Search

Background: Methylated resveratrol analogs show similar biological activities that are comparable with those of the resveratrol. However, the methylated resveratrol analogs exhibit better bioavailability as they are more easily transported into the cell and more resistant to degradation. Although these compounds are widely used in human health care and in industrial materials, at present they are mainly obtained by extraction from raw plant sources. Accordingly their production can suffer from a variety of economic problems, including low levels of productivity and/or heterogeneous quality. On this backdrop, large-scale production of plant metabolites via microbial approaches is a promising alternative to chemical synthesis and extraction from plant sources. Results: An Escherichia coli system containing an artificial biosynthetic pathway that produces methylated resveratrol analogues, such as pinostilbene (3,4’-dihydroxy-5-methoxystilbene), 3,5-dihydroxy-4’-methoxystilbene, 3,4’-dimethoxy-5-hydroxystilbene, and 3,5,4’-trimethoxystilbene, from simple carbon sources is developed. These artificial biosynthetic pathways contain a series of codon-optimized O-methyltransferase genes from sorghum in addition to the resveratrol biosynthetic genes. The E. coli cells that harbor pET-opTLO1S or pET-opTLO3S produce the one-methyl resveratrol analogues of 3,5-dihydroxy-4’-methoxystilbene and pinostilbene, respectively. Furthermore, the E. coli cells that harbor pET-opTLO13S produce 3,5-dihydroxy-4’-methoxystilbene, bis-methyl resveratrol (3,4’-dimethoxy-5-hydroxystilbene), and tri-methyl resveratrol (3,5,4’-trimethoxystilbene). Conclusions: Our strategy demonstrates the first harness microorganisms for de novo synthesis of methylated resveratrol analogs used a single vector system joined with resveratrol biosynthetic genes and sorghum two resveratrol O-methyltransferase genes. Thus, this is also the first report on the production of the methylated resveratrol compounds bis-methyl and tri-methyl resveratrol (3,4’-dimethoxy-5-hydroxystilbene and 3,5,4’-trimethoxystilbene) in the E. coli culture. Thus, the production of the methylated resveratrol compounds was performed on the simple E. coli medium without precursor feeding in the culture. [ABSTRACT FROM AUTHOR]

In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher's method. Penicillinolide A (1) inhibited the production of NO and PGE2 due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-a, IL-1ß and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of I?B-a, NF-?B nuclear translocation, and NF-?B DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-?B DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation. [ABSTRACT FROM AUTHOR]

STK295900, a small synthetic molecule belonging to a class of symmetric bibenzimidazoles, exhibits antiproliferative activity against various human cancer cell lines from different origins. Examining the effect of STK295900 in HeLa cells indicates that it induces G2 phase arrest without invoking DNA damage. Further analysis shows that STK295900 inhibits DNA relaxation that is mediated by topoisomerase 1 (Top 1) and topoisomerase 2 (Top 2) in vitro. In addition, STK295900 also exhibits protective effect against DNA damage induced by camptothecin. However, STK295900 does not affect etoposide-induced DNA damage. Moreover, STK295900 preferentially exerts cytotoxic effect on cancer cell lines while camptothecin, etoposide, and Hoechst 33342 affected both cancer and normal cells. Therefore, STK295900 has a potential to be developed as an anticancer chemotherapeutic agent. [ABSTRACT FROM AUTHOR]

Geldanamycin (GM) is a naturally occurring anticancer agent isolated from several strains of Streptomyces hygroscopicus. However, its potential clinical utility is compromised by its severe toxicity and poor water solubility. For this reason, considerable efforts are under way to make new derivatives that have both good clinical efficacy and high water solubility. On the other hand, glycosylation is often a step that improves the water solubility and/or biological activity in many natural products of biosynthesis. Here, we report the facile production of glucose-conjugated nonbenzoquinone GM analogs using the Bacillus UDP-glycosyl-transferase BL-C. Five aglycon substrates containing nonbenzoquinone aromatic rings were chosen to validate the in vitro glycosylation reaction. Putative glucoside compounds were determined through the presence of a product peak(s) and were also verified using LC/MS analyses. Further, the chemical structures of new glucoside compounds 6 and 7 were elucidated using spectroscopy data. These glucoside compounds showed a dramatic improvement in water solubility compared with that of the original aglycon, nonbenzoquinone GM. [ABSTRACT FROM AUTHOR]

The article discusses a study which determined the function of violaceol-I and -II in inducing the elongation of cell shape through F-actin aggregation. Researchers noted that the key features of elongation function by violaceol compounds are the presence of 2,2'-dihydroxy groups in the biphenyl system and calcium ions. The study concluded that the study of violaceol function can help in developing new antitumor drugs.

The effect of deposition temperature and post deposition annealing (PDA) on the electrical properties of HfO2 films grown on a Ge substrate by atomic layer deposition (ALD) was investigated. The HfO2 films deposited at 280°C (280°C-HfO2) showed a large capacitance-voltage (C-V) hysteresis, but it was significantly reduced at 200°C (200°C-HfO2). Further reduction of deposition temperature to 160°C resulted in the abrupt increase of C-V hysteresis. The reduction of C-V hysteresis was originated from the smaller degree of intermixing between the HfO2 and Ge substrate with decreasing temperature, while the increase of C-V hysteresis comes from the low density of films grown at low temperatures. The C-V hysteresis characteristics were also strongly influenced by PDA temperatures. PDA temperatures higher than 550°C induced a large C-V hysteresis regardless of deposition temperature. Interestingly, after the PDA process, the HfO2 grown at 200°C is crystallized to the tetragonal phase, while the HfO2 grown at 280°C is crystallized to the monoclinic phase. These different crystalline phases result in a lower equivalent oxide thickness in the 200°C-HfO2 compared to the 280°C-HfO2 [ABSTRACT FROM AUTHOR]

This paper proposes novel stripline models including embedded pores and sharpened conductor edges, which are commonly introduced during the multilayer low-temperature cofired-ceramic (LTCC) process. This model enables designers to obtain conductivity and tan δ of the stripline that are difficult to obtain using the experimental methods from arbitrary frequencies. This paper confirms that the proposed models are appropriate for LTCC striplines by comparing the simulated results with the experimental results. We found that embedded pores contributed to increase in unloaded quality factor (Qu) and characteristic impedance in the range of 5 % to 6 % while effective ϵr decreased in the range of 11%. Sharpened edges contributed to maximum peak in Qu and decreased characteristic impedance. These models will contribute to precision design of the future LTCC striplines. [ABSTRACT FROM AUTHOR]

The article discusses the results of the study of the manufacturing and foaming of high melt viscosity of polypropylene by using electron beam radiation technology. A description of the study design and methodology is given. The study showed the possibility of creating the high-melt-viscosity polypropylene at low radiation dosage and low monomer content. The study also revealed the effectiveness of 1,6-hexanediol diacrylate monomer for enhancing the melt viscosity of random ter-polypropylene.

A newly isolated marine bacterium, identified as Zoogloea sp., produced two different polysaccharides: one was water-soluble and the other was cell-bound. Both had non-Newtonian, pseudoplastic fluid behaviour and the solutions had low activation energies. The solutions of these polysaccharides showed rheological behaviour over a wide range of pH (2–12) and temperature (20–80 °C), and compatibility with NaCl. [ABSTRACT FROM AUTHOR]

An acinar morphogenesis inhibitor named fusarisetin A (1) that possesses both an unprecedented carbon skeleton and a new pentacycic ring system has been identified from an in-house fractionated fungal library using a three-dimensional matrigel-induced acinar morphogenesis assay system. The structure of was determined in detail by NMR and circular dichroism spectroscopy, X-ray analysis, and chemical reaction experiments. [ABSTRACT FROM AUTHOR]

Investigates the rheology and curing behavior of UV curable barium titanate suspensions. Influence of the Barium titanate particle size on cure depth; Development of the ferroelectric photoactive suspensions for stereolithography.

Investigates the effect of various stacking sequences of sol-gel-prepared Pb(Zr,Ti)O[sub 3]/PbZrO[sub 3] multilayered thin films on the electric fatigue properties. Antiferroelectric layer between the Pt electrode and the ferroelectric layers that acted as a barrier to fatigue; Leakage current of the multilayered films.

Abstract The effects of boiling water treatment on the physical properties of Quercus variabilis virgin cork (Qv VC) were examined and compared with those of Quercus suber reproduction cork (Qs RC). The water treatment was conducted at 100 °C for 1 h. Qv VC showed a significantly higher dimensional change in the three directions and lower weight loss than Qs RC by boiling water treatment. Untreated and boiled Qv VC showed higher density, air-dried moisture content, red/green (a*) and yellow/blue (b*) chromaticity, overall color change, shrinkage in all three directions, moisture adsorption on the entire surface, and swelling per 1% moisture content than untreated and boiled Qs RC. However, the lightness (L*) and water absorption on each surface were higher for Qs RC than for Qv VC. Moisture adsorption on each surface was comparable before and after heat treatment for both species. After boiling water treatment, the air-dried moisture content, dimensions, volume shrinkage, water absorption, and moisture adsorption on each surface and the entire surface increased, whereas L*, a*, b*, and swelling per 1% moisture content decreased. The results of the present study could be useful for further utilization of Qv cork growing in Korea.

Based on the sclereids in the bark of oak species, a convolutional neural network (CNN) was employed to validate species classification performance and its influencing factors. Three optimizers including stochastic gradient descent (SGD), adaptive moment estimation (Adam), root mean square propagation (RMSProp), and dataset augmentation were adopted. The accuracy and loss stabilized at approximately 15 to 20 and 70 to 80 epochs for the augmented and non-augmented condition, respectively. In the last five epochs, the RMSProp-augmented condition achieved the highest accuracy of 89.8%, whereas the Adam-augmented condition achieved the lowest accuracy of 73.8%. Regarding the loss, SGD-non-augmented condition was the lowest at 0.498, whereas Adamaugmented condition was the highest at 2.740. The highest accuracy was influenced by RMSProp at 0.194. Dataset augmentation had a significant influence on accuracy at 0.456. Homogeneous subsets among the validation conditions indicated that the accuracy and loss were classified into the same subset using an augmented dataset during the training, regardless of the optimizer. Only Adam and RMSProp with nonaugmented datasets were categorized into the same subset during the test. Hence, species classification using CNN and sclereid characteristics in the bark was feasible, and RMSProp with augmented datasets showed optimal performance for species classification. [ABSTRACT FROM AUTHOR]

Based on the sclereids in the bark of oak species, a convolutional neural network (CNN) was employed to validate species classification performance and its influencing factors. Three optimizers including stochastic gradient descent (SGD), adaptive moment estimation (Adam), root mean square propagation (RMSProp), and dataset augmentation were adopted. The accuracy and loss stabilized at approximately 15 to 20 and 70 to 80 epochs for the augmented and non-augmented condition, respectively. In the last five epochs, the RMSProp-augmented condition achieved the highest accuracy of 89.8%, whereas the Adam-augmented condition achieved the lowest accuracy of 73.8%. Regarding the loss, SGD-non-augmented condition was the lowest at 0.498, whereas Adam-augmented condition was the highest at 2.740. The highest accuracy was influenced by RMSProp at 0.194. Dataset augmentation had a significant influence on accuracy at 0.456. Homogeneous subsets among the validation conditions indicated that the accuracy and loss were classified into the same subset using an augmented dataset during the training, regardless of the optimizer. Only Adam and RMSProp with non-augmented datasets were categorized into the same subset during the test. Hence, species classification using CNN and sclereid characteristics in the bark was feasible, and RMSProp with augmented datasets showed optimal performance for species classification.

Background The number of cosmetic and reconstructive surgeries that use breast implants is increasing in Korea. Recently, it has been reported that breast implant-associated anaplastic large-cell lymphoma is related to textured breast implants, and interest in classification according to the texture of breast implants is increasing. However, there is currently no clear and unified classification. In particular, the definition of “microtextured” is highly varied. In this study, we retrospectively investigated and analyzed the clinical outcomes of smooth and microtextured breast implants. Methods A retrospective chart review of all patients who underwent breast augmentation surgery with smooth and microtextured silicone gel implants between January 2016 and July 2020 was performed. We retrospectively analyzed implant manufacturer, age, body mass index (BMI), smoking status, incision location, implant size, follow-up period, complications, and reoperation rate. Results A total of 266 patients underwent breast augmentation surgery, of which 181 used smooth silicone gel implants and 85 used microtextured silicone gel implants. Age, BMI, smoking status, implant size, and follow-up period were not significantly different between the two groups. Similarly, complications and reoperation rates were not significantly different between the two groups. Conclusion It is important to provide information regarding the clinical risks and benefits of breast implants to surgeons and patients through a clear and unified classification according to the texture of the breast implant.

To provide information on the identification and quality evaluation of Q. variabilis virgin cork from Korea, the qualitative anatomical characteristics of the virgin cork were observed by optical and scanning electron microscopy and compared with those of Q. suber reproduction cork from Portugal. Q. variabilis showed a narrower growth ring than Q. suber. A dark-brown zone with sclereids was found only in Q. variabilis cork. The lenticular channel in Q. variabilis is larger than that in Q. suber. Q. variabilis virgin cork showed a distinct growth ring boundary and an abrupt transition from earlycork to latecork with a few rows of latecork cells. Q. suber reproduction cork showed an indistinct growth ring with a gradual transition from one to two rows of latecork cells. In the earlycork, Q. suber showed mild corrugation, while Q. variabilis displayed significant corrugation with collapsed and distorted cork cells. The lenticular channel in Q. variabilis virgin cork was surrounded by thick-walled cells filled with compact lenticular filling tissue. Q. suber reproduction cork had an opening with loose lenticular filling tissue surrounded by thick-walled cells. Prismatic crystals, thick-walled sclereid cells, and fiber-sclereids were found only in Q. variabilis. A few trabeculae were found in both cork samples. [ABSTRACT FROM AUTHOR]

In this study, we found that chloroform fraction (CF) from TJP ethanolic extract inhibited lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and intracellular ROS in RAW264.7 cells. In addition, expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes was reduced, as evidenced by western blot. Our results indicate that CF exerts anti-inflammatory effects by down-regulating expression of iNOS and COX-2 genes through inhibition of MAPK (ERK, JNK and p38) and NF-κB signaling. Similarly we also evaluated the effects of CF on LPS-induced acute lung injury. Male Balb/c mice were pretreated with dexamethasone or CF 1 h before intranasal instillation of LPS. Eight hours after LPS administration, the inflammatory cells in the bronchoalveolar lavage fluid (BALF) were determined. The results indicated that CF inhibited LPS-induced TNF-α and IL-6 production in a dose dependent manner. It was also observed that CF attenuated LPS-induced lung histopathologic changes. In conclusion, these data demonstrate that the protective effect of CF on LPS-induced acute lung injury (ALI) in mice might relate to the suppression of excessive inflammatory responses in lung tissue. Thus, it can be suggested that CF might be a potential therapeutic agent for ALI. [ABSTRACT FROM AUTHOR]

Kearns-Sayre syndrome (KSS) is a rare multisystem mitochondrial disorder associated with progressive external ophthalmoplegia, atypical pigmentary degeneration of the retina, and complete heart block. KSS can lead to a risk of sudden death because of the potential progression of conduction abnormalities such as right or left bundle branch block or complete atrioventricular (AV) block. Here we describe the case of a KSS patient with type I diabetes who experienced syncope in the presence of complete AV block, confirmed by muscular biopsy.

Effects of treatment duration and clamping during heat treatment were evaluated relative to the color and physical and mechanical properties of okan wood. Sapwood and heartwood boards from okan wood were treated with and without clamping for 1 to 4 h at 180 °C. Changes in color were mostly due to a reduction in lightness (L*) and yellow/blue chromaticity (b*). These values decreased more for longer treatment durations. Red/green chromaticity (a*) was not affected by the treatment duration. Weight loss and volume shrinkage increased with increased treatment duration. Density only slightly decreased because of a balanced reduction in weight and volume. Clamping during treatment prevented surfaces from having direct contact with the heated air, which resulted in lower weight loss and volume shrinkage than in the samples treated without clamping. Heat-treated wood absorbed less water than the control group, as suggested by the lower equilibrium moisture content and water absorption. Furthermore, the heartwood absorbed less water than the sapwood. An evaluation of the mechanical properties showed a reduction in both the modulus of rupture and modulus of elasticity after heat treatment. Clamping minimized strength reduction in both sapwood and heartwood, particularly for 1 and 2 h heat treatments.

Pneumatosis cystoides intestinalis (PCI) is a rare condition characterized by multiple gas-filled cysts of varying size in the wall of gastrointestinal tract. PCI may idiopathic or secondary to various disorders. The etiology and pathogenesis of PCI are unclear. Treatment is usually conservative, and includes oxygen and antibiotics therapy. Surgery is reserved for cases of suspected inconvertible intestinal obstruction or perforation. Eleven patients who were diagnosed with PI between 2005 and 2015 were reviewed. We report three cases of PCI and describe causes and complications. The most important point in the treatment of PCI is to determine whether the patient needs surgery. Conservative care should be considered first if the patient is stable. If any complication is observed, such as ischemia in the intestine, surgery is needed. It is important to choose the best treatment based on prognostic factors and CT findings. (Korean J Gastroenterol 2016;67:262-266)

The objective was to evaluate the effect of temperature and clamping method during heat treatment on the properties of high density Okan wood. Heat treatment of sapwood and heartwood was conducted using an electric oven with a programmable controller at 160 °C, 180 °C, 200 °C, and 220 °C for 2 h. Physical and mechanical properties were compared before and after the heat treatment process. The color change (E*), weight loss, and volume shrinkage increased with increasing temperature, whereas the equilibrium moisture content (EMC) and water absorption (WA) decreased in both types of wood. The wood density was not affected by temperature, and the magnitude of E* in sapwood was the highest, while the magnitude of weight loss, volume shrinkage, EMC, and WA in heartwood was higher than in sapwood. The clamping method affected E* in heartwood only, while the weight loss, volume shrinkage, EMC, and WA was affect in both types of wood. A significant reduction in the mechanical properties occurred after heat treatment at 200 °C and 220 °C. The reduction of MOR, MOE, and shear strength in heartwood was greater than in sapwood, while the compressive strength reduction in sapwood was the highest.

Angiogenesis plays a very important role in tumor progression through the creation of new blood vessels. Therefore, angiogenesis inhibitors could contribute to cancer treatment. Here, we show that a microbial metabolite, elaiophylin, exhibits potent antiangiogenic activity from in vitro and in vivo angiogenesis assays. Elaiophylin dramatically suppressed in vitro angiogenic characteristics such as proliferation, migration, adhesion, invasion and tube formation of human umbilical vein endothelial cells (HUVECs) stimulated by vascular endothelial growth factor (VEGF) at non-toxic concentrations. In addition, elaiophylin immensely inhibited in vivo angiogenesis of the chorioallantoic membrane (CAM) from growing chick embryos without cytotoxicity. The activation of VEGF receptor 2 (VEGFR2) in HUVECs by VEGF was inhibited by elaiophylin, resulting in the suppression of VEGF-induced activation of downstream signaling molecules, Akt, extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38, nuclear factor-κB (NFκB), matrix metalloproteinase (MMP)-2 and -9 which are closely associated with VEGF-induced angiogenesis. We also found that elaiophylin blocked tumor cell-induced angiogenesis both in vitro and in vivo. Elaiophylin downregulated the expression of VEGF by inhibiting hypoxia inducible factor-1α (HIF-1α) accumulation in tumor cells. To our knowledge, these results for the first time demonstrate that elaiophylin effectively inhibits angiogenesis and thus may be utilized as a new class of natural antiangiogenic agent for cancer therapy. [ABSTRACT FROM AUTHOR]

Elevated expression of human enhancer filamentation 1 (HEF1; also known as NEDD9 or Cas-L) is an essential stimulus for the metastatic process of various solid tumors. This process requires HEF1 localization to focal adhesions (FAs). Although the association of HEF1 with FAs is considered to play a role in cancer cell migration, the mechanism targeting HEF1 to FAs remains unclear. Moreover, up-regulation of Polo-like kinase 1 (Plk1) positively correlates with human cancer metastasis, yet how Plk1 deregulation promotes metastasis remains elusive. Here, we report that casein kinase 1δ (CK1δ) phosphorylates HEF1 at Ser-780 and Thr-804 and that these phosphorylation events promote a physical interaction between Plk1 and HEF1. We found that this interaction is critical for HEF1 translocation to FAs and for inducing migration of HeLa cells. Plk1-docking phosphoepitopes were mapped/confirmed in HEF1 by various methods, including X-ray crystallography, and mutated for functional analysis in HeLa cells. In summary, our results reveal the role of a phosphorylation-dependent HEF1-Plk1 complex in HEF1 translocation to FAs to induce cell migration. Our findings provide critical mechanistic insights into the HEF1-Plk1 complex-dependent localization of HEF1 to FAs underlying the metastatic process and may therefore contribute to the development of new cancer therapies. [ABSTRACT FROM AUTHOR]

Chrysin (5,7-dihydroxyflavone), a natural flavonoid widely distributed in plants, reportedly has chemopreventive properties against various cancers. However, the anticancer activity of chrysin observed in in vivo studies has been disappointing. Here, we report that a chrysin derivative, referred to as compound 69407, more strongly inhibited EGF-induced neoplastic transformation of JB6 P+ cells compared with chrysin. It attenuated cell cycle progression of EGF-stimulated cells at the G1 phase and inhibited the G1/S transition. It caused loss of retinoblastoma phosphorylation at both Ser-795 and Ser-807/811, the preferred sites phosphorylated by Cdk4/6 and Cdk2, respectively. It also suppressed anchorage-dependent and -independent growth of A431 human epidermoid carcinoma cells. Compound 69407 reduced tumor growth in the A431 mouse xenograft model and retinoblastoma phosphorylation at Ser- 795 and Ser-807/811. Immunoprecipitation kinase assay results showed that compound 69407 attenuated endogenous Cdk4 and Cdk2 kinase activities in EGF-stimulated JB6 P+ cells. Pulldown and in vitro kinase assay results indicated that compound 69407 directly binds with Cdk2 and Cdk4 in an ATP-independent manner and inhibited their kinase activities. A binding model between compound 69407 and a crystal structure of Cdk2 predicted that compound 69407 was located inside the Cdk2 allosteric binding site. The binding was further verified by a point mutation binding assay. Overall results indicated that compound 69407 is an ATP-noncompetitive cyclin-dependent kinase inhibitor with anti-tumor effects, which acts by binding inside the Cdk2 allosteric pocket. This study provides new insights for creating a general pharmacophore model to design and develop novel ATP-noncompetitive agents with chemopreventive or chemotherapeutic potency. [ABSTRACT FROM AUTHOR]