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991.
Silva Larissa Cardoso de Souza Lago Heitor Rocha Márcia Oliveira Terra de Oliveira Vanessa Sales Laureano-Melo Roberto Stutz Evandro Toledo Gerhardt de Paula Breno Pereira Martins José Francisco Pereira Luchese Rosa Helena Guerra André Fioravante Rodrigues Paula 《Probiotics and antimicrobial proteins》2021,13(3):698-708
Probiotics and Antimicrobial Proteins - This study aimed to produce a probiotic-containing functional wheat beer (PWB) by an axenic culture system with potential probiotic Saccharomyces cerevisiae... 相似文献
992.
Igor Martins Alves Melo Magda Rogéria Pereira Viana Breno Pupin Tanmoy Tapobrata Bhattacharjee Renata de Azevedo Canevari 《Biochemistry and Biophysics Reports》2021
BackgroundApproximately 70% of cervical carcinoma cases show the presence of high-risk Human Papilloma Virus (HPV), especially HPV-16 and HPV-18, and can be used to stratify high risk patients from low risk and healthy. Currently, molecular biology techniques such as polymerase chain reaction (PCR) are used to identify the presence of virus in patient samples. While the methodology is highly sensitive, it is labor intensive and time-consuming. Alternative techniques, such as vibrational spectroscopy, has been suggested as a possible rapid alternative. Therefore, in this study, we evaluate the efficiency of cervical fluid Fourier Transform Infrared spectroscopy (FTIR) in patient risk stratification informed by PCR.MethodsCervical fluid samples (n = 91) were obtained from patients who have undergone routine Papanicolaou (Pap) test. Viral genome was identified and classified as high/low-risk by PCR-Restriction Fragment Length Polymorphism (PCR-RFLP). FTIR spectra were acquired from samples identified by PCR-RFLP as No-HPV (n = 10), high-risk HPV (n = 7), and low-risk HPV (n = 7).ResultsOf the 91 samples, was detected the viral genome by PCR in 36 samples. Of these 36 samples, nine samples were identified to contain high-risk HPV (HR-HPV) and nine samples were found to have low-risk HPV (LR-HPV). The FTIR spectra acquired from No-HPV, LR-HPV, and HR-HPV showed differences in 1069, 1437, 1555, 1647, 2840, 2919, and 3287 cm-1 bands. Principal Component Analysis (PCA) showed distinct clusters for No-HPV and HR-HPV and No-HPV and LR-HPV, but there was significant overlap in the clusters of HR-HPV and LR-HPV. PCA-Linear Discriminant Analysis (PC-LDA) after Leave One Out Cross Validation (LOOCV) classified No-HPV from HR-HPV and No-HPV from LR-HPV with 100% efficiency in the 1400-1800 cm-1 spectral range. LOOCV classifications for LR-HPV and HR-HPV from each other were 71 and 75%, respectively, in the 2800-3400 cm-1 spectral range.ConclusionsThe results highlight the high sensitivity of PCR-RFLP in HPV identification and show that FTIR can classify samples identified as healthy, low, and high-risk samples by PCR-RFLP.General significanceWe show the possibility of using FTIR for initial cervical cancer risk stratification followed by detailed PCR-RFLP investigations for suspect cases. 相似文献
993.
Araújo TG Leite AC Martins da Fonseca CS Carvalho BM Schuler AR Lima VL 《Journal of physiology and biochemistry》2011,67(3):371-379
Currently, there are no reports in the literature demonstrating any animal model that ingests one of the fattiest animal food
source, the bovine brain. We hypothesized that a high-fat diet (HFD), based on dried bovine brain, could be used to develop
an animal model possessing a spectrum of insulin resistance-related features. The HFD was formulated with 40% dried bovine
brain plus 16.4% butter fat, prepared in-house. Furthermore, the diet contained 52% calories as fat and 73% of total fatty acids were saturated. Swiss mice weighing about
40 g were assigned to two dietary groups (n = 6/group), one group received a standard chow diet and the other was given HFD for 3 months. The body weight and biochemical
parameters of the animals were measured initially and at monthly intervals until the end of the experiment. Animals fed on
a HFD showed a significant increase in the body and adipose tissue weight, serum total cholesterol and triglyceride levels,
when compared with mice fed on the control diet. Additionally, the HFD group showed higher circulating levels of liver transaminases,
such as alanine aminotransferase and aspartate aminotransferase, compared with the control group. Finally, to illustrate the
usefulness of this model, we report that the HFD induced mild hyperglycemia, fasting hyperinsulinemia, and increased the homeostasis
model of assessment (HOMA-IR), in comparison with the control group. In conclusion, our results show that HFD, based on dried
bovine brain, causes insulin resistance-related metabolic disturbances. Thus, this may be a suitable model to study disturbances
in energy metabolism and their consequences. 相似文献
994.
do Carmo FL dos Santos HF Martins EF van Elsas JD Rosado AS Peixoto RS 《Journal of microbiology (Seoul, Korea)》2011,49(4):535-543
Most oil from oceanic spills converges on coastal ecosystems, such as mangrove forests, which are threatened with worldwide
disappearance. Particular bacteria that inhabit the rhizosphere of local plant species can stimulate plant development through
various mechanisms; it would be advantageous if these would also be capable of degrading oil. Such bacteria may be important
in the preservation or recuperation of mangrove forests impacted by oil spills. This study aimed to compare the bacterial
structure, isolate and evaluate bacteria able to degrade oil and stimulate plant growth, from the rhizospheres of three mangrove
plant species. These features are particularly important taking into account recent policies for mangrove bioreme-diation,
implying that oil degradation as well as plant maintenance and health are key targets. Fifty-seven morphotypes were isolated
from the mangrove rhizospheres on Bushneil-Haas (BH) medium supplemented with oil as the sole carbon source and tested for
plant growth promotion. Of this strains, 60% potentially fixed nitrogen, 16% showed antimicrobial activity, 84% produced siderophores,
51% had the capacity to solubilize phosphate, and 33% produced the indole acetic acid hormone. Using gas chromatography, we
evaluated the oil-degrading potential of ten selected strains that had different morphologies and showed Plant Growth Promoting
Rhizobacteria (PGPR) features. The ten tested strains showed a promising degradation profile for at least one compound present
in the oil. Among degrader strains, 46% had promising PGPR potential, having at least three of the above capacities. These
strains might be used as a consortium, allowing the concomitant degradation of oil and stimulation of mangrove plant survival
and maintenance. 相似文献
995.
Ricardo R. Rodrigues Vera L. Engel Marcelo Tabarelli José M. D. Torezan Sergius Gandolfi Antônio C. G. de Melo Paulo Y. Kageyama Márcia C. M. Marques André G. Nave Sebastião V. Martins Flávio B. Gandara Ademir Reis Luiz M. Barbosa Fabio R. Scarano 《Restoration Ecology》2011,19(6):690-695
Around the world, there is growing desire and momentum for ecological restoration to happen faster, with better quality, and in more extensive areas. The question we ask is how can laws and governmental regulations best contribute to effective, successful, and broad‐scale restoration? In the state of São Paulo, Brazil, there is a legal instrument (SMA 08‐2008) whose aim is to increase the effectiveness of tropical forest restoration projects in particular. It establishes, among other things, requirements regarding the minimum number of native tree species to be reached within a given period of time in restoration projects and the precise proportion of functional groups or threatened species to be included when reforestation with native species is used as a restoration technique. There are, however, two differing perspectives among Brazilian restoration ecologists on the appropriateness of such detailed legal rules. For some, the rules help increase the chances that mandatory projects of ecological restoration will succeed. For the other group, there is no single way to achieve effective ecosystem restoration, and the existing science and know‐how are far from sufficient to establish standardized technical and methodological norms or to justify that such norms be imposed. Both points of view are discussed here, aiming to help those developing new legislation and improving existing laws about ecological restoration. The precedents established in São Paulo, and at the federal level in Brazil, and the ongoing debate about those laws are worth considering and possibly applying elsewhere. 相似文献
996.
Soto FR Vuaden ER de Paula Coelho C Bonamin LV de Azevedo SS Benites NR de Barros FR Goissis MD Ortiz D'Ávila Assumpção ME Visintin JA Marques MG 《In vitro cellular & developmental biology. Animal》2011,47(3):205-209
It has been speculated that the homeopathic treatment of sperm cells in order to improve semen quality could be promising. However, few data is available and its use in spermatozoa requires investigation. It is well established that mitochondrial membrane potential is an important viability parameter of spermatozoa and it is intimately related to reproductive efficiency. In this manner, new technologies in order to improve the activity of sperm cells and, finally, the fecundity of swine herds are of extremely importance. Due to the lack of knowledge of homeopathic treatment effect on spermatozoa, the aim of the present study was to verify the effect of three different homeopathic treatments on viability of boar sperm cells. Three homeopathic treatments composed by Pulsatila CH6, Pulsatila and Avena CH6, Avena CH6 and one control treatment (sucrose) were added to diluted boar semen, which were cooled for 24 or 48 h. Interestingly, no positive effect of homeopathic treatments was observed over semen viability. However, it was demonstrated that the 24 h of cooling storage provided more viable sperm cells when compared to the 48-h period. This effect of storage period on sperm viability was assessed by intact plasmatic membrane, intact acrosome and mitochondrial membrane potential evaluation. 相似文献
997.
998.
Delahaye NF Rusakiewicz S Martins I Ménard C Roux S Lyonnet L Paul P Sarabi M Chaput N Semeraro M Minard-Colin V Poirier-Colame V Chaba K Flament C Baud V Authier H Kerdine-Römer S Pallardy M Cremer I Peaudecerf L Rocha B Valteau-Couanet D Gutierrez JC Nunès JA Commo F Bonvalot S Ibrahim N Terrier P Opolon P Bottino C Moretta A Tavernier J Rihet P Coindre JM Blay JY Isambert N Emile JF Vivier E Lecesne A Kroemer G Zitvogel L 《Nature medicine》2011,17(6):700-707
999.
S. Cebrat D. Stauffer J. S. Sá Martins S. Moss de Oliveira P. M. C. de Oliveira 《Theorie in den Biowissenschaften》2011,130(2):135-143
We have simulated the evolution of sexually reproducing populations composed of individuals represented by diploid genomes.
A series of eight bits formed an allele occupying one of 128 loci of one haploid genome (chromosome). The environment required
a specific activity of each locus, this being the sum of the activities of both alleles located at the corresponding loci
on two chromosomes. This activity is represented by the number of bits set to zero. In a constant environment the best fitted
individuals were homozygous with alleles’ activities corresponding to half of the environment requirement for a locus (in
diploid genome two alleles at corresponding loci produced a proper activity). Changing the environment under a relatively
low recombination rate promotes generation of more polymorphic alleles. In the heterozygous loci, alleles of different activities
complement each other fulfilling the environment requirements. Nevertheless, the genetic pool of populations evolves in the
direction of a very restricted number of complementing haplotypes and a fast changing environment kills the population. If
simulations start with all loci heterozygous, they stay heterozygous for a long time. 相似文献
1000.
The molecular mechanisms of host cell invasion by T. cruzi metacyclic trypomastigotes (MT), the developmental forms that initiate infection in the mammalian host, are only partially understood. Here we aimed at further identifying the target cell components involved in signalling cascades leading to MT internalization, and demonstrate for the first time the participation of mammalian target of rapamycin (mTOR). Treatment of human epithelial HeLa cells with mTOR inhibitor rapamycin reduced lysosomal exocytosis and MT invasion. Downregulation of phosphatidylinositol 3-kinase and protein kinase C also impaired exocytosis and MT internalization. The recombinant protein based on gp82, the MT surface molecule that mediates cell adhesion/invasion, induced exocytosis in HeLa cells. Such an effect has not previously been attributed to any T. cruzi surface molecule. Rapamycin treatment diminished gp82 binding as well. Cell invasion assays under conditions that promoted lysosome exocytosis, such as 1 h incubation in starvation medium PBS(++) , increased MT invasion, whereas pre-starvation of cells for 1-2 h had an opposite effect. In contrast to MT, invasion of tissue culture trypomastigotes (TCT) increased upon host cell pre-starvation or treatment with rapamycin, a novel finding that discloses quite distinctive features of the two infective forms in a key process for infection. 相似文献