Pilomatricoma on the Sole Following Wart Treatment.

Pilomatricoma is a benign skin tumor that arises from hair follicle stem cells. It typically presents in the facial region and rarely involves the palms and soles. A 15-year-old boy presented with a solitary tender nodule on the left sole. He had a history of plantar warts on the same site and had received multiple treatments including cryotherapy and intralesional bleomycin injection for nine months. Excisional biopsy was performed, and the specimen showed a well-demarcated mass in the deep dermis with basaloid cells undergoing abrupt keratinization. Ghost cells were seen with calcification. Based on these findings, he was diagnosed with pilomatricoma on the sole. We report a case of pilomatricoma, which developed on a site without hair follicles.

Comparative Study of Efficacy Between Cyclosporine and Alitretinoin in Patients With Chronic Hand Eczema.

Background: Systemic remedies such as cyclosporine, methotrexate, and retinoids are off-license treatment options that are considered for severe chronic hand eczema (CHE) that is resistant to first-line treatment. Objectives: The objective of this study was to determine the optimal treatment of CHE patients, including those with atopic dermatitis, and to compare the efficacy between cyclosporine and alitretinoin. Methods: This study was retrospective and included CHE patients who visited the Department of Dermatology at Hanyang University Seoul Hospital in Korea between March 2013 and February 2020. Results: A total of 95 CHE patients was included in this study. In the cyclosporine treatment group, there were more patients with severe baseline Investigator Global Assessment (IGA) (P = 0.033) and higher immunoglobulin E (IgE) level (P = 0.019). The mean recurrence duration was 15.9 weeks in the alitretinoin group and 22.9 weeks in the cyclosporine group, the difference between which was not statistically significant. In a subgroup analysis according to treatment drug, only the low IgE group showed a better recurrence profile for alitretinoin treatment compared to cyclosporine treatment (P = 0.039). When comparing the cumulative recurrence rate during the treatment period and subsequent follow-up periods, the cyclosporine group showed a greater incidence of recurrence than the alitretinoin group in all follow-up periods. The results of our study are consistent with the previously reported efficacy of alitretinoin. Despite the rapid response in the cyclosporine group, 12 weeks of CHE treatment with alitretinoin showed superior efficacy compared to cyclosporine treatment. Conclusions: Both alitretinoin and cyclosporine groups showed efficacy in patients with CHE. Cyclosporine is an alternative treatment of CHE that is refractory to alitretinoin or relapses after its use, especially in the presence of atopic dermatitis.

Changes in Respiratory Pathogens before and after the COVID-19 Pandemic (2018-2021).

Objective: This study is aimed at investigating the pattern of change occurring in respiratory pathogens before and after the outbreak of COVID-19, a type of viral pneumonia for which a pandemic was declared (March 2020). The results were analyzed by gender and age to identify the association between personal hygiene and prevention of infection by respiratory pathogens. Methods: A retrospective analysis was performed on 39,814 sputum, bronchial aspirate, and transtracheal aspirate samples obtained from 15,398 patients visiting a university hospital, located in Chungcheongnam-do, South Korea, between January 2018 and December 2021. From 4,454 patients whose samples were culture positive for bacteria, 6,389 strains were isolated and further cultured. Results: The mean age of the outpatients with respiratory pathogens was 66.2 years, and the comparison of the culture test results by gender showed that 64.9% (2,892/4,454) were male and 35.1% (1,562/4,454) were female. Compared to the pre-COVID-19 pandemic period, the number of outpatients with a request for respiratory microbial cultures after the onset of the pandemic was reduced by 20.7% and the number of outpatients with a positive culture result was reduced by 23.0%. The number of respiratory samples received was reduced by 6.7% after the pandemic, while the sample positive rate was reduced by 18.3%. Among the isolated microbial strains, there was a significant decrease of 43.1% for the Acinetobacter baumannii complex, 60.5% for Streptococcus pneumoniae, 67.2% for Haemophilus influenzae, and 78.1% for Moraxella catarrhalis when compared with pre-COVID-19 levels. The distribution of respiratory microbial strains by age group showed that the highest percentage of isolated strains was in patients in their 70s. Conclusions: The improvements in personal hygiene due to the COVID-19 pandemic exerted a substantial influence on the pattern of change in other common respiratory microorganisms, which highlights the importance of personal hygiene management in the prevention of respiratory infections.

Environment-Sensitive Ectodomain Shedding of Epithin/PRSS14 Increases Metastatic Potential of Breast Cancer Cells by Producing CCL2.

Epithin/PRSS14 is a membrane serine protease that plays a key role in tumor progression. The protease exists on the cell surface until its ectodomain shedding, which releases most of the extracellular domain. Previously, we showed that the remaining portion on the membrane undergoes intramembrane proteolysis, which results in the liberation of the intracellular domain and the intracellular domainmediated gene expression. In this study, we investigated how the intramembrane proteolysis for the nuclear function is initiated. We observed that ectodomain shedding of epithin/PRSS14 in mouse breast cancer 4T1 cells increased depending on environmental conditions and was positively correlated with invasiveness of the cells and their proinvasive cytokine production. We identified selenite as an environmental factor that can induce ectodomain shedding of the protease and increase C-C motif chemokine ligand 2 (CCL2) secretion in an epithin/PRSS14-dependent manner. Additionally, by demonstrating that the expression of the intracellular domain of epithin/PRSS14 is sufficient to induce CCL2 secretion, we established that epithin/PRSS14- dependent shedding and its subsequent intramembrane proteolysis are responsible for the metastatic conversion of 4T1 cells under these conditions. Consequently, we propose that epithin/PRSS14 can act as an environment-sensing receptor that promotes cancer metastasis by liberating the intracellular domain bearing transcriptional activity under conditions promoting ectodomain shedding.

Ex vivo expanded allogeneic natural killer cells have potent cytolytic activity against cancer cells through different receptor-ligand interactions.

BACKGROUND: Recently, allogeneic natural killer (NK) cells have gained considerable attention as promising immunotherapeutic tools due to their unique biological functions and characteristics. Although many NK expansion strategies have been reported previously, a deeper understanding of cryopreserved allogeneic NK cells is needed for specific therapeutic approaches. METHODS: We isolated CD3-CD56+ primary natural killer (pNK) cells from healthy donors and expanded them ex vivo using a GMP-compliant method without any feeder to generate large volumes of therapeutic pNK cells and cryopreserved stocks. After validation for high purity and activating phenotypes, we performed RNA sequencing of the expanded and cryopreserved pNK cells. The pNK cells were used against various cancer cell lines in 7-AAD/CFSE cytotoxicity assay. For in vivo efficacy study, NSG mice bearing subcutaneous cisplatin-resistant A2780cis xenografts were treated with our pNK cells or cisplatin. Antitumor efficacy was assessed by measuring tumor volume and weight. RESULTS: Compared to the pNK cells before expansion, pNK cells after expansion showed 2855 upregulated genes, including genes related to NK cell activation, cytotoxicity, chemokines, anti-apoptosis, and proliferation. Additionally, the pNK cells showed potent cytolytic activity against various cancer cell lines. Interestingly, our activated pNK cells showed a marked increase in NKp44 (1064-fold), CD40L (12,018-fold), and CCR5 (49-fold), and did not express the programmed cell death protein 1(PD-1). We also demonstrated the in vitro and in vivo efficacies of pNK cells against cisplatin-resistant A2780cis ovarian cancer cells having a high programmed death-ligand 1(PD-L1) and low HLA-C expression. CONCLUSIONS: Taken together, our study provides the first comprehensive genome wide analysis of ex vivo-expanded cryopreserved pNK cells. It also indicates the potential use of expanded and cryopreserved pNK cells as a highly promising immunotherapy for anti-cancer drug resistant patients.

Combined use of cisplatin plus natural killer cells overcomes immunoresistance of cisplatin resistant ovarian cancer.

Standard chemotherapy for ovarian cancers is often abrogated by drug resistance. Specifically, resistance to cisplatin is a major clinical obstacle to successful treatment of ovarian cancers. The aim of this study was to develop a therapeutic strategy using natural killer (NK) cells to treat cisplatin-resistant ovarian cancers. First, we compared the responses of ovarian cancer cell line A2780 and its cisplatin-resistant counterpart, A2780cis, to treatment with cisplatin plus NK92MI cells. Although combined treatment induces apoptosis of ovarian cancer cells via ROS-dependent and -independent mechanisms, A2780cis were resistant to NK92MI cell-mediated cytotoxicity. We found that A2780cis cells showed markedly higher expression of immune checkpoint protein, PD-L1, than the parental cells. Although pretreatment of A2780cis cells with cisplatin stimulated further expression of PD-L1, it also increased expression of ULBP ligands, which are activating receptors on NK92MI cells, both in vitro and in vivo. These findings suggest that combined use of cisplatin plus NK cell-mediated immunotherapy could overcome immunoresistance of chemoresistant ovarian cancers.

Intrinsic Magnetic Order of Chemically Exfoliated 2D Ruddlesden-Popper Organic-Inorganic Halide Perovskite Ultrathin Films.

Thin film fabrication of 2D layered organic-inorganic hybrid perovskites (2D-OIHPs) for spintronic applications has been attempted using solution-based process like Langmuir-Blodgett technique. However, monolayer or few-layered 2D magnets are not yet realized, even though a wide spectrum of 2D Ruddlesden-Popper (RP) OIHPs are known as quasi-2D Heisenberg magnets in bulk compounds. Here, chemical exfoliation by solvent engineering is applied to successfully synthesize large-sized, few unit-cell-thick 2D RP-OIHPs. Comprehensive structural characterization reveals that binary co-solvents with high relative polarity in spin coating technique are the most effective among nine kinds of solvents. Above all, this enables few-layered 2D RP-OIHP ultrathin films sustaining their intrinsic magnetic order. It is found that XY-like magnetic anisotropy driven by Jahn-Teller effect responsible for ferromagnetism in seven-layered (C6 H5 CH2 CH2 NH3 )2 CuCl4 ultrathin films remains very robust, whereas Ising-like dipolar anisotropy responsible for canted antiferromagnetism in ten-layered (C6 H5 CH2 CH2 NH3 )2 MnCl4 ultrathin films is greatly reduced. It is expected that ferromagnetism even at monolayer limit should be possible by means of further sophisticated solvent engineering as long as Jahn-Teller effect is active. The chemical exfoliation using solvent engineering unambiguously can bring about a new breakthrough in the development of 2D RP-OIHP van der Waals magnets for ultrahigh energy-efficient spintronic, opto-spintronic devices.

Critical Adjuvant Influences on Preventive Anti-Metastasis Vaccine Using a Structural Epitope Derived from Membrane Type Protease PRSS14.

We tested how adjuvants effect in a cancer vaccine model using an epitope derived from an autoactivation loop of membrane-type protease serine protease 14 (PRSS14; loop metavaccine) in mouse mammary tumor virus (MMTV)-polyoma middle tumor-antigen (PyMT) system and in 2 other orthotopic mouse systems. Earlier, we reported that loop metavaccine effectively prevented progression and metastasis regardless of adjuvant types and TH types of hosts in tail-vein injection systems. However, the loop metavaccine with Freund's complete adjuvant (CFA) reduced cancer progression and metastasis while that with alum, to our surprise, were adversely affected in 3 tumor bearing mouse models. The amounts of loop peptide specific antibodies inversely correlated with tumor burden and metastasis, meanwhile both TH1 and TH2 isotypes were present regardless of host type and adjuvant. Tumor infiltrating myeloid cells such as eosinophil, monocyte, and neutrophil were asymmetrically distributed among 2 adjuvant groups with loop metavaccine. Systemic expression profiling using the lymph nodes of the differentially immunized MMTV-PyMT mouse revealed that adjuvant types, as well as loop metavaccine can change the immune signatures. Specifically, loop metavaccine itself induces TH2 and TH17 responses but reduces TH1 and Treg responses regardless of adjuvant type, whereas CFA but not alum increased follicular TH response. Among the myeloid signatures, eosinophil was most distinct between CFA and alum. Survival analysis of breast cancer patients showed that eosinophil chemokines can be useful prognostic factors in PRSS14 positive patients. Based on these observations, we concluded that multiple immune parameters are to be considered when applying a vaccine strategy to cancer patients.

A JUN N-terminal kinase inhibitor induces ectodomain shedding of the cancer-associated membrane protease Prss14/epithin via protein kinase CßII.

Serine protease 14 (Prss14)/epithin is a transmembrane serine protease that plays essential roles in tumor progression and metastasis and therefore is a promising target for managing cancer. Prss14/epithin shedding may underlie its activity in cancer and worsen outcomes; accordingly, a detailed understanding of the molecular mechanisms in Prss14/epithin shedding may inform the design of future cancer therapies. On the basis of our previous observation that an activator of PKC, phorbol 12-myristate 13-acetate (PMA), induces Prss14/epithin shedding, here we further investigated the intracellular signaling pathway involved in this process. While using mitogen-activated protein kinase inhibitors to investigate possible effectors of downstream PKC signaling, we unexpectedly found that an inhibitor of c-Jun N-terminal kinase (JNK), SP600125, induces Prss14/epithin shedding even in the absence of PMA. SP600125-induced shedding, like that stimulated by PMA, was mediated by tumor necrosis factor-α-converting enzyme. In contrast, a JNK activator, anisomycin, partially abolished the effects of SP600125 on Prss14/epithin shedding. Moreover, the results from loss-of-function experiments with specific inhibitors, short hairpin RNA-mediated knockdown, and overexpression of dominant-negative PKCßII variants indicated that PKCßII is a major player in JNK inhibition- and PMA-mediated Prss14/epithin shedding. SP600125 increased phosphorylation of PKCßII and tumor necrosis factor-α-converting enzyme and induced their translocation into the plasma membrane. Finally, in vitro cell invasion experiments and bioinformatics analysis of data in The Cancer Genome Atlas breast cancer database revealed that JNK and PKCßII are important for Prss14/epithin-mediated cancer progression. These results provide important information regarding strategies against tumor metastasis.

Targeting metastatic breast cancer with peptide epitopes derived from autocatalytic loop of Prss14/ST14 membrane serine protease and with monoclonal antibodies.

BACKGROUND: In order to develop a new immunotherapeutic agent targeting metastatic breast cancers, we chose to utilize autocatalytic feature of the membrane serine protease Prss14/ST14, a specific prognosis marker for ER negative breast cancer as a target molecule. METHODS: The study was conducted using three mouse breast cancer models, 4 T1 and E0771 mouse breast cancer cells into their syngeneic hosts, and an MMTV-PyMT transgenic mouse strain was used. Prss14/ST14 knockdown cells were used to test function in tumor growth and metastasis, peptides derived from the autocatalytic loop for activation were tested as preventive metastasis vaccine, and monoclonal and humanized antibodies to the same epitope were tested as new therapeutic candidates. ELISA, immunoprecipitation, Immunofluorescent staining, and flow cytometry were used to examine antigen binding. The functions of antibodies were tested in vitro for cell migration and in vivo for tumor growth and metastasis. RESULTS: Prss14/ST14 is critically involved in the metastasis of breast cancer and poor survival rather than primary tumor growth in two mouse models. The epitopes derived from the specific autocatalytic loop region of Prss14/ST14, based on structural modeling acted as efficient preventive metastasis vaccines in mice. A new specific monoclonal antibody mAb3F3 generated against the engineered loop structure could reduce cell migration, eliminate metastasis in PyMT mice, and can detect the Prss14/ST14 protein expressed in various human cancer cells. Humanized antibody huAb3F3 maintained the specificity and reduced the migration of human breast cancer cells in vitro. CONCLUSION: Our study demonstrates that Prss14/ST14 is an important target for modulating metastasis. Our newly developed hybridoma mAbs and humanized antibody can be further developed as new promising candidates for the use in diagnosis and in immunotherapy of human metastatic breast cancer.

Enhanced butyric acid production using mixed biomass of brown algae and rice straw by Clostridium tyrobutyricum ATCC25755.

A brown alga Saccharina japonica and rice straw are attractive feedstock for microbial butyric acid production. However, inefficient fermentation of mannitol (a dominant component in S. japonica) and toxicity of inhibitors in lignocellulosic hydrolysate are limitations. This study demonstrated that mixed biomass with S. japonica and rice straw was effective in butyric acid production over those restrictions. Mannitol was consumed only when acetic acid was present. Notably, acetic acid was not produced but consumed along with mannitol. By mixing S. japonica and rice straw to take advantage of glucose and acetic acid in rice straw, Clostridium tyrobutyricum effectively consumed mannitol by utilizing acetic acid in hydrolysate and acetic acid derived from glucose with the enhanced butyric acid production. Furthermore, cell growth was restored owing to the decreased inhibitor concentration. The results demonstrate the potential of butyric acid production from mixed biomass of macroalgae/lignocellulose overcoming the drawbacks of single biomass.

Solvent-dependent self-assembly of two dimensional layered perovskite (C6H5CH2CH2NH3)2MCl4 (M = Cu, Mn) thin films in ambient humidity.

Two dimensional layered organic-inorganic halide perovskites offer a wide variety of novel functionality such as solar cell and optoelectronics and magnetism. Self-assembly of these materials using solution process (ex. spin coating) makes crystalline thin films synthesized at ambient environment. However, flexibility of organic layer also poses a structure stability issue in perovskite thin films against environment factors (ex. moisture). In this study, we investigate the effect of solvents and moisture on structure and property in the (C6H5(CH2)2NH3)2(Cu, Mn)Cl4 (Cu-PEA, Mn-PEA) perovskite thin films spin-coated on Si wafer using three solvents (H2O, MeOH, MeOH + H2O). A combination of x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) show that relative humidity (RH) has a profound effect on perovskite thin films during sample synthesis and storage, depending on the kind of solvent used. The ones prepared using water (Cu-PEA:H2O, Mn-PEA:H2O) show quite different behavior from the other cases. According to time-dependent XRD, reversible crystalline-amorphous transition takes place depending on RH in the former cases, whereas the latter cases relatively remain stable. It also turns out from XAS that Mn-PEA thin films prepared with solvents such as MeOH and MeOH + H2O are disordered to the depth of about 4 nm from surface.

Aerobic and anaerobic cellulose utilization by Paenibacillus sp. CAA11 and enhancement of its cellulolytic ability by expressing a heterologous endoglucanase.

For cost-effective lignocellulosic biofuel/chemical production, consolidated bioprocessing (CBP)-enabling microorganisms utilizing cellulose as well as producing biofuel/chemical are required. A novel strain Paenibacillus sp. CAA11 isolated from sediment was found to be not only as a cellulose degrader under both aerobic and strict anaerobic conditions but also as a producer of cellulosic biofuel/chemicals. Paenibacillus sp. CAA11 secreted cellulolytic enzymes by its own secretion system and produced ethanol as well as short-chain organic acids (formic acid, acetic acid, lactic acid) from cellulose. Cellulolytic activity of the strain was significantly enhanced by expressing a heterologous endoglucanase 168Cel5 from Bacillus subtilis under both aerobic and anaerobic conditions. The strain harboring the 168cel5 gene revealed 2-fold bigger halo zone on Congo-red plate and 1.75-fold more aerobic cellulose utilization in liquid medium compared with the negative control. Notably, under anaerobic conditions, the recombinant strain expressing 168Cel5 consumed 1.83-fold more cellulose (5.10 g/L) and produced 5-fold more ethanol (0.65 g/L) along with 5-fold more total acids (1.6 g/L) compared with the control, resulting 2.73-fold higher yields. This result demonstrates the potential of Paenibacillus sp. CAA11 as a suitable aerobic and anaerobic CBP-enabling microbe with cellulolytic production of ethanol and short-chain organic acids.

Effective isopropanol-butanol (IB) fermentation with high butanol content using a newly isolated Clostridium sp. A1424.

BACKGROUND: Acetone-butanol-ethanol fermentation has been studied for butanol production. Alternatively, to achieve acetone-free butanol production, use of clostridium strains producing butanol and 1,3-propanediol (1,3-PDO) from glycerol, natural and engineered isopropanol-butanol-ethanol (IBE) producers has been attempted; however, residual 1,3-PDO and acetone, low IBE production by natural IBE producers, and complicated gene modification are limitations. RESULTS: Here, we report an effective isopropanol and butanol (IB) fermentation using a newly isolated Clostridium sp. A1424 capable of producing IB from various substrates with a small residual acetone. Notably, this strain also utilized glycerol and produced butanol and 1,3-PDO. After 46.35 g/L of glucose consumption at pH 5.5-controlled batch fermentation, Clostridium sp. A1424 produced 9.43 g/L of butanol and 13.92 g/L of IB at the productivity of 0.29 and 0.44 g/L/h, respectively, which are the highest values in glucose-based batch fermentations using natural IB producers. More interestingly, using glucose-glycerol mixtures at ratios ranging from 20:2 to 14:8 led to not only acetone-free and 1,3-PDO-free IB fermentation but also enhanced IB production along with a much higher butanol content (butanol/isopropanol ratio of 1.81 with glucose vs. 2.07-6.14 with glucose-glycerol mixture). Furthermore, when the mixture of glucose and crude glycerol at the ratio of 14:8 (total concentration of 35.68 g/L) was used, high butanol/isopropanol ratio (3.44) and butanol titer (9.86 g/L) were achieved with 1.4-fold enhanced butanol yield (0.28 g/g) and productivity (0.41 g/L/h) compared to those with glucose only at pH 5.5. CONCLUSIONS: A newly isolated Clostridium sp. A1424 was able to produce butanol and isopropanol from various carbon sources. The productivity and titer of butanol and total alcohol obtained in this study were higher than the previously reported results obtained using other natural IB producers. Use of the mixture of glucose and glycerol was successful to achieve acetone-free, 1,3-PDO-free, and enhanced IB production with higher yield, productivity, and selectivity of butanol compared to those with glucose only, providing great advantages from the perspective of carbon recovery to alcohols. This notable result could be accomplished by isolating an effective IB producer Clostridium sp. A1424 as well as by utilizing glucose-glycerol mixtures.

Factors determining long-term outcomes of hepatocellular carcinoma within the Milan criteria: liver transplantation versus locoregional therapy: A retrospective cohort study.

Patients with hepatocellular carcinoma (HCC) satisfying the Milan criteria are candidates for liver transplantation (LT), but locoregional therapies could be another options for them.A total of 1859 treatment-naïve HCC patients fulfilling the Milan criteria were analyzed. Survival tree analysis was performed to generate survival nodes with similar survival risks in 1729 non-LT group, and compared with the survival of 130 patients who received LT.Among patients who did not receive LT, survival tree analysis classified patients into 6 nodes according to Child-Pugh (CP) score, serum alphafetoprotein (AFP) levels, tumor size, and age, with different mortality risks (5-year survival rate of 87.3%, 77.5%, 65.8%, 64.7%, 44.0%, and 28.7% for nodes 1-6, respectively; P < 0.001). The overall survival of patients in nodes 1 (CP score 5 with AFP levels <5 ng/mL) and 2 (CP score 5 with maximal tumor size <2.5 cm) were comparable with that of patients who received LT (both P > 0.05), but the survival rates of patients in nodes 3 to 6 were worse than that of LT (P < 0.05 for all). In each survival node, survival differed slightly according to initial treatment modality for patients who did not receive LT. For patients who received LT, tumor stage at the time of LT was associated with long-term outcome.Certain groups of non-LT patients showed survival rates that were similar to the survival rates of LT patients. CP score, AFP levels, tumor size, and age were baseline factors that can help estimate the long-term outcomes of non-LT treatment. In addition, tumor stage at the time of LT and specific initial treatment modality in non-LT patients affected the long-term outcomes. These factors can help estimate the long-term outcomes of HCC patients diagnosed within the Milan criteria.

Butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1 with high butyric acid yield and selectivity.

The aim of this work was to study the butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1. Results showed that Clostridium sp. S1 produced butyric acid by simultaneously utilizing glucose and mannose in softwood hydrolysate and, more remarkably, it consumed acetic acid in hydrolysate. Clostridium sp. S1 utilized each of glucose, mannose, and xylose as well as mixed sugars simultaneously with partially repressed xylose utilization. When softwood (Japanese larch) hydrolysate containing glucose and mannose as the main sugars was used, Clostridium sp. S1 produced 21.17g/L butyric acid with the yield of 0.47g/g sugar and the selectivity of 1 (g butyric acid/g total acids) owing to the consumption of acetic acid in hydrolysate. The results demonstrate potential of Clostridium sp. S1 to produce butyric acid selectively and effectively from hydrolysate not only by utilizing mixed sugars simultaneously but also by converting acetic acid to butyric acid.

Antibiotic Resistance and Virulence Potentials of Shiga Toxin-Producing Escherichia coli Isolates from Raw Meats of Slaughterhouses and Retail Markets in Korea.

In this study, the prevalence of Shiga toxin-producing Escherichia coli (STEC) was investigated among raw meat or meat products from slaughterhouses and retail markets in South Korea, and their potential for antibiotic resistance and virulence was further analyzed. A total of 912 raw meats, including beef, pork, and chicken, were collected from 2008 to 2009. E. coli strains were frequently isolated in chicken meats (176/233, 75.9%), beef (102/217, 42.3%), and pork (109/235, 39.2%). Putative STEC isolates were further categorized, based on the presence or absence of the Shiga toxin (stx) genes, followed by standard O-serotyping. Polymerase chain reaction assays were used to detect the previously defined virulence genes in STEC, including Shiga toxins 1 and Shiga toxin 2 (stx1 and 2), enterohemolysin (ehxA), intimin (eaeA), STEC autoagglutination adhesion (saa), and subtilase cytotoxin (subAB). All carried both stx1 and eae genes, but none of them had the stx2, saa, or subAB genes. Six (50.0%) STEC isolates possessed the ehxA gene, which is known to be encoded by the 60-megadalton virulence plasmid. Our antibiogram profiling demonstrated that some STEC strains, particularly pork and chicken isolates, displayed a multiple drug-resistance phenotype. RPLA analysis revealed that all the stx1-positive STEC isolates produced Stx1 only at the undetectable level. Altogether, these results imply that the locus of enterocyte and effacement (LEE)-positive strains STEC are predominant among raw meats or meat products from slaughterhouses or retail markets in Korea.

Butyric acid production from red algae by a newly isolated Clostridium sp. S1.

OBJECTIVE: To produce butyric acid from red algae such as Gelidium amansii in which galactose is a main carbohydrate, microorganisms utilizing galactose and tolerating inhibitors in hydrolysis including levulinic acid and 5-hydroxymethylfurfural (HMF) are required. RESULTS: A newly isolated bacterium, Clostridium sp. S1 produced butyric acid not only from galactose as the sole carbon source but also from a mixture of galactose and glucose through simultaneous utilization. Notably, Clostridium sp. S1 produced butyric acid and a small amount of acetic acid with the butyrate:acetate ratio of 45.4:1 and it even converted acetate to butyric acid. Clostridium sp. S1 tolerated 0.5-2 g levulinic acid/l and recovered from HMF inhibition at 0.6-2.5 g/l, resulting in 85-92% butyric acid concentration of the control culture. When acid-pretreated G. amansii hydrolysate was used, Clostridium sp. S1 produced 4.83 g butyric acid/l from 10 g galactose/l and 1 g glucose/l. CONCLUSION: Clostridium sp. S1 produces butyric acid from red algae due to its characteristics in sugar utilization and tolerance to inhibitors, demonstrating its advantage as a red algae-utilizing microorganism.

Expression Analyses Revealed Thymic Stromal Co-Transporter/Slc46A2 Is in Stem Cell Populations and Is a Putative Tumor Suppressor.

By combining conventional single cell analysis with flow cytometry and public database searches with bioinformatics tools, we extended the expression profiling of thymic stromal cotransporter (TSCOT), Slc46A2/Ly110, that was shown to be expressed in bipotent precursor and cortical thymic epithelial cells. Genome scale analysis verified TSCOT expression in thymic tissue- and cell type- specific fashion and is also expressed in some other epithelial tissues including skin and lung. Coexpression profiling with genes, Foxn1 and Hoxa3, revealed the role of TSCOT during the organogenesis. TSCOT expression was detected in all thymic epithelial cells (TECs), but not in the CD31(+) endothelial cell lineage in fetal thymus. In addition, ABC transporter-dependent side population and Sca-1(+) fetal TEC populations both contain TSCOT-expressing cells, indicating TEC stem cells express TSCOT. TSCOT expression was identified as early as in differentiating embryonic stem cells. TSCOT expression is not under the control of Foxn1 since TSCOT is present in the thymic rudiment of nude mice. By searching variations in the expression levels, TSCOT is positively associated with Grhl3 and Irf6. Cytokines such as IL1b, IL22 and IL24 are the potential regulators of the TSCOT expression. Surprisingly, we found TSCOT expression in the lung is diminished in lung cancers, suggesting TSCOT may be involved in the suppression of lung tumor development. Based on these results, a model for TEC differentiation from the stem cells was proposed in context of multiple epithelial organ formation.

Electrochemical detoxification of phenolic compounds in lignocellulosic hydrolysate for Clostridium fermentation.

Lignocellulosic biomass is being preferred as a feedstock in the biorefinery, but lignocellulosic hydrolysate usually contains inhibitors against microbial fermentation. Among these inhibitors, phenolics are highly toxic to butyric acid-producing and butanol-producing Clostridium even at a low concentration. Herein, we developed an electrochemical polymerization method to detoxify phenolic compounds in lignocellulosic hydrolysate for efficient Clostridium fermentation. After the electrochemical detoxification for 10h, 78%, 77%, 82%, and 94% of p-coumaric acid, ferulic acid, vanillin, and syringaldehyde were removed, respectively. Furthermore, 71% of total phenolics in rice straw hydrolysate were removed without any sugar-loss. Whereas the cell growth and metabolite production of Clostridium tyrobutyricum and Clostridium beijerinckii were completely inhibited in un-detoxified hydrolysate, those in detoxifying rice straw hydrolysate were recovered to 70-100% of the control cultures. The electrochemical detoxification method described herein provides an efficient strategy for producing butanol and butyric acid through Clostridium fermentation with lignocellulosic hydrolysate.