Predictive Utility of the Multi-Process Action Control Framework for Self-Reported and Device-Measured Physical Activity Behavior of Adolescents.

Understanding the correlates of physical activity behavior is imperative for informing the development of interventions to address the low rates of physical activity guideline adherence among adolescents living in the United States. This cross-sectional study examined the predictive utility of the Multi-Process Action Control (M-PAC) framework for explaining self-reported and device-measured physical activity behavior among a Hispanic-majority sample of adolescents. A total of 1849 high school students (mean age = 16.

Out-of-school Activities and Adherence to 24-hour Movement Guidelines.

Introduction: The purpose of this study was to explore associations between participation in out-of-school/weekend organized activities and adherence to the 24-hour movement guidelines among US adolescents.

Methods: Data from the 2022 National Survey of Children's Health (N=16,403, age=15.1±1.

Predicting physical activity behavior among university students using the multi-process action control framework.

Most university students do not engage in enough physical activity (PA) despite the known physical and mental health benefits. Action control theories such as the Multi-Process Action Control (M-PAC) framework have been proposed to better understand the translation of intentions into action by incorporating post-intentional processes. However, the explanatory power of the M-PAC framework beyond traditional social cognitive constructs has received limited attention.

Exercise identity and physical activity behavior during late adolescence: A four wave cross-lagged panel model.

Research has shown that physical activity behavior tends to decline across adolescence before stabilizing in adulthood. Identifying salient factors underlying these behavioral changes is therefore imperative for informing intervention development. This study explored the temporal nature of the relationship between exercise identity and physical activity behavior during the transition out of high school.

Genetics in the X-Men film franchise: mutants as allegories of difference.

This article analyzes the complete corpus of live-action X-Men movies for their depictions of genetics and otherness. The researchers watched and qualitatively coded all thirteen movies produced by 20th Century Fox that take place in the same shared cinematic universe, beginning with (2000) and ending with (2020). The X-Men movies are unusual summer blockbusters since they explore genetic topics through their central characters, mutants, who are genetically different from their non-mutant peers.

A Pandora's box in feline medicine: presenting signs and surgical outcomes in 58 previously hoarded cats with chronic otitis media-interna.

Objectives: The aim of the present study was to report clinical findings, surgical complications and outcomes for previously hoarded cats treated surgically for otitis media-interna (OMI) and to investigate the risk factors for complications and poor outcomes.

Methods: A retrospective study was conducted of 58 cats from an institutional hoarding environment that underwent ventral bulla osteotomy (VBO).

Results: Inappetence was uncommon at presentation (9/58, 16%) compared with pruritus/alopecia (50%), nasopharyngeal signs (45%), otitis externa (OE) (79%) and otitis interna (OI) (ataxia ± head tilt/head excursions) in 40%.

24-hour movement guideline adherence and mental health: A cross-sectional study of emerging adults with chronic health conditions and disabilities.

Background: Recent work has shown that individuals with chronic health conditions and disabilities (CCD) meet the 24-h movement guidelines at lower rates than population norms; however, the evidence base remains limited across different stages of the lifespan and very few studies have examined associations with mental health outcomes.

Objective: This study examined 24-h movement guideline adherence among emerging adults with CCD compared to those without and associations between guideline adherence and indicators of mental health.

Methods: This cross-sectional study used data from the 2020 cycle of the Canadian Campus Wellbeing Survey.

Targeted retroviral gene delivery using ultrasound.

Background: Achieving specificity of delivery represents a major problem limiting the clinical application of retroviral vectors for gene therapy, whilst lack of efficiency and longevity of gene expression limit non-viral techniques. Ultrasound and microbubble contrast agents can be used to effect plasmid DNA delivery. We therefore sought to evaluate the potential for ultrasound/microbubble-mediated retroviral gene delivery.

Spatial and acoustic pressure dependence of microbubble-mediated gene delivery targeted using focused ultrasound.

Background: Ultrasound/microbubble-mediated gene delivery has the potential to be targeted to tissue deep in the body by directing the ultrasound beam following vector administration. Application of this technology would be minimally invasive and benefit from the widespread clinical experience of using ultrasound and microbubble contrast agents. In this study we evaluate the targeting ability and spatial distribution of gene delivery using focused ultrasound.

Primary attachment of murine leukaemia virus vector mediated by particle-associated heparan sulfate proteoglycan.

Target cell entry of murine leukaemia virus vectors proceeds via primary attachment, independent of the viral envelope protein and subsequent envelope-receptor interaction. Although much attention has been paid to modifying the latter for target cell specificity, the initial binding interaction has been overlooked, despite its opposing involvement both in providing the virus available for receptor binding and in depleting free virus. As a first step towards modifying primary attachment, both to provide specificity and to enhance vector availability, we sought to determine the nature of this interaction.

Physical parameters affecting ultrasound/microbubble-mediated gene delivery efficiency in vitro.

Ultrasound (US)/microbubble-mediated gene delivery is a technology with many potential advantages suited to clinical application. Previous studies have demonstrated transfection but many are unsatisfactory in respect to the exposure apparatus, lack of definition of the US field or the limitations on parameters that can be explored using clinical diagnostic US machines. We investigated individual exposure parameters using a system minimising experimental artefacts and allowing control of many parameters of the US field.

Complement insufficiency limits efficacy in a xenograft model of hyperacute rejection for cancer therapy.

Hyperacute rejection (HAR) is a rapid immunological response to an organ xenotransplant caused by recognition of endothelial galactose(alpha1,3)galactose (alphaGal) epitopes and complement-mediated cell lysis by host anti-alphaGal antibody ('natural antibody'). The alphaGal epitope is synthesised by a galactosyl transferase ((alpha1,3)GT) which humans lack. Because human cells transduced with (alpha1,3)GT are sensitised to natural antibody/complement-mediated lysis in human serum, delivery of (alpha1,3)GT to tumour vasculature in patients is a potential therapeutic strategy, by mimicking the pathophysiology of organ rejection.

Anti-alphaGal-dependent complement-mediated cytotoxicity in metastatic melanoma.

Antibodies to the cell surface disaccharide galactose(alpha1,3)galactose (alphaGal) are the most prevalent natural antibodies in human serum. The anti-alphaGal immunoglobulin M-dependent activation of complement causes hyperacute rejection of organ transplants from discordant species by human recipients. It has been shown in vitro that human tumour cells transduced with the gene that synthesizes alphaGal become sensitive to human serum.

Inactivation of murine leukaemia virus by exposure to visible light.

Prolonged storage of murine leukaemia virus in ambient light leads to a loss of infectivity. Particle integrity and envelope incorporation are unaffected; rather, the defect is functional and intrinsic to the viral core. Light in the violet part of the visible spectrum (wavelength 420-430 nm) is responsible for virus inactivation.

Mice are unsuitable for modelling ABO discordance despite strain-specific A cross-reactive natural IgM.

ABO blood group antigens are immunodominant cell surface oligosaccharides. The function of the ABO system is clinically important in blood transfusion and solid organ transplantation but there is no small animal model of ABO discordance. The present study demonstrated A glycoconjugate-reactive IgM in the serum of CBA/Ca mice by enzyme-linked immunosorbent assay but showed with sugar blocking that the specificity of this IgM was different from that of human anti-A IgM.

Transcriptional targeting of acute hypoxia in the tumour stroma is a novel and viable strategy for cancer gene therapy.

Deregulated tumour growth and neovascularization result in an inadequate tumour blood supply, leading to areas of chronic hypoxia and necrosis. Irregular vascular structure and abnormal tumour physiology also cause erratic blood flow in tumour vessels. We reasoned that tumour stroma, including vascular endothelial cells, would consequently experience transient hypoxia that may allow transcriptional targeting as part of an antivascular gene therapy approach to cancer.

In vivo efficacy of HSV-TK transcriptionally targeted to the tumour vasculature is augmented by combination with cytotoxic chemotherapy.

Background: Retroviral vectors are suitable for targeting endothelial cells in the tumour neovasculature because of their intrinsic selectivity for proliferating cells. Previously, we inserted regulatory elements of the endothelial-specific prepro-endothelin-1 (ppET1) promoter in retroviral vectors to generate high-titre, replication-defective recombinant retroviruses that restricted gene expression to the vascular compartment of tumours.

Methods: A retroviral vector was generated in which expression of herpes simplex virus thymidine kinase (HSV-TK) was transcriptionally restricted to endothelial cells, under the control of a hybrid ppET-1 LTR.

Retroviral hybrid LTR vector strategy: functional analysis of LTR elements and generation of endothelial cell specificity.

Transcriptional targeting is an important aspect of developing gene therapy vectors in order to restrict transgene expression to selected target cells. One approach, when using retroviral vectors, is to replace viral transcriptional control elements within the long terminal repeat (LTR) with sequences imparting the desired specificity. We have developed such hybrid LTR retroviruses, incorporating sequences from each of the human promoters for flt-1, ICAM-2 and KDR, as part of our antivascular cancer gene therapy strategy targeting tumour endothelial cells.

Rescue of retroviral envelope fusion deficiencies by cationic liposomes.

Background: Retroviral particles that are inappropriately enveloped can transduce target cells if pre-associated with cationic liposomes. This study optimises and addresses the mechanism of liposome-enhanced gene delivery, and explores the potential for such agents to compensate for fusion deficiency associated with chimaeric envelope proteins.

Methods: Particles bearing wild-type, chimaeric or no envelope proteins were complexed with DOTAP or DC-Chol/DOPE cationic liposomes and added to target cells for various times.

Reduced growth in response to ganciclovir treatment of subcutaneous xenografts expressing HSV-tk in the vascular compartment.

Using a recombinant retrovirus with ecotropic envelope we have achieved high efficiency of transduction of endothelial cells in the vasculature of subcutaneous xenografts arising from the co-injection of tumour cells and irradiated virus producers. We have used this experimental system to assess the efficacy of the herpes simplex virus-thymidine kinase (HSV-tk)/ganciclovir (GCV) prodrug activation system in anti-vascular therapy. Treatment of KSY-1 xenografts with HSV-tk transduction in the vascular compartment with the S-phase-dependent drug GCV resulted in extensive haemorrhagic necrosis, indicative of vascular damage.

Generation of a high titre retroviral vector for endothelial cell-specific gene expression in vivo.

Tumour growth is dependent upon a blood supply and is associated with the switch to the angiogenic phenotype. We are developing strategies for targeting gene expression to endothelial cells in the tumour vasculature. Recombinant retroviruses have been generated that incorporate regulatory sequences of the prepro-endothelin-1 (ppET1) promoter.

Emphysematous cholecystitis in a Siberian husky.

A 6-year-old, intact male Siberian husky was evaluated for a 24-hour history of vomiting and lethargy. Diagnosis of emphysematous cholecystitis was achieved based on survey abdominal radiographs, a barium contrast gastrointestinal series, and abdominal ultrasound. Diagnosis and medical and surgical management of the condition are discussed.