Associations of particulate matter with atopic dermatitis and chronic inflammatory skin diseases in South Korea.

BACKGROUND: Particulate matter (PM) is a mixture of solid and liquid particles suspended in air, which originates from industrial plants or vehicle emissions. Although the skin is the primary body area of contact with air pollutants, the associations between PM and chronic inflammatory skin diseases has not been well established. AIM: To investigate associations between PM and atopic dermatitis (AD) and between PM and other chronic inflammatory dermatoses, using data from the Korean Health Insurance Review and Assessment Service. METHODS: Monthly disease statistics from the seven largest cities in South Korea (Seoul, Busan, Daegu, Incheon, Gwangju, Daejeon, Ulsan) and from Jeju Island (in total, a population of 23 288 000 for all eight areas) were included. Based on daily air pollution level and weather forecast from 2015 to 2019, multivariate negative binomial regression analysis was conducted to estimate monthly visits of AD with respect to outdoor air pollutants: coarse PM with a diameter of ≤ 10 µm (PM10) and fine PM with a diameter of ≤ 2.5 µm (PM2.5) ozone (O3 ), nitrogen dioxide (NO2 ), sulphur dioxide (SO2 ) and carbon monoxide (CO). RESULTS: Increases in the levels of PM2.5, PM10, SO2 and CO were associated with significant increases in monthly patient visits for AD. Every 10 µg/m3 increase in PM2.5 and PM10 resulted in patient visit increases of 2.71% (95% CI 0.76-4.71; P < 0.01) and 2.01% (95% CI 0.92-3.11, P < 0.001), respectively, while every 1 part per billion (ppb) increase in SO2 and every 100 ppb increase in CO resulted in visit increases of 2.26% (95% CI 1.35-3.17; P < 0.001) and 2.86% (95% CI 1.35-4.40; P < 0.001), respectively. O3 and NO2 were not associated with increased patient visits for AD. Increases in PM2.5 and PM10 concentrations were also significantly associated with increases in patient visits for psoriasis, seborrhoeic dermatitis and rosacea. CONCLUSION: Our data suggest that PM is associated with AD and other chronic inflammatory skin diseases.

Association between time to treatment and functional outcomes according to the Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score in endovascular stroke therapy.

BACKGROUND AND PURPOSE: The rate at which the chance of a good outcome of endovascular stroke therapy (EVT) decays with time when eligible patients are selected by baseline diffusion-weighted magnetic resonance imaging (DWI-MRI) and whether ischaemic core size affects this rate remain to be investigated. METHODS: This study analyses a prospective multicentre registry of stroke patients treated with EVT based on pretreatment DWI-MRI that was categorized into three groups: small [Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS)] (8-10), moderate (5-7) and large (<5) cores. The main outcome was a good outcome at 90 days (modified Rankin Scale 0-2). The interaction between onset-to-groin puncture time (OTP) and DWI-ASPECTS categories regarding functional outcomes was investigated. RESULTS: Ultimately, 985 patients (age 69 ± 11 years; male 55%) were analysed. Potential interaction effects between the DWI-ASPECTS categories and OTP on a good outcome at 90 days were observed (Pinteraction  = 0.06). Every 60-min delay in OTP was associated with a 16% reduced likelihood of a good outcome at 90 days amongst patients with large cores, although no associations were observed amongst patients with small to moderate cores. Interestingly, the adjusted rates of a good outcome at 90 days steeply declined between 65 and 213 min of OTP and then remained smooth throughout 24 h of OTP (Pnonlinearity  = 0.15). CONCLUSIONS: Our study showed that the probability of a good outcome after EVT nonlinearly decreased, with a steeper decline at earlier OTP than at later OTP. Discrepant effects of OTP on functional outcomes by baseline DWI-ASPECTS categories were observed. Thus, different strategies for EVT based on time and ischaemic core size are warranted.

The cutoff value of ossification of posterior longitudinal ligament (OPLL) for early diagnosis of myelopathy using somatosensory evoked potential in cervical OPLL patients.

STUDY DESIGN: Retrospective study. OBJECTIVES: The objective of this study was to find out whether ossification of posterior longitudinal ligament (OPLL) characteristics, including size, shape and subtype, can be used to diagnose myelopathy using somatosensory evoked potential (SEP) in cervical OPLL patients. SETTING: Yonsei University College of Medicine, Seoul, Korea. METHODS: We retrospectively reviewed the medical records of 153 cervical OPLL patients who underwent SEP study. OPLL anterior-posterior (AP) diameter, area and involved longitudinal vertebral level were measured. OPLL was classified into subtypes according to longitudinal continuity and shape. Correlation analysis and receiver operating curve were used. RESULTS: Tibial SEP latency was significantly correlated with OPLL AP diameter (P=0.001), diameter occupying ratio (P=0.019), area (P=0.007), area occupying ratio (P=0.008), involved longitudinal vertebral level (P=0.028) and space available for the spinal cord (P=0.019). The cutoff values that were diagnostic for SEP prolongation suggesting myelopathy were 4.91 mm for OPLL AP diameter, 6.02 mm for space available for the spinal cord, 44.5% for diameter occupying ratio, 63.4 mm2 for area, 36.1% for area occupying ratio and level 2 for the involved longitudinal vertebral level. CONCLUSIONS: Our results revealed that tibial SEP latency was significantly correlated with OPLL size and suggested cutoff values of OPLL diameter (4.91 mm, 44.5%) and area (63.4 mm2, 36.1%) for early diagnosis of myelopathy. These results can help to establish treatment plans.

Enhanced bactericidal action of acidified sodium chlorite caused by the saturation of reactants.

AIMS: Factors affecting the antibacterial action of acidified sodium chlorite (ASC), a widely used disinfectant, have not been determined. This study investigated the significant factors suggesting efficient production method to maximize bactericidal action of ASC. METHODS AND RESULTS: The effects of (i) preparation procedures (total three methods); (ii) initial concentrations of reactants: sodium chlorite (SC) and citric acid (CTA) (up to maximum solubility of each reactant) and (iii) final pH values (3·0 and 2·5) to the bactericidal action of ASC were investigated with a fixed final concentration of SC (10 ppm) using various foodborne pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium and Staphylococcus aureus). The antimicrobial compounds produced and the bactericidal effects depended on the preparation procedure and the initial concentrations of the reactants. The ASC prepared by premixing highly concentrated reactants (in particular > 40%) followed by dilution (dilution after reaction, DAR) was more effective in inactivating foodborne pathogens, and it produced higher antimicrobial compound (Cl(2) and ClO(2)) yields than the other procedures. A 5-min treatment with ASC, produced using the other procedures, resulted in a reduction of < 3·5 log CFU ml(-1) (Gram positive = 0·18-0·78; Gram negative = 0·03-3·49 log CFU ml(-1)), whereas ASC produced with the DAR procedure using the saturated reactants completely inactivated all of the test pathogens within 5 min without recovery (initial concentration = 6·94-7·08 log CFU ml(-1)). CONCLUSION: The ASC production with the DAR procedure using the saturated reactants maximizes both the antimicrobial compound yields and bactericidal effects of the ASC solutions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study will contribute to increase the efficiency of ASC treatments for disinfections reducing the effective SC concentrations for industrial use.

Assessment of post-stroke extrapersonal neglect using a three-dimensional immersive virtual street crossing program.

OBJECTIVE: To investigate the potential of our newly developed three-dimensional immersive virtual reality (VR) program modeled on a real street crossing as an assessment tool for extrapersonal neglect in stroke patients. METHODS: Thirty-two patients with right-hemispheric stroke (neglect group, 16; non-neglect group, 16) were enrolled. The deviation angle, reaction time, left-to-right reaction time ratio, visual and auditory cue rates, and failure rate were evaluated during missions to keep a virtual avatar safe from a traffic accident in the VR program. The line bisection test and letter cancellation test were also evaluated. RESULTS: The deviation angle, left-to-right reaction time ratio, left visual and auditory cue rates and left failure rate in the VR program showed significant differences between the two groups (P < 0.05). Depending on the direction of approach of the virtual car, the left parameters were significantly higher than the right parameters in the neglect group (P < 0.05). In the neglect group, the line bisection test correlated significantly with the deviation angle (P < 0.05). None of the other virtual reality parameters significantly correlated with the paper and pencil tests. CONCLUSION: Post-stroke neglect in the extrapersonal space can be easily and safely detected and measured using our three-dimensional immersive virtual street crossing program.

Terahertz transmission properties of an individual slit in a thin metallic plate.

We report on the terahertz transmission properties through a single slit in a thin metallic film. The properties are studied by comparing the transmissions of TE- and TM-polarized electromagnetic waves over a broad spectral range from the geometrical regime to the subwavelength limit. In the geometrical regime, the remarkable terahertz transmission due to guided modes is observed even without the contribution of surface waves. Whereas in the subwavelength limit, the surface charge oscillations associated with the TM-polarized guided mode give rise to strong transmission enhancement. The nature of the mechanisms for the terahertz transmission is elucidated using theoretical simulations of the near-field distributions and electromagnetic energy flow.

Cytokine production and modulation: comparison of patients with chronic fatigue syndrome and normal controls.

We studied cytokine production in 15 patients with chronic fatigue syndrome (CFS) and 23 controls. CFS patients' peripheral blood mononuclear cells were cultured with lipopolysaccharide or phytohemagglutinin. Enzymatic immunoassay indicated cytokine concentration in culture supernatants. CFS patients showed significantly lower mRNA levels and transforming growth factor-beta1 (TGF-beta1) production. Cytokine dysregulation affects CFS pathogenesis. TGF-beta1 may aid treatment because it affects CFS inflammatory characteristics.

Increased lysophosphatidylcholine content induced by thrombin receptor stimulation in adult rabbit cardiac ventricular myocytes.

OBJECTIVE: The aims were (1) to determine whether thrombin, which is increased in the presence of coronary thrombosis, can directly stimulate the production of lysophosphatidylcholine, which has arrhythmogenic properties, in ventricular myocytes; (2) whether the effect is dependent upon extracellular [Ca2+]; and (3) whether it is mediated directly through stimulation of the thrombin receptor. METHODS: Lipids were extracted from isolated adult rabbit ventricular myocytes and lysophosphatidylcholine was isolated by HPLC and quantified using a recently developed radiometric assay employing 3H-acetic anhydride. RESULTS: Thrombin (0.05 U.ml-1) stimulation of ventricular myocytes resulted in a nearly sixfold increase in lysophosphatidylcholine levels [0.26(SEM 0.03) to 1.61(0.42) nmol.mg-1 protein] within 1 min. The increase in myocytic lysophosphatidylcholine content was prevented by preincubation of thrombin with the proteolytic site inhibitors phenyly-prolyl-arginyl-chloromethyl ketone (PPACK) and dansylarginine N-(3-ethyl-1,5-pentanediyl)amide. The increase in lysophosphatidylcholine content in response to thrombin was not present at an extracellular calcium concentration ([Ca2+)]o) = 500 microM, but was marked at a physiological level of [Ca2+]o = 1.8 mM. Stimulation of myocytes with the thrombin receptor activating peptide SFLLRNPNDKYEPF (100 microM for 1 min) resulted in a similar increase in lysophosphatidylcholine content [1.61(0.27) nmol.mg-1 protein]. CONCLUSIONS: The marked increase in lysophosphatidylcholine content in cardiac myocytes in response to thrombin has important implications as an arrhythmogenic mechanism during early myocardial ischaemia.

Neuroanatomical patterns of fos-like immunoreactivity induced by a palatable meal and meal-paired environment in saline- and naltrexone-treated rats.

Opioid antagonists block the positive hedonic response to food taste and are potent inhibitors of palatability-driven feeding. However, the specific brain regions within which opioid peptide secretion contributes to the maintenance of palatability-driven feeding have not been clearly established. In the present study, c-Fos immunohistochemistry was used to identify regions rostral to the hindbrain that display cellular activation in response to a palatable meal and the meal-paired environment. Further, it was determined whether any of the cellular responses could be prevented by pretreating animals with naltrexone. Twenty brain regions known to be involved in gustation, appetite and reward functions were examined. Ingestion of the palatable meal (3.0 g of 30% shortening, 20% sucrose and 50% powdered Purina rat chow) increased Fos-like immunoreactivity (FLI) in lateral hypothalamus (LH), ventral tegmentum (VTA) and medial preoptic area (MPOA), and decreased FLI in the habenula (Hab). The meal-paired environment increased FLI in the VTA and nucleus accumbens shell (NAC shell). Naltrexone (1.0 mg/kg, i.p.) did not block consumption of the small meal but did prevent all of the distinctive increases in FLI induced by the meal and meal-paired environment. Since naltrexone, alone, increased FLI in VTA, NAC shell, central amygdala (ceA) and laterodorsal bed nucleus of the stria terminalis (BSTLD), the blunting of ingestion reward by naltrexone may result from direct or transsynaptic activating effects on opponent neuronal activity within this highly interconnected set of structures that mediate and modulate reward.

Protection from 1-methyl-4-phenylpyridinium (MPP+) toxicity and stimulation of regrowth of MPP(+)-damaged dopaminergic fibers by treatment of mesencephalic cultures with EGF and basic FGF.

Several peptide growth factors can maintain survival or promote recovery of injured central neurons. In the present study, the effects of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on the toxicity produced by the dopaminergic neurotoxin, 1-methyl-4-phenylpyridinium (MPP+), were investigated in rat mesencephalic dopaminergic neurons in culture. High affinity [3H]DA uptake and morphometric analyses of tyrosine hydroxylase immunostained neurons were used to assess the extent of MPP+ toxicity, dopaminergic neuronal survival and growth of neurites. Consistent with previous reports, EGF and bFGF treatments stimulated neuritic outgrowth in dopaminergic neurons, increased DA uptake and enhanced their long-term survival in vitro. These growth factors also stimulated proliferation of astrocytes. The time course of EGF and bFGF effects on dopaminergic neurons coincided with the increase in glial cell density, suggesting that proliferation of glia mediates their trophic effects. Several findings from our study support this possibility. When MPP+ was applied to cultures at 4 days in vitro, before glial cells had proliferated, the damage to dopaminergic neurons was not affected by EGF or bFGF pretreatments. However, when cultures maintained in the presence of the growth factors for 10 days were exposed to MPP+, after they had become confluent with dividing glial cells, the MPP(+)-induced decreases in DA uptake and cell survival were significantly attenuated. Furthermore, when glial cell proliferation was inhibited by 5-fluoro-2'-deoxyuridine, the protective effects of EGF and bFGF against MPP+ toxicity were abolished. Continuous treatment of MPP(+)-exposed cultures with EGF or bFGF resulted in the stimulation of process regrowth of damaged dopaminergic neurons with concomitant recovery of DA uptake, suggesting that the injured neurons are able to respond to the trophic effects of EGF and bFGF. In summary, our study shows that the trophic effects of EGF and bFGF on mesencephalic dopaminergic neurons include protection from the toxicity produced by MPP+ and promotion of recovery of MPP(+)-damaged neurons. Stimulation of glial cell proliferation is necessary for these effects.

Differential effects of mu and kappa opioid antagonists on Fos-like immunoreactivity in extended amygdala.

It was previously reported that systemic administration of the nonselective opioid antagonist, naltrexone, induces Fos-like immunoreactivity (FLI) within the central nucleus of the amygdala (CeA), bed nucleus of the stria terminalis (lateral-dorsal division; BSTLD), nucleus accumbens shell (NACshell) and ventral tegmental area (VTA) of free-feeding rats. These findings suggest that cellular activity in these brain regions is subject to opioid-mediated inhibitory control under basal conditions. Considering the involvement of mesoaccumbens dopamine neurons and components of the 'extended amygdala' in motivated behavior and reward, it was hypothesized that the induction of c-Fos by naltrexone accounts for the motivational-affective consequences of opioid antagonism. In Experiment 1, naltrexone was administered intracerebroventricularly (i.c.v.; 100 microg) to determine whether results obtained in the prior immunohistochemical studies could be attributed to blockade of opioid receptors in brain as opposed to peripheral tissues that convey visceral sensory inputs to the CeA and BSTLD. Naltrexone produced a marked increase in FLI within the CeA and BSTLD, and a moderate increase in NACshell. In Experiment 2, the kappa opioid antagonist, nor-binaltorphimine (Nor-BNI; 20.0 microg, i.c.v.) reproduced the effect of naltrexone in BSTLD and CeA, suggesting that the induction of c-Fos in these two structures is a consequence of kappa receptor blockade. The selective mu antagonist, CTAP (2.0 microg, i.c.v.), reproduced the effect of naltrexone in NACshell, suggesting that the induction of c-Fos in this structure is a consequence of mu receptor blockade. The functional implications of these results are discussed in terms of the known functions of these brain regions and opioid receptor types, and the prior observation that chronic food restriction eliminates the FLI induced by naltrexone in CeA and BSTLD. It is suggested that tonic mu opioid-mediated inhibition in NACshell has a predisposing effect on goal-approach behavior in general while kappa opioid-mediated inhibition in CeA and BSTLD has a predisposing effect on palatability-driven feeding in particular. Finally, a possible relationship between food restriction-induced suppression of the kappa opioid mechanism in CeA/BSTLD, local CRH function, and sensitization of the neural substrate for incentive-motivating effects of abused drugs is discussed.

Neuroanatomical patterns of Fos-like immunoreactivity induced by naltrexone in food-restricted and ad libitum fed rats.

Chronic food restriction produces a variety of adaptive changes in physiology and behavior aimed at the preservation of energy homeostasis. The brain opioid system may be involved in the adaptation to food restriction since regional levels of opioid peptides, precursor mRNA, and receptor binding have previously been observed. In the present study, c-Fos immunohistochemistry was used to localize cells that are released from opioid-mediated inhibition by naltrexone under conditions of food restriction and ad libitum feeding. In the majority of hypothalamic and forebrain areas examined, Fos-like immunoreactivity (FLI) was higher in food-restricted rats regardless of injection treatment. This may reflect the persistent stress of underfeeding or the synchronizing effect of afternoon feeding on spontaneous c-fos mRNA expression in food-restricted rats. In two brain regions, bed nucleus of the stria terminalis (BNST) and central amygdala (CEA), naltrexone increased FLI in ad libitum fed rats, exclusively. This result suggests the presence of tonic opioid secretion under basal conditions that is suppressed by food restriction. Interestingly, work in other laboratories indicates that anorectic agents consistently increase FLI in BNST and CEA. In three brain regions--lateral (LH), dorsomedial (DMH) and arcuate hypothalamus (ARC)--naltrexone increased FLI in food-restricted rats, exclusively. This result suggests the presence of opioid secretion that is unique to the state of food restriction. The hypothalamic pattern of FLI is discussed in terms of NPY-opioid interactions that result from the ARC response to changes in circulating insulin, corticosterone and leptin levels during food restriction.

Epidermal growth factor-induced survival and proliferation of neuronal precursor cells from embryonic rat mesencephalon.

Neuronal and glial precursor cells were isolated from primary cultures of embryonic rat mesencephalon. The separation of precursor cells from the neurons was accomplished by the resuspension of the primary cells by trypsinization, followed by replating. This procedure resulted in the death of differentiated neurons and the survival of precursor cells. The survival and proliferation of the replated precursor cells required the presence of epidermal growth factor (EGF) in the culture medium. The precursor cells differentiated into neurons and astrocytes, as determined by immunocytochemical staining with antibodies to neuron specific enolase (NSE) and tau protein or glial fibrillary acidic protein (GFAP) respectively.

Theoretical analysis of the effect of cell recycling on recombinant cell fermentation processes.

A cell recycle system is studied for two-stage continuous fermentation. Cell recycle around the second stage provides higher cell concentrations than processes without recycle and a longer residence time of the cell, which is necessary for inducible products, especially in recombinant cell fermentation. Residence time distribution of the cell in the fermentor is important for the optimization of inducible products. The residence time distributions are studied for the cases with and without significant cell growth in the second stage. With cell growth in the second stage, three cases are considered. These are the cases of (1) zero residence time for two daughter cells after the cell division, (2) zero residence time of one daughter cell after the cell division and inherited residence time for the other daughter cell from the mother cell after the cell division, and (3) two daughter cells having the residence time of the mother cell after the cell division.

Dynamic tracking line: feasible tracking region of a robot in conveyor systems.

The concept of dynamic tracking line is proposed as the feasible tracking region for a robot in a robot-conveyor system, which takes the conveyor speed into consideration. This paper presents an effective method to find the dynamic tracking line in a robotic workcell. The maximum permissible line-speed which is a quantitative measure of the robot capability for conveyor tracking, is defined on the basis of the relation between the end effector speed and the bounds on the joint velocities, accelerations, and torques. This measure is derived in an analytic form using the parameterized dynamics and kinematics of the manipulator, and some of its properties are established mathematically. The problem of finding the dynamic tracking line is then formulated as a root-solving problem for a single-variable equation, and solved by the use of a simple numerical technique. Finally, numerical examples are presented to demonstrate the methodology and its applications in workspace specification.

Dynamic tracking line: feasible tracking region of a robot in conveyor systems.

The concept of dynamic tracking line is proposed as the feasible tracking region for a robot in a robot-conveyor system, which takes the conveyor speed into consideration. This paper presents an effective method to find the dynamic tracking line in a robotic workcell. The maximum permissible line-speed which is a quantitative measure of the robot capability for conveyor tracking, is defined on the basis of the relation between the end-effector speed and the bounds on the joint velocities, accelerations, and torques. This measure is derived in an analytic form using the parameterized dynamics and kinematics of the manipulator, and some of its properties are established mathematically. The problem of finding the dynamic tracking line is then formulated as a root-solving problem for a single-variable equation, and solved by the use of a simple numerical technique. Finally, numerical examples are presented to demonstrate the methodology and its applications in workspace specification.

Raman Staircase in Charge Transfer SERS at the Junction of Fusing Nanospheres.

We present a theoretical analysis of Raman intensities for a molecule that bridges a current carrying junction. Experimental data is used to estimate parameters for the theoretical model. The recently reported staircase of Raman intensities observed during the fusion of nanodumbbell is reproduced.

Complementary limiting factors of astaxanthin synthesis during photoautotrophic induction of Haematococcus pluvialis: C/N ratio and light intensity.

We investigated the effect of carbon/nitrogen (C/N) ratio on astaxanthin synthesis in Haematococcus pluvialis during photoautotrophic induction by continuous input of both CO(2)-air mixture and intense light. When H. pluvialis was induced by constant irradiance induction at 200 micromol photon m(-2) s(-1), there was a positive correlation with astaxanthin content and C/N ratio, which was similar to the case for heterotrophic induction. Lower C/N ratios did not retard Haematococcus encystment, but did increase culture biomass, resulting in a decrease in astaxanthin production because of light limitation. However, induction using variable irradiance showed that reduction of astaxanthin production at low C/N ratios was successfully overcome by simply increasing the light intensity from 200 to 300 micromol photon m(-2) s(-1) to overcome the light limitation. This resulted in a greatly enhanced astaxanthin synthesis in proportion to cell density in cultures with low C/N ratios. Our results indicate that light intensity is more critical than C/N ratio in astaxanthin production by H. pluvialis during photoautotrophic induction.

Pioglitazone, a synthetic ligand for PPARgamma, induces apoptosis in RB-deficient human colorectal cancer cells.

No published data are available about the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and the role of PPARgamma in retinoblastoma protein (RB)-deficient human colorectal cancer (CRC) cells (SNU-C4 and SNU-C2A). Our aim was to investigate whether PPARgamma is expressed in SNU-C4 and SNU-C2A cells and to elucidate possible molecular mechanisms underlying the effect of pioglitazone, a synthetic ligand for PPARgamma, on cell growth in these cell lines. RT-PCR and Western blot analysis showed that both human CRC cell lines expressed PPARgamma mRNA and protein. Pioglitazone inhibited the cell growth of both cell lines through G2/M phase block and apoptosis. In addition, pioglitazone caused a down-regulation of the X chromosome-linked inhibitor of apoptosis (XIAP), Bcl-2, and cyclooxygenase-2 (COX-2) under conditions leading to PPARgamma down-regulation. These results suggest that pioglitazone may have therapeutic relevance or significance in the treatment of human CRC, and the down-regulation of XIAP, Bcl-2, and COX-2 may contribute to pioglitazone-induced apoptosis in these and other RB-deficient cell lines and tumors.