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1.
Environ Entomol ; 52(6): 1057-1070, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37804089

RESUMO

Mechanisms, including autophagy and apoptosis, which serve to regulate and ensure proper organism functions under optimal conditions, play additional defensive roles under environmental pressure. The aim of this study was to test the following hypotheses: (i) elevated autophagy and apoptosis intensity levels, as defensive processes in response to contact with cadmium, are maintained for a limited number of generations and (ii) the number of generations after which levels of cell death processes reach the reference level depends on selective pressure. Cell death processes were assessed by light and transmission electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL), and cytometric analyses. Model insects (Spodoptera exiqua, Hübner, 1808) were orally exposed to various concentrations of cadmium for 18 generations and compared with reference strains exposed to cadmium or not (control) for over 150 generations. Elevated programmed cell death intensity levels decreased after several generations, indicating tolerance of individuals to cadmium in the diet and verifying the first hypothesis; however, testing the second hypothesis indicated that the number of generations depended not only on pressure intensity, but also on cell death type, since levels of autophagy remained increased for a minimum of 12 generations.


Assuntos
Cádmio , Mariposas , Animais , Spodoptera/fisiologia , Cádmio/toxicidade , Cádmio/metabolismo , Larva/metabolismo , Mariposas/metabolismo , Morte Celular
2.
Environ Toxicol Pharmacol ; 101: 104209, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37399851

RESUMO

Microplastic enlisted as a contaminant of emerging concerns in polluted environments interact with "traditional" contaminants such as metals, causing, among others, their increased accumulation in the body. Harmful effects depend on the exposed animals' possible preadaptation and/or cross-tolerance. The project aimed to assess the role of this phenomenon in the limited toxicity of polypropylene fibers (PPf) in 0%, 0.02%, 0.06, 0.18%, 0.54%, and 1.6% of Cd-supplemented food of larvae of Spodoptera exigua multigenerationally selected to cadmium tolerance. The activity of 20 digestive enzymes (API-ZYM test), defensins, and heat shock proteins, HSP70 levels in the exposed groups were used as biomarkers. PPfs caused the increase of Cd accumulation in the body, while intake of polypropylene microfibers did not change the biomarker levels. Moreover, multigenerational Cd pre-exposure, due to increased tolerance of Cd and, possibly, cross-tolerance, prepares the insects for an additional stressor (PPf) alone and in interaction with cadmium.


Assuntos
Cádmio , Polipropilenos , Animais , Cádmio/toxicidade , Cádmio/metabolismo , Polipropilenos/metabolismo , Plásticos , Proteínas de Choque Térmico , Spodoptera , Biomarcadores/metabolismo
3.
Sci Rep ; 11(1): 21147, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34707140

RESUMO

Tryptophan (TRP) is one of the essential amino acids in the animal body. Its exogenicity and low concentrations mean that it can be regarded as one of the key regulatory molecules at the cellular as well as physiological level. It has been shown to have a number of essential functions, such as in the production of other biologically active molecules. The main objective of this project was to investigate the effects of a high monosaccharide diet (HMD) on a hemimetabolic insect-house cricket (Acheta domesticus) and a mutant strain with impaired visual pigment synthesis (closely related to the tryptophan and kynurenine (KYN) metabolic pathway)-white eye. This study was aimed at determining the effects of glucose and fructose on cricket development and biochemical composition. A parallel goal was to compare the response of both cricket strains to HMD. ELISA assays indicated dysfunction of the TRP-KYN pathway in white strain insects and an elevated KYN/TRP ratio. Biochemical analyses demonstrated the effects of HMD mainly on fat and glycogen content. A decrease in food intake was also observed in the groups on HMD. However, no changes in imago body weight and water content were observed. The results of the study indicate a stronger response of the white strain to HMD compared to the wild-type strain. At the same time, a stronger detrimental effect of fructose than of glucose was apparent. Sex was found to be a modulating factor in the response to HMD.


Assuntos
Dieta , Gryllidae/metabolismo , Cinurenina/metabolismo , Monossacarídeos/metabolismo , Triptofano/metabolismo , Animais , Feminino , Glicogênio/metabolismo , Gryllidae/genética , Gryllidae/crescimento & desenvolvimento , Masculino , Mutação , Pigmentação/genética
4.
Sensors (Basel) ; 21(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34300544

RESUMO

Gamification is known to enhance users' participation in education and research projects that follow the citizen science paradigm. The Cosmic Ray Extremely Distributed Observatory (CREDO) experiment is designed for the large-scale study of various radiation forms that continuously reach the Earth from space, collectively known as cosmic rays. The CREDO Detector app relies on a network of involved users and is now working worldwide across phones and other CMOS sensor-equipped devices. To broaden the user base and activate current users, CREDO extensively uses the gamification solutions like the periodical Particle Hunters Competition. However, the adverse effect of gamification is that the number of artefacts, i.e., signals unrelated to cosmic ray detection or openly related to cheating, substantially increases. To tag the artefacts appearing in the CREDO database we propose the method based on machine learning. The approach involves training the Convolutional Neural Network (CNN) to recognise the morphological difference between signals and artefacts. As a result we obtain the CNN-based trigger which is able to mimic the signal vs. artefact assignments of human annotators as closely as possible. To enhance the method, the input image signal is adaptively thresholded and then transformed using Daubechies wavelets. In this exploratory study, we use wavelet transforms to amplify distinctive image features. As a result, we obtain a very good recognition ratio of almost 99% for both signal and artefacts. The proposed solution allows eliminating the manual supervision of the competition process.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Artefatos , Humanos , Aprendizado de Máquina , Análise de Ondaletas
5.
Sci Rep ; 10(1): 21141, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273657

RESUMO

Autophagy is a natural process that aims to eliminate malfunctioning cell parts, organelles or molecules under physiological conditions. It is also induced in response to infection, starvation or oxidative stress to provide energy in case of an energy deficit. The aim of this 2-dimensional study was to test if, and if so, how, this process depends on the concentration of cadmium in food (with Cd concentrations from 0 to 352 µg of Cd per g of food (dry weight)-D1 dimension) and the history of selection pressure (160 vs 20 generations of exposure to Cd-D2 dimension). For the study, the 5th instar larvae of a unique strain of the moth Spodoptera exigua that was selected for cadmium tolerance for 160 generations (44 µg of Cd per g of food (dry weight)), as well as 20-generation (11, 22 and 44 µg of Cd per g of food (dry weight)) and control strains, were used. Autophagy intensity was measured by means of flow cytometry and compared with life history parameters: survivability and duration of the 3rd larval stage. The highest values of autophagy markers were found in the groups exposed to the highest Cd concentration and corresponded (with a significant correlation coefficient) to an increased development duration or decreased survivorship in the respective groups. In conclusion, autophagy is probably initiated only if any other defense mechanisms, e.g., antioxidative mechanisms, are not efficient. Moreover, in individuals from pre-exposed populations, the intensity of autophagy is lower.


Assuntos
Autofagia/efeitos dos fármacos , Intoxicação por Cádmio/patologia , Cádmio/toxicidade , Spodoptera/efeitos dos fármacos , Animais , Poluentes Ambientais/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Spodoptera/crescimento & desenvolvimento , Spodoptera/fisiologia
6.
Insects ; 11(6)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503195

RESUMO

This study explores the influence of rosemary, Rosmarinus officinalis (L.) essential oil (EO) on the biochemical (acetylcholinesterase, catalase, and glutathione S-transferase), physiological (oxygen consumption), and behavioral (open field test, repellency) parameters of an important stored product insect: cowpea weevil, Callosobruchus maculatus (F.). R. officinalis EO exhibited effective insecticidal action against C. maculatus even at relatively low concentrations. LC50 = 15.69 µL/L air, and was highly repellent at concentrations equal to or above LC25. Statistically significant inhibition in locomotor activity occurred only after the acute exposure to the EO at LC12.5 and LC25. The oxygen consumption test showed metabolism increase only at LC50. An increase in activity was observed in the case of all three enzymes examined. The presented data provides a potentially valuable resource in designing more environmentally friendly and safer insecticide agents.

7.
Sensors (Basel) ; 20(9)2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375421

RESUMO

Maintaining good condition of dam reservoirs in urban areas seems increasingly important due to their valuable role in mitigating the effects of global warming. The aim of this study is to analyze possibilities to improve water quality and ecosystem condition of the Paprocany dam reservoir (highly urbanized area of southern Poland) using current data of the water parameters, historical sources, and DPSIR (Driver-Pressure-State-Impact-Response) and 3D modeling concerning human activity and the global warming effects. In its history Paprocany reservoir overcame numerous hydrotechnical changes influencing its present functioning. Also, its current state is significantly influenced by saline water from the coal mine (5 g L-1 of chlorides and sulphates) and biogenic elements in recreational area (about 70 mg L-1 of chlorate and to 1.9 mg L-1 Kjeldahl nitrogen) and in sediments (222.66 Mg of Kjeldahl nitrogen, 45.65 Mg of P, and 1.03 Mg of assimilable phosphorus). Concluding, the best solutions to improve the Paprocany reservoir water quality comprise: increasing alimentation with water and shortening the water exchange time, restoration of the 19th century water treatment plant, and wetlands and reed bed area revitalization. The study also proved the applicability of mathematical models in planning of the actions and anticipating their efficiency.

8.
PLoS One ; 14(5): e0216281, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31059541

RESUMO

Two eye-colour mutant strains, white (W) and yellow (Y) of house cricket Acheta domesticus were established in our laboratory. We phenotyped and genotyped the mutants, performed genetic crossings and studied the eye structure and pigment composition using light and electron microscopy and biochemical analysis. We show that W and Y phenotypes are controlled by a single autosomal recessive allele, as both traits are metabolically independent. The analysis of the mutants`eye structure showed a reduced number of dark pigment granules while simultaneously, and an increased amount of light vacuoles in white eye mutants was observed. Significant differences in eye pigment composition between strains were also found. The Y mutant had a lower number of ommochromes, while the W mutant had a lower number of ommochromes and pteridines. This indicates that mutated genes are involved in two different, independent metabolic pathways regulating tryptophan metabolism enzymes, pigment transporter granules or pigment granule formation.


Assuntos
Cor de Olho/genética , Mutação , Animais , Grânulos Citoplasmáticos/metabolismo , Gryllidae , Redes e Vias Metabólicas , Microscopia/métodos , Fenotiazinas/análise , Fenótipo , Pteridinas/análise
9.
C R Biol ; 337(5): 325-31, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24841959

RESUMO

Parnassius apollo (Lepidoptera: Papilionidae) has already disappeared or is under threat of extinction in many of its former habitats. It has been documented that weather conditions--anomalies in particular--contributed to this process. In this study, we combined developmental data obtained previously for the last-instar Apollo larvae (collected in 1996, 1997, and 2003) with corresponding meteorological data to assess the effects of ambient temperature and rainfall episodes on the duration and the completion of the instar. For comparing the temperature effect, we applied the degree-day concept. We found significant positive correlation between the number of rainy days during the instar development (x) and its duration time (y): y=8.293+0.936x (±2.813) (r=0.662, P<10(-7)). Logarithmic transformation of the growth curves of the last-instar Apollo larvae revealed that there was no difference in growth among females; however, there was slower growth of males in 2003 in comparison to 1996. Growth (y) of female Apollo larvae as a function of instar duration (x) can by described by one common equation, irrespectively of the year: y=317.6+502.3 lnx (±263.3) (r=0.82, P<10(-4)).


Assuntos
Borboletas/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Tempo (Meteorologia) , Animais , Peso Corporal , Ingestão de Alimentos , Metabolismo Energético/fisiologia , Feminino , Masculino , Sobrevida
10.
Biomed Eng Online ; 12: 60, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23815984

RESUMO

INTRODUCTION: The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis. MATERIAL AND METHOD: The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurrences of fish on the set trajectory. The data analysis from the sonar concerned automatic recognition of fish using the methods of image analysis and processing. RESULTS: Image analysis algorithm, a mobile robot together with its control in the 2.4 GHz band and full cryptographic communication with the data archiving station was developed as part of this study. For the three model fish ponds where verification of fish catches was carried out (548, 171 and 226 individuals), the measurement error for the described method was not exceeded 8%. SUMMARY: Created robot together with the developed software has features for remote work also in the variety of harsh weather and environmental conditions, is fully automated and can be remotely controlled using Internet. Designed system enables fish spatial location (GPS coordinates and the depth). The purpose of the robot is a non-invasive measurement of the number of fish in water reservoirs and a measurement of the quality of drinking water consumed by humans, especially in situations where local sources of pollution could have a significant impact on the quality of water collected for water treatment for people and when getting to these places is difficult. The systematically used robot equipped with the appropriate sensors, can be part of early warning system against the pollution of water used by humans (drinking water, natural swimming pools) which can be dangerous for their health.


Assuntos
Peixes , Robótica , Som , Qualidade da Água , Algoritmos , Animais , Automação , Fenômenos Químicos , Meio Ambiente , Processamento de Imagem Assistida por Computador , Densidade Demográfica
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