Construction of Dual-Active Sites by Interfacing with Polyhydroxy Fullerene on Nickel Hydroxide Surfaces to Promote CO2 Deep Photoreduction to CH4.

Due to the complex series of elementary steps involved, achieving deep photoreduction of CO2 to multielectron products such as CH4 remains a challenging task. Therefore, it is crucial to strategically design catalysts that facilitate the controlled formation of the crucial intermediates and provide precise control over the reaction pathway. Herein, we present a pioneering approach by employing polyhydroxy fullerene (PHF) molecules to modify the surface of Ni(OH)2, creating stable and effective synergistic sites to enhance the formation of CH4 from CO2 under light irradiation. As a result, the optimized PHF-modified Ni(OH)2 cocatalyst achieves a CH4 production rate of 455 µmol g-1 h-1, with an electron-based selectivity of approximately 60%. The combination of in situ characterizations and theoretical calculations reveals that the hydroxyl species on the surface of PHF can participate in stabilizing crucial intermediates and facilitating water activation, thereby altering the reaction pathway to form CH4 instead of CO. This study provides a novel approach to regulating the selectivity of photocatalytic CO2 reduction by exploring molecular surface modification through interfacing with functionalized carbon clusters.

A modular chemoenzymatic cascade strategy for the structure-customized assembly of ganglioside analogs.

Gangliosides play vital biological regulatory roles and are associated with neurological system diseases, malignancies, and immune deficiencies. They have received extensive attention in developing targeted drugs and diagnostic markers. However, it is difficult to obtain enough structurally defined gangliosides and analogs especially at an industrial-relevant scale, which prevent exploring structure-activity relationships and identifying drug ingredients. Here, we report a highly modular chemoenzymatic cascade assembly (MOCECA) strategy for customized and large-scale synthesis of ganglioside analogs with various glycan and ceramide epitopes. We typically accessed five gangliosides with therapeutic promising and systematically prepared ten GM1 analogs with diverse ceramides. Through further process amplification, we achieved industrial production of ganglioside GM1 in the form of modular assembly at hectogram scale. Using MOCECA-synthesized GM1 analogs, we found unique ceramide modifications on GM1 could enhance the ability to promote neurite outgrowth. By comparing the structures with synthetic analogs, we further resolved the problem of contradicting descriptions for GM1 components in different pharmaceutical documents by reinterpreting the exact two-component structures of commercialized GM1 drugs. Because of its applicability and stability, the MOCECA strategy can be extended to prepare other glycosphingolipid structures, which may pave the way for developing new glycolipid drugs.

Extralobar pulmonary sequestration: A case report and literature review.

Pulmonary sequestration is a congenital malformation of lung development in which part of the lung tissue is separated from the normal lung during the embryonic phase and develops separately and receives blood supply from an aberrant systemic artery forming a nonrespiratory mass. In brief, early in embryonic development, certain tissues that should have atrophied and been gradually absorbed are left behind due to impairment of the atrophy process and form anomalous branches of the aorta, which pull parts of the lung tissue, isolating them from normal lung tissue and bronchi, and thus forming separate lung tissue. According to the relationship of the mass to the pleural covering, pulmonary sequestration can be divided into two types, intralobar pulmonary sequestration (ILS) and extralobar pulmonary sequestration (ELS), of which approximately 75% of cases are ILS, but ELS is less common. Symptoms are not obvious in either type, making diagnosis and differential diagnosis more difficult. Here we report a 33-year-old patient with only insignificant abdominal distension who was eventually diagnosed with retroperitoneal ELS.

Campylobacter jejuni benefits from the bile salt deoxycholate under low-oxygen condition in a PldA dependent manner.

Enteric bacteria need to adapt to endure the antibacterial activities of bile salts in the gut. Phospholipase A (PldA) is a key enzyme in the maintenance of bacterial membrane homeostasis. Bacteria respond to stress by modulating their membrane composition. Campylobacter jejuni is the most common cause of human worldwide. However, the mechanism by which C. jejuni adapts and survives in the gut environment is not fully understood. In this study, we investigated the roles of PldA, bile salt sodium deoxycholate (DOC), and oxygen availability in C. jejuni biology, mimicking an in vivo situation. Growth curves were used to determine the adaptation of C. jejuni to bile salts. RNA-seq and functional assays were employed to investigate the PldA-dependent and DOC-induced changes in gene expression that influence bacterial physiology. Survival studies were performed to address oxidative stress defense in C. jejuni. Here, we discovered that PldA of C. jejuni is required for optimal growth in the presence of bile salt DOC. Under high oxygen conditions, DOC is toxic to C. jejuni, but under low oxygen conditions, as is present in the lumen of the gut, C. jejuni benefits from DOC. C. jejuni PldA seems to enable the use of iron needed for optimal growth in the presence of DOC but makes the bacterium more vulnerable to oxidative stress. In conclusion, DOC stimulates C. jejuni growth under low oxygen conditions and alters colony morphology in a PldA-dependent manner. C. jejuni benefits from DOC by upregulating iron metabolism in a PldA-dependent manner.

Case report: Obturator hernia: Diagnosis and surgical treatment.

Background: Obturator hernia (OH) is a rare external abdominal hernia, accounting for only 0.07%-1% of all hernia cases. Because the female pelvis is wider and there is less preperitoneal adipose tissue, the obturator canal is larger, which can lead to herniation of abdominal contents when abdominal pressure increases in elderly women with thin body. The clinical symptoms of patients with obturator hernia included abdominal pain, nausea, vomiting, etc., and the mass in the inguinal region could not be touched. The positive Howship-Romberg sign is a specific sign of OH. CT is the first choice for the diagnosis of obturator hernia. Since intestinal incarceration in OH patients is prone to lead to intestinal necrosis, emergency surgical treatment is often required. However, due to the lack of specificity of its clinical manifestations, the misdiagnosis rate is high, which often leads to the delay of diagnosis and treatment. Methods: We report the case of an 86-year-old woman with a thin body and a history of multiple deliveries. The patient presented with abdominal pain, bloating, and constipation for 5 days. Physical examination revealed a positive Howship-Romberg sign on the right side, and CT examination suggested intestinal obstruction. Therefore, an urgent exploratory laparotomy was performed. Results: After opening the abdominal cavity we found that the wall of the ileum was embedded in the right obturator, and the proximal bowel was significantly dilated. We restored the embedded bowel wall to its original position, resected the necrotic bowel and performed an end-to-end anastomosis of the small intestine. The right hernia orifice was sutured, and OH was diagnosed during the operation. Conclusion: This article summarizes the diagnosis and treatment of OH by sharing this case, so as to provide a more detailed plan for early diagnosis and treatment of OH.

SMC4, a novel tumor prognostic marker and potential tumor therapeutic target.

The structural maintenance of chromosome 4 (SMC4) is a member of the ATPase family of chromosomes. The most widely reported function of SMC4, as well as the remaining subunits of whole condensin complexes, is compression and dissociation of sister chromatids, DNA damage repair, DNA recombination, and pervasive transcription of the genome. Studies have also shown that SMC4 plays an exceedingly essential role in the division cycle of embryonic cells, such as RNA splicing, DNA metabolic process, cell adhesion, and extracellular matrix. On the other hand, SMC4 is also a positive regulator of the inflammatory innate immune response, while excessive innate immune responses not only disrupt immune homeostasis and may lead to autoimmune diseases, but even cancer. To further understand the expression and prognostic value of SMC4 in tumors, we provide an in-depth review of the literature and several bioinformatic databases, for example, The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Clinical Proteomic Tumor Analysis Consortium (CPTAC), The Human Protein Atlas and Kaplan Meier plotter tools, illustrating that SMC4 plays a vital role in the occurrence and development of tumors, and high expression of SMC4 seems to consistently predict worse overall survival. In conclusion, we present this review which introduces the structure, biological function of SMC4, and its correlation with the tumor in detail; it might provide new insight into a novel tumor prognostic marker and potential tumor therapeutic target.

Biological functions of bacterial lysophospholipids.

Lysophospholipids (LPLs) are lipid-derived metabolic intermediates in the cell membrane. The biological functions of LPLs are distinct from their corresponding phospholipids. In eukaryotic cells LPLs are important bioactive signaling molecules that regulate many important biological processes, but in bacteria the function of LPLs is still not fully defined. Bacterial LPLs are usually present in cells in very small amounts, but can strongly increase under certain environmental conditions. In addition to their basic function as precursors in membrane lipid metabolism, the formation of distinct LPLs contributes to the proliferation of bacteria under harsh circumstances or may act as signaling molecules in bacterial pathogenesis. This review provides an overview of the current knowledge of the biological functions of bacterial LPLs including lysoPE, lysoPA, lysoPC, lysoPG, lysoPS and lysoPI in bacterial adaptation, survival, and host-microbe interactions.

Avenanthramide-C Activates Nrf2/ARE Pathway and Inhibiting Ferroptosis Pathway to Improve Cognitive Dysfunction in Aging Rats.

Postoperative neurocognitive impairment (POCD) is a common complication after surgery and anesthesia, especially in elderly patients. Avenanthramide-C (AVC) test is a vascular endothelial cell adhesion molecule inhibitor with strong anti-inflammatory and antioxidant effects. The aim of this study was to investigate the effect and mechanism of AVC on POCD in aged rats to clarify the effect of AVC on POCD in aged rats. The aging rat model was established by continuous 200 mg/kg propofol anesthesia. Repeated propofol anesthesia could severely impair spatial learning ability, memory and cognitive function, and could promote hippocampal apoptosis, oxidative stress injury, neuroinflammation and ferroptosis in aging rats. In addition, AVC not only improved cognitive dysfunction, but also significantly inhibited apoptosis, neuroinflammatory response, ferroptosis and oxidative stress level in the hippocampus of aging rats induced by repeated anesthesia. Further mechanistic studies manifested that the above protective effects of AVC on aging rats induced by repeated propofol anesthesia may be achieved by activating Nrf2/ARE pathway activity. AVC pretreatment has a preventive effect on cognitive dysfunction induced by repeated propofol anesthesia in aging rats, and the preventive effect of AVC may be realized by activating the Nrf2/ARE signaling pathway activity. Our results demonstrate that AVC preconditioning reduces postoperative neuronal loss and neuroinflammation, activates the Nrf2/ARE pathway, reduces oxidative stress injury, and improves POCD in aged rats.

Correction: Systematic synthesis of bisected N-glycans and unique recognitions by glycan-binding proteins.

[This corrects the article DOI: 10.1039/D1SC05435J.].

Counterclockwise modular laparoscopic anatomical mesohepatectomy using combined glissonean pedicle (Takasaki approach) and hepatic vein-guided approaches.

Background: Although laparoscopic anatomical hepatectomy (LAH) is widely adopted today, laparoscopic anatomic mesohepatectomy (LAMH) for patients with hepatocellular carcinoma (HCC) remains technically challenging. Methods: In this study, 6 patients suffering from solitary liver tumors located in the middle lobe of the liver underwent counterclockwise modular LAMH using combined Glissonean pedicle (Takasaki approach) and hepatic vein-guided approaches. In this process, the Glissonean pedicle approach (Takasaki approach) was first used to transect the liver pedicles of segment right anterior (G58) and segment 4 (G4). Second, the hepatic vein-guided approach was performed along the umbilical fissure vein (UFV) to sever the liver parenchyma from the caudal to cranial direction, and the middle hepatic vein (MHV) and anterior fissure vein (AFV) were then disconnected at the root. Last, the hepatic vein-guided approach was once more performed along the ventral side of the right hepatic vein (RHV) to transect the liver parenchyma from the cranial to anterior direction, and the middle lobe of the liver, including the tumor, was removed completely. The entire process was applied in a counterclockwise fashion, and the exposure or transection sequence was G58, and G4, followed by UFV, MHV, AFV, and finally, the liver parenchyma along the ventral side of RHV. Results: The counterclockwise modular LAMH using combined Glissonean pedicle (Takasaki approach) and hepatic vein-guided approaches was feasible in all 6 cases. The median duration of the operation was 275 ± 35.07 min, and the mean estimated blood loss was 283.33 ml. All of the 6 patients recovered smoothly. The Clavien-Dindo Grade I-II complications rate was up to 33.33%, mainly characterized by postoperative pain and a small amount of ascites. No Clavien-Dindo Grade III-V complications occurred, and the mean postoperative hospital stay was 6.83 ± 1.47 days. Follow-up results showed that the average disease-free survival (DFS) was 12.17 months, and the 21-months OS rate, DFS rate and tumor recurrent rate were 100%, 83.33% and 16.67% respectively. Conclusions: Counterclockwise modular LAMH using combined Glissonean pedicle (Takasaki approach) and hepatic vein-guided approaches takes the advantages of the two approaches, is a novel protocol for LAMH. It is thought to be technically feasible for patients with a centrally located solitary HCC. The oncologic feasibility of this technique needs to be investigated based on long-term follow-up. A multicenter, large-scale, more careful study is necessary.

Design, synthesis and neurite outgrowth activity of novel ganglioside GM1 derivatives by remodeling of the fatty acid moiety.

Ganglioside GM1 is a glycosphingolipid found on mammalian cell membranes, and it is involved in ischemic encephalopathy, spinal cord injury and neurodegenerative diseases. Fatty acids, as a structure module of GM1, have been reported to affect its physiological function and neurite growth activity. Due to the limitation of preparation methods, the function of GM1 derivatives containing different fatty acids in nerve cells has not been systematically studied. To discover novel GM1 derivatives as nerve growth-promoting agents, we developed an efficient SA_SCDase enzymatic synthetic system of GM1 derivatives, yielding twenty GM1 derivatives with unsaturated fatty acid chains in high total yields (16-67%). Subsequently, the neurite outgrowth activities of GM1 derivatives were assessed on Neuro2a Cells. Among all the GM1 derivatives, GM1 (d18:1/C16:1) induced demonstrably neurite outgrowth activity. The subsequent RNA-sequencing (RNA-seq) and Western blot analysis was then performed and indicated that the mechanism of nerve cells growth involved cholesterol biosynthesis regulation by up-regulating SREBP2 expression or ERBB4 phosphorylation to activate the PI3K-mTOR pathway.

Systematic synthesis of bisected N-glycans and unique recognitions by glycan-binding proteins.

Bisected N-glycans represent a unique class of protein N-glycans that play critical roles in many biological processes. Herein, we describe the systematic synthesis of these structures. A bisected N-glycan hexasaccharide was chemically assembled with two orthogonal protecting groups attached at the C2 of the branching mannose residues, followed by sequential installation of GlcNAc and LacNAc building blocks to afford two asymmetric bisecting "cores". Subsequent enzymatic modular extension of the "cores" yielded a comprehensive library of biantennary N-glycans containing the bisecting GlcNAc and presenting 6 common glycan determinants in a combinatorial fashion. These bisected N-glycans and their non-bisected counterparts were used to construct a distinctive glycan microarray to study their recognition by a wide variety of glycan-binding proteins (GBPs), including plant lectins, animal lectins, and influenza A virus hemagglutinins. Significantly, the bisecting GlcNAc could bestow (PHA-L, rDCIR2), enhance (PHA-E), or abolish (ConA, GNL, anti-CD15s antibody, etc.) N-glycan recognition of specific GBPs, and is tolerated by many others. In summary, synthesized compounds and the unique glycan microarray provide ideal standards and tools for glycoanalysis and functional glycomic studies. The microarray data provide new information regarding the fine details of N-glycan recognition by GBPs, and in turn improve their applications.

Campylobacter jejuni permeabilizes the host cell membrane by short chain lysophosphatidylethanolamines.

Lysophospholipids (LPLs) are crucial for regulating epithelial integrity and homeostasis in eukaryotes, however the effects of LPLs produced by bacteria on host cells is largely unknown. The membrane of the human bacterial pathogen Campylobacter jejuni is rich in LPLs. Although C. jejuni possesses several virulence factors, it lacks traditional virulence factors like type III secretion systems, present in most enteropathogens. Here, we provide evidence that membrane lipids lysophosphatidylethanolamines (lysoPEs) of C. jejuni are able to lyse erythrocytes and are toxic for HeLa and Caco-2 cells. Lactate dehydrogenase (LDH) release assays and confocal microscopy revealed that lysoPE permeabilizes the cells. LysoPE toxicity was partially rescued by oxidative stress inhibitors, indicating that intracellular reactive oxygen species may contribute to the cell damage. Our results show that especially the short-chain lysoPEs (C:14) which is abundantly present in the C. jejuni membrane may be considered as a novel virulence factor.