A novel nucleic acid linker for multi-gene expression enhances plant and animal synthetic biology.

The production of compact vectors for gene stacking is hindered by a lack of effective linkers. Here, we report that a 26-nt nucleic acid linker, NAL1, from the fungus Glarea lozoyensis and its truncated derivatives could connect two genes as a bicistron, enabling independent translation in a maize protoplast transient expression system and human 293 T cells. The optimized 9-nt NAL10 linker was then used to connect four genes driven by a bidirectional promoter; this combination was successfully used to reconstruct the astaxanthin biosynthesis pathway in transgenic maize. The short and efficient nucleic acid linker NAL10 can be widely used in multi-gene expression and synthetic biology in animals and plants.

The evolution and formation of centromeric repeats analysis in Vitis vinifera.

MAIN CONCLUSION: Six grape centromere-specific markers for cytogenetics were mined by combining genetic and immunological assays, and the possible evolution mechanism of centromeric repeats was analyzed. Centromeric histone proteins are functionally conserved; however, centromeric repetitive DNA sequences may represent considerable diversity in related species. Therefore, studying the characteristics and structure of grape centromere repeat sequences contributes to a deeper understanding of the evolutionary process of grape plants, including their origin and mechanisms of polyploidization. Plant centromeric regions are mainly composed of repetitive sequences, including SatDNA and transposable elements (TE). In this research, the characterization of centromere sequences in the whole genome of grapevine (Vitis vinifera L.) has been conducted. Five centromeric tandem repeat sequences (Vv1, Vv2, Vv5, Vv6, and Vv8) and one long terminal repeat (LTR) sequence Vv24 were isolated. These sequences had different centromeric distributions, which indicates that grape centromeric sequences may undergo rapid evolution. The existence of extrachromosomal circular DNA (eccDNA) and gene expression in CenH3 subdomain region may provide various potential mechanisms for the generation of new centromeric regions.

Prognostic value and immunological role of PD-L1 gene in pan-cancer.

OBJECTIVE: PD-L1, a target of immune checkpoint blockade, has been proven to take the role of an oncogene in most human tumors. However, the role of PD-L1 in human pan-cancers has not yet been fully investigated. MATERIALS AND METHODS: Pan-cancer analysis was conducted to analyze expression, genetic alterations, prognosis analysis, and immunological characteristics of PD-L1. Estimating the correlation between PD-L1 expression and survival involved using pooled odds ratios and hazard ratios with 95% CI. The Kaplan-Meier (K-M) technique, COX analysis, and receiver operating characteristic (ROC) curves were applied to the survival analysis. Additionally, we investigated the relationships between PD-L1 and microsatellite instability (MSI), tumor mutational burden (TMB), DNA methyltransferases (DNMTs), the associated genes of mismatch repair (MMR), and immune checkpoint biomarkers using Spearman's correlation analysis. Also, immunohistochemical analysis and qRT-PCR were employed in evaluating PD-L1's protein and mRNA expression in pan-caner. RESULTS: PD-L1 showed abnormal mRNA and protein expression in a variety of cancers and predicted prognosis in cancer patients. Furthermore, across a variety of cancer types, the aberrant PD-L1 expression was connected to the MSI, MMR, TMB, drug sensitivity, and tumor immune microenvironment (TIME). Moreover, PD-L1 was significantly correlated with infiltrating levels of immune cells (T cell CD8 + , neutrophil, and so on). CONCLUSION: Our study provides a better theoretical basis and guidance for the clinical treatment of PD-L1.

Rare retroperitoneal giant sacral schwannoma: A case report.

Schwannomas localized in the sacrum are relatively infrequent, accounting for 1-5% of all spinal axis schwannomas; they present with vague symptoms or are symptomless, so often grow to a considerable size before detection. Sacral schwannomas occasionally present with enormous dimensions, and these tumors are termed giant sacral schwannomas. However, their surgical removal is challenging owing to an abundant vascularity. The present study retrospectively analyzed the clinical and follow-up data of a patient with a giant sacral schwannoma. The patient experienced numbness in the left buttock and lower extremity, with radiating pain in the sole of the foot that had persisted for 3 years. A presacral mass was found by computed tomography examination 6 months after the stool had become thin. A tumor resection was performed using the anterior abdominal approach. A schwannoma was diagnosed by postoperative pathology. The postoperative course was uneventful, with the complete resolution of symptoms during the 21-month clinical follow-up. Overall, the present study reports the case of a giant sacral schwannoma with pelvic pain that was resected without complications and also discusses its successful management. Additionally, the study presents a systematic review of the literature. We consider that the surgical treatment of giant sacral schwannomas with piecemeal subtotal excision can achieve good outcomes, avoiding unnecessary neurological deficits.

Placement of a drainage tube in the ileac lumen following laparoscopic appendectomy: A case report and literature review.

RATIONALE: Ileal perforation caused by the insertion of a drainage tube is a rare complication. Hence, the utilization of surgical drains in abdominal surgery remains controversial. At present, there is a trend to reduce the utilization of drains in abdominal surgery, although certain situations may necessitate their application. PATIENT CONCERNS: A 25-year-old Chinese woman presented with a history of right lower abdominal pain persisting for 10 days. Imaging examinations, including abdominal computed tomography and ultrasound, identified low-density lesions measuring 10 × 8 × 8cm3 in the right lower abdomen, which are consistent with perforated appendicitis complicated by a peri-appendiceal abscess. A laparoscopic appendectomy was carried out. On the 5th postoperative day, the drainage fluid changed to a grass-green color (80mL). Imaging with retrograde contrast through the drainage tube revealed that the 26 Fr silicon rubber drainage tube tip was positioned 50cm away from the ileocecal junction within the ileum. Both the ileal and ileocecal regions appeared well-developed. INTERVENTION AND OUTCOMES: Oral intake was suspended, and the patient received antacids, somatostatin, antibiotics, and total parenteral nutrition. On the 19th postoperative day, a follow-up imaging procedure using retrograde contrast through the drainage tube indicated that the tube tip was sealed. The treatment concluded on day 33 postoperatively, and the patient was discharged. DISCUSSION AND CONCLUSION: Ileal perforation due to an abdominal drainage tube following laparoscopic appendectomy constitutes a rare but serious complication. However, due to the adhesion and inflammatory changes around the abscess, laparoscopic dissection becomes a challenging and risky process, and the surgical skills and experiences are particularly important. Removing the abdominal drainage tube promptly based on the characteristics of the drainage fluid is recommended. The findings provide valuable insights for surgeons navigating similar challenges.

[Effects of Sophora japonica extract on alveolar bone mass in ovariectomized osteoporosis mice].

PURPOSE: To investigate the effect of Sophora japonica extract on alveolar bone mass in ovariectomized osteoporosis mice. METHODS: Six-week-old female non-pregnant wild-type C57BL/6J mice were randomly divided into sham operation group, ovariectomy(OVX) group and OVX+Sophora japonica extract group. Ovaries of the mice in the OVX group and the OVX+Sophora japonica extract group were removed, and the mice in the OVX+Sophora japonica extract group were treated by Sophora japonica extract at a dose of 150 mg/kg, three times a week for 4 weeks; while mice of the other two groups were given an equal volume of normal saline at the same time. Body weight was measured 3 times a week, and the micro-parameters of alveolar bone were detected by Micro-CT after 4 weeks. The data were analyzed by GraphPad Prism 9 software. RESULTS: Compared with the sham-operated group, the trabecular bone parameters of the alveolar bone in the OVX group were significantly decreased 1 month after operation (P＜0.05). One month after intervention with Sophora japonica extract, alveolar bone mineral density (BMD), trabecular number (Tb.N) and trabecular separation(Tb.Sp) in OVX mice was significantly rescued, with no significant difference compared to the sham surgery group(P＞0.05); but bone volume fraction(BV/TV) and trabecular thickness (Tb.Th) had not completely recovered to the levels of the sham-operated group(P＜0.05). CONCLUSIONS: Sophora japonica extract can effectively increase the alveolar bone mass reduced by estrogen deficiency and may be used as one of the potential drugs for the treatment of menopausal alveolar bone osteoporosis.

Shenmai Injection Alleviates Myocardial Ferroptosis via Activating the AKT1/mTOR Pathway in Rats with Acute Myocardial Infarction.

OBJECTIVE: Acute myocardial infarction (AMI) poses a serious burden on public health. Shenmai Injection (SMI) has been reported to have a cardioprotective effect and is used clinically attributed to its targeting of ferroptosis. This study aims to explore the underlying mechanisms of SMI in treating AMI through the application of network pharmacology analysis. METHODS: This study utilized network pharmacology to identify the bioactive ingredients and potential targets of SMI in treating AMI. A rat model of AMI was created by ligating the coronary arteries of rats, and a cell model was established by subjecting H9c2 cells to oxygen-glucose deprivation (OGD) to reveal the cardioprotective effects of SMI. Western blotting was employed to measure protein expressions, while hematoxylin-eosin staining was used to observe relevant pathological changes. Enzyme linked immunosorbent assay was conducted to measure the levels of biomarkers associated with cardiac injury and oxidative stress. RESULTS: A comprehensive analysis revealed a total of 225 putative targets of SMI in the context of AMI which exerted regulatory effects on numerous pathways and targeted multiple biological processes. AKT1 was identified as a core target mediating the effects of SMI on AMI by topological analysis. In vivo experiments revealed that SMI attenuated myocardial injury, oxidative stress, and ferroptosis in rats with AMI. Furthermore, SMI was found to enhance the expression levels of p-AKT1 and p-mTOR proteins in the myocardial tissues of rats afflicted with AMI. Similar findings were also observed in H9c2 cells subjected to OGD. Of particular interest, the suppression of OGD-induced iron accumulation, oxidative stress, and ferroptosis-associated proteins by SMI in H9c2 cells was reversed upon inhibition of the AKT1/mTOR pathway via MK2206. CONCLUSION: This study revealed that SMI exerts a protective effect against myocardial injury and ferroptosis caused by AMI via the activation of the AKT1/mTOR pathway.

The clinical outcome of pembrolizumab for patients with recurrent or metastatic squamous cell carcinoma of the head and neck: a single center, real world study in China.

Background: The KEYNOTE-048 and KEYNOTE-040 study have demonstrated the efficacy of pembrolizumab in recurrent or metastatic squamous cell carcinoma of the head and neck (R/M HNSCC), we conducted this real-world study to investigate the efficacy of pembrolizumab in patients with R/M HNSCC. Methods: This is a single-center retrospective study conducted in the Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (Shanghai, China). Between December 2020 and December 2022, a total of 77 patients with R/M HNSCC were included into analysis. The primary endpoint of the study was overall survival (OS), and the secondary endpoints were progression-free survival (PFS), overall response rate (ORR)and toxicity.Efficacy was assessed according to RECIST version 1.1.SPSS 27.0 and GraphPad Prism 8.0 software were utilized to perform the statistical analysis. Results: By the cut-off date (February 28, 2023), the median OS,PFS and ORR were 15.97 months,8.53 months and 48.9% in patients treated with the pembrolizumab regimen in the first line therapy. Among these patients, 17 patients received pembrolizumab with cetuximab,and 18 received pembrolizumab with chemotherapy.We observed no significant differences between two groups neither in median OS (13.9 vs 19.4 months, P=0.3582) nor PFS (unreached vs 8.233 months, P= 0.2807). In the ≥2nd line therapy (n=30), the median OS, PFS and ORR were 5.7 months, 2.58 months and 20% respectively. Combined positive score (CPS) was eligible from 54 patients. For first line therapy, the median OS and PFS were 14.6 and 8.53 months in patients with CPS ≥1, and median OS and PFS were 14.6 and 12.33 months in patients with CPS ≥20. The immune-related adverse events (irAEs) were occurred in the 31 patients (31/77, 40.26%), and the most common potential irAEs were hypothyroidism (25.97%), and pneumonitis (7.79%). Conclusion: Our real-world results indicated that pembrolizumab regimen is a promising treatment in patients with R/M HNSCC.