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31.
Thiago Olitta Basso Fernanda Sgarbosa Gomes Mario Lucio Lopes Henrique Vianna de Amorim Gillian Eggleston Luiz Carlos Basso 《Antonie van Leeuwenhoek》2014,105(1):169-177
Bacterial contamination during industrial yeast fermentation has serious economic consequences for fuel ethanol producers. In addition to deviating carbon away from ethanol formation, bacterial cells and their metabolites often have a detrimental effect on yeast fermentative performance. The bacterial contaminants are commonly lactic acid bacteria (LAB), comprising both homo- and heterofermentative strains. We have studied the effects of these two different types of bacteria upon yeast fermentative performance, particularly in connection with sugarcane-based fuel ethanol fermentation process. Homofermentative Lactobacillus plantarum was found to be more detrimental to an industrial yeast strain (Saccharomyces cerevisiae CAT-1), when compared with heterofermentative Lactobacillus fermentum, in terms of reduced yeast viability and ethanol formation, presumably due to the higher titres of lactic acid in the growth medium. These effects were only noticed when bacteria and yeast were inoculated in equal cell numbers. However, when simulating industrial fuel ethanol conditions, as conducted in Brazil where high yeast cell densities and short fermentation time prevail, the heterofermentative strain was more deleterious than the homofermentative type, causing lower ethanol yield and out competing yeast cells during cell recycle. Yeast overproduction of glycerol was noticed only in the presence of the heterofermentative bacterium. Since the heterofermentative bacterium was shown to be more deleterious to yeast cells than the homofermentative strain, we believe our findings could stimulate the search for more strain-specific antimicrobial agents to treat bacterial contaminations during industrial ethanol fermentation. 相似文献
32.
Luciana Filgueira Pereira Elisa Lucatti Luiz Carlos Basso Marcos Antonio de Morais Jr 《Antonie van Leeuwenhoek》2014,105(3):481-489
The yeast Dekkera bruxellensis is considered to be very well adapted to industrial environments, in Brazil, USA, Canada and European Countries, when different substrates are used in alcoholic fermentations. Our previous study described its fermentative profile with a sugarcane juice substrate. In this study, we have extended its physiological evaluation to fermentation situations by using sugarcane molasses as a substrate to replicate industrial working conditions. The results have confirmed the previous reports of the low capacity of D. bruxellensis cells to assimilate sucrose, which seems to be the main factor that can cause a bottleneck in its use as fermentative yeast. Furthermore, the cells of D. bruxellensis showed a tendency to deviate most of sugar available for biomass and organic acids (lactic and acetic) compared with Saccharomyces cerevisiae, when calculated on the basis of their respective yields. As well as this, the acetate production from molasses medium by both yeasts was in marked contrast with the previous data on sugarcane juice. Glycerol and ethanol production by D. bruxellensis cells achieved levels of 33 and 53 % of the S. cerevisiae, respectively. However, the ethanol yield was similar for both yeasts. It is worth noting that this yeast did not accumulate trehalose when the intracellular glycogen content was 30 % lower than in S. cerevisiae. The lack of trehalose did not affect yeast viability under fermentation conditions. Thus, the adaptive success of D. bruxellensis under industrial fermentation conditions seems to be unrelated to the production of these reserve carbohydrates. 相似文献
33.
Valentina Giorgio Maria Eugenia Soriano Emy Basso Elena Bisetto Giovanna Lippe Michael A. Forte Paolo Bernardi 《BBA》2010,1797(6-7):1113-1118
Cyclophilins are a family of peptidyl-prolyl cis–trans isomerases whose enzymatic activity can be inhibited by cyclosporin A. Sixteen cyclophilins have been identified in humans, and cyclophilin D is a unique isoform that is imported into the mitochondrial matrix. Here we shall (i) review the best characterized functions of cyclophilin D in mitochondria, i.e. regulation of the permeability transition pore, an inner membrane channel that plays an important role in the execution of cell death; (ii) highlight new regulatory interactions that are emerging in the literature, including the modulation of the mitochondrial F1FO ATP synthase through an interaction with the lateral stalk of the enzyme complex; and (iii) discuss diseases where cyclophilin D plays a pathogenetic role that makes it a suitable target for pharmacologic intervention. 相似文献
34.
Navaglia F Fogar P Greco E Basso D Stefani AL Mazza S Zambon CF Habeler W Altavilla G Amadori A Cecchetto A Plebani M 《The International journal of biological markers》2003,18(2):130-138
AIMS: The aims of this study were 1) to investigate the mRNA pattern of CD44 variants in three primary (MIA PaCa 2, PANC-1, PSN-1) and two metastatic (CAPAN-1, SUIT-2) pancreatic cancer (PC) cell lines; 2) to ascertain whether the genetic transfer of CD44s and CD44v10 modifies the adhesion of PC cells to the extracellular matrix (ECM) in vitro and their metastatic behavior in vivo. METHODS: CD44 mRNA analysis was done by means of RT-PCR. Adhesion to ECM the was assessed using coated microtiter plates. For the study of CD44v10 insertion in the CAPAN-1 line, liposome-mediated DNA transfer was used. SCID mice were employed for in vivo experiments. RESULTS: CD44v10 mRNA was not expressed by the CAPAN-1 nor by four of the six SUIT-2-derived clones. The stable expression of CD44v10 by modified CAPAN-1 significantly enhanced fibronectin adhesion. Mice without either liver or pancreatic metastases were more frequently found among the animals injected with modified (CD44v10 expressing) than with non-modified CAPAN-1. CONCLUSIONS: 1) It is possible to differentiate between metastatic and non-metastatic PC cells on the basis of CD44v10 expression; 2) CD44v10 seems to be involved in mediating fibronectin adhesion in vitro and in counteracting metastases in vivo. 相似文献
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36.
Romeo Romagnoli Pier Giovanni Baraldi Olga Cruz-Lopez Carlota Lopez Cara Maria Dora Carrion Jan Balzarini Ernest Hamel Giuseppe Basso Roberta Bortolozzi Giampietro Viola 《Bioorganic & medicinal chemistry letters》2010,20(9):2733-2739
In a continuing study of hybrid compounds containing the α-bromoacryloyl moiety as potential anticancer drugs, we synthesized a novel series of hybrids 4a–h, in which this moiety was linked to a 1,5-diaryl-1,4-pentadien-3-one system. Many of the conjugates prepared (4b, 4c, 4e and 4g) demonstrated pronounced, submicromolar antiproliferative activity against four cancer cell lines. Moreover, compound 4b induced apoptosis through the mitochondrial pathway and activated caspase-3 in a concentration-dependent manner. 相似文献
37.
The role of brain‐derived neurotrophic factor in learned fear processing: an awake rat fMRI study 下载免费PDF全文
A. P. Harris R. J. Lennen N. M. Brydges M. A. Jansen C. R. Pernet H. C. Whalley I. Marshall S. Baker A. M. Basso M. Day J. Hall 《Genes, Brain & Behavior》2016,15(2):221-230
Brain‐derived neurotrophic factor (BDNF) signaling is implicated in the etiology of many psychiatric disorders associated with altered emotional processing. Altered peripheral (plasma) BDNF levels have been proposed as a biomarker for neuropsychiatric disease risk in humans. However, the relationship between peripheral and central BDNF levels and emotional brain activation is unknown. We used heterozygous BDNF knockdown rats (BDNF+/?) to examine the effects of genetic variation in the BDNF gene on peripheral and central BDNF levels and emotional brain activation as assessed by awake functional magnetic resonance imaging (fMRI). BDNF+/? and control rats were trained to associate a flashing light (conditioned stimulus; CS) with foot‐shock, and brain activation in response to the CS was measured 24 h later in awake rats using fMRI. Central and peripheral BDNF levels were decreased in BDNF+/? rats compared with control rats. Activation of fear circuitry (amygdala, periaqueductal gray, granular insular) was seen in control animals; however, activation of this circuitry was absent in BDNF+/? animals. Behavioral experiments confirmed impaired conditioned fear responses in BDNF+/? rats, despite intact innate fear responses. These data confirm a positive correlation [r = 0.86, 95% confidence interval (0.55, 0.96); P = 0.0004] between peripheral and central BDNF levels and indicate a functional relationship between BDNF levels and emotional brain activation as assessed by fMRI. The results demonstrate the use of rodent fMRI as a sensitive tool for measuring brain function in preclinical translational studies using genetically modified rats and support the use of peripheral BDNF as a biomarker of central affective processing. 相似文献
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39.
Banfi L Basso A Damonte G De Pellegrini F Galatini A Guanti G Monfardini I Riva R Scapolla C 《Bioorganic & medicinal chemistry letters》2007,17(5):1341-1345
The synthesis of new conformationally biased cyclic pentapeptides, incorporating the RGD sequence, and built around a tetrahydroazoninone scaffold, is reported. They exhibit interesting activity towards integrin alphaVbeta3 and a remarkable selectivity in comparison with integrin alphaVbeta5. 相似文献
40.
In Chile and Uruguay, the gregarious Pteromalidae (Monoksa dorsiplana) has been discovered emerging from seeds of the persistent pods of Acacia caven attacked by the univoltin bruchid Pseudopachymeria spinipes. We investigated the potential for mass rearing of this gregarious ectoparasitoid on an alternative bruchid host, Callosobruchus maculatus, to use it against the bruchidae of native and cultured species of Leguminosea seeds in South America.The mass rearing of M. dorsiplana was carried out in a population cage where the density of egg-laying females per infested seed was increased from 1:1 on the first day to 5:1 on the last (fifth) day. Under these experimental conditions egg-clutch size per host increased, and at the same time the mortality of eggs laid also increased. The density of egg-laying females influenced the sex ratio which tended towards a balance of sons and daughters, in contrast to the sex ratio of a single egg-laying female per host (1 son to 7 daughters). The mean weight of adults emerging from a parasitized host was negatively correlated with the egg-clutch size, i.e. as egg-clutch size increased, adult weight decreased.All these results show that mass rearing of the gregarious ectoparasitoid M. dorsiplana was possible under laboratory conditions on an alternative bruchid host C. maculatus. As M. dorsiplana is a natural enemy of larval and pupal stages of bruchidae, the next step was to investigate whether the biological control of bruchid C. maculatus was possible in an experimental structure of stored beans. 相似文献