Development of a new model for predicting recurrence after liver transplantation for hepatocellular carcinoma beyond Milan criteria / 临床肝胆病杂志

Objective To develop a new model for predicting recurrence after liver transplantation for hepatocellular carcinoma (HCC) beyond Milan criteria based on related preoperative and postoperative indicators. Methods A retrospective analysis was performed for the clinical data of the patients with HCC beyond Milan criteria who underwent orthotopic liver transplantation for the first time in Tianjin First Central Hospital from August 2014 to July 2018, and according to the presence or absence of recurrence during follow-up, the patients were divided into recurrence group and no-recurrence group. The t -test or the Mann-Whitney U test was used for comparison of continuous data between groups, and the chi-square test or the Fisher's exact test was used for comparison of categorical data between groups. The Kaplan-Meier method was used to plot survival curves, and the log-rank test was used for comparison of survival curves. Univariate and multivariate Cox proportional hazards regression analyses were used to identify the risk factors for recurrence-free survival after surgery. A new model was developed for recurrence after liver transplantation in the patients with HCC beyond Milan criteria based on the risk factors identified. The area under the receiver operating characteristic curve (AUC) was used to evaluate predictive performance, and the Hosmer-Lemeshow test was used to assess the goodness of fit of the model. Results A total of 117 patients with HCC beyond Milan criteria were enrolled in this study, with a median follow-up time of 24 (1-74) months. A total of 53 patients (45.3%) experienced recurrence after surgery, among whom 52 (98.1%) had recurrence within 3 years after surgery, with a median time to recurrence of 6 (1-52) months. The Cox proportional hazards regression analysis showed that preoperative serum alpha-fetoprotein (AFP) >769 ng/mL, neutrophil-lymphocyte ratio (NLR) >3.75, and ki67 index >0.25 were independent risk factors for recurrence-free survival after liver transplantation. The model established based on these three risk factors had an AUC of 0.843, with good sensitivity (88.7%) and specificity (70.3%). The optimal cut-off value was selected according to the maximization of Youden index, and then the patients were divided into low-risk group (0-1 point) and high-risk group (1.5-4 points). The log-rank test showed that the low-risk group had significantly higher 3-and 5-year recurrence-free survival rates than the high-risk group (84.1%/72.0% vs 10.9%/10.9%, χ 2 =29.425, P < 0.001). Conclusion Liver transplantation for HCC beyond Milan criteria should be performed with caution, and the predictive model established based on preoperative AFP, NLR, and ki67 index can accurately assess the indication for liver transplantation in such patients.

Aging weakens Th17 cell pathogenicity and ameliorates experimental autoimmune uveitis in mice

Aging-induced changes in the immune system are associated with a higher incidence of infection and vaccination failure. Lymph nodes, which filter the lymph to identify and fight infections, play a central role in this process. However, careful characterization of the impact of aging on lymph nodes and associated autoimmune diseases is lacking. We combined single-cell RNA sequencing (scRNA-seq) with flow cytometry to delineate the immune cell atlas of cervical draining lymph nodes (CDLNs) of both young and old mice with or without experimental autoimmune uveitis (EAU). We found extensive and complicated changes in the cellular constituents of CDLNs during aging. When confronted with autoimmune challenges, old mice developed milder EAU compared to young mice. Within this EAU process, we highlighted that the pathogenicity of T helper 17 cells (Th17) was dampened, as shown by reduced GM-CSF secretion in old mice. The mitigated secretion of GM-CSF contributed to alleviation of IL-23 secretion by antigen-presenting cells (APCs) and may, in turn, weaken APCs' effects on facilitating the pathogenicity of Th17 cells. Meanwhile, our study further unveiled that aging downregulated GM-CSF secretion through reducing both the transcript and protein levels of IL-23R in Th17 cells from CDLNs. Overall, aging altered immune cell responses, especially through toning down Th17 cells, counteracting EAU challenge in old mice.

Exploration and practice of patient satisfaction evaluation management in multi-campus public hospitals / 中华医院管理杂志

Patient satisfaction is one of the core indicators to measure the service quality of medical institutions. To this end, a multi-campus public hospital in Shanghai constructed a management system of patient satisfaction evaluation. Since 2021, its call center has conducted a full coverage satisfaction assessment for discharged patients from its three campuses and collected dissatisfaction information feedback. The hospital organized relevant clinical departments and functional departments to fully communicate with the dissatisfied patients according to the feedback information, followed by a joint rectification. The hospital regularly conducts in-depth analysis of all complaints for timely discovery of common problems in different campuses for continuous improvement. This practice can provide reference for multi-campus hospitals to promote homogeneous management, to improve management efficiency, service quality and patient satisfaction.

Method Establishment of Content Determination of Three Toxic Impurities in Glycerophosphorylcholine Raw Materials / 中国药房

OBJECTIVE： To establish GC-MS method for the content determination of three toxic impurities in glycerophosphorylcholine raw materials ，such as epichlorohydrin ，glycidyl，3-chloro-1，2-propanediol. METHODS ：Four batches of glycerophosphorylcholine raw materials were used as test samples. The determination was performed on ZB-WAXplus TM column， and the injector temperature was 200 ℃；the sample injection adopted splitless injection mode ，using helium （He）as carrier gas ， in constant current mode ；the temperature program for the column was initially heating at 30 ℃ for 1 min，rising to 220 ℃ at a speed of 30 ℃/min then remaining 5 min. The ion source was electrospray ion source （EI），the ion source temperature was 200 ℃，and the ionization energy was 70 eV；transmission interface temperature was 250 ℃，and mass spectrum monitoring mode was selected ion （SIM）. Detection ions were epichlorhydrin [mass charge ratio （m/z）49，57，62]，glycidyl（m/z 31，43，44）， 3-chloro-1，2-propanediol（m/z 44，61，79）. The solvent delay time was 3 min. RESULTS ：The linear range of epichlorhydrin ， glycidyl and 3-chloro-1，2-propanediol were 29.86-746.48，172.91-922.18，21.18-211.85 ng/mL，respectively（all r＞0.999 0）. The detection limits were 19.91，115.27，10.59 ng/mL，respectively. The limits of quantitation were 29.86，172.91，21.18 ng/mL， respectively. RSDs of precision （n＝6），reproducibility （n＝6） and stability （placed at room temperature for 12 h，n＝8） tests were all lower than 10％. The average recoveries were 93.88％，91.45％，91.86％，and RSDs were 5.10％，3.10％，2.49％ （n＝9），respectively. In the 4 batches of glycerophosphorylcholine raw materials ，three toxic impurities were all not detected. CONCLUSIONS：Established GC-MS method is simple ，efficient，accurate and repeatable ，and it can be used to determine the contents of three toxic impurities in glycerophosphorylcholine raw materials ，such as epichlorohydrin ，glycidyl，3-chloro-1， 2-propanediol.

Single-nucleus transcriptomic landscape of primate hippocampal aging

The hippocampus plays a crucial role in learning and memory, and its progressive deterioration with age is functionally linked to a variety of human neurodegenerative diseases. Yet a systematic profiling of the aging effects on various hippocampal cell types in primates is still missing. Here, we reported a variety of new aging-associated phenotypic changes of the primate hippocampus. These include, in particular, increased DNA damage and heterochromatin erosion with time, alongside loss of proteostasis and elevated inflammation. To understand their cellular and molecular causes, we established the first single-nucleus transcriptomic atlas of primate hippocampal aging. Among the 12 identified cell types, neural transiently amplifying progenitor cell (TAPC) and microglia were most affected by aging. In-depth dissection of gene-expression dynamics revealed impaired TAPC division and compromised neuronal function along the neurogenesis trajectory; additionally elevated pro-inflammatory responses in the aged microglia and oligodendrocyte, as well as dysregulated coagulation pathways in the aged endothelial cells may contribute to a hostile microenvironment for neurogenesis. This rich resource for understanding primate hippocampal aging may provide potential diagnostic biomarkers and therapeutic interventions against age-related neurodegenerative diseases.

Current status and prospects of molecular targeted therapy for liver cancer / 国际生物医学工程杂志

Liver cancer is a common liver malignant tumor and a common cause of death related to malignant tumors, which seriously threatens the lives of patients. In recent years, with the in-depth study of the occurrence and development of liver cancer, a clearer understanding of the occurrence and related molecular pathways of liver cancer has been developed, and a variety of molecular targeted drugs have been developed, mainly including anti-angiogenic drugs and immune checkpoints inhibitors. First-line anti-angiogenic drugs include sorafenib and lenvatinib, both of which can effectively prolong the survival of patients with unresectable advanced liver cancer. For patients with intolerable first-line drug adverse reactions or tumor progression during treatment, second-line drugs such as regorafenib and cabozantinib can also be selected, which may help prolong the survival of patients. Immune checkpoint inhibitors mainly include programmed cell death protein 1 and its ligand inhibitors and cytotoxic T lymphocyte-related antigen 4 inhibitors, both of which can inhibit immune checkpoints through a certain mechanism to prevent immune escape of tumor cells, and can effectively prolong the median survival time of patients with unresectable liver cancer. These two inhibitors are gradually being used in the clinical treatment of liver cancer.

SIRT7 antagonizes human stem cell aging as a heterochromatin stabilizer

SIRT7, a sirtuin family member implicated in aging and disease, is a regulator of metabolism and stress responses. It remains elusive how human somatic stem cell populations might be impacted by SIRT7. Here, we found that SIRT7 expression declines during human mesenchymal stem cell (hMSC) aging and that SIRT7 deficiency accelerates senescence. Mechanistically, SIRT7 forms a complex with nuclear lamina proteins and heterochromatin proteins, thus maintaining the repressive state of heterochromatin at nuclear periphery. Accordingly, deficiency of SIRT7 results in loss of heterochromatin, de-repression of the LINE1 retrotransposon (LINE1), and activation of innate immune signaling via the cGAS-STING pathway. These aging-associated cellular defects were reversed by overexpression of heterochromatin proteins or treatment with a LINE1 targeted reverse-transcriptase inhibitor. Together, these findings highlight how SIRT7 safeguards chromatin architecture to control innate immune regulation and ensure geroprotection during stem cell aging.

A human circulating immune cell landscape in aging and COVID-19

Age-associated changes in immune cells have been linked to an increased risk for infection. However, a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking. Here, we combined scRNA-seq, mass cytometry and scATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19. We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector, cytotoxic, exhausted and regulatory cells, along with increased late natural killer cells, age-associated B cells, inflammatory monocytes and age-associated dendritic cells. In addition, the expression of genes, which were implicated in coronavirus susceptibility, was upregulated in a cell subtype-specific manner with age. Notably, COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senescence. Therefore, these findings suggest that a dysregulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly.

SIRT7 antagonizes human stem cell aging as a heterochromatin stabilizer

SIRT7, a sirtuin family member implicated in aging and disease, is a regulator of metabolism and stress responses. It remains elusive how human somatic stem cell populations might be impacted by SIRT7. Here, we found that SIRT7 expression declines during human mesenchymal stem cell (hMSC) aging and that SIRT7 deficiency accelerates senescence. Mechanistically, SIRT7 forms a complex with nuclear lamina proteins and heterochromatin proteins, thus maintaining the repressive state of heterochromatin at nuclear periphery. Accordingly, deficiency of SIRT7 results in loss of heterochromatin, de-repression of the LINE1 retrotransposon (LINE1), and activation of innate immune signaling via the cGAS-STING pathway. These aging-associated cellular defects were reversed by overexpression of heterochromatin proteins or treatment with a LINE1 targeted reverse-transcriptase inhibitor. Together, these findings highlight how SIRT7 safeguards chromatin architecture to control innate immune regulation and ensure geroprotection during stem cell aging.

A human circulating immune cell landscape in aging and COVID-19

Age-associated changes in immune cells have been linked to an increased risk for infection. However, a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking. Here, we combined scRNA-seq, mass cytometry and scATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19. We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector, cytotoxic, exhausted and regulatory cells, along with increased late natural killer cells, age-associated B cells, inflammatory monocytes and age-associated dendritic cells. In addition, the expression of genes, which were implicated in coronavirus susceptibility, was upregulated in a cell subtype-specific manner with age. Notably, COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senescence. Therefore, these findings suggest that a dysregulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly.

Generation of a Hutchinson-Gilford progeria syndrome monkey model by base editing

Many human genetic diseases, including Hutchinson-Gilford progeria syndrome (HGPS), are caused by single point mutations. HGPS is a rare disorder that causes premature aging and is usually caused by a de novo point mutation in the LMNA gene. Base editors (BEs) composed of a cytidine deaminase fused to CRISPR/Cas9 nickase are highly efficient at inducing C to T base conversions in a programmable manner and can be used to generate animal disease models with single amino-acid substitutions. Here, we generated the first HGPS monkey model by delivering a BE mRNA and guide RNA (gRNA) targeting the LMNA gene via microinjection into monkey zygotes. Five out of six newborn monkeys carried the mutation specifically at the target site. HGPS monkeys expressed the toxic form of lamin A, progerin, and recapitulated the typical HGPS phenotypes including growth retardation, bone alterations, and vascular abnormalities. Thus, this monkey model genetically and clinically mimics HGPS in humans, demonstrating that the BE system can efficiently and accurately generate patient-specific disease models in non-human primates.

A human circulating immune cell landscape in aging and COVID-19

Age-associated changes in immune cells have been linked to an increased risk for infection. However, a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking. Here, we combined scRNA-seq, mass cytometry and scATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19. We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector, cytotoxic, exhausted and regulatory cells, along with increased late natural killer cells, age-associated B cells, inflammatory monocytes and age-associated dendritic cells. In addition, the expression of genes, which were implicated in coronavirus susceptibility, was upregulated in a cell subtype-specific manner with age. Notably, COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senescence. Therefore, these findings suggest that a dysregulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly.

Expressions of SENP1, SENP2 and SENP6 proteins in human glioma tissue and cells and their mechanisms / 吉林大学学报(医学版)

Objective:To observe the expressions of SENP1, SENP2and SENP6proteins in human malignant glioma tissue and cells, and to elucidate the their effects in the development of malignant glioma.Methods:The samples of normal human brain tissue and malignant glioma tissue were obtained and used as normal control group and malignant glioma group, respectively.The Cos7cells and the malignant glioma LN443and U343cells were cultured;the Cos7cells were used as normal cell control group, and the LN443and U343cells as malignant glioma cell group.Western blotting method was used to detect the expression levels of SENP1, SENP2and SENP6proteins in human malignant glioma tissue and cells.Results:In brain tissue, the expression levels of SENP1, SENP2and SENP6proteins in malignant glioma group were higher than those in normal control group (P＜0.05) .Compared with normal cell control group, the expression levels of SENP1, SENP2and SENP6proteins in the LN443and U343cells in malignant glioma cell group were significantly increased (P＜0.05) .Conclusion:SENP1, SENP2and SENP6proteins highly express in the malignant glioma tissue and cells, and they may play an important role in promoting the occurrence of malignant glioma.

Chemical screen identifies a geroprotective role of quercetin in premature aging

Aging increases the risk of various diseases. The main goal of aging research is to find therapies that attenuate aging and alleviate aging-related diseases. In this study, we screened a natural product library for geroprotective compounds using Werner syndrome (WS) human mesenchymal stem cells (hMSCs), a premature aging model that we recently established. Ten candidate compounds were identified and quercetin was investigated in detail due to its leading effects. Mechanistic studies revealed that quercetin alleviated senescence via the enhancement of cell proliferation and restoration of heterochromatin architecture in WS hMSCs. RNA-sequencing analysis revealed the transcriptional commonalities and differences in the geroprotective effects by quercetin and Vitamin C. Besides WS hMSCs, quercetin also attenuated cellular senescence in Hutchinson-Gilford progeria syndrome (HGPS) and physiological-aging hMSCs. Taken together, our study identifies quercetin as a geroprotective agent against accelerated and natural aging in hMSCs, providing a potential therapeutic intervention for treating age-associated disorders.

Modeling CADASIL vascular pathologies with patient-derived induced pluripotent stem cells

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary cerebrovascular disease caused by a NOTCH3 mutation. However, the underlying cellular and molecular mechanisms remain unidentified. Here, we generated non-integrative induced pluripotent stem cells (iPSCs) from fibroblasts of a CADASIL patient harboring a heterozygous NOTCH3 mutation (c.3226C>T, p.R1076C). Vascular smooth muscle cells (VSMCs) differentiated from CADASIL-specific iPSCs showed gene expression changes associated with disease phenotypes, including activation of the NOTCH and NF-κB signaling pathway, cytoskeleton disorganization, and excessive cell proliferation. In comparison, these abnormalities were not observed in vascular endothelial cells (VECs) derived from the patient's iPSCs. Importantly, the abnormal upregulation of NF-κB target genes in CADASIL VSMCs was diminished by a NOTCH pathway inhibitor, providing a potential therapeutic strategy for CADASIL. Overall, using this iPSC-based disease model, our study identified clues for studying the pathogenic mechanisms of CADASIL and developing treatment strategies for this disease.

Telomere-dependent and telomere-independent roles of RAP1 in regulating human stem cell homeostasis

RAP1 is a well-known telomere-binding protein, but its functions in human stem cells have remained unclear. Here we generated RAP1-deficient human embryonic stem cells (hESCs) by using CRISPR/Cas9 technique and obtained RAP1-deficient human mesenchymal stem cells (hMSCs) and neural stem cells (hNSCs) via directed differentiation. In both hMSCs and hNSCs, RAP1 not only negatively regulated telomere length but also acted as a transcriptional regulator of RELN by tuning the methylation status of its gene promoter. RAP1 deficiency enhanced self-renewal and delayed senescence in hMSCs, but not in hNSCs, suggesting complicated lineage-specific effects of RAP1 in adult stem cells. Altogether, these results demonstrate for the first time that RAP1 plays both telomeric and nontelomeric roles in regulating human stem cell homeostasis.

Differential stem cell aging kinetics in Hutchinson-Gilford progeria syndrome and Werner syndrome

Hutchinson-Gilford progeria syndrome (HGPS) and Werner syndrome (WS) are two of the best characterized human progeroid syndromes. HGPS is caused by a point mutation in lamin A (LMNA) gene, resulting in the production of a truncated protein product-progerin. WS is caused by mutations in WRN gene, encoding a loss-of-function RecQ DNA helicase. Here, by gene editing we created isogenic human embryonic stem cells (ESCs) with heterozygous (G608G/+) or homozygous (G608G/G608G) LMNA mutation and biallelic WRN knockout, for modeling HGPS and WS pathogenesis, respectively. While ESCs and endothelial cells (ECs) did not present any features of premature senescence, HGPS- and WS-mesenchymal stem cells (MSCs) showed aging-associated phenotypes with different kinetics. WS-MSCs had early-onset mild premature aging phenotypes while HGPS-MSCs exhibited late-onset acute premature aging characterisitcs. Taken together, our study compares and contrasts the distinct pathologies underpinning the two premature aging disorders, and provides reliable stem-cell based models to identify new therapeutic strategies for pathological and physiological aging.

CRISPR/Cas9-mediated gene knockout reveals a guardian role of NF-κB/RelA in maintaining the homeostasis of human vascular cells

Vascular cell functionality is critical to blood vessel homeostasis. Constitutive NF-κB activation in vascular cells results in chronic vascular inflammation, leading to various cardiovascular diseases. However, how NF-κB regulates human blood vessel homeostasis remains largely elusive. Here, using CRISPR/Cas9-mediated gene editing, we generated RelA knockout human embryonic stem cells (hESCs) and differentiated them into various vascular cell derivatives to study how NF-κB modulates human vascular cells under basal and inflammatory conditions. Multi-dimensional phenotypic assessments and transcriptomic analyses revealed that RelA deficiency affected vascular cells via modulating inflammation, survival, vasculogenesis, cell differentiation and extracellular matrix organization in a cell type-specific manner under basal condition, and that RelA protected vascular cells against apoptosis and modulated vascular inflammatory response upon tumor necrosis factor α (TNFα) stimulation. Lastly, further evaluation of gene expression patterns in IκBα knockout vascular cells demonstrated that IκBα acted largely independent of RelA signaling. Taken together, our data reveal a protective role of NF-κB/RelA in modulating human blood vessel homeostasis and map the human vascular transcriptomic landscapes for the discovery of novel therapeutic targets.

Vitamin C alleviates aging defects in a stem cell model for Werner syndrome

Werner syndrome (WS) is a premature aging disorder that mainly affects tissues derived from mesoderm. We have recently developed a novel human WS model using WRN-deficient human mesenchymal stem cells (MSCs). This model recapitulates many phenotypic features of WS. Based on a screen of a number of chemicals, here we found that Vitamin C exerts most efficient rescue for many features in premature aging as shown in WRN-deficient MSCs, including cell growth arrest, increased reactive oxygen species levels, telomere attrition, excessive secretion of inflammatory factors, as well as disorganization of nuclear lamina and heterochromatin. Moreover, Vitamin C restores in vivo viability of MSCs in a mouse model. RNA sequencing analysis indicates that Vitamin C alters the expression of a series of genes involved in chromatin condensation, cell cycle regulation, DNA replication, and DNA damage repair pathways in WRN-deficient MSCs. Our results identify Vitamin C as a rejuvenating factor for WS MSCs, which holds the potential of being applied as a novel type of treatment of WS.

Modeling xeroderma pigmentosum associated neurological pathologies with patients-derived iPSCs

Xeroderma pigmentosum (XP) is a group of genetic disorders caused by mutations of XP-associated genes, resulting in impairment of DNA repair. XP patients frequently exhibit neurological degeneration, but the underlying mechanism is unknown, in part due to lack of proper disease models. Here, we generated patient-specific induced pluripotent stem cells (iPSCs) harboring mutations in five different XP genes including XPA, XPB, XPC, XPG, and XPV. These iPSCs were further differentiated to neural cells, and their susceptibility to DNA damage stress was investigated. Mutation of XPA in either neural stem cells (NSCs) or neurons resulted in severe DNA damage repair defects, and these neural cells with mutant XPA were hyper-sensitive to DNA damage-induced apoptosis. Thus, XP-mutant neural cells represent valuable tools to clarify the molecular mechanisms of neurological abnormalities in the XP patients.