Single-cell RNA sequencing-guided fate-mapping toolkit delineates the contribution of yolk sac erythro-myeloid progenitors

Erythro-myeloid progenitors of the yolk sac that originates during early embryo development has been suggested to generate tissue-resident macrophage, mast cell, and even endothelial cell populations from fetal to adult stages. However, the heterogeneity of erythro-myeloid progenitors (EMPs) is not well characterized. Here, we adapt single-cell RNA sequencing to dissect the heterogeneity of EMPs and establish several fate-mapping tools for each EMP subset to trace the contributions of different EMP subsets. We identify two primitive and one definitive EMP subsets from the yolk sac. In addition, we find that primitive EMPs are decoupled from definitive EMPs. Furthermore, we confirm that primitive and definitive EMPs give rise to microglia and other tissue-resident macrophages, respectively. In contrast, only Kit+ Csf1r- primitive EMPs generate endothelial cells transiently during early embryo development. Overall, our results delineate the contribution of yolk sac EMPs more clearly based on the single-cell RNA sequencing (scRNA-seq)-guided fate-mapping toolkit.

[Effect of recombinant human thrombin for hemostasis in liver resection: a randomized controlled phase Ⅲ clinical trial]

Objective: To evaluate the hemostatic efficacy, safety and immunogenicity of recombinant human thrombin in the treatment of liver wounds that still ooze after conventional surgical hemostasis. Methods: A multicenter, stratified randomized, double-blind, placebo-controlled phase Ⅲ trial with a planned enrollment of 510 subjects at 33 centers, with a 2∶1 randomization to the thrombin group versus the placebo group. An interim analysis will be conducted after approximately 70% of the subjects have completed the observation period. The primary efficacy endpoint was the rate of hemostasis within 6 minutes at the point of bleeding that could be evaluated. Safety analysis was performed one month after surgery, and the positive rates of anti-drug antibody (ADA) and neutralizing antibody were evaluated. Results: At the interim analysis, a total of 348 subjects had been randomized and received the study drug (215 were male and 133 were female). They were aged 19-69 (52.9±10.9)years. Among them, 232 were in the thrombin group and 116 were in the placebo group, with balanced and comparable demographics and baseline characteristics between the two groups. The hemostasis rate at 6 minutes was 71.6% (95%CI:65.75%-77.36%) in the thrombin group and 44.0% (95%CI: 34.93%-53.00%) in the placebo group, respectively (P<0.001). No grade≥3 drug-related adverse events and no drug-related deaths were reported from the study.No recombinant human thrombin-induced immunologically-enhanced ADA or immunologically-induced ADA was detected after topical use in subjects. Conclusion: Recombinant human thrombin has shown significant hemostatic efficacy and good safety in controlling bleeding during liver resection surgery, while also demonstrating low immunogenicity characteristics.

Two-Dimensional Terahertz Spectroscopy of Nonlinear Phononics in the Topological Insulator MnBi_{2}Te_{4}

The interaction of a single-cycle terahertz electric field with the topological insulator MnBi_{2}Te_{4} triggers strongly anharmonic lattice dynamics, promoting fully coherent energy transfer between the otherwise noninteracting Raman-active E_{g} and infrared (IR)-active E_{u} phononic modes. Two-dimensional terahertz spectroscopy combined with modeling based on the classical equations of motion and symmetry analysis reveals the multistage process underlying the excitation of the Raman-active E_{g} phonon. In this nonlinear combined photophononic process, the terahertz electric field first prepares a coherent IR-active E_{u} phononic state and subsequently interacts with this state to efficiently excite the E_{g} phonon.

Assertive communication training for nurses to speak up in cases of medical errors: A systematic review and meta-analysis

BACKGROUND

Several authors have previously assessed the effects of assertive communication training for nurses to speak up in cases of medical errors. Inconsistent results regarding the nurses' attitudes, behaviors, and confidence levels were noticed.

OBJECTIVE

To identify the effectiveness of assertive communication training on nurses' behaviors, attitudes, and confidence levels for speaking up in cases of medical errors and to identify vital components for success.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, ERIC, Embase, Scopus, and CINAHL were searched up for studies published from the inception of the database to December 16, 2022.

METHODS

Two researchers independently performed a primary screening of titles and abstracts for relevant studies, followed by a review of full texts if the references met inclusion criteria and quality assessment. Data were retrieved for nurses and nursing students who received medical error-related assertive communication training for speaking up, and learning outcomes for attitudes, behaviors, and confidence levels were reported based on pooled data. Pooled estimates were calculated using a random-effects model.

RESULTS

A total of eleven studies with 1299 participants were included in systematic review, and among them nine studies with 804 participants were analyzed in meta-analysis. From the pooled results, the intervention group, which received assertive communication training, exhibited substantially improved speaking-up behaviors compared with the control group (SMD = 0.58; 95 % CI, 0.14-1.03). Considerable differences were noted in the nurses' times of speaking up in cases of medical errors between pretest (38 %; 95 % CI, 0.14-0.68) and posttest (78 %; 95 %CI, 0.70-0.85) based on the pooled data. The nurses' attitudes and confidence levels for speaking up varied markedly between pretest and posttest.

CONCLUSION

Structured assertive communication training may improve nurses' speaking-up behaviors in cases of medical errors. To conduct effective assertive communication training, nursing educators should incorporate multiple teaching approaches into structured training and ensure an adequate training duration.

Exploration of students' reaction in medical error events and the impact of personalized training on the speaking-up behavior in medical error events

BACKGROUND

The ability of medical students to speak up before a medical error occurs is a timely and necessary interaction to prevent potential patient harm. As it may be crucial to improve patient safety, we explored how medical students react to a medical error and provided them appropriate training regarding speaking up about medical issues.

METHODS

A quasi-experimental study was conducted in Taiwan involving 153 medical students who participated in a speaking-up simulation course. They were divided into two groups. The first group participated in a non-life-threatening scenario before the intervention, followed by a personalized debriefing session, then a life-threatening scenario after the intervention. The second group participated in a life-threatening scenario before the intervention, followed by a personalized debriefing session, then a non-life-threatening scenario after the intervention. Students also completed patient safety attitude survey.

RESULTS

During the preintervention scenario, the overall medical students' speaking-up rate to medical error was 45.1%. The speaking-up rate of medical students in life-threatening scenario was significantly higher than the rate in non-life-threatening scenario before the intervention (64.6% vs 24.3%, p < 0.001). After personalized debriefing, the speaking-up rate to medical errors was significantly improved both in life-threatening scenarios (95.9%, p < 0.001) and in non-life-threatening scenarios (100%, p < 0.001). Male medical students had significantly higher speaking-up rates than female students in life-threatening scenario (76.2% vs 51.4%, p = 0.02). On post-intervention surveys, students provided several reasons for their likelihood of speaking up or remaining silent during a medical error event.

CONCLUSIONS

Medical students' rate of speaking-up to medical error was higher in a simulated life-threatening scenario than in a simulated non-life-threatening scenario. Faculty-led personalized debriefing can facilitate medical students' adoption of communication strategies to speak up more in medical error events. Educators should also consider gender differences when they design effective assertive communication courses.[Box: see text].

Comparison of simulation-based interprofessional education and video-enhanced interprofessional education in improving the learning outcomes of medical and nursing students: A quasi-experimental study

BACKGROUND

Use of interprofessional education has greatly expanded and is widely used to foster interprofessional collaborative practice competency in health professionals, especially during medical emergencies. Identifying the interprofessional education delivery mode that can maximize learning outcomes within available resources is crucial for achieving the sustainability of an interprofessional education program.

OBJECTIVES

To examine the learning outcomes of simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education modules and to analyze the variable costs between these two interprofessional education modules.

DESIGN

A prospective quasi-experimental study.

SETTING

A medical university in Northern Taiwan.

PARTICIPANTS

24 medical students and 48 nursing students enrolled in a 4-week simulation-based interprofessional education or video-enhanced interactive discussion interprofessional education program.

METHODS

Students' medical task performance, critical medical task performance, team behavior performance, and interprofessional collaboration attitude were examined at the pretest and posttest by using an objective structured checklist and team performance rating scale with a hands-on simulation model and structured questionnaires. The variable costs for simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education were estimated upon the completion of the course.

RESULTS

All learning outcomes significantly improved for both the groups from the pretest to posttest. After the intervention, the simulation-based interprofessional education group exhibited significantly higher scores in medical task performance, critical medical task performance and team behavior performance than the video-enhanced interactive discussion interprofessional education group at the posttest. No significant difference was noted in interprofessional collaboration attitude between the groups. Cost analysis revealed that the simulation-based interprofessional education program was approximately two times more expensive in terms of staffing costs and required 1.3 times greater space charges than the video-enhanced interactive discussion interprofessional education program.

CONCLUSION

Both simulation-based interprofessional education and video-enhanced interactive discussion interprofessional education modules effectively improved medical and nursing students' medical task performance, critical medical task performance and team behavior performance. The simulation-based interprofessional education group had more favorable learning outcomes, but the associated costs were higher. Educators should consider both learning outcomes and cost when choosing a design strategy simulation-based interprofessional education vs. video-enhanced interactive discussion interprofessional education for interprofessional education module development.

Comparison of learning outcomes of interprofessional education simulation with traditional single-profession education simulation: a mixed-methods study

BACKGROUND

Interprofessional collaborative practice is essential for meeting patients' needs and improving their health outcomes; thus, the effectiveness of interprofessional education (IPE) should be clearly identified. There is insufficient evidence in the literature to determine the outcomes of IPE compared to traditional single-profession education (SPE). This study aimed to compare the outcomes of IPE and SPE during a simulation training course.

METHODS

The study design was a mixed-methods, incorporated cross-over design and a qualitative survey. A total of 54 students including 18 medical students and 36 nursing students were recruited from March to April 2019. The 4-week simulation course was designed based on Kolb's experimental learning theory and Bandura's social learning theory. Participants were evenly divided into group 1 (received IPE-learning followed by SPE-learning), and group 2 (received SPE-learning followed by IPE-learning). Students' medical task performance, team behavior performance, teamwork attitude, and patient safety attitude were collected at pretest, mid-test, and posttest. Descriptive statistics and repeated measures analysis of variance were used. End-of-study qualitative feedback was collected, and content analysis was performed.

RESULTS

Both groups demonstrated moderate-to-large within-group improvements for multiple learning outcomes at mid-test. Group 1 students' medical task performance (F = 97.25; P < 0.001) and team behavior performance (F = 31.17; P < 0.001) improved significantly. Group 2 students' medical task performance (F = 77.77; P < 0.001), team behavior performance (F = 40.14; P < 0.001), and patient safety attitude (F = 6.82; P < 0.01) improved significantly. Outcome differences between groups were nonsignificant. Qualitative themes identified included: personal factor, professional factor, interprofessional relationship, and learning. The IPE program provided students with exposure to other professions and revealed differences in expertise and responsibilities.

CONCLUSION

IPE-simulation and SPE-simulation were effective interventions that enabled medical and nursing students to develop critical medical management and team behavior performance. IPE-simulation provided more opportunities for improving competencies in interprofessional collaborative practice. In circumstances with limited teaching resources, SPE-simulation can be an acceptable alternative to IPE-simulation.

Factors associated with medical students speaking-up about medical errors: A cross-sectional study

BACKGROUND

Training medical students to speak up when they witness a potential error is an important competency for patient safety, but details regarding the barriers that prevent medical students from effectively communicating are lacking. Therefore, this study aimed at exploring the factors affecting medical students' willingness to speak up for patient safety when a medical error was observed.

METHODS

This is a cross-sectional study at a medical university in Taiwan, and 151 medical students in clinical clerkship completed a survey including demographic characteristics, conflict of interests/social relationship, personal capability, and personality and characteristics of senior staff domains. Data were analyzed using t-test.

RESULTS

Three of five items in the conflict of interests/social relationship domain showed statistically significant importance, including 'I am afraid of being punished' (Mean difference, MD = 0.37; p < 0.01), 'I do not want to break unspoken rules' (MD = 0.55; p < 0.01), and 'I do not want to have bad team relationship' (MD = 0.58; p < 0.01). Two items (perception of knowledge/understanding and communication skills) in the personal capability domain were significantly important to speaking up. Six of 10 items in personality and characteristics of senior staff domain were rated significantly important in deciding to speak up. The top three factors of them were senior personnel with 'Grumpy' personality (MD = 1.20; p < 0.01), 'hierarchy gap' (MD = 1.12; p < 0.01), and senior personnel with 'Stubborn' personality (MD = 1.06; p < 0.01).

CONCLUSION

Our findings demonstrated medical students' perspectives on barriers to speaking up in the event of medical error. Some factors related to characteristics of senior staff could compromise medical students' ability to speak up in the event of medical error. These results might be important for medical educators in designing personalized educational activities related to medical students' ability to speak up for patient safety.

[Cone-beam CT evaluation of the Monson's spherical radius of young adults in Guangdong]

Objective: To measure and analyze the spherical radius of Monson of normal young people in Guangdong province using cone-beam CT (CBCT), and to establish a personalized measurement method of the spherical radius of Monson to provide a reference for clinical application of Monson spherical radius in occlusal reconstruction. Methods: Sixty healthy young adults from physical examination population at Stomatology Hospital of Guangzhou Medical University [30 males and 30 females, aged (22.1±2.0) years 18-26 years) were recruited, and their CBCT were taken. Three-dimensional reconstruction of CBCT data was carried out, and the reconstructed models were fixed, traced and measured. The difference of Monson spherical radius between male and female was compared by using a single sample t-test. Results: The Monson spherical radius was (100.72±4.89) mm. The Monson spherical radius of male and female were (103.48±4.19) mm and (97.97±3.93) mm respectively. The difference between male and female was statistically significant (P<0.01). Conclusions: CBCT can be used to accurately measure the spherical radius of Monson and can be used as a reference for reconstruction of occlusal plane.

Comparison of the effects of simulation training and problem-based scenarios on the improvement of graduating nursing students to speak up about medication errors: A quasi-experimental study

BACKGROUND

Medication administration errors are common among new nurses. Nursing students might be less willing to speak up about errors because of a lack of knowledge and experience.

OBJECTIVES

To examine the effects of simulation training and problem-based scenarios on speaking up about medication errors among graduating nursing students.

DESIGN

Prospective, controlled experimental study design.

SETTING

A university four-year nursing program in Taiwan.

PARTICIPANTS

In total, 93 graduating nursing students in their last semester were recruited. Sixty-six students who received both a problem-based scenario and medication administration simulation training comprised the experimental group, while 27 students who received problem-based scenarios alone comprised the control group.

METHODS

Experimental group students underwent 2 h of simulation training. This training class was designed based on Kolb's experiential learning theory for knowledge development and speaking up about errors. Students in both groups administered medications in problem-based scenarios with eight embedded errors. Students' performance in speaking up about medication errors was directly observed and graded using an objective structured checklist. The McNeamer Chi-squared test, paired t-test, Z test, t-test, and Hedges' g effect size were conducted.

RESULTS

The number of times participants spoke up about medication errors significantly improved in both the experimental group (pre-test: 2.05 ± 1.12 and post-test 6.14 ± 1.25, t = 22.85, p<0.001) and control group (pretest: 2.04 ± 1.16 and post-test: 4.26 ± 1.63, t = 6.33, p<0.001). However, after the intervention, the mean number of times participants spoke up about medication errors in the experimental group was significantly higher than that in the control group (t = 5.99, p<0.001) in the post-test.

CONCLUSIONS

Simulation training exhibited more-significant improvements than problem-based scenarios. Nursing schools and hospitals should incorporate simulation training or at least problem-based scenarios to improve medication safety.

P5990In vivo tracking of long-term survival of xenogeneic porcine mesenchymal stem cells seeded on tissue-engineered heart valve implanted in sheep

Background

Long-term survival of xenogeneic transplanted cells in adults requires strong immunosuppression and/or encapsulation of the cells to achieve peripheral transplant tolerance.

Purpose

The aim of our project was to seed decellularized tissue engineered heart valves (TEHV) with xenogeneic (porcine) mesenchymal stem cells (pMSCs) transfected transiently (Lipofectamine) with a positron emission tomography (PET)-reporter gene (pMSC-PETr), followed by implantation as pulmonary valve replacement into sheep without immunosuppression. The fate of the seeded pMSC-PETr was tracked via serial in-vivo non-invasive PET-computed tomography (PET-CT).

Methods

Static cultivation of TEHV scaffold led to successful ingrowth of the pMSC-PETr. For enabling quantitative assessment of viable pMSC-PETr in the TEHV scaffold after in vivo implantation, vials containing 5x104, 2x105, and 4x105 pMSC-PETr were in vitro mixed with the [18F]-FHBG PET tracer for 1 hr, then the non-bound tracer was washed out and vials were in vitro PET-CT imaged, giving reference values. TEHV-pMSC-PETr were then implanted percutaneously into the pulmonary valve position of sheep (n=4) under general anesthesia, while an additional sheep with no valve implantation served as a control. Ten mCi of [18F]-FHBGPET radiotracer was produced for each procedure and serial PET-CT imaging of the sheep was performed at 3 hr, 24 hr, 2 or 3 weeks, and 5 and 6 months after valve implantation. The study followed the Principles of laboratory animal care.

Results

PET-CT of vials containing increasing number of pMSC-PETr showed dose-dependent tracer uptake in the transfected cells in vitro (Figure). PET-CT images of the sheep 3 hr after implantation of the TEHV-pMSC-PETr showed a clear signal of transfected cells, with a mean estimated number of viable pMSC-PETr of 5.18±1.19x106. No meaningful decrease of the amount of living cells occurred at 24 hr or 2 or 3 weeks. Interestingly, 5- and 6-month follow-up PET-CT images showed clear in vivo and in vitro (after explantation) PET signals of the pMSC-PETr on TEHV, indicating spontaneous stable transfection of the PET reporter plasmid (insertional mutagenesis). Histology confirmed the survival of the pMSC-PETr at 5 and 6-month after xenogeneic transplantation. Merged immunohistochemistry and fluorescence imaging of anti-pig SLA I and anti-sheep MHC I antibodies and PET-reporter gene (HSV1-tk) suggested in vivo inter-species lateral jump gene transfer between pig MSCs and host sheep cells.

Figure 1

Conclusions

This is the first report on serial non-invasive in vivo tracking of long-term survival of xenogeneic pMSCs-PETr seeded on TEHVs and percutaneously implanted into the pulmonary position of sheep. Long-term follow-up revealed spontaneous stable transfection of the plasmid PET-reporter gene, which suggests the risk of insertional mutagenesis induced by the plasmid (transposon), and PET-reporter gene shuttle from xenogeneic pig MSCs to sheep cells.

Acknowledgement/Funding

LifeValve EU project (grant number: 242008)

Helps from flipped classroom in learning suturing skill: The medical students' perspective

BACKGROUND

Today, flipped classroom (FC) has been widely used in medical education. However, the effectiveness of FC remains controversial. The variation may cause by different subjects or different course design. Moreover, those studies did not explain how the association among different domains of learning objective was in FCs. The purpose of this study was to explore the help of learning domains from a FC of suturing skill in year-5 medical students.

DESIGN

This study determined sample size according to statistical power. A minimum number of 77 participants for regression analysis are needed. Therefore, this study enrolled 78 medical students in a 2-hour suturing course, which consisted of pre-class video and in-class instruction. Both simple and mattress suturing were taught. The students received an anonymous survey with questionnaire of Help from Instruction Questionnaire for Clinical Skills (HIQ-CS) after the course. The HIQ-CS was developed by medical education team according to Bloom's taxonomy, and its reliability was favorable (Cronbach's ^l = 0.839). Factor loadings among all items in the HIQ-CS was also favorable (0.790 to 0.849). This study determined consensus of students' perspective by median (Me) and interquartile range (IQR), and tested mediation among different learning domains by regression.

RESULTS

The results showed medical students agreed FC can help them in learning suturing (Me = 4, IQR = 1). The cognitive help (β = .526, p < .001) was completely mediated by psychomotor help (β = .399, p < .001) and affective help (β = .413, p < .001) to overall helps in FC. The affective help (β = .617, p < .001) was partially mediated by psychomotor help to overall helps in FC.

CONCLUSIONS

FC may help students in learning suturing skill in different domains. Our model explains the cognitive help from FC provides an important foundation for the helps of other domains. Although the model should be examined by different curricula and measurements in future, the model of help from instruction in our study provided an innovated concept and framework in medical education.

Protein kinase C -activating isophthalate derivatives mitigate Alzheimer's disease-related cellular alterations

Abnormal protein kinase C (PKC) function contributes to many pathophysiological processes relevant for Alzheimer's disease (AD), such as amyloid precursor protein (APP) processing. Phorbol esters and other PKC activators have been demonstrated to enhance the secretion of soluble APPα (sAPPα), reduce the levels of β-amyloid (Aβ), induce synaptogenesis, and promote neuroprotection. We have previously described isophthalate derivatives as a structurally simple family of PKC activators. Here, we characterised the effects of isophthalate derivatives HMI-1a3 and HMI-1b11 on neuronal viability, neuroinflammatory response, processing of APP and dendritic spine density and morphology in in vitro. HMI-1a3 increased the viability of embryonic primary cortical neurons and decreased the production of the pro-inflammatory mediator TNFα, but not that of nitric oxide, in mouse neuron-BV2 microglia co-cultures upon LPS- and IFN-γ-induced neuroinflammation. Furthermore, both HMI-1a3 and HMI-1b11 increased the levels of sAPPα relative to total sAPP and the ratio of Aβ42/Aβ40 in human SH-SY5Y neuroblastoma cells. Finally, bryostatin-1, but not HMI-1a3, increased the number of mushroom spines in proportion to total spine density in mature mouse hippocampal neuron cultures. These results suggest that the PKC activator HMI-1a3 exerts neuroprotective functions in the in vitro models relevant for AD by reducing the production of TNFα and increasing the secretion of neuroprotective sAPPα.

Using modified information delivery to enhance the traditional pharmacy OSCE program at TMU - a pilot study

BACKGROUND AND OBJECTIVE

Objective Structured Clinical Examination (OSCE) has been used in many areas of healthcare training over the years. However, it constantly needs to be upgraded and enhanced due to technological and teaching changes. We aim at implementing an integrative OSCE method which employs informatics via the virtual patient within the pharmacy education curriculum at Taipei Medical University to enhance the pharmacy students' competence for using and disseminating information and to also improve critical thinking and clinical reasoning.

METHODS

We propose an integrated pharmacy OSCE which uses standardized patients and virtual patients (DxR Clinician). To evaluate this method, we designed four simulated stations and pilot tested with 19 students in the first year of the Master in Clinical Pharmacy program. Three stations were simulated as the inpatient pharmacy: 1) History and lab data collection; 2) Prescription review; 3) Calling physician to discuss potential prescription problems. The fourth was simulated as the patient ward station to provide patient education. A satisfaction questionnaire was administered at the end of the study.

RESULTS

Students rated their ability of 2.84, 2.37, 2.37, and 3.63 of 5 for each of the four stations, with the second and third being the most difficult stations. The method obtained an average rating of 4.32 of 5 for relevance, 4.16 for improving clinical ability, 4.32 for practicality in future healthcare work, and 4.28 for willing to have another similar learning experience.

CONCLUSION

The integration of Virtual Patient in this study reveals that this assessment method is efficient and practical in many aspects. Most importantly, it provides the test taker with a much closer real-life clinical encounter. Although it is in many ways more difficult, it also provides for better "learning from mistakes" opportunities for test-takers.

Association between TXNRD1 polymorphisms and anti-tuberculosis drug-induced hepatotoxicity in a prospective study

Anti-tuberculosis drug-induced hepatotoxicity (ATDH) is a serious adverse reaction to anti-tuberculosis (TB) treatment. Thioredoxin reductase 1 (TXNRD1), encoded by the TXNRD1 gene, is an important enzyme involved in oxidant challenge. TXNRD1 plays a key role in regulating cell growth and transformation, and protects cells against oxidative damage. We investigated the association between TXNRD1 polymorphisms and ATDH susceptibility. In this prospective study, 280 newly diagnosed TB patients were followed-up for 3 months after beginning anti-TB therapy. Tag single-nucleotide polymorphisms (tag-SNPs) of TXNRD1 were selected using Haploview 4.2 based on the HapMap database of the Chinese Han in Beijing (CHB) panel. Genotyping was performed using the MassARRAY platform. Of the 280 patients enrolled in this study, 33 were lost to follow-up, 24 had ATDH, and 223 were free from ATDH. After adjusting for sex, age, smoking status, and body mass index, there were no significant differences in the allele and genotype frequency distributions of TXNRD1 SNPs between the ATDH and non-ATDH groups (all P > 0.05). The haplotype analysis showed that haplotype TCAGCC was associated with an increased risk of ATDH susceptibility [P = 0.024, OR (95%CI) = 6.273 (1.023-38.485)]. Further stratified analyses showed that the haplotype TCAGCC was associated with ATDH susceptibility in female subjects [P = 0.036, OR (95%CI) = 5.711 (0.917-35.560)] and non-smokers [P = 0.029, OR (95%CI) = 6.008 (0.971-37.158)]. Our results suggest that TXNRD1 variants may favor ATDH susceptibility in females and non-smokers. Further studies are required to verify this association.

Thermal conductivity of the diamond-chain compound Cu₃(CO₃)₂(OH)₂

Thermal conductivity (κ) of a distorted spin diamond-chain system, Cu3(CO3)2(OH)2, is studied at low temperatures down to 0.3 K and in magnetic fields up to 14 T. In zero field, the κ(T) curve with heat current along the chain direction has very small magnitudes and shows a pronounced three-peak structure. The magnetic fields along and perpendicular to the chains change the κ strongly in a way having good correspondence to the changes of magnetic specific heat in fields. The data analysis based on the Debye model for phononic thermal conductivity indicates that the heat transport is due to phonons and the three-peak structure is caused by two resonant scattering processes by the magnetic excitations. In particular, the spin excitations of the chain subsystem are strongly scattering phonons rather than transporting heat.

Control of Immune Response to Allogeneic Embryonic Stem Cells by CD3 Antibody-Mediated Operational Tolerance Induction

Implantation of embryonic stem cells (ESCs) and their differentiated derivatives into allogeneic hosts triggers an immune response that represents a hurdle to clinical application. We established in autoimmunity and in transplantation that CD3 antibody therapy induces a state of immune tolerance. Promising results have been obtained with CD3 antibodies in the clinic. In this study, we tested whether this strategy can prolong the survival of undifferentiated ESCs and their differentiated derivatives in histoincompatible hosts. Recipients of either mouse ESC-derived embryoid bodies (EBs) or cardiac progenitors received a single short tolerogenic regimen of CD3 antibody. In immunocompetent mice, allogeneic EBs and cardiac progenitors were rejected within 20-25 days. Recipients treated with CD3 antibody showed long-term survival of implanted cardiac progenitors or EBs. In due course, EBs became teratomas, the growth of which was self-limited. Regulatory CD4(+)FoxP3(+) T cells and signaling through the PD1/PDL1 pathway played key roles in the CD3 antibody therapeutic effect. Gene profiling emphasized the importance of TGF-β and the inhibitory T cell coreceptor Tim3 to the observed effect. These results demonstrate that CD3 antibody administered alone promotes prolonged survival of allogeneic ESC derivatives and thus could prove useful for enhancing cell engraftment in the absence of chronic immunosuppression.

Phytoremediation of soils contaminated with phenanthrene and cadmium by growing willow (Salix × aureo-pendula CL 'j1011')

To assess the phytoremediation potential of an autochthonous willow (Salix × aureo-pendula CL 'J1011') for phenanthrene (PHE)-contaminated soils and PHE-cadmium (PHE-Cd) co-contaminated soils, we conducted field experiments in the lower reaches of the Yangtze River, China. Ethylenediaminetetraacetic acid (EDTA) and ethyl lactate were tested for individual and combined effects on the phytoremediation efficiency. For PHE-contaminated soils, willow plus ethyl lactate resulted in significant removal of PHE from soils after 45 days, and the PHE concentration in the shoots was significantly higher with than without ethyl lactate. For PHE-Cd co-contaminated soils, both willow plus EDTA and willow plus EDTA and ethyl lactate led to a significant decrease in the concentrations of PHE and Cd in the soils after 45 days, whereas willow alone did not. The PHE and Cd concentrations in the willow shoots were significantly enhanced in the presence of EDTA alone and with ethyl lactate, except for the PHE concentration in stems with EDTA alone. Under the same treatment, the presence of Cd had no significant influence on the PHE removal from soils. The results indicate the feasibility of using this willow together with both EDTA and ethyl lactate for the simultaneous removal of PHE and Cd from soils.

Characteristics of Small Intestinal Diseases on Single-Balloon Enteroscopy: A Single-Center Study Conducted Over 6 Years in China

The small intestine has been considered inaccessible for a long term. The development of single-balloon endoscopy has greatly improved the diagnosis and treatment possibilities for small intestinal diseases.In this study, we aimed to explore the demographic characteristics and small intestinal diseases of patients who underwent single-balloon enteroscopy between 2009 and 2014 at our endoscopy center. We determined the enteroscopic findings for each small intestinal disease and the most susceptible age groups.In total, 186 patients were included in the study. Their mean age was 45.87 ± 15.77 years. Patients who underwent single-balloon enteroscopy were found to have neoplasms (most common age group: 14-45 years, most common lesion location: jejunum), lymphoma (46-59 and 60-74 years, ileum), protuberant lesions (45-59 years, jejunum), inflammation (14-45 and 46-59 years, ileum), benign ulcers (14-45 years, jejunum), diverticulum (14-45 years, ileum), vascular malformations (60-74 years, jejunum), polyps (14-45 years, jejunum), Crohn's disease (14-45 years, jejunum), hookworm infection (14-45 years, jejunum), lipid pigmentation (14-45 and 46-59 years, jejunum), undetermined bleeding (46-59 years, ileum), or undetermined stenosis (31 years, duodenum). Each small intestinal disease had distinct enteroscopic findings.

Electrical stimulation therapy of the lower oesophageal sphincter for refractory gastro-oesophageal reflux disease - interim results of an international multicentre trial

BACKGROUND

A previous single-centre study showed that lower oesophageal sphincter electrical stimulation therapy (LES-EST) in gastro-oesophageal reflux disease (GERD) patients improves reflux symptoms and decreases oesophageal acid exposure.

AIM

To evaluate safety and efficacy of LES-EST in GERD patients with incomplete response to proton pump inhibitors (PPIs) in a prospective, international, multicentre, open-label study.

METHODS

GERD patients, partially responsive to PPIs, received LES-EST. GERD health-related quality of life (GERD-HRQL), daily symptom diaries, quality of life scores, oesophageal acid exposure, and LES resting and residual pressure were measured before and after initiation of LES-EST. Stimulation sessions were optimised based on residual symptoms and oesophageal acid exposure.

RESULTS

Forty-four patients were enrolled and 6-month data from 41 patients are available. Hiatal repair was performed in 16 patients. One device-related, one procedure-related and one unrelated severe adverse event were reported. GERD-HRQL improved from 31.0 (IQR 26.2-36.8) off-PPI and 16.5 (IQR 9.0-22.8) on-PPI to 4 (IQR 1-8) at 3-month and 5 (IQR 3-9) at 6-month follow-up (P < 0.0001 vs. on- and off-PPI). Oesophageal acid exposure (pH < 4.0) improved from 10.0% (IQR 7.5-12.9) to 3.8% (IQR 1.9-12.3) at 3 months (P = 0.0027) and 4.4% (IQR 2.2-7.2) at 6 months (P < 0.0001).

CONCLUSIONS

These interim results show an acceptable safety record of LES-EST to date, combined with good short-term efficacy in GERD patients who are partially responsive to PPI therapy. A remarkable reduction in regurgitation symptoms, without the risk of intervention-requiring dysphagia may prove to be an advantage compared with other anti-reflux procedures. ClinicalTrials.gov Identifier: NCT01574339.

Peripheral blood-derived mesenchymal stem cells: candidate cells responsible for healing critical-sized calvarial bone defects

Postnatal tissue-specific stem/progenitor cells hold great promise to enhance repair of damaged tissues. Many of these cells are retrieved from bone marrow or adipose tissue via invasive procedures. Peripheral blood is an ideal alternative source for the stem/progenitor cells because of its ease of retrieval. We present a coculture system that routinely produces a group of cells from adult peripheral blood. Treatment with these cells enhanced healing of critical-size bone defects in the mouse calvarium, a proof of principle that peripheral blood-derived cells can be used to heal bone defects. From these cells, we isolated a subset of CD45(-) cells with a fibroblastic morphology. The CD45(-) cells were responsible for most of the differentiation-induced calcification activity and were most likely responsible for the enhanced healing process. These CD45(-) fibroblastic cells are plastic-adherent and exhibit a surface marker profile negative for CD34, CD19, CD11b, lineage, and c-kit and positive for stem cell antigen 1, CD73, CD44, CD90.1, CD29, CD105, CD106, and CD140α. Furthermore, these cells exhibited osteogenesis, chondrogenesis, and adipogenesis capabilities. The CD45(-) fibroblastic cells are the first peripheral blood-derived cells that fulfill the criteria of mesenchymal stem cells as defined by the International Society for Cellular Therapy. We have named these cells "blood-derived mesenchymal stem cells."

CD34+ stem cell therapy in nonischemic dilated cardiomyopathy patients

Recent trends indicate that patients with nonischemic dilated cardiomyopathy represent the largest subpopulation of heart failure patients with a significant need for alternative treatment modalities. Similar to patients with ischemic cardiomyopathy, patients with nonischemic dilated cardiomyopathy have been found to have myocardial regions with flow abnormalities, which may represent targets for neoangiogenic therapies. CD34(+) stem cells might contribute to the formation of new blood vessels from existing vascular structures in ischemic tissues by the direct incorporation of injected cells into the newly developing vasculature or by the production and secretion of angiogenic cytokines. This review summarizes the long-term clinical effects and potential underlying mechanisms of CD34(+) cell therapy in patients with nonischemic dilated cardiomyopathy.

Antitopoisomerase antibody positivity predates nailfold capillaroscopy abnormalities in scleroderma. Postulated classification of 'prescleroderma'

In a patient with early topoisomerase antibody-positive scleroderma, antinuclear antibody positivity was fortuitously observed to predate nailfold capillaroscopy changes. Using this case as a template, the prediagnostic phase of the presumed multifactorial disease may be divided into 5 temporal phases--phase 1 representing conception and intrauterine environment, phase 2 representing the extrauterine environment predating environmental exposure; phase 3 representing the early post-environmental exposure interval with no detectable perturbed body status; phase 4 representing the post-environmental exposure interval characterized by autoantibody production and microvascular changes, and phase 5, the symptomatic clinical prediagnostic interval (Raynaud's, skin, musculoskeletal, gastrointestinal, cardiorespiratory) prompting scleroderma diagnosis. Temporal classification of prescleroderma aids in both the understanding and definition of scleroderma 'onset'. If altered nailfold capillaries and autoantibodies develop at comparable rates, and if the findings from this case--that autoantibody changes precede microvascular changes--are truly representative of the preclinical disease phase, then these findings argue that the evolution of the disease is from within the vessel outwards, rather than vice versa.

Evaluation for the ecological quality status of coastal waters in East China Sea using fuzzy integrated assessment method

This research presented an evaluation for the ecological quality status (EcoQS) of three semi-enclosed coastal areas using fuzzy integrated assessment method (FIAM). With this method, the hierarchy structure was clarified by an index system of 11 indicators selected from biotic elements and physicochemical elements, and the weight vector of index system was calculated with Delphi-Analytic Hierarchy Process (AHP) procedure. Then, the FIAM was used to achieve an EcoQS assessment. As a result of assessment, most of the sampling stations demonstrated a clear gradient in EcoQS, ranging from high to poor status. Among the four statuses, high and good, owning a ratio of 55.9% and 26.5%, respectively, were two dominant statuses for three bays, especially for Sansha Bay and Luoyuan Bay. The assessment results were found consistent with the pressure information and parameters obtained at most stations. In addition, the sources of uncertainty in classification of EcoQS were also discussed.

Association of two glyoxalase I gene polymorphisms with nephropathy and retinopathy in Type 2 diabetes

BACKGROUND

Glyoxalase I (GLO1), which is the major enzyme that catalyzes the metabolism of methylglyoxal (MG), may play an important role in the pathogenesis of diabetic microvascular complications.

AIM

To investigate whether the C-7T and A419C polymorphisms of the GLO1 gene are associated with nephropathy and retinopathy in Chinese Type 2 diabetic patients.

SUBJECTS AND METHODS

A total of 364 Type 2 diabetic patients and 301 healthy controls were enroled in the study. Diabetic microvascular complications were determined by urinary albumin excretion measurements and ophthalmological examinations. Genetic analyses were performed using either Taqman PCR or direct sequencing. The effect of C-7T polymorphism on promoter activity was measured by reporter gene assays.

RESULTS

The albumin/ creatinine ratio (ACR) and prevalence of nephropathy and retinopathy were significantly higher in diabetic patients with GLO1 -7CC genotype than in patients with -7CT and -7TT genotypes (p=0.02, p=0.02, and p=0.04, respectively). The - 7CC genotype is independently associated with ACR (β=0.13, p=0.01) and the risk for retinopathy [odds ratio (OR): 2.30, 95% confidence interval (CI): 1.25-4.24, p<0.01]. The luciferase activity of the -7T promoter was higher than that of the -7C promoter (13.2±0.2 vs 11.7±0.8, p=0.04). No differences were found between ACR and the prevalence of nephropathy and retinopathy for A419C polymorphism in Type 2 diabetic patients.

CONCLUSIONS

GLO1 C-7T polymorphism alters promoter activity and confers susceptibility to nephropathy and retinopathy to Type 2 diabetic patients.

Indirect imaging of cardiac-specific transgene expression using a bidirectional two-step transcriptional amplification strategy

Transcriptional targeting for cardiac gene therapy is limited by the relatively weak activity of most cardiac-specific promoters. We have developed a bidirectional plasmid vector, which uses a two-step transcriptional amplification (TSTA) strategy to enhance the expression of two optical reporter genes, firefly luciferase (fluc) and Renilla luciferase (hrluc), driven by the cardiac troponin T (cTnT) promoter. The vector was characterized in vitro and in living mice using luminometry and bioluminescence imaging to assess its ability to mediate strong, correlated reporter gene expression in a cardiac cell line and the myocardium, while minimizing expression in non-cardiac cell lines and the liver. In vitro, the TSTA system significantly enhanced cTnT-mediated reporter gene expression with moderate preservation of cardiac specificity. After intramyocardial and hydrodynamic tail vein delivery of an hrluc-enhanced variant of the vector, long-term fluc expression was observed in the heart, but not in the liver. In both the cardiac cell line and the myocardium, fluc expression correlated well with hrluc expression. These results show the vector's ability to effectively amplify and couple transgene expression in a cardiac-specific manner. Further replacement of either reporter gene with a therapeutic gene should allow non-invasive imaging of targeted gene therapy in living subjects.

Temperature dependent pinning phenomenon in superconducting Nb films with triangular and honeycomb pinning arrays

The pinning phenomena in superconducting Nb films with triangular and honeycomb pinning arrays were explored. Special temperature dependent phenomena were found for both films. For the film with a triangular pinning array, the pronounced matching peaks in the critical currents as a function of magnetic field reduce from six to three within a narrow temperature range. This temperature dependent matching effect is explained by considering the dramatic change of coherent length with temperature when the temperature is close to T(c). In order to compare with the film with a triangular pinning array, we fabricated a film with a honeycomb pinning array with similar pinning site spacing and pinning size. Special prominent matching peaks at H = 3.5H(1) were found for this film. Molecular dynamic simulations were made to study this phenomenon. The ground state distribution of vortices obtained from simulations reasonably explains the prominent matching peaks. Pronounced temperature dependent matching effects were also found for the film with a honeycomb pinning array.

Zinc is the metal cofactor of Borrelia burgdorferi peptide deformylase

Peptide deformylase (PDF, E.C. 3.5.1.88) catalyzes the removal of N-terminal formyl groups from nascent ribosome-synthesized polypeptides. PDF contains a catalytically essential divalent metal ion, which is tetrahedrally coordinated by three protein ligands (His, His, and Cys) and a water molecule. Previous studies revealed that the metal cofactor is a Fe2+ ion in Escherichia coli and many other bacterial PDFs. In this work, we found that PDFs from two iron-deficient bacteria, Borrelia burgdorferi and Lactobacillus plantarum, are stable and highly active under aerobic conditions. The native B. burgdorferi PDF (BbPDF) was purified 1200-fold and metal analysis revealed that it contains approximately 1.1 Zn2+ ion/polypeptide but no iron. Our studies suggest that PDF utilizes different metal ions in different organisms. These data have important implications in designing PDF inhibitors and should help address some of the unresolved issues regarding PDF structure and catalytic function.

Thermostability of Cromobacterium viscosum lipase in AOT/isooctane reverse micelle

The thermostability of Cromobacterium viscosum lipase (EC 3.1.1.3) entrapped in AOT (sodium bis-[2-ethylhexyl] sulfosuccinate) reverse micelles was increased by the addition of short-chain polyethylene glycol (PEG 400). Two different approaches were considered: (1) the determination of half-life time and (2) the mechanistic analysis of deactivation kinetics. The half-life of lipase entrapped in AOT/isooctane reverse micelles with PEG 400 at 60 degrees C was 28 h, ninefold higher than that in reverse micelles without PEG 400. The lipase entrapped in both reverse micellar systems followed a series-type deactivation mechanism involving two first-order steps. The deactivation constant for the first step at 60 degrees C in PEG containing reverse micelles was 0.055 h!1, 11-fold lower than that in reverse micelles without PEG, whereas it remained almost constant for the second step. The inactivation energy of the lipase entrapped in reverse micelles with and without PEG 400 was 88.12 and 21.97 kJ/mol, respectively.

Trans-cutaneous electrogastrographic study of gastric myoelectric activity in transposed intrathoracic stomach after esophagectomy

We examined the feasibility of trans-cutaneous electrogastrography (EGG) in recording myoelectric activity of the transposed thoracic stomach after esophagectomy. Nineteen patients who had Ivor-Lewis esophagectomy were studied. The EGG signal was recorded using cutaneous electrodes placed over the lower sternum. Eleven patients who underwent total gastrectomy served as controls. Normal rhythm pattern (2.4-3.6 cpm > or = 70%) and power ratio (PR > or = 2) was observed in five and 12 patients, respectively, after esophagectomy. The observation of normal gastric rhythm was more frequent in the postprandial period in the esophagectomy group (median 42.6%vs. 7.4%, P = 0.01), and the PR was significantly higher (median 2.27 vs. 1.38, P = 0.013) than the gastrectomy group. Feeding further increased the prevalence of normal gastric slow wave in the esophagectomy group (median 14.8% to 42.6%, P = 0.002) and improved the stability of dominant frequency (median 78% to 67%, P = 0.015). We conclude that gastric myoelectric activities of thoracic transposed stomach can be detected from cutaneous sternal electrodes. This represented a preservation of gastric motility even when the stomach is pulled up to the thorax as a substitute for the esophagus.

Functional and clinical significance of hepatitis D virus genotype II infection

Hepatitis D virus (HDV) infection is one of the important etiologies of fulminant hepatitis and may aggravate the clinical course of chronic HBV infection to cirrhosis and liver failure. HDV was classified into three genotypes. Recent molecular phylogenetic analysis of HDV suggests at least seven major clades. The genotype I HDV is widely spread, genotype II is found in East Asia and genotype III HDV is prevalent in South America. The genomic size is 1682-1685 nucleotides (nt) for genotype II, and 1676 nt for genotype IV (IIb). The divergence in HDV nucleic acid sequences between genotype II and other genotypes varies from 13.8% to 35.3%. The divergences in the HDAg-coding region may range from 17.8% to 29.8% between genotype II and other genotypes. There is no genotypic or size restriction on the interactions of either the small or the large hepatitis delta antigens (HDAgs) between genotypes I and II, and there is also no genotypic incompatibility during co-package of HDAgs of different genotypes into virus like particles. There appears no apparent universal genotypic restriction of the transactivation of genotype I HDV RNA replication by small HDAg of genotype II. In contrast, there appears more genotypic restriction for genotype I small HDAgs to transactivate genotype II HDV RNA replication. Of the functional domains of HDAg, the 19 amino acids at the carboxyl-end of the large HDAg show the greatest divergences (70%-80%) between genotypes I and II. The viral packaging efficiencies of genotype I HDV isolates are usually higher than those of genotype II. The 19 amino acids at the carboxyl-end seem to be the most important determinant for viral packaging efficiencies. The editing efficiencies of the genotype I HDV are also higher than those of the genotype II. Genotype II HDV infection is relatively less frequently associated with fulminant hepatitis at the acute stage and less unfavorable outcomes [cirrhosis or hepatocellular carcinoma (HCC)] at the chronic stage as compared to genotype I. It appears that the clinical manifestations and outcomes of patients with genotype IV (IIb) HDV infection are more like those of patients with genotype II HDV infection. Persistent replication of HBV or HDV was associated with higher adverse outcomes (cirrhosis, HCC or mortality) compared to those who cleared both viruses from the sera. HBV of the genotype C is also a significant factor associated with adverse outcomes (cirrhosis, HCC or mortality) in patients with chronic hepatitis D in addition to genotype I HDV and age. However, most patients with chronic HDV infection have low or undetectable hepatitis B virus DNA levels. During longitudinal follow-up, genotype I HDV is the most important determinant associated with survival.

Responses of the antioxidant defenses of the Goldfish Carassius auratus, exposed to 2,4-dichlorophenol

Goldfish Carassius auratus were exposed to 0.1mg/l of 2,4-dichlorophenol (2,4-DCP), widely used as transportation power in China, for 2, 5, 10, 20 and 40 days, while one control group was designated for each exposure group. Antioxidant defenses consisting of contents of reduced glutathione (GSH) and glutathione disulfide (GSSG) and activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), selenium-dependent glutathione peroxidase (Se-GPx) and glutathione S-transferase (GST) in liver of freshwater fish were determined and the GSH-GSSG ratio and content of tGSH (total glutathione) were calculated. In the present study, the role of hepatic antioxidant defenses was evaluated and the possible poisoning mechanism of fish can be explained as an oxidative stress mechanism. In addition, hepatic SOD and GSH, especially tGSH, were sensitive to 2,4-DCP contamination and thus, can possibly be used in early assessment of 2,4-DCP-dominant polluted aquatic ecosystems.

Improvement in enzyme activity and stability by addition of low molecular weight polyethylene glycol to sodium bis(2-ethyl-L-hexyl)sulfosuccinate/isooctane reverse micellar system

The activity and stability of Chromobacterium viscosum lipase (glycerolester hydrolase, EC 3.1.1.3)-catalyzed olive oil hydrolysis in sodium bis (2-ethyl-l-hexyl)sulfosuccinate (AOT)/isooctane reverse micelles is increased appreciably when low molecular weight polyethylene glycol (PEG 400) is added to the reverse micelles. To understand the effect of PEG 400 on the phase behavior of the reverse micellar system, the phase diagram of AOT/ PEG 400/water/isooctane system was studied. The influences of relevant parameters on the catalytic activity in AOT/PEG 400 reverse micelles were investigated and compared with the results in the simple AOT reverse micelles. In the presence of PEG 400, the linear decreasing trend of the lipase activity with AOT concentration, which is observed in the simple AOT reverse micelles, disappeared. Enzyme entrapped in AOT/PEG reverse micelles was very stable, retaining >75% of its initial activity after 60 d, whereas the half-life in simple AOT reverse micelles was 38 d. The kinetics parameter maximum velocity (Vmax) exhibiting the temperature dependence and the activation energy obtained by Arrhenius plot was suppressed significantly by the addition of PEG 400.

Effects of water-soluble fractions of diesel oil on the antioxidant defenses of the goldfish, Carassius auratus

Larval goldfish Carassius auratus were exposed to 0.05 and 0.1 mg/L No. 20 diesel oil, widely used as transportation power in China, for 2, 4, 7, 10, 15, 25, and 40 days, while one control group was designated for each exposure group. Some fish after 25 days of exposure were transferred to diluted water until the 40th day. Hepatic antioxidant defense parameters of fish, including contents of reduced glutathione and glutathione disulfide and activities of superoxide dismutase, catalase, glutathione reductase, selenium-dependent glutathione peroxidase, and glutathione S-transferase, were determined and compared to control values. All the results indicated that the antioxidant responses of the fish to the two concentrations of oil exposure were similar on the whole. The possible defense mechanisms of fish and prospective early biomarkers for the evaluation of an oil-dominant contaminated aquatic ecosystem are discussed. In addition, after fish were removed from oil exposure, the recovery status of these antioxidant indices was explored.

Persistent retention of acetic acid is associated with complete tumour necrosis in patients with hepatocellular carcinoma undergoing percutaneous acetic acid injection

BACKGROUND

Ultrasound (US)-guided percutaneous acetic acid injection therapy (PAIT) is effective for patients with hepatocellular carcinoma (HCC). This study aimed to determine the occurrence and predictive value of persistent intra-tumoral retention of acetic acid after PAIT.

METHODS

We prospectively studied 60 (52 M, mean age 68 +/- 10 years) patients with 72 HCC nodules (45 < or = 3 cm) treated with PAIT. The presence of post-treatment persistent retention of acetic acid, defined as a homogeneous and highly hyperechoid mass in US appearance 3 days after completion of the treatment, was correlated with the treatment response.

RESULTS

The mean size of the treated tumour was 2.9 +/- 1.0 cm (range 1.5-5 cm). Thirty (42%) HCC nodules showed complete tumour necrosis demonstrated by contrast-enhanced dynamic CT. Complete response was found in 22 (69%) of 32 nodules showing persistent intra-tumoral retention of acetic acid (P < 0.001). Small (< or = 3 cm) tumour size was also significantly associated with complete tumour necrosis (P = 0.001). There were no significant differences of the injection volume and treatment sessions between those with and without complete tumour necrosis in either small or large (> 3 cm) HCC (P > 0.1). Multivariate logistic regression analysis showed that persistent retention of acetic acid (odds ratio (OR) 10.4, 95% confidence interval (CI) 3.1-34.7; P < 0.001) and tumour size < or = 3 cm (OR 6.8, 95%, CI 1.8-25.8; P = 0.002) were independent factors predicting complete tumour necrosis.

CONCLUSIONS

The presence of persistent retention of acetic acid is associated with a favourable response and may predict complete tumour necrosis after PAIT.

Reliability of contemporary radiology to measure tumour size of hepatocellular carcinoma in patients undergoing resection: limitations and clinical implications

BACKGROUND

Preoperative radiology has been widely used to detect and measure hepatocellular carcinoma (HCC). However, its accuracy and reliability are unclear. This study aimed to assess the ability of current radiology to measure tumour size in patients undergoing resection.

METHODS

We evaluated 212 HCC patients undergoing curative resection. Tumour size measured in the pathological examination was correlated with that obtained in preoperative ultrasound (US) and contrast-enhanced dynamic computed tomography (CT). Accuracy and association with tumour recurrence were investigated.

RESULTS

The mean size of the tumour was 4.5 +/- 2.6 cm and was accurate in both US and CT in only 6 (3%) patients. Cirrhosis (P = 0.015), absence of tumour stain (P = 0.002) and small (< or = 4 cm) tumour (P < 0.001) were the significant factors associated with size deviation using both US and CT. Ninety-four (44%) patients developed tumour recurrence within 17 +/- 11 months of resection. Recurrence rate was 52%, 52% and 67% in patients with underestimation in US (relative risk [RR]: 2.0, 95% confidence interval [CI]: 1.2-3.4, P = 0.01), CT (RR: 2.1, 95% CI: 1.1-4, P = 0.022) and both modalities (RR: 2.5, 95% CI: 1.4-4.2, P = 0.001), respectively, compared to 30% recurrence in patients with accurate estimation of tumour size.

CONCLUSION

The accuracy of radiology in measuring tumour size was poor, and may lead to inappropriate treatment. The finding that underestimation of tumour size was associated with a higher tumour recurrence rate is consistent with the hypothesis that HCC may recur from pre-existing tumour foci which could not be identified from the current imaging modalities.

Comparison of percutaneous acetic acid injection and percutaneous ethanol injection for hepatocellular carcinoma in cirrhotic patients: a prospective study

BACKGROUND

Ultrasound-guided percutaneous ethanol injection (PEI) and percutaneous acetic acid injection (PAI) are effective in the treatment of hepatocellular carcinoma (HCC). We conducted a prospective study to compare the therapeutic efficacy of both these methods.

METHODS

Sixty-three patients were treated by PAI using 50% acetic acid and 62 by PEI using pure ethanol. There were no significant baseline differences in age, sex, Child-Pugh class, tumour size and number, or other clinico-biochemical parameters between the two groups.

RESULTS

During a follow-up period of 24 +/- 9 (range 6-38) months, 19 (30%) of the PAI group and 21 (34%) of the PEI group died (P = 0.704). The 1- and 3-year survival rates were 84% and 51% for the PAI group and 81% and 46% for the PEI group (P = 0.651). The corresponding tumour recurrence rates were 51% and 74% for the PAI group, and 54% and 64% for the PEI group (P = 0.787). The treatment sessions were 3.9 +/- 1.6 and 6.2 +/- 2.3 for the PAI and PEI groups, respectively, in each treatment cycle (P = 0.008). A multivariate analysis using the Cox regression model revealed that ascites (relative risk (RR) 3.1, 95% confidence interval (CI) 1.5-6.3, P = 0.002), large (>3 cm) or multinodular HCCs (RR 2.4, 95% CI 1.1-5.4, P = 0.04), and development of tumour recurrence (RR 7.0, 95% CI 3.1-16.0, P < 0.001) were independent, poor prognostic factors in both groups.

CONCLUSIONS

PAI and PEI are equally effective in the treatment of HCC. PAI has the advantage of fewer treatment sessions in each treatment course. Careful pretreatment patient selection may improve survival.

D1 receptor alleles predict PET metabolic correlates of clinical response to clozapine

A goal of pharmacogenetics is to clarify associations between allelic variation and risk factors in psychiatric illness. We report changes in regional brain metabolism based on dopamine alleles. Treatment-resistant schizophrenic subjects were positron emission tomography scanned with 18F-fluorodeoxyglucose after 5 weeks each of placebo and clozapine treatment. Significant regional brain metabolic effects were found for the D1 receptor genotypes (P < 0.05), adjusted for multiple comparisons. Metabolic decreases for the 2,2 genotype but not the 1,2 genotype were observed in all major sectors of the brain, with the exception of the ventral parts of the caudate and putamen. Frontal, temporal, parietal, and occipital neocortices showed decreased metabolism as did the cingulate juxta-allocortex and the parahippocampal allocortex. Decreases were also observed in the thalamus, amygdala, and cerebellum bilaterally. No significant metabolic differences by genotype were observed for D3, 5HT(2A), and 5HT(2C) polymorphisms. In terms of clinical response, the DRD1 2,2 genotype significantly improved with clozapine treatment, demonstrating a 30% decrease in the Brief Psychiatric Rating Scale positive symptoms in contrast to a 7% worsening for the 1,2 genotype (P < 0.05). In this preliminary study, brain metabolic and clinical response to clozapine are related to the D1 receptor genotype.

Hepatitis C viral genotype influences the clinical outcome of patients with acute posttransfusion hepatitis C

Most patients with an acute infection of hepatitis C virus (HCV) will develop chronic hepatitis, and only about 15-20% of the cases will resolve spontaneously. The mechanism for the different outcomes in patients with acute HCV infection remains unclear. HCV genotype has been recognized as an important factor affecting the clinical course and outcome of chronic hepatitis C patients. In order to evaluate the role of HCV genotype in the clinical course and outcome of acute posttransfusion hepatitis C, 67 patients with acute posttransfusion hepatitis C from a prospective study of posttransfusion non-A, non-B hepatitis were enrolled. Thirty-nine patients (58.2%) were HCV genotype 1b. Among the 67 patients with acute posttransfusion hepatitis C, 53 (79.1%) progressed to chronic hepatitis. Significantly more patients with genotype 1b than non-1b genotypes developed chronic hepatitis (89.7% vs. 64.3%; P = 0.019). There was no significant difference in gender, mean age, amount of transfused blood, hepatitis symptoms, jaundice, incubation period, peak serum alanine transaminase, or serum HCV RNA titer between patients with HCV genotype 1b and non-1b infections. Patients who developed chronic hepatitis had a significantly greater incidence of genotype 1b infection (66.0% vs. 28.6%; P = 0.013) and a longer incubation period (7.3 weeks vs. 5.4 weeks; P = 0.052) than patients whose infection was resolved. Patients with a genotype 1b infection that resolved itself spontaneously all had an incubation period of less than 6 weeks. Multivariate logistic regression analysis revealed that genotype 1b and an incubation period > or = 6 weeks were significant predictive factors for the development of chronic hepatitis. Therefore, the HCV genotype can influence the outcome of patients with acute HCV infection.

Dysfunction of oesophageal motility in Helicobacter pylori-infected patients with reflux oesophagitis

BACKGROUND

Helicobacter pylori infection has been suggested to be protective against gastro-oesophageal reflux disease. However, a significant proportion of patients with gastro-oesophageal reflux disease are infected by H. pylori.

AIM

To study oesophageal motor function in H. pylori-infected patients with reflux oesophagitis.

METHODS

Patients with erosive reflux oesophagitis were recruited prospectively for stationary oesophageal manometry and 24-h ambulatory oesophageal pH monitoring. H. pylori status was determined by biopsy urease test. Non-reflux volunteers were recruited as controls.

RESULTS

Seventy-four patients with erosive oesophagitis (34 H. pylori-positive, 40 H. pylori-negative) and 48 non-reflux patient controls (22 H. pylori-positive, 26 H. pylori-negative) were recruited. There was no difference in severity of oesophagitis (median grade, 1; P=0.53) or oesophageal acid exposure (total percentage time oesophageal pH < 4, 7.6% vs. 6.8%; P=0.57) between H. pylori-positive and H. pylori-negative groups. Compared to H. pylori-negative patients, H. pylori-positive patients had significantly lower basal lower oesophageal sphincter pressure (12.2 mmHg vs. 15.3 mmHg; P=0.03) and amplitude of distal peristalsis (56.9 mmHg vs. 68.4 mmHg; P=0.03). Ineffective oesophageal motility (14% vs. 7%; P=0.02) and failed oesophageal peristalsis were also significantly more prevalent in H. pylori-positive patients.

CONCLUSIONS

Among patients with a similar degree of reflux oesophagitis, H. pylori-infected patients have more severe oesophageal dysmotility and lower oesophageal sphincter dysfunction. Oesophageal motor dysfunction probably plays a dominant role in the development of gastro-oesophageal reflux disease in patients with H. pylori infection.

The spatial distribution of macular pigment in humans

PURPOSE

To estimate the distributions in width as well as in density of macular pigment (MP) in humans at different ages, imaging fundus reflectometry was employed as a tool to reach our aim.

METHODS

Imaging fundus reflectometry was used to measure the macular pigment distribution in human eyes with a modified fundus camera to which a cooled CCD camera was attached. The fundus images were taken at 460 nm and 560 nm after the retina was light-adapted to completely bleach rhodopsin. The density of macular pigment was estimated using a model described in the text. The variation in density with retinal eccentricity was fit to Gaussian distribution. The width of MP in retinal eccentricity was estimated by 95% covering area of the distribution profile. A total of 54 normal people served as subjects. They were divided into three groups with ages of 24.8 +/- 2.6 years (N = 24), 40.2 +/- 8.3 years (N = 13) and 67.5 +/- 7.1 years (N = 17) respectively. Statistical t-tests were employed to evaluate the differences in MP density, the half width of MP distributed (HWMPD) in retina with respect to age between the groups. Linear regression was also applied to reveal the relationships of HWMPD distribution with respect to age.

RESULTS

The results indicate that the average MP densities are 0.23 +/- 0.08, 0.22 +/- 0.06 and 0.23 +/- 0.06 density unit (DU) for the young to old age groups. The average MP density is 0.23 +/- 0.07. No statistical significant difference is found in the peak MP density between the groups (all p > 0.05). This result pretty agrees with the data that obtained from others by using optical methods. For the young to old age groups, the average estimated HWMPD are 2.6 degrees +/- 0.5 degrees, 3.1 degrees +/- 0.5 degrees and 4.1 degrees +/- 0.6 degrees respectively. The differences between loci of HWMPD in the three groups are statistically significant with p = 0.0059, p < 0.0001 and p = 0.0001 for young vs. mid-age, young vs. old and mid-age vs. old respectively. Linear regressions for the HWMPD vs. age (r = 0.734, p < 0.001) implies that the macular pigment can gradually accumulate and spread out to the periphery of retina through our life span with an increase rate of approximately 0.03 degrees /year.

CONCLUSIONS

The accumulation of MP is reflected by the broader area in the macula lutea due to age, but no significant change is observed in peak density. The cause of the extension in the macular area with respect to age is unknown.

Clinical neurochemical implications of sleep deprivation's effects on the anterior cingulate of depressed responders

The antidepressant and cerebral metabolic effects of total sleep deprivation (TSD) or partial sleep deprivation (PSD) for one night has been studied with functional neuroimaging in seven publications from five different groups. Despite the variations in methods and techniques, the over-all findings were relatively consistent. First, before sleep deprivation, responders have significantly elevated metabolism compared with non-responders and normal controls, in the orbital medial prefrontal cortex, and especially the ventral portions of the anterior cingulate cortex. Second, after sleep deprivation, these hyperactive areas normalize in the responders. One functional imaging study suggested that synaptic dopamine release was associated with the antidepressant effects of TSD. The neurochemical implications of these findings are explored. Possible dopaminergic and serotonergic mechanisms are discussed.

Long-term evaluation of recombinant interferon alpha2b in the treatment of patients with hepatitis B e antigen-negative chronic hepatitis B in Taiwan

The effect of interferon (IFN) on hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) has not been fully investigated in Chinese patients. We enrolled 58 HBeAg-negative CHB Chinese patients with hepatitis B viremia in Taiwan to evaluate the response to IFN. 30 patients received recombinant IFN 5 million units 3 times weekly for 6-10 months, and 28 patients who refused IFN treatment served as controls. Rates of virological response and biochemical response were higher in the treated group at the end of treatment (57% vs 18%, P = 0.006, and 73% vs 29%, P = 0.002, respectively). Both effects were superior in the treated group at 6 months after IFN withdrawal (virological: 30% vs 7%, P = 0.06; biochemical: 47% vs 7%, P = 0.002). Improvement of liver histological activities with persistently biochemical response was found in 65% of the treated patients. After a mean of 32 months' follow-up, virological response was rarely maintained (17% vs 4%, P = 0.228) but biochemical response was better in the treated group (27% vs 4%, P = 0.039). None of the treated patients but five controls developed severe complications of CHB during the follow-up period. A larger total IFN dosage or a younger age (< or = 40 years) were associated with 'sustained' virological response. Younger age and higher baseline alanine transaminase values (> or = 120 Ul(-1)) were related to 'sustained' biochemical response.