Targeted NGS gene panel identifies mutations in RSPH1 causing primary ciliary dyskinesia and a common mechanism for ciliary central pair agenesis due to radial spoke defects.

Primary ciliary dyskinesia (PCD) is an inherited chronic respiratory obstructive disease with randomized body laterality and infertility, resulting from cilia and sperm dysmotility. PCD is characterized by clinical variability and extensive genetic heterogeneity, associated with different cilia ultrastructural defects and mutations identified in >20 genes. Next generation sequencing (NGS) technologies therefore present a promising approach for genetic diagnosis which is not yet in routine use. We developed a targeted panel-based NGS pipeline to identify mutations by sequencing of selected candidate genes in 70 genetically undefined PCD patients. This detected loss-of-function RSPH1 mutations in four individuals with isolated central pair (CP) agenesis and normal body laterality, from two unrelated families. Ultrastructural analysis in RSPH1-mutated cilia revealed transposition of peripheral outer microtubules into the 'empty' CP space, accompanied by a distinctive intermittent loss of the central pair microtubules. We find that mutations in RSPH1, RSPH4A and RSPH9, which all encode homologs of components of the 'head' structure of ciliary radial spoke complexes identified in Chlamydomonas, cause clinical phenotypes that appear to be indistinguishable except at the gene level. By high-resolution immunofluorescence we identified a loss of RSPH4A and RSPH9 along with RSPH1 from RSPH1-mutated cilia, suggesting RSPH1 mutations may result in loss of the entire spoke head structure. CP loss is seen in up to 28% of PCD cases, in whom laterality determination specified by CP-less embryonic node cilia remains undisturbed. We propose this defect could arise from instability or agenesis of the ciliary central microtubules due to loss of their normal radial spoke head tethering

Primary Cilia: Highly Sophisticated Biological Sensors

Primary cilia, thin hair-like structures protruding from the apical surface of most mammalian cells, have gained the attention of many researchers over the past decade. Primary cilia are microtubule-filled sensory organelles that are enclosed within the ciliary membrane. They originate at the cell surface from the mother centriole that becomes the mature basal body. In this review, we will discuss recent literatures on the roles of cilia as sophisticated sensory organelles. With particular emphasis on vascular endothelia and renal epithelia, the mechanosensory role of cilia in sensing fluid shear stress will be discussed. Also highlighted is the ciliary involvement in cell cycle regulation, development, cell signaling and cancer. Finally, primary cilia-related disorders will be briefly described

The dynamic cilium in human diseases

Cilia are specialized organelles protruding from the cell surface of almost all mammalian cells. They consist of a basal body, composed of two centrioles, and a protruding body, named the axoneme. Although the basic structure of all cilia is the same, numerous differences emerge in different cell types, suggesting diverse functions. In recent years many studies have elucidated the function of 9+0 primary cilia. The primary cilium acts as an antenna for the cell, and several important pathways such as Hedgehog, Wnt and planar cell polarity (PCP) are transduced through it. Many studies on animal models have revealed that during embryogenesis the primary cilium has an essential role in defining the correct patterning of the body. Cilia are composed of hundreds of proteins and the impairment or dysfunction of one protein alone can cause complete loss of cilia or the formation of abnormal cilia. Mutations in ciliary proteins cause ciliopathies which can affect many organs at different levels of severity and are characterized by a wide spectrum of phenotypes. Ciliary proteins can be mutated in more than one ciliopathy, suggesting an interaction between proteins. To date, little is known about the role of primary cilia in adult life and it is tempting to speculate about their role in the maintenance of adult organs. The state of the art in primary cilia studies reveals a very intricate role. Analysis of cilia-related pathways and of the different clinical phenotypes of ciliopathies helps to shed light on the function of these sophisticated organelles. The aim of this review is to evaluate the recent advances in cilia function and the molecular mechanisms at the basis of their activity

LES of swirling flows in gas turbine combustion chambers

The flow and mixing in a swirl-stabilized gas-turbine burner is studied by Large Eddy Simulations (LES). Each swirler has a different mass flux and swirl angle. The interaction between neighbouring jets is studied, co-rotating and counter rotating jets are considered. Another issue of importance is related to the jet inlet conditions (e.g. axial distribution and levels of turbulence). In addition to the flow field (using LES) we present results related to fuel/air mixing under different conditions. We show that the LES results can resolve several issues related to the burner that cannot be accounted for by the standard RANS computations

Comparison of serum vascular endothelial growth factor in pre-eclamptic and normal pregnancies

OBJECTIVE: To determine whether pre-eclampsia is associated with alterations in maternal serum levels of vascular endothelial growth factor (VEGF), a mediator of endothelial cell growth and permeability. STUDY DESIGN: Samples of peripheral venous blood were obtained from 18 women with pre-eclampsia at term (37-42 weeks gestation) and from 18 controls matched for maternal age. gestational age, fetal weight, parity, and race Women with chronic hypertension, renal, or metabolic disease were excluded. Pre-eclampsia was classified as mild in 12 rases and as severe in 6. VEGF concentrations were measured in scrum samples using a sandwich Fl.ISA specific for YEGF (R £D Systems; Minneapolis, MN). Demographic and clinical data were anahzed with c2 analysis. \TGF levels were compared with the Mann-Whitney L test. RESULTS: Serum VEGF le\els were delectable (\u3e9 pM) in 11/18 pre-eclamptics and 11/18 controls (mean 163.7 ±24.7 pM, range 20-390 pM). \T,GF was detectable in 6/12 (50%) women with mild pre-eclampsia and in f\u3e/6 (83.?%) with severe pre-erlampsia. There were 8 matched pairs in which both study patients and their controls had detectable VF_GF levels. Among these, patients with preeclampsia had significantly higher \T.GF le\els than controls (135.4 ±89.5pM versus 29.8 ±3..\u3e ±102.8pM) were similar (P = 0.7) to the levels in severe preeclampsia (94 ±71.4pM). CONCLUSIONS: When detectable, serum VEGF levels are increased in patients with pre-eclampsia. Serum \T,GF levels are more likely to be detectable among patients with se\ere pre-eclampsia. Through ils ability to act as a mitogen for vascular endothelial cells, induction of vascular permeability, and promotion of coagulation, VEGF mav contribute to the endothelial cell activation characteristic of pre-eclampsia