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1.
J Infect Dis ; 226(11): 1882-1886, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35533079

RESUMO

We estimated attack rates of severe acute respiratory syndrome coronavirus 2 Omicron (B.1.1.529) infection among people attending a nightclub and a graduation ball where >95% had at least 2 vaccine doses. Attack rates were 295 of 535 (55.1%) and 102 of 189 (54.0%), respectively (mean, 5 days postevent). At the ball, attack rates increased with time since vaccination: 12.5% among those vaccinated 1-2 months previously and 68.0% among those vaccinated ≥3 months previously; such differences were not found at the nightclub. Recent vaccination prevents Omicron infection, but is time and setting dependent, emphasizing the importance of nonpharmaceutical public health measures in addition to vaccine booster doses to maximize protection in high-risk contexts.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Incidência , COVID-19/epidemiologia , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Vacinação
2.
Lancet Reg Health West Pac ; 12: 100193, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34189493

RESUMO

BACKGROUND: COVID-19 results in persisting symptoms but there is little systematically collected data estimating recovery time following infection. METHODS: We followed 94% of all COVID-19 cases diagnosed in the Australian state of New South Wales between January and May 2020 using 3-4 weekly telephone interviews and linkage to hospitalisation and death data to determine if they had recovered from COVID-19 based on symptom resolution. Proportional hazards models with competing risks were used to estimate time to recovery adjusted for age and gender. FINDINGS: In analyses 2904 cases were followed for recovery (median follow-up time 16 days, range 1-122, IQR 11-24).There were 2572 (88.6%) who reported resolution of symptoms (262/2572 were also hospitalised), 224 (7.8%) had not recovered at last contact (28/224 were also hospitalised), 51 (1.8%) died of COVID-19, and 57 (2.0%) were hospitalised without a documented recovery date. Of those followed, 20% recovered by 10 days, 60% at 20, 80% at 30, 91% at 60, 93% at 90 and 96% at 120 days. Compared to those aged 30-49 years, those 0-29 years were more likely to recover (aHR 1.22, 95%CI 1.10-1.34) while those aged 50-69 and 70+ years were less likely to recover (aHR respectively 0.74, 95%CI 0.67-0.81 and 0.63, 95%CI 0.56-0.71). Men were faster to recover than women (aHR 1.20, 95%CI 1.11-1.29) and those with pre-existing co-morbidities took longer to recover than those without (aHR 0.90, 95%CI 0.83-0.98). INTERPRETATION: In a setting where most cases of COVID-19 were ascertained and followed, 80% of those with COVID-19 recover within a month, but about 5% will continue to experience symptoms 3 months later. FUNDING: NSW Health Emergency Response Priority Research Projects.

3.
Glia ; 69(8): 1966-1986, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33835598

RESUMO

The importance of Müller glia for retinal homeostasis suggests that they may have vulnerabilities that lead to retinal disease. Here, we studied the effect of selectively knocking down key metabolic genes in Müller glia on photoreceptor health. Immunostaining indicated that murine Müller glia expressed insulin receptor (IR), hexokinase 2 (HK2) and phosphoglycerate dehydrogenase (PHGDH) but very little pyruvate dehydrogenase E1 alpha 1 (PDH-E1α) and lactate dehydrogenase A (LDH-A). We crossed Müller glial cell-CreER (MC-CreER) mice with transgenic mice carrying a floxed IR, HK2, PDH-E1α, LDH-A, or PHGDH gene to study the effect of selectively knocking down key metabolic genes in Müller glia cells on retinal health. Selectively knocking down IR, HK2, or PHGDH led to photoreceptor degeneration and reduced electroretinographic responses. Supplementing exogenous l-serine prevented photoreceptor degeneration and improved retinal function in MC-PHGDH knockdown mice. We unexpectedly found that the levels of retinal serine and glycine were not reduced but, on the contrary, highly increased in MC-PHGDH knockdown mice. Moreover, dietary serine supplementation, while rescuing the retinal phenotypes caused by genetic deletion of PHGDH in Müller glial cells, restored retinal serine and glycine homeostasis probably through regulation of serine transport. No retinal abnormalities were observed in MC-CreER mice crossed with PDH-E1α- or LDH-A-floxed mice despite Cre expression. Our findings suggest that Müller glia do not complete glycolysis but use glucose to produce serine to support photoreceptors. Supplementation with exogenous serine is effective in preventing photoreceptor degeneration caused by PHGDH deficiency in Müller glia.


Assuntos
Células Fotorreceptoras , Degeneração Retiniana , Animais , Células Ependimogliais/metabolismo , Camundongos , Neuroglia/metabolismo , Células Fotorreceptoras/metabolismo , Retina/metabolismo , Degeneração Retiniana/metabolismo
4.
Invest Ophthalmol Vis Sci ; 59(15): 6075-6088, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30592496

RESUMO

Purpose: Subretinal fibroneovascularization is one of the most common causes of vision loss in neovascular AMD (nAMD). Anti-VEGF therapy effectively inhibits vascular leak and neovascularization but has little effect on fibrosis. This study aimed to identify a combination therapy to concurrently inhibit subretinal neovascularization and prevent fibrosis. Methods: We generated transgenic mice in which induced disruption of Müller cells leads to subretinal neovascularization, which is reliably accompanied by subretinal fibrosis. We conducted Western blots and immunohistochemistry to study changes in transforming growth factor-ß (TGFß) signaling including endoglin, a coreceptor essential for TGFß signaling, and then tested the effects of monthly intravitreal injection of anti-VEGF-A and anti-endoglin, either alone or in combination, on the development of subretinal fibroneovascularization in our transgenic mice. Results: Müller cell disruption increased expression of TGFß1, TGFß type 1 receptor, and phosphorylated-Smad3. Endoglin was strongly expressed in subretinal fibroneovascular tissue. Fluorescein angiography and measurements of retinal vascular permeability indicated that intravitreal anti-VEGF-A in combination with anti-endoglin treatment more efficiently inhibited vascular leak compared with either monotherapy. Immunostaining of retinal wholemounts with antibodies against glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1 indicated that the combination therapy also effectively prevented subretinal fibrosis and inhibited microglial activation. Luminex cytokine assays indicated that intravitreal anti-VEGF-A and anti-endoglin treatment, either alone or in combination, reduced the production of IL33 and macrophage inflammatory protein-3α. Conclusions: Our findings offer a potentially novel combination approach to concurrently managing subretinal neovascularization and fibrosis in nAMD.


Assuntos
Anticorpos Monoclonais/farmacologia , Endoglina/imunologia , Células Ependimogliais/patologia , Retina/patologia , Neovascularização Retiniana/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/imunologia , Animais , Western Blotting , Proteínas de Ligação ao Cálcio/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Combinação de Medicamentos , Células Ependimogliais/metabolismo , Fibrose/metabolismo , Fibrose/prevenção & controle , Angiofluoresceinografia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Injeções Intravítreas , Camundongos , Camundongos Transgênicos , Proteínas dos Microfilamentos/metabolismo , Fosforilação , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Retina/metabolismo , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/metabolismo , Vasos Retinianos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
BMJ Open ; 8(2): e020219, 2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29453303

RESUMO

OBJECTIVE: The positive deviance approach seeks to identify and learn from exceptional performers. Although a framework exists to apply positive deviance within healthcare organisations, there is limited guidance to support its implementation. The approach has also rarely explored exceptional performance on broad outcomes, been implemented at ward level, or applied within the UK. This study develops and critically appraises a pragmatic method for identifying positively deviant wards using a routinely collected, broad measure of patient safety. DESIGN: A two-phased observational study was conducted. During phase 1, cross-sectional and temporal analyses of Safety Thermometer data were conducted to identify a discrete group of positively deviant wards that consistently demonstrated exceptional levels of safety. A group of matched comparison wards with above average performances were also identified. During phase 2, multidisciplinary staff and patients on the positively deviant and comparison wards completed surveys to explore whether their perceptions of safety supported the identification of positively deviant wards. SETTING: 34 elderly medical wards within a northern region of England, UK. PARTICIPANTS: Multidisciplinary staff (n=161) and patients (n=188) clustered within nine positively deviant and comparison wards. RESULTS: Phase 1: A combination of analyses identified five positively deviant wards that performed best in the region, outperformed their organisation and performed consistently well over 12 months. Five above average matched comparator wards were also identified. Phase 2: Staff and patient perceptions of safety generally supported the identification of positively deviant wards using Safety Thermometer data, although patient perceptions of safety were less concordant with the routinely collected data. CONCLUSIONS: This study tentatively supports a pragmatic method of using routinely collected data to identify positively deviant elderly medical wards; however, it also highlights the various challenges that are faced when conducting the first stage of the positive deviance approach. TRIAL REGISTRATION NUMBER: UK Clinical Research Network Portfolio (reference-18050).


Assuntos
Unidades Hospitalares/normas , Segurança do Paciente/estatística & dados numéricos , Segurança do Paciente/normas , Gestão da Segurança/métodos , Idoso , Estudos Transversais , Inglaterra , Feminino , Humanos , Masculino , Corpo Clínico Hospitalar , Inquéritos e Questionários , Termômetros/estatística & dados numéricos
6.
Artigo em Inglês | MEDLINE | ID: mdl-28603643

RESUMO

BACKGROUND: Young women diagnosed with breast cancer may be confronted by many difficult decisions, especially around fertility preservation prior to commencing cancer treatment. The information to be conveyed is complex, and it may be difficult to weigh up the risks and benefits of the different fertility preservation options available. This complexity is compounded by the widespread low levels of literacy and health literacy in Australia, which may result in greater difficulties in understanding available health information and in decision-making. METHODS/DESIGN: A working group of experts have developed a fertility-related online decision aid for a low health literacy population, guided by health literacy principles. The decision aid will be pilot tested with 30 women diagnosed with early breast cancer between 5 years and 6 months previously. To be eligible, at the time of diagnosis, women must be between 18 and 40 years (inclusive), pre-menopausal, have no history of metastatic disease, have not completed their families, be able to give informed consent and have low health literacy. Participants will be asked to reflect back to the time in which they were diagnosed. Participants will complete a questionnaire before and after reviewing the decision aid to determine the feasibility, use and acceptability of the decision aid. The decision aid will be modified accordingly. Participants may also choose to review a previously developed (high literacy) decision aid and provide feedback in comparison to the low health literacy decision aid. DISCUSSION: This project represents the first study to develop an online fertility decision aid developed from low health literacy models in the context of breast cancer. It is anticipated that the low health literacy decision aid will be useful and acceptable to young women with low health literacy who have been diagnosed with breast cancer and that it will be preferred over the high literacy decision aid. TRIAL REGISTRATION: ACTRN12615001364561p.

7.
Org Biomol Chem ; 15(14): 3046-3059, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28318003

RESUMO

Leveraging our quinolone-1-(2H)-one based Hedgehog signalling pathway (HSP) inhibitors we have developed two new classes of HSP inhibitors based on: l-tryptophan and benzo[1,3]dioxol-5-ylmethyl-[2-(1H-indol-3-yl)-ethyl]-amine. Synthesis of focused compound libraries identified six l-tryptophan based inhibitors, and two stimulators, of Gli at 10 µM compound concentration. 2,4-Dichloro-13 and indole 16 suppressed mRNA expression of Ptch1 in Shh LIGHT2 cells, with 13 suppressing and 16 stimulating Gli2 mRNA expression. Focused library development of the benzo[1,3]dioxol-5-ylmethyl-[2-(1H-indol-3-yl)-ethyl]-amine scaffold afforded two sub-micro molar potent inhibitors of Gli expression with 5-methoxy-1H-indole-2-carboxylic acid benzo[1,3]dioxol-5-ylmethyl-[2-(1H-indol-3-yl)-ethyl]-amide 29 and 5-chloro-1H-indole-2-carboxylic acid benzo[1,3]dioxol-5-ylmethyl-[2-(1H-indol-3-yl)-ethyl]-amide 30 returning IC50 values of 0.5 and 0.24 µM, respectively. Neither 29 nor 30 acted directly on Smo with our data supporting inhibition of the HSP downstream of Smo.


Assuntos
Proteínas Hedgehog/metabolismo , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Linhagem Celular
8.
Sci Rep ; 6: 35084, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27725702

RESUMO

The dynamin family of proteins play important regulatory roles in membrane remodelling and endocytosis, especially within brain and neuronal tissues. In the context of reproduction, dynamin 1 (DNM1) and dynamin 2 (DNM2) have recently been shown to act as key mediators of sperm acrosome formation and function. However, little is known about the roles that these proteins play in the developing testicular germ cells. In this study, we employed a DNM2 germ cell-specific knockout model to investigate the role of DNM2 in spermatogenesis. We demonstrate that ablation of DNM2 in early spermatogenesis results in germ cell arrest during prophase I of meiosis, subsequent loss of all post-meiotic germ cells and concomitant sterility. These effects become exacerbated with age, and ultimately result in the demise of the spermatogonial stem cells and a Sertoli cell only phenotype. We also demonstrate that DNM2 activity may be temporally regulated by phosphorylation of DNM2 via the kinase CDK1 in spermatogonia, and dephosphorylation by phosphatase PPP3CA during meiotic and post-meiotic spermatogenesis.


Assuntos
Dinamina II/metabolismo , Espermatogênese , Testículo/fisiologia , Animais , Proteína Quinase CDC2/metabolismo , Calcineurina/metabolismo , Diferenciação Celular , Técnicas de Inativação de Genes , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Testículo/citologia
9.
Org Biomol Chem ; 14(26): 6304-15, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27272335

RESUMO

A series of quinolone-2-(1H)-ones derived from the Ugi-Knoevenagel three- and four-component reaction were prepared exhibiting low micromolar cytotoxicity against a panel of eight human cancer cell lines known to possess the Hedgehog Signalling Pathway (HSP) components, as well as the seminoma TCAM-2 cell line. A focused SAR study was conducted and revealed core characteristics of the quinolone-2-(1H)-ones required for cytotoxicity. These requirements included a C3-tethered indole moiety, an indole C5-methyl moiety, an aliphatic tail or an ester, as well as an additional aromatic moiety. Further investigation in the SAG-activated Shh-LIGHT2 cell line with the most active analogues: 2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(1-methyl-1H-indol-3-yl)-N-(pentan-2-yl)acetamide (5), 2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(5-methyl-1H-indol-3-yl)-N-(pentan-2-yl)acetamide (23) and ethyl (2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(5-methyl-1H-indol-3-yl)acetyl)glycinate (24) demonstrated a down regulation of the HSP via a reduction in Gli expression, and in the mRNA levels of Ptch1 and Gli2. Analogues 5, 23 and 24 returned in cell inhibition values of 11.6, 2.9 and 3.1 µM, respectively, making this new HSP-inhibitor pharmacophore amongst the most potent non-Smo targeted inhibitors thus far reported.


Assuntos
Antineoplásicos/farmacologia , Proteínas Hedgehog/antagonistas & inibidores , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas Hedgehog/metabolismo , Humanos , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/química , Relação Estrutura-Atividade
10.
BMC Res Notes ; 9: 90, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26867928

RESUMO

Health services researchers face two obstacles to sample size calculation: inaccessible, highly specialised or overly technical literature, and difficulty securing methodologists during the planning stages of research. The purpose of this article is to provide pragmatic sample size calculation guidance for researchers who are designing a health services study. We aimed to create a simplified and generalizable process for sample size calculation, by (1) summarising key factors and considerations in determining a sample size, (2) developing practical steps for researchers-illustrated by a case study and, (3) providing a list of resources to steer researchers to the next stage of their calculations. Health services researchers can use this guidance to improve their understanding of sample size calculation, and implement these steps in their research practice.


Assuntos
Pesquisa sobre Serviços de Saúde , Tamanho da Amostra , Humanos , Modelos Estatísticos
11.
BMJ Open ; 5(12): e010349, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26644128

RESUMO

INTRODUCTION: Despite the growing body of research on quality and safety in healthcare, there is little evidence of the association between the way hospitals are organised for quality and patient factors, limiting our understanding of how to effect large-scale change. The 'Deepening our Understanding of Quality in Australia' (DUQuA) study aims to measure and examine relationships between (1) organisation and department-level quality management systems (QMS), clinician leadership and culture, and (2) clinical treatment processes, clinical outcomes and patient-reported perceptions of care within Australian hospitals. METHODS AND ANALYSIS: The DUQuA project is a national, multilevel, cross-sectional study with data collection at organisation (hospital), department, professional and patient levels. Sample size calculations indicate a minimum of 43 hospitals are required to adequately power the study. To allow for rejection and attrition, 70 hospitals across all Australian jurisdictions that meet the inclusion criteria will be invited to participate. Participants will consist of hospital quality management professionals; clinicians; and patients with stroke, acute myocardial infarction and hip fracture. Organisation and department-level QMS, clinician leadership and culture, patient perceptions of safety, clinical treatment processes, and patient outcomes will be assessed using validated, evidence-based or consensus-based measurement tools. Data analysis will consist of simple correlations, linear and logistic regression and multilevel modelling. Multilevel modelling methods will enable identification of the amount of variation in outcomes attributed to the hospital and department levels, and the factors contributing to this variation. ETHICS AND DISSEMINATION: Ethical approval has been obtained. Results will be disseminated to individual hospitals in de-identified national and international benchmarking reports with data-driven recommendations. This ground-breaking national study has the potential to influence decision-making on the implementation of quality and safety systems and processes in Australian and international hospitals.


Assuntos
Hospitais/normas , Avaliação de Processos e Resultados em Cuidados de Saúde/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Austrália , Protocolos Clínicos , Estudos Transversais , Humanos , Modelos Lineares , Modelos Logísticos , Análise Multinível , Cultura Organizacional , Avaliação de Processos e Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados da Assistência ao Paciente , Garantia da Qualidade dos Cuidados de Saúde/métodos
12.
Biomolecules ; 5(3): 1228-44, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26131972

RESUMO

Characterizing the mechanisms underlying follicle development in the ovary is crucial to understanding female fertility and is an area of increasing research interest. The RNA binding protein Musashi is essential for post-transcriptional regulation of oocyte maturation in Xenopus and is expressed during ovarian development in Drosophila. In mammals Musashi is important for spermatogenesis and male fertility, but its role in the ovary has yet to be characterized. In this study we determined the expression of mammalian Musashi proteins MSI1 and MSI2 during mouse folliculogenesis, and through the use of a MSI2-specific knockout mouse model we identified that MSI2 is essential for normal follicle development. Time-course characterization of MSI1 and MSI2 revealed distinct differences in steady-state mRNA levels and protein expression/localization at important developmental time-points during folliculogenesis. Using a gene-trap mouse model that inactivates Msi2, we observed a significant decrease in ovarian mass, and change in follicle-stage composition due to developmental blocking of antral stage follicles and pre-antral follicle loss through atresia. We also confirmed that hormonally stimulated Msi2-deficient mice produce significantly fewer MII oocytes (60.9% less than controls, p < 0.05). Furthermore, the majority of these oocytes are of poor viability (62.2% non-viable/apoptotic, p < 0.05), which causes a reduction in female fertility evidenced by decreased litter size in Msi2-deficient animals (33.1% reduction to controls, p < 0.05). Our findings indicate that MSI1 and MSI2 display distinct expression profiles during mammalian folliculogenesis and that MSI2 is required for pre-antral follicle development.


Assuntos
Técnicas de Inativação de Genes , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Folículo Ovariano/crescimento & desenvolvimento , Proteínas de Ligação a RNA/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Folículo Ovariano/metabolismo , Proteínas de Ligação a RNA/metabolismo
13.
Biol Reprod ; 90(5): 92, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24671879

RESUMO

Spermatogenesis is a complex developmental process whereby diploid spermatogenic stem cells become haploid and undergo a series of morphological changes to produce physically mature spermatozoa. Crucial to this process are a number of RNA-binding proteins, responsible for the posttranscriptional control of essential mRNAs and particularly pertinent to the two periods of inactive transcription that occur in spermatogenesis. One such group of RNA-binding proteins is the Musashi family, specifically Musashi-1 (MSI1) and Musashi-2 (MSI2), which act as key translational regulators in various stem cell populations and have been linked with the induction of tumorigenesis. In the present study, we examined the differential expression of mammalian MSI1 and MSI2 during germ cell development in the mouse testis. MSI1 was found to be predominately localized in mitotic gonocytes and spermatogonia, whereas MSI2 was detected in meiotic spermatocytes and differentiating spermatids. Extensive examination of the function of Musashi in spermatogenesis was achieved through the use of two transgenic mouse models with germ cell-specific overexpression of full-length isoforms of Msi1 or Msi2. These models demonstrated that aberrant expression of either Msi1 or Msi2 has deleterious effects on normal spermatogenesis, with Msi2 overexpression resulting in male sterility. Studies undertaken on human testicular seminoma tumors provide further insights into the relevance of MSI1 and MSI2 overexpression as diagnostic markers to human stem cell cancers. Overall this study provides further evidence for the unique functions that RNA-binding protein isoforms occupy within spermatogenesis, and introduces the potential manipulation of the Musashi family proteins to elucidate the mechanisms of posttranscriptional gene expression during germ cell development.


Assuntos
Proteínas de Ligação a RNA/fisiologia , Espermatócitos/fisiologia , Espermatogênese/fisiologia , Espermatogônias/fisiologia , Testículo/fisiologia , Animais , Western Blotting , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Imuno-Histoquímica , Masculino , Meiose/genética , Meiose/fisiologia , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Isoformas de Proteínas , RNA/química , RNA/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espermatócitos/ultraestrutura , Espermatogônias/ultraestrutura , Estatísticas não Paramétricas , Testículo/citologia , Testículo/metabolismo
14.
Development ; 141(6): 1354-65, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24553289

RESUMO

Fizzy-related 1 (FZR1) is an activator of the Anaphase promoting complex/cyclosome (APC/C) and an important regulator of the mitotic cell division cycle. Using a germ-cell-specific conditional knockout model we examined its role in entry into meiosis and early meiotic events in both sexes. Loss of APC/C(FZR1) activity in the male germline led to both a mitotic and a meiotic testicular defect resulting in infertility due to the absence of mature spermatozoa. Spermatogonia in the prepubertal testes of such mice had abnormal proliferation and delayed entry into meiosis. Although early recombination events were initiated, male germ cells failed to progress beyond zygotene and underwent apoptosis. Loss of APC/C(FZR1) activity was associated with raised cyclin B1 levels, suggesting that CDK1 may trigger apoptosis. By contrast, female FZR1Δ mice were subfertile, with premature onset of ovarian failure by 5 months of age. Germ cell loss occurred embryonically in the ovary, around the time of the zygotene-pachytene transition, similar to that observed in males. In addition, the transition of primordial follicles into the growing follicle pool in the neonatal ovary was abnormal, such that the primordial follicles were prematurely depleted. We conclude that APC/C(FZR1) is an essential regulator of spermatogonial proliferation and early meiotic prophase I in both male and female germ cells and is therefore important in establishing the reproductive health of adult male and female mammals.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Proteínas Cdh1/metabolismo , Animais , Proteínas Cdh1/deficiência , Proteínas Cdh1/genética , Ciclina B1/metabolismo , Quebras de DNA de Cadeia Dupla , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Infertilidade Feminina/patologia , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Prófase Meiótica I/genética , Prófase Meiótica I/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Oogênese/genética , Oogênese/fisiologia , Ovário/metabolismo , Ovário/patologia , Gravidez , Caracteres Sexuais , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatogônias/citologia , Espermatogônias/metabolismo , Testículo/metabolismo , Testículo/patologia
15.
J Phys Act Health ; 11(7): 1420-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24368328

RESUMO

BACKGROUND: Physical activity interventions targeting older adults are optimized if barriers and enablers are better understood. This study identified barriers and enablers of physical activity and examined whether these were associated with meeting physical activity recommendations. METHODS: 2225 adults aged 65 years and above who perceived themselves to be insufficiently active but would like to be more physically active self-reported their barriers and enablers to physical activity in the 2009 New South Wales Falls Prevention Survey. Binary logistic regression analyses examined associations between barriers and enablers and meeting the physical activity recommendation. RESULTS: After adjusting for gender, age, BMI, and education, people who listed ill health (52%; OR = 0.56, 95% CI 0.45 to 0.70) as a barrier or who listed people to exercise with (4%; OR = 0.49, 95% CI 0.27 to 0.88) as an enabler had significantly lower odds of meeting recommendations. Those citing too expensive (3%) as a barrier (OR = 2.07, 95% CI 1.11 to 3.87) or who listed nothing will help (29%; OR = 1.40, 95% CI 1.10 to 1.77) and making time to be active (9%; OR = 1.78, 95% CI 1.23 to 2.58) as enablers had significantly higher odds of meeting physical activity recommendations. CONCLUSIONS: These findings give insights into older adults' perceptions of factors that influence their physical activity, which could assist physical activity program planning in this population.


Assuntos
Exercício Físico/psicologia , Promoção da Saúde , Esforço Físico , Apoio Social , Adulto , Idoso , Austrália , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato
16.
Front Neurosci ; 7: 100, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23781169

RESUMO

Neonatal immune challenge by administration of lipopolysaccharide (LPS) produces enduring alterations in the development and activity of neuroendocrine, immune and other physiological systems. We have recently reported that neonatal exposure to an immune challenge by administration of LPS results in altered reproductive development in the female Wistar rat. Specifically, LPS-treated animals exhibited diminished ovarian reserve and altered reproductive lifespan. In the current study, we examined the cellular mechanisms that lead to the previously documented impaired ovulation and reduced follicular pool. Rats were administered intraperitoneally either 0.05 mg/kg of LPS (Salmonella Enteritidis) or an equivalent volume of non-pyrogenic saline on postnatal days (PNDs) 3 and 5, and ovaries were obtained on PND 7. Microarray analysis revealed a significant upregulation in transcript expression (2-fold change; p < 0.05) for a substantial number of genes in the ovaries of LPS-treated animals, implicated in immune cell signaling, inflammatory responses, reproductive system development and disease. Several canonical pathways involved in immune recognition were affected by LPS treatment, such as nuclear factor-κB (NF-κB) activation and LPS-stimulated mitogen-activated protein kinase (MAPK) signaling. Quantitative Real-time PCR analysis supported the microarray results. Protein expression analysis of several components of the MAPK signaling pathway revealed a significant upregulation in the expression of Toll-like receptor 4 (TLR4) in the neonatal ovary of LPS-treated animals. These results indicate that neonatal immune challenge by administration of LPS has a direct effect on the ovary during the sensitive period of follicular formation. Given the pivotal role of inflammatory processes in the regulation of reproductive health, our findings suggest that early life immune activation via TLR signaling may have significant implications for the programming of ovarian development and fertility.

17.
Prev Med ; 55(6): 613-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23064022

RESUMO

OBJECTIVE: To examine older people's participation in fall prevention exercise/physical activities. METHODS: Participants comprised 5,681 randomly selected older people (≥ 65 years) who took part in the 2009 New South Wales (Australia) Fall Prevention telephone survey (61% response-rate). The instrument consisted of 11 prompted activities including two separate questions on participation in strength and balance training. Tai chi, dance, team sports, golf, bowls and specific balance training were classified as balance-challenging activities. Correlates of low participation were examined using multivariable logistic regression. RESULTS: One in eight older people (12.0%, 95% CI: 11.0-13.0) participated in strength training, 6.0% (95% CI: 5.2-6.7) participated in balance training and 21.8% (95% CI: 20.5-23.0) participated in balance-challenging activities. Adherence to public health recommendations (≥ 2 days/week) for strength or balance-challenging activities was reported by 21.0% (95% CI: 9.8-22.2) with 5.3% adhering to both forms. Engagements in strength or in balance-challenging activities were lower among those who had low education (

Assuntos
Acidentes por Quedas/prevenção & controle , Técnicas de Exercício e de Movimento , Cooperação do Paciente , Idoso , Idoso de 80 Anos ou mais , Intervalos de Confiança , Feminino , Humanos , Modelos Logísticos , Masculino , New South Wales , Equilíbrio Postural/fisiologia , Pesquisa Qualitativa , Treinamento Resistido/métodos
18.
J Paediatr Child Health ; 47(10): 717-22, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21449901

RESUMO

AIM: The fetal or post-natal diagnosis of major congenital cardiac abnormality has important medical and psychological consequences. METHODS: We reviewed infants who underwent cardiac surgery in the first year of life at the Heart Centre for Children, The Children's Hospital at Westmead during 2009. The aims of this study were to: (i) examine the key features of cardiac diagnosis and clinical outcome, and (ii) consider how these data can inform priorities for the delivery of clinical services. RESULTS: Over the 12-month study period, a first cardiac surgical procedure was performed on 195 infants, with 85 infants (44%) diagnosed in the antenatal period. Of the total sample, a subset of 90 babies (46%) underwent their first procedure in the neonatal period, with 62% having had a fetal diagnosis. Major intracardiac lesions including truncus arteriosus (100%), single ventricular lesions (83%), pulmonary atresia with ventricular septal defect (78%) and transposition of the great arteries (53%) were diagnosed prior to birth. Improved haemodynamic stability at initial presentation was found in those with a fetal diagnosis. The overall mortality rate for all patients was 6.1% at 12 months, with a higher mortality in infants with single ventricle. CONCLUSIONS: The contemporary paradigm of care for infants with major congenital heart disease requires a multidisciplinary approach to care, with improvements in clinician-clinician and clinician-family communication, and psychological support and education for families. Changes in the allocation of resources are required to meet this model of best practice.


Assuntos
Família/psicologia , Cardiopatias Congênitas/diagnóstico , Cuidado Pós-Natal , Diagnóstico Pré-Natal , Feminino , Idade Gestacional , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Humanos , Mortalidade Infantil , Recém-Nascido , Auditoria Médica , New South Wales , Avaliação de Resultados em Cuidados de Saúde
19.
Heart Lung Circ ; 20(7): 460-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21514216

RESUMO

BACKGROUND: We sought to compare overall mortality with neonatal outcomes over a five year period to define risk factors for mortality and service development priorities. METHODS: A retrospective cohort study of surgical outcomes following repair or palliation of structural congenital heart defects January 2005-2010. We defined mortality according to contemporary international guidelines and classified surgical procedures using the Risk Adjustment in Congenital Heart Surgery (RACHS-1) score. The effect of age and weight at operation on mortality and annual variation in case-complexity and surgeon case-mix were assessed. Subgroup analysis was performed in patients who were ≤30 days at operation (neonates). RESULTS: Overall mortality within 30 days of operation or prior to hospital discharge was 1.3 and 1.9%, respectively. Mortality was higher in neonates (6.8%) and low birth weight infants (≤2.5kg) (12.1%). Mortality was similar in bypass versus non-bypass procedures (odds ratio 0.74, p=0.425). Annual mortality rates were consistent despite a marked increase in case-complexity. Neonates overall required longer periods of intensive care support and were more likely to suffer serious complications compared to older children. Age, weight and RACHS-1 score were independent risk factors for mortality on multivariate analysis. In neonates undergoing bypass procedures, only RACHS-1 score was a significant risk factor. CONCLUSIONS: This study provides an accurate and contemporary audit of mortality risk associated with congenital heart surgery. Outcomes compare favourably to international benchmarks but highlight the risks of morbidity and mortality associated with neonatal cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
20.
Toxicol Sci ; 118(2): 653-66, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20829426

RESUMO

Mammalian females are born with a finite number of nonrenewing primordial follicles, the majority of which remain in a quiescent state for many years. Because of their nonrenewing nature, these "resting" oocytes are particularly vulnerable to xenobiotic insult, resulting in premature ovarian senescence and the formation of dysfunctional oocytes. In this study, we characterized the mechanisms of ovotoxicity for three ovotoxic agents, 4-vinylcyclohexene diepoxide (VCD), methoxychlor (MXC), and menadione (MEN), all of which target immature follicles. Microarray analysis of neonatal mouse ovaries exposed to these xenobiotics in vitro revealed a more than twofold significant difference in transcript expression (p < 0.05) for a number of genes associated with apoptotic cell death and primordial follicle activation. Histomorphological and immunohistological analysis supported the microarray data, showing signs of primordial follicle activation and preantral follicle atresia both in vitro and in vivo. Sperm-oocyte fusion assays on oocytes obtained from adult Swiss mice treated neonatally revealed severely reduced sperm-egg binding and fusion in a dose-dependent manner for all the xenobiotic treatments. Additionally, lipid peroxidation analysis on xenobiotic-cultured oocytes indicated a dose-dependent increase in oocyte lipid peroxidation for all three xenobiotics in vitro. Our results reveal a novel mechanism of preantral ovotoxicity involving the homeostatic recruitment of primordial follicles to maintain the pool of developing follicles destroyed by xenobiotic exposure and to our knowledge provide the first documented evidence of short-term, low- and high-dose (VCD 40-80 mg/kg/day, MXC 50-100 mg/kg/day, MEN 7.5-15 mg/kg/day) neonatal exposure to xenobiotics causing long-term reactive oxygen species-induced oocyte dysfunction.


Assuntos
Cicloexenos/toxicidade , Metoxicloro/toxicidade , Folículo Ovariano/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Compostos de Vinila/toxicidade , Vitamina K 3/toxicidade , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Análise em Microsséries , Técnicas de Cultura de Órgãos , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Interações Espermatozoide-Óvulo/fisiologia , Análise Serial de Tecidos
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