TFAP2 paralogs regulate midfacial development in part through a conserved ALX genetic pathway.

Cranial neural crest development is governed by positional gene regulatory networks (GRNs). Fine-tuning of the GRN components underlies facial shape variation, yet how those networks in the midface are connected and activated remain poorly understood. Here, we show that concerted inactivation of Tfap2a and Tfap2b in the murine neural crest, even during the late migratory phase, results in a midfacial cleft and skeletal abnormalities. Bulk and single-cell RNA-seq profiling reveal that loss of both TFAP2 family members dysregulates numerous midface GRN components involved in midface morphogenesis, patterning and differentiation. Notably, Alx1, Alx3 and Alx4 (ALX) transcript levels are reduced, whereas ChIP-seq analyses suggest TFAP2 family members directly and positively regulate ALX gene expression. Tfap2a, Tfap2b and ALX co-expression in midfacial neural crest cells of both mouse and zebrafish implies conservation of this regulatory axis across vertebrates. Consistent with this notion, tfap2a zebrafish mutants present with abnormal alx3 expression patterns, Tfap2a binds ALX loci and tfap2a-alx3 genetic interactions are observed. Together, these data demonstrate TFAP2 paralogs regulate vertebrate midfacial development in part by activating expression of ALX transcription factor genes.

FaceBase 3: analytical tools and FAIR resources for craniofacial and dental research.

The FaceBase Consortium was established by the National Institute of Dental and Craniofacial Research in 2009 as a 'big data' resource for the craniofacial research community. Over the past decade, researchers have deposited hundreds of annotated and curated datasets on both normal and disordered craniofacial development in FaceBase, all freely available to the research community on the FaceBase Hub website. The Hub has developed numerous visualization and analysis tools designed to promote integration of multidisciplinary data while remaining dedicated to the FAIR principles of data management (findability, accessibility, interoperability and reusability) and providing a faceted search infrastructure for locating desired data efficiently. Summaries of the datasets generated by the FaceBase projects from 2014 to 2019 are provided here. FaceBase 3 now welcomes contributions of data on craniofacial and dental development in humans, model organisms and cell lines. Collectively, the FaceBase Consortium, along with other NIH-supported data resources, provide a continuously growing, dynamic and current resource for the scientific community while improving data reproducibility and fulfilling data sharing requirements.

The TFAP2A-IRF6-GRHL3 genetic pathway is conserved in neurulation.

Mutations in IRF6, TFAP2A and GRHL3 cause orofacial clefting syndromes in humans. However, Tfap2a and Grhl3 are also required for neurulation in mice. Here, we found that homeostasis of Irf6 is also required for development of the neural tube and associated structures. Over-expression of Irf6 caused exencephaly, a rostral neural tube defect, through suppression of Tfap2a and Grhl3 expression. Conversely, loss of Irf6 function caused a curly tail and coincided with a reduction of Tfap2a and Grhl3 expression in tail tissues. To test whether Irf6 function in neurulation was conserved, we sequenced samples obtained from human cases of spina bifida and anencephaly. We found two likely disease-causing variants in two samples from patients with spina bifida. Overall, these data suggest that the Tfap2a-Irf6-Grhl3 genetic pathway is shared by two embryologically distinct morphogenetic events that previously were considered independent during mammalian development. In addition, these data suggest new candidates to delineate the genetic architecture of neural tube defects and new therapeutic targets to prevent this common birth defect.

Diagnostic delay in pulmonary arterial hypertension: Insights from the Australian and New Zealand pulmonary hypertension registry.

BACKGROUND AND OBJECTIVE: Early diagnosis of PAH is clinically challenging. Patterns of diagnostic delay in Australian and New Zealand PAH populations have not been explored in large-scale studies. We aimed to evaluate the magnitude, risk factors and survival impact of diagnostic delay in Australian and New Zealand PAH patients. METHODS: A cohort study of PAH patients from the PHSANZ Registry diagnosed from 2004 to 2017 was performed. Diagnostic interval was the time from symptom onset to diagnostic right heart catheterization as recorded in the registry. Factors associated with diagnostic delay were analysed in a multivariate logistic regression model. Survival rates were compared across patients based on the time to diagnosis using Kaplan-Meier method and Cox regression. RESULTS: A total of 2044 patients were included in analysis. At diagnosis, median age was 58 years (IQR: 43-69), female-to-male ratio was 2.8:1 and majority of patients were in NYHA FC III-IV (82%). Median diagnostic interval was 1.2 years (IQR: 0.6-2.7). Age, CHD-PAH, obstructive sleep apnoea and peripheral vascular disease were independently associated with diagnostic interval of ≥1 year. No improvement in diagnostic interval was seen during the study period. Longer diagnostic interval was associated with decreased 5-year survival. CONCLUSION: PAH patients experience significant diagnostic interval, which has not improved despite increased community awareness. Age, cardiovascular and respiratory comorbidities are significantly associated with longer time to diagnosis. Mortality rates appear higher in patients who experience longer diagnostic interval.

The FaceBase Consortium: a comprehensive resource for craniofacial researchers.

The FaceBase Consortium, funded by the National Institute of Dental and Craniofacial Research, National Institutes of Health, is designed to accelerate understanding of craniofacial developmental biology by generating comprehensive data resources to empower the research community, exploring high-throughput technology, fostering new scientific collaborations among researchers and human/computer interactions, facilitating hypothesis-driven research and translating science into improved health care to benefit patients. The resources generated by the FaceBase projects include a number of dynamic imaging modalities, genome-wide association studies, software tools for analyzing human facial abnormalities, detailed phenotyping, anatomical and molecular atlases, global and specific gene expression patterns, and transcriptional profiling over the course of embryonic and postnatal development in animal models and humans. The integrated data visualization tools, faceted search infrastructure, and curation provided by the FaceBase Hub offer flexible and intuitive ways to interact with these multidisciplinary data. In parallel, the datasets also offer unique opportunities for new collaborations and training for researchers coming into the field of craniofacial studies. Here, we highlight the focus of each spoke project and the integration of datasets contributed by the spokes to facilitate craniofacial research.

Feasibility and Safety of a Transthoracic Pneumostoma Airway Bypass in Severe Emphysema Patients.

BACKGROUND: Emphysema is characterised by airflow obstruction, hyperinflation, and resultant dyspnoea. It is worth investigating whether decompression improves lung mechanics and enhances quality of life (QoL). OBJECTIVES: The purpose of this study was to describe the feasibility and safety of creating a transthoracic pneumostoma to enable lung reduction. METHODS: A transthoracic 10-mm diameter Portaero Access Tube (Portaero™, Cupertino, CA, USA) was implanted via a third intercostal space incision in 15 severe emphysema patients [mean age 63 years, forced expiratory volume in 1 s 54% predicted, diffusing capacity for carbon monoxide 31% predicted, residual volume 246% predicted, Six-Minute Walk Test 296 m]. Four weeks later, an 8-mm Portaero Disposable Tube (3-8 cm in length) was substituted and changed daily thereafter. The targeted primary endpoints were a ≥12% increase in forced expiratory volume in 1 s and a decrease of ≥4 points in Saint George's Respiratory Questionnaire score at 6 months. RESULTS: Sixteen procedures were performed on 15 patients, complicated by 1 intercostal haemorrhage, 1 pneumothorax, and universal mild surgical emphysema. Early patency issues were common, but often responded to external endoscopic debridement or argon plasma laser. Three-month patency was achieved in 9 of 15 patients, and 6 of these had long-term patency (mean of 4 years). Patency was associated with potentially useful long-term improvements or stability in spirometry, residual volume, and QoL. However, the primary endpoints were not met at 6 months. CONCLUSION: The creation and maintenance of a transthoracic pneumostoma appears feasible and safe in patients with severe emphysema. Further studies refining patient selection (perhaps via chest computed tomography collateral ventilation and fissure assessments), techniques, and tube materials are suggested.

Update on pharmacotherapy for pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is a rare disease with a poor prognosis if not treated. Pharmacological treatment options for PAH have increased significantly over the past 10 years, with availability of intravenous, oral and inhaled drugs targeting the nitric oxide, endothelin and prostacyclin pathways. Treatment with these therapies in specialised pulmonary hypertension centres has resulted in reductions in patient symptoms, disease progression and mortality, and improved exercise capacity. Recognition of chronic thromboembolic pulmonary hypertension is important, as this cause of pulmonary hypertension may be amenable to surgical treatment. Several new oral drugs, including macitentan, riociguat and selexipag, some of which have novel modes of action, and the use of combinations of PAH drugs have recently been shown to be beneficial in treating PAH and are likely to change treatment for this condition in the future.

MicroRNA-17-92, a direct Ap-2α transcriptional target, modulates T-box factor activity in orofacial clefting.

Among the most common human congenital anomalies, cleft lip and palate (CL/P) affects up to 1 in 700 live births. MicroRNA (miR)s are small, non-coding RNAs that repress gene expression post-transcriptionally. The miR-17-92 cluster encodes six miRs that have been implicated in human cancers and heart development. We discovered that miR-17-92 mutant embryos had severe craniofacial phenotypes, including incompletely penetrant CL/P and mandibular hypoplasia. Embryos that were compound mutant for miR-17-92 and the related miR-106b-25 cluster had completely penetrant CL/P. Expression of Tbx1 and Tbx3, the DiGeorge/velo-cardio-facial (DGS) and Ulnar-mammary syndrome (UMS) disease genes, was expanded in miR-17-92 mutant craniofacial structures. Both Tbx1 and Tbx3 had functional miR seed sequences that mediated gene repression. Analysis of miR-17-92 regulatory regions uncovered conserved and functional AP-2α recognition elements that directed miR-17-92 expression. Together, our data indicate that miR-17-92 modulates expression of critical T-box transcriptional regulators during midface development and is itself a target of Bmp-signaling and the craniofacial pioneer factor AP-2α. Our data are the first genetic evidence that an individual miR or miR cluster is functionally important in mammalian CL/P.

Iron deficiency in patients with idiopathic pulmonary arterial hypertension.

BACKGROUND: Iron deficiency has been reported to be highly prevalent in idiopathic pulmonary arterial hypertension (iPAH) patients, with the potential to influence cardiac performance, pulmonary artery pressures and the pulmonary vascular response to hypoxia. METHODS: Iron status was evaluated in 29 iPAH patients, and was related to haemodynamic, echocardiographic and exercise parameters. RESULTS: Iron deficiency was present in 44.8% of all iPAH patients, although anaemia was only present in 13.8%. Iron-deficient patients had similar exercise capacity (6MWD: 446±141 m), compared to iron-sufficient patients (421±193 m), however 46.2% of iron deficient patients had NYHA FC 3 or higher, compared to 12.5% in non-iron deficient group. Additionally iron-deficient patients showed increased mean pulmonary arterial pressure (63.3±12.2 mmHg; iron deficient vs. 38.8±16.7 mmHg; non-iron deficient) and reduced cardiac index (1.3±0.2 L/min/m(2); iron deficient vs. 2.5±0.4 L/min/m(2); non-iron deficient). CONCLUSIONS: Iron deficiency is highly prevalent in iPAH, and the extent of iron deficiency is related to haemodynamics and NYHA functional class. While the exact mechanism of iron deficiency is unknown, our study suggests that treatment of iron deficiency should be considered in iPAH patients.

Relationship between trough plasma and epithelial lining fluid concentrations of voriconazole in lung transplant recipients.

Trough (predose) voriconazole concentrations in plasma and pulmonary epithelial lining fluid (ELF) of lung transplant recipients receiving oral voriconazole preemptive treatment were determined. The mean (± standard deviation [SD]) ELF/plasma ratio was 12.5 ± 6.3. A strong positive linear relationship was noted between trough plasma and ELF voriconazole concentrations (r(2) = 0.87), suggesting the feasibility of using trough plasma voriconazole concentration as a surrogate to estimate the corresponding concentration in ELF of lung transplant recipients.

Predation affects body shape in the knife livebearer Alfaro cultratus (Cyprinodontiformes: Poeciliidae).

Livebearing fishes are a common model for studying the effects of predation on prey biology. Numerous studies have found differences in life history, sexual selection, behavior, and morphology between populations of the same species that co-occur with predators and those that do not. Alfaro cultratus is a livebearing fish with populations in different predation environments, but unlike other livebearers, this species also has an extreme body shape that is laterally compressed. Given this unusual morphology, we asked if predation environment would still predict overall body shape, as has been documented in other species. We collected specimens from both predator and no predator sites in Costa Rica and used a geometric morphometrics analysis to determine if body shape is affected by predation environment, while controlling for size and river gradient. Body shape does indeed differ between predation environments; however, the observed differences contrast with the patterns found in other livebearer systems. Alfaro cultratus in predation environments had deeper and shorter bodies and deeper caudal peduncles than those found in environments without dominant fish predators.

TFAP2 paralogs regulate midfacial development in part through a conserved ALX genetic pathway.

Cranial neural crest development is governed by positional gene regulatory networks (GRNs). Fine-tuning of the GRN components underly facial shape variation, yet how those in the midface are connected and activated remain poorly understood. Here, we show that concerted inactivation of Tfap2a and Tfap2b in the murine neural crest even during the late migratory phase results in a midfacial cleft and skeletal abnormalities. Bulk and single-cell RNA-seq profiling reveal that loss of both Tfap2 members dysregulated numerous midface GRN components involved in midface fusion, patterning, and differentiation. Notably, Alx1/3/4 (Alx) transcript levels are reduced, while ChIP-seq analyses suggest TFAP2 directly and positively regulates Alx gene expression. TFAP2 and ALX co-expression in midfacial neural crest cells of both mouse and zebrafish further implies conservation of this regulatory axis across vertebrates. Consistent with this notion, tfap2a mutant zebrafish present abnormal alx3 expression patterns, and the two genes display a genetic interaction in this species. Together, these data demonstrate a critical role for TFAP2 in regulating vertebrate midfacial development in part through ALX transcription factor gene expression.

Preoperative echocardiographic-defined moderate-severe pulmonary hypertension predicts prolonged duration of mechanical ventilation following lung transplantation for patients with COPD.

PURPOSE: Recent studies have suggested that pretransplant secondary pulmonary hypertension (PHT) may be associated with worse outcomes following lung transplantation. We sought to determine whether COPD patients with secondary PHT have inferior intensive care outcomes following lung transplantation. METHODS: This is a single-center, retrospective analysis of all lung transplant recipients between 2000 and 2009 for a primary diagnosis of COPD. Patients were stratified a priori into three pulmonary arterial pressure groups based on right ventricular systolic pressure (RVSP): no PHT (RVSP < 35 mmHg), mild PHT (35 ≤ RVSP < 45 mmHg), and moderate-severe PHT (RVSP ≥ 45 mmHg). Outcome measures were duration of mechanical ventilation, intensive care unit (ICU) length of stay, and PaO(2)/fraction inspired oxygen (PaO(2)/F(I)O(2)) ratio at 24 h posttransplantation. RESULTS: A total of 46 COPD lung transplant recipients with documented pretransplant RVSP were included in the analysis, including 18 with no PHT, 20 with mild PHT, and eight with moderate-severe PHT. There were no differences in baseline demographics between the three pulmonary arterial pressure groups. The presence of moderate-severe PHT predicted increased duration of mechanical ventilation (P = 0.024), worse PaO(2)/F(I)O(2) ratio at 24 h (P = 0.027), and a trend toward increased ICU length of stay (P = 0.055). RVSP was the strongest risk factor for duration of mechanical ventilation and ICU length of stay. There was no difference in 1-year survival amongst the three pulmonary arterial pressure groups. CONCLUSIONS: Preoperative moderate-severe PHT predicts prolonged duration of mechanical ventilation following lung transplantation in COPD subjects.

Long-term outcomes from bronchoscopic lung volume reduction using a bronchial prosthesis.

BACKGROUND AND OBJECTIVE: We evaluated long-term safety and lung function outcomes in a cohort of patients with severe upper-zone heterogeneous emphysema who underwent bronchoscopic lung volume reduction (BLVR) performed with the Emphasys one-way valve. METHODS: A retrospective cohort study was undertaken to assess long-term outcomes in 23 consecutive patients who underwent upper lobe BLVR between July 2001 and November 2003 as part of a first-in-humans study. Long-term follow up (>12 months) was available in 16/23 patients (median duration of follow up 64 months (range 15-90 months)). Both unilateral (n=4) and bilateral (n=12) BLVR procedures were performed with a mean of 6 (range 3-11) valves being inserted. Changes in pulmonary function tests were assessed longitudinally following the procedure. RESULTS: 13/16 and 11/16 patients showed post-procedure improvements in FEV1 and DL(CO) , respectively. However, early improvements in pulmonary function were not sustained with only 6/16 patients still showing improved lung function at the end of follow up. There were no significant improvements in other indices of pulmonary function. Three patients, in the absence of clinical benefit, proceeded to lung transplantation at 15, 16 and 44 months post BLVR. Four patients died during the course of the study at 27, 29, 39 and 50 months post procedure. CONCLUSIONS: BLVR with the Emphasys one-way valve has an acceptable safety profile and in select patients may achieve long-term sustained improvements in pulmonary function.

Ep400 deficiency in Schwann cells causes persistent expression of early developmental regulators and peripheral neuropathy.

Schwann cells ensure efficient nerve impulse conduction in the peripheral nervous system. Their development is accompanied by defined chromatin changes, including variant histone deposition and redistribution. To study the importance of variant histones for Schwann cell development, we altered their genomic distribution by conditionally deleting Ep400, the central subunit of the Tip60/Ep400 complex. Ep400 absence causes peripheral neuropathy in mice, characterized by terminal differentiation defects in myelinating and non-myelinating Schwann cells and immune cell activation. Variant histone H2A.Z is differently distributed throughout the genome and remains at promoters of Tfap2a, Pax3 and other transcriptional regulator genes with transient function at earlier developmental stages. Tfap2a deletion in Ep400-deficient Schwann cells causes a partial rescue arguing that continued expression of early regulators mediates the phenotypic defects. Our results show that proper genomic distribution of variant histones is essential for Schwann cell differentiation, and assign importance to Ep400-containing chromatin remodelers in the process.