Brassinosteroid and Hydrogen Peroxide Interdependently Induce Stomatal Opening by Promoting Guard Cell Starch Degradation.

Starch is the major storage carbohydrate in plants and functions in buffering carbon and energy availability for plant fitness with challenging environmental conditions. The timing and extent of starch degradation appear to be determined by diverse hormonal and environmental signals; however, our understanding of the regulation of starch metabolism is fragmentary. Here, we demonstrate that the phytohormone brassinosteroid (BR) and redox signal hydrogen peroxide (H2O2) induce the breakdown of starch in guard cells, which promotes stomatal opening. The BR-insensitive mutant bri1-116 accumulated high levels of starch in guard cells, impairing stomatal opening in response to light. The gain-of-function mutant bzr1-1D suppressed the starch excess phenotype of bri1-116, thereby promoting stomatal opening. BRASSINAZOLE-RESISTANT1 (BZR1) interacts with the basic leucine zipper transcription factor G-BOX BINDING FACTOR2 (GBF2) to promote the expression of ß-AMYLASE1 (BAM1), which is responsible for starch degradation in guard cells. H2O2 induces BZR1 oxidation, enhancing the interaction between BZR1 and GBF2 to increase BAM1 transcription. Mutations in BAM1 lead to starch accumulation and reduce the effects of BR and H2O2 on stomatal opening. Overall, this study uncovers the critical roles of BR and H2O2 in regulating guard cell starch metabolism and stomatal opening.

Interferon-α-induced CD100 on naïve CD8+ T cells enhances antiviral responses to hepatitis C infection through CD72 signal transduction.

Objectives We investigated the effects of CD100 on naïve CD8+ T cells during hepatitis C virus (HCV) infection after interferon-α (IFN-α) therapy to clarify the mechanism underlying the effect of IFN-α in enhancing the antiviral response. Methods The CD100 molecules on subsets of CD8+ T cells were analysed with flow cytometry. The effects of CD100-overexpressing naïve CD8+ T cells were determined with ELISAs and an MTT cytotoxicity assay. The role of CD100-CD72 signal transduction was analysed with a neutralization and transwell assays. Results HCV infection reduced CD100 expression on CD8+ T cells, whereas IFN-α treatment significantly increased CD100 expression on naïve CD8+ T cells. The increased CD100 interacted with the CD72 receptor and enhanced PBMC cytokine secretion (IFN-γ and tumour necrosis factor-α) and cytotoxicity. Conclusions IFN-α-induced CD100 on naïve CD8+ T cells promotes PBMC cytokine secretion and cytotoxicity through CD100-CD72 signalling during HCV infection.

Metastatic lung adenocarcinoma to the bladder: A case report.

Urothelial cancer is the most frequently diagnosed type of malignant tumor in the bladder, of which primary adenocarcinoma accounts for a small percentage. Secondary malignancies, in particular metastatic adenocarcinoma from the lung, are exceedingly rare, with only six cases previously reported in the literature. The present study describes the case of a 71-year-old Chinese male patient with known lung cancer for >2 years, who was diagnosed with metastatic adenocarcinoma to the bladder. The histopathological characteristics and immunohistochemical features of the patient are reported. It was proposed that pathologists should consider the possibility of metastatic adenocarcinoma from the lung, rather than assume a diagnosis of primary adenocarcinoma of the bladder or direct invasion of adenocarcinoma from the surrounding organs. Furthermore, it is essential to determine the medical history of each patient and observe the immunohistochemical features of all tumors prior to diagnosis.

Diagnostic accuracy of intracellular mycobacterium tuberculosis detection for tuberculous meningitis.

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.

HIF-1α up-regulates NDRG1 expression through binding to NDRG1 promoter, leading to proliferation of lung cancer A549 cells.

Hypoxia-inducible signaling pathway is involved in many pathological processes, such as adaptiveness regulation of plateau environment, myocardial ischemia and tumorigenesis. NDRG1 is a member of the N-myc downregulated gene (NDRG) family, and it has strong hypoxia stress reaction functions. Although the cellular responses to hypoxia are well known, little is known about the interaction between hypoxia-inducible transcription factor (HIF)-1α and NDRG1. In this study, we cloned HIF-1α CDS, NDRG1 promoter and its truncatures, constructed pCDNA3.0-Hif-1α and pGL3-basic-NDRG1. Reporter assay results showed that HIF-1α could bind to NDRG1 promoter to activate NDRG1 expression. Further results revealed that -1202 to -450 of NDRG1 promoter is the most important region for HIF-1α binding. Then, we constructed NDRG1 stable transfection cell line. Results from MTT, colony-forming assay and flow cytometry showed that NDRG1 overexpression results in more proliferation and less apoptosis of A549 lung cancer cells. Our study elucidates the mechanism of NGRG1 in hypoxia stress reactions and may provide new strategy for hypoxia injuries.

A highly efficient Ziehl-Neelsen stain: identifying de novo intracellular Mycobacterium tuberculosis and improving detection of extracellular M. tuberculosis in cerebrospinal fluid.

Tuberculous meningitis leads to a devastating outcome, and early diagnosis and rapid chemotherapy are vital to reduce morbidity and mortality. Since Mycobacterium tuberculosis is a kind of cytozoic pathogen and its numbers are very few in cerebrospinal fluid, detecting M. tuberculosis in cerebrospinal fluid from tuberculous meningitis patients is still a challenge for clinicians. Ziehl-Neelsen stain, the current feasible microbiological method for the diagnosis of tuberculosis, often needs a large amount of cerebrospinal fluid specimen but shows a low detection rate of M. tuberculosis. Here, we developed a modified Ziehl-Neelsen stain, involving cytospin slides with Triton processing, in which only 0.5 ml of cerebrospinal fluid specimens was required. This method not only improved the detection rate of extracellular M. tuberculosis significantly but also identified intracellular M. tuberculosis in the neutrophils, monocytes, and lymphocytes clearly. Thus, our modified method is more effective and sensitive than the conventional Ziehl-Neelsen stain, providing clinicians a convenient yet powerful tool for rapidly diagnosing tuberculous meningitis.

Cytotoxic T-lymphocyte antigen 4 gene +49A/G polymorphism significantly associated with susceptibility to primary biliary cirrhosis: a meta-analysis.

OBJECTIVE: To evaluate comprehensively the association of cytotoxic T-lymphocyte antigen 4 (CTLA-4) +49A/G polymorphism with susceptibility to primary biliary cirrhosis (PBC). METHODS: PubMed was used to search for the relevant published articles. The risk of PBC association with the CTLA-4+49A/G polymorphism was estimated for each study in a random-effects model. Odds ratio (OR) and 95% confidence interval (CI) were estimated for each study. Risks to PBC were estimated by stratified analysis in patients with different ethnicity and antimitochondrial antibody (AMA) status, as well as histological stages. RESULTS: A total of 12 articles were included in the study. An association between PBC and CTLA-4 G allele was found, overall OR = 1.20, 95% CI 1.03-1.41 (P = 0.02). However, stratification by ethnicity indicated a significant association between the G allele and PBC in Asians (OR = 1.36, 95% CI 1.12-1.65, P = 0.002), but not in Caucasians (OR = 1.15, 95% CI 0.95-1.39, P = 0.15). Moreover, AMA positive patients carrying G allele were more susceptible to PBC compared with AMA negative patients (OR = 1.23, 95% CI 1.06-1.43, P = 0.007; OR = 0.98, 95% CI 0.71-1.34, P = 0.88, respectively). CONCLUSIONS: Polymorphism in exon 1 of CTLA-4 gene at position 49 may act as a candidate of susceptibility locus to PBC. However, larger studies with participants of varying ethnicity and stratified by clinical and laboratory characteristics are needed to validate our findings.

[The construction and primary screening of a phage display library of HCV C and E1 genes evolved with an artificial pattern].

OBJECTIVES: To construct and screen a primarily phage display library of HCV C and E1 genes evolved with an artificial pattern. METHODS: Two genes of about 1 kb with different genotypes were evolved by DNA shuffling. The re-assembled HCV C and E1 genes were cloned into a phage vector. After being rescued with helper phage M13KO7, a phage display library was constructed. Then the library was screened with anti-C and E1 McAb. Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) was carried out on twenty individual phage clones selected randomly to detect their binding and reactive activity with high-titer HCV-positive sera. Normal sera were used as controls. RESULTS: The phage display library of HCV C and E1 genes which evolved with an artificial pattern was constructed. Their capacity amounted to 1.64 x 10(6), and 86 percent of the clones contained C and E1 genes. After four rounds of panning, the phage library was specifically enriched. Twelve positive clones were successfully screened. CONCLUSION: The capacity and diversity of the constructed library are enough for screening. The results demonstrate the superiority of the specific binding and reactive activity and affinity of the 12 phage clones from the HCV positive sera.

[Experimental study on the effect of VEGF165 antisense RNA on human squamous cell carcinoma of esophagus].

AIM: To investigate the effect of antisense RNA against vascular endothelial growth factor 165 (VEGF165) on human esophagus squamous cell carcinoma cell line EC109. METHODS: Eukaryotic expression vector for VEGF165 antisense RNA was constructed and identified. Recombinant plasmid was transfected into EC109 cells and the transfected EC109 cells were inoculated subcutaneously to nude mice. The biological characteristics and tumorigenicity of transfected EC109 cells were observed by in situ hybridization, laser confocal microscope, transmission electron microscopy and flow cytometry. RESULTS: The eukaryotic expression vector pCEP-AVEGF165 was successfully constructed and expressed in transfected EC109 cells. The rate of VEGF165 expression dropped by 75% in transfected cells. The morphology and cell cycle of transfected EC109 cells were not affected by the antisense RNA, but the tumorigenicity and angiogenesis of transfected EC109 cells were greatly reduced in nude mice. The volume of tumors in pCEP-AVEGF165 transfected group, empty vector transfected group and control group were (820+/-112.5) mm3, (7 930+/-1 035) mm3 and (7 850+/-950) mm3, respectively. The microvessel density of the three groups were (8.5+/-1.2)/mm2, (44.3+/-9.4)/mm2 and (46.4+/-12.6)/mm2, respectively. CONCLUSION: The angiogenesis and tumorigenicity of human esophageal squamous cell carcinoma were effectively inhibited by VEGF165 antisense RNA, which may be applied to treat solid tumor in the future.

Synthesis of ribozyme against vascular endothelial growth factor165 and its biological activity in vitro.

AIM: To investigate the designation, synthesis and biological activity of against vascular endothelial growth factor165 (VEGF165) ribozyme. METHODS: The ribozyme against VEGF165 was designed with computer. The transcriptional vector was constructed which included the anti-VEGF165 ribozyme and 5', 3' self-splicing ribozymes. The hammerhead ribozyme and substrate VEGF165 mRNA were synthesized through transcription in vitro. The cleavage activity of the ribozyme on target RNA was observed in a cell-free system. RESULTS: The anti-VEGF165 ribozyme was released properly from the transcription of pGEMRz212 cleaved by 5' and 3' self-splicing ribozymes which retained its catalytic activity, and the cleavage efficiency of ribozyme reached 90.7%. CONCLUSION: The anti-VEGF165 ribozyme designed with computer can cleave VEGF165 mRNA effectively.

[Construction, identification and expression of three kinds of shuttle plasmids of adenovirus expression vector of hepatitis C virus structure gene].

OBJECTIVE: To construct three recombinant shuttle plasmids of adenovirus expression vector which can express hepatitis C virus(HCV) different structure genes(C, C+E1, C+E1+E2) in order to pack adenovirus expression vectors which can express HCV different structure gene effectively. METHODS: The different HCV structure genes derived from the plasmid pBRTM/HCV1-3011 by using polymerase chain reaction (PCR) were inserted into the backward position of cytomegalovirus(CMV) immediate early promotor element of shuttle plasmid(pAd.CMV-Link.1) of adenovirus expression vector respectively, then the three recombinant plasmids (pAd.HCV-C, pAd.HCV-CE1, pAd.HCV-S) were obtained. The recombinant plasmids were identified by endonuclease, PCR and sequencing. HCV structure genes were expressed transiently with Lipofectamine 2000 coated in HepG2 cells which were confirmed by immunofluorescence and Western-Blot. RESULTS: Insert DNAs of the three recombinant plasmids' were confirmed to be HCV different structure genes by endonuclease, PCR and sequencing. The three recombinant plasmids can express HCV structure gene (C, C+E1, C+E1+E2) transiently in HepG2 cells which were confirmed by immunofluorescence and Western-Blot. CONCLUSION: The three recombinant shuttle plasmids of adenovirus expression vector can express HCV structure gene(C, C+E1, C+E1+E2) transiently. This should be useful to pack adenovirus expression vector which can express HCV structure genes.

[Inhibition of momordica anti-HIV protein of MAP30 on HBeAg expression by laser scanning confocal microscopy].

AIM: To investigate the effect of momordica anti-HIV protein of M(r ) being 30 000 (MAP30) on HBV expression by laser scanning confocal microscopy. METHODS: HBV DNA-transfected hepatocarcinoma cells 2.2.15 were cultured in the presence of MAP30. Then quantitative analysis of HBeAg expression in the 2.2.15 cells by laser scanning confocal microscopy after indirect immunofluorescence staining was performed. RESULTS: The fluorescence intensity in 2.2.15 cells co-cultured with MAP30 was notably weaker than that in control cells. CONCLUSION: MAP30 can effectively inhibit HBeAg expression in the 2.2.15 cells.

VEGF165 antisense RNA suppresses oncogenic properties of human esophageal squamous cell carcinoma.

AIM: To investigate the effect of antisense RNA to vascular endothelial growth factor165 (VEGF165) on human esophageal squamous cell carcinoma cell line EC109 and the feasibility of gene therapy for esophageal carcinoma. METHODS: By using subclone technique, the full length of VEGF165 amino acid cDNA, which was cut from pGEM-3Zf+,was cloned inversely into the eukaryotic expression vector pCEP4. The recombinant plasmid pCEP-AVEGF165 was transfected into EC109 cell with lipofectamine. After a stable transfection, dot blot, enzyme-linked immunosorbent assay (ELISA),laser confocal imaging system analysis, transmission electron microscopy and flow cytometry were performed to determine the biological characteristics of EC109 cell line before and after transfection in vitro and whether there was a reversion in the tumorigenic properties of the EC109 cell in vitro. RESULTS: The eukaryotic expression vector pCEP-AVEGF165 was successfully constructed and transfected into EC109 cells. The expression of VEGF165 was significantly decreased in the transfected cells while the biological characteristics of the cells were not influenced by the expression of antisense gene. The tumorigenic and angiogenic capabilities were greatly reduced in nude mice, as demonstrated by reduced tumor end volume (820+/-112.5)mm(3) vs (7930+/-1035)mm(3) and (7850+/-950)mm(3), P<0.01) and microvessel density (average number: (8.5+/-1.2)mm(-2) vs (44.3+/-9.4)mm(-2) and (46.4+/-12.6)mm(-2), P<0.01) in comparison between experimental groups empty vector transfected group and control group. CONCLUSION: The angiogenesis and tumorigenicity of human esophageal squamous cell carcinoma were effectively inhibited by VEGF165 antisense RNA. Antisense RNA to VEGF165 can potentially be used as an adjuvant therapy for solid tumors.