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1.
mBio ; 10(3)2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138741

RESUMO

Prokaryotes represent an ancestral lineage in the tree of life and constitute optimal resources for investigating the evolution of genomes in unicellular organisms. Many bacterial species possess multipartite genomes offering opportunities to study functional variations among replicons, how and where new genes integrate into a genome, and how genetic information within a lineage becomes encoded and evolves. To analyze these issues, we focused on the model soil bacterium Sinorhizobium meliloti, which harbors a chromosome, a chromid (pSymB), a megaplasmid (pSymA), and, in many strains, one or more accessory plasmids. The analysis of several genomes, together with 1.4 Mb of accessory plasmid DNA that we purified and sequenced, revealed clearly different functional profiles associated with each genomic entity. pSymA, in particular, exhibited remarkable interstrain variation and a high density of singletons (unique, exclusive genes) featuring functionalities and modal codon usages that were very similar to those of the plasmidome. All this evidence reinforces the idea of a close relationship between pSymA and the plasmidome. Correspondence analyses revealed that adaptation of codon usages to the translational machinery increased from plasmidome to pSymA to pSymB to chromosome, corresponding as such to the ancestry of each replicon in the lineage. We demonstrated that chromosomal core genes gradually adapted to the translational machinery, reminiscent of observations in several bacterial taxa for genes with high expression levels. Such findings indicate a previously undiscovered codon usage adaptation associated with the chromosomal core information that likely operates to improve bacterial fitness. We present a comprehensive model illustrating the central findings described here, discussed in the context of the changes occurring during the evolution of a multipartite prokaryote genome.IMPORTANCE Bacterial genomes usually include many thousands of genes which are expressed with diverse spatial-temporal patterns and intensities. A well-known evidence is that highly expressed genes, such as the ribosomal and other translation-related proteins (RTRPs), have accommodated their codon usage to optimize translation efficiency and accuracy. Using a bioinformatic approach, we identify core-genes sets with different ancestries, and demonstrate that selection processes that optimize codon usage are not restricted to RTRPs but extended at a genome-wide scale. Such findings highlight, for the first time, a previously undiscovered adaptation strategy associated with the chromosomal-core information. Contrasted with the translationally more adapted genes, singletons (i.e., exclusive genes, including those of the plasmidome) appear as the gene pool with the less-ameliorated codon usage in the lineage. A comprehensive summary describing the inter- and intra-replicon heterogeneity of codon usages in a complex prokaryote genome is presented.


Assuntos
Cromossomos Bacterianos , Uso do Códon , Evolução Molecular , Genoma Bacteriano , Sinorhizobium meliloti/genética , Biologia Computacional , DNA Ribossômico/genética , Genes Bacterianos , Plasmídeos/genética , Replicon
2.
Braz. j. biol ; 77(4): 696-702, Nov. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888807

RESUMO

Abstract The transport of live fish is a routine practice in aquaculture and constitutes a considerable source of stress to the animals. The addition of anesthetic to the water used for fish transport can prevent or mitigate the deleterious effects of transport stress. This study investigated the effects of the addition of eugenol (EUG) (1.5 or 3.0 µL L-1) and essential oil of Lippia alba (EOL) (10 or 20 µL L-1) on metabolic parameters (glycogen, lactate and total protein levels) in liver and muscle, acetylcholinesterase activity (AChE) in muscle and brain, and the levels of protein carbonyl (PC), thiobarbituric acid reactive substances (TBARS) and nonprotein thiol groups (NPSH) and activity of glutathione-S-transferase in the liver of silver catfish (Rhamdia quelen; Quoy and Gaimard, 1824) transported for four hours in plastic bags (loading density of 169.2 g L-1). The addition of various concentrations of EUG (1.5 or 3.0 µL L-1) and EOL (10 or 20 µL L-1) to the transport water is advisable for the transportation of silver catfish, since both concentrations of these substances increased the levels of NPSH antioxidant and decreased the TBARS levels in the liver. In addition, the lower liver levels of glycogen and lactate in these groups and lower AChE activity in the brain (EOL 10 or 20 µL L-1) compared to the control group indicate that the energetic metabolism and neurotransmission were lower after administration of anesthetics, contributing to the maintenance of homeostasis and sedation status.


Resumo O transporte de peixes vivos é uma prática rotineira na aquicultura e constitui uma fonte considerável de estresse para os animais. A adição de anestésicos na água utilizada para o transporte de peixes pode prevenir ou mitigar os efeitos nocivos do estresse de transporte. Este estudo investigou os efeitos da adição de eugenol (EUG) (1,5 ou 3,0 mL L-1) e óleo essencial de Lippia alba (OEL) (10 ou 20 mL L-1) em parâmetros metabólicos (níveis de glicogênio, lactato e proteína total) no fígado e músculos, a atividade da acetilcolinesterase (AChE) no músculo e no cérebro, e os níveis de proteína carbonil (PC), ácido tiobarbitúrico (TBARS) e grupos tióis não proteicos (NPSH) e atividade da glutationa-S-transferase no fígado de jundiás (Rhamdia quelen; Quoy e Gaimard, 1824) transportados por quatro horas em sacos plásticos (densidade de carga de 169,2 g L-1). A adição de várias concentrações de EUG (1,5 ou 3,0 mL L-1) e OEL (10 ou 20 mL L-1) na água de transporte é aconselhável para o transporte do jundiá, uma vez que ambas concentrações destas substâncias aumentaram os níveis do antioxidante NPSH e diminuíram os níveis de TBARS no fígado. Além disso, os níveis mais baixos de glicogénio e lactato no fígado destes grupos e menor atividade de AChE no cérebro (EOL 10 ou 20 mL L-1) em comparação com o grupo controle indicam que o metabolismo energético e neurotransmissão foram menores após a administração dos anestésicos, contribuindo para a manutenção do estado de homeostase e sedação.


Assuntos
Animais , Peixes-Gato/fisiologia , Eugenol/farmacologia , Óleos Voláteis/farmacologia , Aquicultura , Lippia/química , Anestésicos/farmacologia , Meios de Transporte
3.
Braz. J. Biol. ; 77(4): 696-702, Nov. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-20370

RESUMO

The transport of live fish is a routine practice in aquaculture and constitutes a considerable source of stress to the animals. The addition of anesthetic to the water used for fish transport can prevent or mitigate the deleterious effects of transport stress. This study investigated the effects of the addition of eugenol (EUG) (1.5 or 3.0 µL L1) and essential oil of Lippia alba (EOL) (10 or 20 µL L1) on metabolic parameters (glycogen, lactate and total protein levels) in liver and muscle, acetylcholinesterase activity (AChE) in muscle and brain, and the levels of protein carbonyl (PC), thiobarbituric acid reactive substances (TBARS) and nonprotein thiol groups (NPSH) and activity of glutathione-S-transferase in the liver of silver catfish (Rhamdia quelen; Quoy and Gaimard, 1824) transported for four hours in plastic bags (loading density of 169.2 g L1). The addition of various concentrations of EUG (1.5 or 3.0 µL L1) and EOL (10 or 20 µL L1) to the transport water is advisable for the transportation of silver catfish, since both concentrations of these substances increased the levels of NPSH antioxidant and decreased the TBARS levels in the liver. In addition, the lower liver levels of glycogen and lactate in these groups and lower AChE activity in the brain (EOL 10 or 20 µL L1) compared to the control group indicate that the energetic metabolism and neurotransmission were lower after administration of anesthetics, contributing to the maintenance of homeostasis and sedation status.(AU)


O transporte de peixes vivos é uma prática rotineira na aquicultura e constitui uma fonte considerável de estresse para os animais. A adição de anestésicos na água utilizada para o transporte de peixes pode prevenir ou mitigar os efeitos nocivos do estresse de transporte. Este estudo investigou os efeitos da adição de eugenol (EUG) (1,5 ou 3,0 mL L1) e óleo essencial de Lippia alba (OEL) (10 ou 20 mL L1) em parâmetros metabólicos (níveis de glicogênio, lactato e proteína total) no fígado e músculos, a atividade da acetilcolinesterase (AChE) no músculo e no cérebro, e os níveis de proteína carbonil (PC), ácido tiobarbitúrico (TBARS) e grupos tióis não proteicos (NPSH) e atividade da glutationa-S-transferase no fígado de jundiás (Rhamdia quelen; Quoy e Gaimard, 1824) transportados por quatro horas em sacos plásticos (densidade de carga de 169,2 g L1). A adição de várias concentrações de EUG (1,5 ou 3,0 mL L1) e OEL (10 ou 20 mL L1) na água de transporte é aconselhável para o transporte do jundiá, uma vez que ambas concentrações destas substâncias aumentaram os níveis do antioxidante NPSH e diminuíram os níveis de TBARS no fígado. Além disso, os níveis mais baixos de glicogénio e lactato no fígado destes grupos e menor atividade de AChE no cérebro (EOL 10 ou 20 mL L1) em comparação com o grupo controle indicam que o metabolismo energético e neurotransmissão foram menores após a administração dos anestésicos, contribuindo para a manutenção do estado de homeostase e sedação.(AU)


Assuntos
Animais , Peixes-Gato/metabolismo , Estresse Fisiológico , Eugenol/farmacologia , Óleos Voláteis/farmacologia , Lippia , Biomarcadores/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-28596905

RESUMO

BACKGROUND: Engagement and training of educators in student mental health holds promise for promoting access to care as a task sharing strategy but has not been well-studied in low-income regions. METHODS: We used a prospective and convergent mixed methods design to evaluate a customized school mental health 2½ day training for teachers in rural Haiti (n = 22) as the initial component of formative research developing a school-based intervention to promote student mental health. Training prepared teachers to respond to student mental health needs by providing psychoeducational and practical support to facilitate access to care. We examined level of participation and evaluated feasibility, acceptability, and perceived effectiveness by calculating mean scores on self-report Likert-style items eliciting participant experience. We examined effectiveness of the training on improving mental health knowledge and attitudes by comparing mean scores on an assessment administered pre- and post-training. Finally, we examined self-report written open-ended responses and focus group discussion (FGD) interview data bearing on perceived feasibility, acceptability, and effectiveness to contextualize participant ratings of training and to identify recommendations for enhancing the utility of mental health training locally for educators. RESULTS: Mean scores of knowledge and attitudes significantly improved between the pre-test and post-tests; e.g., knowledge improved from 58% correct at baseline to 68% correct on the second post-test (p = 0.039). Mean ratings of the training were favorable across all categories and FGD data demonstrated widespread participant endorsement of training acceptability and effectiveness; participants recommended extending the duration and number of training sessions. CONCLUSIONS: Findings support feasibility, acceptability, and a limited scope of effectiveness of brief mental health training for secondary school teachers in Haiti. Further development of approaches to engage teachers in promoting school mental health through training is warranted.

5.
Braz J Biol ; 77(4): 696-702, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28492807

RESUMO

The transport of live fish is a routine practice in aquaculture and constitutes a considerable source of stress to the animals. The addition of anesthetic to the water used for fish transport can prevent or mitigate the deleterious effects of transport stress. This study investigated the effects of the addition of eugenol (EUG) (1.5 or 3.0 µL L-1) and essential oil of Lippia alba (EOL) (10 or 20 µL L-1) on metabolic parameters (glycogen, lactate and total protein levels) in liver and muscle, acetylcholinesterase activity (AChE) in muscle and brain, and the levels of protein carbonyl (PC), thiobarbituric acid reactive substances (TBARS) and nonprotein thiol groups (NPSH) and activity of glutathione-S-transferase in the liver of silver catfish (Rhamdia quelen; Quoy and Gaimard, 1824) transported for four hours in plastic bags (loading density of 169.2 g L-1). The addition of various concentrations of EUG (1.5 or 3.0 µL L-1) and EOL (10 or 20 µL L-1) to the transport water is advisable for the transportation of silver catfish, since both concentrations of these substances increased the levels of NPSH antioxidant and decreased the TBARS levels in the liver. In addition, the lower liver levels of glycogen and lactate in these groups and lower AChE activity in the brain (EOL 10 or 20 µL L-1) compared to the control group indicate that the energetic metabolism and neurotransmission were lower after administration of anesthetics, contributing to the maintenance of homeostasis and sedation status.


Assuntos
Anestésicos/farmacologia , Aquicultura , Peixes-Gato/fisiologia , Eugenol/farmacologia , Lippia/química , Óleos Voláteis/farmacologia , Animais , Meios de Transporte
6.
J Am Soc Hypertens ; 7(6): 477-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23969287

RESUMO

We assessed the association between adherence to antihypertensive drug treatment and patient's perception of uncontrolled blood pressure (BP) in diabetic hypertensive subjects. This was a cross-sectional study that evaluated adherence to antihypertensives (Morisky questionnaire), patients' perception of abnormal BP, office BP, and ambulatory BP monitoring in diabetic hypertensive subjects. We evaluated 323 patients, 65.2% women, aged 56.5 ± 7 years, glycosylated hemoglobin (HbA1c) 8.0% (range, 6.9%-9.6%), diabetes duration of 10 years (range, 5-17 years). Adherence to drug treatment was 51.4%. Patients who reported hypertension-related symptoms (60.4%) had a lower level of adherence (P < .001). Non-adherence occurred four times more frequently in patients who reported hypertension-related symptoms (P < .001, adjusted for use of three or more anti-hypertensives, age, and duration of diabetes). Non-adherents had higher office diastolic BP (83.6 ± 11.9 vs. 79.8 ± 9.9; P = .003), but no difference between groups was observed considering systolic, diastolic, and mean BP evaluated by ambulatory BP monitoring. Low rates of adherence to antihypertensive drug treatment were observed in outpatient hypertensive diabetic subjects. Perception of uncontrolled BP levels was strongly and independently associated with non-adherence. Non-adherence determined repercussion on office BP that may have clinical implications in cardiovascular risk.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus/psicologia , Hipertensão/tratamento farmacológico , Hipertensão/psicologia , Adesão à Medicação/psicologia , Monitorização Ambulatorial da Pressão Arterial , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Percepção , Fatores de Risco , Inquéritos e Questionários
7.
Epidemiol Infect ; 140(8): 1372-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22008212

RESUMO

SUMMARY Methicillin-resistant Staphylococcus aureus (MRSA) commonly causes infection in hospitalized patients. Resistance is due to the acquisition of mecA gene located on the chromosomal element SCCmec and to date 12 types have been identified. Specific epidemic clones of MRSA have emerged with enhanced ability to spread within and among hospitals and to cross national boundaries. We studied 30 isolates from patients with MRSA infections at two hospitals in Porto Alegre city from April to December, 2008 and determined their SCCmec type by PCR. Representative strains were typed by PFGE. Eighteen (60%) isolates carried SCCmec type III and had PFGE profiles clonally related to the previously characterized Brazilian epidemic clone, and 11 (36·7%) isolates with pulsotypes closely related to the Cordobes/Chilean clone harboured SCCmec type I. To the best of our knowledge, this is the first report of the appearance of Cordobes/Chilean clone involved in nosocomial infection in Brazil.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Brasil/epidemiologia , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica/fisiologia , Humanos , Meticilina/farmacologia , Proteínas de Ligação às Penicilinas
8.
Vet Parasitol ; 178(1-2): 15-21, 2011 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-21255934

RESUMO

The aim of this study was to determine oxidative stress parameters in the liver, gill and muscle of silver catfish juveniles infected with Ichthyophthirius multifiliis and maintained at pH 5.0 or 7.0 for three days. Juveniles were infected by adding one I. multifiliis-infected juvenile and water containing theronts to tanks. After the appearance of white spots on the skin, infected juveniles exposed to pH 5.0 and 7.0 showed significantly higher thiobarbituric acid reactive substances (TBARS) levels in the liver and gills compared to uninfected juveniles. Liver of infected juveniles exposed to pH 7.0 showed higher catalase (CAT) and lower glutathione-S-transferase (GST) activities, but those maintained at pH 5.0 showed significantly higher GST activity than uninfected juveniles. The gills of infected juveniles showed significantly higher CAT (day two) and GST activity at both pH 5.0 and 7.0 compared to uninfected juveniles. Muscle of infected juveniles showed significantly lower CAT and GST activity and TBARS levels (at day three) when maintained at both pH 5.0 and 7.0 compared to uninfected juveniles. In conclusion, I. multifiliis infection induces liver and gill damage via lipid peroxidation products in silver catfish, but higher antioxidant enzyme activity could indicate a greater degree of protection against this parasite.


Assuntos
Peixes-Gato , Infecções por Cilióforos/veterinária , Cilióforos/classificação , Estresse Oxidativo/fisiologia , Água/química , Animais , Catalase/metabolismo , Infecções por Cilióforos/metabolismo , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Concentração de Íons de Hidrogênio , Fígado/enzimologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo
9.
Eur J Gynaecol Oncol ; 31(4): 469-70, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20882899

RESUMO

BACKGROUND: Some ovarian metaplasias may contain bone or osteoid tissue. The most common tumors presenting these alterations are teratomas and mixed mesodermal tumors with heterologous elements. CASE REPORT: We report the case of a woman who, during gynecologic follow-up for chronic anovulation at the age of 31 years, presented a solid ovarian ultrasonographic image with calcifications. After laparoscopy and histological examination it was found to be an isolated ovarian osseous metaplasia. CONCLUSION: A rarely occurring condition, ovarian osseous metaplasia continues to be of uncertain clinical significance.


Assuntos
Ossificação Heterotópica/patologia , Ovário/patologia , Adulto , Feminino , Humanos , Metaplasia
10.
Biometals ; 22(5): 779-92, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19330492

RESUMO

A hydroponic experiment was carried out to characterize the oxidative stress responses of two potato cultivars (Solanum tuberosum L. cvs. Asterix and Macaca) to cadmium (Cd). Plantlets were exposed to four Cd levels (0, 50, 100, 150 and 200 microM) for 7 days. Cd concentration was increased in both roots and shoot. Number of sprouts and roots was not decreased, whereas Cd treatment affected the number of nodal segments. Chlorophyll content and ALA-D activity were decreased in both cultivars, whereas carotenoids content was decreased only in Macaca. Cd caused lipid peroxidation in roots and shoot of both cultivars. Protein oxidation was only verified at the highest Cd level. H(2)O(2) content was increased in roots and shoot of Asterix, and apparently, a compensatory response between roots and shoot of Macaca was observed. SOD activity was inhibited in roots of Asterix at all Cd treatments, whereas in Macaca it was only increased at two highest Cd levels. Shoot SOD activity increased in Asterix and decreased in Macaca. Root CAT activity in Asterix decreased at 100 and 150 microM, whereas in Macaca it decreased only at 50 microM. Shoot CAT activity was decreased in Macaca. Root AsA content in Macaca was not affected, whereas in shoot it was reduced at 100 microM and increased at 200 microM. Cd caused increase in NPSH content in roots and shoot. Our results suggest that Cd induces oxidative stress in both potato cultivars and that of the two cultivars, Asterix showed greater sensitivity to Cd levels.


Assuntos
Cádmio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/metabolismo , Carotenoides/metabolismo , Catalase/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Proteínas/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Superóxido Dismutase/metabolismo
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