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1.
Community Ment Health J ; 59(6): 1035-1042, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37002486

RESUMO

Stepped care models are a mental healthcare delivery framework in which a continuum of support allows selection of a range of interventions to match a client's evolving needs and preferences. Currently in use in multiple settings worldwide, stepped care has the potential to provide a needed advance for the development of comprehensive mental health systems. However, definitions of stepped care lack consistency, resulting in differing interpretations reflected in variable implementation, ultimately limiting its replicability, utility and potential for impact. To help foster greater alignment in research and practice, we propose a set of principles for stepped care which can provide guidance on how to bridge multiple mental health services together, reduce fragmentation, and respond to the full breadth of mental health needs along a continuum of care in diverse settings. We hope that articulating these principles will foster discussion and spur mental health stakeholders to translate them into actionable standards.


Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Humanos , Saúde Mental , Transtornos Mentais/terapia
2.
MCN Am J Matern Child Nurs ; 42(5): 276-282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28639998

RESUMO

PURPOSE: To design and establish content and face validity of an evidence-informed tool that promotes parental self-reflection during the transition to parenthood. STUDY DESIGN AND METHODS: The New Parent Checklist was developed using a three-phase sequential approach: Phase 1 a scoping review and expert consultation to develop and refine a prototype tool; Phase 2 content analysis of parent focus groups; and Phase 3 assessment of utility in a cross-sectional sample of parents completing the New Parent Checklist and a questionnaire. RESULTS: The initial version of the checklist was considered by experts to contain key information. Focus group participants found it useful, appropriate, and nonjudgmental, and offered suggestions to enhance readability, utility, as well as face and content validity. In the cross-sectional survey, 83% of the participants rated the New Parent Checklist as "helpful" or "very helpful" and 90% found the New Parent Checklist "very easy" to use. Open-ended survey responses included predominantly positive feedback. Notable differences existed for some items based on respondents' first language, age, and sex. Results and feedback from all three phases informed the current version, available for download online. CLINICAL IMPLICATIONS: The New Parent Checklist is a comprehensive evidence-informed self-reflective tool with promising content and face validity. Depending on parental characteristics and infant age, certain items of the New Parent Checklist have particular utility but may also require further adaptation and testing. Local resources for information and/or support are included in the tool and could be easily adapted by other regions to incorporate their own local resources.


Assuntos
Lista de Checagem/normas , Pais/educação , Pais/psicologia , Pensamento , Adulto , Lista de Checagem/métodos , Estudos Transversais , Prática Clínica Baseada em Evidências/métodos , Prática Clínica Baseada em Evidências/normas , Feminino , Grupos Focais , Humanos , Masculino , Inquéritos e Questionários
3.
Neurobiol Dis ; 71: 245-59, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25151644

RESUMO

Vascular endothelial growth factor-A (VEGF-A) is best known as a key regulator of the formation of new blood vessels. Neutralization of VEGF-A with anti-VEGF therapy e.g. bevacizumab, can be painful, and this is hypothesized to result from a loss of VEGF-A-mediated neuroprotection. The multiple vegf-a gene products consist of two alternatively spliced families, typified by VEGF-A165a and VEGF-A165b (both contain 165 amino acids), both of which are neuroprotective. Under pathological conditions, such as in inflammation and cancer, the pro-angiogenic VEGF-A165a is upregulated and predominates over the VEGF-A165b isoform. We show here that in rats and mice VEGF-A165a and VEGF-A165b have opposing effects on pain, and that blocking the proximal splicing event - leading to the preferential expression of VEGF-A165b over VEGF165a - prevents pain in vivo. VEGF-A165a sensitizes peripheral nociceptive neurons through actions on VEGFR2 and a TRPV1-dependent mechanism, thus enhancing nociceptive signaling. VEGF-A165b blocks the effect of VEGF-A165a. After nerve injury, the endogenous balance of VEGF-A isoforms switches to greater expression of VEGF-Axxxa compared to VEGF-Axxxb, through an SRPK1-dependent pre-mRNA splicing mechanism. Pharmacological inhibition of SRPK1 after traumatic nerve injury selectively reduced VEGF-Axxxa expression and reversed associated neuropathic pain. Exogenous VEGF-A165b also ameliorated neuropathic pain. We conclude that the relative levels of alternatively spliced VEGF-A isoforms are critical for pain modulation under both normal conditions and in sensory neuropathy. Altering VEGF-Axxxa/VEGF-Axxxb balance by targeting alternative RNA splicing may be a new analgesic strategy.


Assuntos
Anticorpos/uso terapêutico , DNA Recombinante/genética , Neuralgia/metabolismo , Neuralgia/terapia , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular , Animais , Anticorpos/farmacologia , Benzofuranos , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Gânglios Espinais/citologia , Hiperalgesia/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Condução Nervosa/genética , Medição da Dor , Limiar da Dor/fisiologia , Quinolinas , RNA Mensageiro/genética , Ratos , Ratos Wistar , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo , Canais de Cátion TRPV/deficiência , Canais de Cátion TRPV/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Curr Eye Res ; 36(4): 328-35, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21309690

RESUMO

PURPOSE: Alternative splicing of the last exon (exon 8) of vascular endothelial growth factor (VEGF) pre-mRNA is a key element in the balance of pro- and anti-angiogenic VEGF isoforms in exudative age-related macular degeneration (exAMD) and proliferative diabetic retinopathy (PDR). Three splicing factors, SRp40, ASF/SF2, and SRp55 are predicted to control alternative splicing by binding to exonic splice enhancers (ESE) in VEGF exon 8. This pilot study examines whether there is an association between angiogenic eye disease and splicing factor polymorphisms, and whether there are sequence variations in the alternative splice sites of the VEGF gene. MATERIALS AND METHODS: A case:control pilot study comparing 163 individuals with angiogenic eye disease (94 exAMD and 69 PDR patients) with 95 age-matched controls. Splicing factor polymorphisms were genotyped by Restriction Fragment Length Polymorphism (RFLP) and sequencing, and the VEGF alternatively spliced region was assessed by denaturing High Performance Liquid Chromatography (dHPLC) using a transgenomic WAVE heteroduplex analyzer. RESULTS: No variations were observed in the alternatively spliced region of VEGF exon 8. ASF/SF2 polymorphisms showed no association with exAMD or PDR. For PDR, we observed a trend in SRp40 (rs6573908) where the 5136CC genotype was more frequent in controls (p = 0.0517) and a significant association of the SRp55 (rs2235611), where the 2994C allele was more common in the PDR group (p = 0.03). This remained strong, but not significant, after logistic regression for age, sex, disease type, and duration (p = 0.06). CONCLUSIONS: The lack of variation in the VEGF alternatively spliced region suggests the importance of sequence conservation in this area in maintaining the balance of pro- and anti-angiogenic VEGF isoforms. The link between PDR and the SRp55 2994 polymorphism suggests a disease-specific association between factors controlling VEGF splicing and ocular angiogenesis.


Assuntos
Processamento Alternativo/genética , Neovascularização de Coroide/genética , Polimorfismo de Nucleotídeo Único , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Retinopatia Diabética/genética , Éxons/genética , Feminino , Genótipo , Análise Heteroduplex , Humanos , Degeneração Macular/genética , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Fosfoproteínas/genética , Projetos Piloto , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Isoformas de Proteínas/genética , Proteínas de Ligação a RNA/genética , Fatores de Processamento de Serina-Arginina , Adulto Jovem
5.
Br J Cancer ; 101(7): 1183-93, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19707198

RESUMO

BACKGROUND: The key mediator of new vessel formation in cancer and other diseases is VEGF-A. VEGF-A exists as alternatively spliced isoforms - the pro-angiogenic VEGF(xxx) family generated by exon 8 proximal splicing, and a sister family, termed VEGF(xxx)b, exemplified by VEGF(165)b, generated by distal splicing of exon 8. However, it is unknown whether this anti-angiogenic property of VEGF(165)b is a general property of the VEGF(xxx)b family of isoforms. METHODS: The mRNA and protein expression of VEGF(121)b was studied in human tissue. The effect of VEGF(121)b was analysed by saturation binding to VEGF receptors, endothelial migration, apoptosis, xenograft tumour growth, pre-retinal neovascularisation and imaging of biodistribution in tumour-bearing mice with radioactive VEGF(121)b. RESULTS: The existence of VEGF(121)b was confirmed in normal human tissues. VEGF(121)b binds both VEGF receptors with similar affinity as other VEGF isoforms, but inhibits endothelial cell migration and is cytoprotective to endothelial cells through VEGFR-2 activation. Administration of VEGF(121)b normalised retinal vasculature by reducing both angiogenesis and ischaemia. VEGF(121)b reduced the growth of xenografted human colon tumours in association with reduced microvascular density, and an intravenous bolus of VEGF(121)b is taken up into colon tumour xenografts. CONCLUSION: Here we identify a second member of the family, VEGF(121)b, with similar properties to those of VEGF(165)b, and underline the importance of the six amino acids of exon 8b in the anti-angiogenic activity of the VEGF(xxx)b isoforms.


Assuntos
Neoplasias/prevenção & controle , Neovascularização Patológica/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Processamento Alternativo , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Colo/química , Neoplasias do Colo/química , Células Endoteliais/fisiologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias/patologia , Isoformas de Proteínas , Distribuição Tecidual , Fator A de Crescimento do Endotélio Vascular/farmacocinética
6.
J Obstet Gynecol Neonatal Nurs ; 38(2): 134-47, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19323710

RESUMO

OBJECTIVE: To develop a tool and evaluate its content validity and utility. The tool was designed to be used by women to assess lifestyle and psychosocial factors that could impact their pregnancies and unborn babies. It also provided resources for self-help. DESIGN: Methodological study in 4 phases. SETTING: Alberta Health Services, Calgary area and community. PARTICIPANTS: Thirty-five experts and 375 pregnant women. METHODS: Pregnant women and new mothers participated in focus groups to establish content validity; prenatal class attendees completed the self-assessment and a questionnaire, and women from the community completed a questionnaire on the instrument's utility. RESULTS: Responses from experts and participants in all 4 phases led to changes in the content, wording, and format of the tool. Survey responses indicated that it contained useful information that prompted a number of women to make positive changes during their pregnancies. CONCLUSION: The Pregnancy Wellness Guide is a simple tool that can help pregnant women assess their knowledge and health behaviors and self-refer to helpful resources. It will be widely distributed throughout the health region in the urban and rural Calgary area, and its use is anticipated to result in better health outcomes in pregnancy.


Assuntos
Estilo de Vida , Mães/educação , Guias de Prática Clínica como Assunto/normas , Complicações na Gravidez/prevenção & controle , Cuidado Pré-Natal/métodos , Autocuidado/métodos , Adulto , Alberta , Atitude Frente a Saúde , Feminino , Grupos Focais , Comportamentos Relacionados com a Saúde , Promoção da Saúde/métodos , Humanos , Bem-Estar Materno , Mães/psicologia , Papel do Profissional de Enfermagem , Relações Enfermeiro-Paciente , Gravidez , Complicações na Gravidez/psicologia
7.
Mol Vis ; 12: 626-32, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16735996

RESUMO

PURPOSE: Hypoxia driven ocular angiogenesis occurs in a range of ischemic retinopathies including proliferative diabetic retinopathy and retinopathy of prematurity. These conditions are initiated and sustained by hypoxia dependent vascular endothelial growth factor (VEGF) expression in the eye. There are two families of VEGF isoforms formed by differential splicing, the pro-angiogenic VEGF family, known to contribute to ocular neovascularization, and the anti-angiogenic VEGF family, which are downregulated in diabetic retinopathy in humans. The first member of the VEGF family to be isolated was VEGF165b. To determine whether VEGF165b could inhibit hypoxia driven angiogenesis in the eye, the oxygen induced retinopathy mouse model of ocular neovascularization was used. METHODS: 1 ng of recombinant human VEGF165b peptide was injected intraocularly upon return to normoxia after 5 days exposure to 95% oxygen, and neovascularization assessed. RESULTS: VEGF165b significantly inhibited the percentage area of retinal neovascularization from 23+/-3% to 12+/-3.3%, and significantly increased normal vascular areas from 62+/-4% to 74+/-4%. The percentage area of residual ischemic retina was not affected. CONCLUSIONS: These results show that a single injection of VEGF165b can significantly reduce preretinal neovascularization without inhibition of physiological intraretinal angiogenesis. Controlling the balance of VEGF(xxx) to VEGF(xxx) isoforms may therefore be therapeutically valuable in the treatment of proliferative eye diseases such as diabetic retinopathy and age related macular degeneration. The regulation of splicing between these two families of isoforms may provide a novel therapeutic strategy for proliferative eye disease.


Assuntos
DNA Recombinante , Variação Genética , Neovascularização Retiniana/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Animais Recém-Nascidos , Humanos , Hipóxia/complicações , Injeções , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Retina/patologia , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/patologia , Vasos Retinianos/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/administração & dosagem
8.
Diabetologia ; 48(11): 2422-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16193288

RESUMO

AIMS/HYPOTHESIS: Proliferative diabetic retinopathy results from excess blood vessel growth into the vitreous fluid of the eye. Retinal angiogenesis is regulated by expression of vascular endothelial growth factor (VEGF), and many studies have shown that VEGF is critically involved in proliferative diabetic retinopathy. VEGF is alternatively spliced to form the angiogenic (VEGF(xxx)) and potentially anti-angiogenic (VEGF(xxx)b) family of isoforms. The VEGF(xxx)b family is found in normal tissues, but down-regulated in renal and prostate cancer. Previous studies on endogenous expression of VEGF in the eye have not distinguished between the two families of isoforms. METHODS: We measured VEGF(xxx)b isoform expression in normal human eye tissue (lens, sclera, retina and iris) and vitreous fluid using enzyme-linked immunosorbent assay and Western blotting with a VEGF(xxx)b-specific antibody. RESULTS: VEGF(xxx)b protein was expressed in lens, sclera, retina, iris and vitreous fluid. Multiple isoforms were seen, including VEGF(165)b, VEGF(121)b, VEGF(145)b, VEGF(183)b and VEGF(189)b. In non-diabetic patients, 64+/-7% of the VEGF in the vitreous was VEGF(xxx)b (n=18), whereas in diabetic patients only 12.5+/-3.6% of total VEGF was VEGF(xxx)b. CONCLUSIONS/INTERPRETATION: Since VEGF(xxx)b inhibits VEGF(xxx)-induced angiogenesis in a one-to-one stoichiometric manner, these results show that in the eye of diabetic patients VEGF splicing was switched from an anti-angiogenic to a pro-angiogenic environment. This occurred through changes to the ratio of VEGF(xxx):VEGF(xxx)b. Alterations to splicing, and through that to the balance of VEGF isoforms, could therefore be a potential therapeutic strategy for diabetic retinopathy.


Assuntos
Processamento Alternativo , Retinopatia Diabética/genética , Olho/irrigação sanguínea , Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular/genética , Retinopatia Diabética/patologia , Olho/metabolismo , Humanos , Valores de Referência , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator B de Crescimento do Endotélio Vascular/genética , Fator B de Crescimento do Endotélio Vascular/metabolismo
13.
Appl Environ Microbiol ; 67(12): 5721-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11722928

RESUMO

Pathogenic strains of the soilborne fungus Periconia circinata produce peritoxins with host-selective toxicity against susceptible genotypes of sorghum. The peritoxins are low-molecular-weight, hybrid molecules consisting of a peptide and a chlorinated polyketide. Culture fluids from pathogenic, toxin-producing (Tox(+)) and nonpathogenic, non-toxin-producing (Tox(-)) strains were analyzed directly by gradient high-performance liquid chromatography (HPLC) with photodiode array detection and HPLC-mass spectrometry to detect intermediates and final products of the biosynthetic pathway. This approach allowed us to compare the metabolite profiles of Tox(+) and Tox(-) strains. Peritoxins A and B and the biologically inactive intermediates, N-3-(E-pentenyl)-glutaroyl-aspartate, circinatin, and 7-chlorocircinatin, were detected only in culture fluids of the Tox(+) strains. The latter two compounds were produced consistently by Tox(+) strains regardless of the amount of peritoxins produced under various culture conditions. In summary, none of the known peritoxin-related metabolites were detected in Tox(-) strains, which suggests that these strains may lack one or more functional genes required for peritoxin biosynthesis.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Micotoxinas/biossíntese , Precursores de Proteínas/biossíntese , Ascomicetos/metabolismo , Cromatografia Líquida de Alta Pressão , Ciclopropanos , Grão Comestível/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/biossíntese
14.
J Mot Behav ; 33(3): 306-20, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11495835

RESUMO

Three experiments were performed on reach and grasp in 9- to 10-year-old children (8 controls and 8 with developmental coordination disorder [DCD]). In normal reaching, children in the DCD group were less responsive to the accuracy demands of the task in controlling the transport component of prehension and spent less time in the deceleration phase of hand transport. When vision was removed as movement began, children in the control group spent more time decelerating and reached peak aperture earlier. Children in the DCD group did not do that, although, like the control group, they did increase grip aperture in the dark. When depth cues were reduced and only the target or only the target and hand were visible, children in the control group used target information to maintain the same grip aperture in all conditions, but DCD children behaved as if the target was not visible. Throughout the studies, the control group of 9- to 10-year-olds did not produce adult-like adaptations to reduced vision, suggesting that they had not yet attained adult-like integration of sensory input. Compared with control children, children with DCD did not exhibit increased dependence on vision but showed less recognition of accuracy demands, less adaptation to the removal of vision, and less use of minimal visual information when it was available.


Assuntos
Força da Mão , Transtornos das Habilidades Motoras/psicologia , Movimento , Desempenho Psicomotor , Visão Ocular , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil , Feminino , Mãos , Humanos , Masculino
15.
Hum Mol Genet ; 10(13): 1369-78, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11440989

RESUMO

Dominant optic atrophy (DOA) is the commonest form of inherited optic neuropathy. Although heterogeneous, a major locus has been mapped to chromosome 3q28 and the gene responsible, OPA1, was recently identified. We therefore screened a panel of 35 DOA patients for mutations in OPA1. This revealed 14 novel mutations and a further three known mutations, which together accounted for 20 of the 35 families (57%) included in this study. This more than doubles the number of OPA1 mutations reported in the literature, bringing the total to 25. These are predominantly null mutations generating truncated proteins, strongly suggesting that the mechanism underlying DOA is haploinsufficiency. The mutations are largely family-specific, although a common 4 bp deletion in exon 27 (eight different families) and missense mutations in exons 8 (two families) and 9 (two families) have been identified. Haplotype analysis of individuals with the exon 27 2708del(TTAG) mutation suggests that this is a mutation hotspot and not an ancient mutation, thus excluding a major founder effect at the OPA1 locus. The mutation screening in this study also identified a number of asymptomatic individuals with OPA1 mutations. A re-calculation of the penetrance of this disorder within two of our families indicates figures as low as 43 and 62% associated with the 2708del(TTAG) mutation. If haploinsufficiency is the mechanism underlying DOA it is unlikely that this figure will be mutation-specific, indicating that the penetrance in DOA is much lower than the 98% reported previously. To investigate whether Leber's hereditary optic neuropathy (LHON) could be caused by mutations in OPA1 we also screened a panel of 28 LHON patients who tested negatively for the three major LHON mutations. No mutations were identified in any LHON patients, indicating that DOA and LHON are genetically distinct.


Assuntos
GTP Fosfo-Hidrolases/genética , Atrofias Ópticas Hereditárias/genética , Processamento Alternativo/genética , Sequência de Aminoácidos , Códon sem Sentido , DNA/química , DNA/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Frequência do Gene , Testes Genéticos , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Mutação , Mutação de Sentido Incorreto , Atrofias Ópticas Hereditárias/diagnóstico , Linhagem , Penetrância , Polimorfismo Conformacional de Fita Simples , Deleção de Sequência , Homologia de Sequência de Aminoácidos
16.
Cytogenet Cell Genet ; 92(1-2): 97-102, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11306804

RESUMO

Dominant optic atrophy (DOA, gene OPA1) is the commonest form of inherited optic atrophy. Linkage studies have shown that a locus for this disease lies in a 1.4-cM region at chromosome 3q28-->q29 and have suggested a founder haplotype for as many as 95% of the linked families. To aid the identification of candidate genes for this disease, we have constructed a Bacterial Artificial Chromosome (BAC) contig covering approximately 3.3 Mb and encompassing the OPA1 critical region (flanking markers D3S3669 and D3S3562). This physical map corrects errors in the marker order reported in the literature, allowing the OPA1 critical region to be precisely defined. A reassessment of the founder effect in the light of the revised marker order suggests that it may not be as significant as had previously been suggested. A high-density transcript map was created by precisely mapping genes and expressed sequence tags (ESTs) from GeneMap'99, that have been loosely assigned to the region by radiation hybrid mapping. One known gene (KIAA0567 protein) and 15 ESTs were found to lie within the minimal disease region. Analysis of the sequence data already available from within the OPA1 critical region allowed the identification and mapping of a further 31 ESTs. The work presented in this study provides the basis for the characterisation of candidate genes and the ultimate identification of the gene mutated in DOA.


Assuntos
Mapeamento de Sequências Contíguas , Efeito Fundador , Genes Dominantes/genética , Haplótipos/genética , Atrofias Ópticas Hereditárias/genética , Cromossomos Artificiais Bacterianos/genética , Inglaterra , Etiquetas de Sequências Expressas , Feminino , Marcadores Genéticos/genética , Humanos , Masculino , Meiose/genética , Dados de Sequência Molecular , Mutação/genética , Linhagem , Polimorfismo Genético/genética , Sitios de Sequências Rotuladas
18.
FEMS Microbiol Lett ; 195(1): 9-15, 2001 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-11166988

RESUMO

A genetic transformation system has been developed for three Mycosphaerella pathogens of banana and plantain (Musa spp.). Mycosphaerella fijiensis and Mycosphaerella musicola, the causal agents of black and yellow Sigatoka, respectively, and Mycosphaerella eumusae, which causes Septoria leaf spot of banana, were transformed with a construct carrying a synthetic gene encoding green fluorescent protein (GFP). Most single-spored transformants that expressed GFP constitutively were mitotically stable in the absence of selection for hygromycin B resistance. Transformants of all three species were pathogenic on the susceptible banana cultivar Grand Nain, and growth in planta was comparable to wild-type strains. GFP expression by transformants allowed us to observe extensive fungal growth within leaf tissue that eventually turned necrotic, at which point the fungi grew saprophytically on the dead tissue. Leaf chlorosis and necrosis were often observed in advance of saprophytic growth of the mycelium on necrotic tissue, which supports previous reports suggesting secretion of a phytotoxin.


Assuntos
Ascomicetos/genética , Transformação Genética , Zingiberales/microbiologia , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia
19.
Exp Brain Res ; 134(1): 81-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11026729

RESUMO

Previous findings on the role of visual contact with the hand in the control of reaching and grasping have been contradictory. Some studies have shown that such contact is largely irrelevant, while more recent ones have emphasised its importance. In contrast, information arising from the surrounding environment has received relatively little attention in the study of prehensile actions. In order to identify the roles of both sources of information, we made kinematic comparisons between three conditions. In the first, reaching was performed in a dimly lit room and compared with a second condition in which reaches in the dark, but with the thumb and first finger illuminated, were made to a luminous object. This contrast allows the effects of environmental context to be identified. A comparison between the second and a third condition, in which both vision of the hand and the environment was removed, but the object was still visually available, enabled the assessment of how and when vision of the hand plays a role. Removing environmental cues had effects both early and late in the reach, while vision of the hand was only crucial in the period after peak deceleration. In addition, removal of both sources of information resulted in larger grip apertures. Differences and similarities between our findings and those of other studies are discussed, as is the ongoing debate about the relative importance of visual feedback of the hand in the control and co-ordination of prehensile actions. We conclude with suggestions for further research based on the set-up used in the present study.


Assuntos
Força da Mão/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Fenômenos Biomecânicos , Escuridão , Meio Ambiente , Retroalimentação/fisiologia , Feminino , Humanos , Iluminação , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Polegar/fisiologia
20.
Invest Ophthalmol Vis Sci ; 41(9): 2456-60, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10937553

RESUMO

PURPOSE: Rieger syndrome is an autosomal dominant condition characterized by a variable combination of anterior segment dysgenesis, dental anomalies, and umbilical hernia. To date, reports have shown mutations within the PITX2 gene associated with Rieger syndrome, iridogoniodysgenesis, and iris hypoplasia. The purposes of this study were to determine the range of expression and intrafamilial variability of PITX2 mutations in patients with anterior segment dysgenesis. METHODS: Seventy-six patients with different forms of anterior segment dysgenesis were classified clinically. DNA was obtained and screened by means of polymerase chain reaction (PCR)-single-stranded conformation polymorphism (SSCP) and heteroduplex analysis followed by direct sequencing. RESULTS: Eight of 76 patients had mutations within the PITX2 gene. Anterior segment phenotypes show wide variability and include a phenocopy of aniridia and Peters', Rieger, and Axenfeld anomalies. Mutations include premature terminations and splice-site and homeobox mutations, confirming that haploinsufficiency the likely pathogenic mechanism in the majority of cases. CONCLUSIONS: There is significant phenotypic variability in patients with PITX2 mutations, both within and between families. Developmental glaucoma is common. The umbilical and dental abnormalities are highly penetrant, define those at risk of carrying mutations in this gene, and guide mutation analysis. In addition, there is a range of other extraocular manifestations.


Assuntos
Oftalmopatias Hereditárias/genética , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Iris/anormalidades , Mutação , Proteínas Nucleares , Fatores de Transcrição/genética , Doenças da Úvea/genética , Segmento Anterior do Olho/anormalidades , Análise Mutacional de DNA , Feminino , Análise Heteroduplex , Humanos , Masculino , Fatores de Transcrição Box Pareados , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Síndrome , Proteína Homeobox PITX2
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