DGAT2 Mutation in a Family with Autosomal-Dominant Early-Onset Axonal Charcot-Marie-Tooth Disease.

Charcot-Marie-Tooth disease (CMT) is the most common inherited peripheral neuropathy and is a genetically and clinically heterogeneous disorder. We examined a Korean family in which two individuals had an autosomal-dominant axonal CMT with early-onset, sensory ataxia, tremor, and slow disease progression. Pedigree analysis and exome sequencing identified a de novo missense mutation (p.Y223H) in the diacylglycerol O-acyltransferase 2 (DGAT2) gene. DGAT2 encodes an endoplasmic reticulum-mitochondrial-associated membrane protein, acyl-CoA:diacylglycerol acyltransferase, which catalyzes the final step of the triglyceride (TG) biosynthesis pathway. The patient showed consistently decreased serum TG levels, and overexpression of the mutant DGAT2 significantly inhibited the proliferation of mouse motor neuron cells. Moreover, the variant form of human DGAT2 inhibited the axonal branching in the peripheral nervous system of zebrafish. We suggest that mutation of DGAT2 is the novel underlying cause of an autosomal-dominant axonal CMT2 neuropathy. This study will help provide a better understanding of the pathophysiology of axonal CMT and contribute to the molecular diagnostics of peripheral neuropathies.

Intrinsic and extrinsic mechanical properties related to the differentiation of mesenchymal stem cells.

Diverse intrinsic and extrinsic mechanical factors have a strong influence on the regulation of stem cell fate. In this work, we examined recent literature on the effects of mechanical environments on stem cells, especially on differentiation of mesenchymal stem cells (MSCs). We provide a brief review of intrinsic mechanical properties of single MSC and examined the correlation between the intrinsic mechanical property of MSC and the differentiation ability. The effects of extrinsic mechanical factors relevant to the differentiation of MSCs were considered separately. The effect of nanostructure and elasticity of the matrix on the differentiation of MSCs were summarized. Finally, we consider how the extrinsic mechanical properties transfer to MSCs and then how the effects on the intrinsic mechanical properties affect stem cell differentiation.

Immunomodulatory properties and in vivo osteogenesis of human dental stem cells from fresh and cryopreserved dental follicles.

In our previous study, dental follicle tissues from extracted wisdom teeth were successfully cryopreserved for use as a source of stem cells. The goals of the present study were to investigate the immunomodulatory properties of stem cells from fresh and cryopreserved dental follicles (fDFCs and cDFCs, respectively) and to analyze in vivo osteogenesis after transplantation of these DFCs into experimental animals. Third passage fDFCs and cDFCs showed similar expression levels of interferon-γ receptor (CD119) and major histocompatibility complex class I and II (MHC I and MHC II, respectively), with high levels of CD119 and MHC I and nearly no expression of MHC II. Both fresh and cryopreserved human DFCs (hDFCs) were in vivo transplanted along with a demineralized bone matrix scaffold into mandibular defects in miniature pigs and subcutaneous tissues of mice. Radiological and histological evaluations of in vivo osteogenesis in hDFC-transplanted sites revealed significantly enhanced new bone formation activities compared with those in scaffold-only implanted control sites. Interestingly, at 8 weeks post-hDFC transplantation, the newly generated bones were overgrown compared to the original size of the mandibular defects, and strong expression of osteocalcin and vascular endothelial growth factor were detected in the hDFCs-transplanted tissues of both animals. Immunohistochemical analysis of CD3, CD4, and CD8 in the ectopic bone formation sites of mice showed significantly decreased CD4 expression in DFCs-implanted tissues compared with those in control sites. These findings indicate that hDFCs possess immunomodulatory properties that involved inhibition of the adaptive immune response mediated by CD4 and MHC II, which highlights the usefulness of hDFCs in tissue engineering. In particular, long-term preserved dental follicles could serve as an excellent autologous or allogenic stem cell source for bone tissue regeneration as well as a valuable therapeutic agent for immune diseases.

Charcot-Marie-Tooth Disease Type 4H Resulting from Compound Heterozygous Mutations in FGD4 from Nonconsanguineous Korean Families.

Charcot-Marie-Tooth disease type 4H (CMT4H) is an autosomal recessive demyelinating subtype of peripheral enuropathies caused by mutations in the FGD4 gene. Most CMT4H patients are in consanguineous Mediterranean families characterized by early onset and slow progression. We identified two CMT4H patients from a Korean CMT cohort, and performed a detailed genetic and clinical analysis in both cases. Both patients from nonconsanguineous families showed characteristic clinical manifestations of CMT4H including early onset, scoliosis, areflexia, and slow disease progression. Exome sequencing revealed novel compound heterozygous mutations in FGD4 as the underlying cause in both families (p.Arg468Gln and c.1512-2A>C in FC73, p.Met345Thr and c.2043+1G>A (p.Trp663Trpfs*30) in FC646). The missense mutations were located in highly conserved RhoGEF and PH domains which were predicted to be pathogenic in nature by in silico modeling. The CMT4H occurrence frequency was calculated to 0.7% in the Korean demyelinating CMT patients. This study is the first report of CMT4H in Korea. FGD4 assay could be considered as a means of molecular diagnosis for sporadic cases of demyelinating CMT with slow progression.

Severe phenotypes in a Charcot-Marie-Tooth 1A patient with PMP22 triplication.

Charcot-Marie-Tooth disease (CMT) is a genetically and clinically heterogeneous hereditary motor and sensory neuropathy signified by a distal symmetric polyneuropathy. The most frequent subtype is type 1A (CMT1A) caused by duplication in chromosome 17p12 that includes PMP22. This study reports a woman with a family history of CMT1A due to PMP22 duplication. However, she presented with a more severe phenotype than her sibling or ancestors and was found to have a PMP22 triplication instead of the duplication. This was caused by de novo mutation on her affected mother's duplication chromosome. Her lower limb magnetic resonance imaging revealed severe diffused atrophy and fatty replacement. However, her affected sister with typical PMP22 duplication showed almost intact lower limb. Triplication patient's median motor nerve conduction velocity was far lower compared with her sister. Her onset age was faster (8 years) than her sister (42 years). CMT1A triplication might be generated by a female-specific chromosomal rearrangement mechanism that is different from the frequent paternal-originated CMT1A duplication. It also suggests that the wide phenotypic variation of CMT1A might be partly caused by unstable genomic rearrangement, including PMP22 triplication.

Overexpression of mutant HSP27 causes axonal neuropathy in mice.

BACKGROUND: Mutations in heat shock 27 kDa protein 1 (HSP27 or HSPB1) cause distal hereditary motor neuropathy (dHMN) or Charcot-Marie-Tooth disease type 2 F (CMT2F) according to unknown factors. Mutant HSP27 proteins affect axonal transport by reducing acetylated tubulin. RESULTS: We generated a transgenic mouse model overexpressing HSP27-S135F mutant protein driven by Cytomegalovirus (CMV) immediate early promoter. The mouse phenotype was similar to dHMN patients in that they exhibit motor neuropathy. To determine the phenotypic aberration of transgenic mice, behavior test, magnetic resonance imaging (MRI), electrophysiological study, and pathology were performed. Rotarod test showed that founder mice exhibited lowered motor performance. MRI also revealed marked fatty infiltration in the anterior and posterior compartments at calf level. Electrophysiologically, compound muscle action potential (CMAP) but not motor nerve conduction velocity (MNCV) was reduced in the transgenic mice. Toluidine staining with semi-thin section of sciatic nerve showed the ratio of large myelinated axon fiber was reduced, which might cause reduced locomotion in the transgenic mice. Electron microscopy also revealed abundant aberrant myelination. Immunohistochemically, neuronal dysfunctions included elevated level of phosphorylated neurofilament and reduced level of acetylated tubulin in the sural nerve of transgenic mice. There was no additional phenotype besides motor neuronal defects. CONCLUSIONS: Overexpression of HSP27-S135F protein causes peripheral neuropathy. The mouse model can be applied to future development of therapeutic strategies for dHMN or CMT2F.

A novel homozygous MPV17 mutation in two families with axonal sensorimotor polyneuropathy.

BACKGROUND: Mutations in MPV17 cause the autosomal recessive disorder mitochondrial DNA depletion syndrome 6 (MTDPS6), also called Navajo neurohepatopathy (NNH). Clinical features of MTDPS6 is infantile onset of progressive liver failure with seldom development of progressive neurologic involvement. METHODS: Whole exome sequencing (WES) was performed to isolate the causative gene of two unrelated neuropathy patients (9 and 13 years of age) with onset of the syndrome. Clinical assessments and biochemical analysis were performed. RESULTS: A novel homozygous mutation (p.R41Q) in MPV17 was found by WES in both patients. Both showed axonal sensorimotor polyneuropathy without liver and brain involvement, which is neurophysiologically similar to axonal Charcot-Marie-Tooth disease (CMT). A distal sural nerve biopsy showed an almost complete loss of the large and medium-sized myelinated fibers compatible with axonal neuropathy. An in vitro assay using mouse motor neuronal cells demonstrated that the abrogation of MPV17 significantly affected cell integrity. In addition, the expression of the mutant protein affected cell proliferation. These results imply that both the loss of normal function of MPV17 and the gain of detrimental effects of the mutant protein might affect neuronal function. CONCLUSION: We report a novel homozygous mutation in MPV17 from two unrelated patients harboring axonal sensorimotor polyneuropathy without hepatoencephalopathy. This report expands the clinical spectrum of diseases caused by mutations of MPV17, and we recommend MPV17 gene screening for axonal peripheral neuropathies.

Effectiveness and safety of hominis placental pharmacopuncture for chronic temporomandibular disorder: A multi-center randomized controlled trial.

Background: Hominis placental (HPP) extract has been approved by the Ministry of Food and Drug Safety in Korea for treating chronic liver diseases and postmenopausal syndrome. However, its efficacy and safety for treating chronic temporomandibular disorder (TMD) remains unclear. We aimed to assess the effectiveness and safety of HPP for treating chronic TMD compared with physical therapy (PT). Methods: This study is a 2-arm parallel, multi-center, randomized controlled trial. We enrolled 82 chronic TMD patients from 2 Korean medicine hospitals between December 2019 and January 2021. We included patients with chronic TMD and randomly assigned them to undergo HPP or PT. The primary outcome was the difference in the scores for temporomandibular joint (TMJ) pain at baseline and week 6. The secondary outcomes were the scores for TMJ pain and bothersomeness, TMJ range of motion, the Korean version of Beck's depression index-Ⅱ, jaw functional limitation scale (JFLS) score, patient global impression of change (PGIC) scores, EuroQoL 5-dimension 5-level score, and short form-12 health survey (SF-12) scores. Results: Compared with PT, HPP showed significantly superior effects on TMJ pain and bothersomeness, protrusive movement pain, JFLS (verbal, emotional, and global), SF-12, and PGIC scores at week 6 (P < 0.05). Compared with the PT group, the HPP group showed a significantly higher recovery rate (≥50 % reduction in the scores for TMJ pain at the 24-week follow-up). Conclusion: HPP was more effective than PT managing pain and improving function and quality of life. Our findings demonstrate the effectiveness and safety of HPP for TMD treatment. Trial registration: This study has been registered at clinicalTrials.gov (NCT04087005), Clinical Research Information Service (CRIS) (KCT0004437), and Ministry of Food and Drug Safety (No. 31886).

Nanoscale film formation of recombinant azurin variants with various cysteine residues on gold substrate for bioelectronic device.

Nanoscale film fabrication of recombinant azurin variants with various cysteine residues on gold substrate was developed without any surface modification for bioelectronic device. We have modified azurin with different number of cysteine residues at its amino acid chain based on site-directed mutagenesis. The resulting recombinant protein, azurin, retained its original redox property in the same manner as native azurin. Recombinant azurin was immobilized on Au substrate by strong affinity between thiol of cysteine and gold. The orientations of recombinant azurin with various cysteine residues immobilized on the Au substrate were analyzed by fluorescence microscope, scanning tunneling microscope, and surface plasmon resonance. Our data revealed that binding activity of recombinant azurin with three cysteine residues on the Au substrate significantly increased in comparison to single residue azurin. Immobilization method of highly oriented recombinant azurin based on cysteine-modification could be useful for the nanoscale film fabrication of nanobiochip.

Fabrication of nano scaled protein monolayer consisting of cytochrome c on self-assembled 11-MUA layer for bioelectronic device.

The biomolecular/organic hetero-structure films (cytochrome c/11-mercapto-undecanoic acid) on gold substrates were controlled and fabricated with molecular level for developing valuable molecular electronic devices. Cytochrome c is a metalloprotein having redox property, which can be directly applicable to biomemory device as a active element. For efficient immobilization of the protein on the gold substrate, 11-mercapto-undecanoic acid (11-MUA) was used as a linker material between protein and inorganic substrate. The proposed nano scaled biomolecular/organic hetero-structure layer (cytochrome c/11-MUA) on gold surface was investigated by using surface plasmon resonance technique. The molecular morphology of the fabricated protein layer was confirmed by scanning tunneling microscopy. Electrochemical properties of fabricated biomolecular/organic hetero layer were verified using cyclic voltammetry. Their redox properties was sustained over 1000 cycles of cyclic voltametry. It proved that the fabricated film was a suitable platform for the bioelectronic device application.

Repair of osteochondral defects with a construct of mesenchymal stem cells and a polydioxanone/poly(vinyl alcohol) scaffold.

The purpose of the present study was to test the potential of an MSC (mesenchymal stem cell)/PDO/PVA [polydioxanone/poly(vinyl alcohol)] hybrid scaffold construct to repair cartilage defects. For the in vitro study, MSCs were isolated from human bone marrow and cultured in PDO/PVA scaffolds for 4 weeks. Gross and microscopic examinations were performed, as well as RT-PCR (reverse-transcription PCR) analyses for cartilage-specific genes. For the in vivo study, MSCs isolated from rabbits were cultured in the PDO/PVA scaffolds and tissue-engineered into neocartilage, then implanted into the osteochondral defect on the distal femur of the same rabbits. Gross and histological evaluations were performed at 8 weeks after the implantation. The results of the in vitro study demonstrated that the physical stability of the cell-cultured hybrid scaffold was maintained until 4 weeks after initial placement. Scanning electronmicroscopy indicated the infiltration of the cells into, and appropriate interactions with, the scaffolds. RT-PCR showed an expression of cartilage-specific genes similar to that seen with pellet-cultured MSCs. From the in vivo study, the defect area of the experimental group showed smooth consistent glistening white tissue resembling articular cartilage, whereas the control group showed a red irregular tissue with surface depression. The regenerated cartilage of the experimental group showed metachromasia on both Safranin-O and dense staining for type II collagen, whereas the control group showed little metachromatic staining and less intense staining for type II collagen. A histological score of the quality of cartilage formation indicated that the MSC/PDO/PVA hybrid scaffold successfully produced neocartilage in vitro and enhanced the repair of the osteochondral defect in vivo. Further in vivo studies will be necessary to elucidate further the value of PDO/PVA as a scaffold material for cartilage regeneration.

Biotechnological production of aromatic compounds of the extended shikimate pathway from renewable biomass.

Aromatic chemicals that contain an unsaturated ring with alternating double and single bonds find numerous applications in a wide range of industries, e.g. paper and dye manufacture, as fuel additives, electrical insulation, resins, pharmaceuticals, agrochemicals, in food, feed and cosmetics. Their chemical production is based on petroleum (BTX; benzene, toluene, and xylene), but they can also be obtained from plants by extraction. Due to petroleum depletion, health compliance, or environmental issues such as global warming, the biotechnological production of aromatics from renewable biomass came more and more into focus. Lignin, a complex polymeric aromatic molecule itself, is a natural source of aromatic compounds. Many microorganisms are able to catabolize a plethora of aromatic compounds and interception of these pathways may lead to the biotechnological production of value-added aromatic compounds which will be discussed for Corynebacterium glutamicum. Biosynthesis of aromatic amino acids not only gives rise to l-tryptophan, L-tyrosine and l-phenylalanine, but also to aromatic intermediates such as dehydroshikimate or chorismate from which value-added aromatic compounds can be derived. In this review, we will summarize recent strategies for the biotechnological production of aromatic and related compounds from renewable biomass by Escherichia coli, Pseudomonas putida, C. glutamicum and Saccharomyces cerevisiae. In particular, we will focus on metabolic engineering of the extended shikimate pathway.

General and programmable synthesis of hybrid liposome/metal nanoparticles.

Hybrid liposome/metal nanoparticles are promising candidate materials for biomedical applications. However, the poor selectivity and low yield of the desired hybrid during synthesis pose a challenge. We designed a programmable liposome by selective encoding of a reducing agent, which allows self-crystallization of metal nanoparticles within the liposome to produce stable liposome/metal nanoparticles alone. We synthesized seven types of liposome/monometallic and more complex liposome/bimetallic hybrids. The resulting nanoparticles are tunable in size and metal composition, and their surface plasmon resonance bands are controllable in visible and near infrared. Owing to outer lipid bilayer, our liposome/Au nanoparticle shows better colloidal stability in biologically relevant solutions as well as higher endocytosis efficiency than gold nanoparticles without the liposome. We used this hybrid in intracellular imaging of living cells via surface-enhanced Raman spectroscopy, taking advantage of its improved physicochemical properties. We believe that our method greatly increases the utility of metal nanoparticles in in vivo applications.

Human umbilical cord blood-derived CD34-positive endothelial progenitor cells stimulate osteoblastic differentiation of cultured human periosteal-derived osteoblasts.

The aim of this study was to examine the effects of human umbilical cord blood-derived CD34-positive endothelial progenitor cells (CD34+ EPCs) on osteoblastic differentiation of cultured human periosteal-derived osteoblasts (POs). CD34+ cells from human umbilical cord blood were sorted to purify more EPCs in characterization. These sorted cells showed CD31, VE-cadherin, and KDR expression as well as CD34 expression and formed typical tubes in Matrigel. These sorted cells were referred to as human cord blood-derived CD34+ EPCs. In in vivo bone formation using a miniature pig model, the newly formed bone was clearly examined in defects filled with polydioxanone/pluronic F127 (PDO/Pluronic F127) scaffolds containing either human umbilical cord blood-derived CD34+ EPCs and POs or human umbilical vein endothelial cells (HUVEC) and POs; however, the new bone had the greatest density in the defect treated with CD34+ EPCs and POs. Osteoblastic phenotypes of cultured human POs using ALP activity and von Kossa staining were also more clearly found in CD34+ EPC-conditioned medium than CD34-negative (CD34-) cell-conditioned medium, whereas HUVEC-conditioned medium had an intermediate effect. PCR array for common cytokines and growth factors showed that the secretion of interleukin (IL)-1ß was significantly higher in CD34+ EPCs than in HUVEC, followed by level in CD34- cells. In addition, IL-1ß also potently and dose dependently increased ALP activity and mineralization of POs in culture. These results suggest that human umbilical cord blood-derived CD34+ EPCs stimulates osteoblastic differentiation of cultured human POs. The functional role of human umbilical cord blood-derived CD34+ EPCs in increasing the osteogenic phenotypes of cultured human POs may depend on IL-1ß secreted from human umbilical cord blood-derived CD34+ EPCs.

Self-assembly of interfacial and photoactive layers via one-step solution processing for efficient inverted organic solar cells.

Vertically self-assembled bilayers with an interfacial bottom layer and a photoactive top layer are demonstrated via a single coating step of a blend composed of an amine-containing nonconjugated polyelectrolyte (NPE) and an organic electron donor-acceptor bulk heterojunction composite. The self-assembled NPE layer reduces the work function of an indium tin oxide (ITO) cathode, which leads to efficient inverted organic solar cells without any additional interface engineering of the ITO.

A population-based case-crossover study of polyethylene glycol use and acute renal failure risk in the elderly.

AIM: To evaluate the possibility of an association between polyethylene glycol (PEG) and acute renal failure (ARF) in elderly patients using a health insurance claims database. METHODS: We conducted a population-based case-crossover study using information obtained from Korean Health Insurance Review and Assessment Service (HIRA) claims from January 1, 2005 to December 31, 2005 (Seoul, Korea). The study population consisted of elderly patients who received PEG prior to experiencing their first ARF-related hospitalization from April 1, 2005 to December 31, 2005. For each patient, one case and two control periods were matched. PEG use in a 2- or 4-wk window period prior to hospitalization for ARF was compared with PEG use in two earlier 2- or 4-wk control window periods. Conditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% CI, adjusting for concomitant uses of diuretics, angiotensin converting enzyme inhibitors, non-steroidal anti-inflammatory drugs, antibiotics, anti-cancer drugs, and contrast media. RESULTS: Within the HIRA database which contained 1,093,262 elderly patients, 1156 hospitalized ARF cases were identified. Among these cases, PEG was prescribed to 17 (1.5%) patients before hospitalization. The adjusted ORs when applying the 2- and 4-wk window periods were 0.4 (95% CI: 0.03-5.24) and 2.1 (95% CI: 0.16-27.78), respectively. CONCLUSION: No increased risk of ARF was found in elderly PEG users. However, based on the limited number of study subjects, further analysis should be performed to confirm these results.

Tissue-engineered bone formation using periosteal-derived cells and polydioxanone/pluronic F127 scaffold with pre-seeded adipose tissue-derived CD146 positive endothelial-like cells.

The aim of this study was to generate tissue-engineered bone formation using periosteal-derived cells seeded into a polydioxanone/pluronic F127 (PDO/Pluronic F127) scaffold with adipose tissue-derived CD146 positive endothelial-like cells. Considering the hematopoietic and mesenchymal phenotypes of adipose tissue-derived cells cultured in EBM-2 medium, CD146 positive adipose tissue-derived cells was sorted to purify more endothelial cells in characterization. These sorted cells were referred to as adipose tissue-derived CD146 positive endothelial-like cells. Periosteum is a good source of osteogenic cells for tissue-engineered bone formation. Periosteal-derived cells were found to have good osteogenic capacity in a PDO/Pluronic F127 scaffold, which could provide a suitable environment for the osteoblastic differentiation of these cells. Through the investigation of capillary-like tube formation on matrigel and the cellular proliferation of adipose tissue-derived CD146 positive endothelial-like cells cultured in different media conditions, we examined these cells could be cultured in EBM-2 with osteogenic induction factors. We also observed that the osteogenic activity of periosteal-derived cells could be good in EBM-2 with osteogenic induction factors, in the early period of culture. The experimental results obtained in the miniature pig model suggest that tissue-engineered bone formation using periosteal-derived cells and PDO/Pluronic F127 scaffold with pre-seeded adipose tissue-derived CD146 positive endothelial-like cells can be used to restore the bony defects of the maxillofacial region when used in clinics.

Chondrogenesis using mesenchymal stem cells and PCL scaffolds.

We tested the in vitro feasibility of porous PCL (poly(epsilon-caprolactone)) as a scaffold for cartilage tissue engineering from mesenchymal stem cells (MSCs) and determined the effects of various surface treatments. Three porous PCL scaffold modifications were examined: (1) PCL/Pluronic F127, (2) PCL/collagen, and (3) PCL/Pluronic F127/collagen, in addition to (4) PCL-only. MSCs (5 x 10(5)) were seeded in PCL scaffolds of pore size 100-150 microm, and after 3 weeks of in vitro culture, MSC-scaffolds were investigated for gross appearance, DNA amount, glycosaminoglycan (GAG) content, chondrogenic gene expression, and histology. Grossly, the cell-scaffold complexes became harder, and were more easily manipulated with a forceps after 3 weeks of culture. The three surface-treated scaffolds had higher DNA contents than did the PCL-only scaffold, and the GAG contents in PCL/collagen and PCL/F127/collagen scaffolds were higher than those seen in the PCL-only scaffold. Real-time PCR showed that Sox-9 and COL2A1 mRNA levels were remarkably elevated in PCL/collagen and PCL/F127/collagen scaffolds versus the PCL-only scaffold. On the other hand, Col1A1 and Col10A1 mRNA levels were lower in the three modified PCL scaffolds than in the PCL-only scaffold. Histological findings generally concurred with GAG and RT-PCR findings, and demonstrated the affinity of PCL-based scaffolds for MSCs and the potentials of these scaffold to induce chondrogenic differentiation. Cells showed more differentiated appearance and more abundant extracellular matrix formation in PCL/collagen and PCL/collagen/F127 scaffolds. Our findings suggest that PCL-based porous scaffolds may be useful carriers for MSC transplantation in the cartilage tissue engineering field, and that collagen-based surface modifications further enhance the chondrogenic differentiation of MSCs.