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1.
Microorganisms ; 11(12)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38138095

RESUMO

Actinobacteria are important sources of antibiotics and have been found repeatedly in coral core microbiomes, suggesting this bacterial group plays important functional roles tied to coral survival. However, to unravel coral-actinobacteria ecological interactions and discover new antibiotics, the complex challenges that arise when isolating symbiotic actinobacteria must be overcome. Moreover, by isolating unknown actinobacteria from corals, novel biotechnological applications may be discovered. In this study, we compared actinobacteria recovery from coral samples between two widely known methods for isolating actinobacteria: dry stamping and heat shock. We found that dry stamping was at least three times better than heat shock. The assembly of isolated strains by dry stamping was unique for each species and consistent across same-species samples, highlighting that dry stamping can be reliably used to characterize coral actinobacteria communities. By analyzing the genomes of the closest related type strains, we were able to identify several functions commonly found among symbiotic organisms, such as transport and quorum sensing. This study provides a detailed methodology for isolating coral actinobacteria for ecological and biotechnological purposes.

2.
Pest Manag Sci ; 79(1): 368-380, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36165215

RESUMO

BACKGROUND: Metabolic reconfiguration in plants is a hallmark response to insect herbivory that occurs in the attack site and systemically in undamaged tissues. Metabolomic systemic responses can occur rapidly while the herbivore is still present and may persist in newly developed tissue to counterattack future herbivore attacks. This study analyzed the metabolic profile of local and newly developed distal (systemic) leaves of husk tomato (Physalis philadelphica) plants after whitefly Trialeurodes vaporariorum infestation. In addition, the effect of these metabolomic adjustments on whitefly oviposition and development was evaluated. RESULTS: Our results indicate that T. vaporariorum infestation induced significant changes in husk tomato metabolic profiles, not only locally in infested leaves, but also systemically in distal leaves that developed after infestation. The distinctive metabolic profile produced in newly developed leaves affected whitefly nymphal development but did not affect female oviposition, suggesting that changes driven by whitefly herbivory persist in the young leaves that developed after the infestation event to avoid future herbivore attacks. CONCLUSIONS: This report contributes to further understanding the plant responses to sucking insects by describing the metabolic reconfiguration in newly developed, undamaged systemic leaf tissues of husk tomato plants after whitefly infestation. © 2022 Society of Chemical Industry.


Assuntos
Hemípteros , Physalis , Animais , Metabolômica , Folhas de Planta
3.
Front Plant Sci ; 13: 920881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003821

RESUMO

To ensure food security given the current scenario of climate change and the accompanying ecological repercussions, it is essential to search for new technologies and tools for agricultural production. Microorganism-based biostimulants are recognized as sustainable alternatives to traditional agrochemicals to enhance and protect agricultural production. Marine actinobacteria are a well-known source of novel compounds for biotechnological uses. In addition, former studies have suggested that coral symbiont actinobacteria may support co-symbiotic photosynthetic growth and tolerance and increase the probability of corals surviving abiotic stress. We have previously shown that this activity may also hold in terrestrial plants, at least for the actinobacteria Salinispora arenicola during induced heterologous symbiosis with a wild Solanaceae plant Nicotiana attenuata under in vitro conditions. Here, we further explore the heterologous symbiotic association, germination, growth promotion, and stress relieving activity of S. arenicola in tomato plants under agricultural conditions and dig into the possible associated mechanisms. Tomato plants were grown under normal and saline conditions, and germination, bacteria-root system interactions, plant growth, photosynthetic performance, and the expression of salt stress response genes were analyzed. We found an endophytic interaction between S. arenicola and tomato plants, which promotes germination and shoot and root growth under saline or non-saline conditions. Accordingly, photosynthetic and respective photoprotective performance was enhanced in line with the induced increase in photosynthetic pigments. This was further supported by the overexpression of thermal energy dissipation, which fine-tunes energy use efficiency and may prevent the formation of reactive oxygen species in the chloroplast. Furthermore, gene expression analyses suggested that a selective transport channel gene, SlHKT1,2, induced by S. arenicola may assist in relieving salt stress in tomato plants. The fine regulation of photosynthetic and photoprotective responses, as well as the inhibition of the formation of ROS molecules, seems to be related to the induced down-regulation of other salt stress response genes, such as SlDR1A-related genes or SlAOX1b. Our results demonstrate that the marine microbial symbiont S. arenicola establishes heterologous symbiosis in crop plants, promotes growth, and confers saline stress tolerance. Thus, these results open opportunities to further explore the vast array of marine microbes to enhance crop tolerance and food production under the current climate change scenario.

4.
Front Plant Sci ; 13: 893095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812979

RESUMO

The evolution of Crassulacean acid metabolism (CAM) by plants has been one of the most successful strategies in response to aridity. On the onset of climate change, expanding the use of water efficient crops and engineering higher water use efficiency into C3 and C4 crops constitute a plausible solution for the problems of agriculture in hotter and drier environments. A firm understanding of CAM is thus crucial for the development of agricultural responses to climate change. Computational models on CAM can contribute significantly to this understanding. Two types of models have been used so far. Early CAM models based on ordinary differential equations (ODE) reproduced the typical diel CAM features with a minimal set of components and investigated endogenous day/night rhythmicity. This line of research brought to light the preponderant role of vacuolar malate accumulation in diel rhythms. A second wave of CAM models used flux balance analysis (FBA) to better understand the role of CO2 uptake in flux distribution. They showed that flux distributions resembling CAM metabolism emerge upon constraining CO2 uptake by the system. We discuss the evolutionary implications of this and also how CAM components from unrelated pathways could have integrated along evolution.

5.
Int J Mol Sci ; 22(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34830402

RESUMO

Lipids are closely associated with brain structure and function. However, the potential changes in the lipidome induced by aging remain to be elucidated. In this study, we used chromatographic techniques and a mass spectrometry-based approach to evaluate age-associated changes in the lipidome of the frontal cortex and cerebellum obtained from adult male Wistar rats (8 months), aged male Wistar rats (26 months), and aged male Wistar rats submitted to a methionine restriction diet (MetR)-as an anti-aging intervention-for 8 weeks. The outcomes revealed that only small changes (about 10%) were observed in the lipidome profile in the cerebellum and frontal cortex during aging, and these changes differed, in some cases, between regions. Furthermore, a MetR diet partially reversed the effects of the aging process. Remarkably, the most affected lipid classes were ether-triacylglycerols, diacylglycerols, phosphatidylethanolamine N-methylated, plasmalogens, ceramides, and cholesterol esters. When the fatty acid profile was analyzed, we observed that the frontal cortex is highly preserved during aging and maintained under MetR, whereas in the cerebellum minor changes (increased monounsaturated and decreased polyunsaturated contents) were observed and not reversed by MetR. We conclude that the rat cerebellum and frontal cortex have efficient mechanisms to preserve the lipid profile of their cell membranes throughout their adult lifespan in order to maintain brain structure and function. A part of the small changes that take place during aging can be reversed with a MetR diet applied in old age.


Assuntos
Envelhecimento/genética , Lobo Frontal/metabolismo , Lipídeos/genética , Metionina/metabolismo , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Cerebelo/metabolismo , Cerebelo/patologia , Cromatografia , Lobo Frontal/patologia , Humanos , Lipidômica/normas , Espectrometria de Massas , Estresse Oxidativo/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo
6.
Front Plant Sci ; 11: 648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523601

RESUMO

From their chemical nature to their ecological interactions, coral reef ecosystems have a lot in common with highly productive terrestrial ecosystems. While plants are responsible for primary production in the terrestrial sphere, the photosynthetic endosymbionts of corals are the key producers in reef communities. As in plants, coral microbiota have been suggested to stimulate the growth and physiological performance of the photosynthetic endosymbionts that provide energy sources to the coral. Among them, actinobacteria are some of the most probable candidates. To explore the potential of coral actinobacteria as plant biostimulants, we have analyzed the activity of Salinispora strains isolated from the corals Porites lobata and Porites panamensis, which were identified as Salinispora arenicola by 16S rRNA sequencing. We evaluated the effects of this microorganism on the germination, plant growth, and photosynthetic response of wild tobacco (Nicotiana attenuata) under a saline regime. We identified protective activity of this actinobacteria on seed germination and photosynthetic performance under natural light conditions. Further insights into the possible mechanism showed an endophytic-like symbiosis between N. attenuata roots and S. arenicola and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity by S. arenicola. We discuss these findings in the context of relevant ecological and physiological responses and biotechnological potential. Overall, our results will contribute to the development of novel biotechnologies to cope with plant growth under saline stress. Our study highlights the importance of understanding marine ecological interactions for the development of novel, strategic, and sustainable agricultural solutions.

7.
Plant Cell Environ ; 40(7): 1039-1056, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27925291

RESUMO

Herbivory-induced changes in photosynthesis have been documented in many plant species; however, the complexity of photosynthetic regulation and analysis has thwarted progress in understanding the mechanism involved, particularly those elicited by herbivore-specific elicitors. Here, we analysed the early photosynthetic gas exchange responses in Nicotiana attenuata plants after wounding and elicitation with Manduca sexta oral secretions and the pathways regulating these responses. Elicitation with M. sexta oral secretions rapidly decreased photosynthetic carbon assimilation (AC ) in treated and systemic (untreated, vascularly connected) leaves, which were associated with changes in stomatal conductance, rather than with changes in Rubisco activity and 1-5 ribulose-1,5-bisphosphate turnover. Phytohormone profiling and gas exchange analysis of oral secretion-elicited transgenic plants altered in phytohormone regulation, biosynthesis and perception, combined with micrografting techniques, revealed that the local photosynthetic responses were mediated by 12-oxo-phytodienoic acid, while the systemic responses involved interactions among jasmonates, cytokinins and abscisic acid signalling mediated by mitogen-activated protein kinase 4. The analysis also revealed a role for cytokinins interacting with mitogen-activated protein kinase 4 in CO2 -mediated stomatal regulation. Hence, oral secretions, while eliciting jasmonic acid-mediated defence responses, also elicit 12-oxo-phytodienoic acid-mediated changes in stomatal conductance and AC , an observation illustrating the complexity and economy of the signalling that regulates defence and carbon assimilation pathways in response to herbivore attack.


Assuntos
Carbono/metabolismo , Citocininas/metabolismo , Herbivoria/fisiologia , Nicotiana/fisiologia , Estômatos de Plantas/fisiologia , Animais , Ácidos Graxos Insaturados/metabolismo , Manduca/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Ribulose-Bifosfato Carboxilase/metabolismo
8.
New Phytol ; 208(2): 519-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26017581

RESUMO

Plant invertases are sucrolytic enzymes that are essential for the regulation of carbohydrate metabolism and source-sink relationships. While their activity has been well documented during abiotic and biotic stresses, the role of proteinaceous invertase inhibitors in regulating these changes is unknown. Here, we identify a putative Nicotiana attenuata cell wall invertase inhibitor (NaCWII) which is strongly up-regulated in a jasmonate (JA)-dependent manner following simulated attack by the specialist herbivore Manduca sexta. To understand the role of NaCWII in planta, we silenced its expression by RNA interference and measured changes in primary and secondary metabolism and plant growth following simulated herbivory. NaCWII-silenced plants displayed a stronger depletion of carbohydrates and a reduced capacity to increase secondary metabolite pools relative to their empty vector control counterparts. This coincided with the attenuation of herbivore-induced CWI inhibition and growth suppression characteristic of wild-type plants. Together our findings suggest that NaCWII may act as a regulatory switch located downstream of JA accumulation which fine-tunes the plant's balance between growth and defense metabolism under herbivore attack. Although carbohydrates are not typically viewed as key factors in plant growth and defense, our study shows that interfering with their catabolism strongly influences plant responses to herbivory.


Assuntos
Parede Celular/metabolismo , Herbivoria , Manduca/fisiologia , Nicotiana/crescimento & desenvolvimento , Nicotiana/parasitologia , Proteínas de Plantas/metabolismo , Metabolismo Secundário , Sequência de Aminoácidos , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Clonagem Molecular , Ciclopentanos/farmacologia , DNA Complementar/genética , Inativação Gênica/efeitos dos fármacos , Herbivoria/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/fisiologia , Manduca/efeitos dos fármacos , Dados de Sequência Molecular , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/química , Metabolismo Secundário/efeitos dos fármacos , Nicotiana/citologia , Nicotiana/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , beta-Frutofuranosidase/antagonistas & inibidores
9.
Exp Cell Res ; 335(1): 39-50, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978974

RESUMO

According to the multifactorial model of cervical cancer (CC) causation, it is now recognized that other modifications, in addition to Human papillomavirus (HPV) infection, are necessary for the development of this neoplasia. Among these, it has been proposed that a dysregulation of the WNT pathway might favor malignant progression of HPV-immortalized keratinocytes. The aim of this study was to identify components of the WNT pathway differentially expressed in CC vs. non-tumorigenic, but immortalized human keratinocytes. Interestingly, WNT7A expression was found strongly downregulated in cell lines and biopsies derived from CC. Restoration of WNT7A in CC-derived cell lines using a lentiviral gene delivery system or after adding a recombinant human protein decreases cell proliferation. Likewise, WNT7A silencing in non-tumorigenic cells markedly accelerates proliferation. Decreased WNT7A expression was due to hypermethylation at particular CpG sites. To our knowledge, this is the first study reporting reduced WNT7A levels in CC-derived cells and that ectopic WNT7A restoration negatively affects cell proliferation and migration.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , Metilação de DNA/genética , Neoplasias do Colo do Útero/genética , Proteínas Wnt/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Meios de Cultivo Condicionados/farmacologia , Feminino , Células HeLa , Humanos , Interferência de RNA , RNA Interferente Pequeno , Proteínas Recombinantes/farmacologia , Neoplasias do Colo do Útero/metabolismo , Proteínas Wnt/biossíntese , Proteínas Wnt/farmacologia , Via de Sinalização Wnt/genética
10.
J Exp Bot ; 66(16): 4873-84, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25998904

RESUMO

Cytokinins (CKs) are well-established as important phytohormonal regulators of plant growth and development. An increasing number of studies have also revealed the function of these hormones in plant responses to biotic and abiotic stresses. While the function of certain CK classes, including trans-zeatin and isopentenyladenine-type CKs, have been studied in detail, the role of cis-zeatin-type CKs (cZs) in plant development and in mediating environmental interactions is less well defined. Here we provide a comprehensive summary of the current knowledge about abundance, metabolism and activities of cZs in plants. We outline the history of their analysis and the metabolic routes comprising cZ biosynthesis and degradation. Further we provide an overview of changes in the pools of cZs during plant development and environmental interactions. We summarize studies that investigate the role of cZs in regulating plant development and defence responses to pathogen and herbivore attack and highlight their potential role as 'novel' stress-response markers. Since the functional roles of cZs remain largely based on correlative data and genetic manipulations of their biosynthesis, inactivation and degradation are few, we suggest experimental approaches using transgenic plants altered in cZ levels to further uncover their roles in plant growth and environmental interactions and their potential for crop improvement.


Assuntos
Cadeia Alimentar , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Fenômenos Fisiológicos Vegetais , Zeatina/metabolismo , Herbivoria , Desenvolvimento Vegetal
11.
New Phytol ; 207(3): 645-58, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25919325

RESUMO

Herbivore attack elicits changes in cytokinins (CKs), but how these changes influence defense signaling remains poorly described. We investigated the influence of the CK pathway on the well-described inducible defense pathways of Nicotiana attenuata in response to wounding with and without elicitors from the specialist herbivore Manduca sexta. CK pathway manipulation often suffers from substantial side effects on plant growth and development. We therefore used multiple manipulation tools including spray application of CKs, chemically-inducible expression of the CK biosynthesis enzyme isopentenyltransferase, and transient and constitutive RNAi-mediated gene silencing of CK receptors to resolve the function of CKs in plant defense. The results demonstrated that CK concentrations in leaves and perception through CHASE-DOMAIN CONTAINING HIS KINASE 2 (NaCHK2) and NaCHK3 were important for the accumulation of jasmonic acid (JA) and phenolamides and proteinase inhibitor activity. By contrast, the CK pathway did not promote the accumulation of the active JA-isoleucine conjugate and negatively regulated the release of specific green leaf volatile esters. Interestingly, CK signaling also promotes the systemic phenolamide accumulation. We conclude that the CK pathway is an important regulator of herbivory-inducible defense signaling and chemistry, which expands its reported participation in adjusting a plant's physiology to abiotic and biotic stress responses.


Assuntos
Citocininas/metabolismo , Herbivoria , Nicotiana/imunologia , Nicotiana/fisiologia , Transdução de Sinais , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Nicotiana/genética
12.
J Integr Plant Biol ; 57(2): 198-212, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24924599

RESUMO

Nearly half a century ago insect herbivores were found to induce the formation of green islands by manipulating cytokinin (CK) levels. However, the response of the CK pathway to attack by chewing insect herbivores remains unclear. Here, we characterize the CK pathway of Nicotiana attenuata (Torr. ex S. Wats.) and its response to wounding and perception of herbivore-associated molecular patterns (HAMPs). We identified 44 genes involved in CK biosynthesis, inactivation, degradation, and signaling. Leaf wounding rapidly induced transcriptional changes in multiple genes throughout the pathway, as well as in the levels of CKs, including isopentenyladenosine and cis-zeatin riboside; perception of HAMPs present in the oral secretions (OS) of the specialist herbivore Manduca sexta amplified these responses. The jasmonate pathway, which triggers many herbivore-induced processes, was not required for these HAMP-triggered changes, but rather suppressed the CK responses. Interestingly CK pathway changes were observed also in systemic leaves in response to wounding and OS application indicating a role of CKs in mediating long distance systemic processes in response to herbivory. Since wounding and grasshopper OS elicited similar accumulations of CKs in Arabidopsis thaliana L., we propose that CKs are integral components of wounding and HAMP-triggered responses in many plant species.


Assuntos
Citocininas/metabolismo , Herbivoria/fisiologia , Nicotiana/fisiologia , Transdução de Sinais , Aminoácidos/metabolismo , Animais , Ciclopentanos/farmacologia , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Manduca/fisiologia , Oxilipinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Nicotiana/genética
13.
BMC Cancer ; 12: 60, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22313908

RESUMO

BACKGROUND: WNT7a, a member of the Wnt ligand family implicated in several developmental processes, has also been reported to be dysregulated in some types of tumors; however, its function and implication in oncogenesis is poorly understood. Moreover, the expression of this gene and the role that it plays in the biology of blood cells remains unclear. In addition to determining the expression of the WNT7A gene in blood cells, in leukemia-derived cell lines, and in samples of patients with leukemia, the aim of this study was to seek the effect of this gene in proliferation. METHODS: We analyzed peripheral blood mononuclear cells, sorted CD3 and CD19 cells, four leukemia-derived cell lines, and blood samples from 14 patients with Acute lymphoblastic leukemia (ALL), and 19 clinically healthy subjects. Reverse transcription followed by quantitative Real-time Polymerase chain reaction (qRT-PCR) analysis were performed to determine relative WNT7A expression. Restoration of WNT7a was done employing a lentiviral system and by using a recombinant human protein. Cell proliferation was measured by addition of WST-1 to cell cultures. RESULTS: WNT7a is mainly produced by CD3 T-lymphocytes, its expression decreases upon activation, and it is severely reduced in leukemia-derived cell lines, as well as in the blood samples of patients with ALL when compared with healthy controls (p ≤0.001). By restoring WNT7A expression in leukemia-derived cells, we were able to demonstrate that WNT7a inhibits cell growth. A similar effect was observed when a recombinant human WNT7a protein was used. Interestingly, restoration of WNT7A expression in Jurkat cells did not activate the canonical Wnt/ß-catenin pathway. CONCLUSIONS: To our knowledge, this is the first report evidencing quantitatively decreased WNT7A levels in leukemia-derived cells and that WNT7A restoration in T-lymphocytes inhibits cell proliferation. In addition, our results also support the possible function of WNT7A as a tumor suppressor gene as well as a therapeutic tool.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Linfócitos T/metabolismo , Proteínas Wnt/metabolismo , Adulto , Idoso , Análise de Variância , Antígenos CD19/imunologia , Western Blotting , Complexo CD3/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Perfilação da Expressão Gênica , Humanos , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Proteínas Recombinantes/farmacologia , Linfócitos T/imunologia , Proteínas Wnt/genética , Proteínas Wnt/farmacologia
14.
Rev. méd. Chile ; 129(9): 1079-1084, sept. 2001. tab
Artigo em Espanhol | LILACS | ID: lil-302041

RESUMO

This paper analyses the information of the Ministry of Health on gallbladder cancer mortality in Chile since 1997. It becomes evident that the decrease in mortality in the last two years is only apparent and due to a statistical artifact, caused by the non validated application of the Tenth International Classification of Diseases. There is a consensus that one of the causes for an increase in gallbladder cancer in a specific country is a decrease in cholecystectomy rates. This association has been clearly demonstrated in Chile, but no control program for gallbladder cancer has been devised, considering that an early cholecystectomy is a good secondary prevention measure


Assuntos
Humanos , Masculino , Feminino , Neoplasias da Vesícula Biliar , Colecistectomia , Chile , Vírus da Estomatite Vesicular Indiana , Neoplasias da Vesícula Biliar , Ducto Colédoco , Doenças do Ducto Colédoco/epidemiologia , Estatísticas Hospitalares
15.
Rev. méd. Chile ; 127(4): 485-92, abr. 1999. tab, graf
Artigo em Espanhol | LILACS | ID: lil-243922

RESUMO

Background: There is evidence to postulate that undernotification is the reason for the great decrease in the reported incidence of hydatidosis in Chile. Aim: To develop and propose a method to assess the notification of transmissible diseases, based on observed lethality and hospital discharges. Material and methods: Human hydatidosis in the period 1985-1994 was used as a model to develop the method. Official reports and mortality were analyzed first, determining the first lethality rate. A second lethality rate was calculated based on hospital discharges and a third, based on all Chilean surgical series published in the last two decades. Adjusting official notification of lethality to the true lethality according to surgical series, the number of unreported cases was calculated and the true incidence of hydatidosis was calculated, summing these cases to the official notification. Results: According to this method, the real rates of human hydatidosis in the period 1985-1994, would fluctuate between 6.5 and 11.4 per 100,000. This figure is four times higher than the official notification in the analysed period. Conclusions: The correction of under notification based on hospital discharges, with or without correction for repeated hospital admissions, or real mortality of surgical series gave similar results, suggesting that both methods are correct


Assuntos
Humanos , Equinococose/epidemiologia , Notificação de Doenças/estatística & dados numéricos , Chile/epidemiologia , Incidência , Equinococose/cirurgia , Equinococose/mortalidade , Admissão do Paciente/estatística & dados numéricos , Notificação de Doenças/métodos
16.
Rev. méd. Chile ; 127(2): 202-5, feb. 1999.
Artigo em Espanhol | LILACS | ID: lil-243780

RESUMO

Acetaminophen hepatotoxicity in a teenager with excessive alcohol intake We report a 12 years old male with a history of excessive alcohol intake, that developed a severe liver failure after the use of acetaminophen in therapeutic doses. He presented with encephalopathy, jaundice, fever and an upper gastrointestinal bleeding. Serum aspartate aminotransferase values were 5 250 IU/L. The patient received supportive care and oral corticosteroids, remained severely compromised for 72 hours and had a good evolution thereafter. The association of acetaminophen use and excessive alcohol intake in a patient who developed an acute hepatic failure and the absence of serological evidence of hepatitis A or B viral infection, support the diagnosis of drug induced liver failure


Assuntos
Humanos , Masculino , Criança , Falência Hepática Aguda/induzido quimicamente , Acetaminofen/intoxicação , Convulsões/etiologia , Evasão Escolar , Falência Hepática Aguda/complicações , Falência Hepática Aguda/tratamento farmacológico , Corticosteroides/uso terapêutico , Diazepam/uso terapêutico , Hipersensibilidade a Drogas , Alcoolismo/complicações , Automedicação/efeitos adversos
17.
Rev. méd. Chile ; 126(11): 1301-10, nov. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-243721

RESUMO

Background: Gallbladder carcinoma is the first cause of cancer deaths among chilean women. The few cytogenetic studies performed in these tumors have not found specific or primary chromosome abnormalities. Also, no relationships with specific oncogenes have been found. Aim: To perform cytogenetic studies in gallbladder carcinoma. Material and Methods: A chromosomal study and measurement of dna content, was performed in 38 samples of advanced gallbladder carcinoma and in 40 samples of gallbladders without malignant changes. Results: Hyperploidies were found in the karyotype of 15 carcinomas (near triploidies and near teraploidies). These findings were confirmed in the cytometric study. Multiple structural chromosome abnormalities were found in 11 and 15 samples, such as translocations, deletions, inversions, isochromosomes, rings and markers. Some chromosome alterations such as interstitial deletion of chromosome 4, deletion of distal region of chromosome 12, deletion of distal segment of the short arm of chromosome 17 with a fracture point in p12 and rearrangement of chromosome 6 were repeated in 2 or more cases. Conclusions: Hyperploidies in gallbladder carcinoma are an alteration that appears in advanced stages of the tumor. Chromosomal abnormalities may be a primary or specific alteration of this tumor, whose prognostic or diagnostic role should be explored. There are ongogenes related to some mentioned chromosomal fracture points, that should be explored with molecular techniques


Assuntos
Humanos , Aberrações Cromossômicas/diagnóstico , Neoplasias da Vesícula Biliar/genética , Ploidias , Adenocarcinoma/patologia , Citogenética/métodos , Citometria de Fluxo/métodos
18.
Rev. méd. Chile ; 126(10): 1247-54, oct. 1998.
Artigo em Espanhol | LILACS | ID: lil-242711

RESUMO

This article reviews the role of nutrition in the incidence of gallstones. The epidemiological situation of gallbladder disease has wide worldwide geographical variations, being Pima Indians and the Chileans the most affected populations. The main nutritional risk factor is obesity. Other risk are serum cholesterol and triglyceride levels, unbalanced and excessive caloric intake, fasting periods of more than eight hours, hypocaloric diets of less than 700 Kcal/day, specially in obese subjects and parenteral nutrition lasting more than two weeks. The main conclusion of this revision is that nutritional behaviors of the population must be improved through public health programs, to reduce the incidence of obesity and related nutritional imbalances


Assuntos
Humanos , Masculino , Feminino , Obesidade/complicações , Cálculos da Bexiga Urinária/etiologia , Chile/epidemiologia , Fatores de Risco , Hipercolesterolemia/complicações , Cálculos da Bexiga Urinária/epidemiologia , Características de Residência/estatística & dados numéricos , Comportamento Alimentar
19.
Rev. chil. cir ; 50(5): 479-85, oct. 1998. graf
Artigo em Espanhol | LILACS | ID: lil-242644

RESUMO

Este tipo de estudio tiene especial interés para Chile dado el notable incremento de este cáncer, el cual se mantiene hasta la actualidad (1.628 muertes y tasa de 11,5 por 100.000 en 1995). La especie usada fue el hamster (Mesocricetus auratus) y un carcinógeno, la dimetil nitrosamina, fue administrado por vía oral, en una dosis establecida. Se formaron 3 grupos de 20 animales cada uno, por un tiempo que alcanza los seis meses. El primer grupo se organizó como control. El grupo control ha tenido muertes espontáneas después del primer año de vida y no ha mostrado ningún cáncer vesicular. Los otros dos grupos tienen muy poco tiempo de evolución para extraer conclusiones en relación a cáncer, pero habría un efecto protector de los antioxidantes


Assuntos
Animais , Cricetinae , Dimetilnitrosamina/farmacologia , Neoplasias da Vesícula Biliar/induzido quimicamente , Antioxidantes/farmacologia , Estudos de Casos e Controles , Ingestão de Líquidos , Neoplasias da Vesícula Biliar/prevenção & controle
20.
Rev. méd. Chile ; 126(8): 1010-8, ago. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-232948

RESUMO

Background: Despite the epidemiological importance and the surveillance programs to detect cervix uterine cancer in Chile, its mortality continues to be high. Aim: To perform an audit of all deaths due to cervix uterine cancer, that occurred in a health service of Santiago during 1995. Material and methods: The clinical records and pathological studies of 46 women, whose death certificates indicated cervix uterine cancer as the cause of death, were audited. Results: In six women, the audit revealed that the cause of death was not a cervix uterine cancer, and they were discarded from further analyses. The higher mortality rate (36/100000) ocurred in women over 64 years old, those living in the poorest community and with less Papanicolaou vaginal smears coverage (La Pintana). The evolution prior to diagnosis was registered in only four women and was of less than one year. Most women consulted in advanced stages of the disease and only 48percent were subjected to some sort of treatment (surgery, radiotherapy or chemotherapy). Mean survival was 3 years and mean age at death was 55.5 years old. There was a great lack of clinical and epidemiological information. In only 13 women information about previous Pap smears was registered. Conclusions: Audit of deaths should be an important component of preventive programs for cervix uterine cancer, and the coverage of Pap smears should be improved


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/mortalidade , Auditoria Médica , Fatores de Risco , Sobreviventes/estatística & dados numéricos , Escolaridade , Atestado de Óbito
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