Intrahospital transmission and infection control of Candida auris originating from a severely infected COVID-19 patient transferred abroad.

BACKGROUND: Intrahospital spread of Candida auris, which survives tenaciously in many environments, can cause sustained colonization and infection. A large outbreak of C. auris was experienced in the intensive care units (ICUs) at the study hospital during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: The index patient with severe COVID-19, who was transferred from Vietnam in January 2022, developed C. auris candidaemia 10 days after hospitalization. From mid-June 2022 to January 2023, strengthened infection prevention and control (IPC) measures were implemented in three ICUs: (1) contact precautions and isolation (CPI) for C. auris-positive cases; (2) surveillance cultures including point-prevalence (N=718) for patients or close contacts or ICU-resident healthcare workers (HCWs); (3) intensive environmental disinfection with 10-fold diluted bleach; and (4) 2% chlorhexidine bathing for all ICU patients. Environmental cultures (ECx) on surfaces and shared objects (N=276) were conducted until early September 2022, when all ECx were negative. RESULTS: Among 53 C. auris-positive patients between February 2022 and January 2023, invasive infections resulted in seven cases of candidaemia and one case of pneumonia. C. auris was isolated from reusable tympanic thermometers (TTMs) contaminated with earwax. The isolation rate of C. auris in ECx decreased from 6.8% in June 2022 to 2.0% in August 2022, and was no longer detected in TTMs. Colonization in HCWs was remarkably rare (0.5%). The number of C. auris-positive patients peaked in July (N=10) then decreased gradually. By January 2023, no C. auris were isolated in the ICU. CONCLUSION: Aggressive IPC measures with CPI, ECx and surveillance, decontamination of TTMs, and bathing were effective in successfully controlling this C. auris outbreak.

Mental health states and influencing factors of risky and problem drinking in South Korean female adolescents.

OBJECTIVES: Alcohol is one of the most used and abused psychoactive substances by adolescents. We investigated influencing factors of risky and problem drinking in Korean female adolescents. STUDY DESIGN: The study design used is a cross-sectional modeling. METHODS: We used data from the 13th Korean Youth Risk Behavior Web-based Survey (KYRBS) conducted in 2017. KYRBS data were obtained from a stratified, multistage, clustered sample. Risky drinking was binge drinking and problem drinking was drinking with several conflicts association with alcohol consumption. RESULTS: Among 62,276 participants, the rates of current, risky, and problem drinking among all participants were 16.1%, 8.3%, and 6.1%, respectively. Although all of these rates were higher in males, risky and problem drinking rates among current female drinkers were higher than those of males (55.4 vs 48.5%, 38.9 vs 37.2%, respectively). Problem drinking was most strongly associated with risky drinking (adjusted odds ratio: 17.53 [95% confidence interval: 14.63-21.00]), similarly, risky drinking was most strongly associated with problem drinking in female current drinkers (17.76 [14.84-21.27]). Current smoking was the second strongest risk factor for risky and problem drinking in females (5.22 [3.92-6.95] and 2.93 [2.21-3.89], respectively). CONCLUSION: Many female adolescents in Korea drink alcohol in an unhealthy manner. The female risky and problem drinking rates among current drinkers were higher than those of males. Risky drinking and problem drinking was most significant influencing factor among females, reciprocally. Public education on abstinence in female adolescents is warranted.

Prostate cancer detection rate according to lesion visibility using ultrasound and MRI.

AIM: To evaluate the difference in prostate cancer detection rates according to lesion visibility using transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) before biopsy. MATERIALS AND METHODS: Patients who underwent TRUS-guided prostate biopsy in 2016 and 2017 (n=1,022) were divided into three groups: (1) patients who did not undergo a prebiopsy MRI (group 1, n=622); (2) patients without visible lesions on the prebiopsy MRI (group 2, n=77); and (3) patients with visible lesions on the prebiopsy MRI (group 3, n=323). Biopsy results were compared using chi-square tests or independent t-tests between patients with and without TRUS-visible lesions in each group. A logistic regression test was used to determine the variables independently associated with the detection of clinically significant cancer. RESULTS: Focal lesions were visible on TRUS in 710 patients. Clinically significant cancers were detected in 39.4% and 13.1% of patients with and without TRUS-visible lesions, respectively (p<0.001). The cancer detection rate was significantly higher in patients with TRUS-visible lesions in groups 1 and 3 (p<0.001). Within group 1, the Gleason scores, number of positive cores, and the cancer involvement ratios were significantly greater in patients with TRUS-visible lesions than in patients without TRUS-visible lesions. MRI- and TRUS visibility were positively associated with the detection of clinically significant prostate cancer (p=0.002 and p<0.001, respectively). CONCLUSION: TRUS- and MRI-visible focal lesions in the prostate were significantly associated with the detection of clinically significant cancer.

Prebiopsy biparametric MRI: differences of PI-RADS version 2 in patients with different PSA levels.

AIM: To validate the diagnostic accuracy of Prostate Imaging-Reporting and Data System (PI-RADS) version 2 in detecting clinically significant prostate cancer (csPCa, Gleason score ≥7) on prebiopsy biparametric MRI (bpMRI) in patients with different prostate-specific antigen (PSA) levels. MATERIALS AND METHODS: This retrospective study included 184 patients who underwent prebiopsy bpMRI followed by transrectal ultrasonography-guided biopsy between June 2015 and February 2017. Reader 1 performed a combination of systematic and targeted biopsy with cognitive fusion after reviewing bpMRI and reader 2 reviewed the bpMRIs retrospectively. PI-RADS categories 4 and 5 were considered positive, and the results of the biopsy were considered the reference standard. Diagnostic performance of PI-RADS of bpMRI was evaluated in two PSA groups with a PSA cut-off level of 10 ng/ml and compared to PSA and the PSA density using receiver operating characteristics (ROC) curve analysis. RESULTS: csPCa was diagnosed in 24 of 123 patients (19.5%) and 26 of 61 patients (42.6%) in the low and high PSA groups, respectively. A PI-RADS v2 category by either readers 1 or 2 had a significantly better performance to detect csPCa than PSA in both PSA groups. In the high PSA group, only one csPCa was missed by reader 2, but none by reader 1. In the low PSA group, readers 1 and 2 were unable to detect seven and five of the 24 csPCas, respectively. CONCLUSION: Prebiopsy bpMRI has good performance for detecting csPCa in the high PSA group but may miss small-volume csPCa in the low PSA group.

Dynamic contrast-enhanced MR imaging of the rectum: Correlations between single-section and whole-tumor histogram analyses.

PURPOSE: To evaluate the interobserver and intermethod correlations of histogram metrics of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters acquired by multiple readers using the single-section and whole-tumor volume methods. MATERIALS AND METHODS: Four DCE parameters (Ktrans, Kep, Ve , Vp) were evaluated in 45 patients (31 men and 14 women; mean age, 61±11 years [range, 29-83 years]) with locally advanced rectal cancer using pre-chemoradiotherapy (CRT) MRI. Ten histogram metrics were extracted using two methods of lesion selection performed by three radiologists: the whole-tumor volume method for the whole tumor on axial section-by-section images and the single-section method for the entire area of the tumor on one axial image. The interobserver and intermethod correlations were evaluated using the intraclass correlation coefficients (ICCs). RESULTS: The ICCs showed excellent interobserver and intermethod correlations in most of histogram metrics of the DCE parameters. The ICCs among the three readers were > 0.7 (P<0.001) for all histogram metrics, except for the minimum and maximum. The intermethod correlations for most of the histogram metrics were excellent for each radiologist, regardless of the differences in the radiologists' experience. CONCLUSION: The interobserver and intermethod correlations for most of the histogram metrics of the DCE parameters are excellent in rectal cancer. Therefore, the single-section method may be a potential alternative to the whole-tumor volume method using pre-CRT MRI, despite the fact that the high agreement between the two methods cannot be extrapolated to post-CRT MRI.

Evaluation of treatment pattern and symptom control in patients with gastroesophageal reflux disease: multihospital questionnaire survey on the current situation in Korea.

Proton pump inhibitors (PPIs) are the most effective treatment for gastroesophageal reflux disease (GERD); however, a considerable number of patients fail to respond to PPI therapy and complain of nocturnal heartburn and sleep disturbance. The aims of this study are to evaluate the treatment pattern of GERD-related medications and their efficacy in relieving nocturnal heartburn. A total of 334 patients with GERD receiving PPI therapy within 6 months were enrolled in a multihospital questionnaire survey from January, 2014 to March, 2015. GERD symptoms and patients' satisfaction were assessed by patient questionnaires, and treatment patterns of GERD-related medications were assessed by investigators. Among the 334 patients, 95.8% used PPI once daily and 58.6% used a half-dose of PPI. The PPI treatment pattern was changed in 26.6% of all patients, of those, 54% of the patients doubled the PPI dose, and 29.2% of the patients switched to another PPI. Approximately 60.3% of all patients were prescribed more than three GERD-related medications. The overall satisfaction rate was 61.8%, and 32.2% of patients experienced nocturnal heartburn and sleep disturbance. In the extended-release PPI group, there were fewer nocturnal symptoms compared with the conventional PPI group (10% vs. 33.7%, respectively, P = 0.027). The use of more than three medications was inversely associated with patients' satisfaction (OR = 0.355, 95% CI; 0.197-0.642, P = 0.001). Most patients were prescribed adjunctive medications other than PPIs; however, patients' satisfaction was inversely associated with multiple drugs. Patients' satisfaction was superior in extended-release PPIs than conventional PPIs for the relief of nocturnal heartburn in Korean patients.

Clinical impact of tumor volume reduction in rectal cancer following preoperative chemoradiation.

PURPOSE: The purpose of this study was to correlate tumor volumetric analysis obtained using magnetic resonance (MR) imaging with disease-free survival in patients with advanced rectal cancer who underwent preoperative chemoradiotherapy (CRT). PATIENTS AND METHODS: Institutional review board approval was obtained and patient informed consent was waived. This study included 74 patients (47 men, 27 women; mean age, 64 years±10 [SD] years) who underwent preoperative CRT and subsequent rectal surgery between January 2007 and December 2010. Two radiologists who were blinded to the clinical outcome measured tumor volume separately on two sets of MR images obtained before and after CRT. Patients were classified into two groups according to the episode of recurrence and recorded disease-free survival. To assess factors relevant to disease-free survival, univariate and multivariate Cox regression analysis were performed for tumor volume reduction ratio, circumferential resection margin, tumor regression grade, and pathologic staging. RESULTS: Tumor volume reduction ratio (P=0.009), circumferential resection margin (P=0.008) and tumor regression grade (P=0.002) were significantly associated with disease-free survival. At multivariate analysis, tumor volume reduction ratio was the single variable that was associated with disease-free survival (P=0.003). Tumor volume reduction ratio was also a reliable parameter with an excellent interobserver correlation between two readers for pre-CRT volume (ICC=0.939; 95%CI: 0.885-0.979; P<0.001) and post-CRT volume (ICC=0.889; 95%CI: 0.845-0.934; P<0.001). CONCLUSIONS: MR volumetric measurement of rectal cancer helps predict disease-free survival in patients with rectal cancer who underwent preoperative CRT.

Short communication: Epidemiological assessment of Strongyloides stercoralis in Fijian children.

As a part of the lymphatic filariasis (LF) transmission assessment survey (TAS)/soil-transmitted helminths (STH) prevalence survey in Western Division of Fiji, a pilot screen for Strongyloides stercoralis (SS) in school children was undertaken using a combination of the Baermann concentration (BC) method and real-time PCR assays. Using BC, faecal samples collected from 111 children of 7 schools were examined. A single child was positive for larvae of SS and underwent a clinical examination finding an asymptomatic infection. Other members of this child's household were screened with BC, finding none infected. Aliquots of 173 faecal samples preserved in ethanol originating from all schools were examined by real-time PCR, and the prevalence of SS infection was 3.5%. Our study confirms the existence of SS infection on Fiji and showed that assessing SS prevalence alongside TAS/STH survey is a convenient access platform, allowing introduction of other surveillance techniques such as BC and real-time PCR.

Estimation of pork quality traits using exsanguination blood and postmortem muscle metabolites.

The current study was designed to estimate the pork quality traits using metabolites from exsanguination blood and postmortem muscle simultaneously under the Korean standard pre- and post-slaughter conditions. A total of 111 Yorkshire (pure breed and castrated male) pigs were evaluated under the Korean standard conditions. Measurements were taken of the levels of blood glucose and lactate at exsanguination, and muscle glycogen and lactate content at 45 min and 24 h postmortem. Certain pork quality traits were also evaluated. Correlation analysis and multiple regression analysis including stepwise regression were performed. Exsanguination blood glucose and lactate levels were positively correlated with each other, negatively related to postmortem muscle glycogen content and positively associated with postmortem muscle lactate content. A rapid and extended postmortem glycolysis was associated with high levels of blood glucose and lactate, with high muscle lactate content, and with low muscle glycogen content during postmortem. In addition, these were also correlated with paler meat color and reduced water holding capacity. The results of multiple regression analyses also showed that metabolites in exsanguination blood and postmortem muscle explained variations in pork quality traits. Especially, levels of blood glucose and lactate and content of muscle glycogen at early postmortem were significantly associated with an elevated early glycolytic rate. Furthermore, muscle lactate content at 24 h postmortem alone accounted for a considerable portion of the variation in pork quality traits. Based on these results, the current study confirmed that the main factor influencing pork quality traits is the ultimate lactate content in muscle via postmortem glycolysis, and that levels of blood glucose and lactate at exsanguination and contents of muscle glycogen and lactate at postmortem can explain a large portion of the variation in pork quality even under the standard slaughter conditions.

Staphylococcal enterotoxin sensitization in a community-based population: a potential role in adult-onset asthma.

BACKGROUND: Recent studies suggest that Staphylococcus aureus enterotoxin sensitization is a risk factor for asthma. However, there is a paucity of epidemiologic evidence on adult-onset asthma in community-based populations. OBJECTIVE: We sought to evaluate the epidemiology and the clinical significance of staphylococcal enterotoxin sensitization in community-based adult populations. METHODS: The present analyses were performed using the baseline data set of Korean adult population surveys, consisting of 1080 adults (mean age = 60.2 years) recruited from an urban and a rural community. Questionnaires, methacholine challenge tests, and allergen skin tests were performed for defining clinical phenotypes. Sera were analysed for total IgE and enterotoxin-specific IgE using ImmunoCAP. RESULTS: Staphylococcal enterotoxin sensitization (≥ 0.35 kU/L) had a prevalence of 27.0%. Risk factors were identified as male sex, current smoking, advanced age (≥ 61 years), and inhalant allergen sensitization. Current asthma was mostly adult onset (≥ 18 years old) and showed independent associations with high enterotoxin-specific IgE levels in multivariate logistic regression tests. In multivariate linear regressions, staphylococcal enterotoxin-specific IgE level was identified as the major determinant factor for total IgE level. CONCLUSIONS AND CLINICAL RELEVANCE: Staphylococcal enterotoxin sensitization was independently associated with adult-onset asthma in adult community populations. Strong correlations between the enterotoxin-specific IgE and total IgE levels support the clinical significance. The present findings warrant further studies for the precise roles of staphylococcal enterotoxin sensitization in the asthma pathogenesis.

Preferential location for arterial dissection presenting as golf-related stroke.

SUMMARY: Golf-related stroke has not been systematically reviewed. The purpose of our study was to describe in detail this particular stroke syndrome. Seven patients were analyzed at a university hospital and 7 patients were reviewed from MEDLINE literature. General demographics, symptom onset, neurologic signs, radiologic findings, and outcome were investigated. A total of 14 patients including 7 patients from the MEDLINE search were analyzed; all were men, with a mean age of 46.9 ± 12.8 years. Symptom onset was classified as during the golf swing (n = 9), unknown (n = 3), and after playing golf (n = 2). Most patients (n = 12) showed involvement of the vertebral artery and 2 patients showed involvement of the internal carotid artery (P = .008). Nine dissections were found on the right side, 3 on the left side, and 2 were bilateral (P = .046). Twelve patients had extracranial involvement and 2 patients had intracranial involvement (P = .008). Seven patients returned to normal, 5 returned to independence, 1 had unknown status, and 1 died. The anatomic preference of golf-related craniocervical arterial dissection is associated with the extracranial and vertebrobasilar system with a right-sided tendency as the result of stereotypical rotational movement during a golf swing.

Differences in the risk factors of reflux esophagitis according to age in Korea.

The prevalence of gastroesophageal reflux disease in Korea has been believed to be low, but the incidence of gastroesophageal reflux disease in Korea is expected to increase because of the longer life expectancy and more ingestion of westernized food. The aim of this study was to report differences in the risk factors of reflux esophagitis (RE) according to age in Korea. We prospectively recruited the subjects who had RE among those who visited a health promotion center for upper gastrointestinal cancer surveillance at Hallym Medical Center (five institutions) between January 2008 and February 2009. The enrolled study participants comprised 742 subjects with RE and 1484 healthy controls. The independent risk factors of RE in young and adult group were male sex, smoking, coffee, body mass index ≥ 25, hiatal hernia, and Helicobacter pylori negativity. The risk factors of RE in elderly group were smoking, coffee, and hiatal hernia. The risk factors for RE according to age group were found to differ. In elderly group, Helicobacter pylori infection was not a significant protective factor contrary to young and adult groups.

Evaluation of endogenous metabolic markers of hepatic CYP3A activity using metabolic profiling and midazolam clearance.

This study aimed to evaluate endogenous metabolic markers of hepatic cytochrome P450 (CYP)3A activity in healthy subjects using a metabolomics approach. Twenty-four subjects received the following medication during the following three study periods: 1 mg of i.v. midazolam alone (control phase), 1 mg of i.v. midazolam after 4 days of pretreatment with 400 mg of ketoconazole once daily (CYP3A-inhibited phase), and 2.5 mg of i.v. midazolam after 10 days of pretreatment with 600 mg of rifampicin once daily (CYP3A-induced phase). During each study period, 24 h before and after the administration of midazolam, urine samples were collected at 12-h intervals for metabolomic analyses. We derived an equation to predict midazolam clearance (CL) based on several of these markers. We demonstrated that a combination of the concentrations and ratios of several endogenous metabolites and the CYP3A5*3 genotype is a reliable predictive marker of hepatic CYP3A activity as assessed by i.v. administration of midazolam.

Characteristic features of ageing in Korean women's hair and scalp.

BACKGROUND: The effect of age on hair properties has previously been investigated in white and Japanese women; however, little is known of the age-related characteristic features of hair in Korean women. OBJECTIVES: To determine the ageing features of Korean women's hair by examining physical and biological factors in sufficient numbers of participants. METHODS: In total, 150 healthy Korean women (aged 23-69 years) living in Seoul were allocated to five age-graded groups. Age-related changes of various features of the scalp and hair shaft were measured, including hair density, diameter, tensile strength and lustre, and grey-hair ratio. The hair-shaft compositions of minerals, amino acids and steroid hormones were analysed by high-performance liquid chromatography. RESULTS: Hair-loss parameters (hair density, diameter and tensile strength) and hair lustre decreased significantly with age, beginning in the subjects' 40s. The hair-whiteness value increased significantly with age, beginning in their 60s, due to an increase in the ratio of grey hair. Calcium and magnesium levels greatly exceeded the reference ranges and declined in an age-dependent manner, while potassium and phosphorus levels increased with age. No age-related change of hair-shaft amino acid content was evident. The contents of sterols and their metabolites (cholesterol, desmosterol, lanosterol and pregnenolone) increased significantly with age, but there was no correlation between the examined sex steroids and age. CONCLUSIONS: These results show that intrinsic ageing produces diverse changes in the hair and scalp features of Korean women from their 40s, and the ageing features of Korean women's hair could be partially different from that of women in other countries.

Serine palmitoyltransferase inhibitor myriocin induces growth inhibition of B16F10 melanoma cells through G(2) /M phase arrest.

OBJECTIVES: Melanoma is the most aggressive form of skin cancer, and it resists chemotherapy. Candidate drugs for effective anti-cancer treatment have been sought from natural resources. Here, we have investigated anti-proliferative activity of myriocin, serine palmitoyltransferase inhibitor, in the de novo sphingolipid pathway, and its mechanism in B16F10 melanoma cells. MATERIAL AND METHODS: We assessed cell population growth by measuring cell numbers, DNA synthesis, cell cycle progression, and expression of cell cycle regulatory proteins. Ceramide, sphingomyelin, sphingosine and sphingosine-1-phosphate levels were analysed by HPLC. RESULTS: Myriocin inhibited proliferation of melanoma cells and induced cell cycle arrest in the G(2) /M phase. Expressions of cdc25C, cyclin B1 and cdc2 were decreased in the cells after exposure to myriocin, while expression of p53 and p21(waf1/cip1) was increased. Levels of ceramide, sphingomyelin, sphingosine and sphingosine-1-phosphate in myriocin-treated cells after 24 h were reduced by approximately 86%, 57%, 75% and 38%, respectively, compared to levels in control cells. CONCLUSIONS: Our results suggest that inhibition of sphingolipid synthesis by myriocin in melanoma cells may inhibit expression of cdc25C or activate expression of p53 and p21(waf1/cip1) , followed by inhibition of cyclin B1 and cdc2, resulting in G(2) /M arrest of the cell cycle and cell population growth inhibition. Thus, modulation of sphingolipid metabolism by myriocin may be a potential target of mechanism-based therapy for this type of skin cancer.

Clonorchis sinensis infection is positively associated with atopy in endemic area.

BACKGROUND: Epidemiologic studies have suggested that helminth infections play a protective role against allergy; this inverse association, however, has not been consistent. Clonorchis sinensis, the liver fluke of human, is prevalent in the Far East. The association between C. sinensis infection and allergy has not yet been reported. OBJECTIVE: We evaluated the association between clonorchiasis and atopy or allergic diseases in adults in endemic areas of clonorchiasis. METHODS: A total of 1116 subjects (males 419, females 697; age range, 30-86; mean age=61 years) were recruited from two endemic areas of C. sinensis in Korea. Clonorchiasis was confirmed by stool examination. Allergic symptoms were evaluated with a modified ISAAC questionnaire, and atopy was defined by skin prick test for common inhalant allergens. Total serum IgE and C. sinensis-specific IgE level was measured by ELISA and methacholine bronchial provocation test was performed to evaluate airway hyperresponsiveness (AHR). RESULTS: Clonorchiasis was positively associated with atopy [odds ratio (OR), 1.856; 95% confidence interval (CI), 1.199-2.873] and high levels of total serum IgE (OR, 1.455; 95% CI, 1.050-2.016). Higher association with clonorchiasis was shown in subjects who showed both atopy and high total serum IgE levels (OR, 2.540; 95% CI, 1.448-4.455). Clonorchiasis had no association with wheezing, AHR, asthma or allergic rhinitis. CONCLUSION AND CLINICAL RELEVANCE: Clonorchiasis was positively associated with atopy in adults in endemic area.

Fitz-Hugh-Curtis Syndrome: single centre experiences.

This study was conducted to report 10 cases of Fitz-Hugh-Curtis Syndrome (FHCS) diagnosed with CT and 101 cases of FHCS-like lesion that suggested perihepatitis during laparoscopic surgery. We reviewed retrospectively the images of 3,674 laparoscopies for obstetrical and gynaecological diseases and analysed 10 cases of FHCS diagnosed by clinical patterns and CT. All the 10 cases showed liver capsular enhancement on CT. Among the 3,674 laparoscopies, we found 101 cases (2.7%) with FHCS like lesion. Among them, 23 cases were during laparoscopic procedure for endometriosis, 16 for gynaecological malignant tumours, 16 for benign adnexal diseases excluding endometriosis, 13 for uterine leiomyoma, 7 for pelvic inflammatory disease, 2 had peritoneal tuberculosis and 21 for other gynaecological diseases. Further consideration should be given for the causes of FHCS other than N. gonorrhoeae and C. trachomatis. Because FHCS may represent various clinical phases, other considerations and clinical classifications are necessary for treatment.

Detection of Clonorchis sinensis in stool samples using real-time PCR.

Human clonorchiasis, caused by infection with the trematode Clonorchis sinensis, is a common health problem in East Asia. In an attempt to develop a new, sensitive method for the diagnosis of the disease, the use of a real-time PCR (targeting the internal-transcribed-spacer-2 sequence of the parasite) to detect C. sinensis-specific DNA in faecal samples has recently been evaluated. The PCR-based assay, which included an internal control to detect any inhibition of the amplification by faecal constituents in the sample, was performed on stool samples and on DNA controls representing a wide range of intestinal microorganisms. The assay appeared very specific, only showing positivity with C. sinensis and Opisthorchis felineus. The sensitivity of the assay was explored by testing 170 preselected samples of human faeces, from an endemic area of South Korea, which had known (microscopically-determined) densities of C. sinensis eggs. The sensitivity of the assay was 100% for the 74 samples that each had > 100 eggs/g and 91.4% for the other 70 samples found egg-positive by microcopy (i.e. those that had

Mechanotransduction pathways of low-intensity ultrasound in C-28/I2 human chondrocyte cell line.

Low-intensity ultrasound (LIUS) has recently been considered to be an effective method to induce cartilage repair and/or regeneration after injury. Nevertheless, there is no study to provide a cellular mechanism or signal pathways of LIUS stimulation. The current study is designed to investigate the effects of LIUS on the mechanotransduction pathways in C-28/I2, an immortalized human chondrocyte cell line. C-28/I2 cells were treated with LIUS at an intensity of 200 mW/cm2 using Noblelife from Duplogen. The role of stretch-activated channels (SAC) and integrins that are most well-known mechanoreceptors on the chondrocyte cell surface was first examined in mediating the LIUS effects on the expression of type II collagen and aggrecan. When analysed by reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry, gadolinium (a specific inhibitor of SACs) or GRGDSP (a peptide inhibitor of integrins) specifically reduced the LIUS-induced elevation of type II collagen and aggrecan expressions depending on the incubation time. In addition, the LIUS treatment of C-28/I2 cells induced the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) but not p38 kinase among the members of the mitogen-activated protein kinases (MAPKs). The phosphorylation of ERK by LIUS was repressed by a specific inhibitor of the ERK pathway and integrin function. These results suggest that the LIUS signal might be mediated via canonical mechanoreceptors of SACs and integrins and subsequently through JNK and ERK pathways. The present study provides the first evidence for the activation of the mechanotransduction pathways by LIUS in human chondrocytes.

Establishment of a basic method for manipulating preantral follicles: effects of retrieval method on in vitro growth of preantral follicles and intrafollicular oocytes.

The aim of this study was to establish a basic manipulation protocol of preantral follicles for deriving developmentally competent oocytes. Primary, early and late secondary follicles retrieved from the ovaries of 14-day-old F1 (C57BL/6 x DBA2) female mice mechanically or enzymatically were cultured singly and in vitro growth of the follicles and maturation of intrafollicular oocytes were subsequently monitored. A mechanical method retrieved more (p < 0.0001) follicles (339 +/- 48 vs. 202 +/- 28) than an enzymatic method. However, the enzymatic method collected more singly isolated follicles that could be provided for subsequent culture (102 +/- 26 vs. 202 +/- 28). When an enzymatic method was employed, early and late secondary follicles required 9 and 6 days for reaching the maximal incidence of the pseudoantral stage. However, primary follicles were not possible to develop into the pseudoantral stage. The optimal duration of oocyte maturation from the onset of follicle culture was 7 days and 5-7 days for early and late secondary follicles, respectively. A general decrease in oocyte diameter (65.2-65.53 microm vs. 75 microm) and zona thickness (5.41-5.74 microm vs. 7.76 microm) was detected in in vitro-derived compared with in vivo-derived matured oocytes. Pronuclear formation was detected in 86-94% of mature oocytes after parthenogenetic activation and no significant difference was detected among groups. These results showed that preantral follicles retrieved by an enzymatic method underwent step-by-step growth in vitro, which could yield mature oocytes.