Intensity-Modulated Radiotherapy (IMRT) for the Treatment of Cushing's Disease

PURPOSE/OBJECTIVE(S)

Aim to investigate the efficacy and toxicity of IMRT in treating Cushing's Disease (CD).

MATERIALS/METHODS

A total of 78 of 115 patients with CD treated with IMRT at our institute from April 2012 to August 2021 were included in the study. The radiation doses were usually 45-50 Gy in 25 fractions. After IMRT, endocrine evaluations were performed every 6 months and magnetic resonance imaging (MRI) annually. Endocrine remission was defined as suppression of 1 mg dexamethasone test (DST) or normal 24-hour urinary free cortisol level (24hUFC). Endocrine recurrence was considered when patients who have reached hormonal remission showed no suppression of 1 mg DST and relapse of clinical features. The outcome of endocrine remission, tumor control and complications were retrieved from medical record.

RESULTS

At a median follow-up time of 36.8 months, the endocrine remission rate at 1, 2, 3 and 5 years were 28.5%, 50.2%, 62.5% and 74.0%, respectively. The median time to remission was 24 months (95% CI: 14.0-34.0). Endocrine recurrence was found in 5 patients (13.5%) till the last follow-up. The recurrence-free rate at 1, 2, 3 and 5 years after endocrine remission was 98.2%, 93.9%, 88.7% and 88.7%, respectively. The tumor control rate was 98%. The overall incidence of new onset hypopituitarism was 23.1%, with hypothyroidism serving as the most common individual axis deficiency. Univariate analysis indicated that only higher Ki-67 index (P = 0.044) was significant favorable factors for endocrine remission. But no prognostic factors for endocrine remission were found in the multivariate analysis.

CONCLUSION

IMRT was a highly effective second-line therapy with low side effect profile for CD patients. Endocrine remission, tumor control and recurrence rates were comparable to previous reports on FRT and SRS.

STAMP-Based Digital CRISPR-Cas13a for Amplification-Free Quantification of HIV-1 Plasma Viral Loads

Quantification of HIV RNA in plasma is critical for identifying the disease progression and monitoring the effectiveness of antiretroviral therapy. While RT-qPCR has been the gold standard for HIV viral load quantification, digital assays could provide an alternative calibration-free absolute quantification method. Here, we reported a Self-digitization Through Automated Membrane-based Partitioning (STAMP) method to digitalize the CRISPR-Cas13 assay (dCRISPR) for amplification-free and absolute quantification of HIV-1 viral RNAs. The HIV-1 Cas13 assay was designed, validated, and optimized. We evaluated the analytical performances with synthetic RNAs. With a membrane that partitions ∼100 nL of reaction mixture (effectively containing 10 nL of input RNA sample), we showed that RNA samples spanning 4 orders of dynamic range between 1 fM (∼6 RNAs) to 10 pM (∼60k RNAs) could be quantified as fast as 30 min. We also examined the end-to-end performance from RNA extraction to STAMP-dCRISPR quantification using 140 μL of both spiked and clinical plasma samples. We demonstrated that the device has a detection limit of approximately 2000 copies/mL and can resolve a viral load change of 3571 copies/mL (equivalent to 3 RNAs in a single membrane) with 90% confidence. Finally, we evaluated the device using 140 μL of 20 patient plasma samples (10 positives and 10 negatives) and benchmarked the performance with RT-PCR. The STAMP-dCRISPR results agree very well with RT-PCR for all negative and high positive samples with C_t < 32. However, the STAMP-dCRISPR is limited in detecting low positive samples with C_t > 32 due to the subsampling errors. Our results demonstrated a digital Cas13 platform that could offer an accessible amplification-free quantification of viral RNAs. By further addressing the subsampling issue with approaches such as preconcentration, this platform could be further exploited for quantitatively determining viral load for an array of infectious diseases.

Wnt signaling directs human pluripotent stem cells into vascularized cardiac organoids with chamber-like structures

Heart diseases are leading cause of death around the world. Given their unique capacity to self-renew and differentiate into all types of somatic cells, human pluripotent stem cells (hPSCs) hold great promise for heart disease modeling and cardiotoxic drug screening. hPSC-derived cardiac organoids are emerging biomimetic models for studying heart development and cardiovascular diseases, but it remains challenging to make mature organoids with a native-like structure in vitro. In this study, temporal modulation of Wnt signaling pathway co-differentiated hPSCs into beating cardiomyocytes and cardiac endothelial-like cells in 3D organoids, resulting in cardiac endothelial-bounded chamber formation. These chambered cardiac organoids exhibited more mature membrane potential compared to cardiac organoids composed of only cardiomyocytes. Furthermore, a better response to toxic drugs was observed in chamber-contained cardiac organoids. In summary, spatiotemporal signaling pathway modulation may lead to more mature cardiac organoids for studying cardiovascular development and diseases.

Fabricating 3-dimensional human brown adipose microtissues for transplantation studies

Transplanting cell cultured brown adipocytes (BAs) represents a promising approach to prevent and treat obesity (OB) and its associated metabolic disorders, including type 2 diabetes mellitus (T2DM). However, transplanted BAs have a very low survival rate in vivo. The enzymatic dissociation during the harvest of fully differentiated BAs also loses significant cells. There is a critical need for novel methods that can avoid cell death during cell preparation, transplantation, and in vivo. Here, we reported that preparing BAs as injectable microtissues could overcome the problem. We found that 3D culture promoted BA differentiation and UCP-1 expression, and the optimal initial cell aggregate size was 100 μm. The microtissues could be produced at large scales via 3D suspension assisted with a PEG hydrogel and could be cryopreserved. Fabricated microtissues could survive in vivo for long term. They alleviated body weight and fat gain and improved glucose tolerance and insulin sensitivity in high-fat diet (HFD)-induced OB and T2DM mice. Transplanted microtissues impacted multiple organs, secreted protein factors, and influenced the secretion of endogenous adipokines. To our best knowledge, this is the first report on fabricating human BA microtissues and showing their safety and efficacy in T2DM mice. The proposal of transplanting fabricated BA microtissues, the microtissue fabrication method, and the demonstration of efficacy in T2DM mice are all new. Our results show that engineered 3D human BA microtissues have considerable advantages in product scalability, storage, purity, safety, dosage, survival, and efficacy.

Maintenance effects of a gamification intervention on motivation and physical activity in patients with coronary heart disease: intermediate results of a randomized controlled trial

Background

Despite the benefits of cardiac rehabilitation and secondary prevention, patients with coronary heart disease frequently fail to meet their daily physical activity goals. When one is stuck in a cycle of bad habits, changing one's behavior can be very challenging. One of the difficulties to maintaining a healthy lifestyle may be a lack of motivation. The use of game design elements (such as points, leaderboards, progress bars, and badges) in non-game contexts to promote motivation and engagement is known as gamification. It could be a powerful tool for encouraging patients to engage in physical activity. However, solid ideas that utilize the fundamental experience and psychological impacts of gaming mechanics must be built upon.

Purpose

The aim of this study is to look into the impact of a smartphone-based gamification intervention on physical activity engagement and other related psychological outcomes in patients with coronary heart disease, as well as the 24-week maintenance of effects beyond the 12-week intervention.

Methods

Participants with coronary heart disease were randomly assigned to three groups (control group, individual group and team group). The individual and team groups received gamified behavior intervention based on behavioral economic principles. Based on the Individual group, the team earned social incentives (collaboration). The intervention lasted 12 weeks, with another 12 weeks of follow-up. The primary outcomes included the change in daily steps and the proportion of patient-days that step goals achieved. The secondary outcomes included competence, autonomous, relatedness and autonomous motivation.

Results

The follow-up period has now been completed by 65 participants (mean age 52.8+10.3, 18.2% female) completed the follow-up period. Compared with the control group (n=17), participants in the individual group (n=25) had a significantly greater increase in mean daily steps from baseline during the intervention group (difference 956; 95% CI, 243–1623; P&lt;0.01), and had a significantly greater proportion of patient-days that step goals achieved (difference 0.35; 95% CI, 0.03–0.12; P&lt;0.001), competence (difference 0.5, 95% CI, 0.3–0.7; P&lt;0.001), autonomous motivation (difference 3.2; 95% CI, 2.0–4.0; P&lt;0.001). However, no significant difference of change in step counts was found between team group (n=23) and control group. During the follow-up period, mean daily steps and autonomous motivation in the individual declined but remained significantly greater than that in the control arm compared with baseline (steps: difference 452; 95% CI, 138–818; P&lt;0.05) (motivation: difference 1.2; 95% CI, 0.3–1.8; P&lt;0.05).

Conclusions

A smartphone-based gamification intervention was found to be an effective strategy to enhance motivation and physical activity engagement, as well as having a great maintenance effect.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work is financially supported by a Construction Programme of Independent Innovation Ability of Community Health Nursing Engineering Laboratory in Jilin Province (Study code: 2020C038-8) awarded to FL.

Engineering chimeric antigen receptor neutrophils from human pluripotent stem cells for targeted cancer immunotherapy

Neutrophils, the most abundant white blood cells in circulation, are closely related to cancer development and progression. Healthy primary neutrophils present potent cytotoxicity against various cancer cell lines through direct contact and via generation of reactive oxygen species. However, due to their short half-life and resistance to genetic modification, neutrophils have not yet been engineered with chimeric antigen receptors (CARs) to enhance their antitumor cytotoxicity for targeted immunotherapy. Here, we genetically engineered human pluripotent stem cells with synthetic CARs and differentiated them into functional neutrophils by implementing a chemically defined platform. The resulting CAR neutrophils present superior and specific cytotoxicity against tumor cells both in vitro and in vivo. Collectively, we established a robust platform for massive production of CAR neutrophils, paving the way to myeloid cell-based therapeutic strategies that would boost current cancer-treatment approaches.

Neutrophils are important innate immune cells that mediate both protumor and antitumor activities. Chang et al. genetically engineer human pluripotent stem cells to produce chimeric antigen receptor (CAR) neutrophils that display superior antitumor activities and improve survival in an in situ glioblastoma xenograft model.

Temporal Expression of Transcription Factor ID2 Improves Natural Killer Cell Differentiation from Human Pluripotent Stem Cells

Natural killer (NK) cells are one type of innate lymphoid cells, and NK cell-based immunotherapy serves as a potentially curative therapy for cancers. However, the lack of reliable resources for a large amount of NK cells required for clinical infusion has limited the broader application of NK cells in targeted immunotherapy. Substantial effort has thus been made to generate NK-like cells from human pluripotent stem cells (hPSCs), but detailed molecular mechanisms regulating NK cell differentiation remain elusive, preventing us from developing robust strategies for NK cell production. Here, we genetically engineered hPSCs with inducible overexpression of transcription factors NFIL3, ID2, or SPI1 via CRISPR/Cas9-mediated gene knock-in and investigated their temporal roles during NK cell differentiation. Our results demonstrated ID2 overexpression significantly promoted NK cell generation compared with NFIL3 and SPI1 overexpression under a chemically defined, feeder-free culture condition. The resulting ID2 hPSC-derived NK cells exhibited various mature NK-specific markers and displayed effective tumor-killing activities, comparable to NK cells derived from wildtype hPSCs. Our study provides a new platform for efficient NK cell production, serving as a realistic off-the-shelf cell source for targeted cancer immunotherapy.

Chemically-defined generation of human hemogenic endothelium and definitive hematopoietic progenitor cells

Human hematopoietic stem cells (HSCs), which arise from aorta-gonad-mesonephros (AGM), are widely used to treat blood diseases and cancers. However, a technique for their robust generation in vitro is still missing. Here we show temporal manipulation of Wnt signaling is sufficient and essential to induce AGM-like hematopoiesis from human pluripotent stem cells. TGFβ inhibition at the stage of aorta-like SOX17⁺CD235a^- hemogenic endothelium yielded AGM-like hematopoietic progenitors, which closely resembled primary cord blood HSCs at the transcriptional level and contained diverse lineage-primed progenitor populations via single cell RNA-sequencing analysis. Notably, the resulting definitive cells presented lymphoid and myeloid potential in vitro; and could home to a definitive hematopoietic site in zebrafish and rescue bloodless zebrafish after transplantation. Engraftment and multilineage repopulating activities were also observed in mouse recipients. Together, our work provided a chemically-defined and feeder-free culture platform for scalable generation of AGM-like hematopoietic progenitor cells, leading to enhanced production of functional blood and immune cells for various therapeutic applications.

Laser-induced graphene non-enzymatic glucose sensors for on-body measurements

Non-enzymatic glucose sensors outperform enzymatic ones in terms of cost, sensitivity, stability, and operating duration. Though highly sensitive, it is still desirable to further improve the sensitivity of non-enzymatic glucose sensors to detect a trace amount of glucose in sweat and other biofluids. Among the demonstrated effective approaches using bimetals or 3D porous structures, the porous laser-induced graphene (LIG) on flexible polymers showcases good conductivity and a simple fabrication process for the integration of sensing materials. The uniform electroless plating of the nickel and gold layer on LIG electrodes demonstrates significantly enhanced sensitivity and a large linear range for glucose sensing. The sensor with the porous LIG foam exhibits a high sensitivity of 1080 μA mM-1 cm-2, whereas a further increased sensitivity of 3500 μA mM-1 cm-2 is obtained with LIG fibers (LIGF). Impressively, a large linear range (0-30 mM) can be achieved by changing the bias voltage from 0.5 to 0.1 V due to the Au coating. Because the existing non-enzymatic glucose sensors are limited to use in basic solutions, their application in wearable electronics is elusive. In addition to the reduced requirement for the basic solution, this work integrates a porous encapsulating reaction cavity containing alkali solutions with a soft, skin-interfaced microfluidic component to provide integrated microfluidic non-enzymatic glucose sensors for sweat sampling and glucose sensing. The accurate glucose measurements from the human sweat and cell culture media showcase the practical utility, which opens up opportunities for the non-enzymatic glucose sensors in wearable electronics.

Male urethral diverticulum squamous cell carcinoma containing a calculus: a rare entity

Male urethral diverticula with calculi have a low incidence. It is extremely rare when the diverticulum accompanied with carcinoma. We report a case of diverticulum of the male urethra containing giant calculi which developed into squamous cell carcinoma. The patient initially presented with lower urinary tract symptoms and a hard, painless perineal mass. We believe that the process of diagnosis and treatment is of great significance in clinical practice.

Optogenetic-mediated cardiovascular differentiation and patterning of human pluripotent stem cells

Precise spatial and temporal regulation of dynamic morphogen signals during human development governs the processes of cell proliferation, migration, and differentiation to form organized tissues and organs. Tissue patterns spontaneously emerge in various human pluripotent stem cell (hPSC) models. However, the lack of molecular methods for precise control over signal dynamics limits the reproducible production of tissue patterns and a mechanistic understanding of self-organization. We recently implemented an optogenetic-based OptoWnt platform for light-controllable regulation of Wnt/β-catenin signaling in hPSCs for in vitro studies. Using engineered illumination devices to generate light patterns and thus precise spatiotemporal control over Wnt activation, here we triggered spatially organized transcriptional changes and mesoderm differentiation of hPSCs. In this way, the OptoWnt system enabled robust endothelial cell differentiation and cardiac tissue patterning in vitro. Our results demonstrate that spatiotemporal regulation of signaling pathways via synthetic OptoWnt enables instructive stem cell fate engineering and tissue patterning.

Association between type 1 diabetes mellitus and reduced bone mineral density in children: a meta-analysis

In this meta-analysis, we analyzed 9 cross-sectional studies for an association between type 1 diabetes mellitus (T1DM) and bone mineral density (BMD) in children. We found that BMD Z-scores were significantly reduced in children with T1DM.

INTRODUCTION

Recent cross-sectional studies have examined how T1DM influences bone health in children and adolescents, but the relationship between T1DM and BMD remains unclear due to conflicting reports.

METHODS

In this meta-analysis, we systematically searched PubMed, Cochrane library, and Web of Science databases (for publications through March 12, 2020), and calculated weight mean difference (WMD) along with 95% confidence intervals (CI) using a random-effects model. Heterogeneity was evaluated using the I² method. The Newcastle-Ottawa Scale was used to assess the quality of the included studies.

RESULTS

Data were analyzed from 9 eligible studies, including a total of 1522 children and adolescents. These data were tested for an association between T1DM and BMD. This analysis found a significant decrease in BMD Z-score in the whole body (pooled WMD, - 0.47, 95% CI, - 0.92 to - 0.02, I² = 80.2%) and lumbar spine (pooled WMD, - 0.41, 95% CI, - 0.69 to - 0.12, I² = 80.3%) in children and adolescents with T1DM, which was consistent in published studies from Asia and South America, but inconsistent in the North America and Europe. Importantly, the differences in BMD Z-scores were independent of age, level of glucose control (HbA1c), and prepubertal stage. Sensitivity analyses did not modify these findings. Funnel plot and the Egger test did not reveal significant publication bias.

CONCLUSION

This meta-analysis suggests that T1DM may play a role in decreasing BMD Z-scores in the whole body and lumbar spine in children.

[The relationship between HPV integration and prognosis of cervical cancer]

Objective: To investigate the relationship between human papillomavirus (HPV) integration and prognosis of cervical cancer patients. Methods: The data of 82 patients with cervical cancer treated in the Radiotherapy Department of Peking Union Medical College Hospital from October 2004 to June 2012 were retrospectively analyzed.The patients were divided into poor prognosis group (recurrence or metastasis after surgery and adjuvant radiotherapy) and good prognosis group based on a propensity score matching strategy.The HPV integration of the two groups were detected by whole exome sequencing to determine whether the integration sites were located in the common fragile sites (CFSs). HPV integration and integration into CFSs were compared between the two groups. Results: Among the enrolled 82 patients, 37 were divided in poor survival group and 45 in good survival group. A total of 90 integration breakpoints were identified, 30 of them occurred in poor prognosis group and 60 occurred in good prognosis group. In the poor prognosis group, HPV integration occurred in 20 patients, 13 of them were inserted in CFSs of 11 patients, and the numbers in good prognosis group were 26, 17, 11, respectively. There were no significantly statistical differences in the number of HPV integration events (P=0.289), HPV integration patients (P=0.735), CFSs integration events (P=0.427), and CFSs integration patients (P=0.591) between the two groups. In poor prognosis group, more CFSs integration events occurred in patients with metastasis than those in patients with only local recurrence (9 vs 2, P=0.003). Conclusions: No significant differences are observed in HPV integration and HPV integration into CFSs between cervical cancer patients with different prognoses. HPV integration into CFSs may be associated with distant metastasis.

High-affinity mutant Interleukin-13 targeted CAR T cells enhance delivery of clickable biodegradable fluorescent nanoparticles to glioblastoma

Glioblastoma (GBM), the deadliest form of brain cancer, presents long-standing problems due to its localization. Chimeric antigen receptor (CAR) T cell immunotherapy has emerged as a powerful strategy to treat cancer. IL-13-receptor-α2 (IL13Rα2), present in over 75% of GBMs, has been recognized as an attractive candidate for anti-glioblastoma therapy. Here, we propose a novel multidisciplinary approach to target brain tumors using a combination of fluorescent, therapeutic nanoparticles and CAR T cells modified with a targeted-quadruple-mutant of IL13 (TQM-13) shown to have high binding affinity to IL13Rα2-expressing glioblastoma cells with low off-target toxicity. Azide-alkyne cycloaddition conjugation of nanoparticles to the surface of T cells allowed a facile, selective, and high-yielding clicking of the nanoparticles. Nanoparticles clicked onto T cells were retained for at least 8 days showing that the linkage is stable and promising a suitable time window for in vivo delivery. T cells clicked with doxorubicin-loaded nanoparticles showed a higher cytotoxic effect in vitro compared to bare T cells. In vitro and in vivo T cells expressing TQM-13 served as delivery shuttles for nanoparticles and significantly increased the number of nanoparticles reaching brain tumors compared to nanoparticles alone. This work represents a new platform to allow the delivery of therapeutic nanoparticles and T cells to solid tumors.

Epidemiologic and clinical characteristics of 91 hospitalized patients with COVID-19 in Zhejiang, China: a retrospective, multi-centre case series

BACKGROUND

Recent studies have focused on initial clinical and epidemiological characteristics of the coronavirus disease 2019 (COVID-19), which is the mainly revealing situation in Wuhan, Hubei.

AIM

This study aims to reveal more data on the epidemiological and clinical characteristics of COVID-19 patients outside of Wuhan, Zhejiang, China.

DESIGN

This study was a retrospective case series.

METHODS

Eighty-eight cases of laboratory-confirmed and three cases of clinically confirmed COVID-19 were admitted to five hospitals in Zhejiang province, China. Data were collected from 20 January 2020 to 11 February 2020.

RESULTS AND DISCUSSION

Of all 91 patients, 88 (96.70%) were laboratory-confirmed COVID-19 with throat swab samples that tested positive for SARS-Cov-2, three (3.30%) cases were clinically diagnosed. The median age of the patients was 50 (36.5-57) years, and female accounted for 59.34%. In this sample, 40 (43.96%) patients had contracted the disease from local cases, 31 (34.07%) patients had been to Wuhan/Hubei, eight (8.79%) patients had contacted with people from Wuhan, and 11 (12.09%) patients were diagnosed after having flown together in the same flight with no passenger that could later be identified as the source of infection. In particular within the city of Ningbo, 60.52% cases can be traced back to an event held in a temple. The most common symptoms were fever (71.43%), cough (60.44%) and fatigue (43.96%). The median of incubation period was 6 (interquartile range 3-8) days and the median time from the first visit to a doctor to the confirmed diagnosis was 1 (1-2) days. According to the chest computed tomography scans, 67.03% cases had bilateral pneumonia.

CONCLUSIONS

Social activity cluster, family cluster and flying alongside with persons already infected with COVID-19 were how people got infected with COVID-19 in Zhejiang.

Cytological mechanism of astragaloside IV in promoting repair of bone defects

To explore the possible cytological mechanism underlying the role of Astragaloside IV in promoting the repair of bone defects, osteoblasts were cultured in vitro and identified using inverted phase contrast microscopy, alkaline phosphatase (ALP) staining and alizarin red staining.

Scale-invariant magnetoresistance in a cuprate superconductor

The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La_2-x Sr _x CuO₄ cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.

[Survival and prognostic factors analysis of primitive neuroectodermal tumor]

Objective: To investigate the clinical features and prognosis of primitive neuroectodermal tumor (PNET). Methods: The clinical data of 99 patients with PNET from February 1, 1998 to February 1, 2017 were retrospectively analyzed. Univariate analysis was performed using Kaplan-Meier and Log rank test. Multiviate Cox regression was applied to analyzed independent prognostic factor for patient survival. Results: Among the 99 patients, 81 were peripheral PNET(pPNET) and 18 were central PNET (cPNET) . Biopsy was performed exclusively in 16 cases, with R0 resection in 61 cases, with R1 resection in 4 cases, and with R2 resection in 18 cases. Twelve patients underwent surgery only, nine had chemotherapy only, and one received radiotherapy only. There were 72 patients who had combined treatment including chemotherapy, and 48 patients had combined therapy including radiotherapy. The one-year, three-year and five-year overall survival(OS) rates of the 99 PNET patients were 79.2%, 63.9% and 56.1% respectively, and median OS time was 14.0 months. The one-year, three-year and five-year progression free survival (PFS) rates of these patients were 42.7%, 25.7% and 19.8% respectively, and median PFS time was 8.0 months. The univariate analysis revealed that lymph node metastasis, surgical resection, numbers of cycles of chemotherapy and radiotherapy dose were the main factors affecting the OS (all P<0.05). Gender, age, lymph node metastasis, staging, and chemotherapy cycles were related to PFS in PNET patients (P<0.05). Multivariate analysis showed that the degree of surgical resection, chemotherapy cycle, and radiotherapy dosage were independent influencing factors of OS in PNET patients (risk ratio=1.856, 0.398, and 0.408, respectively, all P<0.05), and gender was an independent factor influencing PFS in PNET patients (risk ratio=0.494, P<0.05). Conclusions: Comprehensive therapy is the main therapy for PNET patients. The surgical resection, cycles of chemotherapy and radiotherapy dosage are independent prognostic factors for patient's OS.

Bulk Fermi Surfaces of the Dirac Type-II Semimetallic Candidates MAl_{3} (Where M=V, Nb, and Ta)

We report a de Haas-van Alphen (dHvA) effect study on the Dirac type-II semimetallic candidates MAl_{3} (where, M=V, Nb and Ta). The angular dependence of their Fermi surface (FS) cross-sectional areas reveals a remarkably good agreement with our first-principles calculations. Therefore, dHvA supports the existence of tilted Dirac cones with Dirac type-II nodes located at 100, 230 and 250 meV above the Fermi level ϵ_{F} for VAl_{3}, NbAl_{3} and TaAl_{3} respectively, in agreement with the prediction of broken Lorentz invariance in these compounds. However, for all three compounds we find that the cyclotron orbits on their FSs, including an orbit nearly enclosing the Dirac type-II node, yield trivial Berry phases. We explain this via an analysis of the Berry phase where the position of this orbit, relative to the Dirac node, is adjusted within the error implied by the small disagreement between our calculations and the experiments. We suggest that a very small amount of doping could displace ϵ_{F} to produce topologically nontrivial orbits encircling their Dirac node(s).

Directed differentiation and long-term maintenance of epicardial cells derived from human pluripotent stem cells under fully defined conditions

Here, we describe how to efficiently direct human pluripotent stem cells (hPSCs) differentiation into self-renewing epicardial cells in a completely defined, xeno-free system by temporal modulation of regulators of canonical Wnt signaling. Appropriate differentiation-stage-specific application of Gsk3 inhibitor, Wnt inhibitor, and Gsk3 inhibitor (GiWiGi) is sufficient to produce cells expressing epicardial markers and exhibiting epicardial phenotypes with a high yield and purity from multiple hPSC lines in 16 d. Characterization of differentiated cells is performed via flow cytometry and immunostaining to assess quantitative expression and localization of epicardial cell-specific proteins. In vitro differentiation into fibroblasts and smooth muscle cells (SMCs) is also described. In addition, culture in the presence of transforming growth factor (TGF)-β inhibitors allows long-term expansion of hPSC-derived epicardial cells (for at least 25 population doublings). Functional human epicardial cells differentiated via this protocol may constitute a potential cell source for heart disease modeling, drug screening, and cell-based therapeutic applications.

Human pluripotent stem cell-derived epicardial progenitors can differentiate to endocardial-like endothelial cells

During heart development, epicardial progenitors contribute various cardiac lineages including smooth muscle cells, cardiac fibroblasts, and endothelial cells. However, their specific contribution to the human endothelium has not yet been resolved, at least in part due to the inability to expand and maintain human primary or pluripotent stem cell (hPSC)‐derived epicardial cells. Here we first generated CDH5‐2A‐eGFP knock‐in hPSC lines and differentiated them into self‐renewing WT1+ epicardial cells, which gave rise to endothelial cells upon VEGF treatment in vitro. In addition, we found that the percentage of endothelial cells correlated with WT1 expression in a WT1‐2A‐eGFP reporter line. The resulting endothelial cells displayed many endocardium‐like endothelial cell properties, including high expression levels of endocardial‐specific markers, nutrient transporters and well‐organized tight junctions. These findings suggest that human epicardial progenitors may have the capacity to form endocardial endothelium during development and have implications for heart regeneration and cardiac tissue engineering.

An all-in-one, Tet-On 3G inducible PiggyBac system for human pluripotent stem cells and derivatives

Human pluripotent stem cells (hPSCs) offer tremendous promise in tissue engineering and cell-based therapies due to their unique combination of two properties: pluripotency and unlimited proliferative capacity. However, directed differentiation of hPSCs to clinically relevant cell lineages is needed to achieve the goal of hPSC-based therapies. This requires a deep understanding of how cell signaling pathways converge on the nucleus to control differentiation and the ability to dissect gene function in a temporal manner. Here, we report the use of the PiggyBac transposon and a Tet-On 3G drug-inducible gene expression system to achieve versatile inducible gene expression in hPSC lines. Our new system, XLone, offers improvement over previous Tet-On systems with significantly reduced background expression and increased sensitivity to doxycycline. Transgene expression in hPSCs is tightly regulated in response to doxycycline treatment. In addition, the PiggyBac elements in our XLone construct provide a rapid and efficient strategy for generating stable transgenic hPSCs. Our inducible gene expression PiggyBac transposon system should facilitate the study of gene function and directed differentiation in human stem cells.

Long-term self-renewing human epicardial cells generated from pluripotent stem cells under defined xeno-free conditions

The epicardium contributes both multi-lineage descendants and paracrine factors to the heart during cardiogenesis and cardiac repair, underscoring its potential for cardiac regenerative medicine. Yet little is known about the cellular and molecular mechanisms that regulate human epicardial development and regeneration. Here, we show that the temporal modulation of canonical Wnt signaling is sufficient for epicardial induction from 6 different human pluripotent stem cell (hPSC) lines, including a WT1-2A-eGFP knock-in reporter line, under chemically-defined, xeno-free conditions. We also show that treatment with transforming growth factor beta (TGF-β)-signalling inhibitors permitted long-term expansion of the hPSC-derived epicardial cells, resulting in a more than 25 population doublings of WT1+ cells in homogenous monolayers. The hPSC-derived epicardial cells were similar to primary epicardial cells both in vitro and in vivo, as determined by morphological and functional assays, including RNA-seq. Our findings have implications for the understanding of self-renewal mechanisms of the epicardium and for epicardial regeneration using cellular or small-molecule therapies.

Comparison of clinicopathological features and prognosis of gastric cancer located in the lesser and greater curve

PURPOSE

Little is known about the features of gastric cancer located in the lesser and greater curve. This study aims to investigate the clinicopathological features and prognosis of gastric cancer located in the lesser and greater curve.

PATIENTS

From September 2008 to March 2015, 780 gastric cancer patients were enrolled in the present study. The associations between locations and features of patients were analyzed.

RESULTS

There were 571 male (73.2 %) and 209 female (26.8 %) patients. The median age was 56 years (ranged 21-86). There were 684 tumors located in the lesser curve (87.7 %) and 96 located in the greater curve (12.3 %). The incidence of melena was significantly lower in patients with tumors located in the lesser curve than that in the greater curve (8.5 vs 15.6 %, P = 0.024). The median size of tumors in the lesser curve was significantly larger than that in the greater curve (5.0 (0.3-15) vs 4.0 cm (0.5-15), P = 0.001). The remaining clinicopathological features were comparable between the two groups (all P > 0.05). Tumor location was not a risk factor for the prognosis of gastric cancer by univariate and multivariate analysis (both P > 0.05). The postoperative complications (all P > 0.05) and prognoses (P = 0.279) were comparable between tumors located in the lesser and greater curve.

CONCLUSIONS

The ratio of gastric cancer located in the lesser to greater curve was 7.1:1. Compared with tumors located in the greater curve, the incidence of melena was significantly lower and the tumor size was significantly larger in tumors located in the lesser curve. The prognoses were comparable between tumors located in the lesser and greater curve.

Generation of Epithelial Cell Populations from Human Pluripotent Stem Cells Using a Small-Molecule Inhibitor of Src Family Kinases

Human pluripotent stem cells (hPSCs), under the right conditions, can be engineered to generate populations of any somatic cell type. Knowledge of what mechanisms govern differentiation towards a particular lineage is often quite useful for efficiently producing somatic cell populations from hPSCs. Here, we have outlined a strategy for deriving populations of simple epithelial cells, as well as more mature epidermal keratinocyte progenitors, from hPSCs by exploiting a mechanism previously shown to direct epithelial differentiation of hPSCs. Specifically, we describe how to direct epithelial differentiation of hPSCs using an Src family kinase inhibitor, SU6656, which has been shown to modulate β-catenin translocation to the cell membrane and thus promote epithelial differentiation. The differentiation platform outlined here produces cells with the ability to terminally differentiate to epidermal keratinocytes in culture through a stable simple epithelial cell intermediate that can be expanded in culture for numerous (>10) passages.

Loss of CSL Unlocks a Hypoxic Response and Enhanced Tumor Growth Potential in Breast Cancer Cells

Notch signaling is an important regulator of stem cell differentiation. All canonical Notch signaling is transmitted through the DNA-binding protein CSL, and hyperactivated Notch signaling is associated with tumor development; thus it may be anticipated that CSL deficiency should reduce tumor growth. In contrast, we report that genetic removal of CSL in breast tumor cells caused accelerated growth of xenografted tumors. Loss of CSL unleashed a hypoxic response during normoxic conditions, manifested by stabilization of the HIF1α protein and acquisition of a polyploid giant-cell, cancer stem cell-like, phenotype. At the transcriptome level, loss of CSL upregulated more than 1,750 genes and less than 3% of those genes were part of the Notch transcriptional signature. Collectively, this suggests that CSL exerts functions beyond serving as the central node in the Notch signaling cascade and reveals a role for CSL in tumorigenesis and regulation of the cellular hypoxic response.

•

Loss of CSL accelerates tumor growth

•

CSL deficiency unleashes a hypoxic response during normoxia

•

Loss of CSL leads to a polyploid giant-cell, cancer stem cell-like morphology

•

CSL-deficient cells show a Notch-independent transcriptional signature

Human pluripotent stem cell culture density modulates YAP signaling

Human pluripotent stem cell (hPSC) density is an important factor in self-renewal and differentiation fates; however, the mechanisms through which hPSCs sense cell density and process this information in making cell fate decisions remain to be fully understood. One particular pathway that may prove important in density-dependent signaling in hPSCs is the Hippo pathway, which is regulated by cell-cell contact and mechanosensing through the cytoskeleton and has been linked to the maintenance of stem cell pluripotency. To probe regulation of Hippo pathway activity in hPSCs, we assessed whether Hippo pathway transcriptional activator YAP was differentially modulated by cell density. At higher cell densities, YAP phosphorylation and localization to the cytoplasm increased, which led to decreased YAP-mediated transcriptional activity. Furthermore, total YAP protein levels diminished at high cell density due to the phosphorylation-targeted degradation of YAP. Inducible shRNA knockdown of YAP reduced expression of YAP target genes and pluripotency genes. Finally, the density-dependent increase of neuroepithelial cell differentiation was mitigated by shRNA knockdown of YAP. Our results suggest a pivotal role of YAP in cell density-mediated fate decisions in hPSCs.

Expression of microRNA-106b and its clinical significance in cutaneous melanoma

MicroRNA-106b (miR-106b) is overexpressed in various types of cancers and is associated with the regulation of carcinogenic processes. However, its clinical significance in cutaneous melanoma has not been reported. qRT-PCR was performed to examine the expression of miR-106b in 15 cases of dysplastic nevi, 17 cases of melanoma metastases, and 97 cases of primary cutaneous melanoma tissue samples. Survival rate was determined with Kaplan-Meier and statistically analyzed with the log-rank method between groups. Survival data were evaluated through multivariate Cox regression analysis. Significant differences in miR-106b expression were shown between dysplastic nevi and primary cutaneous melanomas (P < 0.01), between primary melanomas and metastatic cutaneous melanomas (P < 0.01), and between primary cutaneous melanomas and metastatic cutaneous melanomas (P < 0.001). We found that high miR-106b expression was correlated with Breslow thickness (P = 0.002), tumor ulceration (P = 0.002), and advanced clinical stage (P < 0.001). The patients with high miR-106b expression showed shorter 5-year overall survival than those with low miR-106b expression (P = 0.02; log-rank test). Multivariate regression analysis showed that the status of miR-106b expression was an independent prognostic factor for overall survival (HR = 2.09, 95%CI: 1.11-10.26, P = 0.02). This study showed that miR-106b may contribute to the progression of cutaneous melanoma and its up-regulation may be independently associated with poor prognosis of cutaneous melanoma. This suggests that miR-106b might serve as a promising biological marker for further risk stratification in the management of cutaneous melanoma.

Efficient differentiation of human pluripotent stem cells to endothelial progenitors via small-molecule activation of WNT signaling

Human pluripotent stem cell (hPSC)-derived endothelial cells and their progenitors may provide the means for vascularization of tissue-engineered constructs and can serve as models to study vascular development and disease. Here, we report a method to efficiently produce endothelial cells from hPSCs via GSK3 inhibition and culture in defined media to direct hPSC differentiation to CD34⁺CD31⁺ endothelial progenitors. Exogenous vascular endothelial growth factor (VEGF) treatment was dispensable, and endothelial progenitor differentiation was β-catenin dependent. Furthermore, by clonal analysis, we showed that CD34⁺CD31⁺CD117⁺TIE-2⁺ endothelial progenitors were multipotent, capable of differentiating into calponin-expressing smooth muscle cells and CD31⁺CD144⁺vWF⁺I-CAM1⁺ endothelial cells. These endothelial cells were capable of 20 population doublings, formed tube-like structures, imported acetylated low-density lipoprotein, and maintained a dynamic barrier function. This study provides a rapid and efficient method for production of hPSC-derived endothelial progenitors and endothelial cells and identifies WNT/β-catenin signaling as a primary regulator for generating vascular cells from hPSCs.

•

WNT pathway activation directs hPSC differentiation to endothelial progenitors

•

hPSC-derived endothelial progenitors can differentiate to endothelial cells

•

Purified hPSC-derived endothelial cells are capable of 20 population doublings

•

WNT pathway activation permits defined production of endothelial cells from hPSCs

Next-generation models of human cardiogenesis via genome editing

Cardiogenesis is one of the earliest and most important steps during human development and is orchestrated by discrete families of heart progenitors, which build distinct regions of the fetal heart. For the past decade, a lineage map for the distinct subsets of progenitors that generate the embryonic mammalian heart has begun to lay a foundation for the development of new strategies for rebuilding the adult heart after injury, an unmet clinical need for the vast majority of patients with end-stage heart failure who are not heart transplant recipients. The studies also have implications for the root causes of congenital heart disease, which affects 1 in 50 live births, the most prevalent malformations in children. Although much of this insight has been generated in murine models, it is becoming increasingly clear that there can be important divergence with principles and pathways for human cardiogenesis, as well as for regenerative pathways. The development of human stem cell models, coupled with recent advances in genome editing with RNA-guided endonucleases, offers a new approach for the primary study of human cardiogenesis. In addition, application of the technology to the in vivo setting in large animal models, including nonhuman primates, has opened the door to genome-edited large animal models of adult and congenital heart disease, as well as a detailed mechanistic dissection of the more diverse and complex set of progenitor families and pathways, which guide human cardiogenesis. Implications of this new technology for a new generation of human-based, genetically tractable systems are discussed, along with potential therapeutic applications.

Temporal impact of substrate mechanics on differentiation of human embryonic stem cells to cardiomyocytes

A significant clinical need exists to differentiate human pluripotent stem cells (hPSCs) into cardiomyocytes, enabling tissue modeling for in vitro discovery of new drugs or cell-based therapies for heart repair in vivo. Chemical and mechanical microenvironmental factors are known to impact the efficiency of stem cell differentiation, but cardiac differentiation protocols in hPSCs are typically performed on rigid tissue culture polystyrene (TCPS) surfaces, which do not present a physiological mechanical setting. To investigate the temporal effects of mechanics on cardiac differentiation, we cultured human embryonic stem cells (hESCs) and their derivatives on polyacrylamide hydrogel substrates with a physiologically relevant range of stiffnesses. In directed differentiation and embryoid body culture systems, differentiation of hESCs to cardiac troponin T-expressing (cTnT+) cardiomyocytes peaked on hydrogels of intermediate stiffness. Brachyury expression also peaked on intermediate stiffness hydrogels at day 1 of directed differentiation, suggesting that stiffness impacted the initial differentiation trajectory of hESCs to mesendoderm. To investigate the impact of substrate mechanics during cardiac specification of mesodermal progenitors, we initiated directed cardiomyocyte differentiation on TCPS and transferred cells to hydrogels at the Nkx2.5/Isl1+ cardiac progenitor cell stage. No differences in cardiomyocyte purity with stiffness were observed on day 15. These experiments indicate that differentiation of hESCs is sensitive to substrate mechanics at early stages of mesodermal induction, and proper application of substrate mechanics can increase the propensity of hESCs to differentiate to cardiomyocytes.

Insulin inhibits cardiac mesoderm, not mesendoderm, formation during cardiac differentiation of human pluripotent stem cells and modulation of canonical Wnt signaling can rescue this inhibition

The study of the regulatory signaling hierarchies of human heart development is limited by a lack of model systems that can reproduce the precise developmental events that occur during human embryogenesis. The advent of human pluripotent stem cell (hPSC) technology and robust cardiac differentiation methods affords a unique opportunity to monitor the full course of cardiac induction in vitro. Here, we show that stage-specific activation of insulin signaling strongly inhibited cardiac differentiation during a monolayer-based differentiation protocol that used transforming growth factor β superfamily ligands to generate cardiomyocytes. However, insulin did not repress cardiomyocyte differentiation in a defined protocol that used small molecule regulators of canonical Wnt signaling. By examining the context of insulin inhibition of cardiomyocyte differentiation, we determined that the inhibitory effects by insulin required Wnt/β-catenin signaling and that the cardiomyocyte differentiation defect resulting from insulin exposure was rescued by inhibition of Wnt/β-catenin during the cardiac mesoderm (Nkx2.5+) stage. Thus, insulin and Wnt/β-catenin signaling pathways, as a network, coordinate to influence hPSC differentiation to cardiomyocytes, with the Wnt/β-catenin pathway dominant to the insulin pathway. Our study contributes to the understanding of the regulatory hierarchies of human cardiomyocyte differentiation and has implications for modeling human heart development.

A small molecule inhibitor of SRC family kinases promotes simple epithelial differentiation of human pluripotent stem cells

Human pluripotent stem cells (hPSCs) provide unprecedented opportunities to study the earliest stages of human development in vitro and have the potential to provide unlimited new sources of cells for regenerative medicine. Although previous studies have reported cytokeratin 14+/p63+ keratinocyte generation from hPSCs, the multipotent progenitors of epithelial lineages have not been described and the developmental pathways regulating epithelial commitment remain largely unknown. Here we report membrane localization of β-catenin during retinoic acid (RA)--induced epithelial differentiation. In addition hPSC treatment with the Src family kinase inhibitor SU6656 modulated β-catenin localization and produced an enriched population of simple epithelial cells under defined culture conditions. SU6656 strongly upregulated expression of cytokeratins 18 and 8 (K18/K8), which are expressed in simple epithelial cells, while repressing expression of the pluripotency gene Oct4. This homogeneous population of K18+K8+Oct4- simple epithelial precursor cells can further differentiate into cells expressing keratinocyte or corneal-specific markers. These enriched hPSC-derived simple epithelial cells may provide a ready source for development and toxicology cell models and may serve as a progenitor for epithelial cell transplantation applications.

Full-term pregnant women have higher lumbar epidural pressure than non-pregnant women: a preliminary report

The objective of this study was to compare the lumbar epidural pressure of full-term pregnant women with that of non-pregnant women. The epidural pressure of 20 full-term pregnant women and 15 non-pregnant women was measured during epidural needle insertion in the lateral position (T0), and at 30-s intervals following insertion (T1-T3), after the patient was turned supine (T4-T6), and after local anaesthetic injection (T7-T9). Results showed that the average epidural pressures following epidural insertion in the lateral position (average of T1-T3), in the supine position (average of T4-T6), and after local anaesthetic injection (average of T7-T9) were all significantly higher in the pregnant women compared with those who were not pregnant (p= 0.0293, 0.0109 and 0.0309, respectively). Epidural pressures increased significantly after women were turned supine (p < 0.001). Average epidural pressures were positive for all time points, T0-T9. It was concluded that the epidural pressure in the pregnant women was higher than in those who were not pregnant, both in the lateral and the supine position.

Directed cardiomyocyte differentiation from human pluripotent stem cells by modulating Wnt/β-catenin signaling under fully defined conditions

The protocol described here efficiently directs human pluripotent stem cells (hPSCs) to functional cardiomyocytes in a completely defined, growth factor- and serum-free system by temporal modulation of regulators of canonical Wnt signaling. Appropriate temporal application of a glycogen synthase kinase 3 (GSK3) inhibitor combined with the expression of β-catenin shRNA or a chemical Wnt inhibitor is sufficient to produce a high yield (0.8-1.3 million cardiomyocytes per cm(2)) of virtually pure (80-98%) functional cardiomyocytes in 14 d from multiple hPSC lines without cell sorting or selection. Qualitative (immunostaining) and quantitative (flow cytometry) characterization of differentiated cells is described to assess the expression of cardiac transcription factors and myofilament proteins. Flow cytometry of BrdU incorporation or Ki67 expression in conjunction with cardiac sarcomere myosin protein expression can be used to determine the proliferative capacity of hPSC-derived cardiomyocytes. Functional human cardiomyocytes differentiated via these protocols may constitute a potential cell source for heart disease modeling, drug screening and cell-based therapeutic applications.