Cloning and partial characterization of three small cryptic plasmids from Bacillus thuringiensis.

The strain H1.1 of Bacillus thuringiensis var. thuringiensis harbors three small cryptic plasmids: pGI1, pGI2, and pGI3 (8.2, 9.2, and 10.6 kb, respectively). Two of these plasmids (i.e., pGI2 and pGI3) were successfully cloned in their entirety into the vector pBR322, whereas only overlapping DNA fragments covering pGI1 were obtained in Escherichia coli. A curing-hybridization technique was used to obtain isolates of B. thuringiensis missing one or another small cryptic plasmid. These derivatives were examined for any change in a phenotypic trait, but no specific function could be assigned to one of these plasmids. Hybridization and restriction mapping data revealed that the transposon Tn4430 accounts for 45% of the pGI2 plasmid DNA

A 1,3-diaza-2,4-distannacyclobutanediide: Synthesis, structure, and bonding

A combined experimental and computational study throws light on the structure and bonding of the diamagnetic {(SnN)2} compound [{Sn{N(SiMe3)}Cl}2] (see picture), obtained from the reaction of [Sn{N(SiMe3}2)(µ-Cl)]2 with AgOCN

Evidence for different molecular parameters in head and neck squamous cell carcinoma of nonsmokers and nondrinkers:Systematic review and meta-analysis on HPV, p16, and TP53

Background The goal of this review was to present an overview of the currently identified molecular parameters in head and neck squamous cell carcinoma (HNSCC) of nonsmokers and nondrinkers (NSND). Methods Following the PRISMA guidelines, a systematic search was performed using the electronic databases PubMed, Embase, and Google Scholar. Results Of the 902 analyzed unique studies, 74 were included in a quantitative synthesis and 24 in a meta-analysis. Human papillomavirus (HPV) was reported as a molecular parameter in 38 studies, followed by p16 and TP53 (23 and 14 studies, respectively). The variety of other molecular parameters concerned sporadic findings in small numbers of NSND. Conclusions HNSCC in NSND is more often related to HPV and p16 overexpression compared to tumors of smokers-drinkers. In a third of virus-negative tumors, TP53 mutations were detected with a mutational profile associated with aging and ultraviolet light exposure rather than to tobacco consumption

Evidence for different molecular parameters in head and neck squamous cell carcinoma of nonsmokers and nondrinkers: Systematic review and meta-analysis on HPV, p16, and TP53

Background The goal of this review was to present an overview of the currently identified molecular parameters in head and neck squamous cell carcinoma (HNSCC) of nonsmokers and nondrinkers (NSND). Methods Following the PRISMA guidelines, a systematic search was performed using the electronic databases PubMed, Embase, and Google Scholar. Results Of the 902 analyzed unique studies, 74 were included in a quantitative synthesis and 24 in a meta-analysis. Human papillomavirus (HPV) was reported as a molecular parameter in 38 studies, followed by p16 and TP53 (23 and 14 studies, respectively). The variety of other molecular parameters concerned sporadic findings in small numbers of NSND. Conclusions HNSCC in NSND is more often related to HPV and p16 overexpression compared to tumors of smokers-drinkers. In a third of virus-negative tumors, TP53 mutations were detected with a mutational profile associated with aging and ultraviolet light exposure rather than to tobacco consumption