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1.
Braz. j. biol ; 83: e245329, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1285618

RESUMO

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.


Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

2.
Braz J Biol ; 83: e245329, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378663

RESUMO

The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.


Assuntos
Oncorhynchus mykiss , Preservação do Sêmen , Animais , Antioxidantes , Criopreservação , Masculino , Sêmen , Preservação do Sêmen/veterinária , Motilidade Espermática , Espermatozoides
3.
Br J Oral Maxillofac Surg ; 57(7): 632-637, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31200980

RESUMO

This epidemiological study was designed to find out the incidence and factors associated with the occurrence of intraosseous lesions diagnosed at a Reference Centre in Brazil. We included all patients diagnosed with intraosseous lesions (cyst, tumour, bone-associated lesion, and periapical disease) during the period 2006-2017, and analysed the association between some sociodemographic and clinical variables and the types of lesion. There was a total of 290 intraosseous lesions, the most common being odontogenic cysts. There was a significant association between age and odontogenic tumours (p=0.001). In relation to the histopathological diagnosis, root cysts were the most common (n=57), followed by dentigerous cysts (n=26). The lesions studied were seen most often in women between the second and fourth decades of life, odontogenic cysts being the most common type found. We know of few publications of similar epidemiological work, either in Brazil or in the rest of the world, so we suggest that more such studies are made.


Assuntos
Cisto Dentígero/patologia , Cistos Odontogênicos/epidemiologia , Tumores Odontogênicos/epidemiologia , Doenças Estomatognáticas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Brasil/epidemiologia , Criança , Pré-Escolar , Cisto Dentígero/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Cistos Odontogênicos/patologia , Tumores Odontogênicos/patologia , Estudos Retrospectivos , Doenças Estomatognáticas/patologia , Adulto Jovem
4.
Anim Reprod Sci ; 192: 164-170, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29555193

RESUMO

In this article we describe basic aspects of the sperm biology of lebranche mullet (Mugil liza) in the wild and in captivity, in particular assessing the effects of salinity (0, 10, 20, 30, 35, 40, 50 and 60 g L-1) and pH (6, 7, 8, 9 and 10) on sperm motility. Our results indicate that the highest percentage of motility was recorded with salinity 34.6 g L-1 (95 ±â€¯10%) and the longest motility time was obtained with a salinity of 34.8 g L-1 (189 ±â€¯15 s). Variations in the salinity between 30 and 35 g L-1 did not produce any significant alterations in sperm motility; however salinities of 20 and 50 g L-1 produced a significant loss of sperm motility. The highest percentage of motility was obtained at pH 8.5 (93 ±â€¯12%), and the longest motility period at pH 8.7 (218 ±â€¯13 s), while pH lower than or equal to 7 and equal to 10 both produced a significant loss in sperm motility. A positive correlation was found between pH/salinity and the motility percentage (R2 = 0.94 and R2 = 0.97) and motility time (R2 = 0.86 and R2 = 0.98). In seminal and morphometric parameters, statistically significant differences were observed in semen volume, sperm density, plasma membrane integrity and sperm morphometry between the groups studied, showing that the characteristics of the fish have a direct influence on sperm quality. The information generated in this research will be useful for developing biotechnology tools for the effective management of Mugil liza gametes.


Assuntos
Peixes/fisiologia , Salinidade , Espermatozoides/fisiologia , Animais , Animais Selvagens , Aquicultura , Concentração de Íons de Hidrogênio , Masculino , Tolerância ao Sal , Motilidade Espermática/efeitos dos fármacos
5.
Andrologia ; 50(2)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28730739

RESUMO

The knowledge of sperm quality in the broodstock males of different ages is a prerequisite to identify the reproductive ability of cultivated fish for the hatchery management. Thus, in this work, we analysed sperm function of the semen stored of broodstock males of rainbow trout (Oncorhychus mykiss) in different reproductive ages (2, 3 and 4 years old). Sperm samples of each reproductive age were stored in Storfish® during 10 days at 4°C, and then, motility, viability, mitochondrial function (MMP), superoxide anion (O2-) level and DNA fragmentation (DNAfrag ) were assessed. The results demonstrated that sperm function parameters were affected significantly by the age of the males and the time of storage. Motility, viability and MMP significantly decreased, and DNAfrag and O2- level increased with the age increment and the time of storage. In conclusion, sperm quality of 2 and 3 years old were superior to those of 4 years old, based on higher quality of various sperm functions such as motility, viability, MMP, DNA integrity and level O2- during short-term storage. This information must be considered for optimum utilization of broodstock males in aquaculture.


Assuntos
Envelhecimento/fisiologia , Aquicultura/métodos , Oncorhynchus mykiss/fisiologia , Refrigeração/métodos , Preservação do Sêmen/métodos , Animais , Cruzamento/métodos , Fragmentação do DNA , Masculino , Sêmen/fisiologia , Motilidade Espermática/fisiologia , Espermatozoides/fisiologia , Superóxidos/metabolismo
6.
Andrologia ; 50(2)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28758699

RESUMO

Hypobaric hypoxia induces DNA damage in rat testicular cells, the production of defective spermatozoids and decreased sperm count, associated with an increase in oxidative stress. 8-Oxoguanine glycosylase (OGG1) enzymes are main members of the base excision repair (BER) system, a DNA repair mechanism. We determined the expression levels of mitochondrial and nuclear OGG1 isoforms in spermatozoa collected from cauda epididymis in rats exposed to chronic hypobaric hypoxia (CHH) for 5, 15 and 30 days. CHH attenuates OGG1 expression in a time-dependent fashion, with a greater reduction in the mitochondrial isoform OGG1-2a (p < .05). Attenuation of the BER system may contribute to DNA damage under hypoxia exposure.


Assuntos
Dano ao DNA/fisiologia , DNA Glicosilases/metabolismo , Reparo do DNA/fisiologia , Estresse Oxidativo/fisiologia , Espermatozoides/metabolismo , Animais , Hipóxia Celular/fisiologia , Núcleo Celular/metabolismo , Isoenzimas/metabolismo , Masculino , Mitocôndrias/metabolismo , Modelos Animais , Ratos , Espermatozoides/citologia
7.
J Fish Biol ; 89(3): 1537-50, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27406003

RESUMO

The objective of this study was to determine the effect of freezing on the function in Atlantic salmon Salmo salar spermatozoa. The semen was frozen in Cortland's medium + 1.3M dimethyl sulphoxide + 0.3M glucose + 2% bovine serum albumin (final concentration) in a ratio of 1:3 (semen:cryoprotectant) as the treatment (T) and fresh semen as the control (F). Straws of 0·5 ml of sperm suspension were frozen in 4 cm of N2 L. They were thawed in a thermoregulated bath (40° C). After thawing, the percentage of spermatozoa with fragmented DNA [transferase dUTP (deoxyuridine triphosphate) nick-end labelling (TUNEL)], plasma membrane integrity (SYBR-14/PI) and mitochondrial membrane potential (ΔΨMMit, JC-1) were evaluated by flow cytometry and motility was evaluated by optical microscope under stroboscopic light. The fertilization rates of the control and treatment semen were tested at a sperm density of 1·5 × 10(7) spermatozoa oocyte(-1) , by observation of the first cleavages after 16 h incubation at 10° C. In the cryopreserved semen (T), the mean ± s.d. DNA fragmentation was 4·8 ± 2·5%; plasma membrane integrity 75·2 ± 6·3%; mitochondrial membrane potential 51·7 ± 3·6%; motility 58·5 ± 5·3%; curved line velocity (VCL ) 61·2 ± 17·4 µm s(-1) ; average-path velocity (VAP ) 50·1 ± 17·3 µm s(-1) ; straight-line velocity (VSL ) 59·1 ± 18·4 µm s(-1) ; fertilization rate 81·6 ± 1·9%. There were significant differences in the plasma membrane integrity, mitochondrial membrane potential, motility, fertilization rate, VCL , VAP and VSL compared with the controls (P < 0·05). Also the mitochondrial membrane potential correlated with motility, fertilization rate, VCL and VSL (r = 0·75; r = 0·59; r = 0·77 and r = 0·79, respectively; P < 0·05); and the fertilization rate correlated with VCL and VSL (r = 0·59 and r = 0·55, respectively).


Assuntos
Criopreservação , Salmo salar , Preservação do Sêmen , Animais , Crioprotetores , Fertilização , Masculino , Microscopia Confocal , Oócitos , Compostos Orgânicos , Sêmen , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides/fisiologia
8.
Rev. bras. plantas med ; 18(2,supl.1): 613-620, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-830060

RESUMO

ABSTRACT Zinc (Zn) participates of numerous metabolic processes in plants. However, it can become toxic to plants in excessive concentrations in the soil. Pfaffia glomerata is a Brazilian medicinal species that has stood out because of its numerous chemical and functional properties, mainly by the triterpene saponins and ecdysteroids accumulated in its roots. This study aimed to evaluate the effects of zinc excess on many root morphological parameters of Pfaffia glomerata. A 4 x 3 factorial design was employed in a completely randomized scheme with 3 replicates. The treatments consisted of four concentrations of Zn (2, 100, 200, and 300 µM) and three accessions of P. glomerata (BRA, GD, and JB) grown in a hydroponic system for 7 and 14 days. Differences in root morphology and dry mass production were observed among the three accessions in response to excessive Zn. Some growth parameters of GD accession increased with the addition of Zn, ranging from 36 to 79 µM. However, the GD and JB accessions presented reduction in dry mass production, root area, length, and volume with increasing Zn levels. The BRA accession, which had the lowest growth among accessions, presented chlorotic leaves. The shoot/root dry mass ratio and root diameter increased linearly for BRA and GD accessions at 7 days. Based on the evaluated parameters, we observed the following order of Zn excess tolerance in P. glomerata accessions: GD> JB> BRA.


RESUMO O zinco (Zn) participa de numerosos processos metabólicos nas plantas. No entanto, em concentrações excessivas no solo pode tornar-se tóxico para os vegetais. Pfaffia glomerata é uma espécie medicinal brasileira que tem se destacado devido as suas inúmeras propriedades químicas e funcionais, devido principalmente às saponinas triterpênicas e ecdisteróides acumuladas em suas raízes. O objetivo do presente trabalho foi avaliar os efeitos do excesso de Zn sobre vários parâmetros morfológicos radiculares de Pfaffia glomerata. O delineamento experimental utilizado foi o inteiramente casualizado com três repetições, dispostos em um arranjo fatorial (4 x 3). Os tratamentos consistiram em quatro níveis de Zn (2, 100, 200 e 300µM) e três acessos (BRA, GD e JB) de P. glomerata cultivados em sistema hidropônico em casa de vegetação por 7 e 14 dias. Diferenças na morfologia radicular e na produção de material seca foram observadas entre os três acessos em resposta ao excesso de Zn. Alguns parâmetros de crescimento do acesso GD aumentaram sob a adição de Zn variando entre 36 e 79 µM. No entanto, os acessos GD e JB apresentaram redução na matéria seca, bem como na área de superfície, comprimento e volume radicular com o aumento dos níveis de Zn. O acesso BRA, que teve o menor crescimento entre os acessos, apresentou folhas cloróticas. A razão entre matéria seca da parte aérea e raízes e o diâmetro radicular aumentou linearmente para os acessos BRA e GD aos 7 dias de cultivo. Baseando-se nos parâmetros avaliados foi observada a seguinte ordem de tolerância ao excesso de Zn: GD> JB> BRA.


Assuntos
Amaranthaceae , Panax , Zinco/análise , Crescimento , Metais Pesados/análise
9.
Pharmacol Res ; 101: 94-101, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26215469

RESUMO

Hypoxia induces several responses at cardiovascular, pulmonary and reproductive levels, which may lead to chronic diseases. This is relevant in human populations exposed to high altitude (HA), in either chronic continuous (permanent inhabitants) or intermittent fashion (HA workers, tourists and mountaineers). In Chile, it is estimated that 1.000.000 people live at highlands and more than 55.000 work in HA shifts. Initial responses to hypoxia are compensatory and induce activation of cardioprotective mechanisms, such as those seen under intermittent hypobaric (IH) hypoxia, events that could mediate preconditioning. However, whenever hypoxia is prolonged, the chronic activation of cellular responses induces long-lasting modifications that may result in acclimatization or produce maladaptive changes with increase in cardiovascular risk. HA exposure during pregnancy induces hypoxia and oxidative stress, which in turn may promote cellular responses and epigenetic modifications resulting in severe impairment in growth and development. Sadly, this condition is accompanied with an increased fetal and neonatal morbi-mortality. Further, developmental hypoxia may program cardio-pulmonary circulations later in postnatal life, ending in vascular structural and functional alterations with augmented risk on pulmonary and cardiovascular failure. Additionally, permanent HA inhabitants have augmented risk and prevalence of chronic hypoxic pulmonary hypertension, right ventricular hypertrophy and cardiopulmonary remodeling. Similar responses are seen in adults that are intermittently exposed to chronic hypoxia (CH) such as shift workers in HA areas. The mechanisms involved determining the immediate, short and long-lasting effects are still unclear. For several years, the study of the responses to hypoxic insults and pharmacological targets has been the motivation of our group. This review describes some of the mechanisms underlying hypoxic responses and potential therapeutic approaches with antioxidants such as melatonin, ascorbate, omega 3 (Ω3) or compounds that increase the nitric oxide (NO) bioavailability.


Assuntos
Doença da Altitude/tratamento farmacológico , Aclimatação , Adulto , Doença da Altitude/complicações , Doença da Altitude/fisiopatologia , Animais , Antioxidantes/uso terapêutico , Fenômenos Fisiológicos Cardiovasculares , Chile , Doença Crônica , Feminino , Humanos , Recém-Nascido , Masculino , Óxido Nítrico/metabolismo , Estresse Oxidativo , Gravidez , Complicações na Gravidez/fisiopatologia , Reprodução
10.
Theriogenology ; 83(2): 238-45.e2, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25442390

RESUMO

This study was designed to test a vitrification method in Atlantic salmon spermatozoa and determine the capacity of seminal plasma (SP) to protect these cells from cryoinjuries. The vitrification medium consisted of a standard buffer for fish spermatozoa (Cortland medium) + 10% DMSO + 2% BSA + 0.13-M sucrose + SP at concentrations of 30% (G30), 40% (G40), or 50% (G50). Fresh sperm was used as a control. To freeze the samples, 30-µL suspensions of spermatozoa from each group were dropped directly into liquid nitrogen. The resulting spheres were placed in cryotubes for storage in liquid nitrogen. The cryotubes with the vitrified spermatozoa were thawed by placing them in a water bath at 37 °C for 45 seconds. After thawing, the following sperm quality parameters were determined by flow cytometry: DNA fragmentation (terminal deoxynucleotidyl transferase dUTP nick end labeling), plasma membrane integrity (SYBR-14/PI, staining technique), and mitochondrial membrane potential (JC-1 staining). An optical microscope was used to assess subjectively sperm motility, whereas fertility was determined by the presence of neurulation using five replicates per treatment in a sample of 30 eggs. Spermatozoa quality variables were preserved best when the highest concentration of SP (50%) was used (DNA fragmentation, 9.2%; plasma membrane integrity, 98.6%; mitochondrial membrane integrity, 47.2%; motility, 44.1%; and fertility, 46.2%).


Assuntos
Criopreservação/veterinária , Crioprotetores , Salmo salar , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Espermatozoides/fisiologia , Animais , Membrana Celular/fisiologia , Criopreservação/métodos , Fragmentação do DNA , Feminino , Fertilidade , Marcação In Situ das Extremidades Cortadas/veterinária , Masculino , Potencial da Membrana Mitocondrial , Compostos Orgânicos , Preservação do Sêmen/métodos , Motilidade Espermática , Espermatozoides/ultraestrutura
11.
Chem Biol Interact ; 218: 89-98, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24835546

RESUMO

Ischemia-reperfusion (IR) cycle in the myocardium is associated with activation of an injurious cascade, thus leading to new myocardial challenges, which account for up to 50% of infarct size. Some evidence implicates reactive oxygen species (ROS) as a probable cause of myocardial injury in prooxidant clinical settings. Damage occurs during both ischemia and post-ischemic reperfusion in animal and human models. The mechanisms that contribute to this damage include the increase in cellular calcium (Ca(2+)) concentration and induction of ROS sources during reperfusion. Pharmacological preconditioning, which includes pharmacological strategies that counteract the ROS burst and Ca(2+) overload followed to IR cycle in the myocardium, could be effective in limiting injury. Currently widespread evidence supports the use of anesthetics agents as an important cardioprotective strategy that act at various levels such as metabotropic receptors, ion channels or mitochondrial level. Their administration before a prolonged ischemic episode is known as anesthetic preconditioning, whereas when given at the very onset of reperfusion, is termed anesthetic postconditioning. Both types of anesthetic conditioning reduce, albeit not to the same degree, the extent of myocardial injury. This review focuses on cellular and pathophysiological concepts on the myocardial damage induced by IR and how anesthetic pharmacological agents commonly used could attenuate the functional and structural effects induced by oxidative stress in cardiac tissue.


Assuntos
Anestésicos , Fenômenos Fisiológicos Celulares , Traumatismo por Reperfusão/induzido quimicamente , Traumatismo por Reperfusão/fisiopatologia , Animais , Humanos , Precondicionamento Isquêmico Miocárdico , Estresse Oxidativo
12.
Andrologia ; 46(1): 1-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23127143

RESUMO

In Chile, due to the intensive activity developed in confining areas of the Andes Mountains ranging in altitude over 4000 asl, there has been an increasing intermittent movement of human resources to high altitude conditions. This unusual condition, defined as hypobaric hypoxia, affects notoriously in any living organism and there shows a series of physiological responses. Studies performed in rats under chronic hypobaric hypoxia and intermittent hypobaric hypoxia have registered changes in testicular morphology together with loss of spermatogenic cells in all stages of spermatogenic cycle. Furthermore, recent tests reinforced the existence of an oxidative metabolism in epididymis of rats subjected to hypobaric hypoxia due to the increase in the regulator enzyme expression of reactive oxygen species (ROS), This increase in the production of ROS induced a rise in apoptosis at germinal cell level, leading to a state of hypo-spermatogenesis that may jeopardise masculine fertility. Therefore, the eventual development of oxidative stress in spermatogenic cells and consequently the spermatozoids of workers subjected to high altitude, either chronic or intermittent, turns out to be critical when it poses as an imminent risk to the viability and quality of the reproductive cells of workers subjected to intermittent hypobaric hypoxia.


Assuntos
Genitália Masculina/metabolismo , Hipóxia/metabolismo , Estresse Oxidativo , Animais , Humanos , Infertilidade Masculina , Masculino
13.
Andrologia ; 46(7): 766-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23957290

RESUMO

Intermittent hypobaric hypoxia (IHH) induced a decrease in sperm count and oxidative damage in epididymis. We have previously demonstrated that a blueberry-enriched polyphenol extract (BB-4) reduced the adverse effects of oxidative stress in rat testis under hypobaric hypoxia. The aim of this study was to evaluate whether BB-4 could reverse oxidative stress in epididymis. To evaluate the protective role of BB-4 in epididymis, male rats were exposed to IHH. Lipid peroxidation, (LPO) expression and activity of glutathione reductase (GR) were evaluated. Our results showed a reduction in LPO and a decrease in GR activity in rat epididymis exposed to IHH. These results suggest that BB-4 can prevent the effects of IHH in rat epididymis.


Assuntos
Mirtilos Azuis (Planta) , Epididimo/patologia , Hipóxia/prevenção & controle , Animais , Peroxidação de Lipídeos , Masculino , Ratos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
14.
Braz J Microbiol ; 44(2): 523-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294251

RESUMO

The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum) were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control.


Assuntos
Bactérias/metabolismo , Cobre/metabolismo , Microbiologia Industrial/métodos , Consórcios Microbianos
15.
Ecotoxicology ; 22(9): 1403-12, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24068651

RESUMO

Plantlets of Pfaffia glomerata (Spreng.) were exposed for 28 days to three different metal/metalloid (Hg, Pb and As) with different levels (Hg 1; As 25, 50, 100 and Pb 100 and 400 µM) to analyze the possible phytochelatin initiation and affects on growth and photosynthetic pigments vis-à-vis metal accumulation potential of plants. The plantlets showed significant Hg, As and Pb accumulation in roots (150, 1267.67 and 2129 µg g(-1) DW respectively); however, a low root to shoot metal translocation was observed. It was interesting to note that all tested macronutrient (Mg, K, Ca) was higher in shoots and just opposite in case of micronutrients (Cu, Fe, Zn), was recorded highest in roots. The growth of plantlets (analyzed in terms of length and dry weight) was negatively affected by various metal treatments. In addition, the level of photosynthetic pigments alters significantly in response to all metal/metalloid treatment. In response to all tested metal/metalloids in plants only As induced phytochelatins (PC2, PC3 and PC4) in roots, and in shoots, GSH was observed in all tested metal/metalloids. In conclusion, P. glomerata plantlets could not cooperatively induce phytochelatins under any of Hg and Pb levels.


Assuntos
Amaranthaceae/efeitos dos fármacos , Metais Pesados/toxicidade , Fitoquelatinas/metabolismo , Amaranthaceae/crescimento & desenvolvimento , Amaranthaceae/metabolismo , Biomassa , Carotenoides/metabolismo , Clorofila/metabolismo , Fotossíntese/efeitos dos fármacos , Testes de Toxicidade
16.
Braz. j. microbiol ; 44(2): 523-528, 2013. graf
Artigo em Inglês | LILACS | ID: lil-688565

RESUMO

The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum) were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control.


Assuntos
Bactérias/metabolismo , Cobre/metabolismo , Microbiologia Industrial/métodos , Consórcios Microbianos
17.
Artigo em Inglês | MEDLINE | ID: mdl-21869902

RESUMO

To evaluate the effectiveness of Uncaria tomentosa in minimizing the side effects of chemotherapy and improving the antioxidant status of colorectal cancer (CRC) patients, a randomized clinical trial was conducted. Patients (43) undergoing adjuvant/palliative chemotherapy with 5-Fluorouracil/leucovorin + oxaliplatin (FOLFOX4) were split into two groups: the UT group received chemotherapy plus 300 mg of Uncaria tomentosa daily and the C group received only FOLFOX4 and served as a control. Blood samples were collected before each of the 6 cycles of chemotherapy, and hemograms, oxidative stress, enzymes antioxidants, immunologic parameters, and adverse events were analyzed. The use of 300 mg of Uncaria tomentosa daily during 6 cycles of FOLFOX4 did not change the analyzed parameters, and no toxic effects were observed.

18.
Andrologia ; 37(1): 47-52, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15644063

RESUMO

In order to evaluate the effects of the exposition to continuous chronic hypobaric hypoxia (CCHH) and intermittent chronic hypobaric hypoxia (ICHH) on testis histology and on oxidative metabolism of spermatogenic cells (SC), male rats were exposed to a 4600-m simulated altitude (PO2: 89.6 mmHg). After 60 days, ICHH and CCHH groups presented a significant decrease in testicular mass, an increase in interstitial space, a decrease in height of the seminiferous epithelium, depletion of cellular elements, vacuolization in epithelial cells and folding of the basal membrane. Round spermatids from animals exposed to CCHH presented a significant decrease in energy-dependent cell shape changes. Round spermatid mitochondria of CCHH rats seem to be limited in their ability to handle reducing equivalents. These mitochondria also appear to be uncoupled under basal conditions. Round spermatids from CCHH rats evidence large oxygen consumption (QO2) insensitive to inhibition by cyanide, a process that could be partly related to lipoperoxidation. Thus, exposure of male rats to CCHH and ICHH induced evident changes in testicular morphology and loss of spermatogenic cells, in all stages of the spermatogenic cycle. This post-meiotic spermatogenic cell loss in the testis correlated well with metabolic changes in round spermatids that evidenced a strong metabolic stress in these cells.


Assuntos
Hipóxia/patologia , Espermátides/metabolismo , Testículo/anatomia & histologia , Animais , Doença Crônica , Hipóxia/metabolismo , Masculino , Oxirredução , Oxigênio/metabolismo , Ratos , Ratos Wistar , Testículo/patologia
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