Prognostic impact of suspicious extraabdominal lymph nodes on patient survival in advanced ovarian cancer.

OBJECTIVE: To evaluate the clinical impact of suspicious extra-abdominal lymph nodes (EALNs) identified preoperatively on CT and/or PET/CT images in advanced ovarian cancer. METHODS: A retrospective study was conducted with 122 patients diagnosed with stage III or IV ovarian cancer with preoperative CT and/or PET/CT images from 2006 to 2022. Imaging studies were evaluated for the presence, size and location of suspicious EALNs. Suspicious lymph node enlargement was defined by a cut-off ≥5mm short-axis dimension on CT and/or lesions with maximum standardized uptake values of ≥2.5 on PET/CT. This study only included patients who did not have their EALNs surgically removed. RESULTS: A total 109 patients met the inclusion criteria; 36 (33%) had suspicious EALNs and were categorized as "node-positive". The median overall survival (OS) was 45.73 months for the "node-positive" and 46.50 months for the "node-negative" patients (HR 1.17, 95% CI 0.68-2.00, p = 0.579). In multivariate analysis, after adjusting for other variables selected by process of backward elimination using a significance level of p<0.20, suspicious EALNs still showed no clinical significance on OS (aHR 1.20, 95% CI 0.67-2.13, p = 0.537) as well as progression-free survival (aHR 1.43, 95% CI 0.85-2.41, p = 0.174). Old age (aHR 2.23, 95% CI 1.28-3.89, p = 0.005) and platinum resistance (aHR 1.92, 95% CI 1.10-3.36, p = 0.023) affects adversely on OS. CONCLUSION: Suspicious EALNs did not worsen the prognosis of patients with advanced ovarian cancer. However, its impact on survival is not yet clarified. Further investigation is required to assess the clinical significance of suspicious EALNs on preoperative imaging studies.

Molecular Prevalence of Blastocystis sp. from Patients with Diarrhea in the Republic of Korea.

Blastocystis sp. is the most common intestinal protozoan affecting human health worldwide. Several studies have reported the prevalence of Blastocystis sp. in various regions of the Republic of Korea. However, limited data are available on the prevalence and subtype (ST) distribution of this parasite among regions. Therefore, we investigated the prevalence and ST distributions of this parasite in the Republic of Korea. For this purpose, 894 stool specimens were collected from patients with diarrhea and tested for the presence of Blastocystis sp. using PCR analysis. The isolates were subsequently subtyped. The overall prevalence was 11.6%. Of the 104 isolates, ST3 was the most prevalent, followed by ST1. Additionally, a single case of the rare subtype ST8 was identified, representing the first reported case in the Republic of Korea. The results suggested that the predominance of ST3 observed in this study reflects human-to-human transmission with low genetic diversity within the ST, while ST1 transmission is likely correlated with animals. In the future, to better understand Blastocystis sp. transmission dynamics, human, animal, and environmental factors should be studied from a "One Health" perspective.

Risk Factors and Prognosis of Stroke in Gynecologic Cancer Patients.

Increased life expectancy and cancer prevalence rates expose patients to a higher risk of developing other comorbidities such as stroke. This study aimed to evaluate the risk factors for and prognosis of stroke in patients with gynecological cancers. A single-center retrospective cohort study was conducted on patients with cervical, endometrial, and epithelial ovarian cancers. Patients were classified into three groups based on the period of stroke onset: at least one year before cancer diagnosis, within one year before cancer diagnosis to six months after the last treatment date, and six months after the last treatment date. Among the 644 patients, stroke occurred in 54 (8.4%). In univariate analysis, stroke was significantly associated with overall survival. In contrast, in multivariate analysis, stroke was significantly associated with age and hypertension, but not with overall survival. Age, pulmonary thromboembolism/deep vein thrombosis, histological grade, and tumor stage were significantly associated with overall survival. Therefore, it is important to establish an appropriate examination and treatment plan for patients with gynecologic cancers using a multidisciplinary approach that incorporates the patient's age, medical condition, and tumor characteristics rather than excessively considering the adverse effects of stroke on cancer prognosis.

Kudoa septempunctata Spores Cause Acute Gastroenteric Symptoms in Mouse and Musk Shrew Models as Evidenced In Vitro in Human Colon Cells.

Kudoa septempunctata is a myxosporean parasite that infects the trunk muscles of olive flounder (Paralichthys olivaceus) and has been reported to cause foodborne illnesses in humans. However, the molecular mechanisms underlying K. septempunctata spore toxicity remain largely unknown. In this study, the gastroenteropathy of K. septempunctata was examined in human colon adenocarcinoma cells as well as experimental mice inoculated with spores. We found that K. septempunctata decreased transepithelial resistance and disrupted epithelial tight junctions by deleting ZO-1 in Caco-2 monolayers. Additionally, serotonin (5-HT), an emetic neurotransmitter, was increased in K. septempunctata-inoculated cells. In vivo, K. septempunctata spores induced diarrhea in suckling mice (80% in ddY and 70% in ICR mice), with a minimum provocative dose of 2 × 105 K. septempunctata spores. In house musk shrews, K. septempunctata induced emesis within 1 h and induced serotonin secretion in the intestinal epithelium. In conclusion, K. septempunctata may induce diarrhea and emesis by increasing intestinal permeability and serotonin secretion.

Changes in Vitamin D Status in Korean Adults during the COVID-19 Pandemic.

The aim of this study was to investigate changes in 25(OH)D (25-hydroxyvitamin D) levels and in the vitamin D status of Korean adults before and during the coronavirus disease (COVID-19) pandemic. This study compared serum 25(OH)D levels before and after the pandemic in 1483 adults aged 19 years and older who were screened at a university hospital. Subjects were selected only from participants tested in the same season before and after the pandemic. The pre-COVID-19 testing period was from 1 March 2018 to 31 November 2019; the testing period in the COVID-19 era was from 1 June 2020 to 31 November 2021. The mean 25(OH)D level for all participants was 21.4 ± 10.2 ng/mL prior to the outbreak of COVID-19, which increased to 23.6 ± 11.8 ng/mL during the COVID-19 lockdown period (p < 0.001). The increase was particularly dramatic in elderly females (28.8 ± 12.3 ng/mL to 37.7 ± 18.6 ng/mL, p = 0.008). The prevalence of vitamin D deficiency decreased in both males (48.4% to 44.5%, p = 0.005) and females (57.0% to 46.0%, p < 0.001). In conclusion, 25(OH)D levels in Korean adults increased during the COVID-19 era, and the prevalence of vitamin D deficiency decreased accordingly.

Changes in the prevalence of metabolic syndrome in Korean adults after the COVID-19 outbreak.

OBJECTIVES: This study sought to reveal changes in the prevalence of metabolic syndrome (MetS) after the start of the coronavirus disease 2019 (COVID-19) pandemic and to identify the groups showing the greatest changes. METHODS: We compared the prevalence of MetS between 2017-2019 (i.e., the 3-year period before the COVID-19 pandemic) and soon after the initial outbreak of COVID-19 in 2020 among 24,564 adults ≥ 19 years of age using data from the Korea National Health and Nutrition Examination Survey. RESULTS: The prevalence of MetS increased steadily between 2017 and 2020 (29.4 to 35.3%, p for trend < 0.001), with annual percent changes of 2.0%p, 2.2%p, and 1.7%p, respectively. Compared to 3 years before the COVID-19 pandemic, the prevalence of MetS significantly increased during the COVID-19 pandemic in males (6.2%p; 95% confidence interval [CI], 3.5 to 8.9) compared to females (1.5%p; 95% CI, -1.2 to 4.1). The age groups with the greatest increases in MetS prevalence after the COVID-19 pandemic were those in their 40s (4.6%p; 95% CI, 0.9 to 8.4) and 50s (5.8%p; 95% CI, 2.2 to 9.4). By educational background, the increase in MetS prevalence was greatest among those with a college degree or higher (5.1%p). The prevalence of MetS in high-income (5.3%p) and low-income (4.6%p) groups significantly increased. CONCLUSIONS: The increasing trend in the overall prevalence of MetS continued during the COVID-19 pandemic. In particular, the prevalence of MetS among adult males in their 40s and 50s increased significantly after the COVID-19 outbreak in Korea.

Prenatally Ruptured Patent Urachus: A Case Report and Review of Literature.

Patent urachus is a type of urachal anomaly in which the urachus does not tail off but remains connected to the bladder in the umbilicus. The prevalence of patent urachus is very low. Herein, we report a case of patent urachus ruptured and exposed to amniotic fluid in utero. In this case, the size decreased after the second trimester, which was thought to be due to rupture in utero. After delivery, patent urachus was confirmed by inserting a foley catheter, which runs through a ruptured cyst on umbilical cord insertion. The day after delivery, the neonate underwent surgical excision of the urachal cyst and closing umbilicus. The mechanism of patent urachus rupture is unknown. As the fetus matures, it is thought that the higher intravesical pressure may affect the rupture of the cyst. Patent urachus could be ruptured in the uterus spontaneously, and surgical correction is needed. Therefore, prenatal differential diagnosis is important.

The risk of preterm birth in women with history of short cervix delivering at term in the previous pregnancy: a retrospective cohort study.

PURPOSE: To investigate whether women with a short cervical length (CL), but delivered at term in the first pregnancy might have increased risks of having short cervix and spontaneous preterm birth (sPTB) in the subsequent pregnancies. METHODS: This is a retrospective cohort study including singleton gestations who were delivered between Jan 2011 and Dec 2018, who had had one childbirth experience and who had transvaginal sonographic CL assessment performed at mid-trimester (18 ~ 30 weeks) in both pregnancy. The women were divided into four group according to the history of preterm birth and a short cervix (< 25 mm before 30 weeks of gestation): (1) the Preterm-short cervix group, (2) the Preterm-no shortening group, (3) the Term-short cervix group, and (4) the Term-no shortening group. We compared the risk of having short cervix and sPTB during the second pregnancy of women. Secondary outcomes were threatened preterm labor, need for tocolytics, and cerclage placement. RESULTS: A total of 804 women met our inclusion criteria. The rate of having short cervix (< 25 mm before 28 weeks of gestation) during the second pregnancy in women in the Term-short cervix group (43.2%) was significantly higher than those in women in the Term-no shortening group (6.6%), and in the Preterm-no shortening group (8.8%) (all p < 0.001 with Bonferroni correction), but not higher than those in women with the Preterm-short cervix group (30.8%, p > 0.05 with Bonferroni correction). When compared with women in the Preterm-no shortening group, women in the Term-short cervix group were also at an increased risk of need for need of tocolytics (60.2% vs. 26.5%) and cerclage placement (15.9% vs. 6.1%, all p < 0.001). Women in the Term-short cervix group had an increased risk of sPTB (< 37 weeks) during the second pregnancy, as compared to those in the Term-no shortening group (adjusted odds ratio 5.098, 95% CI 2.107-11.874). CONCLUSION: Women with a history of short cervix in their first pregnancy, but who delivered at term, were at increased risk of having a short cervix and sPTB in their second pregnancy, as compared to women with a history of term delivery without cervical shortening. Thus, short cervix of the previous pregnancy might be a predictive factors for preterm birth in the subsequent pregnancy.

First Identification and Genotyping of Enterocytozoon bieneusi and Prevalence of Encephalitozoon intestinalis in Patients with Acute Diarrhea in the Republic of Korea.

Encephalitozoon intestinalis and Enterocytozoon bieneusi can cause diarrhea in humans, especially severe diarrhea in immunocompromised patients. However, there have been few studies on Enc. intestinalis and Ent. bieneusi in patients with acute diarrhea in the Republic of Korea (ROK). In this study, fecal samples were collected from 1241 patients with acute diarrhea in 2020. Among these, 24 cases of Enc. intestinalis and one case of Ent. bieneusi were detected via PCR amplification of small subunit ribosomal RNA. Genotyping of the internal transcribed spacer region sequence revealed that the detected Ent. bieneusi genotype was in Group 1. This study provides the first evidence that Ent. bieneusi exists in humans in addition to animals in the ROK. To identify the causative agent, continuous monitoring of Enc. intestinalis and Ent. bieneusi is necessary for patients with acute diarrhea in the ROK.

Antibiotic resistance in shellfish and major inland pollution sources in the drainage basin of Kamak Bay, Republic of Korea.

Shellfish-growing areas in marine environments are affected by pollutants that mainly originate from land, including streams, domestic wastewater, and the effluents of wastewater treatment plants (WWTPs), which may function as reservoirs of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs). The objective of this study was to identify the occurrence and distribution of antibiotic resistance at five oyster sampling sites and 11 major inland pollution sources in the drainage basin of Kamak Bay, Republic of Korea. Culture-based methods were used to estimate the diversity and abundance of antibiotic-resistant Escherichia coli strains isolated from oysters and major inland pollution sources. The percentages of ARB and multiple antibiotic resistance index values were significantly high in discharge water from small fishing villages without WWTPs. However, the percentages of antibiotic-resistant E. coli isolates from oysters were low, as there was no impact from major inland pollutants. Fourteen ARGs were also quantified from oysters and major inland pollution sources. Although most ARGs except for quinolones were widely distributed in domestic wastewater discharge and effluent from WWTPs, macrolide resistance genes (ermB and msrA) were detected mainly from oysters in Kamak Bay. This study will aid in tracking the sources of antibiotic contamination in shellfish to determine the correlation between shellfish and inland pollution sources.

The degree of cervical length shortening as a predictor of successful or failed labor induction.

OBJECTIVE: To evaluate whether the degree of cervical length change was associated with successful cervical dilatation during labor induction. MATERIALS AND METHODS: We conducted a secondary analysis of a prospective observational study of term singleton pregnant women who underwent labor inductions. Cases of Cesarean section due to fetal distress or maternal request during the first stage of labor were excluded. The enrolled women were categorized into two groups according to achievement of full cervical dilatation. The cervical length near induction and cervical length shortening over the last four weeks of pregnancy were compared between the two groups. A receiver operating characteristics (ROC) analysis was performed to evaluate the screening performance for failed cervical dilatation during labor induction. RESULTS: A total of 165 women were enrolled for the final analysis; of these, 145 (87.9%) women reached the second stage of labor and 20 (12.1%) women failed to achieve full cervical dilatation. Women who failed to achieve full cervical dilatation had a significantly longer cervical length near induction and less cervical length change over previous four weeks compared with women who achieved full cervical dilatation (P = 0.018 and 0.005, respectively). Multivariate analysis showed that cervical length >29 mm (odds ratios [OR], 4.15; 95% confidence interval [CI], 1.290-13.374, P = 0.017) and cervical length shortening â‰¦ 6 mm (OR, 5.87; 95% CI, 1.552-22.271, P = 0.009) were significantly associated with failed cervical dilatation after adjusting for birthweight and previous history of vaginal delivery. Cervical length shortening alone provided a better prediction of failed cervical dilatation than the combination of cervical length and shortening (sensitivity, 76.9%; specificity, 63.8%). CONCLUSION: The probability of failed cervical dilatation during labor induction was significantly increased in cases when the cervical length was greater than 29 mm near induction or when the cervical length shortening was less than 6 mm over the last four weeks.

Combination of three-dimensional placental vascular indices and volume and uterine artery pulsatility index at 10-13 weeks of gestation could improve the prediction of adverse pregnancy outcomes.

AIM: To evaluate whether three-dimensional (3D) placental vascular indices and volumes during the first trimester of pregnancy can be used as predictors of subsequent adverse outcomes. METHODS: This was a prospective cohort study including women with singleton pregnancies between 10 and 13 weeks. 3D placental volume and vascular indices and uterine artery pulsatility index (UtA-PI) were measured. Adverse outcomes were defined whether there was any of the following complications: small for gestational age pregnancy, preterm delivery, and preeclampsia. The serum pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (ß-hCG) levels were also compared. We analyzed the screening performances of these parameters for prediction of any of adverse outcomes. RESULTS: Of 348 women screened, 300 women were completed follow-up. Overall, 57 (19.0%) of 300 women developed any of adverse pregnancy outcomes. Multiple logistic regression analysis demonstrated that gestational age-adjusted z-scores of log10 placental volume (odds ratio [OR], 0.572; 95% confidence interval [CI], 0.416-0.788), log10 placental vascularization flow index (VFI; OR, 0.676; 95% CI, 0.496-0.921), and log10 UtA-PI (OR, 1.910; 95% CI, 1.335-2.731) were significantly associated adverse pregnancy outcomes. The multivariate model combining placental VFI, placental volume, UtA-PI, and underweight or obese body mass index exhibited the highest screening performances (AUC = 0.77) and PAPP-A and ß-hCG did not add any significance to multivariate model. CONCLUSIONS: Placental volume and vascular indices at 10-13 weeks of gestation are significantly associated with adverse pregnancy outcomes. Combination of these placental indices and UtA-PI could improve the screening performance for adverse outcomes.

Assessment of potential infectivity of human norovirus in the traditional Korean salted clam product "Jogaejeotgal" by floating electrode-dielectric barrier discharge plasma.

This study investigated the antiviral effects of floating electrode-dielectric barrier discharge (FE-DBD) plasma treatment (1.1 kV, 43 kHz, N2 1.5 m/s, 5-30 min) against human norovirus (HuNoV) GII.4 in Jogaejeotgal Infectivity was assessed using real-time quantitative-PCR (RT-qPCR) following treatment of samples with propidium monoazide (PMA) and sodium lauroyl sarcosinate (Sarkosyl). This study also investigated the effects of FE-DBD plasma treatment on Jogaejeotgal quality (assessed using pH value and Hunter colors). Following inoculation, the average titers of HuNoV GII.4 in Jogaejeotgal significantly (P < 0.05) decreased with increases in the FE-DBD plasma treatment time in both the non-PMA-treated and PMA + Sarkosyl-treated samples; in the non-PMA and PMA + Sarkosyl treated Jogaejeotgal, HuNoV GII.4 titers (log10 copy number/µL) were to: 3.16 and 2.95 (5 min), 2.90 and 2.48 (10 min), 2.82 and 2.40 (15 min), 2.58 and 2.26 (20 min), 2.48 and 2.06 (25 min), and 2.23 and 1.91 (30 min), respectively. The average titers of HuNoV demonstrated significant (P < 0.05) reductions of 0.35 log10 (55.3%) in PMA + Sarkosyl-treated samples compared with the non-PMA treated samples following exposure to 5-30 min of FE-DBD plasma. Reductions of >1-log for HuNoV in PMA + Sarkosyl- treated Jogaejeotgal required treatments of FE-DBD of 5-30 min. Using the first order kinetic model (R2 = 0.95), GII.4 decimal reduction time (D-value) resulting from FE-DBD plasma was 23.75 min. The pH and Hunter colors ("L", "a", and "b") were not significantly different (P > 0.05) between the untreated and FE-DBD plasma-treated Jogaejeotgal. Based on these results, the PMA + Sarkosyl/RT-qPCR method could be assessing HuNoV viability following 5-30 min treatment of FE-DBD plasma. Furthermore, may be an optimal treatment for Jogaejeotgal without altering the food quality (color and pH).

Surveillance of the infection prevention and control practices of healthcare workers by an infection control surveillance-working group and a team of infection control coordinators during the COVID-19 pandemic.

BACKGROUND: During the ongoing coronavirus disease (COVID-19) pandemic, hospitals have strengthened their guidelines on infection prevention and control (IPC), and a rigorous adherence to these guidelines is crucial. An infection control surveillance-working group (ICS-WG) and infection control coordinators (ICCs) team were created to monitor the IPC practices of the healthcare workers (HCWs) in a regional hospital in Korea. This study analyzed the surveillance results and aimed to identify what IPC practices needed improvement. METHODS: During phase 1 (March to April 2020), the ICS-WG performed random audits, recorded incidences of improper IPC practices, and provided advice to the violators. During phase 2 (April to July), the ICCs inspected the hospital units and proposed practical ideas about IPC. The surveillance and proposals targeted the following practices: patient screening, usage of personal protective equipment (PPE), hand and respiratory hygiene, equipment reprocessing, environmental cleaning, management of medical waste, and social distancing. RESULTS: In phase 1, of the 127 violations observed, most (32.3%) corresponded to hand and respiratory hygiene. In phase 2, the highest proportion of violation per category was observed in the management of medical waste (37.8%); among these, a higher proportion of violation (71.4%) was observed in the collection of medical waste. Of the 106 proposals made by the ICCs, the most addressed practice was patient screening (28.3%). No case of nosocomial infection was reported during the study period. CONCLUSION: Adherence to proper hand and respiratory hygiene was inadequate at the early stage of the COVID-19 pandemic. The results indicate that more attention and further training are needed for the management of medical waste, particularly medical waste collection, and that continuous upgrading of the strategies for patient screening is essential. These results will be useful in helping other healthcare facilities to establish their IPC strategies.

Risk factors for intraoperative hemorrhage during cesarean myomectomy.

OBJECTIVE: We intended to identify the risk factors of intraoperative hemorrhage on occasions of a combined operation of myomectomy with cesarean section for patients with uterine leiomyoma. MATERIALS AND METHODS: A retrospective cohort study was done of all patients who underwent cesarean myomectomy for intramural leiomyoma at a single university hospital. Cases identified with subserosal leiomyoma, placental disorder, and comorbid conditions related to coagulopathy were excluded. All the included cases were classified into intraoperative hemorrhage and non-hemorrhage group. Obstetric and demographic factors and parameters of leiomyoma were compared between two groups. RESULTS: A total of 302 women underwent cesarean myomectomy during the study period. Among these women, 212 pregnant women met the inclusion criteria. Intraoperative hemorrhage occurred in 43 women (20.3%). There was no significant intergroup difference in the number of removed leiomyomas. Multiple logistic regression analysis demonstrated that lower segmental location (odds ratio [OR], 2.827; 95% confidence interval [CI], 1.033-7.734, P = 0.043) and the diameter (OR, 1.167; 95% CI, 1.044-1.305, P = 0.006) were significant independent risk factors for hemorrhage during cesarean myomectomy. The combination of ≥ 8 cm diameter or lower segmental position of the leiomyoma yielded a specificity of 79.3% for operative hemorrhage during cesarean myomectomy. The negative predictive value of this combination was 88.7% for operative hemorrhage with a prevalence of 20%. CONCLUSION: The large size and lower segmental position of the leiomyoma are significantly risk factors for intraoperative hemorrhage during cesarean myomectomy. If the leiomyoma is located in the uterine fundus or body and its diameter is less than 8 cm, the removal of leiomyoma may be considered at the time of cesarean section.

Clinical Practice Guidelines for Prenatal Aneuploidy Screening and Diagnostic Testing from Korean Society of Maternal-Fetal Medicine: (2) Invasive Diagnostic Testing for Fetal Chromosomal Abnormalities.

The Korean Society of Maternal Fetal Medicine proposed the first Korean guideline on prenatal aneuploidy screening and diagnostic testing, in April 2019. The clinical practice guideline (CPG) was developed for Korean women using an adaptation process based on good-quality practice guidelines, previously developed in other countries, on prenatal screening and invasive diagnostic testing for fetal chromosome abnormalities. We reviewed current guidelines and developed a Korean CPG on invasive diagnostic testing for fetal chromosome abnormalities according to the adaptation process. Recommendations for selected 11 key questions are: 1) Considering the increased risk of fetal loss in invasive prenatal diagnostic testing for fetal genetic disorders, it is not recommended for all pregnant women aged over 35 years. 2) Because early amniocentesis performed before 14 weeks of pregnancy increases the risk of fetal loss and malformation, chorionic villus sampling (CVS) is recommended for pregnant women who will undergo invasive prenatal diagnostic testing for fetal genetic disorders in the first trimester of pregnancy. However, CVS before 9 weeks of pregnancy also increases the risk of fetal loss and deformity. Thus, CVS is recommended after 9 weeks of pregnancy. 3) Amniocentesis is recommended to distinguish true fetal mosaicism from confined placental mosaicism. 4) Anti-immunoglobulin should be administered within 72 hours after the invasive diagnostic testing. 5) Since there is a high risk of vertical transmission, an invasive prenatal diagnostic testing is recommended according to the clinician's discretion with consideration of the condition of the pregnant woman. 6) The use of antibiotics is not recommended before or after an invasive diagnostic testing. 7) The chromosomal microarray test as an alternative to the conventional cytogenetic test is not recommended for all pregnant women who will undergo an invasive diagnostic testing. 8) Amniocentesis before 14 weeks of gestation is not recommended because it increases the risk of fetal loss and malformation. 9) CVS before 9 weeks of gestation is not recommended because it increases the risk of fetal loss and malformation. 10) Although the risk of fetal loss associated with invasive prenatal diagnostic testing (amniocentesis and CVS) may vary based on the proficiency of the operator, the risk of fetal loss due to invasive prenatal diagnostic testing is higher in twin pregnancies than in singleton pregnancies. 11) When a monochorionic twin is identified in early pregnancy and the growth and structure of both fetuses are consistent, an invasive prenatal diagnostic testing can be performed on one fetus alone. However, an invasive prenatal diagnostic testing is recommended for each fetus in cases of pregnancy conceived via in vitro fertilization, or in cases in which the growth of both fetuses differs, or in those in which at least one fetus has a structural abnormality. The guidelines were established and approved by the Korean Academy of Medical Sciences. This guideline is revised and presented every 5 years.

Clinical Practice Guidelines for Prenatal Aneuploidy Screening and Diagnostic Testing from Korean Society of Maternal-Fetal Medicine: (1) Prenatal Aneuploidy Screening.

In 2019, the Korean Society of Maternal-Fetal Medicine developed the first Korean clinical practice guidelines for prenatal aneuploidy screening and diagnostic testing. These guidelines were developed by adapting established clinical practice guidelines in other countries that were searched systematically, and the guidelines aim to assist in decision making of healthcare providers providing prenatal care and to be used as a source for education and communication with pregnant women in Korea. This article delineates clinical practice guidelines specifically for maternal serum screening for fetal aneuploidy and cell-free DNA (cfDNA) screening. A total of 19 key questions (12 for maternal serum and 7 for cfDNA screening) were defined. The main recommendations are: 1) Pregnant women should be informed of common fetal aneuploidy that can be detected, risks for chromosomal abnormality according to the maternal age, detection rate and false positive rate for common fetal aneuploidy with each screening test, limitations, as well as the benefits and risks of invasive diagnostic testing, 2) It is ideal to give counseling about prenatal aneuploidy screening and diagnostic testing at the first prenatal visit, and counseling is recommended to be given early in pregnancy, 3) All pregnant women should be informed about maternal serum screening regardless of their age, 4) cfDNA screening can be used for the screening of trisomy 21, 18, 13 and sex-chromosome aneuploidy. It is not recommended for the screening of microdeletion, 5) The optimal timing of cfDNA screening is 10 weeks of gestation and beyond, and 6) cfDNA screening is not recommended for women with multiple gestations. The guideline was reviewed and approved by the Korean Academy of Medical Sciences.

Virucidal Effects of Dielectric Barrier Discharge Plasma on Human Norovirus Infectivity in Fresh Oysters (Crassostrea gigas).

This study investigates the effects of dielectric barrier discharge (DBD) plasma treatment (1.1 kV, 43 kHz, N2 1.5 L/min, 10~60 min) on human norovirus (HuNoV) GII.4 infectivity in fresh oysters. HuNoV viability in oysters was assessed by using propidium monoazide (PMA) as a nucleic acid intercalating dye before performing a real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Additionally, the impact of the DBD plasma treatment on pH and Hunter colors was assessed. When DBD plasma was treated for 60 min, the HuNoV genomic titer reduction without PMA pretreatment was negligible (<1 log copy number/µL), whereas when PMA treatment was used, HuNoV titer was reduced to >1 log copy number/µL in just 30 min. D1 and D2-value of HuNoV infectivity were calculated as 36.5 and 73.0 min of the DBD plasma treatment, respectively, using the first-order kinetics model (R2 = 0.98). The pH and Hunter colors were not significantly different (p > 0.05) between the untreated and DBD-plasma-treated oysters. The results suggest that PMA/RT-qPCR could help distinguish HuNoV infectivity without negatively affecting oyster quality following >30 min treatment with DBD plasma. Moreover, the inactivation kinetics of nonthermal DBD plasma against HuNoV in fresh oysters might provide basic information for oyster processing and distribution.

Level of contamination in the feces of several species at major inland pollution sources in the drainage basin of Yeoja Bay, Republic of Korea.

We assessed the levels of fecal contamination and the originating species of 12 major inland pollutants in the drainage basin of Yeoja Bay. The presence of the human-specific (HF183), ruminant-specific (BacR and Rum-2-Bac), pig-specific (Pig-Bac-2 and Pig-2-Bac), avian-specific (GFD), and gull-specific (Gull2) markers in water samples (n = 34) from 12 inland pollution sources around Yeoja Bay was analyzed. HF183 was detected in 97% of the water samples, and all major inland pollution sources were contaminated with human feces. BacR and Rum-2-Bac were detected in 94% and 11%, respectively, of the water samples. Pig-2-Bac was not detected in the inland pollution sources, but site L5 might be contaminated with swine feces. Gull2 was not detected, whereas GFD was detected in 26% of the water samples. This study highlights the utility of a MST toolbox approach for characterizing the water quality of inland pollution sources and identifying the feces producing species.

Abundance, antimicrobial resistance, and virulence of pathogenic Vibrio strains from molluscan shellfish farms along the Korean coast.

To reduce the outbreaks caused by the major pathogenic Vibrio species, V. parahaemolyticus, V. vulnificus, and V. cholerae, the distribution, antibiotic resistance, and virulence of these Vibrio strains were monitored in shellfish and seawater along the Korean coast. Among the Vibrio strains, V. parahaemolyticus was the most abundant species; during summer, this strain showed a substantial increase that correlated with the water temperature. Although >99.0% of the Vibrio species isolates were sensitive to seven antimicrobials recommended by the Center for Disease Control and Prevention for the treatment of Vibrio infections, multiple-antibiotic resistance to at least three antimicrobials was found in 14.3% to 50.0% of each Vibrio species. Among V. parahaemolyticus isolates, 14.3% were positive for the trh gene, whereas only 1% was positive for the tdh gene. These results should aid in implementing proper precautions to avoid potential human health risks associated with exposure to pathogenic Vibrio species.