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1.
J Phycol ; 60(1): 4-14, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37943584

RESUMO

To limit global warming below 2°C by 2100, we must drastically reduce greenhouse gas emissions and additionally remove ~100-900 Gt CO2 from the atmosphere (carbon dioxide removal, CDR) to compensate for unavoidable emissions. Seaweeds (marine macroalgae) naturally grow in coastal regions worldwide where they are crucial for primary production and carbon cycling. They are being considered as a biological method for CDR and for use in carbon trading schemes as offsets. To use seaweeds in carbon trading schemes requires verification that seaweed photosynthesis that fixes CO2 into organic carbon results in CDR, along with the safe and secure storage of the carbon removed from the atmosphere for more than 100 years (sequestration). There is much ongoing research into the magnitude of seaweed carbon storage pools (e.g., as living biomass and as particulate and dissolved organic carbon in sediments and the deep ocean), but these pools do not equate to CDR unless the amount of CO2 removed from the atmosphere as a result of seaweed primary production can be quantified and verified. The draw-down of atmospheric CO2 into seawater is via air-sea CO2 equilibrium, which operates on time scales of weeks to years depending upon the ecosystem considered. Here, we explain why quantifying air-sea CO2 equilibrium and linking this process to seaweed carbon storage pools is the critical step needed to verify CDR by discrete seaweed beds and nearshore and open ocean aquaculture systems prior to their use in carbon trading.


Assuntos
Ecossistema , Alga Marinha , Dióxido de Carbono , Água do Mar , Biomassa
2.
Nat Commun ; 10(1): 5821, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862880

RESUMO

Global climate change has intensified the need to assess the capacity for natural populations to adapt to abrupt shifts in the environment. Reductions in seawater pH constitute a conspicuous global change stressor that is affecting marine ecosystems globally. Here, we quantify the phenotypic and genetic modifications associated with rapid adaptation to reduced seawater pH in the Mediterranean mussel, Mytilus galloprovincialis. We reared a genetically diverse larval population in two pH treatments (pHT 8.1 and 7.4) and tracked changes in the shell-size distribution and genetic variation through settlement. Additionally, we identified differences in the signatures of selection on shell growth in each pH environment. Both phenotypic and genetic data show that standing variation can facilitate adaptation to declines in seawater pH. This work provides insight into the processes underpinning rapid evolution, and demonstrates the importance of maintaining variation within natural populations to bolster species' adaptive capacity as global change progresses.


Assuntos
Aclimatação/genética , Bivalves/fisiologia , Evolução Molecular , Água do Mar/química , Animais , Mudança Climática , Variação Genética , Concentração de Íons de Hidrogênio , Larva , Mar Mediterrâneo , Herança Multifatorial/fisiologia , Fenótipo
3.
Proc Biol Sci ; 285(1893): 20182381, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30963891

RESUMO

Coastal marine ecosystems experience dynamic fluctuations in seawater carbonate chemistry. The importance of this variation in the context of ocean acidification requires knowing what aspect of variability biological processes respond to. We conducted four experiments (ranging from 3 to 22 days) with different variability regimes (pHT 7.4-8.1) assessing the impact of diel fluctuations in carbonate chemistry on the early development of the mussel Mytilus galloprovincialis. Larval shell growth was consistently correlated to mean exposures, regardless of variability regimes, indicating that calcification responds instantaneously to seawater chemistry. Larval development was impacted by timing of exposure, revealing sensitivity of two developmental processes: development of the shell field, and transition from the first to the second larval shell. Fluorescent staining revealed developmental delay of the shell field at low pH, and abnormal development thereof was correlated with hinge defects in D-veligers. This study shows, for the first time, that ocean acidification affects larval soft-tissue development, independent from calcification. Multiple developmental processes additively underpin the teratogenic effect of ocean acidification on bivalve larvae. These results explain why trochophores are the most sensitive life-history stage in marine bivalves and suggest that short-term variability in carbonate chemistry can impact early larval development.


Assuntos
Carbonatos/química , Mytilus/crescimento & desenvolvimento , Água do Mar/química , Animais , Mudança Climática , Concentração de Íons de Hidrogênio , Larva/crescimento & desenvolvimento
4.
Science ; 349(6243): aac4722, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26138982

RESUMO

The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems­and the goods and services they provide­for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario­consistent with the Copenhagen Accord's goal of a global temperature increase of less than 2°C­is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies. Consequently, any new climate regime that fails to minimize ocean impacts would be incomplete and inadequate.


Assuntos
Organismos Aquáticos , Dióxido de Carbono , Ecossistema , Aquecimento Global , Efeito Estufa , Animais , Aquicultura , Saúde , Humanos , Oceanos e Mares , Risco , Viagem
5.
Mol Ecol ; 24(2): 438-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25444080

RESUMO

Corals play a key role in ocean ecosystems and carbonate balance, but their molecular response to ocean acidification remains unclear. The only previous whole-transcriptome study (Moya et al. Molecular Ecology, 2012; 21, 2440) documented extensive disruption of gene expression, particularly of genes encoding skeletal organic matrix proteins, in juvenile corals (Acropora millepora) after short-term (3 d) exposure to elevated pCO2 . In this study, whole-transcriptome analysis was used to compare the effects of such 'acute' (3 d) exposure to elevated pCO2 with a longer ('prolonged'; 9 d) period of exposure beginning immediately post-fertilization. Far fewer genes were differentially expressed under the 9-d treatment, and although the transcriptome data implied wholesale disruption of metabolism and calcification genes in the acute treatment experiment, expression of most genes was at control levels after prolonged treatment. There was little overlap between the genes responding to the acute and prolonged treatments, but heat shock proteins (HSPs) and heat shock factors (HSFs) were over-represented amongst the genes responding to both treatments. Amongst these was an HSP70 gene previously shown to be involved in acclimation to thermal stress in a field population of another acroporid coral. The most obvious feature of the molecular response in the 9-d treatment experiment was the upregulation of five distinct Bcl-2 family members, the majority predicted to be anti-apoptotic. This suggests that an important component of the longer term response to elevated CO2 is suppression of apoptosis. It therefore appears that juvenile A. millepora have the capacity to rapidly acclimate to elevated pCO2 , a process mediated by upregulation of specific HSPs and a suite of Bcl-2 family members.


Assuntos
Aclimatação/genética , Antozoários/genética , Dióxido de Carbono/química , Genes bcl-2 , Proteínas de Choque Térmico/genética , Animais , Antozoários/fisiologia , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Família Multigênica , Estresse Oxidativo/genética , Queensland , Análise de Sequência de RNA , Transcriptoma , Regulação para Cima
6.
Mol Ecol ; 21(10): 2440-54, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22490231

RESUMO

The impact of ocean acidification (OA) on coral calcification, a subject of intense current interest, is poorly understood in part because of the presence of symbionts in adult corals. Early life history stages of Acropora spp. provide an opportunity to study the effects of elevated CO(2) on coral calcification without the complication of symbiont metabolism. Therefore, we used the Illumina RNAseq approach to study the effects of acute exposure to elevated CO(2) on gene expression in primary polyps of Acropora millepora, using as reference a novel comprehensive transcriptome assembly developed for this study. Gene ontology analysis of this whole transcriptome data set indicated that CO(2) -driven acidification strongly suppressed metabolism but enhanced extracellular organic matrix synthesis, whereas targeted analyses revealed complex effects on genes implicated in calcification. Unexpectedly, expression of most ion transport proteins was unaffected, while many membrane-associated or secreted carbonic anhydrases were expressed at lower levels. The most dramatic effect of CO(2) -driven acidification, however, was on genes encoding candidate and known components of the skeletal organic matrix that controls CaCO(3) deposition. The skeletal organic matrix effects included elevated expression of adult-type galaxins and some secreted acidic proteins, but down-regulation of other galaxins, secreted acidic proteins, SCRiPs and other coral-specific genes, suggesting specialized roles for the members of these protein families and complex impacts of OA on mineral deposition. This study is the first exhaustive exploration of the transcriptomic response of a scleractinian coral to acidification and provides an unbiased perspective on its effects during the early stages of calcification.


Assuntos
Antozoários/genética , Calcificação Fisiológica/genética , Dióxido de Carbono/química , Água do Mar/química , Transcriptoma , Adaptação Fisiológica/genética , Animais , Antozoários/fisiologia , Mudança Climática , Dados de Sequência Molecular , Oceanos e Mares , Análise de Sequência de RNA
7.
Proc Biol Sci ; 279(1734): 1716-23, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22130603

RESUMO

Global environmental changes, including ocean acidification, have been identified as a major threat to scleractinian corals. General predictions are that ocean acidification will be detrimental to reef growth and that 40 to more than 80 per cent of present-day reefs will decline during the next 50 years. Cold-water corals (CWCs) are thought to be strongly affected by changes in ocean acidification owing to their distribution in deep and/or cold waters, which naturally exhibit a CaCO(3) saturation state lower than in shallow/warm waters. Calcification was measured in three species of Mediterranean cold-water scleractinian corals (Lophelia pertusa, Madrepora oculata and Desmophyllum dianthus) on-board research vessels and soon after collection. Incubations were performed in ambient sea water. The species M. oculata was additionally incubated in sea water reduced or enriched in CO(2). At ambient conditions, calcification rates ranged between -0.01 and 0.23% d(-1). Calcification rates of M. oculata under variable partial pressure of CO(2) (pCO(2)) were the same for ambient and elevated pCO(2) (404 and 867 µatm) with 0.06 ± 0.06% d(-1), while calcification was 0.12 ± 0.06% d(-1) when pCO(2) was reduced to its pre-industrial level (285 µatm). This suggests that present-day CWC calcification in the Mediterranean Sea has already drastically declined (by 50%) as a consequence of anthropogenic-induced ocean acidification.


Assuntos
Antozoários/fisiologia , Calcificação Fisiológica/fisiologia , Água do Mar/química , Animais , Dióxido de Carbono/farmacologia , Concentração de Íons de Hidrogênio , Mar Mediterrâneo
8.
Aquat Toxicol ; 105(1-2): 166-76, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21718660

RESUMO

The anthropogenic release of carbon dioxide (CO(2)) into the atmosphere leads to an increase in the CO(2) partial pressure (pCO(2)) in the ocean, which may reach 950 µatm by the end of the 21st century. The resulting hypercapnia (high pCO(2)) and decreasing pH ("ocean acidification") are expected to have appreciable effects on water-breathing organisms, especially on their early-life stages. For organisms like squid that lay their eggs in coastal areas where the embryo and then paralarva are also exposed to metal contamination, there is a need for information on how ocean acidification may influence trace element bioaccumulation during their development. In this study, we investigated the effects of enhanced levels of pCO(2) (380, 850 and 1500 µatm corresponding to pH(T) of 8.1, 7.85 and 7.60) on the accumulation of dissolved (110m)Ag, (109)Cd, (57)Co, (203)Hg, (54)Mn and (65)Zn radiotracers in the whole egg strand and in the different compartments of the egg of Loligo vulgaris during the embryonic development and also in hatchlings during their first days of paralarval life. Retention properties of the eggshell for (110m)Ag, (203)Hg and (65)Zn were affected by the pCO(2) treatments. In the embryo, increasing seawater pCO(2) enhanced the uptake of both (110m)Ag and (65)Zn while (203)Hg showed a minimum concentration factor (CF) at the intermediate pCO(2). (65)Zn incorporation in statoliths also increased with increasing pCO(2). Conversely, uptake of (109)Cd and (54)Mn in the embryo decreased as a function of increasing pCO(2). Only the accumulation of (57)Co in embryos was not affected by increasing pCO(2). In paralarvae, the CF of (110m)Ag increased with increasing pCO(2), whereas the (57)Co CF was reduced at the highest pCO(2) and (203)Hg showed a maximal uptake rate at the intermediate pCO(2). (54)Mn and (65)Zn accumulation in paralarvae were not significantly modified by hypercapnic conditions. Our results suggest a combined effect of pH on the adsorption and protective properties of the eggshell and of hypercapnia on the metabolism of embryo and paralarvae, both causing changes to the accumulation of metals in the tissues of L. vulgaris.


Assuntos
Loligo/metabolismo , Água do Mar/química , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Dióxido de Carbono/análise , Concentração de Íons de Hidrogênio , Loligo/embriologia , Poluição da Água/efeitos adversos
10.
Eur J Surg Oncol ; 34(4): 369-76, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17560754

RESUMO

AIM: The aim of the study was to identify if radiotherapy can be safely avoided in a selected subgroup of largely screening detected small invasive breast cancer. METHODS: One hundred and eighty-eight patients with node negative invasive early breast cancer < or =1cm (< or =T1b) treated in our centre between 1990 and 2004 were retrospectively followed for local, regional and distant recurrences. Treatment involved adequate local excision by breast conserving surgery (BCS). Axillary staging was performed by a four node axillary sampling until 2000, following which sentinel lymph node sampling was employed. All sections were assessed histologically by haematoxylin and eosin stained sections. The inked margins were reported as being involved, close and clear. Radiotherapy (RT) was employed only if the resected margins were inadequate, and in those with involved axillary nodes who refused further completion axillary clearance. RESULTS: Ninety-four patients (Group A) had BCS alone and 79 patients (Group B) had both BCS and RT. There was no ipsilateral breast tumour recurrence (IBTR) in 88 patients in Group A, corresponding to an actuarial freedom from IBTR of 96%, 91% and 88.1% at 5 years, 8 years and 9 years. In Group B, there was no IBTR in 75 patients corresponding to an actuarial freedom from IBTR of 97%, 94.9% and 90.6% at 5 years, 8 years and 10 years. CONCLUSION: Our experience over 14 years has shown that it is possible to safely avoid radiotherapy in a selected subgroup of small invasive breast cancer.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/patologia , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela
11.
Eur J Surg Oncol ; 33(2): 147-52, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17081723

RESUMO

AIM: The study compared the accuracy and success rate of two techniques, methylene blue alone versus combined methylene blue and radioactive colloid in sentinel lymph node localisation in the management early breast cancer. METHODS: Three hundred and twenty-nine patients with tumours less than 2 cm on ultrasound assessment were prospectively evaluated. One hundred and seventy-three patients (Group A) underwent sentinel lymph node localisation using 1 ml of 1% methylene blue. A combined technique of both methylene blue and radioactive colloid was used in 156 patients (Group B). Application of both was subdermal and subareolar. Sentinel lymph nodes were examined by standard microscopy. Patients underwent breast conservation surgery or mastectomy and sentinel node guided four node axillary sampling+/-clearance. RESULTS: In Group A, the sentinel lymph node identification rate was 96.5%. The negative predictive value was 96.3%, with false negative of 3.7% and accuracy of 87.4%. In group B the identification rate for sentinel lymph node was 98.7%, with false negative of 4.1%, negative predictive value of 96%, and accuracy of 83.8%. CONCLUSION: Sentinel lymph node localisation using methylene blue or combined dye and radioactive tracer technique predicts the axillary lymph node status in early breast cancer with comparable success rates, accuracy and false negative rates. The combined technique facilitates quicker identification of sentinel lymph node; however the dye technique alone can be used successfully in centres without nuclear medicine facilities.


Assuntos
Neoplasias da Mama/diagnóstico , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Azul de Metileno , Biópsia de Linfonodo Sentinela/métodos , Tecnécio , Axila , Coloides , Inibidores Enzimáticos , Feminino , Seguimentos , Humanos , Metástase Linfática/diagnóstico , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Cintilografia , Reprodutibilidade dos Testes
12.
Qual Life Res ; 13(4): 761-72, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15129886

RESUMO

Quality-of-life instruments have provided important advances in measuring the quality of life of pediatric patients receiving treatment for cancer. However, the bases of these instruments have not included first-hand reports from the patients; thus, these instruments may be conceptually incomplete. We directly solicited from pediatric patients their perspectives regarding their quality of life during treatment for cancer. We conducted two pilot studies: 23 patients (aged 8-15 years) participated in the first, a cross-sectional study; and 13 patients (aged 10-18 years) participated in the second, a 2-year longitudinal study. Data were analyzed by using a semantic-content method, and the following six domains were recognized in data from both of the studies: symptoms, usual activities, social/family interactions, health status, mood, and the meaning of being ill. These domains were compared with those of seven established pediatric oncology quality-of-life instruments, none of which included all six of these domains; the domain most frequently missing was the meaning of being ill domain. Here we present a new definition of the quality of life of pediatric oncology patients that is based on six domains; this definition may ensure the completeness and sensitivity of these important instruments.


Assuntos
Neoplasias/psicologia , Psicologia do Adolescente , Psicologia da Criança , Psicometria/métodos , Qualidade de Vida/psicologia , Perfil de Impacto da Doença , Adolescente , Institutos de Câncer , Criança , Feminino , Humanos , Entrevistas como Assunto , Masculino , Neoplasias/fisiopatologia , Neoplasias/terapia , Pediatria , Projetos Piloto , Psicometria/instrumentação , Autoavaliação (Psicologia) , Inquéritos e Questionários , Tennessee
13.
Med Pediatr Oncol ; 39(1): 2-1; discussion 2, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12116072

RESUMO

BACKGROUND: Improved cure rates for childhood cancer have produced a growing population of survivors at risk for late toxicities of chemotherapy and radiation therapy. Healthy behaviors can modify these risks. We initiated a controlled prospective trial to determine if a multi-component behavioral intervention could induce change in childhood cancer survivors' health knowledge, health perceptions, and practice of health-protective behaviors. PROCEDURE: Adolescent cancer survivors attending a long-term follow-up clinic were randomized to receive standard follow-up care or standard care plus the educational intervention. Baseline measures were obtained at randomization (T(0)) and repeated 1 year (T(1)) later during the survivors' annual check-up. RESULTS: Of 272 patients enrolled and randomized, 251 are evaluable at both time points. Treatment and control groups were similar in regards to diagnosis, gender, race, and age. The change in outcome measures over the year (T(1)-T(0)) was not significantly different between the two groups as assessed by a two-sample pooled t test. However, additional exploratory analyses indicated a significant gender difference in knowledge with female survivors in the intervention group having higher scores. In addition, patients who choose certain individual health goals, such as breast/testicular self-examination, showed improved practice of the health behavior. In addition, in a very exploratory analysis, a gender difference in response to the intervention was noted, with females exhibiting a greater improvement in knowledge scores than did males. CONCLUSIONS: Although the multi-behavioral educational intervention did not induce change in health knowledge, perceptions, and behaviors of childhood cancer survivors for the treatment group as a whole, gender differences and specific health goal differences were found. These findings suggest that future interventions should be tailored to reflect gender differences and the nature of the health goal under assessment.


Assuntos
Comportamento do Adolescente/psicologia , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Estilo de Vida , Neoplasias , Educação de Pacientes como Assunto , Adaptação Psicológica , Adolescente , Intervalo Livre de Doença , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Humanos , Estudos Longitudinais , Masculino , Neoplasias/psicologia , Neoplasias/terapia , Estudos Prospectivos , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento
14.
Eur J Surg Oncol ; 28(4): 379-82, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12099645

RESUMO

AIMS: The purpose of this study was to determine the rate of local recurrence in patients with small invasive breast cancers (<1 cm) who had been treated with breast-conserving surgery either with (group 1) or without (group 2) adjuvant radiotherapy. METHODS: This is a retrospective study of 110 patients with an invasive breast cancer less than 1 cm in size, treated in our centre by breast-conserving surgery. Parameters examined included age at and mode of presentation, histopathological features, adjuvant therapy, length of follow-up and outcome in terms of local recurrence rate and death. RESULTS: In group 1 there were 59 women of median age 57 (38-80) years. The median tumour size was 9 (1-10) mm and median follow-up was 74 (15-110) months. There were no local recurrences. In group 2 the median age at presentation was 59 (48-81) years. The median tumour size was 7 (2-10) mm and median follow-up was 47 (14-93) months. There were three non-breast-cancer related deaths and three local recurrences (6%). CONCLUSIONS: A local recurrence rate of 6% at almost 4 years median follow-up suggests that it may be possible to avoid adjuvant radiotherapy in a subgroup of largely screen-detected, node-negative patients with invasive tumours less than 1 cm, in whom adequate local excision is performed. Further follow-up is required to substantiate this.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Procedimentos Desnecessários , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Estudos de Casos e Controles , Terapia Combinada , Feminino , Seguimentos , Humanos , Incidência , Mamografia , Mastectomia Segmentar , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Estadiamento de Neoplasias , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
15.
Oncol Nurs Forum ; 27(8): 1233-43, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11013904

RESUMO

PURPOSE/OBJECTIVES: To describe parental decision making about treatment options for children with cancer and determine the feasibility of a similar but larger international study. DESIGN: Exploratory. SETTINGS: A pediatric catastrophic illness research hospital in the United States and children's hospitals in Australia and Hong Kong. SAMPLE: A convenience sample of 43 parents (5 fathers and 38 mothers ages 23-59 years). METHODS: Six open-ended interview questions posed to parents during private individual interviews. Content analysis techniques were used. MAIN RESEARCH VARIABLES: Parental perceptions of (a) factors considered in the decision-making process, (b) behaviors of healthcare professionals that affected the process, and (c) satisfaction with the process. Feasibility of a larger study was estimated by considering ease of access to parents, number of refusals to participate, understanding of the interview questions, and level of interest at each setting. FINDINGS: Access to parents was possible at all sites. Refusal to participate was reported only at the U.S. site. Certain factors (e.g., getting information from the healthcare team, trusting staff) were important to all parents considering end-of-life decisions. Site-specific factors included considering alternative therapies (at the Australian site) and strengthening faith (at the U.S. site). CONCLUSIONS: A larger international study of parental decision making is feasible. Sufficient similarities in parental decision making exist across these sites to justify future efforts to identify universal decision-making factors that, in conjunction with site-specific differences, could be helpful in developing guidelines for healthcare professionals who assist parents in making treatment-related decisions for a sick child.


Assuntos
Tomada de Decisões , Neoplasias/terapia , Pais/psicologia , Relações Profissional-Família , Assistência Terminal/psicologia , Adolescente , Adulto , Austrália , Criança , Comparação Transcultural , Progressão da Doença , Estudos de Viabilidade , Feminino , Hong Kong , Humanos , Cuidados para Prolongar a Vida , Masculino , Pessoa de Meia-Idade , Enfermagem Oncológica , Ordens quanto à Conduta (Ética Médica) , Sudeste dos Estados Unidos
17.
J Nurs Adm ; 30(6): 317-24, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10868160

RESUMO

Staff nurses are expected to participate in nursing research and to use study findings. Insufficient institutional support and uncertainties about how to participate in the research process can prevent staff nurses from meeting these expectations. We describe a newly developed nursing research fellowship program designed for staff nurses who practice in an acute care setting. An overview of the entire curriculum and the outcomes of the first year of the program are described.


Assuntos
Educação Continuada em Enfermagem , Bolsas de Estudo , Pesquisa em Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/educação , Currículo , Humanos , Tennessee
18.
Proc Natl Acad Sci U S A ; 96(23): 13017-22, 1999 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-10557265

RESUMO

Two methods are commonly used to measure the community metabolism (primary production, respiration, and calcification) of shallow-water marine communities and infer air-sea CO2 fluxes: the pH-total alkalinity and pH-O2 techniques. The underlying assumptions of each technique are examined to assess the recent claim that the most widely used technique in coral reefs (pH-total alkalinity), may have provided spurious results in the past because of high rates of nitrification and release of phosphoric acid in the water column [Chisholm, J. R. M. & Barnes, D. J. (1998) Proc. Natl. Acad. Sci. USA 95, 6566-6569]. At least three lines of evidence suggest that this claim is not founded. First, the rate of nitrification required to explain the discrepancy between the two methods recently reported is not realistic as it is much higher than the rates measured in another reef system and greater than the highest rate measured in a marine environment. Second, fluxes of ammonium, nitrate, and phosphorus are not consistent with high rates of nitrification and release of phosphoric acid. Third, the consistency of the metabolic parameters obtained by using the two techniques is in good agreement in two sites recently investigated. The pH-total alkalinity technique therefore appears to be applicable in most coral reef systems. Consequently, the conclusion that most coral reef flats are sources of CO2 to the atmosphere does not need revision. Furthermore, we provide geochemical evidence that calcification in coral reefs, as well as in other calcifying ecosystems, is a long-term source of CO2 for the atmosphere.

19.
Int J Cancer Suppl ; 12: 138-42, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10679885

RESUMO

Survivors of childhood cancer are a growing and vulnerable population. Cure rates for pediatric cancers now exceed 60% and, by the year 2000, an estimated 1 of every 1,000 young adults will be a cancer survivor. Because this population is at increased risk for late medical and neoplastic complications that impact adversely on health-related quality of life, it is important to investigate methods to promote risk reduction by motivating survivors to practice health-promoting behaviors. With this background, we initiated a prospective, randomized, controlled feasibility study in which survivors attending a long-term follow-up clinic were randomized to receive standard care or standard care plus an educational intervention. Our objectives were to determine if the intervention would improve the survivors' knowledge about their cancer treatment and risks of late effects and increase their practice of health-protective behaviors. Since July 1995, 272 of 318 families (86%) approached about the study agreed to participate. Of these, 266 are evaluable for assessment of baseline knowledge and health behaviors. Demographic features, baseline knowledge, health perceptions and health behaviors did not differ among randomized groups. Assessment of the intervention's efficacy at changing health behaviors of survivors randomized to the intervention group will be available when the 1-year follow-up evaluations are completed for the study cohort. Our preliminary experience with this pilot study supports the feasibility of educational intervention research in a specialty clinic dedicated to monitoring long-term childhood cancer survivors. Int. J. Cancer Suppl. 12:138-142, 1999.


Assuntos
Promoção da Saúde , Nível de Saúde , Neoplasias/psicologia , Qualidade de Vida , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Sobreviventes
20.
Histopathology ; 33(1): 34-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9726046

RESUMO

AIM: The aetiology of idiopathic megarectum and idiopathic megacolon is unknown. We postulated that biochemical or ultrastructural abnormalities may be pathologically important, as has been observed in patients with chronic idiopathic intestinal pseudo-obstruction. METHODS AND RESULTS: Resection specimens from five patients with idiopathic megarectum or megacolon were processed for paraffin wax-embedded tissue histology (haematoxylin and eosin, Gomori trichrome and picrosirius stains, phosphatase activity and periodic acid-Schiff staining), and frozen tissue for histochemistry and electron microscopy. The antibodies used in the immunohistochemistry were to myosin light chain kinase, smooth muscle myosin, alpha and beta actins, filamin, tropomyosin, phosphorylated and dephosphorylated neurofilaments and N-CAM. Variable hypertrophy of the muscularis mucosae and externa, no atrophy, and a variable nerve density decrease in longitudinal muscle and increase in the lamina propria was seen. In one patient beta actin and myosin light chain kinase immunoreactivity was reduced. CONCLUSION: Variable changes in innervation, and an abnormal contractile protein immunoreactivity pattern in one patient, may be of pathogenic importance. These clinically homogeneous conditions are likely to be due to a range of underlying pathogenic abnormalities. A search for further specific biochemical abnormalities is justified.


Assuntos
Colo/inervação , Proteínas Contráteis/metabolismo , Megacolo/patologia , Doenças Retais/patologia , Reto/inervação , Actinas/metabolismo , Adolescente , Adulto , Colo/metabolismo , Colo/patologia , Colo/ultraestrutura , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Megacolo/metabolismo , Microscopia Eletrônica , Cadeias Leves de Miosina/metabolismo , Doenças Retais/metabolismo , Reto/metabolismo , Reto/patologia , Reto/ultraestrutura
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