The present survey was undertaken to observe the geographical distribution of metacercaria among the sweetfish, Plecoglossus altivelis, the most important second intermediate host of Metagonimus yokogawai, which were collected during the period from 1983 to 1984 in south-eastern coastal areas of Korea. The results obtained were summarized as follows: A total of 668 sweetfish collected from 70 chons (=streams) in the above coasta1 areas was examined for the metacercariae, and 432(64.7 percent) among them were infected with metacercariae of M. yokogawai. The mean number of metacercariae in a fish was in the range from 0 to 29,604 and the mean number of the metacercariae in a fish was 640.3. It was observed that the mean infection rate showed 46.4 percent in Gangweon-Do (=province). The infection rates varied from stream to stream showing 100 percent in Namdae stream(Gangnun-city), Obsib-stream(Samchok-gun) and Dongmak, 95.0 percent in Hosan stream, 90.0 percent in Gungchon stream, and Namdae stream (Yangyang-up), 80.0 percent in Hwasang stream, 50.0 percent in Daebong stream, 45.0 percent in Yonghwa stream, 30.0 percent in Sangchon stream and Sachon stream, 20.0 percent in Munam stream and Okgyoe stream, 15.0 percent in Imweon stream, 10.0 percent in Namchon stream. And no metacercarial infections in their fish host were found in the areas of Mulchi stream, Sangun stream, Gosamun stream, Jonchon stream snd Gagok stream. It was observed that the mean infection rate showed 50.9 percent in Kyongsangbuk-Do(=province). The infection rates also varied from stream to stream showing 100 percent in Songchon stream, Osib stream (Yongdok-gun) and Daejong stream, 60.0 percent in Pyonghae stream snd Gunmu stream, 50.0 percent in Buhwung stream, 25.0 percent in Nagok stream, 20.0 percent in Oangbi stream, 10.0 percent in Namhodong stream. And no metacercarial infections in their fish host were found in the areas of Namdae stream (Uljinup) and Choksan stream. It was observed that the mean infection rate showed 67.6 percent in Kyongsangnam-Do(=province). The infection rates varied from stream to stream showing 100 percent in Taehwa river, Hwiya river, Inchon stream, Miryang river, Nam river, Hwagae stream, Koha stream, Sosang stream, and Tongchon stream, 90.9 percent in Yoncho stream, 90.0 percent in Hoihwa stream, 80.0 percent in Chindong stream, 66.7 percent in Chingyo stream, 40.0 percent in Hoyam river. And no metacercarial infections in their fish host were found in the areas of Chinjon stream, Sanchon stream and Jukchon stream. It was observed that the mean infection rate showed 94.6 percent in Chollanam-Do(=province). The infection rates varied from stream to stream showing 100 percent in Dongchon stream, Isachon stream, Somjin river (Goksong-gun), Somjin river (Kurye-gun), Sosi stream, Gokchon stream, Kohung stream, Kwansan stream, Youi stream, Unjon stream and Apnae stream, 92.3 percent in Tamjin river, 90.9 percent in Okkok stream, 84.6 percent in Songgun stream. And no metacercarial infections in their fish host were found in the area of Yongok stream. On the other hand, the infection rate showed 100 percent in Inchon river of Chollabuk-Do (=province) and Kangon stream of Cheju-Do (=province).
parasitology-helminth-trematoda ; Metagonimus yokogawai ; epidemiology ; Plecoglossus altivelis

Parkinson’s disease (PD) is characterized by the presence of α-synuclein (α-syn) inclusions in the brain and the degeneration of dopamine-producing neurons. There is evidence to suggest that the progression of PD may be due to the prion-like spread of α-syn aggregates, so understanding and limiting α-syn propagation is a key area of research for developing PD treatments. Several cellular and animal model systems have been established to monitor α-syn aggregation and propagation. In this study, we developed an in vitro model using A53T α-syn-EGFP overexpressing SH-SY5Y cells and validated its usefulness for high-throughput screening of potential therapeutic targets. Treatment with preformed recombinant α-syn fibrils induced the formation of aggregation puncta of A53T α-syn-EGFP in these cells, which were analyzed using four indices: number of dots per cell, size of dots, intensity of dots, and percentage of cells containing aggregation puncta. Four indices are reliable indicators of the effectiveness of interventions against α-syn propagation in a one-day treatment model to minimize the screening time. This simple and efficient in vitro model system can be used for high-throughput screening to discover new targets for inhibiting α-syn propagation.

Background: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are significant public health issues in the world, but the epidemiological data pertaining to HAP/VAP is limited in Korea. The objective of this study was to investigate the characteristics, management, and clinical outcomes of HAP/VAP in Korea. Methods: This study is a multicenter retrospective cohort study. In total, 206,372 adult patients, who were hospitalized at one of the 13 participating tertiary hospitals in Korea, were screened for eligibility during the six-month study period. Among them, we included patients who were diagnosed with HAP/VAP based on the Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) definition for HAP/VAP. Results: Using the IDSA/ATS diagnostic criteria, 526 patients were identified as HAP/VAP patients. Among them, 27.9% were diagnosed at the intensive care unit (ICU). The cohort of patients had a median age of 71.0 (range from 62.0 to 79.0) years. Most of the patients had a high risk of aspiration (63.3%). The pathogen involved was identified in 211 patients (40.1%). Furthermore, multidrug resistant (MDR) pathogens were isolated in 138 patients; the most common MDR pathogen was Acinetobacter baumannii. During hospitalization, 107 patients with HAP (28.2%) had to be admitted to the ICU for additional care. The hospital mortality rate was 28.1% in the cohort of this study. Among the 378 patients who survived, 54.2% were discharged and sent back home, while 45.8% were transferred to other hospitals or facilities. Conclusion This study found that the prevalence of HAP/VAP in adult hospitalized patients in Korea was 2.54/1,000 patients. In tertiary hospitals in Korea, patients with HAP/VAP were elderly and had a risk of aspiration, so they were often referred to step-down centers.

Background: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are significant public health issues in the world, but the epidemiological data pertaining to HAP/VAP is limited in Korea. The objective of this study was to investigate the characteristics, management, and clinical outcomes of HAP/VAP in Korea. Methods: This study is a multicenter retrospective cohort study. In total, 206,372 adult patients, who were hospitalized at one of the 13 participating tertiary hospitals in Korea, were screened for eligibility during the six-month study period. Among them, we included patients who were diagnosed with HAP/VAP based on the Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) definition for HAP/VAP. Results: Using the IDSA/ATS diagnostic criteria, 526 patients were identified as HAP/VAP patients. Among them, 27.9% were diagnosed at the intensive care unit (ICU). The cohort of patients had a median age of 71.0 (range from 62.0 to 79.0) years. Most of the patients had a high risk of aspiration (63.3%). The pathogen involved was identified in 211 patients (40.1%). Furthermore, multidrug resistant (MDR) pathogens were isolated in 138 patients; the most common MDR pathogen was Acinetobacter baumannii. During hospitalization, 107 patients with HAP (28.2%) had to be admitted to the ICU for additional care. The hospital mortality rate was 28.1% in the cohort of this study. Among the 378 patients who survived, 54.2% were discharged and sent back home, while 45.8% were transferred to other hospitals or facilities. Conclusion This study found that the prevalence of HAP/VAP in adult hospitalized patients in Korea was 2.54/1,000 patients. In tertiary hospitals in Korea, patients with HAP/VAP were elderly and had a risk of aspiration, so they were often referred to step-down centers.

Background/Aims: Most studies on hospital-acquired pneumonia (HAP) have been conducted in intensive care unit (ICU) settings. This study aimed to investigate the microbiological and clinical characteristics of non-ICU-acquired pneumonia (NIAP) and to identify the factors affecting clinical outcomes in Korea. Methods: This multicenter retrospective cohort study was conducted in patients admitted to 13 tertiary hospitals between July 1, 2019 and December 31, 2019. Patients diagnosed with NIAP were included in this study. To assess the prognostic factors of NIAP, the study population was classified into treatment success and failure groups. Results: Of 526 patients with HAP, 379 were diagnosed with NIAP. Overall, the identified causative pathogen rate was 34.6% in the study population. Among the isolated organisms (n = 113), gram-negative bacilli were common pathogens (n = 91), such as Pseudomonas aeruginosa (n = 25), Acinetobacter baumannii (n = 23), and Klebsiella pneumoniae (n = 21). The multidrug resistance rates of A. baumannii, P. aeruginosa, and K. pneumoniae were 91.3%, 76.0%, and 57.1%, respectively. Treatment failure was significantly associated with K. pneumoniae (odds ratio [OR], 3.50; 95% confidence interval [CI], 1.35 to 9.05; p = 0.010), respiratory viruses (OR, 3.81; 95% CI, 1.34 to 10.82; p = 0.012), hematological malignancies (OR, 3.54; 95% CI, 1.57 to 8.00; p = 0.002), and adjunctive corticosteroid treatment (OR, 2.40; 95% CI, 1.27 to 4.52; p = 0.007). Conclusions The causative pathogens of NIAP in Korea are predominantly gram-negative bacilli with a high rate of multidrug resistance. These were not different from the common pathogens of ICU-acquired pneumonia.

Background: There is insufficient data on the benefits of empiric antibiotic combinations for hospital-acquired pneumonia (HAP). We aimed to investigate whether empiric antipseudomonal combination therapy with fluoroquinolones decreases mortality in patients with HAP. Methods: This multicenter, retrospective cohort study included adult patients admitted to 16 tertiary and general hospitals in Korea between January 1 and December 31, 2019.Patients with risk factors for combination therapy were divided into anti-pseudomonal non-carbapenem β-lactam monotherapy and fluoroquinolone combination therapy groups.Primary outcome was 30-day mortality. Propensity score matching (PSM) was used to reduce selection bias. Results: In total, 631 patients with HAP were enrolled. Monotherapy was prescribed in 54.7% (n = 345) of the patients, and combination therapy was prescribed in 45.3% (n = 286).There was no significant difference in 30-day mortality between the two groups (16.8% vs.18.2%, P = 0.729) or even after the PSM (17.5% vs. 18.2%, P = 0.913). After the PSM, adjusted hazard ratio for 30-day mortality from the combination therapy was 1.646 (95% confidence interval, 0.782–3.461; P = 0.189) in the Cox proportional hazards model. Moreover, there was no significant difference in the appropriateness of initial empiric antibiotics between the two groups (55.0% vs. 56.8%, P = 0.898). The proportion of multidrug-resistant (MDR) pathogens was high in both groups. Conclusion Empiric anti-pseudomonal fluoroquinolone combination therapy showed no survival benefit compared to β-lactam monotherapy in patients with HAP. Caution is needed regarding the routine combination of fluoroquinolones in the empiric treatment of HAP patients with a high risk of MDR.