Sex differences in fetal brain functional network topology.

The fetal period is a critical stage in brain development, and understanding the characteristics of the fetal brain is crucial. Although some studies have explored aspects of fetal brain functional networks, few have specifically focused on sex differences in brain network characteristics. We adopted the graph theory method to calculate brain network functional connectivity and topology properties (including global and nodal properties), and further compared the differences in these parameters between male and female fetuses. We found that male fetuses showed an increased clustering coefficient and local efficiency than female fetuses, but no significant group differences concerning other graph parameters and the functional connectivity matrix. Our study suggests the existence of sex-related distinctions in the topological properties of the brain network at the fetal stage of development and demonstrates an increase in brain network separation in male fetuses compared with female fetuses.

A multicenter study of cervical cancer using quantitative diffusion-weighted imaging.

BACKGROUND: Parameters from diffusion-weighted imaging (DWI) have been increasingly used as imaging biomarkers for the diagnosis and monitoring of treatment responses in cancer. The consistency of DWI measurements across different centers remains uncertain, which limits the widespread use of quantitative DWI in clinical settings. PURPOSE: To investigate the consistency of quantitative metrics derived from DWI between different scanners in a multicenter clinical setting. MATERIAL AND METHODS: A total of 193 patients with cervical cancer from four scanners (MRI1, MRI2, MRI3, and MRI4) at three centers were included in this retrospective study. DWI data were processed using the mono-exponential and intravoxel incoherent motion (IVIM) model, yielding the following parameters: apparent diffusion coefficient (ADC); true diffusion coefficient (D); pseudo-diffusion coefficient (D*); perfusion fraction (f); and the product of f and D* (fD*). Various parameters of cervical cancer obtained from different scanners were compared. RESULTS: The parameters D and ADC derived from MRI1 and MRI2 were significantly different from those derived from MRI3 or MRI4 (P <0.01 for all comparisons). However, there was no significant difference in cervical cancer perfusion parameters (D* and fD*) between the different scanners (P >0.05). The P values of comparisons of all DWI parameters (D, D*, fD*, and ADC) between MRI3 and MRI4 (same vendor in different centers) for cervical cancer were all >0.05, except for f (P = 0.05). CONCLUSION: Scanners of the same model by the same vendor can yield close measurements of the ADC and IVIM parameters. The perfusion parameters showed higher consistency among the different scanners.

The differential value of radiomics based on traditional T1-weighted sequences in newborns with hyperbilirubinemia.

BACKGROUND: On the basis of visual-dependent reading method, radiological recognition and assessment of neonatal hyperbilirubinemia (NH) or acute bilirubin encephalopathy (ABE) on conventional magnetic resonance imaging (MRI) sequences are challenging. Prior studies had shown that radiomics was possible to characterize ABE-induced intensity and morphological changes on MRI sequences, and it has emerged as a desirable and promising future in quantitative and objective MRI data extraction. To investigate the utility of radiomics based on T1-weighted sequences for identifying neonatal ABE in patients with hyperbilirubinemia and differentiating between those with NH and the normal controls. METHODS: A total of 88 patients with NH were enrolled, including 50 patients with ABE and 38 ABE-negative individuals, and 70 age-matched normal neonates were included as controls. All participants were divided into training and validation cohorts in a 7:3 ratio. Radiomics features extracted from the basal ganglia of T1-weighted sequences on magnetic resonance imaging were evaluated and selected to set up the prediction model using the K-nearest neighbour-based bagging algorithm. A receiver operating characteristic curve was plotted to assess the differentiating performance of the radiomics-based model. RESULTS: Four of 744 radiomics features were selected for the diagnostic model of ABE. The radiomics model yielded an area under the curve (AUC) of 0.81 and 0.82 in the training and test cohorts, with accuracy, precision, sensitivity, and specificity of 0.82, 0.80, 0.91, and 0.69 and 0.78, 0.8, 0.8, and 0.75, respectively. Six radiomics features were selected in this model to distinguish those with NH from the normal controls. The AUC for the training cohort was 0.97, with an accuracy of 0.92, a precision of 0.92, a sensitivity of 0.93, and a specificity of 0.90. The performance of the radiomics model was confirmed by testing the test cohort, and the AUC, accuracy, precision, sensitivity, and specificity were 0.97, 0.92, 0.96, 0.89, and 0.95, respectively. CONCLUSIONS: The proposed radiomics model based on traditional TI-weighted sequences may be used effectively for identifying ABE and even differentiating patients with NH from the normal controls, which can provide microcosmic information beyond experience-dependent vision and potentially assist in clinical diagnosis and treatment.

Three-dimensional ultrashort echo time magnetic resonance imaging in pediatric patients with pneumonia: a comparative study.

BACKGROUND: UTE has been used to depict lung parenchyma. However, the insufficient discussion of its performance in pediatric pneumonia compared with conventional sequences is a gap in the existing literature. The objective of this study was to compare the diagnostic value of 3D-UTE with that of 3D T1-GRE and T2-FSE sequences in young children diagnosed with pneumonia. METHODS: Seventy-seven eligible pediatric patients diagnosed with pneumonia at our hospital, ranging in age from one day to thirty-five months, were enrolled in this study from March 2021 to August 2021. All patients underwent imaging using a 3 T pediatric MR scanner, which included three sequences: 3D-UTE, 3D-T1 GRE, and T2-FSE. Subjective analyses were performed by two experienced pediatric radiologists based on a 5-point scale according to six pathological findings (patchy shadows/ground-glass opacity (GGO), consolidation, nodule, bulla/cyst, linear opacity, and pleural effusion/thickening). Additionally, they assessed image quality, including the presence of artifacts, and evaluated the lung parenchyma. Interrater agreement was assessed using intraclass correlation coefficients (ICCs). Differences among the three sequences were evaluated using the Wilcoxon signed-rank test. RESULTS: The visualization of pathologies in most parameters (patchy shadows/GGO, consolidation, nodule, and bulla/cyst) was superior with UTE compared to T2-FSE and T1 GRE. The visualization scores for linear opacity were similar between UTE and T2-FSE, and both were better than T1-GRE. In the case of pleural effusion/thickening, T2-FSE outperformed the other sequences. However, statistically significant differences between UTE and other sequences were only observed for patchy shadows/GGO and consolidation. The overall image quality was superior or at least comparable with UTE compared to T2-FSE and T1-GRE. Interobserver agreements for all visual assessments were significant and rated "substantial" or "excellent." CONCLUSIONS: In conclusion, UTE MRI is a useful and promising method for evaluating pediatric pneumonia, as it provided better or similar visualization of most imaging findings compared with T2-FSE and T1-GRE. We suggest that the UTE MRI is well-suited for pediatric population, especially in younger children with pneumonia who require longitudinal and repeated imaging for clinical care or research and are susceptible to ionizing radiation.

[Xiongcan Yishen Formula up-regulates the clock gene expressions in the testis tissue of the rats with late-onset hypogonadism].

OBJECTIVE: To investigate the effect of Xiongcan Yishen Formula (XYF) on the expressions of the clock genes in the testis tissue of the rats with late-onset hypogonadism (LOH). METHODS: Forty-eight 8-week-old male SD rats were randomly divided into 6 groups, normal control, model control, testosterone propionate (TP), and low-, medium- and high-dose XYF. The LOH model was made in the later 5 groups of rats by intraperitoneal injection of D-galactose at 480 mg/kg/d for 56 successive days, while the normal controls were injected with the same volume of normal saline. After modeling, the rats in the low-, medium- and high-dose XYF groups were treated intragastrically with XYF at 10.4, 20.8 and 41.6 g/kg/d, bid, respectively, those in the normal and model control groups with the same volume of distilled water, and those in the TP group intramuscularly with TP at 5.21 mg/kg/d, qd alt, all for 28 days. After treatment, the supernatant was obtained for measurement of the serum T level by ELISA, and the testis tissue collected for determination of the mRNA and protein expressions of BMAL1, NR1D1, PER2, CRY1, StAR and CYP11A1 by RT-qPCR and Western blot. RESULTS: Compared with the normal controls, the rats in the LOH model control group showed significantly decreased serum T and mRNA and protein expressions of BMAL1, NR1D1, PER2, CRY1, StAR and CYP11A1 (P < 0.05). In comparison with the findings in the model controls, the T level was remarkably increased in the TP and XYF groups (P < 0.05), the expressions of StAR mRNA and CYP11A1 mRNA and protein markedly up-regulated in the high-dose XYF group (P < 0.05), and so was the expression of the StAR protein in the XYF and TP groups (P < 0.05), those of BMAL1 and NR1D1 proteins and PER2 mRNA and protein in the high-dose XYF group (P < 0.05), those of BMAL1 mRNA and CRY1 protein in the medium- and high-dose XYF groups (P < 0.05), that of NR1D1 mRNA in the XYF and TP groups (P < 0.05), and that of CRY1 mRNA in the medium- and high-dose XYF and TP groups (P < 0.05). CONCLUSION: Xiongcan Yishen Formula could up-regulate the expressions of the clock genes in the testis tissue of the LOH rats and increase the serum T level as well, which may underlie the mechanisms of Xiongcan Yishen Formula acting on LOH.

Preliminary Study on Quantitative Assessment of the Fetal Brain Using MOLLI T1 Mapping Sequence.

BACKGROUND: Prenatal quantitative evaluation of myelin is important. However, few techniques are suitable for the quantitative evaluation of fetal myelination. PURPOSE: To optimize a modified Look-Locker inversion recovery (MOLLI) T1 mapping sequence for fetal brain development study. STUDY TYPE: Prospective observational preliminary cohort study. POPULATION: A total of 71 women with normal fetuses divided into mid-pregnancy (gestational age 24-28 weeks, N = 25) and late pregnancy (gestational age > 28 weeks, N = 46) groups. FIELD STRENGTH/SEQUENCE: A 3 T/MOLLI sequence. ASSESSMENT: T1 values were measured in pedunculus cerebri, basal ganglia, thalamus, posterior limb of the internal capsule, temporal white matter, occipital white matter, frontal white matter, and parietal white matter by two radiologists (11 and 16 years of experience, respectively). STATISTICAL TESTS: The Kruskal-Wallis test was used for reginal comparison. For each region of interest (ROI), differences in T1 values between the mid and late pregnancy groups were assessed by the Mann Whitney U test. Pearson correlation coefficients (r) were used to evaluate the correlations between T1 values and gestational age for each ROI. Intraobserver and interobserver agreement was determined by the intraclass correlation coefficient (ICC). A P value <0.05 was considered statistically significant. RESULTS: Interobserver and intraobserver agreements of T1 were good for all ROIs (all ICCs > 0.700). There were significant differences in T1 values between lobal white matter and deep regions, respectively. Significant T1 values differences were found between middle and late pregnancy groups in pedunculus cerebri, basal ganglion, thalamus, posterior limb of the internal capsule, temporal, and occipital white matter. The T1 values showed significantly negative correlations with gestational weeks in pedunculus cerebri (r = -0.80), basal ganglion (r = -0.60), thalamus (r = -0.68), and posterior limb of the internal capsule (r = -0.77). DATA CONCLUSION: The T1 values of fetal brain may be assessed using the MOLLI sequence and may reflect the myelination. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Optimization of the image contrast for the developing fetal brain using 3D radial VIBE sequence in 3 T magnetic resonance imaging.

BACKGROUND: Faster and motion robust magnetic resonance imaging (MRI) sequences are desirable in fetal brain MRI. T1-weighted images are essential for evaluating fetal brain development. We optimized the radial volumetric interpolated breath-hold examination (VIBE) sequence for qualitative T1-weighted images of the fetal brain with improved image contrast and reduced motion sensitivity. MATERIALS AND METHODS: This was an institutional review board-approved prospective study. Thirty-five pregnant subjects underwent fetal brain scan at 3 Tesla MRI. T1-weighted images were acquired using a 3D radial VIBE sequence with flip angles of 6º, 9º, 12º, and 15º. T1-weighted images of Cartesian VIBE sequence were acquired in three of the subjects. Qualitative assessments including image quality and motion artifact severity were evaluated. The image contrast ratio between gray and white matter were measured. Interobserver reliability and intraobserver repeatability were assessed using intraclass correlation coefficient (ICC). RESULTS: Interobserver reliability and intraobserver repeatability universally revealed almost perfect agreement (ICC > 0.800). Significant differences in image quality were detected in basal ganglia (P = 0.023), central sulcus (P = 0.028), myelination (P = 0.007) and gray matter (P = 0.023) among radial VIBE with flip angles 6º, 9º, 12º, 15º. Image quality at the 9º flip angle in radial VIBE was generally better than flip angle of 15º. Radial VIBE sequence with 9º flip angle of gray matter was significantly different by gestational age (GA) before and after 28 weeks (P = 0.036). Quantified image contrast was significantly different among different flip angles, consistent with qualitative analysis of image quality. CONCLUSIONS: Three-dimensional radial VIBE with 9º flip angle provides optimal, stable T1-weighted images of the fetal brain. Fetal brain structure and development can be evaluated using high-quality images obtained using this angle. However, different scanners will achieve different TRs and so the FA should be re-optimized each time a new protocol is employed.

MRI characteristics of the fetal tethered spinal cord: a comparative study.

Purpose: To compare fetuses and children with confirmed tethered cord syndrome to age-matched controls to provide a reference for prenatally identifying tethered spinal cord and to identify salient points on MRI for diagnosis.Materials and Methods: This retrospective study enrolled 13 fetuses and 20 children with tethered cord syndrome, and age-matched counterparts were included as controls. The MRI features including concomitant malformations, position of the conus medullaris, and thickened filum terminale of the two patient groups were evaluated and compared. Levels of the conus medullaris were discriminated between patients and an equivalent number of controls.Results: Various concomitant malformations manifested on the MRI of all patients, and there were differences between the two patient groups. Significant differences of the level of the conus medullaris were found between the fetal and child patients (U, 26.50; Z, -3.87; p < 0.001) and between the normal fetus and child controls (U, 23.50; Z, -4.13; p < 0.001). The position of the conus medullaris was visibly lower in the patient groups than in the control groups. No significant difference in the diameters of the filum terminale was found between the fetal and child patients (p = 0.67).Conclusions: The current study's results indicate that tethered spinal cord syndrome can be diagnosed in utero with MRI combined with several characteristics, particularly the position of the conus medullaris. Special attention should be paid to the gestational age of the fetus because normal changes in spinal cord position occur with gestational development.

[Effects of Sertoli cells and peritubular myoid cells on testosterone synthesis in Leydig cells: Analysis based on the testicular microenvironment].

Recent progress in the studies of testicular microenvironment has provided some new ideas on the diagnosis, treatment and prevention of related diseases. Testosterone, as an important androgen in men, regulates the physiological functions of males. The synthesis of testosterone is an extremely complex process, which mainly takes place in Leydig cells. However, Sertoli cells and testicular peritubular myoid cells, which constitute the testicular microenvironment, also play an essential role in the process of testosterone synthesis. This review focuses on the process of Leydig cells synthesizing testosterone and the effects of Sertoli cells and testicular peritubular myoid cells on testosterone synthesis from the perspective of testicular microenvironment, aiming to provide reference for the treatment and prevention of male diseases.

[Potential mechanisms of Jiarong Tablets in the treatment of late-onset hypogonadism in men: An exploration based on network pharmacology].

OBJECTIVE: To study the therapeutic targets and related signaling pathways of Jiarong Tablets (JRT) in the treatment of late-onset hypogonadism (LOH) in males by network pharmacology, and further analyze its potential action mechanism. METHODS: Using the Chinese Medicine System Pharmacology Analysis Platform (TCMSP), we obtained the active ingredients and therapeutic targets of JRT, disease targets of LOH through the GeneCards and OMIM databases, and drug-disease common targets, followed by drawing a Vennny's diagram of the common targets. We constructed a protein-protein interaction (PPI) network of the common targets using STRING and an intersection network of JRT active ingredients-LOH-targets with Cytoscape 3.7.2, performed GO bio-functional and KEGG enrichment analyses of the common targets using the R-Language software, and identified the potential signaling pathways of JRT acting on LOH. RESULTS: Totally, we obtained 80 bioactive ingredients from JRT and 64 common targets of LOH, with IL-6, INS, AKT1, JUN and MAPK8 as the core targets in the order of the frequency occurrences. GO and KEGG analyses showed that these targets mainly involved the MAPK, HIF-1, Ras and ErbB signaling pathways. CONCLUSION: JRT acts on LOH with multiple targets, through multiple routes and at multiple levels, which is related to the expression of testosterone synthetase, oxidative stress and apoptosis of Leydig cells.

[Establishment and evaluation of a rat model of late-on-set hypogonadism using D-galactose].

OBJECTIVE: To explore the feasibility and duration of establishing a model of late-on-set hypogonadism (LOH) in rats using D-galactose (D-gal) and the optimal concentration of D-gal in modeling. METHODS: Thirty-five 8-week-old male SD rats were randomly divided into seven groups of an equal number to receive intraperitoneal injection of normal saline (normal control) or D-gal at 480 mg/kg/d (high-dose), 240 mg/kg/d (medium-dose) and 120 mg/kg/d (low-dose) for 6 or 8 weeks respectively. Another five 18-month-old SD rats were taken as positive controls. After modeling, the animals were subjected to tail suspension test and mating test, weighed, and then sacrificed for examination of the levels of fasting blood glucose (FBG) and serum testosterone (T), testis index and semen parameters, determination of the expressions of the BMAL1 and NR1D1 proteins in the testis tissue by Western blot, and observation of the pathological and ultrastructural changes in the testis tissue under the light microscope and transmission electron microscope. RESULTS: Compared with the normal controls, the serum T level was significantly decreased in the 6-week medium-dose D-gal (6WMD), 6-week high-dose D-gal (6WHD), 8WMD, 8WHD and positive control groups (P < 0.05), and so were sperm concentration and the percentage of progressively motile sperm (PMS) in the 8WHD and positive control groups (P < 0.05), and the numbers of captures and ejaculations in all the model rats and positive controls (P < 0.05), while the body weight was markedly increased in the 8-week low-dose D-gal (8WLD), 8WMD and 8WHD groups (P < 0.05), and so were the tail suspension time in the 6WHD, 8WHD, 8WMD, 8WLD and positive control groups (P < 0.05) and the FBG level in all the model rats and positive controls (P < 0.05). The expression of the BMAL1 protein was significantly decreased in the 6WHD, 8WLD, 8WMD, 8WHD and positive control groups (P < 0.05), and so was that of NR1D1 in the 8WMD, 8WHD and positive control groups (P < 0.05). Compared with the positive controls, no statistically significant differences were observed in the serum T level in the 6WHD and 8WHD groups (P > 0.05), the testis index in the 8WMD and 8WHD groups (P > 0.05), sperm concentration, percentage of FMS, time of tail suspension and numbers of captures and ejaculations in the 8WHD group (P > 0.05), the level of FBG in the 6WMD, 6WHD, 8WLD, 8WMD and 8WHD groups (P > 0.05), the expression of BMAL1 in the 6WHD, 8WLD, 8WMD and 8WHD groups (P > 0.05), and that of NR1D1 in the 6WLD, 8WMD and 8WHD groups (P > 0.05). Pathological and ultrastructural changes in the testis tissue were observed in all the model rats and positive controls, most significantly in the 8WHD and positive control groups. CONCLUSION: It is feasible to establish an LOH model in male SD rats by intraperitoneal injection of D-gal, most recommendably at the centration of 480 mg/kg/d for 8 weeks.

A novel treatment strategy for lapatinib resistance in a subset of HER2-amplified gastric cancer.

BACKGROUND: Gastric cancer (GC) is one of the leading causes of cancer-related deaths worldwide. Human epidermal growth factor receptor 2 (HER2) amplification occurs in approximately 13-23% of all GC cases and patients with HER2 overexpression exhibit a poor prognosis. Lapatinib, a dual EGFR/HER2 tyrosine kinase inhibitor, is an effective agent to treat HER2-amplified breast cancer but it failed in gastric cancer (GC) clinical trials. However, the molecular mechanism of lapatinib resistance in HER2-amplified GC is not well studied. METHODS: We employed an unbiased, genome-scale screening with pooled CRISPR library on HER2-amplified GC cell lines to identify genes that are associated with resistance to lapatinib. To validate the candidate genes, we applied in vitro and in vivo pharmacological tests to confirm the function of the target genes. RESULTS: We found that loss of function of CSK or PTEN conferred lapatinib resistance in HER2-amplified GC cell lines NCI-N87 and OE19, respectively. Moreover, PI3K and MAPK signaling was significantly increased in CSK or PTEN null cells. Furthermore, in vitro and in vivo pharmacological study has shown that lapatinib resistance by the loss of function of CSK or PTEN, could be overcome by lapatinib combined with the PI3K inhibitor copanlisib and MEK inhibitor trametinib. CONCLUSIONS: Our study suggests that loss-of-function mutations of CSK and PTEN cause lapatinib resistance by re-activating MAPK and PI3K pathways, and further proved these two pathways are druggable targets. Inhibiting the two pathways synergistically are effective to overcome lapatinib resistance in HER2-amplified GC. This study provides insights for understanding the resistant mechanism of HER2 targeted therapy and novel strategies that may ultimately overcome resistance or limited efficacy of lapatinib treatment for subset of HER2 amplified GC.

Cloning and variation of ground state intestinal stem cells.

Stem cells of the gastrointestinal tract, pancreas, liver and other columnar epithelia collectively resist cloning in their elemental states. Here we demonstrate the cloning and propagation of highly clonogenic, 'ground state' stem cells of the human intestine and colon. We show that derived stem-cell pedigrees sustain limited copy number and sequence variation despite extensive serial passaging and display exquisitely precise, cell-autonomous commitment to epithelial differentiation consistent with their origins along the intestinal tract. This developmentally patterned and epigenetically maintained commitment of stem cells is likely to enforce the functional specificity of the adult intestinal tract. Using clonally derived colonic epithelia, we show that toxins A or B of the enteric pathogen Clostridium difficile recapitulate the salient features of pseudomembranous colitis. The stability of the epigenetic commitment programs of these stem cells, coupled with their unlimited replicative expansion and maintained clonogenicity, suggests certain advantages for their use in disease modelling and regenerative medicine.

Short report: factors determining perceived stress among medical staff in radiology departments during the COVID-19 outbreak.

Medical staff in radiology departments faces a higher risk of infection and a heavier workload during the new coronavirus disease (COVID-19) outbreak. High perceived stress levels endanger physical and mental health and affect work efficiency and patient safety. Therefore, it is urgent to understand the perceived stress levels of medical staff and explore its risk factors. We recruited 600 medical staff from the radiology departments of 32 public hospitals in Sichuan Province, China, to evaluate perceived stress scores via a mobile app-based questionnaire. The results showed that the perceived stress level among medical staff in the radiology departments during the COVID-19 outbreak was high and a sense of tension was strongly present. A positive correlation was found between anxiety score and perceived stress. Multivariate analysis showed that risk factors for perceived stress were female, existing anxiety, and fears of being infected at work, an uncontrollable outbreak, and not being able to pay rent or mortgage. Conversely, good knowledge about COVID-19, being unmarried, and working in a higher-grade hospital were protective factors for perceived stress. Therefore, more attention should be given to medical staff in the radiology departments that present the risk factors outlined above. Timely risk assessment of psychological stress and effective intervention measures should be taken for these high-risk groups to keep their perceived stress within normal limits.

[Establishment and evaluation of an AAPH-induced oxidative stress model in mouse Leydig cells in vitro].

OBJECTIVE: To establish a model of oxidative stress (OS) injury in mouse Leydig cells using α-α'-azodiisobutyramidine hydrochloride (AAPH) and evaluate the physiological function. METHODS: In Experiment 1, we treated mouse TM3 Leydig cells with AAPH at 0, 1, 5, 10, 50 and 100 mmol/L for 4, 8 and 24 h respectively and measured the activity of the cells using MTS, their aging by ß-galactoside staining, mitochondrial membrane potential by JC-1 fluorescence and mitochondrial DNA copy number by qPCR. In Experiment 2, we treated the TM3 cells selected in Experiment 1 according to the AAPH concentration range (≤10 mmol/L) with AAPH at 0, 0.1, 0.5, 1, 2, 4, 6, 8 and 10 mmol/L for 24, 48 and 72 h respectively, detected the activity and aging of the cells and the ROS positive rate, and determined the optimal concentration and time of AAPH in inducing OS injury in the TM3 cells. RESULTS: Experiment 1 showed that the survival rate of the TM3 cells was ≥50% in the 4-h 50 mmol/L, 8-h 10 mmol/L and 24-h 5 mmol/L AAPH groups, the initial concentration of AAPH was ≤10 mmol/L, with the action time of ≥24 h. Experiment 2 manifested that in the 24-h 6 mmol/L AAPH group, the survival rate of the TM3 cells was ≥70%, with an ROS positive rate of 56.88%, normal mitochondrial membrane potential, increased number of mtDNA copies, but no senescence. CONCLUSIONS: Treatment with AAPH at the concentration of 6 mmol/L for 24 hours is suitable for induction of OS injury in the TM3 cells.

AggFluor: Fluorogenic Toolbox Enables Direct Visualization of the Multi-Step Protein Aggregation Process in Live Cells.

Aberrantly processed or mutant proteins misfold and assemble into a variety of soluble oligomers and insoluble aggregates, a process that is associated with an increasing number of diseases that are not curable or manageable. Herein, we present a chemical toolbox, AggFluor, that allows for live cell imaging and differentiation of complex aggregated conformations in live cells. Based on the chromophore core of green fluorescent proteins, AggFluor is comprised of a series of molecular rotor fluorophores that span a wide range of viscosity sensitivity. As a result, these compounds exhibit differential turn-on fluorescence when incorporated in either soluble oligomers or insoluble aggregates. This feature allows us to develop, for the first time, a dual-color imaging strategy to distinguish unfolded protein oligomers from insoluble aggregates in live cells. Furthermore, we have demonstrated how small molecule proteostasis regulators can drive formation and disassembly of protein aggregates in both conformational states. In summary, AggFluor is the first set of rationally designed molecular rotor fluorophores that evenly cover a wide range of viscosity sensitivities. This set of fluorescent probes not only change the status quo of current imaging methods to visualize protein aggregation in live cells but also can be generally applied to study other biological processes that involve local viscosity changes with temporal and spatial resolutions.

Hijacking of multiple phospholipid biosynthetic pathways and induction of membrane biogenesis by a picornaviral 3CD protein.

RNA viruses induce specialized membranous structures for use in genome replication. These structures are often referred to as replication organelles (ROs). ROs exhibit distinct lipid composition relative to other cellular membranes. In many picornaviruses, phosphatidylinositol-4-phosphate (PI4P) is a marker of the RO. Studies to date indicate that the viral 3A protein hijacks a PI4 kinase to induce PI4P by a mechanism unrelated to the cellular pathway, which requires Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1, GBF1, and ADP ribosylation factor 1, Arf1. Here we show that a picornaviral 3CD protein is sufficient to induce synthesis of not only PI4P but also phosphatidylinositol-4,5-bisphosphate (PIP2) and phosphatidylcholine (PC). Synthesis of PI4P requires GBF1 and Arf1. We identified 3CD derivatives: 3CDm and 3CmD, that we used to show that distinct domains of 3CD function upstream of GBF1 and downstream of Arf1 activation. These same 3CD derivatives still supported induction of PIP2 and PC, suggesting that pathways and corresponding mechanisms used to induce these phospholipids are distinct. Phospholipid induction by 3CD is localized to the perinuclear region of the cell, the outcome of which is the proliferation of membranes in this area of the cell. We conclude that a single viral protein can serve as a master regulator of cellular phospholipid and membrane biogenesis, likely by commandeering normal cellular pathways.

Multiple poliovirus-induced organelles suggested by comparison of spatiotemporal dynamics of membranous structures and phosphoinositides.

At the culmination of poliovirus (PV) multiplication, membranes are observed that contain phosphatidylinositol-4-phosphate (PI4P) and appear as vesicular clusters in cross section. Induction and remodeling of PI4P and membranes prior to or concurrent with genome replication has not been well studied. Here, we exploit two PV mutants, termed EG and GG, which exhibit aberrant proteolytic processing of the P3 precursor that substantially delays the onset of genome replication and/or impairs virus assembly, to illuminate the pathway of formation of PV-induced membranous structures. For WT PV, changes to the PI4P pool were observed as early as 30 min post-infection. PI4P remodeling occurred even in the presence of guanidine hydrochloride, a replication inhibitor, and was accompanied by formation of membrane tubules throughout the cytoplasm. Vesicular clusters appeared in the perinuclear region of the cell at 3 h post-infection, a time too slow for these structures to be responsible for genome replication. Delays in the onset of genome replication observed for EG and GG PVs were similar to the delays in virus-induced remodeling of PI4P pools, consistent with PI4P serving as a marker of the genome-replication organelle. GG PV was unable to convert virus-induced tubules into vesicular clusters, perhaps explaining the nearly 5-log reduction in infectious virus produced by this mutant. Our results are consistent with PV inducing temporally distinct membranous structures (organelles) for genome replication (tubules) and virus assembly (vesicular clusters). We suggest that the pace of formation, spatiotemporal dynamics, and the efficiency of the replication-to-assembly-organelle conversion may be set by both the rate of P3 polyprotein processing and the capacity for P3 processing to yield 3AB and/or 3CD proteins.

Suppression of complement component 2 expression by hepatitis B virus contributes to the viral persistence in chronic hepatitis B patients.

Previously, we identified rare missense mutations of complement component 2 (C2) to be associated with chronic hepatitis B (CHB) by exome sequencing. However, up to now, little is known about the role of C2 in CHB. In the present study, we aimed to perform preliminary exploration about the underlying role of C2 in CHB. Serum samples from 113 CHB patients and 30 healthy controls, and liver biopsy samples from 5 CHB patients and 3 healthy controls were obtained from the Third Affiliated Hospital of Sun Yat-sen University between January 2018 and January 2020. HepG2.2.15 and HepG2-NTCP cells infected with HBV were used to examine the influence of HBV infection on C2 expression. IFN-treated HepG2.2.15 cells were used to assess the effect of IFN on C2 expression. C2-overexpressing or C2-silencing HepG2.2.15 cells were constructed to evaluate the effect of C2 on HBV infection. Western blot and RT-qPCR were used to measure C2 expression in biopsy samples. HBeAg and HBsAg in culture medium and C2 of serum samples were measured by ELISA. HBV-DNA was measured by RT-qPCR. GSE84044, GSE54747 and GSE27555 were downloaded from GEO. C2 expression in liver tissue and serum was significantly lower in CHB patients compared to healthy controls, and significantly higher C2 expression was found in CHB patients with lower ALT, AST, Scheuer grade and stages compared to CHB patients with higher ALT, AST, Scheuer grades and Scheuer stage. Besides, HBV infection could decrease C2 expression by increasing expression of Sp1 and reducing expression of HDAC4. Moreover, C2 could enhance the anti-virus effect of IFN on HepG2.2.15 cells and also inhibit HBV replication in HepG2.2.15 cells by inhibition of p38-MAPK signalling pathway. In conclusion, HBV may promote viral persistence in CHB patients by inhibiting C2 expression.

Evidence for a Novel Endometrioid Carcinogenic Sequence in the Fallopian Tube With Unique Beta-Catenin Expression.

Epithelial proliferations in the fallopian tube have been characterized by some as stem cell outgrowths (SCOUTs) and divided into type I and type II. Type II SCOUTs exhibit diffuse cellular beta-catenin nuclear staining (ß-catenin), implying a CTNNB1 mutation. SCOUTs are more common in perimenopausal and postmenopausal women and are associated with ovarian cancer but have not been linked directly to malignancy. We analyzed type II SCOUTs in various gynecologic conditions, and searched for endometrioid atypical hyperplasias (tubal endometrioid intraepithelial neoplasia) or adenocarcinomas in the tube. ß-catenin SCOUT frequency in cases of neoplasia was 66.7% per case and 30.7% per nonfimbrial cross-section for uterine endometrioid carcinomas versus 25% and 13.3% for controls, respectively (P=0.02 and 0.09). Multiple (3 or more) ß-catenin SCOUTs in a single section were uncommon; 6 of 9 were associated with a carcinoma or proliferative lesion in the endometrium. Tubal endometrioid intraepithelial neoplasia/atypical hyperplasia displayed complex growth, including focal cribriform growth patterns and squamous morules. Two cases of type II SCOUTs associated with tubal endometrioid intraepithelial neoplasia/atypical hyperplasia and/or adenocarcinomas in the fallopian tube were identified, both of which coexisted with a separate endometrioid adenocarcinoma, one with bilateral ovarian endometrioid adenocarcinomas. Both benign and neoplastic tubal lesions were ß-catenin. This report is the first to link components of a unique ß-catenin endometrioid carcinogenic sequence in the fallopian tube. It further emphasizes the multifocal nature of endometrioid neoplasia in the female genital tract and poses questions regarding the frequency and biologic underpinnings of ß-catenin proliferations in the oviduct.