Sonic hedgehog signaling regulates processes of embryonic development across multiple tissues, yet factors regulating context-specific Shh signaling remain poorly understood. Exome sequencing of families with polymicrogyria (disordered cortical folding) revealed multiple individuals with biallelic deleterious variants in TMEM161B , which encodes a multi-pass transmembrane protein of unknown function. Tmem161b null mice demonstrated holoprosencephaly, craniofacial midline defects, eye defects, and spinal cord patterning changes consistent with impaired Shh signaling, but were without limb defects, suggesting a CNS-specific role of Tmem161b. Tmem161b depletion impaired the response to Smoothened activation in vitro and disrupted cortical histogenesis in vivo in both mouse and ferret models, including leading to abnormal gyration in the ferret model. Tmem161b localizes non-exclusively to the primary cilium, and scanning electron microscopy revealed shortened, dysmorphic, and ballooned ventricular zone cilia in the Tmem161b null mouse, suggesting that the Shh-related phenotypes may reflect ciliary dysfunction. Our data identify TMEM161B as a regulator of cerebral cortical gyration, as involved in primary ciliary structure, as a regulator of Shh signaling, and further implicate Shh signaling in human gyral development.
Preventive PCI versus culprit lesion stenting during primary PCI in acute STEMI: a systematic review and meta-analysis
Aim The benefit of preventive percutaneous coronary intervention (PCI) in ST elevation myocardial infarction (STEMI) has been shown in randomised trials. However, all the randomised trials are underpowered to detect benefit in cardiac death. We aim to systematically review evidence on the cardiac mortality benefit of preventive PCI in patients presenting with acute STEMI in randomised patient populations. Methods PubMed, Scopus, Cochrane and clinicaltrials.gov databases were searched for studies published until 30 September 2013. The studies were limited to randomised clinical trials. Independent observers abstracted the data on outcomes, characteristics and qualities of studies included. Fixed effect model was employed for meta-analysis. Heterogeneity of studies included was analysed using I2 statistics. Results In three randomised clinical trials published, involving 748 patients with acute STEMI and multivessel disease, 416 patients were randomised to preventive PCI and 332 to culprit-only PCI. Patients undergoing preventive PCI had significant lower risk of cardiovascular deaths (pooled OR 0.39, 95% CI 0.18 to 0.83, p=0.01, I2=0%), repeat revascularisation (pooled OR 0.28, 95% CI 0.18 to 0.44, p=0.00001, I2=0%) and non-fatal myocardial infarction (pooled OR 0.38, 95% CI 0.20 to 0.75, p=0.005, I2=0%) compared with culprit-only revascularisation. Conclusions In patients presenting with acute STEMI and significant multivessel coronary artery disease, based on our data, preventive PCI is associated with lower risk of cardiovascular mortality compared with primary PCI of only the culprit artery. This finding needs to be confirmed in larger adequately powered randomised clinical trials.