In vivo assessment of dual-function submicron textured nitric oxide releasing catheters in a 7-day rabbit model.

Catheter-induced thrombosis is a major contributor to infectious and mechanical complications of biomaterials that lead to device failure. Herein, a dualfunction submicron textured nitric oxide (NO)-releasing catheter was developed. The hemocompatibility and antithrombotic activity of vascular catheters were evaluated in both 20 h in vitro blood loop and 7 d in vivo rabbit model. Surface characterization assessments via atomic force microscopy show the durability of the submicron pattern after incorporation of NO donor S-nitroso-N-acetylpenicillamine (SNAP). The SNAP-doped catheters exhibited prolonged and controlled NO release mimicking the levels released by endothelium. Fabricated catheters showed cytocompatibility when evaluated against BJ human fibroblast cell lines. After 20h in vitro evaluation of catheters in a blood loop, textured-NO catheters exhibited a 13-times reduction in surface thrombus formation compared to the control catheters, which had 83% of the total area covered by clots. After the 7 d in vivo rabbit model, analysis on the catheter surface was examined via scanning electron microscopy, where significant reduction of platelet adhesion, fibrin mesh, and thrombi can be observed on the NO-releasing textured surfaces. Moreover, compared to relative controls, a 63% reduction in the degree of thrombus formation within the jugular vein was observed. Decreased levels of fibrotic tissue decomposition on the jugular vein and reduced platelet adhesion and thrombus formation on the texture of the NO-releasing catheter surface are indications of mitigated foreign body response. This study demonstrated a biocompatible and robust dual-functioning textured NO PU catheter in limiting fouling-induced complications for longer-term blood-contacting device applications. STATEMENT OF SIGNIFICANCE: Catheter-induced thrombosis is a major contributor to infectious and mechanical complications of biomaterials that lead to device failure. This study demonstrated a robust, biocompatible, dual-functioning textured nitric oxide (NO) polyurethane catheter in limiting fouling-induced complications for longer-term blood-contacting device applications. The fabricated catheters exhibited prolonged and controlled NO release that mimics endothelium levels. After the 7 d in vivo model, a significant reduction in platelet adhesion, fibrin mesh, and thrombi was observed on the NO-releasing textured catheters, along with decreased levels of fibrotic tissue decomposition on the jugular vein. Results illustrate that NO-textured catheter surface mitigates foreign body response.

In Vitro and In Vivo Assessment of the Infection Resistance and Biocompatibility of Small-Molecule-Modified Polyurethane Biomaterials.

Bacterial intracellular nucleotide second messenger signaling is involved in biofilm formation and regulates biofilm development. Interference with the bacterial nucleotide second messenger signaling provides a novel approach to control biofilm formation and limit microbial infection in medical devices. In this study, we tethered small-molecule derivatives of 4-arylazo-3,5-diamino-1H-pyrazole on polyurethane biomaterial surfaces and measured the biofilm resistance and initial biocompatibility of modified biomaterials in in vitro and in vivo settings. Results showed that small-molecule-modified surfaces significantly reduced the Staphylococcal epidermidis biofilm formation compared to unmodified surfaces and decreased the nucleotide levels of c-di-AMP in biofilm cells, suggesting that the tethered small molecules interfere with intracellular nucleotide signaling and inhibit biofilm formation. The hemocompatibility assay showed that the modified polyurethane films did not induce platelet activation or red blood cell hemolysis but significantly reduced plasma coagulation and platelet adhesion. The cytocompatibility assay with fibroblast cells showed that small-molecule-modified surfaces were noncytotoxic and cells appeared to be proliferating and growing on modified surfaces. In a 7-day subcutaneous infection rat model, the polymer samples were implanted in Wistar rats and inoculated with bacteria or PBS. Results show that modified polyurethane significantly reduced bacteria by ∼2.5 log units over unmodified films, and the modified polymers did not lead to additional irritation/toxicity to the animal tissues. Taken together, the results demonstrated that small molecules tethered on polymer surfaces remain active, and the modified polymers are biocompatible and resistant to microbial infection in vitro and in vivo.

Application of improved GalNAc conjugation in development of cost-effective siRNA therapies targeting cardiovascular diseases.

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.

Current Medicare reimbursement for complex endovascular aortic repair is inadequate based on results from a multi-institutional cost analysis.

OBJECTIVE: Complex endovascular juxta-, para- and suprarenal abdominal aortic aneurysm repair (comEVAR) is frequently accomplished with commercially available fenestrated (FEVAR) devices or off-label use of aortoiliac devices with parallel branch stents (chEVAR). We sought to evaluate the implantable vascular device costs incurred with these procedures as compared with standard Medicare reimbursement to determine the financial viability of comEVAR in the modern era. METHODS: Five geographically distinct institutions with high-volume, complex aortic centers were included. Implantable aortoiliac and branch stent device cost data from 25 consecutive, recent, comEVAR in the treatment of juxta-, para-, and suprarenal aortic aneurysms at each center were analyzed. Cases of rupture, thoracic aneurysms, reinterventions, and physician-modified EVAR were excluded, as were ancillary costs from nonimplantable equipment. Data from all institutions were combined and stratified into an overall cost group and two, individual cost groups: FEVAR or chEVAR. These groups were compared, and each respective group was then compared with weighted Medicare reimbursement for Diagnosis-Related Group codes 268/269. Median device costs were obtained from an independent purchasing consortium of >3000 medical centers, yielding true median cost-to-institution data rather than speculative, administrative projections or estimates. RESULTS: A total of 125 cases were analyzed: 70 FEVAR and 53 chEVAR. Two cases of combined FEVAR/chEVAR were included in total cost analysis, but excluded from direct FEVAR vs chEVAR comparison. Median Medicare reimbursement was calculated as $35,755 per case. Combined average implantable device cost for all analyzed cases was $28,470 per case, or 80% of the median reimbursement ($28,470/$35,755). Average FEVAR device cost per case ($26,499) was significantly lower than average chEVAR cost per case ($32,122; P < .002). Device cost was 74% ($26,499/$35,755) of total reimbursement for FEVAR and 90% ($32,122/$35,755) for chEVAR. CONCLUSIONS: Results from this multi-institutional analysis show that implantable device cost alone represents the vast majority of weighted total Medicare reimbursement per case with comEVAR, and that chEVAR is significantly more costly than FEVAR. Inadequate Medicare reimbursement for these cases puts high-volume, high-complexity aortic centers at a distinct financial disadvantage. In the interest of optimizing patient care, these data suggest a reconsideration of previously established, outdated, Diagnosis-Related Group coding and Medicare reimbursement for comEVAR.

[Temporal and Spatial Characteristics of Net CO2 Emissions and Decoupling Analysis in Yangtze River Economic Belt].

Calculating the fossil energy consumption, revealing the temporal and spatial evolution characteristics of net CO2 emissions, and analyzing the decoupling effect between social development and net CO2 emissions in different regions of the Yangtze River Economic Belt (YREB) is crucial to support the different regions, allowing them to select their individual industrial development and carbon emission reduction path. The results showed that:① from 1999 to 2012, YREB became greener, the CO2 emission of the YREB increased by 2244.23 million tons, and the carbon sink increased by 148.07 million tons during the research period. ② From 2013 to 2018, the area of medium-high carbon sequestration (NPP>800 g·m-2, count for C) increased by 23.25%, compared with that from 1999-2012. ③ A highly decoupling effect between social development and net CO2 emissions was found in the downstream of the YREB. The highest decoupling cities in the upstream, midstream, and downstream accounted for 12%, 34%, and 54% of the highest decoupling cities in the YREB, respectively.

Lessons from COVID-19 pandemic: Analysis of unequal access to food stores using the Gini coefficient.

COVID-19 has dramatically altered daily life worldwide, with some urban residents resorting to panic buying at the beginning of the pandemic. Large-scale lockdowns and restaurant closures have increased the need for grocery shopping. Such shifts in consumer patterns have altered supply-demand systems. Insufficient food store availability increases the likelihood of crowding and thus increases the probability of viral infection. People who live without easy access to food stores also face high infection risks when forced to travel long distances for grocery shopping. The COVID-19 pandemic has demonstrated the importance of the number and distribution of food stores to virus transmission. Food access is also a core factor of urban resilience during the pandemic. This study used the Gini coefficient to investigate the fairness of accessibility to food stores at the city and village levels, with Taipei City chosen as the research area. Different spatial scales were considered, and we calculated the equality of food access for older (≥65 years old) and non-older populations separately to determine whether one group faces greater inequality. At the city level, both older and non-older populations in Taipei have reasonable access (Gini coefficient between 0.3 and 0.4), with mean Gini coefficients of 0.3616 and 0.3655, respectively. This city-level analysis represents the overall degree of unequal access to food stores. At the village level, eight villages (1.8 %; total N = 456) had severe access inequality (Gini coefficient > 0.6) for older adults; they are located primarily in downtown or suburban areas. For the non-older population, only two villages (0.4 %; total N = 456) in suburban areas exhibit severe access inequality. The village-level analysis identified villages with low equality of access to food stores and revealed local problems that cannot be observed at the city level.

Comparison of three cognitive assessment methods in post-stroke aphasia patients.

Background: The cognitive level of post-stroke aphasia (PSA) patients is generally lower than non-aphasia patients, and cognitive impairment (CI) affects the outcome of stroke. However, for different types of PSA, what kind of cognitive assessment methods to choose is not completely clear. We investigated the Montreal Cognitive Assessment (MoCA), the Mini-Mental State Examination (MMSE), and the Non-language-based Cognitive Assessment (NLCA) to observe the evaluation effect of CI in patients with fluent aphasia (FA) and non-fluent aphasia (NFA). Methods: 92 stroke patients were included in this study. Demographic and clinical data of the stroke group were documented. The language and cognition were evaluated by Western Aphasia Battery (WAB), MoCA, MMSE, and NLCA. PSA were divided into FA and NFA according to the Chinese aphasia fluency characteristic scale. Pearson's product-moment correlation coefficient test and multiple linear regression analysis were performed to explore the relationship between the sub-items of WAB and cognitive scores. The classification rate of CI was tested by Pearson's Chi-square test or Fisher's exact test. Results: The scores of aphasia quotient (AQ), MoCA, MMSE, and NLCA in NFA were lower than FA. AQ was positively correlated with MoCA, MMSE, and NLCA scores. Stepwise multiple linear regression analysis suggested that naming explained 70.7% of variance of MoCA and 79.9% of variance of MMSE; comprehension explained 46.7% of variance of NLCA. In the same type of PSA, there was no significant difference in the classification rate. The classification rate of CI in NFA by MoCA and MMSE was higher than that in FA. There was no significant difference in the classification rate of CI between FA and NFA by NLCA. Conclusion: MoCA, MMSE, and NLCA can be applied in FA. NLCA is recommended for NFA.

A Novel Automated RGB-D Sensor-Based Measurement of Voluntary Items of the Fugl-Meyer Assessment for Upper Extremity: A Feasibility Study.

Motor function assessment is essential for post-stroke rehabilitation, while the requirement for professional therapists' participation in current clinical assessment limits its availability to most patients. By means of sensors that collect the motion data and algorithms that conduct assessment based on such data, an automated system can be built to optimize the assessment process, benefiting both patients and therapists. To this end, this paper proposed an automated Fugl-Meyer Assessment (FMA) upper extremity system covering all 30 voluntary items of the scale. RGBD sensors, together with force sensing resistor sensors were used to collect the patients' motion information. Meanwhile, both machine learning and rule-based logic classification were jointly employed for assessment scoring. Clinical validation on 20 hemiparetic stroke patients suggests that this system is able to generate reliable FMA scores. There is an extremely high correlation coefficient (r = 0.981, p < 0.01) with that yielded by an experienced therapist. This study offers guidance and feasible solutions to a complete and independent automated assessment system.

Systematic assessment of the development and recovery characteristics of hydrological drought in a semi-arid area.

Studies have documented the significant effect of various factors on hydrological drought events. However, few studies have quantified drought's development and recovery process under environmental changes. This study focused on identifying hydrological drought's development and recovery characteristics and their potential causes in a typical semi-arid area. The Standardized Streamflow Index (SSI) was used as a metric for hydrological droughts, while the run theory was applied to identify the development and recovery processes of droughts. Changes in observed (human disturbed scenario) and simulated (natural scenario) droughts by employing the SWAT (Soil and Water Assessment Tool) model were also investigated from 1970 to 2016. The "simulated-observed" approach was used to assess the impacts of human regulations on hydrological drought development and recovery characteristics. Results showed that hydrological droughts occurred mainly during 1980-1990 and 2000-2016. In the natural condition, drought duration and intensity were higher, while lower severity in the drought recovery stage than development stage was observed. The drainage characteristics of the basin played the most critical role in the development and recovery characteristics of drought, which were also influenced by climatic conditions. Human activities had exacerbated recent natural hydrological drought. When considering the contribution of human activities, the reservoir operation was the dominant anthropic factor affected the development and recovery process of drought in the study area. Under the effects of reservoir regulation, long-duration hydrological droughts became rare. Moreover, the recovery ability of drought had been weakened. The effects of the reservoir were progressively crucial gradually. Although the water got from the river by the reservoir had been reduced, the negative impact on aggravating drought remains stronger than the reservoir was initially constructed. The results of our study will help improve the optimal management of reservoirs in semi-arid areas and enhance drought early warning and forecasting system.

Life-cycle assessment of two sewage sludge-to-energy systems based on different sewage sludge characteristics: Energy balance and greenhouse gas-emission footprint analysis.

Anaerobic digestion and incineration are widely used sewage sludge (SS) treatment and disposal approaches to recovering energy from SS, but it is difficult to select a suitable technical process from the various technologies. In this study, life-cycle assessments were adopted to compare the energy- and greenhouse gas- (GHG) emission footprints of two sludge-to-energy systems. One system uses a combination of AD with incineration (the AI system), whereas the other was simplified by direct incineration (the DI system). Comparison between three SS feedstocks (VS/TS: 57.61 -73.1 ds.%) revealed that the AI system consistently outperformed the DI system. The results of sensitivity analyses showed that the energy and GHG emission performances were mainly affected by VS content of the SS, AD conversion efficiency, and the energy consumption of sludge drying. Furthermore, the energy and GHG emission credit of the two systems increased remarkably with the increase in the VS content of the SS. For the high-organic-content sludge (VS/TS: 55%-80%), the energy and GHG emission credit of the AI system increase with the increase of AD conversion efficiency. However, for the low organic content sludge (VS/TS: 30%-55%), it has the opposite effect. In terms of energy efficiency and GHG performance, the AI system is a good choice for the treatment of high-organic-content sludge (VS/TS>55%), but DI shows superiority over AI when dealing with low organic content sludge (VS/TS<55%).

A cross-sectional study: an assessment of low muscle mass and osteoporosis in type 2 diabetes mellitus patients with a high glycated hemoglobin level.

BACKGROUND: Low muscle mass and osteoporosis are commonly observed in individuals with type 2 diabetes mellitus (T2DM). We investigated the prevalence of low muscle mass and osteoporosis in patients with T2DM who had high glycated hemoglobin (HbA1c) levels. METHODS: We included 187 Chinese patients with T2DM who were aged ⩾50 years and evaluated their body composition using dual-energy X-ray absorptiometry. We measured levels of fasting blood glucose, HbA1c, B collagen-specific sequences (B-CTX), osteocalcin (OC), propeptide of type 1 procollagen (P1NP), and 25-hydroxy vitamin D. RESULTS: Of the total patients, 82 were men and 105 were women. The prevalence rates of low muscle mass, osteopenia, and osteoporosis were 35.8%, 38.0%, and 31.0%, respectively. The prevalence rate of low muscle mass was significantly higher in women with HbA1c levels >9.0% than in those with HbA1c levels <9.0%. The prevalence rates of osteopenia and osteoporosis in men with HbA1c levels >9.0% differed significantly from those with HbA1c levels <9.0%. The appendicular skeletal muscle mass index (ASMI), trunk muscle mass, lumbar spinal bone mineral content (BMC), lumbar spine BMD, femoral BMC, and femoral BMD were significantly decreased, and the serum levels of B-CTX, OC, and P1NP were significantly increased in patients with T2DM who had osteoporosis. The ASMI was associated with osteopenia/osteoporosis in men and women with T2DM. CONCLUSIONS: In patients with T2DM, high HbA1c levels were associated with higher prevalence rates of low muscle mass in women and osteoporosis in men, and ASMI was a risk factor of osteoporosis.

Isolation of a Highly Efficient Antigenic-Protein-Degrading Bacillus amyloliquefaciens and Assessment of Its Safety.

The aims of this study were to screen and isolate a highly efficient strain from the rumen of a cow that can degrade the antigenic soy proteins in soybean meal (SBM) and improve the nutritional value of SBM by fermenting it with this strain. The safety of this strain was investigated with an acute oral toxicity test. A Bacillus amyloliquefaciens strain was successfully screened with plate tests and fermentation. After solid state fermentation of SBM with B. amyloliquefaciens for 24 h, the amounts of glycinin and ß-conglycinin, two major antigenic proteins in SBM, decreased by 92.32% and 85.05%, respectively. The crude protein content in the fermented soybean meal (FSBM) increased by 17.54% compared with that in SBM. Notably, the trichloroacetic-acid-soluble protein (TCA-SP) content, particularly small peptides and free amino acids, was 9.97-fold higher in FSBM than in SBM. The in vitro dry matter digestibility and digestible energy of SBM increased from 62.91% to 72.52% and from 10.42 MJ/kg to 13.37 MJ/kg (dry matter basis), respectively, after fermentation. The acute oral toxicity test suggested that the strain exerted no harmful effects on the relative organ weights, the morphological tissue structure, or the health of mice. These results indicate that the B. amyloliquefaciens strain isolated in this study is a safe strain for animals, and could be used to improve the nutritional quality of SBM by solid-state fermentation.

Quantitative Assessment of Motor Function for Patients with a Stroke by an End-Effector Upper Limb Rehabilitation Robot.

With the popularization of rehabilitation robots, it is necessary to develop quantitative motor function assessment methods for patients with a stroke. To make the assessment equipment easier to use in clinics and combine the assessment methods with the rehabilitation training process, this paper proposes an anthropomorphic rehabilitation robot based on the basic movement patterns of the upper limb, point-to-point reaching and circle drawing movement. This paper analyzes patients' movement characteristics in aspects of movement range, movement accuracy, and movement smoothness and the output force characteristics by involving 8 patients. Besides, a quantitative assessment method is also proposed based on multivariate fitting methods. It can be concluded that the area of the real trajectory and movement accuracy during circle drawing movement as well as the ratio of force along the sagittal axis in backward point-to-point movement are the unique parameters that are different remarkably between stroke patients and healthy subjects. The fitting function has a high goodness of fit with the Fugl-Meyer scores for the upper limb (R 2 = 0.91, p = 0.015), which demonstrates that the fitting function can be used to assess patients' upper limb movement function. The indicators are recorded during training movement, and the fitting function can calculate the scores immediately, which makes the functional assessment quantitative and timely. Combining the training process and assessment, the quantitative assessment method will farther expand the application of rehabilitation robots.

Rapid Solution-Phase Hydrogen/Deuterium Exchange for Metabolite Compound Identification.

Rapid, solution-phase hydrogen/deuterium exchange (HDX) coupled with mass spectrometry (MS) is demonstrated as a means for distinguishing small-molecule metabolites. HDX is achieved using capillary vibrating sharp-edge spray ionization (cVSSI) to allow sufficient time for reagent mixing and exchange in micrometer-sized droplets. Different compounds are observed to incorporate deuterium with varying efficiencies resulting in unique isotopic patterns as revealed in the MS spectra. Using linear regression techniques, parameters representing contribution to exchange by different hydrogen types can be computed. In this proof-of-concept study, the exchange parameters are shown to be useful in the retrodiction of the amount of deuterium incorporated within different compounds. On average, the exchange parameters retrodict the exchange level with ~ 2.2-fold greater accuracy than treating all exchangeable hydrogens equally. The parameters can be used to produce hypothetical isotopic distributions that agree (± 16% RMSD) with experimental measurements. These initial studies are discussed in light of their potential value for identifying challenging metabolite species.

A Low-Cost Electromagnetic Docking Guidance System for Micro Autonomous Underwater Vehicles.

As important observational platforms for the Smart Ocean concept, autonomous underwater vehicles (AUVs) that perform long-term observation in fleets are beneficial because they provide large-scale sampling data with a sufficient spatiotemporal resolution. Therefore, a large number of low-cost micro AUVs with docking capability for power recharge and data transmission are essential. This study designed a low-cost electromagnetic docking guidance (EMDG) system for micro AUVs. The EMDG system is composed of a transmitter coil located on the dock and a three-axial search coil magnetometer acting as a receiver. The search coil magnetometer was optimized for small sizes while maintaining sufficient sensitivity. The signal conditioning and processing subsystem was designed to calculate the deflection angle (ß) for docking guidance. Underwater docking tests showed that the system can detect the electromagnetic signal and successfully guide AUV docking. The AUV can still perform docking in extreme positions, which cannot be realized through normal optical or acoustic guidance. This study is the first to focus on the EM guidance system for low-cost micro AUVs. The search coil sensor in the AUV is inexpensive and compact so that the system can be equipped on a wide range of AUVs.

Risk management and provider liabilities in infantile cerebral palsy based on malpractice litigation cases.

AIM: Infantile cerebral palsy (CP) severely affects the survival and quality of life of infants. CP is typically caused by multiple factors, leading to causal uncertainty of the role of medical errors in CP and resulting in frequent medical disputes. No relevant research exists on risk management and malpractice liabilities in CP, including in China. METHOD: A retrospective analysis of 400 CP malpractice litigation cases from 18th June 1999 to 23rd November 2017, collected from China Judgments Online, included basic case information, CP risk factors, medical errors, medical malpractice liability determination, and compensation. RESULTS: Up to 63.5% of infants with CP were affected by asphyxia, followed by hypoxic-ischemic encephalopathy (63.3%), neonatal infection (52.3%) and intracranial hemorrhage (36.0%). Most (89.1%) of civil judgments resulted in liability for medical errors, with the highest proportion of ultimate liability. The three most frequent medical errors were failure of completing delivery in time (30.2%), incomplete assessment of birth process detection (28.8%), and nonstandard medical records (25.3%). Each case involved 2.5 medical errors on average. No difference in the distribution of medical errors between premature and full-term CP infants (P > 0.05) was found. Compensation for damage was awarded in 91.4% of claims, and the mean value of compensation was $73,506. The mean value of the total actual loss of the family was $128,198. INTERPRETATION: Contradictions between the doctors and patients were prominent in malpractice CP litigation cases, with a total loss of $3.97 billion attributable to new CP cases in China in 2017. Asphyxia was the most frequent risk factor for CP since it may easily draw the attention of the sufferer's family. Medical service providers did not pay attention to risk management in preterm infants. The importance of fetal monitoring and standardized medical record writing should be emphasized.

Surgery scheduling optimization considering real life constraints and comprehensive operation cost of operating room.

BACKGROUND: Operating Room (OR) is the core sector in hospital expenditure, the operation management of which involves a complete three-stage surgery flow, multiple resources, prioritization of the various surgeries, and several real-life OR constraints. As such reasonable surgery scheduling is crucial to OR management. OBJECTIVE: To optimize OR management and reduce operation cost, a short-term surgery scheduling problem is proposed and defined based on the survey of the OR operation in a typical hospital in China. METHOD: The comprehensive operation cost is clearly defined considering both under-utilization and overutilization. A nested Ant Colony Optimization (nested-ACO) incorporated with several real-life OR constraints is proposed to solve such a combinatorial optimization problem. RESULTS: The 10-day manual surgery schedules from a hospital in China are compared with the optimized schedules solved by the nested-ACO. Comparison results show the advantage using the nested-ACO in several measurements: OR-related time, nurse-related time, variation in resources' working time, and the end time. CONCLUSIONS: The nested-ACO considering real-life operation constraints such as the difference between first and following case, surgeries priority, and fixed nurses in pre/post-operative stage is proposed to solve the surgery scheduling optimization problem. The results clearly show the benefit of using the nested-ACO in enhancing the OR management efficiency and minimizing the comprehensive overall operation cost.

Safety validation of decision trees for hepatocellular carcinoma.

AIM: To evaluate a different decision tree for safe liver resection and verify its efficiency. METHODS: A total of 2457 patients underwent hepatic resection between January 2004 and December 2010 at the Chinese PLA General Hospital, and 634 hepatocellular carcinoma (HCC) patients were eligible for the final analyses. Post-hepatectomy liver failure (PHLF) was identified by the association of prothrombin time < 50% and serum bilirubin > 50 µmol/L (the "50-50" criteria), which were assessed at day 5 postoperatively or later. The Swiss-Clavien decision tree, Tokyo University-Makuuchi decision tree, and Chinese consensus decision tree were adopted to divide patients into two groups based on those decision trees in sequence, and the PHLF rates were recorded. RESULTS: The overall mortality and PHLF rate were 0.16% and 3.0%. A total of 19 patients experienced PHLF. The numbers of patients to whom the Swiss-Clavien, Tokyo University-Makuuchi, and Chinese consensus decision trees were applied were 581, 573, and 622, and the PHLF rates were 2.75%, 2.62%, and 2.73%, respectively. Significantly more cases satisfied the Chinese consensus decision tree than the Swiss-Clavien decision tree and Tokyo University-Makuuchi decision tree (P < 0.01，P < 0.01); nevertheless, the latter two shared no difference (P = 0.147). The PHLF rate exhibited no significant difference with respect to the three decision trees. CONCLUSION: The Chinese consensus decision tree expands the indications for hepatic resection for HCC patients and does not increase the PHLF rate compared to the Swiss-Clavien and Tokyo University-Makuuchi decision trees. It would be a safe and effective algorithm for hepatectomy in patients with hepatocellular carcinoma.

An improved bioassay facilitates the screening of repellents against cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae).

BACKGROUND: Repellents are a common method for preventing flea bites, making an effective system for flea repellent screening advantageous. We describe an improved technique to facilitate repellent activity screening of numerous plant-based Ctenocephalides felis (cat flea) repellents. RESULTS: Two long strips of filter paper were impregnated with test compounds (dissolved in ethanol) and ethanol only, respectively. After drying, the two filter papers were glued together along the long side and inserted into a glass tube containing non-fed cat fleas. The distribution of cat fleas in each half of the filter paper was recorded after 30 min to calculate repellency. Results showed that the essential oil of Cinnamomum osmophloeum (from leaf), Taiwania cryptomerioides (from heartwood) and Plectranthus amboinicus (from leaf) exhibits repellent activity against cat fleas in a dose dependent manner. Moreover, the repellent activities against cat fleas of 2% trans-cinnamaldehyde (the main constituent of Ci. osmophloeum essential oil) and 0.5% thymol (the main constituent of P. amboinicus essential oil) are 97.6% and 90.6%, and can persist for up to 4 and 8 h, respectively. These results are comparable to those of 15% DEET. CONCLUSION: The proposed screening technique can facilitate the pre-screening of numerous flea repellents for further evaluation on animal or human subjects.

Polyphenols and triterpenes from Chaenomeles fruits: chemical analysis and antioxidant activities assessment.

Mugua, fruit of the genus Chaenomeles, is a valuable source of health food and Chinese medicine. To elucidate the bioactive compounds of five wild Chaenomeles species, extracts from fresh fruits were investigated by HPLC-DAD/ESI-MS/MS. Among the 24 polyphenol compounds obtained, 20 were flavan-3-ols (including catechin, epicatechin and procyanidin oligomers). The mean polymerisation degree (mDP) of procyanidins was examined by two acid-catalysed cleavage reactions; the mDP value was the highest in Chaenomeles sinensis and the lowest in Chaenomeles japonica. Total polyphenol content (TPC) reached 46.92 and 46.28 mg/g gallic acid equivalents (GAE) in Chaenomeles speciosa and Chaenomeles thibetica, respectively, although their main bioactive compounds were different (being epicatechin and procyanidin B2 in the former, and catechin and procyanidin B1 in the latter). These two species also exhibited equally strong free radical scavenging activities. Our results further showed that the antioxidant ability of Chaenomeles fruits was significantly correlated to their total polyphenol contents. Two triterpenes (oleanolic acid and ursolic acid) were the highest quantity in Chaenomeles cathayensis and C. thibetica, respectively.