24 research outputs found
Regiospecific synthesis of mono-N-substituted indolopyrrolocarbazoles
Two complementary and efficient strategies have been developed for the regiospecific synthesis of unsymmetrical indolopyrrolocarbazoles (IPCs) mono-N-substituted with a pentacycle. A halogen in position 2 of the intermediate bisindolylmaleimides 3a 12e allows a selective Mitsunobu coupling by exploiting the increased acidity of the 2-chloro-substituted indole nitrogen. It also promotes an easier cyclization of bisindolylmaleimides 4a 12e and 7b 12e to IPCs. Alkylation of the 2-unsubstituted indole-3-carboxamides 2a,b and further processing to the corresponding IPCs gives access to the opposite regioisomers
Preparation of N-carbacycle monosubstituted indolocarbazoles for therapeutic use as protein kinase inhibitors
N-(carbacyclyl)-indolocarbazoles, such as I [R = substituted or unsubstituted 5 or 6 membered carbacyclyl; R3, R4 = H, halogen, alkyl, carboxy, carboxamide, amino, alkoxy, etc.], were prepd. as protein kinase inhibitors which are useful for the treatment of non-insulin dependent diabetes mellitus, acute stroke and other neurotraumatic injuries, malignant diseases, and neurodegenerative diseases, such as Alzheimer's disease. Thus, NAD 006 (II) was prepd. via a multistep synthetic sequence starting from cyclopentadiene, 1H-indole-3-acetonitrile and 2-indolone. The prepd. staurosporine analogs were assayed for inhibition of extracellular signal regulated kinase 2, protein kinase A, protein kinase C and glycogen synthase kinase 3\u3b2
Nutritional status, dental caries and tooth eruption in children: a longitudinal study in Cambodia, Indonesia and Lao PDR
Spread of a Distinct Stx2-Encoding Phage Prototype among Escherichia coli O104:H4 Strains from Outbreaks in Germany, Norway, and Georgia
Shiga toxin 2 (Stx2)-producing Escherichia coli (STEC) O104:H4 caused one of the world's largest outbreaks of hemorrhagic colitis and hemolytic uremic syndrome in Germany in 2011. These strains have evolved from enteroaggregative E. coli (EAEC) by the acquisition of the Stx2 genes and have been designated enteroaggregative hemorrhagic E. coli. Nucleotide sequencing has shown that the Stx2 gene is carried by prophages integrated into the chromosome of STEC O104:H4. We studied the properties of Stx2-encoding bacteriophages which are responsible for the emergence of this new type of E. coli pathogen. For this, we analyzed Stx bacteriophages from STEC O104:H4 strains from Germany (in 2001 and 2011), Norway (2006), and the Republic of Georgia (2009). Viable Stx2-encoding bacteriophages could be isolated from all STEC strains except for the Norwegian strain. The Stx2 phages formed lysogens on E. coli K-12 by integration into the wrbA locus, resulting in Stx2 production. The nucleotide sequence of the Stx2 phage P13374 of a German STEC O104:H4 outbreak was determined. From the bioinformatic analyses of the prophage sequence of 60,894 bp, 79 open reading frames were inferred. Interestingly, the Stx2 phages from the German 2001 and 2011 outbreak strains were found to be identical and closely related to the Stx2 phages from the Georgian 2009 isolates. Major proteins of the virion particles were analyzed by mass spectrometry. Stx2 production in STEC O104:H4 strains was inducible by mitomycin C and was compared to Stx2 production of E. coli K-12 lysogens
Development of inhibitors of pathological tau hyperphosphorylation for a disease modifying approach to Alzheimer's disease
Topical silver diamine fluoride for dental caries arrest in preschool children: A randomized controlled trial and microbiological analysis of caries associated microbes and resistance gene expression
ObjectivesThe Stopping Cavities Trial investigated effectiveness and safety of 38% silver diamine fluoride in arresting caries lesions.Materials and methodsThe study was a double-blind randomized placebo-controlled superiority trial with 2 parallel groups. The sites were Oregon preschools. Sixty-six preschool children with ≥1 lesion were enrolled. Silver diamine fluoride (38%) or placebo (blue-tinted water), applied topically to the lesion. The primary endpoint was caries arrest (lesion inactivity, Nyvad criteria) 14-21days post intervention. Dental plaque was collected from all children, and microbial composition was assessed by RNA sequencing from 2 lesions and 1 unaffected surface before treatment and at follow-up for 3 children from each group.Results and conclusionAverage proportion of arrested caries lesions in the silver diamine fluoride group was higher (0.72; 95% CI; 0.55, 0.84) than in the placebo group (0.05; 95% CI; 0.00, 0.16). Confirmatory analysis using generalized estimating equation log-linear regression, based on the number of arrested lesions and accounting for the number of treated surfaces and length of follow-up, indicates the risk of arrested caries was significantly higher in the treatment group (relative risk, 17.3; 95% CI: 4.3 to 69.4). No harms were observed. RNA sequencing analysis identified no consistent changes in relative abundance of caries-associated microbes, nor emergence of antibiotic or metal resistance gene expression. Topical 38% silver diamine fluoride is effective and safe in arresting cavities in preschool children.Clinical significanceThe treatment is applicable to primary care practice and may reduce the burden of untreated tooth decay in the population