Establishment of a useful in vitro decidual induction model using eCG-primed nonpregnant mouse endometrial stromal cells†.

Uterine endometrial differentiation is essential for developmental continuity and female health. A convenient in vitro model mimicking the physiological status is needed to effectively evaluate implantation and uterine response mechanisms. Thus, we developed a promising in vitro model, the FSS (FSH mimic-stimulated synchronized) model, by using primary mouse uterine stromal cells (mUSCs) obtained from equine chorionic gonadotropin (eCG)-primed mice. These mUSCs could be differentiated into decidualized cells with 17 beta-estradiol (E2) and progesterone (P4). The pregnancy day 4 (PD4) model, in which mUSCs are obtained at day 4 of pregnancy, was used as a control. The cell shape index and polyploidy rates were similar between the two models. The staining intensities of lipids and glycogen were significantly higher in the induced groups in both models but stronger in the FSS model than in the PD4 model. The expression levels of AP-TNAP, cathepsin L, Prl8a2, Gja1, Cebpb, and Igfbp1 were increased at 24 h after decidual induction. PR-alpha and PR-beta levels were also increased at 24 h after decidual induction in both models. These results indicate that the FSS model provides a convenient method for obtaining USCs that are usable for various experimental approaches due to their physiological competence and flexibility for triggering induction. This may serve as a model system for the study of pathogeneses originating from the endometrium or communication with other tissues and lead to a better understanding of embryo implantation mechanisms. Furthermore, the results of this study will be integral for further refinements of 3D uterine culture manipulation techniques.

Fungal arthritis with adjacent osteomyelitis caused by Candida pelliculosa: a case report.

BACKGROUND: Candida sp. osteoarticular infection is rare and most often due to hematogenous seeding during an episode of candidemia in immunocompromised patients. However, the diagnosis can be delayed in patients with subtle symptoms and signs of joint infection without a concurrent episode of candidemia. CASE PRESENTATION: A 75-year-old woman presented with a three-year history of pain and swelling of the left knee. Candida pelliculosa was detected from the intraoperative tissue when the patient had undergone left total knee arthroplasty 32 months ago, but no antifungal treatment was performed. One year after the total knee arthroplasty, C. pelliculosa was repeatedly isolated from the left knee synovial fluid and antifungal treatment comprising amphotericin B deoxycholate and fluconazole was administered. However, joint infection had extended to the adjacent bone and led to progressive joint destruction. The patient underwent surgery for prosthesis removal and received prolonged antifungal treatment with micafungin and fluconazole. CONCLUSIONS: This case shows that C. pelliculosa, an extremely rare non-Candida albicans sp., can cause fungal arthritis and lead to irreversible joint destruction owing to delayed diagnosis and treatment.

On-Site Detection of Aflatoxin B1 in Grains by a Palm-Sized Surface Plasmon Resonance Sensor.

Aflatoxins (AFs) are highly toxic compounds that can cause both acute and chronic toxicity in humans. Aflatoxin B1 (AFB1) is considered the most toxic of AFs. Therefore, the rapid and on-site detection of AFB1 is critical for food safety management. Here, we report the on-site detection of AFB1 in grains by a portable surface plasmon resonance (SPR) sensor. For the detection of AFB1, the surface of an SPR Au chip was sequentially modified by cysteine-protein G, AFB1 antibody, and bovine serum albumin (BSA). Then, the sample solution and AFB1-BSA conjugate were flowed onto the Au chip in serial order. In the absence of AFB1, the SPR response greatly increased due to the binding of AFB1-BSA on the Au chip. In the presence of AFB1, the SPR response showed little change because the small AFB1 molecule binds on the Au chip instead of the large AFB1-BSA molecule. By using this portable SPR-based competitive immunoassay, the sensor showed low limits of detection (2.51 ppb) and quantification (16.32 ppb). Furthermore, we successfully detected AFB1 in rice, peanut, and almond samples, which suggests that the proposed sensing method can potentially be applied to the on-site monitoring of mycotoxins in food.

Molecular epidemiology of extended-spectrum ß-lactamase-producing Escherichia coli in the community and hospital in Korea: emergence of ST131 producing CTX-M-15.

BACKGROUND: The prevalence of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli has been increased not only in the hospital but also in the community worldwide. This study was aimed to characterize ESBL- producing E. coli isolates and to investigate the molecular epidemiology of community isolates in comparison with hospital isolates at a single center in Korea. METHODS: A total of 142 ESBL-producing E. coli isolates were collected at Daejeon St Mary's Hospital in Korea from January 2008 to September 2009. The ESBLs were characterized by PCR sequencing using specific primers. The genetic relatedness was determined by pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). RESULTS: Of 142 isolates, 139 were positive for CTX-M type ESBLs; CTX-M-14 (n = 69, 49.6 %), CTX-M-15 (n = 53, 38.1 %) and both CTX-M-14 and -15 (n = 17, 12.2 %). CTX-M-14 and CTX-M-15 were detected in both community and hospital isolates whereas isolates producing both CTX-M14 and-15 were mainly identified in the hospital. CTX-M producing E. coli isolates were genetically heterogeneous, revealing 75 distinct PFGE types. By MLST, 21 distinctive STs including 5 major STs (ST131, ST405, ST38, ST10, and ST648) were identified. Major STs were distributed in both community and hospital isolates, and ST131 was the predominant clone regardless of the locations of acquisition. No specific major STs were confined to a single type of ESBLs. However, ST131 clones were significantly associated with CTX-M-15 and the majority of them were multidrug-resistant. Distinctively, we identified a hospital epidemic caused by the dissemination of an epidemic strain, ST131-PFGE type 10, characterized by multidrug resistance and co-producing both CTX-Ms with OXA-1 or TEM-1b. CONCLUSIONS: The epidemiology of ESBL-producing E. coli is a complex and evolving phenomenon attributed to the horizontal transfer of genetic elements and clonal spread of major clones, predominantly ST131. The multidrug resistant ST131 clone producing CTX-M-15 has emerged as a major clone in both the community and hospital, suggesting the widespread of this epidemic clone in Korea.

Zwitterionic Polydopamine/Protein G Coating for Antibody Immobilization: Toward Suppression of Nonspecific Binding in Immunoassays.

For the development of immunoassays into sophisticated analyte-sensing methods, it is a priority to suppress nonspecific binding in immunoassays. Herein, we report a one-step surface coating method that can not only optimally immobilize antibodies but also suppress nonspecific binding. Zwitterionic dopamine (ZW-DOPA) exhibits distinct antifouling performance, and protein G enables an antibody to have an optimal orientation. A mixture of ZW-DOPA and protein G can be simply coated onto various kinds of surfaces, and the antibody can be immobilized onto the ZW-DOPA/protein G-coated surfaces. The antifouling property of the zwitterionic group, surface-independent coating property of the catechol and amine groups, and antibody-retaining property of protein G synergistically contribute to surface-independent and oriented immobilization of antibodies without nonspecific binding. The surface characteristics of ZW-DOPA/protein G-coated substrates were analyzed by X-ray photoelectron spectroscopy, contact angle goniometry, atomic force microscopy, and ellipsometry. Importantly, the ZW-DOPA/protein G-coated substrates showed high resistance to nonspecific protein adhesion. We also verified that antibodies could be immobilized onto ZW-DOPA/protein G-coated substrates using fluorescence and biolayer interferometry systems. Finally, ZW-DOPA/protein G-coated substrates were employed as immune substrates for influenza virus detection via the naked eye and surface-enhanced Raman scattering, allowing us to efficiently identify the virus. It is anticipated that the developed ZW-DOPA/protein G coating method will be useful for the advancement of immunoassays.

Surface-Independent and Oriented Immobilization of Antibody via One-Step Polydopamine/Protein G Coating: Application to Influenza Virus Immunoassay.

For the construction of high-performance biosensor, it is important to interface bioreceptors with the sensor surface densely and in the optimal orientation. Herein, a simple surface modification method that can optimally immobilize antibodies onto various kinds of surfaces is reported. For the surface modification, a mixture of polydopamine (PDA) and protein G was employed. PDA is a representative mussel-inspired polymer, and protein G is an immunoglobulin-binding protein that enables an antibody to have an optimal orientation. The surface characteristics of PDA/Protein G mixture-coated substrates are analyzed and the PDA/protein G ratio is optimized to maximize the antibody binding efficiency. Moreover, the antibody-immobilized substrates are applied to the detection of influenza viruses with the naked eye, providing a detection limit of 2.9 × 103 pfu mL-1 . Importantly, the several substrates (glass, SiO2 , Si, Al2 O3 , polyethylene terephthalate, polyethylene, polypropylene, and paper) can be modified by simple incubation with the mixture of PDA/protein G, and then the anti-influenza A H1N1 antibodies can be immobilized on the substrates successfully. Regardless of the substrate, the influenza viruses are detectable after the sandwich immunoreaction and silver enhancement procedure. It is anticipated that the developed PDA/protein G coating method will extend the range of applicable materials for biosensing.

Highly Sensitive in Vitro Diagnostic System of Pandemic Influenza A (H1N1) Virus Infection with Specific MicroRNA as a Biomarker.

Several microRNAs (miRNAs) have been reported to be closely related to influenza A virus infection, replication, and immune response. Therefore, the development of the infectious-disease detection system using miRNAs as biomarkers is actively underway. Herein, we identified two miRNAs (miR-181c-5p and miR-1254) as biomarkers for detection of pandemic influenza A H1N1 virus infection and proposed the catalytic hairpin assembly-based in vitro diagnostic (CIVD) system for a highly sensitive diagnosis; this system is composed of two sets of cascade hairpin probes enabling to detect miR-181c-5p and miR-1254. We demonstrated that CIVD kits could not only detect subnanomolar levels of target miRNAs but also distinguish even single-base mismatches. Moreover, this CIVD kit has shown excellent detection performance in real intracellular RNA samples and confirmed results similar to those of conventional methods (microarray and quantitative real-time polymerase chain reaction).

Health insurance literacy and awareness of the Affordable Care Act in a vulnerable Hispanic population.

OBJECTIVE: The Patient Protection and Affordable Care Act (ACA) has allowed millions of Americans to obtain coverage. However, many, especially minorities, remain uninsured. With mounting evidence supporting the importance of health insurance literacy (HIL), the purpose of this cross-sectional study is to examine the association between HIL and ACA knowledge. METHODS: We conducted 681 in-person interviews with participants at a community health event along the Texas-Mexico border in 2015, after the conclusion of the ACA's second enrollment period. To assess HIL, we used the Health Insurance Literacy Measure, reflecting consumers' confidence to choose, compare, and use health insurance. We assessed ACA knowledge through the following question: "How much would you say you know about this health reform law?" Logistic regression was used to examine the association between HIL and ACA knowledge after controlling for several covariates. RESULTS: Almost 70% of participants knew nothing/very little about the ACA. Multivariate analyses revealed that no/very little ACA knowledge was associated with low levels of confidence "choosing health insurance plans" (OR:0.55; 95%CI:0.40-0.75) (full sample) and "comparing plans" (OR:0.56; 95%CI:0.32-0.96) (U.S.-born sub-sample). CONCLUSION: No/little ACA knowledge is associated with lower levels of HIL. PRACTICE IMPLICATIONS: Promoting HIL is an essential step towards improving healthcare access.

Comparative evaluation of a newly developed 13-valent pneumococcal conjugate vaccine in a mouse model.

Animal models facilitate evaluation of vaccine efficacy at relatively low cost. This study was a comparative evaluation of the immunogenicity and protective efficacy of a new 13-valent pneumococcal conjugate vaccine (PCV13) with a control vaccine in a mouse model. After vaccination, anti-capsular antibody levels were evaluated by pneumococcal polysaccharide (PnP) enzyme-linked immunosorbent assay (ELISA) and opsonophagocytic killing assay (OPA). Also, mice were challenged intraperitoneally with 100-fold of the 50% lethal dose of Streptococcus pneumoniae. The anti-capsular IgG levels against serotypes 1, 4, 7F, 14, 18C, 19A, and 19F were high (quartile 2 >1,600), while those against the other serotypes were low (Q2 ≤ 800). Also, the OPA titres were similar to those determined by PnP ELISA. Comparative analysis between new PCV13 and control vaccination group in a mouse model exhibited significant differences in serological immunity of a few serotypes and the range of anti-capsular IgG in the population. Challenge of wild-type or neutropenic mice with serotypes 3, 5, 6A, 6B, and 9V showed protective immunity despite of induced relatively low levels of anti-capsular antibodies. With comparison analysis, a mouse model should be adequate for evaluating serological efficacy and difference in the population level as preclinical trial.

A Case of Spontaneous Bacterial Peritonitis with Bacteremia Caused by Shewanella algae.

Human infection caused by Shewanella algae is rare, which usually occurred after direct contact with seawater or ingestion of raw seafood in the immunocompromised host. There have been anecdotal reports about Shewanella infections in human, but their pathogenic role and microbiologic data are limited. Here, we report a fatal case of spontaneous bacterial peritonitis with bacteremia due to S. algae in a 57-year-old male with liver cirrhosis who had no history of exposure to seawater or raw seafood. Polymicrobial infection with Streptococcus mitis and Escherichia coli was combined and the patient died in spite of early appropriate antimicrobial therapy and early goal-directed therapy for sepsis.

Genetic diversity of the ftsI gene in ß-lactamase-nonproducing ampicillin-resistant and ß-lactamase-producing amoxicillin-/clavulanic acid-resistant nasopharyngeal Haemophilus influenzae strains isolated from children in South Korea.

Haemophilus influenzae frequently colonizes the nasopharynx of children and adults, which can lead to a variety of infections. We investigated H. influenzae carriage in the nasopharynx of 360 children, in terms of (1) the prevalence of strains with decreased susceptibility, and (2) the presence of amino acid substitutions in PBP3. One hundred twenty-three strains were isolated (34.2%, 123/360), 122 of which were classified as nontypable H. influenzae (NTHi). Of these, ß-lactamase-nonproducing ampicillin-susceptible strains accounted for 26.2%, ß-lactamase-producing-ampicillin-resistant strains for 9.0%, ß-lactamase-nonproducing ampicillin-resistant (BLNAR) strains for 40.2%, and ß-lactamase-producing amoxicillin-/clavulanic acid-resistant (BLPACR) for 24.6%, respectively. Pulsed field gel electrophoresis (PFGE) patterns were so diverse that they were clustered into 41 groups. The amino acid substitutions in the transpeptidase domain (292 amino acids) of ftsI in BLNAR isolates showed that group IIb accounted for 30.6%, IIc for 8.2%, IId for 16.3%, III for 32.7%, and the others for 12.2%. Moreover, groups IIb (56.7%; 17/30) and III (23.3%; 7/30) were prevalent among BLPACR strains. They were subclassified into more diverse sequence subtypes by analysis of the entire PBP3 (610 amino acids). Groups IIb, IIc, IId, and III exhibited 13, four, six, and four sequence subtypes, respectively. Such a genetic diversity is likely indicative of significant potential for decreased antimicrobial susceptibility in nasopharyngeal-colonizing NTHi strains.

Downregulation of RNAIII in vancomycin-intermediate Staphylococcus aureus strains regardless of the presence of agr mutation.

Reduced vancomycin susceptibility in Staphylococcus aureus can cause serious problems relating to treatment failure and persistent infection. We investigated vancomycin susceptibility, genetic relationships and transcriptional changes of the accessory gene regulator (agr) in vancomycin-intermediate S. aureus (VISA) strains isolated from South Korea compared with vancomycin-susceptible S. aureus (VSSA) strains. Molecular characterization, population analysis profiling, agr sequencing and transcriptional profiling of RNAIII by real-time RT-PCR were performed. Of 16 VISA strains tested, eight exhibited ST5, agr II and type II SCCmec. The others exhibited ST239, agr I and type III SCCmec. A point mutation in AgrA (Asp8Gly or Ile238Lys) was found in only five VISA strains; no mutations were detected in the other strains. However, RNAIII levels markedly decreased in all VISA strains (mean of 1.39-fold change) compared with the VSSA strains (31.51-fold change) in late-exponential phases (P<0.0001). The downregulation of RNAIII could be an important genetic event in the VISA strains, regardless of the presence or absence of the agr mutation.

Molecular epidemiology of vancomycin-resistant Enterococcus faecium bloodstream infections among patients with neutropenia over a 6-year period in South Korea.

Over a 6-year period (March 2000-February 2006), there were 60 vancomycin-resistant Enterococcus faecium (VREF) bloodstream infections (BSIs) in a hematology unit, accounting for 83.3% of all VREF BSIs in the hospital. We investigated 49 VREF isolates causing BSIs in patients with neutropenia to understand the molecular epidemiology at this unit. All isolates had the vanA genotype. Pulsed-field gel electrophoresis typing revealed high clonal diversity (23 types with nine clusters comprising 35 isolates) and 1 predominant type, type A (14/49, 28.6%), persisted at this unit throughout the study period, suggesting the clonal spread of this endemic strain by cross-contamination. Tn1546 types were less heterogeneous, with five main Tn1546 types, two of which (types I and IV) accounted for 67.4% of isolates. This indicates that in addition to clonal spread, the horizontal transfer of Tn1546 played a major role in the nosocomial dissemination of vancomycin resistance. The genetic diversity of VREF increased over time, implying an increasing influx of new strains into the unit and genetic changes, possibly attributable to the horizontal transfer of diverse Tn1546 types. Despite such diversity, all the isolates belonged to clonal complex 17, which is the epidemic clone worldwide, enriched with the esp (35/49, 71.4%) and hyl (24/49, 48.9%) virulence genes. This hospital-adapted clone has become endemic and is well suited to causing BSIs in patients with neutropenia in this unit.