iPLA2ß loss leads to age-related cognitive decline and neuroinflammation by disrupting neuronal mitophagy.

BACKGROUND: During brain aging, disturbances in neuronal phospholipid metabolism result in impaired cognitive function and dysregulation of neurological processes. Mutations in iPLA2ß are associated with neurodegenerative conditions that significantly impact brain phospholipids. iPLA2ß deficiency exacerbates mitochondrial dysfunction and abnormal mitochondrial accumulation. We hypothesized that iPLA2ß contributes to age-related cognitive decline by disrupting neuronal mitophagy. METHODOLOGY: We used aged wild-type (WT) mice and iPLA2ß-/- mice as natural aging models to assess cognitive performance, iPLA2ß expression in the cortex, levels of chemokines and inflammatory cytokines, and mitochondrial dysfunction, with a specific focus on mitophagy and the mitochondrial phospholipid profile. To further elucidate the role of iPLA2ß, we employed adeno-associated virus (AAV)-mediated iPLA2ß overexpression in aged mice and re-evaluated these parameters. RESULTS: Our findings revealed a significant reduction in iPLA2ß levels in the prefrontal cortex of aged brains. Notably, iPLA2ß-deficient mice exhibited impaired learning and memory. Loss of iPLA2ß in the PFC of aged mice led to increased levels of chemokines and inflammatory cytokines. This damage was associated with altered mitochondrial morphology, reduced ATP levels due to dysregulation of the parkin-independent mitophagy pathway, and changes in the mitochondrial phospholipid profile. AAV-mediated overexpression of iPLA2ß alleviated age-related parkin-independent mitophagy pathway dysregulation in primary neurons and the PFC of aged mice, reduced inflammation, and improved cognitive function. CONCLUSIONS: Our study suggests that age-related iPLA2ß loss in the PFC leads to cognitive decline through the disruption of mitophagy. These findings highlight the potential of targeting iPLA2ß to ameliorate age-related neurocognitive disorders.

Diagnostic Value of Ultrasound Endoscopy-Guided Fine-Needle Aspiration for Peritoneal Lesions.

Background: Peritoneal lesions present diagnostic challenges, necessitating precise imaging techniques. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) offers a promising approach for accurate diagnosis, aiding in optimal patient management and treatment planning. Objective: This study aims to assess the diagnostic efficacy of EUS-FNA in peritoneal lesions to offer insight in guiding optimal patient management. Methods: A prospective observational study was conducted, and a total of 58 patients who underwent EUS-FNA of the peritoneum at our hospital between October 2021 and November 2021 were included. The ultrasound diagnostic instrument facilitated puncture guidance, with 2-5 punctures performed in various parts of the selected peritoneal lesion areas. The analysis encompassed evaluating the sensitivity, specificity, positive predictive value, and negative predictive value of biopsy for diagnosing peritoneal-associated lesions, alongside assessing the number of punctures, puncture satisfaction, and incidence of postoperative complications. Results: The included patients undergoing EUS-FNA revealed that 41 (70.69%) had malignant lesions, while 17 (29.31%) presented with benign lesions. The diagnostic accuracy of EUS-FNA for peritoneal lesions was determined to be 94.83%, with a diagnostic sensitivity of 97.30% for malignant tumors, specificity of 90.48%, positive predictive value of 94.74%, and negative predictive value of 95%. Lesions exhibited a size range of 2.5cm × 2.9cm to 15.2cm × 9.8cm. Each patient underwent 2-5 punctures (3.3 ± 1.4), with a puncture satisfaction rate of 96.55%. The incidence of postoperative complications following EUS-FNA was found to be 3.45%. Conclusion: EUS-FNA exhibits substantial diagnostic utility for peritoneal-related lesions, marked by exceptional accuracy, sensitivity, specificity, and favorable safety. Its clinical adoption is warranted, promising improved patient care and management.

ELF5 drives angiogenesis suppression though stabilizing WDTC1 in renal cell carcinoma.

BACKGROUND: Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system. Angiogenesis is a main contributing factor for tumorigenesis. E74-like transcription factor 5 (ELF5) has been verified to participate in the progression of different cancers and can regulate angiogenesis. This study was aimed to explore the functions of ELF5 in RCC. METHODS: Bioinformatics tools were used to predict the expression of ELF5 in RCC. RT-qPCR was applied for testing ELF5 expression in RCC cells. Cell behaviors were evaluated by colony formation, CCK-8, and transwell assays. The tube formation assay was used for determining angiogenesis. Methylation-specific PCR (MSP) was utilized for measuring the methylation level of ELF5 in RCC cells. ChIP and luciferase reporter assays were applied for assessing the binding of ELF5 and ubiquitin-specific protease 3 (USP3). Co-IP and GST pull-down were utilized for detecting the interaction of WD40 and tetratricopeptide repeats 1 (WDTC1) and USP3. Ubiquitination level of WDTC1 was determined by ubiquitination assay. RESULTS: ELF5 was lowly expressed in RCC cells and tissues. High expression of ELF5 expression notably suppressed RCC cell proliferative, migratory, and invasive capabilities, and inhibited angiogenesis. The tumor growth in mice was inhibited by ELF5 overexpression. ELF5 was highly methylated in RCC samples, and DNA methyltransferases (DNMTs) can promote hypermethylation level of ELF5 in RCC cells. ELF5 was further proved to transcriptionally activate USP3 in RCC. Moreover, USP3 inhibited WDTC1 ubiquitination. ELF5 can promote USP3-mediated WDTC1 stabilization. Additionally, WDTC1 silencing reversed the functions of ELF5 overexpression on RCC progression. CONCLUSION: Downregulation of ELF5 due to DNA hypermethylation inhibits RCC development though the USP3/WDTC1axis in RCC.

Involvement of circHIPK3 in the pathogenesis of diabetic cardiomyopathy in mice.

AIMS/HYPOTHESIS: In a mouse model of diabetic cardiomyopathy (DCM) the expression of the circular RNA circHIPK3 was found to be significantly increased. This study aimed to discover the molecular mechanisms linking circHIPK3 to the pathogenesis of DCM. METHODS: The diabetic mouse model was established by i.p. injection of streptozotocin, which led to the development of DCM. Echocardiographic measurements were used to evaluate cardiac structure and function, and histological staining was applied to detect myocardial fibrosis in mice. 5-Ethynyl-2'-deoxyuridine incorporation was performed to determine cell proliferation and RNA fluorescent in situ hybridisation was employed to examine circHIPK3 expression in cardiac fibroblasts. RNA immunoprecipitation and luciferase reporter assay were conducted to explore the pathological mechanism of circHIPK3 in myocardial fibrosis. RESULTS: Knockdown of circHIPK3 was found to attenuate myocardial fibrosis and enhance cardiac function in DCM mice. In addition, silencing of circHIPK3 could suppress proliferation of cardiac fibroblasts treated with angiotensin II. Furthermore, RNA immunoprecipitation and luciferase reporter assay revealed a circHIPK3-miR-29b-3p-Col1a1-Col3a1 regulatory network in the pathogenesis of myocardial fibrosis. CONCLUSIONS/INTERPRETATION: circHIPK3 contributes to increased myocardial fibrosis during DCM by functioning as a competing endogenous RNA that upregulates Col1a1 and Col3a1 expression through suppressing miR-29b-3p.

Cellular analysis of a novel mutation p. Ser287Tyr in TOR1A in late-onset isolated dystonia.

BACKGROUND: Variations in TOR1A were thought to be associated with early-onset isolated dystonia. The variant S287Y (NM_000113.2: c.860C > A, p. Ser287Tyr, rs766483672) was found in our late-onset isolated dystonia patient. This missense variant is adjacent to R288Q (c.863G > A, p. Arg288Gln), which was reported to be associated with isolated dystonia. The potentially pathogenic role of S287Y is not conclusively known. METHODS: Cytological and molecular biological analyses were performed in vitro to determine whether this variant damages the structure and function of the cell. RESULTS: Compared with the SH-SY5Y cells overexpressing wild-type TOR1A, the cells overexpressing the protein with S287Y have an enlarged peri-nuclear space. The same changes in nuclear morphology were also found in the cells overexpressing the pathogenic variants ΔE (NM_000113.2:c.904_906delGAG, p. Glu302del), F205I (NM_000113.2:c.613 T > A, p. Phe205Ile), and R288Q (NM_000113.2:c.863G > A, p. Arg288Gln). Mutated proteins with S287Y presented a higher tendency to form dimers under reducing conditions. The same tendencies were observed in other mutated proteins but not in wild-type torsinA. CONCLUSIONS: TorsinA with S287Y damages the structure of the cell nucleus and may be a novel pathogenic mutation that causes isolated dystonia.

Bioinformatic analysis reveals hub genes and pathways that promote melanoma metastasis.

BACKGROUND: Melanoma has the highest mortality rate of all skin tumors, and metastases are the major cause of death from it. The molecular mechanism leading to melanoma metastasis is currently unclear. METHODS: With the goal of revealing the underlying mechanism, three data sets with accession numbers GSE8401, GSE46517 and GSE7956 were downloaded from the Gene Expression Omnibus (GEO) database. After identifying the differentially expressed gene (DEG) of primary melanoma and metastatic melanoma, three kinds of analyses were performed, namely functional annotation, protein-protein interaction (PPI) network and module construction, and co-expression and drug-gene interaction prediction analysis. RESULTS: A total of 41 up-regulated genes and 79 down-regulated genes was selected for subsequent analyses. Results of pathway enrichment analysis showed that extracellular matrix organization and proteoglycans in cancer are closely related to melanoma metastasis. In addition, seven pivotal genes were identified from PPI network, including CXCL8, THBS1, COL3A1, TIMP3, KIT, DCN, and IGFBP5, which have all been verified in the TCGA database and clinical specimens, but only CXCL8, THBS1 and KIT had significant differences in expression. CONCLUSIONS: To conclude, CXCL8, THBS1 and KIT may be the hub genes in the metastasis of melanoma and thus may be regarded as therapeutic targets in the future.

Down-regulation of the insulin signaling pathway by SHC may correlate with congenital heart disease in Chinese populations.

BACKGROUND/AIMS: Congenital heart disease (CHD) is one of the most common and severe congenital defects. The incidence of fetal cardiac malformation is increased in the context of maternal gestational diabetes mellitus (GDM). Therefore, we wanted to determine whether abnormalities in the insulin signaling pathway are associated with the occurrence of nonsyndromic CHD (ns-CHD). METHODS: We used digital gene expression profiling (DGE) of right atrial myocardial tissue samples from eight ns-CHD patients and four controls. The genes potentially associated with CHD were validated by real-time fluorescence quantitative PCR analysis of right atrial myocardial tissues from 37 patients and 10 controls and the H9C2 cell line. RESULTS: The results showed that the insulin signaling pathway, which is mediated by the SHC gene family, was inhibited in the ns-CHD patients. The expression levels of five genes (PTPRF, SHC4, MAP2K2, MKNK2, and ELK1) in the pathway were significantly down-regulated in the patients' atrial tissues (P<0.05 for all). In vitro, the H9C2 cells cultured in high glucose (33 mmol/l) expressed less SHC4, MAP2K2, and Elk-1 than those cultured in low glucose (25 mmol/l). Furthermore, the high glucose concentration down-regulated the 25 genes associated with blood vessel development based on Gene Ontology (GO) term enrichment analyses of RNA-seq data. CONCLUSION: We considered that changes in the insulin signaling pathway mediated by SHC might be involved in the heart development process. This mechanism might account for the increase in the incidence of fetal cardiac malformations in the context of GDM.

Laparoscopic based renal denervation in a canine neurogenic hypertension model.

BACKGROUND: Previous renal denervation (RDN) studies showed controversial results in reducing blood pressure. The aim of this study was to provide evidence supporting the effectiveness of laparoscopic-based renal denervation (L-RDN) in treating hypertension. METHODS: Sixteen Beagle dogs were randomly divided into RDN group (n = 12) and sham group (n = 4). Neurogenic hypertension was generated in all dogs via carotid artery route. L-RDN was performed in the RDN group, with sham operation performed as a control. Blood pressure (BP) changes were recorded at 2, 4, 6, and 8 weeks after the procedure. Changes in serum creatinine (sCr), blood urea nitrogen (BUN) and level of norepinephrine (NE) were analyzed. Histological changes of kidney and renal arteries were also evaluated. RESULTS: BP and NE levels were significantly elevated after hypertension induction (p < 0.01). Systolic and diastolic BP of RDN group were decreased by 15.5 mmHg and 7.3 mmHg (p < 0.0001 and p = 0.0021, respectively) at the eighth week after L-RDN. Invasive systolic and diastolic BP of RDN group were significantly decreased by 14.5 mmHg and 15.3 mmHg (p < 0.0001). In contrast, there was no significant decrease in blood pressure in the sham group. In addition, RDN group but not the sham group showed a significant decrease in NE levels (p < 0.001), while no significant changes in sCr and BUN were observed in both groups. Pathological examinations showed no discernible damage, tear, or dissection to the renal arteries in RND group. CONCLUSIONS: L-RDN lowered BP and NE levels in hypertensive dogs without affecting renal artery morphology and kidney function.

Loureirin hydrogel promotes healing of radionuclide-contaminated wounds by regulating angiogenesis and immune cells.

Radionuclide-contaminated wounds face clinical dilemmas such as repeated erosion and ulceration and are difficult to heal. In this work, we aimed to develop a biodegradable hydrogel with a beneficial effect on radionuclide-contaminated wounds and initially investigated the mechanism of action of the hydrogel. The hydrogel was produced through the ring-opening polymerization of polycaprolactone (PCL) triggered by polyethylene glycol (PEG), and its physicochemical properties were characterized by gel permeation chromatography, nuclear magnetic resonance, rheological properties testing, and other techniques. The low critical solution temperatures were 30 °C and 46 °C, which are suitable for the human body to realize the degradable properties of the hydrogel. A radionuclide-contaminated wound model was established, which proved that the biodegradable hydrogel had good healing properties and did not form secondary lesions. The effect was better than clinically used EGF or VB12. Pathological results showed that mature granulation tissue formed on the 7th day after the injury, and by the 10th day after the injury, the scab had completely fallen off, the epithelial coverage had reached over 70% and the wound was essentially completely healed. Additionally, the hydrogel affects immune metabolism, regulates immune cell function, promotes the formation of new blood vessels and granular tissue, and effectively accelerates the healing process of radionuclide-contaminated wounds.

Temporal transcriptomic dynamics in developing macaque neocortex.

Despite intense research on mice, the transcriptional regulation of neocortical neurogenesis remains limited in humans and non-human primates. Cortical development in rhesus macaque is known to recapitulate multiple facets of cortical development in humans, including the complex composition of neural stem cells and the thicker supragranular layer. To characterize temporal shifts in transcriptomic programming responsible for differentiation from stem cells to neurons, we sampled parietal lobes of rhesus macaque at E40, E50, E70, E80, and E90, spanning the full period of prenatal neurogenesis. Single-cell RNA sequencing produced a transcriptomic atlas of developing parietal lobe in rhesus macaque neocortex. Identification of distinct cell types and neural stem cells emerging in different developmental stages revealed a terminally bifurcating trajectory from stem cells to neurons. Notably, deep-layer neurons appear in the early stages of neurogenesis, while upper-layer neurons appear later. While these different lineages show overlap in their differentiation program, cell fates are determined post-mitotically. Trajectories analysis from ventricular radial glia (vRGs) to outer radial glia (oRGs) revealed dynamic gene expression profiles and identified differential activation of BMP, FGF, and WNT signaling pathways between vRGs and oRGs. These results provide a comprehensive overview of the temporal patterns of gene expression leading to different fates of radial glial progenitors during neocortex layer formation.

ROS-sensitive Crocin-loaded chitosan microspheres for lung targeting and attenuation of radiation-induced lung injury.

Radiation-induced lung injury (RILI) is one of the major complications in patients exposed to accidental radiation and radiotherapy for thoracic malignancies. However, there is no reliable radioprotector for effective clinical treatment of RILI so far. Herein, a novel Crocin-loaded chitosan microsphere is developed for lung targeting and attenuation of RILI. The chitosan microspheres are modified with 4-carboxyphenylboronic acid and loaded with the natural antioxidant Crocin-I to give the drug-loaded microspheres (~10 µm). The microspheres possess good biocompatibility in vivo and in vitro. In a mouse model, they exhibit effective passive targeting performance and a long retention time in the lung after intravenous administration. Furthermore, they improve the radioprotective effect of Crocin-I for the treatment of RILI by reducing the level of inflammatory cytokines in bronchoalveolar lavage fluid and by regulating oxidative stress in lung tissues. The targeted agents significantly improved the bioavailability and radioprotection of Crocin-I by the outstanding passive targeting effect. This work may provide a promising strategy for efficient radioprotection on RILI using passive lung targeting microspheres.

EZH2 inhibitor DZNep blocks cell proliferation of GCB-DLBCL cells by upregulating p16.

Diffuse large B-cell lymphomas (DLBCLs) are phenotypically and genetically heterogeneous. Two main subgroups of DLBCL include germinal center B-cell-like (GCB) and activated B-cell-like (ABC). Molecular profiling can further classify DLBCL into four subtypes: MCD (both CD79B and MYD88 L265P), BN2 (NOTCH2 mutation or BCL6 fusion), N1 (NOTCH1 mutation), or EZB (EZH2 mutation or BCL2 fusion). EZH2 inhibitors were recommended for patients with the EZB subtype of DLBCLs; however, little is known about the therapeutic mechanisms. Our results showed that DZNep arrested G1/S phase of GCB-DLBCL cells and inhibited the cell proliferation in vitro through upregulation of p16 by demethylating its promoter. These results suggest that DZNep may have potential as a novel therapeutic agent for DFLBL therapy. This agent may serve as a novel molecular agent to be applied to GCB DLBCL.

Activation of STAT6 by intranasal allergens correlated with the development of eosinophilic chronic rhinosinusitis in a mouse model.

Eosinophilic chronic rhinosinusitis (ECRS) is a chronic inflammatory disease characterized by prominent eosinophilic infiltration along with a T-helper-2 (Th2) response. It has been well documented that signal transducer and activator of transcription 6 (STAT6) is a nuclear transcription factor that mediates Th2-type immunity and is implicatory of STAT1 and STAT3 in the pathogenesis of allergic airway diseases. However, little is known about the association between STATs and ECRS. Here, we explored the relationship between STAT1, STAT3, and/or STAT6 and eosinophilic inflammation accompanied by Th2-type immunity in a mouse model of ECRS. An ovalbumin (OVA)-staphylococcal enterotoxin B (SEB)-induced ECRS murine model was first established. The mucosal histological alterations were determined using hematoxylin and eosin staining. The number of eosinophils in peripheral blood was measured using a blood cell analyzer. The cytokine (IL-4, IL-5, IL17 A and IFN-γ) expression levels in the sinonasal mucosa and total and OVA-specific IgE from serum were measured using ELISA. Then, the protein levels of STAT1, STAT3, STAT6, phosphorylated STAT1 (p-STAT1), p-STAT3, p-STAT6, T-box expressed in T-cells (T-bet), GATA binding protein 3 (GATA-3), and retinoic acid receptor-related orphan receptor γ (RORγt) in the sinonasal mucosa were examined by immunohistochemical staining or Western blotting. Local administration of OVA combined with SEB (OVA + SEB) induced multiple polyp-like lesions, accompanied by prominent eosinophilic infiltration in the sinonasal mucosa. The OVA- and OVA+SEB-treated groups showed significantly higher eosinophil counts from peripheral blood and total and OVA-specific IgE levels from serum than those in the PBS- and SEB-treated groups. The levels of p-STAT6 were markedly increased by OVA + SEB exposure, as well as GATA-3, IL-4, and IL-5, but did not affect STAT6, p-STAT1, p-STAT3, T-bet, RORγt, IFN-γ, or IL-17A. Furthermore, an eosinophil count in the sinonasal mucosa showed a positive correlation with the level of p-STAT6 in the ECRS mouse model. Signal transducer and activator of transcription 6 signaling could be activated in the OVA+SEB-induced ECRS model and might be a crucial signal transducer in the development of Th2-skewed ECRS.

Diagnostic efficacy of different pathologic methods for assessing tissue obtained by endoscopic ultrasound-guided fine needle aspiration: a prospective study.

AIMS: The best method for processing specimens by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has not been standardized and varies considerably between medical centers. The purpose of this study is to explore whether a combination of histologic and cytologic methods can increase the diagnostic efficacy of EUS-FNA in solid lesions around the digestive tract. METHODS: We recruited 52 patients (65 cases total) with solid lesions around the digestive tract who underwent EUS-FNA as performed by the same endoscopic physician from December 2016 to January 2018. All the EUS-FNA specimens were processed by conventional smear cytology (CS), liquid-based cytology (LBC), cell block (CB), and histopathology. All the pathologic results were tracked to investigate the diagnostic value of the methods. RESULTS: Fifty-three malignant lesions and 12 benign lesions were analyzed. The diagnostic accuracy levels of the CS, LBC, CB, and histopathology were 96.9%, 89.2%, 91.9%, and 48.1%, respectively. CS had a higher diagnostic accuracy than CB (P < 0.05) and LBC (P < 0.05). The cytologic methods had a significantly higher diagnostic accuracy than histopathology (P < 0.05). The combined diagnostic accuracy of all the methods was 100%. The diagnostic sensitivities of the CS, LBC, CB and histopathology were 96.2%, 86.8%, 90.4%, and 37.2%, respectively, and the diagnostic specificity of each of the four methods was 100%. CONCLUSIONS: Different pathological methods can compensate for one another, substantially improving the overall positive detection rate of EUS-FNA. Combining cytology and histology can contribute additional diagnostic efficacy to EUS-FNA in solid lesions around the digestive tract.

A case of rectal metastasis of ovarian carcinoma diagnosed by endoscopic ultrasound-guided fine-needle aspiration: A case report and brief review of the literature (with videos).

When colorectal subepithelial lesions occur in ovarian carcinoma patients, EUS-FNA may help to diagnose colorectal metastasis, thereby guiding clinicians to select appropriate treatment and improve the overall outcome.

Development and Validation of an Autophagy-Related Signature for Head and Neck Squamous Cell Carcinoma.

INTRODUCTION: HNSCC is the sixth most frequent type of malignant carcinoma with a low prognosis rate. In addition, autophagy is important in cancer development and progression. The purpose of this study is to investigate the potential significance of ARGs in the diagnosis and treatment of HNSCC. MATERIALS AND METHODS: Expression data and clinical information of HNSCC samples were collected from the TCGA database, and a list of ARGs was obtained from the MSigDB. Then, we used R software to perform differential expression analysis and functional enrichment analysis. Further analysis was also performed to find out the survival-related ARGs in HNSCC, and two prognosis-related ARGs, FADD and NKX2-3, were selected to construct a prognosis prediction model. Moreover, some methods were applied to validate the prognosis prediction model. Finally, we used cell lines and clinical tissue samples of HNSCC to analyze the importance of FADD and NKX2-3. RESULTS: We screened a total of 38 differentially expressed ARGs, and enrichment analysis showed that these genes were mainly involved in autophagy. Then, we selected FADD and NKX2-3 to construct a prognosis model and the risk score calculated by the model was proved to be effective in predicting the survival of HNSCC patients. Additionally, significant differences of the clinicopathological parameters could also be observed in the risk scores and the expression of NKX2-3 and FADD. The expression of FADD and NKX2-3 in cell lines and HNSCC tissue samples also showed the same trends. CONCLUSIONS: ARGs may be a potential biomarker for HNSCC prognosis, and targeted therapies for FADD and NKX2-3 are possible to be a new strategy of HNSCC treatment.

Long Non-coding RNA T-uc.189 Modulates Neural Progenitor Cell Fate by Regulating Srsf3 During Mouse Cerebral Cortex Development.

Neurogenesis is a complex process that depends on the delicate regulation of spatial and temporal gene expression. In our previous study, we found that transcribed ultra-conserved regions (T-UCRs), a class of long non-coding RNAs that contain UCRs, are expressed in the developing nervous systems of mice, rhesus monkeys, and humans. In this study, we first detected the full-length sequence of T-uc.189, revealing that it was mainly concentrated in the ventricular zone (VZ) and that its expression decreased as the brain matured. Moreover, we demonstrated that knockdown of T-uc.189 inhibited neurogenesis. In addition, we found that T-uc.189 positively regulated the expression of serine-arginine-rich splicing factor 3 (Srsf3). Taken together, our results are the first to demonstrate that T-uc.189 regulates the expression of Srsf3 to maintain normal neurogenesis during cortical development.

The olfactory route is a potential way for SARS-CoV-2 to invade the central nervous system of rhesus monkeys.

Neurological manifestations are frequently reported in the COVID-19 patients. Neuromechanism of SARS-CoV-2 remains to be elucidated. In this study, we explored the mechanisms of SARS-CoV-2 neurotropism via our established non-human primate model of COVID-19. In rhesus monkey, SARS-CoV-2 invades the CNS primarily via the olfactory bulb. Thereafter, viruses rapidly spread to functional areas of the central nervous system, such as hippocampus, thalamus, and medulla oblongata. The infection of SARS-CoV-2 induces the inflammation possibly by targeting neurons, microglia, and astrocytes in the CNS. Consistently, SARS-CoV-2 infects neuro-derived SK-N-SH, glial-derived U251, and brain microvascular endothelial cells in vitro. To our knowledge, this is the first experimental evidence of SARS-CoV-2 neuroinvasion in the NHP model, which provides important insights into the CNS-related pathogenesis of SARS-CoV-2.

Case of an abnormal procalcitonin-producing metastatic pancreatic neuroendocrine tumor.

Procalcitonin (PCT) is widely used to diagnose a bacterial infection. An increased serum PCT can also be observed in tumors. We presented an unusual case of a metastatic PNET producing and secreting PCT. Immunohistochemistry was used to demonstrate that PCT can be secreted by PanNET.