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1.
Braz J Biol ; 83: e276585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126641

RESUMO

Strategies for flood control associated to extreme precipitation events in urban areas are urgent, in order to prevent not only material damages but also to avoid human losses. The construction of flood contention reservoirs ("piscinões") has become a common engineering intervention in urban and peri-urban areas. However, there is a lack of studies focused on the evaluation of environmental impacts of this type of construction. This study intended to verify the ecological effects of a retention reservoir built directly on the course of the Cascata stream, Botucatu (SP). Three sampling sites were selected, located upstream the reservoir, in the reservoir and downstream. Samplings were carried out in July (winter - dry) and November (late spring - rainy) 2020. In situ measurements were obtained through a multiparameter probe (temperature, pH, electrical conductivity, dissolved oxygen, total dissolved solids, and oxidation-reduction potential) and water samples were collected for laboratory determinations (nitrogen, total phosphorus, thermotolerant coliforms, and chlorophyll-a). For fish sampling, manual trawls, sieves and hand nets were used, with a sampling effort of 10 throws per artefact and site. Despite the small distance between the sampling points (~1,300 m) considerable changes in the limnological conditions and fish community structure were observed. The studied environment is originally a small river surrounded by riparian forest, but this characteristic was abruptly changed in the reservoir stretch, with the direct exposition of a much larger water surface to intense solar radiation and atmosphere exchanges. Consequently, as evidenced by the PCA analysis, there was a considerable (stream-reservoir increase) of temperature, dissolved oxygen and chlorophyll. However, this spatial trend was partially disturbed by an accidental sewage-pipe rupture (posteriorly fixed) adjacent to the first sampling point, due to a previous event of extreme precipitation, which resulted in increased values of nutrients, chlorophyll, conductivity and thermotolerant coliforms. Eleven fish species were collected (two non-native), belonging to seven families and five orders. The upstream reference point (despite not be pristine), was characterized by the predominance of native species, while the reservoir condition favored the development of large populations of the non-native species. Despite the urgency of effective actions to prevent floods in urban areas, construction of contention reservoirs directly on stream courses should be avoided, due to their negative ecological impacts.


Assuntos
Monitoramento Ambiental , Inundações , Animais , Humanos , Monitoramento Ambiental/métodos , Brasil , Clorofila , Água , Limnologia , Oxigênio/análise
2.
J Mol Evol ; 90(2): 176-181, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35195749

RESUMO

To perform a quasispecies assessment of the effect of vaccine combinations and antibody titers on the emergence of Avian coronavirus (AvCoV) escape mutants, 5-week-old males from a commercial chicken breeder lineage were vaccinated intramuscularly with one dose of a monovalent (genotype GI-1) or a bivalent (genotypes GI-1 and GI-11 (n = 40 birds/group) AvCoV vaccine. Seven birds were kept as controls. Six weeks later, pools of sera of each group were prepared and incubated at virus neutralization doses of 10 and 10-1 with the Beaudette strain (GI-1) of AvCoV in VERO cells. Rescued viruses were then submitted to genome-wide deep sequencing for subconsensus variant detection. After treatment with serum from birds vaccinated with the bivalent vaccine at a titer of 10-1, an F307I variant was detected in the spike glycoprotein that mapped to an important neutralizing region, which indicated an escape mutant derived from natural selection. Further variants were detected in nonstructural proteins and non-coding regions that are not targets of neutralizing antibodies and might be indicators of genetic drift. These results indicate that the evolution of AvCoV escape mutants after vaccination depends on the type of vaccine strain and the antibody titer and must be assessed based on quasispecies rather than consensus dominant sequences only because quasispecies may be otherwise undetected.


Assuntos
Gammacoronavirus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Galinhas , Chlorocebus aethiops , Glicoproteína da Espícula de Coronavírus/genética , Células Vero
3.
Heliyon ; 6(7): e04381, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32665984

RESUMO

Alphacoronavirus 1 (subgenus Tegacovirus, genus Alphacoronavirus, family Coronaviridae), which encompasses transmissible gastroenteritis virus (TGEV), feline coronavirus (FCoV) and canine coronavirus (CCoV), is an important pathogen that can cause severe gastroenteritis and is distributed worldwide. CCoV has two different genotypes: CCoV type I, which has a high identity with FCoV-I, and CCoV type II, which is divided into two subtypes, CCoV IIa (pantropic) and CCoV IIb, which is related to FCoV-II and has been involved in multiple recombination events. Between 2014 and 2018, 43 fecal samples from puppies and young dogs under 1 year of age with hemorrhagic enteritis and from 5 cats under 2 years of age with ascites or thoracic effusion were collected by a private veterinary practice in Bogotá, Colombia. A screening for Coronavirus via RT-PCR (nsp12) and PCR amplification of Canine protoparvovirus (VP1) revealed 27.1% (13/49) and 72.9% (35/49) positive samples, respectively. Positive samples for coronavirus were tested for M, N, S and the sequences grouped in the FCoV, CCoV-I and CCoV-IIb clusters that were distant from the pantropic type (IIa). The N gene formed two clusters, one exclusively with samples from this study in subtype II and another with strains in subtype I. For gene S (subtype I), the samples clustered with the Brazilian samples, while samples positive for S subtype IIb grouped into a cluster distinct from the other reference sequences. The prevalence of coronaviruses identified in this study is within the range reported by different countries worldwide.

4.
J Ethnopharmacol ; 222: 177-189, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29689352

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Myracrodruon urundeuva Allemão (Aroeira-do-Sertão), Anacardiaceae, is one of the most used plants in folk medicine in Northeastern Brazil as an anti-inflammatory, healing and antiulcer. This species is threatened with extinction due to anthropogenic exploitation. The importance of this study is to demonstrate the feasibility of a conservationist model of replacement of the M. urundeuva adult tree (inner bark) for its under developing plants (shoots) in order to ensure the preservation of this species, but also to ensure sufficient raw material for pharmaceutical purposes. AIM OF THE STUDY: To characterize chemically and assess the gastroprotective and anti-inflammatory activities of the fluid extracts from M. urundeuva innebark (adult plant) as well as stem and leaves of shoots (young plant). MATERIALS AND METHODS: The fluid extracts were prepared by maceration-percolation with hydroalcoholic solution according to the methodology described in the Brazilian Pharmacopoeia. These extracts were cleaned-up through solid phase extraction (SPE) and chemically characterized by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-ESI-QTOF MS/MS). Gastroprotective and anti-inflammatory activities of the extracts (700 or 1000 mg/kg) were assessed on ethanol-induced gastric lesions and Croton oil-induced ear edema in rats, respectively. The extracts were evaluated for cytotoxicity in vitro. RESULTS: The UPLC-ESI-QTOF-MS/MS analysis evidenced the presence of chalcones, flavonoids and tannins. Gastroprotective and anti-inflammatory activities achieved with fluid extracts from the stems and leaves was similar to inner bark. The fluid extracts were not toxic. CONCLUSION: It is possible to replace the inner bark of the adult tree for the stems and leaves from the shoots as raw material to be used in the preparation of its the phytotherapeutics. Therefore, this finding may help in the implementation of public policies that ensure the conservation of the species along with its sustainable use for pharmaceutical purposes.


Assuntos
Anacardiaceae , Anti-Inflamatórios/uso terapêutico , Antiulcerosos/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Antiulcerosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Etanol , Células HEK293 , Humanos , Camundongos , Casca de Planta , Extratos Vegetais/farmacologia , Folhas de Planta , Caules de Planta , Úlcera Gástrica/tratamento farmacológico
5.
Arq. bras. med. vet. zootec. (Online) ; 70(2): 401-409, mar.-abr. 2018. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-910389

RESUMO

This study was performed to evaluate the effects of autoclaving and storage in 85% glycerol on cortical bone from dogs infected with Leishmania sp. We used 42 cadavers with leishmaniasis. The dogs were evaluated for the presence of Leishmania sp. in culture of bone marrow and by culturing cortical bone. From the infected animals, we harvested 42 diaphysis of the right femur for culture of cortical bone before and after autoclaving or storage in glycerol. There was no significant difference in growth of the parasite in culture of bone marrow or cortical bone. There was no growth of Leishmania sp. in culture of samples after autoclaving or storage in glycerol. Both treatments were effective in preventing the growth of the parasite in vitro, so it was considered viable for grafting.(AU)


Este estudo teve por objetivo avaliar os efeitos da esterilização em autoclave e do armazenamento em glicerol a 85% no osso cortical de cães infectados por Leishmania sp. Foram utilizados 42 cadáveres de cães com leishmaniose. Os cães foram avaliados para a presença de Leishmania sp. em cultura de medula óssea e de osso cortical. Foram coletadas 42 diáfises do fêmur direito para cultura do osso cortical antes e após a esterilização e o armazenamento em glicerol. Não houve diferença significativa no crescimento do parasito em cultura utilizando-se medula óssea ou osso cortical. Não houve crescimento de Leishmania sp. em cultura de amostras de osso cortical após a autoclavagem ou o armazenamento em glicerol. Ambos os tratamentos foram eficazes na prevenção do crescimento do parasita in vitro, de modo que foram considerados viáveis para enxerto.(AU)


Assuntos
Animais , Cães , Leishmania infantum/patogenicidade , Esterilização/estatística & dados numéricos , Transplante Ósseo/veterinária , Glicerol
6.
Arq. bras. med. vet. zootec ; 66(3): 731-736, 06/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-718074

RESUMO

Considering the venereal transmission of visceral leishmaniasis from dogs to bitches, the aim of this study was to verify if the penile surface and smegma from infected dogs can be the source of parasites in bitches. Twelve Leishmania infantum infected dogs had semen and smegma samples collected for submission to PCR identification of the DNA of the parasite. Semen (41.7 percent) and smegma (50.0 percent) have similar positive incidence (P>0.05; Fisher's exact test), with 58.3 percent of the dogs positive for semen and/or smegma samples. The proportion of positivity for both semen and smegma was 33.3 percent, but 8.3 percent was positive only for semen, and 16.7 percent only for smegma, revealing a moderate agreement between tests (K=0.5; Kappa index). It was concluded that Leishmania infantum is present in the smegma of contaminated dogs and it can be a source of parasites for the semen and the bitch...


Tendo em vista a transmissão venérea da leishmaniose visceral do cão para a cadela, o objetivo deste estudo foi verificar se a superfície peniana e o esmegma de cães infectados poderiam ser a fonte de parasitas para a fêmea. Amostras de sêmen e esmegma de 12 cães infectados com Leishmania infantum foram submetidas à identificação do DNA do parasita por PCR. As incidências de positividade no sêmen (41,7 por cento) e no esmegma (50,0 por cento) foram semelhantes (P>0,05; teste exato de Fisher), sendo 58,3 por cento dos cães positivos para sêmen e/ou esmegma. A positividade para sêmen e esmegma juntos ocorreu em 33,3 por cento, mas em 8,3 por cento dos casos apenas no sêmen, e em 16,7 por cento apenas no esmegma, o que revela uma concordância moderada entre os testes (K=0,5; índice Kappa). Conclui-se que a Leishmania infantum está presente no esmegma de cães contaminados, podendo ser a fonte de parasitas para o sêmen e a cadela...


Assuntos
Animais , Masculino , Feminino , Cães , Cães/parasitologia , Esmegma/parasitologia , Leishmaniose Visceral/diagnóstico , Pênis/parasitologia , Prepúcio do Pênis/parasitologia , Sêmen/parasitologia , Doenças Virais Sexualmente Transmissíveis/veterinária , Epididimo , Leishmania/isolamento & purificação
7.
Genet Mol Res ; 12(2): 1603-20, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23765967

RESUMO

Our objective was to establish a minimum number of morphological descriptors for the characterization of banana germplasm and evaluate the efficiency of removal of redundant characters, based on univariate and multivariate statistical analyses. Phenotypic characterization was made of 77 accessions from Bahia, Brazil, using 92 descriptors. The selection of the descriptors was carried out by principal components analysis (quantitative) and by entropy (multi-category). Efficiency of elimination was analyzed by a comparative study between the clusters formed, taking into consideration all 92 descriptors and smaller groups. The selected descriptors were analyzed with the Ward-MLM procedure and a combined matrix formed by the Gower algorithm. We were able to reduce the number of descriptors used for characterizing the banana germplasm (42%). The correlation between the matrices considering the 92 descriptors and the selected ones was 0.82, showing that the reduction in the number of descriptors did not influence estimation of genetic variability between the banana accessions. We conclude that removing these descriptors caused no loss of information, considering the groups formed from pre-established criteria, including subgroup/subspecies.


Assuntos
Ecótipo , Musa/genética , Agricultura , Algoritmos , Entropia , Variação Genética , Análise Multivariada , Musa/anatomia & histologia , Fenótipo , Análise de Componente Principal , Sementes/crescimento & desenvolvimento
8.
Free Radic Biol Med ; 60: 17-28, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23376033

RESUMO

Our group assays natural products that are less toxic and more effective than available nitroheterocycles as promising therapeutic options for patients with Chagas disease. Our previous study reported the trypanocidal activity of eupomatenoid-5, a neolignan isolated from the leaves of Piper regnellii var. pallescens, against the three main parasitic forms of Trypanosoma cruzi. The present study further characterizes the biochemical and morphological alterations induced by this compound to elucidate the mechanisms of action involved in the cell death of T. cruzi. We show that eupomatenoid-5 induced oxidative imbalance in the three parasitic forms, especially trypomastigotes, reflected by a decrease in the activity of trypanothione reductase and increase in the formation of reactive oxygen species (ROS). A reduction of mitochondrial membrane potential was then triggered, further impairing the cell redox system through the production of more ROS and reactive nitrogen species. Altogether, these effects led to oxidative stress, reflected by lipid peroxidation and DNA fragmentation. These alterations are key events in the induction of parasite death through various pathways, including apoptosis, necrosis, and autophagy.


Assuntos
Benzofuranos/farmacologia , Doença de Chagas/tratamento farmacológico , NADH NADPH Oxirredutases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Benzofuranos/química , Morte Celular/efeitos dos fármacos , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Radicais Livres/metabolismo , Radicais Livres/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fenóis/química , Piper/química , Extratos Vegetais/química , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/patogenicidade
9.
Braz. j. microbiol ; 43(3)July-Sept. 2012.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469580

RESUMO

A semi-intensive wildlife boars farm presented a clinical history of high mortality in 70 - 90 days-old pigs (> 50 %). Two 90 days-old animals with weight loss and wasting were necropsied and the samples tested for PCV2 by polymerase chain reaction (PCR). The genetic material of PCV2 was sequenced and classified into the PCV2a genotype together with PCV2 sequences obtained from samples of Poland, Brazil, Slovenia and Greece wild boars.

10.
Braz. j. microbiol ; 43(3): 1022-1025, July-Sept. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-656668

RESUMO

A semi-intensive wildlife boars farm presented a clinical history of high mortality in 70 - 90 days-old pigs (> 50 %). Two 90 days-old animals with weight loss and wasting were necropsied and the samples tested for PCV2 by polymerase chain reaction (PCR). The genetic material of PCV2 was sequenced and classified into the PCV2a genotype together with PCV2 sequences obtained from samples of Poland, Brazil, Slovenia and Greece wild boars.


Assuntos
Animais , Animais Selvagens/genética , Sequência de Bases , Infecções por Circoviridae , Circovirus/genética , Circovirus/isolamento & purificação , Técnicas In Vitro , Reação em Cadeia da Polimerase/métodos , Suínos/genética , Animais , Genótipo , Métodos , Mortalidade
11.
Braz J Microbiol ; 43(3): 1022-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24031922

RESUMO

A semi-intensive wildlife boars farm presented a clinical history of high mortality in 70 - 90 days-old pigs (> 50 %). Two 90 days-old animals with weight loss and wasting were necropsied and the samples tested for PCV2 by polymerase chain reaction (PCR). The genetic material of PCV2 was sequenced and classified into the PCV2a genotype together with PCV2 sequences obtained from samples of Poland, Brazil, Slovenia and Greece wild boars.

12.
Genet Mol Res ; 10(4): 3976-86, 2011 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-22033908

RESUMO

Bananas are among the most important fruit crops worldwide, being cultivated in more than 120 countries, mainly by small-scale producers. However, short-stature high-yielding bananas presenting good agronomic characteristics are hard to find. Consequently, wind continues to damage a great number of plantations each year, leading to lodging of plants and bunch loss. Development of new cultivars through conventional genetic breeding methods is hindered by female sterility and the low number of seeds. Mutation induction seems to have great potential for the development of new cultivars. We evaluated genetic dissimilarity among putative 'Preciosa' banana mutants generated by gamma-ray irradiation, using morphoagronomic characteristics and ISSR markers. The genetic distances between the putative 'Preciosa' mutants varied from 0.21 to 0.66, with a cophenetic correlation coefficient of 0.8064. We found good variability after irradiation of 'Preciosa' bananas; this procedure could be useful for banana breeding programs aimed at developing short-stature varieties with good agronomic characteristics.


Assuntos
Raios gama , Variação Genética , Musa/genética , Mutação , Cruzamento , Repetições de Microssatélites , Análise Multivariada , Musa/classificação , Musa/fisiologia , Sementes/genética
13.
Biosens Bioelectron ; 26(9): 3932-7, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21489775

RESUMO

Cyanobacteria deteriorate the water quality and are responsible for emerging outbreaks and epidemics causing harmful diseases in Humans and animals because of their toxins. Microcystin-LR (MCT) is one of the most relevant cyanotoxin, being the most widely studied hepatotoxin. For safety purposes, the World Health Organization recommends a maximum value of 1 µg L(-1) of MCT in drinking water. Therefore, there is a great demand for remote and real-time sensing techniques to detect and quantify MCT. In this work a Fabry-Pérot sensing probe based on an optical fibre tip coated with a MCT selective thin film is presented. The membranes were developed by imprinting MCT in a sol-gel matrix that was applied over the tip of the fibre by dip coating. The imprinting effect was obtained by curing the sol-gel membrane, prepared with (3-aminopropyl) trimethoxysilane (APTMS), diphenyl-dimethoxysilane (DPDMS), tetraethoxysilane (TEOS), in the presence of MCT. The imprinting effect was tested by preparing a similar membrane without template. In general, the fibre Fabry-Pérot with a Molecular Imprinted Polymer (MIP) sensor showed low thermal effect, thus avoiding the need of temperature control in field applications. It presented a linear response to MCT concentration within 0.3-1.4 µg L(-1) with a sensitivity of -12.4±0.7 nm L µg(-1). The corresponding Non-Imprinted Polymer (NIP) displayed linear behaviour for the same MCT concentration range, but with much less sensitivity, of -5.9±0.2 nm L µg(-1). The method shows excellent selectivity for MCT against other species co-existing with the analyte in environmental waters. It was successfully applied to the determination of MCT in contaminated samples. The main advantages of the proposed optical sensor include high sensitivity and specificity, low-cost, robustness, easy preparation and preservation.


Assuntos
Técnicas Biossensoriais , Interferometria , Microcistinas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Cianobactérias/química , Água Potável/química , Toxinas Marinhas , Membranas/química , Microcistinas/química , Impressão Molecular , Fibras Ópticas , Polimetil Metacrilato
14.
Parasitology ; 137(11): 1661-70, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20546638

RESUMO

SUMMARY: Chagas' disease is a debilitating but comparatively neglected illness that affects about 15 million people. There is an urgent need to develop new, more effective, and less-toxic compounds. In this study, we assessed the in vitro anti-trypanosomal activity of the sesquiterpene elatol from the Brazilian red seaweed Laurencia dendroidea. We used electron microscopy to evaluate the effect of elatol on the morphology and ultrastructure of the parasite. Elatol showed a dose-dependent effect against the epimastigote, trypomastigote, and amastigote forms, with IC50 values of 45.4, 1.38, and 1.01 microm, respectively. Observation of treated intracellular amastigotes by light microscopy demonstrated a total elimination of the infection at a dose of 3.0 microm. In addition, the compound did not affect the red blood cells, and the CC50 value for LLCMK2 cells was 27.0 microm. Transmission and scanning electron micrographs showed aberrant-shaped cells and breaks in the plasma membrane, prominent swollen mitochondria, and extensive formation of cytoplasmic vacuoles in all the forms. This is the first report of the anti-trypanosomal effect of the sesquiterpene elatol.


Assuntos
Laurencia/metabolismo , Compostos de Espiro/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Humanos , Concentração Inibidora 50 , Laurencia/classificação , Microscopia Eletrônica , Testes de Sensibilidade Parasitária , Compostos de Espiro/química , Compostos de Espiro/metabolismo , Tripanossomicidas/química , Tripanossomicidas/metabolismo , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/ultraestrutura
15.
Appl Opt ; 47(27): 4841-8, 2008 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-18806840

RESUMO

A Sagnac interferometer with a section of a polarization maintaining side-hole fiber for multiparameter measurement is proposed. The sensor was experimentally demonstrated to be sensitive to torsion, temperature, and longitudinal strain, simultaneously. The birefringence in the investigated side-hole fiber is induced simultaneously by the elliptical shape of a germanium-doped core and by field overlap with the air holes surrounding the core. The latter effect is purely geometrical and causes high chromatic dispersion of the group birefringence in the long wavelength range, which results in a different period of spectral interference fringes. A different wavelength response is obtained for each interference fringe peak when the fiber is subjected to torsion, temperature, or longitudinal strain. A matrix equation for simultaneous measurement of the three parameters--torsion, temperature, and longitudinal strain--is also proposed.

16.
J Neuroimmunol ; 156(1-2): 146-52, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15465605

RESUMO

A growing body of evidence suggests that the pineal hormone, melatonin, has immunomodulatory properties, although very little is known about its effect on leukocytes. Therefore, we aimed to investigate the effect of melatonin and its oxidation product N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) on cytokine production by neutrophils and peripheral blood mononuclear cells (PBMCs). AFMK (0.001-1 mM) inhibits the lipopolysaccharide (LPS)-mediated production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-8 (IL-8) more efficiently in neutrophils than PBMCs. Moreover, the inhibitory activity of AFMK is stronger than that of melatonin. Interestingly, monocytes efficiently oxidize melatonin to AFMK. We conclude that neutrophils are one of the main targets for melatonin and that at least part of the effects described for melatonin on immune cells may be due to its oxidation product, AFMK. We also consider that the oxidation of melatonin may be an important event in the cross-talking between neutrophils and monocytes.


Assuntos
Citocinas/metabolismo , Cinuramina/análogos & derivados , Cinuramina/farmacologia , Melatonina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Análise de Variância , Células Cultivadas , Humanos , Cinuramina/metabolismo , Melatonina/metabolismo , Oxirredução/efeitos dos fármacos
17.
Biochem Biophys Res Commun ; 279(2): 657-62, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11118341

RESUMO

In the presence of hydrogen peroxide, horseradish peroxidase (HRP) catalyzes the production of N(1)-acetyl-N(2)-formyl-5-methoxykynuramine from melatonin. This reaction consumes oxygen and exhibits chemiluminescence in the 440-540 nm region. The excited cleavage product derived from the thermolysis of an intermediate dioxetane is suggested to be the emitting species. Chemiluminescence and the indole ring cleavage product were also observed when HRP/H(2)O(2) was replaced by phorbol myristate acetate or opsonized zymosan-activated neutrophils. Azide, a myeloperoxidase inhibitor, strongly suppressed melatonin oxidation. Superoxide dismutase has a strong inhibitory effect on light emission but catalase and uric acid are without effect on the emission. The oxidation of melatonin by activated neutrophils may be relevant to the in vivo functions of myeloperoxidase and melatonin. The possible biological implication of melatonin oxidation by neutrophils, especially in inflammatory conditions, is discussed.


Assuntos
Melatonina/sangue , Ativação de Neutrófilo , Neutrófilos/fisiologia , Peroxidase/sangue , Catalase/metabolismo , Sequestradores de Radicais Livres/farmacologia , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Técnicas In Vitro , Cinética , Medições Luminescentes , Oxirredução , Espectrofotometria , Superóxido Dismutase/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
18.
Can J Biochem Cell Biol ; 61(10): 1096-101, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6652560

RESUMO

The site of coupling on the hapten was investigated for melatonin, formaldehyde, and protein conjugates. Model reactions of glycine ethyl ester and piperidine with formaldehyde and melatonin suggested that coupling first occurred through the indole nitrogen and then a stable bond was formed at C-2. Cross-reaction studies of antisera stimulated by melatonin, formaldehyde, and protein conjugates support the hypothesis that C-2 is the site of conjugation of melatonin to protein.


Assuntos
Formaldeído , Indóis/metabolismo , Melatonina/metabolismo , Animais , Sítios de Ligação de Anticorpos , Bovinos , Reações Cruzadas , Indóis/imunologia , Ligação Proteica , Radioimunoensaio/métodos , Soroalbumina Bovina/metabolismo
19.
J Immunoassay ; 2(3-4): 263-76, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7345091

RESUMO

We have developed a specific radioimmunoassay for N-acetylserotonin. Cross-reactivity of 23 related or selected compounds is less than 1 percent; sensitivity is 10 to 25 picograms per tube; within assay coefficient of variation is 7.5 to 8.4%; and between assay coefficient of variation is from 7.1 to 11.1%. Satisfactory parallelism has been demonstrated for rat, hamster and rabbit serum, rat and hamster serum extract and rat brain retina and pineal extract. An extracted sample of rat serum gave one peak on HPLC which corresponded to authentic N-acetylserotonin. Daytime levels of N-acetylserotonin have been established for each of the tissues studied. This radioimmunoassay provides a sensitive and specific method for determination of N-acetylserotonin levels in biological tissues.


Assuntos
Serotonina/análogos & derivados , Animais , Sítios de Ligação de Anticorpos , Química Encefálica , Cromatografia Líquida de Alta Pressão , Cricetinae , Reações Cruzadas , Glândula Pineal/análise , Coelhos , Radioimunoensaio , Ratos , Retina/análise , Serotonina/análise , Serotonina/sangue
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