An epidermal growth factor receptor-targeting immunotoxin based on IgG shows potent antitumor activity against head and neck cancer.

The epidermal growth factor receptor (EGFR) is an important target for cancer therapies. Many head and neck cancer (HNC) cells have been reported to overexpress EGFR; therefore, anti-EGFR therapies have been attempted in patients with HNC. However, its clinical efficacy is limited owing to the development of drug resistance. In this study, we developed an EGFR-targeting immunotoxin consisting of a clinically proven anti-EGFR IgG (cetuximab; CTX) and a toxin fragment (LR-LO10) derived from Pseudomonas exotoxin A (PE) using a novel site-specific conjugation technology (peptide-directed photo-crosslinking reaction), as an alternative option. The immunotoxin (CTX-LR-LO10) showed specific binding to EGFR and properties of a typical IgG, such as stability, interactions with receptors of immune cells, and pharmacokinetics, and inhibited protein synthesis via modification of elongation factor-2. Treatment of EGFR-positive HNC cells with the immunotoxin resulted in apoptotic cell death and the inhibition of cell migration and invasion. The efficacy of CTX-LR-LO10 was evaluated in xenograft mouse models, and the immunotoxin exhibited much stronger tumor suppression than CTX or LR-LO10. Transcriptome analyses revealed that the immunotoxins elicited immune responses and altered the expression of genes related to its mechanisms of action. These results support the notion that CTX-LR-LO10 may serve as a new therapeutic agent targeting EGFR-positive cancers.

Assessment of attenuation of varicella-zoster virus vaccines based on genomic comparison.

Live attenuated varicella-zoster virus (VZV) vaccines are used to prevent chickenpox and shingles. Single nucleotide polymorphisms (SNPs) that occur during the attenuation of parental strains are critical indicators of vaccine safety. To assess the attenuation of commercial VZV vaccines, genetic variants were comprehensively examined through high-throughput sequencing of viral DNA isolated from four VZV vaccines (Barycela, VarilRix, VariVax, and SKY Varicella). Whole-genome comparison of the four vaccines with the wild-type strain (Dumas) revealed that the sequences are highly conserved on a genome-wide scale. Among the 196 common variants across the four vaccines, 195 were already present in the genome of the parental strain (pOka), indicating that the variants occurred during the generation of the parental strain from the Dumas strain. Compared to the pOka genome, the vaccines exhibited distinct variant frequencies on a genome-wide and within an attenuation-related open reading frame. In particular, attenuation-associated 42 SNPs showed that Barycela, VarilRix, VariVax, and SKY Varicella are in ascending order regarding similarity with pOka-like genotypes, which in turn, might provide genomic evidence for the levels of attenuation. Finally, the phylogenetic network analysis demonstrated that genetic distances from the parental strain correlated with the attenuation levels of the vaccines.

Altered type 1 interferon responses in alloimmunized and nonalloimmunized patients with sickle cell disease.

Patients with sickle cell disease (SCD) have a high prevalence of RBC alloimmunization. However, underlying mechanisms are poorly understood. Given that proinflammatory type 1 interferons (IFNα/ß) and interferon stimulated genes (ISGs) promote alloimmunization in mice, we hypothesized that IFNα/ß may contribute to the increased frequency of alloimmunization in patients with SCD. To investigate this, expression of ISGs in blood leukocytes and peripheral blood mononuclear cells (PBMCs) of previously transfused SCD patients with or without alloimmunization and race-matched healthy controls were quantified, and IFNα/ß gene scores were calculated. IFNα/ß gene scores of SCD leukocytes and plasma cytokines were elevated, compared to controls (gene score, p < 0.01). Upon stimulation with IFNß, isolated PBMCs from patients with SCD had elevated ISGs and IFNα/ß gene scores (p < 0.05), compared to stimulated PBMCs from controls. However, IFNß-stimulated and unstimulated ISG expression did not significantly differ between alloimmunized and non-alloimmunized patients. These findings indicate that patients with SCD express an IFNα/ß gene signature, and larger studies are needed to fully determine its role in alloimmunization. Further, illustration of altered IFNα/ß responses in SCD has potential implications for IFNα/ß-mediated viral immunity, responses to IFNα/ß-based therapies, and other sequelae of SCD.

Antirrhinum majus L. flower extract inhibits cell growth and metastatic properties in human colon and lung cancer cell lines.

Snapdragon ( Antirrhinum majus L.) flowers are one of the most frequently used edible flowers in different preparations of foods and drinks. In this study, we examined inhibitory effects of snapdragon flower extract (SFE) against distinctive properties of cancer cells, stimulated growth, and activated metastasis, using H1299 lung cancer and HCT116 colon cancer cell lines. SFE treatment at 100-1,000 µg/ml for 24-72 hr resulted in a time- and dose-dependent growth inhibition in H1299 and HCT116 cells. Cell cycle analysis and Annexin V staining assay further revealed that SFE caused cell cycle arrest at G2/M phase and induction of apoptosis, indicating the growth inhibition by SFE is attributed to its G2/M cell cycle-arresting and apoptosis-inducing activities. SFE dose-dependently enhanced generation of intracellular reactive oxygen species (ROS) and reduced mitochondrial membrane potential in H1299 cells but had no effect on intracellular ROS levels in HCT116 cells, suggesting that the type of apoptosis induced by SFE in H1299 cells is different to that in HCT116 cells. Furthermore, SFE alleviated invasion, levels of matrix metalloproteinases, migration, and adhesion in H1299 and HCT116 cells. These results indicate that SFE not only inhibits cell growth by cell cycle arrest at G2/M and apoptosis induction but also alleviates metastatic properties such as invasion, migration, and adhesion in lung and colon cancer cells.

Inhibiting the Growth of Escherichia coli O157:H7 in Beef, Pork, and Chicken Meat using a Bacteriophage.

This study aimed to inhibit Escherichia coli (E. coli) O157:H7 artificially contaminated in fresh meat using bacteriophage. Among 14 bacteriophages, the highly lytic bacteriophage BPECO19 strain was selected to inhibit E. coli O157:H7 in artificially contaminated meat samples. Bacteriophage BPECO19 significantly reduced E. coli O157:H7 bacterial load in vitro in a multiplicity of infection (MOI)-dependent manner. E. coli O157:H7 was completely inhibited only in 10 min in vitro by the treatment of 10,000 MOI BPECO19. The treatment of BPECO19 at 100,000 MOI completely reduced 5 Log CFU/cm(2) E. coli O157:H7 bacterial load in beef and pork at 4 and 8h, respectively. In chicken meat, a 4.65 log reduction of E. coli O157:H7 was observed at 4 h by 100,000 MOI. The treatment of single bacteriophage BPECO19 was an effective method to control E. coli O157:H7 in meat samples.

Detection of viable murine norovirus using the plaque assay and propidium-monoazide-combined real-time reverse transcription-polymerase chain reaction.

Human norovirus (HuNoV) is the most common cause of gastroenteritis worldwide. The lack of a virus culture system makes it difficult to determine the viability of norovirus by only reverse transcription-polymerase chain reaction (RT-PCR) or real-time quantitative RT-PCR (qRT-PCR). The aim of this study was to investigate the detection of viable murine norovirus (MNV) by combining propidium monoazide (PMA) or ethidium monoazide (EMA) with qRT-PCR. MNV (5.21log10PFU/mL) was subjected to heat treatment at room temperature, 65, 70, 75, 80, 85, or 90°C in a water bath for 1min. The plaque assay, qRT-PCR, PMA-combined qRT-PCR, and EMA-combined qRT-PCR were then performed with heat exposed MNV samples. The MNV titer was reduced by 0.38, 1.34, and 3.71log10PFU/mL at temperatures of 65, 70, and 75°C, respectively. MNV was reduced >4.21log10PFU/mL at 80, 85, and 90°C heat inactivation. PMA (EMA) value equation for the interpretation of the viability of MNV was derived as follows: PMA (EMA) value=-logRN-logRP (RN: the relative quantity value of the not-treated sample, and RP: the relative quantity value of the PMA- or EMA-treated sample as determined by qRT-PCR). By PMA-combined qRT-PCR, the viable PMA value was 0.32, 0.83, and 2.62 for the 65, 70, and 75°C preheated MNVs, respectively. The viable PMA values for the viruses heated at 80, 85, and 90°C were all greater than 3.0, which was the cutoff value for discriminating between live and dead MNVs. The results of EMA-combined qRT-PCR were similar to those of qRT-PCR. Thus, PMA-combined qRT-PCR correlated well with the plaque assay in detecting viable MNVs.

Association between dietary calcium and phosphorus intakes, dietary calcium/phosphorus ratio and bone mass in the Korean population.

BACKGROUND: Osteoporosis has become a major public health issue. Among various factors affected bone health, not only dietary calcium and phosphorus intakes, but also the dietary calcium/phosphorus ratio could relate to bone health. Therefore, we evaluated whether dietary calcium and phosphorus intakes, and dietary calcium/phosphorus ratio are associated with bone mass in Korean adults ≥ 20 years of age. METHODS: The analysis used data from the Korean National Health and Nutrition Examination Survey, a cross-sectional survey of Korean civilians, conducted from January to December 2010. A total of 4,935 participants (2,309 men and 2,626 women) were analyzed in this study. Dietary calcium and phosphorus intakes of the participants were estimated using 24-h dietary recall. Bone mass densities for the whole body, femoral neck, and lumbar spine were measured by dual-energy X-ray absorptiometry. RESULTS: Dietary calcium intake and dietary calcium/phosphorus ratio were positively related to bone mass density for femoral neck in men ≥ 50 years of age (p = 0.046 and 0.041, respectively). Dietary calcium intake showed positive associations with bone mass density for whole body in premenopausal women (p = 0.022). CONCLUSIONS: Increased calcium intake and high dietary calcium/phosphorus ratio might have favorable effects on bone mass in Korean adults. Additional gender- and age-specific studies are needed to further identify the influence of calcium and phosphorus intakes, and the dietary calcium/phosphorus ratio on bone mass.

Inactivation of murine norovirus and feline calicivirus during oyster fermentation.

Fermented seafood is popular in Asian countries. This study examined the survival of feline calicivirus (FCV) and murine norovirus (MNV) during oyster fermentation. Oysters spiked with FCV and MNV were fermented with 5% or 10% salt at 18 °C for 15 days, and MNV and FCV titers, lactic acid bacteria (LAB) populations, pH, and enzymatic activity were measured at 0, 1, 3, 5, 7, 10, and 15 days post-fermentation (DPF). Reductions in MNV and FCV were greater in 5% NaCl-supplemented oysters than in 10% NaCl-supplemented oysters. In 5% NaCl oysters, MNV and FCV titers significantly decreased by 1.60 log and 3.01 log, respectively, at 15 DPF. Populations of LAB increased from 3.62 log10 colony-forming units/g at 0 DPF to 8.77 log10 colony-forming units/g at 15 DPF during oyster fermentation supplemented with 5% NaCl supplementation, and the pH decreased gradually from 5.38 at 0 DPF to 4.17 at 15 DPF. During oyster fermentation, α-amylase, proteinase, and lipase were produced at higher levels in 5% salted oysters than in 10% salted oysters (P < 0.01). We concluded that many of the antimicrobial factors produced in fermented oysters could contribute to a reduction in foodborne viruses.

The associations between serum zinc levels and metabolic syndrome in the Korean population: findings from the 2010 Korean National Health and Nutrition Examination Survey.

The prevalence of metabolic syndrome has been increasing rapidly worldwide. The functions of zinc may have a potential association with metabolic syndrome, but such associations have not been investigated extensively. Therefore, we examined the relationship between serum zinc levels and metabolic syndrome or metabolic risk factors among South Korean adults ≥ 20 years of age. The analysis used data from the Korean National Health and Nutrition Examination Survey, a cross-sectional survey of Korean civilians, conducted from January to December 2010. A total of 1,926 participants were analyzed in this study. Serum zinc levels in men were negatively associated with elevated fasting glucose (adjusted odds ratio [aOR], 0.58; 95% confidence interval [CI], 0.36-0.93) and positively associated with elevated triglycerides (aOR, 1.47; 95% CI, 1.01-2.13). A difference in serum zinc levels was detected in women, depending on the number of metabolic syndrome components (p = 0.002). Furthermore, serum zinc levels showed a decreasing trend with increasing numbers of metabolic syndrome components in women with metabolic syndrome. These findings suggest that serum zinc levels might be associated with metabolic syndrome or metabolic risk factors. Further gender-specific studies are needed to evaluate the effect of dietary or supplemental zinc intake on metabolic syndrome.

Effect of taurine feeding on bone mineral density and bone markers in rats.

The purpose of this study was to investigate the effect of dietary taurine supplementation on bone mineral density (BMD) and bone mineral content (BMC) in rats. Twenty Sprague-Dawley male rats (body weight 200 ± 10 g) were divided into two groups, control and taurine group (2% taurine-supplemented diet). All rats were fed on experimental diet and deionized water and libitum for 6 weeks. Serum alkaline phosphatase (ALP) activity, osteocalcin, PTH, and urinary deoxypyridinoline cross-links value were measured as markers of bone formation and resorption. BMD and BMC were measured using PIXImus (GE Lunar Co., Wisconsin) in spine and femur. The effect of diet on ALP, osteocalcine, and PTH was not significant. There were no significant differences in ALP, osteocalcine, and PTH concentration. Urinary calcium excretion was lower in taurine group than in control group. Femur BMC/weight of taurine group was significantly higher than control group. The results of this study showed the possible role of taurine in bone metabolism in male rats.

Kinetic and theoretical studies on alkaline ethanolysis of 4-nitrophenyl salicylate: effect of alkali metal ions on reactivity and mechanism.

Pseudo-first-order rate constants (k(obsd)) for reactions of 4-nitrophenyl salicylate (7) with alkali metal ethoxides (EtOM, M = K, Na, and Li) in anhydrous ethanol have been measured spectrophotometrically. Interestingly, the k(obsd) value decreases significantly as the concentration of EtOM increases. Because the phenolic moiety of substrate 7 would be deprotonated and exist as an anionic form (i.e., 7(-)) under kinetic conditions, the ground-state stabilization of 7(-) through formation of a six-membered cyclic complex with M(+) (i.e., 8) is proposed to be responsible for the decreasing k(obsd) trend. The k(obsd) value at a given concentration of EtOK increases steeply upon addition of [18]crown-6 ether (18C6) up to [18C6]/[EtOK] = 1 in the reaction mixture and then remains relatively constant thereafter. In contrast, k(obsd) decreases upon addition of salts (e.g., LiClO(4) or KSCN) to the reaction mixture, which indicates that M(+) ions inhibit the reaction. However, in the presence of 18C6, the k(obsd) value is independent of the concentration of EtOK but remains constant, which indicates that the reaction proceeds through a unimolecular mechanism in the presence of the complexing agent. Although two conceivable unimolecular pathways (formation of ketene 9 and lactone 10) can account for the kinetic results, the reaction has been concluded to proceed via formation of ketene 9 as the reactive intermediate on the basis of theoretical calculations.