KIF4 regulates neuronal morphology and seizure susceptibility via the PARP1 signaling pathway

Epilepsy is a common neurological disease worldwide, and one of its causes is genetic abnormalities. Here, we identified a point mutation in KIF4A, a member of kinesin superfamily molecular motors, in patients with neurological disorders such as epilepsy, developmental delay, and intellectual disability. KIF4 is involved in the poly (ADP-ribose) polymerase (PARP) signaling pathway, and the mutation (R728Q) strengthened its affinity with PARP1 through elongation of the KIF4 coiled-coil domain. Behavioral tests showed that KIF4-mutant mice exhibited mild developmental delay with lower seizure threshold. Further experiments revealed that the KIF4 mutation caused aberrant morphology in dendrites and spines of hippocampal pyramidal neurons through PARP1-TrkB-KCC2 pathway. Furthermore, supplementing NAD, which activates PARP1, could modulate the TrkB-KCC2 pathway and rescue the seizure susceptibility phenotype of the mutant mice. Therefore, these findings indicate that KIF4 is engaged in a fundamental mechanism regulating seizure susceptibility and could be a potential target for epilepsy treatment.

A neuropathy-associated kinesin KIF1A mutation hyper-stabilizes the motor-neck interaction during the ATPase cycle

The mechanochemical coupling of ATPase hydrolysis and conformational dynamics in kinesin motors facilitates intramolecular interaction cycles between the kinesin motor and neck domains, which are essential for microtubule-based motility. Here, we characterized a charge-inverting KIF1A-E239K mutant that we identified in a family with axonal-type Charcot-Marie-Tooth disease and also in 24 cases in human neuropathies including spastic paraplegia and hereditary sensory and autonomic neuropathy. We show that Glu239 in the β7 strand is a key residue of the motor domain that regulates the motor-neck interaction. Expression of the KIF1A-E239K mutation has decreased ability to complement Kif1a^+/- neurons, and significantly decreases ATPase activity and microtubule gliding velocity. X-ray crystallography shows that this mutation causes an excess positive charge on β7, which may electrostatically interact with a negative charge on the neck. Quantitative mass spectrometric analysis supports that the mutation hyper-stabilizes the motor-neck interaction at the late ATP hydrolysis stage. Thus, the negative charge of Glu239 dynamically regulates the kinesin motor-neck interaction, promoting release of the neck from the motor domain upon ATP hydrolysis.

Association of Daily Physical Activity with Disability in Community-Dwelling Older Adults With/Without Chronic Kidney Disease

OBJECTIVES

Physical activity is recommended for disability prevention in the older adult population; however, the level of physical activity required for older adults with chronic kidney disease (CKD) remains unknown. This study aimed to examine the associations between daily physical activity and disability incidence in older adults with and without CKD to determine relevant daily physical activity levels.

DESIGN

Prospective observational study.

SETTING AND PARTICIPANTS

3,786 community-dwelling older adults aged ≥65 years.

MEASUREMENTS

Mean daily times spent in light- (LPA) and moderate-to-vigorous physical activity (MVPA) were measured using triaxial accelerometers. CKD was defined by a creatinine estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Disability incidence was identified as long-term care insurance certification during a 60-month follow-up period. Associations between physical activity and disability incidence were examined using Cox proportional hazard models stratified by the CKD status. Non-linear and linear associations were tested using the restricted cubic spline.

RESULTS

A total of 1,054 individuals were identified to have CKD. Disability incidence was higher in the CKD group than in the non-CKD group. The adjusted cox proportional hazard models indicated that a 10-minute increase in MVPA time was associated with lower disability incidence in the non-CKD group (hazard ratio [HR], 0.838; 95% confidence interval [CI]: 0.764-0.918) and the CKD group (HR, 0.859; 95% CI: 0.766-0.960). Linear associations were observed in MVPA for the non-CKD and CKD groups.

CONCLUSION

Increasing MVPA was associated with lower disability incidence in older adults with and without CKD. These findings can help devise disability prevention strategies for older CKD patients.

Association between Non-Face-to-Face Interactions and Incident Disability in Older Adults

OBJECTIVES

This observational prospective cohort study, conducted between September 2015 and February 2019, aimed to investigate the association between the incidence of disability and non-face-to-face interactions among community-dwelling older adults in Japan.

DESIGN

Participants reported their interaction status using a self-report questionnaire. Face-to-face interactions comprised in-person meetings, while virtual interactions (e.g., via phone calls or emails) were defined as non-face-to-face interactions. We examined the relationship between their interaction status at baseline and the risk of disability incidence at follow-up. We also considered several potential confounding variables, such as demographic characteristics.

SETTING

The National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes.

PARTICIPANTS

We included 1159 adults from Takahama City aged ≥75 years (mean age ± standard deviation = 79.5 ± 3.6 years).

MEASUREMENTS

Interaction status was assessed using a self-reported questionnaire consisting of two sections (face-to-face and non-face-to-face interactions), and four questionnaire items. Based on the responses we categorized study participants into four groups: "both interactions," "face-to-face only," "non-face-to-face only," and "no interactions."

RESULTS

Individuals with both kinds of interactions (49.3/1000 person-years) or only one kind of interaction (face-to-face = 57.7/1000 person-years; non-face-to-face = 41.2 person-years) had lower incidence of disability than those with no interactions (88.9/1000 person-years). Moreover, the hazard ratios adjusted for potential confounding factors for the incidence of disability in the both interaction, face-to-face-only, and non-face-to-face only groups were 0.57 (confidence interval = 0.39-0.82; p = 0.003), 0.66 (confidence interval = 0.44-0.98; p = 0.038), and 0.47 (confidence interval = 0.22-0.99; p = 0.048), respectively.

CONCLUSION

Considering the interaction status of older adults in their day-to-day practice, clinicians may be able to achieve better outcomes in the primary prevention of disease by encouraging older adults to engage in any form of interaction, including non-face-to-face interactions.

Pregnancy outcomes in women with rheumatic diseases: a real-world observational study in Japan

OBJECTIVES

We aimed to evaluate the obstetric complications and the risk factors for these events in pregnant women with rheumatic diseases (RDs).

METHODS

A single-center retrospective study of women with RDs at Hokkaido University Hospital between 2007 and 2016 was conducted. Clinical features and maternal and fetal outcomes were retrospectively collected. The rate of pregnancy complications was compared with the general obstetric population (GOP) in Japan.

RESULTS

Overall, 132 pregnancies in 95 women with RDs were recorded. Underlying RDs were systemic erythematosus (SLE) (n = 57), antiphospholipid syndrome (APS) (n = 35), rheumatoid arthritis (n = 9), and other RDs (n = 31). Antiphospholipid antibodies (aPL) were detected in 44 pregnancies (32%). Glucocorticoid was used in 82 pregnancies (62%), and tacrolimus in 20 pregnancies (15%). There were 24 disease flares (18%), but no RD-related death was documented. We recorded 112 live births, 6 abortions, 8 miscarriages, and 6 stillbirths. Pregnancies with RDs appeared to have frequent, emergency cesarean sections and preterm deliveries compared with GOP (30% vs 15% and 21% vs 14%, respectively). The median [interquartile range] birthweight in SLE and APS was lower than GOP (2591 [2231-2958] g and 2600 [2276-2920] g vs 2950 [2650-3250] g, respectively). In pregnancies with SLE, low complement levels presented the risk of maternal complications (odds ratio [95% CI]; 3.9 [1.0-14.9], p = 0.046) and anti-DNA antibody positivity was significantly correlated with the risk of fetal complications (3.5 [1.1-11.2], p = 0.036). In pregnancies with APS, maternal age over 35 years and duration of disease longer than 9 years (7.4 [1.3-40.8], p = 0.021, and 11.16 [1.1-118.8], p = 0.046, respectively) were significantly correlated with the risk of fetal complications.

CONCLUSION

Pregnancies with RDs were at increased risk of having both maternal complications and adverse neonatal outcomes, indicating these pregnancies should be closely monitored.

Kinesin-binding-triggered conformation switching of microtubules contributes to polarized transport

Kinesin-1, the founding member of the kinesin superfamily of proteins, is known to use only a subset of microtubules for transport in living cells. This biased use of microtubules is proposed as the guidance cue for polarized transport in neurons, but the underlying mechanisms are still poorly understood. Here, we report that kinesin-1 binding changes the microtubule lattice and promotes further kinesin-1 binding. This high-affinity state requires the binding of kinesin-1 in the nucleotide-free state. Microtubules return to the initial low-affinity state by washing out the binding kinesin-1 or by the binding of non-hydrolyzable ATP analogue AMPPNP to kinesin-1. X-ray fiber diffraction, fluorescence speckle microscopy, and second-harmonic generation microscopy, as well as cryo-EM, collectively demonstrated that the binding of nucleotide-free kinesin-1 to GDP microtubules changes the conformation of the GDP microtubule to a conformation resembling the GTP microtubule.

Enhanced biomass production of duckweeds by inoculating a plant growth-promoting bacterium, Acinetobacter calcoaceticus P23, in sterile medium and non-sterile environmental waters

Duckweed offers the promise of a co-benefit culture combining water purification with biomass production. Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium isolated from a duckweed, Lemna aequinoctialis. This study quantified its growth-promoting effect on three duckweeds (L. aoukikusa, L. minor, and Spirodela polyrhiza) in sterile Hoagland solution and evaluated its usefulness in duckweed culture under non-sterile conditions. P23 promoted growth of three duckweeds in sterile Hoagland solution at low to high nutrient concentrations (1.25-10 mg NO₃-N/L and 0.25-2.0 mg PO₄-P/L). It increased the biomass production of L. aequinoctialis 3.8-4.3-fold, of L. minor 2.3-3.3-fold, and of S. polyrhiza 1.4-1.5-fold after 7 days compared with noninoculated controls. P23 also increased the biomass production of L. minor 2.4-fold in pond water and 1.7-fold in secondary effluent of a sewage treatment plant under non-sterile conditions at laboratory-scale experiments. P23 rescued L. minor from growth inhibition caused by microorganisms indigenous to the pond water. The results demonstrate that the use of P23 in duckweed culture can improve the efficiency of duckweed biomass production, and a positive effect of P23 on duckweed-based wastewater treatment can be assumed.

A novel rare variant R292H in RTN4R affects growth cone formation and possibly contributes to schizophrenia susceptibility

Reticulon 4 receptor (RTN4R) plays an essential role in regulating axonal regeneration and plasticity in the central nervous system through the activation of rho kinase, and is located within chromosome 22q11.2, a region that is known to be a hotspot for schizophrenia (SCZ) and autism spectrum disorder (ASD). Recently, rare variants such as copy-number variants and single-nucleotide variants have been a focus of research because of their large effect size associated with increased susceptibility to SCZ and ASD and the possibility of elucidating the pathophysiology of mental disorder through functional analysis of the discovered rare variants. To discover rare variants with large effect size and to evaluate their role in the etiopathophysiology of SCZ and ASD, we sequenced the RTN4R coding exons with a sample comprising 370 SCZ and 192 ASD patients, and association analysis using a large number of unrelated individuals (1716 SCZ, 382 ASD and 4009 controls). Through this mutation screening, we discovered four rare (minor allele frequency <1%) missense mutations (R68H, D259N, R292H and V363M) of RTN4R. Among these discovered rare mutations, R292H was found to be significantly associated with SCZ (P=0.048). Furthermore, in vitro functional assays showed that the R292H mutation affected the formation of growth cones. This study strengthens the evidence for association between rare variants within RTN4R and SCZ, and may shed light on the molecular mechanisms underlying the neurodevelopmental disorder.

High-resolution copy number variation analysis of schizophrenia in Japan

Recent schizophrenia (SCZ) studies have reported an increased burden of de novo copy number variants (CNVs) and identified specific high-risk CNVs, although with variable phenotype expressivity. However, the pathogenesis of SCZ has not been fully elucidated. Using array comparative genomic hybridization, we performed a high-resolution genome-wide CNV analysis on a mainly (92%) Japanese population (1699 SCZ cases and 824 controls) and identified 7066 rare CNVs, 70.0% of which were small (<100 kb). Clinically significant CNVs were significantly more frequent in cases than in controls (odds ratio=3.04, P=9.3 × 10^-9, 9.0% of cases). We confirmed a significant association of X-chromosome aneuploidies with SCZ and identified 11 de novo CNVs (e.g., MBD5 deletion) in cases. In patients with clinically significant CNVs, 41.7% had a history of congenital/developmental phenotypes, and the rate of treatment resistance was significantly higher (odds ratio=2.79, P=0.0036). We found more severe clinical manifestations in patients with two clinically significant CNVs. Gene set analysis replicated previous findings (e.g., synapse, calcium signaling) and identified novel biological pathways including oxidative stress response, genomic integrity, kinase and small GTPase signaling. Furthermore, involvement of multiple SCZ candidate genes and biological pathways in the pathogenesis of SCZ was suggested in established SCZ-associated CNV loci. Our study shows the high genetic heterogeneity of SCZ and its clinical features and raises the possibility that genomic instability is involved in its pathogenesis, which may be related to the increased burden of de novo CNVs and variable expressivity of CNVs.

Motility and microtubule depolymerization mechanisms of the Kinesin-8 motor, KIF19A

The kinesin-8 motor, KIF19A, accumulates at cilia tips and controls cilium length. Defective KIF19A leads to hydrocephalus and female infertility because of abnormally elongated cilia. Uniquely among kinesins, KIF19A possesses the dual functions of motility along ciliary microtubules and depolymerization of microtubules. To elucidate the molecular mechanisms of these functions we solved the crystal structure of its motor domain and determined its cryo-electron microscopy structure complexed with a microtubule. The features of KIF19A that enable its dual function are clustered on its microtubule-binding side. Unexpectedly, a destabilized switch II coordinates with a destabilized L8 to enable KIF19A to adjust to both straight and curved microtubule protofilaments. The basic clusters of L2 and L12 tether the microtubule. The long L2 with a characteristic acidic-hydrophobic-basic sequence effectively stabilizes the curved conformation of microtubule ends. Hence, KIF19A utilizes multiple strategies to accomplish the dual functions of motility and microtubule depolymerization by ATP hydrolysis.

DOI:http://dx.doi.org/10.7554/eLife.18101.001

The cells that line the airways and other passages in the body have hair-like structures called cilia on their surface. Maintaining the cilia at an appropriate length is key to allowing fluid to flow efficiently in these passages. A protein called tubulin forms scaffolds known as microtubules that give each cilium its shape and allow it to change length.

Motor proteins are also found in cilia, and travel along the microtubules to transport substances. One of these microtubule-based motors, referred to as KIF19A, accumulates at the tip of cilia and controls their length. It does so by combining two actions: it moves along the microtubule to the tip of the cilium, and then removes tubulin molecules from the end. Microtubules are straight along their length and curved at the end, and it is thought that kinesin recognizes both of these shapes in order to carry out these roles. A single region of the KIF19A protein appears to be able to accomplish both roles, but the molecular changes that the protein undergoes to do so are not known.

Wang et al. have now investigated these changes by determining the structure of the motor domain of KIF19A from mice using two experimental approaches: X-ray crystallography and cryo-electron microscopy. These structures showed that the specific structural features responsible for the protein's dual roles are indeed clustered on the side of the protein that binds to the microtubule. Wang et al. also identified the regions that make KIF19A flexible enough to fit this interface with both straight and curved microtubules.

Next, Wang et al. found that other regions of KIF19A stop it detaching from the microtubule and allow it to stabilize the curved shape of microtubule ends; this stimulates the microtubule to disassemble, or “depolymerize”. The findings show that KIF19A uses multiple strategies to enable it to carry out its roles. To understand better how KIF19A depolymerizes the microtubule, a more detailed structure of KIF19A together with tubulin will be needed. Structural studies of KIF19A in cilia will also be useful to understand how the protein controls the length of microtubules.

DOI:http://dx.doi.org/10.7554/eLife.18101.002

Transvenous Embolizations of Venous Compartments of Dural Arteriovenous Fistulas within Venous Sinus Walls

Transvenous embolization of venous compartments within the venous sinus wall was the method initially attempted for closing dural arteriovenous fistulas in 15 patients (22 sinuses). The venous channel, separate from the sinus lumen and located in the venous sinus wall, could be embolized in 6 lesions (3 patients), including 3 superior sagittal sinus fistulas, 2 transverse sinus fistulas, and 1 straight sinus fistula.

This technique resulted in closure of the fistulas and preservation of sinus patency as well as immediate improvement of clinical symptoms. The embolizable venous compartment of the fistula within the venous sinus wall could be detected by preoperative angiography, magnetic resonance imaging, and intraoperative venography. This unique drainage of dural arteriovenous fistulas may develop concurrently with more obvious portions of the fistula.

Transvenous embolization of these venous compartments can close the fistulas and normalize impaired sinus function.

Occult fetomaternal hemorrhage in women with pathological placenta with respect to permeability

AIM

Women with pre-eclampsia (PE), placenta previa (PP), placental abruption (PA), and placental mesenchymal dysplasia (PMD) have been described as having placental permeability dysfunction. This study was performed to determine whether occult fetomaternal hemorrhage (FMH) is common in women with such complications and in women with non-reassuring fetal status.

METHODS

Forty-one antenatal and 39 postnatal blood samples were obtained from 46 women, including 11 with placental permeability dysfunction (5, 3, 2, and 1 with PE, PP, PA, and PMD, respectively) and 35 controls without such complications. To estimate the amount of fetal red blood cells, flow cytometry was performed using the fetal cell count system with two antibodies against fetal hemoglobin and carbonic anhydrase and the β-γ system with two monoclonal antibodies against hemoglobin β-chain and hemoglobin γ-chain. A diagnosis of FMH was made when the fraction size of the isolated cell population on scatter plots expressing fetal hemoglobin alone or hemoglobin γ-chain alone accounted for ≥0.02% of the total cell population on scatter plots.

RESULTS

FMH was identified in five women, including one each with PE, PA, PP, PMD, and no complications. Thus, the prevalence rate of FMH was significantly higher in women with complications than in controls (36% [4/11] vs 2.9% [1/35], respectively, P =  0.009). The FMH occurrence rate did not differ between women with and without non-reassuring fetal status (7.7% [1/13] vs 12% [4/33], respectively, P =  1.000).

CONCLUSION

The risk of fetal red blood cells trafficking into the maternal circulation may be increased in women complicated with PE, PA, PP, and PMD.

RNA-binding motif protein 47 inhibits Nrf2 activity to suppress tumor growth in lung adenocarcinoma

RNA-binding proteins provide a new layer of posttranscriptional regulation of RNA during cancer progression. We identified RNA-binding motif protein 47 (RBM47) as a target gene of transforming growth factor (TGF)-β in mammary gland epithelial cells (NMuMG cells) that have undergone the epithelial-to-mesenchymal transition. TGF-β repressed RBM47 expression in NMuMG cells and lung cancer cell lines. Expression of RBM47 correlated with good prognosis in patients with lung, breast and gastric cancer. RBM47 suppressed the expression of cell metabolism-related genes, which were the direct targets of nuclear factor erythroid 2-related factor 2 (Nrf2; also known as NFE2L2). RBM47 bound to KEAP1 and Cullin 3 mRNAs, and knockdown of RBM47 inhibited their protein expression, which led to enhanced binding of Nrf2 to target genomic regions. Knockdown of RBM47 also enhanced the expression of some Nrf2 activators, p21/CDKN1A and MafK induced by TGF-β. Both mitochondrial respiration rates and the side population cells in lung cancer cells increased in the absence of RBM47. Our findings, together with the enhanced tumor formation and metastasis of xenografted mice by knockdown of the RBM47 expression, suggested tumor-suppressive roles for RBM47 through the inhibition of Nrf2 activity.

NFκB2 Gene as a Novel Candidate that Epigenetically Responds to Interval Walking Training

Physical fitness has been reported to decrease the risk of lifestyle-related diseases. The present study evaluated genome-wide methylation under the hypothesis that interval walking training (IWT) imparted beneficial effects on health, particularly by epigenetically ameliorating susceptibility to inflammation. We screened DNA from peripheral blood samples via genome-wide microarray for genes whose methylation was affected by IWT, paying special attention to promoter regions, and identified over 40 hyper- or hypo-methylated genes following IWT that were not witnessed in controls. We next selected genes in which the degree of methylation change in the promoter region was correlated with energy consumption following IWT. In this way, we found the NFκB2 gene to have increased methylation in multiple regions of its promoter sequence following participation in an exercise regimen. Next, IWT-induced NFκB2 hyper-methylation was confirmed by a quantitative PyroSequencing assessment of methylation in samples obtained from independent subjects who also underwent IWT. The increase in NFκB2 gene promoter methylation by IWT indicates that this regimen may suppress pro-inflammatory cytokines. Thus, these results provide an additional line of evidence that IWT is advantageous in promoting health from an epigenetic perspective by ameliorating susceptibility to inflammation.

X-ray and Cryo-EM structures reveal mutual conformational changes of Kinesin and GTP-state microtubules upon binding

The molecular motor kinesin moves along microtubules using energy from ATP hydrolysis in an initial step coupled with ADP release. In neurons, kinesin-1/KIF5C preferentially binds to the GTP-state microtubules over GDP-state microtubules to selectively enter an axon among many processes; however, because the atomic structure of nucleotide-free KIF5C is unavailable, its molecular mechanism remains unresolved. Here, the crystal structure of nucleotide-free KIF5C and the cryo-electron microscopic structure of nucleotide-free KIF5C complexed with the GTP-state microtubule are presented. The structures illustrate mutual conformational changes induced by interaction between the GTP-state microtubule and KIF5C. KIF5C acquires the 'rigor conformation', where mobile switches I and II are stabilized through L11 and the initial portion of the neck-linker, facilitating effective ADP release and the weak-to-strong transition of KIF5C microtubule affinity. Conformational changes to tubulin strengthen the longitudinal contacts of the GTP-state microtubule in a similar manner to GDP-taxol microtubules. These results and functional analyses provide the molecular mechanism of the preferential binding of KIF5C to GTP-state microtubules.

Endovascular treatment of intractable bleeding from a traumatic pseudoaneurysm of the internal maxillary artery

Traumatic pseudoaneurysms of the internal maxillary artery (IMA) are rare and difficult to treat. A 58-year-old man with a traumatic pseudoaneurysm of the IMA presented with intractable nasal and oral hemorrhage during dual antiplatelet therapy. Transcatheter artery embolization with N-butyl cyanoacrylate (NBCA) completely occluded the pseudoaneurysm. Transcatheter artery embolization with NBCA is a feasible and effective treatment because of its shorter treatment time and lower incidence of recurrence.

B-type natriuretic peptide levels are correlated with birth-weight discordance in monochorionic-diamniotic twins without twin-twin transfusion syndrome

OBJECTIVE

To determine whether B-type natriuretic peptide (BNP) levels in umbilical cord blood (UCB) and amniotic fluid (AF) are correlated with birth-weight discordances in monochorionic-diamniotic twins.

STUDY DESIGN

The UCB-BNP and AF-BNP levels were determined at birth in 36 twin-pairs without twin-twin transfusion syndrome (TTTS).

RESULT

Both the UCB-BNP and the AF-BNP levels were significantly higher among twins with either a birth-weight discordance ≥20% (141.6 versus 52.9 pg ml(-1) for UCB-BNP, 38.0 versus 17.2 pg ml(-1) for AF-BNP) or cardiac dysfunction at birth (167.2 versus 56.3 pg ml(-1) for UCB-BNP, 34.9 versus 19.0 pg ml(-1) for AF-BNP), compared with neonates without the respective characteristics. The UCB-BNP and AF-BNP levels in both the larger and the smaller twins were significantly correlated with birth-weight discordance.

CONCLUSION

Cardiac dysfunction occurs in both larger and smaller co-twins with increasing birth-weight discordances, even in the absence of TTTS.

Sustainable biodegradation of phenolic endocrine-disrupting chemicals by Phragmites australis-rhizosphere bacteria association

The efficacy of two rhizobacteria (Sphingobium fuliginis TIK1 and Sphingobium sp. IT4) of Phragmites australis for the sustainable treatment of water polluted with phenolic endocrine-disrupting chemicals (EDCs) was investigated. Strains TIK1 and IT4 have recently been isolated from Phragmites rhizosphere and shown to degrade various 4-alkylphenols-TIK1 via phenolic ring hydroxylation and meta-cleavage and IT4 via ipso-hydroxylation. The two strains also degraded bisphenol A (BPA), bisphenol B, bisphenol E, bisphenol F, bisphenol P and bisphenol S (BPS). Thus, strains TIK1 and IT4 have wide degradation spectra for phenolic EDCs. The two strains utilized Phragmites root extracts as a sole carbon source and sustainably colonized Phragmites roots, where they degraded phenolic EDCs. In sequencing batch reactor experiments using Phragmites in association with TIK1 or IT4, both associations repeatedly removed phenolic EDCs from polluted secondary effluent water (BPA, BPS, 4-tert-butylphenol, 4-tert-octylphenol and 4-nonylphenol) from polluted secondary effluent water. The results suggest that hydroponic systems using Phragmites-TIK and Phragmites-IT4 associations would be useful for sustainable treatment of polluted waters containing various phenolic EDCs.

Domino model for geomagnetic field reversals

We solve the equations of motion of a one-dimensional planar Heisenberg (or Vaks-Larkin) model consisting of a system of interacting macrospins aligned along a ring. Each spin has unit length and is described by its angle with respect to the rotational axis. The orientation of the spins can vary in time due to spin-spin interaction and random forcing. We statistically describe the behavior of the sum of all spins for different parameters. The term "domino model" in the title refers to the interaction among the spins. We compare the model results with geomagnetic field reversals and dynamo simulations and find strikingly similar behavior. The aggregate of all spins keeps the same direction for a long time and, once in a while, begins flipping to change the orientation by almost 180 degrees (mimicking a geomagnetic reversal) or to move back to the original direction (mimicking an excursion). Most of the time the spins are aligned or antialigned and deviate only slightly with respect to the rotational axis (mimicking the secular variation of the geomagnetic pole with respect to the geographic pole). Reversals are fast compared to the times in between and they occur at random times, both in the model and in the case of the Earth's magnetic field.

Maximum virginiamycin production by optimization of cultivation conditions in batch culture with autoregulator addition

A strategy for optimization of non-growth-associated production in batch culture employing an empirical approach was developed through the study of virginiamycin production. The strategy is formulated with two aims: attaining a high cell concentration at the beginning of the production phase without decrease in production activity; and enhancing the production activity during the production phase. As a practical example, the goal of a maximum virginiamycin (M and S) production in the batch culture of Streptomyces virginiae was set. To attain a high cell concentration in the production phase of the batch culture, that is, to extend the growth phase for as long as possible, the optimum composition and concentration of the complex medium, especially the yeast extract (YE) concentration, were first investigated. Dissolved oxygen (DO) concentration control was also a parameter considered in maintaining the production activity during the production phase. In addition, to enhance the production activity, an optimum addition strategy of an autoregulator, virginiae butanolide-C (VB-C), was investigated. Combining these measures, the optimum cultivation conditions were found to be an initial YE concentration in the complex medium of 45 g/L, the shot addition of 300 mug/L of VB-C 11.5 h after the start of the batch culture, and a DO concentration maintained above 2 mg/L. The maximum concentrations of virginiamycin M and S were about ninefold those obtained under nonoptimum cultivation conditions. Nonoptimum cultivation conditions consisted of an initial YE concentration one sixth (7.5 g/L) that of the optimum cultivation conditions, and no VB-C addition. These conditions were used as representative of the standard cultivation of virginiamycin in this study. The strategy developed here will be applicable to the production of other antibiotics, especially to the cultivation of Streptomyces species, in which a hormonelike signal material (an autoregulator) plays an important role in antibiotic production. (c) 1996 John Wiley & Sons, Inc.

Genome-wide mechanisms of Smad binding

A dual role of transforming growth factor β (TGF-β), to both suppress and promote tumor progression and metastasis, has been well established, but its molecular basis has remained elusive. In this review, we focus on Smad proteins, which are central mediators of the signal transduction of TGF-β family members. We describe current knowledge of cell-type-specific binding patterns of Smad proteins and mechanisms of transcriptional regulation, obtained from recent studies on genome-wide binding sites of Smad molecules. We also discuss potential application of the genome-wide analyses for cancer research, which will allow clarification of the complex mechanisms occurring during cancer progression, and the identification of potential biomarkers for future cancer diagnosis, prognosis and therapy.

"Brush Sign" on susceptibility-weighted MR imaging indicates the severity of moyamoya disease

BACKGROUND AND PURPOSE

SWI is a high spatial resolution MR imaging technique showing magnetic inhomogeneity that could demonstrate increased oxygen extraction in focal cerebral ischemia. The aim of this study was to investigate the characteristics in the signal intensity of DMVs by using SWI and to determine whether this method could indicate the severity of the hemodynamics in MMD by evaluating the correlation between SWI stage and hemodynamics on SPECT.

MATERIALS AND METHODS

Consecutive MMD patients were prospectively analyzed before treatment. Routine MR imaging including SWI was performed, and the number of the conspicuous DMVs draining into the subependymal veins was classified: stage 1, mild (< 5); stage 2, moderate (5-10); and stage 3, severe (> 10). The SWI stage was evaluated in correlation with clinical presentations, and CBF and CVR were quantified by using a SPECT iodine 123 N-isopropyl-p-iodoamphetamine split-dose method.

RESULTS

Patients were 12 males and 21 females (range, 8-66 years), consisting of 4 asymptomatic patients, 13 patients with TIA, 9 patients with infarct, and 7 patients with hemorrhage. There was a significant difference in CVR among clinical presentations, though there was no difference in age, Suzuki stage, or CBF. Conversely, SWI stage was significantly higher in patients with TIA and infarct than asymptomatic patients (P < .01). Higher SWI stage significantly had lower CBF and CVR in the middle cerebral artery area (P < .05).

CONCLUSIONS

SWI stage strongly correlates with ischemic presentations in MMD and also correlates with hemodynamics on SPECT, especially CVR. Increased conspicuity of DMVs, known as "brush sign", could predict the severity of MMD.

Oxidative stress-mediated bimodal regulation of polymorphonuclear leukocyte spreading by polyphenolic compounds

Pyrogallol-bearing polyphenolic compounds induce spreading of polymorphonuclear leukocytes (PMNL), although their optimal concentrations for induction of spreading are quite different (2000, 200, and 2 μM for pyrogallol, (-)-epigallocatechin gallate (EGCG), and tannic acid (TA), respectively), and TA tends to inhibit spreading at higher concentrations. In this study, we examined the involvement of oxidative stress in the regulation of PMNL spreading by these compounds. All three compounds in solution generated H(2)O(2) to a similar extent. Adsorption of the polyphenols to cell surfaces and their accumulation within cells were assessed by detection of the H(2)O(2) precursor O(2)(-) produced by the compounds through reduction of cytochrome c and p-nitro-blue tetrazolium, respectively. TA showed the highest degree of adsorption. EGCG adhered only to PMNL pre-fixed by paraformaldehyde, whereas pyrogallol did not adhere. None of the compounds caused intracellular O(2)(-) generation. A non-pyrogallic compound, 1,2,4-benzenetriol (BT), also produced H(2)O(2); it had no stimulatory effect on PMNL spreading, but inhibited spreading induced by other stimuli. BT did not adhere to PMNL but accumulated within them, and generated O(2)(-) in the presence of glycine. Thiol antioxidants abrogated all of the above spreading-regulatory effects of the polyphenolic compounds. We conclude that H(2)O(2)-generating polyphenols bimodally regulate the spreading of PMNL by subjecting them to oxidative stress. The ability of polyphenol to adhere to, or accumulate within, PMNL may govern the nature of the oxidative stress and determine the optimal concentration of each compound for induction of spreading, as well as whether spreading is promoted or inhibited.

Physical fitness and indices of lifestyle-related diseases before and after interval walking training in middle-aged and older males and females

HYPOTHESIS

Whether increasing peak aerobic capacity for walking (VO(2peak)) by interval walking training (IWT) is closely linked with decreasing the indices of lifestyle-related diseases (LSDs) in middle-aged and older people were examined.

METHODS

For 4 months from April to September 2005 or 2006, 246 males and 580 females (∼65 years) performed IWT consisting of ≥5 sets of fast walking at ≥70% VO(2peak) for 3 min followed by slow walking at ≤40% VO(2peak) for 3 min ≥4 days/week. Before and after IWT, we measured VO(2peak), body mass index (BMI), %body fat, arterial blood pressure, thigh muscle strength and blood parameters. We analysed 198 males and 468 females who had undergone all the measurements both before and after IWT. To examine the hypothesis, we divided the subjects equally into three groups according to their pretraining VO(2peak): low, middle and high groups for each sex.

RESULTS

Before training, it was found that thigh muscle strength and blood high-density lipoprotein cholesterol concentration were lower, whereas body weight, BMI, %body fat, arterial blood pressure and blood glucose were higher in the low group than the high group (all, p<0.05). After training, although VO(2peak) and thigh muscle strength increased and body weight, BMI, %body fat, blood pressure and blood glucose concentration decreased in all groups (all, p<0.05), the changes were greatest in the low group for both sexes.

CONCLUSION

VO(2peak) at baseline and changes in response to training were closely linked with indices of LSDs.

Fractional anisotropy--threshold dependence in tract-based diffusion tensor analysis: evaluation of the uncinate fasciculus in Alzheimer disease

BACKGROUND AND PURPOSE

Tract-based analysis can be used to investigate required tracts extracted from other fiber tracts. However, the fractional anisotropy (FA) threshold influences tractography analysis. The current study evaluated the influence of the FA threshold in measuring diffusion tensor parameters for tract-based analysis of the uncinate fasciculus in subjects with Alzheimer disease (AD).

MATERIALS AND METHODS

Subjects included 30 patients with AD and 10 healthy controls. We acquired tractographies of the uncinate fasciculus by using different FA thresholds. We measured mean FA and the apparent diffusion coefficient (ADC) along the uncinate fasciculus for different FA thresholds and evaluated the correlation between diffusion tensor parameters (FA, ADC) and the Mini-Mental State Examination (MMSE) scores.

RESULTS

The uncinate fasciculus showed lower mean FA and higher mean ADC values in cases with more severe AD. A higher FA threshold led to a lower mean ADC value and a higher mean FA value along the uncinate fasciculus, whereas the relative order of measured values according to the severity of AD was not influenced by the FA threshold. An FA threshold of 0.2 showed higher correlation between mean ADC values and MMSE scores. FA thresholds of 0.15 and 0.20 showed higher correlation between mean FA values and MMSE scores.

CONCLUSIONS

Appropriate selection of the FA threshold leads to higher correlation between diffusion tensor parameters and the severity of AD. For tract-based analysis of degenerative diseases such as AD, appropriate selection of the FA threshold for tractography is important.

Efficacy of DynaCT digital angiography in the detection of the fistulous point of dural arteriovenous fistulas

BACKGROUND AND PURPOSE

Identifying the precise hemodynamic features, including the fistulous point, is essential for treatments of dural arteriovenous fistulas (DAVFs). This study illustrates the efficacy of DynaCT digital angiograms obtained from a 3D C-arm CT to directly visualize the location of the fistulous points in DAVFs.

MATERIALS AND METHODS

This retrospective study observed 14 consecutive patients with DAVFs, which included 7 cavernous sinuses, 4 transverse-sigmoid sinuses, 2 convexity-superior sagittal sinuses, and 1 tentorial sinus. In the assessment of the practical applicability for the diagnosis of DAVFs, images obtained from 2D digital subtraction angiography (DSA) and DynaCT were comparatively evaluated.

RESULTS

In all patients, DynaCT digital angiography could clearly demonstrate the feeding arteries, the fistulous points, and the draining veins. Significant anatomic landmarks for the fistulous points with relationships to osseous structures were also provided. Compared with 2D DSA, DynaCT digital angiograms demonstrated 12 additional findings in 8 patients (57%), including the detection of the fistulous points (n = 7), the feeders (n = 1), the retrograde leptomeningeal drainage (n = 1), the draining veins (n = 1), and the venous anomaly (n = 2).

CONCLUSIONS

In comparison with 2D DSA, DynaCT may provide more detailed information to evaluate DAVFs. DynaCT digital angiograms have a high contrast and isotropic spatial resolution, allowing a reliable visualization of small vessels and fine osseous structures. Such detailed information, especially for the location of the fistulous points, could be very useful for either the endovascular or the surgical treatments of DAVFs.

Comparative analysis of putative periodontopathic bacteria by multiplex polymerase chain reaction

BACKGROUND AND OBJECTIVE

The polymerase chain reaction (PCR) has been applied for the rapid and specific detection of periodontopathic bacteria in subgingival plaque and is potentially of clinical benefit in the diagnosis and treatment of periodontitis subjects. However, several technical points need to be modified before the conventional PCR detection system can be used by clinicians.

MATERIAL AND METHODS

To develop a PCR-based technique more applicable for clinical use than conventional PCR, we established a multiplex PCR for five putative periodontopathic (Treponema denticola, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Tannerella forsythia) and two nonperiodontopathic (Streptococcus sanguinis and Streptococcus salivarius) species of bacteria using whole-plaque suspension as templates, and detected bacteria in subgingival plaque taken from 85 subjects at the supportive periodontal therapy stage after active periodontal treatments.

RESULTS

Among putative periodontopathic bacteria, the detection frequency of T. denticola and P. gingivalis was elevated in parallel with higher probing pocket depth and clinical attachment loss, and had 4.2-14.1 times increasing odds of the clinical parameters tested. Detection of any of the five species of putative periodontopathic bacteria markedly increased the odds ratio of a higher probing pocket depth, clinical attachment loss and bleeding on probing.

CONCLUSION

The multiplex PCR system developed in this study enabled the detection of all the bacteria under investigation in one reaction tube in a less time- and labor-intensive manner than conventional PCR. These results support the potential clinical use of multiplex PCR for detecting periodontopathic bacteria and for evaluating therapeutic strategies and predicting the prognosis for each subject.

Accuracy of pre- and postcontrast 3D time-of-flight MR angiography in patients with acute ischemic stroke: correlation with catheter angiography

BACKGROUND AND PURPOSE

3D time-of-flight (TOF) MR angiography (MRA) is insensitive to slow flow; however, the use of MR imaging contrast agents helps to visualize slow-flow vessels and avoids overestimation of vascular occlusion. The purpose of this study was to correlate pre- and postcontrast 3D TOF MRA with the results of conventional angiography during endovascular reperfusion therapy and to determine the accuracy of postcontrast 3D TOF MRA.

MATERIALS AND METHODS

Thirteen patients who underwent endovascular reperfusion therapy for acute ischemic stroke were retrospectively analyzed. MR imaging techniques included single-slab 3D TOF MRA with and without contrast, as well as perfusion-weighted imaging. Angiography during reperfusion therapy was used as a standard of reference. Affected arteries were divided into segments either proximal or distal to the lesion, and pre- and postcontrast MRA signals were graded as absent, diminished or narrowed, or normal.

RESULTS

In 2 of 5 patients with arterial stenosis and 6 of 8 patients with complete occlusion, MRA signal intensity proximal to each lesion was absent, indicating a proximal pseudo-occlusion on precontrast MRA. Postcontrast MRA demonstrated an arterial signal intensity proximal to the stenotic or occlusive lesions in all 13 patients. Arterial signal intensity distal to the occlusion was identified on postcontrast MRA in 7 of 8 patients having complete occlusion, and the extent of occlusion on postcontrast MRA was similar to results of conventional angiography.

CONCLUSION

In this small series, postcontrast 3D TOF MRA more accurately delineated the extent of stenotic or occlusive arterial lesions than precontrast MRA.