Explore the vast range of titles available.

Background Several small molecule corrector and potentiator drugs have recently been licensed for Cystic Fibrosis (CF) therapy. However, other aspects of the disease, especially inflammation, are less effectively treated by these drugs. We hypothesized that small molecule drugs could function either alone or as an adjuvant to licensed therapies to treat these aspects of the disease, perhaps emulating the effects of gene therapy in CF cells. The cardiac glycoside digitoxin, which has been shown to inhibit TNFα/NFκB signaling in CF lung epithelial cells, may serve as such a therapy. Methods IB3–1 CF lung epithelial cells were treated with different Vertex (VX) drugs, digitoxin, and various drug mixtures, and ELISA assays were used to assess suppression of baseline and TNFα-activated secretion of cytokines and chemokines. Transcriptional responses to these drugs were assessed by RNA-seq and compared with gene expression in AAV-[ wildtype ]CFTR-treated IB3–1 (S9) cells. We also compared in vitro gene expression signatures with in vivo data from biopsied nasal epithelial cells from digitoxin-treated CF patients. Results CF cells exposed to digitoxin exhibited significant suppression of both TNFα/NFκB signaling and downstream secretion of IL-8, IL-6 and GM-CSF, with or without co-treatment with VX drugs. No evidence of drug-drug interference was observed. RNA-seq analysis showed that gene therapy-treated CF lung cells induced changes in 3134 genes. Among these, 32.6% were altered by digitoxin treatment in the same direction. Shared functional gene ontology themes for genes suppressed by both digitoxin and gene therapy included inflammation (84 gene signature), and cell-cell interactions and fibrosis (49 gene signature), while genes elevated by both were enriched for epithelial differentiation (82 gene signature). A new analysis of mRNA data from digitoxin-treated CF patients showed consistent trends in expression for genes in these signatures. Conclusions Adjuvant gene therapy-emulating activities of digitoxin may contribute to enhancing the efficacy of currently licensed correctors and potentiators in CF patients.

Hemophilia A and B coagulation defects, which are caused by deficiencies of Factor VIII and Factor IX, respectively, can be bypassed by administration of recombinant Factor VIIa. However, the short half-life of recombinant Factor VIIa in vivo negates its routine clinical use. We report here an in vivo method for the continuous generation of Factor VIIa. The method depends on the implantation of a porous chamber that contains Factor Xa or XIIa, and continuously generates Factor VIIa bypass activity from the subject's own Factor VII, which enters the chamber by diffusion. Once inside, the Factor VII is cleaved to Factor VIIa by the immobilized Factor Xa or XIIa. The newly created Factor VIIa diffuses out of the chamber and back into the circulation, where it can bypass the deficient Factors VIII or IX, and enable coagulation to occur. In vitro, this method generates sufficient Factor VIIa to substantially correct Factor VIII-deficient plasma when assessed by the classical aPTT coagulation assay. In vivo, a Factor XIIa peritoneal implant generates bypass activity for up to one month when tested in rhesus monkeys. Implantation of such a chamber in a patient with hemophilia A or B could eventually provide a viable alternative to replacement therapies using exogenous coagulation factors.

THE sensation of depth that is obtained with human binocular vision results from the differences in the projection of the world onto the two retinae. The process entails solving the problem of stereo correspondence, which involves choosing the correct matches between left and right image features. Many computational models of stereo vision assume a uniqueness constraint on stereo matching—that is, each feature identified in one image should eventually be matched with only one feature in the other image 1,2 . This constraint would seem to be justified, as allowing non-unique matches would be tantamount to supposing that the scene entities to which matches relate are in two places at once 1 . The value of the uniqueness constraint for eliminating false matches has been demonstrated in a variety of stereo algorithms. Yet on the basis of psychophysical results Weinshall 3 concluded that it was not used by humans in dealing with certain types of ambiguous random-dot stereograms. We have now tested how Weinshall's stereograms are dealt with by PMF 4 , a stereo algorithm which uses a unique-matches selection procedure in conjunction with a purely local similar-disparity support scheme. We found that PMF produces results that are closely analogous to the psychophysical results. This suggests that Weishall's experiments should not be interpreted as evidence that the human stereo mechanism establishes non-unique matches.

Cystic fibrosis (CF) is a fatal, autosomal, recessive genetic disease that is characterized by profound lung inflammation. The inflammatory process is believed to be caused by massive overproduction of the proinflammatory protein IL-8, and the high levels of IL-8 in the CF lung are therefore believed to be the central mechanism behind CF lung pathophysiology. We show here that digitoxin, at sub nM concentrations, can suppress hypersecretion of IL-8 from cultured CF lung epithelial cells. Certain other cardiac glycosides are also active but with much less potency. The specific mechanism of digitoxin action is to block phosphorylation of the inhibitor of NF-κB (IκBα). IκBα phosphorylation is a required step in the activation of the NF-κB signaling pathway and the subsequent expression of IL-8. Digitoxin also has effects on global gene expression in CF cells. Of the informative genes expressed by the CF epithelial cell line IB-3, 58 are significantly (P < 0.05) affected by gene therapy with wild-type (CFTR CF transmembrane conductance regulator). Of these 58 genes, 36 (62%) are similarly affected by digitoxin and related active analogues. We interpret this result to suggest that digitoxin can also partially mimic the genomic consequences of gene therapy with CF transmembrane conductance regulator. We therefore suggest that digitoxin, with its lengthy history of human use, deserves consideration as a candidate drug for suppressing IL-8-dependent lung inflammation in CF.

New Arp2/3 complex inhibitors The actin cytoskeleton is dynamic and plays a critical role in several cell biological processes such as cell adhesion, migration and endocytosis. In addition, several pathogens exploit this system to invade and survive within host cells. The Arp2/3 complex nucleates actin filaments and has a unique property to form branched actin networks. In this study, Nolen et al . describe the generation of two types of small molecules that bind to different sites on the Arp2/3 complex and inhibit its actin nucleating activity in vitro and in vivo . These inhibitors provide a powerful approach to study Arp2/3 complex-mediated actin reorganization events in living cells. The actin cytoskeleton plays a critical role in cell biological processes such as cell adhesion, migration and endocytosis. Polymerization of actin filaments directed by the actin-related protein (Arp)2/3 complex supports many types of cellular movement. Two classes of small molecules that bind to different sites on the Arp2/3 complex and inhibit its ability to nucleate actin filaments are now described; these inhibitors provide a powerful approach for studying the Arp2/3 complex in living cells. Polymerization of actin filaments directed by the actin-related protein (Arp)2/3 complex supports many types of cellular movements 1 . However, questions remain regarding the relative contributions of Arp2/3 complex versus other mechanisms of actin filament nucleation to processes such as path finding by neuronal growth cones; this is because of the lack of simple methods to inhibit Arp2/3 complex reversibly in living cells. Here we describe two classes of small molecules that bind to different sites on the Arp2/3 complex and inhibit its ability to nucleate actin filaments. CK-0944636 binds between Arp2 and Arp3, where it appears to block movement of Arp2 and Arp3 into their active conformation. CK-0993548 inserts into the hydrophobic core of Arp3 and alters its conformation. Both classes of compounds inhibit formation of actin filament comet tails by Listeria and podosomes by monocytes. Two inhibitors with different mechanisms of action provide a powerful approach for studying the Arp2/3 complex in living cells.

Background Autism spectrum disorders (ASD) are complex neurobiological disorders that impair social interactions and communication and lead to restricted, repetitive, and stereotyped patterns of behavior, interests, and activities. The causes of these disorders remain poorly understood, but gut microbiota, the 10 13 bacteria in the human intestines, have been implicated because children with ASD often suffer gastrointestinal (GI) problems that correlate with ASD severity. Several previous studies have reported abnormal gut bacteria in children with ASD. The gut microbiome-ASD connection has been tested in a mouse model of ASD, where the microbiome was mechanistically linked to abnormal metabolites and behavior. Similarly, a study of children with ASD found that oral non-absorbable antibiotic treatment improved GI and ASD symptoms, albeit temporarily. Here, a small open-label clinical trial evaluated the impact of Microbiota Transfer Therapy (MTT) on gut microbiota composition and GI and ASD symptoms of 18 ASD-diagnosed children. Results MTT involved a 2-week antibiotic treatment, a bowel cleanse, and then an extended fecal microbiota transplant (FMT) using a high initial dose followed by daily and lower maintenance doses for 7–8 weeks. The Gastrointestinal Symptom Rating Scale revealed an approximately 80% reduction of GI symptoms at the end of treatment, including significant improvements in symptoms of constipation, diarrhea, indigestion, and abdominal pain. Improvements persisted 8 weeks after treatment. Similarly, clinical assessments showed that behavioral ASD symptoms improved significantly and remained improved 8 weeks after treatment ended. Bacterial and phagedeep sequencing analyses revealed successful partial engraftment of donor microbiota and beneficial changes in the gut environment. Specifically, overall bacterial diversity and the abundance of Bifidobacterium , Prevotella , and Desulfovibrio among other taxa increased following MTT, and these changes persisted after treatment stopped (followed for 8 weeks). Conclusions This exploratory, extended-duration treatment protocol thus appears to be a promising approach to alter the gut microbiome and virome and improve GI and behavioral symptoms of ASD. Improvements in GI symptoms, ASD symptoms, and the microbiome all persisted for at least 8 weeks after treatment ended, suggesting a long-term impact. Trial registration This trial was registered on the ClinicalTrials.gov, with the registration number  NCT02504554