Fabrication of Hydrogen Boride Thin Film by Ion Exchange in MgB2

In this study, hydrogen boride films are fabricated by ion-exchange treatment on magnesium diboride (MgB₂) films under ambient temperature and pressure. We prepared oriented MgB₂ films on strontium titanate (SrTiO₃) substrates using pulsed laser deposition (PLD). Subsequently, these films were treated with ion exchangers in acetonitrile solution. TOF-SIMS analysis evidenced that hydrogen species were introduced into the MgB₂ films by using two types of ion exchangers: proton exchange resin and formic acid. According to the HAXPES analysis, negatively charged boron species were preserved in the films after the ion-exchange treatment. In addition, the FT-IR analysis suggested that B-H bonds were formed in the MgB₂ films following the ion-exchange treatment. The ion-exchange treatment using formic acid was more efficient compared to the resin treatment; with respect to the amount of hydrogen species introduced into the MgB₂ films. These ion-exchanged films exhibited photoinduced hydrogen release as observed in a powder sample. Based on the present study, we expect to be able to control the morphology and hydrogen content of hydrogen boride thin films by optimising the ion-exchange treatment process, which will be useful for further studies and device applications.

CDK1 dependent phosphorylation of hTERT contributes to cancer progression

The telomerase reverse transcriptase is upregulated in the majority of human cancers and contributes directly to cell transformation. Here we report that hTERT is phosphorylated at threonine 249 during mitosis by the serine/threonine kinase CDK1. Clinicopathological analyses reveal that phosphorylation of hTERT at threonine 249 occurs more frequently in aggressive cancers. Using CRISPR/Cas9 genome editing, we introduce substitution mutations at threonine 249 in the endogenous hTERT locus and find that phosphorylation of threonine 249 is necessary for hTERT-mediated RNA dependent RNA polymerase (RdRP) activity but dispensable for reverse transcriptase and terminal transferase activities. Cap Analysis of Gene Expression (CAGE) demonstrates that hTERT phosphorylation at 249 regulates the expression of specific genes that are necessary for cancer cell proliferation and tumor formation. These observations indicate that phosphorylation at threonine 249 regulates hTERT RdRP and contributes to cancer progression in a telomere independent manner.

Regulated telomerase reverse transcriptase (hTERT) activity is common in human tumors. Here, the authors show that hTERT is phosphorylated by CDK1 and that this event is necessary for hTERT-mediated RNA dependent RNA polymerase activity but not for reverse transcriptase and terminal transferase activities.

The NF-κB regulator IκBβ exhibits different molecular interactivity and phosphorylation status from IκBα in an IKK2-catalysed reaction

Activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) transcription factor, a central player in immune response regulation, is based on phosphorylation of inhibitor of kappaB alpha (IκBα) by the Inhibitor of kappaB kinase (IKK) that triggers IκBα degradation. Although inhibitor of kappaB beta (IκBβ) is structurally similar to IκBα, its precise characteristics remain undefined. Herein, we report that the molecular interactivity of IκBβ with the kinase-active region of IKK subunit 2 (IKK2), as well as its phosphorylation status, differs markedly from those of IκBα. A mass spectrometry analysis revealed that IκBβ phosphorylation sites are distributed in its C-terminal region, whereas IκBα phosphorylation sites are located in the N-terminal region. Furthermore, IKK2 phosphorylation sites in IκBβ are found in a region distinct from typical degradation signals, such as phosphodegron and proline/glutamic acid/serine/threonine-rich sequence (PEST) motifs. Mutation of the IκBβ phosphorylation sites enhances its resistance to homeostatic proteasomal degradation. These findings contribute a novel concept in NF-κB/IKK signalling research.

P6531Evidence-practice gap in the preprocedural risk assessment for contrast-induced acute kidney injury

Background

Contrast-induced acute kidney injury (CI-AKI) is one of the frequently encountered and costly complications after percutaneous coronary intervention (PCI). Clinical practice guidelines strongly recommend that PCI patients should universally undergo preprocedural assessment for the risk of CI-AKI, and the contrast volume (CV) should be minimized to an achievable level, particularly among the high AKI risk patients. However, data on the CV use based on the comprehensive preprocedural risk assessment is still lacking.

Purpose

Our study aimed to 1) assess the impact of CV increase with the incidence of AKI among high AKI risk patients, and 2) retrospectively evaluate the used CV based on the preprocedural comprehensive risk assessment for patients undergoing PCI within multicenter longitudinal registry.

Methods

Between 2009 and 2018, 22,373 patients underwent PCI in 14 participating facilities, and consecutive patient data was registered. AKI was defined as a >0.3mg/dl absolute or >1.5-fold relative increase in post-PCI creatinine or new initiation of dialysis, based on the Acute Kidney Injury Network criteria. The post-procedural creatinine was defined as the highest value within 30 days after the indexed procedure. Congruent with the National Cardiovascular Data Registry (NCDR) definition, if more than 1 post-procedural creatinine level was measured, the highest value was used for determining AKI. We divided the patients into four groups according to quartile of NCDR AKI risk scores.

Results

Mean age of the patients were 68.7±11.1 years, and 79.1% were male. Mean CV use was 161.4±74.8ml. The incidence of CI-AKI was 8.9%, and was particularly high among high AKI risk patients (21.1%); CV (per 1ml linear increase) was directly associated with the occurrence of AKI (OR: 1.002 per unit in CV; 95% CI: 1.001–1.003; P<0.001) in these patients. CV during PCI decreased with the progression of chronic kidney disease (CKD), but it did not alter by the overall NCDR AKI risk score (Figure). After multivariable adjustment, CV was predicted by stage of CKD (−13.68ml; 95% CI: −12.05 to −15.30ml; P<0.001), but not by the value of pre-procedure prediction score (NCDR AKI risk score, P=0.575).

CV according to CKD/NCDR AKI risk score

Conclusions

Higher CV was directly associated with the occurrence of AKI among higher AKI risk patients. However, CV use was largely influenced by the stage of renal disease, and not with overall patient risk presented by contemporary risk scores. Our results have identified an important evidence-practice gap and emphasizes the importance of total preprocedural assessment to minimize CV and prevent subsequent AKI.

Acknowledgement/Funding

KAKENHI (16KK0186, 16H05215, 25460630, 25460777), Bayer, Daiichi Sankyo, Bristol-Myers Squibb, Teikoku Seiyaku, Sumitomo Dainippon, AstraZeneka, Pfizer

Parallel homodimer structures of the extracellular domains of the voltage-gated sodium channel β4 subunit explain its role in cell-cell adhesion

Voltage-gated sodium channels (VGSCs) are transmembrane proteins required for the generation of action potentials in excitable cells and essential for propagating electrical impulses along nerve cells. VGSCs are complexes of a pore-forming α subunit and auxiliary β subunits, designated as β1/β1B-β4 (encoded by SCN1B-4B, respectively), which also function in cell-cell adhesion. We previously reported the structural basis for the trans homophilic interaction of the β4 subunit, which contributes to its adhesive function. Here, using crystallographic and biochemical analyses, we show that the β4 extracellular domains directly interact with each other in a parallel manner that involves an intermolecular disulfide bond between the unpaired Cys residues (Cys⁵⁸) in the loop connecting strands B and C and intermolecular hydrophobic and hydrogen-bonding interactions of the N-terminal segments (Ser³⁰-Val³⁵). Under reducing conditions, an N-terminally deleted β4 mutant exhibited decreased cell adhesion compared with the wild type, indicating that the β4 cis dimer contributes to the trans homophilic interaction of β4 in cell-cell adhesion. Furthermore, this mutant exhibited increased association with the α subunit, indicating that the cis dimerization of β4 affects α-β4 complex formation. These observations provide the structural basis for the parallel dimer formation of β4 in VGSCs and reveal its mechanism in cell-cell adhesion.

Dissociated Agonist of Glucocorticoid Receptor or Prednisone for Active Rheumatoid Arthritis: Effects on P1NP and Osteocalcin Pharmacodynamics

Fosdagrocorat (PF‐04171327), a dissociated agonist of the glucocorticoid receptor, has potent anti‐inflammatory activity in patients with rheumatoid arthritis with reduced adverse effects on bone health. To identify fosdagrocorat doses with bone formation marker changes similar to prednisone 5 mg, we characterized treatment‐related changes in amino‐terminal propeptide of type I collagen (P1NP) and osteocalcin (OC) with fosdagrocorat (1, 5, 10, or 15 mg) and prednisone (5 or 10 mg) in a phase II randomized trial (N = 323). The time course of markers utilized a mixed‐effects longitudinal kinetic‐pharmacodynamic model. Median predicted changes from baseline at week 8 with fosdagrocorat 5, 10, and 15 mg were −18, −22, and −22% (P1NP), and −7, −13, and −17% (OC), respectively. Changes with prednisone 5 and 10 mg were −15% and −18% (P1NP) and −10% and −17% (OC). The probability of fosdagrocorat doses up to 15 mg being noninferior to prednisone 5 mg for P1NP and OC changes was >90%.

Simple microfluidic formation of highly heterogeneous microfibers using a combination of sheath units

This paper presents the formation of complex cross-sectional microfibers using three-dimensional microfluidic devices. The compartments and shapes of core and shell layers in the microfibers were independently controlled via three-dimensional fluidic channels fabricated by the combination of sheath units. The number of layers is easily expanded by the stacking of these units. Therefore, the highly heterogeneous microfibers of alginate hydrogel are obtained in polydimethylsiloxane structures. This widely expandable method has great potential for the development of functional and complex fiber-shaped materials.

A high-resolution passive droplet-phase sample sorter using multi-stage droplet transfer

A fully passive volume-dependent droplet sorter using repeated and multiple on-rail transfer of microdroplets in a cascade channel is presented in this research.

Structure-based site-directed photo-crosslinking analyses of multimeric cell-adhesive interactions of voltage-gated sodium channel β subunits

The β1, β2, and β4 subunits of voltage-gated sodium channels reportedly function as cell adhesion molecules. The present crystallographic analysis of the β4 extracellular domain revealed an antiparallel arrangement of the β4 molecules in the crystal lattice. The interface between the two antiparallel β4 molecules is asymmetric, and results in a multimeric assembly. Structure-based mutagenesis and site-directed photo-crosslinking analyses of the β4-mediated cell-cell adhesion revealed that the interface between the antiparallel β4 molecules corresponds to that in the trans homophilic interaction for the multimeric assembly of β4 in cell-cell adhesion. This trans interaction mode is also employed in the β1-mediated cell-cell adhesion. Moreover, the β1 gene mutations associated with generalized epilepsy with febrile seizures plus (GEFS+) impaired the β1-mediated cell-cell adhesion, which should underlie the GEFS+ pathogenesis. Thus, the structural basis for the β-subunit-mediated cell-cell adhesion has been established.

Increased undercarboxylated osteocalcin/intact osteocalcin ratio in patients undergoing hemodialysis

Serum undercarboxylated osteocalcin (ucOC)/intact osteocalcin (iOC) ratio increased >1.0 in the patients undergoing hemodialysis, particularly in those with high bone turnover state. Consequently, serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in hemodialysis patients.

INTRODUCTION

Serum intact osteocalcin (iOC), undercarboxylated OC (ucOC), and the ucOC/iOC ratio are considered clinically relevant indices in pre-dialysis chronic kidney disease (CKD) and hemodialysis (HD) patients, despite their accumulation in uremic serum.

METHODS

Serum iOC and ucOC were measured along with serum intact parathyroid hormone (iPTH), bone alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase (TRACP)-5b in 89 pre-dialysis CKD and 189 HD patients.

RESULTS

Serum iOC and ucOC showed significantly negative correlations with estimated glomerular filtration rate in pre-dialysis CKD patients, although serum ucOC/iOC ratio did not correlate. Serum ucOC was significantly greater in HD patients than in pre-dialysis CKD patients, while serum iOC did not differ significantly, resulting in serum ucOC/iOC ratio >1.0 in 135 (71.4%) out of 189 HD patients. HD patients with high serum ucOC/iOC ratio (>1.0) had a significantly younger age and significantly higher values of body mass index, serum creatinine, albumin, phosphate, iPTH, and TRACP-5b than those with low ucOC/iOC ratio (≤ 1.0). The baseline iPTH and P1NP correlated with the changes of the ucOC/iOC ratio during the 2 days of the inter-dialytic period. Multivariate analysis showed that log [ucOC/iOC] in HD patients was significantly associated with log [iPTH], log [BAP], or log [TRACP-5b].

CONCLUSIONS

Serum ucOC/iOC ratio >1.0 was observed in as high as 71.4% of HD patients, preferentially with high bone turnover state, in comparison with pre-dialysis CKD patients. These data suggested that serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in HD patients.

Increased active PTH(1-84) fraction as a predictor of poor mortality in male hemodialysis patients

We reported previously that serum parathyroid hormone [PTH(1-84)]/intact PTH[PTH(1-84) + PTH(7-84)] ratio provides the better marker for parathyroid function and bone turnover state than serum PTH level itself. The present study demonstrated that higher PTH(1-84)/intact PTH ratio, but not serum PTH(1-84) and intact PTH, predicted higher all-cause mortality in 177 male hemodialysis patients.

INTRODUCTION

We reported that PTH(1-84)/intact PTH ratio provides a clinically relevant marker for parathyroid function and the resultant bone turnover state. The purpose of our study was to investigate the association of PTH(1-84)/intact PTH ratio with all-cause mortality (ACM) in male hemodialysis patients.

METHODS

The study was performed for 70 months. Serum PTH in 177 male hemodialysis patients was measured with PTH(1-84)-specific whole PTH assay and intact PTH assay which cross-reacts with N-truncated PTH including PTH(7-84).

RESULTS

The patients (n = 177) were divided into higher and lower halves based on serum levels of PTH(1-84)/intact PTH ratio (cutoff value, 0.484), intact PTH (143.8 pg/mL), and PTH(1-84) (64.1 pg/mL). In Kaplan-Meier analysis, the higher group in whole PTH/intact PTH ratio had significantly higher ACM than the lower group (P = 0.020 by log-rank test), in contrast with the insignificant difference between the higher and lower groups in intact PTH and PTH(1-84). Multivariate Cox regression hazard analysis identified higher log [PTH(1-84)/intact PTH ratio], but not log intact PTH or log PTH(1-84) as a significant independent predictor [hazard ratio 14.428 (95% CI 2.486-83.728)] for ACM after adjustment for various factors including age, hemodialysis duration, presence/absence of diabetes mellitus, BMI, log C-reactive protein, serum albumin, calcium, and phosphate. The association existed between log [PTH(1-84)/intact PTH ratio] and ACM in those without vitamin D administration (n = 95).

CONCLUSION

Higher PTH(1-84)/intact PTH ratio, which provides a relevant marker for parathyroid function, may be a significant predictor of ACM in male hemodialysis patients.

Significant inverse relationship between serum undercarboxylated osteocalcin and glycemic control in maintenance hemodialysis patients

SUMMARY

Increased levels of serum undercarboxylated osteocalcin, which were associated with bone metabolism markers, correlated inversely with indices of glucose metabolism (plasma glucose, hemoglobin A1C, and glycated albumin) in hemodialysis patients with abnormalities of bone metabolism.

INTRODUCTION

Undercarboxylated osteocalcin (ucOC), a possible marker of bone metabolism and one of the osteoblast-specific secreted proteins, has recently been reported to be associated with glucose metabolism. We tested the hypothesis that ucOC levels are associated with indices of glucose metabolism in chronic hemodialysis patients with abnormalities of bone metabolism.

METHODS

Serum ucOC, bone alkaline phosphatase (BAP, a bone formation marker), and tartrate-resistant acid phosphatase-5b (TRACP-5b, a bone resorption marker) were measured in 189 maintenance hemodialysis patients (96 diabetics and 93 non-diabetics), and their relationships with glucose metabolism were examined.

RESULTS

ucOC correlated positively with BAP (ρ = 0.489, p < 0.0001), TRACP-5b (ρ = 0.585, p < 0.0001) and intact parathyroid hormone (iPTH; ρ = 0.621, p < 0.0001). Serum ucOC levels in the diabetic patients were lower than those of non-diabetic patients (p < 0.001), although there were no significant differences in serum BAP or TRACP-5b between diabetic and non-diabetic patients. Serum ucOC correlated negatively with plasma glucose (ρ = -0.303, p < 0.0001), hemoglobin A1C (ρ = -0.214, p < 0.01), and glycated albumin (ρ = -0.271, p < 0.001), although serum BAP or TRACP-5b did not. In multiple linear regression analysis, log [plasma glucose], log [hemoglobin A1C], and log [glycated albumin] were associated significantly with log [ucOC] after adjustment for age, gender, hemodialysis duration, and body mass index but were not associated with log [BAP], log [TRACP-5b], or log [intact PTH].

CONCLUSION

Increased levels of serum ucOC, which were associated with bone metabolism markers, were inversely associated with indices of glucose metabolism in hemodialysis patients.

Serum adiponectin and bone mineral density in male hemodialysis patients

SUMMARY

Bone mineral density of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin. There was a significant positive correlation between serum adiponectin and serum NTX. Thus, adiponectin may play a role in mineral and bone disorder in chronic kidney disease stage 5 dialysis (CKD 5D) patients.

INTRODUCTION

Serum adiponectin, an adipocyte-produced hormone, has been reported to correlate negatively with bone mineral density (BMD) in the general population. However, little is known about the association between adiponectin and BMD in patients with CKD.

METHODS

BMD of the 1/3 distal and ultra-distal radius, which are enriched with cortical and cancellous bone, respectively, and the lumbar spine was measured by dual X-ray absorptiometry in 114 Japanese male hemodialysis patients (age 61.0 ± 11.1 years; hemodialysis duration 6.6 ± 3.0 years; 43.9% diabetics). Serum total adiponectin, bone formation marker (bone alkaline phosphatase, BAP), and bone resorption marker (cross-linked N-telopeptide of type I collagen (NTX)) were measured.

RESULTS

The BMD of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin level (r = -0.229, p = 0.014; r = -0.286, p = 0.002; r = -0.227, p = 0.013, respectively). In multiple linear regression analyses, serum adiponectin was significantly and independently associated with the BMD of the 1/3 distal radius (R(2) = 0.173, p < 0.001) and ultra-distal radius (R(2) = 0.278, p < 0.001) after adjustment of age, hemodialysis duration, body weight, %fat mass, and log [intact PTH], although it was not with the BMD of the lumbar spine. There was a significant positive correlation between serum adiponectin and serum NTX (r = 0.321, p < 0.001), although there was no significant correlation between serum adiponectin and serum BAP.

CONCLUSION

Increased levels of serum adiponectin were associated with decrease in BMD in male hemodialysis patients. Adiponectin may play a role in mineral and bone disorder, possibly in bone resorption, of patients with CKD 5D.

Reduction of whole PTH/intact PTH ratio as a predictor of bone metabolism in cinacalcet treatment of hemodialysis patients with secondary hyperparathyroidism

In cinacalcet treatment of hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT), not only intact parathyroid hormone (I-PTH), whole PTH (W-PTH), and bone markers, but also W-PTH/I-PTH ratio as proportion of active PTH(1-84) molecules were decreased. Changes in W-PTH/I-PTH ratio significantly correlated and predicted changes in bone marker.

INTRODUCTION

Cinacalcet partly suppresses the secretion of PTH by enhancing PTH(1-84) degradation into N-truncated fragments. The objectives of this study is to investigate the significance of the N-truncated PTH/PTH(1-84) ratio for the prediction of the effect of cinacalcet in HD patients.

METHODS

Serum parameters were measured during 12 weeks of oral cinacalcet administration at 25 mg daily in 39 HD patients with SHPT.

RESULTS

Serum Ca, Pi, W-PTH, I-PTH, and W-PTH/I-PTH ratio all decreased significantly in a time-dependent manner during cinacalcet administration. Serum tartrate-resistant acid phosphatase (TRAP) 5b reflected these changes more precisely than serum N-telopeptide of type-I collagen. At 1 week, changes in I-PTH and W-PTH correlated significantly with those in serum Pi, but not Ca. Changes in serum Pi (but not Ca) and serum W-PTH also correlated significantly with changes in serum TRAP5b at both 4 and 12 weeks, while changes in serum I-PTH correlated significantly with those in serum TRAP5b only at 12 weeks. Changes in the serum W-PTH/I-PTH ratio correlated significantly with those in serum TRAP5b at both 4 and 12 weeks, and changes in serum W-PTH/I-PTH ratio at 4 weeks showed a tendency for a correlation with changes in serum TRAP5b at 12 weeks. HD patients with a reduced W-PTH/I-PTH ratio after 4 weeks had a significantly greater reduction of TRAP5b over 12 weeks.

CONCLUSION

W-PTH and the W-PTH/I-PTH ratio allow estimation of the potency of cinacalcet in enhancement of PTH degradation, and thus no less reliable markers than I-PTH for reflecting cinacalcet-induced bone resorption.

Efficacy and safety of pregabalin for treating neuropathic pain associated with diabetic peripheral neuropathy: a 14 week, randomized, double-blind, placebo-controlled trial

AIMS

To evaluate the efficacy, safety and pharmacokinetics of pregabalin in treating neuropathic pain associated with diabetic peripheral neuropathy in Japanese patients.

METHODS

A randomized, double-blind, placebo-controlled, multicentre 14 week clinical trial was conducted. Japanese patients with diabetic peripheral neuropathy (n = 317) were randomized to receive placebo or pregabalin at 300 or 600 mg/day. The primary efficacy measure was a change of mean pain score from baseline to end-point from patients' daily pain diaries.

RESULTS

Significant reductions in pain were observed in patients treated with pregabalin at 300 and 600 mg/day vs. placebo (P < 0.05). Improvements in weekly pain scores were observed as early as week 1 and were sustained throughout the study period (300 and 600 mg/day difference from placebo at study end-point, -0.63 and -0.74, respectively). Pregabalin produced significant improvements in weekly sleep interference scores, the short-form McGill Pain Questionnaire, the Medical Outcomes Study-Sleep Scale, the 36-item Short-Form Health Survey scale, and the Patient and Clinical Global Impression of Change. Patient impressions of numbness, pain and paraesthesia were also significantly improved. Regarding treatment responders, 29.1 and 35.6% of patients treated with 300 and 600 mg/day, respectively, reported ≥ 50% improvement in mean pain scores (vs. 21.5% for placebo). Pregabalin was well tolerated; somnolence (26%), dizziness (24%), peripheral oedema (13%) and weight gain (11%) were the most common adverse events and generally were reported as mild to moderate.

CONCLUSIONS

Pregabalin was effective in reducing pain and improving sleep disturbances due to pain, and was well tolerated in Japanese patients with painful DPN.

Broad, ectopic expression of the sperm protein PLCZ1 induces parthenogenesis and ovarian tumours in mice

Mammalian metaphase II (mII) exit and embryogenesis are induced at fertilisation by a signal thought to come from the sperm protein, phospholipase C-zeta (PLCZ1). Meiotic progression can also be triggered without sperm, as in parthenogenesis, although the classic mouse in vivo parthenogenetic model, LT/Sv, fails in meiosis I owing to an unknown molecular etiology. Here, we dissect PLCZ1 specificity and function in vivo and address its ability to interfere with maternal meiotic exit. Wild-type mouse Plcz1 expression was restricted to post-pubertal testes and the brains of both sexes, with region-specifying elements mapping to a 4.1 kb Plcz1 promoter fragment. When broad ectopic PLCZ1 expression was forced in independent transgenic lines, they initially appeared healthy. Their oocytes underwent unperturbed meiotic maturation to mII but subsequently exhibited autonomous intracellular free calcium oscillations, second polar body extrusion, pronucleus formation and parthenogenetic development. Transfer of transgenic cumulus cell nuclei into wild-type oocytes induced activation and development, demonstrating a direct effect of PLCZ1 analogous to fertilisation. Whereas Plcz1 transgenic males remained largely asymptomatic, females developed abdominal swellings caused by benign ovarian teratomas that were under-represented for paternally- and placentally-expressed transcripts. Plcz1 was not overexpressed in the ovaries of LT/Sv or in human germline ovarian tumours. The narrow spectrum of PLCZ1 activity indicates that it is modulated by tissue-restricted accessory factors. This work characterises a novel model in which parthenogenesis and tumourigenesis follow full meiotic maturation and are linked to fertilisation by PLCZ1.

Epigenetic discrimination by mouse metaphase II oocytes mediates asymmetric chromatin remodeling independently of meiotic exit

In mammalian fertilization, paternal chromatin is exhaustively remodeled, yet the maternal contribution to this process is unknown. To address this, we prevented the induction of meiotic exit by spermatozoa and examined sperm chromatin remodeling in metaphase II (mII) oocytes. Methylation of paternal H3-K4 and H3-K9 remained low, unlike maternal H3, although paternal H3-K4 methylation increased in zygotes. Thus, mII cytoplasm can sustain epigenetic asymmetry in a cell-cycle dependent manner. Paternal genomic DNA underwent oocyte-mediated cytosine demethylation and acquired maternally-derived K12-acetylated H4 (AcH4-K12) independently of microtubule assembly and maternal chromatin. AcH4-K12 persisted without typical maturation-associated deacetylation, irrespective of paternal pan-genomic cytosine methylation. Contrastingly, somatic cell nuclei underwent rapid H4 deacetylation; sperm and somatic chromatin exhibited asymmetric AcH4-K12 dynamics simultaneously within the same mII oocyte. Inhibition of somatic histone deacetylation revealed endogenous histone acetyl transferase activity. Oocytes thus specify the histone acetylation status of given nuclei by differentially targeting histone deacetylase and acetyl transferase activities. Asymmetric H4 acetylation during and immediately after fertilization was dispensable for development when both parental chromatin sets were hyperacetylated. These studies delineate non-zygotic chromatin remodeling and suggest a powerful model with which to study de novo genomic reprogramming.

Injection of Mammalian Metaphase II Oocytes with Short Interfering RNAs to Dissect Meiotic and Early Mitotic Events1

The manipulation of mammalian metaphase II (mII) oocytes has illuminated the mechanisms of fertilization and early embryogenesis and is central to nuclear transfer. Although RNA interference (RNAi) would greatly facilitate this type of manipulation, its application to mature, developmentally competent mII oocytes has not been evaluated. We report efficient RNAi by the injection of short interfering RNAs (siRNAs) into mII oocytes. The levels of the target mRNA and corresponding protein were rapidly and efficiently reduced. The siRNAs were effective when injected in the subnanomolar to nanomolar range and induced concurrently RNAi of multiple targets, revealing the kinetic parameters of RNAi in mII oocytes. Coinjection of sperm with siRNA functionally abolished the transcripts in the resultant blastocysts and in cloned embryos into which siRNA was coinjected during somatic cell nuclear transfer. The RNAi method was used to dissect the early mitotic roles of meiotic regulators, which suggests that CDC20 is essential for the first mitotic division, while EMI1 and EMI2 are not essential for this process. Our results show that siRNA injection of oocytes confers temporal control of RNAi in the analysis and manipulation of key processes in mammalian meiosis and early embryogenesis.

[Metastatic lung tumor from uterine leiomyosarcoma]

We herein present 2 cases of metastatic lung tumor derived from uterine leiomyosarcoma. In the case 1, a 59-year-old woman was admitted to our hospital to examine abnormal shadow detected on chest X-ray. She had undergone hysterectomy and oophorectomy for uterine leiomyosarcoma 19 months previously. A round 3 cm mass in the right lung (S10) was seen on chest X-ray and computed tomography (CT). No other distant metastases or local recurrence were found, and the right lower lobectomy was perfomed under the clinical diagnosis of metastatic lung tumor. Postoperative pathologic examination revealed the tumor as a metastatic leiomyosarcoma. The patient recovered uneventfully, and there have been no signs of recurrence for 26 months after the pulmonary resection. In the case 2, a 58-year-old woman, who had undergone hysterectomy and oophorectomy for uterine leiomyosarcoma 7 months previously, was admitted to our hospital for further examination of pulmonary tumors on chest X-ray. Two tumors were recognized in the left lung (S8 and S10) on chest X-ray and CT. No other distant metastases or local recurrence were found, and the left lower lobectomy was performed under the clinical diagnosis of metastatic lung tumors. Pathological examinations revealed smooth muscle cells with nuclear pleomorphism and high mitotic indices. The tumors proved to be lung metastases derived from uterine leiomyosarcoma. Postoperative course was uneventful. However, brain metastasis was found 1 month after the pulmonary resection, and she underwent resection of brain metastasis. Two months after the brain metastasectomy, local recurrence of the brain tumor developed and re-resection followed by stereotactic radiotherapy was performed. Furthermore, intrapelvic recurrence was found 4 months after the pulmonary resection. Exploratory laparotomy revealed the tumor was unresectable, and she received 4 courses of chemotherapy (paclitaxel and carboplatin). For metastatic lung tumor from uterine leiomyosarcoma, surgery has been considered the best choice. However, for patients with uterine leiomyosarcoma who cannot be treated surgically because of multiple metastatic tumors or poor surgical risk chemotherapy (paclitaxel and carboplatin) or stereotactic radiotherapy can be strategies.

[Small peripheral lung cancer incidentally detected by massive hemoptysis]

A 47-year-old man was admitted to our hospital for treatment of massive hemoptysis. He was intubated and underwent bronchial arterial embolization because of this deteriorating respiratory state and uncontrollable hemoptysis. Computed tomography (CT) of the chest showed a 1-cm nodular shadow in the peripheral apical lobe (S1) of the right lung. He underwent right upper lobectomy for the purpose of preventing re-hemorrhage as well as making the definitive diagnosis of nodular shadow in S1 of the right lung. Intraoperative pathological examination revealed the nodule as adenocarcinoma, and mediastinal lymphadenectomy was added to the right upper lobectomy. The patient recovered uneventfully, and there has been no sign of recurrence for 15 months after the operation.

Mammalian Emi2 mediates cytostatic arrest and transduces the signal for meiotic exit via Cdc20

Fertilizable mammalian oocytes are arrested at the second meiotic metaphase (mII) by the cyclinB-Cdc2 heterodimer, maturation promoting factor (MPF). MPF is stabilized via the activity of an unidentified cytostatic factor (CSF), thereby suspending meiotic progression until fertilization. We here present evidence that a conserved 71 kDa mammalian orthologue of Xenopus XErp1/Emi2, which we term endogenous meiotic inhibitor 2 (Emi2) is an essential CSF component. Depletion in situ of Emi2 by RNA interference elicited precocious meiotic exit in maturing mouse oocytes. Reduction of Emi2 released mature mII oocytes from cytostatic arrest, frequently inducing cytodegeneration. Mos levels autonomously declined to undetectable levels in mII oocytes. Recombinant Emi2 reduced the propensity of mII oocytes to exit meiosis in response to activating stimuli. Emi2 and Cdc20 proteins mutually interact and Cdc20 ablation negated the ability of Emi2 removal to induce metaphase release. Consistent with this, Cdc20 removal prevented parthenogenetic or sperm-induced meiotic exit. These studies show in intact oocytes that the interaction of Emi2 with Cdc20 links activating stimuli to meiotic resumption at fertilization and during parthenogenesis in mammals.

IL-18 gene polymorphism confers susceptibility to the development of anti-GAD65 antibody in Graves' disease

AIMS

This study aimed to investigate whether interleukin-18 (IL-18) gene polymorphisms are associated with the development of antibody against the 65-kDa isoform of recombinant human glutamic acid decarboxylase (GAD65Ab) in patients with Graves' disease.

METHODS

A total of 398 unrelated Japanese patients with Graves' disease, with and without GAD65Ab, were recruited. Three single nucleotide polymorphisms in the IL-18 gene were examined and the polymorphic allele and the genotype and haplotype frequencies calculated.

RESULTS

The frequency of the GG genotype at position -4675 of the IL-18 gene was significantly lower in Graves' disease patients with GAD65Ab than those without (4% vs. 24%, P = 0.0126). The -4675C allele frequency was significantly greater in patients with GAD65Ab than those without (69% vs. 53%, P = 0.0168). The homozygous -4675G/-607A/-137G haplotype was less common in Graves' disease patients with GAD65Ab than those without (4% vs. 23%, P = 0.0144).

CONCLUSIONS

These findings in a Japanese population indicate that Graves' disease patients carrying the GG genotype at position -4657 of the promoter of the IL-18 gene or a gene in linkage disequilibrium with the -4675G/-607A/-137G haplotype have a low risk for the development of GAD65Ab in Graves' disease.

Intracellular inclusions containing mutant alpha1-antitrypsin Z are propagated in the absence of autophagic activity

Mutant alpha(1)-antitrypsin Z (alpha(1)-ATZ) protein, which has a tendency to form aggregated polymers as it accumulates within the endoplasmic reticulum of the liver cells, is associated with the development of chronic liver injury and hepatocellular carcinoma in hereditary alpha(1)-antitrypsin (alpha(1)-AT) deficiency. Previous studies have suggested that efficient intracellular degradation of alpha(1)-ATZ is correlated with protection from liver disease in alpha(1)-AT deficiency and that the ubiquitin-proteasome system accounts for a major route, but not the sole route, of alpha(1)-ATZ disposal. Yet another intracellular degradation system, autophagy, has also been implicated in the pathophysiology of alpha(1)-AT deficiency. To provide genetic evidence for autophagy-mediated disposal of alpha(1)-ATZ, here we used cell lines deleted for the Atg5 gene that is necessary for initiation of autophagy. In the absence of autophagy, the degradation of alpha(1)-ATZ was retarded, and the characteristic cellular inclusions of alpha(1)-ATZ accumulated. In wild-type cells, colocalization of the autophagosomal membrane marker GFP-LC3 and alpha(1)-ATZ was observed, and this colocalization was enhanced when clearance of autophagosomes was prevented by inhibiting fusion between autophagosome and lysosome. By using a transgenic mouse with liver-specific inducible expression of alpha(1)-ATZ mated to the GFP-LC3 mouse, we also found that expression of alpha(1)-ATZ in the liver in vivo is sufficient to induce autophagy. These data provide definitive evidence that autophagy can participate in the quality control/degradative pathway for alpha(1)-ATZ and suggest that autophagic degradation plays a fundamental role in preventing toxic accumulation of alpha(1)-ATZ.

Acute flank pain, an unusual first symptom of a spinal arteriovenous malformation

This case report describes a 46-year-old man whose first symptom was an attack of acute flank pain, followed by the gradual onset neurological symptoms. We demonstrated a small nidus and serpentine signal-void area in the spinal cord by MRI and diagnosed a glomus type of spinal arteriovenous malformation (AVM). Flank pain is a rare initial finding in an adult with spinal AVM. In cases with acute flank pain, neurologists should consider spinal AVM as a differential diagnosis.

Association between catechol-O-methyltransferase gene polymorphisms and wearing-off and dyskinesia in Parkinson's disease

Catechol-O-methyltransferase (COMT) is an enzyme that inactivates catecholamines, including levodopa. An amino acid change (Val-108-Met) in the COMT protein has been found to result in a change from high to low enzyme activity. In the present study, we genotyped 121 Japanese patients with Parkinson's disease (PD) and 100 controls. Comparison of the allele frequencies revealed that homozygosity for the low-activity allele was significantly more common among PD patients than the controls (p = 0.047, odds ratio = 3.23). In addition, homozygosity for the low-activity allele was overrepresented in PD patients that exhibited the 'wearing-off' phenomenon (p = 0.045, odds ratio = 3.82) or dyskinesia (p = 0.030, odds ratio = 4.80) compared with controls, although these differences were not significant after Bonferroni's correction. Our results may help understand the mechanism that cause complications of levodopa therapy in PD patients.

CSF hypocretin levels in Guillain-Barre syndrome and other inflammatory neuropathies

CSF hypocretin-1 was measured in 28 Guillain-Barré syndrome (GBS), 12 Miller-Fisher syndrome, 12 chronic inflammatory demyelinating polyneuropathy (CIDP), and 48 control subjects. Seven GBS subjects had undetectably low hypocretin-1 levels (<100 pg/mL). Hypocretin-1 levels were moderately reduced in an additional 11 GBS, 5 Miller-Fisher syndrome, and 1 CIDP subject. Low levels in GBS occurred early in the disease and were associated with upper CNS level abnormalities.

Progressive supranuclear palsy presenting with primary progressive aphasia--clinicopathological report of an autopsy case

We report a Japanese autopsy case of progressive supranuclear palsy (PSP). The male patient was 74 years old at the time of death. At age 64, he developed non-fluent aphasia that progressed slowly over 8 years, eventually associated with behavioral abnormality, postural instability, and dysphagia at 2 years prior to his death. Magnetic resonance imaging of the brain at age 73 demonstrated marked atrophy of the frontal lobes, particularly on the left side. Neuropathological examination revealed the typical pathology of PSP: loss of neurons, gliosis, occurrence of neurofibrillary tangles, oligodendroglial coiled bodies, and tuft-shaped astrocytes in the frontal cortex, associated with argyrophilic threads in the underlying white matter, in the basal ganglia, including the thalamus, globus pallidus, and subthalamic nucleus, and in the brainstem nuclei, including the substantia nigra, pontine nucleus, and inferior olivary nucleus. No astrocytic plaques or ballooned neurons were observed. Protein analysis revealed accumulation of hyperphosphorylated tau of 68 and 64 kDa consisting of the four repeat tau isoforms. We conclude that the present case represented PSP with an 8-year history of primary progressive aphasia (PPA). Although focal cortical symptoms in PSP are rare or absent, we should keep in mind the possibility of atypical PSP in which cortical pathology is predominant, particularly in the frontal lobe, and could result in PPA.