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1.
Sensors (Basel) ; 19(24)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842500

RESUMO

This article presents the design and implementation of an event-triggered control approach, applied to the leader-following consensus and formation of a group of autonomous micro-aircraft with capabilities of vertical take-off and landing (VTOL-UAVs). The control strategy is based on an inner-outer loop control approach. The inner control law stabilizes the attitude and position of one agent, whereas the outer control follows a virtual leader to achieve position consensus cooperatively through an event-triggered policy. The communication topology uses undirected and connected graphs. With such an event-triggered control, the closed-loop trajectories converge to a compact sphere, centered in the origin of the error space. Furthermore, the minimal inter-sampling time is proven to be below bounded avoiding the Zeno behavior. The formation problem addresses the group of agents to fly in a given shape configuration. The simulation and experimental results highlight the performance of the proposed control strategy.

2.
Eur J Pharm Biopharm ; 104: 140-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27131753

RESUMO

Public health concerns continue to exist over the safety of zinc oxide nanoparticles that are commonly used in sunscreen formulations. In this work, we assessed the effects of two conditions which may be encountered in everyday sunscreen use, occlusion and a compromised skin barrier, on the penetration and local toxicity of two topically applied zinc oxide nanoparticle products. Caprylic/capric triglyceride (CCT) suspensions of commercially used zinc oxide nanoparticles, either uncoated or with a silane coating, were applied to intact and barrier impaired skin of volunteers, without and with occlusion for a period of six hours. The exposure time was chosen to simulate normal in-use conditions. Multiphoton tomography with fluorescence lifetime imaging was used to noninvasively assess zinc oxide penetration and cellular metabolic changes that could be indicative of toxicity. We found that zinc oxide nanoparticles did not penetrate into the viable epidermis of intact or barrier impaired skin of volunteers, without or with occlusion. We also observed no apparent toxicity in the viable epidermis below the application sites. These findings were validated by ex vivo human skin studies in which zinc penetration was assessed by multiphoton tomography with fluorescence lifetime imaging as well as Zinpyr-1 staining and toxicity was assessed by MTS assays in zinc oxide treated skin cryosections. In conclusion, applications of zinc oxide nanoparticles under occlusive in-use conditions to volunteers are not associated with any measurable zinc oxide penetration into, or local toxicity in the viable epidermis below the application site.


Assuntos
Nanopartículas , Absorção Cutânea , Óxido de Zinco/administração & dosagem , Administração Tópica , Feminino , Humanos
3.
Eur J Trauma Emerg Surg ; 41(2): 129-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26038256

RESUMO

INTRODUCTION: Man's inhumanity for man still knows no boundaries, as we continue as a species as a whole to engage in war. According to Kohn's Dictionary of Wars [1], of over 3,700 years of recorded history, there have been a total of 3,010 wars. One is hard pressed to actually find a period of time in which here has not been an active conflict in the globe. The world has experienced two world wars: WWI (1914-1918) and WWII (1939-1945). The total number of military casualties in WWI was over 37 million, while WWII so far, has been the deadliest military conflict in history with over 60 million people killed accounting for slightly over 2.5% of the world's population. MATERIAL AND METHODS: The purpose of this study is to review contemporary wars and their contributions to vascular injury management. It is precisely wartime contributions that have led to the more precise identification and management of these injuries resulting in countless lives and extremities saved. However, surgeons dealing with vascular injuries have faced a tough and arduous road. Their journey was initiated by surgical mavericks which undaunted, pressed on against all odds guided by William Stewart Halsted's classic statement in 1912: "One of the chief fascinations in surgery is the management of wounded vessels." CONCLUSION: Contemporary wars of the XX-XXI centuries gave birth, defined and advanced the field of vascular injury management.


Assuntos
Medicina Militar/história , Militares/história , Lesões do Sistema Vascular/história , Lesões Relacionadas à Guerra/história , Guerra , Extremidades/irrigação sanguínea , História do Século XX , História do Século XXI , Humanos , Medicina Militar/tendências , Lesões do Sistema Vascular/terapia , Lesões Relacionadas à Guerra/terapia
4.
Environ Toxicol Pharmacol ; 38(2): 672-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25238107

RESUMO

Today, the list of endocrine disrupting compounds (EDCs) in freshwater and marine environments that mimic or block endogenous hormones is expanding at an alarming rate. As immune and reproductive systems may interact in a bidirectional way, some authors proposed the immune capacities as attractive markers to evaluate the hormonal potential of environmental samples. Thus, the present work proposed to gain more knowledge on direct biological effects of natural and EDCs on female fish splenic leucocyte non-specific immune activities by using ex vivo assays. After determining the optimal required conditions to analyze splenic immune responses, seven different EDCs were tested ex vivo at 0.01, 1 and 100nM over 12h on the leucocyte functions of female three-spined stickleback, Gasterosteus aculeatus. In summary, we found that natural hormones acted as immunostimulants, whilst EDCs were immunosuppressive.


Assuntos
Disruptores Endócrinos/toxicidade , Leucócitos/imunologia , Baço/imunologia , Poluentes Químicos da Água/toxicidade , Androgênios/farmacologia , Androgênios/toxicidade , Animais , Compostos Benzidrílicos/toxicidade , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Estrogênios/farmacologia , Estrogênios/toxicidade , Feminino , Imunidade Inata/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Metiltestosterona/toxicidade , Fenóis/toxicidade , Smegmamorpha/embriologia , Smegmamorpha/imunologia , Baço/efeitos dos fármacos , Acetato de Trembolona/toxicidade
5.
Environ Sci Pollut Res Int ; 21(22): 13103-17, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24996940

RESUMO

Aluminium is used in diverse anthropogenic processes at the origin of pollution events in aquatic ecosystems. In the Champagne region (France), high concentrations of aluminium (Al) are detected due to vine-growing practices. In fish, little is known about the possible immune-related effects at relevant environmental concentrations. The present study analyzes the simultaneous effects of aluminium and bacterial lipopolysaccharide (LPS), alone and in combination, on toxicological biomarkers in the freshwater fish species Rutilus rutilus. For this purpose, roach treated or not with LPS were exposed to environmental concentrations of aluminium (100 µg/L) under laboratory-controlled conditions for 2, 7, 14 and 21 days. After each exposure time, we assessed hepatic lipoperoxidation, catalase activity, glutathione reductase activity and total glutathione content. We also analyzed cellular components related to the LPS-induced inflammatory response in possible target tissues, i.e. head kidney and spleen. Our results revealed a significant prooxidant effect in the liver cells and head kidney leukocytes of roach exposed to 100 µg of Al/L for 2 days. In liver, we observed more lipoperoxidation products and lower endogenous antioxidant activity levels such as glutathione reductase activity and total glutathione content. These prooxidant effects were associated with a higher oxidative burst in head kidney leukocytes, and they were all the more important in fish stimulated by LPS injection. These findings demonstrate that environmental concentrations of Al induce oxidative and immunotoxic effects in fish and are associated to an immunomodulatory process related to the inflammatory response.


Assuntos
Compostos de Alúmen/toxicidade , Cyprinidae/imunologia , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Compostos de Alúmen/metabolismo , Animais , Cyprinidae/metabolismo , Feminino , Água Doce/química , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Estresse Oxidativo/imunologia , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória , Poluentes Químicos da Água/metabolismo
6.
Am J Hum Biol ; 26(5): 710-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24889785

RESUMO

OBJECTIVES: Amerindians have a particularly high propensity to overweight and obesity as they change lifestyle and experience a nutrition transition. The aim of this study was to evaluate the effects of transculturation on nutritional status in three Amazonian Amerindian villages. METHODS: Nutritional status was assessed in 232 volunteers: 65 Yanomami from an isolated village and 167 Guahibo subjects from villages with intermediate and high levels of transculturation. RESULTS: There was a significant pattern of decreasing stunting and increasing overweight and obesity across the gradient of transculturation. From the jungle Yanomami to the intermediate and transculturated Guahibo, stunting was respectively 72, 55, and 39%, and children /adult overweight was 0, 3/44, and 15/89%. These anthropometric-based patterns were confirmed by bioimpedance vector analysis. CONCLUSIONS: Transculturation in these Amerindian populations is associated with an increase in overweight and obesity coexisting with undernourished children.


Assuntos
Aculturação , Estado Nutricional , Sobrepeso/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Indígenas Sul-Americanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/etiologia , Sobrepeso/etiologia , Venezuela/epidemiologia , Adulto Jovem
7.
Am J Transplant ; 14(6): 1383-90, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24801862

RESUMO

Determining risk for recurrence of hepatocellular carcinoma (HCC) following liver transplantation (LT) is an important clinical need. We assessed consecutive patients who underwent LT for HCC following sequential transarterial chemoembolization (TACE). Treatment response was assessed using modified response evaluation criteria in solid tumors (mRECIST) categories: complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Cox proportional hazard models were used to predict HCC recurrence. One hundred seventy-three patients underwent TACE and imaging to assess response prior to LT. TACE responses were: CR = 23.7%, PR = 24.3%, SD = 27.7% and PD = 24.3%. Five-year HCC recurrence rate was 5.3% in patients responding to TACE (CR/PR), versus 17.6%, among patients who did not respond (SD/PD, p = 0.014). In multivariate analysis, independent pre-LT predictors of recurrence were response to TACE and largest radiologic size of tumor (>3 cm vs. ≤3 cm). HCC recurrence rate for patients with tumor size >3 cm and no response to TACE was 35.8%, compared with 1.9% for patients with tumor size ≤3 cm and response to TACE (p = 0.0007). We conclude that mRECIST criteria and tumor size differentiate patients with high or low likelihood of HCC recurrence after LT. These findings raise the possibility of incorporating response to TACE and largest tumor size to identify patients at highest risk for HCC recurrence.


Assuntos
Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica , Neoplasias Hepáticas/patologia , Idoso , Carcinoma Hepatocelular/terapia , Feminino , Humanos , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva
8.
J Dairy Sci ; 97(5): 3081-98, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24612807

RESUMO

Feeding 56 versus 0 g/d of Saccharomyces cerevisiae fermentation product (SCFP; Diamond V Original XP; Diamond V, Cedar Rapids, IA) can increase feed intake and milk production in transition dairy cows. To evaluate the effects of various dosages of SCFP, Holstein cows were given individually a supplement containing 0 (n=14), 56 (n=15), or 112 g (n=13) of SCFP daily during morning lockup as a topdressing to their total mixed ration. The supplement consisted of 0, 56, or 112 g of SCFP mixed with 84 g of molasses and 168, 112, or 56 g of corn meal, respectively. Supplement feeding began 28 d before predicted calving date (no less than 14 d) and ended 28 d postpartum, and supplement intake was evaluated daily. Blood samples were collected at d -21, -14, -7, -3, -1, 0, 1, 3, 7, 14, 21, and 28 to measure serum concentrations of macrominerals, metabolites, acute-phase proteins, immunoglobulin, and hormones. Milk weights were measured and milk samples were collected 2 times/wk on nonconsecutive days and analyzed for milk fat, protein, lactose, and somatic cell count (SCC). During the first day after calving, feeding SCFP versus no SCFP decreased serum cortisol concentrations and at least tended to increase supplement intake and serum concentrations of calcium, glucose, urea N, and serum amyloid A. During the first 4 wk postpartum, feeding SCFP versus no SCFP decreased milk SCC and increased milk production and serum phosphorus concentrations. Feeding 112 versus 56 g of SCFP/d did not show additional effects. Feeding SCFP may have a dosage-independent beneficial effect in supporting the physiologic adaptations after parturition, resulting in higher milk production and lower milk SCC.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Lactação/fisiologia , Saccharomyces cerevisiae/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Feminino , Fermentação , Leite , Parto , Período Pós-Parto
9.
Fish Physiol Biochem ; 40(4): 1021-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24379163

RESUMO

Tropical gar (Atractosteus tropicus) is an economically and socially important freshwater species from Southeastern Mexico, with a high aquaculture potential. With this in mind, the purpose of this study was to characterize the digestive proteases of tropical gar juveniles through biochemical and electrophoretic analyses. Twenty specimens with an average weight of 73.6 ± 12.7 g were used to obtain stomach and intestinal tissue from which multienzymatic extracts were prepared. The general activities of the acid and alkaline proteases were evaluated, as well as the specific activities of trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A. The effect of the pH and temperature on the proteases was also analyzed, together with the composition of the multienzymatic extracts using protease inhibitors and electrophoretic tests. Results showed that A. tropicus have a functional stomach in which protein hydrolysis starts with pepsin and which contains endo- and exopeptidases (trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A) and proteases that are resistant to high temperatures (45 and 55 °C for alkaline and acid proteases, respectively) and pH values. Using zymogram technique, we found two acid protease isoforms (0.35 and 0.71 rf) and five alkaline protease isoforms (83.7, 43.7, 27.5, 24.0 and 19.4 kDa), which decrease or disappear with the different inhibitors. Thus, this species is considered to be a carnivore capable of adapting to its environment by consuming different types of proteins from preys and also could adapt rapidly to consume a compound diet with different animal protein sources.


Assuntos
Digestão/fisiologia , Peixes/metabolismo , Trato Gastrointestinal/enzimologia , Peptídeo Hidrolases/metabolismo , Animais , Aquicultura/métodos , Carboxipeptidases A/metabolismo , Quimotripsina/metabolismo , Eletroforese/veterinária , Peixes/fisiologia , Concentração de Íons de Hidrogênio , Isoenzimas/metabolismo , Leucil Aminopeptidase/metabolismo , México , Estatísticas não Paramétricas , Temperatura , Tripsina/metabolismo
10.
Oncogene ; 33(25): 3298-306, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23912460

RESUMO

Despite the progress made in targeted anticancer therapies in recent years, challenges remain. The identification of new potential targets will ensure that the arsenal of cancer therapies continues to expand. FAM83B was recently discovered in a forward genetic screen for novel oncogenes that drive human mammary epithelial cell (HMEC) transformation. We report here that elevated FAM83B expression increases Phospholipase D (PLD) activity, and that suppression of PLD1 activity prevents FAM83B-mediated transformation. The increased PLD activity is engaged by hyperactivation of epidermal growth factor receptor (EGFR), which is regulated by an interaction involving FAM83B and EGFR. Preventing the FAM83B/EGFR interaction by site-directed mutation of lysine 230 of FAM83B suppressed PLD activity and MAPK signaling. Furthermore, ablation of FAM83B expression from breast cancer cells inhibited EGFR phosphorylation and suppressed cell proliferation. We propose that understanding the mechanism of FAM83B-mediated transformation will provide a foundation for future therapies aimed at targeting its function as an intermediary in EGFR, MAPK and mTOR activation.


Assuntos
Receptores ErbB/metabolismo , Proteínas de Neoplasias/metabolismo , Oncogenes/genética , Fosfolipase D/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Processos de Crescimento Celular/fisiologia , Linhagem Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Ativação Enzimática , Células Epiteliais/metabolismo , Receptores ErbB/genética , Feminino , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas de Neoplasias/genética , Fosfolipase D/genética , Fosforilação , Transdução de Sinais
11.
Ecotoxicology ; 22(5): 815-24, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23744483

RESUMO

Data regarding the link between DNA integrity of germ cells and the quality of progeny in fish exposed to genotoxicant are scarce although such information is of value to understand genotoxic effects of contaminants in aquatic fauna. This work aimed at studying the consequences of a parental exposure during the breeding season on offspring quality in three-spined stickleback. After in vivo exposure of adult fish to methyl methane sulfonate, a model alkylating compound, a clear increase in DNA damage was observed in erythrocytes of both genders, here used as a biomarker of exposure. MMS exposure significantly affected sperm DNA integrity but neither female fecundity nor fertilization success. In order to understand the contribution of each sex to potential deleterious effects in progeny due to parental exposure, mating of males and females exposed or not to MMS, was carried out. Exposure of both males and females or of males alone led to a significant increase in both mortality during embryo-larval stages and abnormality rate at hatching that appeared to be sensitive stages. Thus, in accordance with recent studies carried out in other freshwater fish species, such development defects in progeny were clearly driven by male genome, known to be devoid of DNA repair capacity in spermatozoa. The next step will be to investigate the link between DNA damage in stickleback sperm and reproductive impairment in natural populations exposed to complex mixture of genotoxicants.


Assuntos
Exposição Materna/efeitos adversos , Metanossulfonato de Metila/toxicidade , Mutagênicos/toxicidade , Óvulo/efeitos dos fármacos , Exposição Paterna/efeitos adversos , Espermatozoides/efeitos dos fármacos , Poluentes da Água/toxicidade , Anormalidades Induzidas por Medicamentos , Animais , Dano ao DNA , Feminino , Masculino , Reprodução/efeitos dos fármacos , Smegmamorpha/fisiologia
12.
Br J Cancer ; 108(8): 1624-33, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23531700

RESUMO

BACKGROUND: Dichloroacetate (DCA), through the inhibition of aerobic glycolysis (the 'Warburg effect') and promotion of pyruvate oxidation, induces growth reduction in many tumours and is now undergoing several clinical trials. If aerobic glycolysis is active in multiple myeloma (MM) cells, it can be potentially targeted by DCA to induce myeloma growth inhibition. METHODS: Representative multiple myeloma cell lines and a myeloma-bearing mice were treated with DCA, alone and in combination with bortezomib. RESULTS: We found that aerobic glycolysis occurs in approximately half of MM cell lines examined, producing on average 1.86-fold more lactate than phorbol myristate acetate stimulated-peripheral blood mononuclear cells and is associated with low-oxidative capacity. Lower doses of DCA (5-10 mM) suppressed aerobic glycolysis and improved cellular respiration that was associated with activation of the pyruvate dehydrogenase complex. Higher doses of DCA (10-25 mM) induced superoxide production, apoptosis, suppressed proliferation with a G0/1 and G2M phase arrest in MM cell lines. In addition, DCA increased MM cell line sensitivity to bortezomib, and combinatorial treatment of both agents improved the survival of myeloma-bearing mice. CONCLUSION: Myeloma cells display aerobic glycolysis and DCA may complement clinically used MM therapies to inhibit disease progression.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácidos Borônicos/farmacologia , Cloroacetatos/farmacologia , Glicólise/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Pirazinas/farmacologia , Aerobiose , Animais , Apoptose/efeitos dos fármacos , Ácidos Borônicos/administração & dosagem , Bortezomib , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cloroacetatos/administração & dosagem , Sinergismo Farmacológico , Humanos , Camundongos , Consumo de Oxigênio , Pirazinas/administração & dosagem , Complexo Piruvato Desidrogenase/antagonistas & inibidores , Complexo Piruvato Desidrogenase/metabolismo , Superóxidos/metabolismo
13.
Am J Transplant ; 13(2): 363-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23137119

RESUMO

Obesity is increasingly common before and after liver transplantation (LT), yet optimal management remains unclear. Our aim was to analyze the effectiveness of a multidisciplinary protocol for obese patients requiring LT, including a noninvasive pretransplant weight loss program, and a combined LT plus sleeve gastrectomy (SG) for obese patients who failed to lose weight prior to LT. Since 2006, all patients referred LT with a BMI > 35 were enrolled. There were 37 patients who achieved weight loss and underwent LT alone, and 7 who underwent LT combined with SG. In those who received LT alone, weight gain to BMI > 35 was seen in 21/34, post-LT diabetes (DM) in 12/34, steatosis in 7/34, with 3 deaths plus 3 grafts losses. In patients undergoing the combined procedure, there were no deaths or graft losses. One patient developed a leak from the gastric staple line, and one had excess weight loss. No patients developed post-LT DM or steatosis, and all had substantial weight loss (mean BMI = 29). Noninvasive pretransplant weight loss was achieved by a majority, though weight gain post-LT was common. Combined LT plus SG resulted in effective weight loss and was associated with fewer post-LT metabolic complications. Long-term follow-up is needed.


Assuntos
Derivação Gástrica/métodos , Falência Hepática/terapia , Transplante de Fígado/métodos , Obesidade/cirurgia , Adulto , Idoso , Índice de Massa Corporal , Endoscopia/métodos , Feminino , Gastrectomia/métodos , Humanos , Falência Hepática/complicações , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Fatores de Risco , Resultado do Tratamento , Redução de Peso
14.
Reprod Toxicol ; 36: 6-11, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23178896

RESUMO

Many xenobiotics released in the aquatic environment exhibit a genotoxic potential toward organisms. Long term exposure to such compounds is expected to lead to multigenerational reproductive defects, further influencing the recruitment rate and hence, the population dynamics. Paternal exposure to genotoxicants was previously shown to increase abnormal development in the progeny of mammalian or aquatic species. The aim of this study was to evaluate the relationship between DNA damage in sperm of the fish three-spined stickleback and progeny developmental defects. Spermatozoa were exposed ex vivo to an alkylating agent (methyl methanesulfonate) before in vitro fertilization and DNA damage was assessed by the alkaline comet assay. A significant relationship between abnormal development and sperm DNA damage was underlined. This study illustrates the interest to use germ cell DNA damage after ex vivo exposure to evaluate the impact of genotoxic compounds on progeny fitness in aquatic organisms.


Assuntos
Alquilantes/toxicidade , Dano ao DNA , Desenvolvimento Embrionário/efeitos dos fármacos , Mutagênicos/toxicidade , Exposição Paterna/efeitos adversos , Smegmamorpha/embriologia , Espermatozoides/efeitos dos fármacos , Animais , Antineoplásicos Alquilantes/toxicidade , Ensaio Cometa , Embrião não Mamífero/anormalidades , Embrião não Mamífero/efeitos dos fármacos , Fertilização in vitro/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Metanossulfonato de Metila/toxicidade , Testes de Mutagenicidade/métodos , Concentração Osmolar , Distribuição Aleatória , Smegmamorpha/anormalidades , Smegmamorpha/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade
15.
J Dairy Sci ; 95(10): 6027-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22921623

RESUMO

The purpose of this study was to use meta-analytic methods to estimate the effect of a commercially available yeast culture product on milk production and other production measures in lactating dairy cows using a meta-analysis of randomized controlled trials. Sixty-one research publications (published journal articles, published abstracts, and technical reports) were identified through a review of literature provided by the manufacturer and a search of published literature using 6 search engines. Thirty-six separate studies with 69 comparisons met the criteria for inclusion in the meta-analysis. The fixed-effect meta-analysis showed substantial heterogeneity for milk yield, energy-corrected milk, 3.5% fat-corrected milk, milk fat yield, and milk protein yield. Sub-group analysis of the data showed much less heterogeneity in peer-reviewed studies versus non-peer-reviewed abstracts and technical reports, and tended to show higher, but not significantly different, treatment effects. A random-effects meta-analysis showed estimated raw mean differences between treated and untreated cattle reported in peer-reviewed publications of 1.18 kg/d [95% confidence interval (CI): 0.55 to 1.81], 1.61 kg/d (95% CI: 0.92 to 2.29), and 1.65 kg/d (95% CI: 0.97 to 2.34) for milk yield, 3.5% fat-corrected milk, and energy-corrected milk, respectively. Milk fat yield and milk protein yield for peer-reviewed studies showed an increase in the raw mean difference of 0.06 kg/d (95% CI: 0.01 to 0.10) and 0.03 kg/d (95% CI: 0.00 to 0.05), respectively. Estimated raw mean dry matter intake of the peer-reviewed studies during early lactation (<70 d in milk) and not-early lactation were 0.62 kg/d (95% CI: 0.21 to 1.02) and a decrease of 0.78 kg/d (95% CI: -1.36 to -0.21), respectively. These findings provide strong evidence that this commercially available yeast culture product provides significant improvement in several important milk production outcomes as evaluated in production settings typical for commercial dairies in North America. Utilizing meta-analytic methods to study the complete breadth of information relating to a specific treatment by studying multiple overcomes of all eligible studies can reduce the uncertainty often seen in small individual studies designed without sufficient power to detect differences in treatments.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Lactação/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Anaerobiose/fisiologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Bovinos/metabolismo , Feminino , Fermentação/fisiologia
16.
Ecotoxicol Environ Saf ; 80: 45-53, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22381616

RESUMO

Juvenile turbot were exposed in laboratory conditions to a mixture of chemical contaminants associated with harbour and estuarine sediments for seven and 21 days. Several molecular biomarkers of exposure were then measured in fish liver: two biotransformation parameters [ethoxyresorufin-O-deethylase (EROD) and phase II glutathione S-transferase (GST) activities] and an antioxidant enzyme activity [catalase (CAT)]. Modifications at the histological level were analysed by the measurement of the number and size of melanomacrophage centres (MMCs) and disturbances to the immune function by the measurement of cytokine transforming growth factor-beta (TGF-ß) and development of the thymus. The responses of these molecular and immunological biomarkers were correlated with metal and PAH concentrations measured in sediments and with the physiological performance of turbot analysed in a previous study on the same fish (growth rates, condition factor K, RNA:DNA ratio and lipid index). While no difference was found in thymus analysis, some molecular and immunological responses were observed in fish exposed to contaminated sediments. Weak relationships between molecular biomarkers' responses and PAH concentrations were recorded, while their responses were significantly correlated with some metals. MMC and aggregates were weakly related to chemical contaminants whereas some significant correlations were found between TGF-b1 responses and some metal concentrations. However, molecular and immunological biomarkers were weakly related to fish physiological damages since low responses were observed in the condition which led to the lowest growth and condition indices. These data suggest the complexity of cause-effect relationships between exposure to pollutants, metabolisms and health damages. Precautions should be considered in the use of molecular and immunological biomarkers alone in biomonitoring programs. Their complementary use with physiological biomarkers, such as fish growth and condition indices, could improve their utilisation.


Assuntos
Sedimentos Geológicos/química , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental/métodos , Linguados , Glutationa Transferase/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Metais/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Fator de Crescimento Transformador beta/metabolismo
18.
Chemosphere ; 87(7): 692-702, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22236592

RESUMO

In the present study, juvenile sea bass were exposed for 48 and 96 h to an Arabian light crude oil and their responses were assessed at the molecular and physiological levels. The aim of the study was therefore to assess (i) the short term effects of crude oil exposure by the measurement of several molecular biomarkers, (ii) the consequences of this short term exposure on fish health by using growth and condition indices measured after a decontamination period of 28 and 26 d in seawater. Hydrocarbon petroleum concentrations was monitored during the 96 h experiments and an increase of PAH concentrations were found in fish following both exposure times. An 7-ethoxyresorufin-O-deethylase (EROD) induction was observed after 48 h of exposure, while a significant decrease in the sea bass specific growth rate in length and for the RNA:DNA ratio was observed 28 d after that exposure ceased. The EROD induction doubled after the 96 h exposure, and a significant increase in GST activities was observed. A significant decrease in the specific growth rates, the otolith recent growth, the RNA:DNA ratio and the Fulton's K condition index were then observed in sea bass 26 d after the 96 h exposure to mechanically dispersed crude oil compared to the control. The present study shows that growth and condition indices can prove useful in assessing fish health status following an oil spill. Their complementary analysis with sensitive molecular biomarkers as EROD could improve the determination of oil spill impact on fish populations.


Assuntos
Bass/fisiologia , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Glutationa Transferase/metabolismo , Petróleo/análise , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar/química , Estresse Fisiológico , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
19.
Fish Physiol Biochem ; 38(2): 441-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21671023

RESUMO

Common snook (Centropomus undecimalis) is one of the most important marine species under commercial exploitation in the Gulf of Mexico; for this reason, interest in developing its culture is a priority. However, larviculture remains as the main bottleneck for massive production. In this sense, our objective was to determine the changes of digestive enzymes activities using biochemical and electrophoretic techniques during 36 days of Common snook larviculture fed with live preys (microalgae, rotifers, and Artemia). During larviculture, all digestive enzymatic activities were detected with low values since yolk absorption, 2 days after hatching (dah) onwards. However, the maximum values for alkaline protease (6,500 U mg protein(-1)), trypsin (0.053 mU × 10(-3) mg protein(-1)), and Leucine aminopeptidase (1.4 × 10(-3) mU mg protein(-1)) were detected at 12 dah; for chymotrypsin at 25 dah (3.8 × 10(-3) mU mg protein(-1)), for carboxypeptidase A (280 mU mg protein(-1)) and lipase at 36 dah (480 U mg protein(-1)), for α-amylase at 7 dah (1.5 U mg protein(-1)), for acid phosphatases at 34 dah (5.5 U mg protein(-1)), and finally for alkaline phosphatase at 25 dah (70 U mg protein(-1)). The alkaline protease zymogram showed two active bands, the first (26.3 kDa) at 25 dah onwards, and the second (51.6 kDa) at 36 dah. The acid protease zymogram showed two bands (RF = 0.32 and 0.51, respectively) at 34 dah. The digestive enzymatic ontogeny of C. undecimalis is very similar to other strictly marine carnivorous fish, and we suggest that weaning process should be started at 34 dah.


Assuntos
Digestão , Hidrolases/metabolismo , Perciformes/metabolismo , Animais , Larva/enzimologia , Larva/crescimento & desenvolvimento , Perciformes/crescimento & desenvolvimento
20.
Comp Biochem Physiol C Toxicol Pharmacol ; 154(3): 187-95, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21621640

RESUMO

Biomarker responses to toxic exposure have been used for decades to indicate stress in aquatic organisms, or the magnitude of environmental pollution. However, little has been done to compare the simultaneous responses of both biochemical and physiological biomarkers. The purpose of this study was twofold. Firstly to analyse the responses of several biochemical biomarkers measured on juvenile sea bass and turbot caged in a northern France harbour at a reference and contaminated stations. Several biotransformation parameters (Ethoxyresorufin-O-deethylase - EROD - and Glutathione S-transferase -GST) and an antioxidant enzyme (Catalase -CAT) were analysed. Secondly, to compare their responses to several growth and condition indices, measured on the same fish. In the contaminated station, EROD and GST activities were found to be significantly higher, and a decrease of CAT activity was observed for both species. For individual sea bass, biochemical biomarkers showed numerous significant correlations with growth and condition indices, such as the Fulton's K condition index, the RNA:DNA ratio and the lipid storage index. On the contrary, there were only a few significant correlations for turbot, suggesting a species-specific response. Our study indicates that the analysis of the simultaneous responses of both biochemical and physiological biomarkers can be useful for monitoring complex exposure and to assess habitat quality.


Assuntos
Bass/metabolismo , Biomarcadores/metabolismo , Exposição Ambiental , Linguados/metabolismo , Fatores Etários , Animais , Antioxidantes/metabolismo , Bass/crescimento & desenvolvimento , Biomarcadores/análise , Biotransformação , Peso Corporal , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Linguados/crescimento & desenvolvimento , França , Sedimentos Geológicos/química , Glutationa Transferase/metabolismo , Metais/toxicidade , Especificidade da Espécie , Poluentes Químicos da Água/toxicidade
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