The regenerating islet-derived members (Reg), a group of small secretory proteins, which are involved in cell proliferation or differentiation in digestive organs, are upregulated in several gastrointestinal cancers...The regenerating islet-derived members (Reg), a group of small secretory proteins, which are involved in cell proliferation or differentiation in digestive organs, are upregulated in several gastrointestinal cancers, functioning as trophic or antiapoptotic factors. Regenerat- ing islet-derived type Ⅳ (RegⅣ), a member of the Reg gene family, has been reported to be overexpressed in gastroenterological cancers. RegIV overexpression in tumor cells has been associated with carcinogen- esis, cell growth, survival and resistance to apoptosis. Cancer tissue expressing RegIV is generally associated with more malignant characteristics than that with- out such expression, and RegⅣ is considered a novel prognostic factor as well as diagnostic marker in some gastroenterological cancers. We previously investigated the expression levels of RegⅣ mRNA of 202 surgical colorectal cancer specimens with quantitative real-time reverse-transcriptase polymerase chain reaction and reported that a higher level of RegⅣ gene expression was a significant independent predictor of colorec- tal cancer. The biologic functions of RegⅣ protein in cancer tissue, associated with carcinogenesis, anti- apoptosis and invasiveness, are being elucidated by molecular investigations using transfection techniques or neutralizing antibodies of RegIV, and the feasibility of antibody therapy targeting RegIV is being assessed. These studies may lead to novel therapeutic strate- gies for gastroenterological cancers expressing RegⅣ. This review article summarizes the current information related to biological functions as well as clinical impor- tance of RegⅣ gene to clarify the significance of Reg~ expression in gastroenterological cancers.展开更多
AIM: To study the action of hepatitis virus infectionassociated genes at transcription level during liver regeneration (LR). METHODS: Hepatitis virus infection-associated genes were obtained by collecting the data...AIM: To study the action of hepatitis virus infectionassociated genes at transcription level during liver regeneration (LR). METHODS: Hepatitis virus infection-associated genes were obtained by collecting the data from databases and retrieving the correlated articles, and their expression changes in the regenerating rat liver were detected with the rat genome 230 2.0 array. RESULTS: Eighty-eight genes were found to be associated with liver regeneration. The number of genes initially and totally expressed during initial LR [0.5-4 h affer partial hepatectomy (PH)], transition from (30 to G1 (4-6 h affer PH), cell proliferation (6-66 h after PH), cell differentiation and reorganization of structurefunction (66-168 h after PH) was 37, 8, 48, 3 and 37, 26, 80, 57, respectively, indicating that the genes were mainly triggered at the early stage of LR (0.5-4 h after PH), and worked at different phases. These genes were classified into 5 types according to their expression similarity, namely 37 up-regulated, 9 predominantly upregulated, 34 down-regulated, 6 predominantly downregulated and 2 up/down-regulated genes. Their total up- and down-regulation frequencies were 359 and 149 during LR, indicating that the expression of most genes was enhanced, while the expression of a small number of genes was attenuated during LR. According to time relevance, they were classified into 12 groups (0.5 and 1h, 2 and 4h, 6h, 8 and 12h, 16 and 96h, 18 and 24 h, 30 and 42 h, 36 and 48 h, 54 and 60 h, 66 and 72 h, 120 and 144 h, 168 h), demonstrating that the cellular physiological and biochemical activities during LR were fluctuated. According to expression changes of the genes, their expression patterns were classified into 23 types, suggesting that the cellular physiological and biochemical activities during LR were diverse and complicated. CONCLUSION: The anti-virus infection capacity of regenerating liver can be enhanced and 88 genes play an important role in LR.展开更多
The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The fir...The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The first consists of creating a supporting scaffold,either synthetically or by decellularization of human or animal organs,and seeding cells on the scaffold,where they will mature either in bioreactors or in vivo.This strategy seems to offer the quickest route to clinical translation,as demonstrated by the development of liver organoids from rodent livers which were repopulated with organ specific cells of animal and/or human origin.Liver bioengineering has potential for transplantation and for toxicity testing during preclinical drug development.The second possibility is to induce liver regeneration of dead or resected tissue by manipulating cell pathways.In fact,it is well known that the liver has peculiar regenerative potential which allows hepatocyte hyperplasia after amputation of liver volume.Infusion of autologous bone marrow cells,which aids in liver regeneration,into patients was shown to be safe and to improve their clinical condition,but the specific cells responsible for liver regeneration have not yet been determined and the underlying mechanisms remain largely unknown.A complete understanding of the cell pathways and dynamics and of the functioning of liver stem cell niche is necessary for the clinical translation of regenerative medicine strategies.As well,it will be crucial to elucidate the mechanisms through which cells interact with the extracellular matrix,and how this latter supports and drives cell fate.展开更多
A series of pot experiments and field trials were carried out to evaluate the effects of arbuscular mycor- rhizal fungi (AMF) on activities of soil enzymes and carbon sequestration capacity in reclaimed mine soil. A...A series of pot experiments and field trials were carried out to evaluate the effects of arbuscular mycor- rhizal fungi (AMF) on activities of soil enzymes and carbon sequestration capacity in reclaimed mine soil. A complex substrate of coal gangue, fly ash and sludge was used as reclaimed mine soil, and ryegrass was planted with AMF inoculation to construct a plant-complex substrate-microbe ecological restoration sys- tem. The changes to the soil organic carbon (SOC), activities of soil enzymes and glomalin-related soil protein (GRSP) were measured and the effects of AMF on activities of soil enzymes and carbon sequestra- tion capacity (n reclaimed mine soil were analyzed. The results show that the contents of GRSP (total glo- malin (TG) and easily extractable glomalin (EEG)), SOC and activities of enzymes increased, and the increments were higher in the AMF inoculation treated plant-complex substrate-microbe ecological res- toration systems than those with no AMF inoculated treatments after 12 months of ryegrass growth. TG, EEG and soil enzyme activity have a significant positive correlation, and the correlative coefficient was 0.427-0.573; SOC and TG, EEG have a significant positive correlation (p 〈 0.01 ), indicating that AMF plays an important role in carbon sequestration of reclaimed mine soils.展开更多
AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T...AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T- hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P 〈 0.01).CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application.展开更多
A number of congenital and acquired disorders require esophageal tissue replacement.Various surgical techniques,such as gastric and colonic interposition,are standards of treatment,but frequently complicated by stenos...A number of congenital and acquired disorders require esophageal tissue replacement.Various surgical techniques,such as gastric and colonic interposition,are standards of treatment,but frequently complicated by stenosis and other problems.Regenerative medicine approaches facilitate the use of biological constructs to replace or regenerate normal tissue function.We review the literature of esophageal tissue engineering,discuss its implications,compare the methodologies that have been employed and suggest possible directions for the future.Medline,Embase,the Cochrane Library,National Research Register and ClinicalTrials.gov databases were searched with the following search terms:stem cell and esophagus,esophageal replacement,esophageal tissue engineering,esophageal substitution.Reference lists of papers identified were also examined and experts in this field contacted for further information.All full-text articles in English of all potentially relevant abstracts were reviewed.Tissue engineering has involved acellular scaffolds that were either transplanted with the aim of being repopulated by host cells or seeded prior to transplantation.When acellular scaffolds were used to replace patch and short tubular defects they allowed epithelial and partial muscular migration whereas when employed for long tubular defects the results were poor leading to an increased rate of stenosis and mortality.Stenting has been shown as an effective means to reduce stenotic changes and promote cell migration,whilst omental wrapping to induce vascularization of the construct has an uncertain benefit.Decellularized matrices have been recently suggested as the optimal choice for scaffolds,but smart polymers that will incorporate signalling to promote cell-scaffold interaction may provide a more reproducible and available solution.Results in animal models that have used seeded scaffolds strongly suggest that seeding of both muscle and epithelial cells on scaffolds prior to implantation is a prerequisite for complete esophageal replacement.Novel approaches need to be designed to allow for peristalsis and vascularization in the engineered esophagus.Although esophageal tissue engineering potentially offers a real alternative to conventional treatments for severe esophageal disease,important barriers remain that need to be addressed.展开更多
Medical models, or "phantoms," have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification a...Medical models, or "phantoms," have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification and validation, and medical devices development. Such new applications demand high-fidelity, patient-specific, tissue-mimicking medical phantoms that can not only closely emulate the geometric structures of human organs, but also possess the properties and functions of the organ structure. With the rapid advancement of three-dimensional (3D) printing and 3D bioprinting technologies, many researchers have explored the use of these additive manufacturing techniques to fabricate functional medical phantoms for various applications. This paper reviews the applications of these 3D printing and 3D bioprinting technologies for the fabrication of functional medical phantoms and bio-structures. This review specifically discusses the state of the art along with new developments and trends in 3D printed functional medical phantoms (i.e., tissue-mimicking medical phantoms, radiologically relevant medical phantoms, and physiological medical phantoms) and 3D bio-printed structures (i.e., hybrid scaffolding materials, convertible scaffolds, and integrated sensors) for regenerated tissues and organs.展开更多
Cardiovascular disease is a leading cause of death throughout the world. The demand for new thera- peutic interventions is increasing. Although pharmacological and surgical interventions dramatically improve the quali...Cardiovascular disease is a leading cause of death throughout the world. The demand for new thera- peutic interventions is increasing. Although pharmacological and surgical interventions dramatically improve the quality of life of cardiovascular disease patients, cheaper and less invasive approaches are always preferable. Biomaterials, both natural and synthetic, exhibit great potential in cardiac repair and regeneration, either as a carrier for drug delivery or as an extracellular matrix substitute scaffold. In this review, we discuss the current treatment options for several cardiovascular diseases, as well as types of biomaterials that have been investigated as potential therapeutic interventions for said diseases. We especially highlight investigations into the possible use of conductive polymers for correcting ischemic heart disease-induced conduction abnormalities, and the generation of biological pacemakers to im- orove the conduction oathwav in heart block.展开更多
The use of the residues from renewable feedstock, besides the production of fuels, but also for the generation of other chemicals products, has become a priority. Superior plants have considerable potential as carbohy...The use of the residues from renewable feedstock, besides the production of fuels, but also for the generation of other chemicals products, has become a priority. Superior plants have considerable potential as carbohydrate, aryl and fatty acids sources. However, the separation of the main constituents of the samples is necessary for several purposes in the biorefinery concept. The acid hydrolysis and pyrolysis processes are very promising technology, however, some adjustments in the conditions of pyrolysis are needed for different biomasses since carbohydrates were detected (14%-17%) in the residues after the conventional acid hydrolysis of these uncommon biomasses (coffee husk and banana stem and stalk). On the other hand, it was showed that, by pyrolysis, it is possible to obtain from the solid residue after acid hydrolysis: pyrogenic carbon (charcoal with a yield of 48.5%-52.7%) for agriculture use (biochar) and valuable chemicals in the pyrolysis oil biooil fraction (that accounted by 26.4%-29.0%, free of water), such as lignin monomers (32.6%-56.4% of the bio-oil) and fatty acids (30%-52.5%).展开更多
An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onoblychis viciaefolia was established. In SH medium supplemented with 1 mg/L 2, 4-dichlorophenoxy-acetic acid...An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onoblychis viciaefolia was established. In SH medium supplemented with 1 mg/L 2, 4-dichlorophenoxy-acetic acid (2,4-D), 0.5 mg/L kinetin (KT) and 0.2 mg/L naphthalene acetic acid (NAA), the division frequency of protoplastderived cells reached uP to over 60 %, and microcalli were obtained in 5-6 wk. Upon transferring them on agar solidified MS medium plus 2 mg/L indole-3-acetic acid (IAA), shoots were induced. After cultivating them on MS medium with or without IAA, roots were regenerated.Chromosome number of all protoplast-regenerated plants examined were normal (2n=28). The protoplast-derived calli and plants grew vigorously on the medium containing 10 mmol/L HYP.展开更多
In an attempt to propagate and conserve the rare, showy bulbous plants of Iris bismarckiana, newly recorded to the flora of Jordan and to contribute to the conservation the wild lris species in Jordan, a simple rapid,...In an attempt to propagate and conserve the rare, showy bulbous plants of Iris bismarckiana, newly recorded to the flora of Jordan and to contribute to the conservation the wild lris species in Jordan, a simple rapid, time consuming protocol has been developed using plant regeneration via somatic embryogenesis. Somatic embryogenesis was induced in zygotic embryo culture on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (8 mg/L) as the sole plant growth regulator, where both embryogenesis calli and somatic embryos were induced. Separation of embryos from embryo clusters was necessary to enhance the frequency of germination. Germination was stimulated by separation of embryos successfully from embryo clusters and transferred onto fresh MS medium. Data obtained were analyzed as a complete random design with three replications. Calli fragments that were transferred to embryogenesis induction medium (EIM) produced white embryo-like globular structures within two weeks. Within three more weeks, clusters of structures at various stages of development could be found on the same callus. The applied technique is rewarding and encouraging for further research on the endangered wild species of Iris in Jordan.展开更多
Knee osteoarthritis (OA) is the most common form of arthritis worldwide. The incidence of this disease is rising and its treatment poses an economic burden. Two early targets of knee OA treatment include the predomi...Knee osteoarthritis (OA) is the most common form of arthritis worldwide. The incidence of this disease is rising and its treatment poses an economic burden. Two early targets of knee OA treatment include the predominant symptom of pain, and cartilage damage in the knee joint. Current treatments have been beneficial in treating the disease but none is as effective as total knee arthroplasty (TKA). However, while TKA is an end-stage solution of the disease, it is an invasive and expensive procedure, Therefore, innovative regenerative engineering strategies should be established as these could defer or annul the need for a TKA. Several biomaterial and cell-based therapies are currently in development and have shown early promise in both preclinical and clinical studies. The use of advanced biomaterials and stem cells independently or in conjunction to treat knee OA could potentially reduce pain and regenerate fo- cal articular cartilage damage. In this review, we discuss the pathogenesis of pain and cartilage damage in knee OA and explore novel treatment options currently being studied, along with some of their limitations.展开更多
Biofuels could contribute, on a worldwide basis, to the attainment of international energy-policy objectives in three ways: by reducing dependence on imported oil; by increasing the availability of renewable energy s...Biofuels could contribute, on a worldwide basis, to the attainment of international energy-policy objectives in three ways: by reducing dependence on imported oil; by increasing the availability of renewable energy sources; and by addressing environmental issues. It is an absolute necessity in South Africa to utilise sustainable and renewable energy sources, such as biofuels, but the production of bio-ethanol will ultimately place pressure on the limited and fragile agricultural resources of the country. Because of the proposed bio-ethanol plant at Bothaville this paper will firstly develop a methodology suitable for South African conditions in order to establish whether agricultural crops could be used for the production of biofuels. Secondly, it probes the suitability of maize as a biofuel crop in this country by investigating four possible bio-ethanol potential scenarios which are qualitatively formulated to provide a comprehensive overview of this study. Only in the best-case scenario could maize produce the required volumes as set out by the South African government for 2013.展开更多
To use the renewable fuels for marine field is still very limited due to the need of newly developed technology, highly requested safety (for gas fuel) and high price of biodiesel. Therefore, with some advantages, s...To use the renewable fuels for marine field is still very limited due to the need of newly developed technology, highly requested safety (for gas fuel) and high price of biodiesel. Therefore, with some advantages, such as: simple producing process, reasonable price and simple modification technology needed, the blended SVO (straight vegetable oil) is recommended as suitable fuel for the marine application. Even though, there are some disadvantages of the blended SVO, such as a weak stability, layer separation in low temperature and some others. In order to apply the blended SVO as alternative fuel for marine diesel engines without the mentioned disadvantages, the paper will introduce a method to design and produce a fuel continuous mixer to make a blended SVO (palm oil).展开更多
Background: Safflower regeneration through tissue culture has long been limited to low frequency and lack of an efficient protocol that suitable for most safflower cultivars. In past decades, researches had been carri...Background: Safflower regeneration through tissue culture has long been limited to low frequency and lack of an efficient protocol that suitable for most safflower cultivars. In past decades, researches had been carried out to investigate safflower regeneration through tissue culture and great progress had been made. Objective: To investigate factors that affect safflower regeneration through tissue culture principally. Methods: This article summarized available literatures about advancements in safflower regeneration, especially discussed factors affecting safflower tissue culture in detail. Results: Safflower regeneration was fairly hard than other congeneric plants, such as chrysanthemum. The genotype, seedling age, type of explants, medium components, plant growth regulators and other additives all had specific influences on safflower tissue culture. More deepgoing researches need to be undertaken to establish an effective safflower regeneration system.展开更多
Biodiesel (fatty acid methyl ester) has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing bi...Biodiesel (fatty acid methyl ester) has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing biodiesel from conventional sources such as soybean, canola, sunflower, and coconut oils. Current efforts are directed towards the development of new non-edible resources. Among these Jatropha Curcas comes at the forefront. In Egypt, Jatropha Curcas has grown successfully using primary treated wastewater. Also, extensive R&D efforts identified the optimum conditions for the various processing stages namely crushing, extraction, transesterification and purification. Based on the research findings, the techno-economic appraisal of biodiesel production from Jatropha Curcas is conducted. Two nominal capacities namely 8,000 and 50,000 metric tons/yr have been proposed. Several scenarios have been formulated to take into consideration varying productivity (3.4 to 5.8 ton fruits per 4,000 m^2 (acre)) and varying recovery rates of oil from seeds. Economic indicators including capital and production costs for the various processing stages and revenues according to current prices of oil and cake have been obtained. The price of biodiesel that provides a simple rate of return (SRR) on investments of 10% was in the range of $0.3-0.7/liter for the different assumed scenarios which is lower than the prevailing price of biodiesel (about $1/liter) in the US. Thus, in view of experimental results and economic assumptions, there are positive prospects for the production of biodiesel from Jatropha Curcas under Egyptian conditions.展开更多
US EPA recently issued the final definition for a renewable fuel establishes rule for the revised Renewable Fuel Standard RFS the compliance for each part of its name: (i) to II (Renewable Fuel Standard). The mai...US EPA recently issued the final definition for a renewable fuel establishes rule for the revised Renewable Fuel Standard RFS the compliance for each part of its name: (i) to II (Renewable Fuel Standard). The main be a fuel and (ii) to be produced from renewable biomass. This paper addresses the challenges faced by biomass derived fuels on meeting the specifications of those fuels (gasoline, diesel and heating oil). Biomass-derived products contain oxygenates, some of which might enhance certain fuel specifications, but some others may have deteriorating effects. On directly derived from biomass pyrolysis have been demonstrated to the basis of available data published in the literature, the fuels be far from the concept of "substantially similar" transportation fuels. Upgrading is required to convert pyrolysis products into fuels that meet specifications. The economical viability of upgrading still faces confirmation, and imposes several technical challenges for truly attractive cost-effective approaches.展开更多
Natural landscapes provide ability to live of local people. Because of the lack of information about the rent streams which are created in non-wood resources usage sphere, the priority of the state policy is given to ...Natural landscapes provide ability to live of local people. Because of the lack of information about the rent streams which are created in non-wood resources usage sphere, the priority of the state policy is given to the wood crude product. The purpose of this article is to explain why the ecology-economic accounting of wildlife resources is needed. Methodological approaches of the environment resources by the United Nations allow to define the rent streams created in sector of private households. Based on full economic value of non-wood resources the measurement of rent flows will allow to carry out updating of a state policy and to develop the mechanism of natural landscapes preservation and to increase socially-ecological efficiency of it's using.展开更多
The variation of phosphorus (P) bioavailability in terms of water soluble P (WSP ), readily desorbable P (RDP), algal available P (AAP), and NaHCo3 extracting P (Olsen-P) in the re-suspended sediments was in...The variation of phosphorus (P) bioavailability in terms of water soluble P (WSP ), readily desorbable P (RDP), algal available P (AAP), and NaHCo3 extracting P (Olsen-P) in the re-suspended sediments was investigated in laboratory experiments, in which the waters and sediments were taken from campus canal. The results indicate that sediment re-suspension can promote the migration, of soluble reactive P (SRP) from overlying water to sediments. The contents of AAP and Olsen-P in re-suspended sediments reduced obviously, whereas the values of the sediments in the control increased slightly, compared with the initial state, indicating that the P bioavailability in the sediments could be rcduced evidently due to sediment re-suspension. The content and characteristics of iron-bound P (BD-P) significantly affect the formation of AAP. The formation of OlservP has close relationship with the contents of BD-P, almninium-botmd P (AI-P), and organic P (NaOH-nrP).展开更多
文摘The regenerating islet-derived members (Reg), a group of small secretory proteins, which are involved in cell proliferation or differentiation in digestive organs, are upregulated in several gastrointestinal cancers, functioning as trophic or antiapoptotic factors. Regenerat- ing islet-derived type Ⅳ (RegⅣ), a member of the Reg gene family, has been reported to be overexpressed in gastroenterological cancers. RegIV overexpression in tumor cells has been associated with carcinogen- esis, cell growth, survival and resistance to apoptosis. Cancer tissue expressing RegIV is generally associated with more malignant characteristics than that with- out such expression, and RegⅣ is considered a novel prognostic factor as well as diagnostic marker in some gastroenterological cancers. We previously investigated the expression levels of RegⅣ mRNA of 202 surgical colorectal cancer specimens with quantitative real-time reverse-transcriptase polymerase chain reaction and reported that a higher level of RegⅣ gene expression was a significant independent predictor of colorec- tal cancer. The biologic functions of RegⅣ protein in cancer tissue, associated with carcinogenesis, anti- apoptosis and invasiveness, are being elucidated by molecular investigations using transfection techniques or neutralizing antibodies of RegIV, and the feasibility of antibody therapy targeting RegIV is being assessed. These studies may lead to novel therapeutic strate- gies for gastroenterological cancers expressing RegⅣ. This review article summarizes the current information related to biological functions as well as clinical impor- tance of RegⅣ gene to clarify the significance of Reg~ expression in gastroenterological cancers.
基金Supported by the National Natural Science Foundation of China, No. 30270673
文摘AIM: To study the action of hepatitis virus infectionassociated genes at transcription level during liver regeneration (LR). METHODS: Hepatitis virus infection-associated genes were obtained by collecting the data from databases and retrieving the correlated articles, and their expression changes in the regenerating rat liver were detected with the rat genome 230 2.0 array. RESULTS: Eighty-eight genes were found to be associated with liver regeneration. The number of genes initially and totally expressed during initial LR [0.5-4 h affer partial hepatectomy (PH)], transition from (30 to G1 (4-6 h affer PH), cell proliferation (6-66 h after PH), cell differentiation and reorganization of structurefunction (66-168 h after PH) was 37, 8, 48, 3 and 37, 26, 80, 57, respectively, indicating that the genes were mainly triggered at the early stage of LR (0.5-4 h after PH), and worked at different phases. These genes were classified into 5 types according to their expression similarity, namely 37 up-regulated, 9 predominantly upregulated, 34 down-regulated, 6 predominantly downregulated and 2 up/down-regulated genes. Their total up- and down-regulation frequencies were 359 and 149 during LR, indicating that the expression of most genes was enhanced, while the expression of a small number of genes was attenuated during LR. According to time relevance, they were classified into 12 groups (0.5 and 1h, 2 and 4h, 6h, 8 and 12h, 16 and 96h, 18 and 24 h, 30 and 42 h, 36 and 48 h, 54 and 60 h, 66 and 72 h, 120 and 144 h, 168 h), demonstrating that the cellular physiological and biochemical activities during LR were fluctuated. According to expression changes of the genes, their expression patterns were classified into 23 types, suggesting that the cellular physiological and biochemical activities during LR were diverse and complicated. CONCLUSION: The anti-virus infection capacity of regenerating liver can be enhanced and 88 genes play an important role in LR.
文摘The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The first consists of creating a supporting scaffold,either synthetically or by decellularization of human or animal organs,and seeding cells on the scaffold,where they will mature either in bioreactors or in vivo.This strategy seems to offer the quickest route to clinical translation,as demonstrated by the development of liver organoids from rodent livers which were repopulated with organ specific cells of animal and/or human origin.Liver bioengineering has potential for transplantation and for toxicity testing during preclinical drug development.The second possibility is to induce liver regeneration of dead or resected tissue by manipulating cell pathways.In fact,it is well known that the liver has peculiar regenerative potential which allows hepatocyte hyperplasia after amputation of liver volume.Infusion of autologous bone marrow cells,which aids in liver regeneration,into patients was shown to be safe and to improve their clinical condition,but the specific cells responsible for liver regeneration have not yet been determined and the underlying mechanisms remain largely unknown.A complete understanding of the cell pathways and dynamics and of the functioning of liver stem cell niche is necessary for the clinical translation of regenerative medicine strategies.As well,it will be crucial to elucidate the mechanisms through which cells interact with the extracellular matrix,and how this latter supports and drives cell fate.
基金supported by the Environmental Science andTechnology Fund of Environmental Protection Department of Jiangsu Province,China (No. 2007024)
文摘A series of pot experiments and field trials were carried out to evaluate the effects of arbuscular mycor- rhizal fungi (AMF) on activities of soil enzymes and carbon sequestration capacity in reclaimed mine soil. A complex substrate of coal gangue, fly ash and sludge was used as reclaimed mine soil, and ryegrass was planted with AMF inoculation to construct a plant-complex substrate-microbe ecological restoration sys- tem. The changes to the soil organic carbon (SOC), activities of soil enzymes and glomalin-related soil protein (GRSP) were measured and the effects of AMF on activities of soil enzymes and carbon sequestra- tion capacity (n reclaimed mine soil were analyzed. The results show that the contents of GRSP (total glo- malin (TG) and easily extractable glomalin (EEG)), SOC and activities of enzymes increased, and the increments were higher in the AMF inoculation treated plant-complex substrate-microbe ecological res- toration systems than those with no AMF inoculated treatments after 12 months of ryegrass growth. TG, EEG and soil enzyme activity have a significant positive correlation, and the correlative coefficient was 0.427-0.573; SOC and TG, EEG have a significant positive correlation (p 〈 0.01 ), indicating that AMF plays an important role in carbon sequestration of reclaimed mine soils.
基金Supported by National "863" Program of China , No. 2002AA214011
文摘AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T- hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P 〈 0.01).CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application.
文摘A number of congenital and acquired disorders require esophageal tissue replacement.Various surgical techniques,such as gastric and colonic interposition,are standards of treatment,but frequently complicated by stenosis and other problems.Regenerative medicine approaches facilitate the use of biological constructs to replace or regenerate normal tissue function.We review the literature of esophageal tissue engineering,discuss its implications,compare the methodologies that have been employed and suggest possible directions for the future.Medline,Embase,the Cochrane Library,National Research Register and ClinicalTrials.gov databases were searched with the following search terms:stem cell and esophagus,esophageal replacement,esophageal tissue engineering,esophageal substitution.Reference lists of papers identified were also examined and experts in this field contacted for further information.All full-text articles in English of all potentially relevant abstracts were reviewed.Tissue engineering has involved acellular scaffolds that were either transplanted with the aim of being repopulated by host cells or seeded prior to transplantation.When acellular scaffolds were used to replace patch and short tubular defects they allowed epithelial and partial muscular migration whereas when employed for long tubular defects the results were poor leading to an increased rate of stenosis and mortality.Stenting has been shown as an effective means to reduce stenotic changes and promote cell migration,whilst omental wrapping to induce vascularization of the construct has an uncertain benefit.Decellularized matrices have been recently suggested as the optimal choice for scaffolds,but smart polymers that will incorporate signalling to promote cell-scaffold interaction may provide a more reproducible and available solution.Results in animal models that have used seeded scaffolds strongly suggest that seeding of both muscle and epithelial cells on scaffolds prior to implantation is a prerequisite for complete esophageal replacement.Novel approaches need to be designed to allow for peristalsis and vascularization in the engineered esophagus.Although esophageal tissue engineering potentially offers a real alternative to conventional treatments for severe esophageal disease,important barriers remain that need to be addressed.
文摘Medical models, or "phantoms," have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification and validation, and medical devices development. Such new applications demand high-fidelity, patient-specific, tissue-mimicking medical phantoms that can not only closely emulate the geometric structures of human organs, but also possess the properties and functions of the organ structure. With the rapid advancement of three-dimensional (3D) printing and 3D bioprinting technologies, many researchers have explored the use of these additive manufacturing techniques to fabricate functional medical phantoms for various applications. This paper reviews the applications of these 3D printing and 3D bioprinting technologies for the fabrication of functional medical phantoms and bio-structures. This review specifically discusses the state of the art along with new developments and trends in 3D printed functional medical phantoms (i.e., tissue-mimicking medical phantoms, radiologically relevant medical phantoms, and physiological medical phantoms) and 3D bio-printed structures (i.e., hybrid scaffolding materials, convertible scaffolds, and integrated sensors) for regenerated tissues and organs.
文摘Cardiovascular disease is a leading cause of death throughout the world. The demand for new thera- peutic interventions is increasing. Although pharmacological and surgical interventions dramatically improve the quality of life of cardiovascular disease patients, cheaper and less invasive approaches are always preferable. Biomaterials, both natural and synthetic, exhibit great potential in cardiac repair and regeneration, either as a carrier for drug delivery or as an extracellular matrix substitute scaffold. In this review, we discuss the current treatment options for several cardiovascular diseases, as well as types of biomaterials that have been investigated as potential therapeutic interventions for said diseases. We especially highlight investigations into the possible use of conductive polymers for correcting ischemic heart disease-induced conduction abnormalities, and the generation of biological pacemakers to im- orove the conduction oathwav in heart block.
文摘The use of the residues from renewable feedstock, besides the production of fuels, but also for the generation of other chemicals products, has become a priority. Superior plants have considerable potential as carbohydrate, aryl and fatty acids sources. However, the separation of the main constituents of the samples is necessary for several purposes in the biorefinery concept. The acid hydrolysis and pyrolysis processes are very promising technology, however, some adjustments in the conditions of pyrolysis are needed for different biomasses since carbohydrates were detected (14%-17%) in the residues after the conventional acid hydrolysis of these uncommon biomasses (coffee husk and banana stem and stalk). On the other hand, it was showed that, by pyrolysis, it is possible to obtain from the solid residue after acid hydrolysis: pyrogenic carbon (charcoal with a yield of 48.5%-52.7%) for agriculture use (biochar) and valuable chemicals in the pyrolysis oil biooil fraction (that accounted by 26.4%-29.0%, free of water), such as lignin monomers (32.6%-56.4% of the bio-oil) and fatty acids (30%-52.5%).
文摘An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onoblychis viciaefolia was established. In SH medium supplemented with 1 mg/L 2, 4-dichlorophenoxy-acetic acid (2,4-D), 0.5 mg/L kinetin (KT) and 0.2 mg/L naphthalene acetic acid (NAA), the division frequency of protoplastderived cells reached uP to over 60 %, and microcalli were obtained in 5-6 wk. Upon transferring them on agar solidified MS medium plus 2 mg/L indole-3-acetic acid (IAA), shoots were induced. After cultivating them on MS medium with or without IAA, roots were regenerated.Chromosome number of all protoplast-regenerated plants examined were normal (2n=28). The protoplast-derived calli and plants grew vigorously on the medium containing 10 mmol/L HYP.
文摘In an attempt to propagate and conserve the rare, showy bulbous plants of Iris bismarckiana, newly recorded to the flora of Jordan and to contribute to the conservation the wild lris species in Jordan, a simple rapid, time consuming protocol has been developed using plant regeneration via somatic embryogenesis. Somatic embryogenesis was induced in zygotic embryo culture on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (8 mg/L) as the sole plant growth regulator, where both embryogenesis calli and somatic embryos were induced. Separation of embryos from embryo clusters was necessary to enhance the frequency of germination. Germination was stimulated by separation of embryos successfully from embryo clusters and transferred onto fresh MS medium. Data obtained were analyzed as a complete random design with three replications. Calli fragments that were transferred to embryogenesis induction medium (EIM) produced white embryo-like globular structures within two weeks. Within three more weeks, clusters of structures at various stages of development could be found on the same callus. The applied technique is rewarding and encouraging for further research on the endangered wild species of Iris in Jordan.
文摘Knee osteoarthritis (OA) is the most common form of arthritis worldwide. The incidence of this disease is rising and its treatment poses an economic burden. Two early targets of knee OA treatment include the predominant symptom of pain, and cartilage damage in the knee joint. Current treatments have been beneficial in treating the disease but none is as effective as total knee arthroplasty (TKA). However, while TKA is an end-stage solution of the disease, it is an invasive and expensive procedure, Therefore, innovative regenerative engineering strategies should be established as these could defer or annul the need for a TKA. Several biomaterial and cell-based therapies are currently in development and have shown early promise in both preclinical and clinical studies. The use of advanced biomaterials and stem cells independently or in conjunction to treat knee OA could potentially reduce pain and regenerate fo- cal articular cartilage damage. In this review, we discuss the pathogenesis of pain and cartilage damage in knee OA and explore novel treatment options currently being studied, along with some of their limitations.
文摘Biofuels could contribute, on a worldwide basis, to the attainment of international energy-policy objectives in three ways: by reducing dependence on imported oil; by increasing the availability of renewable energy sources; and by addressing environmental issues. It is an absolute necessity in South Africa to utilise sustainable and renewable energy sources, such as biofuels, but the production of bio-ethanol will ultimately place pressure on the limited and fragile agricultural resources of the country. Because of the proposed bio-ethanol plant at Bothaville this paper will firstly develop a methodology suitable for South African conditions in order to establish whether agricultural crops could be used for the production of biofuels. Secondly, it probes the suitability of maize as a biofuel crop in this country by investigating four possible bio-ethanol potential scenarios which are qualitatively formulated to provide a comprehensive overview of this study. Only in the best-case scenario could maize produce the required volumes as set out by the South African government for 2013.
文摘To use the renewable fuels for marine field is still very limited due to the need of newly developed technology, highly requested safety (for gas fuel) and high price of biodiesel. Therefore, with some advantages, such as: simple producing process, reasonable price and simple modification technology needed, the blended SVO (straight vegetable oil) is recommended as suitable fuel for the marine application. Even though, there are some disadvantages of the blended SVO, such as a weak stability, layer separation in low temperature and some others. In order to apply the blended SVO as alternative fuel for marine diesel engines without the mentioned disadvantages, the paper will introduce a method to design and produce a fuel continuous mixer to make a blended SVO (palm oil).
基金Supported by the National Natural Science Foundation of China Granted Project(81173484)
文摘Background: Safflower regeneration through tissue culture has long been limited to low frequency and lack of an efficient protocol that suitable for most safflower cultivars. In past decades, researches had been carried out to investigate safflower regeneration through tissue culture and great progress had been made. Objective: To investigate factors that affect safflower regeneration through tissue culture principally. Methods: This article summarized available literatures about advancements in safflower regeneration, especially discussed factors affecting safflower tissue culture in detail. Results: Safflower regeneration was fairly hard than other congeneric plants, such as chrysanthemum. The genotype, seedling age, type of explants, medium components, plant growth regulators and other additives all had specific influences on safflower tissue culture. More deepgoing researches need to be undertaken to establish an effective safflower regeneration system.
文摘Biodiesel (fatty acid methyl ester) has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing biodiesel from conventional sources such as soybean, canola, sunflower, and coconut oils. Current efforts are directed towards the development of new non-edible resources. Among these Jatropha Curcas comes at the forefront. In Egypt, Jatropha Curcas has grown successfully using primary treated wastewater. Also, extensive R&D efforts identified the optimum conditions for the various processing stages namely crushing, extraction, transesterification and purification. Based on the research findings, the techno-economic appraisal of biodiesel production from Jatropha Curcas is conducted. Two nominal capacities namely 8,000 and 50,000 metric tons/yr have been proposed. Several scenarios have been formulated to take into consideration varying productivity (3.4 to 5.8 ton fruits per 4,000 m^2 (acre)) and varying recovery rates of oil from seeds. Economic indicators including capital and production costs for the various processing stages and revenues according to current prices of oil and cake have been obtained. The price of biodiesel that provides a simple rate of return (SRR) on investments of 10% was in the range of $0.3-0.7/liter for the different assumed scenarios which is lower than the prevailing price of biodiesel (about $1/liter) in the US. Thus, in view of experimental results and economic assumptions, there are positive prospects for the production of biodiesel from Jatropha Curcas under Egyptian conditions.
文摘US EPA recently issued the final definition for a renewable fuel establishes rule for the revised Renewable Fuel Standard RFS the compliance for each part of its name: (i) to II (Renewable Fuel Standard). The main be a fuel and (ii) to be produced from renewable biomass. This paper addresses the challenges faced by biomass derived fuels on meeting the specifications of those fuels (gasoline, diesel and heating oil). Biomass-derived products contain oxygenates, some of which might enhance certain fuel specifications, but some others may have deteriorating effects. On directly derived from biomass pyrolysis have been demonstrated to the basis of available data published in the literature, the fuels be far from the concept of "substantially similar" transportation fuels. Upgrading is required to convert pyrolysis products into fuels that meet specifications. The economical viability of upgrading still faces confirmation, and imposes several technical challenges for truly attractive cost-effective approaches.
文摘Natural landscapes provide ability to live of local people. Because of the lack of information about the rent streams which are created in non-wood resources usage sphere, the priority of the state policy is given to the wood crude product. The purpose of this article is to explain why the ecology-economic accounting of wildlife resources is needed. Methodological approaches of the environment resources by the United Nations allow to define the rent streams created in sector of private households. Based on full economic value of non-wood resources the measurement of rent flows will allow to carry out updating of a state policy and to develop the mechanism of natural landscapes preservation and to increase socially-ecological efficiency of it's using.
基金National High Technology Research and Development Program(863) of China(No.2003AA601070)National Natural Science Foundation of China(No.50908154)
文摘The variation of phosphorus (P) bioavailability in terms of water soluble P (WSP ), readily desorbable P (RDP), algal available P (AAP), and NaHCo3 extracting P (Olsen-P) in the re-suspended sediments was investigated in laboratory experiments, in which the waters and sediments were taken from campus canal. The results indicate that sediment re-suspension can promote the migration, of soluble reactive P (SRP) from overlying water to sediments. The contents of AAP and Olsen-P in re-suspended sediments reduced obviously, whereas the values of the sediments in the control increased slightly, compared with the initial state, indicating that the P bioavailability in the sediments could be rcduced evidently due to sediment re-suspension. The content and characteristics of iron-bound P (BD-P) significantly affect the formation of AAP. The formation of OlservP has close relationship with the contents of BD-P, almninium-botmd P (AI-P), and organic P (NaOH-nrP).