Identification and Characterization of a LIF-STAT3/Activin-Smad2/3 Dual Responsive Pluripotent Stem Cell State

The medical and bioindustrial applications of pluripotent stem cells rely on our understanding of their biology. Pluripotent stem cell lines derived from embryos in different stages depend on distinct signalling pathways. Embryonic stem cells (ESCs), derived from the inner cell mass (ICM) of preimplantation embryos, are dependent on LIF/STAT3 signalling, while epiblast stem cells (EpiSCs), established from the postimplantation embryos, require Activin A/Smad2/3 signalling. Recent studies revealed the presence of intermediate pluripotent stem cell populations. Their growth factor responsiveness, gene expression pattern and associated chromatic signatures, are compatible with the state intermediate between ESCs and EpiSCs. However, it remains unknown whether such cell populations represent a stable clonally intermediate cell state. In this thesis, I describe the discovery and characterization of novel stem cell lines displaying gene expression pattern intermediate between ESCs and EpiSCs. These cells respond to LIF/STAT3 as well as Activin/Smad2/3 signalling at single cell level. They can integrate into the ICM and generate chimeric embryos. In keeping with a more advanced differentiation stage than that of ESCs, the LIF/Activin dual responsive stem cells showed accelerated temporal gene expression kinetics during in vitro differentiation in embryo bodies. I found that these properties are shared by some induced pluripotent stem cell (iPSC) lines. The notion of an intermediate state was consolidated by a genome-wide microarray profiling. The hierarchical clustering analysis grouped LIF/Activin dual responsive stem cells together into a cluster intermediate between ESCs and EpiSCs. These findings advanced our understanding of the regulation of pluripotency. A better understanding of distinct differentiation state of pluripotent stem cells and their signalling responsiveness is crucial for developing tailored strategies for lineage/cell type differentiation

Metallic foreign body deep in the prevertebral space after an endomyocardial biopsy: a case report

INTRODUCTION: Although inspirated or ingested foreign bodies constitute a common otolaryngologic emergency, the removal of a solitary retained foreign body from the neck has seldom been described in the literature. The ingestion of foreign bodies commonly results in perforated viscose or extraluminal migration to adjacent structures quite a long period of time after the fact. To the best of our knowledge, this is the first English language description of an endomyocardial biopsy complicated by a retained foreign body deep in the prevertebral space of the patient’s neck. We report such a case and share our experience in treating it. CASE PRESENTATION: A 68-year-old Asian man suffering right-sided heart failure underwent an endomyocardial biopsy via his right internal jugular vein. After undergoing the procedure, he was found to have retained a metallic cup tip which had become lodged in his neck. A surgeon then performed neck exploration and the foreign body was removed without adverse effect. CONCLUSIONS: Decision making as to whether to remove the foreign body or not remains controversial. However, the later incidence of adhesive fibrosis or, even worse, of a catastrophic abscess or adjacent vascular injury might occur if the foreign body was not removed. Early exploration is suggested, if the patient’s condition makes this feasible

Spontaneous Escherichia coli Meningitis Associated with Hemophagocytic Lymphohistiocytosis

Spontaneous Escherichia coli meningitis has not been previously reported in association with hemophago-cytic lymphohistiocytosis (HLH). A previously healthy 72-year-old woman was admitted due to fever, nuchal rigidity, disturbed consciousness and splenomegaly. Anemia, thrombocytopenia and hyperfer-ritinemia developed on the 8th day of hospitalization. Cultures of cerebrospinal fluid and blood grew E. coli. Abundant macrophages overwhelmed erythrocytes in the bone marrow aspirate, confirming the presence of hemophagocytosis. E. coli meningitis was managed with a 40-day course of antibiotic treatment. However, the severity of anemia and thrombocytopenia progressed despite intensive transfusion therapy. The patient died of HLH on the 60th day of hospitalization

Back-end of line compatible transistors for hybrid CMOS applications

The low-temperature back-end of line (BEOL) compatible transparent amorphous oxide semiconductor (TAOS) TFTs and poly-Si TFTs are the suitable platforms for three-dimensional (3D) integration hybrid CMOS technologies. The n-channel amorphous indium tungsten oxide (a-IWO) ultra-thin-film transistors (UTFTs) have been successfully fabricated and demonstrated in the category of indium oxide based thin film transistors (TFTs). We have scaled down thickness of a-IWO channel to 4nm. The proposed a-IWO UTFTs with low operation voltages exhibit good electrical characteristics: near ideal subthreshold swing (S.S.) ~ 63mV/dec., high field-effect mobility (FE) ~ 25.3 cm2/V-s. In addition, we also have fabricated the novel less metal contamination Ni-induced lateral crystallization (LC-NILC) p-channel poly-Si TFTs. The matched electrical characteristics of n-channel and p-channel devices with low operation voltage and low IOFF are exhibiting the promising candidate for future hybrid CMOS applications

Measurement of Deformity at the Craniovertebral Junction: Correlation of Triangular Area and Myelopathy

Objective Diseases of the craniovertebral junction (CVJ) are commonly associated with deformity, malalignment, and subsequent myelopathy. The misaligned CVJ might cause compression of neuronal tissues and subsequently clinical symptoms. The triangular area (TA), measured by magnetic resonance imaging/images (MRI/s), is a novel measurement for quantification of the severity of compression to the brain stem. This study aimed to assess the normal and pathological values of TA by a comparison of patients with CVJ disease to age- and sex-matched controls. Moreover, postoperative TAs were correlated with outcomes. Methods Consecutive patients who underwent surgery for CVJ disease were included for comparison to an age- and sex-matched cohort of normal CVJ persons as controls. The demographics, perioperative information, and pre- and postoperative 2-year cervical MRIs were collected for analysis. Cervical TAs were measured and compared. Results A total of 201 patients, all of whom had pre- or postoperative MRI, were analyzed. The TA of the CVJ deformity group was larger than the healthy control group (1.62 ± 0.57 cm2 vs. 1.01 ± 0.18 cm2, p < 0.001). Moreover, patients who had combined anterior odontoidectomy and posterior laminectomy with fixation had the greatest reduction in the TA (1.18 ± 0.58 cm2). Conclusion In CVJ deformity, the measurement of the cervical TA could indicate the severity of brain stem compression. After surgery, the TA had a varying degree of improvement, which could represent the efficacy of surgery

Low glomerular filtration rate and risk of stroke: meta-analysis

Objective To qualitatively and quantitatively investigate the link between a low estimated glomerular filtration rate (eGFR) at baseline and risk of future stroke