[Advances of hydrogel in early protection of exposed intra-abdominal organs after open abdomen]

The protection of open abdomen (OA) wound is a significant subject in the field of trauma surgery. The key technical challenge in the early stage of OA wound management involves promoting granulation tissue filling between intestinal segments, reducing intestinal wall abrasion, and preventing the development of enteroatmospheric fistulas (EAF). Hydrogels, characterized by their high water content and exceptional biocompatibility, serve as extracellular matrix-mimicking materials, and are extensively employed in various medical and healthcare applications. In this review, we discuss the application of hydrogel developed by natural biomaterials in OA wounds protection, taking into consideration the unique pathophysiological characteristics of the OA wounds. This review aims to provide valuable insights for the development of hydrogel materials for early-stage OA wound protection in future research.

P–522 Cervical secretion methylation profile is associated with the success of frozen-thawed embryo transfer - a proof-of-concept study

Study question

Is cervical secretion gene methylation profile different between receptive and non-receptive endometrium and associated with implantation outcome in frozen-embryo transfer (FET) cycle?

Summary answer

The combination of candidate genes methylation profiles obtained from cervical secretion showed significant associations with pregnancy outcomes.

What is known already

Implantation failure remains a black box in reproductive medicine, and the exact mechanism of how endometrial receptivity is regulated is still unknown. Epigenetic modifications play a role in the gene expression pattern and may alter the endometrial receptivity in the human endometrium. Cervical secretion containing various implantation-related cytokines, and the gene methylation change can be used as a non-invasive molecular source that reflects the endometrium condition.

Study design, size, duration

In this retrospective case-control study, sixty-two women who entered the FET cycle (30 pregnant and 32 non-pregnant women) were enrolled.

Participants/materials, setting, methods

Cervical secretion was collected before embryo transfer from women enrolled in multicenter university-affiliated reproductive units. The DNA methylation status of six candidate genes was measured using quantitative methylation-specific PCR (qMSP). The correlation between methylation change and the pregnancy outcome was analyzed.

Main results and the role of chance

The candidate genes were selected from that associated with implantation with literature review and the original genome-wide DNA methylation data from NCBI GEO DataSets (GSE90060) which processed using bioinformatics analysis. Six candidate genes whose CpG-level methylation analysis with β-value statistically higher in receptive endometrium than in a pre-receptive endometrium were selected. All six candidate genes showed different degrees of correlation with the pregnancy outcomes. Among them, PRKAG2 methylation changes showed the highest correlation with the pregnancy outcome. A logistic regression model was used to evaluate the performance of a single gene or a combination of genes for implantation prediction. The results showed a statistically significant association between the methylation status of a combination of genes (PRKAG2, KRS1, HAND2) and the pregnancy outcome (p = 0.008), resulting in an optimal AUC of 0.7 (95% CI: 0.57 - 0.81) for implantation prediction.

Limitations, reasons for caution

The results obtained from a relatively small cohort size. A larger study and further comprehensive methylome investigations are warranted.

Wider implications of the findings: This study is the first proof-of-concept study that cervical secretion methylation profile is associated with implantation outcome in a FET cycle, and showed potential as a non-invasive method for implantation prediction.

Trial registration number

non applicable

Therapeutic Efficacy of Cryopreserved, Allogeneic Extracellular Vesicles for Treatment of Acute Myocardial Infarction

Extracellular vesicles (EV) that are derived from endothelial progenitor cells (EPC) have been determined to be a novel therapy for acute myocardial infarction, with a promise for immediate "off-the-shelf" delivery. Early experience suggests delivery of EVs from allogeneic sources is safe. Yet, clinical translation of this therapy requires assurances of both EV stability following cryopreservation and absence of an adverse immunologic response to EVs from allogeneic donors. Thus, more bioactivity studies on allogeneic EVs after cold storage are necessary to establish quality standards for its widespread clinical use. Thus, in this study, we aimed to demonstrate the safety and efficacy in delivering cryopreserved EVs in allogeneic recipients as a therapy for acute myocardial infarction.In this present study, we have analyzed the cardioprotective effects of allogeneic EPC-derived EVs after storage at -80°C for 2 months, using a shear-thinning gel (STG) as an in vivo delivery vehicle. EV size, proteome, and nucleic acid cargo were observed to remain steady through extended cryopreservation via nanoparticle tracking analysis, mass spectrometry, and nanodrop analysis, respectively. Fresh and previously frozen EVs in STG were delivered intramyocardially in a rat model of myocardial infarction (MI), with both showing improvements in contractility, angiogenesis, and scar thickness in comparison to phosphate-buffered saline (PBS) and STG controls at 4 weeks post-MI. Pathologic analyses and flow cytometry revealed minimal inflammatory and immune upregulation upon exposure of tissue to EVs pooled from allogeneic donor cells.Allogeneic EPC-EVs have been known to elicit minimal immune activity and retain therapeutic efficacy after at least 2 months of cryopreservation in a post-MI model.

[Clinical cure strategy for hepatitis B: immunomodulatory therapy]

Chronic hepatitis B virus (HBV) infection remains a major world public health problem. Current guidelines of chronic hepatitis B (CHB) suggest the clinical cure as the ideal thearapeutic goal. Although the optimization of the existing antiviral treatment can make some patients achieve clinical cure, but for most patients with chronic hepatitis B, it is difficult to achieve clinical cure according to the existing antiviral treatment plan. The medical community has begun to work together to seek new treatment strategies, especially the immune intervention measures aimed at restoring the immune response in the liver microenvironment. Notably, immune antiviral response plays a crucial role in HBV clearance, and the clinical cure of chronic hepatitis B is finally achieved through the optimized combination of antiviral and immunomodulatory drugs.

Delayed delivery of endothelial progenitor cell-derived extracellular vesicles via shear thinning gel improves postinfarct hemodynamics

BACKGROUND

Extracellular vesicles (EVs) are promising therapeutics for cardiovascular disease, but poorly-timed delivery might hinder efficacy. We characterized the time-dependent response to endothelial progenitor cell (EPC)-EVs within an injectable shear-thinning hydrogel (STG+EV) post-myocardial infarction (MI) to identify when an optimal response is achieved.

METHODS

The angiogenic effects of prolonged hypoxia on cell response to EPC-EV therapy and EV uptake affinity were tested in vitro. A rat model of acute MI via left anterior descending artery ligation was created and STG+EV was delivered via intramyocardial injections into the infarct border zone at time points corresponding to phases of post-MI inflammation: 0 hours (immediate), 3 hours (acute inflammation), 4 days (proliferative), and 2 weeks (fibrosis). Hemodynamics 4 weeks post-treatment were compared across treatment and control groups (phosphate buffered saline [PBS], shear-thinning gel). Scar thickness and ventricular diameter were assessed histologically. The primary hemodynamic end point was end systolic elastance. The secondary end point was scar thickness.

RESULTS

EPC-EVs incubated with chronically versus acutely hypoxic human umbilical vein endothelial cells resulted in a 2.56 ± 0.53 versus 1.65 ± 0.15-fold increase (P = .05) in a number of vascular meshes and higher uptake of EVs over 14 hours. End systolic elastance improved with STG+EV therapy at 4 days (0.54 ± 0.08) versus PBS or shear-thinning gel (0.26 ± 0.03 [P = .02]; 0.23 ± 0.02 [P = .01]). Preservation of ventricular diameter (6.20 ± 0.73 mm vs 8.58 ± 0.38 mm [P = .04]; 9.13 ± 0.25 mm [P = .01]) and scar thickness (0.89 ± 0.05 mm vs 0.62 ± 0.03 mm [P < .0001] and 0.58 ± 0.05 mm [P < .0001]) was significantly greater at 4 days, compared wit PBS and shear-thinning gel controls.

CONCLUSIONS

Delivery of STG+EV 4 days post-MI improved left ventricular contractility and preserved global ventricular geometry, compared with controls and immediate therapy post-MI. These findings suggest other cell-derived therapies can be optimized by strategic timing of therapeutic intervention.

Urban-rural disparity of preventive healthcare utilisation among children under the universal health insurance coverage in Taiwan: a national birth cohort analysis

OBJECTIVE

In the context of universal health insurance coverage, this study aimed to determine whether urban-rural inequality still exists in preventive health care (PHC) amongst children in Taiwan.

STUDY DESIGN

Prospective cohort study.

METHODS

A total of 184,117 mothers and their children born in 2009 were identified as the study cohort. The number of children born in urban, satellite and rural areas was 40,176, 57,565 and 86,805, respectively. All children were followed for 7 years, before which a total of seven times PHC were provided by Taiwan's National Health Insurance (NHI) programme. Ordinal logistic regression models were used to associate urbanisation level with the frequency of PHC utilisation. Stratified analyses were further performed in accordance with the children's birth weight and the mothers' birthplace.

RESULTS

Children from satellite areas had higher utilisation for the first four scheduled PHC visits. Children living in urban areas received more PHC for the fifth and sixth scheduled visits. Compared with those from rural areas, children in satellite areas exhibited a small but significant increase in odds in PHC utilisation, with a covariate-adjusted odds ratio (aOR) of 1.04 and 95% confidence interval (CI) of 1.02-1.06. By contrast, no significant difference was observed between rural and urban areas (aOR = 1.01). Further stratified analyses suggest more evident urban-rural difference in PHC utilisation amongst children with low birth weight and foreign-born mothers.

CONCLUSIONS

Given a universal health insurance coverage and embedded mechanisms in increasing the availability of healthcare resources in Taiwan, a slight urban-rural difference is observed in PHC utilisation amongst children. Hence, sociodemographic inequality in utilisation of PHC still exists. This issue should be addressed through policy intervention.

[Several issues worthy of reference and discussion of 2019 edition of the European Association for the Study of the Liver guideline for drug-induced liver injury]

The 2019 European Association for the Study of the Liver (EASL) Clinical Practice Guidelines (hereinafter referred to as the EASL Guidelines) extracted the required evidence from detailed research materials, and rigorously graded and condensed the varying strengths of evidence into 32 recommendations and 14 statements (recommendations and reminders) for drug-induced Liver Injury (DILI). This guideline has important reference values for helping clinicians to further improve their understanding of DILI and the level of clinical diagnosis, treatment and prevention; however, there are still several issues worthy of further discussion.

Expression and prognostic significance of melatonin receptor MT1 in patients with gastric adenocarcinoma

Melatonin receptor type 1 (MTNR1A or MT1) is known to play an important role in cancer progression; however, its prognostic value for resected gastric adenocarcinoma (RGA) is unknown. In this study, we examined the potential of MT1 as a prognostic biomarker for RGA. The expression of the MT1 was evaluated in 67 patients with RGA by immunohistochemistry, and the relationship between MT1 levels and RGA prognosis was analyzed by Chi-square test, multivariate Cox regression, Kaplan-Meier method, and log-rank test. High MT1 expression was associated with a poor survival rate (29.0%, p=0.002) and the occurrence of metastasis (62.9%, p=0.004). Kaplan-Meier survival analysis and log rank tests revealed that patients with high expression of the MT1 had significantly shorter median overall survival compared to those with low expression (33.0 vs. 65.0 months, respectively; p=0.02). Multivariate Cox analysis indicated that the calculated death risk (hazard ratio [HR]) in patients with high expression levels of the MT1 increased to 2.68 (95% confidence interval [CI] 1.21-5.94, p=0.015), which was higher compared to those with low levels. HR of death was also high in patients with advanced T stage (2.51; 95 % CI 1.00-6.26, p=0.049) and metastasis (5.02; 95% CI 1.94-13.03, p=0.001). Our results showed that high MT1 expression in primary gastric adenocarcinoma tissues was associated with the occurrence of metastasis and poor prognosis. It may have prognostic significance as a potential biomarker in patients with RGA.

[Investigation of treatment and analysis of prognostic risk on enterocutaneous fistula in China: a multicenter prospective study]

Objective: To investigate the diagnosis and treatment for enterocutaneous fistula (ECF) in China, and to explore the prognostic factors of ECF. Methods: A multi-center cross-sectional study was conducted based on the Registration System of Chinese Gastrointestinal Fistula and Intra-Abdominal Infections to collect the clinical data of ECF patients from 54 medical centers in 22 provinces/municipalities from January 1, 2018 to December 31, 2018. The clinical data included patient gender, age, length of hospital stay, intensive care unit (ICU) admission, underlying diseases, primary diseases, direct causes of ECF, location and type of ECF, complications, treatment and outcomes. All medical records were carefully filled in by the attending physicians, and then re-examined by more than two specialists. The diagnosis of ECF was based on the clinical manifestations, laboratory/imaging findings and intraoperative exploration. Results: A total of 1521 patients with ECF were enrolled, including 1099 males and 422 females, with a median age of 55 years. The top three primary diseases of ECF were malignant tumors in 626 cases (41.2%, including 540 gastrointestinal tumors, accounting for 86.3% of malignant tumors), gastrointestinal ulcers and perforations in 202 cases (13.3%), and trauma in 157 cases (10.3%). The direct causes of ECF were mainly surgical operation in 1194 cases (78.5%), followed by trauma in 156 (10.3%), spontaneous fistula due to Crohn's disease in 92 (6.0%), radiation intestinal injury in 41 (2.7%), severe pancreatitis in 20 (1.3%), endoscopic treatment in 13 (0.9%) and 5 cases (0.3%) of unknown reasons. All the patients were divided into three groups: 1350 cases (88.7%) with simple ECF, 150 (9.9%) with multiple ECF, and 21 (1.4%) with combined internal fistula. Among the patients with simple ECF, 438 cases (28.8%) were jejuno-ileal fistula, 313 (20.6%) colon fistula, 170 (11.2%) rectal fistula, 111 (7.3%) duodenal fistula, 76 (5.0%) ileocecal fistula, 65 (4.3%) ileocolic anastomotic fistula, 55 (3.6%) duodenal stump fistula, 36 (2.4%) gastrointestinal anastomotic fistula, 36 (2.4%) esophagogastric/esophagojejunal anastomotic fistula, 29 (1.9%) gastric fistula and 21 (1.4%) cholangiopancreatiointestinal. Among all the simple ECF patients, 991 were tubular fistula and 359 were labial fistula. A total of 1146 patients finished the treatment, of whom 1061 (92.6%) were healed (586 by surgery and 475 self-healing) and 85 (7.4%) died. A total of 1043 patients (91.0%) received nutritional support therapy, and 77 (6.7%) received fistuloclysis. Infectious source control procedures were applied to 1042 patients, including 711 (62.0%) with active lavage and drainage and 331 (28.9%) with passive drainage. Among them, 841 patients (73.4%) underwent minimally invasive procedures of infectious source control (replacement of drainage tube through sinus tract, puncture drainage, etc.), 201 (17.5%) underwent laparotomy drainage, while 104 (9.1%) did not undergo any drainage measures. A total of 610 patients (53.2%) received definitive operation, 24 patients died within postoperative 30-day with mortality of 3.9% (24/610), 69 (11.3%) developed surgical site infection (SSI), and 24 (3.9%) had a relapse of fistula. The highest cure rate was achieved in ileocecal fistula (100%), followed by rectal fistula (96.2%, 128/133) and duodenal stump fistula (95.7%,44/46). The highest mortality was found in combined internal fistula (3/12) and no death in ileocecal fistula. Univariate prognostic analysis showed that primary diseases as Crohn's disease (χ(2)=6.570, P=0.010) and appendicitis/appendiceal abscess (P=0.012), intestinal fistula combining with internal fistula (χ(2)=5.460, P=0.019), multiple ECF (χ(2)=7.135, P=0.008), esophagogastric / esophagojejunal anastomotic fistula (χ(2)=9.501, P=0.002), ECF at ileocecal junction (P=0.012), non-drainage/passive drainage before the diagnosis of intestinal fistula (χ(2)=9.688, P=0.008), non-drainage/passive drainage after the diagnosis of intestinal fistula (χ(2)=9.711, P=0.008), complicating with multiple organ dysfunction syndrome (MODS) (χ(2)=179.699, P<0.001), sepsis (χ(2)=211.851, P<0.001), hemorrhage (χ(2)=85.300, P<0.001), pulmonary infection (χ(2)=60.096, P<0.001), catheter-associated infection (χ(2)=10.617, P=0.001) and malnutrition (χ(2)=21.199, P<0.001) were associated with mortality. Multivariate prognostic analysis cofirmed that sepsis (OR=7.103, 95%CI:3.694-13.657, P<0.001), complicating with MODS (OR=5.018, 95%CI:2.170-11.604, P<0.001), and hemorrhage (OR=4.703, 95%CI: 2.300-9.618, P<0.001) were independent risk factors of the death for ECF patients. Meanwhile, active lavage and drainage after the definite ECF diagnosis was the protective factor (OR=0.223, 95%CI: 0.067-0.745, P=0.015). Conclusions: The overall mortality of ECF is still high. Surgical operation is the most common cause of ECF. Complications e.g. sepsis, MODS, hemorrhage, and catheter-associated infection, are the main causes of death. Active lavage and drainage is important to improve the prognosis of ECF.

Sustained release of endothelial progenitor cell-derived extracellular vesicles from shear-thinning hydrogels improves angiogenesis and promotes function after myocardial infarction

Aims

Previous studies have demonstrated improved cardiac function following myocardial infarction (MI) after administration of endothelial progenitor cells (EPCs) into ischaemic myocardium. A growing body of literature supports paracrine effectors, including extracellular vesicles (EVs), as the main mediators of the therapeutic benefits of EPCs. The direct use of paracrine factors is an attractive strategy that harnesses the effects of cell therapy without concerns of cell engraftment or viability. We aim to reproduce the beneficial effects of EPC treatment through delivery of EPC-derived EVs within a shear-thinning gel (STG) for precise localization and sustained delivery.

Methods and results

EVs were harvested from EPCs isolated from adult male Rattus norvegicus (Wistar) rats and characterized by electron microscopy, nanoparticle tracking analysis (NTA), and mass spectrometry. EVs were incorporated into the STG and injected at the border zone in rat models of MI. Haemodynamic function, angiogenesis, and myocardial remodelling were analyzed in five groups: phosphate buffered saline (PBS) control, STG control, EVs in PBS, EVs in STG, and EPCs in STG. Electron microscopy and NTA of EVs showed uniform particles of 50-200 nm. EV content analysis revealed several key angiogenic mediators. EV uptake by endothelial cells was confirmed and followed by robust therapeutic angiogenesis. In vivo animal experiments demonstrated that delivery of EVs within the STG resulted in increased peri-infarct vascular proliferation, preservation of ventricular geometry, and improved haemodynamic function post-MI.

Conclusions

EPC-derived EVs delivered into ischaemic myocardium via an injectable hydrogel enhanced peri-infarct angiogenesis and myocardial haemodynamics in a rat model of MI. The STG greatly increased therapeutic efficiency and efficacy of EV-mediated myocardial preservation.

[Clinical effect and safety of pegylated interferon-α-2b injection (Y shape, 40 kD) in treatment of HBeAg-positive chronic hepatitis B patients]

Objective: To investigate the clinical effect and safety of long-acting pegylated interferon-α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 μg/week) in the treatment of HBeAg-positive chronic hepatitis B (CHB) patients, with standard-dose Peg-IFN-α-2a as positive control. Methods: This study was a multicenter, randomized, open-label, and positive-controlled phase III clinical trial. Eligible HBeAg-positive CHB patients were screened out and randomized to Peg-IFN-α-2b (Y shape, 40 kD) trial group and Peg-IFN-α-2a control group at a ratio of 2:1. The course of treatment was 48 weeks and the patients were followed up for 24 weeks after drug withdrawal. Plasma samples were collected at screening, baseline, and 12, 24, 36, 48, 60, and 72 weeks for centralized detection. COBAS® Ampliprep/COBAS® TaqMan® HBV Test was used to measure HBV DNA level by quantitative real-time PCR. Electrochemiluminescence immunoassay with Elecsys kit was used to measure HBV markers (HBsAg, anti-HBs, HBeAg, anti-HBe). Adverse events were recorded in detail. The primary outcome measure was HBeAg seroconversion rate after the 24-week follow-up, and non-inferiority was also tested. The difference in HBeAg seroconversion rate after treatment between the trial group and the control group and two-sided confidence interval (CI) were calculated, and non-inferiority was demonstrated if the lower limit of 95% CI was > -10%. The t-test, chi-square test, or rank sum test was used according to the types and features of data. Results: A total of 855 HBeAg-positive CHB patients were enrolled and 820 of them received treatment (538 in the trial group and 282 in the control group). The data of the full analysis set showed that HBeAg seroconversion rate at week 72 was 27.32% in the trial group and 22.70% in the control group with a rate difference of 4.63% (95% CI -1.54% to 10.80%, P = 0.1493). The data of the per-protocol set showed that HBeAg seroconversion rate at week 72 was 30.75% in the trial group and 27.14% in the control group with a rate difference of 3.61% (95% CI -3.87% to 11.09%, P = 0.3436). 95% CI met the non-inferiority criteria, and the trial group was non-inferior to the control group. The two groups had similar incidence rates of adverse events, serious adverse events, and common adverse events. Conclusion: In Peg-IFN-α regimen for HBeAg-positive CHB patients, the new drug Peg-IFN-α-2b (Y shape, 40 kD) has comparable effect and safety to the control drug Peg-IFN-α-2a.

[Experimental study of silybin-phospholipid complex intervention on amiodarone-induced fatty liver in mice]

Objective: To probe into the mechanism and interventional effects of silybin-phospholipid complex on amiodarone-induced steatosis in mice. Methods: Eight-week-old male C57BL/6 mice were divided into three groups (5 mice in each group): a control group (WT) with normal diet, a model group with amiodarone 150mg/kg/d by oral gavage (AM), and an intervention group on amiodarone 150mg/kg/d combined with silybin-phospholipid complex(AM+SILIPHOS. All mice were fed their assigned diet for one week. Then, one week later, serum alanine aminotransferase, aspartate aminotransferase, triglyceride, total cholesterol and high-density lipoprotein were detected of each group. A liver pathological change was observed by oil red O and H&E staining. Ultrastructural pathological changes of hepatocytes were observed to evaluate the intervention effect by transmission electron microscopy. RT-q PCR was used to detect the expression of peroxisome proliferator-activated receptor alpha and its regulated lipid metabolism genes CPTI, CPTII, Acot1, Acot2, ACOX, Cyp4a10 and Cyp4a14 in liver tissues. Intra-group comparison was done by paired t-test. One-way ANOVA was used for comparison between groups and semi-quantitative data were tested using Mann-Whitney U test. Results: Oil Red O and H&E staining results of liver tissue in the intervention group showed that intrahepatic steatosis was significantly reduced when compared to model group. Transmission electron microscopy showed that the model group had pyknotic nuclei, mitochondrial swelling, structural damage, and lysosomal degradation whereas the intervention group had hepatic nucleus without pyknosis, reduced mitochondrial swelling and slight structural damage than that of model group. RT-q PCR results showed that the expression of peroxisome proliferator-activated receptor alpha, CPTI, CPTII, Acot1, Acot2, ACOX, Cyp4a10 and Cyp4a14 were increased in the model group but the expression of CPTI, Cyp4a14, Acot1 and peroxisome proliferator-activated receptor alpha were decreased in the intervention group (P < 0.05). Conclusion: Silybin-phospholipid complex can alleviate amiodarone-induced steatosis, and its mechanism may play a role in protecting mitochondrial function and regulating fatty acid metabolism. Thus, silybin-phospholipid complex has potential intervention effect on amiodarone-induced fatty liver.

Removal of sulfonamides from wastewater in the UV/TiO2 system: effects of pH and salinity on photodegradation and mineralization

The effects of salinity on the photodegradation and mineralization of sulfonamides in the UV/TiO₂ system were investigated. The goals of this study were to analyze the effects of pH and salinity on the sulfonamide concentration and total organic carbon (TOC) during the removal of sulfonamides in a UV/TiO₂ system. Four sulfonamides - sulfadiazine (SDZ), sulfamethizole (SFZ), sulfamethoxazole (SMX) and sulfathiazole (STZ) - were selected as parent compounds. The photodegradation and mineralization rates of sulfonamides in the UV/TiO₂ system satisfy pseudo-first-order kinetics. Direct photolysis degraded sulfonamides but sulfonamides cannot be mineralized. The photodegradation and mineralization rate constants in all experiments followed the order pH 5 > pH 7 > pH 9. At pH 5, the mineralization rate constants of SMX, SFZ, SDZ and STZ were 0.015, 0.009, 0.012 and 0.011 min^-1, respectively. The addition of NaCl inhibited the mineralization of the four tested sulfonamides more than it inhibited their photodegradation. The inhibitory effect of chloride ions on the removal of sulfonamides in the UV/TiO₂ system was attributed to the scavenging by chloride ions of hydroxyl radicals (HO•) and holes and the much lower reactivity of chlorine radicals thus formed, even though the chlorine radicals were more abundant than HO•.

Delivery of progenitor cells with injectable shear-thinning hydrogel maintains geometry and normalizes strain to stabilize cardiac function after ischemia

OBJECTIVES

The ventricle undergoes adverse remodeling after myocardial infarction, resulting in abnormal biomechanics and decreased function. We hypothesize that tissue-engineered therapy could minimize postischemic remodeling through mechanical stress reduction and retention of tensile myocardial properties due to improved endothelial progenitor cell retention and intrinsic biomechanical properties of the hyaluronic acid shear-thinning gel.

METHODS

Endothelial progenitor cells were harvested from adult Wistar rats and resuspended in shear-thinning gel. The constructs were injected at the border zone of ischemic rat myocardium in an acute model of myocardial infarction. Myocardial remodeling, tensile properties, and hemodynamic function were analyzed: control (phosphate-buffered saline), endothelial progenitor cells, shear-thinning gel, and shear-thinning gel + endothelial progenitor cells. Novel high-resolution, high-sensitivity ultrasound with speckle tracking allowed for global strain analysis. Uniaxial testing assessed tensile biomechanical properties.

RESULTS

Shear-thinning gel + endothelial progenitor cell injection significantly increased engraftment and retention of the endothelial progenitor cells within the myocardium compared with endothelial progenitor cells alone. With the use of strain echocardiography, a significant improvement in left ventricular ejection fraction was noted in the shear-thinning gel + endothelial progenitor cell cohort compared with control (69.5% ± 10.8% vs 40.1% ± 4.6%, P = .04). A significant normalization of myocardial longitudinal displacement with subsequent stabilization of myocardial velocity with shear-thinning gel + endothelial progenitor cell therapy compared with control was also evident (0.84 + 0.3 cm/s vs 0.11 ± 0.01 cm/s, P = .03). A significantly positive and higher myocardial strain was observed in shear-thinning gel + endothelial progenitor cell (4.5% ± 0.45%) compared with shear-thinning gel (3.7% ± 0.24%), endothelial progenitor cell (3.5% ± 0.97%), and control (8.6% ± 0.3%, P = .05). A resultant reduction in dynamic stiffness was noted in the shear-thinning gel + endothelial progenitor cell cohort.

CONCLUSIONS

This novel injectable shear-thinning hyaluronic acid hydrogel demonstrates stabilization of border zone myocardium with reduction in adverse myocardial remodeling and preservation of myocardial biomechanics. The cellular construct provides a normalization of strain measurements and reduces left ventricular dilatation, thus resulting in improvement of left ventricular function.

Better With Time: An Economic Assessment of Long-Term Mechanical Circulatory Support in a Population Surviving at Least 1 Year with a Left Ventricular Assist Device

This study aims to identify the major components of left ventricular assist device (LVAD)-related costs in a population on long-term mechanical circulatory support to gain insight into opportunities for improvements in quality, safety, and efficiency of care for end-stage heart failure patients. This was a single institution, retrospective cost analysis of patients who received a Heartmate II or HeartWare LVAD between November 2005 and October 2015. Payments for hospitalization for device implantation and subsequent readmissions were represented as the institution's 2015 Medicare reimbursement rate. The incidence, average Medicare reimbursement, and length of stay of readmissions were analyzed for the first year postimplant. A full year of LVAD-related hospitalizations in patients surviving ≥12 months, has a median Medicare reimbursement of $247,208. The most common complications related to ventricular assist devices were gastrointestinal bleeding, driveline infection, stroke, and pump thrombosis. Over 90% of total costs were incurred during the initial hospitalization. Seventy-five percent of first-time readmissions occurred within the first 4 months post discharge. Intensive care unit costs accounted for the single largest cost category during readmissions for all of the 4 most common complications. The trends demonstrated suggest that longer lengths of LVAD support in appropriately selected patients results in progressively decreasing cost-per-month up to 12 months, given the large upfront cost of device implantation and relatively modest additional costs of readmissions. This analysis emphasizes the importance of devices with improved complication profiles and clinical protocols to reduce unnecessary intensive care unit stays to increase the cost effectiveness of long-term ventricular assist device therapy.

Preoperative renal dysfunction does not affect outcomes of left ventricular assist device implantation

OBJECTIVE

Selection criteria for durable left ventricular assist device (LVAD) implantation remain unclear. One such criterion is renal function. In this study we evaluated outcomes of LVAD implantation in patients with preoperative renal dysfunction.

METHODS

Patients with implanted LVADs as destination therapy (DT) or bridge to transplantation (BTT) at a single institution between 2006 and 2015 were included. Primary stratification was according to pre-implantation glomerular filtration rate (GFR): >60 mL/min versus <60 mL/min or dialysis dependence. The primary outcome was post-LVAD implantation overall survival.

RESULTS

Two hundred thirty-eight patients underwent LVAD implantation during the study period as DT (60%; n = 142) or BTT (40%; n = 96). Reduced GFR was present in 56% (n = 132), with 8% (n = 18) being dialysis-dependent. Normal versus reduced GFR cohorts were well matched except for a higher incidence of coronary artery disease in the patients with reduced GFR (61% vs 48%; P = .04). Mean follow-up was 13.5 ± 17.0 months. Unadjusted and risk-adjusted survival at 1, 3, 6, and 12 months after LVAD implantation were similar between the cohorts for DT and BTT. Rates of transplantation were comparable in BTT patients (61% normal vs 53% reduced GFR; P = .43). Recovery of renal function to a GFR >60 mL/min occurred in 43% (n = 17) and 57% (n = 42) of patients with reduced GFR in the BTT and DT cohorts, respectively, by 1 year post implantation.

CONCLUSIONS

Well selected patients with preexisting renal dysfunction can undergo LVAD implantation with acceptable outcomes. Approximately half of LVAD recipients with preimplantation renal dysfunction will recover normal renal function within the first postoperative year. Renal dysfunction alone should not serve as an absolute contraindication to LVAD therapy.

Source identification and ecological impact evaluation of PAHs in urban river sediments: A case study in Taiwan

The Love River and Ho-Jin River, two major urban rivers in Kaohsiung City, Taiwan, are moderately to heavily polluted because different types of improperly treated wastewaters are discharged into the rivers. In this study, sediment and river water samples were collected from two rivers to investigate the river water quality and accumulation of polycyclic aromatic hydrocarbons (PAHs) in sediments. The spatial distribution, composition, and source appointment of PAHs of the sediments were examined. The impacts of PAHs on ecological system were assessed using toxic equivalence quotient (TEQ) of potentially carcinogenic PAHs (TEQ^carc) and sediment quality guidelines. The average PAHs concentrations ranged from 2161 ng/g in Love River sediment to 160 ng/g in Ho-Jin River sediment. This could be due to the fact that Love River Basin had much higher population density and pyrolytic activities. High-ring PAHs (4-6 rings) contributed to 59-90% of the total PAHs concentrations. Benzo(a)pyrene (BaP) had the highest toxic equivalence quotient (up to 188 ng TEQ/g). Moreover, the downstream sediments contained higher TEQ of total TPHs than midstream and upstream sediment samples. The PAHs were adsorbed onto the fine particles with high organic content. Results from diagnostic ratio analyses indicate that the PAHs in two urban river sediments might originate from oil/coal combustion, traffic-related emissions, and waste combustion (pyrogenic activities). Future pollution prevention and management should target the various industries, incinerators, and transportation emission in this region to reduce the PAHs pollution.

Is there a difference in bleeding after left ventricular assist device implant: centrifugal versus axial?

BACKGROUND

Continuous-flow left ventricular assist devices (CF-LVAD) have become the standard of care for patients with end stage heart failure. Device reliability has increased, bringing the potential for VAD, compared to transplant, into debate. However, complications continue to limit VADs as first line therapy. Bleeding is a major morbidity. A debate exists as to the difference in bleeding profile between the major centrifugal and axial flow devices. We hypothesized that there would be similar adverse bleeding event profiles between the 2 major CF-LVADs.

METHODS

We retrospectively investigated isolated CF LVADs performed at our institution between July 2010 and July 2015: HeartMateII (HMII, n = 105) and HeartWare (HVAD, n = 34). We reviewed demographic, perioperative and short- and long-term outcomes.

RESULTS

There was no significant difference in demographics or comorbidities. There was a low incidence of gastrointestinal (GI) bleed 3.9% in HMII and 2.9% in HVAD (p = 0.78). Preoperatively, the cohorts did not differ in coagulation measures (p = 0.95). Within the post-operative period, there was no difference in product transfusion: red blood cells (p = 0.10), fresh frozen plasma (p = 0.19), and platelets (p = 0.89). Post-operatively, a higher but not significantly different number of HMII patients returned to the operating room for bleeding (n = 27) compared to HVAD (n = 6, p = 0.35). There was no difference in rates of stroke (p = 0.65), re-intubation (p = 0.60), driveline infection (p = 0.05), and GI bleeding (p = 0.31). The patients had equivalent ICU LOS (p = 0.86) and index hospitalization LOS (p = 0.59).

CONCLUSION

We found no difference in the rate of bleeding complications between the current commercially available axial and centrifugal flow devices.

NMR-based metabolomics for the environmental assessment of Kaohsiung Harbor sediments exemplified by a marine amphipod (Hyalella azteca)

Inflow of wastewater from upstream causes a large flux of pollutants to enter Kaohsiung Harbor in Taiwan daily. To reveal the ecological risk posed by Kaohsiung Harbor sediments, an ecological metabolomic approach was employed to investigate environmental factors pertinent to the physiological regulation of the marine amphipod Hyalella azteca. The amphipods were exposed to sediments collected from different stream inlets of the Love River (LR), Canon River (CR), Jen-Gen River (JR), and Salt River (SR). Harbor entrance 1 (E1) was selected as a reference site. After 10-day exposure, metabolomic analysis of the Hyalella azteca revealed differences between two groups: {E1, LR, CR} and {JR, SR}. The metabolic pathways identified in the two groups of amphipods were significantly different. The results demonstrated that NMR-based metabolomics can be effectively used to characterize metabolic response related to sediment from polluted areas.

[Efficacy and safety of pegylated interferon α-2b injection (Y shape, 40 kD) in treatment of patients with genotype 1/6 chronic hepatitis C]

Objective: To investigate the efficacy and safety of the new investigational drug pegylated interferon α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 µg/week) combined with ribavirin in the treatment of patients with genotype 1/6 chronic hepatitis C (CHC), with standard-dose Peg-IFN-α-2a combined with ribavirin as a positive control. Methods: A multicenter, randomized, open-label, and positive-controlled phase III clinical trial was performed. Eligible patients with genotype 1/6 CHC were screened out and randomly divided into Peg-IFN-α-2b(Y shape, 40kD) group and Peg-IFN-α-2a group at a ratio of 2:1. The patients in both groups were given oral ribavirin for 48 weeks in addition and then followed up for 24 weeks after drug withdrawal. Abbott Real Time HCV Genotype II was used to determine HCV genotype, and Cobas TaqMan quantitative real-time PCR was used to measure HCV RNA level at 0, 4, 12, 24, 48, and 72 weeks. Adverse events were recorded in detail. The primary efficacy endpoint was sustained virological response (SVR), and a non-inferiority test was also performed. Results: A total of 561 patients with genotype 1/6 CHC were enrolled, among whom 529 received treatment; 90.9% of these patients had genotype 1 CHC. The data of the full analysis set showed that SVR rate was 69.80% (95% CI 65.00%-74.60%) in the trial group and 74.16% (95% CI 67.73%-80.59%) in the control group (P = 0.297 0). The data of the per protocol set (PPS) showed that SVR rate was 80.63% (95% CI 76.04%-85.23%) in the trial group and 81.33% (95% CI 75.10%-87.57%) in the control group (P = 0.849 8), and the 95% CI of rate difference conformed to the non-inferiority standard. The analysis of the PPS population showed that of all subjects, 47.9% achieved rapid virologic response, with a positive predictive value of 93.8%. The incidence rate of adverse events was 96.30% in the trial group and 94.94% in the control group, and the incidence rate of serious adverse events was 5.13% in the trail group and 5.06% in the control group. Conclusion: In the regimen of Peg-IFN-α combined with ribavirin for the treatment of genotype 1/6 CHC, the new investigational drug Peg-IFN-α-2b(Y shape, 40 kD) has comparable clinical effect and safety to the control drug Peg-IFN-α-2a.

Improved Approach With Subcostal Exchange of the HeartMate II Left Ventricular Assist Device: Difference in On and Off Pump?

BACKGROUND

The HeartMate II (St. Jude Medical, Inc, St. Paul, MN [previously Thoratec]) left ventricular assist device (LVAD) exchange has traditionally involved a redo sternotomy. Alternate minimally invasive subcostal approaches have the advantage of avoiding sternal reentry, excessive bleeding, and prolonged recovery.

METHODS

This retrospective review included patients who underwent an exchange from May 2009 to March 2016. The patients were divided into three cohorts: (1) redo sternotomy, (2) subcostal approach involving cardiopulmonary bypass (CPB) (ON-CPB SC), and (3) subcostal approach off the CPB pump (OFF-CPB SC). Data pertaining to patients' baseline characteristics and outcomes were collected and analyzed.

RESULTS

From May 1, 2009 to July 31, 2016, 33 HeartMate II LVAD exchanges were performed. There were 11 redo sternotomies and 22 subcostal exchanges, 12 of which were in the OFF-CPB SC group. There was no significant difference among the groups in terms of age (p = 0.75), sex (p = 0.95), and indication for exchange (p = 0.94). There was a higher red blood cell transfusion requirement within the sternotomy cohort (p < 0.001). The median time to extubation and the intensive care unit length of stay were significantly shorter in the OFF-CPB SC group (1 and 2.5 days, respectively) than in the sternotomy (2.5 and 21 day, respectively) and ON-CPB SC groups (1.5 and 5 days, respectively). The 30-day and 90-day survival rates were equivalent among the cohorts.

CONCLUSIONS

Exchange of the HeartMate II LVAD can be accomplished with significantly improved recovery time and transfusion requirement through a less invasive subcostal approach when compared with sternotomy. The subcostal approach can be performed safely both on and off cardiopulmonary bypass.

Non-cardiac surgery in patients with continuous-flow left ventricular assist devices: a single institutional experience

With improvements in life expectancy for patients with continuous-flow left ventricular assist devices (LVADs), non-cardiac surgeons will increasingly encounter surgical problems in this population. 209 patients underwent LVAD placement between 10/1/2007 and 6/1/2015 at a single institution. Survival was compared between patients who had non-cardiac surgery (NCS) during the initial LVAD implantation hospitalization (n=36) and those who had NCS only in subsequent hospitalizations (n=33). Postoperative complication rates were examined. Index admission NCS was associated with lower 5-year survival compared with subsequent admission NCS (27.1% vs 39.4%, p=0.017). In subsequent admissions, the risks of bleeding and infectious complications were the same for elective or urgent NCS, but the risk of death was higher in the urgent surgery group. We conclude that elective NCS can be performed with low risk of death or LVAD dysfunction after sufficient recovery of patients from LVAD implantation.

Bridge with a left ventricular assist device to a simultaneous heart and kidney transplant: Review of the United Network for Organ Sharing database

BACKGROUND

Left ventricular assist device (LVAD) implantation as a bridge to cardiac transplantation (BTT) is an effective treatment for end-stage heart failure patients. Currently, there is an increasing number of patients with a LVAD who need a heart and kidney transplant (HKT). Little is known of the prognostic outcomes in these patients. This study was undertaken to determine whether an equivalent outcome would be present in HKTs as compared to a non-LVAD primary HKT cohort.

METHODS

We reviewed the United Network for Organ Sharing database from 2004 to 2013. Orthotropic heart transplant recipients (n = 49 799) were subcategorized as dual organ HKT (n = 1 921) and then divided into cohorts of HKT following continuous flow left ventricular assist device placement (CF-VAD-HKT, n = 113) or no LVAD placement (HKT, n = 1 808). Survival after transplantation was analyzed.

RESULTS

For CF-LVAD-HKT and HKT cohorts, preoperative characteristics were similar regarding age (50.8 ± 13.7, 50.1 ± 13.7, p = 0.75) and panel reactive antibody (12.3 ± 18.4 vs 7.1 ± 18.4, p = 0.06). Donors were similar in age, gender, creatinine, and ejection fraction. Post-transplant, there was no difference in complications. Survival for CF-LVAD-HKT and HKT were similar at 1 year (77% vs 82%) and 3 years (75% vs 77%, log rank p = 0.2814).

CONCLUSIONS

For patients with advanced heart failure and persistent renal dysfunction, simultaneous HKT is a safe option. Survival after CF-LVAD-HKT is equivalent to conventional HKT.

[Carefully reviewing the history of diagnostic scales and paying more attention to the diagnostic value of Roussel - Uclaf causality assessment method scale for drug - induced liver injury]

Currently, the diagnostic criteria for drug-induced liver injury (DILI) used in the clinical studies and related literature in China are very confusing, making it difficult to compare and extend the use of the results, conclusions, and experience of these studies. Therefore, it is necessary to carefully review the developmental history of diagnostic scales and unify the diagnostic criteria and related knowledge of DILI. Since its publication in 1993, Roussel Uclaf Causality Assessment Method (RUCAM) scale has been widely used to assess the causality between drugs and liver injury, both in DILI studies and decisions on the regulation of drugs which may cause liver injury, in order to provide a useful analytical framework for clinical physicians in the diagnosis of DILI. At present, RUCAM scale should still be used to assess causality and assist diagnosis, unless markers with diagnostic significance are found in future.

Tenofovir disoproxil fumarate vs adefovir dipivoxil in Chinese patients with chronic hepatitis B after 48 weeks: a randomized controlled trial

Tenofovir disoproxil fumarate (TDF) has demonstrated long-term efficacy and a high barrier to resistance in multiple chronic hepatitis B (CHB) populations outside of China. This study aimed to evaluate the efficacy and safety of TDF compared with adefovir dipivoxil (ADV) in Chinese patients with CHB during 48 weeks of treatment (ClinicalTrial.gov number, NCT01300234). A Phase 3, multicentred, randomized, double-blind, controlled trial compared the efficacy and safety of TDF with ADV in Chinese patients with CHB. The primary endpoint was the proportion of patients with HBV DNA <400 copies/mL in each treatment group at Week 48, using an unpooled Z-test for superiority. Secondary endpoints included viral suppression, serologic response, histological improvement, normalization of alanine aminotransferase (ALT) levels and the emergence of resistance mutations. A total of 509 patients, 202 hepatitis B e antigen (HBeAg)-positive and 307 HBeAg-negative, with HBV DNA ≥10(5) copies/mL received either TDF 300 mg od or ADV 10 mg od. At Week 48, TDF demonstrated superior viral suppression compared with ADV in both HBeAg-positive (76.7% vs 18.2%, P < 0.0001) and HBeAg-negative (96.8% vs 71.2%, P < 0.0001) patients. The majority of patients in both treatment arms achieved ALT normalization (>85%). No resistance to TDF was observed. The frequency of adverse events was comparable between treatment arms (TDF 3.9% vs ADV 4.8%). In this double-blind, randomized, clinical trial, TDF demonstrated superiority over ADV with respect to viral suppression in Chinese patients with CHB at 48 weeks of treatment and without the development of resistance.

Oral toxicity evaluation of kefir-isolated Lactobacillus kefiranofaciens M1 in Sprague-Dawley rats

Lactobacilli kefiranofaciens M1 has shown novel immunomodulation and anti-allergy probiotic attributes in cell and animal models. An acute oral toxicity assessment of L. kefiranofaciens M1 was evaluated in Sprague-Dawley rats. The rats were randomly assigned to four groups (12 rats/sex/group): the low dose group was orally gavaged with L. kefiranofaciens M1 at 3.0×10(8)cfu/kg bw while the medium dose and high dose groups received 9.0×10(9)cfu/kg bw and 1.8×10(10)cfu/kg bw, respectively, for 28days. The control group received phosphate buffer saline. The body weights were measured weekly while blood samples were collected for haematology and serum biochemistry tests. Histopathology of the organs (heart, liver, kidney, adrenal glands, spleen, ovary, testis), and urinalysis were conducted on study termination. The body weight gain of the L. kefiranofaciens M1 and control groups were comparable during the administration period. Overall, L. kefiranofaciens M1 did not induce adverse effects on haematology, serum biochemistry, and urinalysis parameters. Gross and microscopic histopathology of the organs revealed no toxicity effect of L. kefiranofaciens M1. In conclusion, 1.8×10(10)cfu/kg bw of L. kefiranofaciens M1 was considered as the no-observed-adverse-effect-level (NOAEL), which was the highest dose tested in the present study.

Two years efficiency of lamivudine and adefovir dipivoxil combined therapy in chronic hepatitis B patients

BACKGROUND

Lamivudine (LAM) and adefovir (ADV) are widely used in most Asian countries, though monotherapy is associated with the occurrence of resistance.

AIM

To evaluate the efficiency of LAM and ADV combined treatment of chronic hepatitis B patients with compensated cirrhosis.

PATIENTS AND METHODS

206 eligible Chinese patients were randomly assigned in a 1:1 ratio to receive either LAM or ADV for the first 24 weeks. According to virologic response at 24 weeks, the patients either continued to monotherapy or switched to combined therapy for 48 weeks. After 48 weeks, all patients received LAM and ADV combined therapy for 96 weeks.

RESULTS

Serum HBV DNA levels significantly decreased in patients with ADV or LAM monotherapy and continuously reduced after the combined therapy. Serum ALT normalized rate were 88.24% and 81.37% at week 48, and 95.74% and 87.36% at week 96 in ADV and LAM group respectively, comparing to 60.78% and 56.73% in ADV and LAM groups at baseline. The accumulated virological breakthrough rate at week 48 and 96 was significantly higher in LAM group.

CONCLUSIONS

Both combination strategies were resulted in the long term virological, biochemical improvement in Chinese chronic hepatitis B patients with compensated cirrhosis.

Influence of different flow-triggering levels on the breathing effort of mechanically ventilated patients

BACKGROUND

Although a sensitive flow triggering (FT) level is supposed to be associated with reduced breathing effort, the incidence of autotriggering (AT) is likely to be increased. The actual effects of various FT levels on the work of breathing and occurrence of AT in mechanically ventilated patients are unknown. We investigated the effects of different FT levels (1-8 L/min) on breathing effort and incidence of AT in mechanically ventilated patients under pressure support ventilation using a Puritan-Bennett 840 ventilator.

METHODS

Eight FT levels were randomly studied in mechanically ventilated patients under pressure support ventilation. The triggering effort (pressure-time product of triggering, PTPtr) was assessed by quantitating a segment of the pressure-time product of the esophagus (PTPes). The total PTPes, inspiratory work of breathing (Wi) and P0.1 were determined.

RESULTS

Nine patients with appropriately recorded signals were included. The incidence of AT significantly decreased with increasing FT level (FT1, 1 L/min: 30.7%, FT8: 0.2%). PTPtr significantly increased with increasing FT level (0.020 ± 0.004 cmH2O • S in FT1 to 0.190 ± 0.017 cmH2O • S in FT8), but P0.1 remained similar. PTPtr accounted for only1-3% of total PTPes. Wi and PTPes were significantly lower only at FT1, but there was no significant difference in Wi and PTPes at different FT levels when AT breaths were excluded.

CONCLUSION

A higher FT level was associated with lower incidence of AT, but without a significant increase in breathing effort. A higher FT level may be more reasonable in mechanically ventilated patients with this particular ventilator.

Transport behavior and negative magnetoresistance in chemically reduced graphene oxide nanofilms

The electron transport behavior in chemically reduced graphene oxide (rGO) sheets with different thicknesses of 2, 3, and 5 nm was investigated. The four-probe method for the sheet resistance (R(S)) measurement on the intensively reduced graphene oxide samples indicates an Arrhenius characteristic of the electron transport at zero magnetic field B = 0, consistent with previous experimental results on well-reduced GO samples. The anticipated variable range hopping (VRH) transport of electrons in a two-dimensional electron system at low temperatures was not observed. The measured R(S) of the rGO samples are below 52 kΩ/square at room temperature. With the application of a magnetic field up to 4 T, negative magnetoresistance in the Mott VRH regime was observed. The magnetotransport features support a model based on the spin-coupling effect from the vacancy-induced midgap states that facilitate the Mott VRH conduction in the presence of an external magnetic field.

A retrospective study of pulmonary infarction in patients with systemic lupus erythematosus from southern Taiwan

Since large-scale reports of pulmonary infarction in systemic lupus erythematosus (SLE) are limited, a retrospective study was performed for this manifestation in 773 hospitalized patients in southern Taiwan from 1999 to 2009. Pulmonary infarction was defined as the presence of pulmonary embolism, persistent pulmonary infiltrates, and characteristic clinical symptoms. Demographic, clinical, laboratory, and radiological images data were analyzed. There were 12 patients with pulmonary embolism and 9 of them had antiphospholipid syndrome (APS). Six patients (19 to 53 years, average 38.2 ± 12.6) with 9 episodes of lung infarction were identified. All cases were APS and four episodes had coincidental venous thromboembolism. There were four episodes of bilateral infarction and seven episodes of larger central pulmonary artery embolism. Heparin therapy was routinely prescribed and thrombolytic agents were added in two episodes. Successful recovery was noted in all patients. In conclusion, there was a 0.8% incidence of pulmonary infarction in patients with SLE, all with the risk factor of APS. Differentiation between pulmonary infarction and pneumonia in lupus patients should be made; they have similar chest radiography with lung consolidation but require a different clinical approach in management. Although this report is a retrospective study with relatively small numbers of lupus patients with lung infarcts, our observation might provide beneficial information on the clinical features and radiological presentations during the disease evolution of pulmonary infarction in SLE with APS.

Properties of Tetrahedral Amorphous Carbon Deposited by A Filtered Cathodic Vacuum ARC

The properties of a highly sp3 bonded form of amorphous carbon denoted ta-C deposited from a filtered cathodic vacuum arc (FCVA) are described as a function of ion energy and deposition temperature. The sp3 fraction depends strongly on ion energy and reaches 85% at an ion energy of 100 eV. Other properties such as density and band gap vary in a similar fashion, with the optical gap reaching a maximum of 2.3 eV. These films are very smooth with area roughness of order 1 nm. The sp3 fraction falls suddenly to almost zero for deposition above about 200°C.

Electronic Structure and Surface Properties of SrBi2Ta2O9 and Related Oxides

The electronic structure of SrBi2Ta2O9 and related oxides such as SrBi2Nb2O9, Bi2WO6 and Bi3Ti4O12 have been calculated by the tight-binding method. In each case, the band gap is about 4.1 eV and the band edge states occur on the Bi-O layers and consist of mixed O p/Bi s states at the top of the valence band and Bi p states at the bottom of the conduction band. The main difference between the compounds is that Nb 5d and Ti 4d states in the Nb and Ti compounds lie lower than the Ta 6d states in the conduction band. The surface pinning levels are found to pin Schottky barriers 0.8 eV below the conduction band edge.

Doping Mechanism in Tetrahedral Amorphous Carbon

Doping in hydrogenated amorphous silicon occurs by a process of an ionised donor atom partially compensated by a charged dangling bond. The total energies of various dopant and dopant/bonding combinations are calculated for tetrahedral amorphous carbon. It is found that charged dangling bonds are less favoured because of the stronger Coulombic repulsion in ta-C. Instead the dopants can be compensated by weak bond states in the lower gap associated with odd-membered π-rings or odd-numbered π-chains. The effect is that the doping efficiency is low but there are not charged midgap recombination centres, to reduce photoconductivity or photoluminescence with doping, as occurs in a-Si:H.

Virological, serological and biochemical outcomes through 3 years of entecavir treatment in nucleoside-naive Chinese chronic hepatitis B patients

Hepatitis B virus (HBV) infection has a high prevalence in China. Entecavir has shown superior efficacy over lamivudine in Chinese nucleoside-naive chronic hepatitis B (CHB) patients over 48 weeks, with continued clinical benefit to 96 weeks. The present study evaluates the long-term efficacy of entecavir in Chinese CHB patients who continued entecavir treatment for 144 weeks. Patients receiving either entecavir 0.5 mg/day (n = 258) or lamivudine 100 mg/day (n = 261) entered the initial 96-week randomized, double-blind, controlled efficacy study. Patients who did not achieve a consolidated response [HBV DNA <0.7 MEq/mL; alanine aminotransferase (ALT) <1.25 x upper limit of normal; and if hepatitis B e antigen (HBeAg) positive at baseline, loss of HBeAg for ≥ 24 weeks] or who experienced viral breakthrough or relapse entered a 48-week entecavir rollover study. A total of 160 patients received continuous entecavir for 144 weeks; of these, 89% had undetectable serum HBV DNA, 86% showed ALT normalization, 20% reported HBeAg loss and 8% experienced HBeAg seroconversion. The cumulative rates of HBeAg loss and seroconversion were 36% and 27% at Week 144, respectively. The development of resistance was low, with three patients up to Week 96 and an additional two patients in Weeks 96-144 showing evidence of associated genotypic mutations. Entecavir was well tolerated. Adverse event rates were similar to those in lamivudine-treated patients, but patients receiving entecavir experienced fewer ALT flares. This study demonstrates that entecavir provides durable, long-term suppression of HBV DNA and ALT normalization in Chinese CHB patients, and is associated with low rates of emerging resistance. The results are consistent with the findings using entecavir globally and in Japan.

Constructed wetland for water quality improvement: a case study from Taiwan

In Taiwan, more than 20% of the major rivers are mildly to heavily polluted by domestic, industrial, and agricultural wastewaters due to the low percentage of sewers connected to wastewater treatment plants. Thus, constructed or engineered wetlands have been adopted as the major alternatives to clean up polluted rivers. Constructed wetlands are also applied as the tertiary wastewater treatment systems for the wastewater polishment to meet water reuse standards with lower operational costs. The studied Kaoping River Rail Bridge Constructed Wetland (KRRBCW) is the largest constructed wetland in Taiwan. It is a multi-function wetland and is used for polluted creek water purification and secondary wastewater polishment before it is discharged into the Kaoping River. Although constructed wetlands are feasible for contaminated water treatment, wetland sediments are usually the sinks for organics and metals. In this study, water and sediment samples were collected from the major wetland basins in KRRBCW. The investigation results show that more than 97% of total coliforms (TC), 55% of biochemical oxygen demand (BOD), and 30% of nutrients [e.g. total nitrogen (TN), total phosphorus (TP)] were removed via the constructed wetland system. However, results from the sediment analyses show that wetland sediments contained high concentrations of metals (e.g. Cu, Fe, Zn, Cr, and Mn), organic contents (sediment oxygen demand = 1.7 to 7.6 g O(2)/m(2) d), and nutrients (up to 18.7 g/kg of TN and 1.22 g/kg of TN). Thus, sediments should be excavated periodically to prevent the release the pollutants into the wetland system and causing the deterioration of wetland water quality. Results of polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and nucleotide sequence analysis reveal that a variation in microbial diversity in the wetland systems was observed. Results from the DGGE analysis indicate that all sediment samples contained significant amounts of microbial ribospecies, which might contribute to the carbon degradation and nitrogen removal. Gradual disappearance of E. coli was also observed along the flow courses through natural attenuation mechanisms.

Using a constructed wetland for non-point source pollution control and river water quality purification: a case study in Taiwan

The Kaoping River Rail Bridge Constructed Wetland, which was commissioned in 2004, is one of the largest constructed wetlands in Taiwan. This multi-function wetland has been designed for the purposes of non-point source (NPS) pollutant removal, wastewater treatment, wildlife habitat, recreation, and education. The major influents of this wetland came from the local drainage trench containing domestic, agricultural, and industrial wastewaters, and effluents from the wastewater treatment plant of a paper mill. Based on the quarterly investigation results from 2007 to 2009, more than 96% of total coliforms (TC), 48% of biochemical oxygen demand (BOD), and 40% of nutrients (e.g. total nitrogen, total phosphorus) were removed via the constructed wetland system. Thus, the wetland system has a significant effect on water quality improvement and is capable of removing most of the pollutants from the local drainage system before they are discharged into the downgradient water body. Other accomplishments of this constructed wetland system include the following: providing more green areas along the riversides, offering more water assessable eco-ponds and eco-gardens for the public, and rehabilitating the natural ecosystem. The Kaoping River Rail Bridge Constructed Wetland has become one of the most successful multi-function constructed wetlands in Taiwan. The experience obtained from this study will be helpful in designing similar natural treatment systems for river water quality improvement and wastewater treatment.

Enhancement of random lasing based on the composite consisting of nanospheres embedded in nanorods template

A simple and general approach has been developed for the enhancement of random lasing based on the composite consisting of nanospheres and nanorods array. Due to the inherent nature of high refractive index, the selected nanorods act efficiently as scattering feedback centers, which can promote the formation of closed loop paths of the emission arising from nanospheres. To illustrate our working principle, the composite consisting of Tb(OH)(3)/SiO(2) nanospheres and ZnO nanorods was chosen as an example. Quite interestingly, it is found that the random lasing behavior can be easily achieved for the composite system, while it is absent in pure Tb(OH)(3)/SiO(2) nanospheres. The strategy demonstrated here should be very useful for the future development of coherent light emission sources and many other optoelectronic devices.

Evaluation of biological stability and corrosion potential in drinking water distribution systems: a case study

The appearance of assimilable organic carbon (AOC), microbial regrowth, disinfection by-products (DBPs), and pipe corrosion in drinking water distribution systems are among those major safe drinking water issues in many countries. The water distribution system of Cheng-Ching Lake Water Treatment Plant (CCLWTP) was selected in this study to evaluate the: (1) fate and transport of AOC, DBPs [e.g., trihalomethanes (THMs), haloacetic acids (HAAs)], and other organic carbon indicators in the selected distribution system, (2) correlations between AOC (or DBPs) and major water quality parameters [e.g. dissolved oxygen (DO), free residual chlorine, and bacteria, and (3) causes and significance of corrosion problems of the water pipes in this system. In this study, seasonal water samples were collected from 13 representative locations in the distribution system for analyses of AOC, DBPs, and other water quality indicators. Results indicate that residual free chlorine concentrations in the distribution system met the drinking water standards (0.2 to 1 mg l(-1)) established by Taiwan Environmental Protection Administration (TEPA). Results show that AOC measurements correlated positively with total organic carbon (TOC) and UV-254 (an organic indicator) values in this system. Moreover, AOC concentrations at some locations were higher than the 50 microg acetate-C l(-1) standard established by Taiwan Water Company. This indicates that the microbial regrowth might be a potential water quality problem in this system. Higher DO measurements (>5.7 mg l(-1)) might cause the aerobic biodegradation of THMs and HAAs in the system, and thus, low THMs (<0.035 mg l(-1)) and HAAs (<0.019 mg l(-1)) concentrations were observed at all sampling locations. Results from the observed negative Langelier Saturation Index (LSI) values, higher Ryznar Stability Index (RSI) values, and high Fe3+ concentrations at some pipe-end locations indicate that highly oxidative and corrosive conditions occurred. This reveals that pipe replacement should be considered at these locations. These findings would be helpful in managing the water distribution system for maintaining a safe drinking water quality.

Spectroscopic studies of solvothermally derived LaF3:Nd nanocrystals

LaF3:Nd (0.5-10.7 mol%) nanocrystals were solvothermally synthesized and their optical properties were studied. Judd-Ofelt parameterization of the absorption spectra gave a radiative decay time of 846 micros for the 4F3/2 excited state to the four emission channels. Measured fluorescence decay curves for 5 different Nd3+ concentrations were fit with double exponential functions. The decrease in fluorescence decay time shows that concentration quenching is appreciable as the Nd3+ concentration increases. The 0.5 mol% Nd3+ concentration shows a decay time of 800 micros and a radiative quantum efficiency of 95%. For all dopant concentrations, heat-treatment (800 degrees C, 2 h) substantially increased the emission intensity by 2 to 3-orders of magnitude. This emission intensity increase is attributed to reduction in hydroxyls and homogenization of the Nd3+ coordination environment through improved crystalline perfection of the LaF3:Nd lattice.