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1.
JMIR Res Protoc ; 13: e55960, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512336

RESUMO

BACKGROUND: Low levels of physical activity are associated with numerous adverse health outcomes, yet sedentary lifestyles are common among both children and adults. Physical activity levels tend to decline steeply among children aged between 8 and 12 years, even though children's behavioral patterns are largely governed by familial structures. Similarly, parents' activity levels have been generally reported as lower than those of nonparents of comparable age. For this reason, family-based physical activity promotion interventions are a potentially valuable and relatively underresearched method for mitigating physical activity declines as children develop into adolescents and for increasing physical activity in parents. OBJECTIVE: This study aims to assess the efficacy, feasibility, and acceptability of a novel theory-based web-based physical activity promotion intervention among parent-child dyads in Finland who do not meet physical activity recommendations at baseline. METHODS: Participants (target N=254) will be recruited from the general population using a panel company and advertisements on social media and randomly assigned to either an immediate intervention group or a waitlist control group. The intervention consists of 4 web-based group workshops over the course of 10 weeks, web-based tasks and resources, and a social support chat group. Data on physical activity behavior and constructs from the integrated behavior change model will be collected through self-report surveys assessing physical activity, autonomy support, autonomous motivation, attitude, subjective norm, perceived behavioral control, intention, self-monitoring, habit, and accelerometer measurements at baseline, post intervention, and 3 months post intervention. Exit interviews with participants will assess the feasibility and acceptability of the intervention procedures. RESULTS: This study will reveal whether the intervention changes leisure-time physical activity among intervention participants relative to the control group and will examine the intervention's effects on important theoretical predictors of physical activity. It will also yield data that can be used to refine intervention materials and inform further implementation. Trial recruitment commenced in September 2023, and data collection should be completed by December 2024. CONCLUSIONS: The planned intervention has potential implications for both theory and practice. Practically, the use of an entirely web-based intervention may have scalable future uses for improving physical activity in 2 key populations, while also potentially informing on the value of dyadic, family-based strategies for encouraging an active lifestyle as an alternative to strategies that target either parents or children independently. Further, by assessing change in psychological constructs alongside potential change in behavior, the intervention also allows for important tests of theory regarding which constructs are most linked to favorable behavior change outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT06070038; https://clinicaltrials.gov/study/NCT06070038. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/55960.

2.
Viruses ; 15(5)2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37243219

RESUMO

The ongoing emergence of SARS-CoV-2 virus variants remains a source of concern because it is accompanied by the potential for increased virulence as well as evasion of immunity. Here we show that, although having an almost identical spike gene sequence as another Omicron variant (BA.5.2.1), a BA.4 isolate lacked all the typical disease characteristics of other isolates seen in the Golden Syrian hamster model despite replicating almost as effectively. Animals infected with BA.4 had similar viral shedding profiles to those seen with BA.5.2.1 (up to day 6 post-infection), but they all failed to lose weight or present with any other significant clinical signs. We hypothesize that this lack of detectable signs of disease during infection with BA.4 was due to a small (nine nucleotide) deletion (∆686-694) in the viral genome (ORF1ab) responsible for the production of non-structural protein 1, which resulted in the loss of three amino acids (aa 141-143).


Assuntos
COVID-19 , Animais , Cricetinae , SARS-CoV-2/genética , Mesocricetus , Aminoácidos , Glicoproteína da Espícula de Coronavírus/genética
3.
PLoS Pathog ; 19(4): e1011293, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014911

RESUMO

The mutation profile of the SARS-CoV-2 Omicron (lineage BA.1) variant posed a concern for naturally acquired and vaccine-induced immunity. We investigated the ability of prior infection with an early SARS-CoV-2 ancestral isolate (Australia/VIC01/2020, VIC01) to protect against disease caused by BA.1. We established that BA.1 infection in naïve Syrian hamsters resulted in a less severe disease than a comparable dose of the ancestral virus, with fewer clinical signs including less weight loss. We present data to show that these clinical observations were almost absent in convalescent hamsters challenged with the same dose of BA.1 50 days after an initial infection with ancestral virus. These data provide evidence that convalescent immunity against ancestral SARS-CoV-2 is protective against BA.1 in the Syrian hamster model of infection. Comparison with published pre-clinical and clinical data supports consistency of the model and its predictive value for the outcome in humans. Further, the ability to detect protection against the less severe disease caused by BA.1 demonstrates continued value of the Syrian hamster model for evaluation of BA.1-specific countermeasures.


Assuntos
COVID-19 , Animais , Cricetinae , Humanos , Convalescença , Mesocricetus , SARS-CoV-2
4.
Viruses ; 15(3)2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36992342

RESUMO

In the summer of 2020, it became clear that the genetic composition of SARS-CoV-2 was changing rapidly. This was highlighted by the rapid emergence of the D614G mutation at that time. In the autumn of 2020, the project entitled "Agility" was initiated with funding from the Coalition for Epidemic Preparedness Innovations (CEPI) to assess new variants of SARS-CoV-2. The project was designed to reach out and intercept swabs containing live variant viruses in order to generate highly characterised master and working stocks, and to assess the biological consequences of the rapid genetic changes using both in vitro and in vivo approaches. Since November 2020, a total of 21 variants have been acquired and tested against either a panel of convalescent sera from early in the pandemic, and/or a panel of plasma from triple-vaccinated participants. A pattern of continuous evolution of SARS-CoV-2 has been revealed. Sequential characterisation of the most globally significant variants available to us, generated in real-time, indicated that the most recent Omicron variants appear to have evolved in a manner that avoids immunological recognition by convalescent plasma from the era of the ancestral virus when analysed in an authentic virus neutralisation assay.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Soroterapia para COVID-19 , Mutação , Pandemias , Anticorpos Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
5.
Viruses ; 15(3)2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36992457

RESUMO

The golden Syrian hamster (Mesocricetus auratus) is now commonly used in preclinical research for the study of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the assessment of vaccines, drugs and therapeutics. Here, we show that hamsters inoculated via the intranasal route with the same infectious virus dose of prototypical SARS-CoV-2 administered in a different volume present with different clinical signs, weight loss and viral shedding, with a reduced volume resulting in reduced severity of disease similar to that obtained by a 500-fold reduction in the challenge dose. The tissue burden of the virus and the severity of pulmonary pathology were also significantly affected by different challenge inoculum volumes. These findings suggest that a direct comparison between the severity of SARS-CoV-2 variants or studies assessing the efficacy of treatments determined by hamster studies cannot be made unless both the challenge dose and inoculation volume are matched when using the intranasal route. Additionally, analysis of sub-genomic and total genomic RNA PCR data demonstrated no link between sub-genomic and live viral titres and that sub-genomic analyses do not provide any information beyond that provided by more sensitive total genomic PCR.


Assuntos
COVID-19 , Cricetinae , Animais , Humanos , Mesocricetus , COVID-19/patologia , SARS-CoV-2 , Pulmão , Gravidade do Paciente , Modelos Animais de Doenças
6.
J Biomed Opt ; 15(4): 046014, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20799816

RESUMO

Cavernous nerves course along the surface of the prostate gland and are responsible for erectile function. These nerves are at risk of injury during surgical removal of a cancerous prostate gland. In this work, a combination of segmentation, denoising, and edge detection algorithms are applied to time-domain optical coherence tomography (OCT) images of rat prostate to improve identification of cavernous nerves. First, OCT images of the prostate are segmented to differentiate the cavernous nerves from the prostate gland. Then, a locally adaptive denoising algorithm using a dual-tree complex wavelet transform is applied to reduce speckle noise. Finally, edge detection is used to provide deeper imaging of the prostate gland. Combined application of these three algorithms results in improved signal-to-noise ratio, imaging depth, and automatic identification of the cavernous nerves, which may be of direct benefit for use in laparoscopic and robotic nerve-sparing prostate cancer surgery.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Nervos Periféricos/anatomia & histologia , Próstata/anatomia & histologia , Próstata/inervação , Tomografia de Coerência Óptica/métodos , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
J Biomed Opt ; 14(4): 044033, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19725744

RESUMO

The cavernous nerves course along the surface of the prostate and are responsible for erectile function. Improvements in identification, imaging, and visualization of the cavernous nerves during prostate cancer surgery may improve nerve preservation and postoperative sexual potency. Two-dimensional (2-D) optical coherence tomography (OCT) images of the rat prostate were segmented to differentiate the cavernous nerves from the prostate gland. To detect these nerves, three image features were employed: Gabor filter, Daubechies wavelet, and Laws filter. The Gabor feature was applied with different standard deviations in the x and y directions. In the Daubechies wavelet feature, an 8-tap Daubechies orthonormal wavelet was implemented, and the low-pass sub-band was chosen as the filtered image. Last, Laws feature extraction was applied to the images. The features were segmented using a nearest-neighbor classifier. N-ary morphological postprocessing was used to remove small voids. The cavernous nerves were differentiated from the prostate gland with a segmentation error rate of only 0.058+/-0.019. This algorithm may be useful for implementation in clinical endoscopic OCT systems currently being studied for potential intraoperative diagnostic use in laparoscopic and robotic nerve-sparing prostate cancer surgery.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Pênis/inervação , Nervos Periféricos/anatomia & histologia , Próstata/anatomia & histologia , Técnica de Subtração , Tomografia de Coerência Óptica/métodos , Animais , Aumento da Imagem/métodos , Masculino , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Sex Med ; 5(11): 2713-5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18761594

RESUMO

INTRODUCTION: Cylinder aneurysms and leakages are uncommon with three-layered American Medical System (AMS) CX cylinders. Since 2001, an additional parylene coating improves cylinder wear. AIM: To report two patients in whom major cylinder aneurysms developed less than 4 years after implantation. METHODS: Two patients in separate urologic private practices developed significant cylinder aneurysms requiring reoperation. RESULTS: Both patients developed aneurysms in 21-cm parylene-coated CX cylinders just short of 4 years of inflatable penile prosthesis (IPP) placement. Both did well after the explantation and insertion of Coloplast Titan IPP (Coloplast; Minneapolis, MN, USA). CONCLUSION: Longer AMS CX IPP cylinders may develop aneurysms more than 3 years after insertion.


Assuntos
Materiais Revestidos Biocompatíveis , Disfunção Erétil/cirurgia , Prótese de Pênis , Polímeros , Falha de Prótese , Xilenos , Idoso , Disfunção Erétil/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese
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