Virus-mimicking nanosystems: from design to biomedical applications

Nanomedicine, as an interdisciplinary discipline involving the development and application of nanoscale materials and technologies, is rapidly developing under the impetus of bionanotechnology and has attracted a great deal of attention from researchers. Especially, with the global outbreak of COVID-19, the in-depth investigation of the infection mechanism of the viruses has made the study of virus-mimicking nanosystems (VMNs) a popular research topic. In this review, we initiate with a brief historical perspective on the emergence and development of VMNs for providing a comprehensive view of the field. Next, we present emerging design principles and functionalization strategies for fabricating VMNs in light of viral infection mechanisms. Then, we describe recent advances in VMNs in biology, with a major emphasis on representative examples. Finally, we summarize the opportunities and challenges that exist in this field, hoping to provide new insights and inspiration to develop VMNs for disease diagnosis and treatment and to attract the interest of more researchers from different fields.

Effects of straw return with potassium fertilizer on the stem lodging resistance, grain quality and yield of spring maize (Zea mays L.)

This experiment aimed to study the effects of straw return combined with potassium fertilizer on stem lodging resistance, grain quality, and yield of spring maize. The objective was to provide a scientific basis for the rational utilization of Inner Mongolia spring maize straw and potassium fertilizer resources. The test material used was 'Xianyu 335', and the study was conducted in three ecological regions from east to west of Inner Mongolia (Tumochuan Plain Irrigation Area, Hetao Plain Irrigation Area, and Lingnan Warm Dry Zone). A split-plot design was employed, with the straw return method as the main plot and potassium fertilizer dosage as the secondary plot. We determined the stem resistance index, grain quality, and yield. The results showed that both straw return and potassium application improved stem lodging resistance, grain quality, and maize yield. Combining straw return with the reasonable application of potassium fertilizer enhanced the effectiveness of potassium fertilizer, increased lodging resistance, maize yield, and improved grain quality and yield stability. Under the straw return treatment, with potassium application compared to no potassium application, significant increases were observed in maize plant height, stem diameter, dry weight of stems, stem compressive strength, stem bending strength, grain protein content, yield, straw potassium accumulation content, and soil available potassium content. These increases were up to 30.79 cm, 2.63 mm, 15.40 g, 74.93 N/mm2, 99.65 N/mm2, 13.68%, 3142.43 kg/hm2, 57.97 kg/hm2, and 19.80 mg/kg, respectively. Therefore, the interaction of straw return and potassium fertilizer was found to be the most effective measure for maintaining high-yield and stress-resistant cultivation, improving grain quality, and optimizing the management of straw and potassium fertilizer resources. This approach is suitable for promotion and application in the spring maize growing areas of Inner Mongolia.

In-situ quantification of lipids in live cells through imaging approaches

Lipids are important molecules that are widely distributed within the cell, and they play a crucial role in several biological processes such as cell membrane formation, signaling, cell motility and division. Monitoring the spatiotemporal dynamics of cellular lipids in real-time and quantifying their concentrations in situ is crucial since the local concentration of lipids initiates various signaling pathways that regulate cellular processes. In this review, we first introduced the historical background of lipid quantification methods. We then delve into the current state of the art of in situ lipid quantification, including the establishment and utility of fluorescence imaging techniques based on sensors of lipid-binding domains labeled with organic dyes or fluorescent proteins, and Raman and magnetic resonance imaging (MRI) techniques that do not require lipid labeling. Next, we highlighted the biological applications of live-cell lipid quantification techniques in the study of in situ lipid distribution, lipid transformation, and lipid-mediated signaling pathways. Finally, we discussed the technical challenges and prospects for the development of lipid quantification in live cells, with the aim of promoting the development of in situ lipid quantification in live cells, which may have a profound impact on the biological and medical fields.

Real-Time Imaging of Single Viral mRNA Translation in Live Cells Using CRISPR/dCas13

Translation is one of the many critical cellular activities regulated by viruses following host-cell invasion, and studies of viral mRNA translation kinetics and subcellular localization require techniques for the dynamic, real-time visualization of translation. However, conventional tools for imaging mRNA translation often require coding region modifications that may affect native translation. Here, we achieve dynamic imaging of translation with a tool that labels target mRNAs with unmodified coding regions using a CRISPR/dCas13 system with specific complementary paired guide RNAs. This system enables a real-time dynamic visualization of the translation process and is a promising tool for further investigations of the mechanisms of translation.

Near-Infrared II Hemicyanine Dye with Large Stokes Shift Designed by TICT Regulation for Boosting Imaging-Guided Photothermal Therapy

The serious threat that cancer poses to human health highlights the significance of early detection and effective treatment. The integration of fluorescence diagnosis and photothermal therapy in NIR-II has gained attention due to its high sensitivity, fast response, and noninvasiveness. Fluorescence, produced by the radiative relaxation process of electrons in a molecule, and photothermal, generated by the nonradiative relaxation process of electrons in a molecule, are competing photophysical processes. Hence, it is a challenge for the molecule to balance between the properties of fluorescence and photothermal. In this study, a NIR-II hemicyanine with TICT character is designed to obtain molecules with both better fluorescence and photothermal properties, utilizing positively charged pyridine salt and triphenylamine as electron acceptor and donor, respectively, and oxole as the conjugated π-bridge. HCY-995, one of the synthesized compounds, has a quantum yield of 0.09%, photothermal conversion efficiency of 54.90%, and a significant Stoke shift of 232 nm, which makes it appropriate for the integration of photothermal therapy and high-resolution imaging. This study provides new insights into the development of NIR-II molecules with fluorescent and photothermal integrated properties.

A gas-selective Zn-MOF exhibits selective sensing of Fe3+ ions by doping with Tb3

Here, a new Zn2+ metal organic framework, {[Me2NH2][Zn2(L)(DTZ)]·2DMF·3H2O}n (Zn-MOF), has been synthesized with low-symmetric carboxylic acid ligand 2,6 bis(2',5'-dicarboxyphenyl)pyridine (H4L) as the main ligand and 3,5-diamino-1,2,4-riazole (DTZ) containing an electron-rich N atom as an auxiliary ligand. Because of its high structural stability and adsorption properties, it can be used to efficiently separate CO2/CH4 and C2H2/CH4. In addition, Tb@Zn-MOF was obtained by doping with Tb3+ to partially replace Zn2+. A study of its luminescence sensing performance demonstrated that Tb@Zn-MOF showed intense luminescence properties and can be used for the directional detection of Fe3+ in aqueous solution. Furthermore, PXRD analysis, UV-vis spectroscopy and X-ray photoelectron spectroscopy (XPS) were also used to study possible luminescence sensing mechanisms. The recognition mechanism for Fe3+ ions is believed to be caused by electron transfer.

[Clinical effects of free transplanted pre-expanded scapular flap in reconstructing scar contracture deformity of neck]

Objective: To investigate the clinical effects of free transplanted pre-expanded scapular flap in reconstructing scar contracture deformity of neck. Methods: A retrospective observational study was conducted. From February 2010 to August 2020, 17 cervical scar deformity patients (9 males and 8 females, aged 8-42 years) who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. The patients underwent skin and soft tissue expander (hereinafter referred to as expander) implantation in scapular region in stage Ⅰ procedures, and the free transplanted pre-expanded flaps were used to resurface the wounds followed by neck scar resection in the stage Ⅱ procedures. The wound size after neck scar release was 12.0 cm×6.0 cm-30.0 cm×24.0 cm, and the size of the flap ranged from 13.0 cm×7.5 cm to 31.5 cm×25.0 cm. The wounds in donor site of 15 patients were sutured directly, and the wounds in donor site of 2 patients were covered with full-thickness skin graft from abdominal area. The survival of flaps was observed after the operation of stage Ⅱ. Six months after stage Ⅱ surgery, Z plasty was performed to treat the incision scar contracture in 2 patients. For the 5 patients of overweight or bloating appearance in the 1/3 proximal flap underwent debulking procedures in 6-9 months after stage Ⅱsurgery. Before the stage Ⅰ surgery and six months after the last procedure (stage Ⅱ or stage Ⅲ), mental cervical angle (MCA) and cervical mandibular angle (CMA) were measured and the improvement of neck scar was evaluated by the angle values. The cervical motor function, skin color and texture in recipient areas, and scar in the donor sites assessed by Vancouver scar scale (VSS) were observed during follow-up. Data were statistically analyzed with paired sample t test. Results: After stage Ⅱ surgery, 15 patients' flaps survived well; venous crisis occurred in 2 flaps within 24 h after operation, and the flaps survived well after emergency exploration and thrombus removal+vascular re-anastomosis. Compared with the angle values of MCA of (126±12)° and CMA of (148±13)° of patients before the stage Ⅰ surgery, the angle values of MCA of (107±12)° and CMA of (123±11)° of patients in six months after the last procedure were significantly decreased (with t values of 10.68 and 6.54, respectively, P<0.05). After 2 years of follow-up, the patient's neck dorsiflexion, lateral bending, or other motor functions were not restricted; the color and texture of the flap in recipient site were close to those of the normal neck skin; the patient cases with VSS scores of scarring of 3, 4, 5, 6, and 7 were 1, 3, 7, 5, and 1 case, respectively. Conclusions: The free transplantation of the pre-expanded scapular flaps can provide sufficient tissue for wound coverage after the release of cervical scar contracture deformity; the expanded skin tissue is featured by thin soft tissue and good pliability, which is conducive to restore the neck appearance; the donor sites are relatively covert with less tension, therefore, the treatment is an effective method for correcting the contracture in the neck.

Label-free "signal-off" PEC aptasensor for determination of kanamycin based on 3D nanoflower-like FeIn2S4/CdS Z-scheme heterostructures

Highly photoactive 3D nanoflower-like FeIn2S4/CdS heterostructures were synthesized by hydrothermal treatment and low-temperature cation exchange. The FeIn2S4/CdS displayed 14.5 times signal amplification in contrast to FeIn2S4 alone. It was applied as a photoactive substrate to construct a label-free photoelectrochemical (PEC) aptasensor for ultrasensitive determination of kanamycin (KAN). Under the optimal conditions, the constructed PEC aptasensor displayed a wide linear range (5.0 × 10-4 ~ 5.0 × 101 ng mL-1) and a low detection limit (S/N = 3) of 40.01 fg mL-1. This study provides some constructive insights for preparation of advanced photoactive materials and exhibits great potential for quantitative determination of antibiotics in foods and environmental samples.

Engineered Lipidic Nanomaterials Inspired by Sphingomyelin Metabolism for Cancer Therapy

Sphingomyelin (SM) and its metabolites are crucial regulators of tumor cell growth, differentiation, senescence, and programmed cell death. With the rise in lipid-based nanomaterials, engineered lipidic nanomaterials inspired by SM metabolism, corresponding lipid targeting, and signaling activation have made fascinating advances in cancer therapeutic processes. In this review, we first described the specific pathways of SM metabolism and the roles of their associated bioactive molecules in mediating cell survival or death. We next summarized the advantages and specific applications of SM metabolism-based lipidic nanomaterials in specific cancer therapies. Finally, we discussed the challenges and perspectives of this emerging and promising SM metabolism-based nanomaterials research area.

[Effects of electroacupuncture pretreatment on long-term postoperative cognitive dysfunction and neuron-inflammation in aged rats]

OBJECTIVE

To observe the effects of electroacupuncture pretreatment on postoperative cognitive dysfunction (POCD), neuronal apoptosis and neuron-inflammation in aged rats.

METHODS

Thirty-six male SD rats aged 20 months were randomly divided into sham operation group, model group and electroacupuncture (EA) group, with 12 rats in each group. The POCD rats model was prepared by internal fixation of left tibial fracture. Five days before modeling, EA stimulation (2 Hz/15 Hz, 1 mA, 30 min) was applied to "Zusanli" (ST36), "Hegu" (LI4) and "Neiguan" (PC6) on the unaffected side of rats in the EA group, once a day for consecutive 5 d. The learning and memory abilities of rats were evaluated by water maze test 31-35 days after operation. The apoptosis of hippocampal neurons was observed by Tunel/NeuN double staining. The expressions of high mobility group protein B1 (HMGB1) and phosphorylated (p)-nuclear factor (NF)-κB in microglia cells in hippocampal dentate gyrus were detected by immunofluorescence staining. The expression levels of interleukin (IL)-6 and IL-1β in the hippocampus were detected by Western blot.

RESULTS

Compared with the sham operation group, the escape latency was prolonged (P<0.05); the frequency of crossing the original platform, ratio of the swimming distance and the time in the target quadrant of the Morris water maze were significantly decreased (P<0.05); the apoptosis rate of hippocampal neurons was significantly increased (P<0.05); the expressions of HMGB1 and p-NF-κB in microglia cells in the dentate gyrus and the expression levels of IL-6 and IL-1β in hippocampus were increased (P<0.05) in the model group. Compared with the model group, the results of the above indexes were all opposite (P<0.05) in the EA group.

CONCLUSION

EA preconditioning can regulate hippocampal inflammatory response, alleviate neuronal apoptosis rate and long-term cognitive dysfunction in aged rats with POCD, the mechanisms may be related to the inhibition of microglia HMGB1/NF-κB pathway in hippocampal dentate gyrus.

In Situ Self-Assembly of Fluorogenic RNA Nanozipper Enables Real-Time Imaging of Single Viral mRNA Translation

Real-time visualization of individual viral mRNA translation activities in live cells is essential to obtain critical details of viral mRNA dynamics and to detect its transient responses to environmental stress. Fluorogenic RNA aptamers are powerful tools for real-time imaging of mRNA in live cells, but monitoring the translation activity of individual mRNAs remains a challenge due to their intrinsic photophysical properties. Here, we develop a genetically encoded turn-on 3,5-difluoro-4-hydroxybenzylidene imidazolinone (DFHBI)-binding RNA nanozipper with superior brightness and high photostability by in situ self-assembly of multiple nanozippers along single mRNAs. The nanozipper enables real-time imaging of the mobility and dynamic translation of individual viral mRNAs in live cells, providing information on the spatial dynamics and translational elongation rate of viral mRNAs.

[Factors affecting BK polyomavirus infection after kidney transplantation in post-school children and a predictive infection model]

Objective: To analyze high-risk factors affecting BK polyomavirus (BKPyV) infection and to construct a prediction model for BKPyV infection in children after renal transplantation. Methods: The clinical data of 332 children who received allogeneic kidney transplantation in the First Affiliated Hospital of Zhengzhou University from January 2014 to March 2022 were retrospectively collected. According to the BKPyV load level, the dynamic change process of lymphocytes at different time points were analyzed. The factors that have potential influence on BKPyV infection were screened by Cox regression analysis, and the receiver operating characteristic curve (ROC) was used to evaluate the sensitivity and specificity of the predictive model of infection. Results: Among the 332 children, there were 215 males and 117 females; the age of transplantation was (12.2±3.9) years old; 37 cases were preschool (1-5 years old), and 295 cases were post-school age (6-18 years old). BKPyV load in 224 urine samples and 30 blood samples of children were detected. There were 9 cases of BKPyV-associated viruria and 3 cases of BKPyV associated viremia in pre-school children, 76 cases BKPyV associated viruria and 14 cases of BKPyV associated viremia in post-school children. Multivariate Cox regression analysis showed that higher body mass index (BMI) (HR=1.105, 95%CI: 1.020-1.197), antithyroglobulin (ATG) application (HR=2.196, 95%CI: 1.335-3.613), and higher tacrolimus concentration (HR=2.484, 95%CI: 1.298-4.753), higher natural killer (NK) lymphocyte count (HR=1.193, 95%CI: 1.009-1.411), higher CD14⁺⁺CD16^-cell count (HR=1.096, 95%CI: 1.024-1.173) were independent risk factors for BKPyV associated viruria in post-school children. Delayed graft function (DGF) (HR=4.993, 95%CI: 1.555-16.038), Acute rejection (AR) (HR=6.021, 95%CI: 1.930-18.787), higher CD14⁺⁺CD16^-cell count (HR=1.227, 95%CI: 1.081-1.392) were independent risk factors for BKPyV associated viremia in post-school children. The results of ROC curve analysis showed that combined BMI, immune induction drugs, tacrolimus concentration, NK cell count, and CD14⁺⁺CD16^-cell count predicted the occurrence of BKPyV associated viruria in post-school children after kidney transplantation at 0.5, 1, 2, and 5 years with area under curve (AUC) of 0.712 (95%CI: 0.626-0.798), 0.708 (95%CI: 0.612-0.804), 0.754 (95%CI: 0.668-0.840) and 0.767 (95%CI: 0.685-0.849). The sensitivity and specificity of the model were 64.9%, 61.4%, 61.6%, 55.8% and 70.9%, 72.4%, 76.0%, 84.0%, respectively. Combined with DGF, AR, and CD14⁺⁺CD16^-cell counts predicted the occurrence of BKPyV-associated viremia at 0.5, 1, 2, and 5 years after renal transplantation in post-school children with AUC of 0.791 (95%CI: 0.631-0.951), 0.744 (95%CI: 0.547-0.936), 0.786 (95%CI: 0.629-0.946) and 0.812 (95%CI: 0.672-0.948). The sensitivity and specificity of the model were 76.1%, 67.1%, 75.0%, 77.9% and 88.9%, 89.0%, 89.9%, 88.0%, respectively. Conclusions: The postoperative CD14⁺⁺CD16^-cell level can be used as an independent predictor of BKPyV infection in post-school children after renal transplantation. Combined BMI, immune induction drugs, tacrolimus concentration, NK cell count, CD14⁺⁺CD16^-cell count and combined DGF, AR, CD14⁺⁺CD16^-cell count show good fitting effect in predicting the occurrence of BKPyV-associated viruria and viremia after transplantation in post-school children respectively.

Artificial Cells for Cellular Behavior Mimicry Induced by Sphingomyelin Degradation

Sphingomyelinase (SMase), a hydrolase of sphingomyelin (SM) enriched in the outer leaflet of the plasma membrane of mammalian cells, is closely associated with the onset and development of many diseases, but the specific mechanisms of SMase on the cell structure, function, and behavior are not yet fully understood due to the complexity of the cell structure. Artificial cells are minimal biological systems constructed from various molecular components designed to mimic cellular processes, behaviors, and structures, which are excellent models for studying biochemical reactions and dynamic changes in cell membranes. In this work, we presented an artificial cell model that mimics the lipid composition and content of the outer leaflet of mammalian plasma membranes for studying the effect of SMase on cell behavior. The results confirmed that the artificial cells can respond to SM degradation by producing ceramides that enrich and alter the membrane charge and permeability, thus inducing the budding and fission of the artificial cells. Thus, the artificial cells developed here provide a powerful tool to study the mechanism of action of cell membrane lipids on cell biological behavior, paving the way for further molecular mechanism studies.

Purified fluorescent nanohybrids based on quantum dot-HER2-antibody for breast tumor target imaging

Quantum dots (QDs) have been widely used for bioimaging in vivo because of their excellent optical properties. As part of the preparation process of QD-based nanohybrids, purification is an important step for minimizing contaminants and improving the quality of the product. In this work, we describe high-performance size exclusion chromatography (HPSEC) used to purify nanohybrids of CdSe/ZnS QDs and anti-human epidermal growth factor receptor 2 antibodies (QD-HER2-Ab). The unbound antibody and suspended agglomerates were removed from freshly prepared QD-HER2-Ab via HPSEC. Pure and homogeneous QD-HER2-Ab were then used as immunofluorescence target imaging bioprobes in vivo. The QD-HER2-Ab did not cause any obvious acute toxicity in mice one week after a single intravenous injection of 15 nmol/kg. The purified QD-HER2-Ab bioprobes showed high tumor targeting ability in a human breast tumor xenograft nude mouse model (24 h after injected) with the possibility of in vivo immunofluorescence tumor imaging. The immunofluorescence imaging background signal and acute toxicity in vivo were minimized because of the reduction of residual QDs. HPSEC-purified QD-HER2-Ab is an accurate and convenient tool for in vivo tumor target imaging and HER2 detection, thus providing a basis for the purification of other QD-based bioprobes.

Nanocrystalline Alumina-Zirconia-Based Eutectic Ceramics Fabricated with High-Energy Beams: Principle, Solidification Techniques, Microstructure and Mechanical Properties

Nanocrystalline alumina-zirconia-based eutectic ceramics fabricated with high-energy beams and composed of ultrafine, three-dimensionally entangled, single-crystal domains are a special category of eutectic oxides that exhibit exceptionally high-temperature mechanical properties, such as strength and toughness as well as creep resistance. This paper aims to provide a comprehensive review on the basic principles, advanced solidification processes, microstructure and mechanical properties of alumina-zirconia-based eutectic ceramics, with particular attention to the status of the art on a nanocrystalline scale. Some basic principles of coupled eutectic growth are first introduced based on previously reported models, followed by concise introduction of solidification techniques and the control strategy of solidification behavior from the processing variables. Then, the microstructural formation of nanoeutectic structure is elucidated with regard to different hierarchical scales, and mechanical properties such as hardness, flexural and tensile strength, fracture toughness and wear resistance are discussed in detail for a comparative study. Nanocrystalline alumina-zirconia-based eutectic ceramics with unique microstructural and compositional characteristics have been produced with high-energy beam-based processes, and in many cases, promising improvements in mechanical performance have been reported as contrasting with conventional eutectic ceramics.

Characterization of a New Laccase from Vibrio sp. with pH-stability, Salt-tolerance, and Decolorization Ability

Laccases have been widely used for fruit juice clarification, food modification, and paper pulp delignification. In addition, laccases exhibit remarkable performance in the degradation of toxic substances, including pesticides, organic synthetic dyes, antibiotics, and organic pollutants. Thus, the screening and development of robust laccases has attracted significant attention. In this study, Vibrio sp. LA is a strain capable of producing cold-adapted laccases. The laccase coding gene L01 was cloned from this strain and expressed in Yarrowia lipolytica, a host with good secretion ability. The secreted L01 (approximate MW of 56,000 Da) had the activity and specific activity of 18.6 U/mL and 98.6 U/mg toward ABTS, respectively. The highest activity occurred at 35 °C. At 20 °C, L01 activity was over 70% of the maximum activity in pH conditions ranging from 4.5–10.0. Several synthetic dyes were efficiently degraded by L01. Owing to its robustness, salt tolerance, and pH stability, L01 is a promising catalytic tool for potential industrial applications.

[Clinical study of using basement membrane biological products in pelvic floor reconstruction during pelvic exenteration]

Objective: To investigate the value of reconstruction of pelvic floor with biological products to prevent and treat empty pelvic syndrome after pelvic exenteration (PE) for locally advanced or recurrent rectal cancer. Methods: This was a descriptive study of data of 56 patients with locally advanced or locally recurrent rectal cancer without or with limited extra-pelvic metastases who had undergone PE and pelvic floor reconstruction using basement membrane biologic products to separate the abdominal and pelvic cavities in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Military Medical University from November 2021 to May 2022. The extent of surgery was divided into two categories: mainly inside the pelvis (41 patients) and including pelvic wall resection (15 patients). In all procedures, basement membrane biologic products were used to reconstruct the pelvic floor and separate the abdominal and pelvic cavities. The procedures included a transperitoneal approach, in which biologic products were used to cover the retroperitoneal defect and the pelvic entrance from the Treitz ligament to the sacral promontory and sutured to the lateral peritoneum, the peritoneal margin of the retained organs in the anterior pelvis, or the pubic arch and pubic symphysis; and a sacrococcygeal approach in which biologic products were used to reconstruct the defect in the pelvic muscle-sacral plane. Variables assessed included patients' baseline information (including sex, age, history of preoperative radiotherapy, recurrence or primary, and extra-pelvic metastases), surgery-related variables (including extent of organ resection, operative time, intraoperative bleeding, and tissue restoration), post-operative recovery (time to recovery of bowel function and time to recovery from empty pelvic syndrome), complications, and findings on follow-up. Postoperative complications were graded using the Clavien-Dindo classification. Results: The median age of the 41 patients whose surgery was mainly inside the pelvis was 57 (31-82) years. The patients comprised 25 men and 16 women. Of these 41 patients, 23 had locally advanced disease and 18 had locally recurrent disease; 32 had a history of chemotherapy/immunotherapy/targeted therapy and 24 of radiation therapy. Among these patients, the median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to resolution of empty pelvic syndrome were 440 (240-1020) minutes, 650 (200-4000) ml, 3 (1-9) days, and 14 (5-105) days, respectively. As for postoperative complications, 37 patients had Clavien-Dindo < grade III and four had ≥ grade III complications. One patient died of multiple organ failure 7 days after surgery, two underwent second surgeries because of massive bleeding from their pelvic floor wounds, and one was successfully resuscitated from respiratory failure. In contrast, the median age of the 15 patients whose procedure included combined pelvic and pelvic wall resection was 61 (43-76) years, they comprised eight men and seven women, four had locally advanced disease and 11 had locally recurrent disease. All had a history of chemotherapy/ immunotherapy and 13 had a history of radiation therapy. The median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to relief of empty pelvic syndrome were 600 (360-960) minutes, 1600 (400-4000) ml, 3 (2-7) days, and 68 (7-120) days, respectively, in this subgroup of patients. Twelve of these patients had Clavien-Dindo < grade III and three had ≥ grade III postoperative complications. Follow-up was until 31 October 2022 or death; the median follow-up time was 9 (5-12) months. One patient in this group died 3 months after surgery because of rapid tumor progression. The remaining 54 patients have survived to date and no local recurrences have been detected at the surgical site. Conclusion: The use of basement membrane biologic products for pelvic floor reconstruction and separation of the abdominal and pelvic cavities during PE for locally advanced or recurrent rectal cancer is safe, effective, and feasible. It improves the perioperative safety of PE and warrants more implementation.

Bone marrow mesenchymal stem cells repress renal transplant immune rejection by facilitating the APRIL phosphorylation to induce regulation B cell production

Bone marrow mesenchymal stem cells (BMSCs) exert pivotal roles in suppressing immune rejection in organ transplantation. However, the function of BMSCs on immune rejection in renal transplantation remains unclear. This study aimed to evaluate the effect and underlying mechanism of BMSCs on immune rejection in renal transplantation. Following the establishment of the renal allograft mouse model, the isolated primary BMSCs were injected intravenously into the recipient mice. Enzyme-linked immunosorbent assay, flow cytometry, hematoxylin-eosin staining, and Western blot assays were conducted to investigate BMSCs' function in vivo and in vitro. Mechanistically, the underlying mechanism of BMSCs on immune rejection in renal transplantation was investigated in in vivo and in vitro models. Functionally, BMSCs alleviated the immune rejection in renal transplantation mice and facilitated B cell activation and the production of IL-10⁺ regulatory B cells (Bregs). Furthermore, the results of mechanism studies revealed that BMSCs induced the production of IL-10⁺ Bregs by facilitating a proliferation-inducing ligand (APRIL) phosphorylation to enhance immunosuppression and repressed renal transplant rejection by promoting APRIL phosphorylation to induce IL-10⁺ Bregs. BMSCs prevent renal transplant rejection by facilitating APRIL phosphorylation to induce IL-10⁺ Bregs.

[The prevalence and risk factors of diabetic peripheral artery disease in Chinese communities]

Objective: To investigate the prevalence and risk factors of diabetic peripheral artery disease (PAD) in patients with type 2 diabetes mellitus (T2DM) managed in primary health care in China. Methods: A total of 2 528 T2DM patients were selected using a two-stage cluster random sampling method based on the baseline survey of the "China Diabetic Foot Prevention Model Project." The study was conducted in 2015 among T2DM patients in 8 primary healthcare centers in Changshu county and Jiang'an district of Wuhan, China. Data collection methods included a questionnaire, body measurement, and blood glucose detection. The Ankle-Brachial Index (ABI) is the most widely used noninvasive vascular test. A binary logistic regression model was used to analyze the influence factors. Results: The prevalence of PAD was 11.2% among the diabetic patients managed in primary health care in the two cities. The prevalence of PAD under 55 years old, 55- years old, 65- years old, and ≥75 years old were 7.8%, 6.0%, 12.9% and 22.5%, respectively. Multivariate stepwise logistic regression identified influence factors included older age, higher education level, smoking, drinking, postprandial glucose uncontrol, and prior myocardial infarction or angina. Compared to age <55 years, the odds ratio for PAD were 0.74 for 55- years (95%CI: 0.43-1.28), 1.72 for 65- years (95%CI: 1.05-2.81), 3.56 for 75 years and above (95%CI: 2.07-6.11), respectively. Compared to patients with education in primary school and below, the odds ratio was 1.37 (95%CI: 0.97-1.94), 2.48 (95%CI: 1.73-3.55), 1.99 (95%CI: 1.26-3.13) for those with education levels of junior high school, senior high school, and college, respectively. Current smoking (OR=1.49, 95%CI: 1.02-2.17), current drinking (OR=0.45, 95%CI: 0.28-0.71), postprandial glucose uncontrol (2 h postprandial plasma glucose >10.0 mmol/L: OR=1.72, 95%CI: 1.22-2.43), and prior myocardial infarction or angina (OR=2.32, 95%CI: 1.50-3.61) were influencing factors of PAD. Conclusions: Despite the high prevalence of PAD in diabetes managed in primary health care; multiple risk factors are not effectively aware of and under control. It is urgent to promote ABI screening and standardized management for diabetes, especially in primary health care.

[Kinetics of SARS-CoV-2-specific antibodies among inactivated COVID-19 vaccine recipients, SARS-CoV-2 natural infection cases, and breakthrough cases]

Between August and September, 2021, this study included 605 SARS-CoV-2 natural infection cases and 589 SARS-CoV-2 breakthrough cases from Nanjing and Yangzhou, as well as 690 inactivated COVID-19 vaccine recipients from Changzhou, China. In SARS-CoV-2 natural infection cases, the age range was 19-91 years (median age: 66 year), and the medians(Q₁,Q₃) of IgG titers were 0.19 (0.06-1.31), 3.70 (0.76-69.48), 15.31 (2.59-82.16), 4.41 (0.99-31.74), 2.31 (0.75-13.83), 2.28 (0.68-9.94) and 2.80 (1.00-9.53) at one to seven weeks after SARS-CoV-2 infection, respectively. In SARS-CoV-2 breakthrough cases, the age range was 18-76 years (median age: 45 year), and the medians(Q₁,Q₃)of IgG titers were 1.93 (0.34-26.67), 38.87 (7.90-121.0), 75.09 (11.85-123.70), 21.97 (5.20-95.58), 13.97 (3.47-46.82), 9.56 (2.48-33.38) and 4.38 (1.87-11.00) at one to seven weeks after SARS-CoV-2 infection, respectively. In inactivated COVID-19 vaccine recipients, the age range was 18-87 years (median age: 47 years), and the medians(Q₁,Q₃)of IgG titers were 16.22 (15.84-33.42), 5.35 (2.96-13.23), 3.30 (2.18-6.18), 3.14 (1.16-5.70), 2.77 (1.50-4.52), 2.72 (1.76-4.36), 2.01 (1.27-3.51) and 1.94 (1.35-3.09) at one to eight months after SARS-CoV-2 infection, respectively. The results suggested that IgG antibodies increased gradually within two weeks after SARS-CoV-2 infection, then declined gradually at three to seven weeks in SARS-CoV-2 natural infection cases. In SARS-CoV-2 breakthrough cases, IgG antibodies increased rapidly within two weeks, then declined gradually at three to seven weeks after SARS-CoV-2 infection. Additionally, IgG antibodies decreased rapidly within three months, then decreased gradually and remained at a low level within three months after immunization.

Inducing Autophagy and Blocking Autophagic Flux via a Virus-Mimicking Nanodrug for Cancer Therapy

Maximizing the therapeutic capacity of drugs by allowing them to escape lysosomal degradation is a long-term challenge for nanodrug delivery. Japanese encephalitis virus (JEV) has evolved the ability to escape the endosomal region to avoid degradation of internal genetic material by lysosomes and further induce upregulation of cellular autophagy for the purpose of their mass reproduction. In this work, to exploit the lysosome escape and autophagy-inducing properties of JEV for cancer therapy, we constructed a virus-mimicking nanodrug consisting of anti-PDL1 antibody-decorated JEV-mimicking virosome encapsulated with a clinically available autophagy inhibitor, hydroxychloroquine (HCQ). Our study indicated that the nanodrug can upregulate the autophagy level and inhibit the autophagic flux, thereby inducing the apoptosis of tumor cells, and further activating the immune response, which can greatly improve the antitumor and tumor metastasis suppression effects and provide a potential therapeutic strategy for tumor treatment.