Effect of modification methods on the physical properties and immunomodulatory activity of particulate β-glucan

β-Glucan is an immunoenhancing agent whose biological activities are linked to molecular structure. On that basis, the polysaccharide can be physiochemically modified to produce valuable functional materials. This study investigated the physical properties and immunostimulatory activity of modified β-glucan. Alkali-treated β-glucan had a distinct shape and smaller particle size than untreated β-glucan. The reduced particle size was conducive to the stability of the suspension because the β-glucan appeared to be completely dissolved by this treatment, forming an amorphous mass. Furthermore, alkali treatment improved the immunostimulating activity of β-glucan, whereas exposure of macrophages to heat-treated β-glucan decreased their immune activity. β-Glucan with reduced particle size by wet-grinding also displayed immunomodulatory activities. These results suggested that the particle size of β-glucan is a key factor in β-glucan-induced immune responses of macrophages. Thus, the modification of the β-glucan particle size provides new opportunities for developing immunoenhancing nutraceuticals or pharmacological therapies in the future.

Effects of vitamin E and selenium administration on transportation stress in pregnant dairy heifers

We investigated the effects of road transportation and administration of the vitamin E and selenium (ESe) on circulating cortisol, haptoglobin, blood metabolites, oxidative biomarkers, white blood cell profiles, and behaviors in pregnant dairy heifers. Forty pregnant Holstein heifers were randomly assigned to one of 4 treatments: no transportation and no ESe administration, no transportation and ESe administration, transportation and no administration, and transportation and ESe administration. The ESe (70 IU/kg dry matter feed of dl-α-tocopheryl acetate and 0.3 mg/kg dry matter feed of sodium selenite) was orally delivered once a day from 7 d before transportation to 3 d after transportation. The heifers were transported in trucks designed for cattle transportation. Blood was collected 1 h before transportation, immediately after transportation (IAT), and at 6, 24, and 48 h after transportation. Behaviors were recorded using a video camera for 2 consecutive days after transportation. Transported/non-ESe-administered heifers had greater cortisol at IAT, haptoglobin at 6 and 24 h after transportation, total oxidative status at 6 h after transportation, and nonesterified fatty acid levels, white blood cell numbers, and neutrophil percentages at IAT and 6 h after transportation in the blood than nontransported heifers. Transported/non-ESe-administered heifers had lower total antioxidative status levels at 48 h after transportation and lymphocyte percentages at IAT and 6 h after transportation than nontransported heifers. Lying time was shorter in transported heifers than nontransported/non-ESe-administered heifers. Transported/ESe-administered heifers had lower cortisol, total oxidative status, nonesterified fatty acid levels at IAT, and haptoglobin concentrations at 6 and 24 h after transportation than transported/non-ESe-administered heifers. Transported/ESe-administered heifers had greater total antioxidative status levels at 48 h after transportation than transported/non-ESe-administered heifers. No ESe administration effects were observed for white blood cell number and neutrophil and lymphocyte percentages and lying time. In conclusion, road transportation caused temporary oxidative stress. Administrating ESe partially alleviated the stress, suggesting that ESe administration could be a viable strategy to reduce stress in transported pregnant heifers, providing a novel role of vitamin E and selenium for improving animal welfare.

Encapsulation of Clofazimine by Cyclodextran: Preparation, Characterization, and In Vitro Release Properties

This study aimed to evaluate and compare the efficacy of cyclodextrans (CIs) and cyclodextrins (CDs) in improving the water solubility of a poorly water-soluble drug, clofazimine (CFZ). Among the evaluated CIs and CDs, CI-9 exhibited the highest percentage of drug inclusion and the highest solubility. Additionally, CI-9 showed the highest encapsulation efficiency, with a CFZ:CI-9 molar ratio of 0.2:1. SEM analysis indicated successful formation of inclusion complexes CFZ/CI and CFZ/CD, accounting for the rapid dissolution rate of the inclusion complex. Moreover, CFZ in CFZ/CI-9 demonstrated the highest drug release ratio, reaching up to 97%. CFZ/CI complexes were found to be an effective means of protecting the activity of CFZ against various environmental stresses, particularly UV irradiation, compared to free CFZ and CFZ/CD complexes. Overall, the findings provide valuable insights into designing novel drug delivery systems based on the inclusion complexes of CIs and CDs. However, further studies are needed to investigate the effects of these factors on the release properties and pharmacokinetics of encapsulated drugs in vivo, in order to ensure the safety and efficacy of these inclusion complexes. In conclusion, CI-9 is a promising candidate for drug delivery systems, and CFZ/CI complexes could be a potential formulation strategy for the development of stable and effective drug products.

One Carbon Ring Expansion of Bipyrrole to Bipyridine Enables Access to a π-Extended, Non-innocent, Corrole-like Ligand

A π-extended, diaza-triphenylene embedded, mono-anionic corrole analogue and its Ni^II complex were synthesized from a diaza-triphenylene precursor, which was obtained from a double one-carbon insertion into a naphthobipyrrole diester. Following conversion to the corresponding activated diol and acid-catalyzed condensation with pyrrole, subsequent reaction with pentafluorobenzaldehyde afforded mono-anionic, π-extended bipyricorrole-like macrocycle. Attempted Ni^II insertion with Ni(OAc)₂  ⋅ 4H₂ O resulted an ESR active, Ni^II bipyricorrole radical complex, which was converted to a stable cationic Ni^II complex upon treatment with [(Et₃ O)⁺ (SbCl₆ )^- ]. Both complexes were characterized by ¹ H and ¹³ C NMR, UV/Vis spectroscopy and single crystal X-ray diffraction analysis. The Ni^II bipyricorrole radical complex is converted to a cationic Ni^II complex by single-electron reduction using cobaltocene. Both the cationic Ni^II complex and the radical Ni^II complex exhibited ligand-centered redox behavior, whereas the Ni^II remains in the +2 oxidation state.

Effects of genomic estimated breeding value and dietary energy to protein ratio on growth performance, carcass trait, and lipogenic gene expression in Hanwoo steer

"Genome-based precision feeding" is a concept that involves the application of customised diets to different genetic groups of cattle. We investigated the effects of the genomic estimated breeding value (gEBV) and dietary energy to protein ratio (DEP) on growth performance, carcass traits, and lipogenic gene expression in Hanwoo (Korean cattle) steers. Forty-four Hanwoo steers (BW = 636 kg, age = 26.9 months) were genotyped using the Illumina Bovine 50 K BeadChip. The gEBV was calculated using genomic best linear unbiased prediction. Animals were separated into high gEBV of marbling score or low-gMS groups based on the upper and lower 50% groupings of the reference population, respectively. Animals were assigned to one of four groups in a 2 × 2 factorial arrangement: high gMS/high DEP (0.084 MJ/g), high gMS/low DEP (0.079 MJ/g), low gMS/high DEP, and low gMS/low DEP. Steers were fed concentrate with a high or low DEP for 31 weeks. The BW tended to be higher (0.05 < P < 0.1) in the high-gMS groups compared to the low-gMS groups at 0, 4, 8, 12, and 20 weeks. The average daily gain (ADG) tended to be lower (P = 0.08) in the high-gMS group than in the low-gMS group. Final BW and measured carcass weight (CW) were positively correlated with the gEBV of carcass weight (gCW). The DEP did not affect ADG. Neither the gMS nor the DEP affected the MS and beef quality grade. The intramuscular fat (IMF) content in the longissimus thoracis (LT) tended to be higher (P = 0.08) in the high-gMS groups than in the low-gMS groups. The mRNA levels of lipogenic acetyl-CoA carboxylase and fatty acid binding protein 4 genes in the LT were higher (P < 0.05) in the high-gMS group than in the low-gMS group. Overall, the IMF content tended to be affected by the gMS, and the genetic potential (i.e., gMS) was associated with the functional activity of lipogenic gene expression. The gCW was associated with the measured BW and CW. The results demonstrated that the gMS and the gCW may be used as early prediction indexes for meat quality and growth potential of beef cattle.

Nationwide trends of gatekeeper to invasive coronary angiography in suspected coronary artery disease

Funding Acknowledgements

Type of funding sources: None.

Background and Objectives

Real-world trends in the utility and type of gatekeeping studies in invasive coronary angiography (ICA) requires further investigation.

Methods

We identified outpatients who underwent noninvasive cardiac tests or directly ICA for suspected coronary artery disease (CAD) from the nationwide Korea Health Insurance Review and Assessment Service-National Patient Sample database between 2012 and 2018.

Results

Among 71,401 patients, the percentage of patients who were evaluated for suspected CAD was 34.7% for treadmill test (TMT), 4.2% for single-photon emission computed tomography (SPECT), 24.2% for coronary computed tomography angiography (CCTA), 1.6% for multiple gatekeepers, and 32.3% for directly ICA without noninvasive studies (Figure 1). The proportion of CCTA as a gatekeeper showed linear increase, (18.6% in 2012 and 28.8% in 2018; p &lt; 0.001), while those of TMT, SPECT, and direct ICA have decreased (p &lt; 0.001, p = 0.03, and p &lt; 0.001, respectively). The overall incidence of downstream ICA after gatekeeper was 13.8% (6,662/48,346), and SPECT showed higher ICA rate in pairwise comparison with TMT and CCTA (p &lt; 0.001). Patients who performed gatekeepers before ICA showed higher rate of subsequent PCI (34.7% vs. 32.3%; p &lt; 0.001) and CABG (3.5% vs. 1.0%; p &lt; 0.001), compared to those who directly underwent ICA, and CCTA was associated with higher revascularization rate after ICA in pairwise comparison with TMT and SPECT (p &lt; 0.001).

Conclusion

Nationwide database demonstrated that CCTA is utilized increasingly as a gatekeeper for ICA and is associated with high revascularization rate after ICA in outpatients with suspected CAD.

A J-aggregated nanoporphyrin overcoming phototoxic side effects in superior phototherapy with two-pronged effects

Phototherapy has been a promising therapeutic modality for pathological tissue due to its spatiotemporal selectivity and non-invasive characteristics. However, as a core component of phototherapy, a single photosensitizer (PS) nanoplatform integrating excellent therapeutic efficiency and minimal side effects remains an urgent but unmet need. Here, we construct a J-aggregated nano-porphyrin termed MTE based on the self-assembly of methyl-pheophorbide a derivative MPa-TEG (MT) and natural polyphenolic compound epigallocatechin gallate (EGCG). Due to the synergistic interaction between similar large π-conjugated structural EGCG and MT, MTE with small and uniform size is obtained by effectively hindering Ostwald ripening of MT. Noteworthily, MTE not only effectively avoids the inadvertent side effects of phototoxicity during transport thank to the ability of reactive oxygen species (ROS) scavenging, but also achieves two-pathway augmented superior phototherapy: (1) enhancing photodynamic therapy (PDT) via inhibiting the expression of anti-apoptosis protein surviving; (2) achieving adjuvant mild-temperature laser interstitial thermal therapy (LITT) via reducing the tumor thermoresistance on account that MTE inhibits the overexpression of HSP 70 and HSP 90. This research not only offers a facile strategy to construct multicomponent nanoplatforms but also provides a new pathway for efficient and low-toxicity phototherapy, which is beneficial to the future clinical application.

Stent expansion evaluated by optical coherence tomography and subsequent outcomes

Background

Regarding stent expansion indexes, previous optical coherence tomography (OCT) studies have shown minimal stent area (MSA) to be most predictive of adverse events.

Purpose

We sought to evaluate the impact of various stent expansion indexes by post-stent OCT on long-term clinical outcomes, and hence to find OCT-defined optimal stent expansion criteria.

Methods

Of the patients registered in the Yonsei OCT registry, a total of 1071 patients with 1123 native coronary artery lesions treated with new-generation drug-eluting stents under the OCT guidance and analyzable final post-stent OCT were included. Stent expansion indexes and different suboptimal stent expansion criteria were evaluated for their association with device-oriented clinical endpoints (DoCE) including cardiac death, target vessel-related myocardial infarction (TVMI) or stent thrombosis, and target lesion revascularization. Major safety events (MSE) included cardiac death, TVMI or stent thrombosis.

Results

The median follow-up period was 40.6 (interquartile range 22.0–50.0) months. As a continuous variable, MSA, adaptive volumetric stent expansion (stent volume/adaptive reference lumen volume) and overall volumetric stent expansion (stent volume/post-stent lumen volume) were significantly predictive of DoCE. As a categorical criteria, MSA &lt;5.0 mm2 (hazard ratio [HR] 3.80; 95% confidence interval [CI] 1.53–9.45), MSA/distal reference lumen area &lt;90% (HR 2.13; 95% CI 1.10–4.14), and overall volumetric stent expansion ≥96.6% (HR 2.38; 95% CI 1.09–5.22) were independently associated with DoCE after adjusting for confounders, and a total malapposition volume ≥7.0 mm3 (HR 3.38; 95% CI 1.05–10.93) was linked to MSE.

Conclusions

This OCT study highlights that sufficient stent expansion to achieve adequate absolute MSA and relative MSA by distal reference lumen area and alleviate significant malapposition is important to improve clinical outcome, but overall stent overexpansion may have deleterious effect.

Funding Acknowledgement

Type of funding sources: None.

The long-term cardiac events after coronary bifurcation stenting with second-generation drug-eluting stents in elderly patients are comparable to those of younger patients

Background

Elderly patients undergoing percutaneous coronary intervention (PCI) generally have a high risk of adverse clinical outcomes. We investigated the long-term clinical impact of PCI on coronary bifurcation disease in elderly patients in Korea and Italy.

Methods

From the BIFURCAT (comBined Insights from the Unified RAIN and COBIS bifurcAtion regisTries) data, we evaluated 5,537 patients who underwent PCI for coronary bifurcation disease. The primary outcome was major adverse cardiac events (MACEs), defined as the composite of target vessel myocardial infarction, target lesion revascularisation, and stent thrombosis. Kaplan–Meier estimates and Cox proportional hazard models were used to compare elderly patients (aged ≥75 years) and younger patients (aged &lt;75 years).

Results

A total of 1,415 patients (26%) were aged ≥75 years. Elderly patients were more frequently female, had higher rates of hypertension and chronic kidney disease (CKD), and presented more frequently with left main (LM) disease. After a median follow-up of 2.1 years, MACEs were comparable between elderly and younger patients. In multivariable analysis, old age was not an independent predictor of MACEs (p=0.977). In elderly patients, CKD and LM disease were independent predictors of MACEs, whereas in younger patients, hypertension, diabetes, CKD, reduced left ventricular ejection fraction, LM disease, and two-stent strategy usage were independent predictors.

Conclusions

Elderly patients who underwent coronary bifurcation PCI with second-generation drug-eluting stents demonstrated similar clinical outcomes to those of younger patients. Both CKD and LM disease were independent predictors of MACEs, regardless of age after coronary bifurcation PCI.

Funding Acknowledgement

Type of funding sources: None.

The differential effects of antihypertensive drugs on central blood pressure: nebivolol versus telmisartan (ATD-CBP)

Background

Central blood pressure and central pulse pressure have a better correlation with the risk of cardiovascular disease compared to those of peripheral measurement. In a previous study, a second-generation beta-blocker showed poor CBP-lowering effects. However, the effect on CBP by third-generation beta-blockers is not fully elucidated. Thus, this randomised study investigated whether nebivolol-based hypertension treatment may confer advantages over telmisartan, an angiotensin II receptor-blocker, in reducing CBP.

Methods

This was a prospective, randomised, multicentre, open-label, controlled trial that evaluated 98 hypertensive patients. Patients received either nebivolol- (N=49) or telmisartan-based (N=49) treatment for hypertension for 12 weeks with a target BP of ≤140/80. The primary outcome was the difference in change from baseline central systolic BP (cSBP) after 12 weeks.

Results

There were no significant differences between the two groups in baseline central and peripheral SBP. The mean change in cSBP from baseline (ΔcSBP) was −17.2±3 mmHg for nebivolol group (P&lt;0.001) and −29.9±3 mmHg for telmisartan group (P&lt;0.001). The difference in ΔcSBP between the two groups was significant (12.7mmHg, 95% confidence interval [CI], 4.13 to 21.2; P=0.004). Peripheral SBP (pSBP) decreased less in nebivolol group compared to telmisartan group (−18.0±3 in nebivolol group vs. −26.3±3 in telmisartan group, P=0.032). After adjusting for reduction in pSBP, reduction in cSBP was higher in telmisartan group compared to nebivolol group, as shown by the ratio of changes in cSBP and pSBP (ΔcSBP/ΔpSBP; 0.67 for nebivolol group vs. 1.11 for telmisartan group, P=0.080), albeit without statistical significance.

Conclusions

Nebivolol-based hypertension treatment may have less potent CBP-lowering effects compared to telmisartan. However, larger-scale studies are warranted to further elaborate our findings.

Funding Acknowledgement

Type of funding sources: None.

Effect of an early invasive strategy based on time of symptom onset in patients with non-ST elevation myocardial infarction

Background

A limitation of the current guidelines of the timing of invasive coronary angiography (ICA) for patients with non-ST-segment elevation (NSTE) acute coronary syndrome is based on randomization time. So far, no study has reported the clinical outcomes of invasive strategy timing based on the time of symptom onset. Herein, we aimed to investigate the effect of invasive strategy timing from the time of symptom onset on the 3-year clinical outcomes of patients with NSTE myocardial infarction (MI).

Methods and results

Among 13,104 patients from the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we evaluated 5,856 patients with NSTEMI. The patients were categorized according to symptom-to-catheter (StC) time (&lt;48 h and ≥48 h). The primary outcome was 3-year all-cause mortality, and the secondary outcome was a 3-year composite of all-cause mortality, recurrent MI, and hospitalization for heart failure. Overall, 3,919 (66.9%) patients were classified into the StC time &lt;48 h group. This group had lower all-cause mortality than the StC time ≥48 h group (7.3% vs. 13.4%, p&lt;0.001). The continuous association of StC time and risk of primary and secondary endpoints showed shorter StC time (reference: 48 h), and lower adjusted hazard ratio reduction was observed. In multivariable analysis, independent predictors of delayed ICA were older age, non-specific symptoms, no use of emergency medical services, no ST-segment deviation, chronic kidney disease, and Global Registry of Acute Coronary Events score &gt;140.

Conclusion

Early invasive strategy based on the StC time improves all-cause mortality in patients with NSTEMI.

Funding Acknowledgement

Type of funding sources: None.

Enhanced biotransformation of the minor ginsenosides in red ginseng extract by Penicillium decumbens β-glucosidase

Compound K (C-K) and Rh2, which are present at low levels in ginseng and ginseng extracts, have higher intestinal absorption rates than other ginsenosides. Here, we attempted to convert ginsenoside Rb1 to C-K using a β-glucosidase from Penicillium decumbens. Ten commercially available enzymes were screened to identify enzymes that can convert ginsenoside Rb1 to C-K, resulting in the selection of a P. decumbens-derived β-glucosidase. β-Glucosidase showed maximum activity at pH 4.0 and 60 °C; its substrate specificity for ginsenoside Rb1 was investigated. The main glucoside-hydrolyzing pathways were as follows: ginsenoside Rb1 or Rd → gypenoside XVII → F2 → C-K and ginsenoside Rg3 → Rh2. The P. decumbens-derived β-glucosidase was used to generate C-K and Rh2 using protopanaxadiol-type ginsenosides as substrates. Additionally, to apply this enzyme to the commercialized red ginseng extract products, the contents of C-K and Rh2 in the total ginsenosides significantly (p < 0.05) increased up to 36-fold and 8.9-fold, respectively, higher than prior to subjecting to biotransformation. To the best of our knowledge, this is the first report of the dual biotransformation of C-K and Rh2 by a food-grade commercial enzyme. This study demonstrates that the use of a specific β-glucosidase may increase C-K and Rh2 contents in the ginseng extract through a simple biotransformation process and, thus, enhance its health benefits.

Synthesis and characteristics of a rebaudioside-A like compound as a potential non-caloric natural sweetener by Leuconostoc kimchii dextransucrase

Stevioside (ST) is currently considered as a highly-demanded natural and zero-caloric replacer of sucrose with several health-promoting properties. Nonetheless, its bitter aftertaste limits its use in the food industry. Herein, glucosyl steviosides were synthesized using primarily a food-grade lactic acid bacteria, Leuconostoc kimchii dextransucrase and conversion yield (%) was 40.3%. A glucose moiety was transferred stereo-selectively to ST by α-1,6-linkage and this is the first report about obtaining rebaudioside A (Reb-A) like glucosyl stevioside-2 (STG-2). Glucosyl steviosides revealed greatly improved stability up to 120 °C and remained stable over 32.1% and 58.12% in the pH (1.4) compared with 30.55% of ST. Moreover, the glucosylated steviosides improved the stability, reaching 95% after 30 days and Reb-A like compound (STG-2) especially exhibited higher stability in commercial beverages. Furthermore, the glucosyl steviosides showed over 1.92- and 2.24-fold decreases than that of enzymatically modified ST in the glucose generation rate test.

Increased risk of chronic otitis media in chronic rhinosinusitis patients: a longitudinal follow-up study using a national health screening cohort

BACKGROUND

Chronic rhinosinusitis (CRS) and chronic otitis media (COM) share pathophysiological mechanisms such as bacterial infection, biofilm, and persistence of the obstruction state of ventilation routes. However, only a few studies have investigated the relationship between these two diseases nationwide and in the general population. The purpose of this study was to determine whether the incidence of COM in patients with CRS differed from that of a matched control from the national health screening cohort.

METHODS

Data from the Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2015. Participants who were treated ≥ ≥ ≥2 times and underwent head and neck computed tomography evaluation were selected. A 1:4 matched CRS group (n=8,057) and a control group (n=32,228) were selected. The control group included participants who were never treated with the ICD-10 code J32 from 2002 to 2015. The CRS group included CRS patients with/without nasal polyps.

RESULTS

The incidence of COM was significantly higher in the CRS group than in the control group. In a subgroup analysis, the incidence of COM in all age groups and in men and women was significantly higher in the CRS group than in the control group. More, CRS increased the risk of COM.

CONCLUSIONS

A significant association was observed between CRS and COM. This indicates that CRS patients have a high risk of developing COM.

Effects of superfine grinding using ball-milling on the physical properties, chemical composition, and antioxidant properties of Quercus salicina (Blume) leaf powders

BACKGROUND

Quercus salicina (Blume) leaves are traditionally used as folk medicine in some Asian countries. The aim of this study was to evaluate the effects of ball milling for different periods (0, 6, 12, 18, and 24 h) on the physicochemical properties of superfine Quercus salicina (Blume) leaf (QSL) powders.

RESULTS

The particle sizes, water-holding capacity, angle of repose, and redness of the superfine QSL powder decreased with increasing ball-milling times, whereas the water solubility index, bulk density, tapped density, brightness, and yellowness were found to increase. Significantly higher (P > 0.05) total phenolic and flavonoid contents, and antioxidant activities, were observed for the superfine QSL powders obtained after 24 h ball-milling time. A total of 12 phenolic compounds in free and cell-wall-bound forms were quantified in the superfine QSL powder. Free phenolics such as protocatechuic acid, caffeic acid, rutin, and p-coumaric acid were increased and all cell-wall-bound phenolics were decreased with increasing ball-milling times. The antioxidant activity of the free phenolics increased with increasing ball-milling times, and the cell-wall-bound forms decreased.

CONCLUSION

Superfine grinding by ball milling for 24 h can thus be used to produce superfine QSL powder with higher free phenolic metabolite content and antioxidant activity, and improved water solubility index, color, bulk, and tapped densities. This study will be useful for the food / nutraceutical / pharmaceutical industries in the manufacturing of active food ingredients or value-added products using QSL powders. © 2020 Society of Chemical Industry.

Improved cortical activity and reduced gait asymmetry during poststroke self-paced walking rehabilitation

Background

For patients with gait impairment due to neurological disorders, body weight-supported treadmill training (BWSTT) has been widely used for gait rehabilitation. On a conventional (passive) treadmill that runs at a constant speed, however, the level of patient engagement and cortical activity decreased compared with gait training on the ground. To increase the level of cognitive engagement and brain activity during gait rehabilitation, a self-paced (active) treadmill is introduced to allow patients to actively control walking speed, as with overground walking.

Methods

To validate the effects of self-paced treadmill walking on cortical activities, this paper presents a clinical test with stroke survivors. We hypothesized that cortical activities on the affected side of the brain would also increase during active walking because patients have to match the target walking speed with the affected lower limbs. Thus, asymmetric gait patterns such as limping or hobbling might also decrease during active walking.

Results

Although the clinical test was conducted in a short period, the patients showed higher cognitive engagement, improved brain activities assessed by electroencephalography (EEG), and decreased gait asymmetry with the self-paced treadmill. As expected, increases in the spectral power of the low γ and β bands in the prefrontal cortex (PFC), premotor cortex (PMC), and supramarginal gyrus (SG) were found, which are possibly related to processing sensory data and planning voluntary movements. In addition, these changes in cortical activities were also found with the affected lower limbs during the swing phase. Since our treadmill controller tracked the swing speed of the leg to control walking speed, such results imply that subjects made substantial effort to control their affected legs in the swing phase to match the target walking speed.

Conclusions

The patients also showed reduced gait asymmetry patterns. Based on the results, the self-paced gait training system has the potential to train the symmetric gait and to promote the related cortical activities after stroke.

Trial registration Not applicable

Synthesis of improved long-chain isomaltooligosaccharide, using a novel glucosyltransferase derived from Thermoanaerobacter thermocopriae, with maltodextrin

Isomaltooligosaccharide (IMO), considered to be a prebiotic, reportedly has health effects, particularly in terms of digestion; however, the prebiotic effects of IMOs depend largely on the degree of polymerization. Currently, IMOs are commercially produced using transglucosidase (TG) derived from Aspergillus niger. Here, we report a novel Thermoanaerobacter thermocopriae-derived TG (TtTG) that can produce long-chain IMOs (L-IMOs) using maltodextrin as the main substrate. A putative carbohydrate-binding gene comprising carbohydrate-binding module 35 and glycoside hydrolase family 15 domain was cloned and successfully overexpressed in Escherichia coli BL21 (DE3) cells. The resulting purified recombinant enzyme (TtTG) had a molecular mass of 94 kDa. TtTG displayed an optimal pH of 4.0 (higher than that of commercial TG) and an optimal temperature of 60 °C (same as that of commercial TG). TtTG also enabled the synthesis of oligosaccharides using various saccharides, such as palatinose, kojibiose, sophorose, maltose, cellobiose, isomaltose, gentiobiose, and trehalose, which acted as specific acceptors. TtTG could also produce a medium-sized L-IMO, different from that by dextran-dextrinase and TG, from maltodextrin, as the sole substrate. Thus, the novel combination of maltodextrin and TtTG shows potential as an effective method for commercially producing L-IMOs with improved prebiotic effects.

Post Synthetic Modification of Planar Antiaromatic Hexaphyrin (1.0.1.0.1.0) by Regio-Selective, Sequential SNAr

In spite of unique structural, spectroscopic and redox properties, the synthetic variants of the planar, antiaromatic hexaphyrin (1.0.1.0.1.0) derivatives 2, has been limited due to the low yields and difficulty in access to the starting material. A chemical modification of the meso-substituents could be good alternative overcoming the synthetic barrier. Herein, we report a regio-selective nucleophilic aromatic substitution (S_NAr) of meso-pentafluorophenyl group in rosarrin 2 with catechol. The reaction afforded benzodioxane fused rosarrin 3 as single product with high yield. The intrinsic antiaromatic character of the starting rosarrin 2 retained throughout the reactions. Clean, two electron reduction was achieved by treatment of 3 with SnCl₂•2H₂O affording 26π-electron aromatic rosarrin 4. The synthesized compounds exhibited noticeable changes in photophysical and redox properties compared with starting rosarrin 2.

Liquid crystal filter based tunable transmitter for 25Gps wavelength division multiplexing-passive optical network fronthaul

A novel tunable transmitter structure based on liquid crystal filter, to the best of our knowledge, is presented. The structure is designed for application to 5G fronthaul and supports 25 Gbps dense wavelength division multiplexing (WDM) transmission and tunable range of 35 nm. The design takes into account easy change of operation band over coarse WDM grid. Prototype samples are developed to test feasibility of the design.

Noncovalent Intermolecular Interaction in Cofacially Stacked 24π Antiaromatic Hexaphyrin Dimer

π-π Stacking is omnipresent not only in nature but in a wide variety of practical fields applied to our lives. Because of its importance in a performance of natural and artificial systems, such as light harvesting system and working layer in device, many researchers have put intensive effort into identifying its underlying nature. However, for the case of π-π stacked systems composed of antiaromatic units, the understanding of the fundamental mechanisms is still unclear. Herein, we synthesized a new type of planar β,β'-phenylene-bridged hexaphyrin (1.0.1.0.1.0), referred as naphthorosarin which possesses the 24π-electron conjugated pathway. Especially, the corresponding antiaromatic porphyrinoid shows the unique property to form dimeric species adopting the face-to-face geometry which is unprecedented in cases of known annulated naphthorosarins. In order to elucidate the intriguing properties derived from the stacked dimer, the current study focuses on the experimental support to rationalize the observed π-π interactions between the two subunits.

Gamma-Aminobutyric Acid Production from a Novel Enterococcus avium JS-N6B4 Strain Isolated from Edible Insects

Gamma-aminobutyric acid (GABA)-producing strains were isolated from four edible insects and subjected to 16S rRNA sequence analysis. Among the four GABA-producing bacteria, Enterococcus avium JS-N6B4 exhibited the highest GABA-production, while cultivation temperature, initial pH, aerobic condition, and mono-sodium glutamate (MSG) feeding were found to be the key factors affecting GABA production rate. The culture condition was optimized in terms of glucose, yeast extract, and MSG concentrations using response surface methodology (RSM). GABA production up to 16.64 g/l was obtained under the conditions of 7 g/l glucose, 45 g/l yeast extract, and 62 g/l MSG through the optimization of medium composition by RSM. Experimental GABA production was 13.68 g/l, which was close to the predicted value (16.64 g/l) calculated from the analysis of variance, and 2.79-fold higher than the production achieved with basic medium. Therefore, GABA-producing strains may help improve the GABA production in edible insects, and provide a new approach to the use of edible insects as effective food biomaterials.

Trapping of Stable [4n+1] π-Electron Species from Peripherally Substituted, Conformationally Rigid, Antiaromatic Hexaphyrins

Peripherally substituted antiaromatic naphthorosarins have been synthesized for the first time. The synthesis was accomplished by acid-catalyzed condensation of naphthobipyrrole building blocks with aromatic aldehydes. The naphthobipyrrole building blocks were synthesized by simple oxidative coupling of the corresponding pyrrole substituted aromatics. Solid-state structural analyses of the synthesized naphthorosarins revealed that the presence of meso-2,6-dichlorophenyl- and 5,6-difluoro-substitution substantially alter the geometry and properties of the naphthorosarins. The substituents affect the redox potentials as well and, in turn, the proton-coupled electron-transfer processes leading to the formation of one- and two-electron reduced forms of the corresponding naphthorosarins. One particular naphthorosarin that bears both peripheral fluorine and meso-2,6-dichlorophenyl substituents forms a stable 25 π-electron species upon treating with TFA that was characterized by single-crystal X-ray diffraction analysis. The current study underscores how structural modifications can be used to fine-tune the electronic features of naphthorosarins, including stabilization of odd electron species.

meso-Alkylidenyl dibenzihexaphyrins: synthesis and protonation studies

The synthesis and characterization of the alkylidenyl-dibenzihexaphyrins bearing four indanedionyl groups at themeso-positions linkedviafourmeso-exocyclic double bonds is reported.

The 100 Most-Cited Articles Focused on Ultrasound Imaging: A Bibliometric Analysis

Purpose The number of citations that an article has received reflects its impact on a particular research area. The aim of this study was to identify the 100 most-cited articles focused on ultrasound (US) imaging and to analyze the characteristics of these articles. Methods We determined the 100 most-cited articles on US imaging via the Web of Science database, using the search term. The following parameters were used to analyze the characteristics of the 100 most-cited articles: publication year, journal, journal impact factor, number of citations and annual citations, authors, department, institution, country, type of article, and topic. Results The number of citations for the 100 most-cited articles ranged from 1849 to 341 (median: 442.0) and the number of annual citations ranged from 108.0 to 8.1 (median: 22.1). The majority of articles were published in 1990 - 1999 (39 %), published in radiology journals (20 %), originated in the United States (45 %), were clinical observation studies (67 %), and dealt with the vessels (35 %). The Department of Internal Medicine at the University of California and the Research Institute of Public Health at the University of Kuopio (n = 4 each) were the leading institutions and Salonen JT and Salonen R (n = 4 each) were the most prolific authors. Conclusion Our study presents a detailed list and analysis of the 100 most-cited US articles, which provides a unique insight into the historical development in this field.

Histopathological findings in wild Nutrias (Myocastor coypus) with Capillaria hepatica infection

Capillaria hepatica is a zoonotic nematode that uses rodents and other mammals as hosts, especially rats and mice, and causes hepatic granuloma and eventually fibrosis/cirrhosis. However, C. hepatica infection in nutria, a large semiaquatic rodent, has rarely been reported, and histopathologic features of the infection have not been described in detail. We conducted necropsy on 36 wild nutrias. Some animals were found to have milky spots, parasitic eggs and worms within hepatic microgranuloma involving central calcification with cell debris, macrophages, eosinophils and multinucleated giant cells (MGCs). Interestingly, the eggs were closely surrounded by MGCs and appeared to be destroyed without inducing further chronic changes. Based on microscopical examination, C. hepatica infection was diagnosed, and we describe its histopathological characteristics in wild nutrias.

[Forensic Analysis of 20 Dead Cases Related to Heroin Abuse]

OBJECTIVES

To perform retrospective analysis on 20 dead cases related to heroin abuse, and to provide references for the forensic assessment of correlative cases.

METHODS

Among 20 dead cases related to heroin abuse, general situation, using method of drug, cause of death and result of forensic examination were analyzed by statistical analysis for summarizing the cause of death and pathologic changes.

RESULTS

The dead were mostly young adults, with more male than female. The results of histopathological examinations showed non-specific pathological changes. There were four leading causes of death, including acute poisoning of heroin abuse or leakage （13 cases, 65%）, concurrent diseases caused by heroin abuse （3 cases, 15%）, inspiratory asphyxia caused by taking heroin （2 cases, 10%）, and heroin withdrawal syndrome （2 cases, 10%）.

CONCLUSIONS

The forensic identification on dead related to heroin abuse must base on the comprehensive autopsy, and combine with the qualitative and quantitative analysis of heroin and its metabolites in death and the case information, as well as the scene investigation.

Risk factors for recurrence in patients with papillary thyroid carcinoma undergoing modified radical neck dissection

BACKGROUND

This study evaluated the impact of lymph node-related factors on the risk of and site of recurrence in patients who had papillary thyroid carcinoma with lymph node metastasis in the lateral compartment (classified as pN1b).

METHODS

Patients underwent total thyroidectomy with unilateral modified radical neck dissection for classical papillary thyroid carcinoma. Risk factors for recurrence were evaluated according to the pattern of recurrence.

RESULTS

A total of 324 patients were included in the study. The median follow-up was 63 (range 14-181) months. Recurrence was detected in 47 patients (14·5 per cent). In the multivariable analysis, a maximum diameter of metastatic lymph nodes larger than 2·0 cm (hazard ratio (HR) 1·15, 95 per cent c.i. 1·06 to 1·25; P = 0·033) and a central compartment metastatic lymph node ratio of more than 0·42 (HR 3·35, 1·65 to 6·79; P < 0·001) were identified as independent risk factors for locoregional recurrence. Age 45 years or older (HR 5·69, 1·24 to 26·12; P = 0·025) and extranodal extension of metastasis (HR 12·71, 1·64 to 98·25; P = 0·015) were risk factors for distant metastasis. In subgroup analysis of locoregional recurrence, several lymph node-related factors affected the risk of recurrence according to the specific site of metastasis.

CONCLUSION

Lymph node-related factors are of importance for the risk of recurrence in patients with classical papillary thyroid carcinoma classified as pN1b.

Association between catechol-O-methyl transferase gene polymorphisms and fibromyalgia in a Korean population: A case-control study

BACKGROUND

Although polymorphisms of the catechol-O-methyl transferase (COMT) gene have been implicated in altered pain sensitivity, results concerning the association between COMT gene polymorphisms and fibromyalgia (FM) are equivocal. We assessed the associations between COMT single-nucleotide polymorphisms (SNP) and FM risk and symptom severity.

METHODS

In total, 409 FM patients and 423 controls were enrolled. Alleles and genotypes at five positions [rs6269 (A>G), rs4633 (C>T), rs4818 (C>G), rs4680 (C>G) and rs165599 (A>G)] in the COMT gene were genotyped from peripheral blood DNA.

RESULTS

Alleles and genotypes of the rs4818 COMT gene polymorphism were significantly associated with increased susceptibility to FM. The rs4818 GG genotype was more strongly associated with FM compared to the CC genotype (OR = 1.680, 95% CI: 1.057, 2.672, p = 0.027). Although allele and genotype frequencies did not differ among groups, the rs4633 CT genotype was not associated with the presence of FM following adjustment for age and sex (OR = 0.745; 95% CI: 0.558, 0.995; p = 0.046). However, no association was observed between clinical measures and individual COMT SNPs. In haplotype analysis, there was a significant association between ACG haplotype and FM susceptibility sex (OR = 2.960, 95% CI: 1.447, 6.056, p = 0.003) and the number of tender points (p = 0.046).

CONCLUSIONS

This large-scale study suggests that polymorphisms of the COMT gene may be associated with FM risk and pain sensitivity in Korean FM patients. However, our results differed to those of previous studies, suggesting ethnic variation in COMT gene polymorphisms in FM.

WHAT DOES THIS STUDY ADD

By contrast to Caucasian and Latin-American populations, the COMT gene polymorphisms are associated with FM risk and pain sensitivity in Korean FM patients, suggesting ethnic variation in COMT gene polymorphisms.

Influence of arm position on catheter placement during real-time ultrasound-guided right infraclavicular proximal axillary venous catheterization

BACKGROUND

Real-time ultrasound-guided infraclavicular proximal axillary venous catheterization is used in many clinical situations and provides the advantages of catheter stabilization, a reduced risk of catheter-related infection, and comfort for the patient without limitation of movement. However, unintended catheter tip dislocation and accidental arterial puncture occur occasionally. This study was designed to investigate the influence of arm position on catheter placement and complications.

METHODS

Patients were randomized to either the neutral group (n=240) or the abduction group (n=241). In the neutral group, patients were positioned with the head and shoulders placed in an anatomically neutral position and the arms kept by the side during catheterization. In the abduction group, the right upper arm was abducted at 90° from the trunk during catheterization. After real-time ultrasound-guided catheterization was carried out in the right infraclavicular proximal axillary vein, misplacement of the catheter and all complications were evaluated with ultrasound and chest radiography.

RESULTS

The success rate of complete catheterization before evaluating the placement of the catheter was high in both groups (97.1 vs 98.8%, P=not significant). The incidence of accidental arterial puncture was not different (1.7 vs 0%, P=not significant). The incidence of misplacement of the catheter was higher in the neutral group than in the abduction group (3.9 vs 0.4%, P=0.01). There were no complications, such as haemothorax, pneumothorax, or injury to the brachial plexus and phrenic nerve, in either group.

CONCLUSIONS

Upper arm abduction may minimize the risk of misplacement of the catheter during real-time ultrasound-guided infraclavicular proximal axillary venous catheterization.

CLINICAL TRIAL REGISTRATION

The trial was registered with the Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp. Identifier: KCT0001417.

Microporous carbon nanosheets with redox-active heteroatoms for pseudocapacitive charge storage

We report microporous carbon nanosheets containing numerous redox active heteroatoms fabricated from exfoliated waste coffee grounds by simple heating with KOH for pseudocapacitive charge storage. We found that various heteroatom combinations in carbonaceous materials can be a redox host for lithium ion storage. The bio-inspired nanomaterials had unique characteristics, showing superior electrochemical performances as cathode for asymmetric pseudocapacitors.

Rate and associated factors of solifenacin add-on after tamsulosin monotherapy in men with voiding and storage lower urinary tract symptoms

AIM

To explore the rate of add-on therapy with solifenacin in men with voiding and storage lower urinary tract symptoms (LUTS) after tamsulosin monotherapy and to explore predictive factors for starting solifenacin add-on therapy.

METHODS

Men aged ≥ 45 years with IPSS ≥ 12 and symptoms of OAB (OAB-V8 ≥ 8, micturition ≥ 8/24 h, urgency ≥ 2/24 h) were enrolled to receive tamsulosin 0.2 mg once daily. After 4 weeks, men with residual symptoms of OAB and reported 'dissatisfied' or 'a little satisfied' were received solifenacin 5 mg in combination with tamsulosin monotherapy. Subjects completed an IPSS, a Quality of life (QoL) index, OAB V8, and an International Consultation of Incontinence Questionnaire (ICIQ)-Male LUTS, and patient perception of bladder condition (PPBC) at baseline and week 4.

RESULTS

Of a total of 305 patients, 254 patients completed 4 weeks of tamsulosin treatment. For 176 patients, solifenacin was added (69.3%). Significant predictive factors of solifenacin add-on therapy included long LUTS duration, high IPSS, number of micturitions per 24 h, more urgency episodes, high urgency severity score in a voiding diary and high OAB V8 score. Based on multivariable analysis, potential predictive factors of solifenacin add-on therapy included long LUTS duration (OR = 1.008, 95% CI: 1.001-1.014), high serum PSA (OR = 1.543, 95% CI: 1.136-2.095) and small prostate size (OR = 0.970, 95% CI: 0.947-0.994) (p < 0.05). IPSS, daytime micturitions and urgency episodes, OAB V8 scores, ICIQ and PPBC were improved after tamsulosin monotherapy.

CONCLUSIONS

Two thirds of men with voiding and storage LUTS needed to add anticholinergics after 4 weeks of tamsulosin monotherapy. Patients with longer lasting symptoms and storage symptoms with small prostate volume may require the anticholinergic add-on.

Feasibility of using auto Mod-MPI system, a novel technique for automated measurement of fetal modified myocardial performance index

OBJECTIVES

To evaluate the reproducibility of measurement of the fetal left modified myocardial performance index (Mod-MPI) determined using a novel automated system.

METHODS

This was a prospective study of 116 ultrasound examinations from 110 normal singleton pregnancies at 12 + 1 to 37 + 1 weeks' gestation. Two experienced operators each measured the left Mod-MPI twice manually and twice automatically using the Auto Mod-MPI system. Intra- and interoperator reproducibility were assessed using intraclass correlation coefficients (ICCs) and the manual and automated measurements obtained by the more experienced operator were compared using Bland-Altman plots and ICCs.

RESULTS

Both operators successfully measured the left Mod-MPI in all cases using the Auto Mod-MPI system. For both operators, intraoperator reproducibility was higher when performing automated measurements (ICC = 0.967 and 0.962 for Operators 1 and 2, respectively) than when performing manual measurements (ICC = 0.857 and 0.856 for Operators 1 and 2, respectively). Interoperator agreement was also better for automated than for manual measurements (ICC = 0.930 vs 0.723, respectively). There was good agreement between the automated and manual values measured by the more experienced operator.

CONCLUSIONS

The Auto Mod-MPI system is a reliable technique for measuring fetal left Mod-MPI and demonstrates excellent reproducibility.

Unprecedented non-aromatic, conformationally locked dibenzohexaphyrin analogs carrying multiple meso-exocyclic double bonds

Acid-catalysed, '3+3' condensation of m-bispyrryl benzene derivatives with acetone afforded new non-aromatic macrocycles that can be converted to meso-alkylidenyl dibenzohexaphyrins carrying four exocyclic double bonds at meso-positions by DDQ oxidation.

High-resolution impedance manometry facilitates assessment of pharyngeal residue and oropharyngeal dysphagic mechanisms

The utility of high-resolution impedance manometry (HRIM) for evaluating oropharyngeal dysphagia (OPD) has been investigated. These approaches are limited because of the sophisticated methodology. A method of transforming HRIM into a simple and useful diagnostic tool for evaluating OPD is needed. A videofluoroscopic swallowing study (VFSS) and HRIM were performed by independent blinded examiners in 26 consecutive healthy volunteers (12 men; median age, 56.5 years) and 10 OPD patients (five men; median age, 59.5 years). Upper esophageal sphincter (UES) relaxation parameters were measured using a standard HRIM protocol. Peristalsis and bolus transit of the pharyngoesophageal (PE) segment were assessed using an HRIM-modified protocol in which the catheter was pulled back 10 cm. PE bolus transits were evaluated with an impedance contour pattern (linear vs. stasis) method. A significant difference was observed between the manometric measures of healthy volunteers and OPD patients for only the duration of pharyngeal contraction (0.49 ± 0.19 vs. 0.76 ± 0.33 s, P = 0.04). The percentage agreement and kappa value for detecting pharyngeal residue between the VFSS and the impedance analysis were 100% and 1.00, respectively. HRIM allowed for comprehensive assessment of abnormal pharyngeal components that caused pharyngeal residue on VFSS in two patients; reduced base of the tongue versus weak pharyngeal contraction in one, and reduced relaxation of the UES versus reduced laryngeal elevation in the remaining patient. Our findings demonstrated that HRIM using a simple methodology (i.e., pull-back of the catheter) detected pharyngeal residue through a simple analysis of the impedance contour pattern (linear vs. stasis). Furthermore, HRIM facilitated a comprehensive assessment of OPD mechanisms and recognition of subtle abnormalities not yet visible to the naked eye on VFSS.

Enhanced performance in inverted polymer solar cells with D-π-A-type molecular dye incorporated on ZnO buffer layer

We report the superior characteristics of a ZnO buffer layer covered with a phenothiazine-based, π-conjugated donor-acceptor (D-π-A)-type organic dye (called "d-ZnO"). The use of this system for the performance enhancement of inverted bulk heterojunction polymer solar cells (PSCs) with the configuration of indium tin oxide/d-ZnO/polymer:PC71 BM/MoO3 /Ag (PC71 BM=[6,6]-phenyl C71 butyric acid methyl ester) is investigated. The layer of organic dyes anchored on the ZnO surface through carboxylate bonding reduces the shunt path on bare ZnO surface and provides better interfacial contacts and energy level alignments between the ZnO layer and the photoactive layer. This phenomenon consequently leads to highly enhanced photovoltaic parameters (fill factor, open-circuit voltage, and short-circuit current density) and power conversion efficiencies (PCEs). Inverted solar cells containing the d-ZnO layer not only revealed about 34% (PCE: 4.37%) and 18% (PCE: 7.11%) improvement in the PCEs of the representative poly-3(hexylthiophene) (P3HT) and low-band-gap poly{[4,8-bis-(2-ethyl-hexyl-thiophene-5-yl)-benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-alt-[2-(2'-ethylhexanoyl)-thieno[3,4-b]thiophen-4,6-diyl]} (PBDTTT-C-T) polymer systems, respectively, but also showed 2-4 times longer device lifetimes than their counterparts without the organic dye layer. These results demonstrate that this simple approach used in inverted PSCs with a metal oxide buffer layer could become a promising procedure to fabricate highly efficient and stable PSCs.

A rare case of interparietal incisional hernia from 8 mm trocar site after robot-assisted laparoscopic prostatectomy

Trocar site hernia arising from 8 mm robotic port is very rare despite the increasing prevalence of robot-assisted surgeries. To date, there had been only a single case reported in the literature. We report a case of small bowel obstruction secondary to an interparietal trocar site incisional hernia after robot-assisted laparoscopic prostatectomy. Meticulous closure of 8 mm robotic trocar sites associated with large peritoneal defect at the end of surgery should be performed.

International consensus on (ICON) pediatric asthma

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.

Prevalence of atopy and allergic diseases in Korean children: associations with a farming environment and rural lifestyle

BACKGROUND

The results of recent studies suggest that factors in rural environments may protect against the development of allergic diseases, but the underlying mechanisms are not well understood. The aim of this study was to investigate the prevalence of allergic diseases, to establish if this prevalence is influenced by migration from rural to urban areas and to identify environmental risk factors associated with these diseases.

METHODS

A cross-sectional study of children aged 9-12 years from a rural village, a rural town and an urban city in Korea was conducted. Demographic and disease-related information was obtained via a detailed questionnaire, and skin prick tests were performed.

RESULTS

There were significant differences in lifestyle and environmental factors between children from the rural village, the rural town and the urban children. The prevalence of allergic diseases and atopy was higher in urban children. A lower prevalence of allergic diseases and atopy was associated with farming parents, contact with farm animals during pregnancy, owning pets or a stable, breast-feeding and having older siblings. A comparison of rural village and rural town children revealed no evidence of an association of allergic diseases and atopy with farming parents, contact with farm animals during pregnancy or owning a stable. On the other hand, having older siblings and antibiotic use during infancy were significantly associated with allergic diseases and atopy in these children.

CONCLUSIONS

Protective factors associated with a farming environment and/or rural lifestyle may influence the prevalence of allergic diseases and atopy in Korean children.