Quantitative phase and refractive index imaging of 3D objects via optical transfer function reshaping.

Deconvolution phase microscopy enables high-contrast visualization of transparent samples through reconstructions of their transmitted phases or refractive indexes. Herein, we propose a method to extend 2D deconvolution phase microscopy to thick 3D samples. The refractive index distribution of a sample can be obtained at a specific axial plane by measuring only four intensity images obtained under optimized illumination patterns. Also, the optical phase delay of a sample can be measured using different illumination patterns.

A One-Stage Ensemble Framework Based on Convolutional Autoencoder for Remaining Useful Life Estimation.

As the legislative pressure to reduce energy consumption is increasing, data analysis of power consumption is critical in the production planning of manufacturing facilities. In legacy studies, a machine conducting a single continuous operation has been mainly observed for power estimation. However, the production machine of a modularized line, which conducts complex discrete operations, is more like the actual factory system than an identical simple machine. During the information collection of this kind of production line, it is important to interpret mixed signals from multiple machines to ensure that there is no reduction in the information quality due to noise and signal fusion and discrete events. A data pipeline-from data collection (from different sources) to preprocessing, data conversion, synchronization, and deep learning classification-to estimate the total power use of the future process plan, is proposed herein. The pipeline also establishes an auto-labeled data set of individual operations that contributes to building an power estimation model without manual data preprocessing. The proposed system is applied to a modular factory, connected with machine controllers, using standardized protocols individually and linked to a centralized power monitoring system. Specifically, a robot arm cell was investigated to evaluate the pipeline, with the result of the power profile being synchronized with the robot program.

Emergence of Huge Negative Spin-Transfer Torque in Atomically Thin Co layers.

Current-induced domain wall motion has drawn great attention in recent decades as the key operational principle of emerging magnetic memory devices. As the major driving force of the motion, the spin-orbit torque on chiral domain walls has been proposed and is currently extensively studied. However, we demonstrate here that there exists another driving force, which is larger than the spin-orbit torque in atomically thin Co films. Moreover, the direction of the present force is found to be the opposite of the prediction of the standard spin-transfer torque, resulting in the domain wall motion along the current direction. The symmetry of the force and its peculiar dependence on the domain wall structure suggest that the present force is, most likely, attributed to considerable enhancement of a negative nonadiabatic spin-transfer torque in ultranarrow domain walls. Careful measurements of the giant magnetoresistance manifest a negative spin polarization in the atomically thin Co films which might be responsible for the negative spin-transfer torque.

Analysis of the proficiency of single radial immunodiffusion assays for quality control of influenza vaccines in Korea.

Influenza vaccine potency, which is determined by quantitatively measuring the content of Hemagglutinin (HA), is an essential index representing the efficacy of the vaccine. Standardization of the single radial immunodiffusion (SRID) assay, a method for measuring HA content, and proficiency of the testing institutions are crucial for influenza vaccine quality control. Herein, we assessed the proficiency of SRID assays at the National Control Laboratory (NCL) of Korea and several vaccine manufacturers. Eight laboratories participated in this study, and the proficiencies of all laboratories yielded satisfactory results in overall SRID assays. In contrast, there were some unsatisfactory results in measuring with different types of agarose gel plates produced by other laboratories. Overall, our findings demonstrated that the proficiency of SRID assay in the tested laboratories is acceptable for quality control of influenza vaccines and that detailed review on the validation reports regarding the test methods will be helpful for better control.

Prognostic significance of microvascular invasion in tumor stage for hepatocellular carcinoma.

BACKGROUND: The presence of microvascular invasion (McVI) in hepatocellular carcinoma (HCC) has been proposed as a cause of recurrence and poor survival, although this has not been officially emphasized in staging systems. Thus, we conducted a retrospective study to investigate the prognostic importance of McVI in tumor staging in patients with HCC who underwent hepatic resection. METHODS: A retrospective analysis was performed of patients who underwent hepatic resection for HCC at our center from 1994 to 2012. Patients with HCC were classified into four groups based on the presence of McVI and extent of gross vascular invasion (VI). RESULTS: The 5-year overall and recurrence-free survival rates of 676 patients were 63.3 and 42.6%, respectively. There was no difference in tumor recurrence or survival rate between patients with HCC and McVI without gross VI and those with gross VI confined to segmental/sectional branches. Multivariate analysis revealed that the extent of VI based on the presence of McVI and gross VI was independently associated with tumor recurrence and overall survival. CONCLUSIONS: McVI was revealed to be an important risk factor similar to gross VI confined to a segmental/sectional branch in patients with HCC who underwent hepatic resection. This finding should be considered when estimating the stage for prognosis.

Effects of kinetic chain exercise using EMG-biofeedback on balance and lower extremity muscle activation in stroke patients.

[Purpose] The purpose of this study was to examine the effect of kinetic chain exercise using EMG-biofeedback on balance and lower extremity muscle activation. [Subjects and Methods] For this study, 30 stroke patients participated in this study and they were divided into closed kinetic chain exercise using EMG-biofeedback group (CKCE+EB) and open kinetic chain exercise using EMG-biofeedback group (OKCE+EB), each group consisting of 15 patients. The kinetic chain exercise using EMG-biofeedback was performed by the patients for 20 minutes once a day, 5 days a week, for 6 weeks using an Myo-Ex. BioRescue was used to measure balance ability, while surface EMG was used to measure the lower extremity muscle activation. [Results] According to the results of the comparison within the groups, after the intervention, both groups showed significant increases in the balance ability and lower extremity muscle activation. In the comparisons between the groups, after the intervention, balance ability and lower extremity muscle activation were significantly higher in the CKCE+BE than in the OKCE+EB. [Conclusion] This study showed that closed kinetic chain exercise using EMG-biofeedback is effective for improving balance ability and lower extremity muscle activation in stroke patients.

Mucosa-associated lymphoid tissue (MALT) lymphoma as an unusual cause of malignant hilar biliary stricture: a case report with literature review.

BACKGROUND: Biliary strictures at the hilum of the liver arise from heterogeneous etiologies. The majority is malignant entities, but some may have benign etiologies. It is difficult to distinguish between malignant and benign biliary strictures preoperatively. It has been reported that 5~15 % of preoperative diagnoses of hilar cholangiocarcinoma turn out to be benign lesions or even other types of malignancies. Primary non-Hodgkin's lymphoma of the extrahepatic bile duct is very rare, with only a few cases reported as mucosa-associated lymphoid tissue (MALT) lymphoma arising from the hepatic duct bifurcation. We herein report a case of a female patient presenting with perihilar bile ducts obstructed by primary MALT lymphoma resembling hilar cholangiocarcinoma, along with a review of the literature. CASE PRESENTATION: An 86-year-old female was referred to our hospital manifesting obstructive jaundice and abdominal pain. The reported imaging studies revealed distended intrahepatic bile duct with the stricture of common hepatic duct including bifurcation, which was suspicious of cholangiocarcinoma of the bile duct. The initial laboratory-confirmed cholestasis with a total bilirubin of 8.6 mg/dL, aspartate amino transferase (AST) 178 U/L, alanine transferase (ALT) 105 U/L, and the tumor marker CA 19-9 was elevated with a value of 167 U/mL. Viral markers for hepatitis B and C viruses were negative. She underwent extrahepatic bile duct resection and hepaticojejunostomy. Histological examination of the resected specimen revealed MALT lymphoma. Postoperative follow-up of 1 year has been completely uneventful, without any symptoms or disease recurrence. CONCLUSIONS: In exceptional cases, in which radiologic and clinical features point to cholangiocarcinoma, the actual reason for obstructive jaundice and abdominal pain can be a non-Hodgkin's lymphoma. In the case of a MALT lymphoma, it can be cured with complete resection.

Engineered Salmonella typhimurium expressing E7 fusion protein, derived from human papillomavirus, inhibits tumor growth in cervical tumor-bearing mice.

The tumor-suppressing effects of SipB160/HPV16 E7 fusion protein, derived from human papillomavirus, and expressed in Salmonella enterica serovar typhimurium, were evaluated in a cervical cancer model. The expressed E7 protein resulted in efficacious cytotoxicity and tumor growth retardation in TC-1 cervical cancer cells. In addition, in mice bearing TC-1 tumors, live cells of Salmonella expressing HPV16 E7 were administered orally and induced immune responses through interferon-gamma and tumor necrosis factor-alpha cytokine secretion and also suppressed tumor growth (45 %) and prolonged survival (70 %) compared with the control group. These results suggested that the SipB160/HPV16 E7 fusion protein may be a candidate cancer therapeutic agent.

RaoN, a small RNA encoded within Salmonella pathogenicity island-11, confers resistance to macrophage-induced stress.

Bacterial small non-coding RNAs act as important regulators that control numerous cellular processes. Here we identified RaoN, a novel small RNA encoded in the cspH-envE intergenic region on Salmonella pathogenicity island-11 (SPI-11). RaoN contributes to survival under conditions of acid and oxidative stress combined with nutrient limitation, which partially mimic the intramacrophage environment. Indeed, inactivation of raoN reduces the intramacrophage replication of Salmonella enterica serovar Typhimurium. Genome-wide transcriptome analysis revealed that the lactate dehydrogenase gene ldhA is upregulated in the raoN knockout mutant. Notably, both inactivation and overexpression of ldhA in the WT strain render Salmonella more sensitive to oxidative stress, particularly when combined with nutrient limitation. However, ldhA is not the sole determinant of RaoN function in facilitating intramacrophage survival of Salmonella. Together, our data suggest that balanced regulation of ldhA expression by RaoN is necessary for survival under in vitro stress conditions and contributes to the intramacrophage growth of Salmonella.

Molecular characterization of the InvE regulator in the secretion of type III secretion translocases in Salmonella enterica serovar Typhimurium.

The type III secretion systems (T3SSs) are exploited by many Gram-negative pathogenic bacteria to deliver a set of effector proteins into the host cytosol during cell entry. The T3SS of Salmonella enterica serovar Typhimurium is composed of more than 20 proteins that constitute the membrane-associated base, the needle and the tip complex at the distal end of the T3SS needle. Membrane docking and piercing between the T3SS and host cells is followed by the secretion of effector proteins. Therefore, a secretion hierarchy among the substrates of the T3SS is required. The secretion of the pore-forming translocase proteins SipB, SipC and SipD is controlled by the T3SS regulator protein, InvE. During an attempt to identify the regions of InvE that are involved in T3SS regulation, it was observed that the secretion of SipB, SipC and SipD was inhibited when the C-terminal 52 amino acids were removed from InvE. In addition, InvE derivatives lacking the N-terminal 30 and 100 residues were unable to secrete translocases into the culture medium. Interestingly, in the absence of the N-terminal 180 residues of InvE, SipD is unstable, resulting in the hypersecretion of SipB. We also found that both the type III secretion signals of SipB and SptP were functionally interchangeable with the first 30 amino acids of InvE, which could allow the secretion of a reporter protein. These results indicate that InvE may have two functional domains responsible for regulating the secretion of translocases: an N-terminal secretion signal and a C-terminal regulatory domain.

Polycyclic aromatic hydrocarbon (PAH)-mediated upregulation of hepatic microRNA-181 family promotes cancer cell migration by targeting MAPK phosphatase-5, regulating the activation of p38 MAPK.

Growing evidence indicates that changes in microRNA (miRNA) expression in cancer induced by chemical carcinogens play an important role in cancer development and progression by regulating related genes. However, the mechanisms underlying miRNA involvement in hepatocarcinogenesis induced by polycyclic aromatic hydrocarbons (PAHs) remain unclear. Thus, the identification of aberrant miRNA expression during PAH-induced cancer cell migration will lead to a better understanding of the substantial role of miRNAs in cancer progression. In the present study, miRNA expression profiling showed significant upregulation of miR-181a, -181b, and -181d in human hepatocellular carcinoma cells (HepG2 line) exposed to benzo[a]anthracene (BA) and benzo[k]fluoranthene (BF). MAPK phosphatase-5 (MKP-5), a validated miR-181 target that deactivates MAPKs, was markedly suppressed while phosphorylation of p38 MAPK was increased after BA and BF exposure. The migration of HepG2 cells, observed using the scratch wound-healing assay, also increased in a dose-dependent manner. Depletion of miR-181 family members by miRNA inhibitors enhanced the expression of MKP-5 and suppressed the phosphorylation of p38 MAPK. Furthermore, the depletion of the miR-181 family inhibited cancer cell migration. Based on these results, we conclude that the miR-181 family plays a critical role in PAH-induced hepatocarcinogenesis by targeting MKP-5, resulting in the regulation of p38 MAPK activation.

A multivalent peptide as an activator of hypoxia inducible factor-1α.

Hypoxia inducible factor-1α (HIF-1α) is a transcription factor found in mammalian cells under hypoxia. While HIF-1α in hypoxia translocates to the nucleus where it transcribes the target genes including vascular endothelial growth factor (VEGF) mRNA, HIF-1α is degraded under normoxia, which involves its proline hydroxylation and subsequent binding to the von Hippel-Lindau protein-Elongin B-Elogin C (VBC) complex. Previously, peptide inhibitors against this interaction between hydroxylated HIF-1α and VBC have been developed to stabilize the transcriptional activity of HIF-1α by preventing the degradation of the protein even under normoxia. Despite the specific inhibition by these peptides, their poor inhibition potency needs to be improved for further clinical application. In this work, we have designed and prepared a streptavidin-based multivalent peptide inhibitor against the HIF-1α-VBC complexation. We have evaluated the potency of the multivalent peptide in terms of stabilization of HIF-1α and the downstream effect. As the result, we have found that the inhibitor showed about 13-fold lowered IC50 value compared with that of the corresponding monovalent peptide, thereby activating HIF-1α and leading to up-regulation of VEGF protein at the cellular level.

Surgical outcomes of hepatocellular carcinoma with bile duct tumor thrombus: a Korean multicenter study.

BACKGROUND: The long-term outcomes after resection for hepatocellular carcinoma (HCC) with macroscopic bile duct tumor thrombus (BDTT) are unclear. This multicenter study was conducted to determine the prognosis of HCC patients with macroscopic BDTT who underwent resection with curative intent. METHODS: Of 4,308 patients with HCC from four Korean institutions, this single-arm retrospective study included 73 patients (1.7 %) who underwent resection for HCC with BDTT. RESULTS: Jaundice was also present in 34 patients (46.6 %). According to Ueda classification, BDTT was type 2 in 34 cases (46.6 %) and type 3 in 39 cases (53.4 %). Biliary decompression was performed in 33 patients (45.2 %), decreasing the median lowest bilirubin level to 1.4 mg/dL before surgery. Systematic hepatectomy was performed in 69 patients (94.5 %), and concurrent bile duct resection was performed in 31 patients (42.5 %). Surgical curability types were R0 (n = 57; 78.1 %), R1 (n = 11; 15.1 %), and R2 (n = 5; 6.8 %). Patient survival rates were 76.5 % at 1 year, 41.4 % at 3 years, 32.0 % at 5 years, and 17.0 % at 10 years. Recurrence rates were 42.9 % at 1 year, 70.6 % at 3 years, 77.3 % at 5 years, and 81.1 % at 10 years. Results of univariate survival analysis showed that maximal tumor size, bile duct resection, and surgical curability were significant risk factors for survival, and surgical curability was a significant risk factor for recurrence. Multivariate analysis did not reveal any independent risk factors. CONCLUSIONS: Hepatocellular carcinoma patients with BDTT achieved relatively favorable long-term results after resection; therefore extensive surgery should be recommended when complete resection is anticipated.

Effect of iacP mutation on flagellar phase variation in Salmonella enterica serovar typhimurium strain UK-1.

Flagella are surface appendages that are important for bacterial motility and invasion of host cells. Two flagellin subunits in Salmonella enterica serovar Typhimurium, FliC and FljB, are alternatively expressed by a site-specific DNA inversion mechanism called flagellar phase variation. Although this inversion mechanism is understood at the molecular level, the key factor controlling the expression of the two flagellin subunits has not been determined. In this study, we found that a putative acyl carrier protein, IacP, affects flagellar phase variation in S. Typhimurium strain UK-1 under Salmonella pathogenicity island 1 (SPI1)-inducing conditions. Liquid chromatography-mass spectrometry analysis of the secreted proteins from S. Typhimurium determined that the amount of FljB secreted was significantly higher in the iacP mutant strain, a finding confirmed by Western blot analysis. Northern blotting, quantitative PCR, and microarray data showed that the level of FljB in the iacP mutant strain was regulated at the transcriptional level, although the transcription and expression of the fliC gene were independent of IacP. FljB production was abolished by the deletion of the Hin DNA invertase but could be restored by the introduction of a plasmid carrying the hin gene. We also found that in the iacP mutant strain, the orientation of the invertible H segment is in the FljB-expressing phase. Furthermore, electron microscopy observations indicated that the iacP mutant strain had more flagella per cell than the wild-type strain. These results suggest that IacP is associated with flagellar phase switching under SPI1-inducing conditions.

Inhibition of VEGF transcription through blockade of the hypoxia inducible factor-1α-p300 interaction by a small molecule.

Vascular endothelial growth factor (VEGF) plays a pro-angiogenic role in tumor progression. Stabilization of a key regulator termed the hypoxia inducible factor (HIF)-1α under oxygen deficient environment around tumor is known to elicit expression of VEGF through binding to p300. Thus, inhibition of the HIF-1α-p300 interaction would lead to down-regulation of VEGF expression, thereby providing potential cancer therapeutics. Here, we have screened a chemical library against the interaction of the HIF-1α-derived peptide with p300 employing a fluorescence polarization-based assay. We have identified a compound as the most prominent inhibitor against the protein-protein interaction. Further, we have observed suppression of the mRNA level of VEGF upon treatment of HeLa cells with the compound, demonstrating its inhibitory effect at the cellular level.

Expression and delivery of tetanus toxin fragment C fused to the N-terminal domain of SipB enhances specific immune responses in mice.

Live attenuated bacteria can be used as a carrier for the delivery of foreign antigens to a host's immune system. The N-terminal domain of SipB, a translocon protein of the type III secretion system of Salmonella enterica serovar Typhimurium, is required for secretion and outer membrane localization. In the present study, vaccine plasmids for antigen delivery in which the non-toxic tetanus toxin fragment C (TTFC), which contains a T cell epitope, is fused to the N-terminal 160 amino acids of SipB were developed. It was found that the recombinant proteins are secreted into the culture media and localized to the bacterial surface. TTFC-specific antibody responses are significantly increased in mice orally immunized with attenuated S. Typhimurium BRD509 strains carrying TTFC delivery plasmids. When the TTFC delivery cassettes were introduced into a low copy vector, the plasmid was stably maintained in the BRD509 strain and induced an immune response to the TTFC antigen in mice. These results suggest that expression and delivery of heterologous antigens fused to the N-terminus of SipB enhance the induction of antigen-specific immune responses, and that the N-terminal domain of SipB can be used as a versatile delivery system for foreign antigens.

Development of an in vitro antigen-detection test as an alternative method to the in vivo plaque reduction neutralization test for the quality control of Japanese encephalitis virus vaccine.

Japanese encephalitis virus (JEV) causes diseases that attack the human central nervous system. Traditionally, the quality control for JEV vaccines, in which the plaque reduction neutralization (PRN) titer is measured by the national control laboratories before the vaccine batches are marketed, has required laboratory animal testing. However, classical animal tests have inherent problems, including the very fact that animals are used, ethical issues, and the possibility of error. In this study, JEV antigen was measured in an in vitro assay to assess the feasibility of replacing in vivo assays that measure the PRN titers of JEV vaccines. We constructed a double-sandwich enzyme-linked immunosorbent assay (DS-ELISA) that could detect JEV envelope (E). Initially, monoclonal antibodies (mAbs) directed against the JEV E protein were generated and characterized. We isolated 18 mAbs against JEV E protein, and most were the IgG1 or IgG2a isotype. The mAbs (5F15 and 7D71) were selected as the most suitable mAb pair to detect JEV E protein. DS-ELISA with this pair detected as little as approximately 3 µg/mL JEV E protein and demonstrated a relationship between the amount of JEV E protein and the PRN titer. From these results, we surmise that this DS-ELISA may be useful, not only in terms of measuring the amount of JEV E protein, but also as a substitute for the PRN test for JEV vaccine evaluation.

Clinical significance of right hepatectomy along the main portal fissure on donors in living donor liver transplantation.

There might be discordance between inter-lobar borders of the main portal fissure (MPF) using the middle hepatic vein (MHV) and of the portal segmentation. Forty-five living donors who underwent right hepatectomy for the adult recipients from 2007 to 2011 in a tertiary hospital were retrospectively analyzed. The donors were classified into conventional right hepatectomy along the MPF (cRL group, n = 26) and modified right hepatectomy along right-side shifted transection plane from the MPF (mRL group, n = 19). The cRL donors had higher postoperative peak level of INR (1.84 vs. 1.62; P = 0.022), and bilirubin (3.37 mg/dl vs. 2.74 mg/dl; P = 0.065) than the mRL donors. cRL donors experienced greater depression of platelet count (144 per nL vs. 168 per nL; P = 0.042) and enlargement of splenic volume (52% vs. 37%; P = 0.025) than mRL donors for 7 days after hepatectomy. The regeneration of the left lateral sector was more accelerated in the cRL donors than the mRL donors for postoperative 3 months (148% vs. 84%; P = 0.015). There were no differences in the post-transplant graft function, incidence of complications, and graft survival rates between the two groups of recipients (P > 0.05). This study suggests that the conventional right hepatectomy along the MHV might increase donor risk by reducing parenchymal liver volume of the segment IV.

Changes in thyroid peroxidase activity in response to various chemicals.

Thyroperoxidase (TPO) is a large heme-containing glycoprotein that catalyzes the transfer of iodine to thyroglobulin during thyroid hormone (TH) synthesis. Previously, we established an in vitro assay for TPO activity based on human recombinant TPO (hrTPO) stably transfected into human follicular thyroid carcinoma (FTC-238) cells. It is important to determine whether environmental chemicals can disrupt TPO activity because it is an important factor in the TH axis. In this study, we used our assay to examine the changes in TPO activity in response to various chemicals, including benzophenones (BPs), polycyclic aromatic hydrocarbons (PAHs), and persistent organic pollutants (POPs). Overall, BPs, PAHs, and POPs slightly altered TPO activity at low doses, as compared with the positive controls methimazole (MMI), genistein, and 2,2',4,4'-tetrahydroxy BP. Benzophenone, benzhydrol, 3-methylchloranthracene, pyrene, benzo(k)fluoranthene, benzo(e)pyrene, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and heptachlor decreased TPO activity, while 2,4-dihydroxy BP, 2,2'-dihydroxy-4-methoxy BP, and dibenzo(a,h)anthracene increased TPO activity. From these data, we can predict the disruption of TPO activity by various chemicals as a sensitive TH end point. TPO activity should be considered when enacting measures to regulate environmental exposure to thyroid-disrupting chemicals.

Ring stage classification of Babesia microti and Plasmodium falciparum using optical diffraction 3D tomographic technique.

BACKGROUND: Babesia is an intraerythrocytic parasite often misdiagnosed as a malaria parasite, leading to inappropriate treatment of the disease especially in co-endemic areas. In recent years, optical diffraction tomography (ODT) has shown great potential in the field of pathogen detection by quantification of three-dimensional (3D) imaging tomograms. The 3D imaging of biological cells is crucial to investigate and provide valuable information about the mechanisms behind the pathophysiology of cells and tissues. METHODS: The early ring stage of P. falciparum were obtained from stored stock of infected RBCs and of B. microti were obtained from infected patients during diagnosis. The ODT technique was applied to analyze and characterize detailed differences between P. falciparum and B. microti ring stage at the single cell level. Based on 3D quantitative information, accurate measurement was performed of morphological, biochemical, and biophysical parameters. RESULTS: Accurate measurements of morphological parameters indicated that the host cell surface area at the ring stage in B. microti was significantly smaller (140.2 ± 17.1 µm2) than that in P. falciparum (159.0 ± 15.2 µm2), and sphericities showed higher levels in B. microti-parasitized cells (0.66 ± 0.05) than in P. falciparum (0.60 ± 0.04). Based on biochemical parameters, host cell hemoglobin level was significantly higher and membrane fluctuations were respectively more active in P. falciparum-infected cells (30.25 ± 2.96 pg; 141.3 ± 24.68 nm) than in B. microti (27.28 ± 3.52 pg; 110.1 ± 38.83 nm). The result indicates that P. falciparum more actively altered host RBCs than B. microti. CONCLUSION: Although P. falciparum and B. microti often show confusable characteristics under the microscope, and the actual three-dimensional properties are different. These differences could be used in differential clinical diagnosis of erythrocytes infected with B. microti and P. falciparum.