Yonsei University

About: Yonsei University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Cancer. The organization has 50162 authors who have published 106172 publications receiving 2279044 citations. The organization is also known as: Yonsei.

Drosophila Microbiome Modulates Host Developmental and Metabolic Homeostasis via Insulin Signaling

Abstract: The symbiotic microbiota profoundly affect many aspects of host physiology; however, the molecular mechanisms underlying host-microbe cross-talk are largely unknown. Here, we show that the pyrroloquinoline quinone–dependent alcohol dehydrogenase (PQQ-ADH) activity of a commensal bacterium, Acetobacter pomorum, modulates insulin/insulin-like growth factor signaling (IIS) in Drosophila to regulate host homeostatic programs controlling developmental rate, body size, energy metabolism, and intestinal stem cell activity. Germ-free animals monoassociated with PQQ-ADH mutant bacteria displayed severe deregulation of developmental and metabolic homeostasis. Importantly, these defects were reversed by enhancing host IIS or by supplementing the diet with acetic acid, the metabolic product of PQQ-ADH.

Macroscopic 10-terabit-per-square-inch arrays from block copolymers with lateral order.

Abstract: Generating laterally ordered, ultradense, macroscopic arrays of nanoscopic elements will revolutionize the microelectronic and storage industries. We used faceted surfaces of commercially available sapphire wafers to guide the self-assembly of block copolymer microdomains into oriented arrays with quasi-long-range crystalline order over arbitrarily large wafer surfaces. Ordered arrays of cylindrical microdomains 3 nanometers in diameter, with areal densities in excess of 10 terabits per square inch, were produced. The sawtoothed substrate topography provides directional guidance to the self-assembly of the block copolymer, which is tolerant of surface defects, such as dislocations. The lateral ordering and lattice orientation of the single-grain arrays of microdomains are maintained over the entire surface. The approach described is parallel, applicable to different substrates and block copolymers, and opens a versatile route toward ultrahigh-density systems.

Direct reprogramming of human neural stem cells by OCT4

Abstract: Induced pluripotent stem (iPS) cells have been generated from mouse and human somatic cells by ectopic expression of four transcription factors (OCT4 (also called POU5F1), SOX2, c-Myc and KLF4). We previously reported that Oct4 alone is sufficient to reprogram directly adult mouse neural stem cells to iPS cells. Here we report the generation of one-factor human iPS cells from human fetal neural stem cells (one-factor (1F) human NiPS cells) by ectopic expression of OCT4 alone. One-factor human NiPS cells resemble human embryonic stem cells in global gene expression profiles, epigenetic status, as well as pluripotency in vitro and in vivo. These findings demonstrate that the transcription factor OCT4 is sufficient to reprogram human neural stem cells to pluripotency. One-factor iPS cell generation will advance the field further towards understanding reprogramming and generating patient-specific pluripotent stem cells.

Signaling Pathways Downstream of Pattern-Recognition Receptors and Their Cross Talk

Abstract: Pattern-recognition receptors (PRRs) initiate innate immunity through pathogen recognition. Serum PRRs opsonize pathogens for enhanced phagocytic clearance. Toll-like receptors (TLRs) initiate common NF-κB/AP-1 and distinct IRF3/7 pathways to coordinate innate immunity and to initiate adaptive immunity against diverse pathogens. Cytoplasmic caspase-recruiting domain (CARD) helicases, such as RIG-I/MDA5, mediate antiviral immunity by inducing the production of type I interferons via the adaptor IPS-1, whereas nucleotide-binding oligomerization domain (NOD)-like receptors mediate mainly antibacterial immunity by activating NF-κB or inflammasomes. Dectin-1 is important for antifungal immunity, promoting phagocytosis and activating NF-κB. Potentially harmful TLR signaling pathways can be negatively regulated by negative feedback mechanisms and also by anti-inflammatory factors such as TGFβ, interleukin (IL)-10, and steroids. Many combinations of TLR-TLR and TLR-NOD modulate inflammatory responses. TLR...

Capecitabine and cisplatin with or without cetuximab for patients with previously untreated advanced gastric cancer (EXPAND): a randomised, open-label phase 3 trial

Abstract: Summary Background Patients with advanced gastric cancer have a poor prognosis and few efficacious treatment options. We aimed to assess the addition of cetuximab to capecitabine-cisplatin chemotherapy in patients with advanced gastric or gastro-oesophageal junction cancer. Methods In our open-label, randomised phase 3 trial (EXPAND), we enrolled adults aged 18 years or older with histologically confirmed locally advanced unresectable (M0) or metastatic (M1) adenocarcinoma of the stomach or gastro-oesophageal junction. We enrolled patients at 164 sites (teaching hospitals and clinics) in 25 countries, and randomly assigned eligible participants (1:1) to receive first-line chemotherapy with or without cetuximab. Randomisation was done with a permuted block randomisation procedure (variable block size), stratified by disease stage (M0 vs M1), previous oesophagectomy or gastrectomy (yes vs no), and previous (neo)adjuvant (radio)chemotherapy (yes vs no). Treatment consisted of 3-week cycles of twice-daily capecitabine 1000 mg/m 2 (on days 1–14) and intravenous cisplatin 80 mg/m 2 (on day 1), with or without weekly cetuximab (400 mg/m 2 initial infusion on day 1 followed by 250 mg/m 2 per week thereafter). The primary endpoint was progression-free survival (PFS), assessed by a masked independent review committee in the intention-to-treat population. We assessed safety in all patients who received at least one dose of study drug. This study is registered at EudraCT, number 2007-004219-75. Findings Between June 30, 2008, and Dec 15, 2010, we enrolled 904 patients. Median PFS for 455 patients allocated capecitabine-cisplatin plus cetuximab was 4·4 months (95% CI 4·2–5·5) compared with 5·6 months (5·1–5·7) for 449 patients who were allocated to receive capecitabine-cisplatin alone (hazard ratio 1·09, 95% CI 0·92–1·29; p=0·32). 369 (83%) of 446 patients in the chemotherapy plus cetuximab group and 337 (77%) of 436 patients in the chemotherapy group had grade 3–4 adverse events, including grade 3–4 diarrhoea, hypokalaemia, hypomagnesaemia, rash, and hand-foot syndrome. Grade 3–4 neutropenia was more common in controls than in patients who received cetuximab. Incidence of grade 3–4 skin reactions and acne-like rash was substantially higher in the cetuximab-containing regimen than in the control regimen. 239 (54%) of 446 in the cetuximab group and 194 (44%) of 436 in the control group had any grade of serious adverse event. Interpretation Addition of cetuximab to capecitabine-cisplatin provided no additional benefit to chemotherapy alone in the first-line treatment of advanced gastric cancer in our trial. Funding Merck KGaA.