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1.
Drug Chem Toxicol ; : 1-12, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38859707

RESUMO

The herbicide triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) is already considered an environmental problem due to damage caused by incorrect disposal, leaching, and aerial dispersion, which may pose risks to the environment and human health. Studies have evaluated metabolism, absorption, excretion, and active transport but there is no clear information about its mode of action (MoA) and its cytotoxic action potential remains unknown. In this context, mitochondria have been used to assess the toxicity of xenobiotics, for this reason, to identify the toxic mechanism of triclopyr, hepatic mitochondria from Wistar rats were exposed in vitro to different concentrations of triclopyr (0.5-500 µM). There was neither formation/accumulation of reactive oxygen and nitrogen species, nor lipid peroxidation or changes in the mitochondrial antioxidant system, in addition to proper functioning of oxidative phosphorylation and ATP production. Changes were found in NAD(P)H oxidation, membrane potential dissipation and mitochondrial calcium gradient. These results demonstrate that mitochondria suffer damage related to their bioenergetics and redox status but not to their structure when exposed to concentrations of triclopyr considered higher than those described as found in the environment so far.HighlightsTriclopyr has a low mitochondrial uncoupling potential.The damage caused to the bioenergetics and redox state of the mitochondria is related to concentrations considered higher than those found in the environment.Even at high concentrations, triclopyr was not able to change the structure of the organelle after exposure.Oxidative phosphorylation and ATP production were not impaired after exposure.NAD(P)H oxidation resulted in potential membrane dissipation and mitochondrial calcium gradient dissipation.Triclopyr does not have RONS-forming properties, as well as it does not peroxide membrane lipids, it preserves membrane sulfhydryl groups and maintains the normality of the GSH/GSSG ratio.

2.
J Helminthol ; 97: e104, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38148677

RESUMO

A new species of Oswaldocruzia Travassos, 1917 (Nematoda, Molineidae), parasite of Leptodactylus macrosternum Miranda-Ribeiro, 1926 (Anura: Leptodactylidae), from Caatinga morphoclimatic domain, Brazil, is described based on morphological and molecular data. Oswaldocruzia franciscoensis n. sp. is characterised by an anterior extremity with a cephalic vesicle divided into two portions, a body covered by cuticular longitudinal ridges, and cervical alae. Males of the new species have caudal bursa of type I with a 2-1-2 pattern, spicules divided into a shoe, bifurcated fork, and blade with two unequal branches, in which the longer branch bifurcates at its distal portion end and the smaller branch with three distal processes, each with distal bifurcations. Females have didelphic and amphidelphic uteri, an ovijector divided into vestibule, anterior and posterior sphincters, and anterior and posterior infundibula. The new species differs from its Neotropical congeners that have caudal bursa of type I, based on the presence of cervical alae and by having a spicular blade distally divided into two unequal branches, with the longer branch bifurcating at its distal portion and smaller branch with three distal processes, each distally bifurcated. The partial 18S rDNA sequence generated for Oswaldocruzia franciscoensis n. sp. is the first of a representative belonging to this genus in the Neotropical region.


Assuntos
Molineoidae , Nematoides , Trichostrongyloidea , Masculino , Feminino , Animais , Anuros/parasitologia , Brasil , Nematoides/genética
3.
Cryo Letters ; 43(4): 206-221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626124

RESUMO

BACKGROUND: The proteomic profile of cryopreserved in vitro produced bovine embryos is little known but can provide insights on the successful application of cryo procedures in support of animal breeding. OBJECTIVE: To identify embryonic proteins and biomarkers related to improved cryotolerance of vitrified in vitro produced bovine embryos. MATERIALS AND METHODS: Proteins were isolated from embryo pools (n = 25 embryos per replicate) and analyzed using the nanoLC - MS/MS system. Further, the UniProtKB database (Uniprot -http://www.uniprot.org/) was used for protein identification. Proteins were classified based on their molecular mass, isoelectric point, and enzymatic activity. Post-translational modification predictions and functional gene ontology analysis were performed as well. Finally, a protein-protein interaction network was created to shed light on the embryo interactome. RESULTS: Based on the MS/MS approach, 66 proteins were identified from vitrified Bos taurus embryos. The retrieved proteins were presumably annotated, which allowed a description of the qualitative and functional aspects of the embryo proteome after the vitrification process. CONCLUSION: These findings allowed us to conclude that in vitro-produced vitrified embryos expressed proteins that underlie biological processes related to reproduction, stress and lipid metabolic process, which are essential to maintain embryo viability. doi.org/10.54680/fr22410110512.


Assuntos
Criopreservação , Fertilização in vitro , Bovinos , Animais , Fertilização in vitro/veterinária , Criopreservação/veterinária , Criopreservação/métodos , Espectrometria de Massas em Tandem , Proteômica , Vitrificação , Blastocisto , Técnicas de Cultura Embrionária/veterinária , Técnicas de Cultura Embrionária/métodos
4.
HIV Med ; 16 Suppl 1: 64-76, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25711325

RESUMO

OBJECTIVES: A proportion of HIV-positive people have condomless sex. Antiretroviral treatment (ART) reduces infectiousness, but a substantial proportion of HIV-diagnosed people are not yet on ART. We describe baseline self-reported risk behaviours in ART-naïve Strategic Timing of AntiRetroviral Treatment (START) trial participants. METHODS: All START participants completed a risk behaviour questionnaire. Data were collected on sociodemographics, lifestyle factors, health and wellbeing status and clinical status. Recent sexual behaviour and HIV transmission beliefs in the context of ART were also assessed. The primary interest was in condomless sex with serodifferent partners (CLS-D) in the past two months. RESULTS: A total of 4601 of 4685 HIV-positive participants (98%) completed the questionnaire [2559 men who have sex with men (MSM), 803 heterosexual men and 1239 women]. Region of recruitment was Europe/Israel, 33%; South America/Mexico, 25%; Africa, 22%; other, 21%. Median age was 36 years [interquartile range (IQR) 29, 44 years]. Forty-five per cent reported white ethnicity and 31% black ethnicity. Two per cent had HIV viral load < 50 HIV-1 RNA copies/mL. Seventeen per cent (767 of 4601) reported CLS-D; 20% of MSM compared with 10% of heterosexual men and 14% of women. MSM were also more likely to report multiple CLS-D partners. Possible risk limitation measures (reported by more than half of those who had CLS-D) were seropositioning (receptive anal CLS-D only) or withdrawal (insertive anal CLS-D always without ejaculation). CLS-D was more commonly reported by participants from South America/Mexico and North America compared with Europe; among heterosexual men and women CLS-D was also more commonly reported among participants from Africa compared with Europe. Knowledge of ART impact on transmission risk was low. CONCLUSIONS: A substantial minority recruited to the START study reported CLS-D at baseline. CLS-D reporting was higher in MSM than heterosexuals and varied significantly according to region of recruitment. A substantial proportion of MSM reporting CLS-D appear to take transmission risk limitation measures.


Assuntos
Transmissão de Doença Infecciosa , Infecções por HIV/transmissão , Sexo sem Proteção , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
5.
J Nanosci Nanotechnol ; 12(8): 6850-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962834

RESUMO

This paper reports on the ferromagnetic properties of aged Ti(1-x)CoxO(2-delta) anatase nanopowders with different Co contents (0.03 < or = x < or = 0.10). It is shown for the first time that aged Co:TiO2 anatase samples retain rather high values of magnetization (M), remanence (Mr) and coercivity (Hc) which provide strong evidence for a preserved long-range ferromagnetic order. Room temperature M, Mr and Hc values were measured in the ranges of [0.05, 0.79] microB/Co, [0.044, 0.096] microB/Co and [366.7,494.8]Oe, respectively, which are in the same range as in general reported either for newly prepared thin films or nanoparticles.

6.
Nat Commun ; 12(1): 4117, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226537

RESUMO

Epidemiological and clinical reports indicate that SARS-CoV-2 virulence hinges upon the triggering of an aberrant host immune response, more so than on direct virus-induced cellular damage. To elucidate the immunopathology underlying COVID-19 severity, we perform cytokine and multiplex immune profiling in COVID-19 patients. We show that hypercytokinemia in COVID-19 differs from the interferon-gamma-driven cytokine storm in macrophage activation syndrome, and is more pronounced in critical versus mild-moderate COVID-19. Systems modelling of cytokine levels paired with deep-immune profiling shows that classical monocytes drive this hyper-inflammatory phenotype and that a reduction in T-lymphocytes correlates with disease severity, with CD8+ cells being disproportionately affected. Antigen presenting machinery expression is also reduced in critical disease. Furthermore, we report that neutrophils contribute to disease severity and local tissue damage by amplification of hypercytokinemia and the formation of neutrophil extracellular traps. Together our findings suggest a myeloid-driven immunopathology, in which hyperactivated neutrophils and an ineffective adaptive immune system act as mediators of COVID-19 disease severity.


Assuntos
COVID-19/complicações , COVID-19/imunologia , Síndrome da Liberação de Citocina/complicações , Monócitos/patologia , Ativação de Neutrófilo , Idoso , Células Apresentadoras de Antígenos/imunologia , COVID-19/sangue , COVID-19/virologia , Estudos de Casos e Controles , Síndrome da Liberação de Citocina/sangue , Síndrome da Liberação de Citocina/patologia , Síndrome da Liberação de Citocina/virologia , Citocinas/sangue , Armadilhas Extracelulares/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença
7.
Genet Mol Res ; 8(4): 1481-95, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20082261

RESUMO

Physical training induces beneficial adaptations; however, exhausting exercise increases reactive oxygen species generation, resulting in damage to DNA and tissues. Pequi (Caryocar brasiliense), a fruit of the Brazilian Cerrado, contains a carotenoid-rich oil. We investigated whether pequi oil had antioxidant effects in runners. Evaluations were made after outdoor races before and after ingestion of 400 mg pequi-oil capsules for 14 days. Blood samples were taken after races and submitted to comet and TBARS assays and biochemical analyses of creatine kinase (CK), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). To determine if the protective effects of pequi-oil were influenced by antioxidant enzyme genotypes, MnSOD (-Val9Ala), CAT (-21A/T) and GPX1 (Pro198Leu) gene polymorphisms were also investigated. Pequi oil was efficient in reducing tissue injuries evaluated for AST and ALT, particularly in women, and in reducing DNA damages in both sexes. Except for CK levels, the results were influenced by MnSOD genotypes; heterozygous excess was related to less DNA damage, tissue injury and lipid peroxidation, besides presenting a better response to pequi oil against exercise-induced damage.


Assuntos
Alanina/genética , Carotenoides/análise , Dano ao DNA/efeitos dos fármacos , Dieta , Peroxidação de Lipídeos/efeitos dos fármacos , Óleos de Plantas/farmacologia , Polimorfismo Genético , Corrida , Superóxido Dismutase/genética , Valina/genética , Adolescente , Adulto , Humanos , Óleos de Plantas/química , Superóxido Dismutase/química
8.
Arch Oral Biol ; 98: 204-212, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30503976

RESUMO

The association between cardiovascular and periodontal diseases is characterized by chronic inflammatory processes, with a high prevalence worldwide and complex genetic-environment interactions. Although apolipoprotein E4 (ApoE4), one of the isoforms coded by a polymorphic APOE gene, has been widely recognized as a risk factor for cardiovascular diseases and as an immunoinflammatory factor, less is known regarding how ApoE4 affects atherosclerosis in periodontitis patients. The aim of this review was to investigate the potential underlying mechanisms related to APOE4 that could increase the risk of periodontal disease and, ultimately, of atherosclerosis. There have only been a few studies addressing apoE polymorphisms in patients with chronic periodontitis. To date, no studies have been performed that have assessed how ApoE4 affects atherosclerotic disease in chronic periodontitis patients. Although clinical studies are warranted, experimental studies have consistently documented the presence of periodontal pathogens, which are usually found in the oral cavity and saliva, in the atherosclerotic plaques of ApoE-deficient mice. In addition, in this review, the potential role of the APOE4 allele as an example of antagonistic pleiotropy during human evolution and its relation to oral health is discussed.


Assuntos
Apolipoproteínas E/metabolismo , Aterosclerose/etiologia , Doenças Periodontais/complicações , Animais , Apolipoproteína E3/metabolismo , Apolipoproteína E4 , Apolipoproteínas E/genética , Doenças Cardiovasculares/etiologia , Pleiotropia Genética , Humanos , Inflamação/etiologia , Camundongos , Microbiota , Boca , Polimorfismo Genético , Isoformas de Proteínas , Fatores de Risco
9.
Clin Microbiol Infect ; 14(1): 82-4, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17986268

RESUMO

Serotype 1 pneumococci are rarely isolated from carriers, but are an important cause of pneumococcal invasive disease in many regions of the world. This report describes the emergence and expansion of a single serotype 1 lineage (characterised by multilocus sequence type 306) among healthy carriers attending day-care centres in Portugal. The prevalence of serotype 1 strains among all pneumococci increased from 0% in 2001 and 2002, to 0.4% in 2003, and 3.1% in 2006. These observations paralleled the introduction and increased use of the seven-valent pneumococcal conjugate vaccine in the study group, suggesting a direct relationship between these events.


Assuntos
Portador Sadio/microbiologia , Vacinas Meningocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , Genótipo , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Lactente , Portugal , Análise de Sequência de DNA , Sorotipagem , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/imunologia
10.
Maturitas ; 59(1): 91-4, 2008 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-18037250

RESUMO

OBJECTIVE: The physiological role of parathormone (PTH) in the maintenance of bone mass in humans has not been fully defined. The main objective of the present study was to evaluate basal and EDTA-stimulated PTH levels in young women (Group Y=30.9 years, N=7) and in women in late menopause (Group M=64.7 years, N=7) and their relationship to bone mineral density. METHODS: The PTH secretion test was performed by induction of hypocalcemia through intravenous administration of EDTA for 2h. Blood samples were collected every 10 min and used for ionic calcium and PTH measurements. During the basal period, an additional sample was collected for the determination of osteocalcin, FSH, and estradiol. A sample of early morning second voided urine was collected for analysis of deoxypiridinoline and creatinine as well as bone mass density (BMD) was determined by dual X-ray energy absorptiometry (DEXA). RESULTS: The aged patients presented lower femoral BMD (Y=0.860 g/cm(2) vs. M=0.690 g/cm(2), p<0.01), with four of them having a T score lower than -2.5 S.D. Basal, and during the EDTA infusion, PTH values were similar in both groups. However, among aged volunteers, the rise in PTH levels was higher for subjects with normal bone mass (NM: peak=236 pg/ml) than for subjects with osteoporosis (OM: peak=134.4 pg/ml). CONCLUSIONS: The present results suggest that PTH can have a modulating effect on the rate of bone loss during late menopause.


Assuntos
Densidade Óssea , Hipocalcemia/induzido quimicamente , Menopausa , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismo , Absorciometria de Fóton , Adulto , Fatores Etários , Idoso , Ácido Edético/administração & dosagem , Feminino , Humanos , Hipocalcemia/sangue , Pessoa de Meia-Idade , Osteoporose/sangue
11.
HIV Clin Trials ; 7(2): 70-85, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16798622

RESUMO

BACKGROUND: ESPRIT, is a phase III, open-label, randomized, international clinical trial evaluating the effects of subcutaneous recombinant interleukin-2 (rIL-2) plus antiretroviral therapy (ART) versus ART alone on HIV-disease progression and death in HIV-1-infected individuals with CD4+ T-cells > or =300 cells/microL. OBJECTIVES: To describe the baseline characteristics of participants randomized to ESPRIT overall and by geographic location. METHOD: Baseline characteristics of randomized participants were summarized by region. RESULTS: 4,150 patients were enrolled in ESPRIT from 254 sites in 25 countries. 41%, 27%, 16%, 11%, and 5% were enrolled in Europe, North America, South America, Asia, and Australia, respectively. The median age was 40 years, 81% were men, and 76%, 11%, and 9% were Caucasian, Asian, and African American or African, respectively. 44% of women enrolled (n = 769) were enrolled in Thailand and Argentina. Overall, 55% and 38% of the cohort acquired HIV through male homosexual and heterosexual contact, respectively. 25% had a prior history of AIDS-defining illness; Pneumocystis jirovecii pneumonia, M. tuberculosis, and esophageal candida were most commonly reported. Median nadir and baseline CD4+ T-cell counts were 199 and 458 cells/muL, respectively. 6% and 13% were hepatitis B or C virus coinfected, respectively. Median duration of antiretroviral therapy (ART) was 4.2 years; the longest median duration was in Australia (5.2 years) and the shortest was in Asia (2.3 years). 17%, 13%, and 69% of participants began ART before 1995, between 1996 and 1997, and from 1998 onward, respectively. 86% used ART from two or more ART classes, with 49% using a protease inhibitor-based regimen and 46% using a nonnucleoside reverse transcriptase inhibitor-based regimen. 78% had plasma HIV RNA below detection (<500 cp/mL). CONCLUSION: ESPRIT has enrolled a diverse population of HIV-infected individuals including large populations of women and patients of African-American/African and Asian ethnicity often underrepresented in HIV research. As a consequence, the results of the study may have wide global applicability.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Coleta de Dados/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , HIV-1 , Interleucina-2/análogos & derivados , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Adulto , Terapia Antirretroviral de Alta Atividade , Etnicidade/estatística & dados numéricos , Feminino , Saúde Global , Infecções por HIV/complicações , Hepatite B/complicações , Hepatite C/complicações , Humanos , Injeções Subcutâneas , Interleucina-2/administração & dosagem , Interleucina-2/uso terapêutico , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Comportamento Sexual/estatística & dados numéricos , Resultado do Tratamento , Saúde da Mulher
12.
Braz J Biol ; 66(2A): 421-30, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16862295

RESUMO

Spatial and temporal density and biomass distribution of the planktonic copepods Pseudodiaptomus richardi and P. acutus along a salinity gradient were investigated in the Caeté River Estuary (North-Brazil) in June and December, 1998 (dry season) and in February and May, 1999 (rainy season). Copepod biomass was estimated using regression parameters based on the relation of dry weight and body length (prosome) of adult organisms. The Caeté River Estuary was characterized by high spatial and temporal variations in salinity (0.8-37.2). Exponential length-weight relationships were observed for both Pseudodiaptomus species. Density and biomass values oscillated between 0.28-46.18 ind. m-3 and 0.0022-0.3507 mg DW. m-3 for P. richardi; and between 0.01-17.02 ind. m-3 and 0.0005-0.7181 mg DW. m-3 for P. acutus. The results showed that the contribution of P. richardi for the secondary production in the Caeté River Estuary is more important in the limnetic zone than in other zones where euhaline-polyhaline regimes were predominant. However, it was not possible to observe a clear pattern of spatial and temporal distribution for P. acutus.


Assuntos
Biomassa , Copépodes/classificação , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional , Rios , Estações do Ano
13.
Bone Joint J ; 98-B(8): 1027-35, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27482013

RESUMO

AIMS: Using a systematic review, we investigated whether there is an increased risk of post-operative infection in patients who have received an intra-articular corticosteroid injection to the hip for osteoarthritis prior to total hip arthroplasty (THA). METHODS: Studies dealing with an intra-articular corticosteroid injection to the hip and infection following subsequent THA were identified from databases for the period between 1990 to 2013. Retrieved articles were independently assessed for their methodological quality. RESULTS: A total of nine studies met the inclusion criteria. Two recommended against a steroid injection prior to THA and seven found no risk with an injection. No prospective controlled trials were identified. Most studies were retrospective. Lack of information about the methodology was a consistent flaw. CONCLUSIONS: The literature in this area is scarce and the evidence is weak. Most studies were retrospective, and confounding factors were poorly defined or not addressed. There is thus currently insufficient evidence to conclude that an intra-articular corticosteroid injection administered prior to THA increases the rate of infection. High quality, multicentre randomised trials are needed to address this issue. Cite this article: Bone Joint J 2016;98-B:1027-35.


Assuntos
Corticosteroides/administração & dosagem , Artroplastia de Quadril/métodos , Osteoartrite do Quadril/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Corticosteroides/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Infecções por Escherichia coli/induzido quimicamente , Humanos , Injeções Intra-Articulares , Cuidados Pré-Operatórios/efeitos adversos , Cuidados Pré-Operatórios/métodos , Infecções Estafilocócicas/induzido quimicamente , Staphylococcus aureus , Infecções Estreptocócicas/induzido quimicamente
14.
Dalton Trans ; 45(31): 12301-7, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27440193

RESUMO

Single ion magnet behaviour is reported for a mononuclear Mn(iii) ion with tridentate Schiff-base ligands which exhibits a tetragonal Jahn-Teller elongation along the Namine-Mn-Namine axis and crystallises with two crystallographically distinct Mn(iii) cations (unit A and unit B). While magnetic measurements show a large and negative axial zero-field splitting (D = -4.73 cm(-1)), HF-EPR reveal two distinct large axial Ds (D = -4.60 cm(-1) for unit A and D = -4.18 cm(-1) for unit B), thus resulting in the largest D known to date for a Mn(iii) single ion magnet. AC magnetic measurements at 2000 Oe allowed determination of the energy barrier for spin reversal (10.19 K) and spin reversal relaxation time (1.476 × 10(-6) s) for the Mn(iii) ion. Computational studies were used to characterise the electronic structure and substantiate the zero field splitting in the Mn(iii) complex.

15.
Braz J Med Biol Res ; 38(6): 901-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15933784

RESUMO

Mercury is a xenobiotic metal that is a highly deleterious environmental pollutant. The biotransformation of mercury chloride (HgCl2) into methylmercury chloride (CH3HgCl) in aquatic environments is well-known and humans are exposed by consumption of contaminated fish, shellfish and algae. The objective of the present study was to determine the changes induced in vitro by two mercury compounds (HgCl2 and CH3HgCl) in cultured human lymphocytes. Short-term human leukocyte cultures from 10 healthy donors (5 females and 5 males) were set-up by adding drops of whole blood in complete medium. Cultures were separately and simultaneously treated with low doses (0.1 to 1000 microg/l) of HgCl2 and CH3HgCl and incubated at 37 degrees C for 48 h. Genotoxicity was assessed by chromosome aberrations and polyploid cells. Mitotic index was used as a measure of cytotoxicity. A significant increase (P < 0.05) in the relative frequency of chromosome aberrations was observed for all concentrations of CH3HgCl when compared to control, whether alone or in an evident sinergistic combination with HgCl2. The frequency of polyploid cells was also significantly increased (P < 0.05) when compared to control after exposure to all concentrations of CH3HgCl alone or in combination with HgCl2. CH3HgCl significantly decreased (P < 0.05) the mitotic index at 100 and 1000 microg/l alone, and at 1, 10, 100, and 1000 microg/l when combined with HgCl2, showing a synergistic cytotoxic effect. Our data showed that low concentrations of CH3HgCl might be cytotoxic/genotoxic. Such effects may indicate early cellular changes with possible biological consequences and should be considered in the preliminary evaluation of the risks of populations exposed in vivo to low doses of mercury.


Assuntos
Linfócitos/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Feminino , Humanos , Masculino , Índice Mitótico , Testes de Mutagenicidade
16.
Dalton Trans ; 44(3): 1264-72, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25415492

RESUMO

The magnetic properties of two similar Er(3+) complexes have been investigated. [Er(tpm)3(bipy)] (Htpm = 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione and bipy = 2,2'-bipyridine) displays thermally activated slow relaxation of magnetisation under a zero direct-current (DC) field. Under an applied HDC field of 1000 G, [Er(tpm)3(bipy)] exhibits two thermally activated processes with energy barriers of 9 and 40 K, while [Er(tfa)3(bipy)] (Htfa = 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione) shows only one activated process with a barrier of 15 K. Both compounds are luminescent in the solid state, emitting in the near IR region.

17.
Avian Pathol ; 30(3): 209-14, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19184902

RESUMO

An investigation on the digenetic trematodes parasitizing free range reared guinea fowls was conducted in the state of Rio de Janeiro, Brazil, based on clinical examination, necropsies and histopathological findings in 36 guinea fowls. Parasites, prevalence and intensity of infection were, respectively: Paratanaisia bragai, 61.1% and 31 (in each kidney); Athesmia heterolecithodes, 8.3% and 38; Conspicuum conspicuum, 2.8% and 1. A. heterolecithodes was highly pathogenic to guinea fowls, causing severe hepatic lesions. However, C. conspicuum and P. bragai were less pathogenic in the considered intensities of infection. This is the first time that these parasite species have been reported in Brazilian guinea fowls.

18.
Arq Neuropsiquiatr ; 53(4): 837-40, 1995 Dec.
Artigo em Português | MEDLINE | ID: mdl-8729785

RESUMO

A case of chondromyxoid fibroma (CMF) arising from the 5th right costovertebral junction and spreading into spinal canal causing spinal cord compression is presented. A myelotomography revealed a complete block at T5 level. The patient underwent a decompressive laminectomy with removal of an epidural tumor. This specimen was sent for pathological examination and interpreted as a CMF. The patient had a neurological improvement, post operative MRI revealed a spinal cord free of compression, and we decided on the follow up of the case. Two years later there was recurrence of the tumor. A posterolateral access by costotransversectomy was made and the lesion was resected. The patient had a neurological improvement which persists on the follow up (two years, at present). Clinical, radiologic and histologic findings, surgical management and recurrence are discussed. The pertinent literature is reviewed.


Assuntos
Condroblastoma/complicações , Compressão da Medula Espinal/etiologia , Neoplasias da Medula Espinal/complicações , Adulto , Condroblastoma/cirurgia , Feminino , Seguimentos , Humanos , Laminectomia , Neoplasias da Medula Espinal/cirurgia
19.
Arq Gastroenterol ; 25(4): 193-7, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3268075

RESUMO

An endoscopic manometric technique was used to determine the CBD-duodenum junction pressure profile before and immediately after endoscopic sphincterotomy in 13 patients with common bile duct stones. Premedication (meperidine, atropine, and diazepam) was given to all patients and endoscopic retrograde cholangiopancreatography was performed before endoscopic sphincterotomy. In the patients with intact papilla the features of the sphincter of Oddi motility were similar to those previously described for patients not given premedication or submitted to cholangiography before endoscopic sphincterotomy. Endoscopic sphincterotomy which was successful for immediate stone removal in 9 of 13 patients caused an immediate reduction of sphincter of Oddi motility in all patients, but abolished it in only 2 of them. The present results show that successful common bile duct stone extraction by means of endoscopic sphincterotomy can be accomplished without total abolition of sphincter of Oddi motility.


Assuntos
Ampola Hepatopancreática/cirurgia , Colangiopancreatografia Retrógrada Endoscópica , Ducto Colédoco/fisiopatologia , Cálculos Biliares/cirurgia , Esfíncter da Ampola Hepatopancreática/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Pressão
20.
Dalton Trans ; 43(18): 6752-61, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24643638

RESUMO

Erbium complexes featuring ß-diketonate ligand 2,4-hexanedione (Hh) and N,N-donor-ligands 2,2'-bipyridine (bipy), 5-nitro-1,10-phenanthroline (5NO2phen) and bathophenanthroline (bath) have been synthesized. The structures of the ternary complexes [Er(h)3(bipy)], [Er(h)3(5NO2phen)] and [Er(h)3(bath)] have been determined by single crystal X-ray diffraction. Excitation of the complexes in the ultraviolet region (337 nm) led to near infrared (NIR) luminescence at 1532 nm characteristic of the trivalent erbium ion in the three compounds, with an improved antenna effect in the 5-nitro-1,10-phenanthroline complex. The AC susceptibility studies conducted at frequencies ranging from 33 to 9995 Hz and at temperatures in the 1.7 to 10 K range revealed that the application of a static magnetic field induces a slow magnetic relaxation in all three compounds. The complex with the bulkier capping ligand (bathophenanthroline) exhibits the highest energy barrier U/k(B) = 23 K.

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