ABSTRACT The Large Volume Detector (LVD) has been continuously taking data since 1992 at the INFN Gran Sasso National Laboratory. The LVD is sensitive to neutrino bursts from gravitational stellar ...collapses with full detection probability over the Galaxy. We have searched for neutrino bursts in LVD data taken over 7,335 days of operation. No evidence of neutrino signals has been found between 1992 June and 2013 December. The 90% C.L. upper limit on the rate of core collapse and failed supernova explosions out to distances of 25 kpc is found to be 0.114 yr−1.
The influence of colonization of the pea (Pisum sativum L.) by aerobic methylobacteria of five different species (Methylophilus flavus Ship, Methylobacterium extorquens G10, Methylobacillus arboreus ...Iva, Methylopila musalis MUSA, Methylopila turkiensis Sidel) on plant resistance to paraquat-induced stresses has been studied. The normal conditions of pea colonization by methylobacteria were characterized by a decrease in the activity of antioxidant enzymes (superoxide dismutase, catalase, and peroxidases) and in the concentrations of endogenous H2O2, proline, and malonic dialdehyde, which is a product of lipid peroxidation and indicator of damage to plant cell membranes, and an increase in the activity of the photosynthetic apparatus (the content of chlorophylls a, b and carotenoids). In the presence of paraquat, the colonized plants had higher activities of antioxidant enzymes, stable photosynthetic indices, and a less intensive accumulation of the products of lipid peroxidation as compared to noncolonized plants. Thus, colonization by methylobacteria considerably increased the adaptive protection of pea plants to the paraquat-induced oxidative stress.
Antifungal activity (Candida albicans, Candida krusei) of some substituted quinolinium derivatives has been investigated. It was established that the most perspective compound for detail ...investigation of antifungal activity by labeled biomarkers method was N-phenylbenzoquinaldinium tetrafluoroborate.
A diverse series of 43 novel “soft antimicrobials” based on quaternary ammonium pyridoxine derivatives which include six-membered acetals and ketals of pyridoxine bound via cleavable linker moieties ...(amide, ester) with a fragment of fatty carboxylic acid was designed. Nine compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains with MIC values comparable with reference antiseptics miramistin, benzalkonium chloride and chlorohexidine. On various clinical isolates, the lead compounds 6i and 12a exhibited antibacterial activity comparable with that of benzalkonium chloride while higher than that of miramistin. Moreover, 6i and 12a were able to kill bacteria embedded into the matrix of mono- and dual species biofilms. The treatment of bacterial cells by either 6i and 12a lead to fast depolarization of the membrane suggesting that the membrane is an apparent molecular target of compounds. 6i and 12a were non mutagenic neither in SOS-chromotest nor in Ames test and non-toxic in vivo at acute oral (LD50 > 2000 mg/kg) and cutaneous administration (LD50 > 2500 mg/kg) on mice. Taken together, our data allow suggesting described active compounds as promising starting point for the new antibacterial agents development.
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•Design and synthesis of novel “soft antimicrobials” based on quaternary ammonium pyridoxine derivatives.•The compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains.•Lead compounds 6i and 12a exhibited promising antibacterial activity on clinical isolates and bacterial biofilms.•Lead compounds 6i and 12a were non mutagenic neither in SOS-chromotest nor in Ames test and non-toxic in vivo.
A series of 108 novel quaternary bis-ammonium pyridoxine derivatives carrying various substituents at the quaternary nitrogen's and acetal carbon was synthesized. Thirteen compounds exhibited ...antibacterial and antifungal activity (minimum inhibitory concentration (MIC) 0.25-16 µg/mL) comparable or superior than miramistin, benzalkonium chloride, and chlorhexidine. A strong correlation between the lipophilicity and antibacterial activity was found. The most active compounds had logP values in the range of 1-3, while compounds with logP > 6 and logP < 0 were almost inactive. All active compounds demonstrated cytotoxicity comparable with miramistin and chlorhexidine on HEK-293 cells and were three-fold less toxic when compared to benzalkonium chloride. The antibacterial activity of leading compound
on biofilm-embedded
,
,
or
was comparable or even higher than that of the benzalkonium chloride. In vivo
was considerably less toxic (LD
1705 mg/kg) than benzalkonium chloride, miramistine, and chlorhexidine at oral administration on CD-1 mice. An aqueous solution of
(0.2%) was shown to be comparable to reference drugs efficiency on the rat's skin model. The molecular target of
seems to be a cellular membrane as other quaternary ammonium salts. The obtained results make the described quaternary bis-ammonium pyridoxine derivatives promising and lead molecules in the development of the new antiseptics with a broad spectrum of antimicrobial activity.
We report herein the design, synthesis and biological evaluation of series of 7-substituted fluoroquinolones with pyridoxine derivatives. In vitro screening of antibacterial activity and toxicity of ...39 synthesized fluoroquinolones defined compounds 7 and 28 as lead compounds for further investigations. On various clinical isolates lead compounds 7 and 28 exhibited antibacterial activity comparable with reference fluoroqinolones. Mutagenic effects haven't been observed for these compounds in SOS-chromotest. Compound 7 are non-toxic in vivo on mice (LD50 > 2000 mg/kg, oral) and rats (LD50 > 2000 mg/kg, oral). Compound 28 was more toxic (LD50 = 474 mg/kg, oral, mice). Moreover compound 7 showed greater in vivo efficacy compared to ciprofloxacin in a murine model of staphylococcal sepsis. Taken together the described active compound are promising candidate for preclinical trials.
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•Synthesis and biological evaluation of fluoroquinolones containing a pyridoxine derivatives moiety•The compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains.•Lead compound 7 is non-toxic in vivo on mice (LD50 > 2000 mg/kg, oral) and rats (LD50 > 2000 mg/kg, oral) and showed greater in vivo efficacy compared to ciprofloxacin in a murine model of staphylococcal sepsis.
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•The benchmarking of star-shaped organic semiconductors as HTMs for perovskite solar cells is presented.•The triazatruxene-based compounds are promising hole-transporting materials to ...enable 20% device efficiency without doping.•An optimal range of HOMO energy level of small-molecule hole transporting material for MAPbI3 is found experimentally.•Photoluminescence quenching is proportionally related to device efficiency in the absence of the intrinsic photoluminescence.
Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nuclear recoils induced by the scattering of Weakly ...Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also prove the galactic origin of Dark Matter with an unambiguous signal-to-background separation. Indeed, the angular distribution of recoiled nuclei is centered around the direction of the Cygnus constellation, while the background distribution is expected to be isotropic. Current directional experiments are based on gas TPC whose sensitivity is limited by the small achievable detector mass. In this paper we present the discovery potential of a directional experiment based on the use of a solid target made of newly developed nuclear emulsions and of optical read-out systems reaching unprecedented nanometric resolution.
The distribution and phylogeny of the GroEL chaperonin genes in the type strains of all described species of pink-pigmented methylotrophic bacteria (PPFM) belonging to the genera
Methylobacterium
and
...Methylorubrum
were analyzed. Half of the bacterial strains tested (38 out of 69) were found to possess multiple
groEL
genes. Analysis of their translated amino acid sequences and promoter regions preceding the
groESL
operons that include them demonstrated that the GroEL chaperonins of these methylotrophs form three similarity groups typical of PPFM. The largest of these (GroEL1) combines, apparently, essential housekeeping chaperonins, and the other two consist of additional separately clustered proteins that differ in the composition of the elements regulating their gene expression. The strains encoding proteins of the GroEL2 group were isolated from various environments, including those contaminated with industrially produced C
1
-compounds, while bacteria possessing GroEL3-like chaperonins are predominantly plant symbionts. It has been proposed that GroEL3 proteins may be involved in phytosymbiotic processes, whereas GroEL2 chaperonins can participate in response to specific stresses experienced by host cells in their habitats. At the same time, the GroEL chaperonin of
Methylobacterium brachiatum
B0021
T
, atypical for PPFM, seem to be intended for folding of dinuclear iron monooxygenase, in whose gene cluster it is encoded. Further testing of these assumptions should elucidate the roles of multiple GroEL chaperonins in PPFM and allow more complete use of their biotechnological potential as plant growth stimulants and biodegradation/bioremediation agents.
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