Publications by authors named "Yara Maria Rauh Muller"

Nowadays, changes in human lifestyle have increased dyslipidemia, reinforcing the necessity of using lipid-lowering drugs, such as statins, to control the lipid profile. Among the statins, rosuvastatin has shown greater efficacy in controlling dyslipidemia. Previous studies have shown adverse effects in adult men and pre-pubertal rodents after exposure to statins, such as reduced testosterone levels and delayed puberty.

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The toxicity of methylmercury (MeHg) during embryonic development is a relevant issue that remains unclear and deserves investigation. In this sense, there is evidence that links the intake of contaminated food with cardiovascular pathologies in human adults and children. Thus, this study aimed to verify the impact of MeHg on the structure and integrity of extraembryonic and cardiac blood vessels and the contractile function of cardiomyocytes, also evaluating embryonic weight and the cardiosomatic index (CSI).

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Glyphosate-based herbicides are widely used in global agriculture, and their effects on different non-target animal organisms have been the focus of many toxicological studies. Regarding the potential role of glyphosate-based herbicides as an endocrine disruptor, the present study aims to investigate the effects of the herbicide Roundup WG® (RWG) on female reproduction, specifically on the ovarian maturation of Danio rerio. Adult females were exposed to low concentrations of RWG (0.

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The endocrine system of crustaceans regulates the molt cycle with ecdysteroid hormones, mainly the 20-hydroxyecdysone (20-HE). Moreover, the molt process requires the action of chitinolytic enzymes (e.g.

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The hepatopancreas is the digestive organ of crustaceans, and plays important roles also in the synthesis and secretion of sexual hormones, immunological defenses and xenobiotic detoxification. Although the importance of this organ in crustaceans cannot be underestimated, the effects of ultraviolet B (UVB) radiation on hepatopancreas are poorly understood. Moreover, Macrobrachium prawns, have a transparent carapace, which make them more susceptible to UVB radiation, since their internal organs, such as hepatopancreas, are easily reached by solar radiation.

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The extracellular matrix (ECM) is a non-cellular and three-dimensional structure, constituted by a macromolecular dynamic network that involves the cells in all animal tissues, including embryonic ones. Several studies with vertebrates and cell cultures have reported deleterious effects of ultraviolet-B (UVB) radiation on the components associated with the ECM. However, studies focusing on the UVB radiation effects on ECM components of crustaceans during embryonic development are very scarce.

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Glyphosate-based herbicides (GBH), including Roundup®, are the most used herbicides in agricultural and non-agricultural areas, which can reach aquatic environments through drift during application or surface runoff. Some studies, mostly in fish, demonstrated that GBH caused oxidative stress in non-target animals. However, only few information is available on the GBH effects in the antioxidant and stress proteins of many other organisms, such as freshwater crustaceans.

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Glyphosate-based herbicides (GBH) are the most used herbicides worldwide and are considered as endocrine-disrupting compounds (EDC) for non-target organisms. However, effects of GBH on their endocrine systems remain poorly understood. Thus, the aim of this study was to assess the effects of low concentrations of Roundup WG® on growth and reproduction process molecules in both males and females of the decapod crustacean Macrobrachium potiuna, by the relative transcript expression levels of the ecdysteroid receptor (EcR), the molt-inhibiting hormone (MIH), and the vitellogenin (Vg) genes.

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Studies that investigate the cellular effects of homocysteine (Hcy) on the differentiation of neural cells, and their involvement in establishment of cell layers in the developing brain are scarce. This study evaluated how Hcy affects the neural cell cycle and proteins involved in neuronal differentiation in the telencephalon and mesencephalon using the chicken embryo as a model. Embryos at embryonic day 2 (E2) received 20 μmol D-L Hcy/50 μl saline and analyzed at E6.

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Glyphosate-based herbicides (GBH), including Roundup, are the most widely used pesticides in the world. Glyphosate residues have been detected in surface and groundwater, in food, and in human blood and urine. The effects of this herbicide on different levels of biological organization are an important concern that needs to be investigated.

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Article Synopsis
  • Developmental endochondral ossification relies on a steady blood supply from the embryonic vascular network, which can be disrupted by high levels of homocysteine (Hcy).
  • In a study on chicken embryos, treatment with Hcy led to significant decreases in important vasculogenic factors (VEGF, VCAM-1, NOS3) and osteocalcin, indicating Hcy's detrimental effects on blood vessel formation and bone mineralization.
  • Despite no observable differences in limb ossification area between Hcy-treated and untreated embryos, the findings highlight Hcy's toxicity by reducing critical proteins necessary for proper limb development during embryogenesis.
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Maternal hyperhomocysteinemia during pregnancy is associated with increased risk of NTD in the offspring. Our study investigated the effects of homocysteine (Hcy) on proliferation and neuronal differentiation of the spinal cord cells in a chick embryo model. Embryos were treated with 20μmol D-L Hcy/50μL saline solution at embryonic day 2 (E2) and analyzed at embryonic days 4 (E4) and 6 (E6).

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The crustaceans are one of the largest, most diverse, and most successful groups of invertebrates. The diversity among the crustaceans is also reflected in embryonic development models. However, the molecular genetics that regulates embryonic development is not known in those crustaceans that have a short germ-band development with superficial cleavage, such as Macrobrachium olfersi.

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High levels of ultraviolet-B (UVB) radiation can negatively affect aquatic animals. Macrobrachium olfersi is a prawn that lives in clear freshwaters and during the breeding season, females carry eggs in an external brood pouch. Therefore, we hypothesize that eggs are also exposed to environmental UVB radiation.

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High levels of homocysteine (Hcy) are related to an increased risk of the occurrence of congenital anomalies, including limb defects. However, few evaluations about how toxic levels of Hcy affect limb development have been reported. We investigated whether Hcy can affect the cell cycle proteins and proteins involved in mesenchymal cell differentiation during limb development, in a chicken embryo model.

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Interest in organoselenide chemistry and biochemistry has increased in the past three decades, mainly due to their chemical and biological activities. Here, we investigated the protective effect of the organic selenium compound diphenyl diselenide (PhSe)2 (5 μmol/kg), in a mouse model of methylmercury (MeHg)-induced brain toxicity. Our group has previously demonstrated that the oral and repeated administration (21 days) of MeHg (40 mg/L) induced MeHg brain accumulation at toxic concentrations, and a pattern of severe cortical and cerebellar biochemical and behavioral.

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Background: Neural tube defects (NTD) involve disruptions in the axial mesenchyme, and are related to an imbalance between folic acid (FA) and homocysteine (Hcy). This study evaluated the effects of FA/Hcy imbalance on cell proliferation and expression of the Pax 1/9 and Sox 9 gene products in the axial mesenchyme of chickens.

Methods: Embryos were incubated (38°C) and pretreated at 24 h and treated at 46 h of incubation.

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Lead is an important heavy metal pollutant in the environment, and it induces neurodevelopmental toxicity, which is characterized by histological, ultrastructural, and neurochemical changes in the central nervous system. The aim of this study was to evaluate the effects of prenatal acute lead exposure on apoptosis, GFAP expression, and lead deposition in the developing spinal cord. Chick embryos were exposed to 150μg or 450μg doses of lead acetate via yolk sac at E3 or E5 embryonic ages and incubated for six days.

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The simple organoselenium compound diphenyl diselenide (PhSe)(2) is a promising new pharmacological agent. However, few toxicological evaluations of this molecule have been reported. We evaluated the effects of acute administration of (PhSe)(2) on toxicological parameters in rabbits.

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Selenium can counteract methylmercury (MeHg) neurotoxicity. However, data about the neuroprotective effects of sodium selenite (Na(2)SeO(3)) on the activity of mitochondrial complexes and creatine kinase (mtCK) are scarce. Therefore, this study investigated the effects of the chronic exposure to Na(2)SeO(3) on brain energy metabolism and oxidative stress parameters in MeHg-poisoned mice.

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The recent decrease of the stratospheric ozone has resulted in an increase of ultraviolet-B (UV-B) radiation reaching the Earth's surface. In freshwater ecosystems with transparent water, UV-B rays easily penetrate and potentially cause harmful effects to organisms. In this study, embryos of the prawn Macrobrachium olfersi were used to evaluate the impact of UV-B rays in freshwater environments.

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Maternal ingestion of folic acid (FA) reduces neural tube defects, which are associated with high homocysteine levels. Present study evaluated the effects of FA and homocysteine on cell proliferation and cell adhesion, as well as on apoptosis, throughout the development of the spinal cord and mesenchyme of chicken embryos. Normal closure of the neural tube and a regular distribution of the mesenchymal cells were observed in control and FA-treated embryos.

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Studies on the crustacean nervous system have been responsible for advances in neuroscience and continue to play an important role in comparative neurobiology. The organization of crustacean brains provides clues about their phylogeny and might also offer some hints regarding their lifestyles. In this study, we compared the organization of specific brain regions of three species of marine shrimp with two species of freshwater prawns, making possible the identification of a pathway issuing from the periphery and cluster 9, which was not previously identified in freshwater prawns and shrimp.

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