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1.
BMC Public Health ; 22(1): 1945, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261796

RESUMO

BACKGROUND: Suicide is a major issue affecting communities around the world. Community-based suicide prevention approaches can tailor activities at a local level and are recognised as a key component of national suicide prevention strategies. Despite this, research exploring their effects on completed suicides is rare. This study examined the effect of a national program of community suicide prevention networks on suicide rates in catchment areas across Australia. METHODS: Australian suicide data from the National Coronial Information System for 2001-2017 were mapped to geographic catchment areas of community suicide prevention networks and matched control areas with similar characteristics. The effect of network establishment on suicide rates was evaluated using longitudinal models including fixed effects for site type (network or control), time, season, and intervention (network establishment), with site included as a random intercept. RESULTS: Sixty suicide prevention networks were included, servicing areas with a population of 3.5 million. Networks varied in when they were established, ranging from 2007 to 2016. Across the time-period, suicide rates per 100,000 per quarter averaged 3.73 (SD = 5.35). A significant reduction in the suicide rate of 7.0% was found after establishment of networks (IRR = 0.93, 95% CI 0.87 to 0.99, p = .025). CONCLUSION: This study found evidence of an average reduction in suicide rates following the establishment of suicide prevention networks in Australian communities. These findings support the effectiveness of empowering local communities to take action to prevent suicide.


Assuntos
Prevenção do Suicídio , Humanos , Estudos Longitudinais , Austrália/epidemiologia , Redes Comunitárias , Projetos de Pesquisa
2.
Health Educ Res ; 36(1): 126-139, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33367691

RESUMO

teen Mental Health First Aid (teenMHFA) is a school-based mental health program that trains adolescents to support peers who are experiencing mental health problems or crises. The program has been evaluated for adolescents aged 15-18 years as part of a randomized controlled trial, however qualitative feedback from students on their perceptions of the program is yet to be explored. The current study describes the perspectives of students who took part in the trial. Feedback on the perceived strengths and weaknesses of the program was provided by 979 Year 10 students (M = 15.82 years, female = 43.94%, English as a first language = 72.77%) at four government funded public schools in Melbourne, Australia via online surveys. A content and thematic analysis was performed on the data using a six-step process. Students generally found the program relevant and they connected with the visual material, personal stories and interactive activities. Suggestions for improvements included encouraging active student participation in classroom discussion and providing opportunities to practice skills. School-based mental health education can benefit from input from stakeholder perspectives, particularly when designing mental health content for delivery by external trainers.


Assuntos
Educação em Saúde , Instituições Acadêmicas , Adolescente , Austrália , Feminino , Humanos , Grupo Associado , Avaliação de Programas e Projetos de Saúde , Estudantes
3.
Epidemiol Psychiatr Sci ; 29: e46, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31397261

RESUMO

AIMS: The prevalence of common mental disorders has not declined in high-income countries despite substantial increases in service provision. A possible reason for this lack of improvement is that greater willingness to disclose mental disorders might have led to increased reporting of psychiatric symptoms, thus masking reductions in prevalence. This masking hypothesis was tested using data from two trials of interventions that increased willingness to disclose and that also measured symptoms. Both interventions involved Mental Health First Aid (MHFA) training, which is known to reduce stigma, including unwillingness to disclose a mental health problem. METHODS: A cross-lagged panel analysis was carried out on data from two large Australian randomised controlled trials of MHFA training. The first trial involved 1643 high school students in Year 10 (mean age 15.87 years), who were randomised to receive either teen MHFA training or physical first aid training as the control. The second trial involved 608 Australia public servants who were randomised to receive either eLearning MHFA, blended eLearning MHFA or eLearning physical first aid as the control. In both trials, willingness to disclose a mental disorder as described in vignettes and psychiatric symptoms (K6 scale) were measured pre-training, post-training and at 12-month follow-up. RESULTS: Both trials found that MHFA training increased willingness to disclose. However, a cross-lagged panel analysis showed no effect of this change on psychiatric symptom scores. CONCLUSIONS: Greater willingness to disclose did not affect psychiatric symptom scores. Because the trials increased willingness to disclose through a randomly assigned intervention, they provide a strong causal test of the masking hypothesis. It is therefore unlikely that changes in willingness to disclose are masking reductions in prevalence in the population.


Assuntos
Transtornos Mentais/psicologia , Autorrevelação , Estigma Social , Adolescente , Adulto , Atitude Frente a Saúde , Austrália , Educação em Saúde , Humanos , Estudantes
4.
Epidemiol Psychiatr Sci ; 27(4): 346-356, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28073386

RESUMO

AIMS: The aim of the current study was to carry out a national population-based survey to assess the proportion of people disclosing mental health problems in a variety of settings. A further aim was to explore respondent characteristics associated with disclosure. METHODS: In 2014, telephone interviews were carried out with 5220 Australians aged 18+, 1381 of whom reported a mental health problem or scored highly on a symptom screening questionnaire. Questions covered disclosure of mental health problems to friends, intimate partners, other family members, supervisors or other colleagues in the workplace, teachers, lecturers or other students in the educational institution, health professionals and others in the community. Other than for intimate partners or supervisors, participants were asked whether or not they told everybody, some people or no one. Multinomial logistic regression was used to model the correlates of disclosure in each setting. RESULTS: For friends and family, respondents were more likely to disclose to some people than to everyone or to no one. In most other domains, non-disclosure was most common, including in the workplace, where non-disclosure to supervisors was more likely than disclosure. Disclosure was associated with having received treatment or with support in all settings except healthcare, while it was only associated with discrimination in two settings (healthcare and education). CONCLUSIONS: Disclosure of mental health problems does not appear to be linked to discrimination in most settings, and is typically associated with receiving support. Selective or non-disclosure may be particularly critical in workplaces, education and healthcare settings.


Assuntos
Revelação/estatística & dados numéricos , Relações Familiares/psicologia , Relações Interpessoais , Transtornos Mentais/psicologia , Saúde Mental/etnologia , Pessoas Mentalmente Doentes/psicologia , Preconceito/psicologia , Isolamento Social/psicologia , Estigma Social , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Feminino , Amigos , Inquéritos Epidemiológicos , Humanos , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Inquéritos e Questionários , Adulto Jovem
5.
Soc Psychiatry Psychiatr Epidemiol ; 51(9): 1257-64, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27048265

RESUMO

PURPOSE: To assess the associations between beliefs about the dangerousness of people with mental health problems and exposure to media reports of violence or personal experiences of fear, threat or harm. METHODS: Telephone interviews were carried out with 5220 Australians aged 18+. Respondents heard a vignette of a person with depression or early schizophrenia and were asked whether they believed him to be dangerous. Other questions covered past 12-month recall of media reports of violence and mental health problems, contact with and experiences of fear, threat or harm by people with mental health problems. Multinomial logistic regression was used to assess the associations between beliefs about dangerousness and media and these types of contact with people with mental health problems. RESULTS: For the early schizophrenia vignette, recall of media reports and having felt afraid of someone were associated with beliefs about dangerousness. For the depression vignette, media reports about violence and mental health problems or the experiences of feeling afraid or having been threatened or harmed were not strongly associated with beliefs about dangerousness. For both vignettes, knowing someone with a mental health problem and having a higher level of education were associated with less belief in dangerousness. CONCLUSIONS: Media reports may play a greater role in forming attitudes in low prevalence disorders and further efforts to reduce any adverse impact of media reporting should focus on these disorders. The study also supports the effectiveness of contact with people with mental health problems in reducing beliefs about dangerousness.


Assuntos
Atitude Frente a Saúde , Comportamento Perigoso , Transtorno Depressivo , Meios de Comunicação de Massa , Esquizofrenia , Estigma Social , Violência , Adolescente , Adulto , Austrália , Exposição à Violência , Medo , Feminino , Humanos , Modelos Logísticos , Masculino , Transtornos Mentais , Saúde Mental , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos e Questionários , Adulto Jovem
6.
Open Biol ; 6(3)2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26935951

RESUMO

Woodlice efficiently sequester copper (Cu) in 'cuprosomes' within hepatopancreatic 'S' cells. Binuclear 'B' cells in the hepatopancreas form iron (Fe) deposits; these cells apparently undergo an apocrine secretory diurnal cycle linked to nocturnal feeding. Synchrotron-based µ-focus X-ray spectroscopy undertaken on thin sections was used to characterize the ligands binding Cu and Fe in S and B cells of Oniscus asellus (Isopoda). Main findings were: (i) morphometry confirmed a diurnal B-cell apocrine cycle; (ii) X-ray fluorescence (XRF) mapping indicated that Cu was co-distributed with sulfur (mainly in S cells), and Fe was co-distributed with phosphate (mainly in B cells); (iii) XRF mapping revealed an intimate morphological relationship between the basal regions of adjacent S and B cells; (iv) molecular modelling and Fourier transform analyses indicated that Cu in the reduced Cu(+) state is mainly coordinated to thiol-rich ligands (Cu-S bond length 2.3 Å) in both cell types, while Fe in the oxidized Fe(3+) state is predominantly oxygen coordinated (estimated Fe-O bond length of approx. 2 Å), with an outer shell of Fe scatterers at approximately 3.05 Å; and (v) no significant differences occur in Cu or Fe speciation at key nodes in the apocrine cycle. Findings imply that S and B cells form integrated unit-pairs; a functional role for secretions from these cellular units in the digestion of recalcitrant dietary components is hypothesized.


Assuntos
Cobre/metabolismo , Hepatopâncreas/metabolismo , Ferro/metabolismo , Isópodes/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Sítios de Ligação , Cobre/análise , Hepatopâncreas/química , Hepatopâncreas/ultraestrutura , Ferro/análise , Isópodes/química , Isópodes/ultraestrutura , Oxirredução , Fosfatos/análise , Fosfatos/metabolismo , Espectrometria por Raios X , Enxofre/análise , Enxofre/metabolismo
7.
BJA Educ ; 16(5): 167-172, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-32288942
8.
Heredity (Edinb) ; 112(2): 132-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24045291

RESUMO

Communities of organisms inhabiting extreme terrestrial environments provide a unique opportunity to study evolutionary forces that drive population structure and genetic diversity under the combined challenges posed by multiple geogenic stressors. High abundance of an invasive pantropical earthworm (and the absence of indigenous lumbricid species) in the Furnas geothermal field (Sao Miguel Island, Azores) indicates its remarkable tolerance to high soil temperature, exceptionally high carbon dioxide and low oxygen levels, and elevated metal bioavailability, conditions which are lethal for the majority of terrestrial metazoans. Mitochondrial and nuclear markers were used to analyze the relationship between populations living inside and outside the geothermal field. Results showed that Pontoscolex corethrurus (Annelida, Oligochaeta, Glossoscolecidae) to be a genetically heterogeneous complex within the Sao Miguel landscape and is probably differentiated into cryptic species. The population exposed to the hostile soil conditions within the volcanic caldera possesses the lowest within-population mitochondrial diversity but an unexpectedly high degree of nuclear variability with several loci evidencing positive selection, parameters indicative of a genetically unique population only distantly related to conspecifics living outside the caldera. In conclusion, P. corethrurus inhabiting active volcanic soil is a discrete extremophile population that has evolved by tolerating a mixture of non-anthropogenic chemical and physical stressors.


Assuntos
Oligoquetos/genética , Solo , Animais , DNA Mitocondrial , Variação Genética , Genética Populacional , Genótipo , Dados de Sequência Molecular , Oligoquetos/classificação , Filogenia
9.
Opt Express ; 21(13): 15102-12, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23842297

RESUMO

The structures of biological molecules may soon be determined with X-ray free-electron lasers without crystallization by recording the coherent diffraction patterns of many identical copies of a molecule. Most analysis methods require a measurement of each molecule individually. However, current injection methods deliver particles to the X-ray beam stochastically and the maximum yield of single particle measurements is 37% at optimal concentration. The remaining 63% of pulses intercept no particles or multiple particles. We demonstrate that in the latter case single particle diffraction patterns can be extracted provided the particles are sufficiently separated. The technique has the potential to greatly increase the amount of data available for three-dimensional imaging of identical particles with X-ray lasers.

10.
Environ Pollut ; 173: 68-74, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23202635

RESUMO

UNLABELLED: Using synchrotron- and electron microscope-based X-ray microanalyses, the distribution and speciation of Zn and Pb were examined in situ in two earthworm species (Dendrodrilus rubidus and Lumbricus rubellus) living in heavily-polluted soils. MAIN FINDINGS: (i) Zn spectra in ingested soil and in tissues more closely resembled Zn(3)(PO(4))(2) than ZnS; (ii) Zn speciation in tissues gave a best fit for Zn to the inner shell of 4 oxygens at 1.94 Å (or nitrogens at 1.96 Å); (iii) the best fit for Pb in tissue was with a shell of oxygens at 2.18 Å and a shell of sulphurs at 2.67 Å; (iv) a component of the Zn and much of the Pb detectable in gut contents was co-distributed with S; (v) Zn and Pb display 'soft' acid affinities in soil, but 'hard' acid affinities in tissue. This is the first metal characterisation study conducted on an invertebrate quench-frozen in the field.


Assuntos
Monitoramento Ambiental/métodos , Chumbo/análise , Oligoquetos/química , Poluentes do Solo/análise , Zinco/análise , Animais , Microanálise por Sonda Eletrônica , Chumbo/química , Solo/química , Poluentes do Solo/química , Síncrotrons , Zinco/química
11.
Environ Sci Technol ; 47(2): 1073-81, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23198708

RESUMO

Understanding the relationships between accumulated metal speciation in cells and tissues of ecologically significant taxa such as earthworms will improve risk assessments. Synchrotron-based µ-focus X-ray spectroscopy was used to detect, localize, and determine ligand-speciation of Zn and Pb in thin sections of two epigeic earthworm species collected from a Pb/Zn-mine soil. The findings indicated that Zn and Pb partition predominantly as typical hard acids (i.e., strong affinities for O-donors) within liverlike chloragocytes. Moreover, Zn speciation was very similar in the chloragog and intestinal epithelia but differed subtly in the kidneylike nephridial tubules; neither Zn nor Pb was detectable in the ventral nerve cord. High resolution X-ray mapping of high pressure-frozen, ultrathin, freeze-substituted sections in a transmission electron microscope (TEM), combined with conventional TEM structural analysis, identified a new cell type packed with highly organized rough endoplasmic reticulum and containing deposits of Cd (codistributed with S); there was no evidence that these cells are major depositories of Zn or Pb. These data may be used in a systems biology approach to assist in the interpretation of metal-evoked perturbations in whole-worm transcriptome and metabolome profiles.


Assuntos
Cádmio/análise , Chumbo/análise , Oligoquetos/metabolismo , Oligoquetos/ultraestrutura , Poluentes do Solo/análise , Zinco/análise , Animais , Cádmio/metabolismo , Microanálise por Sonda Eletrônica , Monitoramento Ambiental , Chumbo/metabolismo , Solo/análise , Poluentes do Solo/metabolismo , Síncrotrons , Espectroscopia por Absorção de Raios X , Raios X , Zinco/metabolismo
12.
Psychol Med ; 42(8): 1753-62, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22166182

RESUMO

BACKGROUND: Although mental health information on the internet is often of poor quality, relatively little is known about the quality of websites, such as Wikipedia, that involve participatory information sharing. The aim of this paper was to explore the quality of user-contributed mental health-related information on Wikipedia and compare this with centrally controlled information sources. METHOD: Content on 10 mental health-related topics was extracted from 14 frequently accessed websites (including Wikipedia) providing information about depression and schizophrenia, Encyclopaedia Britannica, and a psychiatry textbook. The content was rated by experts according to the following criteria: accuracy, up-to-dateness, breadth of coverage, referencing and readability. RESULTS: Ratings varied significantly between resources according to topic. Across all topics, Wikipedia was the most highly rated in all domains except readability. CONCLUSIONS: The quality of information on depression and schizophrenia on Wikipedia is generally as good as, or better than, that provided by centrally controlled websites, Encyclopaedia Britannica and a psychiatry textbook.


Assuntos
Informação de Saúde ao Consumidor/normas , Enciclopédias como Assunto , Disseminação de Informação/métodos , Internet/normas , Transtornos Mentais , Livros de Texto como Assunto/normas , Análise de Variância , Compreensão , Humanos , Psiquiatria , Reprodutibilidade dos Testes , Ferramenta de Busca
13.
Ultramicroscopy ; 111(9-10): 1455-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21930016

RESUMO

We propose a direct, non-iterative method for the exact recovery of the complex wave in the exit-surface plane of a coherently illuminated object from a single defocused image. The method is applicable for a wide range of illumination conditions. The defocus range is subject to certain conditions, which if satisfied allow the complex exit-surface wave to be directly recovered by solving a set of linear equations. These linear equations, whose coefficients depend on the incident illumination, are obtained by analyzing the autocorrelation function of an auxiliary wave which is related to the exit-surface wave in a simple way. This autocorrelation is constructed by taking the inverse Fourier transform of the defocused image. We present an experimental proof of concept by recovering the exit-surface wave of a microfiber illuminated by a plane wave formed using a HeNe laser.


Assuntos
Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Análise de Fourier , Iluminação , Ressonância Magnética Nuclear Biomolecular
14.
Vaccine ; 29 Suppl 4: D152-4, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22486976

RESUMO

Dr. Edward Jenner's discovery and application of vaccination against smallpox was one of the most important medical advances of all time. In the modern era many millions of lives are saved each year by vaccines that work essentially on the same scientific principles established by Jenner more than 200 years ago. Jenner's country home in Berkeley, Gloucestershire, UK, where he carried out his work and where he spent most of his life, is now a museum and something of a shrine for vaccinologists. Jenner's house is also now the focal point of a new international learned society dedicated to advancing modern vaccinology. The aims of the new Jenner Society are to engage, support, and sustain the professional goals of vaccinologists, and to perpetuate the memory of Dr. Edward Jenner. Ultimately it is hoped that the Jenner Society will be recognized as one of the leading academic societies representing and promoting vaccine science around the world. We invite readers to consider joining the society (http://www.edwardjennersociety.org/).


Assuntos
Vacina Antivariólica/administração & dosagem , Vacina Antivariólica/imunologia , Varíola/história , Varíola/prevenção & controle , Vacinação/história , Vacinação/métodos , Controle de Doenças Transmissíveis/métodos , Controle de Doenças Transmissíveis/tendências , História do Século XVIII , História do Século XIX , Humanos , Museus , Sociedades , Reino Unido
15.
Environ Pollut ; 158(3): 883-90, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19818541

RESUMO

A Pb-mine site situated on acidic soil, but comprising of Ca-enriched islands around derelict buildings was used to study the spatial pattern of genetic diversity in Lumbricus rubellus. Two distinct genetic lineages ('A' and 'B'), differentiated at both the mitochondrial (mtDNA COII) and nuclear level (AFLPs) were revealed with a mean inter-lineage mtDNA sequence divergence of approximately 13%, indicative of a cryptic species complex. AFLP analysis indicates that lineage A individuals within one central 'ecological island' site are uniquely clustered, with little genetic overlap with lineage A individuals at the two peripheral sites. FTIR microspectroscopy of Pb-sequestering chloragocytes revealed different phosphate profiles in residents of adjacent acidic and calcareous islands. Bioinformatics found over-representation of Ca pathway genes in EST(Pb) libraries. Subsequent sequencing of a Ca-transport gene, SERCA, revealed mutations in the protein's cytosolic domain. We recommend the mandatory genotyping of all individuals prior to field-based ecotoxicological assays, particularly those using discriminating genomic technologies.


Assuntos
Ecossistema , Chumbo/análise , Oligoquetos/genética , Poluentes do Solo/análise , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Chumbo/metabolismo , Oligoquetos/química , Oligoquetos/classificação , Oligoquetos/metabolismo , Filogenia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Poluentes do Solo/metabolismo
16.
Environ Pollut ; 157(11): 3114-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19501438

RESUMO

Previous studies provided no unequivocal evidence demonstrating that field populations of Lumbricus rubellus Hoffmeister (1843), exhibit genetically inherited resistance to As-toxicity. In this study F1, F2 and F3 generation offspring derived from adults inhabiting As-contaminated field soil were resistant when exposed to 2000 mg kg(-1) sodium arsenate. The offspring of uncontaminated adults were not As-resistant. Cocoon viability was 80% for F1 and 82% for F2 offspring from As-contaminated adults and 59% in the F1 control population. High energy synchrotron analysis was used to determine whether ligand complexation of As differed in samples of: resistant mine-site adults, the resistant F1 and F2 offspring of the mine-site earthworms exposed to the LC(25) sodium arsenate (700 mg kg(-1)) of the F1 parental generation; and adult L. rubellus from an uncontaminated site exposed to LC(25) concentrations of sodium arsenate (50 mg kg(-1)). XANES and EXAFS indicated that As was present as a sulfur-coordinated species.


Assuntos
Arseniatos/farmacologia , Resistência a Medicamentos , Oligoquetos/efeitos dos fármacos , Oligoquetos/fisiologia , Poluentes do Solo/farmacologia , Animais , Feminino , Masculino , Mineração , Reprodução/efeitos dos fármacos
17.
Proc Biol Sci ; 276(1658): 789-97, 2009 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-19129111

RESUMO

Small incremental biological change, winnowed by natural selection over geological time scales to produce large consequences, was Darwin's singular insight that revolutionized the life sciences. His publications after 1859, including the 'earthworm book', were all written to amplify and support the evolutionary theory presented in the Origin. Darwin was unable to provide a physical basis for the inheritance of favoured traits because of the absence of genetic knowledge that much later led to the 'modern synthesis'. Mistaken though he was in advocating systemic 'gemmules' as agents of inheritance, Darwin was perceptive in seeking to underpin his core vision with concrete factors that both determine the nature of a trait in one generation and convey it to subsequent generations. This brief review evaluates the molecular genetic literature on earthworms published during the last decade, and casts light on the specific aspects of earthworm evolutionary biology that more or less engaged Darwin: (i) biogeography, (ii) species diversity, (iii) local adaptations and (iv) sensitivity. We predict that the current understanding will deepen with the announcement of a draft earthworm genome in Darwin's bicentenary year, 2009. Subsequently, the earthworm may be elevated from the status of a soil sentinel to that elusive entity, an ecologically relevant genetic model organism.


Assuntos
Regulação da Expressão Gênica/fisiologia , Genoma , Oligoquetos/genética , Proteínas/genética , Proteínas/metabolismo , Animais
18.
Environ Sci Technol ; 42(11): 4208-14, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18589989

RESUMO

Transcriptional responses of a soil-dwelling organism (the earthworm Lumbricus rubellus) to three chemicals, cadmium (Cd), fluoranthene (FA), and atrazine (AZ), were measured following chronic exposure, with the aim of identifying the nature of any shared transcriptional response. Principal component analysis indicated full or partial separation of control and exposed samples for each compound but not for the composite set of all control and exposed samples. Partial least-squares discriminant analysis allowed separation of the control and exposed samples for each chemical and also for the composite data set, suggesting a common transcriptional response to exposure. Genes identified as changing in expression level (by the least stringent test for significance) following exposure to two chemicals indicated a substantial number of common genes (> 127). The three compound overlapping gene set, however, comprised only 25 genes. We suggest that the low commonality in transcriptional response may be linked to the chronic concentrations (approximately 10% EC50) and chronic duration (28 days) used. Annotations of the three compound overlapping gene set indicated that genes from pathways most often associated with responses to environmental stress, such as heat shock, phase I and II metabolism, antioxidant defense, and cation balance, were not represented. The strongest annotation signature was for genes important in mitochondrial function and energy metabolism.


Assuntos
Atrazina/toxicidade , Cádmio/toxicidade , Fluorenos/toxicidade , Perfilação da Expressão Gênica , Herbicidas/toxicidade , Oligoquetos/efeitos dos fármacos , Animais , Oligoquetos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Poluentes do Solo/toxicidade , Transcrição Gênica/efeitos dos fármacos
19.
Clin Exp Immunol ; 147(3): 389-94, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17302886

RESUMO

Edward Jenner's discovery of vaccination must rank as one of the most important medical advances of all time and is a prominent example of the power of rational enquiry being brought to bear during the Age of Enlightenment in 18th century Europe. In the modern era many millions of lives are saved each year by vaccines that work essentially on the same principles that were established by Edward Jenner more than 200 years ago. His country home in Berkeley, Gloucestershire, is where he carried out his work and where he spent most of his life. The building is now a museum in which the life and times of Jenner are commemorated including not only the discovery of smallpox vaccination but also his other important scientific contributions to natural history and medicine. The trustees of the Edward Jenner museum are committed to promoting the museum as a real and "virtual" educational centre that is both entertaining and informative.


Assuntos
Museus , Vacinação/história , Inglaterra , História do Século XVIII , Humanos , Vacina Antivariólica/história
20.
Arch Environ Contam Toxicol ; 49(1): 45-52, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15981036

RESUMO

Morphometric analysis of transmission electron micrographs was used to compare the effects of metals on the multifunctional, metal-sequestering, chloragocyte cells of two epigeic earthworm species, Dendrodrilus rubidus and Lumbricus rubellus, inhabiting three field soils: a clean circumneutral reference soil (Dinas Powys); an acidic moderately Pb- and Zn-contaminated soil (Cwmystwyth); and a calcareous Cd-, Pb-, and Zn-contaminated soil (Draethen). The main findings were: (1) D. rubidus accumulated significantly higher tissue Cd and Pb and lower Zn concentrations than L. rubellus, especially at Draethen; (2) the volume fraction of chloragosomes was significantly lower and the volume fraction of debris vesicles significantly higher in D. rubidus from Draethen compared with L. rubellus at all sites and with the other two D. rubidus populations; (3) estimated relative toxicity factors, derived from soil metal concentrations and published EC50 data, suggested that the subcellular changes in chloragocytes, particularly in D. rubidus from Draethen, were caused mainly by Zn and Pb exposures; (4) scrutiny of the body burdens of each metal in both worm species across the three sites indicated that Cd was a major contributor to the structural changes observed in Draethen D. rubidus, and its impact was disproportionate to its soil and tissue concentrations in comparison with those of Pb and Zn. The apparent greater susceptibility of D. rubidus cells, compared with L. rubellus cells, to soil metal contaminants is discussed in light of differences in the quality and quantity of the metal body burdens accumulated by the two species. Further histopathalogic and morphometric studies on key organs and tissue of earthworms are required to provide biomarkers of exposure and to underpin linkage of biochemical-level changes and demography.


Assuntos
Metais Pesados/efeitos adversos , Metais Pesados/farmacocinética , Oligoquetos/citologia , Oligoquetos/metabolismo , Animais , Carga Corporal (Radioterapia) , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/ultraestrutura , Monitoramento Ambiental/métodos , Microscopia Eletrônica de Transmissão , Oligoquetos/efeitos dos fármacos , Especificidade da Espécie , Distribuição Tecidual
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