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•A bifunctional Ru–Pd catalyst was synthesized by a facile impregnation–hydrogen reduction method.•The catalyst has excellent catalytic activity for both hydrogenation and ...dehydrogenation of LOHCs.•No significant activity decrease was observed after several hydrogenation and dehydrogenation cycles.•The dehydrogenation activity of the Ru–Pd/Al2O3 catalyst is superior to that of a commercial Pd–Al2O3 catalyst.
Hydrogen storage and release by liquid organic hydrogen carriers (LOHCs) are achieved by a reversible catalytic hydrogenation and dehydrogenation process. Generally, catalytic hydrogenation and catalytic dehydrogenation require different noble metal catalysts. In this paper, we report a bifunctional Ru–Pd/Al2O3 catalyst with excellent catalytic activity for both hydrogenation and dehydrogenation of LOHCs. All catalysts were prepared by a facile impregnation–hydrogen reduction method, and the catalytic activities were compared by catalytic hydrogenation of N-propylcarbazole and dehydrogenation of perhydro-N-propylcarbazole. The as-prepared Ru-Pd/Al2O3 catalyst exhibits excellent catalytic hydrogenation and dehydrogenation activity, selectivity, and stability. Particularly, the dehydrogenation activity of the Ru–Pd/Al2O3 catalyst is superior to that of the commercial Pd/Al2O3 catalyst, which proves that the positive synergistic effect between palladium and ruthenium nanoparticles enhanced the activity of the Ru–Pd/Al2O3 catalyst. No significant activity decrease was observed for the as-prepared catalysts after three cycles of N-propylcarbazole hydrogenation and three cycles of dehydrogenation. The bifunctional Ru–Pd catalyst has potential commercial applications in large-scale application of LOHC technology.
Abstract
Sclerostin negatively regulates bone formation by antagonizing Wnt signalling. An antibody targeting sclerostin for the treatment of postmenopausal osteoporosis was approved by the U.S. Food ...and Drug Administration, with a boxed warning for cardiovascular risk. Here we demonstrate that sclerostin participates in protecting cardiovascular system and inhibiting bone formation via different loops. Loop3 deficiency by genetic truncation could maintain sclerostin’s protective effect on the cardiovascular system while attenuating its inhibitory effect on bone formation. We identify an aptamer, named aptscl56, which specifically targets sclerostin loop3 and use a modified aptscl56 version, called Apc001PE, as specific in vivo pharmacologic tool to validate the above effect of loop3. Apc001PE has no effect on aortic aneurysm and atherosclerotic development in
ApoE
−/−
mice and
hSOST
ki
.ApoE
−/−
mice with angiotensin II infusion. Apc001PE can promote bone formation in
hSOST
ki
mice and ovariectomy-induced osteoporotic rats. In summary, sclerostin loop3 cannot participate in protecting the cardiovascular system, but participates in inhibiting bone formation.
Spinal muscular atrophy, lower extremity predominant (SMALED) is a type of non-5q spinal muscular atrophy characterised by weakness and atrophy of lower limb muscles without sensory abnormalities. ...SMALED1 can be caused by dynein cytoplasmic 1 heavy chain 1 (DYNC1H1) gene variants. However, the phenotype and genotype of SMALED1 may overlap with those of other neuromuscular diseases, making it difficult to diagnose clinically. Additionally, bone metabolism and bone mineral density (BMD) in patients with SMALED1 have never been reported.
We investigated a Chinese family in which 5 individuals from 3 generations had lower limb muscle atrophy and foot deformities. Clinical manifestations and biochemical and radiographic indices were analysed, and mutational analysis was performed by whole-exome sequencing (WES) and Sanger sequencing.
A novel mutation in exon 4 of the DYNC1H1 gene (c.587T > C, p.Leu196Ser) was identified in the proband and his affected mother by WES. Sanger sequencing confirmed that the proband and 3 affected family members were carriers of this mutation. As leucine is a hydrophobic amino acid and serine is hydrophilic, the hydrophobic interaction resulting from mutation of amino acid residue 196 could influence the stability of the DYNC1H1 protein. Leg muscle magnetic resonance imaging of the proband revealed severe atrophy and fatty infiltration, and electromyographic recordings showed chronic neurogenic impairment of the lower extremities. Bone metabolism markers and BMD of the proband were all within normal ranges. None of the 4 patients had experienced fragility fractures.
This study identified a novel DYNC1H1 mutation and expands the spectrum of phenotypes and genotypes of DYNC1H1-related disorders. This is the first report of bone metabolism and BMD in patients with SMALED1.
The development of switchable adhesives for reversible bonding and debonding can overcome the problems associated with conventional adhesives in separating, recycling, and repairing glued surfaces. ...Here, a photoresponsive azobenzene-containing polymer (azopolymer) is developed for photocontrolled adhesion. The azopolymer P1 (poly(6-(4-(p-tolyldiazenyl)phenoxy)hexyl acrylate)) exhibits photoinduced reversible solid-to-liquid transitions due to trans–cis photoisomerization. Trans P1 is a solid that glues two substrates with a stiffness comparable to that of conventional adhesives. UV light induces trans-to-cis isomerization, liquefies P1, weakens the adhesion, and facilitates the separation of glued substrates. Conversely, visible light induces cis-to-trans isomerization, solidifies P1, and enhances the adhesion. P1 enables photocontrolled reversible adhesion for various substrates with different wettability, chemical compositions, and surface roughness. P1 can also be implemented in both dry and wet environments. Light can control the adhesion process with high spatiotemporal resolution when using P1 as a switchable adhesive. Photoinduced reversible solid-to-liquid transitions represent a strategy for materials recycling and automated production processes that require reversible bonding and debonding.
Very little is known about the characteristics of echocardiographic abnormalities and joint hypermobility in Chinese patients with osteogenesis imperfecta (OI). The aim of our study was to ...investigate the characteristics, prevalence and correlation of echocardiographic abnormalities and joint hypermobility in Chinese patients with OI.
A cross-sectional comparative study was conducted in pediatric and adult OI patients who were matched in age and sex with healthy controls. Transthoracic echocardiography was performed in all patients and controls, and parameters were indexed for body surface area (BSA). The Beighton score was used to evaluate the degree of joint hypermobility.
A total of 48 patients with OI (25 juveniles and 23 adults) and 129 age- and sex-matched healthy controls (79 juveniles and 50 adults) were studied. Four genes (COL1A1, COL1A2, IFITM5, and WNT1) and 39 different mutation loci were identified in our study. Mild valvular regurgitation was the most common cardiac abnormality: mild mitral and tricuspid regurgitation was found in 12% and 36% of pediatric OI patients, respectively; among 23 OI adults, 13% and 17% of patients had mild mitral and tricuspid regurgitation, respectively, and 4% had mild aortic regurgitation. In multiple regression analysis, OI was the key predictor of left atrium diameter (LAD) (β=-3.670, P < 0.001) and fractional shortening (FS) (β = 3.005, P = 0.037) in juveniles, whereas for adults, OI was a significant predictor of LAD (β=-3.621, P < 0.001) and left ventricular mass (LVM) (β = 58.928, P < 0.001). The percentages of generalized joint hypermobility in OI juveniles and adults were 56% and 20%, respectively. Additionally, only in the OI juvenile group did the results of the Mann‒Whitney U test show that the degree of joint hypermobility was significantly different between the echocardiographic normal and abnormal groups (P = 0.004).
Mild valvular regurgitation was the most common cardiac abnormality in both OI juveniles and adults. Compared with OI adults, OI juveniles had more prevalent and wider joint hypermobility. Echocardiographic abnormalities may imply that the impairment of type I collagen is more serious in OI. Baseline echocardiography should be performed in OI patients as early as possible.
Purpose
Nearly 85%-90% of osteogenesis imperfecta (OI) cases are caused by autosome dominant mutations of
COL1A1
and
COL1A2
genes, of which
de novo
mutations cover a large proportion, whereas their ...characteristics remain to be elucidated. This study aims to compare the differences in clinical and genetic characteristics of
de novo
and inherited
COL1A1/COL1A2
mutations of OI, assess the average paternal and maternal age at conception in
de novo
mutations, and research the rate of nonpenetrance in inherited mutations.
Materials and Methods
A retrospective comparison between
de novo
and inherited mutations was performed among 135 OI probands with
COL1A1/COL1A2
mutations. Mutational analyses of all probands and their family members were completed by Sanger sequencing. A new clinical scoring system was developed to assess the clinical severity of OI quantitatively.
Results
A total of 51 probands (37.78%) with
de novo
mutations and 84 probands (62.22%) with inherited mutations were grouped by the results of the parental gene verification. The proportion of clinical type III (
P
<0.001) and clinical scores (
P
<0.001) were significantly higher in
de novo
mutations. Missense mutations covered a slightly higher proportion of
de novo COL1A1
mutations (46.34%) compared with inherited
COL1A1
mutations (33.33%), however, lacking a significant difference (
P
=0.1923). The mean BMD Z/T-score at the lumbar spine in
de novo
mutations was -2.3 ± 1.5, lower than inherited mutations (-1.7 ± 1.8), but lacking statistical significance (
P
=0.0742). There was no significant difference between the two groups in OI-related phenotypes (like fracture frequency, blue sclera, and hearing loss) and biochemical indexes. In
de novo
mutations, the average paternal and maternal age at conception was 29.2 (
P
<0.05) and 26.8 (
P
<0.0001), respectively, which were significantly younger than the average gestational age of the population. Additionally, 98.04% of pedigrees (50/51) with
de novo
mutations were spontaneous conception. The rate of nonpenetrance of parents with pathogenic variants in the inherited mutation group was 25.64% (20/78).
Conclusions
Our data revealed that the proportion of clinical type III and clinical scores were significantly higher in
de novo
mutations than in inherited mutations, demonstrating that
de novo
mutations are more damaging because they have not undergone purifying selection.
Primary hypertrophic osteoarthropathy (PHO) is a genetic disorder mainly characterized by clubbing fingers, pachydermia and periostosis. Mutations in the
HPGD
or
SLCO2A1
gene lead to impaired ...prostaglandin E2 (PGE2) degradation, thus elevating PGE2 levels. The identification of the causative genes has provided a better understanding of the underlying mechanisms. PHO can be divided into three subtypes according to its pathogenic gene and inheritance patterns. The onset age, sex ratio and clinical features differ among subtypes. The synthesis and signaling pathways of PGE2 are outlined in this review. Cyclooxygenase-2 (COX-2) is the key enzyme that acts as the rate-limiting step for prostaglandin production, thus COX-2 inhibitors have been used to treat this disease. Although this treatment showed effective results, it has side effects that restrain its use. Here, we reviewed the genetics, clinical features, differential diagnosis and current treatment options of PHO according to our many years of clinical research on the disease. We also discussed probable treatment that may be an option in the future.
Indian Hedgehog (IHH) signaling, a key regulator of skeletal development, is highly activated in cartilage and bone tumors. Yet deletion of
, encoding an inhibitor of IHH receptor Smoothened (SMO), ...in chondrocyte or osteoblasts does not cause tumorigenesis. Here, we show that
deletion in mice Prrx1
mesenchymal stem/stromal cells (MSCs) promotes MSC proliferation and osteogenic and chondrogenic differentiation but inhibits adipogenic differentiation. Moreover,
deletion led to development of osteoarthritis-like phenotypes, exostoses, enchondroma, and osteosarcoma in Smo-Gli1/2-dependent manners. The cartilage and bone tumors are originated from Prrx1
lineage cells and express low levels of osteoblast and chondrocyte markers, respectively. Mechanistically,
deletion increases the expression of Wnt5a/6 and leads to enhanced β-Catenin activation. Inhibiting Wnt/β-Catenin pathway suppresses development of skeletal anomalies including enchondroma and osteosarcoma. These findings suggest that cartilage/bone tumors arise from their early progenitor cells and identify the Wnt/β-Catenin pathway as a pharmacological target for cartilage/bone neoplasms.
A paraxial powder-feeding system by employing a quasi-continuous fiber laser machine was established to repair non-weldable nickel-based K447A alloy. In the present study, the duty cycle (DC) of the ...pulsed-wave laser was chosen to reveal the influence on hot cracking. The results showed that the total length of hot cracking on the 10.5 mm-length longitudinal section of the cladding zone reduces from 3.263 mm to 0.092 mm with the decline of DC from 80% to 30%. The intermittent occurrence of the laser beam induced the ripple microstructure in the cladding layer (CL). It is the high cooling rate in laser extinguishment process that caused the fine dendrite zone which provides more resistance for hot cracking propagation in the CL. The liquid film in the heat-affected zone (HAZ) mainly results from the M5B3/γ, γ′/γ, and MC/γ constitutional liquation successively among 1200–1300 °C. Heat input is the main factor affecting hot cracking in the HAZ. With the decrease of DC, the dendrite spacing of the fine dendrite zone decreases in the CL, and the depth of liquefaction zone decreases in the HAZ, as a result, the length of hot cracking in the CL and HAZ both decreases.
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•Duty cycle of the pulsed-wave laser was chosen to reveal the influence on hot cracking.•The influence of ripple characteristics on hot cracking propagation in the cladding layer was revealed.•The intergranular liquation mechanism of a non-weldable nickel-based alloy was clarified as detailed.
Introduction
This study aimed to investigate the relationship of gene polymorphisms and fat mass (FM) in Chinese population.
Material and methods
Healthy males, premenopausal and postmenopausal women ...were recruited. Single Nucleotide Polymorphisms (SNPs) and FM were measured.
Results
The rs141206415 in the RASAL1 gene and rs144493374 in the PALLD gene were associated with trunk FM, and the rs4807023 in the PTPRS gene was associated with leg FM using Spearman correlation analysis.
Conclusions
The results suggest that the RASAL1 gene and the PALLD gene might contribute to variability of trunk FM in healthy Chinese Han people. The PTPRS gene is potentially correlated with leg FM. Our findings provide a clue in fat metabolism.
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