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1.
BMC Public Health ; 21(1): 1467, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34320975

RESUMEN

BACKGROUND: Half of mental health disorders begin before the age of 14, highlighting the importance of prevention and early-intervention in childhood. Schools have been identified globally by policymakers as a platform to support good child mental health; however, the majority of the research is focused on secondary schools, with primary schools receiving very little attention by comparison. The limited available evidence on mental health initiatives in primary schools is hindered by a lack of rigorous evaluation. This quasi-experimental cluster study aims to examine the implementation and effectiveness of a Mental Health and Wellbeing Co-ordinator role designed to build mental health capacity within primary schools. METHODS: This is a primary (ages 5-12) school-based cluster quasi-experimental study in Victoria, Australia. Before baseline data collection, 16 schools selected by the state education department will be allocated to intervention, and another 16 matched schools will continue as 'Business as Usual'. In intervention schools, a mental health and well-being coordinator will be recruited and trained, and three additional school staff will also be selected to receive components of the mental health training. Surveys will be completed by consenting staff (at 2-, 5-, 10- and 17-months post allocation) and by consenting parents/carers (at 3-, 10- and 17-months post allocation) in both intervention and business as usual schools. The primary objective is to assess the change in teacher's confidence to support student mental health and wellbeing using the School Mental Health Self-Efficacy Teacher Survey. Secondary objectives are to assess the indirect impact on systemic factors (level of support, prioritisation of child mental health), parent and teachers' mental health literacy (stigma, knowledge), care access (school engagement with community-based services), and student mental health outcomes. Implementation outcomes (feasibility, acceptability, and fidelity) and costs will also be evaluated. DISCUSSION: The current study will examine the implementation and effectiveness of having a trained Mental Health and Wellbeing Coordinator within primary schools. If the intervention increases teachers' confidence to support student mental health and wellbeing and builds the capacity of primary schools it will improve student mental health provision and inform large-scale mental health service reform. TRIAL REGISTRATION: The trial was retrospectively registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) on July 6, 2021. The registration number is ACTRN12621000873820 .


Asunto(s)
Salud Mental , Servicios de Salud Escolar , Niño , Preescolar , Humanos , Instituciones Académicas , Estudiantes , Victoria
2.
Br J Cancer ; 110(6): 1506-16, 2014 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-24569460

RESUMEN

BACKGROUND: We and others have identified the aldo-keto reductase AKR1C3 as a potential drug target in prostate cancer, breast cancer and leukaemia. As a consequence, significant effort is being invested in the development of AKR1C3-selective inhibitors. METHODS: We report the screening of an in-house drug library to identify known drugs that selectively inhibit AKR1C3 over the closely related isoforms AKR1C1, 1C2 and 1C4. This screen initially identified tetracycline as a potential AKR1C3-selective inhibitor. However, mass spectrometry and nuclear magnetic resonance studies identified that the active agent was a novel breakdown product (4-methyl(de-dimethylamine)-tetracycline (4-MDDT)). RESULTS: We demonstrate that, although 4-MDDT enters AML cells and inhibits their AKR1C3 activity, it does not recapitulate the anti-leukaemic actions of the pan-AKR1C inhibitor medroxyprogesterone acetate (MPA). Screens of the NCI diversity set and an independently curated small-molecule library identified several additional AKR1C3-selective inhibitors, none of which had the expected anti-leukaemic activity. However, a pan AKR1C, also identified in the NCI diversity set faithfully recapitulated the actions of MPA. CONCLUSIONS: In summary, we have identified a novel tetracycline-derived product that provides an excellent lead structure with proven drug-like qualities for the development of AKR1C3 inhibitors. However, our findings suggest that, at least in leukaemia, selective inhibition of AKR1C3 is insufficient to elicit an anticancer effect and that multiple AKR1C inhibition may be required.


Asunto(s)
3-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Neoplasias de la Mama/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Hidroxiprostaglandina Deshidrogenasas/antagonistas & inhibidores , Leucemia/tratamiento farmacológico , Acetato de Medroxiprogesterona/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , Miembro C3 de la Familia 1 de las Aldo-Ceto Reductasas , Neoplasias de la Mama/patología , Interacciones Farmacológicas , Femenino , Humanos , Hidroxiprostaglandina Deshidrogenasas/metabolismo , Leucemia/enzimología , Leucemia/patología , Masculino , Espectrometría de Masas , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Especificidad por Sustrato
3.
Eur J Endocrinol ; 168(2): K19-26, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23132696

RESUMEN

CONTEXT: Inactivating mutations in the enzyme hexose-6-phosphate dehydrogenase (H6PDH, encoded by H6PD) cause apparent cortisone reductase deficiency (ACRD). H6PDH generates cofactor NADPH for 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1, encoded by HSD11B1) oxo-reductase activity, converting cortisone to cortisol. Inactivating mutations in HSD11B1 cause true cortisone reductase deficiency (CRD). Both ACRD and CRD present with hypothalamic-pituitary-adrenal (HPA) axis activation and adrenal hyperandrogenism. OBJECTIVE: To describe the clinical, biochemical and molecular characteristics of two additional female children with ACRD and to illustrate the diagnostic value of urinary steroid profiling in identifying and differentiating a total of six ACRD and four CRD cases. DESIGN: Clinical, biochemical and genetic assessment of two female patients presenting during childhood. In addition, results of urinary steroid profiling in a total of ten ACRD/CRD patients were compared to identify distinguishing characteristics. RESULTS: Case 1 was compound heterozygous for R109AfsX3 and a novel P146L missense mutation in H6PD. Case 2 was compound heterozygous for novel nonsense mutations Q325X and Y446X in H6PD. Mutant expression studies confirmed loss of H6PDH activity in both cases. Urinary steroid metabolite profiling by gas chromatography/mass spectrometry suggested ACRD in both cases. In addition, we were able to establish a steroid metabolite signature differentiating ACRD and CRD, providing a basis for genetic diagnosis and future individualised management. CONCLUSIONS: Steroid profile analysis of a 24-h urine collection provides a diagnostic method for discriminating between ACRD and CRD. This will provide a useful tool in stratifying unresolved adrenal hyperandrogenism in children with premature adrenarche and adult females with polycystic ovary syndrome (PCOS).


Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/diagnóstico , Adrenarquia/genética , Deshidrogenasas de Carbohidratos/genética , Hirsutismo/congénito , Errores Congénitos del Metabolismo Esteroideo/diagnóstico , Esteroides/orina , 11-beta-Hidroxiesteroide Deshidrogenasas/deficiencia , 11-beta-Hidroxiesteroide Deshidrogenasas/genética , 11-beta-Hidroxiesteroide Deshidrogenasas/orina , Trastornos del Desarrollo Sexual 46, XX/genética , Trastornos del Desarrollo Sexual 46, XX/orina , Adolescente , Adrenarquia/orina , Adulto , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Hirsutismo/diagnóstico , Hirsutismo/genética , Hirsutismo/orina , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Persona de Mediana Edad , Sistema Hipófiso-Suprarrenal/metabolismo , Errores Congénitos del Metabolismo Esteroideo/genética , Errores Congénitos del Metabolismo Esteroideo/orina
4.
J Biol Chem ; 276(24): 21343-50, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11294832

RESUMEN

11-beta-hydroxysteroid dehydrogenase type 1 catalyzes the conversion of cortisone to hormonally active cortisol and has been implicated in the pathogenesis of a number of disorders including insulin resistance and obesity. The enzyme is a glycosylated membrane-bound protein that has proved difficult to purify in an active state. Extracted enzyme typically loses the reductase properties seen in intact cells and shows principally dehydrogenase activity. The C-terminal catalytic domain is known to contain a disulfide bond and is located within the lumen of the endoplasmic reticulum, anchored to the membrane by a single N-terminal transmembrane domain. We report here the functional expression of the catalytic domain of the human enzyme, without the transmembrane domain and the extreme N terminus, in Escherichia coli. Moderate levels of soluble active protein were obtained using an N-terminal fusion with thioredoxin and a 6xHis tag. In contrast, the inclusion of a 6xHis tag at the C terminus adversely affected protein solubility and activity. However, the highest levels of active protein were obtained using a construct expressing the untagged catalytic domain. Nonreducing electrophoresis revealed the presence of both monomeric and dimeric disulfide bonded forms; however, mutation of a nonconserved cysteine residue resulted in a recombinant protein with no intermolecular disulfide bonds but full enzymatic activity. Using the optimal combination of plasmid construct and E. coli host strain, the recombinant protein was purified to apparent homogeneity by single step affinity chromatography. The purified protein possessed both dehydrogenase and reductase activities with a K(m) of 1.4 micrometer for cortisol and 9.5 micrometer for cortisone. This study indicates that glycosylation, the N-terminal region including the transmembrane helix, and intermolecular disulfide bonds are not essential for enzyme activity and that expression in bacteria can provide active recombinant protein for future structural and functional studies.


Asunto(s)
Dominio Catalítico , Hidroxiesteroide Deshidrogenasas/química , Hidroxiesteroide Deshidrogenasas/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1 , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Western Blotting , Cromatografía en Capa Delgada , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Glicosilación , Humanos , Hidroxiesteroide Deshidrogenasas/genética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Mapeo Restrictivo
5.
Plant J ; 20(1): 119-25, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10571871

RESUMEN

The self-incompatibility response involves S-allele specific recognition between stigmatic S proteins and incompatible pollen, resulting in S-specific pollen inhibition. In Papaver rhoeas, the pollen S gene product is predicted to be a receptor that interacts with the stigmatic S protein in an S specific manner. We recently identified an S protein binding protein (SBP) in pollen that binds stigmatic S proteins, although apparently not in an S-allele-specific manner. In order to investigate the functional significance of the interaction between S proteins and SBP, we constructed mutant derivatives of the S1 protein and tested their SBP-binding activity and their biological activity. Here we present an evaluation of nine mutant derivatives of the S1 protein. Western ligand blotting was used to show that mutations to amino acid residues in predicted loops 2 and 6 of the S1 protein cause significant reductions in their SBP-binding activity. These same mutants show a concomitant reduction in their ability to inhibit incompatible pollen. This establishes a direct link between SBP binding and inhibition of incompatible pollen and implicates SBP as a pollen component playing a key role in the self-incompatibility reaction. We discuss the possible nature of the contribution of SBP in the S-specific rejection of incompatible pollen.


Asunto(s)
Mutación , Papaver/genética , Proteínas de Plantas/genética , Plantas Medicinales , Alelos , Secuencia de Aminoácidos , Sitios de Unión/genética , Secuencia Conservada , Genes de Plantas , Datos de Secuencia Molecular , Papaver/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Polen/metabolismo , Unión Proteica , Estructura Secundaria de Proteína
6.
Plant Mol Biol ; 39(5): 927-32, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10344198

RESUMEN

A detailed analysis of the currently available Arabidopsis thaliana genomic sequence has revealed the presence of a large number of open reading frames with homology to the stigmatic self-incompatibility (S) genes of Papaver rhoeas. The products of these potential genes are all predicted to be relatively small, basic, secreted proteins with similar predicted secondary structures. We have named these potential genes SPH (S-protein homologues). Their presence appears to have been largely missed by the prediction methods currently used on the genomic sequence. Equivalent homologues could not be detected in the human, microbial, Drosophila or C. elegans genomic databases, suggesting a function specific to plants. Preliminary RT-PCR analysis indicates that at least two members of the family (SPH1, SPH8) are expressed, with expression being greatest in floral tissues. The gene family may total more than 100 members, and its discovery not only illustrates the importance of the genome sequencing efforts, but also indicates the extent of information which remains hidden after the initial trawl for potential genes.


Asunto(s)
Arabidopsis/genética , Genes de Plantas , Genoma de Planta , Papaver/genética , Proteínas de Plantas , Plantas Medicinales , Polen/genética , ARN de Planta/genética , ARN de Planta/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia
7.
Plant Cell ; 10(10): 1723-32, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9761798

RESUMEN

The self-incompatibility response involves S allele-specific recognition between stigmatic S proteins and incompatible pollen. This response results in pollen inhibition. Defining the amino acid residues within the stigmatic S proteins that participate in S allele-specific inhibition of incompatible pollen is essential for the elucidation of the molecular basis of the self-incompatibility response. We have constructed mutant derivatives of the S1 protein from Papaver rhoeas by using site-directed mutagenesis and have tested their biological activity. This has enabled us to identify amino acid residues in the stigmatic S proteins of P. rhoeas that are required for S-specific inhibition of incompatible pollen. We report here the identification of several amino acid residues in the predicted hydrophilic loop 6 of the P. rhoeas stigmatic S1 protein that are involved in the inhibition of S1 pollen. Mutation of the only hypervariable amino acid, which is situated in this loop, resulted in the complete loss of ability of the S protein to inhibit S1 pollen. This clearly demonstrates that this residue plays a crucial role in pollen recognition and may also participate in defining allelic specificity. We have also established the importance of highly conserved amino acids adjacent to this hypervariable site. Our studies demonstrate that both variable and conserved amino acids in the region of the S protein corresponding to surface loop 6 are key elements that play a role in the recognition and inhibition of incompatible pollen in the pollen-pistil self-incompatibility reaction.


Asunto(s)
Papaver/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Medicinales , Polen/genética , Alelos , Secuencia de Aminoácidos , Secuencia Conservada , Cisteína/química , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Papaver/fisiología , Proteínas de Plantas/fisiología , Polen/fisiología , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Homología de Secuencia de Aminoácido
8.
Plant Mol Biol ; 30(5): 983-94, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8639756

RESUMEN

The S3 allele of the S gene has been cloned from Papaver rhoeas cv. Shirley. The sequence predicts a hydrophilic protein of 14.0 kDa, showing 55.8% identity with the previously cloned S1 allele, preceded by an 18 amino acid signal sequence. Expression of the S3 coding region in Escherichia coli produced a form of the protein, denoted S3e, which specifically inhibited S3 pollen in an in vitro bioassay. The recombinant protein was ca. 0.8 kDa larger than the native stigmatic form, indicating post-translational modifications in planta, as was previously suggested for the S1 protein. In contrast to other S proteins identified to date, S3 protein does not appear to be glycosylated. Of particular significance is the finding that despite exhibiting a high degree of sequence polymorphism, secondary structure predictions indicate that the S1 and S3 proteins may adopt a virtually identical conformation. Sequence analysis also indicates that the S1 and S3 proteins may adopt a virtually identical conformation. Sequence analysis also indicates that the P. rhoeas S alleles share some limited homology with the SLG and SRK genes from Brassica oleracea. Previously, cross-classification of different populations of P. rhoeas had revealed a number of functionally identical alleles. Probing of Western blots of stigma proteins from plants derived from a wild Spanish population which contained an allele functionally identical to the Shirley S3 allele with antiserum raised to S3e, revealed a protein (S3s) which was indistinguishable in pI and Mr from that in the Shirley population. A cDNA encoding S3s was isolated, nucleotide sequencing revealing a coding region with 99.4% homology with the Shirley-derived clone at the DNA level, and 100% homology at the amino acid level.


Asunto(s)
Alelos , Papaver/genética , Proteínas de Plantas/genética , Plantas Medicinales , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Complementario , Datos de Secuencia Molecular
9.
Proc Natl Acad Sci U S A ; 91(6): 2265-9, 1994 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8134385

RESUMEN

We present the identification, cloning, and characterization of a self-incompatibility (S) gene from Papaver rhoeas that has no significant homology to any previously reported gene sequences, including S genes from other species. This result suggests that a different self-incompatibility mechanism may be operating in this species and has important implications for the evolutionary relationships between the S genes. The S1 cDNA was cloned by using an oligonucleotide based upon N-terminal amino acid sequence data from stigmatic proteins that show complete linkage with the S1 gene. The single-copy gene has been expressed in Escherichia coli to test biological activity. Although the recombinant S1 protein (S1e) is not processed in the same way as the protein produced in the plant, it exhibits, in vitro, the specific pollen inhibitory activity expected of an S gene product; pollen carrying the S1 allele is inhibited, whereas pollen not carrying S1 is not inhibited. These results provide definitive demonstration that the product of a cloned S gene has S-specific pollen inhibitory activity.


Asunto(s)
Papaver/genética , Proteínas de Plantas/genética , Plantas Medicinales , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Evolución Biológica , Northern Blotting , Southern Blotting , Clonación Molecular , ADN , Expresión Génica , Genes de Plantas , Datos de Secuencia Molecular , Papaver/inmunología
10.
Mycopathologia ; 63(3): 177-9, 1978 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-692633

RESUMEN

Chitin assay was used to measure Absidia ramosa infection in the brain and kidneys of cortisone-treated mice. Mice dying 3 days after challenge had brain and kidney infection but normal renal function as determined by measurement of blood urea levels. Mice dying 5 or 6 days after challenge had infection in the kidneys but not the brain and were uraemic.


Asunto(s)
Encéfalo/microbiología , Quitina/análisis , Riñón/microbiología , Mucorales/crecimiento & desarrollo , Mucormicosis/microbiología , Animales , Química Encefálica , Cortisona/efectos adversos , Riñón/análisis , Masculino , Ratones , Mucormicosis/metabolismo , Urea/sangre
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