Ferric citrate and apo-transferrin enable erythroblast maturation with β-globin from hemogenic endothelium

Red blood cell (RBC) generation from human pluripotent stem cells (PSCs) offers potential for innovative cell therapy in regenerative medicine as well as developmental studies. Ex vivo erythropoiesis from PSCs is currently limited by the low efficiency of functional RBCs with β-globin expression in culture systems. During induction of β-globin expression, the absence of a physiological microenvironment, such as a bone marrow niche, may impair cell maturation and lineage specification. Here, we describe a simple and reproducible culture system that can be used to generate erythroblasts with β-globin expression. We prepared a two-dimensional defined culture with ferric citrate treatment based on definitive hemogenic endothelium (HE). Floating erythroblasts derived from HE cells were primarily CD45+CD71+CD235a+ cells, and their number increased remarkably upon Fe treatment. Upon maturation, the erythroblasts cultured in the presence of ferric citrate showed high transcriptional levels of β-globin and enrichment of genes associated with heme synthesis and cell cycle regulation, indicating functionality. The rapid maturation of these erythroblasts into RBCs was observed when injected in vivo, suggesting the development of RBCs that were ready to grow. Hence, induction of β-globin expression may be explained by the effects of ferric citrate that promote cell maturation by binding with soluble transferrin and entering the cells.Taken together, upon treatment with Fe, erythroblasts showed advanced maturity with a high transcription of β-globin. These findings can help devise a stable protocol for the generation of clinically applicable RBCs.

Comparing the efficacy of different methods of faecal microbiota transplantation via oral capsule, oesophagogastroduodenoscopy, colonoscopy, or gastric tube

BACKGROUND

The increasing prevalence of multidrug-resistant organism (MDRO) carriage poses major challenges to medicine as healthcare costs increase. Recently, faecal microbiota transplantation (FMT) has been discussed as a novel and effective method for decolonizing MDRO.

AIM

To compare the efficacy of different FMT methods to optimize the success rate of decolonization in patients with MDRO carriage.

METHODS

This prospective cohort study enrolled patients with MDRO carriages from 2018 to 2021. Patients underwent FMT via one of the following methods: oral capsule, oesophagogastroduodenoscopy (EGD), colonoscopy, or gastric tube.

FINDINGS

A total of 57 patients underwent FMT for MDRO decolonization. The colonoscopy group required the shortest time for decolonization, whereas the EGD group required the longest (24.9 vs 190.4 days, P = 0.022). The decolonization rate in the oral capsule group was comparable to that in the EGD group (84.6% vs 85.7%, P = 0.730). An important clinical factor associated with decolonization failure was antibiotic use after FMT (odds ratio = 6.810, P = 0.008). All four groups showed reduced proportions of MDRO species in microbiome analysis after FMT.

CONCLUSION

Compared to other conventional methods, the oral capsule is an effective FMT method for patients who can tolerate an oral diet. The discontinuation of antibiotics after FMT is a key factor in the success of decolonization.

Maintenance of Hypoimmunogenic Features via Regulation of Endogenous Antigen Processing and Presentation Machinery

Universally acceptable donor cells have been developed to address the unmet need for immunotypically matched materials for regenerative medicine. Since forced expression of hypoimmunogenic genes represses the immune response, we established universal pluripotent stem cells (PSCs) by replacing endogenous β2-microglobulin (β2m) with β2m directly conjugated to human leukocyte antigen (HLA)-G, thereby simultaneously suppressing HLA-I expression and the natural killer (NK) cell-mediated immune response. These modified human PSCs retained their pluripotency and differentiation capacity; however, surface presentation of HLA-G was absent from subsequently differentiated cells, particularly cells of neural lineages, due to the downregulation of antigen processing and presentation machinery (APM) genes. Induction of APM genes by overexpression of NLR-family CARD domain-containing 5 (NLRC5) or activator subunit of nuclear factor kappa B (NF-κB) heterodimer (RelA) recovered the surface expression of HLA-G and the hypoimmunogenicity of neural cells. Our findings enhance the utility of hypoimmunogenic cells as universal donors and will contribute to the development of off-the-shelf stem-cell therapeutics.

Generation of induced pluripotent stem cell line (KRIBBi004-A) from adult bone marrow CD34+ cells from a patient carrying 46,XX,t(1;5)(p31.1;35.1) karyotype

Induced pluripotent stem cell (iPS) technology may be advantageous for the study of genetic aberrations in terms of recapitulating the full manifestation of pathological features in vitro, identifying underlying pathways, and developing personalized therapeutics rather than procuring somatic cells from patients. Here, we derived an iPSC line from a patient with reciprocal chromosome translocation, t(1;5)(p31.1;35.1), as a novel alternative model to identify clinical phenotypes induced by genetic instability. The resulting iPSC line generated from somatic cells with an existing instability showed representative characteristics of PSCs, and might serve as an unparalleled cellular resource for the development of a custom remedy.

Human Blood Vessel Organoids Penetrate Human Cerebral Organoids and Form a Vessel-Like System

Vascularization of tissues, organoids and organ-on-chip models has been attempted using endothelial cells. However, the cultured endothelial cells lack the capacity to interact with other somatic cell types, which is distinct from developing vascular cells in vivo. Recently, it was demonstrated that blood vessel organoids (BVOs) recreate the structure and functions of developing human blood vessels. However, the tissue-specific adaptability of BVOs had not been assessed in somatic tissues. Herein, we investigated whether BVOs infiltrate human cerebral organoids and form a blood-brain barrier. As a result, vascular cells arising from BVOs penetrated the cerebral organoids and developed a vessel-like architecture composed of CD31⁺ endothelial tubes coated with SMA⁺ or PDGFR⁺ mural cells. Molecular markers of the blood-brain barrier were detected in the vascularized cerebral organoids. We revealed that BVOs can form neural-specific blood-vessel networks that can be maintained for over 50 days.

Wogonin Influences Osteosarcoma Stem Cell Stemness Through ROS-dependent Signaling

Backgorund/Aim: Wogonin, a flavonoid-like compound extracted from the root of Scutellaria baicalensis Georgi, has been shown to have anticancer effects against cancer cells. Osteosarcoma is the most malignant type of bone cancer and can appear in any bone, with a high propensity for relapse and metastasis. The present study aimed to assess the anticancer effects of wogonin on osteosarcoma stem cells.

MATERIALS AND METHODS

The cytotoxic effects of wogonin on CD133⁺ Cal72 osteosarcoma stem cells were assessed through in vitro experiments by MTT assay, transwell assay, sphere-formation assay, flow cytometry, immunocytochemistry and western blotting.

RESULTS

Wogonin suppressed stem cell characteristics and the expression of stem cell-related genes by regulating reactive oxygen species (ROS) levels and ROS-related signaling of CD133⁺ Cal72 cells, effects which were reversed by ROS scavenger N-acetylcysteine.

CONCLUSION

Wogonin may be a promising candidate for successful clinical management of osteosarcoma by regulating ROS-related mechanisms and stem cell-related genes.

Establishment of iPSC (KRIBBi001-A) from CD34+ group O D-negative bone marrow blood

Human induced pluripotent stem cells with indefinite propagation in vitro provide a potential donor source of cells including erythroid cells for human therapy. Since group O D-negative (RhD^-) blood cells are considered as universal donors for transfusion, it is compelling to derive iPSC line from group O/RhD^- sample as a new cellular source to generate universal RBCs. The resulting iPSC line derived from group O/RhD^- somatic source showed typical features of pluripotent stem cells and could provide an unprecedented cellular tool to develop universal therapeutics for blood transfusion.

BRM270 targets cancer stem cells and augments chemo-sensitivity in cancer

Over the past decade, a number of studies have demonstrated the resistance of cancer cells to conventional drugs and have recognized this as a major challenge in cancer therapy. While attempting to understand the underlying mechanisms of chemoresistance, several studies have suggested that the presence of cancer stem cells (CSCs) in tumors is one of the major pathways contributing toward resistance. Chemoresistance leads to cancer treatment failure and worsens the prognosis of patients. Natural herbal compounds are gaining attention as an alternative treatment strategy for cancer. These compounds may be effective against chemoresistant cells either alone or synergistically alongside conventional drugs, sensitizing cancer cells and enhancing the therapeutic efficacy. BRM270 is a natural compound made from seven herbal plant (Saururus chinensis, Citrus unshiu Markovich, Aloe vera, Arnebia euchroma, Portulaca oleracea, Prunella vulgaris var. lilacina and Scutellaria bacicalensis) extracts used in Asian traditional medicine and has the potential to target CSCs. Several studies have demonstrated the positive effects of BRM270 against chemoresistant cancer and its synergy alongside existing cancer drugs, including paclitaxel and gefitinib. These effects have been observed against various cancer types, including resistant non-small cell lung cancer (NSCLC), glioblastoma, multi-drug resistant osteosarcoma, cervical cancer, pancreatic cancer and hepatocarcinoma. The present review discusses the effects of BRM270 treatment against CSC-associated chemoresistance in common types of cancer.

Specific Chicken Egg Yolk Antibody Improves the Protective Response against Gallibacterium anatis Infection

Gallibacterium anatis is a pathogen associated with peritonitis and salpingitis in chickens and other avian species. Novel safety prevention strategies are urgently needed because of widespread multidrug resistance and antigenic diversity. The objective of this study was to produce a specific chicken egg yolk antibody and evaluate its protective response against a G. anatis infection model in 4-week-old chicks. Enzyme-linked immunosorbent assays showed that hens immunized with the recombinant N terminus of Gallibacterium toxin A (GtxA-N) had significantly increased antibody titers against GtxA-N in serum and egg yolk IgY. Western blotting showed that IgY antibody had specificity against GtxA-N in the egg yolks of immunized hens. The growth of G. anatis in brain heart infusion (BHI) broth and agar was significantly inhibited by the GtxA-N-specific IgY antibody. The protective effects of the specific IgY antibody were evaluated in G. anatis-infected chicks after intramuscular injection (10 mg/ml). The anti-GtxA-N antibody titers in the sera of G. anatis-challenged chicks following an injection of specific IgY antibody were significantly higher than those of the control and the nonspecific IgY groups, but lower lesion scores for the peritoneum, liver, and duodenum were found after specific IgY antibody treatment. The results from this study suggest that the GtxA-N-specific IgY antibody could potentially improve the protective response against G. anatis infection in chicks.

Synthesis and evaluation of the antiproliferative efficacy of BRM270 phytocomposite nanoparticles against human hepatoma cancer cell lines

BRM270 is the most leading phytochemical extract that possesses potent anticancer properties. A major challenge associated with this drug is its low bioavailability and thus requires high dosages for cancer treatment. Here, we report the novel nano-synthesis of phyto-composite, BRM270 for the first time by mechanical milling method with specific modifications for enhanced cytotoxicity against HepG2 human hepatoma cancer cells. Unlike free BRM270 and other phytomedicines, BRM270 nanoparticles (BRM270 NPs) are well-dispersed and small sized (23 to 70 nm) which is believed to greatly enhanced cellular uptake. Furthermore, the acidic tumor microenvironment attracts BRM270 NPs enhancing targeted therapy while leaving normal cells less affected. The comparative cytotoxicity analysis using MTT assay among the three treatment groups, such as free BRM270, BRM270 NPs, and doxorubicin demonstrated that BRM270 NPs induced greater cytotoxicity against HepG2 cells with an effective drug concentration of 12 μg/ml. From FACS analysis, we observed an apoptotic cell death of 44.4% at BRM270 NPs treated cells while only 12.5% found in the free BRM270 treated cells. Further, the comparative relative expression profiling of the candidate genes were showed significant (p < 0.05) down-regulation of IL6, BCL2, p53, and MMP9 in the BRM270 NPs treated cells, compared to the free BRM270 and doxorubicin. Indeed, the genes, CASPASE 9 and BAX have shown significant (p < 0.05) upregulation in cells treated with BRM270 NPs as compared to counter treatment groups. The investigation of the signal pathways and protein-protein network associations were also carried out to elucidate the functional insights underlying anti-cancer potential of BRM270 NPs in HepG2 cells. Taken together, our findings demonstrated that these uniquely engineered BRM270 NPs effectively enter into the cancer cells due to its acidic microenvironment thereby inducing apoptosis and regulate the cell-proliferation in-vitro at extremely low dosages.

Effectiveness of antibacterial prophylaxis with non-absorbable polymyxin B compared to levofloxacin after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Fluoroquinolones are widely used for antibacterial prophylaxis during neutropenia following hematopoietic stem cell transplantation (HSCT). Nevertheless, data are inadequate as to whether fluoroquinolones decrease mortality rate compared with other antibiotics.

METHODS

We retrospectively compared the efficacy of antibacterial prophylaxis using non-absorbable polymyxin B (PB) (n = 106) or systemic levofloxacin (LVFX) (n = 140) after allogeneic SCT at our institute between 2004 and 2013.

RESULTS

No significant difference was observed between the 2 groups in the cumulative incidences of failure of prophylaxis (P = 0.21), clinically documented infections (P = 0.70), or non-relapse mortality within the first 100 days after transplantation (P = 0.42). With bacteremia, the rate of resistance to LVFX was 82% in the PB group and 100% in the LVFX group (P = 0.41). Also, no significant difference was found in overall survival between the 2 groups (P = 0.78).

CONCLUSION

Our results indicate no difference in the effectiveness of antibacterial prophylaxis between systemic antibiotic LVFX and non-absorbable antibiotic PB.

Association between polymorphisms in period genes and bone density in postmenopausal Korean women

OBJECTIVE

In the present study, we aimed to investigate the association between genetic polymorphisms in period (PER) genes and bone mineral density (BMD) in postmenopausal Korean women.

METHODS

The PER1 c.2247C> T and c.2884C> G polymorphisms; the PER2 c.661G> A and c.3731G> A polymorphisms; the PER3 c.2592G> A, c.3029C> T, c.3035C> T, and c.3083T> C polymorphisms, and the 54 bp variable number tandem repeats polymorphism were analyzed in 551 postmenopausal Korean women. Serum leptin, soluble leptin receptor, osteoprotegerin, soluble receptor activator of the nuclear factor-κB ligand, and bone markers including bone alkaline phosphatase and carboxy-terminal telopeptide of type I collagen were measured, and the lumbar spine and femoral neck BMDs were also determined.

RESULTS

The PER2 c.661G> A, PER3 c.3029C> T and c.3035C> T polymorphisms were not observed. The PER2 and PER3 polymorphisms evaluated were not related to BMD, whereas associations of the c.2247C> T and c.2884C> G polymorphisms in PER1 with the lumbar spine BMD were observed both singly and in combination. The CC haplotype homozygotes showed significantly lower lumbar spine BMD than participants with other genotypes. Additionally, 2.01-fold higher odds for osteoporosis of the lumbar spine were found in the CC haplotype homozygotes compared to women not carrying the haplotype CC allele. No significant differences in bone markers were detected according to the PER1 haplotype genotype.

CONCLUSIONS

Our results suggest that both the PER1 c.2247C> T and c.2884C> G polymorphisms may be genetic factors affecting the lumbar spine BMD in postmenopausal Korean women.

Mitochondrial swelling and microtubule depolymerization are associated with energy depletion in axon degeneration

Although mitochondrial dysfunction is intimately related to axonal degeneration following nerve injury, the molecular mechanisms of mitochondrial swelling and its mechanistic relation to axonal degeneration are largely unknown. Previous studies have demonstrated that axonal degeneration in the injured peripheral nerves shows two morphologically distinct phases: (1) A latency period (∼24h), in which the morphology of axonal cytoskeletons seems unchanged, followed by (2) an execution period (36-48h), which shows a catastrophic granular degeneration of most axonal structures in rodent axons. In the present study, we found that, in the sciatic nerve axotomy model, energy failure and microtubule depolymerization occurred during the latency period whereas mitochondrial swelling and neurofilament degradation started in the execution period. The energy repletion with NAD or an NAD/pyruvate mixture inhibited microtubule depolymerization, mitochondrial swelling and axonal degeneration in transected sciatic nerve axons. In addition, microtubule perturbing agents enhanced axonal degeneration and mitochondrial swelling. Extracellular calcium chelation did not affect energy failure, microtubule depolymerization or mitochondrial swelling, but it did prevent neurofilament degradation. These findings suggest that an early disturbance in energy dynamics regardless of mitochondrial swelling might be a key trigger for the initiation of axonal degeneration and that extracellular calcium influx is a late effector for neurofilament degradation.

Risk factors affecting cardiac left-ventricular hypertrophy and systolic and diastolic function in the chronic phase of allogeneic hematopoietic cell transplantation

Chronic impairment of cardiac function can be an important health risk and impair the quality of life, and may even be life-threatening for long-term survivors of allogeneic hematopoietic cell transplantation (HCT). However, risk factors for and/or the underlying mechanism of cardiac dysfunction in the chronic phase of HCT are still not fully understood. We retrospectively investigated factors affecting cardiac function and left-ventricular hypertrophy (LVH) in the chronic phase of HCT. Sixty-three recipients who survived for >1 year after receiving HCT were evaluated using echocardiography. Based on simple linear regression models, high-dose TBI-based conditioning was significantly associated with a decrease in left-ventricular ejection fraction and the early peak flow velocity/atrial peak flow velocity ratio, following HCT (coefficient=-5.550, P=0.02 and coefficient=-0.268, P=0.02, respectively). These associations remained significant with the use of multiple linear regression models. Additionally, the serum ferritin (s-ferritin) level before HCT was found to be a significant risk factor for LVH on multivariable logistic analysis (P=0.03). In conclusion, our study demonstrated that a myeloablative regimen, especially one that involved high-dose TBI, impaired cardiac function, and that a high s-ferritin level might be associated with the development of LVH in the chronic phase of HCT.

Incarcerated diaphragmatic hernia as a cause of acute abdomen

Diaphragmatic hernias are usually congenital, and they usually occur in the neonatal group. They do occur in the adult population, albeit very rarely. We present a case of an adult male patient with complications as a result of a congenital diaphragmatic hernia. The patient presented with atypical abdominal pain and respiratory distress. Radiological investigations confirmed a left hydropneumothorax as well as large bowel obstruction secondary to herniation of the omentum and transverse colon through a congenital defect in the left hemi-diaphragm. He had a laparotomy, which confirmed the radiological findings and a perforated transverse colon. He went onto have an extended right hemicolectomy and end-ileostomy; his left hemithorax was lavaged and a thoracostomy tube was inserted. He recovered well, except that he developed an empyema postoperatively for which he required a thoracotomy and decortication. He made good recovery following this and was discharged home nine days following his initial laparotomy.

Fatal BK virus pneumonia following stem cell transplantation

We report the case of a 39-year-old male patient who died of severe BK virus (BKV) pneumonia 168 days after hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia. After suffering from BKV-associated late-onset hemorrhagic cystitis (HC) with long-term sustained BKV viremia, he died of rapidly progressive pneumonia. On autopsy, numerous viral intranuclear inclusions were seen in his lungs and bladder. An immunohistochemical examination of his lungs was positive for simian virus 40. Based on these pathological results and the high sustained BKV viral load in his blood, we reached a diagnosis of BKV pneumonia. Viral infection can occasionally become life threatening among HSCT recipients. It is widely known that BKV can cause late-onset HC, but BKV-associated pneumonia is rare. Because of its rapid progression and poor prognosis, it is difficult to make an antemortem diagnosis of BKV pneumonia. A treatment strategy for BKV pneumonia also needs to be formulated. Similar to other viral pathogens, BKV can cause pneumonia and the clinician should therefore be aware of it in immunocompromised patients.

Immunoglobulin prophylaxis against cytomegalovirus infection in patients at high risk of infection following allogeneic hematopoietic cell transplantation

Reports on the efficacy of intravenous immunoglobulin (IVIG) prophylaxis against cytomegalovirus (CMV) infection after allogeneic hematopoietic cell transplantation (HCT) have often sparked controversy. In addition, we are not aware of any study that has examined whether prophylaxis with IVIG affects the incidence of CMV infection in high-risk patients--those who are elderly or have received human leukocyte antigen (HLA) mismatched HCT. In the present open-label, phase II study, we addressed this question. We enrolled 106 patients in the study. The cumulative incidences of CMV infection at 100 days after HCT were similar in the intervention and the control groups (68% and 64%, P=.89; 89% and 87%, P=.79, respectively, for patients 55 years or older and those who received HLA-mismatched HCT). In those who received HLA-mismatched HCT, 1-year overall survival after HCT was 46% in the intervention group and 40% in the control group (P=.31); for age≥55 years, the corresponding values were 46% and 40% (P=.27). Our data showed that prophylaxis with regular polyvalent IVIG did not affect the incidence of CMV infections or survival among older patients or those who receive HLA-mismatched HCT.

Concurrent reactivation of latent EBV with hepatitis A can affect clinical feature of childhood hepatitis

AIMS

Some children with acute hepatitis A virus (HAV) infection have concurrent Epstein-Barr virus (EBV) reactivation serologically. We studied the frequency of EBV reactivation during HAV infection and determined whether simultaneous occurrence of EBV reactivation and HAV infection affected the clinical features of HAV infection.

METHODS

The medical records of patients under 19 years of age diagnosed with acute hepatitis A between January 1996 and June 2009 were reviewed.

RESULTS

Among 72 patients with acute hepatitis A, 22 patients (30.6%) had EBV reactivation. A markedly prolonged duration of full recovery from hepatitis was observed in reactivated group. The peak levels of AST and ALT in reactivated group were higher than non-reactivated group (p = 0.012 and p < 0.001, respectively). Higher peak levels of AST and ALT in reactivated subgroups over 10 years old were observed compared to non-reactivated subgroup (p = 0.027 and p = 0.001, respectively). Duration of recovery showed significant differences between two subgroups.

CONCLUSIONS

Concurrent reactivation of latent EBV and HAV infections is common. EBV reactivation with HAV infection adversely affects the clinical feature of hepatitis. Therefore, we should keep in mind that the concurrence especially in older children may cause worse injury to the liver.

Missing xy-band Fermi surface in 4d transition-metal oxide Sr2RhO4: effect of the octahedra rotation on the electronic structure

Electronic structures of the 4d transition-metal oxide compound Sr2RhO4 are investigated by angle-resolved photoemission spectroscopy and density-functional electronic structure calculations. In the measured Fermi surfaces (FS) of Sr2RhO4, the xy-band FS sheet expected from the well-established results of the FS of Sr2RuO4 is missing, the volume of which should be different only by one additional electron for Sr2RhO4. The apparent contradiction is resolved by a careful analysis of the band structure where the rotation of octahedra results in the hybridization of e(g) and t(2g) states and thus plays a key role in the determination of the electronic structure near EF. The modification of the FS structure due to the distorted lattice is related to the charge transfer among the orbital states and suggested to be relevant to the metal-insulator transition in Ca(2-x)Sr(x)RuO4.

Effect of the New York State cigarette fire safety standard on ignition propensity, smoke constituents, and the consumer market

OBJECTIVES

This study examines empirical evidence from the New York experience testing tobacco industry arguments made in opposition to fire safety standards for cigarettes.

DESIGN

Percentages of cigarettes exhibiting full length burns (FLBs), cigarette sales before and following the implementation of the New York standards, a sample of retail cigarette prices, brand availability, and selected smoke constituent yields were compared between cigarettes sold in New York and two other states. Cigarette paper analysis was conducted on cigarettes sold in New York.

RESULTS

New York cigarette brands averaged 10.0% FLBs as compared to 99.8% for California and Massachusetts brands. Reduced ignition propensity (RIP) appears to have been achieved by cigarette paper banding. Cigarette sales, prices, and brand availability do not appear to have been affected by the New York standards. Yields of the majority of smoke constituents tested did not differ substantially between RIP cigarettes sold in New York as compared to the same brands sold in Massachusetts. Average yields of tar, carbon monoxide, and two compounds were slightly higher, the yields of seven compounds were higher for one brand only, and nicotine was lower, among New York brands tested.

CONCLUSIONS

RIP cigarette brands have been designed to meet the New York fire safety standards. Their introduction has not affected cigarette sales or prices in New York. There is no evidence that the small increases in smoke constituent yields affect the already highly toxic nature of cigarette smoke. Data on smoking caused fires, deaths, and injuries dating from after the change in law are not yet available. Such data will be able to address the question of whether the demonstrated reduced ignition standards are associated with reduced fires and injuries. Based on the New York experience, prior industry objections to producing RIP cigarettes are unfounded. Other states and nations should adopt similar standards.

JNK pathway mediates apoptotic cell death induced by tumor suppressor LKB1 in Drosophila

Although recent progresses have unveiled the diverse in vivo functions of LKB1, detailed molecular mechanisms governing these processes still remain enigmatic. Here, we showed that Drosophila LKB1 negatively regulates organ growth by caspase-dependent apoptosis, without affecting cell size and cell cycle progression. Through genetic screening for LKB1 modifiers, we discovered the JNK pathway as a novel component of LKB1 signaling; the JNK pathway was activated by LKB1 and mediated the LKB1-dependent apoptosis. Consistently, LKB1-null mutant was defective in embryonic apoptosis and displayed a drastic hyperplasia in the central nervous system; these phenotypes were fully rescued by ectopic JNK activation as well as wild-type LKB1 expression. Furthermore, inhibition of LKB1 resulted in epithelial morphogenesis failure, which was associated with a decrease in JNK activity. Collectively, our studies unprecedentedly elucidate JNK as the downstream mediator of the LKB1-dependent apoptosis, and provide a new paradigm for understanding the diverse LKB1 functions in vivo.

Continuous tuning of electronic correlations by alkali adsorption on layered 1T-TaS2

Angle-resolved photoemission spectroscopy shows that a Mott-Hubbard type metal-insulator transition occurs at the Rb adsorbed surface of the layered charge-density-wave compound 1T-TaS2. The transition is driven by adsorption induced modifications of the charge-density wave and of the interlayer coupling, leading to an increase of the on-site Coulomb correlation energy and a narrowing of the Ta 5d band perpendicular to the layers, respectively. The continuous rearrangement of spectral weight is measured live during the deposition process.

Mechanism of gap opening in a triple-band Peierls system: in atomic wires on Si

One dimensional (1D) metals are unstable at low temperature undergoing a metal-insulator transition coupled with a periodic lattice distortion, a Peierls transition. Angle-resolved photoemission study for the 1D metallic chains of In on Si(111), featuring a metal-insulator transition and triple metallic bands, clarifies in detail how the multiple band gaps are formed at low temperature. In addition to the gap opening for a half-filled ideal 1D band with a proper Fermi surface nesting, two other quasi-1D metallic bands are found to merge into a single band, opening a unique but k-dependent energy gap through an interband charge transfer. This result introduces a novel gap-opening mechanism for a multiband Peierls system where the interband interaction is important.

Fermi surface and quasiparticle dynamics of Na0.7CoO2 investigated by angle-resolved photoemission spectroscopy

We present the first angle-resolved photoemission study of Na0.7CoO2, the host material of the superconducting NaxCoO2.nH(2)O series. Our results show a hole-type Fermi surface, a strongly renormalized quasiparticle band, a small Fermi velocity, and a large Hubbard U. The quasiparticle band crosses the Fermi level from M toward Gamma suggesting a negative sign of effective single-particle hopping t(eff) (about 10 meV) which is on the order of magnetic exchange coupling J in this system. Quasiparticles are well defined only in the T-linear resistivity (non-Fermi-liquid) regime. Unusually small single-particle hopping and unconventional quasiparticle dynamics may have implications for understanding the phase of matter realized in this new class of a strongly interacting quantum system.

Occlusal adjustment for treating and preventing temporomandibular joint disorders

To assess the effectiveness of occlusal adjustment (OA) for treating temporomandibular disorders (TMD) in adults and preventing TMD. The Cochrane Controlled Trials Register, MEDLINE and EMBASE were comprehensively searched using the Cochrane methods. Reports and review articles were retrieved. Unpublished reports or abstracts were considered from the SIGLE database. All randomized or quasi-randomized controlled trials comparing OA with placebo, reassurance or no treatment in adults with TMD. The outcomes were global measures of symptoms, pain, headache and limitation of movement. Data collection and analysis followed the Cochrane Oral Health Group's statistical guidelines. Results showed no difference between OA and control group in symptom-based outcomes for treatment or incidence of symptoms for prevention. There is no evidence that OA treats or prevents TMD. OA cannot be recommended for the management or prevention of TMD. Future trials should use standardized diagnostic criteria and outcome measures when evaluating TMD.

Electronic quasiparticle renormalization on the spin wave energy scale

High-resolution photoemission data of the (110) iron surface reveal the existence of well-defined metallic surface resonances in good correspondence to band calculations. Close to the Fermi level, their dispersion and momentum broadening display anomalies characteristic of quasiparticle renormalization due to coupling to bosonic excitations. Its energy scale exceeds that of phonons by far, and is in striking coincidence with that of the spin wave spectrum in iron. The self-energy behavior thus gives spectroscopic evidence of a quasiparticle mass enhancement due to electron-magnon coupling.