Search results for "biologia generale"

Antimicrobial effect of cyclodextrin-based nanodevices capable of antibiotic release

2018

Triiodothyronine-Induced Shortening of Chromatin Repeat Length in Neurons Cultured in a Chemically Denned Medium

1987

Abstract: At the time of terminal differentiation, mammalian cortical neurons undergo a dramatic change in the structural organization of their chromatin: the nucleosomal repeat length shortens from ∼200 base pairs in fetuses to a value of 165 base pairs after birth. These events occur several days after the end of neuronal proliferation. Previously, we reported that rat cortical neurons cultured in a very selective synthetic medium were not yet programmed to these events at the end of mitotic cycles. Herein, we report that addition of triiodothyronine to neuronal cultures induces a shortening of the chromatin repeat length comparable to the natural one. Copyright © 1987, Wiley Blackwell. A…

Phosphate-controlled regulators for the biosynthesis of the dalbavancin precursor A40926

2008

Phenotypic and genotypic characterization of root nodules rhizobia of Medicago littoralis Rhode and Melilotus indicus (L.) All. growing in the Oasis …

2015

Forty rhizobial strains were isolated from root nodules of Medicago littoralis Rhode and Melilotus indicus (L.) harvested from the sandy soils of Touggourt’s oases in the Oued Righ Valley, Algerian Sahara. The isolates were studied for their cultural, biochemical and symbiotic effectiveness. All of them were fast-growing bacteria; utilized a wide range of carbon sources, produced abundant extracellular polysaccharides, tolerated high concentrations of NaCl (up to 2.5 %), grew at temperatures between 28 and 45 °C and at pH values between 4.5 and 9. The isolates were sensitive to the antibiotics kanamycin, tetracycline and rifampicin but showed resistance to neomycin and erythromycin. All the…

Microbiological and safety evaluation of green table olives marketed in Italy

2011

The microbiological and safety conditions of green table olives sold on the Italian market were evaluated on 40 samples, 20 loose and 20 packed in containers, purchased at street markets and supermarkets. The olives were analyzed for microflora and food safety indices, and for aflatoxin B1 and ochratoxin A occurrence, and the results showed acceptable security. There was wide heterogeneity in the microflora, the numerical values being in relation to the olive type. The microbial population was dominated by the yeasts and lactic bacteria responsible for the fermentation process, and their numbers, together with the metabolic activity, led to conditions unfavorable for the development of path…

CHANGE IN VOLUME AND MORPHOLOGY IN CULTURES OF OLEISPIRA ANTARCTICA AS A FUNCTION OF TEMPERATURE AND SUBSTRATES USED

2015

Bacterial population under nutritional and physic stress react in order to adequate cell metabolism and physiology to stressful conditions. One of the most frequently observed behaviours in the stress-starvation response of gram-negative bacteria is the size reduction and cell morphology conversion from rod to resistant shape-form. In such framework, we report here on morphology (cell volume and cell shape) variations in psychrophilic strain Oleispira antarctica RB 8T under different growth temperature and different hydrocarbons mixtures sources. Six different hydrocarbons mixtures (car commercial diesel, commercial crude oil engine; 2 different bilge waters, military jet fuel and crude oil…

Isolation Of Organophosphorus Pesticides Bacteria Degraders From Agricultural Sicilian Soils.

2009

Pesticides are generally categorized according to their great or low persistence in the environment. Although new biological, chemical, and management technologies are continually being developed to provide more sustainable production alternatives, it is expected that the use of pesticides will continue to be an essential tool in the integrated pest management. Pesticides are biologically active compounds designed to interfere with metabolic processes. Organophosphorus pesticides (OP) pesticides are less persistent than Organochlorine pesticides (OC), they are not without environmental risks, so this justifies the social concern about their level in different kind of matrices like soil, wat…

Molecular characterization of biofilm-forming S.aureus field isolates and their treatment

2008

Characterization of the bacterial community isolated from a High Middle Age soil sample dated since 980 AD

2016

Characterization of the microbiota from coelomic fluid of the sea urchin Paracentrotus lividus

2016

The study of the microbiota is a subject of considerable and growing interest since it is drawing new important perspectives in the life sciences concerning the functional relationships between metazoans and microbial cells. In fact, it has already shown that the endogenous microbial community affects various physiological activities of multicellular organisms. The coelomic cavity of echinoderms contains a fluid in which coelomocytes are reported to exert immune functions like phagocytosis, opsonization and production of antimicrobial agents against marine bacteria [1, 2]. However, up to day nothing is known about the endogenous bacterial population of coelomic fluid. We focused on this iss…