Withdrawn as duplicate: Post-yield softening of bending-dominated metal metamaterials.

This article has been withdrawn due to a publisher error that caused the article to be duplicated. The definitive version of this article is published under DOI https://doi.org/10.1210/pnasnexus/pgad075.

Post-yield softening of bending-dominated metal metamaterials.

Post-yield softening (PYS) plays an important role in guiding the design of high-performance energy-absorbing lattice materials. PYS is usually restricted to lattice materials that are stretching dominated according to the Gibson-Ashby model. Contrary to this long-held assumption, this work shows that PYS can also occur in various bending-dominated Ti-6Al-4V lattices with increasing relative density. The underlying mechanism for this unusual property is elucidated using the Timoshenko beam theory. It is attributed to the increase in stretching and shear deformation with increasing relative density, thereby increasing the tendency towards PYS. The finding of this work extends perspectives on PYS for the design of high-performance energy-absorbing lattice materials.

Safety and efficacy evaluation of laparoscopy in colorectal cancer with liver metastasis.

OBJECTIVE: To study the safety and efficacy of simultaneous completion of colorectal cancer resection and liver metastasis resection by total laparoscopy. PATIENTS AND METHODS: In the observation group, 40 patients with colorectal cancer combined with liver metastasis (CRCLM) were selected to receive total laparoscopic surgery. At the same time, 40 cases were selected for laparoscopic resection of colorectal cancer and hepatic resection as control group. RESULTS: The outcomes of the two methods in the treatment of CRCLM were compared. The results showed that the difference in surgery time between the two groups was not statistically significant (p>0.05). The blood loss, drainage tube retention time and anal exhaust recovery time in the observation group were significantly less than those in control group (p<0.05). No significant difference in completion rate was found between the two groups (p>0.05); the prevalence rate of complications in the observation group was significantly lower than that in control group (p<0.05). No significant differences in the median survival period and the survival rate at 1 year, 2 years and 3 years after surgery were found between the two groups (p>0.05). CONCLUSIONS: The outcomes of total laparoscopy in the treatment of CRCLM are not inferior to open surgery.

Fine structure characterization of martensite/austenite constituent in low-carbon low-alloy steel by transmission electron forward scatter diffraction.

Transmission electron forward scatter diffraction and other characterization techniques were used to investigate the fine structure and the variant relationship of the martensite/austenite (M/A) constituent of the granular bainite in low-carbon low-alloy steel. The results demonstrated that the M/A constituents were distributed in clusters throughout the bainitic ferrite. Lath martensite was the main component of the M/A constituent, where the relationship between the martensite variants was consistent with the Nishiyama-Wassermann orientation relationship and only three variants were found in the M/A constituent, suggesting that the variants had formed in the M/A constituent according to a specific mechanism. Furthermore, the Σ3 boundaries in the M/A constituent were much longer than their counterparts in the bainitic ferrite region. The results indicate that transmission electron forward scatter diffraction is an effective method of crystallographic analysis for nanolaths in M/A constituents.

Cancer targeting Gene-Viro-Therapy of liver carcinoma by dual-regulated oncolytic adenovirus armed with TRAIL gene.

Liver cancer is a common and aggressive malignancy, but available treatment approaches remain suboptimal. Cancer targeting Gene-Viro-Therapy (CTGVT) has shown excellent anti-tumor effects in a preclinical study. CTGVT takes advantage of both gene therapy and virotherapy by incorporating an anti-tumor gene into an oncolytic virus vector. Potent anti-tumor activity is achieved by virus replication and exogenous expression of the anti-tumor gene. A dual-regulated oncolytic adenoviral vector designated Ad·AFP·E1A·E1B (Δ55) (Ad·AFP·D55 for short thereafter) was constructed by replacing the native viral E1A promoter with the simian virus 40 enhancer/α-fetoprotein (AFP) composite promoter (AFPep) based on an E1B-55K-deleted construct, ZD55. Ad·AFP·D55 showed specific replication and cytotoxicity in AFP-positive hepatoma cells. It also showed enhanced safety in normal cells when compared with the mono-regulated vector ZD55. To improve the anti-hepatoma activities of the virus, the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene was introduced into Ad·AFP·D55. Ad·AFP·D55-TRAIL exhibited remarkable anti-tumor activities in vitro and in vivo. Treatment with Ad·AFP·D55-TRAIL can induce both autophagy owing to the Ad·AFP·D55 vector and caspase-dependent apoptosis owing to the TRAIL protein. Therefore, Ad·AFP·D55-TRAIL could be a potential anti-hepatoma agent with anti-tumor activities due to AFP-specific replication and TRAIL-induced apoptosis.

Adenovirus-mediated interleukin-2 gene therapy of nociception.

The effect of adenovirus-mediated interleukin-2 (IL-2) gene on rat basal nociceptive response and chronic neuropathic pain was explored. The paw withdrawal latency induced by radiant heat was used to evaluate the antinociceptive effect of adenovirus type 5 (Ad5) and Ad5-IL-2. The results showed that intrathecal delivery of Ad5-IL-2 exhibited obvious antinociceptive effects on basal nociceptive response and chronic neuropathic pain, which were maintained for 3 and 4 weeks, respectively. This suggested that the antinociceptive effect of Ad5-IL-2 on chronic neuropathic pain was greater than its effect on basal nociceptive response. Human IL-2 mRNA was detected by in situ hybridization in the spinal pia mater and parenchyma of the lumbar, sacral, thoracic and cervical regions, and gray matter had higher level of IL-2 expression than white matter. These data demonstrated that the IL-2 gene was transfected into spinal cord regions relevant to pain modulation. The expressed IL-2 protein profile in spinal cord detected by enzyme-linked immunosorbent assay coincided almost exactly with its antinociceptive effect. This supported the hypothesis that the therapeutic effect of IL-2 gene was related to IL-2 protein expression. The study indicates that intrathecal delivery of adenovirus-mediated IL-2 gene has a relatively long antinociceptive effect.

Interleukin-2 gene therapy of chronic neuropathic pain.

Previous research has revealed an antinociceptive (analgesic) effect of interleukin-2 (IL-2) in central and peripheral nervous systems. Unfortunately IL-2 is very short-lived in vivo, so it is impractical to apply IL-2 for analgesia in clinic. This study was performed to evaluate the effect of intrathecal delivery of human IL-2 gene on rat chronic neuropathic pain induced by chronic constriction injury of the sciatic nerve. Human IL-2 cDNA was cloned into pcDNA3 containing a cytomegalovirus promoter. The paw-withdrawal latency induced by radiant heat was used to measure the pain threshold. The results showed that recombinant human IL-2 had a dose-dependent antinociceptive effect, but that this only lasted for 10-25 min. The pcDNA3-IL-2 or pcDNA3-IL-2/lipofectamine complex in contrast also showed dose-dependent antinociceptive effects, but these reached a peak at day 2-3 and were maintained for up to 6 days. Liposome-mediated pcDNA3-IL-2 produced a more powerful antinociceptive effect than pcDNA3-IL-2 alone. The paw-withdrawal latencies were not affected by control treatments such as vehicle, lipofectamine, pcDNA3, or pcDNA3-lipofectamine. In the experimental groups, human IL-2 mRNA was detected by reverse transcription-polymerase chain reaction in the lumbar spinal pia mater, dorsal root ganglion, sciatic nerve, and spinal dorsal horn, but not in gastrocnemius muscle. The expressed IL-2 profile detected by western blot coincided with its mRNA profile except it was present in the spinal dorsal horn at a higher level. Furthermore, human IL-2 assayed by enzyme-linked immunosorbent assay in cerebrospinal fluid could still be detected at day 6, but lower than day 3. The antinociceptive effect of pcDNA3-IL-2 could be blocked by naloxone, showing some relationship of the antinociceptive effect produced by IL-2 gene to the opioid receptors. It is hoped that the new delivery approach of a single intrathecal injection of the IL-2 gene described here may be of some practical use as a part of a gene therapy for treating neuropathic pain.

[Experimental study of bone repair induced by cryopreserved allograft periosteum and fetal bone composition in bone defect].

OBJECTIVE: To investigate the repairing effect of transplantation of allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft to bone defect. METHODS: Twenty Long-eared white male rabbits were chosen as experimental model of bilateral 12 mm combined bony and periosteal radial defect. Cryopreserved allograft periosteum with allogeneic fetal bone were implanted in the left defect as experimental side and fetal bone was simply transplanted in the right defect as control side. Bone repair process in the two groups were compared by macroscopy, microscopy, roentgenograms and the contents of calcium and phosphate in the defect area at 2, 4, 8 and 12 weeks after transplantation. RESULTS: There was significant statistic difference in the contents of calcium and phosphate between the experimental and control sides at 4, 8 and 12 weeks after transplantation (P < 0.05). With time passing by, the contents of calcium and phosphate have the increasing trends. In the experimental group, lamella bone was seen and medullary canal recanalized at 8 weeks postoperatively. The histological section showed the bone lacuna and lamella bone were formed. CONCLUSION: It suggests that allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft can promote bone repair, and allogeneic fetal bone is excellent bone substitute.

[Progress on the study of neurochemical mechanisms of learning and memory].

Brain function research is one of the most important projects in biological sciences. Learning and memory is one of the most advanced functions in brain. This article reviewed the effects of some neurotransmitters and neuroactive peptides on learning and memory in an attempt to stimulate the research aiming at improving learning and memory.

[Effect of hypoxia on the growth and differentiation of NG108-15 cells].

The neuroblastoma x glioma hybrid clone NG108-15 which were derived by fusion of mouse neuroblastoma clone N18TG6 with rat glioma clone C6BU1 proliferates in the presence of fetal calf serum, but differentiates when intracellular cAMP concentration is made to increase by addition of dBcAMP to the cultural medium. After differentiation, the cells express many neural properties. In this experiment, by means of an automatic colorimetric microassay for quantifying the growth and Brilliant Cresyl Violett stain for revealing Nissl substance, the effect of hypoxia (2% O2) on the hybrid cells was investigated. The results obtained were as follows: (1) Hypoxia depressed proliferation of non-differentiated cells and induced death of differentiated ones. (2) Hypoxia inhibited differentiation, either non-differentiated or differentiating cells, in the direction to be a neuro-like cell: some cells became large flat with short processes and had no Nissl substance. Whether hypoxia would enable non-differentiated NG108-15 cells to differentiate in a direction to express more properties of glial cell is an interesting problem.

[The increase in endocytosis of mouse skeletal muscle after denervation and the proliferation of satellite cells].

The relationship between increase of endocytosis and proliferation of satellite cells in mouse skeletal muscle was studied by biochemical and culture methods in vitro. The results indicated that: (1) 4 d or 6 d after denervation, increase of endocytosis and proliferation of satellite cells in denervated muscle were induced. (2) Actinomycin D inhibited activation of satellite cells and endocytosis in normal muscle. (3) While in denervated muscle, actinomycin D inhibited proliferation of satellite cells as well as increase of endocytosis, but could not prevent muscle atrophy after denervation. These results imply that proliferation of satellite cells and increase of endocytosis in the muscle may concur to the appearance of some factors after denervation, or increase in endocytosis is a mere result of proliferation of satellite cells.

[Effect of anoxia on the growth of cultured neurons from embryonic chick forebrain].

Pure neurons from embryonic day 8 chick forebrain were cultured under anoxic condition (95% N2 and 5% CO2). After 24, 48 and 72 h in culture, MTT colorimetric microassay showed a reduced production of formazan, indicating that the neurons were seriously damaged. In addition, the glucose of the cultured media was significantly depleted. Even when glucose concentration was increased to 800-1,200 mg/100 ml, anoxia still caused neurons to die. The results indicate that brain neurons in embryo are sensitive to anoxia, and any protective influence of glia on anoxic neurons could not be mediated by supplying the latter with glycogen.

[Comparison of promoting the proliferation and fusion of myoblast between conditioned media from fibroblasts of chick embryo and fetal mouse].

Conditioned media were prepared by using the collected media which had cultured fibroblasts from muscle tissue of fetal mouse (ICR) or chick embryo (Leghorn chicken). The effects of these media on the proliferation and fusion in mouse or chick myoblast were studied quantitatively. The results were as follows: (1) the conditioned medium from fibroblasts of fetal mouse promoted the proliferation of mouse or chick embryonic myoblasts by 2.65 times (P less than 0.001) or 2.35 times (P less than 0.01) as compared with control groups respectively. (2) The conditioned medium from fibroblasts of embryonic chicken promoted the proliferation of chick or mouse embryonic myoblasts by 2.66 times (P less than 0.01) or 2.17 times (P less than 0.01) respectively. (3) The conditioned medium from fibroblasts of fetal mouse enhanced the fused rate of mouse or chick myoblasts by 1.9 or 2.6 times respectively. The conditioned medium from fibroblasts of embryonic chick enhanced the rate of chick myoblast fusion by 2.1 times, but the effect on the mouse myoblast fusion was not remarkable. The results suggest that the effect of fibroblast conditioned media on myoblast proliferation is similar in the two species, but the effect on the fusion of myoblasts is somewhat species-specific.