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1.
Plant Biol (Stuttg) ; 24(2): 240-248, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34741381

ABSTRACT

Approximately 20,000 species of flowering plant offer mainly pollen to their pollinators, generally bees. Stamen dimorphism, a floral trait commonly present in some pollen flowers, is thought to be associated with exclusive pollen provision for highly effective bee pollinators. Notwithstanding, little is known about how stamen dimorphism is related to other floral morphological traits and, consequently, plant-pollinator interactions at the community scale. Here we investigated the relationship between stamen dimorphism and other floral morphological traits, as well as the interactions with pollinators in plants of Melastomataceae. We characterized each plant species as stamen dimorphic or stamen isomorphic according to differences in size and shape between stamen sets. Data on interactions between the plants and their bee pollinators were analysed as quantitative bipartite networks. We found that petal and style size and shape were correlated to stamen dimorphism. Stamen dimorphic species present larger flowers and less variable style shapes than stamen isomorphic species. Furthermore, stamen dimorphism is associated with higher richness of visiting bees, i.e. higher ecological generalization. During the evolutionary history of Melastomataceae, the dependence on pollinators for fruit set has possibly favoured the evolution of larger flowers with dimorphic stamens, which in turn are able to make use of a larger spectrum of pollen-collecting bees, leading to ecological generalization.


Subject(s)
Flowers/anatomy & histology , Melastomataceae , Pollination , Animals , Bees , Pollen
2.
Braz J Med Biol Res ; 52(8): e8711, 2019.
Article in English | MEDLINE | ID: mdl-31389494

ABSTRACT

Carotid artery assessment by ultrasound is a non-invasive evaluation of subclinical atherosclerosis and a predictor of cardiovascular events. However, ultrasound examinations are operator-dependent. In the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), ultrasound images have been acquired from more than 10,000 participants. In this article, we describe the reproducibility of carotid intima-media thickness (CIMT), carotid plaque detection, and carotid plaque score (defined as the number of arterial sites with plaques) using ELSA-Brasil protocol, in a subset of 118 participants. Two board-certified radiologists and a trained technician read carotid images. We calculated intra- and inter-observer intraclass correlation (ICC) for CIMT values. We also present kappa coefficients for plaque detection and weighted kappa coefficients for carotid plaque score. Participants were aged 58.2±6.6 years, and 60 (50.8%) were men. For common carotid artery CIMT measurements, intra- and inter-observer ICC values were very good to excellent, ranging from 0.90 (95% confidence interval [95%CI]: 0.72-0.95) to 0.98 (95%CI: 0.97-0.99). For carotid plaque, intra- (0.96 [95%CI: 0.96-0.96]) and inter- (0.99 [95%CI: 0.99-0.99]) observer weighted kappa coefficients were very good. Intra- and inter-observer Kappa coefficients for the presence of plaques by site were good to very good, ranging from 0.69 to 1.00. In conclusion, we found very good reproducibility for carotid plaque score and CIMT measurements in the ELSA-Brasil at baseline. These results are comparable to the best findings from similar large cohorts that analyzed carotid ultrasound data.


Subject(s)
Atherosclerosis/diagnostic imaging , Carotid Arteries/diagnostic imaging , Carotid Intima-Media Thickness , Plaque, Atherosclerotic/diagnostic imaging , Adult , Aged , Female , Humans , Longitudinal Studies , Male , Middle Aged , Observer Variation , Prospective Studies , Reproducibility of Results , Ultrasonography
3.
Braz. j. med. biol. res ; 52(8): e8711, 2019. tab
Article in English | LILACS | ID: biblio-1011600

ABSTRACT

Carotid artery assessment by ultrasound is a non-invasive evaluation of subclinical atherosclerosis and a predictor of cardiovascular events. However, ultrasound examinations are operator-dependent. In the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), ultrasound images have been acquired from more than 10,000 participants. In this article, we describe the reproducibility of carotid intima-media thickness (CIMT), carotid plaque detection, and carotid plaque score (defined as the number of arterial sites with plaques) using ELSA-Brasil protocol, in a subset of 118 participants. Two board-certified radiologists and a trained technician read carotid images. We calculated intra- and inter-observer intraclass correlation (ICC) for CIMT values. We also present kappa coefficients for plaque detection and weighted kappa coefficients for carotid plaque score. Participants were aged 58.2±6.6 years, and 60 (50.8%) were men. For common carotid artery CIMT measurements, intra- and inter-observer ICC values were very good to excellent, ranging from 0.90 (95% confidence interval [95%CI]: 0.72-0.95) to 0.98 (95%CI: 0.97-0.99). For carotid plaque, intra- (0.96 [95%CI: 0.96-0.96]) and inter- (0.99 [95%CI: 0.99-0.99]) observer weighted kappa coefficients were very good. Intra- and inter-observer Kappa coefficients for the presence of plaques by site were good to very good, ranging from 0.69 to 1.00. In conclusion, we found very good reproducibility for carotid plaque score and CIMT measurements in the ELSA-Brasil at baseline. These results are comparable to the best findings from similar large cohorts that analyzed carotid ultrasound data.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Carotid Arteries/diagnostic imaging , Atherosclerosis/diagnostic imaging , Plaque, Atherosclerotic/diagnostic imaging , Carotid Intima-Media Thickness , Observer Variation , Prospective Studies , Reproducibility of Results , Longitudinal Studies , Ultrasonography
4.
Redox Biol ; 12: 600-609, 2017 08.
Article in English | MEDLINE | ID: mdl-28391181

ABSTRACT

Ohr and OsmC proteins comprise two subfamilies within a large group of proteins that display Cys-based, thiol dependent peroxidase activity. These proteins were previously thought to be restricted to prokaryotes, but we show here, using iterated sequence searches, that Ohr/OsmC homologs are also present in 217 species of eukaryotes with a massive presence in Fungi (186 species). Many of these eukaryotic Ohr proteins possess an N-terminal extension that is predicted to target them to mitochondria. We obtained recombinant proteins for four eukaryotic members of the Ohr/OsmC family and three of them displayed lipoyl peroxidase activity. Further functional and biochemical characterization of the Ohr homologs from the ascomycete fungus Mycosphaerella fijiensis Mf_1 (MfOhr), the causative agent of Black Sigatoka disease in banana plants, was pursued. Similarly to what has been observed for the bacterial proteins, we found that: (i) the peroxidase activity of MfOhr was supported by DTT or dihydrolipoamide (dithiols), but not by ß-mercaptoethanol or GSH (monothiols), even in large excess; (ii) MfOhr displayed preference for organic hydroperoxides (CuOOH and tBOOH) over hydrogen peroxide; (iii) MfOhr presented extraordinary reactivity towards linoleic acid hydroperoxides (k=3.18 (±2.13)×108M-1s-1). Both Cys87 and Cys154 were essential to the peroxidase activity, since single mutants for each Cys residue presented no activity and no formation of intramolecular disulfide bond upon treatment with hydroperoxides. The pKa value of the Cysp residue was determined as 5.7±0.1 by a monobromobimane alkylation method. Therefore, eukaryotic Ohr peroxidases share several biochemical features with prokaryotic orthologues and are preferentially located in mitochondria.


Subject(s)
Ascomycota/enzymology , Eukaryota/metabolism , Peroxidases/genetics , Peroxidases/metabolism , Amino Acid Sequence , Animals , Ascomycota/chemistry , Ascomycota/genetics , Cysteine/genetics , Eukaryota/genetics , Evolution, Molecular , Fungal Proteins/chemistry , Fungal Proteins/genetics , Fungal Proteins/metabolism , Multigene Family , Musa/microbiology , Peroxidases/chemistry , Phylogeny , Sequence Homology, Amino Acid
5.
Physiol Res ; 65(Suppl 5): S633-S642, 2016 12 22.
Article in English | MEDLINE | ID: mdl-28006945

ABSTRACT

The present study evaluated the impact of neonatal administration of capsaicin (neurotoxin from red hot pepper used for sensory denervation) on postnatal development of the heart rate and ventricular contractility. In the rats subjected to capsaicin administration (100 mg/kg) on postnatal days 2 and 3 and their vehicle-treated controls at the ages of 10 to 90 days, function of the sympathetic innervation of the developing heart was characterized by evaluation of chronotropic responses to metipranolol and atropine, norepinephrine concentrations in the heart, and norepinephrine release from the heart atria. Sensory denervation was verified by determination of calcitonin gene-related peptide levels in the heart. Direct cytotoxic effects of capsaicin were assessed on cultured neonatal cardiomyocytes. Capsaicin-treated rats displayed higher resting heart rates, lower atropine effect, but no difference in the effect of metipranolol. Norepinephrine tissue levels and release did not differ from controls. Contraction force of the right ventricular papillary muscle was lower till the age of 60 days. Significantly reduced viability of neonatal cardiomyocytes was demonstrated at capsaicin concentration 100 micromol/l. Our study suggests that neonatal capsaicin treatment leads to impaired maturation of the developing cardiomyocytes. This effect cannot be attributed exclusively to sensory denervation of the rat heart since capsaicin acts also directly on the cardiac cells.


Subject(s)
Capsaicin/toxicity , Heart Rate/drug effects , Myocardial Contraction/drug effects , Myocytes, Cardiac/drug effects , Animals , Animals, Newborn , Cell Survival/drug effects , Cell Survival/physiology , Cells, Cultured , Female , Heart/drug effects , Heart/growth & development , Heart Rate/physiology , Male , Myocardial Contraction/physiology , Myocytes, Cardiac/physiology , Rats , Rats, Wistar
6.
Article in English | MEDLINE | ID: mdl-25999092

ABSTRACT

The increasing prevalence of antimicrobial resistances is now a worldwide problem. Investigating the mechanisms by which pets harboring resistant strains may receive and/or transfer resistance determinants is essential to better understanding how owners and pets can interact safely. Here, we characterized the genetic determinants conferring resistance to ß-lactams and quinolones in 38 multidrug-resistant Escherichia coli isolated from fecal samples of dogs, through PCR and sequencing. The most frequent genotype included the ß-lactamase groups TEM (n=5), and both TEM+CTX-M-1 (n=5). Within the CTX-M group, we identified the genes CTX-M-32, CTX-M-1, CTX-M-15, CTX-M-55/79, CTX-M-14 and CTX-M-2/44. Thirty isolates resistant to ciprofloxacin presented two mutations in the gyrA gene and one or two mutations in the parC gene. A mutation in gyrA (reported here for the first time), due to a transversion and transition (TCG→GTG) originating a substitution of a serine by a valine in position 83 was also detected. The plasmid-encoded quinolone resistance gene, qnrs1, was detected in three isolates. Dogs can be a reservoir of genetic determinants conferring antimicrobial resistance and thus may play an important role in the spread of antimicrobial resistance to humans and other co-habitant animals.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli Infections/veterinary , Escherichia coli/drug effects , Escherichia coli/enzymology , Feces/microbiology , beta-Lactamases/genetics , Animals , Ciprofloxacin/pharmacology , DNA Topoisomerase IV/genetics , Dogs , Electrophoresis, Gel, Pulsed-Field , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/genetics , Escherichia coli Infections/transmission , Genotype , Microbial Sensitivity Tests , Mutation , Phylogeny , Quinolones , beta-Lactamases/biosynthesis
7.
Int Endod J ; 48(8): 814, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25652146

ABSTRACT

The following article from International Endodontic Journal, 'Micro-computed tomography evaluation of apical transportation and centring ability of Reciproc and WaveOne systems in severely curved root canals' by D. A. de Meireles, T. C. C. A. de Brito, A. A. F. Marques, A. D. B. Garrido, L. F. R. Garcia & E. C. Sponchiado Jr, published online on 5 February 2015 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor in Chief, Prof. Paul Dummer, and John Wiley & Sons Ltd. The retraction has been agreed due to the use of techniques for crucial measurements in canal shaping and a lack of clarity regarding the measuring methodology. The use of inadequate measuring methodologies makes the findings of the paper invalid.

8.
Rev Bras Estud Popul ; 5(1): 1-20, 1988.
Article in Portuguese | MEDLINE | ID: mdl-12342018

ABSTRACT

"This paper presents the results of...fieldwork research relating to three Indian societies in Brazil, through the use of the model for the comparative study of fertility proposed by Kingsley Davis and Judith Blake. The collected data show changes within these societies which favourably affected fertility. From this evidence many other questions concerning the social organization and its influence on fertility are discussed." (SUMMARY IN ENG)


Subject(s)
Cross-Cultural Comparison , Fertility , Indians, South American , Socioeconomic Factors , Americas , Brazil , Culture , Demography , Developed Countries , Developing Countries , Economics , Ethnicity , Latin America , Population , Population Characteristics , Population Dynamics , Research , South America
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