Synergetic analysis of springtime air pollution episodes over Gwangju, Korea.

The characteristics of springtime aerosols, including their optical and microphysical properties, were analyzed for the months of March to May of 2009 in Gwangju (35.23°N, 126.84°E), Korea. A high Light Detection and Ranging (LIDAR)-derived aerosol depolarization ratio (δ) of 0.25±0.04 was determined on dust particles during the observation period. The Ångström exponent values of the 440-870nm wavelength pair (Å440-870) and single-scattering albedo at 675nm (Ω675) measured by a CIMEL sun/sky radiometer were 0.77±0.19 and 0.95±0.01, respectively. The elevated dust layers reached a maximum elevation of 4km above sea level. Anthropogenic/smoke particles that originated from highly populated/industrialized regions could be distinguished by their relatively smaller particle size (Å440-870 ranged between 1.33 and 1.36) and higher light-absorbing (Ω675 of 0.92±0.01) characteristics. These aerosols are mostly distributed at altitudes <1.2km. The root-mean-square deviation (RMSD) between the aerosol optical depth (AOD, τ) derived from LIDAR (τLIDAR) and from the CIMEL sun/sky radiometer (τCIMEL) varied with respect to the surface PM10 concentration. The RMSD between τLIDAR and τCIMEL was as low as 13% under lower PM10 concentration levels (<100µg/m3). In contrast, the RMSD between τLIDAR and τCIMEL increased three times (~31%) under high surface PM10 concentration levels (>100µg/m3). These results suggest that the accuracy of τLIDAR is influenced by specific atmospheric conditions, regardless of its uncertainty.

Lidar measurements of Raman scattering at ultraviolet wavelength from mineral dust over East Asia.

We developed a novel measurement channel that utilizes Raman scattering from silicon dioxide (SiO2) quartz at an ultraviolet wavelength (361 nm). The excitation of the Raman signals is done at the primary wavelength of 355 nm emitted from a lidar instrument. In combination with Raman signals from scattering from nitrogen molecules, we may infer the mineral-quartz-related backscatter coefficient. This technique thus allows us to identify in a comparably direct way the mineral quartz content in mixed pollution plumes that consist, e.g., of a mix of desert dust and urban pollution. We tested the channel for the complex situation of East Asian pollution. We find good agreement of the inferred mineral-quartz-related backscatter coefficient to results obtained with another mineral quartz channel which was operated at 546 nm (primary emission wavelength at 532 nm), the functionality of which has already been shown for a lidar system in Tsukuba (Japan). The advantage of the novel channel is that it provides a better signal-to-noise ratio because of the shorter measurement wavelength.

Vertically-resolved profiles of mass concentrations and particle backscatter coefficients of Asian dust plumes derived from lidar observations of silicon dioxide.

This study presents a method to retrieve vertically-resolved profiles of dust mass concentrations by analyzing Raman lidar signals of silicon dioxide (quartz) at 546nm. The observed particle plumes consisted of mixtures of East Asian dust with anthropogenic pollution. Our method for the first time allows for extracting the contribution of the aerosol component "pure dust" contained in the aerosol type "polluted dust". We also propose a method that uses OPAC (Optical Properties of Aerosols and Clouds) and the mass concentrations profiles of dust in order to derive profiles of backscatter coefficients of pure dust in mixed dust/pollution plumes. The mass concentration of silicon dioxide (quartz) in the atmosphere can be estimated from the backscatter coefficient of quartz. The mass concentration of dust is estimated by the weight percentage (38-77%) of mineral quartz in Asian dust. The retrieved dust mass concentrations are classified into water soluble, nucleation, accumulation, mineral-transported and coarse mode according to OPAC. The mass mixing ratio of 0.018, 0.033, 0.747, 0.130 and 0.072, respectively, is used. Dust extinction coefficients at 550nm were calculated by using OPAC and prescribed number concentrations for each of the 5 components. Dust backscatter coefficients were calculated from the dust extinction coefficients on the basis of a lidar ratio of 45±3sr at 532nm. We present results of quartz-Raman measurements carried out on the campus of the Gwangju Institute of Science and Technology (35.10°N, 126.53°E) on 15, 16, and 21 March 2010.

Iatrogenic left internal mammary artery to great cardiac vein anastomosis treated with coil embolization.

Inadvertent left internal mammary artery (LIMA)-great cardiac vein (GCV) anastomosis is a rare complication of coronary artery bypass graft surgery. Patients with iatrogenic aortocoronary fistula (ACF) were usually treated surgical repair, percutaneous embolic occlusion with coil or balloon. We report a case of iatrogenic LIMA to GCV anastomosis successfully treated with coil embolization and protected left main coronary intervention through the percutaneous transfemoral approach.

Prevalence and patterns of left ventricular dysfunction in patients with pheochromocytoma.

BACKGROUND: Excessive catecholamine release in pheochromocytoma is known to cause transient reversible left ventricular (LV) dysfunction, such as in the case of pheochromocytoma-associated catecholamine cardiomyopathy. We investigated patterns of clinical presentation and incidence of LV dysfunction in patients with pheochromocytoma. METHODS: From January 2004 to April 2011, consecutive patients with pheochromocytoma were retrospectively studied with clinical symptoms, serum catecholamine profiles, and radiologic findings. Patterns of electrocardiography and echocardiography were also analyzed. RESULTS: During the study period, a total of 36 patients (21 males, 49.8 ± 15.8 years, range 14-81 years) with pheochromocytoma were included. In the electrocardiographic examinations, normal findings were the most common findings (19, 52.8%). LV hypertrophy in 12 cases (33.3%), sinus tachycardia in 3 (8.3%), ischemic pattern in 1 (2.8%) and supraventricular tachycardia in 1 (2.8%). Echocardiographic exam was done in 29 patients (80.6%). Eighteen patients (62.1%) showed normal finding, 8 (27.6%) revealed concentric LV hypertrophy with normal LV systolic function, and 3 (10.3%) demonstrate LV systolic dysfunction (LV ejection fraction < 50%). Three showed transient LV dysfunction (2 with inverted Takotsubo-type cardiomyopathy and 1 with a diffuse hypokinesia pattern). Common presenting symptoms in the 3 cases were new onset chest discomfort and dyspnea which were not common in the other patients. Their echocardiographic abnormalities were normalized with conventional treatment within 3 days. CONCLUSION: Out of total 36 patients with pheochromocytoma, 3 showed transient LV systolic dysfunction (catecholamine cardiomyopathy). Pheochromocytoma should be included as one of possible causes of transient LV systolic dysfunction.

A Case of Acute ST-Segment Elevation Myocardial Infarction Mimicking Stress Induced Cardiomyopathy; Demonstration of Typical Echocardiographic Finding Correlated with Unusual Distribution of Left Anterior Descending Coronary Artery.

Stress-induced cardiomyopathy (SCMP) is diagnosed in 1-2% of patients presenting with symptoms suggestive of acute coronary syndrome. Because of sharing many common clinical features with SCMP, acute ST-segment elevation myocardial infarction (STEMI) can be misdiagnosed as SCMP. However, it can be associated with fatal outcome of the patient. Also, diagnosis of SCMP seems to be always challenging to clinicians, especially in the decision of taking coronary angiography which is still invasive and even risky. Here, we present a case with acute STEMI mimicking SCMP as a result of anatomical variation of coronary circulation. In this patient, prompt and early coronary angiography and stent implantation was very helpful.

A Case with Upper Extremity Deep Vein Thrombosis after in vitro Fertilization.

Deep vein thrombosis (DVT) is a predisposing condition of pulmonary embolism which can be fatal. Usually, DVT is found in the lower extremities. However, DVT can be occurred in the upper extremities. The usual predisposing conditions of the upper extremity DVT include insertion of central venous catheters and pacemaker wires. Here, we report a case of upper extremity DVT after in vitro fertilization and embryo transfer. The patient was successfully controlled with subcutaneous administration of low molecular weight heparin.