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1.
Epidemiol Psychiatr Sci ; 28(5): 578-588, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30058510

RESUMO

AIMS: To determine the association between the sleep duration and the risk of all-cause mortality in adults. METHODS: A search strategy was conducted in the MEDLINE, CENTRAL, EMBASE and LILACS databases. Searches were also conducted in other databases and unpublished literature. Cohort studies were included without language, time or setting restrictions. The risk of bias was evaluated with a modified Cochrane Collaboration's tool. An analysis of random effects was conducted. The primary outcome was all-cause mortality. The measure of the effect was the risk difference (RD) with a 95% confidence interval (CI). The planned comparisons were 7-9 h of sleep v. <7 h and the same reference v. >9 h. RESULTS: Thirty-nine studies were included in our qualitative analysis, regarding the quantitative analysis, 19 studies were included in <7 v. 7-9 h analysis, and 18 studies in the >9 v. 7-9 h. A low risk of bias was shown for most of the study items. The overall RD for all-cause mortality was 0.09 (95% CI 0.07-0.11) favouring the >9 h group compared with our reference. In contrast, no differences were found between the <7 h and the reference sleep duration groups (RD 0.00, 95% CI 0.00-0.01). CONCLUSION: We found a probable association of long sleep duration and higher mortality; however, it could reflect an underlying systemic or neurological disease that cause sleep fragmentation, deterioration in quality and micro-awakenings.


Assuntos
Mortalidade , Transtornos do Sono-Vigília/fisiopatologia , Sono/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Sono-Vigília/mortalidade , Fatores de Tempo
3.
Genet Mol Res ; 13(3): 5154-8, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25061740

RESUMO

It has been reported in the literature that the Malpighian tubules of Neuroptera in the third instar undergo drastic histological changes, when they stop functioning in osmoregulation and start to secrete silk fibers for a cocoon. Therefore, to increase our knowledge about these cellular alterations that occur in the larvae of Neuroptera, we analyzed the cells that constitute the Malpighian tubules of each larval instar of the species Myrmeleon uniformis, with emphasis on nucleolar activity. Malpighian tubules, after being removed, were fixed on a slide using liquid nitrogen and stained by silver impregnation. In addition, total protein of the tubules was quantified. By analyzing the cells in the first instar larval stage, we observed only two silver-stained nucleolar regions. In cells of second instar larvae, there was an increase in the number of stained regions, and in the third instar, the number of nucleolar regions was very large. Agarose gel electrophoresis indicated that third instar larvae had high synthetic activity, where the total amount of proteins was larger in third instar stage than in the other larval stages. Furthermore, the most abundant proteins displayed molecular weights of about 32-43 kDa and were probably precursors of silk fibers. Thus, the results obtained showed that nucleolar alterations occur in the cells of the Malpighian tubules of larval instars of M. uniformis and this is directly related to the production of silk fibers used by the pupa to ensure the completion of metamorphosis.


Assuntos
Nucléolo Celular/fisiologia , Células Epiteliais/fisiologia , Insetos/fisiologia , Túbulos de Malpighi/fisiologia , Precursores de Proteínas/biossíntese , Seda/biossíntese , Animais , Nucléolo Celular/ultraestrutura , Eletroforese em Gel de Ágar , Células Epiteliais/ultraestrutura , Histocitoquímica , Larva/fisiologia , Túbulos de Malpighi/ultraestrutura , Metamorfose Biológica , Peso Molecular , Pupa/fisiologia
5.
Br J Pharmacol ; 164(2): 372-81, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21434884

RESUMO

BACKGROUND AND PURPOSE: Mounting evidence implicates matrix metalloproteinase (MMP) in the vascular dysfunction and remodelling associated with hypertension. We tested the hypothesis that treatment with pyrrolidine dithiocarbamate (PDTC), which interferes with NF-κB-induced MMPs gene transcription, could exert antihypertensive effects, prevent MMP-2 and MMP-9 up-regulation, and protect against the functional alterations and vascular remodelling of two-kidney, one clip (2K1C) hypertension. EXPERIMENTAL APPROACH: Sham-operated or hypertensive rats were treated with vehicle or PDTC (100 mg·Kg(-1) ·day(-1)) by gavage for 8 weeks. Systolic blood pressure (SBP) was monitored weekly. Aortic rings were isolated to assess endothelium-dependent relaxations. Quantitative morphometry of structural alterations of the aortic wall was carried out in haematoxylin/eosin sections. Formation of vascular reactive oxygen species (ROS), and inducible (i) NOS and phosphorylated-p65 NF-κB subunit expression were measured in the aortas. MMP-2 and MMP-9 aortic levels and gelatinolytic activity were determined by gelatin and in situ zymography and by immunofluorescence. KEY RESULTS: Treatment with PDTC attenuated the increases in SBP and prevented the endothelial dysfunction associated with 2K1C hypertension. Moreover, PDTC reversed the vascular aortic remodelling, the increases in aortic ROS levels and in iNOS and phosphorylated-p65 NF-κB expression found in 2K1C rats. These effects were associated with attenuation of 2K1C up-regulation of aortic MMP-2 and MMP-9 levels and gelatinolytic activity. CONCLUSION AND IMPLICATIONS: These findings suggest that PDTC down-regulates vascular MMPs and ameliorates vascular dysfunction and remodelling in renovascular hypertension, thus providing evidence supporting the suggestion that PDTC is probably a good candidate to be used to treat hypertension.


Assuntos
Anti-Hipertensivos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Metaloproteases/antagonistas & inibidores , Pirrolidinas/farmacologia , Tiocarbamatos/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Hipertensão Renal/complicações , Hipertrofia/tratamento farmacológico , Masculino , Metaloproteases/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar
6.
Med Vet Entomol ; 24(1): 26-31, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20377728

RESUMO

The aim of the present study was to analyse esterase patterns in three triatomine species of Rhodnius genus. Four loci, Est 1, Est 2, Est 3 and Est 4, were found. The corresponding enzymes were characterized as carboxylesterases (E.C. 3.1.1.1) or cholinesterases (E.C. 3.1.1.8) based on inhibitory experiments, using eserine sulphate, malathion, mercury chloride, p-chloromercuribenzoate (pCMB) and iodoacetamide. Low genetic variability was observed: Est 1, Est 2 and Est 3 were monomorphic in Rhodnius domesticus, Rhodnius robustus and Rhodnius neivai, whereas locus Est 4 was polymorphic in the first two species. The UPGMA analysis based on esterase genotypic frequencies indicated greater similarity between R. domesticus and R. robustus when compared with R. neivai. The present study expands our knowledge about genetic variability among triatomines and accords with the hypothesis that R. domesticus is a species derived from R. robustus.


Assuntos
Esterases/genética , Insetos Vetores/enzimologia , Rhodnius/enzimologia , Alelos , Animais , Esterases/antagonistas & inibidores , Variação Genética , Genótipo , Insetos Vetores/genética , Malation/farmacologia , Cloreto de Mercúrio/farmacologia , Fisostigmina/farmacologia , Polimorfismo Genético , Rhodnius/genética , Ácido p-Cloromercurobenzoico/farmacologia
7.
Br J Pharmacol ; 160(1): 77-87, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20331602

RESUMO

BACKGROUND AND PURPOSE: Increased oxidative stress and up-regulation of matrix metalloproteinases (MMPs) may cause structural and functional vascular changes in renovascular hypertension. We examined whether treatment with spironolactone (SPRL), hydrochlorothiazide (HCTZ) or both drugs together modified hypertension-induced changes in arterial blood pressure, aortic remodelling, vascular reactivity, oxidative stress and MMP levels and activity, in a model of renovascular hypertension. EXPERIMENTAL APPROACH: We used the two-kidney,one-clip (2K1C) model of hypertension in Wistar rats. Sham-operated or hypertensive rats were treated with vehicle, SPRL (25 mg.kg(-1).day(-1)), HCTZ (20 mg.kg(-1).day(-1)) or a combination for 8 weeks. Systolic blood pressure was monitored weekly. Aortic rings were isolated to assess endothelium-dependent and -independent relaxations. Morphometry of the vascular wall was carried out in sections of aorta. Aortic NADPH oxidase activity and superoxide production were evaluated. Formation of reactive oxygen species was measured in plasma as thiobarbituric acid-reactive substances. Aortic MMP-2 levels and activity were determined by gelatin and in situ zymography, fluorimetry and immunohistochemistry. KEY RESULTS: Treatment with SPRL, HCTZ or the combination attenuated 2K1C-induced hypertension, and reversed the endothelial dysfunction in 2K1C rats. Both drugs or the combination reversed vascular aortic remodelling induced by hypertension, attenuated hypertension-induced increases in oxidative stress and reduced MMP-2 levels and activity. CONCLUSIONS AND IMPLICATIONS: SPRL or HCTZ, alone or combined, exerted antioxidant effects, and decreased renovascular hypertension-induced MMP-2 up-regulation, thus improving the vascular dysfunction and remodelling found in this model of hypertension.


Assuntos
Antioxidantes/farmacologia , Hidroclorotiazida/farmacologia , Hipertensão Renovascular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Espironolactona/farmacologia , Animais , Antioxidantes/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/enzimologia , Aorta/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Hidroclorotiazida/uso terapêutico , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/fisiopatologia , Técnicas In Vitro , Peróxidos Lipídicos/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Espironolactona/uso terapêutico , Vasodilatação/efeitos dos fármacos
9.
Braz J Biol ; 66(2B): 703-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16906302

RESUMO

Triatomines are insects belonging to the Hemiptera order, Heteroptera suborder, Reduviidae family and Triatominae subfamily. All members of this subfamily are hematophagous. Triatomines evolved from Reduviidae predators and they are probably polyphyletic in origin. The combination of anatomical, physiological and ethological factors observed in this group, as well as the plesiomorphic and apomorphic characters that differentiate the five tribes and fourteen triatomine genera reinforce the polyphiletic hypotesis. However if we consider the five groups of triatomines, the Rhodniini, Cavernicolini, Bolboderini, Linshcosteini and Alberproseniini tribes constitute monophyletic groups, while the Triatomini tribe is considered polyphyletic. The New World is the center of triatomine diversity and seems to be the point of group origin. Of approximately 137 triatomine species, 105 are only found in the Americas. It is now considered that triatomines represent a polyphyletic group defined according to their convergent apomorphic hematophagous characters, which have appeared several times in Reduviidae. This study revises the phylogeny of these vectors of Chagas' disease, covering such topics as the origin of hematophagy in triatomines and ancestral proposal for the group.


Assuntos
Insetos Vetores/classificação , Filogenia , Triatominae/classificação , Animais , Doença de Chagas/transmissão , Insetos Vetores/genética , Triatominae/genética
10.
Braz. j. biol ; Braz. j. biol;66(2b): 703-708, May 2006.
Artigo em Inglês | LILACS | ID: lil-433155

RESUMO

Os triatomíneos são insetos pertencentes à ordem Hemiptera, subordem Heteroptera, família Reduviidae e subfamília Triatominae. Todos os membros desta subfamília são hematófagos. Os triatomíneos surgiram a partir de reduvídeos predadores e provavelmente têm origem polifilética. A combinação dos fatores anatômicos, fisiológicos e etológicos presentes no grupo, bem como os caracteres plésio e apomórficos que diferenciam as cinco tribos e os quatorze gêneros de triatomíneos reforçam a hipótese polifilética. As tribos Rhodniini, Cavernicolini, Bolboderini, Linshcosteini e Alberproseniini constituem grupos monofiléticos, per si, enquanto a tribo Triatomini é considerada polifilética. O Novo Mundo é claramente o centro de diversidade dos triatomíneos e possivelmente é a região de sua origem. Entre as aproximadamente 129 espécies desses insetos, 105 ocorrem somente nas Américas. Atualmente, os triatomíneos são considerados um grupo polifilético, definido com base em seus caracteres apomórficos convergentes relacionados à hematofagia. Acredita-se que este hábito alimentar tenha surgido várias vezes nos Reduviidae durante sua evolução. O presente trabalho faz uma revisão sobre a filogenia destes vetores da Doença de Chagas, aborda tópicos como a origem da hematofagia nos triatomíneos e ancestralidade proposta para o grupo.


Assuntos
Animais , Insetos Vetores/classificação , Filogenia , Triatominae/classificação , Doença de Chagas/transmissão , Insetos Vetores/genética , Triatominae/genética
11.
Genetica ; 126(1-2): 89-99, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16502087

RESUMO

The aim of this study was to characterize esterases in Zaprionus indianus, a drosophilid recently introduced into Brazil. A further aim was study the variation of activity of esterases in the presence of inhibitors and their expression according to sex, sexual activity and age of individual flies. Polymorphisms were detected in two esterase loci (Est-2 and Est-3) and monomorphisms in four others (Est-1, Est-4, Est-5 and Est-6). Biochemical tests using alpha- and beta-naphthyl acetate and the inhibitors malathion, eserine sulphate and PMSF allowed us to classify EST-2 and EST-5 as beta-esterases, both carboxyl-esterases, and EST-1, EST-3, EST-4 and EST-6 as alpha-esterases. EST-1 and EST-3 were classified as carboxyl-esterases and EST-4 and EST-6 as cholinesterases. EST-5 activity was more pronounced in males and EST-2 was restricted to them or to recently copulated females. EST-4, rarely detected, was not characterized. Based on their biochemical characteristics possible roles for these enzymes are suggested.


Assuntos
Drosophilidae/enzimologia , Esterases/química , Fatores Etários , Animais , Brasil , Drosophilidae/genética , Eletroforese em Gel de Poliacrilamida , Esterases/antagonistas & inibidores , Esterases/biossíntese , Esterases/genética , Feminino , Regulação Enzimológica da Expressão Gênica , Larva/enzimologia , Larva/genética , Masculino , Pupa/enzimologia , Pupa/genética , Fatores Sexuais
12.
Braz. J. Biol. ; 66(2)2006.
Artigo em Inglês | VETINDEX | ID: vti-446145

RESUMO

Triatomines are insects belonging to the Hemiptera order, Heteroptera suborder, Reduviidae family and Triatominae subfamily. All members of this subfamily are hematophagous. Triatomines evolved from Reduviidae predators and they are probably polyphyletic in origin. The combination of anatomical, physiological and ethological factors observed in this group, as well as the plesiomorphic and apomorphic characters that differentiate the five tribes and fourteen triatomine genera reinforce the polyphiletic hypotesis. However if we consider the five groups of triatomines, the Rhodniini, Cavernicolini, Bolboderini, Linshcosteini and Alberproseniini tribes constitute monophyletic groups, while the Triatomini tribe is considered polyphyletic. The New World is the center of triatomine diversity and seems to be the point of group origin. Of approximately 137 triatomine species, 105 are only found in the Americas. It is now considered that triatomines represent a polyphyletic group defined according to their convergent apomorphic hematophagous characters, which have appeared several times in Reduviidae. This study revises the phylogeny of these vectors of Chagas' disease, covering such topics as the origin of hematophagy in triatomines and ancestral proposal for the group.


Os triatomíneos são insetos pertencentes à ordem Hemiptera, subordem Heteroptera, família Reduviidae e subfamília Triatominae. Todos os membros desta subfamília são hematófagos. Os triatomíneos surgiram a partir de reduvídeos predadores e provavelmente têm origem polifilética. A combinação dos fatores anatômicos, fisiológicos e etológicos presentes no grupo, bem como os caracteres plésio e apomórficos que diferenciam as cinco tribos e os quatorze gêneros de triatomíneos reforçam a hipótese polifilética. As tribos Rhodniini, Cavernicolini, Bolboderini, Linshcosteini e Alberproseniini constituem grupos monofiléticos, per si, enquanto a tribo Triatomini é considerada polifilética. O Novo Mundo é claramente o centro de diversidade dos triatomíneos e possivelmente é a região de sua origem. Entre as aproximadamente 129 espécies desses insetos, 105 ocorrem somente nas Américas. Atualmente, os triatomíneos são considerados um grupo polifilético, definido com base em seus caracteres apomórficos convergentes relacionados à hematofagia. Acredita-se que este hábito alimentar tenha surgido várias vezes nos Reduviidae durante sua evolução. O presente trabalho faz uma revisão sobre a filogenia destes vetores da Doença de Chagas, aborda tópicos como a origem da hematofagia nos triatomíneos e ancestralidade proposta para o grupo.

13.
Braz. j. biol ; Braz. j. biol;66(2)2006.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467853

RESUMO

Triatomines are insects belonging to the Hemiptera order, Heteroptera suborder, Reduviidae family and Triatominae subfamily. All members of this subfamily are hematophagous. Triatomines evolved from Reduviidae predators and they are probably polyphyletic in origin. The combination of anatomical, physiological and ethological factors observed in this group, as well as the plesiomorphic and apomorphic characters that differentiate the five tribes and fourteen triatomine genera reinforce the polyphiletic hypotesis. However if we consider the five groups of triatomines, the Rhodniini, Cavernicolini, Bolboderini, Linshcosteini and Alberproseniini tribes constitute monophyletic groups, while the Triatomini tribe is considered polyphyletic. The New World is the center of triatomine diversity and seems to be the point of group origin. Of approximately 137 triatomine species, 105 are only found in the Americas. It is now considered that triatomines represent a polyphyletic group defined according to their convergent apomorphic hematophagous characters, which have appeared several times in Reduviidae. This study revises the phylogeny of these vectors of Chagas' disease, covering such topics as the origin of hematophagy in triatomines and ancestral proposal for the group.


Os triatomíneos são insetos pertencentes à ordem Hemiptera, subordem Heteroptera, família Reduviidae e subfamília Triatominae. Todos os membros desta subfamília são hematófagos. Os triatomíneos surgiram a partir de reduvídeos predadores e provavelmente têm origem polifilética. A combinação dos fatores anatômicos, fisiológicos e etológicos presentes no grupo, bem como os caracteres plésio e apomórficos que diferenciam as cinco tribos e os quatorze gêneros de triatomíneos reforçam a hipótese polifilética. As tribos Rhodniini, Cavernicolini, Bolboderini, Linshcosteini e Alberproseniini constituem grupos monofiléticos, per si, enquanto a tribo Triatomini é considerada polifilética. O Novo Mundo é claramente o centro de diversidade dos triatomíneos e possivelmente é a região de sua origem. Entre as aproximadamente 129 espécies desses insetos, 105 ocorrem somente nas Américas. Atualmente, os triatomíneos são considerados um grupo polifilético, definido com base em seus caracteres apomórficos convergentes relacionados à hematofagia. Acredita-se que este hábito alimentar tenha surgido várias vezes nos Reduviidae durante sua evolução. O presente trabalho faz uma revisão sobre a filogenia destes vetores da Doença de Chagas, aborda tópicos como a origem da hematofagia nos triatomíneos e ancestralidade proposta para o grupo.

14.
Cytobios ; 106(412): 125-38, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11503973

RESUMO

Several fitness components in strains of Drosophila mulleri carrying the slow or the fast alleles for the major beta esterase (esterase-4) found in this species, as well as in heterozygous flies in which the slow or fast alleles came from one of the parents, were evaluated. Twelve components were analysed including longevity of both virgins and mated males and females, productivity, viability, including the egg-larva, egg-pupa, egg-imago and pupa-imago periods. These parameters were used to estimate the total fitness for each genotype. The best score was reached by individuals having the Est-4S/Est-4S genotype (scored at 1.000), followed by a fitness value of 0.892 presented by the Est-4F/Est-4S genotype (with the fast allele from maternal origin), 0.863 for the Est-4F/Est-4F and 0.842 for the Est-4S/Est-4Fgenotypes (with Est-4F of maternal origin). These results suggested a higher relative adaptability of the Est-4S/Est-4S genotype followed by the Est-4F/Est-4S hybrid that possessed the allele Est-4S of maternal origin, which was incompatible with predictions of neutral polymorphism.


Assuntos
Adaptação Biológica/genética , Drosophila/crescimento & desenvolvimento , Esterases/genética , Longevidade/genética , Animais , Drosophila/genética , Feminino , Genótipo , Masculino , Comportamento Sexual Animal
15.
Arch Inst Cardiol Mex ; 70(5): 481-5, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-11534099

RESUMO

A case of acute myocardial infarction in a 36 years old patient is presented. Maleness was male, as the only mayor coronary risk factor. He had myocardial infarction associated with ingestion of cold beverage after strenuous physical exercise. A coronariographic study was done postmyocardial infarction, which showed a mild obstruction of the LAD. The most likely cause of the coronary event in this case is coronary spasm and atherosclerosis. A review of the literature on this subject is made.


Assuntos
Bebidas , Temperatura Baixa/efeitos adversos , Exercício Físico , Infarto do Miocárdio/etiologia , Adulto , Humanos , Masculino
16.
Cytobios ; 96(382): 95-107, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10384711

RESUMO

Ten strains of two species in the Drosophila buzzatii cluster (D. serido and D. seriema) were examined as to esterase patterns using polyacrylamide gel electrophoresis. The migration rate of esterases, and their substrate specificity to alpha and beta naphthyl acetates, were analysed. Other esterase features such as inhibition behaviour, presence in males and females and location in the head, thorax or abdomen of flies, were also examined. The present data, together with results obtained by others for eight strains of D. koepferae, D. serido, D. seriema and D. buzzatii, show that 69 bands have been detected in the eighteen strains studied. This total number of bands was used for comparison of strains and species by similarity index, analysis of dependence and cluster analysis. The comparisons confirmed the existence of a high degree of similarity among D. seriema strains and among D. koepferae strains, but indicated differentiation among the D. serido strains. Two strains (D69R2 and D69R5) which differed from the others of the latter species, showed closer affinities with D. buzzatii, which indicates the need for further work on those strains classified as D. serido.


Assuntos
Drosophila/classificação , Esterases/metabolismo , Filogenia , Animais , Drosophila/enzimologia , Evolução Molecular , Feminino , Proteínas de Insetos/metabolismo , Masculino , Especificidade da Espécie , Especificidade por Substrato
17.
Cytobios ; 90(361): 81-94, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9474771

RESUMO

Four population samples of Haematobia irritans (horn flies), collected from farms and subjected, or not, to insecticide control, were analysed as to esterase bands by polyacrylamide gel electrophoresis. Eight esterase bands were detected in this species, a low number when compared with flies of other genera. The reduced number of esterase variants of H. irritans is attributed to their parasitic behaviour and blood-dependence for food. Unlike other fly species whose esterase bands exhibit affinity to both alpha- and beta-naphthyl acetates, the esterases in H. irritans seem to be of a single kind, all preferentially hydrolysing alpha-naphthyl. The four populations were very similar as to esterase bands. In relation to the frequencies of patterns resulting from combining bands, Nova Aliança and Birigui were more alike than the other two populations. Inhibitors were used in an attempt to classify five of the esterase bands. The results indicate one acetylcholinesterase, two acetylesterases and two carboxylesterases.


Assuntos
Esterases/análise , Isoenzimas/análise , Muscidae/enzimologia , Animais , Brasil , Eletroforese em Gel de Poliacrilamida/métodos , Inibidores Enzimáticos/farmacologia , Esterases/antagonistas & inibidores , Feminino , Inseticidas , Masculino
18.
Antimicrob Agents Chemother ; 40(7): 1699-702, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8807065

RESUMO

We assessed the colonization patterns, over time, of three sentinel drug-resistant enteric bacterial genera in samples from a cohort of 20 healthy small children in a periurban community in Mexico. The children were monitored during a 13-week period by means of weekly home visits and examinations of stool collections. These specimens were tested for the presence of Escherichia coli, Klebsiella species, and Shigella species resistant to one or more of seven antimicrobial agents. Ninety, 77, and 62% of the stool specimens had E. coli isolates resistant to ampicillin, trimethoprim, and tetracycline, respectively. Simultaneous resistance to more than one antibiotic by an E. coli isolate was observed in 88.5% of stool samples. Persistent fecal shedding of ampicillin-, trimethoprim-, and tetracycline-resistant E. coli occurred during the study period in the majority of children. We detected colonization by E. coli resistant to chloramphenicol, gentamicin, nitrofurantoin, or norfloxacin, as well as by Klebsiella species and Shigella species resistant to one of these antibiotics, in fewer children and for shorter periods. These data suggest the common and persistent intestinal shedding of multidrug-resistant E. coli strains by small healthy children.


Assuntos
Resistência a Ampicilina , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Klebsiella/efeitos dos fármacos , Shigella/efeitos dos fármacos , Resistência a Tetraciclina , Resistência a Trimetoprima , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , México
19.
Cytobios ; 84(336): 13-29, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8681607

RESUMO

A comparative analysis was made of the esterase isoenzyme patterns of eight iso-female lines, four of Drosophila serido (B31 D1, A55, B59, Q1, B50Q3), two of D. koepferae (B20D2 and B25D7), one of D. seriema (A95) and one of D. buzzatii (Buz). In all, 43 bands in the spectrum of esterase isoenzymes were detected by electrophoresis in polyacrylamide gels. They showed variations in specific reactions with alpha and beta-naphthyl acetate, number of patterns yielded in their intra-isofemale line combinations, frequencies of such combinations and the thickness and staining degree of some bands, in different individuals, lines and species. Among bands detected exclusively in males, seven may be considered sex-specific (5 alpha-esterases and 2 beta-esterases). These male-specific alpha-esterases have in common the inability to cleave beta-naphthyl acetate in the absence of alpha-naphthyl, denoting a possible common function. The similarity index (SI) and analysis of dependence were calculated in an attempt to quantify the differentiation of the iso-female lines studied, on the basis of esterase bands. SI mean value allowed the separation of the isofemale lines into five classes. Each species had its own pattern of esterase bands, but some bands were shared. A divergence hypothesis for the isofemale lines and the species is discussed.


Assuntos
Drosophila/enzimologia , Esterases/análise , Animais , Evolução Biológica , Drosophila/química , Eletroforese em Gel de Poliacrilamida , Feminino , Masculino , Fatores Sexuais
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