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Abstract: The purpose of this study is to empirically determine the relationship between employees’ constructs such as internal service quality, service ability, employee satisfaction, and organizational commitment, and customers’ constructs such as perceived value, customer satisfaction, customer trust, and loyalty. This relationship was studied by applying the Service Profit Chain model to the Korean restaurant industry. Results show that internal service quality has a significant effect on service ability, and teamwork/communication has a significant effect on employee satisfaction. Employees’ organizational commitment has a significant direct effect on the value perceived by customers. Ultimately, there is an indirect influential relationship between employees’ and customers’ constructs. Implications of these results are discussed, and possible limitations of the study are addressed. [Copyright &y& Elsevier]

Abstract: Mouse embryonic stem cells (mES cells), which are pluripotent and self-renewal cells, are derived from the inner cell mass of mouse blastocysts. The objective of this study was to construct more efficient mES cell-derived embryoid bodies (EBs) for use as a vasculogenesis model and as an in vitro vascular toxicity testing model. EBs were formed for 3 days using hanging drop cultures and plated on gelatin-coated plates in endothelial growth medium-2 (EGM-2) to promote vascular development. The differentiation of mES cell-derived EBs was confirmed by reverse transcription-polymerase chain reaction (RT-PCR), immunocytochemistry, and flow cytometry within 7 days after plating EBs. The mRNA and protein expressions of vascular endothelial growth factor receptors-2 (FLK-1), platelet endothelial cell adhesion molecule (PECAM), and vascular endothelial-cadherin (VE-cadherin) were observed in differentiated mES cells. When placed in matrigel, mES cell-derived endothelial like cells formed networks similar to vascular structures. mES cells were also exposed to 5-fluorouracil (5-FU), a strong inhibitor of vessel formation, and its cytotoxicity was determined using MTT assays. The inhibitory concentrations (IC50) of 5-FU for mES cells and C166 cells were 0.72μM and 1.04μM, respectively. These results demonstrate that mES cells can be used to study vasculogenesis and for cytotoxicity screening. [Copyright &y& Elsevier]

Chromosomal aberrations in 22 Koreans with ovarian carcinomas were investigated by degenerate oligonucleotide primed–polymerase chain reaction comparative genomic hybridization. The common sites of copy number increases were 20q (90%), 17q23∼qter (86%), 8q22∼qter (68%), 3q25∼qter (59%), 6p21 (59%), 11q13 (54%), 16p (40%), 2q31∼qter (36%), 7q (36%), 14q31 (36%), 15q24∼qter (36%), and 1q32∼qter (31%). DNA amplification was identified in 18 carcinomas (82%). The frequent sites of amplification were 20q13.2∼qter, 8q24.1, 17q23∼qter, 3q25∼qter, and 6p21. The most frequent sites of copy number decreases were 4q21∼q31 (54%), 5q13∼q21 (50%), and 13q14∼q21 (45%). The recurrent gains and losses of chromosomal regions identified in this study provide candidate regions that may contain oncogenes or tumor suppressor genes, respectively. [Copyright &y& Elsevier]

Hepatocellular carcinoma (HCC) is one of the most prevalent gastrointestinal malignant tumors in Southeast Asia. Thirty-one cirrhotic HCC, 14 noncirrhotic HCC, and 13 metastastic HCC in the Korean population were investigated on microdissected tissues for chromosomal aberrations by degenerate oligonucleotide–primed polymerase chain reaction (PCR) comparative genomic hybridization. A number of prominent sites of genomic imbalances were observed. The gains of 1q, 6p, 7, 8q, 12q, 13q31∼q32, 16p, 17q, and 20q and the losses of 1p, 4q, 6q, 8p, 9p, and 13q regions were observed with a similar high frequency in all types. Various chromosomal aberrations were observed preferentially to specific types. Gains of 4p15∼pter, 10q24∼qter, 18p11∼pter, and 19p10∼pter and a loss of 11q14∼q22 were observed in the cirrhotic HCC, whereas losses of 14q21∼q23 and 10q22∼q23 were observed in noncirrhotic HCC. In metastatic HCC, gains of 3q25∼qter and Xp21∼pter and losses of 21q11∼qter and Y were observed. The recurrent gains and losses of chromosomal regions identified in this study are consistent with several previous observations and provide possible candidate regions for the involvement of tumorigenesis and progressions of HCC. [Copyright &y& Elsevier]

Chromosomal aberrations were investigated in hepatitis B virus integrated into the hepatocellular carcinoma (HCC) cell lines SNU-368, SNU-449, SNU-398, SNU-182, and SNU-475 using Giemsa-banding, cross species color banding, and comparative genomic hybridization (CGH). The origins of the marker chromosomes were confirmed by fluorescence in situ hybridization with constructed chromosome painting probes. Each cell line had unique modal karyotypic characteristics and showed variable numbers of numerical and structural clonal cytogenetic aberrations. The gains were commonly detected on chromosome 1, and chromosome regions 6p, 7q, 8q, 10p, 17q, and 20; the losses were often found on 4q21∼qter, 13, 18q21∼qter, and Y. In particular, the breakpoints on 1p36, 1p13∼q21, 2p13∼q11, 6q10∼q11, 7q11, 7q22, 14q10, 16q10∼q13, 17q21, 18q21, and 19p11∼q11 were involved frequently at the multiple rearranged lesions. CGH analysis further confirmed the cytogenetic data, and the nonrandom rearrangements data suggested the candidate regions for the genes to be isolated which were related to HCC. [Copyright &y& Elsevier]

• Organizational identification and job satisfaction were positively correlated. • Job satisfaction was correlated with customer perceived value. • Customer perceived value was in turn correlated with customer satisfaction. • Positive service climate for employees can improve customer satisfaction. This study examines the interrelations between service climate, organizational identification, employee job satisfaction, and customer perceived value and satisfaction. To achieve this, we apply the service profit chain model to South Korea's coffee shop industry. Data were collected from 263 employees and 973 customers in Daegu. The hypotheses were tested by conducting a path analysis to investigate the relationship between the variables. Organizational identification and job satisfaction were found to be positively correlated with each other. Additionally, job satisfaction was correlated with customer perceived value, which, in turn, was correlated with customer satisfaction. The findings suggest that a good work environment and service-related training can create a positive service climate for employees, which can subsequently improve customer satisfaction. This study is unique in its application of the service profit chain model on the coffee shop industry in Korea. [ABSTRACT FROM AUTHOR]

In a previous study, we investigated the effects of high-temperature requirement factor A4 (HtrA4) deficiency on trophoblasts using the BeWo KO cell line. However, the effects of this deficiency on angiogenesis remain unclear. To explore the role of HtrA4 in angiogenesis, HUVECs were co-cultured with wild-type BeWo cells (BeWo WT), BeWo KO, and HtrA4 -rescued BeWo KO (BeWo KO- HtrA4 rescue) cells. Dil staining and dextran analysis revealed that HUVECs co-cultured with BeWo KO formed tubes, but they were often disjointed compared to those co-cultured with BeWo WT, BeWo KO- HtrA4 rescue, and HUVECs controls. RT-PCR, ELISA, and western blot analysis were performed to assess angiogenesis-related factors at the mRNA and protein levels. HtrA4 deficiency inhibited IL-6 expression in trophoblasts, and the reduced secretion of IL-6 decreases VEGFA expression in HUVECs by modulating the JAK2/STAT3 signaling pathway to prevent tube formation. Moreover, rescuing HtrA4 expression restored the HUVEC tube formation ability. Interestingly, IL-6 expression was lower in supernatants with only cultured HUVECs than in co-cultured HUVECs with BeWo WT cells, but the HUVEC tube formation ability was similar. These findings suggest that the promoting angiogenesis-related signaling pathway differs between only HUVECs and co-cultured HUVECs, and that the deficiency of HtrA4 weakens the activation of the IL-6/JAK/STAT3/VEGFA signaling pathway, reducing the ability of tube formation in HUVECs. HtrA4 deficiency in trophoblasts hinders angiogenesis and may contribute to placental dysfunction. [Display omitted] • HtrA4 deficiency suppresses IL-6 expression in BeWo cells. • Reduced IL-6 lowers VEGFA expression via modulating the JAK2/STAT3 signaling. • HtrA4 regulates the IL-6/JAK2/STAT3/VEGFA axis, influencing tube formation in HUVECs. [ABSTRACT FROM AUTHOR]

• MOTS-c promotes the morphology of aged hPD-MSCs. • MOTS-c activates AMPK and inhibits mTORC1. • MOTS-c enhances mitochondrial homeostasis. • MOTS-c reduces lipid synthesis. Mesenchymal stem cells (MSCs) are multipotent cells with critical roles in homeostasis and regeneration. MSCs undergo aging in response to various stresses, and this causes many diseases including degenerative disorders. Thus, regulation of aging factors is crucial for healthy aging. Mitochondrial open reading frame of the 12S rRNA-c (MOTS-c) was recently reported to regulate metabolic homeostasis. Here, we investigated the restorative effects of MOTS-c on aged human placenta-derived MSCs (hPD-MSCs). MOTS-c promoted the morphology of old hPD-MSCs. MOTS-c significantly activated AMP-activated protein kinase, which is the main target pathway of MOTS-c, and inhibited its antagonistic effector mTORC1. MOTS-c considerably enhanced mitochondrial homeostasis by decreasing oxygen consumption and reactive oxygen species production. The mitochondrial state of MOTS-c-treated old hPD-MSCs was more similar to that of young hPD-MSCs than the mitochondrial state of non-treated old hPD-MSCs. MOTS-c also decreased lipid synthesis. In conclusion, we demonstrated that MOTS-c promotes homeostasis in aged hPD-MSCs. [ABSTRACT FROM AUTHOR]

The gene MT3-MMP (also known as MMP16 ) encodes the membrane type 3 matrix metalloproteinase, which is a member of the matrix metalloproteinase ( MMP ) gene family. Several MMPs are associated with migration in colorectal cancer (CRC). However, the methylation status of the MT3-MMP promoter in CRC has not been reported. The methylation status and expression levels of MT3-MMP were investigated in primary tumor tissues and adjacent normal tissues in 105 patients with CRC, one normal colon cell line (CCD18Co), and three CRC cell lines (SW480, DLD-1, and LoVo) by quantitative methylation-specific PCR and real-time PCR. MT3-MMP was hypermethylated in 82 of 105 CRC tissues (78%), 30 of 105 adjacent normal tissues (29%), and two of 11 normal colon tissues (18%). MT3-MMP mRNA was significantly reduced in CRC compared with that in adjacent normal tissues ( P < 0.05). The methylation-mediated downregulation of MT3-MMP was restored by treatment with 5-aza-2′-deoxycytidine in two CRC cell lines, and MT3-MMP promoter activity was significantly reduced by methylation. The knockdown of MT3-MMP induced cell migration, but overexpressed MT3-MMP reduced cell migration in CRC cells. These results demonstrate that the MT3-MMP promoter is frequently hypermethylated in CRC and that downregulation of MT3-MMP may be important for cell migration in CRC. [ABSTRACT FROM AUTHOR]

Highlights: [•] We analyzed the effect of VCA on proliferation and invasion in trophoblast. [•] Cell proliferations of trophoblast were increased at low concentration of VCA. [•] Low concentration of VCA increases MMP-2 expression in trophoblast. [•] The expressions of integrin subunits α5 and β1 were increased at 10pg/ml of VCA. [•] VCA promotes invasion ability of trophoblast via the Akt signaling. [Copyright &y& Elsevier]

Abstract: Mesenchymal stem cells (MSCs) are powerful sources for cell therapy in regenerative medicine because they can be isolated from various tissues, expanded, and induced into multiple-lineages. Of note, their immunomodulatory effects maximize the therapeutic effects of stem cells engrafted on host, making them an especially attractive choice. Recently, several varieties of placenta-derived stem cells (PDSCs) including chorionic plate-derived MSCs (CP-MSCs) have been suggested as alternative sources of stem cells. However, comparative studies of immunomodulatory effects for CP-MSCs among various MSCs are largely lacking. We examined and compared immunomodulatory function of CP-MSCs with that of BM-MSCs and AD-MSCs using co-culture system with activated T-cells derived from human umbilical cord blood (UCB) exposed to anti-CD3 and anti-CD28 which are T-cell activating monoclonal antibodies. All MSCs expressed markers of stem cells and three germ layers by RT-PCR. These cells also exhibited comparable immunomodulatory effects when they were co-cultured with activated T-cells in dose-dependent manner. However, expression of HLA-ABC and HLA-G was highly positive in CP-MSCs compared to other MSCs, and higher levels of cytokines of IL-2, IL-4, IL-13, and GM-CSF were detected in dose-dependent manner in CP-MSCs. Taken together, the results of the present study suggest that while CP-MSCs, BM-MSCs, and AD-MSCs all have immunomodulatory effects, CP-MSCs may have additional advantage over the other MSCs in terms of immunomodulation. In conjunction with other previous studies, CP-MSCs are suggested to be a useful stem cell source in cell therapy. [Copyright &y& Elsevier]

Abstract: The human placenta is an organ for fetus development and abundant reservoir of various bioactive molecules. Interest to human placenta extract (hPE) is growing, and application with trial of hPE is widening in oriental medicine including in liver diseases. However, underlying mechanisms for therapeutic effects are still unclear. Here, we investigated therapeutic effects of hPE in carbon tetrachloride (CCl4)-injured rat liver model in vivo and in damaged rat hepatic cells exposed to CCl4 in vitro. In addition, regulation of inflammatory responses by treatment of hPE was investigated. Serum levels of GOT/AST and GPT/ALT were significantly reduced (P<0.05), and uptake/excretion of indocyanine green in serum was significantly induced at 3weeks after intravenous hPE administration in CCl4-injured rat model (P<0.05). Expression of type I collagen (Col I) and α-smooth muscle actin (α-SMA) was decreased, whereas that of matrix metalloproteinase-9 (MMP-9) was increased resulting in improvement of score for fibrotic grade in hPE group. Also, albumin, proliferation activities and molecules associated with liver regeneration (e.g. interleukin-6, gp130, ATP binding cassette transporters, cyclin A) were more increased in hPE administration group than Non-hPE group. hPE administration suppressed activated T-cell proliferation via increasing anti-inflammatory cytokines and decreasing pro-inflammatory cytokines. These results suggest that hPE could be effective for liver disease through reduction of fibrosis, induction of liver regeneration, and regulation of inflammatory responses. These findings are important for understanding the roles of hPE and provide evidences for therapeutic effects of hPE in hepatic diseases which could lead to potential clinical applications. [Copyright &y& Elsevier]

Abstract: Embryonic stem cells (ESCs) are known to characteristics for pluripotency and self-renewal, but the precise mechanisms of ES-derived cells to specific toxicants have not been determined. Here, we evaluated the cytotoxicity of 5-fluorouracil (5-FU) and see its effect on cell viability, proliferation, and differentiation in mouse ESC-derived endothelial differentiation. Mouse ESCs were exposed to 5-FU (10μM) and combined with probucol (50μM) for 24h, which is an antagonist of 5-FU. Changes in gene expression as a result of 5-FU exposure in mouse ESC-derived endothelial precursor cells (ES-EPCs) were assessed using an oligonucleotide microarray (AB1700). The expression of Oct-4 was decreased during the differentiation of mouse ESCs into endothelial cells; otherwise, the expression of PECAM was increased. Mouse ES-EPCs were shown to have a decrease in viability (49.8%) and PECAM expression, and induce G1/S phase (31.1%/60.6%) when compared with/without treatment of 5-FU. Expression of cell cycle-related proteins was increased in endothelial precursor cells exposed to 5-FU without probucol treatment. From theses results suggest that 5-FU inhibit endothelial differentiation as well as inducing the G1/S phase arrest. We propose that mouse ES-EPCs might be a useful tool for screening the cytotoxicity of compounds in endothelial cells. [Copyright &y& Elsevier]