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1.
Proc Biol Sci ; 287(1929): 20200562, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32546097

RESUMO

Many microbial symbionts have multiple phenotypic consequences for their animal hosts. However, the ways in which different symbiont-mediated phenotypes combine to affect fitness are not well understood. We investigated whether there are correlations between different symbiont-mediated phenotypes. We used the symbiont Spiroplasma, a striking example of a bacterial symbiont conferring diverse phenotypes on insect hosts. We took 11 strains of Spiroplasma infecting pea aphids (Acyrthosiphon pisum) and assessed their ability to provide protection against the fungal pathogen Pandora neoaphidis and the parasitoids Aphidius ervi and Praon volucre. We also assessed effects on male offspring production for five of the Spiroplasma strains. All but one of the Spiroplasma strains provided very strong protection against the parasitoid P. volucre. As previously reported, variable protection against P. neoaphidis and A. ervi was also present; male-killing was likewise a variable phenotype. We find no evidence of any correlation, positive or negative, between the different phenotypes, nor was there any evidence of an effect of symbiont phylogeny on protective phenotype. We conclude that multiple symbiont-mediated phenotypes can evolve independently from one another without trade-offs between them.


Assuntos
Afídeos/microbiologia , Spiroplasma/fisiologia , Animais , Evolução Biológica , Fenótipo , Simbiose
2.
Biochim Biophys Acta ; 1859(5): 744-56, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27032571

RESUMO

miRNAs play critical roles in heart disease. In addition to differential miRNA expression, miRNA-mediated control is also affected by variable miRNA processing or alternative 3'-end cleavage and polyadenylation (APA) of their mRNA targets. To what extent these phenomena play a role in the heart remains unclear. We sought to explore miRNA processing and mRNA APA in cardiomyocytes, and whether these change during cardiac hypertrophy. Thoracic aortic constriction (TAC) was performed to induce hypertrophy in C57BL/6J mice. RNA extracted from cardiomyocytes of sham-treated, pre-hypertrophic (2 days post-TAC), and hypertrophic (7 days post-TAC) mice was subjected to small RNA- and poly(A)-test sequencing (PAT-Seq). Differential expression analysis matched expectations; nevertheless we identified ~400 mRNAs and hundreds of noncoding RNA loci as altered with hypertrophy for the first time. Although multiple processing variants were observed for many miRNAs, there was little change in their relative proportions during hypertrophy. PAT-Seq mapped ~48,000 mRNA 3'-ends, identifying novel 3' untranslated regions (3'UTRs) for over 7000 genes. Importantly, hypertrophy was associated with marked changes in APA with a net shift from distal to more proximal mRNA 3'-ends, which is predicted to decrease overall miRNA repression strength. We independently validated several examples of 3'UTR proportion change and showed that alternative 3'UTRs associate with differences in mRNA translation. Our work suggests that APA contributes to altered gene expression with the development of cardiomyocyte hypertrophy and provides a rich resource for a systems-level understanding of miRNA-mediated regulation in physiological and pathological states of the heart.


Assuntos
Hipertrofia/genética , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Biossíntese de Proteínas/genética , Animais , Regulação da Expressão Gênica , Humanos , Camundongos , MicroRNAs/metabolismo , Miócitos Cardíacos/patologia , Poliadenilação/genética , Processamento Pós-Transcricional do RNA
3.
Mol Ecol ; 23(6): 1333-1347, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24384031

RESUMO

Many organisms have intimate associations with beneficial microbes acquired from the environment. These host-symbiont associations can be specific and stable, but they are prone to lower partner specificity and more partner-switching than vertically transmitted mutualisms. To investigate partner specificity in an environmentally acquired insect symbiosis, we used 16S rRNA gene and multilocus sequencing to survey the bacterial population in the bacteria-harbouring organ (crypts) of 49 individuals across four sympatric broad-headed bug species (Alydus calcaratus, A. conspersus, A. tomentosus and Megalotomus quinquespinosus). Similar to other insect-bacteria associations, Burkholderia spp. were the most common residents of the crypts in all four insect species (77.2% of recovered sequences). Burkholderia presence was associated with prolonged survival to adulthood in A. tomentosus, suggesting a beneficial role of these specialized associations. Burkholderia were also found in environmental reservoirs in the insects' habitat, which may facilitate acquisition by insects by increasing Burkholderia-insect encounters. Symbiont establishment could also be facilitated by resistance to insect defences; zone of inhibition assays demonstrated that Burkholderia and other bacteria isolated from crypts are resistant to insect defences that limit growth of Escherichia coli. Alternatively, the insects' defences may not efficiently kill a broad range of bacteria. Although the symbiosis is targeted to Burkholderia, the insects' crypts housed other bacteria, including non-Burkholderiaceae species. There is no significant effect of host insect species on Burkholderia distribution, suggesting a lack of strong partner specificity at finer scales. The presence of frequent partner-switching between sympatric insects and their symbionts likely prevents tight co-evolutionary dynamics.


Assuntos
Burkholderia/classificação , Heterópteros/microbiologia , Simbiose , Simpatria , Animais , Técnicas de Tipagem Bacteriana , Burkholderia/genética , Burkholderia/isolamento & purificação , DNA Bacteriano/genética , Sistema Digestório/microbiologia , Ecossistema , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo
4.
Lupus ; 16(6): 387-93, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17664228

RESUMO

The pharmacological armamentarium for the treatment of SLE is expanding and a number of novel therapies are currently under investigation. In spite of this, steroid therapy remains the cornerstone of treatment and intravenous methylprednisolone (IVMP) is still widely used in clinical practice. There is however surprisingly little evidence on which to define its precise role. The objective of this review was to consider the published evidence relating to the use of IVMP in SLE patients and also to identify open questions that still need to be answered with regard to its use. In acute flares, IVMP induces rapid suppression of acute inflammation. There is not however a strong evidence base to support the use of high doses compared to low IVMP doses or oral prednisolone. In maintenance regimes, secondary analyses suggest that IVMP may confer additional long-term renal survival over oral steroids as part of a cyclophosphamide regime. Therefore, in addition to the evaluation of novel therapies for SLE, better evidence to define the precise role of IVMP in SLE is still required.


Assuntos
Glucocorticoides/administração & dosagem , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Metilprednisolona/administração & dosagem , Corticosteroides/uso terapêutico , Relação Dose-Resposta a Droga , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Injeções Intravenosas , Metilprednisolona/efeitos adversos , Metilprednisolona/uso terapêutico , Reumatologia/tendências
5.
J Calif Dent Assoc ; 21(4): 39-42, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7686969

RESUMO

A program to produce inexpensive, custom mouth guards for high school basketball players was implemented by teams of dentists who took impressions, fabricated and then delivered the mouth guards. This community service involved three hours of donated time; the player or school was charged $7.50 for materials per mouth guard. The potential reduction of dental related injuries is immeasurable, and it is hoped that other cities will adopt a similar program.


Assuntos
Basquetebol/lesões , Traumatismos Maxilofaciais/prevenção & controle , Protetores Bucais , Adolescente , Traumatismos em Atletas/prevenção & controle , Humanos , Projetos Piloto
8.
Clin Nurse Spec ; 3(4): 178-81, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2605557

RESUMO

Clinical research involving patients in crisis may be difficult to conduct because of the psychophysiological changes in the patient and the hectic environment of the health care setting. Clinical nurse specialists have the opportunity to expand nursing knowledge and contribute to nursing practice through initiation and/or participation in research with people in crisis. This article identifies potential pitfalls in conducting research with patients in crisis and suggests strategies for selecting a research design, data collection methodologies, and obtaining consent or approval.


Assuntos
Pesquisa em Enfermagem Clínica , Intervenção em Crise , Enfermeiros Clínicos , Pesquisa em Enfermagem , Coleta de Dados/instrumentação , Humanos , Consentimento Livre e Esclarecido , Projetos de Pesquisa
9.
Med J Aust ; 147(2): 59-63, 1987 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-3037287

RESUMO

The results of a clinical and virological survey of anal warts from 85 predominantly homosexual or bisexual men is presented, together with an improved technique for the surgical treatment of these lesions. Two types of anal warts, which were classified as either "acute" or "chronic" on the basis of their appearance and clinical behaviour, were recognized commonly. However, our laboratory investigations--which consisted of the routine histopathological examination of all specimens, together with immunohistochemical testing for the common wart antigen of specimens from 30 patients and papillomavirus typing by human papillomavirus DNA probing of 27 specimens--failed to reveal any significant differences between the two classes of anal warts. By means of a dot hybridization technique with mixed human papillomavirus DNA probes for types 6 and 11 and types 16 and 18, all wart biopsy specimens that were tested were shown to contain human papillomavirus types 6/11; two specimens also contained human papillomavirus types 16/18. Southern blot hybridization studies of eight specimens revealed that five warts contained human papillomavirus type 6 only and three warts contained human papillomavirus type 11 only. Although the surgical technique that is described was successful in terms of patient acceptance and the eventual eradication of anal warts, there was a high rate of recurrence of the lesions, which necessitated repeat operations in two-thirds of the patients. The need for counselling before surgery and for regular follow-up examinations after surgery is discussed.


Assuntos
Doenças do Ânus/cirurgia , Verrugas/cirurgia , Doença Aguda , Adulto , Doenças do Ânus/microbiologia , Doenças do Ânus/patologia , Doença Crônica , Humanos , Masculino , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Recidiva , Reoperação , Verrugas/microbiologia , Verrugas/patologia
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