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1.
J Biomech ; 163: 111955, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38266533

RESUMO

Breast implants are widely used after breast cancer resection and must be changed regularly to avoid a rupture. To date, there are no quantitative criteria to help this decision. The mechanical evolution of the gels and membranes of the implants is still underinvestigated, although it can lead to early rupture. In this study, 35 breast explants having been implanted in patients for up to 17 years were characterized by ex vivo measurements of their mechanical properties. Using Acoustic Radiation Force Impulse (ARFI) ultrasound elastography, an imaging method for non-destructive mechanical characterization, an increase in the stiffness of the explants has been observed. This increase was correlated with the implantation duration, primarily after 8 years of implantation. With an increase of the shear modulus of up to a factor of nearly 3, the loss of flexibility of the implants is likely to lead to a significant increase of their risk of rupture. A complementary analysis of the gel from the explants by mass spectrometry imaging (MSI) and liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) confirms the presence of metabolites of cholesterol originating from the breast tissues, which most likely crossed the membrane of the implants and most likely degrades the gel. By observing the consequences of the physical-chemical mechanisms at work within patients, this study shows that ultrasound elastography could be used in vivoas a quantitative indicator of the risk of breast implant rupture and help diagnose their replacement.


Assuntos
Implantes de Mama , Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Técnicas de Imagem por Elasticidade/métodos , Implantes de Mama/efeitos adversos , Ultrassom
2.
Sci Adv ; 9(34): eade8984, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37624884

RESUMO

Specialized metabolite (SM) diversification is a core process to plants' adaptation to diverse ecological niches. Here, we implemented a computational mass spectrometry-based metabolomics approach to exploring SM diversification in tissues of 20 species covering Nicotiana phylogenetics sections. To markedly increase metabolite annotation, we created a large in silico fragmentation database, comprising >1 million structures, and scripts for connecting class prediction to consensus substructures. Together, the approach provides an unprecedented cartography of SM diversity and section-specific innovations in this genus. As a case study and in combination with nuclear magnetic resonance and mass spectrometry imaging, we explored the distribution of N-acylnornicotines, alkaloids predicted to be specific to Repandae allopolyploids, and revealed their prevalence in the genus, albeit at much lower magnitude, as well as a greater structural diversity than previously thought. Together, the data integration approaches provided here should act as a resource for future research in plant SM evolution.


Assuntos
Metabolômica , Nicotiana , Nicotiana/genética , Aclimatação , Consenso , Bases de Dados Factuais
3.
Front Oncol ; 13: 1154493, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213297

RESUMO

Almost all pharmaceutical products are approved on the basis of their effect in patients representing the "average" of the population studied in registrational trials, with most drug labels allowing, at most, for empirical dose reduction in the case of toxicity. In this perspective article we explore some of the evidence that supports the use of personalised dosing in cancer treatment and show how we have been able to build on existing models linking dose, exposure and toxicity to demonstrate how dose optimisation, including increasing the dose, has the potential to significantly improve efficacy outcomes. We also explore, through the lens of our own experience of developing a personalised dosing platform, some of the hurdles that stand in the way of implementing a personalised approach to dosing in real world settings. In particular, our experience is illustrated by the application of a dosing platform for docetaxel treatment in prostate cancer.

4.
Sci Rep ; 13(1): 186, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604491

RESUMO

Position within the social group has consequences on individual lifespans in diverse taxa. This is especially obvious in eusocial insects, where workers differ in both the tasks they perform and their aging rates. However, in eusocial wasps, bees and ants, the performed task usually depends strongly on age. As such, untangling the effects of social role and age on worker physiology is a key step towards understanding the coevolution of sociality and aging. We performed an experimental protocol that allowed a separate analysis of these two factors using four groups of black garden ant (Lasius niger) workers: young foragers, old foragers, young nest workers, and old nest workers. We highlighted age-related differences in the proteome and metabolome of workers that were primarily related to worker subcaste and only secondarily to age. The relative abundance of proteins and metabolites suggests an improved xenobiotic detoxification, and a fuel metabolism based more on lipid use than carbohydrate use in young ants, regardless of their social role. Regardless of age, proteins related to the digestive function were more abundant in nest workers than in foragers. Old foragers were mostly characterized by weak abundances of molecules with an antibiotic activity or involved in chemical communication. Finally, our results suggest that even in tiny insects, extended lifespan may require to mitigate cancer risks. This is consistent with results found in eusocial rodents and thus opens up the discussion of shared mechanisms among distant taxa and the influence of sociality on life history traits such as longevity.


Assuntos
Formigas , Abelhas , Animais , Formigas/fisiologia , Envelhecimento/fisiologia , Comportamento Social , Fenótipo , Meio Social , Comportamento Animal/fisiologia
5.
Phytomedicine ; 105: 154370, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35977457

RESUMO

BACKGROUND: Hypertension is a major cardiovascular risk factor that affects most countries including those of Africa. Although Carissa edulis Vahl, Diodia scandens Sw. and Cleome gynandra L. are traditionally used in Benin as antihypertensive treatments with some efficacy mentioned by the local population, their biological activity on the cardiovascular system remains poorly studied. AIM: The study investigated the vasoreactivity of the plants and assessed the underlying mechanisms using isolated arteries. STUDY DESIGN: Aqueous-ethanolic extracts of aerial parts of C. edulis, D. scandens and C. gynandra were prepared by maceration before being subjected to multi-step liquid-liquid fractionation with solvents of increasing polarity. The vasoreactivity of the extracts and fractions were assessed on isolated porcine coronary artery and rat aorta using organ chambers, the role of nitric oxide (NO) using NG-nitro-L-arginine (NO synthase inhibitor), prostanoids using indomethacin (cyclooxygenases inhibitor) and endothelium-dependent hyperpolarization using TRAM-34 plus UCL 1684 (inhibitors of calcium-dependent K+ channels), and the vascular uptake of polyphenols using Neu reagent. RESULTS: The aqueous-ethanolic crude extract of C. edulis (CECE) induced potent relaxations that were exclusively endothelium-dependent and more pronounced than those to D. scandens and C. gynandra. The n-butanolic fraction of C. edulis (CEBF) was more active than the cyclohexane, dichloromethane, and ethyl acetate fractions. The relaxation induced by CECE and CEBF were inhibited by NG-nitro-L-arginine and affected neither by TRAM-34 plus UCL 1684 nor by indomethacin. CEBF induced sustained endothelium-dependent relaxations for at least 60 min, and inhibited, in a concentration-dependent manner, contractions to KCl, CaCl2, U46619 and serotonin in rings with endothelium. Analysis of CEBF by LCHRMS indicated the presence of polyphenols, terpenes, and alkaloids. Exposure of coronary artery and aorta rings to CEBF caused the accumulation of polyphenols predominantly in the endothelium. CONCLUSION: C. edulis leaf extract induced pronounced endothelium-dependent relaxations and inhibited contractile responses by stimulating the endothelial formation of NO. LCHRMS analysis of the most active fraction, the butanolic fraction, revealed the presence of numerous compounds including polyphenols, terpenes, and alkaloids. The polyphenols of CEBF accumulated preferentially in the endothelium of the arterial wall. Thus, these observations support the folkloric use of C. edulis in hypertension.


Assuntos
Apocynaceae , Hipertensão , Plantas Medicinais , Animais , Arginina , Benin , Vasos Coronários , Endotélio Vascular , Indometacina , Óxido Nítrico , Polifenóis , Suínos , Terpenos , Vasodilatação
6.
Microbiol Spectr ; 9(2): e0069221, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34468196

RESUMO

Sulfur metabolism in fuel-biodesulfurizing bacteria and the underlying physiological adaptations are not understood, which has impeded the development of a commercially viable bioprocess for fuel desulfurization. To fill these knowledge gaps, we performed comparative proteomics and untargeted metabolomics in cultures of the biodesulfurization reference strain Rhodococcus qingshengii IGTS8 grown on either inorganic sulfate or the diesel-borne organosulfur compound dibenzothiophene as a sole sulfur source. Dibenzothiophene significantly altered the biosynthesis of many sulfur metabolism proteins and metabolites in a growth phase-dependent manner, which enabled us to reconstruct the first experimental model for sulfur metabolism in a fuel-biodesulfurizing bacterium. All key pathways related to assimilatory sulfur metabolism were represented in the sulfur proteome, including uptake of the sulfur sources, sulfur acquisition, and assimilatory sulfate reduction, in addition to biosynthesis of key sulfur-containing metabolites such as S-adenosylmethionine, coenzyme A, biotin, thiamin, molybdenum cofactor, mycothiol, and ergothioneine (low-molecular weight thiols). Fifty-two proteins exhibited significantly different abundance during at least one growth phase. Sixteen proteins were uniquely detected and 47 proteins were significantly more abundant in the dibenzothiophene culture during at least one growth phase. The sulfate-free dibenzothiophene-containing culture reacted to sulfate starvation by restricting sulfur assimilation, enforcing sulfur-sparing, and maintaining redox homeostasis. Biodesulfurization triggered alternative pathways for sulfur assimilation different from those operating in the inorganic sulfate culture. Sulfur metabolism reprogramming and metabolic switches in the dibenzothiophene culture were manifested in limiting sulfite reduction and biosynthesis of cysteine, while boosting the production of methionine via the cobalamin-independent pathway, as well as the biosynthesis of the redox buffers mycothiol and ergothioneine. The omics data underscore the key role of sulfur metabolism in shaping the biodesulfurization phenotype and highlight potential targets for improving the biodesulfurization catalytic activity via metabolic engineering. IMPORTANCE For many decades, research on biodesulfurization of fossil fuels was conducted amid a large gap in knowledge of sulfur metabolism and its regulation in fuel-biodesulfurizing bacteria, which has impeded the development of a commercially viable bioprocess. In addition, lack of understanding of biodesulfurization-associated metabolic and physiological adaptations prohibited the development of efficient biodesulfurizers. Our integrated omics-based findings reveal the assimilatory sulfur metabolism in the biodesulfurization reference strain Rhodococcus qingshengii IGTS8 and show how sulfur metabolism and oxidative stress response were remodeled and orchestrated to shape the biodesulfurization phenotype. Our findings not only explain the frequently encountered low catalytic activity of native fuel-biodesulfurizing bacteria but also uncover unprecedented potential targets in sulfur metabolism that could be exploited via metabolic engineering to boost the biodesulfurization catalytic activity, a prerequisite for commercial application.


Assuntos
Metabolômica , Proteômica , Rhodococcus/genética , Rhodococcus/metabolismo , Enxofre/metabolismo , Fenômenos Bioquímicos , Cisteína/biossíntese , Glicopeptídeos , Inositol , Família Multigênica , Tiofenos/metabolismo
7.
Environ Sci Technol ; 55(8): 4720-4728, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33761249

RESUMO

Current approaches are often limited to evaluating the contribution of pesticide dissipation processes in water-sediment systems as both degradation and phase transfer, that is, sorption-desorption, contribute to the apparent decrease of pesticide concentration. Here, the dissipation of widely used herbicides acetochlor and S-metolachlor was examined in laboratory by water-sediment microcosm experiments under oxic and anoxic conditions. Compound-specific isotope analysis (CSIA) emphasized insignificant carbon isotope fractionation in the sediment, indicating prevailing pesticide degradation in the water phase. Conceptual modeling accounting for phase transfer and biodegradation indicated that biodegradation may be underestimated when phase transfer is not included. Phase transfer does not affect carbon isotope fractionation for a wide spectrum of molecules and environmental conditions, underscoring the potential of pesticide CSIA as a robust approach to evaluate degradation in water-sediment systems. CSIA coupled with the identification of transformation products by high-resolution tandem mass spectrometry suggests the degradation of acetochlor and S-metolachlor to occur via nucleophilic substitution and the predominance of oxalinic acids as transformation products under both anoxic and oxic conditions. Altogether, combining the pesticide CSIA, the identification of transformation products, and the use of conceptual phase-transfer models improves the interpretation of pesticide dissipation in water-sediment systems.


Assuntos
Herbicidas , Praguicidas , Poluentes Químicos da Água , Biodegradação Ambiental , Isótopos de Carbono , Herbicidas/análise , Água , Poluentes Químicos da Água/análise
8.
Life Sci Space Res (Amst) ; 28: 57-65, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33612180

RESUMO

Synthetic biology has potential spaceflight applications yet few if any studies have attempted to translate Earth-based synthetic biology tools into spaceflight. An exogenously inducible biological circuit for protein production in Arabidopsis thaliana, pX7-AtPDSi (Guo et al. 2003), was flown to ISS and functionally investigated. Seedlings were grown in a custom built 1.25 U plant greenhouse. Images recorded during the experiment show that leaves of pX7-AtPDSi seedlings photobleached as designed while wild type Col-0 leaves did not, which reveals that the synthetic circuit led to protein production during spaceflight. Polymerase chain reaction analysis post-flight also confirms that the Cre/LoxP (recombination system) portions of the circuit were functional in spaceflight. The subcomponents of the biological circuit, estrogen-responsive transcription factor XVE, Cre/LoxP DNA recombination system, and RNAi post-transcriptional gene silencing system now have flight heritage and can be incorporated in future designs for space applications. To facilitate future plant studies in space, the full payload design and manufacturing files are made available.


Assuntos
Arabidopsis/metabolismo , Voo Espacial , Biologia Sintética/métodos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estradiol , Integrases , Folhas de Planta/genética , Folhas de Planta/efeitos da radiação , Plantas Geneticamente Modificadas , Interferência de RNA , RNA de Plantas , Receptores de Estrogênio/genética , Fatores de Transcrição
9.
J Minim Invasive Gynecol ; 28(7): 1397-1402, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33197611

RESUMO

STUDY OBJECTIVE: To compare the outcomes of hysteroscopic management in women with a severe or nonsevere symptomatic cesarean scar defect (residual myometrium ≤3-mm vs >3-mm, respectively). DESIGN: Retrospective cohort study. SETTING: Gynecology department of a teaching hospital. PATIENTS: Seventy-one women with an operative hysteroscopy for a symptomatic defect (49 with severe defects and 22 with nonsevere ones). INTERVENTIONS: Operative hysteroscopy for cesarean scar defect in women with a severe defect (residual myometrium ≤3-mm) and with nonsevere defect (residual myometrium >3-mm). MEASUREMENTS: The main objective was to compare success rates between the 2 groups. The secondary objectives were the comparisons of (1) the number of women who required more than 1 procedure, (2) the rate of complications, (3) the number of subsequent pregnancies, and (4) the evolution of residual myometrium thickness between the groups. MAIN RESULTS: The success rates were not significantly different between the groups (73.5% in the severe group and 63.6% in the nonsevere group [p = .40]). The number of women requiring more than 1 procedure was also similar, as were the rate of complications and the mean increase of myometrium thickness. The rate of subsequent pregnancies in women who were infertile was significantly higher in women with a severe defect (p = .04). CONCLUSION: The hysteroscopic approach seems to be a good way to manage cesarean scar defects even when the residual myometrium is thin. A prospective study is, however, necessary to confirm these findings.


Assuntos
Cicatriz , Histeroscopia , Cesárea/efeitos adversos , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz/cirurgia , Feminino , Humanos , Gravidez , Estudos Prospectivos , Estudos Retrospectivos
10.
Reprod Biomed Online ; 40(4): 518-524, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32179010

RESUMO

RESEARCH QUESTION: To compare stimulated cycle (STC) versus modified natural cycle (MNC) for endometrial preparation prior to frozen embryo transfer (FET) in terms of convenience and efficacy. DESIGN: Prospective, open-label, randomized controlled study including 119 patients aged 20-38 years, undergoing intra-conjugal IVF/intracytoplasmic sperm injection, having regular cycles, at least two day 2 or day 3 frozen embryos, for whom it was the first or second FET performed, randomized to either MNC (n = 59) or STC (n = 60). Monitoring consisted of ultrasound and hormonal measurements. The number of monitoring visits required was compared between the two groups. RESULTS: STC required a significantly lower number of monitoring visits compared with MNC (3.6 ± 0.9 versus 4.4 ± 1.1, respectively, P < 0.0001), a lower number of blood tests (2.7 ± 0.8 versus 3.5 ± 1.0, respectively, P < 0.0001) and of ultrasounds (1.2 ± 0.4 versus 1.5 ± 0.6, respectively, P = 0.0039). FET during 'non-opening' hours (22.6% versus 27.5%, respectively, P = 0.32) and cancellation rates (11.7% versus 11.9%, respectively, P = 0.97) were comparable between the STC and MNC groups. No difference concerning HCG-positive rates (34.0% versus 23.1%, respectively, P = 0.22) nor live birth rates (24.5% for STC versus 23.1% for MNC, respectively, P = 0.86) was observed. Quality of life as defined by the FertiQol score was not different (P > 0.05 for each item). CONCLUSION: Altogether, these findings can be used for everyday clinical practice to better inform patients when deciding on the protocol to use for FET. These results suggest that MNC is a good option for patients reluctant to have injections, but requires increased monitoring. STC may offer more flexibility for patients and IVF centres.


Assuntos
Criopreservação , Transferência Embrionária/métodos , Endométrio , Indução da Ovulação/métodos , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Adulto Jovem
11.
Lipids ; 50(8): 749-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25820807

RESUMO

Here we have examined the composition of free sterols and steryl esters of pollen from selected angiosperm species, as a first step towards a comprehensive analysis of sterol biogenesis in the male gametophyte. We detected four major sterol structural groups: cycloartenol derivatives bearing a 9ß,19-cyclopropyl group, sterols with a double bond at C-7(8), sterols with a double bond at C-5(6), and stanols. All these groups were unequally distributed among species. However, the distribution of sterols as free sterols or as steryl esters in pollen grains indicated that free sterols were mostly Δ(5)-sterols and that steryl esters were predominantly 9ß,19-cyclopropyl sterols. In order to link the sterol composition of a pollen grain at anthesis with the requirement for membrane lipid constituents of the pollen tube, we germinated pollen grains from Nicotiana tabacum, a model plant in reproductive biology. In the presence of radiolabelled mevalonic acid and in a time course series of measurements, we showed that cycloeucalenol was identified as the major neosynthesized sterol. Furthermore, the inhibition of cycloeucalenol neosynthesis by squalestatin was in full agreement with a de novo biogenesis and an apparent truncated pathway in the pollen tube.


Assuntos
Magnoliopsida/química , Pólen/química , Esteróis/análise , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Esteróis/metabolismo
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