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Background

The development and use of Web-based programs for weight loss is increasing rapidly, yet they have rarely been evaluated using randomized controlled trials (RCTs). Interestingly, most people who attempt weight loss use commercially available programs, yet it is very uncommon for commercial programs to be evaluated independently or rigorously.

Objective

To compare the efficacy of a standard commercial Web-based weight-loss program (basic) versus an enhanced version of this Web program that provided additional personalized e-feedback and contact from the provider (enhanced) versus a wait-list control group (control) on weight outcomes in overweight and obese adults.

Methods

This purely Web-based trial using a closed online user group was an assessor-blinded RCT with participants randomly allocated to the basic or enhanced 12-week Web-based program, based on social cognitive theory, or the control, with body mass index (BMI) as the primary outcome.

Results

We enrolled 309 adults (129/309, 41.8% male, BMI mean 32.3, SD 4 kg/m2) with 84.1% (260/309) retention at 12 weeks. Intention-to-treat analysis showed that both intervention groups reduced their BMI compared with the controls (basic: –0.72, SD 1.1 kg/m2, enhanced: –1.0, SD 1.4, control: 0.15, SD 0.82; P < .001) and lost significant weight (basic: –2.1, SD 3.3 kg, enhanced: –3.0, SD 4.1, control: 0.4, SD 2.3; P < .001) with changes in waist circumference (basic: –2.0, SD 3.5 cm, enhanced: –3.2, SD 4.7, control: 0.5, SD 3.0; P < .001) and waist-to-height ratio (basic: –0.01, SD 0.02, enhanced: –0.02, SD 0.03, control: 0.0, SD 0.02; P < .001), but no differences were observed between the basic and enhanced groups. The addition of personalized e-feedback and contact provided limited additional benefits compared with the basic program.

Conclusions

A commercial Web-based weight-loss program can be efficacious across a range of weight-related outcomes and lifestyle behaviors and achieve clinically important weight loss. Although the provision of additional personalized feedback did not facilitate greater weight loss after 12 weeks, the impact of superior participant retention on longer-term outcomes requires further study. Further research is required to determine the optimal mix of program features that lead to the biggest treatment impact over time.

Trial Registration

Australian New Zealand Clinical Trials Registry (ANZCTR): 12610000197033; http://www.anzctr.org.au/trial_view.aspx?id=335159 (Archived by WebCite at http://www.webcitation.org/66Wq0Yb7U)  相似文献   
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The hydrophobic plasma membrane constitutes an indispensable barrier for cells, allowing influx of essential molecules while preventing access to other macromolecules. Although pivotal for the maintenance of cells, the inability to cross the plasma membrane is one of the major obstacles toward current drug development. Oligonucleotides (ONs) are a group of substances that display great therapeutic potential to interfere with gene expression. Several classes of ONs have emerged either based on double stranded RNAs, such as short interfering RNAs that are utilized to confer gene silencing, or single stranded ONs of various chemistries for antisense targeting of small regulatory micro RNAs or mRNAs. In particular the use of splice switching oligonucleotides (SSOs) to manipulate alternative splicing, by targeting pre-mRNA, has proven to be a highly promising therapeutic strategy to treat various genetic disorders, including Duchenne muscular dystrophy and spinal muscular atrophy. Despite being efficient compounds to alter splicing patterns, their hydrophilic macromolecular nature prohibits efficient cellular internalization.Various chemical drug delivery vehicles have been developed aiming at improving the bioavailability of nucleic acid-based drugs. In the context of SSOs, one group of peptidebased delivery vectors, i.e. cell-penetrating peptides (CPPs), display extremely high potency. CPPs have a remarkable ability to convey various, otherwise impermeable, macromolecules across the plasma membrane of cells in a relatively non-toxic fashion. This review provides insight into the application of CPPs and ONs in gene regulation with particular focus on CPP-assisted delivery of therapeutic SSOs.  相似文献   
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In motor adaptation, the occurrence of savings (faster relearning of a previously learned motor adaptation task) has been explained in terms of operant reinforcement learning (Huang et al. in Neuron 70(4):787–801, 2011), which is thought to associate an adapted motor command with outcome success during repeated execution of the adapted movement. There is some evidence for deficient savings in Parkinson’s Disease (PD), which might result from deficient operant reinforcement processes. However, this evidence is compromised by limited adaptation training during initial learning and by multi-target adaptation, which reduces the number of reinforced movement repetitions for each target. Here, we examined savings in PD patients and controls following overlearning with a single target. PD patients showed less savings than controls after successive adaptation and deadaptation blocks within the same test session, as well as less savings across test sessions separated by a 24-h delay. It is argued that impaired blunted dopaminergic signals in PD impairs the modulation of dopaminergic signals to the motor cortex in response to rewarding motor outcomes, thus impairing the association of the adapted motor command with rewarding motor outcomes. Consequently, the previously adapted motor command is not preferentially selected during relearning, and savings is impaired.  相似文献   
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A 7-month-old, male eclectus parrot (Eclectus roratus roratus) was presented with a slow-growing mass over the chest and localized self-trauma to the area. Repeated sternal trauma secondary to an improper wing trim was observed in this case before development of the lesion. Surgical excision of the mass was performed for diagnostic and treatment purposes. On histopathologic examination, the mass was characterized by well-differentiated trabecular bone surrounded by a thin layer of periosteum. These findings were consistent with, but not exclusive to, a diagnosis of osteoma. This benign bone lesion is rare in human and veterinary medicine, with even fewer reports of this condition in avian patients. Trauma to the sternum from falling because of wing clipping was the most likely inciting cause in this parrot.  相似文献   
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