Perovskite CoSn(OH)6 nanocubes with tuned d-band states towards enhanced oxygen evolution reactions

The CoSn(OH)6 perovskite hydroxide is a structure stable and inexpensive electrocatalyst for the oxygen evolution reaction (OER). However, the OER activity of CoSn(OH)6 is still unfavorable due to its limited active sites. In this work, an Fe3+ doping strategy is used to optimize the d-band state of the CoSn(OH)6 perovskite hydroxide. The CoSn(OH)6 catalyst with slightly Fe3+ doped nanocubes is synthesized by a facile hydrothermal method. Structure characterization shows that Fe3+ ions are incorporated into the crystal structure of CoSn(OH)6. Owing to the regulation of the electronic structure, CoSn(OH)6-Fe1.8% exhibits an OER overpotential of 289 mV at a current density of 10 mA cm-2 in OER electrochemical tests. In situ Raman spectroscopy shows that no obvious re-construction occurred during the OER for both CoSn(OH)6 and CoSn(OH)6-Fe1.8%. DFT calculations show that the introduction of Fe3+ into CoSn(OH)6 can shift the d-band center to a relatively high position, thus promoting the OER intermediates' adsorption ability. Further DFT calculations suggest that incorporation of an appropriate amount of Fe3+ into CoSn(OH)6 significantly reduces the rate-determining Gibbs free energy during the OER. This work offers valuable insights into tuning the d-band center of perovskite hydroxide materials for efficient OER applications.

Synonymous mutations in TLR2 and TLR9 genes decrease COPD susceptibility in the Chinese Han population

INTRODUCTION

Previous studies have found associations between polymorphisms in some candidate genes and chronic obstructive pulmonary disease (COPD) risk. However, the association between TLR2 and TLR9 polymorphisms and COPD risk remains uncertain.

METHODS

Four variants (rs352140, rs3804099, rs3804100, and rs5743705) of the TLR2 and TLR9 genes in 540 COPD patients and 507 healthy controls were genotyped using the Agena MassARRAY system. Odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the association of TLR2 and TLR9 polymorphisms with COPD risk by logistic regression analysis.

RESULTS

TLR9-rs352140, TLR2-rs3804100, and TLR2-rs5743705 were related to a lower risk of COPD among Chinese people and the significance still existed after Bonferroni correction. Additionally, rs3804099, rs3804100, and rs352140 were found to be associated with COPD development in different subgroups (males, age ≤ 68 years, smokers, BMI < 24 kg/m2, and acute exacerbation).

CONCLUSIONS

Our findings indicated that TLR9 and TLR2 polymorphisms had protective effects on the development of COPD among Chinese people.

Linking New Alleles at the Oscillator Loci to Flowering and Expansion of Asian Rice

The central oscillator is believed to be the key mechanism by which plants adapt to new environments. However, impacts from hybridization, the natural environment, and human selection have rarely been assessed on the oscillator of a crop. Here, from clearly identified alleles at oscillator loci (OsCCA1/LHY, OsPRR95, OsPRR37, OsPRR59, and OsPRR1) in ten diverse genomes of Oryza sativa, additional accessions, and functional analysis, we show that rice's oscillator was rebuilt primarily by new alleles from recombining parental sequences and subsequent 5' or/and coding mutations. New alleles may exhibit altered transcript levels from that of a parental allele and are transcribed variably among genetic backgrounds and natural environments in RIL lines. Plants carrying more expressed OsCCA1_a and less transcribed OsPRR1_e flower early in the paddy field. 5' mutations are instrumental in varied transcription, as shown by EMSA tests on one deletion at the 5' region of highly transcribed OsPRR1_a. Compared to relatively balanced mutations at oscillator loci of Arabidopsis thaliana, 5' mutations of OsPRR37 (and OsCCA1 to a less degree) were under negative selection while those of OsPRR1 alleles were under strong positive selection. Together, range expansion of Asian rice can be elucidated by human selection on OsPRR1 alleles via local flowering time-yield relationships.

A study on etiology of incontinence in double knockout mouse model

INTRODUCTION AND OBJECTIVE

Stress urinary incontinence is of concern in both pediatric and adult population. Double mutant GLI family zinc finger Gli2^+/-; Gli3^Δ699/+ murine model of stress incontinence has been recently developed as a reliable model which does not require surgical manipulation to create incontinence and is shown to survive to adulthood. The aim of this study was to establish the etiology of incontinence in the double mutant Gli2^+/-; Gli3^Δ699/+ mice.

STUDY DESIGN

We used 13 cluster of differentiation 1 (CD-1) mice (7-9 weeks) for demonstration of histology of the bladder and urethra. There were 3 Wild Gli2^+/- females, 2 Wild Gli2^+/- males, 4 Gli2^+/-;Gli3^Δ699/+ females and 4 Gli2^+/-;Gli3^Δ699/+ males. The Wild Gli2^+/- mice served as the control group and Gli2^+/-;Gli3^Δ699/+ mice served as the test group. Additionally, eight 16.5 days mice (2 each of Wild Gli2^+/- females, Wild Gli2^+/- males, double knockout (DKO) Gli2^+/-;Gli3^Δ699/+ females and Gli2^+/-;Gli3^Δ699/+ males) were used to assess the histology of the spinal cord. The gross appearance of bladder and urethra was studied using ink injection assays. Immunohistochemistry was done for smooth muscle actin and cytokeratin.

RESULTS

Gross and histologic appearance confirmed the previously reported widening of bladder outlet and hypoplasia of smooth muscles in female urethra and also established them in the male urethra of Gli2^+/-;Gli3^Δ699/+ mice compared to Gli2^+/- mice. The double knockout mice were smaller than the Gli2 mice (5.2 vs 6.1 cm, p = 0.002). Immunohistochemistry demonstrated epithelial hyperplasia and smooth muscle hypoplasia. Additionally, there was prostatic hypoplasia in the Gli2^+/-;Gli3^Δ699/+ male mice. The spinal cord length for body size appeared comparable between the Gli2^+/- and Gli2^+/-;Gli3^Δ699/+ mice but histological evaluation revealed abnormal development of the caudal end of the vertebral body with premature termination of the spinal cord (Figure).

DISCUSSION

The histological changes in the bladder neck and urethra were consistent to those previously reported. While previous report described the findings in female mice only, we confirmed that these findings are also present in males as well as prostatic hypoplasia, a possible additional factor leading to stress incontinence. The most important finding in the present study however, was the detection of premature termination of spinal cord in the DKO Gli2^+/-; Gli3^Δ699/+ mice which has not been reported previously and is likely a major contributor to incontinence in this model.

CONCLUSION

The incontinence in male as well as female Gli2^+/-; Gli3^Δ699/+ mice is due to both myogenic and neurogenic involvement. These double knockout mice are a valuable model of stress incontinence related to neurogenic bladder due to low outlet resistance.

Passenger comfort evaluation of the stowing and unloading luggage task in high-speed trains: Fusion of R-DEMATEL and FNN

At present, high-speed trains have become popular modern transportation. As a significant part of the high-speed train riding activity, the stowing and unloading luggage task has its characteristics. To comprehensively and reasonably evaluate passenger comfort of the stowing and unloading luggage task in high-speed trains. In this paper, passenger behavior characteristics are firstly analyzed by the author, the theoretical architecture of passenger comfort evaluation is constructed with the perspective of product aesthetics and ergonomics, and then the process of the passenger comfort evaluation is put forward. Secondly, a combination of Rough Number (RN) and Decision Making Trial and Evaluation Laboratory (DEMATEL) (i.e. R-DEMATEL) is utilized to solve the centrality degree of comfort influencing factors and determine comfort evaluation indexes. Furthermore, the passenger comfort evaluation model with Fuzzy Neural Network (FNN) is constructed and trained. After that, the sample data of the evaluation are collected through the simulated experiment of the stowing and unloading luggage task, and they are trained with FNN comparing to Back Propagation Neural Network (BPNN). Eventually, the result of examples testing is verified that the effectiveness of the proposed method.

Ectopic expression of Irx3 and Irx5 in the paraventricular nucleus of the hypothalamus contributes to defects in Sim1 haploinsufficiency

The paraventricular nucleus of the hypothalamus (PVH) contains a heterogeneous cluster of Sim1-expressing neurons critical for feeding regulation. Sim1 haploinsufficiency results in hyperphagic obesity with disruption of PVH neurons, yet the molecular profiles of PVH neurons and the mechanism underlying the defects of Sim1 haploinsufficiency are not well understood. By single-cell RNA sequencing, we identified two major populations of Sim1⁺ PVH neurons, which are differentially affected by Sim1 haploinsufficiency. The Iroquois homeobox genes Irx3 and Irx5 have been implicated in the hypothalamic control of energy homeostasis. We found that Irx3 and Irx5 are ectopically expressed in the Sim1⁺ PVH cells of Sim1^+/− mice. By reducing their dosage and PVH-specific deletion of Irx3, we demonstrate that misexpression of Irx3 and Irx5 contributes to the defects of Sim1^+/− mice. Our results illustrate abnormal hypothalamic activities of Irx3 and Irx5 as a central mechanism disrupting PVH development and feeding regulation in Sim1 haploinsufficiency.

Impact of rate control medications on one-year outcomes with atrial fibrillation and heart failure

Purpose

Atrial fibrillation (AF) and heart failure (HF) often coexist. The impact of rate-control regimens in AF and HF patients has not been well understood.

Methods

In this multicenter, prospective registry with one-year follow-up, 1359 persistent or permanent AF patients got enrolled. A 1:1 HF to non-HF propensity score matching was applied to adjust for confounding variables. The primary endpoint was all-cause mortality while the secondary endpoint was defined as cardiovascular death and stroke. Multivariate Cox analysis was performed to evaluate the association between different rate-control treatment and incidence of adverse events.

Results

Before matching, HF patients were much younger and more likely to be female. They had a much higher prevalence of previous myocardial infarction, chronic obstructive pulmonary disease and valvular heart disease. Among 1359 participants, we identified 1016 matched patients. The number of drugs did not affect the risk of all-cause mortality in both cohorts. For non-HF patients, using calcium channel blockers (CCBs) plus digoxin had a significant higher risk of all-cause death (HR=5.703, 95% CI 1.334–24.604, p=0.019) and cardiovascular death (HR=9.558, 95% CI 2.127–42.935, p=0.003) compared with patients not receiving rate-control treatment. The use of beta-blockers, CCBs, digoxin alone, other dual or triple combinations was not related to risk of adverse events in both groups.

Conclusions

The combined use of CCBs and digoxin was related to increase all-cause and cardiovascular mortality in AF patients without HF but not for those with HF. However, the ideal rate-control regimen for AF and HF patients has not been established and well-designed clinical trials are needed.

Funding Acknowledgement

Type of funding sources: None. Results of multivariate Cox analysisKaplan-Meier curves by drug numbers

Enhanced Photoelectrochemical Water Oxidation Performance in Bilayer TiO2 /α-Fe2 O3 Nanorod Arrays Photoanode with Cu : NiOx as Hole Transport Layer and Co-Pi as Cocatalyst

Efficient charge transfer and excellent surface water oxidation kinetics are key factors in determining the photoelectrochemical (PEC) water splitting performance in photoelectrodes. Herein, a bilayer TiO₂ /α-Fe₂ O₃ nanorod (NR) arrays photoanode was prepared with deposited Cu-doped NiO_x (Cu : NiO_x ) hole transport layer (HTL) and Co-Pi oxygen evolution reaction (OER) cocatalyst for PEC water oxidation. The hierarchical TiO₂ /α-Fe₂ O₃ composite obtained by a secondary hydrothermal process exhibited an inapparent bilayer structure by embedding the underlayer TiO₂ NR arrays at the bottom part of the post-grown α-Fe₂ O₃ NR arrays. The underlayer TiO₂ NRs acted as an effective shuttling pathway for transferring photoelectrons generated in the upper hematite light absorber layer. A p-type inter-Cu : NiO_x HTL was introduced to form a build-in p-n electric field between Cu : NiO_x and α-Fe₂ O₃ NRs, which improved the hole extraction from α-Fe₂ O₃ to Co-Pi OER catalyst. As expected, the as-engineered TiO₂ /α-Fe₂ O₃ /Cu : NiO_x /Co-Pi photoanode displayed an excellent photocurrent density of 2.43 mA cm^-2 at 1.23 V versus the reversible hydrogen electrode (V_RHE ), up to 4.05 and 2.23 times greater than those of the bare α-Fe₂ O₃ (0.60 mA cm^-2 ) and TiO₂ /α-Fe₂ O₃ , respectively. The results demonstrate that the bottom-up engineering of electron-hole transport channels and cocatalyst modification is an attractive maneuver to enhance the PEC water oxidation activity in hematite and other photoanodes.

[Clinical and genetic studies on 76 patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria]

Objective: To analyze the clinical features, genetic characteristics, treatment and follow-up results of patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria, and to discuss the optimal strategies for assessing and treating such patients. Methods: From January 1998 to December 2020, 76 patients with hydrocephalus due to methylmalonic acidemia combined with homocysteinuria in the Department of Pediatrics in 11 hospitals including Peking University First Hospital were diagnosed by biochemical, genetic analysis and brain imaging examination. The patients were divided into operation-group and non-operation-group according to whether they underwent ventriculoperitoneal shunt. The clinical features, laboratory examinations, genotype, and follow-up data were retrospectively analyzed. Data were compared between the two groups using rank sum test, and categorical data were compared using χ² test. Results: Among the 76 patients (51 male, 25 female), 5 were detected by newborn screening, while 71 were diagnosed after clinical onset, 68 cases (96%) had early-onset, 3 cases (4%) had late-onset. The most common clinical manifestations of 74 cases with complete data were psychomotor retardation in 74 cases (100%), visual impairment in 74 cases (100%), epilepsy in 44 cases (59%), anemia in 31 cases (42%), hypotonia or hypertonia in 21 cases (28%), feeding difficulties in 19 cases (26%) and disturbance of consciousness in 17 cases (23%). Genetic analysis was performed in 76 cases, all of whom had MMACHC gene variations, including 30 homozygous variations of MMACHC c.609G>A. The most common variations were c.609G>A (94, 62.7%), followed by c.658_660del (18, 12.0%), c.567dupT (9, 6.0%) and c.217C>T (8, 5.3%). Therapy including cobalamin intramuscular injection, L-carnitine and betaine were initiated immediately after diagnosis. A ventriculoperitoneal shunt operation was performed in 41 cases (operation group), and 31 patients improved after metabolic intervention (non-operation group). There was no significant difference in the age of onset, the age of diagnosis, the blood total homocysteine, methionine, and urinary methylmalonic acid concentration between the two groups (all P>0.05). The symptoms of psychomotor development, epilepsy, and visual impairments improved gradually after a long-term follow-up in the operation group. Conclusions: Hydrocephalus is a severe complication of methylmalonic acidemia combined with homocysteinuria. The most common clinical manifestations are psychomotor retardation, visual impairment, and epilepsy. It usually occurs in early-onset patients. Early diagnosis and etiological treatment are very important. Hydrocephalus may improve after metabolic intervention in some patients. For patients with severe ventricular dilatation, prompt surgical intervention can improve the prognosis.

Irx3 and Irx5 in Ins2-Cre+ cells regulate hypothalamic postnatal neurogenesis and leptin response

Obesity is mainly due to excessive food intake. IRX3 and IRX5 have been suggested as determinants of obesity in connection with the intronic variants of FTO, but how these genes contribute to obesity via changes in food intake remains unclear. Here, we show that mice doubly heterozygous for Irx3 and Irx5 mutations exhibit lower food intake with enhanced hypothalamic leptin response. By lineage tracing and single-cell RNA sequencing using the Ins2-Cre system, we identify a previously unreported radial glia-like neural stem cell population with high Irx3 and Irx5 expression in early postnatal hypothalamus and demonstrate that reduced dosage of Irx3 and Irx5 promotes neurogenesis in postnatal hypothalamus leading to elevated numbers of leptin-sensing arcuate neurons. Furthermore, we find that mice with deletion of Irx3 in these cells also exhibit a similar food intake and hypothalamic phenotype. Our results illustrate that Irx3 and Irx5 play a regulatory role in hypothalamic postnatal neurogenesis and leptin response.

Feasibility of a home-based telerehabilitation exercise program for heart failure patients – a prospective randomized controlled trial

Background

Chronic heart failure (CHF) is a prevalent disease, and CHF patients are recommended to participate in cardiac rehabilitation programs. Due to frailty and rural living, many CHF patients refuse to do so. To meet these challenges, there is need of a more convenient and efficient rehabilitation system. A home-based telerehabilitation program was designed to enable CHF patients to exercise via video-conferencing in their homes, allowing two-way communication with their therapist, and for patients to exercise together.

Purpose

We aimed to evaluate the feasibility of a home-based telerehabilitation exercise program designed for CHF patients.

Methods

67 subjects were included in a two-arm prospective randomized controlled trial if they had stable CHF, were on optimal medical therapy, and refused to participate in standard outpatient rehabilitation. All subjects participated in a 2-day “Living with heart failure” course. The intervention group (n=30) was educated in the use of a tablet computer, a video-conferencing app, and an app with exercise videos, before they received home-based telerehabilitation exercise twice a week for 3 months. Each exercise session consisted of 20 min warm-up, followed by 4x4 min high intensity intervals with 3 min active breaks, and 15 min calm down. Outcomes, measured at baseline and 3 months, included the 6-minute walk test, the Minnesota living with heart failure Questionnaire (MLHFQ), adherence, adverse events, satisfaction, and patient reported measures of safety, technical aspects, and motivational factors.

Results

Mean age was 68 (65.6–71.1) years (82% male). By the 6-minute walk test, the exercise group increased their walking distance with 18 m from baseline 451 m, p=0.07. No change (+0.8 m) was seen in the control group from baseline (478 m) to 3 months, but no significant difference between groups (p=0.20). We found a significant decrease in MLHFQ score for the exercise group (baseline 42.6, change −13.8, p=0.003), and for the control group (baseline 41.2, change −12.6, p=0.002), with no difference between groups (p=0.83). ≥80% fulfilled 80% of 24 exercises. One drop-out was registered, and no adverse events were reported during exercise. In total 96% (26/27) reported that they felt safe during home-based exercise via videoconferencing and 96% (24/25) reported that the intervention gave motivation to continue exercising on their own. Some minor technical issues with the videoconference software was present in 58% (15/26).

Conclusion

Home-based exercise training supported by real-time supervision by telemedicine was feasible, with high adherence and high level of patients' satisfaction. Telerehabilitation increased 6-minute walking distance and quality of life in CHF patients, but the changes were not statistically significant compared to controls. Despite some technical issues with the software and equipment used, the participants reported high motivation to further exercise.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Central Norway Regional Health Authority

The effects of the seat cushion contour and the sitting posture on surface pressure distribution and comfort during seated work

OBJECTIVES

The purpose of this paper is to investigate the effects of the seat cushion contour and the sitting posture on the seat pan interface pressure distribution and subjective comfort perception.

MATERIAL AND METHODS

Overall, 16 volunteers typed a text passage on a laptop while seated, by assuming 3 kinds of common sitting postures (forward, relaxed and upright) in 4 seat cushion configurations: chair only, and chair with 1 of 3 supplementary cushions. Pressure data and cushion comfort ratings were collected in the experiment.

RESULTS

It was found that the sitting posture and the seat cushion contour had different impacts on surface pressure. The seat cushion contour had an impact on pressure parameters and pressure distribution on the seat pan, while the sitting posture affected the location of peak pressure on the seat pan. The correlation analysis revealed that the subjective comfort rating was significantly correlated with average pressure (AP) and mean peak pressure (MPP).

CONCLUSIONS

The conclusion was that the cushion contour had a greater effect on seat pan interface pressure parameters than the sitting posture. Notably, AP and MPP can be indicators for assessing seat cushion comfort in a short-term perspective. Int J Occup Med Environ Health. 2020;33(5):675-89.

[Prognostic value of Montreal Cognitive Assessment in heart failure patients]

Objective: To explore the occurrence of cognitive impairment in Chinese heart failure (HF) patients and it's impact on prognosis. Methods: In this prospective observational study, a total of 990 HF patients were enrolled from 24 hospitals in China during December 2012 to November 2014. All patients were administrated with the interview-format Montreal Cognitive Assessment (MoCA), according to which they were divided into MoCA<26 (with cognitive impairment) group and MoCA≥26 (without cognitive impairment) group. Baseline data were collected and a 1-year follow up was carried out. Univariate and multivariate logistic or Cox regression were performed for 1-year outcomes. Results: Cognitive impairment was evidenced in 628 patients (63.4%) and they were more likely to be older, female, and with higher proportion of New York Heart Association(NYHA) class Ⅲ-Ⅳ, chronic obstructive pulmonary disease (COPD), ischemic heart disease, while body mass index (BMI), education level, and medical insurance rate were lower (all P<0.05) as compared to patients in MoCA≥26 group. The rate of percutaneous intervention, device implantation, cardiac surgery and evidence-based medications were significantly lower in MoCA<26 group than in MoCA≥26 group (all P<0.05). During the 1-year follow up, patients in the MoCA<26 group had higher all-cause mortality (10.2%(64/628) vs. 2.2%(8/362), P<0.01), cardiovascular mortality (5.9%(37/628) vs. 0.8%(3/362), P<0.01) and major adverse cardiac and cerebrovascular events (MACCE) (9.6%(60/628) vs. 2.5%(8/362), P<0.01) than patients in the MoCA≥26 group. In univariate regression, MoCA<26 was associated with increased all-cause mortality (HR(95%CI):4.739(2.272-9.885), P<0.01), cardiovascular mortality (HR(95%CI):7.258(2.237-23.548), P=0.001) and MACCE (OR(95%CI):4.143(2.031-8.453), P<0.01). After adjustment by multivariate regression, MoCA<26 was indicated as an independent risk factor for all-cause mortality (HR(95%CI): 6.387(2.533-16.104), P<0.01), cardiovascular mortality (HR(95%CI): 10.848(2.586-45.506), P=0.001) and MACCE (OR(95%CI): 4.081(1.299-12.816), P=0.016), while not for re-hospitalization for HF (OR(95%CI):1.010(0.700-1.457), P=0.957). Conclusions: Cognitive impairment is common in HF patients,and it is an independent prognostic factor for 1-year outcomes. Routine cognitive function assessment and active intervention are thus recommended for HF patients.

Hospital and healthcare insurance system record-based epidemiological study of myasthenia gravis in southern and northern China

OBJECTIVE

This is the first cross-region epidemiological study of myasthenia gravis (MG) in China. We estimated the incidence, prevalence, and medical costs of MG in southern China and explored the differences between the southern and northern Chinese populations.

METHODS

We collected and analyzed records from 20 hospitals in the southern city, Guangzhou, 13 hospitals in the northern city, Harbin, and two healthcare insurance systems: job based and residence based in Guangzhou during 2000-2017.

RESULTS

(1) The estimated annual incidence of MG was 1.55-3.66 per 100,000, and the estimated prevalence of MG was 2.19-11.07 per 100,000 in southern China based on insurance records. (2) The proportion of hospitalized MG patients in the south-based hospital records was three times as high as that in the north-based hospital records. (3) Female MG prevalence was significantly higher than male MG prevalence in Guangzhou, while the similar gender difference in Harbin was not statistically significant due to higher variation in earlier years. (4) The average expense was $35-42 for each outpatient service and $2526-2673 for each hospitalization expense in the south. (5) Contrary to the increase of insurance-based estimate of MG prevalence, the proportion of hospitalized MG patients did not increase over the years, suggesting rising awareness and utilization of health insurance.

CONCLUSIONS

The southern MG population had a significantly higher prevalence and a lower response threshold to medication than the northern MG population. These results are calling for further investigations on the genetic, cultural, and environmental variations of the Chinese MG populations between north and south.

Dual Regulatory Functions of SUFU and Targetome of GLI2 in SHH Subgroup Medulloblastoma

SUFU alterations are common in human Sonic Hedgehog (SHH) subgroup medulloblastoma (MB). However, its tumorigenic mechanisms have remained elusive. Here, we report that loss of Sufu alone is unable to induce MB formation in mice, due to insufficient Gli2 activation. Simultaneous loss of Spop, an E3 ubiquitin ligase targeting Gli2, restores robust Gli2 activation and induces rapid MB formation in Sufu knockout background. We also demonstrated a tumor-promoting role of Sufu in Smo-activated MB (∼60% of human SHH MB) by maintaining robust Gli activity. Having established Gli2 activation as a key driver of SHH MB, we report a comprehensive analysis of its targetome. Furthermore, we identified Atoh1 as a target and molecular accomplice of Gli2 that activates core SHH MB signature genes in a synergistic manner. Overall, our work establishes the dual role of SUFU in SHH MB and provides mechanistic insights into transcriptional regulation underlying Gli2-mediated SHH MB tumorigenesis.

Change and Maintenance Method for 3D Machining Procedure Model Based on Design Structure Matrix

A change and maintenance method is proposed based on the change propagation model and the procedure model information for solving data maintenance problem of 3D machining procedure model change and to help improve the flexibility of 3D machining procedure model and the reliability of the change result. Design Structure Matrix (DSM) is established by analyzing the relationships between machining features in the machining process route to obtain all possible propagation paths. On the basis of obtained paths, machining features that may be affected and machining procedure models related to machining features are stored by the structured method. Algorithms to solve the problems of adding, deleting and modifying machining features are proposed to realize the change and maintenance of 3D machining procedure model by combining machining procedure model’s information in the machining process route. In the end, some numerical examples are given to explain both rationality and feasibility of the proposed approaches.

Assessment of serum Golgi protein 73 as a biomarker for the diagnosis of significant fibrosis in patients with chronic HBV infection

Transient elastography (TE) is accurate in staging fibrosis noninvasively. However, a reliable serum biomarker with comparable accuracy is also important, especially when TE is unreliable/unavailable. Therefore, we aimed to evaluate the diagnostic performance of serum Golgi protein 73 (GP73) for significant fibrosis in patients with chronic HBV infection. A total of 801 patients with chronic liver disease (CLD; 492 chronic HBV infection and 309 non-HBV liver disease) with liver biopsy performance were enrolled. Healthy controls (n = 180) and hepatocellular carcinoma (HCC) patients (n = 85) were included for comparisons. Liver biopsy was used as the reference method for fibrosis staging. Serum GP73 level was measured in duplicate in double-blind fashion. Serum GP73 was highest in HCC but also significantly higher in chronic hepatitis B than in healthy controls. The elevation of serum GP73 in non-HCC patients was significantly associated with the presence of significant fibrosis independently of ALT level, liver stiffness (LS) value, inflammation grade and other confounding factors. The diagnostic performance of serum GP73 was accurate in antiviral-naïve HBV patients (area under the receiver operating curve [AUROC], 0.76 95% CI: 0.72-0.81) but not in patients with ongoing antiviral treatment (AUROC, 0.60). The utility of serum GP73 was also confirmed in non-HBV CLD (AUROC, 0.80 95% CI: 0.75-0.85). Serum GP73 was comparable to LS (AUROC, 0.78 95% CI: 0.73-0.82) and significantly better than AST to platelet ratio index (APRI) (AUROC, 0.67 95% CI: 0.62-0.72) and FIB-4 (AUROC, 0.68 95% CI: 0.63-0.73). In conclusion, serum GP73 is an accurate serum marker for significant fibrosis in chronic HBV infection, with higher accuracy than APRI and FIB-4. Serum GP73 is potentially a complementary tool for TE when evaluating the necessity of antiviral treatment, particularly in patients without definite antiviral indication.

A genetic female mouse model with congenital genitourinary anomalies and adult stages of urinary incontinence

AIMS

To characterize the urinary incontinence observed in adult Gli2^+/- ; Gli3^Δ699/+ female mice and identify the defects underlying the condition.

METHODS

Gli2^+/- and Gli3^Δ699/+ mice were crossed to generate: wild-type, mutant Gli2 (Gli2^+/- ), mutant Gli3 (Gli3^Δ699/+ ), and double mutant (Gli2^+/- ; Gli3^Δ699/+ ) female mice, verified via Polymerase Chain Reactions. Bladder functional studies including cystometrogram (CMG), leak point pressure (LPP), and voiding testing were performed on adult female mice. Female bladders and urethras were also analyzed via ink injection and histological assays.

RESULTS

CMG tracing showed no signal corresponding to the filling of the Gli2^+/- ; Gli3^Δ699/+ bladders. LPP were significantly reduced in Gli2^+/- ; Gli3^Δ699/+ mice compared to wild-type mice. CMG studies revealed a decrease in peak micturition pressure values in Gli2^+/- ; Gli3^Δ699/+ mice compared with all other groups. No significant differences between mutant and wild-type mice were detected in urinary output. Histological analyses revealed Gli2^+/- ; Gli3^Δ699/+ mice exhibited a widened urethra and a decrease in smooth muscle layer thickness in the bladder outlet and urethra, with increased mucosal folding.

CONCLUSIONS

Gli2^+/- ; Gli3^Δ699/+ adult female mice display persistent urinary incontinence due to the malformation of the bladder outlet and urethra. This presents a consistent and reliable genetic mouse model for female urinary incontinence and alludes to the key role of genetic factors involved in the condition.

Adult Gli2+/-;Gli3Δ699/+ Male and Female Mice Display a Spectrum of Genital Malformation

Disorders of sexual development (DSD) encompass a broad spectrum of urogenital malformations and are amongst the most common congenital birth defects. Although key genetic factors such as the hedgehog (Hh) family have been identified, a unifying postnatally viable model displaying the spectrum of male and female urogenital malformations has not yet been reported. Since human cases are diagnosed and treated at various stages postnatally, equivalent mouse models enabling analysis at similar stages are of significant interest. Additionally, all non-Hh based genetic models investigating DSD display normal females, leaving female urogenital development largely unknown. Here, we generated compound mutant mice, Gli2^+/–;Gli3^Δ699/+, which exhibit a spectrum of urogenital malformations in both males and females upon birth, and also carried them well into adulthood. Analysis of embryonic day (E)18.5 and adult mice revealed shortened anogenital distance (AGD), open ventral urethral groove, incomplete fusion of scrotal sac, abnormal penile size and structure, and incomplete testicular descent with hypoplasia in male mice, whereas female mutant mice displayed reduced AGD, urinary incontinence, and a number of uterine anomalies such as vaginal duplication. Male and female fertility was also investigated via breeding cages, and it was identified that male mice were infertile while females were unable to deliver despite becoming impregnated. We propose that Gli2^+/–;Gli3^Δ699/+ mice can serve as a genetic mouse model for common DSD such as cryptorchidism, hypospadias, and incomplete fusion of the scrotal sac in males, and a spectrum of uterine and vaginal abnormalities along with urinary incontinence in females, which could prove essential in revealing new insights into their equivalent diseases in humans.

Flexible calibration of phase-to-height conversion in fringe projection profilometry

A flexible new technique is presented to calibrate the monocular system of phase-based fringe projection profilometry, which is made of a camera, a projector, and a computer. The proposed algorithm mainly consists of a more flexible phase-to-height conversion model and a minimum norm solution, followed by a nonlinear optimization based on the maximum likelihood criterion. In the whole calibration procedure, this method only requires the camera to capture a few two-dimensional checkerboard target images and several deformed fringe images with at least three different orientations. The proposed technique neither subjects to certain limitations nor measures additional geometry parameters in advance. Also, no highly precise gauge blocks or extra reference phases are involved. In contrast with the existing methods, the proposed technique is easier to use and more flexible. Experiments have been performed to validate the performance of this technique.

Invalid phase values removal method for absolute phase recovery

A novel approach is presented for more effectively removing invalid phase values in absolute phase recovery. The approach is based on a detailed study involving the types and cases of invalid phase values. Meanwhile, some commonalities of the existing removal algorithms also are thoroughly analyzed. It is well known that rough absolute phase and fringe order maps can very easily be obtained by temporal phase unwrapping techniques. After carefully analyzing the components and fringe order distribution of the rough fringe order map, the proposed method chiefly adopts an entirely new strategy to refine a pure fringe order map. The strategy consists of three parts: (1) the square of an image gradient, (2) subregion areas of the binary image, and (3) image decomposition and composition. In combination with the pure fringe order map and a removal criterion, the invalid phase values can be identified and filtered out from the rough absolute phase map. This new strategy not only gets rid of the limitations of traditional removal methods but also has a two-fold function. The paper also offers different metrics from the experiment to evaluate the quality of the final absolute phase. In contrast with other removal methods, experimental results have verified the feasibility, effectiveness, and superiority of the proposed method.

Cobalt phosphate modified TiO2 nanowire arrays as co-catalysts for solar water splitting

Cobalt phosphate (Co-Pi) is photo-electrodeposited on TiO2 nanowire arrays in Co(2+) containing phosphate buffer. The resulting composite photoanode shows a generally enhanced photocurrent near the flat band potential region, and represents a 2.3 times improved photoconversion efficiency compared to that of pristine TiO2 in a neutral electrolyte. A negative effect on the photocurrent generation is also observed when loading TiO2 with a relatively thick Co-Pi layer, which is demonstrated to be due to the poor photohole transfer kinetics in the Co-Pi layer. Moreover, we find that Co-Pi can facilitate the photoelectrochemical performance of TiO2 over a wide pH range from 1-14. This improved activity is studied in detail by optical and electrochemical analyses. It is suggested that the mechanism of the overpotential-demanding water oxidation reaction is changed to a facile pathway by the Co-based electrocatalyst. At the same time, the more significant band bending is induced by the Co-Pi catalyst decreasing the charge recombination. This work provides a feasible route to reduce the external power needed to drive water splitting by coupling an electrocatalyst with a photocatalyst, as well as mechanistic insights important for other Co-Pi modified photoelectrodes for solar-driven water splitting.

T396I mutation of mouse Sufu reduces the stability and activity of Gli3 repressor

Hedgehog signaling is primarily transduced by two transcription factors: Gli2, which mainly acts as a full-length activator, and Gli3, which tends to be proteolytically processed from a full-length form (Gli3^FL) to an N-terminal repressor (Gli3^REP). Recent studies using a Sufu knockout mouse have indicated that Sufu is involved in regulating Gli2 and Gli3 activator and repressor activity at multiple steps of the signaling cascade; however, the mechanism of specific Gli2 and Gli3 regulation remains to be elucidated. In this study, we established an allelic series of ENU-induced mouse strains. Analysis of one of the missense alleles, Sufu^T396I, showed that Thr³⁹⁶ residue of Sufu played a key role in regulation of Gli3 activity. Sufu^T396I/T396I embryos exhibited severe polydactyly, which is indicative of compromised Gli3 activity. Concomitantly, significant quantitative reductions of unprocessed Gli3 (Gli3^FL) and processed Gli3 (Gli3^REP) were observed in vivo as well as in vitro. Genetic experiments showed that patterning defects in the limb buds of Sufu^T396I/T396I were rescued by a constitutive Gli3^REP allele (Gli3^∆699), strongly suggesting that Sufu^T396I reduced the truncated Gli3 repressor. In contrast, Sufu^T396I qualitatively exhibited no mutational effects on Gli2 regulation. Taken together, the results of this study show that the Thr³⁹⁶ residue of Sufu is specifically required for regulation of Gli3 but not Gli2. This implies a novel Sufu-mediated mechanism in which Gli2 activator and Gli3 repressor are differentially regulated.

TiO2/Bi2S3 core–shell nanowire arrays for photoelectrochemical hydrogen generation

This paper demonstrates the procedure for construction of nontoxic TiO₂/Bi₂S₃ core–shell NWA photoanodes for PEC hydrogen generation.

Formation of proximal and anterior limb skeleton requires early function of Irx3 and Irx5 and is negatively regulated by Shh signaling

Limb skeletal pattern relies heavily on graded Sonic hedgehog (Shh) signaling. As a morphogen and growth cue, Shh regulates identities of posterior limb elements, including the ulna/fibula and digits 2 through 5. In contrast, proximal and anterior structures, including the humerus/femur, radius/tibia, and digit 1, are regarded as Shh independent, and mechanisms governing their specification are unclear. Here, we show that patterning of the proximal and anterior limb skeleton involves two phases. Irx3 and Irx5 (Irx3/5) are essential in the initiating limb bud to specify progenitors of the femur, tibia, and digit 1. However, these skeletal elements can be restored in Irx3/5 null mice when Shh signaling is diminished, indicating that Shh negatively regulates their formation after initiation. Our data provide genetic evidence supporting the concept of early specification and progressive determination of anterior limb pattern.

A switch from low to high Shh activity regulates establishment of limb progenitors and signaling centers

The patterning and growth of the embryonic vertebrate limb is dependent on Sonic hedgehog (Shh), a morphogen that regulates the activity of Gli transcription factors. However, Shh expression is not observed during the first 12 hr of limb development. During this phase, the limb bud is prepatterned into anterior and posterior regions through the antagonistic actions of transcription factors Gli3 and Hand2. We demonstrate that precocious activation of Shh signaling during this early phase interferes with the Gli3-dependent specification of anterior progenitors, disturbing establishment of signaling centers and normal outgrowth of the limb. Our findings illustrate that limb development requires a sweet spot in the level and timing of pathway activation that allows for the Shh-dependent expansion of posterior progenitors without interfering with early prepatterning functions of Gli3/Gli3R or specification of anterior progenitors.

Antagonistic and cooperative actions of Kif7 and Sufu define graded intracellular Gli activities in Hedgehog signaling

Graded Hedgehog (Hh) signaling governs the balance of Gli transcriptional activators and repressors to specify diverse ventral cell fates in the spinal cord. It remains unclear how distinct intracellular Gli activity is generated. Here, we demonstrate that Sufu acts universally as a negative regulator of Hh signaling, whereas Kif7 inhibits Gli activity in cooperation with, and independent of, Sufu. Together, they deter naïve precursors from acquiring increasingly ventral identity. We show that Kif7 is also required to establish high intracellular Gli activity by antagonizing the Sufu-inhibition of Gli2. Strikingly, by abolishing the negative regulatory action of Sufu, diverse ventral cell fates can be specified in the absence of extracellular Hh signaling. These data suggest that Sufu is the primary regulator of graded Hh signaling and establish that the antagonistic and cooperative actions of Kif7 and Sufu are responsible for setting up distinct Gli activity in ventral cell fate specification.

Disruption at the PTCHD1 Locus on Xp22.11 in Autism spectrum disorder and intellectual disability

Autism is a common neurodevelopmental disorder with a complex mode of inheritance. It is one of the most highly heritable of the complex disorders, although the underlying genetic factors remain largely unknown. Here, we report mutations in the X-chromosome PTCHD1 (patched-related) gene in seven families with autism spectrum disorder (ASD) and in three families with intellectual disability. A 167-kilobase microdeletion spanning exon 1 was found in two brothers, one with ASD and the other with a learning disability and ASD features; a 90-kilobase microdeletion spanning the entire gene was found in three males with intellectual disability in a second family. In 900 probands with ASD and 208 male probands with intellectual disability, we identified seven different missense changes (in eight male probands) that were inherited from unaffected mothers and not found in controls. Two of the ASD individuals with missense changes also carried a de novo deletion at another ASD susceptibility locus (DPYD and DPP6), suggesting complex genetic contributions. In additional males with ASD, we identified deletions in the 5' flanking region of PTCHD1 that disrupted a complex noncoding RNA and potential regulatory elements; equivalent changes were not found in male control individuals. Thus, our systematic screen of PTCHD1 and its 5' flanking regions suggests that this locus is involved in ~1% of individuals with ASD and intellectual disability.

[Study of incidence and correlation factors of depression, anxiety and insomnia in patients with myasthenia gravis]

OBJECTIVE

To investigate the incidence rate and correlation factors of depression, anxiety and insomnia in patients with myasthenia gravis (MG).

METHODS

A total of 161 MG patients were assessed and graded with HAMD, HAMA, PSQI, QMG, ADL and a self-made scale chart. And the correlation factors were analyzed by Logistic stepwise regression.

RESULTS

The prevalence of depression, anxiety and insomnia was 58.3%, 45.3% and 39.1% respectively. The correlation factors with significant influences on MG were as follows: depression with age, physical weakness, score of QMG, life scale grading; anxiety with experience-sharing; insomnia age, dyspnea, thymoma, physical status at 1 month post-operation, prednisone dose and score of QMG.

CONCLUSION

Nearly one half of the MG patients suffer from affective disorders to different degrees. And an analysis of its correlation factors provides references to prevent and treat the affective disorders concurrently with MG.

The Bergen Blood Pressure Study: Definition of Hypertensive and Normotensive Families Based on 27 Years' Follow-up

The familial aggregation of hypertension is well documented. However, many studies on the familial predisposition have suffered from insufficient knowledge of parental blood pressure (BP). In the present study, the family history is defined according to parental data from two BP surveys conducted almost 30 years apart. Data from a population screening in Bergen in 1963-64 were linked with information on marital status to define couples with or without a history of hypertension. Within the screened population a total of 344 married couples, 688 individuals, matched defined age and BP criteria. Four hundred and thirty individuals, representing 270 of the 344 families initial included (79%), attended a follow-up examination in 1990. Six hundred and ninety-one offspring were registered. In all families represented at follow-up, parental BP data from the 1963-64 screening were available. In 160 families (noffspring = 393), both parents also attended the follow-up examination in 1990. In 23 families (noffspring = 54) both parents were hypertensive in 1963-64 as well as in 1990. In 22 families (noffspring = 55) both parents were normotensive at both examinations. Thus, a family data base which is assumed to be useful for studies on offspring with or without a family history of hypertension, has been established. The offspring studies include BP, 24-h ambulatory BP, electrocardiography, echocardiography, endocrine parameters, electrolytes and anthropometric variables.

The kinesin protein Kif7 is a critical regulator of Gli transcription factors in mammalian hedgehog signaling

From insects to humans, the Hedgehog (Hh) signaling pathway has conserved roles in embryonic development and tissue homeostasis. However, it has been suggested that the lack of mammalian equivalents of Costal2 (Cos2) contributes to a divergence between the mechanism of Drosophila and mammalian Hh signal transduction. Here, we challenge this view by showing that the kinesin protein Kif7 is a critical regulator of Hh signaling in mice. Similar to Cos2, Kif7 physically interacted with Gli transcription factors and controlled their proteolysis and stability, and acted both positively and negatively in Hh signaling. Thus, Kif7 is a missing component of the mammalian Hh signaling machinery, implying a greater commonality between the Drosophila and mammalian system than the prevailing view suggests.

Dusty protein kinases: primary structure, gene evolution, tissue specific expression and unique features of the catalytic domain

Ser/Thr- and Tyr-Protein kinases constitute a key switch underlying the dynamic nature and graded regulation of signal transduction and pathway activities in cellular organization. Here we describe the identification and characterization of Dusty, a single-copy gene that arose in metazoan evolution and encodes a putative dual Ser/Thr and Tyr protein kinase with unique structural features. Dusty is widely expressed in vertebrates, broadly distributed in the central nervous system, and deregulated in certain human cancers. Confocal imaging of transiently expressed human Dusty-GFP fusion proteins showed a cytoplasmic distribution. Dusty proteins from lower to higher species display an increasing degree of sequence conservation from the N-terminal non-catalytic domain to C-terminal catalytic domain. The non-catalytic region has eight conserved cysteine residues, multiple potential kinase-docking motifs and phosphorylation sites, whereas the catalytic domain is divergent and about equally distant of Ser/Thr and Tyr protein kinases. Homology analyses identified the essential catalytic residues, suggesting that Dusty homologues all possess the enzymatic activity of a protein kinase. Taken together, Dusty is a unique evolutionarily selected group of divergent protein kinases that may play important functional roles in the brain and other tissues of vertebrates.

Mice with a targeted mutation of patched2 are viable but develop alopecia and epidermal hyperplasia

Hedgehog (Hh) signaling plays pivotal roles in tissue patterning and development in Drosophila melanogaster and vertebrates. The Patched1 (Ptc1) gene, encoding the Hh receptor, is mutated in nevoid basal cell carcinoma syndrome, a human genetic disorder associated with developmental abnormalities and increased incidences of basal cell carcinoma (BCC) and medulloblastoma (MB). Ptc1 mutations also occur in sporadic forms of BCC and MB. Mutational studies with mice have verified that Ptc1 is a tumor suppressor. We previously identified a second mammalian Patched gene, Ptc2, and demonstrated its distinct expression pattern during embryogenesis, suggesting a unique role in development. Most notably, Ptc2 is expressed in an overlapping pattern with Shh in the epidermal compartment of developing hair follicles and is highly expressed in the developing limb bud, cerebellum, and testis. Here, we describe the generation and phenotypic analysis of Ptc2(tm1/tm1) mice. Our molecular analysis suggests that Ptc2(tm1) likely represents a hypomorphic allele. Despite the dynamic expression of Ptc2 during embryogenesis, Ptc2(tm1/tm1) mice are viable, fertile, and apparently normal. Interestingly, adult Ptc2(tm1/tm1) male animals develop skin lesions consisting of alopecia, ulceration, and epidermal hyperplasia. While functional compensation by Ptc1 might account for the lack of a strong mutant phenotype in Ptc2-deficient mice, our results suggest that normal Ptc2 function is required for adult skin homeostasis.

Gli2 and Gli3 play distinct roles in the dorsoventral patterning of the mouse hindbrain

Sonic Hedgehog (Shh) signaling plays a critical role during dorsoventral (DV) patterning of the developing neural tube by modulating the expression of neural patterning genes. Overlapping activator functions of Gli2 and Gli3 have been shown to be required for motoneuron development and correct neural patterning in the ventral spinal cord. However, the role of Gli2 and Gli3 in ventral hindbrain development is unclear. In this paper, we have examined DV patterning of the hindbrain of Shh(-/-), Gli2(-/-) and Gli3(-/-) embryos, and found that the respective role of Gli2 and Gli3 is not only different between the hindbrain and spinal cord, but also at distinct rostrocaudal levels of the hindbrain. Remarkably, the anterior hindbrain of Gli2(-/-) embryos displays ventral patterning defects as severe as those observed in Shh(-/-) embryos suggesting that, unlike in the spinal cord and posterior hindbrain, Gli3 cannot compensate for the loss of Gli2 activator function in Shh-dependent ventral patterning of the anterior hindbrain. Loss of Gli3 also results in a distinct patterning defect in the anterior hindbrain, including dorsal expansion of Nkx6.1 expression. Furthermore, we demonstrate that ventral patterning of rhombomere 4 is less affected by loss of Gli2 function revealing a different requirement for Gli proteins in this rhombomere. Taken together, these observations indicate that Gli2 and Gli3 perform rhombomere-specific function during DV patterning of the hindbrain.

Gli3 null mice display glandular overgrowth of the developing stomach

The role of the Hedgehog signaling pathway in various aspects of gut development is still poorly understood. In the developing stomach, Sonic (Shh) and Indian (Ihh) hedgehog are expressed in both distinct and overlapping regions. Loss of Sonic hedgehog function in the stomach results in a glandular phenotype of intestinal transformation and overgrowth. These changes are reminiscent of the pre-malignant lesion, intestinal metaplasia. To determine the role of Hedgehog-related transcription factors, Gli2 and Gli3, in Shh signaling during stomach development, we conducted a mutant analysis of glandular stomach from Shh, Gli2, and Gli3 mutant mice. Although Gli2 principally mediates the activator function of Shh, surprisingly we observed minimal changes in glandular development in the Gli2 mutant stomach. Furthermore, Gli3, which typically functions as a repressor of Hedgehog signal, showed a striking phenocopy of the glandular expansion and intestinal transformation found in Shh mutant stomach. A reduction in apoptotic events was seen in all mutant stomachs with no appreciable changes in proliferation. Both Shh and Gli3 mutant stomachs displayed early changes of intestinal transformation but these did not impact on the overall differentiation of the gastric epithelium. Interestingly, the observation that Gli3 shares a similar glandular phenotype to Shh mutant stomach reveals a possible novel role of Gli3 activator in the developing stomach. The embryonic stomach is a unique model of the Hedgehog pathway function and one that may help to uncover some of the mechanisms underlying the development of intestinal metaplasia.

GLI3-dependent transcriptional repression of Gli1, Gli2 and kidney patterning genes disrupts renal morphogenesis

Truncating mutations in Gli3, an intracellular effector in the SHH-SMO-GLI signaling pathway, cause renal aplasia/dysplasia in humans and mice. Yet, the pathogenic mechanisms are undefined. Here, we report the effect of decreased SHH-SMO signaling on renal morphogenesis, the expression of SHH target genes and GLI binding to Shh target genes. Shh deficiency or cyclopamine-mediated SMO inhibition disrupted renal organogenesis, decreased expression of GLI1 and GLI2 proteins, but increased expression of GLI3 repressor relative to GLI3 activator. Shh deficiency decreased expression of kidney patterning genes (Pax2 and Sall1) and cell cycle regulators (cyclin D1 and MYCN). Elimination of Gli3 in Shh(-/-) mice rescued kidney malformation and restored expression of Pax2, Sall1, cyclin D1, MYCN, Gli1 and Gli2. To define mechanisms by which SHH-SMO signaling controls gene expression, we determined the binding of GLI proteins to 5' flanking regions containing GLI consensus binding sequences in Shh target genes using chromatin immunoprecipitation. In normal embryonic kidney tissue, GLI1 and/or GLI2 were bound to each target gene. By contrast, treatment of embryonic kidney explants with cyclopamine decreased GLI1 and/or GLI2 binding, and induced binding of GLI3. However, cyclopamine failed to decrease Gli1 and Gli2 expression and branching morphogenesis in Gli3-deficient embryonic kidney tissue. Together, these results demonstrate that SHH-SMO signaling controls renal morphogenesis via transcriptional control of Gli, renal patterning and cell cycle regulator genes in a manner that is opposed by GLI3.

Cooperative and antagonistic interactions between Sall4 and Tbx5 pattern the mouse limb and heart

Human mutations in TBX5, a gene encoding a T-box transcription factor, and SALL4, a gene encoding a zinc-finger transcription factor, cause similar upper limb and heart defects. Here we show that Tbx5 regulates Sall4 expression in the developing mouse forelimb and heart; mice heterozygous for a gene trap allele of Sall4 show limb and heart defects that model human disease. Tbx5 and Sall4 interact both positively and negatively to finely regulate patterning and morphogenesis of the anterior forelimb and heart. Thus, a positive and negative feed-forward circuit between Tbx5 and Sall4 ensures precise patterning of embryonic limb and heart and provides a unifying mechanism for heart/hand syndromes.

Pax9 and Jagged1 act downstream of Gli3 in vertebrate limb development

From early in limb development the transcription factor Gli3 acts to define boundaries of gene expression along the anterior-posterior (AP) axis, establishing asymmetric patterns required to provide positional information. As limb development proceeds, posterior mesenchyme expression of Sonic hedgehog (Shh) regulates Gli3 transcription and post-translational processing to specify digit number and identity. The molecular cascades dependent on Gli3 at later stages of limb development, which link early patterning events with final digit morphogenesis, remain poorly characterised. By analysing the transcriptional consequences of loss of Gli3 in the anterior margin of the E11.5 and E12.5 limb bud in the polydactylous mouse mutant extra-toes (Gli3(Xt/Xt)), we have identified a number of known and novel transcripts dependent on Gli3 in the limb. In particular, we demonstrated that the genes encoding the paired box transcription factor Pax9, the Notch ligand Jagged1 and the cell surface receptor Cdo are dependent on Gli3 for correct expression in the anterior limb mesenchyme. Analysis of expression in compound Shh;Gli3 mutant mouse embryos and in both in vitro and in vivo Shh signaling assays, further defined the importance of Shh regulated processing of Gli3 in controlling gene expression. In particular Pax9 regulation by Shh and Gli3 was shown to be context dependent, with major differences between the limb and somite revealed by Shh bead implantation experiments in the chick. Jagged1 was shown to be induced by Shh in the chick limb and in a C3H10T1/2 cell based signaling assay, with Shh;Gli3 mutant analysis indicating that expression is dependent on Gli3 derepression. Our data have also revealed that perturbation of early patterning events within the Gli3(Xt/Xt) limb culminates in a specific delay of anterior chondrogenesis which is subsequently realised as extra digits.

Shh controls epithelial proliferation via independent pathways that converge on N-Myc

Shh signaling induces proliferation of many cell types during development and disease, but how Gli transcription factors regulate these mitogenic responses remains unclear. By genetically altering levels of Gli activator and repressor functions in mice, we have demonstrated that both Gli functions are involved in the transcriptional control of N-myc and Cyclin D2 during embryonic hair follicle development. Our results also indicate that additional Gli-activator-dependent functions are required for robust mitogenic responses in regions of high Shh signaling. Through posttranscriptional mechanisms, including inhibition of GSK3-beta activity, Shh signaling leads to spatially restricted accumulation of N-myc and coordinated cell cycle progression. Furthermore, a temporal shift in the regulation of GSK3-beta activity occurs during embryonic hair follicle development, resulting in a synergy with beta-catenin signaling to promote coordinated proliferation. These findings demonstrate that Shh signaling controls the rapid and patterned expansion of epithelial progenitors through convergent Gli-mediated regulation.

Tbx20 dose-dependently regulates transcription factor networks required for mouse heart and motoneuron development

To elucidate the function of the T-box transcription factor Tbx20 in mammalian development, we generated a graded loss-of-function series by transgenic RNA interference in entirely embryonic stem cell-derived mouse embryos. Complete Tbx20 knockdown resulted in defects in heart formation, including hypoplasia of the outflow tract and right ventricle, which derive from the anterior heart field (AHF), and decreased expression of Nkx2-5 and Mef2c, transcription factors required for AHF formation. A mild knockdown led to persistent truncus arteriosus (unseptated outflow tract) and hypoplastic right ventricle, entities similar to human congenital heart defects, and demonstrated a critical requirement for Tbx20 in valve formation. Finally, an intermediate knockdown revealed a role for Tbx20 in motoneuron development, specifically in the regulation of the transcription factors Isl2 and Hb9, which are important for terminal differentiation of motoneurons. Tbx20 could activate promoters/enhancers of several genes in cultured cells, including the Mef2c AHF enhancer and the Nkx2-5 cardiac enhancer. The Mef2c AHF enhancer relies on Isl1- and Gata-binding sites. We identified a similar Isl1 binding site in the Nkx2-5 AHF enhancer, which in transgenic mouse embryos was essential for activity in a large part of the heart, including the outflow tract. Tbx20 synergized with Isl1 and Gata4 to activate both the Mef2c and Nkx2-5 enhancers, thus providing a unifying mechanism for gene activation by Tbx20 in the AHF. We conclude that Tbx20 is positioned at a critical node in transcription factor networks required for heart and motoneuron development where it dose-dependently regulates gene expression.