Establishment of particulate matterinduced lung injury model in mouse / 한국실험동물학회지

Background@#Particulate matter (PM) is one of the principal causes of human respiratory disabilities resulting from air pollution. Animal models have been applied to discover preventive and therapeutic drugs for lung diseases caused by PM. However, the induced severity of lung injury in animal models using PM varies from study to study due to disparities in the preparation of PM, and the route and number of PM administrations. In this study, we established an in vivo model to evaluate PM-induced lung injury in mice. @*Results@#PM dispersion was prepared using SRM2975. Reactive oxygen species were increased in MLE 12 cells exposed to this PM dispersion. In vivo studies were conducted in the PM single challenge model, PM multiple challenge model, and PM challenge with ovalbumin-induced asthma using the PM dispersion. No histopathological changes were observed in lung tissues after a single injection of PM, whereas mild to moderate lung inflammation was obtained in the lungs of mice exposed to PM three times. However, fibrotic changes were barely seen, even though transmission electron microscopy (TEM) studies revealed the presence of PM particles in the alveolar macrophages and alveolar capillaries. In the OVA-PM model, peribronchial inflammation and mucous hypersecretion were more severe in the OVA+PM group than the OVA group. Serum IgE levels tended to increase in OVA+PM group than in OVA group. @*Conclusions@#In this study, we established a PM-induced lung injury model to examine the lung damage induced by PM. Based on our results, repeated exposures of PM are necessary to induce lung inflammation by PM alone. PM challenge, in the presence of underlying diseases such as asthma, can also be an appropriate model for studying the health effect of PM.

Establishment of particulate matterinduced lung injury model in mouse / 한국실험동물학회지

Background@#Particulate matter (PM) is one of the principal causes of human respiratory disabilities resulting from air pollution. Animal models have been applied to discover preventive and therapeutic drugs for lung diseases caused by PM. However, the induced severity of lung injury in animal models using PM varies from study to study due to disparities in the preparation of PM, and the route and number of PM administrations. In this study, we established an in vivo model to evaluate PM-induced lung injury in mice. @*Results@#PM dispersion was prepared using SRM2975. Reactive oxygen species were increased in MLE 12 cells exposed to this PM dispersion. In vivo studies were conducted in the PM single challenge model, PM multiple challenge model, and PM challenge with ovalbumin-induced asthma using the PM dispersion. No histopathological changes were observed in lung tissues after a single injection of PM, whereas mild to moderate lung inflammation was obtained in the lungs of mice exposed to PM three times. However, fibrotic changes were barely seen, even though transmission electron microscopy (TEM) studies revealed the presence of PM particles in the alveolar macrophages and alveolar capillaries. In the OVA-PM model, peribronchial inflammation and mucous hypersecretion were more severe in the OVA+PM group than the OVA group. Serum IgE levels tended to increase in OVA+PM group than in OVA group. @*Conclusions@#In this study, we established a PM-induced lung injury model to examine the lung damage induced by PM. Based on our results, repeated exposures of PM are necessary to induce lung inflammation by PM alone. PM challenge, in the presence of underlying diseases such as asthma, can also be an appropriate model for studying the health effect of PM.

Enrichment of Short-Chain Ceramides and Free Fatty Acids in the Skin Epidermis, Liver, and Kidneys of db/db Mice, a Type 2 Diabetes Mellitus Model

Patients with diabetes mellitus (DM) often suffer from diverse skin disorders, which might be attributable to skin barrier dysfunction. To explore the role of lipid alterations in the epidermis in DM skin disorders, we quantitated 49 lipids (34 ceramides, 14 free fatty acids (FFAs), and cholesterol) in the skin epidermis, liver, and kidneys of db/db mice, a Type 2 DM model, using UPLC-MS/MS. The expression of genes involved in lipid synthesis was also evaluated. With the full establishment of hyperglycemia at the age of 20 weeks, remarkable lipid enrichment was noted in the skin of the db/db mice, especially at the epidermis and subcutaneous fat bed. Prominent increases in the ceramides and FFAs (>3 fold) with short or medium chains (

Low-Dose Bisphenol A Increases Bile Duct Proliferation in Juvenile Rats: A Possible Evidence for Risk of Liver Cancer in the Exposed Population?

Increasing concern is being given to the association between risk of cancer and exposure to low-dose bisphenol A (BPA), especially in young-aged population. In this study, we investigated the effects of repeated oral treatment of low to high dose BPA in juvenile Sprague-Dawley rats. Exposing juvenile rats to BPA (0, 0.5, 5, 50, and 250 mg/kg oral gavage) from post-natal day 9 for 90 days resulted in higher food intakes and increased body weights in biphasic dose-effect relationship. Male mammary glands were atrophied at high dose, which coincided with sexual pre-maturation of females. Notably, proliferative changes with altered cell foci and focal inflammation were observed around bile ducts in the liver of all BPA-dosed groups in males, which achieved statistical significance from 0.5 mg/kg (ANOVA, Dunnett’s test, p<0.05). Toxicokinetic analysis revealed that systemic exposure to BPA was greater at early age (e.g., 210-fold in C(max), and 26-fold in AUC at 50 mg/kg in male on day 1 over day 90) and in females (e.g., 4-fold in C(max) and 1.6-fold in AUC at 50 mg/kg vs. male on day 1), which might have stemmed from either age- or gender-dependent differences in metabolic capacity. These results may serve as evidence for the association between risk of cancer and exposure to low-dose BPA, especially in young children, as well as for varying toxicity of xenobiotics in different age and gender groups.

Prospective Study on the Factors Related to Premature Infant's Development at Six-Months

PURPOSE: This study was conducted to monitor the development of Korean premature infant at six-month age and to explore factors related to developmental status of the premature infants. METHODS: Participants were 58 premature infants whose corrected age was six-months old and their mothers. The developmental states of infants were followed-up with the Korean Prescreening Developmental Questionnaire (KPDQ-II). Clinical characteristics of the infants were identified from the medical records. Other characteristics including Edinburgh Postnatal Depression Scale, husband's support, social support, and mother-infant attachment were assessed using self-report questionnaires from the mothers. RESULTS: Forty three percent of the infants were in the group of questionable status of development on the KPDQ-II. There were significant differences between the premature infants with normal developmental status and those with questionable developmental status depending on gender (χ2=5.03, p=.034), gestational age (t=2.59, p=.012), hospital stay (t=-2.08, p=.042), revised Neurobiologic Risk Score (t=-3.05, p=.004) and mother-infant attachment score (t=2.12, p=.040). CONCLUSION: Mother-infant attachment, as well as physiological state of premature infants, is an important variable in early development. Therefore, early monitoring for the development has to be done for physiologically vulnerable premature groups. Also, providing proper nursing support to improve maternal attachment needs to be considered.

The effect of on-line hemodiafiltration on heart rate variability in end-stage renal disease

BACKGROUND: The autonomic nervous system plays a central role in the maintenance of hemodynamic stability. Cardiac autonomic dysfunction may result in serious complications, such as sudden cardiac death. Heart rate variability (HRV) is sigificantly reduced in patients undergoing chronic hemodialysis (HD). The aim of this study was to evaluate the effect of on-line hemodiafiltration (OL-HDF) on the autonomic nervous system in chronic HD patients. METHODS: Forty chronic HD patients were prospectively studied. The participants were divided into conventional HD and OL-HDF groups. They received regular high-flux HD or OL-HDF for 4-hour sessions, three times a week. Time-and frequency-domain measures of the 24-hour HRV were analyzed during the interdialytic period prior to postdilution OL-HDF and every 6 months for 24 months. The 7-year survival was also evaluated. RESULTS: Among the 40 participants, 15 patients in the HD group and 11 patients in the OL-HDF group completed the study. There was no difference in the baseline characteristics. After 24 months of treatment, beta2-microglobulin concentration decreased (from 33.4 +/- 15.2 mg/dL to 28.4 +/- 6.2 mg/dL, P = 0.02) in the OL-HDF group, while there was no change in the HD group In the HRV analysis, the frequency-domain HRV parameters increased significantly compared with baseline in the OL-HDF group [natural logarithmic high frequency (lnHF), 3.15 +/- 3.36 ms2 vs. 4.42 +/- 3.81 ms2; ln low frequency (LF), 3.56 +/- 3.17 ms2 vs. 4.78 +/- 3.99 ms2; ln very low frequency (VLF), 4.90 +/- 4.62 ms2 vs. 6.38 +/- 5.54 ms2; LF/HF ratio, 1.4 +/- 0.4 vs. 2.5 +/- 0.1]. The survival rate was similar between the groups. CONCLUSION: This study shows that OL-HDF improved autonomic nervous system dysfunction in chronic HD patients.

Unusual Presentation Chronic Pulmonary Embolism due to Calcified Right Ventricular Mass

Cardiac calcified amorphous tumors (CATs) can arise in all four chambers of the heart. Cardiac CATs can cause diverse symptoms according to their locations, and mass or embolic effects. Pulmonary emboli arising from cardiac CATs have been reported, but the true incidence is unknown due to their rarity. Herein we report a rare case with diffuse CATs in the right ventricle which caused a calcific pulmonary embolism and right-sided heart failure. Echocardiography, chest non-contrast computed tomography, and cardiac magnetic resonance imaging helped us diagnose the CATs. We recommend the usefulness of a multimodality imaging approach to characterize intracardiac masses and their complications accurately.