AI-dente: an open machine learning based tool to interpret nano-indentation data of soft tissues and materials.

Nano-indentation is a promising method to identify the constitutive parameters of soft materials, including soft tissues. Especially when materials are very small and heterogeneous, nano-indentation allows mechanical interrogation where traditional methods may fail. However, because nano-indentation does not yield a homogeneous deformation field, interpreting the resulting load-displacement curves is non-trivial and most investigators resort to simplified approaches based on the Hertzian solution. Unfortunately, for small samples and large indentation depths, these solutions are inaccurate. We set out to use machine learning to provide an alternative strategy. We first used the finite element method to create a large synthetic data set. We then used these data to train neural networks to inversely identify material parameters from load-displacement curves. To this end, we took two different approaches. First, we learned the indentation forward problem, which we then applied within an iterative framework to identify material parameters. Second, we learned the inverse problem of directly identifying material parameters. We show that both approaches are effective at identifying the parameters of the neo-Hookean and Gent models. Specifically, when applied to synthetic data, our approaches are accurate even for small sample sizes and at deep indentation. Additionally, our approaches are fast, especially compared to the inverse finite element approach. Finally, our approaches worked on unseen experimental data from thin mouse brain samples. Here, our approaches proved robust to experimental noise across over 1000 samples. By providing open access to our data and code, we hope to support others that conduct nano-indentation on soft materials.

Dental pulp stem cell-derived exosomes suppress M1 macrophage polarization through the ROS-MAPK-NFκB P65 signaling pathway after spinal cord injury.

Stem cell-derived exosomes have recently been regarded as potential drugs for treating spinal cord injury (SCI) by reducing reactive oxygen species (ROS) and suppressing M1 macrophage polarization. However, the roles of ROS and exosomes in the process of M1 macrophage polarization are not known. Herein, we demonstrated that ROS can induce M1 macrophage polarization and have a concentration-dependent effect. ROS can induce M1 macrophage polarization through the MAPK-NFκB P65 signaling pathway. Dental pulp stem cell (DPSC)-derived exosomes can reduce macrophage M1 polarization through the ROS-MAPK-NFκB P65 signaling pathway in treating SCI. This study suggested that DPSC-derived exosomes might be a potential drug for treating SCI. Disruption of the cycle between ROS and M1 macrophage polarization might also be a potential effective treatment by reducing secondary damage.

Sustainable bioenergy production from marginal lands in the US Midwest.

Legislation on biofuels production in the USA and Europe is directing food crops towards the production of grain-based ethanol, which can have detrimental consequences for soil carbon sequestration, nitrous oxide emissions, nitrate pollution, biodiversity and human health. An alternative is to grow lignocellulosic (cellulosic) crops on 'marginal' lands. Cellulosic feedstocks can have positive environmental outcomes and could make up a substantial proportion of future energy portfolios. However, the availability of marginal lands for cellulosic feedstock production, and the resulting greenhouse gas (GHG) emissions, remains uncertain. Here we evaluate the potential for marginal lands in ten Midwestern US states to produce sizeable amounts of biomass and concurrently mitigate GHG emissions. In a comparative assessment of six alternative cropping systems over 20 years, we found that successional herbaceous vegetation, once well established, has a direct GHG emissions mitigation capacity that rivals that of purpose-grown crops (-851 ± 46 grams of CO(2) equivalent emissions per square metre per year (gCO(2)e m(-2) yr(-1))). If fertilized, these communities have the capacity to produce about 63 ± 5 gigajoules of ethanol energy per hectare per year. By contrast, an adjacent, no-till corn-soybean-wheat rotation produces on average 41 ± 1 gigajoules of biofuel energy per hectare per year and has a net direct mitigation capacity of -397 ± 32 gCO(2)e m(-2) yr(-1); a continuous corn rotation would probably produce about 62 ± 7 gigajoules of biofuel energy per hectare per year, with 13% less mitigation. We also perform quantitative modelling of successional vegetation on marginal lands in the region at a resolution of 0.4 hectares, constrained by the requirement that each modelled location be within 80 kilometres of a potential biorefinery. Our results suggest that such vegetation could produce about 21 gigalitres of ethanol per year from around 11 million hectares, or approximately 25 per cent of the 2022 target for cellulosic biofuel mandated by the US Energy Independence and Security Act of 2007, with no initial carbon debt nor the indirect land-use costs associated with food-based biofuels. Other regional-scale aspects of biofuel sustainability, such as water quality and biodiversity, await future study.

Optimal chin-brow vertical angle for sagittal visual fields in ankylosing spondylitis kyphosis.

PURPOSE: Chin-brow vertical angle (CBVA) is very important in correction of thoracolumbar kyphotic deformity in ankylosing spondylitis (AS), especially for the patients with cervical ankylosis. In previous study, Suk et al. stated that the patients with CBVA between -10° and 10° had better horizontal gaze. Unfortunately, in our clinical practice, we found the patients with CBVA between -10° and 10° after surgery usually complained of difficulty in cooking, cleaning, desk working and the like, although they had excellent horizontal gaze. In other words, for the patients with cervical ankylosis, good horizontal gaze existed together with poor downward gaze. Then, which condition do the patients prefer? Is there a compromise solution that makes a better quality life possible for the patients? In this research, we studied AS patients with cervical ankylosis, aiming to investigate the optimal CBVA for deformity correction. METHODS: 25 AS thoracolumbar kyphotic patients with cervical ankylosis were studied, whose function and expectation of visual field related to life quality were assessed by questionnaire before and after surgery. Pre- and post-operative CBVA were obtained on lateral photos of the patients with free-standing posture, and 50 cases of CBVA were included, which were divided into six groups according to the angle irrespective of surgery (Group A, CBVA <0°; Group B, 0° ≤ CBVA < 10°; Group C, 10° ≤ CBVA < 20°; Group D, 20° ≤ CBVA < 30°; Group E, 30° ≤ CBVA < 40°; Group F, CBVA ≥ 40°). Kruskal-Wallis test was used to assess all the groups in terms of various items in the questionnaire, while Mann-Whitney test was used to assess every two groups. RESULTS: In overall evaluation, Group C (10°-20°) obtained the optimal expectation (p < 0.05); Group B, C and D (0°-30°) obtained better function (p < 0.05), and there was no significant difference between the 3 groups. In appearance, Group A, B and C (<20°) were better than the other groups both in function and expectation (p < 0.05), without dramatic difference among the three groups. In outdoor activities, Group A, B, C and D (<30°) were better in most of the items (p < 0.05). In indoor activities, Group C and D (10-30°) were much better (p < 0.05). CONCLUSION: AS thoracolumbar kyphotic patients with cervical ankylosis had the best satisfaction when 10° ≤ CBVA < 20°.

Titanium surface polyethylene glycol hydrogel and gentamicin-loaded cross-linked starch microspheres release system for anti-infective drugs.

OBJECTIVE: To design and construct a hydrogel drug-controlled release system loaded with gentamicin on a titanium surface, and to evaluate the in vitro drug release behaviour and antibacterial properties and biocompatibility of the controlled release system. METHODS: Titanium (Ti) surface was coated with poly dopamine (PDA) substrate, and then polyethylene glycol (PEG) was attached to PDA. The composite drug microsphere controlled release layer formed by gentamicin (GEN) and cross-linked starch (CSt) were subsequently covered with poly lactic⁃co⁃glycolic acid (PLGA) as a barrier to construct a Ti-GEN-Cst-PLGA anti-infective drug controlled release system. RESULTS: The hydrogel drug release system was successfully constructed. The results of in vitro anti-staphylococcus aureus (SAU) assay, anti-staphylococcus epidermidis (SEP) assay and anti-Escherichia coli (ECO) assay showed that Ti-GEN-Cst-PLGA could effectively inhibit the growth of three bacteria. Assay in the New Zealand rabbit found that Ti-GEN-Cst-PLGA could promote wound healing at the 3rd week after implantation, and the pathology assay found that the Ti-GEN-Cst-PLGA group had less inflammatory reactions and significant tissue proliferation at the endophyte contact surface. CONCLUSION: Ti-GEN-Cst-PLGA can effectively inhibit the inflammatory response and promote wound healing, or may be a potential treatment for orthopaedic endophytes.

[Clinical efficacies of skipping two-level transpedicular wedge osteotomy for correction of severe kyphosis in ankylosing spondylitis].

OBJECTIVE: To explore the clinical efficacies of skipping two-level transpedicular wedge osteotomy in the correction of severe kyphotic deformity in ankylosing spondylitis (AS). METHODS: From January 2003 to December 2009, a total of 38 consecutive patients with AS and severe kyphosis (chin-brow vertical angle (CBVA) or global thoraco-lumbar kyphosis angle (TLKA) over 70°) undergoing skipping two-level transpedicular wedge osteotomy at the Department of Orthopedics of Chinese PLA General Hospital were reviewed retrospectively. There were 32 males and 6 females with an average age of 38.0 years (range: 22 - 65). The preoperative parameters of TLKA, T11-L2 kyphotic angle, L1-S1 lordosis angle, sagittal imbalance and CBVA were obtained from the total spine radiography or computed tomography and clinical lateral photograph. According to the characteristic curves and normal spinal alignment, their profiles of osteotomy location and angle were determined and confirmed by computer simulations. Improvement in postoperative parameters was observed and treatment satisfaction evaluated RESULTS: The average operating duration was 309 minutes and the average volume of blood loss was 2050 ml. The parameters of TLKA, T11-L2 kyphotic angle and L1-S1 lordosis angle improved from 101.0° ± 21.3°, 45.2° ± 13.6°, -28.2° ± 23.3° at preoperation to 26.0° ± 12.1°, 2.8° ± 11.6°, 28.9° ± 13.3° postoperation respectively (P < 0.01). CBVA improved from 79.4° ± 15.9° to 13.6 ° ± 10.9° (P < 0.01). The sagittal imbalance distance improved from (49 ± 13) to (15 ± 7) cm (P < 0.01). All patients could walk with orthophoria and lie horizontally postoperatively. The average follow-up was 32 months (range: 24 ∼ 78 months). Fusion of osteotomy was achieved in all patients and there was no event of loss of correction or implant failure. The SRS-22 average score improved from 1.8 to 4.2. CONCLUSION: For severe kyphosis in AS, skipping two-level transpedicular wedge osteotomy is a satisfactory and reliable approach for the correction of kyphotic deformity and it may improve appearance and function significantly.

Ultraviolet Photodetectors Based on Polymer Microwire Arrays toward Wearable Medical Devices.

Polymer micro/nanoarchitectures have attracted intense interest for wearable medical applications due to their excellent mechanical flexibility, solution processability, and tunable optoelectronic properties. Based on polymer micro/nanostructures, high-performance ultraviolet (UV) photodetectors can not only functionalize the accurate image sensing but also sustain the biocomfortable flexible devices for real-time health monitoring. The main challenges are focused on the integration of medical wearable devices, which requires large-scale assembly of polymer micro/nanostructures with controlled morphology and strict alignment. Herein, we utilized a confined assembly system through the cautious regulation for the growth of high-quality polymer 1D arrays. UV photodetectors based on these polymer microwire arrays perform a high on/off ratio of 137 and responsivity of 19.1 mA W-1. Polymer microarray photodetectors facilitate the scale-up fabrication of 14 × 18 multiplexed image sensors for highly accurate capturing the signals of Arabic numerals "1," "2," and "3." Flexible UV photodetectors based on these arrays present excellent flexibility and bending durability, maintaining 97% of their original on/off ratio after 4000 cycles with a 10 mm bending radius. UV photodetection signals were also collected from the attached flexible devices on the back skin of the mouse, demonstrating the great potential in wearable medical photodetection.

A Cross-Sectional, Multicenter Study Examining the Validation and Adaptation of the Chinese ROWAN Foot Pain Assessment Questionnaire.

BACKGROUND: The 39-item ROwan Foot Pain Assessment Questionnaire (ROFPAQ) has affective, cognitive, and sensory dimensions to evaluate chronic foot pain. However, to date, the ROFPAQ has only been validated in English and Spanish versions. A simplified Chinese version of ROFPAQ is still not available, even though China has a large population of patients with foot pain. OBJECTIVE: This study's aim was to translate the ROFPAQ into a Chinese version and assess its reliability and validity in Chinese patients with chronic foot pain. STUDY DESIGN: A cross-sectional, multicenter descriptive study. SETTING: This study took place at the Chinese PLA General Hospital, PLA Strategic Support Force Characteristic Medical Center and Wenzhou integrated traditional Chinese and Western Medicine Hospital Affiliated to Zhejiang traditional Chinese Medicine University. METHODS: The ROFPAQ-C (Chinese) was developed by a forward/backward translation protocol and cross-cultural adaptation from the United Kingdom to China, and from English to Chinese Putonghua. A total of 194 patients from 3 centers with chronic foot pain were recruited for test-retest measures from July 2020 though September 2021. RESULTS: Adequate internal consistencies (Cronbach's Alpha) in 3 domains ranged from 0.875 to 0.799 for the cognitive, from 0.795 to 0.629 for the affective, and from 0.801 to 0.811 for the sensory, as well as for the total score from 0.880 to 0.815. Adequate test-retest reliability by intraclass correlation coefficient (ICC) were shown in the cognitive 0.712 (95% CI 0.636 to 0.775), the affective 0.929 (95% CI 0.906 to 0.946), the sensory 0.753 (95% CI 0.685 to 0.808), and the total score 0.932 (95% CI 0.910 to 0.948). Adequate item-total correlations were shown for the cognitive from 0.848 to 0.825, the affective from 0.918 to 0.908, and the sensory from 0.943 to 0.855. LIMITATIONS: The original ROFPAQ with 39 items was developed from a podiatry department of the health care national service of the United Kingdom. CONCLUSIONS: The ROFPAQ-C can be used as a valid and reliable tool for chronic foot pain in the Chinese population.

DPSCs Protect Architectural Integrity and Alleviate Intervertebral Disc Degeneration by Regulating Nucleus Pulposus Immune Status.

Intervertebral disc (IVD) degeneration is the primary cause for low back pain that has a high prevalence in modern society and poses enormous economic burden on patients. Few effective therapeutic strategies are available for IVD degeneration treatment. To understand the biological effects of dental pulp stem cells (DPSCs) on nucleus pulposus (NP) cells, we carried out RNA sequencing, bioinformatic analysis which unveiled gene expression differences, and pathway variation in primarily isolated patients' NP cells after treatment with DPSCs supernatant. Western blot and immunofluorescence were used to verify these molecular alterations. Besides, to evaluate the therapeutic effect of DPSCs in IVD degeneration treatment, DPSCs were injected into a degeneration rat model in situ, with treatment outcome measured by micro-CT and histological analysis. RNA sequencing and in vitro experiments demonstrated that DPSCs supernatant could downregulate NP cells' inflammation-related NF-κB and JAK-STAT pathways, reduce IL-6 production, increase collagen II expression, and mitigate apoptosis. In vivo results showed that DPSCs treatment protected the integrity of the disc structure, alleviated extracellular matrix degradation, and increased collagen fiber expression. In this study, we verified the therapeutic effect of DPSCs in an IVD degeneration rat model and elucidated the underlying molecular mechanism of DPSCs treatment, which provides a foundation for the application of DPSCs in IVD degeneration treatment.

Temporary use of shape memory spinal rod in the treatment of scoliosis.

NiTinol shape memory alloy is characterized by its malleability at low temperatures and its ability to return to a preconfigured shape above its activation temperature. This process can be utilized to assist in scoliosis correction. The goal of this retrospective study was to evaluate the clinical and radiographic results of intraoperative use of shape memory alloy rod in the correction of scoliosis. From May 2002 to September 2006, 38 scoliosis patients (ranging from 50° to 120°; 22 cases over 70°) who underwent shape memory alloy-assisted correction in our institute were reviewed. During the operation, a shape memory alloy rod served as a temporary correction tool. Following correction, the rod was replaced by a rigid rod. The mean blood loss at surgery was 680 ± 584 ml; the mean operative time was 278 ± 62 min. The major Cobb angle improved from an average 78.4° preoperatively to 24.3° postoperatively (total percent correction 71.4%). In 16 patients with a major curve <70° and flexibility of 52.7%, the deformity improved from 58.4° preoperatively to 12.3° postoperatively (percent correction, 78.9%). In 22 patients with a major curve >70° and flexibility of 25.6%, the deformity improved from 94.1° preoperatively to 30.1° postoperatively (percent correction, 68.1%). Only one case had a deep infection. There were no neurologic, vascular or correction-related complications such as screw pullout or metal fracture. The study shows that the intraoperative use of a shape memory rod is a safe and effective method to correct scoliosis.

Clinical application of computer-designed polystyrene models in complex severe spinal deformities: a pilot study.

Surgical treatment of complex severe spinal deformity, involving a scoliosis Cobb angle of more than 90 degrees and kyphosis or vertebral and rib deformity, is challenging. Preoperative two-dimensional images resulting from plain film radiography, computed tomography (CT) and magnetic resonance imaging provide limited morphometric information. Although the three-dimensional (3D) reconstruction CT with special software can view the stereo and rotate the spinal image on the screen, it cannot show the full-scale spine and cannot directly be used on the operation table. This study was conducted to investigate the application of computer-designed polystyrene models in the treatment of complex severe spinal deformity. The study involved 16 cases of complex severe spinal deformity treated in our hospital between 1 May 2004 and 31 December 2007; the mean +/- SD preoperative scoliosis Cobb angle was 118 degrees +/- 27 degrees. The CT scanning digital imaging and communication in medicine (DICOM) data sets of the affected spinal segments were collected for 3D digital reconstruction and rapid prototyping to prepare computer-designed polystyrene models, which were applied in the treatment of these cases. The computer-designed polystyrene models allowed 3D observation and measurement of the deformities directly, which helped the surgeon to perform morphological assessment and communicate with the patient and colleagues. Furthermore, the models also guided the choice and placement of pedicle screws. Moreover, the models were used to aid in virtual surgery and guide the actual surgical procedure. The mean +/- SD postoperative scoliosis Cobb angle was 42 degrees +/- 32 degrees, and no serious complications such as spinal cord or major vascular injury occurred. The use of computer-designed polystyrene models could provide more accurate morphometric information and facilitate surgical correction of complex severe spinal deformity.

Hierarchical assembly of dual-responsive biomineralized polydopamine-calcium phosphate nanocomposites for enhancing chemo-photothermal therapy by autophagy inhibition.

The induction of autophagy in cancer cells would occur in response to several therapy strategies, including chemotherapy and photothermal therapy (PTT). Hence, combined autophagy inhibition has been regarded as a prevailing strategy to enhance treatment sensitivity in cancers. Herein, dual pH/thermal responsive biomineralized nanocomposites (PCNPs) were rationally designed and prepared based on the hierarchical assembly of calcium phosphate (CaP) and polydopamine (PDA). The first step in the self-assembly process involves the incorporation of hydrophobic chemotherapeutic docetaxel (DTX) into the CaP nanoparticles. Next, PDA was utilized as the coating to hierarchically self-assemble onto the surface of CaP through a simple self-polymerization of dopamine. Third, the autophagy inhibitor chloroquine (CQ) was absorbed onto the surface of PDA via non-covalent interactions, forming PCNPs/DC. CQ was the only FDA approved autophagy inhibitor in clinical trials that could inhibit autophagosome fusion and degradation. The resulting PCNPs/DC could exhibit dual pH/thermal responsive properties due to the acid-sensitive CaP core and the photothermal effect of the PDA coating. Effective inhibition of autophagy in cancer cells could be realized by blocking the lysosome and weakening the degradation of autolysosomes by PCNPs/DC. Interestingly, complementary autophagy inhibition could therefore sensitize the effects of chemo-photothermal therapy both in vitro and in vivo with negligible toxicity. Therefore, these hierarchically assembled biomineralized nanocomposites would be used as a prevailing strategy to sensitize chemo-photothermal therapy by complementary autophagy inhibition.

Intradural lysis and peripheral nerve implantation for traumatic obsolete incomplete paralysis.

Twenty-eight patients who suffered traumatic obsolete incomplete paralysis were treated with intradural lysis and peripheral nerve implantation by a microsurgery technique. The endorachis was opened and the fibrous bands adhering to the spinal cord from the arachnoid, pia mater spinalis, ligamenta denticulatum, and the initial part of the nerve root were completely relieved. The abnormal spinal cord was then opened by three to six incisions, which were each 0.1 mm to 0.2 mm deep and longer than the abnormal portion. A cyst found in the back or side of the spinal cord was opened and the liquid in it was drained. After that, the denuded spineurium and perineurium of the autogenous sural nerve were grafted, which makes the character and aspect of the nerve like the cauda equine. The nerve was longitudinally implanted into the incised spinal cord, and the cyst was waded with grafted nerve and at least one of them is ectropion sutured with the pia mater with 9-0 scatheless wire as a drain. Finally, the endorachis was covered by sacrospinal muscle flap. These patients were followed for 2 years to 8 years (average 3.5 years), and the sensibility and motion of each increased at least one grade. The strength of the main muscle was increased two grades and reached four grades in 11 patients, and the capability to walk was recovered. Relieving of the adhesion in the endorhachis, carving the cicatricial spinal cord, and implanting the autogenous peripheral nerve yields good results by initial clinical observation for traumatic obsolete and incomplete paralysis.

Thermal behavior and kinetic study for catalytic co-pyrolysis of biomass with plastics.

The present study aims to investigate the thermal decomposition behaviors and kinetics of biomass (cellulose/Douglas fir sawdust) and plastics (LDPE) in a non-catalytic and catalytic co-pyrolysis over ZSM-5 catalyst by using a thermogravimetric analyzer (TGA). It was found that there was a positive synergistic interaction between biomass and plastics according to the difference of weight loss (ΔW), which could decrease the formation of solid residue at the end of the experiment. The first order reaction model well fitted for both non-catalytic and catalytic co-pyrolysis of biomass with plastics. The activation energy (E) of Cellulose-LDPE-Catalyst and DF-LDPE-Catalyst are only 89.51 and 54.51kJ/mol, respectively. The kinetics analysis showed that adding catalyst doesn't change the decomposition mechanism. As a result, the kinetic study on catalytic co-pyrolysis of biomass with plastics was suggested that the catalytic co-pyrolysis is a promising technique that can significantly reduce the energy input.

Optimizing carbon efficiency of jet fuel range alkanes from cellulose co-fed with polyethylene via catalytically combined processes.

Enhanced carbon yields of renewable alkanes for jet fuels were obtained through the catalytic microwave-induced co-pyrolysis and hydrogenation process. The well-promoted ZSM-5 catalyst had high selectivity toward C8-C16 aromatic hydrocarbons. The raw organics with improved carbon yield (∼44%) were more principally lumped in the jet fuel range at the catalytic temperature of 375°C with the LDPE to cellulose (representing waste plastics to lignocellulose) mass ratio of 0.75. It was also observed that the four species of raw organics from the catalytic microwave co-pyrolysis were almost completely converted into saturated hydrocarbons; the hydrogenation process was conducted in the n-heptane medium by using home-made Raney Ni catalyst under a low-severity condition. The overall carbon yield (with regards to co-reactants of cellulose and LDPE) of hydrogenated organics that mostly match jet fuels was sustainably enhanced to above 39%. Meanwhile, ∼90% selectivity toward jet fuel range alkanes was attained.

Mechanical properties and cytocompatibility of carbon fibre reinforced nano-hydroxyapatite/polyamide66 ternary biocomposite.

BACKGROUND AND METHODS: Fibre-reinforced composites with good strength and ductility as bone repair biomaterials have been attracting increasing attention in biomedical applications. In the present study, a novel ternary composite was prepared using carbon fibre (CF) to reinforce a nano-hydroxyapatite/polyamide66 composite (HA/PA). The interface and mechanical strength of the ternary composite (CF/HA/PA) were characterised. In addition, to assess the cytocompatibility, the composite was co-cultured with MG-63 cells, and the cell morphology, MTT, and ALP were tested. RESULTS: The results indicated that CFs were uniformly distributed in the HA/PA matrix with random orientation and that the CFs bonded well to the HA/PA matrix. The reinforced ternary composite exhibited a compressive strength of 116-212 MPa, a bending strength of 89-138 MPa, a tensile strength of 109-181 MPa, with the breaking elongation ratio of 6.2-9.1%, and a tensile modulus of 2.9-5.8 GPa, with the values varying with increasing CF content from 5 to 20 (mass fraction). The MG-63 cells of normal phenotype were well extended and spread onto the ternary composite surface. In addition, its proliferation and differentiation on the composite surface were significantly increased with time, indicating that the incorporation of CFs into HA/PA had little negative effects on MG-63 cells. CONCLUSIONS: The incorporation of CFs into a HA/PA66 composite improved the strength and ductility and introduced no negative effects on the cytocompatibility. Hence, the CF/HA/PA ternary composite has potential to be used as a bone repair materials and in fixation devices.

Bio-based phenols and fuel production from catalytic microwave pyrolysis of lignin by activated carbons.

The aim of this study is to explore catalytic microwave pyrolysis of lignin for renewable phenols and fuels using activated carbon (AC) as a catalyst. A central composite experimental design (CCD) was used to optimize the reaction condition. The effects of reaction temperature and weight hourly space velocity (WHSV, h(-1)) on product yields were investigated. GC/MS analysis showed that the main chemical compounds of bio-oils were phenols, guaiacols, hydrocarbons and esters, most of which were ranged from 71% to 87% of the bio-oils depending on different reaction conditions. Bio-oils with high concentrations of phenol (45% in the bio-oil) were obtained. The calorific value analysis revealed that the high heating values (HHV) of the lignin-derived biochars were from 20.4 to 24.5 MJ/kg in comparison with raw lignin (19 MJ/kg). The reaction mechanism of this process was analyzed.

Transfected early growth response gene-1 DNA enzyme prevents stenosis and occlusion of autogenous vein graft in vivo.

The aim of this study was to detect the inhibitory action of the early growth response gene-1 DNA enzyme (EDRz) as a carrying agent by liposomes on vascular smooth muscle cell proliferation and intimal hyperplasia. An autogenous vein graft model was established. EDRz was transfected to the graft vein. The vein graft samples were obtained on each time point after surgery. The expression of the EDRz transfected in the vein graft was detected using a fluorescent microscope. Early growth response gene-1 (Egr-1) mRNA was measured using reverse transcription-PCR and in situ hybridization. And the protein expression of Egr-1 was detected by using western blot and immunohistochemistry analyses. EDRz was located at the media of the vein graft from 2 to 24 h, 7 h after grafting. The Egr-1 protein was mainly located in the medial VSMCs, monocytes, and endothelium cells during the early phase of the vein graft. The degree of VSMC proliferation and thickness of intima were obviously relieved compared with the no-gene therapy group. EDRz can reduce Egr-1 expression in autogenous vein grafts, effectively restrain VSMC proliferation and intimal hyperplasia, and prevent vascular stenosis and occlusion after vein graft.

[Cage implantation for the treatment of osteonecrosis of the femoral head].

OBJECTIVE: To explore the midterm efficacy of superelastic cage implantation for the treatment of osteonecrosis of femoral head (ONFH). METHODS: From July 1996 to January 1998, 54 patients (75 hips) of ONFH were treated with superelastic cage and followed up. Among 54 patients, 5 patients were lost to follow up and 3 patients were dead of myocardial infarction, renal failure and gastric cancer, respectively. Forty-six patients completed follow up including 32 males and 14 females, aged from 21 to 61 with an average of 39 years old. Twenty-nine hips were classified as Ficat Stage II and 36 as Stage II. Harris score was 58.20 +/- 13.82. All patients were evaluated both clinically and radiographically. RESULTS: Postoperatively, forty-six patients (65 hips) were followed up for 86 to 125 months with an average of 8 years and 8 months. Harris score was 80.78 +/- 18.77. Twenty-nine hips were rated excellent, 21 good, 2 fair and 13 poor. A total of 76.9% of overall clinical results were rated as good or excellent. Eight hips (12.3%) with the cage broken were turned to total hip replacement. Radiographic evaluation: 16 hips (24.6%) rated as grade I , 34 (52.3%) grade II and 15 (23.1%) grade III. CONCLUSION: Superelastic cage implantation is one of alternative treatments for ONFH at early and midterm stages. However, long-term follow-up is needed to know whether it is able to cure ONFH and whether cages will be broken as time passes by.