Antisense oligonucleotide inhibition of Bcl-xL and Bid expression in liver regulates responses in a mouse model of Fas-induced fulminant hepatitis

Activation of the cell-surface receptor Fas can lead to apoptosis in parenchymal cells in the liver, and if severe enough, result in fulminant hepatic failure and animal death. In the present study, we have examined the roles played by the Bcl-2 family members Bcl-xL and Bid in regulating this response. To do this, we have developed chemically modified 2'-O-(2-methoxy) ethyl antisense inhibitors of both Bid and Bcl-xL expression. In Balb/c mice, dosing with these antisense oligonucleotides reduced expression of the targeted mRNA by greater than 80% in the liver. This reduction was highly dependent upon oligonucleotide sequence and oligonucleotide dose. Reduction of Bcl-xL expression resulted in a potentiation of Fas-mediated apoptosis in liver and significant increase of the lethality of Fas-mediated fulminant hepatitis (p < 0.0001). In contrast, reduction of Bid expression protected the animals against Fas-mediated fulminant hepatitis and death (p < 0.0001). Simultaneous dosing of mice with Bcl-xL and Bid-targeting antisense oligonucleotides resulted in an inhibition of expression of both targeted proteins and protection of the animals from Fas-mediated apoptosis. These results demonstrate, for the first time, the role of Bcl-xL in regulating responses to proapoptotic Fas signaling in mouse liver. In addition, this is the first reported example demonstrating the ability of antisense inhibitors to reduce expression of multiple proteins in animals by simultaneous dosing.     

A hypermorphic IkappaBalpha mutation is associated with autosomal dominant anhidrotic ectodermal dysplasia and T cell immunodeficiency

X-linked anhidrotic ectodermal dysplasia with immunodeficiency (XL-EDA-ID) is caused by hypomorphic mutations in the gene encoding NEMO/IKKgamma, the regulatory subunit of the IkappaB kinase (IKK) complex. IKK normally phosphorylates the IkappaB-inhibitors of NF-kappaB at specific serine residues, thereby promoting their ubiquitination and degradation by the proteasome. This allows NF-kappaB complexes to translocate into the nucleus where they activate their target genes. Here, we describe an autosomal-dominant (AD) form of EDA-ID associated with a heterozygous missense mutation at serine 32 of IkappaBalpha. This mutation is gain-of-function, as it enhances the inhibitory capacity of IkappaBalpha by preventing its phosphorylation and degradation, and results in impaired NF-kappaB activation. The developmental, immunologic, and infectious phenotypes associated with hypomorphic NEMO and hypermorphic IKBA mutations largely overlap and include EDA, impaired cellular responses to ligands of TIR (TLR-ligands, IL-1beta, and IL-18), and TNFR (TNF-alpha, LTalpha1/beta2, and CD154) superfamily members and severe bacterial diseases. However, AD-EDA-ID but not XL-EDA-ID is associated with a severe and unique T cell immunodeficiency. Despite a marked blood lymphocytosis, there are no detectable memory T cells in vivo, and naive T cells do not respond to CD3-TCR activation in vitro. Our report highlights both the diversity of genotypes associated with EDA-ID and the diversity of immunologic phenotypes associated with mutations in different components of the NF-kappaB signaling pathway.     

Ventilator-associated events in children: A review of literature

Background

The complexity and variation in ventilator associated pneumonia (VAP) definitions in paediatrics may pose threats to the reliable identification of VAP. The revision of the surveillance definition to ventilator-associated event (VAE) has been mandated in adult populations, to overcome these issues. However, the evidence for application of the definition is unknown in children.

Influence of caffeine on frequency of hypoglycemia detected by continuous interstitial glucose monitoring system in patients with long-standing type 1 diabetes

OBJECTIVE: The aim of this study was to investigate the effect of caffeine (in doses equivalent to normal daily ingestion) on rates and severity of hypoglycemia in patients with long-standing type 1 diabetes to determine the relationship between caffeine, autonomic function, and hypoglycemia. RESEARCH DESIGN AND METHODS: Using a double-blinded randomized study, we investigated the effect of caffeine versus placebo in 19 patients with long-standing type 1 diabetes using continuous glucose sensing technology and simultaneous assessment of autonomic function using Holter monitoring. RESULTS: Caffeine reduced the duration of nocturnal hypoglycemia with a mean duration of 49 minutes (range 0-235) versus 132 (0-468) minutes (P = 0.035). The reduction in duration of nighttime hypoglycemia was due to a decline in the number of episodes of moderate hypoglycemia at the expense of mild hypoglycemic episodes (P = 0.04). There was no overall correlation between reduced heart rate variability (a marker of autonomic dysfunction) and hypoglycemic events (r(s) = 0.12, P = 0.62). CONCLUSIONS: Our results suggest that caffeine is associated with a significant reduction in nocturnal hypoglycemia. The reduction in nocturnal hypoglycemia was not linked to the concomitant rise in parasympathetic activity associated with caffeine.     

Robotic gastric bypass is getting better: first results from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program

Background

The use of robotic platforms in performing laparoscopic Roux-en-Y gastric bypass (LRYGB) is increasing, though their safety compared with the conventional laparoscopic approach remains unclear.

Advice for the management of low back pain: a systematic review of randomised controlled trials

To synthesise the evidence relating to the effectiveness of advice, the relevance of its content and frequency, and to compare the advice being offered to acute, subacute and chronic low back pain (LBP) patients. A systematic review of Randomised Controlled Trials (RCTs) using advice, either alone or with another intervention. The QUOROM guidelines and the Cochrane Collaboration Back Review Group Guidelines for Systematic Reviews were followed throughout: methodological assessment identified RCTs of ‘high’ or ‘medium’ methodological quality, based on their inclusion of at least 50% of the specified internal validity criteria. Outcome measures were analysed based on five recommended core outcome domains; pain, work disability, back-specific function, generic health status and satisfaction with care. Relevant RCTs (n=56) were scored for methodological quality; 39 RCTs involving 7347 patients qualified for inclusion, based upon their methodological quality. Advice as an adjunct to exercise was most effective for improving pain, back-specific function and work disability in chronic LBP but, for acute LBP, was no more effective for improving these outcomes than simple advice to stay active. Advice as part of a back school was most effective for improving back-specific function in subacute LBP; these trials generally demonstrated long-term positive results. Advice as an adjunct to exercise was the most common form of treatment for acute and chronic LBP; advice as part of a back school was most commonly used for subacute LBP. Fifteen percent of acute LBP trials had a positive outcome, compared to 86% and 74% of subacute and chronic LBP trials respectively. A wide variety of outcome measures were used, making valid comparisons between treatment outcomes difficult. The advice provided to patients with LBP within RCTs varied considerably depending on symptom duration. The findings of this review have important implications for clinical practice, and for the design of further clinical trials in this area. Advice to stay active is sufficient for acute LBP; however, it appears that RCTs do not commonly reflect these recommendations. No conclusions could be drawn as to the content and frequency of advice that is most effective for subacute LBP, due to the limited number and poor quality of RCTs in this area: this review provides preliminary support for advice as part of a back school approach. Given that the effectiveness of treatment for subacute symptoms will directly influence the development of chronicity, these results would suggest that education and awareness of the causes and consequences of back pain may be a valuable treatment component for this patient subgroup. For chronic LBP there is strong evidence to support the use of advice to remain active in addition to specific advice relating to the most appropriate exercise, and/or functional activities to promote active self-management. More investigation is needed into the role of follow-up advice for chronic LBP patients.