铝合金模压操作中各因素对锻件产生折叠的影响

折叠缺陷是铝合金模锻件生产中发生的最主要的缺陷。长期以来困扰着模锻件的生产。针对这种缺陷进行分析和研究,找出了模压操作中产生折叠的各因素,并提出了解决的方法,使模锻件成品率大幅度提高。

Fanconi Anemia and Ubiquitination

Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity to DNA cross-linking agents, such as mitomycin C （MMC）. To date, at least 12 FA genes have been found deleted or mutated in FA cells, and 10 FA gene products form a core complex involved in FA/BRCA2 DNA repair pathway-FA pathway. The ubiquitin E3 ligase FANCL, an important factor of FA core complex, co-functions with a new ubiquitin conjugating enzyme UBE2T to catalyze the monoubiquitination of FANCD2. FANCD2-Ub binds BRCA2 to form a new complex located in chromatin foci and then take part in DNA repair process. The deubiquitylating enzyme USP1 removes the mono-ubiquitin from FANCD2-Ub following completion of the repair process, then restores the blocked cell cycle to normal order by shutting off the FA pathway. In a word, the FANCD2 activity adjusted exquisitely by ubiquitination and/or deubiquitination in vivo may co-regulate the FA pathway involving in variant DNA repair pathway.

Roles of NF-κB in central nervous system damage and repair

NF-κB family is a kind of nuclear factors in B lymphocyte that can bind to the immunoglobulin κ-chain enhancer and enhance transcriptional activity. NF-κB/Rel proteins, as a dimeric transcription factor, control the expression of genes that regulate a broad range of biological processes through canonical and non-canonical pathways. In the central nervous system, NF-κB controls inflammatory reactions and the apoptotic cell death following nerve injury. It also contributes to the infarction and cell death in stroke models and patients. However, NF-κB is essential for neurosurvival as well. NF-κB activation is a part of recovery process that may protect neurons against oxidative-stresses or brain ischemia-induced apoptosis and neurodegeneration. Inhibition of NF-κB may reduce its neuroprotection activity. Hence the dual opposite effects of NF-κB on cells. The ultimate survival or death of neurons depends on which, where and when the NF-κB factors are activated.

DNA Damage and Repair of Two Ecotypes of Phragmites communis Subjected to Water Stress

In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence analysis of DNA unwinding (FADU). The results showed that the residual double strand DNA percentages (dsDNA%) in dune reed (DR) were significantly higher than those in swamp reed (SR) treated with either 20% or 30% PEG 6000. This meant that the DNA of DR was less damaged in comparison with SR. Similarly, DR resisted DNA damage more strongly than SR as reactive oxygen species (ROS) increased by adding ROS producers diethyldithio carbamate (DDC), H2O2 and Fe2+ of different concentrations. Meanwhile, treating PEG stressed SR with ROS scavengers such as dimethyl sulphoxide (DMSO) and ascorbic acid (Vc) resulted in the reduction of DNA damage, suggesting that ROS could cause DNA damage. In addition, the DNA repair for water-stressed reeds indicated that DR repaired DNA damage much faster and more completely. This might be the first indication that drought stress led to DNA damage in plants and that drought resistance of plants was closely related to DNA damage and repair.

Bacterial expression and purification of biologically active human TFF2

Human trefoil factor 2 （hTFF2） is considered as one of the most important initiators of mucosal healing in the gastrointestinal tract by promoting cell migration and suppressing apoptosis. However, it is hard to obtain hTFF2 from human tissue and many recombinant hTFF2 produced in vitro exist as fusion proteins. The purpose of the present study was to produce native hTFF2 while maintaining its biological activities. The open reading frame of hTFF2 was inserted into a pET-32a（＋） expression vector, and hTFF2-TRX fusion protein was successfully expressed in Escherichia coli and purified by Nickel-nitrilotriacetic acid affinity chromatography and reverse-phase HPLC steps. The recombinant fusion protein （purity〉95%） was cleaved by Factor Xa at 23 ~C to release hTFF2. After removal of Factor Xa and undigested fusion proteins, hTFF2 was purified and identified by SDS-PAGE and Western blotting. The yield of recombinant hTFF2 was about 5 mg/L. The recombinant hTFF2 could promote IEC-6 cells migration and in vitro wound healing via the activation of ERK1/2. Recombinant hTFF2 could also inhibit apoptosis of HCT-116 cells induced by 50 lamol/L ceramide In summary, our results showed that the recombinant hTFF2 was expressed in E. coli and successfully purified after cleavage with the fusion partner with high yield while maintaining its biological activities. Recombinant hTFF2 might be useful for investigating the molecular mechanism of hTFF2 and development of hTFF2-related drugs.

Relationship between acute kidney injury before thoracic endovascular aneurysm repair and in-hospital outcomes in patients with type B acute aortic dissection

Objective Acute kidney injury （AKI） frequently occurs after catheter-based interventional procedures and increases mortality. However, the implications of AKI before thoracic endovascular aneurysm repair （TEVAR） of type B acute aortic dissection （AAD） remain unclear. This study evaluated the incidence, predictors, and in-hospital outcomes of AKI before TEVAR in patients with type B AAD. Methods Between 2009 and 2013, 76 patients were retrospectively evaluated who received TEVAR for type B AAD within 36 h from symptom onset. The patients were classified into no-AKI vs. AKI groups, and the severity of AKI was further staged according to kidney disease： im- proving global outcomes criteria before TEVAR. Results The incidence of preoperative AKI was 36.8%. In-hospital complications was significantly higher in patients with preoperative AKI compared with no-AKI （50.0% vs. 4.2%, respectively; P 〈 0.001）, including acute renal failure （21.4% vs. O, respectively; P 〈 0.001）, and they increased with severity of AKI （P 〈 0.001）. The maximum levels of body tem- perature and white blood cell count were significantly related to maximum serum creatinine level before TEVAR. Multivariate analysis showed that systolic blood pressure on admission （OR： 1.023; 95% CI： 1.003-1.044; P ： 0.0238） and bilateral renal artery involvement （OR： 19.076; 95% CI： 1.914 190.164; P = 0.0120） were strong predictors of preoperative AKI. Conclusions Preoperative AKI frequently occurred in patients with type B AAD, and correlated with higher in-hospital complications and enhanced inflammatory reaction. Systolic blood pressure on admission and bilateral renal artery involvement were major risk factors for AKI before TEVAR.

Cell and gene therapy for arrhythmias： Repair of cardiac conduction damage

Action potentials generated in the sinoatrial node （SAN） dominate the rhythm and rate of a healthy human heart. Subsequently, these action potentials propagate to the whole heart via its conduction system. Abnormalities of impulse generation and/or propagation in a heart can cause arrhythmias. For example, SAN dysfunction or conduction block of the atrioventricular node can lead to serious bradycardia which is currently treated with an implanted electronic pacemaker. On the other hand, conduction damage may cause reentrant tachyarrhythmias which are primarily treated pharmacologically or by medical device-based therapies, including defibrillation and tissue ablation. However, drug therapies sometimes may not be effective or are associated with serious side effects. Device-based therapies for cardiac arrhythmias, even with well developed technology, still face inadequacies, limitations, hardware complications, and other challenges. Therefore, scientists are actively seeking other alternatives for antiarrhythmic therapy. In particular, cells and genes used for repairing cardiac conduction damage/defect have been investigated in various studies both in vitro and in vivo. Despite the complexities of the excitation and conduction systems of the heart, cell and gene-based strategies provide novel alternatives for treatment or cure of cardiac arrhythmias. This review summarizes some highlights of recent research progress in this field.

Electromagnetic Stimulation Combined with Aloe vera Increases Collagen Reorganization in Burn Repair

Objectives： Burns are shown as a clinical problem for their severity and multiple complications due to the time required to heal. Therapies that improve their healing are of great importance, especially for being minimally invasive, of low cost and best performance, all related to the speed and quality of healing. This study investigated the effects of the magnetic electro stimulator Haihuá CD9 isolated or in association with Aloe vera in rats skin burns. Methods： Experimental groups （n = 30/group） were： （C） Carbopol gel; （F） A. vera/Carbopol gel; （H） Haihuá＋Carbopol gel; （H＋F） Haihuá＋A. vera/Carbopol gel. Samples were collected on the 7th, 14th, and 21st experimental days for structural and morphometric analysis, hydroxyproline and glycosaminoglycans quantification, zymography for MMP-2 and MMP-9 and Western Blotting for TGF-β1, VEGF, Collagen I and III. Key findings： The expression of TGF-β1 in H＋F was increased on the 7th day and of MMP-9 on the 7th and 14th days. The expression of VEGF increased in the first experimental periods and decreased in the last for the treated groups. There was an increase in the fibroblasts and birefringent collagen fibers in groups treated with Haihuá isolated or in association with A. vera in all periods. The quantification of collagen I increased, while collagen III decreased in H＋F. The higher amount of GAGs and MMP-2 active isoform was detected in H and H＋F during all periods. Conclusions： Considering the results of the present study, electromagnetic stimulation in association with the A. vera extract promoted an increase in the number of fibroblasts, GAGs content, MMP-2 activity, the deposition and organization of collagen fibers, favoring the repair of injuries to second degree burns, and may also present therapeutic potential in this injury type.

Protective effects of Rad23 protein on ultraviolet damage to HeLa cells

Protein Rad23, a nucleotide excision repair factor, mainly involves in repairing the DNA damage from environment, such as UV light. The function of Rad23 protein involved in DNA damage repair from many environmental factors has been studied extensively, but it is not clear from ultraviolet irradiation. To further investigate the photo-protective function of Rad23 protein on HeLa cells damaged from UV light irradiation, firstly, HeLa cells were irradiated by UV light and incubated with the fusion protein of pCold-Rad23, then the cell viability and apoptosis rate were detected by MTT and Hoechst33342/Pl fluorescent staining, respectively. The results show that the recombinant Rad23 protein can protect the HeLa cells from UV irradiation, and inhibit the apoptosis of HeLa cell by UV irradiation.

Peripheral nerve repair by conduits made of human hair keratin: An experimental study

Objective: To explore the method to repair injured peripheral nerve using conduits made of human hair keratin (HHK). Methods: The tibial nerves of rabbits were transected leaving a gap 10 mm in length between the 2 severed ends, which were either routinely sutured or bridged using HHK nerve conduits. Electro-physiological , anatomical and histological examinations were performed at different time postoperatively. Results: Electrophysiological study showed more obvious improvement in the neural function recovery in rabbits with HHK conduits bridging as compared with that in rabbits with routine suture. In the former group, HHK conduits were gradually degraded and absorbed with large amount of myelinated nerve fibers and Schwann cells regenerated around HHK conduits. In the latter group, however, the nerve tissues around the suture were degenerated and replaced by connective tissues. Conclusion: HHK may induce the regeneration of the nerve fibers and provides an ideal approach to repair nerve damages.

Investigation of the active components and mechanism of Sanao Decoction in treating chronic cough by network pharmacology and molecular docking

Objective To investigate the active components and mechanism of Sanao Decoction(三拗汤,SAD)in treating chronic cough based on network pharmacology and molecular docking.Methods Active components and their targets were obtained from the Traditional Chinese Medicine Systems and Pharmacology Database and Analysis Platform(TCMSP),Bioinformatics Analysis Tool for Molecular mech ANism of Traditional Chinese Medicine(BATMAN-TCM)database,and the literature.The component-target regulatory network and protein-protein interaction(PPI)network were constructed by Cytoscape 3.7.2,and a bioinformatics analysis was performed to identify the significant pathways and their relevant targets.Molecular docking of the core active components and relevant targets was performed.Results A total of 98 active components of SAD and the corresponding 113 drug targets were identified.The component-target regulatory network and PPI network were successfully established.Results of the bioinformatics analysis indicated that 2281 Gene Ontology(GO)terms were enriched in chronic cough,including 2062 terms were in biological processes,77 in cellular components,and 142 in molecular functions,and top 20 significant pathways in Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis.Molecular docking study demonstrated that quercetin,luteolin,kaempferol,and naringenin were in good agreement with the corresponding targets.Conclusion The active compounds of SAD,such as quercetin,luteolin,kaempferol,and naringenin,may act on AKT1,MAPK1,RELA,EGFR,and Bcl-2 and regulate the PI3 K-Akt signaling pathway,AGE-RAGE signaling pathway,and fluid shear stress and atherosclerosis pathway to exert the effects of anti-inflammatory,anti-airway remodeling,anti-oxidant stress effects,and repair airway damage,thus treating chronic cough.

The DNA injury-repair of esophageal cancer EC109 cells to diallyl trisulfide (DATS) combining radiation

Objective: The aim of our study was to investigate the effect of diallyl trisulfide (DATS) combining radiation on DNA injury-repair of Esophageal cancer EC109 cells. Methods: Using 10 and 20 μg/mL DATS on EC109 cells, and taking X-ray radiation 24 h later. Investigate the radiosensitization effect of DATS on EC109 cells by clone formation, and the mechanism of DNA injury-repair by Comet Assay. Results: The clone formation resulted that DATS had radiosensitization effect on EC109 cells. Radiosensitization enhancement ratios of 10 and 20 μg/mL DATS in combination with radiation were 1.55, 1.64 (Do) and 1.43, 1.75 (Dq) respectively. In the comet assay, the TM (tail moments) of 20 μg/mL DATS combining radiation group lines at 0 h, 2 h, 6 h and 24 h were 7.16 ± 2.61, 3.65 ± 2.06, 2.09 ± 0.83, 1.45 ± 1.37 respectively. They were slightly increased than radiation group (0.95 ± 0.65, 0.11 ± 0.07, 0.1 ± 0.05, 0.11 ± 0.08) and DATS group (1.81 ± 1.23, 1.58 ± 1.40, 0.45 ± 0.25, 0.60 ± 0.40) (P < 0.01). The result showed that DATS combining radiation had the effect of increasing DNA damage and inhibiting DNA repair on EC109 cells. Conclusion: DATS has radiosensitization effect on Esophageal cancer EC109 cells. And the effect is probably related with DNA injury-repair.

Casearia sylvestris Improved Cutaneous Burn Repair in Diabetic Rats

Objectives： The burn repair associated with diabetes complications showed considerable changes in the healing process and the development of alternative therapies to favor the repair is important. This study investigated the efficacy of the Casearia sylvestris in the burn repair in diabetic and non-diabetic rats. Methods： The animals were divided into four groups （n = 20）： （C） non-diabetics treated with carbopol gel; （G） non-diabetic treated with C. sylvestris extract in carbopol gel; （DM-C） diabetics treated with carbopol gel; （DM-G） diabetics treated with C. sylvestris extract in carbopol gel. Burn was induced using a metal plate （2 cm diameter/120 °C/20 sec）. Samples were collected on the 3rd, 7th, 14th and 21st days after the injury for histomorphometric analysis （inflammatory infiltrate, fibroblasts, blood vessels and collagen）, MPO （Myeloperoxidase） and NAG （N-Acetilglicosaminidase） dosage, hydroxyproline, glycosaminoglycans, TGF-β1, VEGF, collagen I and III. Key findings： C. sylvestris decreased the inflammatory process during the experimental period in diabetic and non-diabetic animals which has been demonstrated by MPO, NAG quantification, and TGF-β1 expression. C. sylvestris also increased blood vessels and decreased VEGF expression during the studied period in non-diabetic animals. Fibroplasia and collagenase were increased in all experimental periods in the DM-G group by means of de hydroxyproline quantification, collagen I, collagen III and glycosaminoglycans. Conclusions： C. sylvestris application can modulate favorably the time of inflammation and collagenous process in the repair of burn injuries in diabetic rats.

Damage Assessment, Repair and Field Test of Steel Lattice Shell after Fire

A real case of a steel lattice shell suffering a fire was studied. Based on the theory of field modeling, fire dynamic simulator (FDS) was used to identify the temperature field. The damage mechanism of the structure was determined by FEM analysis. After damage assessment, the shell was repaired with the pipe-encasement method. Finally, field test was employed to check the capacity of the structure after repair. The numerical study results indicate that the damage assessment agrees well with field inspection, verifying the accuracy of fire numerical simulation and FEM analysis. The field test results prove that the pipe-encasement method is secure and reasonable, and the repaired shell is safe.

Transferring superior gluteal nerve to pudendal nerve in reconstructing functional impairment in simple conus medullaris or pudendal nerve injury

Objective: 1Department of Anatomy, College of Basic Medical Sciences, Second Military Medical University, Shanghai 200433, China 2Department of Orthopedic Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China Abstract Objective: To study the anatomical basis of transferring the superior gluteal nerve to the pudendal nerve in reconstructing the functional impairment in simple conus medullaris or pudendal nerve injury. Methods: Superior gluteal nerve and pudendal nerve were observed and measured by the gross and microsurgical anatomical methods in 62 sides of 31 adult cadavers. Results: Superior gluteal nerve came out of the superior foreman of piriformis as 1 to 4 branches(29.03%,56.45%,12.90% and 1.61% respectively) and the pelvic-leaving points were mainly in the middle 1/3(85.48%) of the line from the posterior superior iliac spine to the ischial tuberosity. The length of the inferior branch of the superior gluteal nerve was more than 5 cm, and the distance between the pelvic-leaving points of the superior gluteal nerve and pudandal nerve was about 4 cm only. The pudendal nerve left the pelvis mainly in the middle 1/3(48.39%) of the line from the posterior superior iliac spine to the ischial tuberosity,or at the junction of its inferior-middle 1/3(46.77%). In clinic, we have successfully made the operation transferring the superior gluteal nerve to the pudendal nerve in 3 patients suffered from the injury of conus medullaris. Conclusion: Distance between the pelvic-leaving points of the superior gluteal nerve and the pudendal nerve is close, so the inferior branch of the gluteal nerve can be anastomosed with the pudendal nerve directly. Transferring the superior gluteal nerve with higher spinal segemental origin to the pudendal nerve of a lower spinal segemental origin is practical and easy.

Implications of oxidative damage to proteins and DNA in aging and its intervention by caloric restriction and exercise

In this short review we describe implications of age-related changes of protein and DNA oxidation as a public mechanism of biological aging. Oxidatively modified protein and DNA have been demonstrated to increase with advancing age in rodents. Half-life of proteins is extended and DNA repair activity declines in old animals. Dietary restriction initiated late in life can shorten the half-life of proteins to levels of young animals, thus contributing to reduce level of altered proteins in old animals by the regimen. Regular exercise reduced oxidatively modified proteins in the brain with improved cognitive functions. It attenuated oxidative stress in the liver, i.e., ameliorating activation of nuclear factor κB, increasing reduced glutathione, and decreasing oxidized guanine base in nuclear and mitochondrial DNA. These findings suggest that regular exercise has systemic effects in reducing oxidative stress. Thus, life-styles such as diet and exercise may extend health span, by up-regulating overall anti-oxidant capacities that include proteins involved in protein turnover and DNA repair, resulting in reduction of damaged proteins and DNA that potentially promote physiological and pathological aging.

Modeling of DSBs Generation and Repair Process under Ion Radiation

Under acute perturbations from outside, cell can trigger the self-defense mechanisms in fighting against these genome stresses. To simulate the investigation of the complicated mechanisms of cellular responding DNA damage at single cell level, a model of the double strand breaks (DSBs) generation and repair process is proposed under continuous effect of acute IR. Under different IR dose domains, this model can be used to simulate the complicated interactions among vital components within the cell, and the plausible outcomes of cellular response in fighting against DNA damage.

Repair of a mal-repaired biliary injury:A case report

Iatrogenic bile-duct injury post-laparoscopic cholecystectomy remains a major serious complication with unpredictable long-term results. We present a patient who underwent laparoscopic cholecystectomy for gallstones, in which the biliary injury was recognized intraoperatively. The surgical procedure was converted to an open one. The first surgeon repaired the injury over a T-tube without recognizing the anatomy and type of the biliary lesion, which led to an unusual biliary mal-repair. Immediately postoperatively, the abdominal drain brought a large amount of bile. A T-tube cholangiogram was performed. Despite the contrast medium leaking through the abdominal drain, the mal-repair was recognized intraoperatively. The surgical procedure was converted to an open one. The first surgeon repaired the injury over a T-tube without recognizing the anatomy and type of the biliary lesion, which led to an unusual biliary mal-repair. Immediately postoperatively, the abdominal drain brought a large amount of bile. A T-tube cholangiogram was performed. Despite the contrast medium leaking through the abdominal drain, the mal-repair was unrecognized. The patient was referred to our hospital for biliary leak. Ultrasound and cholangiography was repeated, which showed an unanatomical repair （right to left hepatic duct anastomosis over the T-tube）,with evidence of contrast medium coming out through the abdominal drain. Eventually the patient was subjected to a definitive surgical treatment. The biliary continuity was re-established by a Roux-en-Y hepaticojejunostomy, over transanastomotic external biliary stents. The patient is now doing well 4 years after the second surgical procedure. In reviewing the literature, we found a similar type of injury but we did not find a similar surgical real-repair. We propose an algorithm for the treatment of early and late biliary injuries.

Modified Predator-Prey Model for Mealybug Population with Biological Control

Mealybugs are a major pest for many crops （such as the vegetable Cassava, in Thailand）. An environmentally-friendly bio-control method is implemented using an introduced predator （green lacewings） of the mealybugs to mitigate plant damage. This is analyzed so as to devise and determine an optimal strategy for control of the mealybug population. A predator-prey model has been proposed and analyzed to study the effect of the biological control of the spread of the mealybugs in the plant field. The behaviour of the system in terms of stability, phase space and bifurcation diagrams are considered. The results obtained from different numbers of predators being released are compared. In particular we obtain thresholds of introduced-predator level above which the prey is driven to extinction. Future models will include age-structured multi-compartments for both the prey and predator populations.

Effects of UV-B radiation on tetraspores of Chondrus ocellatus Holm(Rhodophyta),and effects of red and blue light on repair of UV-B-induced damage

We evaluated the effects of red and blue light on the repair of UV-B radiation-induced damage in tetraspores of Chondrus ocellatus Holm. Tetraspores of C. ocellatus were treated with different UV-B radiation levels(0,36,72,108,144 and 180 J/m2),and thereafter subjected to PAR,darkness,or red or blue light during a 2-h repair stage,each day for 48 days. The diameters and cellular contents of cyclobutane pyrimidine dimmers(CPDs),chlorophyll a(Chl a),phycoerythrin,and UV-B-absorbing mycosporinelike amino acids(MAAs) contents of the tetraspores were determined. Our results show that low doses of UV-B radiation(36 and 72 J/m 2) promoted the growth of C. ocellatus; however,increased UV-B radiation gradually reduced the C. ocellatus growth(greater than 72 J/m2). The MAAs(palythine and asterina-330) in C. ocellatus were detected and analyzed by LC/MS. Our results suggest that moderate red light could induce the growth of this alga in aquaculture. In addition,photorepair was inhibited by red light,so there may be some other DNA repair mechanism activated by red light. Blue light promoted the activity of DNA photolyase,greatly improving remediation efficiency. Red and blue lights were found to reduce the capacity of C. ocellatus to form MAAs. Therefore,PAR,red light,and blue light play different roles during the repair processes for damage induced by UV-B radiation.