and the concentration of GSH and NPSH. RBC LPO increased, which cross-linked with sulfhydryl proteins and inflicted injury to RBC membrane. It might be concluded that the mechanism of damage of RBC after burn injury is due to chain reactions of free radicals and lipid peroxidation of the cell membrane. It also proved that there were changes in functional capability of antioxidation in vivo after burn injury. Further study is needed to locate the site of production of free radicals within or/and in the neighborhood of RBC and elucidate the transfer of the messages which cause the change.

Studies on the ultrastructure of envelope of elementary bodies of Chlamydia trachomatis

Electron microscopy of purified Chlamydia trachomatis treated by various physical and chemical means shows that the envelope of the elementary bodies (EB) consists of the outer cell wall layer, the inner cell wall layer, and the inner membrane. The outer cell wall layer is mainly made up of granular subunits arranged in a hexagonal pattern and may be called the "mural structural protein layer". It forms together with the inner cell wall layer the rigid cell wall. The inner or protoplasmic membrane is not easily shown in the young EB. In the negatively stained specimen, a frail and easily removable superficial layer is seen adhering to the "mural structural protein layer". But in ultra-thin sections this superficial layer is not shown separately. There are fold-like grooves which are special structures probably related to reproduction. There are seen some EB's in binary fission, and a number of bodies very big in size yet having morphological characteristics of the EB's, which are in various processes of multiplication, such as binary fission, budding, and "multicentered germination". These observations give a challenge to the current opinion that only the initial bodies have the power of reproduction.