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The century-long Michaelis-Menten rate law and its modifications in the modeling of biochemical rate processes stand on the assumption that the concentration of the complex of interacting molecules, at each moment, rapidly approaches an equilibrium (quasi-steady state) compared to the pace of molecular concentration changes. Yet, in the case of actively time-varying molecular concentrations with transient or oscillatory dynamics, the deviation of the complex profile from the quasi-steady state becomes relevant. A recent theoretical approach, known as the effective time-delay scheme (ETS), suggests that the delay from the relaxation time of molecular complex formation contributes to the substantial breakdown of the quasi-steady state assumption. Here, we systematically expand this ETS and inquire into the comprehensive roles of relaxation dynamics in complex formation. Through the modeling of rhythmic protein-protein and protein-DNA interactions and the mammalian circadian clock, our analysis reveals the effect of the relaxation dynamics beyond the time delay, which extends to the dampening of changes in the complex concentration with a reduction in the oscillation amplitude compared to the quasi-steady state. Interestingly, the combined effect of the time delay and amplitude reduction shapes both qualitative and quantitative oscillatory patterns such as the emergence and variability of the mammalian circadian rhythms. These findings highlight the downside of the routine assumption of quasi-steady states and enhance the mechanistic understanding of rich time-varying biomolecular processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Quantitative coronary angiography (QCA) offers objective and reproducible measures of coronary lesions. However, significant inter- and intra-observer variability and time-consuming processes hinder the practical application of on-site QCA in the current clinical setting. This study proposes a novel method for artificial intelligence-based QCA (AI-QCA) analysis of the major vessels and evaluates its performance., Methods: AI-QCA was developed using three deep-learning models trained on 7658 angiographic images from 3129 patients for the precise delineation of lumen boundaries. An automated quantification method, employing refined matching for accurate diameter calculation and iterative updates of diameter trend lines, was embedded in the AI-QCA. A separate dataset of 676 coronary angiography images from 370 patients was retrospectively analyzed to compare AI-QCA with manual QCA performed by expert analysts. A match was considered between manual and AI-QCA lesions when the minimum lumen diameter (MLD) location identified manually coincided with the location identified by AI-QCA. Matched lesions were evaluated in terms of diameter stenosis (DS), MLD, reference lumen diameter (RLD), and lesion length (LL)., Results: AI-QCA exhibited a sensitivity of 89% in lesion detection and strong correlations with manual QCA for DS, MLD, RLD, and LL. Among 995 matched lesions, most cases (892 cases, 80%) exhibited DS differences ≤10%. Multiple lesions of the major vessels were accurately identified and quantitatively analyzed without manual corrections., Conclusion: AI-QCA demonstrates promise as an automated tool for analysis in coronary angiography, offering potential advantages for the quantitative assessment of coronary lesions and clinical decision-making., Competing Interests: Declaration of competing interest Jihoon Kweon, Jung-Min Ahn, Young-Hak Kim report a relationship of consulting and advisory with Medipixel. All other authors declare no conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Although not as common as solitary lesions, multiple schwannomas do occur, even in single nerve lesions. We report a rare case of a 47-year-old female patient who presented with multiple schwannomas with inter-fascicular invasion in the ulnar nerve above the cubital tunnel. Preoperative MRI revealed a 10-cm multilobulated tubular mass along the ulnar nerve above the elbow joint. During excision under 4.5° loupe magnification, we separated three ovoid yellow-colored neurogenic tumors of different sizes, but there were still remaining lesions as it was difficult to completely separate lesions from the ulnar nerve due to the risk of iatrogenic nerve ulnar nerve injury. The operative wound was closed. Postoperative biopsy confirmed the diagnosis of the three schwannomas. During the follow-up, the patient recovered without neurological symptom or limitations in range of motion, and there were no neurological abnormalities. At 1year after surgery, small lesions remained in the most proximal part. However, the patient had no clinical symptoms and was satisfied with the surgical results. Although a long-term follow-up is necessary for this patient, we were able to obtain good clinical and radiological results., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Interaction between tumour cells and macrophages enables cancer cells to evade immune detection and clearance by interfering with macrophage phagocytosis. The anti-phagocytic signals regulated by anti-phagocytic proteins are termed "don't eat me" signals; these signals include sialic acid-binding immunoglobulin-type lectin-10 (Siglec-10) and the recently revealed CD24 immune checkpoint (ICP). In this study, we demonstrate that targeting a specific glycan on CD24 exhibits the potential to inhibit ICP. Sambucus nigra agglutinin (SNA), a sialic acid-binding lectin, was employed to block CD24 and to enhance phagocytosis in melanoma tumours. In addition, we prepared SNA-conjugated hollow gold-iron oxide nanoparticles for photothermal therapy of tumours. Our findings show that the combination treatment of SNA-conjugated photothermal nanoparticles and near-infrared exposure successfully augments tumour cell phagocytosis both in vitro and in vivo models., Competing Interests: The authors declare no conflicts of interest., (© 2023 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

Objective: The Korean government published the first National Action Plan (NAP) on antimicrobial resistance (AMR) in August 2016, followed by a second plan in November 2021. The objective of this study was to analyze changes in antibiotic use patterns after the implementation of the NAP in South Korea., Methods: We analyzed National Health Insurance claims data for hospitals and clinics from January 2011 to December 2020. Consumption was measured using a defined daily dose per 1000 inhabitants per day (DID). We analyzed data for each year, dimension, and category of the Access, Watch, Reserve classification system by the World Health Organization. Monthly inpatient and outpatient antibiotic use were calculated, and an interrupted time-series (ITS) analysis to assess the trend in antibiotic use was conducted., Results: The consumption of antibiotics increased from 25.78 DID in 2011 to 29.06 DID in 2016, then decreased in 2017 after the implementation of the NAP on AMR. The watch group showed a temporal decrease after the implementation of the NAP; however, these figures increased until 2019, and the reserve group showed a downward trend beginning in 2017. According to the ITS analysis, the level (β 2 ) and the slope of the trend (β 3 ) of total antibiotic use decreased by 0.17 and 0.001, respectively. After implementation of the NAP, antibiotic use was reduced from 7.18 DID in 2016 to 4.84 DID in 2017 for amoxicillin and beta-lactamase inhibitors, 0.86 DID to 0.70 DID for ciprofloxacin, and 0.66 DID to0.66 DID for levofloxacin., Conclusion: After the implementation of the NAP in South Korea, antibiotic use in terms of total antibiotics and fluoroquinolone in the watch and reserve groups decreased. Further policies to improve the use of antibiotics in the watch and reserve groups are needed., Competing Interests: Conflict of interest statements The authors have no competing interests to declare., (Copyright © 2022. Published by Elsevier Ltd.)

Objectives: The role of overcrowded and multigenerational households as a risk factor for COVID-19 remains unmeasured. The objective of this study is to examine and quantify the association between overcrowded and multigenerational households and COVID-19 in New York City (NYC)., Study Design: Cohort study., Methods: We conducted a Bayesian ecological time series analysis at the ZIP Code Tabulation Area (ZCTA) level in NYC to assess whether ZCTAs with higher proportions of overcrowded (defined as the proportion of the estimated number of housing units with more than one occupant per room) and multigenerational households (defined as the estimated percentage of residences occupied by a grandparent and a grandchild less than 18 years of age) were independently associated with higher suspected COVID-19 case rates (from NYC Department of Health Syndromic Surveillance data for March 1 to 30, 2020). Our main measure was an adjusted incidence rate ratio (IRR) of suspected COVID-19 cases per 10,000 population. Our final model controlled for ZCTA-level sociodemographic factors (median income, poverty status, White race, essential workers), the prevalence of clinical conditions related to COVID-19 severity (obesity, hypertension, coronary heart disease, diabetes, asthma, smoking status, and chronic obstructive pulmonary disease), and spatial clustering., Results: 39,923 suspected COVID-19 cases were presented to emergency departments across 173 ZCTAs in NYC. Adjusted COVID-19 case rates increased by 67% (IRR 1.67, 95% CI = 1.12, 2.52) in ZCTAs in quartile four (versus one) for percent overcrowdedness and increased by 77% (IRR 1.77, 95% CI = 1.11, 2.79) in quartile four (versus one) for percent living in multigenerational housing. Interaction between both exposures was not significant (β interaction  = 0.99, 95% CI: 0.99-1.00)., Conclusions: Overcrowdedness and multigenerational housing are independent risk factors for suspected COVID-19. In the early phase of the surge in COVID cases, social distancing measures that increase house-bound populations may inadvertently but temporarily increase SARS-CoV-2 transmission risk and COVID-19 disease in these populations., (Copyright © 2021 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)

Background: Many studies on the relation between maternal health and infant health, including the effect of structured antenatal education, have been published and expanded over the years., Aim: Investigate the impact of various antenatal education programmes on pregnancy outcomes to aid the development of future guidelines related to maternal and foetal health., Methods: Bibliographic databases (Cochrane, PubMed, EMBASE, CINAHL, Korean Studies Information Service System) were searched up to November 2018, following the PICO criteria: population (pregnant women), intervention (antenatal education), comparison (not specified), and outcome (maternal and foetal outcome including physical or mental health components)., Findings: We included 23 eligible studies consisting of 14 controlled trials and 9 observational studies. The maternal physical outcomes depending on participation in antenatal education were not significantly different; however, the caesarean birth rate was lower in the antenatal education group (relative risk, RR, 0.90; 95% confidence interval, CI, 0.82-0.99), as was the use of epidural anaesthesia (RR, 0.84; 95% CI, 0.74-0.96). The maternal mental health outcomes of stress and self-efficacy significantly improved in the antenatal education group, although there was no difference in anxiety and depression. The foetal outcomes of birth weight or gestational age at birth were also not different between the groups., Conclusion: Antenatal education can reduce maternal stress, improve self-efficacy, lower the caesarean birth rate, and decrease the use of epidural anaesthesia; however, there is limited evidence of its effects on maternal or foetal physical outcomes. Therefore, antenatal education should be standardised to elucidate its actual mental and physical health effects., (Copyright © 2020 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.)

All aspects of medical education were affected by the COVID-19 pandemic. Several challenges were experienced by trainees and programs alike, including economic repercussions of the pandemic; social distancing affecting the delivery of medical education, testing, and interviewing; the surge of patients affecting redeployment of personnel and potential compromises in core training; and the overall impact on the wellness and mental health of trainees and educators. The ability of medical teams and researchers to peer review, conduct clinical research, and keep up with literature was similarly challenged by the rapid growth in peer-reviewed and preprint literature. This article reviews these challenges and shares strategies that institutions, educators, and learners adopted, adapted, and developed to provide quality education during these unprecedented times., (Copyright © 2020 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Competing Interests: Declaration of Competing Interest The authors report no declarations of interest.

Nemopilema nomurai venom (NnV) is severely toxic to many organisms. However, the mechanism of its poisoning has not been properly understood yet. The present work demonstrates that zebrafish (Danio rerio) is an alternative vertebrate model for studying NnV jellyfish venom for the first time. In this model, NnV appears to cause severe hemorrhage and inflammation in cardiopulmonary regions of zebrafish. NnV also altered the swimming behavior of zebrafish accompanied by a significant downregulation of acetylcholinesterase (AChE) activity in brain tissues. Histopathological changes observed for various organs of D. rerio caused by NnV corresponded to an increase in lactate dehydrogenase (LDH) activity in tissues. NnV also significantly altered glutathione S-transferase (GST) activity in cardiopulmonary and brain tissues of D. rerio. SDS-PAGE revealed many protein bands of NnV of various sizes after silver staining. Taken together, these results indicate that Danio rerio can be a useful alternative animal model for jellyfish venom toxicology studies. Findings of the present study also suggest that Danio rerio could be used to develop an effective treatment strategy and discover the mechanism of action of jellyfish venom envenomation., Competing Interests: Declaration of Competing Interest The authors report no declarations of interest., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Chiari malformation (CM) is often comorbid with syringomyelia. The treatment of CM via posterior fossa decompression (PFD) may not improve syringomyelia in up to 40% of patients, based on historical cohorts. Management of these patients is problematic, as both reoperation and syrinx shunting have high failure rates in the long term., Methods: We retrospectively reviewed our cases in which patients with CM type 1 or 1.5 and syringomyelia underwent PFD without postoperative improvement in syringomyelia. Symptomatology and radiographic measurements were collected at presentation and on the first and latest available postoperative scans and analyzed. We present 2 cases to illustrate the challenges in the management of these patients., Results: Our cohort consisted of 48 consecutive patients with CM and syringomyelia who underwent PFD. Of these, 41 patients had postoperative improvement in or resolution of syringomyelia. We subsequently studied the cohort of 7 patients who underwent PFD with (n = 5) or without (n = 2) durotomy and demonstrated worsening of syringomyelia following surgery. This cohort had mean (±SEM) preoperative syrinx area of 23.9 ± 10.0 mm 2 . Postoperatively, the mean syrinx area increased to 40.5 ± 9.6 mm 2 and 57.3 ± 12.5 mm 2 on the first and latest postoperative scans available (P = 0.02), for an increase of 106.9% ± 94.4% and 186.0% ± 107.4% (P = 0.04). Presenting symptoms included occipital headache, paresthesias, visual deterioration, and paraspinal pain. On last follow-up (mean 13.9 ± 4.9 months), the majority of symptoms were resolved in this cohort, despite persistence of syringomyelia., Conclusions: In this small cohort of unique patients, syrinx resolution was not achieved via decompression surgery. Despite "radiographic failure," good symptom control was achieved, with most patients remaining or becoming asymptomatic postoperatively, thus supporting our rationale for what has largely been a conservative approach in this population., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hepatobiliary cancers are among the leading causes of cancer-related deaths worldwide. Most of the early-stage, surgically resectable cases show recurrence, and when they do, the prognosis is dismal with limited available treatment options. Here, we report three patients with relapsed hepatobiliary cancers who presented relatively long progression-free survival with the administration of a natural product, allergen removed Rhus verniciflua Stokes (RVS) extract. After commencement of RVS extract, they were progression-free for over 56 months in one case of recurred cholangiocarcinoma, and for over 16 and 114 months respectively, in two cases of advanced hepatocellular carcinoma. These cases suggest that the RVS extract could be a potential alternative for advanced hepatobiliary cancer that has no other available treatment., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphomas (EBV + -DLBLs) tend to occur in immunocompromised patients, such as the elderly or those undergoing solid organ transplantation. The pathogenesis and genomic characteristics of EBV + -DLBLs are largely unknown because of the limited availability of human samples and lack of experimental animal models. We observed the development of 25 human EBV + -DLBLs during the engraftment of gastric adenocarcinomas into immunodeficient mice. An integrated genomic analysis of the human-derived EBV + -DLBLs revealed enrichment of mutations in Rho pathway genes, including RHPN2 , and Rho pathway transcriptomic activation. Targeting the Rho pathway using a Rho-associated protein kinase (ROCK) inhibitor, fasudil, markedly decreased tumor growth in EBV + -DLBL patient-derived xenograft (PDX) models. Thus, alterations in the Rho pathway appear to contribute to EBV-induced lymphomagenesis in immunosuppressed environments., (© 2018 by The American Society of Hematology.)

Objective: Percutaneous peripheral nerve stimulation (PNS) is an FDA-cleared pain treatment. Occasionally, fragments of the lead (MicroLead, SPR Therapeutics, LLC, Cleveland, OH, USA) may be retained following lead removal. Since the lead is metallic, there are associated magnetic resonance imaging (MRI) risks. Therefore, the objective of this investigation was to evaluate MRI-related issues (i.e., magnetic field interactions, heating, and artifacts) for various lead fragments., Methods: Testing was conducted using standardized techniques on lead fragments of different lengths (i.e., 50, 75, and 100% of maximum possible fragment length of 12.7 cm) to determine MRI-related problems. Magnetic field interactions (i.e., translational attraction and torque) and artifacts were tested for the longest lead fragment at 3 Tesla. MRI-related heating was evaluated at 1.5 Tesla/64 MHz and 3 Tesla/128 MHz with each lead fragment placed in a gelled-saline filled phantom. Temperatures were recorded on the lead fragments while using relatively high RF power levels. Artifacts were evaluated using T1-weighted, spin echo, and gradient echo (GRE) pulse sequences., Results: The longest lead fragment produced only minor magnetic field interactions. For the lead fragments evaluated, physiologically inconsequential MRI-related heating occurred at 1.5 Tesla/64 MHz while under certain 3 Tesla/128 MHz conditions, excessive temperature elevations may occur. Artifacts extended approximately 7 mm from the lead fragment on the GRE pulse sequence, suggesting that anatomy located at a position greater than this distance may be visualized on MRI., Conclusions: MRI may be performed safely in patients with retained lead fragments at 1.5 Tesla using the specific conditions of this study (i.e., MR Conditional). Due to possible excessive temperature rises at 3 Tesla, performing MRI at that field strength is currently inadvisable., (© 2017 International Neuromodulation Society.)

Objective: To explore the feasibility and safety of a single-lead, fully implantable peripheral nerve stimulation system for the treatment of chronic shoulder pain in stroke survivors., Participants: Participants with moderate to severe shoulder pain not responsive to conservative therapies for six months., Methods: During the trial phase, which included a blinded sham introductory period, a percutaneous single-lead peripheral nerve stimulation system was implanted to stimulate the axillary nerve of the affected shoulder. After a three-week successful trial, participants received an implantable pulse generator with an electrode placed to stimulate the axillary nerve of the affected shoulder. Outcomes included pain, pain interference, pain-free external rotation range of motion, quality of life, and safety. Participants were followed for 24 months., Results: Twenty-eight participants underwent trial stimulation and five participants received an implantable pulse generator. The participants who received the implantable generator experienced an improvement in pain severity (p = 0.0002). All five participants experienced a 50% or greater pain reduction at 6 and 12 months, and four experienced at least a 50% reduction at 24 months. There was an improvement in pain interference (p < 0.0001). There was an improvement in pain-free external ROM (p = 0.003). There were no serious adverse events related to the device or to the procedure., Conclusions: This case series demonstrates the safety and efficacy of a fully implantable axillary PNS system for chronic HSP. Participants experienced reduction in pain, reduction in pain interference, and improved pain-free external rotation ROM. There were no serious adverse events associated with the system or the procedure., (© 2017 International Neuromodulation Society.)

Objective: The objective of this study was to determine the effect of peripheral nerve stimulation (PNS) on pain reduction for those with refractory subacromial impingement syndrome (SIS) and to evaluate the association with reduced disability, impairment, and safety. Our hypotheses are that PNS will be associated with a reduction in pain, impairment and disability, and improvement in quality of life while demonstrating safety., Material and Methods: Adults with shoulder pain of at least six months duration were recruited for a three-week treatment of percutaneous PNS applied through a percutaneous electrode to the axillary motor points of the deltoid muscle. Subjects were followed for 12 weeks after treatment. The primary outcome was the worst pain in the last week, and secondary outcomes included pain interference, the Disabilities of the Arm, Shoulder, and Hand questionnaire, shoulder abduction range of motion, and safety. Analysis was with a linear mixed model., Results: Ten subjects were recruited. Longitudinal analysis demonstrated significant reduction in pain relative to baseline (F(1, 66) = 12.9, p < 0.01). After correcting for multiple comparisons, there were significant reductions at explantation and all follow-up time points when compared with baseline. There were also significant improvements in pain interference (F(1,65) = 15.0, p < 0.01), the Disabilities of the Arm, Shoulder, and Hand questionnaire (F(1,35) = 7.0, p = 0.01), and shoulder abduction range of motion (F(1,35) = 6.3, p = 0.02)., Conclusion: Intramuscular PNS for chronic shoulder pain due to SIS is a safe treatment associated with pain reduction, lower pain interference with activities of daily living, reduced disability, and improved shoulder abduction. Pain reduction is maintained for at least 12 weeks after treatment., (© 2014 International Neuromodulation Society.)

Named entities in the biomedical domain are often written using a Noun Phrase (NP) along with a coordinating conjunction such as 'and' and 'or'. In addition, repeated words among named entity mentions are frequently omitted. It is often difficult to identify named entities. Although various Named Entity Recognition (NER) methods have tried to solve this problem, these methods can only deal with relatively simple elliptical patterns in coordinated NPs. We propose a new NER method for identifying non-elliptical entity mentions with simple or complex ellipses using linguistic rules and an entity mention dictionary. The GENIA and CRAFT corpora were used to evaluate the performance of the proposed system. The GENIA corpus was used to evaluate the performance of the system according to the quality of the dictionary. The GENIA corpus comprises 3434 non-elliptical entity mentions in 1585 coordinated NPs with ellipses. The system achieves 92.11% precision, 95.20% recall, and 93.63% F-score in identification of non-elliptical entity mentions in coordinated NPs. The accuracy of the system in resolving simple and complex ellipses is 94.54% and 91.95%, respectively. The CRAFT corpus was used to evaluate the performance of the system under realistic conditions. The system achieved 78.47% precision, 67.10% recall, and 72.34% F-score in coordinated NPs. The performance evaluations of the system show that it efficiently solves the problem caused by ellipses, and improves NER performance. The algorithm is implemented in PHP and the code can be downloaded from https://code.google.com/p/medtextmining/., (Copyright © 2013. Published by Elsevier Inc.)

Background and Aim: Since using LDL level alone is insufficient as a method to identify individuals with incident coronary artery disease (CAD), other factors may be implicated in the pathogenesis of CAD. Additionally, controversy still remains regarding whether there is an age-related increase in circulating cytokines in healthy individuals. We investigated the influence of age on atherogenicity of LDL and inflammatory markers in healthy women., Methods and Results: Two thousand nine hundred forty four healthy women form 30-79 years old (23.3 ± 0.05 kg/m²) were categorized into 5 age groups: 30-39, 40-49, 50-59, 60-69 and 70-79 years. BMI, smoking, drinking, and metabolic syndrome prevalence adjusted mean values of total-cholesterol progressively increased from the group age 30-39 years to the group age 40-49 and 50-59 years and thereafter decreased in the group age 60-69 and 70-79 years. Serum concentrations of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were higher in women aged 60-79 years than women aged 30-59 years. Plasma ox-LDL levels increased in the group age 50-59 years compared with the group age 30-39 and 40-49 years and further increased in the group age 60-69 and 70-79 years. Mean values of LDL particle size were smaller in women aged 60-79 years than those in women aged 30-59 years. After adjustment for BMI, smoking, drinking, and metabolic syndrome status, age was positively correlated with LDL-cholesterol (r = 0.095, P < 0.001), oxidized LDL (r = 0.305, P < 0.001), hs-CRP (r = 0.150, P < 0.001), TNF-α (r = 0.171, P < 0.001) and IL-6 (r = 0.294, P < 0.001) and negatively with LDL particle size (r = -0.239, P < 0.001)., Conclusion: Our results indicate that LDL atherogenicity and inflammatory mediators can be better markers of CAD risk than known risk factors such as elevated concentrations of total- and LDL-cholesterol, decreased HDL-cholesterol levels and smoking in old healthy women., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The birth rate of cloned animals following somatic cell nuclear transfer (SCNT) is very low and the surviving animals have various developmental defects. We compared the morphology and transcriptional profile of extraembryonic tissue from three 26-d old SCNT pig fetuses with that from control fetuses. Transcriptional profiling using long-oligonucleotide microarray technology revealed 34 genes that were differentially expressed between the three groups. The differential expression of several genes involved in translational regulation was confirmed by real-time quantitative PCR and Western blot analysis. Interestingly, the expression of a translational inhibition-related gene encoding a eukaryotic translation initiation factor 4E-binding protein was significantly elevated in the SCNT samples. We concluded that the low birth rate of cloned animals could be related to abnormal expression of translational regulators in extraembryonic tissue during early pregnancy.

Running loops have been used in mandibular second premolar extraction treatment instead of cherry or shoehorn closing loops in the Tweed technique. They can also be used when molar extraction patterns are unusual or if molars are missing or hopeless, or have extensive restorations. A running loop archwire is usually made of 0.018 x 0.025-in stainless steel, with a helical loop 5 mm mesial to the buccal tube. The effective tipback is usually about 20 degrees to 30 degrees to upright molars, and a slight toe-in is necessary to prevent mesiolingual rotation. As the extraction space closes, the distance between the running loop and the buccal tube is shortened. Then a helical loop can be moved mesially to maintain the distance and the force between them by simple archwire manipulation. Consequently, the extraction space can be closed with 1 running loop archwire after initial leveling.

The distribution of ciliate plankton was compared between inner and outer areas of a harbor divided by an artificial breakwater in Kuryongpo, on the eastern coast of Korea, from February 2001 to October 2003. Less dissolved oxygen and higher concentrations of nitrogenous nutrients and phosphate were observed in the inner area. The abundance of oligotrich ciliates peaked in February 2001, when nanoflagellates bloomed in the inner area. The photosynthetic ciliate Mesodinium rubrum showed differing population dynamics annually, with blooming peaks in October 2001 in the inner area and in February 2003 in the outer area. The tintinnid species Tintinnopsis beroidea and Helicostomella subulata were generally more abundant in the outer area. Total ciliates were significantly related to oligotrich abundance in the inner area, and to tintinnid abundances in the outer area. Ciliate distribution showed quantitative and qualitative differences between the inner and outer areas in connection with the distribution of other plankton communities: oligotrich ciliate abundance increased with nanoflagellate blooms; dominance of M. rubrum was consistent with blooming of micro-sized phytoplankton (diatoms and dinoflagellates); large-sized tintinnids concurred with small dinoflagellates; and ciliate abundances decreased with mesozooplankton increases. The results indicate that the breakwater induces eutrophication in the inner area and provides suitable conditions for nanoflagellate blooms, which serially trigger opportunistic increases in oligotrich ciliates.

Purpose: To investigate the clinical manifestations and ocular findings in children with ocular myasthenia gravis (MG) that rarely have been reported in the literature., Design: Retrospective, noncomparative case series., Participants: Twenty-four consecutive patients less than 15 years of age with ocular MG treated between June 1988 and July 2001., Methods: The medical records of 6 boys and 18 girls with ocular MG were reviewed retrospectively., Main Outcome Measures: Alternate prism cover and uncover test, examination of ductions and versions, and visual acuity., Results: Mean age at onset was 38 months. Ptosis was found in 23 patients (96%), strabismus in 21 patients (88%), and amblyopia in 5 patients (21%). Exotropia combined with vertical heterotropia was the most frequent type of strabismus. Ductions were limited in 17 patients (71%), among whom supraduction or infraduction limitations were most frequently observed. Contrary to previous reports, medial rectus underaction was less common than lateral rectus underaction. Manifestations of strabismus and limitation of duction were variable and changed frequently during the follow-up period. The combined use of prednisone and pyridostigmine was found to be the predominant form of maintenance therapy, and ptosis was more responsive to drug therapy than limited ocular motility., Conclusions: Children with ocular MG were found to have a high incidence of ptosis (96%) and exotropia and vertical hyperdeviation. Limitation on adduction was less common than that on abduction. First reported incidence of amblyopia (21%) and a relative nonresponsiveness of the limitation of eye movement to treatment were also noted.

Rhodococcus equi is an opportunistic pathogen that usually causes infection in immunocompromised hosts. A heart transplant recipient who had been treated with amphotericin B for pulmonary aspergillosis showed newly developed multiple nodules with a central necrotic area in the right lower lobes. Cultures of several blood samples and an aspirate of the lung nodule yielded a Gram-positive coccobacillary bacterium, which was initially reported as a Corynebacterium species, but was later identified as R. equi by API CORYNE (bioMerieux SA, Marcy l'Etoile, France) and by demonstrating the production of 'equi factor'. The identification was subsequently confirmed by an R. equi-specific polymerase chain reaction (PCR). The patient was successfully treated with ciprofloxacin and azithromycin for 14 weeks. This is the first documented case of R. equi infection in Korea. There is a possibility of underestimation of R. equi infections due to the misidentification of the organism as a contaminating diphtheroid. Because R. equi will not respond to the conventional empirical therapy, the microbiology laboratory should identify R. equi in a timely manner. R. equi-specific PCR will be a useful confirmatory test in human infection.

Analysis of gene function in vertebrates is facilitated by gain-of-function studies, such as injection of synthetic mRNA in amphibian embryos. This approach is hampered by lack of spatial and temporal control of expression of the introduced gene product. An additional level of control is obtained by nuclear-transfer-mediated transgenesis, but functional analyses are complicated by variability and background abnormalities in primary transgenic embryos. The GAL4/UAS system permits establishment of stable lines and elimination of nuclear-transfer-associated abnormalities, through generation of separate UAS-'effector' and GAL4 'transactivator' transgenic lines. When the GAL4 DNA-binding domain is combined with a steroid hormone ligand-binding domain, this system allows full temporal regulation of transgene expression by introduction of an exogenous steroid analogue, the progesterone antagonist RU486. We show here that by crossing stable Xenopus tropicalis transgenic lines, one bearing a UAS-enhanced cyan fluorescent protein (ECFP) reporter construct, and the other with a GAL4-progesterone receptor fusion driven by a retina-specific promoter, reporter expression in the resulting embryos can be induced with RU486 in a tissue-specific manner. These results suggest that the inducible binary system, in which the target gene expression can be controlled in a stage- and tissue-specific pattern, should be readily applicable for gene function studies at all stages of development., (Copyright 2002 Elsevier Science Ireland Ltd.)

To better define seizure characteristics and to examine whether semiological seizure classification (SSC) can be appropriately applied to the seizures of infants and children, we studied 152 videotaped seizures recorded in 133 children. Seizure semiology was described on the basis of a series of behavioural, sensory, and motor phenomena according to SSC. Special emphasis was placed on whether one semiology can be representative of a patient's whole semiology sequence. If one semiology was able to represent the whole sequence, the seizure was classified according to SSC. Ninety of 152 seizures (59.2%) could be classified as a single seizure type by SSC. However, only 19 of 53 seizures (35.9%) consisting of two semiologies, three of 24 seizures (12.5%) consisting of three semiologies, and one of eight seizures (12.5%) consisting of four semiologies could be classified according to SSC. Although SSC is very efficient, it is more accurately a descriptive terminology for clinical ictal events than a classification system., (Copyright 2002 Published by Elsevier Science Ltd on behalf of BEA Trading Ltd.)

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever and intense inflammation. FMF attacks are unique in their sensitivity to the microtubule inhibitor colchicine, contrasted with their refractoriness to the anti-inflammatory effects of glucocorticoids. The FMF gene, MEFV, was recently identified by positional cloning; it is expressed at high levels in granulocytes and monocytes. The present study investigated the subcellular localization of the normal gene product, pyrin. These experiments did not support previously proposed nuclear or Golgi localizations. Instead fluorescence microscopy demonstrated colocalization of full-length GFP- and epitope-tagged pyrin with microtubules; this was markedly accentuated in paclitaxel-treated cells. Moreover, immunoblot analysis of precipitates of stabilized microtubules with recombinant pyrin demonstrated a direct interaction in vitro. Pyrin expression did not affect the stability of microtubules. Deletion constructs showed that the unique N-terminal domain of pyrin is necessary and sufficient for colocalization, whereas disease-associated mutations in the C-terminal B30.2 (rfp) domain did not disrupt this interaction. By phalloidin staining, a colocalization of pyrin with actin was also observed in perinuclear filaments and in peripheral lamellar ruffles. The proposal is made that pyrin regulates inflammatory responses at the level of leukocyte cytoskeletal organization and that the unique therapeutic effect of colchicine in FMF may be dependent on this interaction. (Blood. 2001;98:851-859)

With the long-term goal of generating CMV-resistant transgenic plants using antibody genes, a single-chain variable fragment (scFv) antibody that binds to the cucumber mosaic virus was isolated from a scFv phage display library by four rounds of affinity selection with CMV-Mf as an antigen. The scFv has the identical binding specificity to CMV as a monoclonal antibody that is generated by the hybridoma fusion technique, and recognized purified preparations of CMV isolates belonging to either subgroup I or II in immunoblotting. The nucleotide sequences of the recombinant antibody showed that a heavy chain variable region (V(H)) gene belonged to the VH3 subgroup and the kappa light chain variable region (V kappa) came from the Vkappa4 subgroup. Our results demonstrate that the scFv phage display library, an alternative approach to the traditional hybridoma fusion technique, has a potential applicability in the study of plant virus and plant pathology.

Ehrlichia DNA was identified by nested PCR in rainbow trout (Oncorhynchus mykiss) collected from a creek in northern California where Potomac horse fever is endemic. Ehrlichia DNA was found in tissues from several organs including the gills, heart, spleen, liver, kidneys and intestine of trout and from three different adult digenetic trematodes (Deropegus sp., Crepidostomum sp., Creptotrema sp.) parasitizing the gallbladder and/or the intestine of the trout. Sequencing of PCR-amplified DNA from the 16S rRNA gene indicated that the source organism was most closely related to the sequences of E. risticii (level of sequence similarity 96.0%), the SF agent (95.9%), E. sennetsu (95.8%), and Neorickettsia helminthoeca (95.3%). The data suggest that trout and parasitic trematodes may be involved in the epidemiology of an Ehrlichia-like agent belonging to the E. sennetsu genogroup. Whether the fish agent infects horses, dogs, or human beings, and whether it causes disease, remain to be determined.

Juga yrekaensis freshwater snails were tested for trematode stages and for Ehrlichia risticii DNA using a nested PCR assay. Snails were collected monthly from two Potomac horse fever (PHF) endemic locations in northern California (Montague and Weed). The trematode infection rate varied between 40 and 93.3% in large snails (shell size >15mm) and between 0 and 13.3% in small snails (<15mm). The highest trematode infection rate for large and small snails was recorded in September and the lowest infection rate for large snails was recorded in June (Weed) and October (Montague). The E. risticii PCR infection rate among small snails from both sites was similar and varied monthly between 0 and 3.3%. The PCR infection rate for large snails from Weed was high in May (20.0%) and decreased progressively until November (10.0%). The PCR infection rate for large snails from Montague was 5.0% in May, 26.3% in August and 16. 7% in October. PCR-positive snails were always related to the microscopic detection of trematode stages (virgulate cercariae). This study provides evidence that J. yrekaensis are infected with trematode cercariae that harbor E. risticii. The number of snails harboring trematode stages and the number of PCR positive snails varied with the size of the snails, the month of collection, and the geographic origin.

Recent advances in the study of globin gene switching in the context of complete gene locus have contributed greatly to our understanding of developmental regulation mechanism of globin gene expression. However, it is not clear yet whether the cluster is sufficient in proper gene switching when the globin genes are replaced with conventional reporter genes. Furthermore, even though erythroid-specific and ubiquitous transcription factors involved in erythroid-specific globin gene expression have been characterized and some plausible globin gene switching models have been suggested, any specific factor directly involved in globin gene switching is not yet identified. In this study, as an effort to further understand globin switching mechanism and to identify globin switching factors, we constructed reporter vectors by juxtaposing several putative regulatory elements in human beta-globin locus to conventional reporter genes and analyzed their stage-specific expression in erythroid cell lines. At the end, we demonstrated that gammabeta-type constructs, in which both gamma-type and beta-type globin reporter genes were linked in cis below beta-globin locus control region (LCR), show proper stage-specific reporter gene expression in erythroid cell lines and also recapitulate globin switching in cell hybrids.

A real-time quantitative PCR using the TaqMan fluorogenic detection system (TaqMan PCR) was established for identification of Ehrlichia risticii, the agent of Potomac horse fever (PHF). The TaqMan PCR identified an 85 base pair section of the 16S rRNA gene by use of a specific fluorogenic probe and two primers. This technique was specific for eight tested E. risticii strains. The TaqMan system identified 10 copies of a cloned section of the 16S rRNA gene of E. risticii. The sensitivity and specificity of the TaqMan PCR were similar to those of conventional nested PCR. The TaqMan PCR was evaluated on horses with infectious colitis and on freshwater stream snails collected from regions with a history of PHF. E. risticii could be detected in 22 of 153 (14.4%) horses with infectious colitis and in 25 of 234 (10.7%) snails in the TaqMan PCR. The same results were obtained in the conventional nested PCR. The Ehrlichia-load was in the range of 10,000-9,000,000 and 35,000-680, 000,000 Ehrlichia equivalents per microg leukocyte DNA and snail DNA, respectively.

The gene for the most common form of autosomal dominant polycystic kidney disease (ADPKD), PKD1, has recently been characterized and shown to encode an integral membrane protein, polycystin-1, which is involved in cell-cell and cell-matrix interactions. Until now, approximately 30 mutations of the 3' single copy region of the PKD1 gene have been reported in European and American populations. However, there is no report of mutations in Asian populations. Using the polymerase chain reaction and single-strand conformation polymorphism (SSCP) analysis, 91 Korean patients with ADPKD were screened for mutation in the 3' single copy region of the PKD1 gene. As a result, we have identified and characterized six mutations: three frameshift mutations (11548del8bp, 11674insG and 12722delT), a nonsense mutation (Q4010X), and two missense mutations (R3752W and D3814N). Five mutations except for Q4010X are reported here for the first time. Our findings also indicate that many different mutations are likely to be responsible for ADPKD in the Korean population. The detection of additional disease-causing PKD1 mutations will help in identifying the location of the important functional regions of polycystin-1 and help us to better understand the pathophysiology of ADPKD.

The transcription factor CP2 was initially identified to bind to the promoter region of the murine alpha-globin gene and known to stimulate the expression of alpha-globin by increasing CP2 transcripts 3- to 5-fold during induced differentiation of mouse erythroleukemic (MEL) cells in vitro. Here, we report that this increment of CP2 expression is crucial in erythroid-specific globin gene expression and hemoglobin synthesis. When antisense CP2 was overexpressed in MEL cells, production of endogenous CP2 protein was reduced 70-80%, and significant loss of its promoter binding activity was observed. During HMBA-induced terminal differentiation of antisense CP2 expressing MEL cells, the transcription of endogenous alpha-globin gene was suppressed as expected. Moreover, both beta-globin gene expression and hemoglobin synthesis were also severely impaired, without affecting the expression of key heme enzyme genes or HMBA-induced proliferation and viability., (Copyright 1999 Academic Press.)

Pseudomonas sp. DJ-12 degrades 4-chlorobenzoate through hydrolytic dechlorination to produce 4-hydroxybenzoate and a chloride ion. The fcbB gene encoding the 4-chlorobenzoate-coenzyme A (4CBA-CoA) dehalogenase which catalyzes the nucleophilic substitution reaction to convert 4CBA-CoA to 4-hydroxybenzoate-coenzyme A (4HBA-CoA) in the consecutive steps of dechlorination was cloned from the chromosome of the organism. A nucleotide sequence analysis of the gene showed an open reading frame consisting of 810 nucleotides, which can encode for a polypeptide of molecular mass 30 kDa, containing 269 amino acid residues. A promoter-like sequence (-35 and -10 region) and a putative ribosome-binding sequence were identified. A deduced amino acid sequence of the 4CBA-CoA dehalogenase showed 86%, 50%, and 50% identity with those of corresponding enzymes in the Pseudomonas sp. CBS3, Arthrobacter sp. SU, and Arthrobacter sp. TM1, respectively.

Based on the surmise that a variety of genes might play important roles in embryonic development and tissue differentiation, and that some of them are likely to be expressed in undifferentiated ES cells, we attempted to identify new genes from the ES cell cDNA library. The modified method of expressed sequence tags (ESTs) and the examination of the expression patterns in adult tissues and in vitro differentiated ES cells were utilized in this study. We have isolated and identified several novel cDNA clones with interesting developmental expression pattern. Among the 83 clones randomly chosen, 23 clones (27.7%) have no homology to any sequences in public databases. The rest contain limited or complete sequence homology to the previously reported mammalian genes or ESTs, yet some clones have not been previously identified in the mouse. To examine the expression profile of clones during development and differentiation, sets of slot blots were hybridized with developmental stage specific or tissue specific probes. Out of 40 novel clones tested (21 totally unknown clones and 19 unidentified clones in mouse), most of them were up- or down-regulated as differentiation proceeded, and some clones showed differentiation-stage specific expression profiles. Surprisingly, a majority of genes were also expressed in adult tissues, and some clones even revealed tissue specific expression. These results demonstrate that not only was the strategy we employed in this study quite efficient for screening novel genes, but that the information gained by such studies would also be a useful guide for further analysis of these genes. It also suggests the feasibility of this approach to explore the genomewide network of gene expression during complicated biological processes, such as embryonic development and tissue differentiation.

The phylogenetic relationships among fourteen isolates of benign Theileria spp. infecting cattle, elk and white-tailed deer were studied by nucleotide sequence comparisons of the variable (V4) region (200 nucleotides) of the small subunit ribosomal RNA gene. Included were six Korean bovine, one Japanese bovine, three North American bovine, and four North American cervine isolates. The SSU rRNA gene from each isolate was amplified, cloned, and the V4 region fragment sequenced. Seven different nucleotide sequence patterns were obtained and classified. Type A was identical to T. buffeli SSU rRNA gene sequence (GenBank Accession No. Z15106) and was found in Korean, Japanese, and North American bovine isolates. Type B was found in bovine isolates from Korea, Japan and North America. Type C was found only in the Korean bovine isolate from Chungnam. Type D was found in a Korean and in a North American bovine isolate. Type E was found in a bovine isolate from Cheju Island of Korea and a North American cervine (elk) isolate. Types F and G were found only in North American cervine isolates (both white-tailed deer and elk) and appear to represent a species separate from the bovine isolates. The presence of several sequence types observed in most of the bovine Theileria isolates may indicate mixed species (or subspecies) populations and/or multiple genotypes within a single species.

The cholesteryl ester transfer protein (CETP) is a plasma glycoprotein that transfers neutral lipids between plasma lipoproteins. The distribution of variations in the CETP gene and their influences on lipid levels were investigated among random members of the Korean population (n = 270) whose profiles of environmental factors were known. The frequencies of the major allele at BamHI, EcoNI, TaqIA, TaqIB, New HinfI RFLPs, and the D442G mutation were 0.77, 0.55, 0.84, 0.62, 0.81, and 0.94, in serial order. The significant associations of the BamHI RFLP and the D442G mutation with the plasma high density lipoprotein (HDL) cholesterol levels were observed in this population. Subjects with genotype B2B2 of the BamHI RFLP had significantly lower HDL cholesterol levels than the mean of total subjects. Subjects with D442G mutant allele had a significantly higher HDL cholesterol levels only in males. Analysis of the covariance model (ANOCOVA) showed that allelic variations in the BamHI RFLP and the D442G mutation sites accounted independently for 4.0 and 5.9% of the total inter-individual variation in plasma HDL cholesterol in males (F = 2.29, p = 0.10; F = 3.4, p = 0.03). The effect of the CETP genotype was very high (about 10%), compared to the total effects of sex, body mass index, age, and smoking habit (20%). In conclusion, the genetic variation of the CETP gene is related to the regulation of plasma HDL cholesterol levels and the extent of the effect seems to be different between male and female in the Korean population.

YH439 is a potential drug candidate for the treatment of various hepatic disorders. YH439 and its three metabolites have been identified in rat urine by liquid chromatography-mass spectrometry (LC-MS) and by gas chromatography (GC)-MS. Identification of YH439 and its metabolites was established by comparing their GC retention times and mass spectra with those of the synthesized authentic standards. Both electron impact- and positive chemical ionization MS have been evaluated. The metabolism study was performed in the rat using oral administration of the drug. A major metabolite (YH438) was identified as the N-dealkylation product of YH439. Other identified metabolites were caused by the loss of the methyl thiazolyl amine group (metabolite II) from YH439, the isopropyl hydrogen malonate group (metabolite IV) and the decarboxylated product (metabolite III) of metabolite II.

Pseudomonas sp. P20 is a soil bacterium growing in biphenyl or 4-chlorobiphenyl as the sole carbon and energy source, where the initial catabolism of biphenyl to form benzoate is catalyzed by four enzymes encoded in the pcbABCD gene cluster. The nucleotide sequence of the 2,3-dihydroxybiphenyl dioxygenase gene corresponding to the pcbC gene was determined. The pcbC gene was composed of 921 base pairs with an ATG initiation codon and a TGA termination codon, which can encode a polypeptide of molecular mass 34 kDa containing 306 amino acids. A promoter-like sequence and ribosome-binding sequence were identified upstream of the initiation codon. The deduced amino acid sequence of 2,3-dihydroxybiphenyl dioxygenase exhibited 47% identity with that of corresponding enzyme of Pseudomonas sp. DJ-12, and less than 35% identity with those of other extradiol-type dioxygenases.