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1.
Sci Total Environ ; 804: 150178, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798733

RESUMO

Coral reefs are likely to be exposed to more intense cyclones under climate change. Cyclone impacts are spatially highly variable given complex hydrodynamics, and coral-specific sensitivity to wave impacts. Predicting reef vulnerability to cyclones is critical to management but requires high resolution environmental data that are difficult to obtain over broad spatial scales. Using 30m-resolution wave modelling, we tested cyclonic and non-cyclonic wave metrics as predictors of coral damage on 22 reefs after severe cyclone Ita impacted the northern Great Barrier Reef, Australia in 2014. Analyses of coral cover change accounting for the type of coral along a gradient of vulnerability to wave damage (e.g., massive, branching, Acroporids) excluded cyclone-generated surface wave metrics (derived from wave height) as important predictors. Increased bottom stress wave environment (near-bed wave orbital velocity) due to Ita (Ita-Ub) explained spatial patterns of 17% to 46% total coral cover loss only when the initial abundance of Acroporids was accounted for, and only when exceeding 35% cover. Greater coral losses occurred closer to the cyclone path irrespective of coral type. Massive and encrusting corals, however, had losses exacerbated in higher non-cyclonic bottom-wave energy environments (nc-Ub). The effect of community composition on structural vulnerability to wave damage was more important predicting damage that the magnitude of the cyclone-generated waves, especially when reefs are surveyed well beyond where damaging waves are expected to occur. Exposure to Ita-Ub was greater in typically high nc-Ub environments with relatively low cover of the most fragile morphologies explaining why these were the least affected overall. We reveal that the common surface-wave metrics of cyclone intensity may not always be able to predict spatial impacts and conclude that reef vulnerability assessments need to account for chronic wave patterns and differences in community composition in order to provide predictive tools for future conservation and restoration.


Assuntos
Antozoários , Tempestades Ciclônicas , Animais , Benchmarking , Mudança Climática , Recifes de Corais , Ecossistema
2.
Rev. chil. pediatr ; 83(2): 170-174, abr. 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-639753

RESUMO

Neuroblastoma is predominantly a tumor of early childhood, most cases occur in children under 5 years old. It originates in the adrenal gland and paravertebral ganglion cells (neural crest-derived), being the most common an extracranial solid tumor in children. It is characteristic a spontaneous regression, However in some cases it shows progression and dissemination to other organs. Objetive: To show a neuroblastoma in adolescence, with poor response to chemotherapy and radiotherapy, requiring surgery treatment. Clinical case: A 16 y.o. Female patient, previously asymptomatic, who after a body temperature rise up to 39 ° C, was found to have a tumor in the right hemithorax. Biopsy was compatible with neuroblastoma. Surgical removal of a large 20 x 19 cm tumor was achieved, the only complication presented 10 days postop was recurrent pneumothorax. Conclusion: Despite little or no response to standard treatment, surgical resection of this large tumor achieved complete remission for this patient.


El neuroblastoma es predominantemente un tumor de la infancia temprana que en la mayoría de los casos se presenta en menores de 5 años. Se origina en la glándula suprarrenal y células ganglionares paravertebrales (derivadas de la cresta neural), siendo el tumor sólido extracraneal más común en pediatría, presenta regresión espontánea en algunos casos y en otros progresión y diseminación a otros órganos. Objetivo: Analizar el caso de una adolescente portadora de un neuroblastoma resistente a quimioterapia y radioterapia, que requiere tratamiento quirúrgico. Caso clínico: Paciente asintomática, edad 16 años, que a raíz de alza febril se le detecta un tumor en hemitórax derecho. La biopsia fue compatible con un neuroblastoma. Se realizo la extirpación quirúrgica de un gran tumor con diámetro de 20 cm x 19 cm. A los 10 días se complica con neumotórax recidivante. Conclusión: A pesar de la poca o nula respuesta a las armas terapéuticas habituales: quimioterapia y radioterapia, la cirugía logró la resección del tumor torácico con remisión completa.


Assuntos
Humanos , Feminino , Adolescente , Neoplasias Torácicas/cirurgia , Neuroblastoma/cirurgia , Neoplasias Torácicas/diagnóstico , Neoplasias Torácicas/tratamento farmacológico , Neoplasias Torácicas/radioterapia , Neuroblastoma/diagnóstico , Neuroblastoma/tratamento farmacológico , Neuroblastoma/radioterapia , Resultado do Tratamento
3.
Rev. biol. trop ; 53(supl.1): 55-60, maio 2005. ilus
Artigo em Inglês | LILACS | ID: lil-456495

RESUMO

The use of chemical pesticides and herbicides has increased environmental pollution and affected ichthyofauna in the watersheds where they are used.We studied the effect of an herbicide, triazine, on the kidneys of two species (Caquetaia kraussii and Colossoma macropomum )widely found in Caribbean and South American rivers.In Venezuela,these species are abundant and have a high aquaculture potential because they may be cultured and reproduced in captivity.Four kidney samples from juveniles of each species exposed to the herbicide were examined by Transmission Electron Microscopy.Kidney tubule alterations included loss of plasmalemma and cell interdigitations, misshaped mitochondria,decrease in rough endoplasmic reticulum and free polysomes,and the presence of autophagic vacuoles and primary lysosomes.These alterations at the cellular level may explain fish behaviour in terms of kidney tubule pathology,and relative amounts and conditions of organelles within affected cells


Assuntos
Animais , Atrazina/toxicidade , Pesqueiros , Peixes , Herbicidas/toxicidade , Rim/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Atrazina/análise , Biomarcadores/análise , Ciclídeos , Herbicidas/análise , Túbulos Renais/química , Túbulos Renais/efeitos dos fármacos , Rim/química , Rim/ultraestrutura , Mitocôndrias/química , Mitocôndrias/efeitos dos fármacos , Venezuela
4.
Rev Biol Trop ; 53 Suppl 1: 55-60, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-17465144

RESUMO

The use of chemical pesticides and herbicides has increased environmental pollution and affected ichthyofauna in the watersheds where they are used. We studied the effect of an herbicide, triazine, on the kidneys of two species (Caquetaia kraussii and Colossomna macropomum) widely found in Caribbean and South American rivers. In Venezuela, these species are abundant and have a high aquaculture potential because they may be cultured and reproduced in captivity. Four kidney samples from juveniles of each species exposed to the herbicide were examined by Transmission Electron Microscopy. Kidney tubule alterations included loss of plasmalemma and cell interdigitations, misshaped mitochondria, decrease in rough endoplasmic reticulum and free polysomes, and the presence of autophagic vacuoles and primary lysosomes. These alterations at the cellular level may explain fish behaviour in terms of kidney tubule pathology, and relative amounts and conditions of organelles within affected cells.


Assuntos
Atrazina/toxicidade , Pesqueiros , Peixes , Herbicidas/toxicidade , Rim/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Atrazina/análise , Biomarcadores/análise , Ciclídeos , Herbicidas/análise , Rim/química , Rim/ultraestrutura , Túbulos Renais/química , Túbulos Renais/efeitos dos fármacos , Mitocôndrias/química , Mitocôndrias/efeitos dos fármacos , Venezuela
5.
Rev. biol. trop ; 48(Supl.1): 145-149, dic. 2000.
Artigo em Espanhol | LILACS | ID: lil-503268

RESUMO

The use of Artemia salina nauplii as live food has significantly aided culture of commercial fish and shrimps in recent years. However, reported deficiencies in the nutritional value of some strains originated the study of freshwater fairy shrimps as an alternative to Artemia. This study presents cyst biometry for Dendrocephalus geayi and D. spartaenovae (Anostraca: Thamnocephalidae), and the effects of some physicochemical variables on cyst hatching. The biometric characteristics of D. geayi and D. spartaenovae are within the size range of commercial Artemia strains. Favorable conditions to hatch D. geayi are 30 degrees C and conductivity near that of distilled water (<5 micromhos). For D. spartaenovae, these conditions are 28 degrees C and 280 micromhos. A very low salinity such as 1 per thousand inhibits hatching in both species.


Assuntos
Animais , Feminino , Ração Animal , Anostraca/crescimento & desenvolvimento , Aquicultura/métodos , Peixes , Biometria , Valor Nutritivo
6.
Rev Biol Trop ; 48 Suppl 1: 145-9, 2000 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-15266802

RESUMO

The use of Artemia salina nauplii as live food has significantly aided culture of commercial fish and shrimps in recent years. However, reported deficiencies in the nutritional value of some strains originated the study of freshwater fairy shrimps as an alternative to Artemia. This study presents cyst biometry for Dendrocephalus geayi and D. spartaenovae (Anostraca: Thamnocephalidae), and the effects of some physicochemical variables on cyst hatching. The biometric characteristics of D. geayi and D. spartaenovae are within the size range of commercial Artemia strains. Favorable conditions to hatch D. geayi are 30 degrees C and conductivity near that of distilled water (<5 micromhos). For D. spartaenovae, these conditions are 28 degrees C and 280 micromhos. A very low salinity such as 1 per thousand inhibits hatching in both species.


Assuntos
Ração Animal , Anostraca/crescimento & desenvolvimento , Aquicultura/métodos , Peixes , Animais , Biometria , Feminino , Valor Nutritivo
7.
Pediatr Surg Int ; 11(8): 554-8, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24057848

RESUMO

Ureteropelvic junction (UPJ) obstruction is the most common urinary tract obstruction in children. Maternal ultrasonography has resulted in early diagnosis of an increasing number of neonatal cases, allowing repair of hydronephrotic kidneys before complications occur. We favor early treatment of congenital hydronephrosis, which should be performed prior to 6 months of age based on evidence of UPJ obstruction, increased pyelocaliceal dilatation, parenchymal thinning, contralateral normal kidney hypertrophy, and functional deterioration. One should not wait for evidence of progressive renal damage before making a diagnosis of obstruction. This therapeutic approach is supported by a review of the most relevant literature published on the subject and our clinical experience. None of the standard tests for measuring obstruction are ideal; hence, we recommend that the results of the different diagnostic procedures for UPJ obstruction should be examined collectively.

8.
Genomics ; 29(2): 512-25, 1995 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-8666402

RESUMO

Physical mapping of human chromosomes at a resolution of 100 kb to 1 Mb will provide important reagents for gene identification and framework templates for ultimately determining the complete DNA sequence. Sequence-tagged site (STS) content mapping, coupled with large fragment cloning in yeast artificial chromosomes, provides an efficient mechanism for producing first-generation, low-resolution maps of human chromosomes. Previously, we produced a set of standardized STSs for human chromosome 11 regionally localized by fluorescence in situ hybridization or somatic cell hybrid analysis. In this paper, we used these as well as other STS content, and identify 109 islands spanning an estimated 218 Mb on the 126-Mb chromosome. Since about 62% of the islands contain markers ordered on chromosome 11 by genetic or radiation hybrid analysis, this data set represents a first-order approximation of a physical map of human chromosome 11. This set of clones, contigs, and associated STSs will provide the material for the production of a continuous overlapping set of YACs as well for high-resolution physical mapping based upon sampled and complete DNA sequencing.


Assuntos
Cromossomos Humanos Par 11 , Sitios de Sequências Rotuladas , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Artificiais de Levedura , Clonagem Molecular , DNA/química , DNA/genética , Primers do DNA , Biblioteca Gênica , Marcadores Genéticos , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético
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