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1.
Gen Comp Endocrinol ; 357: 114598, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39122124

RESUMO

Environmental cues such as temperature induce macroscopic changes in the molting cycle of crustaceans, however, the physiological mechanisms behind these changes remain unclearWe aimed to investigate the regulatory mechanisms in the intermolt and premolt stages of the Callinectes sapidus molt cycle in response to thermal stimuli. The concentration of ecdysteroids and lipids in the hemolymph, and the expression of heat shock proteins (HSPs) and molt key genes were assessed at 19 °C, 24 °C and 29 °C. The premolt animals exhibited a much larger response to the colder temperature than intermolt animals. Ecdysteroids decreased drastically in premolt animals, whereas the expression of their hepatopancreas receptor (CasEcR) increased, possibly compensating for the low hemolymphatic levels at 19 °C. This decrease might be due to increased HSPs and inhibited ecdysteroidogenesis in the Y-organ. In addition, the molting-inhibiting hormone expression in the X-organ/sinus gland (XO/SG) remained constant between temperatures and stages, suggesting it is constitutive in this species. Lipid concentration in the hemolymph, and the expression of CasEcR and CasHSP90 in the XO/SG were influenced by the molting stage, not temperature. On the other hand, the expression of HSPs in the hepatopancreas is the result of the interaction between the two factors evaluated in the study. Our results demonstrated that temperature is an effective modulator of responses related to the molting cycle at the endocrine level and that temperature below the control condition caused a greater effect on the evaluated responses compared to the thermostable condition, especially when the animal was in the premolt stage.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37972916

RESUMO

Light is a strong stimulus for the sensory and endocrine systems. The opsins constitute a large family of proteins that can respond to specific light wavelengths. Hippocampus reidi is a near-threatened seahorse that has a diverse color pattern and sexual dimorphism. Over the years, H. reidi's unique characteristics, coupled with its high demand and over-exploitation for the aquarium trade, have raised concerns about its conservation, primarily due to their significant impact on wild populations. Here, we characterized chromatophore types in juvenile and adult H. reidi in captivity, and the effects of specific light wavelengths with the same irradiance (1.20 mW/cm2) on color change, growth, and survival rate. The xanthophores and melanophores were the major components of H. reidi pigmentation with differences in density and distribution between life stages and sexes. In the eye and skin of juveniles, the yellow (585 nm) wavelength induced a substantial increase in melanin levels compared to the individuals kept under white light (WL), blue (442 nm), or red (650 nm) wavelengths. In addition, blue and yellow wavelengths led to a higher juvenile mortality rate in comparison to the other treatments. Adult seahorses showed a rhythmic color change over 24 h, the highest reflectance values were obtained in the light phase, representing a daytime skin lightening for individuals under WL, blue and yellow wavelength, with changes in the acrophase. The yellow wavelength was more effective on juvenile seahorse pigmentation, while the blue wavelength exerted a stronger effect on the regulation of adult physiological color change. Dramatic changes in the opsin mRNA levels were life stage-dependent, which may infer ontogenetic opsin functions throughout seahorses' development. Exposure to specific wavelengths differentially affected the opsins mRNA levels in the skin and eyes of juveniles. In the juveniles, skin transcripts of visual (rh1, rh2, and lws) and non-visual opsins (opn3 and opn4x) were higher in individuals under yellow light. While in the juvenile's eyes, only rh1 and rh2 had increased transcripts influenced by yellow light; the lws and opn3 mRNA levels were higher in juveniles' eyes under WL. Prolonged exposure to yellow wavelength stimulates a robust increase in the antioxidant enzymes sod1 and sod2 mRNA levels. Our findings indicate that changes in the visible light spectrum alter physiological processes at different stages of life in H. reidi and may serve as the basis for a broader discussion about the implications of artificial light for aquatic species in captivity.


Assuntos
Opsinas , Smegmamorpha , Humanos , Animais , Opsinas/genética , Opsinas/metabolismo , Pigmentação da Pele , Smegmamorpha/genética , Smegmamorpha/metabolismo , Oxirredução , RNA Mensageiro/metabolismo
3.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806020

RESUMO

To investigate the role of the transient receptor potential channel vanilloid type 1 (TRPV1) in hepatic glucose metabolism, we analyzed genes related to the clock system and glucose/lipid metabolism and performed glycogen measurements at ZT8 and ZT20 in the liver of C57Bl/6J (WT) and Trpv1 KO mice. To identify molecular clues associated with metabolic changes, we performed proteomics analysis at ZT8. Liver from Trpv1 KO mice exhibited reduced Per1 expression and increased Pparα, Pparγ, Glut2, G6pc1 (G6pase), Pck1 (Pepck), Akt, and Gsk3b expression at ZT8. Liver from Trpv1 KO mice also showed reduced glycogen storage at ZT8 but not at ZT20 and significant proteomics changes consistent with enhanced glycogenolysis, as well as increased gluconeogenesis and inflammatory features. The network propagation approach evidenced that the TRPV1 channel is an intrinsic component of the glucagon signaling pathway, and its loss seems to be associated with increased gluconeogenesis through PKA signaling. In this sense, the differentially identified kinases and phosphatases in WT and Trpv1 KO liver proteomes show that the PP2A phosphatase complex and PKA may be major players in glycogenolysis in Trpv1 KO mice.


Assuntos
Gluconeogênese , Proteoma , Canais de Cátion TRPV , Animais , Expressão Gênica , Gluconeogênese/genética , Glucose/metabolismo , Glicogênio/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteoma/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
4.
Radiol Med ; 121(1): 12-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26210815

RESUMO

PURPOSE: To establish the appropriate number of Cardiac-CT and Cardio-MR examinations, to determine an economically justified and sustainable investment in these two technologies, for an exclusive cardiologic use. MATERIALS AND METHODS: From July 2013 to July 2014, through a survey in four different Italian Departments of Radiology, data on the costs of Cardiac-CT and Cardiac-MR examinations were collected. For the evaluation of the costs of examinations, it was used an analytical accounting system, considering only the direct costs (consumables, health personnel work time, equipment amortization/maintenance) and other costs (utilities, services, etc.). Indirect costs (general costs) were not assessed. It was made a simulation, assuming an exclusive use of the CT and MR equipments for Cardiac-CT and Cardiac-MR examinations, calculating the annual number necessary to arrive at the Break Even Point (BEP: the point at which cost or expenses and revenue are equal). RESULTS: On the basis of the CT costs, in order to reach the BEP, performing only Cardiac-CT examinations, an average of 2641-2752 examinations/year is needed. The annual time commitment of the Medical Professional to ensure the number of examinations to reach the BEP is 2625-2750 h/year, equivalent to two Medical Doctors in a Cardiology Department. The recent Cardiac-CT Italian Registry, in the period January-June 2011, reports a number of examinations of 3455 patients in 47 different Centers, distributed throughout the whole national territory. With regard to MR, in order to reach the BEP, performing only Cardiac-MR examinations, an average of 2435-3123 examinations/year is needed. The annual time commitment of the Medical Professional to ensure the number of examinations to reach the BEP is 2437-3125 h/year, equivalent to two Medical Doctors in a Cardiology Department. The recent Cardiac-MR Italian Registry reports a number of examinations of 3776 patients in 40 Centers, distributed throughout the whole national territory. CONCLUSION: This research has shown that, only on the basis of costs, currently in Italy is anti-economic an exclusive use of CT or MR equipment for cardiac exams, unless it's not decided, regardless of the recent guidelines and clinical indications, to submit all patients with cardiac diseases (diseases of the coronary arteries and cardiomyopathies) to Cardiac-CT and Cardiac-MR examinations. This might likely to increase both the inappropriate examinations and either health spending and in the case of CT with important repercussions, in terms of radio-exposure, subject to forensic procedures.


Assuntos
Doenças Cardiovasculares/diagnóstico , Custos e Análise de Custo , Imageamento por Ressonância Magnética/economia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Tomografia Computadorizada por Raios X/economia , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Doenças Cardiovasculares/diagnóstico por imagem , Humanos , Itália , Sistema de Registros , Inquéritos e Questionários
5.
J Photochem Photobiol B ; 242: 112702, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37018912

RESUMO

The presence of melanopsin (OPN4) has been shown in cultured murine melanocytes and was associated with ultraviolet A radiation (UVA) reception. Here we demonstrated the protective role of OPN4 in skin physiology and the increased UVA-induced damage in its absence. Histological analysis showed a thicker dermis and thinner hypodermal white adipose tissue layer in Opn4-/- (KO) mice than in wild-type (WT) animals. Proteomics analyses revealed molecular signatures associated with proteolysis, remodeling chromatin, DNA damage response (DDR), immune response, and oxidative stress coupled with antioxidant responses in the skin of Opn4 KO mice compared to WT. Skin protein variants were found in Opn4 KO mice and Opn2, Opn3, and Opn5 gene expressions were increased in the genotype. We investigated each genotype response to UVA stimulus (100 kJ/m2). We found an increase of Opn4 gene expression following stimulus on the skin of WT mice suggesting melanopsin as a UVA sensor. Proteomics findings suggest that UVA decreases DDR pathways associated with ROS accumulation and lipid peroxidation in the skin of Opn4 KO mice. Relative changes in methylation (H3-K79) and acetylation sites of histone between genotypes and differentially modulated by UVA stimulus were also observed. We also identified alterations of molecular traits of the central hypothalamus-pituitary- adrenal (HPA) and the skin HPA-like axes in the absence of OPN4. Higher skin corticosterone levels were detected in UVA-stimulated Opn4 KO compared to irradiated WT mice. Taken altogether, functional proteomics associated with gene expression experiments allowed a high-throughput evaluation that suggests an important protective role of OPN4 in regulating skin physiology in the presence and absence of UVA radiation.


Assuntos
Opsinas de Bastonetes , Pele , Animais , Camundongos , Homeostase , Melanócitos/metabolismo , Proteínas de Membrana/metabolismo , Opsinas de Bastonetes/genética , Opsinas de Bastonetes/metabolismo , Pele/metabolismo , Raios Ultravioleta/efeitos adversos
6.
Materials (Basel) ; 15(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35269104

RESUMO

This study proposed an evaluation of enrichment processes of obsolete Printed Circuit Boards (PCBs), by means of gravity and electrostatic separation, aiming at the recovery of metals. PCBs are the most important component in electronic devices, having high concentrations of metals and offering a secondary source of raw materials. Its recycling promotes the reduction in the environmental impacts associated with its production, use, and disposal. The recovery method studied started with the dismantling of the PCB, followed by a comminution and granulometric classification. Subsequent magnetic, gravity, and electrostatic separations were performed. After the separations, a macroscopic visual evaluation and chemical analysis were carried out, determining the metal content in the concentrate products. The results obtained from gravity separation showed a product with metallic concentrations of 89% and 76% for particle sizes of 0.3−0.6 mm and 0.6−1.18 mm, respectively. In electrostatic separation, the product obtained was 88% for the lower particle size (<0.3 mm) and 62% for particles sizes >1.18 mm.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33672661

RESUMO

Vinyl floors are widely used in public areas for their low cost and easy cleaning. From 1960 to 1980, asbestos was often added to improve vinyl floor performances. The Italian Ministerial Decree (M.D.) 06/09/94 indicates asbestos vinyl tiles as non-friable materials and, therefore, few dangerous to human health. This work aims to check through three different experimental tests if asbestos floor tiles, after decades of use, maintain their characteristics of compactness and non-friability. The effect of a small stone fragment stuck in the sole of rubber shoes was reproduced by striking the vinyl floor with a crampon. A vinyl tile was broken into smaller pieces with the aid of pliers to simulate what normally happens when workers replace the floors or sample it to verify the presence of asbestos. The third test reproduced the abrasion of the tile surface due to the dragging of furniture or heavy materials or sand grains that remain attached to the soles of shoes. The tests were carried out in safe conditions, working under an extractor hood with a glove box. Airborne sampling in the hood obtained the concentration of asbestos fibers produced in each test. The simulation tests performed confirms the possible release of fibers if the vinyl tiles are cut, abraded or perforated, as indicated by the Italian M.D.


Assuntos
Poluentes Ocupacionais do Ar , Amianto , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Amianto/análise , Pisos e Cobertura de Pisos , Humanos , Itália , Exposição Ocupacional/análise , Cloreto de Polivinila
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