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131.
Girardi LG Morshc M Oliveria AE Cechinel-Filho V Rodrigues CA 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(5-6):408-410
This paper shows the influence of benzenic groups on the chitosan surface for the separation of bioactive biflavonoids from Rheedia gardneriana leaves The yield of the biflavonoids using chitin modified with benzaldehyde (CH-Bz) as adsorbent in column chromatography was higher than that achieved with silica gel and chitosan. The presence of benzenic groups decreases the polarity of chitosan and consequently the interaction of hydrogen bonding between phenolic hydroxyl (OH) of biflavonoids and amine groups of the adsorbent. Therefore, the separation of these compounds appears to be the result of hydrophobicity and pi-pi interaction among electrons from the aromatic ring in sorbent and biflavonoid molecules. 相似文献
132.
E Girardi L Ravà P Pezzotti V Puro G Ippolito 《Journal of biological regulators and homeostatic agents》2001,15(3):229-234
The objective of this study was to develop and validate a method for estimating and monitoring over time the transmission rate of vertically acquired HIV infection at the population level. We estimated the annual number of children born to HIV-infected women in Italy in 1991-1994 by multiplying the seroprevalence rates, provided by Anonymous Unlinked HIV Serosurveys among Italian Newborns, by the annual number of births, provided by the Italian National Institute of Statistics. The number of HIV-infected children was estimated by applying a simplified back-calculation method to the incident cases of vertically acquired AIDS reported to the AIDS surveillance registry, using seven different estimates of the distribution of the incubation period identified through a literature search. The annual vertical transmission rates were estimated by dividing the estimated number of children with vertically acquired HIV infection by the estimated number of births to an HIV-infected mother. Depending on the chosen distribution of the incubation period, the estimated transmission rate for the four-year period ranges from 0.10 to 0.30. Five of the seven incubation distributions provided a rate falling within the very narrow interval 0.18-0.20. The method provided estimates of vertical transmission rates consistent with those of longitudinal studies performed in European countries. The method presented here could be useful for monitoring the impact of interventions aimed at reducing HIV vertical transmission rate. 相似文献
133.
Gaya Lde G Mourão GB de Rezende FM de Mattos EC Michelan Filho T Figueiredo LG Ferraz JB Eler JP 《Genetics and molecular research : GMR》2005,4(4):760-764
Data of chickens from a broiler-breeding program were collected and used to determine the genetic trends of absolute and relative abdominal fat content. The genetic trends were estimated by the regression of trait genetic value averages on hatch-years. Genetic values from 32,485 individuals were used for regression analysis. The genetic trend estimate for absolute abdominal fat content was +0.39 g per year, indicating that abdominal fat deposition in the analyzed line, in absolute terms, tended to increase, making the existing excess fat deposition in the broilers even worse. However, the genetic trend of relative abdominal fat content was not significant, indicating that there is no increase on abdominal fat content when it is corrected for body weight. 相似文献
134.
Role of dipeptidyl peptidase IV in regulating activity of Na+/H+ exchanger isoform NHE3 in proximal tubule cells 总被引:1,自引:0,他引:1
Girardi AC Knauf F Demuth HU Aronson PS 《American journal of physiology. Cell physiology》2004,287(5):C1238-C1245
We recently reported that NHE3 exists in multimeric complexes with dipeptidyl peptidase IV (DPPIV) in renal brush-border membranes. To examine the possible role of DPPIV in modulating NHE3 activity, we evaluated whether specific competitive inhibitors that bind to the active site of DPPIV affect NHE3 activity in the OKP line of opossum kidney proximal tubule cells. The DPPIV inhibitors diprotin A and P32/98 significantly reduced NHE3 activity, whereas the inactive isomer P34/98 had no effect. DPPIV inhibitors did not reduce the activity of another brush-border transport process, Na-phosphate cotransport. Effects of DPPIV inhibitors on NHE3 activity were not associated with detectable changes in amount or apparent molecular weight of NHE3 or in NHE3 surface expression. To investigate the signaling mechanisms involved in modulation of NHE3 activity by DPPIV, we used inhibitors of protein kinase pathways known to regulate NHE3. Whereas the PKA inhibitor H-89 failed to block the effect of DPPIV inhibitors, the tyrosine kinase inhibitor genistein alone caused a decrement in NHE3 activity very similar in magnitude to that caused by P32/98. We also found that the effects of genistein and P32/98 on NHE3 activity were not additive. In contrast, forskolin/IBMX and P32/98 had additive inhibitory effects on NHE3 activity. These findings suggested that the effect of DPPIV inhibitors to reduce NHE3 activity results from inhibition of a tyrosine kinase signaling pathway rather than by activation of PKA. We conclude that DPPIV plays an unexpected role in modulating Na+/H+ exchange mediated by NHE3 in proximal tubule cells. sodium/hydrogen exchange; diprotin A; P32/98; tyrosine kinase 相似文献
135.
Specific [3H]-MK801 binding to rat NMDA receptors following the administration of the convulsant drug 3-mercaptopropionic acid (MP) and the adenosine analogue cyclopentyladenosine (CPA) was studied in striatal membrane fractions. MP administration (150 mg/kg, i.p.) caused an increase of 53% and 82% in [3H]-MK801 binding during seizure and the postseizure period respectively. Administration of CPA (2 mg/kg, i.p.) raised [3H]-MK801 binding by 72%. When CPA was administered 30 min before MP and rats sacrificed at seizure (CPA + MPc), an increase of 64%, was observed. Saturation results indicate that receptor sites increased their maximal binding capacity (Bmax) in all treatments while the apparent dissociation constant (Kd) remained unchanged. MP administration brought about an increase of 52% and 42% in [3H]-MK801 binding sites during seizure and postseizure respectively. Administration of CPA raised receptor density by 75%. When CPA was administered 30 min before MP and rats sacrificed at seizure (CPA + MPc), an increase of 62%, was observed. These results show that striatal NMDA receptors have a selective role in seizure activity in the basal ganglia and that the adenosine analogue administration may modify [3H]-MK801 binding in a way similar to that of the convulsant drug. 相似文献
136.
137.
Mirko De Rosso Christine M. Mayr Giordano Girardi Antonio Dalla Vedova Riccardo Flamini 《Metabolomics : Official journal of the Metabolomic Society》2018,14(10):124
Introduction
Grape varieties allowed to produce Amarone della Valpolicella and Recioto DOCG wines are strictly regulated by their disciplinary of production. These are Corvina Veronese and Corvinone grapes, to a lesser extent also Rondinella can be used. The use of other varieties, is not allowed.Objectives
To identify chemical markers suitable to reveal addition of two not allowed grape varieties to the Corvina/Corvinone blend, such as Primitivo or Negro Amaro.Methods
The identification of the secondary metabolites of the four grape varieties was conducted by high-resolution mass spectrometry (HRMS) metabolomics. By using the signals of these metabolites the indexes able to identify the presence of Primitivo or Negro Amaro grapes in the Corvina/Corvinone 1:1 blend were calculated.Results
Indexes of laricitrin (Lr), delphinidin (Dp), and petunidin (Pt) signals were effective to identify the use of 10% Primitivo, while α-terpineol pentosyl-hexoside and linalool pentosyl-hexoside reveal the presence of Negro Amaro in the grape blend.Conclusions
Varietal markers useful to detect the presence of Primitivo and Negro Amaro in the grape blend were identified by HRMS metabolomics, a method suitable to check the identity of grapes on arrival at the winery, as well as the fermenting musts. The effectiveness of the identified markers in the final wines have to be confirmed. Potentially, a similar approach can be used to reveal analogous frauds performed on other high-quality wines.138.
Basil P Hubbard Christine Loh Ana P Gomes Jun Li Quinn Lu Taylor LG Doyle Jeremy S Disch Sean M Armour James L Ellis George P Vlasuk David A Sinclair 《Cell cycle (Georgetown, Tex.)》2013,12(14):2233-2240
SIRT1 is an NAD+-dependent deacetylase that counteracts multiple disease states associated with aging and may underlie some of the health benefits of calorie restriction. Understanding how SIRT1 is regulated in vivo could therefore lead to new strategies to treat age-related diseases. SIRT1 forms a stable complex with DBC1, an endogenous inhibitor. Little is known regarding the biochemical nature of SIRT1-DBC1 complex formation, how it is regulated and whether or not it is possible to block this interaction pharmacologically. In this study, we show that critical residues within the catalytic core of SIRT1 mediate binding to DBC1 via its N-terminal region, and that several carboxamide SIRT1 inhibitors, including EX-527, can completely block this interaction. We identify two acetylation sites on DBC1 that regulate its ability to bind SIRT1 and suppress its activity. Furthermore, we show that DBC1 itself is a substrate for SIRT1. Surprisingly, the effect of EX-527 on SIRT1-DBC1 binding is independent of DBC1 acetylation. Together, these data show that protein acetylation serves as an endogenous regulatory mechanism for SIRT1-DBC1 binding and illuminate a new path to developing small-molecule modulators of SIRT1. 相似文献
139.
ABSTRACTThe purpose of this study was to investigate whether childhood experiences with family pets are associated with symptoms of depression and anxiety in early adulthood. Undergraduate students (n=318) responded to an online survey that included questions about bonding with childhood pets, exposure to family violence and human aggression directed toward family pets in childhood, and current symptoms of depression and anxiety. Two-way ANCOVAs were conducted with a measure of childhood emotional abuse included as a covariate, and significant interactions were observed between pet bonding and exposure to aggression toward pets (pet aggression). Among participants with medium-level bonds, those who were exposed to pet aggression had significantly higher depression and anxiety scores than those who were not exposed to pet aggression. Among participants who were not exposed to pet aggression, those with medium-level bonds had lower depression and anxiety scores than those with low-level bonds. Bearing in mind the limitations of the research design, the results are consistent with the assertion that bonding with pets may support mental health and that exposure to animal cruelty may lead to the development of internalizing symptoms. The results also support the contention that both bonding with pets and exposure to pet aggression should be considered when investigating the association between experiences with pets and mental health. Interventions for the protection of children may be indicated in cases of animal cruelty. Social workers who investigate child maltreatment may be advised to refer children who are exposed to animal cruelty for counseling. Clinicians should consider addressing issues that arise from exposure to pet aggression during the therapeutic process. 相似文献