2000 PPI silicon-based AlGaInP red micro-LED arrays fabricated via wafer bonding and epilayer lift-off.

In this article, 2000 PPI red silicon-based AlGaInP micro-LED arrays were fabricated and investigated. The AlGaInP epilayer was transferred onto the silicon substrate via the In-Ag bonding technique and an epilayer lift-off process. The silicon substrate with a high thermal conductivity could provide satisfactory heat dissipation, leading to micro-LED arrays that had a stable emission spectrum with increasing current density from 20 to 420 A/cm2 along with a red-shift of the peak position from 624.69 to 627.12 nm (Δλ = 2.43 nm). Additionally, increasing the injection current density had little effect on the CIE (x, y) of the micro-LED arrays. Further, the I-V characteristics and light output power of micro-LED arrays with different pixel sizes demonstrated that the AlGaInP red micro-LED array on a silicon substrate had excellent electrical stability and optical output.

Comparative analysis and optimization of protocols for producing recombinant lentivirus carrying the anti-Her2 chimeric antigen receptor gene.

BACKGROUND: The production of anti-Her2 chimeric antigen receptor (CAR) T cells needs to be optimized to make it a reliable therapy. METHODS: Three types of lentiviral vectors expressing anti-Her2 CAR together with packaging plasmids were co-transfected into 293 T-17 cells. The vector with the best packaging efficiency was selected, and the packaging cell culture system and packaging plasmid system were optimized. Centrifugation speed was optimized for the concentration of lentivirus stock. The various purification methods used included membrane filtration, centrifugation with a sucrose cushion and the novelly-designed instantaneous high-speed centrifugation. The recombinant lentiviruses were transduced into human peripheral T cells with an optimized multiplicity of infection (MOI). CAR expression levels by three vectors and the efficacy of CAR-T cells were compared. RESULTS: When co-transfected, packaging cells in suspension were better than the commonly used adherent culture condition, with the packaging system psPAX2/pMD2.G being better than pCMV-dR8.91/pVSV-G. The optimal centrifugation speed for concentration was 20 000 g, rather than the generally used ultra-speed. Importantly, adding instantaneous centrifugation for purification significantly increased human peripheral T cell viability (from 13.25% to 62.80%), which is a technical breakthrough for CAR-T cell preparation. The best MOI value for transducing human peripheral T cells was 40. pLVX-EF1a-CAR-IRES-ZsGreen1 expressed the highest level of CAR in human peripheral T cells and the cytotoxicity of CAR-T cells reached 63.56%. CONCLUSIONS: We optimized the preparation of recombinant lentivirus that can express third-generation anti-Her2 CAR in T cells, which should lay the foundation for improving the efficacy of CAR-T cells with respect to killing target cells.

Microfluidic static droplet generated quantum dot arrays as color conversion layers for full-color micro-LED displays.

This paper presents an easy and intact process based on microfluidics static droplet array (SDA) technology to fabricate quantum dot (QD) arrays for full-color micro-LED displays. A minimal sub-pixel size of 20 µm was achieved, and the fluorescence-converted red and green arrays provide good light uniformity of 98.58% and 98.72%, respectively.

Erratum: Overcome trastuzumab resistance of breast cancer using anti-HER2 chimeric antigen receptor T cells and PD1 blockade.

[This corrects the article on p. 688 in vol. 10, PMID: 32195036.].

Micropore filling fabrication of high resolution patterned PQDs with a pixel size less than 5 µm.

PQDs are promising color converters for micro-LED applications. Here we report the micropore filling fabrication of high resolution patterned PQDs with a pixel size of 2 µm using a template with SU8 micropores.

Flexible Quantum-Dot Color-Conversion Layer Based on Microfluidics for Full-Color Micro-LEDs.

In this article, red and green perovskite quantum dots are incorporated into the pixels of a flexible color-conversion layer assembly using microfluidics. The flexible color-conversion layer is then integrated with a blue micro-LED to realize a full-color display with a pixel pitch of 200 µm. Perovskite quantum dots feature a high quantum yield, a tunable wavelength, and high stability. The flexible color-conversion layer using perovskite quantum dots shows good luminous and display performance under different bending conditions; is easy to manufacture, economical, and applicable; and has important potential applications in the development of flexible micro-displays.

Comparative analysis of the autism­related variants between different autistic children in a family pedigree.

The present study aimed to provide evidence for the genetic heterogeneity of familial autism spectrum disorder (ASD), which might help to improve our understanding of the complex polygenic basis of this disease. Whole­exome sequencing (WES) was performed on two autistic children in a family pedigree, and reasonable conditions were set for preliminarily screening variant annotations. Sanger sequencing was used to verify the preliminarily screened variants and to determine the possible sources. In addition, autism­related genes were screened according to autism databases, and their variants were compared between two autistic children. The results showed that there were 21 genes respectively for autistic children â…£2 and â…£4, preliminarily screened from all variants based on the harmfulness (high) and quality (high or medium) of the variants, as well as the association between mutant genes and autism in human gene mutation database. Furthermore, candidate autism­related genes were screened according to the evidence score of >4 in the Autism KnowledgeBase (AutismKB) database or ≥3 in the AutDB database. A total of 11 and 10 candidate autism­related genes were identified in the autistic children â…£2 and Ⅳ4, respectively. Candidate genes with an evidence score of >16 in AutismKB were credible autism­related genes, which included LAMC3, JMJD1C and CACNA1H in child Ⅳ2, as well as SCN1A, SETD5, CHD7 and KCNMA1 in child â…£4. Other than the c.G1499A mutation of SCN1A, which is known to be associated with Dravet syndrome, the specific missense variant loci of other six highly credible putative autism­related genes were reported for the first time, to the best of the authors' knowledge, in the present study. These credible autism­related variants were inherited not only from immediate family members but also from extended family members. In summary, the present study established a reasonable and feasible method for screening credible autism­related genes from WES results, which by be worth extending into clinical practice. The different credible autism­related genes between the two autistic children indicated a complex polygenic architecture of ASD, which may assist in the early diagnosis of this disease.

The Third Generation Anti-HER2 Chimeric Antigen Receptor Mouse T Cells Alone or Together With Anti-PD1 Antibody Inhibits the Growth of Mouse Breast Tumor Cells Expressing HER2 in vitro and in Immune Competent Mice.

Chimeric Antigen Receptor (CAR)-T cells have great efficacy against CD19+ leukemia but little success for solid tumors. This study explored the effectiveness of third generation anti-HER2 CAR-T cells alone or in combination with anti-PD1 antibody on breast tumor cells expressing HER2 in vitro and in immune competent mouse model. The PDL1-positive mouse mammary tumor cell line 4T1 engineered to express luciferase and human HER2 was used as the target cell line (4T1-Luc-HER2). Anti-HER2 CAR-T cells were generated by transducing mouse spleen T cells with recombinant lentiviruses. ELISA analysis showed that IL-2 and IFN-γ secretion was increased in CAR-T cells co-cultured with the target cells, and the secretion of these two cytokines was increased further with the addition of anti-PD1 antibody. Lactate dehydrogenase assay revealed that CAR-T cells displayed a potent cytotoxicity against the target cells, and the addition of anti-PD1 antibody further enhanced the cytotoxicity. At the effector: target ratio of 16:1, cytotoxicity was 39.8% with CAR-T cells alone, and increased to 49.5% with the addition of anti-PD1 antibody. In immune competent syngeneic mouse model, CAR-T cells were found to be present in tumor stroma, inhibited tumor growth and increased tumor apoptosis significantly. Addition of anti-PD1 antibody further enhanced these anti-tumor activities. Twenty-one days after treatment, tumor weight was reduced by 50.0% and 73.3% in CAR-T group and CAR-T plus anti-PD1 group compared with blank T group. Our results indicate that anti-PD1 antibody can greatly increase the efficacy of anti-HER2 CAR-T against HER2-positive solid tumors.

Overcome trastuzumab resistance of breast cancer using anti-HER2 chimeric antigen receptor T cells and PD1 blockade.

Trastuzumab-resistance is still a major challenge in treating patients with HER2 positive breast cancer. In this study, we tried to overcome transtuzumab-resistance by examining the therapeutic efficacy of third generation anti-HER2 chimeric antigen receptor (CAR)-T cells alone and in combination with PD1 blockade against HER2 positive and trastuzumab-resistance breast cancer cells in vitro and xenograft model. The anti-HER2 CAR-T cells were generated by infecting CD3/CD28 activated peripheral blood mononuclear cells with lentivirus expressing third generation anti-HER2 CAR. Anti-HER2 CAR-T cells were specifically targeted to HER2 positive BT474 and trastuzumab resistant HCC1954 cells compared with HER2 negative breast cancer cells. Results from ELISA revealed that the secretion of IL-2 and IFN-γ was increased in anti-HER2 CAR-T cells after being co-cultured with HCC1954 cells, and was further increased with the addition of anti-PD1 antibody in the co-culture system. Furthermore, data from lactate dehydrogenase assay showed that anti-HER2 CAR-T cells displayed a potent cytotoxicity against HCC1954 and BT474 cells. Addition of anti-PD1 antibody further enhanced the cytotoxicity of anti-HER2 CAR-T cells against HCC1954 cells. Lastly, injection of anti-HER2 CAR-T cells significantly reduced the growth of HCC1954 xenograft tumors. Combining anti-HER2 CAR-T cells with anti-PD1 antibody further impaired the growth of HCC1954 tumors. The present results indicate that anti-HER2 CAR-T cells have therapeutic efficacy against trastuzumab resistant breast tumors and addition of the PD1 antibody can further enhance the therapeutic effect of anti-HER2 CAR-T cells. Thus, third generation anti-HER2 CAR-T cells along with PD1 blockade is a potential therapy to overcome trastuzumab resistance of breast cancer.

The efficacy of third generation anti­HER2 chimeric antigen receptor T cells in combination with PD1 blockade against malignant glioblastoma cells.

Without effective treatment, glioblastoma is one of the deadliest cancers worldwide. The aim of the present study was to explore whether combinational immunotherapy is effective for treating malignant glioblastoma in vitro. The therapeutic efficacy of third generation anti­human epidermal growth factor receptor 2 (HER2) chimeric antigen receptor (CAR)­T cells alone and in combination with PD1 blockade was investigated for the treatment of malignant glioblastoma cells in vitro. Anti­HER2 CAR­T cells were prepared by transducing activated primary human T cells with lentiviruses which expressed third generation anti­HER2 CAR. The CAR­positive cell ratio was detected using flow cytometry. The expression level of CAR was detected by western blot analysis. The binding of anti­HER2 CAR­T cells to HER2+ U251 glioblastoma cells was examined under a fluorescence microscope. The cytokine secretion of CAR­T cells induced by target cells was analyzed via ELISA. The cytotoxicity of anti­HER2 CAR­T cells alone or in combination with anti­programmed death­1 (PD1) antibody against HER2+/PDL1+ U251 cells was examined using an LDH assay. The CAR­positive cell ratio and expression level of CAR in prepared CAR­T cells were both high enough. Anti­HER2 CAR­T cells could specifically bind to U251 cells. The IL­2 and IFN­Î³ secretion of CAR­T cells increased after being co­cultured with U251 cells, and further increased in the presence of anti­PD1 antibody. Anti­HER2 CAR­T cells displayed a potent cytotoxicity against U251 cells. In addition, the presence of anti­PD1 antibody further enhanced the efficacy of anti­HER2 CAR­T cells against U251 cells. The present results indicated that blocking PD1 immuno­suppression can increase the activation of CAR­T cells after they are activated by a targeting antigen. Third generation anti­HER2 CAR­T cells along with PD1 blockade have a great therapeutic potential for combatting malignant glioblastoma.

[The key points of prevention for special surgical complications after radical operation of gastric cancer].

Incidence of gastric cancer is high in China and standard radical operation is currently the main treatment for gastric cancer. Postoperative complications, especially some special complications, can directly affect the prognosis of patients, even result in the increase of mortality. But the incidences of these special complications are low, so these complications are often misdiagnosed and delayed in treatment owing to insufficient recognition of medical staff. These special complications include (1) Peterson hernia: It is an abdominal hernia developed in the space between Roux loop and transverse colon mesentery after Roux-Y reconstruction of digestive tract. Peterson hernia is rare and can quickly result in gangrenous ileus. Because of low incidence and without specific clinical symptoms, this hernia does not attract enough attention in clinical practice, so the outcome will be very serious. Once the diagnosis is made, an emergent operation must be performed immediately. Peterson space should be closed routinely in order to avoid the development of hernia. (2) Lymphatic leakage: It is also called chyle leakage. Cisterna chylus is formed by gradual concentration of extensive lymphatic net to diaphragm angle within abdominal cavity. Lymphadenectomy during operation may easily damage lymphatic net and result in leakage. The use of ultrasonic scalpel can decrease the risk of lymphatic leakage in certain degree. If lymphatic leakage is found during operation, transfixion should be performed in time. Treatment includes total parenteral nutrition, maintenance of internal environment, supplement of protein, and observation by clamp as an attempt. (3)Duodenal stump leakage: It is one of serious complications affecting the recovery and leading to death after subtotal gastrectomy. Correct management of duodenal stump during operation is one of key points of the prevention of duodenal stump leakage. Routine purse embedding of duodenal stump is recommend during operation. The key treatment of this complication is to promt diagnosis and effective hemostasis.(4) Blood supply disorder of Roux-Y intestinal loop: Main preventive principle of this complication is to pay attention to the blood supply of vascular arch in intestinal edge. (5) Anastomotic obstruction by big purse of jejunal stump: When Roux-en-Y anastomosis is performed after distal radical operation for gastric cancer, anvil is placed in the remnant stomach and anastomat from distal jejunal stump is placed to make gastrojejunal anastomosis, and the stump is closed with big purse embedding. The embedding jejunal stump may enter gastric cavity leading to internal hernia and anastomotic obstruction. We suggest that application of interruptable and interlocking suture and fixation of stump on the gastric wall can avoid the development of this complication.

High-performance multilayer composite membranes with mussel-inspired polydopamine as a versatile molecular bridge for CO2 separation.

It is desirable to develop high-performance composite membranes for efficient CO2 separation in CO2 capture process. Introduction of a highly permeable polydimethylsiloxane (PDMS) intermediate layer between a selective layer and a porous support has been considered as a simple but efficient way to enhance gas permeance while maintaining high gas selectivity, because the introduced intermediate layer could benefit the formation of an ultrathin defect-free selective layer owing to the circumvention of pore penetration phenomenon. However, the selection of selective layer materials is unfavorably restricted because of the low surface energy of PDMS. Various highly hydrophilic membrane materials such as amino group-rich polyvinylamine (PVAm), a representative facilitated transport membrane material for CO2 separation, could not be facilely coated over the surface of the hydrophobic PDMS intermediate layer uniformly. Inspired by the hydrophilic nature and strong adhesive ability of polydopamine (PDA), PDA was therefore selected as a versatile molecular bridge between hydrophobic PDMS and hydrophilic PVAm. The PDA coating endows a highly compatible interface between both components with a large surface energy difference via multiple-site cooperative interactions. The resulting multilayer composite membrane with a thin facilitated transport PVAm selective layer exhibits a notably enhanced CO2 permeance (1887 GPU) combined with a slightly improved CO2/N2 selectivity (83), as well as superior structural stability. Similarly, the multilayer composite membrane with a hydrophilic CO2-philic Pebax 1657 selective layer was also developed for enhanced CO2 separation performance.