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31.
The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, as Enterococcus casseliflavus, Enterococcus faecium, Enterococcus faecalis, Enterococcus lactis, Lactobacillus delbrueckii, and Streptococcus thermophilus, while the other strains, all belonging to the genus Enterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions.  相似文献   
32.
Extracts from autoclaved maize culture ofFusarium tumidum strain R-5823 were toxic towardsArtemia salina. Bioassay-guided fractionation of the organic extract led to the isolation of the toxic compound that was identified as the trichothecene toxin neosolaniol (NEOS) by1H,13C nuclear magnetic resonance spectroscopy and low-resolution electronic impact mass spectrometry. The amount of NEOS produced by the strain R-5823 was 300 mg/kg maize culture. NEOS was also detected by HPLC in cultures of four out of seven additional strains ofF. tumidum andGibberella tumida with different origin, in amounts ranging from 1 to 311 mg/kg. This is the first report on the production of a trichothecene toxin byF. tumidum.  相似文献   
33.
Cedrus libani are widely used as traditional medicine in Lebanon for treatment of different infection diseases. In the present study we reported the phytochemical composition analyzed by GC-MS of wood essential oil and cones and leaves ethanol extracts. The main components of wood essential oil were himachalol (22.50%), beta-himachalene (21.90%), and alpha-himachalene (10.50%). Leaves ethanol extract was characterized by a high content of germacrene d (29.40%). The same extract obtained from cones essentially contained alpha-pinene (51.0%) and beta-myrcene (13.0%). Moreover, we investigated extracts, essential oil, and identified compounds for their in vitro antiviral activities against herpes simplex virus type 1 (HSV-1). Cytotoxicity was evaluated by MTT assay in Vero cells. Cones and leaves ethanol extracts exhibited an interesting activity with IC50 of 0.50 and 0.66 mg/ml, respectively, at non-cytotoxic concentration. A comparable activity was found when essential oil was tested (IC50 of 0.44 mg/ml).  相似文献   
34.
New copper(I) complexes of the type [H(2)B(tz(NO2))(2)]Cu[PR(3)](2) (1-5), [H(2)B (tz(NO2))(2)]Cu[dppe] (6) and [H(2)B(tz(NO2))(2)]Cu[PR(3)] (7, 8) have been synthesized from the reaction of CuCl, potassium dihydrobis(3-nitro-1,2,4-triazol-1-yl)borate, K[H(2)B (tz(NO2))(2)], and mono- or bi-dentate tertiary phosphanes. The complexes obtained have been characterized by elemental analyses and FT-IR in the solid state, and by NMR ((1)H and (31)P{(1)H}) spectroscopy in solution. Selected complexes 1, 3 and 5 have also been tested against a panel of several human tumor cell lines in order to evaluate their cytotoxic activity. Complexes 1 and 5 showed IC(50) values appreciably lower than those exhibited by cisplatin, the most used metal-based antitumor drug. It is worth noting that all three tested Cu(I) complexes appear to be particularly effective against A549 carcinoma cells that are resistant to cisplatin treatment.  相似文献   
35.
Abstract

A Red List of all 108 Pezizomycotina (Ascomycota) species recorded in Umbria Region (central Italy) is provided. According to the IUCN categories and criteria, 60.18% of the assessed species are classified as threatened, whereas 12.96% are Near Threatened (NT), 1.86% are Least Concerned (LC) and a noteworthy amount of 25% are Data Deficient (DD). As a consequence of the downlisting applied to the majority of the assessed taxa, according to the guidelines for application of IUCN red list criteria at Regional level, only 1.54% of the threatened species is Critically Endangered (CR), while 46.15% are Endangered (EN) and 52.31% are Vulnerable (VU). Given that the present work represents the first complete regional red list of Pezizomycotina in Italy, and that a national, as well as a European red list do not exist to date, it could be considered as a case study for other Italian Regions as well as for other European countries, aiming at the compilation of a national and European red list of this fungal group mostly overlooked in conservation strategies.  相似文献   
36.
37.
It is now clear that mitochondrial defects are associated with a large variety of clinical phenotypes. This is the result of the mitochondria's central role in energy production, reactive oxygen species homeostasis, and cell death. These processes are interdependent and may occur under various stressing conditions, among which low oxygen levels (hypoxia) are certainly prominent. Cells exposed to hypoxia respond acutely with endogenous metabolites and proteins promptly regulating metabolic pathways, but if low oxygen levels are prolonged, cells activate adapting mechanisms, the master switch being the hypoxia-inducible factor 1 (HIF-1). Activation of this factor is strictly bound to the mitochondrial function, which in turn is related with the oxygen level. Therefore in hypoxia, mitochondria act as [O2] sensors, convey signals to HIF-1directly or indirectly, and contribute to the cell redox potential, ion homeostasis, and energy production. Although over the last two decades cellular responses to low oxygen tension have been studied extensively, mechanisms underlying these functions are still indefinite. Here we review current knowledge of the mitochondrial role in hypoxia, focusing mainly on their role in cellular energy and reactive oxygen species homeostasis in relation with HIF-1 stabilization. In addition, we address the involvement of HIF-1 and the inhibitor protein of F1F0 ATPase in the hypoxia-induced mitochondrial autophagy.  相似文献   
38.
In vitro micropropagation by direct organogenesis and somatic embryogenesis via callus was developed for Crambe tataria (Brassicaceae). C. tataria is an endemic species of the Pontic-Pannonic region, but it is also present in Italy, where it is localized in Friuli on a characteristic grassland formation, called “magredi”. C. tataria is regarded as an endangered species. Leaf and root explants were subjected to plant regulator treatments, which invoked different morphogenic responses. Leaf explants produced more callus than root explants and a higher amount of callus was obtained with 1 mg l−1 2,4-D in combination with 2 mg l−1 Kin. Somatic embryogenesis was obtained in calli maintained in a delayed subculture regime on media containing BAP in combination with NAA. Root explants cultured with BAP combined with NAA developed adventitious rosette shoots. Shoots rooted on half-strength MS media, and the number of roots per plantlet and their length were heavily dependent on sucrose content. The in vitro regenerated plantlets were acclimatized ex vitro and a mean of 50% of the plantlets survived and showed a true-to-type growth habit. This study describes the development of two in vitro micropropagation protocols, via direct organogenesis and via embryogenesis from callus, that are the basis for the application of in vitro tools for the establishment of basal collections with representative genetic diversity and for the long-term storage of plant genetic material.  相似文献   
39.
To clarify the possible molecular mechanism of cation unit conductance of poly(D ,L -proline) across lipidic membranes, the structure and conformation of tetraproline derivatives with different configurational sequences in solid state, as well as in solution and in the presence of alkali and alkali-earth ions, were investigated using x-ray analysis, CD, and nmr spectroscopy. The tetraproline derivatives Boc(D -Pro-L -Pro-L -Pro-D -Pro)OBg and Boc(L -Pro)4OBg show very different conformational versatilities in solutions as well as different propensities to form complexes with Ca2+ ion. This is interpreted, based on previous evidence, as due to different abilities to form ion complexing cavities. © 1998 John Wiley & Sons, Inc. Biopoly 45: 257–267, 1998  相似文献   
40.
We report a case of a reciprocal translocation between the long arms of the 2 and 10 chromosomes observed in a 14-year-old male with mild mental impairment, compulsive and obsessive behavior. The apparently balanced translocation was characterized by fluorescence in situ hybridization and the karyotype was 46, XY, t(2;10)(q24;q22). The way by balanced chromosomal translocations can lead to a disease phenotype are reviewed and discussed.  相似文献   
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