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1.
PLoS One ; 18(3): e0282253, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36952430

RESUMO

The sex difference of the 2D:4D digit ratio (female > male)-a proposed marker for prenatal testosterone exposure-is well established. Studies suggest it already exists in utero and is of moderate effect size in adulthood. However, evidence for the claim that 2D:4D reflects prenatal androgen action is limited, and the sex difference may exhibit lability during childhood. In the present study, 244 mothers were recruited in the course of an amniocentesis examination (performed between gestational weeks 14 and 18). Prenatal testosterone (T) and estradiol (E) levels were determined from amniotic fluid for boys and girls. The majority (97.4%, n = 114) of available female T levels (n = 117) were found below the level of quantification. Therefore, only male amniotic fluid data (n = 117) could be included for the analysis of associations between amniotic sex hormones (T levels and T to E ratio (T/E)) and 2D:4D. The families were then invited to each of the five consecutive follow-ups (ages: 5, 9, 20, 40, and 70 months) where children's 2D:4D was measured for both hands. The alternative marker D[r-l] reflects the directional asymmetry of 2D:4D (right subtracted by left 2D:4D) and was subsequently calculated as an additional measure for prenatal T exposure. No significant correlations between amniotic T or the T/E ratio (measured between week 14 and 18 of gestation) with 2D:4D respectively D[r-l] were observed for any time point. There was a significant sex difference (females > males) and a significant age effect with moderate correlations of 2D:4D between time points. 2D:4D increased between 20 and 40 months and between 40 and 70 months of age. The findings raise questions regarding the applicability of 2D:4D as a marker for prenatal androgen action and are discussed in terms of the reliability of obtained digit ratio data as well as in terms of the developmental timing of amniocentesis.


Assuntos
Androgênios , Razão Digital , Gravidez , Humanos , Masculino , Feminino , Criança , Estudos Longitudinais , Reprodutibilidade dos Testes , Dedos/anatomia & histologia , Hormônios Esteroides Gonadais , Testosterona/análise , Caracteres Sexuais
2.
Int J Surg ; 76: 171-177, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32169572

RESUMO

BACKGROUND: This cohort study evaluated factors, which have been shown to be relevant for Health-Related Quality of Live (HRQL) after cardiac surgery and investigated the combinatory impact on HRQL. Additionally, the aim was to introduce a first attempt to developing a risk estimation model which could identify patients at risk for impaired HRQL. METHODS: For this single-centre cohort study, 6099 cardiac surgical patients (60% isolated coronary bypass surgery) filled in the Nottingham Health Profile (NHP) for the evaluation of HRQL six months after surgery and provided information regarding their medical and socio-demographic status. For the NHP scores the deviation to the matched normative data of a healthy sample was calculated. A robust linear regression examined factors that influence HRQL. As a next step, based on the regression model, a risk estimation model was developed which is a first attempt to classify patients into risk categories. RESULTS: Male gender, age below 60 or between 60 and 74 years, living alone, no occupation, bypass surgery, NYHA status II, III or IV and chest pain were identified as risk factors to determine impaired HRQL. The model explains 29.13% of the variance. Based on the risk estimation model 27.4% were classified as medium or high risk. CONCLUSIONS: For the first time a multilevel method was applied to evaluate HRQL after heart surgery showing that socio-demographic variables are important co-factors to dyspnea and chest pain. We take a first attempt in developing a new approach that should encourage further research in this field to frame a screening tool that may help identifying patients at risk in the future.


Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Qualidade de Vida , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Ponte de Artéria Coronária/efeitos adversos , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários
3.
Trends Mol Med ; 25(11): 941-954, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31300343

RESUMO

Inflammation, over-reacting innate immunity, and CD4+ T cell depletion are hallmarks of HIV-1 infection. Self-DNA is usually not considered in the context of HIV-1-associated inflammation, although self-DNA contributes to inflammation in diverse pathologies, including autoimmune diseases, cancer, multiorgan failure after trauma, and even virus infections. Cells undergoing HIV-1-associated pyroptotic bystander cell death release self-DNA and other damage-associated molecular patterns (DAMPs), including chaperones and histones. In complexes with such DAMPs or extracellular vesicles, self-DNA gains immunogenic potential and becomes accessible to intracellular DNA sensors. Therefore, we hypothesize that self-DNA can contribute to HIV-1-associated inflammation. Self-DNA might not only drive HIV-1-associated 'inflamm-ageing' but also provide new opportunities for 'shock and kill' strategies aimed at eliminating latent HIV-1.


Assuntos
Alarminas , DNA , Infecções por HIV , Inflamação/patologia , Piroptose/imunologia , Alarminas/imunologia , Alarminas/metabolismo , Doenças Autoimunes/patologia , DNA/imunologia , DNA/metabolismo , Vesículas Extracelulares/metabolismo , Infecções por HIV/imunologia , Infecções por HIV/patologia , HIV-1/imunologia , Inflamassomos/metabolismo
4.
Neurosci Lett ; 707: 134298, 2019 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-31175935

RESUMO

Sex differences in mental rotation, robust in adults, have recently been reported for infants' looking times although the pattern of results is not completely conclusive. In this context, organizational effects of gonadal steroids affecting the neural circuitry underlying spatial cognition could be (partly) responsible for the early sex difference. In the present study testosterone and estradiol levels measured in amniotic fluid via ultra performance liquid chromatography and tandem mass spectrometry were used to examine the role of prenatal sex hormones on infants' looking times during mental rotation. N = 208 six-month-old infants participated in an expectation of violation task with 3D cube figures. Mental rotation was defined as the difference in looking times for familiar versus mirrored cube figures whereas vigilance was defined as the sum of both looking times. Sex differences were absent for mental rotation as well as for vigilance. Most importantly, however, for boys mental rotation but not vigilance was correlated with prenatal testosterone but not with estradiol. For girls mental rotation but not vigilance was correlated with prenatal estradiol but not with testosterone although it has to be noted that the testosterone values for girls suffered from a floor effect. Only 5% of the within-sex variance was due to prenatal sex hormones indicating small effects. These findings extend our knowledge concerning organizational effects of prenatal sex hormones on the brain circuitry underlying spatial cognition.


Assuntos
Líquido Amniótico/química , Estradiol/análise , Imaginação , Testosterona/análise , Atenção , Feminino , Fixação Ocular , Humanos , Lactente , Masculino , Reconhecimento Psicológico , Rotação , Fatores Sexuais
5.
J Chem Ecol ; 40(5): 458-67, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24809533

RESUMO

The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens.


Assuntos
Herbivoria , Insetos/fisiologia , Polifenóis/metabolismo , Quercus/fisiologia , Taninos/metabolismo , Animais , Interações Hospedeiro-Parasita , Folhas de Planta/química , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Polifenóis/análise , Quercus/química , Quercus/parasitologia , Taninos/análise
6.
Plant Physiol ; 152(3): 1705-15, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20023149

RESUMO

Nectars are rich in primary metabolites and attract mutualistic animals, which serve as pollinators or as an indirect defense against herbivores. Their chemical composition makes nectars prone to microbial infestation. As protective strategy, floral nectar of ornamental tobacco (Nicotiana langsdorffii x Nicotiana sanderae) contains "nectarins," proteins producing reactive oxygen species such as hydrogen peroxide. By contrast, pathogenesis-related (PR) proteins were detected in Acacia extrafloral nectar (EFN), which is secreted in the context of defensive ant-plant mutualisms. We investigated whether these PR proteins protect EFN from phytopathogens. Five sympatric species (Acacia cornigera, A. hindsii, A. collinsii, A. farnesiana, and Prosopis juliflora) were compared that differ in their ant-plant mutualism. EFN of myrmecophytes, which are obligate ant-plants that secrete EFN constitutively to nourish specialized ant inhabitants, significantly inhibited the growth of four out of six tested phytopathogenic microorganisms. By contrast, EFN of nonmyrmecophytes, which is secreted only transiently in response to herbivory, did not exhibit a detectable inhibitory activity. Combining two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with nanoflow liquid chromatography-tandem mass spectrometry analysis confirmed that PR proteins represented over 90% of all proteins in myrmecophyte EFN. The inhibition of microbial growth was exerted by the protein fraction, but not the small metabolites of this EFN, and disappeared when nectar was heated. In-gel assays demonstrated the activity of acidic and basic chitinases in all EFNs, whereas glucanases were detected only in EFN of myrmecophytes. Our results demonstrate that PR proteins causally underlie the protection of Acacia EFN from microorganisms and that acidic and basic glucanases likely represent the most important prerequisite in this defensive function.


Assuntos
Acacia/enzimologia , Quitinases/química , Glicosídeo Hidrolases/química , Néctar de Plantas/química , Proteínas de Plantas/química , Acacia/química , Acacia/microbiologia , Animais , Anti-Infecciosos/farmacologia , Formigas/fisiologia , Quitinases/isolamento & purificação , Glicosídeo Hidrolases/isolamento & purificação , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Doenças das Plantas/microbiologia , Proteínas de Plantas/isolamento & purificação , Especificidade da Espécie
7.
J Am Soc Mass Spectrom ; 14(11): 1282-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14597118

RESUMO

The activation energy for the unimolecular dissociation of a non-covalent supramolecular complex between an Artificial Cationic Receptor A ([Gua-Val-Val-Val-Amide]+, in which Gua is guanidiniocarbonyl pyrrole) and an Anionic Tetrapeptide B ([N-Acetyl-Val-Val-Ile-Ala]-) has been determined by measurement of the dissociation rate constant as a function of infrared CO2 laser power density. Singly-charged quasimolecular [A + B + H]+ ions are isolated, stored in a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer, and irradiated by IR photons. The rate constant for dissociation of the non-covalent complex is determined at five different laser power densities. A plot of the natural logarithm of the first-order rate constant versus the natural logarithm of the laser power density yields a straight line, the slope of which provides an approximate measure of the activation energy (Ea(laser)) for dissociation. Ea(laser) is calculated by a relationship derived earlier by Dunbar and with a newly proposed equation by Paech et al. The results of the two approaches deliver significantly different activation energy values for the unimolecular dissociation of the non-covalent complex. We obtain EaI(laser) = 0.67 eV (Dunbar approximation) and EaII(laser) = 1.12 eV (Paech et al. approximation). Differences between the two approaches are discussed with respect to non-covalent complexes.


Assuntos
Espectrometria de Massas/métodos , Oligopeptídeos/química , Bradicinina/química , Ciclotrons , Encefalinas/química , Análise de Fourier , Indicadores e Reagentes , Raios Infravermelhos , Leucina/química , Oligopeptídeos/síntese química , Receptores de Peptídeos/química
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