Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Adv Exp Med Biol ; 1062: 361-371, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29845545

RESUMO

The literature on sero-epidemiological studies of flaviviral infections in the African continent is quite scarce. Much of the viral epidemiology studies have been focussing on diseases such as HIV/AIDS because of their sheer magnitude and impact on the lives of people in the various affected countries. Increasingly disease outbreaks caused by arboviruses such as the recent cases of chikungunya virus, dengue virus and yellow fever virus have prompted renewed interest in studying these viruses. International agencies from the US, several EU nations and China are starting to build collaborations to build capacity in many African countries together with established institutions to conduct these studies. The Tofo Advanced Study Week (TASW) was established to bring the best scientists from the world to the tiny seaside town of Praia do Tofo to rub shoulders with African virologists and discuss cutting-edge science and listen to the work of researchers in the field. In 2015 the 1st TASW focussed on Ebola virus. The collections of abstracts from participants at the 2nd TASW which focused on Dengue and Zika virus as well as presentations on other arboviruses are collated in this chapter.


Assuntos
Infecções por Arbovirus/epidemiologia , Arbovírus/isolamento & purificação , África/epidemiologia , Animais , Anticorpos Antivirais/sangue , Infecções por Arbovirus/sangue , Infecções por Arbovirus/virologia , Arbovírus/genética , Arbovírus/imunologia , Humanos , Estudos Soroepidemiológicos
2.
Sci Rep ; 12(1): 10262, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715474

RESUMO

Limited information is available about the effect of mid-pregnancy viral infections on the placental expression of efflux transporters and offspring behavior. We hypothesized that maternal exposure to polyinosinic-polycytidylic acid [poly(I:C)], a synthetic double-stranded RNA viral mimic, would impair placental cell turnover, the expression of selected ABC transporters and adult offspring behavior. C57BL/6 mice were administered poly(I:C) (10 mg/Kg;ip) or vehicle at gestational day (GD) 13.5 (mid-pregnancy). Dams were euthanized for blood collection 4 h after injection, fetal and placental collection at GD18.5 or allowed to deliver spontaneously at term. At GD 13.5, poly(I:C) induced an acute pro-inflammatory response characterized by an increase in maternal plasma levels of IL-6, CXCL-1 and CCL-2/MCP-1. At GD 18.5, poly(I:C) decreased cell proliferation/death in the labyrinthine and increased cell death in the junctional zones, characterizing a disruption of placental cell turnover. Abca1 and Abcg1 immunolabelling was decreased in the labyrinthine zone, whereas Abca1, Abcg1 and breast cancer resistance transporter (Bcrp) expression increased in the junctional zone. Moreover, adult offspring showed motor and cognitive impairments in the Rotarod and T-water maze tests. These results indicate that viral infection during mid-pregnancy may disrupt relevant placental efflux transporters, as well as placental cell turnover and offspring behavior in adult life.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Disfunção Cognitiva , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Disfunção Cognitiva/metabolismo , Feminino , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Placenta/metabolismo , Poli I-C/farmacologia , Gravidez
3.
Eur Eat Disord Rev ; 18(1): 58-66, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20054878

RESUMO

PURPOSE: The impact of weight on quality of life (IWQOL-Lite) is a self-administered instrument that assesses quality of life in obesity. It is composed of 31 items and five domains (physical function, self-esteem, sexual life, public distress, and work). The aim of the present study was to evaluate reliability (test-retest), internal structure, construct validity and discriminant validity. METHODS: IWQOL-Lite scores were obtained from 89 people in a Weight Watchers institution (clinical sample) and 156 community volunteers (community sample). The participants were selected based on the same criteria: gender (female) and age (> 24 years), except for BMI. The community sample also completed the SF-36, a generic measure of health-related quality of life. RESULTS: The Brazilian IWQOL-Lite demonstrated good test-retest reliability, internal consistency, discriminative validity and convergent validity. CONCLUSIONS: The IWQOL-Lite is the first specific instrument validated in Brazil for assessing quality of life in obesity. The results reveal that IWQOL-Lite is an instrument with good psychometric properties. Nevertheless, in some cases results were dissimilar to those reported in earlier studies using the original American English.


Assuntos
Inquéritos Epidemiológicos , Obesidade/psicologia , Psicometria/normas , Qualidade de Vida/psicologia , Inquéritos e Questionários/normas , Adulto , Brasil , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Seleção de Pacientes , Reprodutibilidade dos Testes , Autoimagem
4.
Rev Port Cir Cardiotorac Vasc ; 17(2): 109-13, 2010.
Artigo em Português | MEDLINE | ID: mdl-21298123

RESUMO

Traditional open repair of aortic arch aneurysms is a complex and demanding surgery that requires cardiopulmonary bypass, hypothermia and circulatory arrest, being associated with considerable morbidity and mortality. Even with significant advances in pre-operative assessment and optimization, advanced anaesthetic techniques and intensive care, conventional aortic arch repairs remain amongst the highest risk of across all surgical specialties. Therefore, a hybrid approach with sequential transposition of the supra-aortic branches and endovascular stent-graft placement is a less invasive alternative treatment that opens the indication for repair to more critical patients. We report our institution's first experience in the hybrid surgery of aortic arch aneurysms.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Vasculares/métodos
5.
Reprod Toxicol ; 98: 82-91, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32916274

RESUMO

Bacterial infection alters placental ABC transporters expression. These transporters provide fetal protection against circulating xenobiotics and environmental toxins present in maternal blood. We hypothesized that lipopolysaccharide (LPS-bacterial mimic) alters the yolk sac morphology and expression of key ABC transporters in a gestational-age dependent manner. Yolk sac samples from C57BL/6 mice were obtained at gestational ages (GD) 15.5 and GD18.5, 4 or 24 h after LPS exposure (150ug/kg; n = 8/group). Samples underwent morphometrical, qPCR and immunohistochemistry analysis. The volumetric proportions of the histological components of the yolk sac did not change in response to LPS. LPS increased Abcg2 expression at GD15.5, after 4 h of treatment (p < 0.05). No changes in Abca1, Abcb1a/b, Abcg1, Glut1, Snat1, Il-1ß, Ccl2 and Mif were observed. Il-6 and Cxcl1 were undetectable in the yolk sac throughout pregnancy. Abca1, breast cancer resistance protein (Bcrp, encoded by Abcg2) and P-glycoprotein (P-gp/ Abcb1a/b) were localized in the endodermal (uterine-facing) epithelium and to a lesser extent in the mesothelium (amnion-facing), whereas Abca1 was also localized to the endothelium of the yolk sac blood vessels. LPS increased the labeling area and intensity of Bcrp in the yolk sac's mesothelial cells at GD15.5 (4 h), whereas at GD18.5, the area of Bcrp labeling in the mesothelium (4 and 24 h) was decreased (p < 0.05). Bacterial infection has the potential to change yolk sac barrier function by affecting Bcrp and Abcg2 expression in a gestational-age dependent-manner. These changes may alter fetal exposure to xenobiotics and toxic substances present in the maternal circulation and in the uterine cavity.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Lipopolissacarídeos/farmacologia , Saco Vitelino/efeitos dos fármacos , Animais , Feminino , Idade Gestacional , Camundongos Endogâmicos C57BL , Gravidez , Saco Vitelino/metabolismo
6.
Sci Rep ; 9(1): 11488, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391498

RESUMO

Malaria in Pregnancy (MiP) is characterized by placental accumulation of Plasmodium-infected erythrocytes, intrauterine growth restriction (IUGR) and preterm delivery (PTD). Placental ATP-binding cassette (ABC) transporters mediate the efflux of nutrients, cytokines and xenobiotics. The expression and activity of these transporters are highly responsive to infection. We hypothesized that MiP would perturb the expression of placental ABC transporters, promoting PTD. Peripheral blood, spleens, livers and placentas of pregnant mice, infected with Plasmodium berghei ANKA on gestational day (GD) 13.5, were collected and analyzed on GD18.5. The primary consequences of human MiP, including IUGR, PTD (20%) and placental inflammation, were recapitulated in our mouse model. Electron microscopy revealed attenuated presence of labyrinthine microvilli and dilated spongiotrophoblasts -granular endoplasmic reticulum cisternae. Additionally, a decrease in placental Abca1 (ABCA1), Abcb1b (P-glycoprotein), Abcb9 and Abcg2 (BCRP) expression was observed in MiP mice. In conclusion, MiP associated with PTD impairs placental ABC transporters' expression, potentially modulating placental nutrient, environmental toxin and xenobiotic biodistribution within the fetal compartment, and may, at some degree, be involved with pregnancy outcome in MiP.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Malária/complicações , Trabalho de Parto Prematuro/imunologia , Placenta/patologia , Plasmodium berghei/imunologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Malária/imunologia , Malária/parasitologia , Troca Materno-Fetal/imunologia , Camundongos , Nutrientes/metabolismo , Trabalho de Parto Prematuro/parasitologia , Trabalho de Parto Prematuro/patologia , Placenta/metabolismo , Gravidez , Xenobióticos/metabolismo
7.
Int J Cosmet Sci ; 28(2): 95-101, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18492143

RESUMO

A new method for high-resolution analyses of hair surface charge density under ambient conditions is presented in this paper. Electrostatic force microscopy (EFM) is used here to analyze changes in surface charge density in virgin hair, bleached hair, and hair treated with a cationic polymer. The atomic force microscopy technique is used concomitantly to analyze morphological changes in hair roughness and thickness. The EFM images depict exactly how the polymer is distributed on the surface of the hair fiber. The EFM's powerful analytical tools enabled us to evaluate the varying degrees of interaction between the hair fiber surface charge density and the cationic polymer. The surface charge density and the polymer's distribution in the hair fibers are presented in the light of EFM measurements.

8.
Braz J Med Biol Res ; 38(2): 215-20, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15785832

RESUMO

Gastroesophageal reflux (GER) disorder was studied in children and adolescents with chronic and/or recurrent rhinosinusitis not associated with bronchial asthma. Ten children with a clinical and radiological diagnosis of chronic and/or recurrent rhinosinusitis, consecutively attended at the Pediatric Otolaryngology Outpatient Clinic, Federal University of São Paulo, were evaluated. Prolonged esophageal pH monitoring was used to investigate GER disorder. The mean age of the ten patients evaluated (eight males) was 7.4 +/- 2.4 years. Two patients presented vomiting as a clinical manifestation and one patient presented retrosternal pain with a burning sensation. Twenty-four-hour esophageal pH monitoring was performed using the Sandhill apparatus. An antimony probe electrode was placed in the lower third of the esophagus, confirmed by fluoroscopy and later by a chest X-ray. The parameters analyzed by esophageal pH monitoring included: total percent time of the presence of acid esophageal pH, i.e., pH below 4 (<4.2%); total number of acid episodes (<50 episodes); number of reflux episodes longer than 5 min (3 or less), and duration of the longest reflux episode (<9.2 min). One patient (1/10, 10%) presented a 24-h esophageal pH profile compatible with GER disorder. This data suggest that an association between chronic rhinosinusitis not associated with bronchial asthma and GER disorder may exist in children and adolescents, especially in those with compatible GER disorder symptoms. In these cases, 24-h esophageal pH monitoring should be performed before indicating surgery, since the present data suggest that 10% of chronic rhinosinusitis surgeries can be eliminated.


Assuntos
Refluxo Gastroesofágico/etiologia , Rinite/complicações , Sinusite/complicações , Criança , Pré-Escolar , Doença Crônica , Feminino , Refluxo Gastroesofágico/diagnóstico , Humanos , Concentração de Íons de Hidrogênio , Masculino , Recidiva
9.
Mol Biochem Parasitol ; 117(2): 169-77, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606227

RESUMO

We isolated a gene that is differentially expressed during Trypanosoma cruzi metacyclogenesis by the representation of differential expression (RDE) method, using differentiating epimastigotes cultured in chemically defined medium. This gene, the metacyclogenin gene, encodes a 630-nucleotide mRNA that is specifically associated with the polysomes of epimastigotes allowed to differentiate for 24 h. We sequenced and characterized the metacyclogenin gene and found that there were at least three copies of the gene organized into tandem 2.8 kb repeats in the genome of T. cruzi Dm28c. We analyzed the repeats and found that they contained two other genes, one encoding tryparedoxin peroxidase and the other encoding a 0.6 kb mRNA (named associated gene or AG) with sequences showing no significant similarity to those in the GenBank database. Northern blot analysis of polysomal RNA extracted from replicating and differentiating epimastigotes showed that metacyclogenin and AG genes displayed similar patterns of expression. Their products were detected only in differentiating epimastigotes, whereas tryparedoxin peroxidase was detected only in the polysomal RNA fraction of replicating and differentiating epimastigotes. In Northern blots of total RNA from differentiating and replicating epimastigotes, the genes studied were detected in both cell populations. The differential expression of the metacyclogenin gene was confirmed by immunocytochemistry studies showing that the protein is detected only in differentiating (adhered) epimastigote. The results suggest that mRNA mobilization to polysomes is an important mechanism in the regulation of gene expression in T. cruzi.


Assuntos
Clonagem Molecular/métodos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Protozoários/genética , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/metabolismo , Sequência de Aminoácidos , Animais , Meios de Cultura , DNA Complementar/genética , Genoma de Protozoário , Estágios do Ciclo de Vida , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Análise de Sequência de DNA , Trypanosoma cruzi/genética
10.
FEMS Microbiol Lett ; 164(2): 323-7, 1998 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9682481

RESUMO

Tachyzoites of Toxoplasma gondii are able to infect several cell types tested (wild-type chinese hamster ovary (CHO) cells and glycosylation mutants, Vero and LLCMK2 cells). However, the extent of infection varied. Mutant cells which present few or no surface-exposed sialic acid residues were infected to a lower extent. Similar results were obtained if sialic acid residues were removed by previous neuraminidase treatment. Addition of sialic acid residues to surface-exposed glycoconjugates using fetuin as a sialic acid donor and the trans-sialidase of Trypanosoma cruzi rendered the cells more easily infected by Toxoplasma gondii. These observations indicate that surface-exposed carbohydrate residues of the host cell are involved on the process of Toxoplasma gondii-host cell recognition.


Assuntos
Ácido N-Acetilneuramínico/fisiologia , Toxoplasma/patogenicidade , Animais , Células CHO , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Glicosilação , Interações Hospedeiro-Parasita , Ácidos Neuramínicos/metabolismo , Toxoplasma/crescimento & desenvolvimento , Células Vero
11.
J Cosmet Sci ; 54(3): 271-81, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12858226

RESUMO

A new method for morphological hair analysis at high resolution and under ambient conditions is presented in this paper. The AFM has been used in these experiments to analyze morphological changes in hair roughness and thickness after UV radiation. Through the powerful analytical AFM tools, changes in hair morphology can be proven. A new quantitative methodology to evaluate hair structure is presented in this paper.


Assuntos
Cabelo/efeitos da radiação , Microscopia de Força Atômica , Raios Ultravioleta , Cabelo/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Propriedades de Superfície
12.
Rev Port Cardiol ; 15(5): 379-84, 363-4, 1996 May.
Artigo em Português | MEDLINE | ID: mdl-8763512

RESUMO

Between August 1992 and July 1995 five patients with cardiac free wall rupture after acute myocardial infarction underwent surgical treatment in Centro de Cirurgia Torácica do Hospital de S. João. The diagnosis was suggested by the hemodynamic changes and in four patients confirmed with echocardiography and pericardiocentesis. All patients survived and were discharged from the hospital. Medical treatment with inotropic drugs, pericardiocentesis and intraaortic balloon counterpulsation allows hemodynamic stabilization but only early surgery may assure survival.


Assuntos
Ruptura Cardíaca Pós-Infarto/cirurgia , Adulto , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Ruptura Cardíaca Pós-Infarto/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
13.
Rev Port Cardiol ; 11(11): 929-32, 1992 Nov.
Artigo em Português | MEDLINE | ID: mdl-1290640

RESUMO

STUDY OBJECTIVE: To determine the arterial compliance through the evaluation of pulse wave velocity. DESIGN: Open study with direct comparison of different groups within a 12 week evaluation period. PATIENTS: 69 patients, 49 with hypertension and 20 normals individuals. INTERVENTIONS: Different groups with the following treatments: Isradipine, Lisinopril, Dilevalol and no therapy. MEASUREMENTS AND MAIN RESULTS: There is marked differences in the pulse wave velocity when hypertensive patients are compared with normal individuals (p < 0.001). In a 12 week therapeutic evaluation there is an improvement in the pulse wave velocity particularly when the arterial pressure was lowered to normal values in the hypertensive patients: Lisinopril (p < 0.005), Isradipine (p < 0.005), Dilevalol (p < 0.025). CONCLUSIONS: It is very easy to evaluate the pulse wave velocity. Arterial compliance, which may be evaluated using the pulse wave velocity, is significantly reduced in hypertensive patients, compared with age-matched control subjects. The use of antihypertensive drugs is associated with changes in arterial compliance. There is a significant decrease in the pulse wave velocity after the administration of ACE inhibitors, calcium channel blockers and beta blockers for an equivalent fall in blood pressure. These observations emphasizes the potential importance of the changes in the large arteries, considered as either an associated factor or a consequence of elevated blood pressure, in the evaluation of the cardiovascular morbidity, and mortality of patients treated for hypertension.


Assuntos
Hipertensão/fisiopatologia , Pulso Arterial , Adulto , Artérias/fisiopatologia , Complacência (Medida de Distensibilidade) , Humanos , Pessoa de Meia-Idade
14.
Rev Port Cardiol ; 10(2): 121-4, 1991 Feb.
Artigo em Português | MEDLINE | ID: mdl-2059468

RESUMO

OBJECTIVE: Determination of left ventricular function, in patients with ventricular inhibited (VVI) and atrioventricular universal (DDD) pacemakers, by measurement of systolic time intervals. DESIGN: Twenty six patients were studied (six with DDD pacemakers and twenty with VVI pacemakers). In all of them systolic time intervals measurements were obtained the day before and one week after the implant. PATIENTS: We have studied twenty six patients consecutively, and all of them completed the study. INTERVENTIONS: The measurement of systolic time intervals was obtained, by the simultaneous recording of ECG, phonocardiogram and carotid arterial pulse. The recordings were obtained at a paper speed of 100 mm/sec. MEASUREMENTS AND RESULTS: The values obtained before the implantation were similar in both groups, but one week after implantation they show a closer to normal ventricular function, in patients with DDD pacemakers. CONCLUSIONS: The measurements of systolic time intervals, is a very easy method, to determine left ventricular function non invasively. In patients with DDD pacemakers, the left ventricular function, was better than in patients with VVI pacemakers.


Assuntos
Marca-Passo Artificial , Função Ventricular Esquerda , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole
15.
Rev Port Cardiol ; 8(5): 367-70, 1989 May.
Artigo em Português | MEDLINE | ID: mdl-2631848

RESUMO

OBJECTIVE: To evaluate changes on left ventricular function as assessed by systolic time intervals (STI), by programming "physiological" pacemakers either on VVI or DDD mode. STUDY DESIGN: Comparison of STI values--electromechanical systole (QS2); left ventricular ejection time (LVET); pre-ejection period (PEP); PEP/LVET--in patients submitted to double chamber pacing programmed in DDD or VVI mode. SETTING: Cardiac Pacing Center in a Department of Cardiology at a University Hospital. PATIENTS: We have studied 12 patients (3 men, 9 women), mean age 56.16 years (range 25-76 years) treated with double chamber pacing. INTERVENTIONS: Initial measurements of STI in DDD or one week in VVI mode, and again after one week in DDD mode. RESULTS: Significant changes were found after the first week in VVI pacing, versus baseline determination in DDD pacing, for LVET, PEP, and PEP/LVET (p less than 0.05). At the end of the second week (DDD pacing), there were also statistically significant differences for QS2 (P less than 0.05), LVET (P less than 0.01) and PEP/LVET (P less than 0.05) values when compared with the ones obtained in VVI pacing, at the end of the preceding week. No significant changes were found between the initial and the final STI determinations (both in DDD pacing). CONCLUSION: We concluded for a better performance of the left ventricle at rest when "physiological" pacing is compared with VVI pacing.


Assuntos
Bloqueio Cardíaco/fisiopatologia , Contração Miocárdica/fisiologia , Marca-Passo Artificial , Volume Sistólico/fisiologia , Sístole/fisiologia , Adulto , Idoso , Feminino , Bloqueio Cardíaco/terapia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Rev Port Cardiol ; 10(10): 737-40, 1991 Oct.
Artigo em Português | MEDLINE | ID: mdl-1781991

RESUMO

OBJECTIVE: to evaluate the performance of a new ball valve prosthesis. DESIGN: set up of two groups of patients who underwent mitral valve replacement with two different prosthesis: the Macchi prosthesis under evaluation and the well known Starr-Edwards model prosthesis. The chi-square test was used to compare the results. PATIENTS: Patients referred for valvular surgery. INTERVENTIONS: One group of 98 consecutive patients who underwent isolated mitral valve replacement with a Macchi prosthesis from January 1984 to June 30 1986 was compared to a matched group of 49 patients who received a Starr-Edwards prosthesis in the same period of time. Follow-up data were available from 99% patients in the Macchi group 96% in the Starr-Edwards group, with a mean follow-up time of 35.2 (2-57) and 42.9 (4-62) months, respectively. RESULTS: There was no statistical difference in the incidence per 100 patients--month of prosthetic complications--thromboembolism, hemorrhagic events, prosthetic endocarditis, reoperation and mechanical failure. CONCLUSIONS: In our experience and with the available follow-up data the Macchi prosthesis is a good cost effective option when there is indication for a ball valve prosthesis.


Assuntos
Próteses Valvulares Cardíacas , Adulto , Estudos de Avaliação como Assunto , Seguimentos , Próteses Valvulares Cardíacas/efeitos adversos , Próteses Valvulares Cardíacas/mortalidade , Humanos , Desenho de Prótese , Taxa de Sobrevida
17.
Rev Bras Enferm ; 54(2): 268-70, 2001.
Artigo em Português | MEDLINE | ID: mdl-12240654

RESUMO

This article outlines the trajectory of the Brazilian Association of Nursing (ABEn) in Alagoas and its influence in the organization of the nursing profession in this federal state. It points out that ABEn-AL was the first institution to organize nursing in Alagoas, since it was founded prior to any nursing graduation course or even any nursing syndicate. Therefore, ABEn is considered a decisive landmark in the political and professional organization of nursing in the state of Alagoas.


Assuntos
Sociedades de Enfermagem/história , Brasil , História do Século XX , Sociedades de Enfermagem/organização & administração
18.
Aquat Toxicol ; 104(3-4): 291-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21652016

RESUMO

In the present study, in vivo and in vitro exposures were used to assess the genotoxicity of lead (Pb) to the freshwater fish Prochilodus lineatus. The comet assay using blood, liver and gill cells, and the occurrence of micronuclei (MN) and other erythrocytic nuclear abnormalities (ENA) were used to assess the genotoxic potential of lead in vivo. Metallothionein content (MT) was measured in fish liver in order to evaluate the protection of fish against Pb toxicity. Fish erythrocytes were exposed to Pb in vitro (1, 3 and 6 h) and the number of viable cells, DNA integrity, using the comet assay, and lysosomal membrane stability, measured by the neutral red retention assay (NRRA) were analyzed. The results of the comet assay after in vivo toxicity tests (6, 24 and 96 h) showed that Pb was genotoxic for all the three tissues analyzed after 96 h exposure. A significant increase in liver MT content was observed after 6 and 24 h of Pb exposure. MN frequency did not increase after Pb exposures, but the frequency of the other ENA, such as kidney-shaped nuclei, segmented nuclei and lobed nuclei, showed a significant increase after 24 and 96 h, indicating that ENA is a better biomarker for Pb exposure than MN alone after short-term exposures. The results of the comet assay performed with erythrocytes in vitro exposed to lead confirmed its genotoxic effect and showed that DNA damage increased with increasing exposure time. Moreover, the NRRA clearly indicated that Pb induces a destabilization of the lysosomal membrane. These results demonstrate the potential genotoxicity and cytotoxicity of lead after acute exposures.


Assuntos
Peixes/fisiologia , Chumbo/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Monitoramento Ambiental , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Água Doce/química , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Chumbo/análise , Chumbo/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Metalotioneína/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA