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1.
Animal ; 18(3): 101104, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417217

RESUMO

Delivering piglets is one of the most energy-demanding activities sows undergo in their lifetime. Sows can have myometrial contractions from 2 to 12 h before the first piglet is expelled as well as a nest-building behavior. Thus, when the first piglet is delivered, the female has already used part of her energy supply. When the sow gets exhausted due to lack of energy, the farrowing process can be interrupted, causing damage to the viability and vitality of the piglets. In the present study, we evaluated the effects of feeding sows an energy supplement at the onset of farrowing on farrowing kinetics and piglet vitality. The energy supplement consisted of a blend of carbohydrates and glycerol which provides 439 kJ of metabolizable energy per kg of metabolic weight. A total of 180 sows were used. At the onset of farrowing, sows were assigned to one of the following treatments: sows that were not supplied energy at the onset of farrowing, serving as controls (CON, n = 85); sows fed the energy supplement at the onset of farrowing (ESP, n = 95). Farrowing kinetics, blood glucose concentration, and piglet vitality were recorded for each sow. Blood glucose concentration was assessed by puncturing the auricular vein and using a portable glucometer at four different time points: after the birth of the 1st piglet (T0), and at 20 (T20), 40 (T40), 80 (T80), and 180 (T180) min after the birth of the 1st piglet. The vitality of the 1st, 6th, 12th, 17th, and 20th piglet born was evaluated using the Apgar score. Piglet birth weight and average colostrum intake were measured. The farrowing duration was 20 min shorter (P < 0.05) for ESP sows in comparison with CON sows. Sows from ESP treatment had higher (P ≤ 0.05) blood glucose concentration at T20 and T40 compared to the CON sows. The inter-piglet birth interval was shortened (P < 0.05) by 14 min between the 1st and 2nd piglet for the ESP treatment. The 17th and 20th piglets born from ESP sows had higher (P < 0.05) Apgar score compared to piglets of the same birth order from CON sows. Colostrum intake was higher (P < 0.01) for piglets born from ESP sows. Litter growth performance did not differ (P > 0.05). In conclusion, feeding a blend of carbohydrates and glycerol as an energy supplement for farrowing sows improved farrowing kinetics and piglet vitality score.


Assuntos
Glicerol , Lactação , Gravidez , Animais , Suínos , Feminino , Animais Recém-Nascidos , Glicerol/farmacologia , Glicerol/metabolismo , Glicemia/metabolismo , Colostro/metabolismo
2.
Braz J Biol ; 83: e277798, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126645

RESUMO

In the cropping systems that integrate the corn crop, the insertion of Crotalaria ochroleuca G. Don is predominantly intercropped. In this context, there is a need to observe herbicides that present selectivity for this sunn hemp species. The objective of this study was to evaluate the selectivity of pre and post-emergent herbicides on C. ochroleuca. Two field experiments were conducted in randomized blocks with four replications, involving the pre-emergence and post-emergence application of different herbicide treatments. For the pre-emergent ones, amicarbazone, atrazine and flumioxazin provided phytotoxicity higher than 90% and, consequently, low plant biomass. On the other hand, acetochlor and s-metolachlor did not cause phytotoxicity and did not affect the dry mass of crotalaria. In post-emergence, atrazine + mesotrione showed phytotoxicity >95%, followed by nicosulfuron and 2.4-D with phytotoxicity between 50-60%, whereas tembotrione did not cause injury to the plants. Thus, it was found that among the pre-emergent, acetochlor and s-metolachlor were selective, and for the emerging powders, only tembotrione was the most selective for all parameters analyzed.


Assuntos
Atrazina , Crotalaria , Herbicidas , Herbicidas/toxicidade , Zea mays
3.
Chemosphere ; 307(Pt 1): 135583, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35792207

RESUMO

Ultraviolet radiation (UV) and triclosan (TCS) affect the early development of marine fish; however, the corresponding molecular mechanisms are still not fully understood. Therefore, this work aims to study the effects of the single and combined exposure to these stressors during the thyroid-regulated metamorphosis of the flatfish Solea senegalensis. Sub-lethal exposure (5.89 kJ m-2 UV and/or 0.546 and 1.090 mg L-1 TCS for 48 h) was performed at the beginning of metamorphosis (13 days after hatching, dah), followed by a period in clean media until complete metamorphosis (24 dah). Malformations, metamorphosis progression, length, behavior and the expression of thyroid axis-related genes were studied. TCS induced malformations, decreased swimming performance, and induced metamorphosis acceleration at 15 dah, followed by a significant metamorphosis delay. Such effects were more noticeable in the presence of UV. The down-regulation of five thyroid axis-related genes occurred after exposure to TCS (15 dah), and after 9 days in clean media two genes were still down-regulated. UV exposure increased the effect of TCS by further down-regulating gene expression immediately after the exposure. Since several effects persisted after the period in clean media, implications of these stressors (mainly TCS) on the ecological performance of the species are suggested.


Assuntos
Linguados , Triclosan , Animais , Linguados/genética , Linguados/metabolismo , Larva , Metamorfose Biológica , Triclosan/metabolismo , Raios Ultravioleta
4.
Animal ; 14(6): 1234-1240, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31907084

RESUMO

Progesterone (P4) plays a key role in pregnancy establishment and maintenance; during early pregnancy, P4 stimulates the production and release of uterine secretions necessary for conceptus growth prior to implantation; therefore, exogenous P4 supplementation may improve embryo development. This study evaluated the effects of supplementation during early pregnancy with long-acting injectable progesterone or altrenogest on embryonic characteristics of sows and gilts. Thus, a total of 32 sows and 16 gilts were used. On day 6 of pregnancy sows and gilts were allocated to one of the following groups: non-supplemented; supplemented with 20 mg of altrenogest, orally, from days 6 to 12 of pregnancy; supplemented with 2.15 mg/kg of long-acting injectable progesterone on day 6 of pregnancy. Animals were killed on day 28 of pregnancy, and ovulation rate, embryo survival, embryo weight, crown-to-rump length, uterine glandular epithelium and endometrial vascularization were assessed. Treatments had no effect on pregnancy rate, embryo survival or endometrial vascular density (P > 0.05). Non-supplemented gilts presented larger and heavier embryos compared to gilts from supplemented groups (P < 0.05). Sows in the altrenogest group presented larger and heavier embryos compared to non-supplemented sows and sows supplemented with long-acting injectable progesterone. In conclusion, supplementation of sows and gilts with progestagen from day 6 of pregnancy can be used as a means to improve embryo survival without deleterious effects.


Assuntos
Implantação do Embrião/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Prenhez , Suínos/fisiologia , Acetato de Trembolona/análogos & derivados , Animais , Suplementos Nutricionais , Embrião de Mamíferos , Endométrio , Feminino , Ovulação/fisiologia , Gravidez , Taxa de Gravidez , Prenhez/efeitos dos fármacos , Progestinas/administração & dosagem , Progestinas/farmacologia , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia
5.
Chemosphere ; 235: 885-899, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31284137

RESUMO

Harmful effects of triclosan (TCS) have been reported on several organisms; however, effects on early life stages of marine vertebrates are limited. Therefore, the objective of this work was to assess the effects of TCS during early development of the flatfish Solea senegalensis after initial characterization of cholinesterases (ChEs) and determination of selected biochemical markers baseline levels. Characterization of ChEs and determination of biochemical markers baseline levels of cholinergic activity, energy metabolism and oxidative stress were analysed in sole at 3 days after hatching (dah) and at the onset and end of metamorphosis. To assess TCS effects, fish were exposed during 96h to 30-500 µg L-1 TCS until 3 dah. Fish at 13 dah were exposed during 48h to 200-1,500 µg L-1 TCS and maintained until complete metamorphosis. Effects on survival, malformations, length, metamorphosis progression and biochemical markers were evaluated. The main ChE active form present in sole early life stages is acetylcholinesterase and baseline levels of oxidative stress and energy metabolism biomarkers changed according to fish developmental stage. Triclosan induced malformations (EC50 = 180 µg L-1 at 3 dah), decreased growth (95 µg L-1 at 3 dah; 548 µg L-1 at 24 dah) and affected metamorphosis progression (391 µg L-1 at 17 dah). Impairment of antioxidant system was observed, with TCS affecting catalase at the end of metamorphosis test, however, no oxidative damage on lipids was detected. Glutathione S-transferase was the most sensitive endpoint during early larval test (LOEC = 30 µg L-1). Exposure to TCS affected S. senegalensis at individual and sub-individual levels, both at early larval stage and during the critical period of metamorphosis.


Assuntos
Linguados/embriologia , Larva/efeitos dos fármacos , Metamorfose Biológica/efeitos dos fármacos , Triclosan/toxicidade , Acetilcolinesterase/metabolismo , Animais , Catalase/metabolismo , Colinesterases/metabolismo , Metabolismo Energético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Triclosan/metabolismo
6.
Sci Total Environ ; 628-629: 1395-1404, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30045559

RESUMO

The inclusion of organic UV filters in personal care products (PCPs) has increased in recent years. 4-Methylbenzylidene camphor (4MBC) is one of the most used UV filters, and thus it is commonly found in aquatic ecosystems, with proved negative effects on aquatic organisms. Effects on early life stages of marine vertebrates are largely unknown. Therefore, the main goal of this work was to evaluate 4MBC effects on Senegalese sole (Solea Senegalensis Kaup, 1858) larvae at different levels of biological organization. S. senegalensis were exposed to increasing concentrations of 4MBC from egg stage until 96 h. Mortality, growth, malformations, behaviour and biochemical responses, including enzymatic biomarkers were studied. The exposure to 4MBC until 96 h post-fertilization (hpf) induced mortality and malformations in a dose-response manner. Besides, reduced growth with increasing concentrations was observed. The exposure to 4MBC also caused alterations on behaviour, including overall lower swimming time during light and dark periods. Biomarker alterations caused by 4MBC included imbalance of neurotransmission related endpoints (increased acetylcholinesterase activity) and decreased activity of enzymes related to anaerobic metabolism (lower cellular lactate dehydrogenase activity) at the lower concentrations tested. Furthermore, our results suggest that 4MBC do not induce oxidative stress in S. senegalensis larvae, since catalase and lipid peroxidation levels were not significantly altered by 4MBC. S. senegalensis revealed to be a good model species for vertebrate animal testing in the marine environment. Sub-lethal concentrations of 4MBC induced toxic effects at all organizational levels. Swimming behaviour was a sensitive endpoint and showed that exposure to 4MBC causes impairment on response to light stimulus which is possibly linked with the observed imbalances on cholinesterase activity in larvae. Conservation concerns along distribution range of S. senegalensis should consider that increasing levels of UV filters in marine environment might have impact on the ecology of the species.


Assuntos
Cânfora/análogos & derivados , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cânfora/toxicidade , Linguados/fisiologia , Testes de Toxicidade
7.
Sci Total Environ ; 586: 390-400, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28209406

RESUMO

Evaluation of the effects of linuron and S-metolachlor on apical, biochemical and transcriptional endpoints in zebrafish (Danio rerio) early life stages was the main purpose of this work. Embryos were exposed for 96h to a range of concentrations of each herbicide to determine lethal and sub-lethal effects on apical (e.g. malformations, hatching) and biochemical parameters (cholinesterase, ChE; catalase, CAT; glutathione S-transferase, GST; lipid peroxidation, LPO and lactate dehydrogenase, LDH). To evaluate endocrine disruption effects, embryos were exposed during 96h to 0.88mg/L linuron and 9.66mg/L S-metolachlor, isolated or in binary mixture. Expression of a suite of genes involved in HPT, HPG and HPA-axis was then assessed. Highest concentration of linuron (5.0mg/L) decreased hatching rate to 5% and 70.0mg/L S-metolachlor completely inhibited hatching, about 100%. Both herbicides impaired development by inducing several malformations (100% in 5.0mg/L linuron and 70.0mg/L S-metolachlor). Linuron only affected GST and CAT at concentrations of 0.25 and 0.0025mg/L, respectively. S-metolachlor induced GST (to 256%), inhibited ChE (to 61%) and LDH (to 60%) and reduced LPO levels (to 63%). Linuron isolated treatment seems to have an estrogenic mode of action due to the observed induction of vtg1. Exposure to S-metolachlor seems to interfere with steroidogenesis and with HPT and HPA-axis, since it has inhibited cyp19a2, TSHß and CRH gene expression. In addition to vtg1 induction and CRH inhibition, herbicide combination also induced sox9b that has a role in regulation of sexual development in zebrafish. This study pointed out adverse effects of linuron and S-metolachlor, namely impairment of neurotransmission and energy production, induction of steroidogenesis, and interference with HPT and HPA-axis. These results contributed to elucidate modes of action of linuron and S-metolachlor in zebrafish embryo model. Furthermore, gene expression patterns obtained are indicative of endocrine disruption action of these herbicides.


Assuntos
Acetamidas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Linurona/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Disruptores Endócrinos/toxicidade
8.
Genet Mol Res ; 13(1): 636-48, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24615029

RESUMO

Endometriosis is a complex disease that has both benign and malignant characteristics. It affects 5-10% of women of reproductive age. Studies have demonstrated the existence of common genetic changes in endometriosis and ovarian cancer, suggesting a possible association between these 2 diseases. However, the mechanisms that lead to the development of cancer from endometriosis remain unknown. In this study, we evaluated 3 groups of women: 72 patients with endometriosis, 70 with ovarian cancer, and 70 healthy individuals (controls). Repair (XRCC1 codons 194 and 399, XPD codons 312 and 751, and XRCC3 codon 241)- and metabolism (BLHX codon 443)-related gene polymorphisms were analyzed using the polymerase chain reaction-restriction fragment length polymorphism technique; the efficiency of DNA damage repair was analyzed in vitro in lymphocytes exposed to bleomycin. The logistic regression model was used to evaluate key associations. The results showed an increased average of chromosome breakage in bleomycin-treated lymphocytes from patients with endometriosis and ovarian cancer compared with healthy women. We also detected significant association between XRCC1, XRCC3, and BLHX polymorphisms and a high frequency of chromosomal damage. Women with endometriosis or ovarian cancer may have an altered mechanism of DNA repair, and these defects may be related to a higher incidence of ovarian cancer.


Assuntos
Instabilidade Cromossômica/genética , Cisteína Endopeptidases/genética , Proteínas de Ligação a DNA/genética , Endometriose/genética , Neoplasias Ovarianas/genética , Adulto , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Epidemiologia Molecular , Neoplasias Ovarianas/epidemiologia , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
9.
Curr Med Chem ; 20(2): 257-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23210853

RESUMO

Over the last decades there has been a change in biomedical research with the search for single genes, transcripts, proteins, or metabolites being substituted by the coverage of the entire genome, transcriptome, proteome, and metabolome with the "omics" approaches. The emergence of metabolomics, defined as the comprehensive analysis of all metabolites in a system, is still recent compared to other "omics" fields, but its particular features and the improvement of both analytical techniques and pattern recognition methods has contributed greatly to its increasingly use. The feasibility of metabolomics for biomarker discovery is supported by the assumption that metabolites are important players in biological systems and that diseases cause disruption of biochemical pathways, which are not new concepts. In fact, metabolomics, meaning the parallel assessment of multiple metabolites, has been shown to have benefits in various clinical areas. Compared to classical diagnostic approaches and conventional clinical biomarkers, metabolomics offers potential advantages in sensitivity and specificity. Despite its potential, metabolomics still retains several intrinsic limitations which have a great impact on its widespread implementation - these limitations in biological and experimental measurements. This review will provide an insight to the characteristics, strengths, limitations, and recent advances in metabolomics, always keeping in mind its potential application in clinical/ health areas as a biomarker discovery tool.


Assuntos
Biomarcadores/metabolismo , Metabolômica/tendências , Biomarcadores/análise , Biomarcadores/química , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos
10.
Ecotoxicol Environ Saf ; 73(6): 1231-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20663557

RESUMO

Cadmium (Cd) is a widespread environmental contaminant, strongly mutagenic and known to cause DNA damage in plants. In this work, flow cytometry (FCM) was applied to determine if in vivo exposure to Cd would induce genotoxic effects at the genome level. The hyper-accumulator Thlaspi caerulescens (J. & C. Presl), the related non-accumulator Thlaspi arvense L. and the accumulator crop species Lactuca sativa L. were germinated in distilled water and grown in modified Hoagland's medium with increasing concentrations of Cd(NO3)2 (0, 1, 10 and 100 microM). After 28 days of exposure, shoot and root growth was recorded and the tissues were harvested for Cd and FCM analysis. In general, roots from treated plants contained higher content of Cd than leaves and growth inhibition was observed in the treated plants. Nuclear DNA content was estimated and the G0/G1 full peak coefficient of variation (FPCV), as an indicator of clastogenic damage, was recorded. In T. arvense and T. caerulescens no significant differences were detected between control and exposed plants. Leaves of L. sativa exposed to 10 microM Cd presented a statistically significant increase in FPCV values in comparison with the control group. Furthermore, roots exposed to 100 microM Cd presented a reduction in nuclear DNA content and an increase in FPCV when compared to the control. FCM data indicates that no major DNA damage was induced on both Cd-exposed Thlaspi species and L. sativa leaves. On the contrary, results obtained with L. sativa roots suggests clastogenic damage in these organs exposed to 100 microM of Cd.


Assuntos
Cádmio/toxicidade , Dano ao DNA , Poluentes Ambientais/toxicidade , Lactuca/efeitos dos fármacos , Mutagênicos/toxicidade , Thlaspi/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Lactuca/genética , Lactuca/crescimento & desenvolvimento , Lactuca/metabolismo , Desenvolvimento Vegetal , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas/efeitos dos fármacos , Plantas/genética , Plantas/metabolismo , Especificidade da Espécie , Thlaspi/genética , Thlaspi/crescimento & desenvolvimento , Thlaspi/metabolismo
11.
Ecotoxicol Environ Saf ; 72(3): 811-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18952284

RESUMO

Laboratory and field studies have provided encouraging insights into the capacity of plants to act as biomonitors of environmental quality through the use of biomarkers. However, a better understanding of the overall process of Cd-induced senescence, describing the cascade of Cd effects in plants is needed for a selection of relevant biomarkers of Cd stress. In order to approach this, 5-week old Lactuca sativa L. were exposed for 14 days to 100muM Cd(NO(3))(2) and harvested at days 0, 1, 3, 7 and 14. The parameters measured included classical endpoints (shoot and root growth) and biochemical endpoints related to photosynthesis, nutrients content, and oxidative stress. Cadmium-exposed plants displayed nutrient imbalances in leaves and roots. Photosynthetic efficiency was significantly decreased and lipid peroxidation was enhanced. Antioxidant enzymes were significantly altered during exposure-catalase was inhibited by the end of exposure and peroxidase was induced at day 1 in young leaves. These alterations culminated in a decrease in shoot growth after 14-days exposure to Cd. Biochemical alterations could be used in integrative approaches with classical endpoints in ecotoxicological tests for Cd and after further testing in real scenarios conditions, they could form the basis of a plant biomarkers battery for monitoring and predicting early effects of exposure to Cd.


Assuntos
Compostos de Cádmio/toxicidade , Lactuca/efeitos dos fármacos , Nitratos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Estruturas Vegetais/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Antioxidantes/análise , Antioxidantes/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Catalase/antagonistas & inibidores , Catalase/metabolismo , Clorofila/análise , Clorofila/metabolismo , Monitoramento Ambiental/métodos , Hidroponia , Lactuca/química , Lactuca/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Malondialdeído/análise , Malondialdeído/metabolismo , Fotossíntese/fisiologia , Estruturas Vegetais/crescimento & desenvolvimento , Estruturas Vegetais/metabolismo , Oligoelementos/análise , Oligoelementos/metabolismo
12.
Mutat Res ; 672(2): 90-4, 2009 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19041419

RESUMO

Cadmium (Cd) is a cytotoxic, mutagenic and carcinogenic metal. Mutagenesis is indicative of genetic instability and can be assayed by use of microsatellite markers (simple sequence repeats, SSRs). These are tandem-repeated tracts of DNA composed of units that are 1-6 base pairs (bp) long, spread throughout the genome and highly polymorphic. SSRs can be used in the detection of genomic DNA damage and/or mutational events (e.g. deletions, insertions, point mutations). In order to study chronic exposure to cadmium, Lactuca sativa L. seeds were germinated in distilled water and grown on modified Hoagland's medium, both supplemented with 0, 10 and 100microM Cd(NO(3))(2). After 28 days of exposure, the plants were harvested to assess shoot and root length and accumulation of cadmium. DNA was extracted from young and expanded leaves and roots in order to analyse microsatellite instability (MSI). Mutagenic effects of cadmium were evaluated on nine microsatellite loci. No MSI was found in leaves, but a 2-bp deletion in one lettuce root SSR was detected among the SSRs that were analysed. Thus, SSR analyses may provide a complementary tool in the assessment of different genotoxic effects of compounds on plants.


Assuntos
Cádmio/toxicidade , Lactuca/efeitos dos fármacos , Lactuca/genética , Instabilidade de Microssatélites/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Reação em Cadeia da Polimerase
13.
Rev Bras Enferm ; 54(2): 248-52, 2001.
Artigo em Português | MEDLINE | ID: mdl-12235774

RESUMO

Through the concept of memory by Walter Benjamin, the authors of the present study identify relevant facts of the Brazilian Association of Nursing (ABEn) that affected the development of nursing in Brazil. The investigation points out the participation of ABEn in the regulation of the nursing field, creation of Revista Brasileira de Enfermagem (Brazilian Journal of Nursing), promotion of the Congressos Brasileiros de Enfermagem (Brazilian Congresses of Nursing) and its importance on the political struggle for better health conditions in Brazil.


Assuntos
Enfermagem/tendências , Sociedades de Enfermagem/história , Brasil , História da Enfermagem , História do Século XX , Legislação de Enfermagem/história , Enfermagem/organização & administração , Filosofia em Enfermagem/história , Publicações/história
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