Demethoxycurcumin Retards Cell Growth and Induces Apoptosis in Human Brain Malignant Glioma GBM 8401 Cells

Demethoxycurcumin (DMC; a curcumin-related demethoxy compound) has been recently shown to display antioxidant and antitumor activities. It has also produced a potent chemopreventive action against cancer. In the present study, the antiproliferation (using the MTT assay, DMC was found to have cytotoxic activities against GBM 8401 cell with IC50 values at 22.71 μM) and induced apoptosis effects of DMC have been investigated in human brain malignant glioma GBM 8401 cells. We have studied the mitochondrial membrane potential (MMP), DNA fragmentation, caspase activation, and NF-κB transcriptional factor activity. By these approaches, our results indicated that DMC has produced an inhibition of cell proliferation as well as the activation of apoptosis in GBM 8401 cells. Both effects were observed to increase in proportion with the dosage of DMC treatment, and the apoptosis was induced by DMC in human brain malignant glioma GBM 8401 cells via mitochondria- and caspase-dependent pathways

Maintaining the structural integrity of thebamboo mosaic virus 3′ untranslated region isnecessary for retaining the catalytic constant forminus-strand RNA synthesis

Background: Bamboo mosaic virus (BaMV) and the Potato virus X (PVX) are members of the genus Potexvirus andhave a single-stranded positive-sense RNA genome. The 3′-untranslated region (UTR) of the BaMV RNA genomewas mapped structurally into ABC (a cloverleaf-like), D (a stem-loop), and E (pseudoknot) domains. The BaMVreplicase complex that was isolated from the infected plants was able to recognize the 3′ UTR of PVX RNA toinitiate minus-strand RNA synthesis in vitro.Results: To investigate whether the 3′ UTR of PVX RNA is also compatible with BaMV replicase in vivo, weconstructed chimera mutants using a BaMV backbone containing the PVX 3′ UTR, which was inserted in or used toreplace the various domains in the 3′ UTR of BaMV. None of the mutants, except for the mutant with the PVX3′ UTR inserted upstream of the BaMV 3′ UTR, exhibited a detectable accumulation of viral RNA in Nicotianabenthamiana plants. The in vitro BaMV RdRp replication assay demonstrated that the RNA products were generatedby the short RNA transcripts, which were derived from the chimera mutants to various extents. Furthermore, theVmax/KM of the BaMV 3′ UTR (rABCDE) was approximately three fold higher than rABCP, rP, and rDE in minus-strandRNA synthesis. These mutants failed to accumulate viral products in protoplasts and plants, but were adequatelyreplicated in vitro.Conclusions: Among the various studied BaMV/PVX chimera mutants, the BaMV-S/PABCDE that containednon-interrupted BaMV 3′ UTR was the only mutant that exhibited a wild-type level of viral product accumulation inprotoplasts and plants. These results indicate that the continuity of the domains in the 3′ UTR of BaMV RNA wasnot interrupted and the domains were not replaced with the 3′ UTR of PVX RNA in vivo

“I can’t see an end in sight.” How the COVID-19 pandemic may influence suicide risk: a qualitative study

<jats:p> Zusammenfassung: Theoretischer Hintergrund: Das Ziel der vorliegenden Studie war es, eine deutschsprachige Adaptation der Bergen Study Addiction Scale (BStAS), einer Skala zur Erfassung von exzessivem Studierverhalten, zu entwickeln und zu validieren. Methode: Die Daten von 615 Studierenden wurden analysiert. Die Dimensionalität der BStAS wurde mittels konfirmatorischer Faktorenanalyse überprüft. Außerdem wurden Korrelations- und hierarchische Regressionsanalysen durchgeführt, um Zusammenhänge von exzessivem Studierverhalten mit Persönlichkeit und Gesundheit zu untersuchen. Ergebnisse: Der Vergleich mit Dynamic Fit Index Cutoffs deutete auf eine moderate Missspezifikation des einfaktoriellen Modells hin. Wie erwartet war exzessives Studierverhalten positiv mit wöchentlichen Lernstunden, Neurotizismus, wahrgenommenem Stress, psychosomatischen Beschwerden und Schlafproblemen assoziiert und hing negativ mit Lebenszufriedenheit zusammen. Schlussfolgerung: Es ist fraglich, ob alle Items der BStAS Aspekte einer Verhaltenssucht erfassen. Die Ergebnisse legen dennoch nahe, dass die BStAS ein Studierverhalten misst, das in Bezug auf physische und psychische Gesundheit von Relevanz ist. </jats:p&gt

Elevated plasma level of visfatin/pre-b cell colony-enhancing factor in male oral squamous cell carcinoma patients

Objectives: Visfatin, also known as nicotiamide phosphoribosyltransferase or pre-B cell colony enhancing factor, is a pro-inflammatory cytokine whose serum level is increased in various cancers. In this study, we investigated whether plasma visfatin levels were altered in patients with oral squamous cell carcinoma (OSCC). The relation ship between plasma visfatin levels and the pretreatment hematologic profile was also explored. Study Design: Plasma visfatin concentrations were measured through ELISA in OSCC patients and control sub- D esign: Plasma visfatin concentrations were measured through ELISA in OSCC patients and control sub- esign: Plasma visfatin concentrations were measured through ELISA in OSCC patients and control sub jects. A total of 51 patients with OSCC and 57 age- and body mass index (BMI)-matched control subjects were studied. All study subjects were male. Results: Plasma visfatin was found to be elevated in patients with OSCC (7.0 ± 4.5 vs. 4.8 ± 1.9 ng/ml, p = 0.002). Multiple logistic regression analysis revealed visfatin as an independent association factor for OSCC, even after full adjustment of known biomarkers. Visfatin level was significantly correlated with white blood cell (WBC) count, neutrophil count, and hematocrit (all p < 0.05). In addition, WBC count, neutrophil count, and visfatin gradually increased with stage progression, and hematocrit gradually decreased with stage progression (all p < 0.05). Conclusion: Increased plasma visfatin levels were associated with OSCC, independent of risk factors, and were cor related with inflammatory biomarkers. These data suggest that visfatin may act through inflammatory reactions to play an important role in the pathogenesis of OSC

Network Biology of Tumor Stem-like Cells Identified a Regulatory Role of CBX5 in Lung Cancer

Mounting evidence links cancers possessing stem-like properties with worse prognosis. Network biology with signal processing mechanics was explored here using expression profiles of a panel of tumor stem-like cells (TSLCs). The profiles were compared to their parental tumor cells (PTCs) and the human embryonic stem cells (hESCs), for the identification of gene chromobox homolog 5, CBX5, as a potential target for lung cancer. CBX5 was found to regulate the stem-like properties of lung TSLCs and was predictive of lung cancer prognosis. The investigation was facilitated by finding target genes based on modeling epistatic signaling mechanics via a predictive and scalable network-based survival model. Topologically-weighted measurements of CBX5 were synchronized with those of BIRC5, DNMT1, E2F1, ESR1, MLH1, MSH2, RB1, SMAD1 and TAF5. We validated our findings in another Taiwanese lung cancer cohort, as well as in knockdown experiments using sh-CBX5 RNAi both in vitro and in vivo.National Science Council (China) (NSC grant 100-2325-B-010-010-MY3/98-2314-B-010-024-MY2/97-3111-B075-001-MY3/ 96-2314-075-056-MY3)National Yang-Ming University (Ministry of Education, Aim for the Top University Plan: 96ADD122, 96ADD125, 96ADT191, 97ACD113, 97ACT302, 98ACT302, 98ACD107, 98ACT192 and Brain Research Center-3T-MRI project)))Taipei Veterans General Hospital (98-C1-099/E1-003/ER3-001)Taipei Veterans General Hospital (Joint Projects of VGHUST (98-G6-6/ 98-P1-01/99-P6-39)Chi Mei Medical Center (CMYM9801)Yen-Tjing-Ling Medical Foundation (96/97/98)Taipei City Hospital (96-002-62-092)Technology Development Program for Academia (TDPA; 98-EC-17-A-19-S2-0107)Taiwan. Department of Industrial Technology, Ministry of Economic AffairsNational Science Council (China) (NSC 101-2325-B-010 -009)Taiwan. Department of Health. Cancer Research Center of Excellence (DOH101-TD-C-111-007

N-Glycosylation of Human R-Spondin 1 Is Required for Efficient Secretion and Stability but Not for Its Heparin Binding Ability

[[abstract]]R-spondin 1 (Rspo1) plays an essential role in stem cell biology by potentiating Wnt signaling activity. Despite the fact that Rspo1 holds therapeutic potential for a number of diseases, its biogenesis is not fully elucidated. All Rspo proteins feature two amino-terminal furin-like repeats, which are responsible for Wnt signal potentiation, and a thrombospondin type 1 (TSR1) domain that can provide affinity towards heparan sulfate proteoglycans. Using chemical inhibitors, deglycosylase and site-directed mutagenesis, we found that human Rspo1 and Rspo3 are both N-glycosylated at N137, a site near the C-terminus of the furin repeat 2 domain, and Rspo2 is N-glycosylated at N160, a position near the N-terminus of TSR1 domain. Elimination of N-glycosylation at these sites affects their accumulation in media but have no effect on the ability towards heparin. Introduction of the N-glycosylation site to Rspo2 mutant at the position homologous to N137 in Rspo1 restored full glycosylation and rescued the accumulation defect of nonglycosylated Rspo2 mutant in media. Similar effect can be observed in the N137 Rspo1 or Rspo3 mutant engineered with Rspo2 N-glycosylation site. The results highlight the importance of N-glycosylation at these two positions in efficient folding and secretion of Rspo family. Finally, we further showed that human Rspo1 is subjected to endoplasmic reticulum (ER) quality control in N-glycan-dependent manner. While N-glycan of Rspo1 plays a role in its intracellular stability, it had little effect on secreted Rspo1. Our findings provide evidence for the critical role of N-glycosylation in the biogenesis of Rspo1.[[notice]]補正完

Chloroplast phosphoglycerate kinase, a gluconeogenetic enzyme, is required for efficient accumulation of Bamboo mosaic virus

The tertiary structure in the 3′-untranslated region (3′-UTR) of Bamboo mosaic virus (BaMV) RNA is known to be involved in minus-strand RNA synthesis. Proteins found in the RNA-dependent RNA polymerase (RdRp) fraction of BaMV-infected leaves interact with the radio labeled 3′-UTR probe in electrophoretic mobility shift assays (EMSA). Results derived from the ultraviolet (UV) cross-linking competition assays suggested that two cellular factors, p43 and p51, interact specifically with the 3′-UTR of BaMV RNA. p43 and p51 associate with the poly(A) tail and the pseudoknot of the BaMV 3′-UTR, respectively. p51-containing extracts specifically down-regulated minus-strand RNA synthesis when added to in vitro RdRp assays. LC/MS/MS sequencing indicates that p43 is a chloroplast phosphoglycerate kinase (PGK). When the chloroplast PKG levels were knocked down in plants, using virus-induced gene silencing system, the accumulation level of BaMV coat protein was also reduced

Global Analyses of Small Interfering RNAs Derived from Bamboo mosaic virus and Its Associated Satellite RNAs in Different Plants

Background: Satellite RNAs (satRNAs), virus parasites, are exclusively associated with plant virus infection and have attracted much interest over the last 3 decades. Upon virus infection, virus-specific small interfering RNAs (vsiRNAs) are produced by dicer-like (DCL) endoribonucleases for anti-viral defense. The composition of vsiRNAs has been studied extensively; however, studies of satRNA-derived siRNAs (satsiRNAs) or siRNA profiles after satRNA co-infection are limited. Here, we report on the small RNA profiles associated with infection with Bamboo mosaic virus (BaMV) and its two satellite RNAs (satBaMVs) in Nicotiana benthamiana and Arabidopsis thaliana. Methodology/Principal Findings: Leaves of N. benthamiana or A. thaliana inoculated with water, BaMV alone or coinoculated with interfering or noninterfering satBaMV were collected for RNA extraction, then large-scale Solexa sequencing. Up to about 20% of total siRNAs as BaMV-specific siRNAs were accumulated in highly susceptible N. benthamiana leaves inoculated with BaMV alone or co-inoculated with noninterfering satBaMV; however, only about 0.1% of vsiRNAs were produced in plants co-infected with interfering satBaMV. The abundant region of siRNA distribution along BaMV and satBaMV genomes differed by host but not by co-infection with satBaMV. Most of the BaMV and satBaMV siRNAs were 21 or 22 nt, of both (+) and (-) polarities; however, a higher proportion of 22-nt BaMV and satBaMV siRNAs were generated in N. benthamiana than in A. thaliana. Furthermore, the proportion of non-viral 24-nt siRNAs was greatly increased in N. benthamiana after virus infection. Conclusions/Significance: The overall composition of vsiRNAs and satsiRNAs in the infected plants reflect the combined action of virus, satRNA and different DCLs in host plants. Our findings suggest that the structure and/or sequence demands of various DCLs in different hosts may result in differential susceptibility to the same virus. DCL2 producing 24-nt siRNAs under biotic stresses may play a vital role in the antiviral mechanism in N. benthamiana

Hsp90 Interacts Specifically with Viral RNA and Differentially Regulates Replication Initiation of Bamboo mosaic virus and Associated Satellite RNA

Host factors play crucial roles in the replication of plus-strand RNA viruses. In this report, a heat shock protein 90 homologue of Nicotiana benthamiana, NbHsp90, was identified in association with partially purified replicase complexes from BaMV-infected tissue, and shown to specifically interact with the 3′ untranslated region (3′ UTR) of BaMV genomic RNA, but not with the 3′ UTR of BaMV-associated satellite RNA (satBaMV RNA) or that of genomic RNA of other viruses, such as Potato virus X (PVX) or Cucumber mosaic virus (CMV). Mutational analyses revealed that the interaction occurs between the middle domain of NbHsp90 and domain E of the BaMV 3′ UTR. The knockdown or inhibition of NbHsp90 suppressed BaMV infectivity, but not that of satBaMV RNA, PVX, or CMV in N. benthamiana. Time-course analysis further revealed that the inhibitory effect of 17-AAG is significant only during the immediate early stages of BaMV replication. Moreover, yeast two-hybrid and GST pull-down assays demonstrated the existence of an interaction between NbHsp90 and the BaMV RNA-dependent RNA polymerase. These results reveal a novel role for NbHsp90 in the selective enhancement of BaMV replication, most likely through direct interaction with the 3′ UTR of BaMV RNA during the initiation of BaMV RNA replication