Association of air pollution exposure during pregnancy and early childhood with children's cognitive performance and behavior at age six

BACKGROUND

The impact of air pollution on neurodevelopment in children has attracted much attention in recent times. We aim to clarify the association between prenatal and postnatal air pollutant exposure and children's cognitive performance and behavior at age six.

METHODS

This study was conducted based on a birth cohort study in Japan. Children's intelligence quotient (IQ) was assessed using the Wechsler Intelligence Scale for Children and a score <85 was deemed as low intelligence. A score ≥60 on the Child Behavior Checklist indicated behavioral problems. Exposure to outdoor fine particulate matter (PM2.5) during pregnancy and early childhood was estimated using a spatiotemporal model, while indoor concentrations of air pollutants inside subjects' homes were measured for a week when the child was of ages 1.5 and 3. The associations of exposure to air pollution during pregnancy and after childbirth with cognitive performance and behavior were analyzed using logistic regression models.

RESULTS

The estimated exposure to outdoor PM2.5 during pregnancy and early childhood was not associated with decreased cognitive performance. However, exposure during the first trimester, 0-1 and 3-5 years of age was associated with children's externalizing problems (odds ratios (ORs) were 2.77 [95% confidence interval (CI): 1.05-7.29], 1.66 [95%CI: 1.05-2.62], and 1.80 [95%CI: 1.19-2.74] per interquartile range (IQR) increase, respectively). Exposure to indoor PM2.5 and coarse particles after childbirth was associated with lower full scale IQ (ORs were 1.46 [95%CI: 1.03-2.08] and 1.85 [95%CI: 1.12-3.07] per IQR increase, respectively). However, some inverse associations were also observed.

CONCLUSIONS

These results suggest associations between prenatal and postnatal exposure to outdoor air pollution and behavioral problems, and between indoor air pollution after childbirth and cognitive performance at age six. However, the effects of exposure to outdoor PM2.5 during pregnancy on cognitive performance were not observed.

Factors limiting quantitative phase retrieval in atomic-resolution differential phase contrast scanning transmission electron microscopy using a segmented detector

Quantitative differential phase contrast imaging of materials in atomic-resolution scanning transmission electron microscopy using segmented detectors is limited by various factors, including coherent and incoherent aberrations, detector positioning and uniformity, and scan-distortion. By comparing experimental case studies of monolayer and few-layer graphene with image simulations, we explore which parameters require the most precise characterisation for reliable and quantitative interpretation of the reconstructed phases. Coherent and incoherent lens aberrations are found to have the most significant impact. For images over a large field of view, the impact of noise and non-periodic boundary conditions are appreciable, but in this case study have less of an impact than artefacts introduced by beam deflections coupling to beam scanning (imperfect tilt-shift purity).

Age-related decrease of cholinergic parasympathetic reflex vasodilation in the rat masseter muscle

Skeletal muscle hemodynamics, including that in jaw muscles, is an important in their functions and is modulated by aging. Marked blood flow increases mediated by parasympathetic vasodilation may be important for blood flow in the masseter muscle (MBF); however, the relationship between parasympathetic vasodilation and aging is unclear. We examined the effect of aging on parasympathetic vasodilation evoked by trigeminal afferent inputs and their mechanisms by investigating the MBF during stimulation of the lingual nerve (LN) in young and old urethane-anesthetized and vago-sympathectomized rats. Electrical stimulation of the central cut end of the LN elicited intensity- and frequency-dependent increases in MBF in young rats, while these increases were significantly reduced in old rats. Increases in the MBF evoked by LN stimulation in the young rats were greatly reduced by hexamethonium and atropine administration. Increases in MBF in young rats were produced by exogenous acetylcholine in a dose-dependent manner, whereas acetylcholine did not influence the MBF in old rats. Significant levels of muscarinic acetylcholine receptor type 1 (MR1) and type 3 (MR3) mRNA were observed in the masseter muscle in young rats, but not in old rats. Our results indicate that cholinergic parasympathetic reflex vasodilation evoked by trigeminal afferent inputs to the masseter muscle is reduced by aging and that this reduction may be mediated by suppression of the expression of MR1 and MR3 in the masseter muscle with age.

Characterization and Application of Bioactive Glass and Chitosan Nanoparticles for Tooth Enamel Remineralization

We investigated the remineralization of demineralized enamel surfaces through the application of bioactive glass (BG) and chitosan nanoparticles (CNPs). BG and CNPs were immersed in artificial saliva for 7 days. The resulting crystals were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Embedded enamel blocks were immersed in demineralization solution and then classified into five treatment groups: (1) No material applied; (2) toothpaste containing NaF (F); (3) CNP hydrogel; (4) distilled water slurry containing BG; and (5) CNP hydrogel containing BG (BG-CNP). The enamel blocks were immersed in an artificial saliva solution for 1 month; each material was applied twice per day. Nanoindentation testing of enamel surfaces was performed during the immersion period. We found that unidirectional rod-shaped crystals formed in the artificial saliva solutions treated with BG and BG-CNP, showing multiple XRD peaks for hydroxyapatite. The mechanical properties of enamel surfaces decreased markedly following immersion in the demineralization solution, and significantly recovered after 1 month of BG-CNP and BG treatment compared to other the specimens. Porous demineralized enamel surfaces were filled with a remineralization layer after immersion in saliva and application of NaF, BG, and CNP-BG. Thus, daily application of CNP-BG or BG facilitates enamel remineralization.

Improving the depth resolution of STEM-ADF sectioning by 3D deconvolution

Although the possibility of locating single atom in three dimensions using the scanning transmission electron microscope (STEM) has been discussed with the advent of aberration correction technology, it is still a big challenge. In this report we have developed deconvolution routines based on maximum entropy method (MEM) and Richardson-Lucy algorithm (RLA), which are applicable to the STEM-annular dark-field (ADF) though-focus images to improve the depth resolution. The new three-dimensional (3D) deconvolution routines require a limited defocus-range of STEM-ADF images that covers a whole sample and some vacuum regions. Since the STEM-ADF probe is infinitely elongated along the optical axis, a 3D convolution is performed with a two-dimensional (2D) convolution over xy-plane using the 2D fast Fourier transform in reciprocal space, and a one-dimensional convolution along the z-direction in real space. Using our new deconvolution routines, we have processed simulated focal series of STEM-ADF images for single Ce dopants embedded in wurtzite-type AlN. Applying the MEM, the Ce peaks are clearly localized along the depth, and the peak width is reduced down to almost one half. We also applied the new deconvolution routines to experimental focal series of STEM-ADF images of a monolayer graphene. The RLA gives smooth and high-P/B ratio scattering distribution, and the graphene layer can be easily detected. Using our deconvolution algorithms, we can determine the depth locations of the heavy dopants and the graphene layer within the precision of 0.1 and 0.2 nm, respectively. Thus, the deconvolution must be extremely useful for the optical sectioning with 3D STEM-ADF images.

Effects of polishing with paste containing surface pre-reacted glass-ionomer fillers on enamel remineralization after orthodontic bracket debonding

Surface pre-reacted glass-ionomer (S-PRG) technology allows for the release of multiple ions. This study was performed to investigate the remineralization of etched enamel after removal of the bracket using a novel paste containing S-PRG filler. Surfaces of polished enamel were etched with phosphoric acid and then subdivided into two regions. Bracket bonding resin was thinly applied to one region. After 24-hr immersion in artificial saliva, the bonding resin on the enamel surfaces was removed by grinding with tungsten carbide bur at low-speed, followed by polishing with one of four different polishing systems: (a) nonfluoridated paste (NF); (b) fluoridated paste (F); (c) S-PRG filler-containing paste (S-PRG); or (d) nonfluoridated plus S-PRG filler-containing paste (NF + S-PRG) (n = 15). The polished specimens were then immersed in an artificial saliva solution for 7 days. Nanoindentation testing of enamel surfaces was performed and their mechanical properties were compared. Representative specimens were examined with scanning electron microscope. In all specimens, the mechanical properties of the enamel surfaces were markedly degraded by acid etching. However, the mechanical properties of both regions (etched and resin-infiltrated enamels) showed recovery after polishing and 7-day immersion. Polishing with NF + S-PRG paste led to significant recovery of mechanical properties compared to polishing with NF or S-PRG paste alone, and remineralization was equivalent to that seen with F paste. Porous etched enamel surfaces were filled with a remineralization layer after each polishing procedure and 7-day immersion in all polishing groups. Polishing using NF + S-PRG paste can facilitate enamel remineralization after bracket removal.

Effects of pastes containing ion-releasing particles on dentin remineralization

We investigated the effects of the weekly application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on dentin remineralization. Human dentin blocks were demineralized and polished using pastes containing S-PRG filler (0, 5, and 30%), and then immersed in remineralizing solution for 1 month. Nanoindentation testing was carried out during the immersion period, and the dentin surfaces were examined using scanning electron microscopy. A nano-hydroxyapatite-containing paste was used for comparison. Immersion in demineralization solution had a marked negative effect on the mechanical properties in all specimens. The mechanical properties of specimens polished with S-PRG filler-containing pastes recovered significantly after immersion in remineralization solution for 1 month compared with the other specimens. After remineralization, the open dentinal tubules were filled with a remineralization layer in specimens polished with S-PRG filler-containing and nano-hydroxyapatite-containing pastes. S-PRG filler-containing pastes can aid dentin remineralization.

Visualizing the mixed bonding properties of liquid boron with high-resolution x-ray Compton scattering

Bonding characteristics of liquid boron at 2500 K are studied by using high-resolution Compton scattering. An excellent agreement is found between the measurements and the corresponding Car-Parrinello molecular dynamics simulations. Covalent bond pairs are clearly shown to dominate in liquid boron along with the coexistence of diffuse pairs. Our study reveals the complex bonding pattern of liquid boron and gives insight into the unusual properties of this high-temperature liquid.

Factors associated with lobar vs. non-lobar intracerebral hemorrhage

OBJECTIVES

The relationship between body mass index (BMI) and stroke subtypes has received more research attention than that between BMI and location of intracerebral hemorrhage (ICH). Lobar hemorrhage (LH) differs from non-LH primarily in terms of etiology, i.e. cerebral amyloid angiopathy is the main cause of LH. This study aimed to determine the relationship between BMI and ICH.

MATERIALS AND METHODS

In this retrospective study involving 460 consecutive patients with ICH, BMI was significantly lower in LH than for other ICH locations. BMI categories were underweight (BMI < 18.5 kg/m(2)), normal weight (18.5-23.0 kg/m(2)), overweight (23.0-27.5 kg/m(2)), or obesity (≥27.5 kg/m(2)). Outcome at 1 year was evaluated by the modified Rankin Scale (mRS). We investigated the relationship of BMI and other clinical characteristics with LH and non-LH.

RESULTS

LH was associated with age (>70 years), underweight, unfavorable outcome (mRS ≥3), and daily alcohol consumption. Hypertension and intraventricular bleeding were significantly less common in patients with LH than those with non-LH.

CONCLUSIONS

Alongside risk factors conventionally thought to be related to LH, underweight may also be a LH-related factor, specifically in the elderly.

Persistence of covalent bonding in liquid silicon probed by inelastic x-ray scattering

Metallic liquid silicon at 1787 K is investigated using x-ray Compton scattering. An excellent agreement is found between the measurements and the corresponding Car-Parrinello molecular dynamics simulations. Our results show persistence of covalent bonding in liquid silicon and provide support for the occurrence of theoretically predicted liquid-liquid phase transition in supercooled liquid states. The population of covalent bond pairs in liquid silicon is estimated to be 17% via a maximally localized Wannier function analysis. Compton scattering is shown to be a sensitive probe of bonding effects in the liquid state.

Expression of inwardly rectifying K+ channels in the carotid body of rat

The inwardly rectifying K+ channels, Kir1.1, Kir2.3, Kir4.1-Kir5.1, and Kir4.2-Kir5.1, are candidate chemosensory molecules for CO2/H+. Here, we determined the mRNA expression and immunohistochemical localization of these channels in the carotid body (CB) and petrosal ganglion (PG) of the rat. RT-PCR analysis revealed mRNA expression of Kir4.1 and Kir5.1 in CB, and Kir1.1, Kir4.1, and Kir5.1 in PG. Immunohistochemistry identified the glomus cells in CB to express both Kir4.1 and Kir5.1 protein, while the nerve fibers in CB were immunoreactive for Kir1.1, Kir4.1, and Kir5.1. In the PG, immunoreactivity for Kir1.1, Kir4.1, and Kir5.1 was observed in some ganglion cells. Our findings suggest that Kir channels in the peripheral chemoreceptors play a role in sensing hypercapnic acidosis and maintaining the resting membrane potentials.

3-D finite element analysis and experimental study on brain injury mechanism

The purpose of this paper is to discuss the basic study of mechanism of brain injury analytically and experimentally, in respect to the frequency analysis of the pressure changes. First, a three-dimensional FEM model for impact analysis was presented. The pressure changes inside a brain agar phantom and its frequency analysis were calculated. Second, an experimental system to perform an impact experiment was presented. In the impact experiments, the pressure changes inside a brain agar phantom after impact were measured. The comparison of the computer simulation and the experimental results of the impacts showed that the negative pressure, which seemed to cause the contrecoup injury at the contrecoup side of a brain, also appeared in the contrecoup side of the brain agar phantom. Finally the results of the frequency analysis of pressure changes by FFT were presented. From the results of computer simulations and impact experiments, we found similar spectrums in some frequency bands, which seemed to be the occurrence of the brain injury.

Finite element analysis and experimental study on mechanism of brain injury using brain model

The aim of this study is to discuss the occurrence mechanism of the brain injury analytically and experimentally. In this paper, first, an experimental system to do an impact experiment was presented. The pressure changes inside a brain agar phantom were measured. Second, a three-dimensional FEM model of the impact experiment was constructed. From the results of the fundamental analysis, the transmitted pressure inside the brain agar phantom could be presented. The comparison of the computer simulation and experimental results showed that the negative pressure values, same as the positive pressure occurred in the coup side region of the agar, also appeared in the contrecoup side region of the agar.

Induction of beating by imposed bending or mechanical pulse in demembranated, motionless sea urchin sperm flagella at very low ATP concentrations

A basic feature of the movement of eukaryotic flagella is oscillation. Although flagellar oscillation is thought to be regulated by a self-regulatory feedback system including the mechanical signal of bending itself, the mechanism regulating the dynein motile activity to produce oscillation is not well understood. To elucidate the mechanism, we developed a new experimental system which allowed us to analyze the conditions necessary for the induction of oscillation. When a mechanical signal of bending or a pulse was applied by micromanipulation to a demembranated motionless sea urchin sperm flagellar axoneme at very low ATP concentrations (1-3 microM), a localized pair of bends was induced. The bend formation was often followed by further responses including propagation of the distal bend of paired bends, growth and propagation of the paired bends, and cyclical beating. The beating was induced at 2.0 microM or higher concentrations of ATP, but appeared even at 1.5 microM ATP if a few muM of ADP was also present. When the proximal half of a flagellum was attached to a microneedle, beating could not be induced in the distal free region at 2 microM ATP. These results suggest that mechanical signal is involved in the mechanism regulating the motile activity of dynein to produce oscillation. Our results also showed that the presence of a small amount of ADP and the axial difference along the flagellum are factors essential for the induction of flagellar oscillation.

Synthesis of 5-substituted [N3-15N]-pyrimidine nucleosides: Developing model systems for NMR studies of substituent effects on the N-H...N hydrogen bond in duplex DNA

The effects on various NMR parameters of substitutions, which may influence the hydrogen bond strengths of Watson-Crick-type base pairs, were investigated for DNA dodecamers containing 5-substituted-2'-deoxyuridine derivatives in oligomers, 5'-d(CGCGAATXCGCG)-3', where A and X were [ul-15N]-2'-deoxyadenosine and [3(-15)N]-2'-deoxyuridine derivatives. The substitution effects on the NMR parameters were linearly correlated with the pKa values of the 2'-deoxyuridine derivatives.

Origin of cytoplasm substituted rice cultivars found in Japan

Genetic variation of Japanese rice cultivars were examined. Five of 450 lowland cultivars and another five of 200 upland cultivars were determined as the indica type by using isozyme genotypes and the remainder were of the japonica type. The major characteristics of these indica cultivars, revealed a slender shape of grains, a short apiculus hair length, a positive allele for Ph reaction, and allele-3 for the Pgd1 locus. Three of these indica cultivars showed a non-deletion ORF100, which is essential to the japonica-type plastid. The plastid subtype identity (PS-ID) sequences of these plastids is 6C7A, which is also a japonica-specific repeat unit. Thus, these cultivars were concluded to be naturally generated cytoplasm substituted lines. These plastids were introduced into a indica genetic background from japonica cultivars grown elsewhere. The rest of the indica cultivars revealed a deletion-type ORF100 and plastid subtype 8C8A, both of which are indica-specific. These cultivars carried indica-type allelic constitutions for diagnostic isozyme loci. However, other characters were identical to the cytoplasm-substituted cultivars in Japan. In East and Southeast Asia, cultivars carrying a indica-type nuclear genotype with a japonica-type plastid are restricted to Aus cultivars in the Bengal region. Genetic and historical records suggest that Japanese indica cultivars and the Aus cultivars are closely related. The Aus cultivars acquire necessary genetic constitutions from both indica and japonica cultivars through naturally occurring out-crossing to adapt to a particular cultivation condition in the region. The wide adaptability enabled them to be introduced into a northern region like Japan.

Analysis of the duplicated CHS1 gene related to the suppression of the seed coat pigmentation in yellow soybeans

Seed coat color in soybean is controlled by the classically defined I ( Inhibitor) locus. The seeds of most commercial soybean varieties are yellow due to the presence of a dominant allele of the I locus ( I: yellow seed coat, or i(i) : pigmented hilum and yellow seed coat), which inhibits seed coat pigmentation. Analysis of spontaneous mutations from I (yellow seed coat) to i (pigmented seed coat) has shown that these mutations are correlated with the deletion of a duplicated chalcone synthase gene-1 ( CHS1) region. In the current study, we isolated the duplicated CHS1 region from a soybean cultivar with a I/I genotype (cv Miyagi shirome) and determined its structure. The results showed that the duplicated CHS1 contained intact regulatory and coding regions. We designated the duplicated CHS1 as ICHS1. In the hypocotyls of Miyagi shirome, the cDNA derived from ICHS1 mRNA was identified by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, whereas in the immature seed coats it was suggested that the amount of transcripts from ICHS1 and/or another type of CHS1 ( CHS1.1) was very low. Interestingly, in the Miyagi shirome genome with a I/I genotype, ICHS1 was closely linked to the truncated CHS3, and sequence comparison showed that this cluster probably arose from the CHS1-CHS3 cluster by a 1.8-kb deletion event.

Different maternal origins of Japanese lowland and upland rice populations

Plastid subtype ID (PS-ID) sequences were determined from sequence data based on CA repeats between genes rpl16 and rpl14 in Japanese lowland and upland cultivars. The PS-ID sequences of Japanese rice cultivars showed that there are different maternal origins between lowland and upland cultivars. One subtype, 6C7A, of PS-ID sequences was predominant in all but one Japanese lowland cultivar and carried a combination of the indica-specific subtype 8C8A and japonica-specific nuclear markers for the isozyme genotype. It is probably a nuclear-cytoplasmic recombinant resulting from natural out-crossing and succeeding self-pollination. The origin of the plastid was re-confirmed by the existence of an indica-specific deletion in the plastid genome. In contrast, the Japanese upland cultivars showed two subtypes, 7C6A and 6C7A, of PS-ID sequences. An upland-specific isozyme allele as a nuclear marker was equally predominant in cultivars carrying each subtype. The existence of these particular upland-specific nuclear and cytoplasmic genotypes suggests that the origin of Japanese upland cultivars is different from that of Japanese lowland cultivars. Cultivars carrying the upland-specific nuclear genotype are common in Southeast Asia, but the combination of the upland-specific nuclear and cytoplasmic genotypes which is the same as the Japanese upland predominant type was found in cultivars only in Taiwan and Indonesia. Japanese upland cultivars are closely related to those cultivars.

Extensive trans-species mitochondrial polymorphisms in the carabid beetles Carabus subgenus Ohomopterus caused by repeated introgressive hybridization

To study the potential importance of introgressive hybridization to the evolutionary diversification of a carabid beetle lineage, we studied intraspecific and trans-species polymorphisms in the mitochondrial NADH dehydrogenase subunit 5 (ND5) gene sequence (1083 bp) in four species of the subgenus Ohomopterus (genus Carabus) in central and eastern Honshu, Japan. Of the four species, C. insulicola is parapatric with the other three, and can hybridize naturally with at least two. This species possesses two haplotypes of remote lineages. We classified ND5 haplotypes using polymerase chain reaction-restriction fragment length polymorphism with TaqI endonuclease for 524 specimens, and sequenced 143 samples. Analysis revealed that each species was polyphyletic in its mitochondrial DNA phylogeny, representing a marked case of trans-species polymorphism. Recent one-way introgression of mitochondria from C. arrowianus nakamurai to C. insulicola, and from C. insulicola to C. esakii, was inferred from the frequency of identical sequences between these species and from direct evidence of hybridization in their contact zones. Other intraspecific polymorphisms in the four species may be due to undetected introgressive hybridization (e.g. C. insulicola to C. maiyasanus) or from stochastic lineage sorting of ancestral polymorphisms. This beetle group has a genital lock-and-key system, with species-specific or subspecies-specific genital morphology that may act as a barrier to hybridization. However, our results demonstrate that introgressive hybridization has occurred multiple times, at least for mitochondria, despite differences among, and stability within, morphological characters that distinguish local populations. Thus, hybridization and introgression could have been key processes in the evolutionary diversification of Ohomopterus.

[Drugs that modulate the cellular function of calcium ion]

Cytoplasmic Ca(2+) concentration is kept low level of about 10(-7)M. When Ca(2+) concentration increases by specific stimuli via opening of channel proteins, Ca(2+) binds to Ca(2+)-binding proteins, activating specific proteins, results in responding the stimuli. In this report, we summarize the effect of drugs, of which targets are the proteins above, including Ca(2+)-pump, ion exchanger, ion channels, calmodulin and calmodulin-binding proteins, and other Ca(2+) binding proteins.

Reconstruction of urinary tract utilizing transverse colon conduit for a cystectomized patient with post-ureterocutaneostomy complications and sigmoid colon cancer

A seventy-four years old man had been suffering from symptomatic and infectious complications associated with conjoined cutaneoureterostomy following the radical cystectomy for advanced transitional cell carcinoma of the bladder 3 years ago. He underwent urinary reconstruction using transverse colon conduit after diagnostic exclusion of recurrent urothelial tumor in the upper urinary tract, evaluation of performance status and endoscopic examination of the colon. Enteroscopy incidentally revealed he had an early stage adenocarcinoma in his sigmoid colon to be resected, and the resection was followed by the urinary diversion. Postoperatively he is satisfied to be free from urinary complications and frequently visits the outpatient clinic for painful and troublesome ureteral catheter exchange.

A highly sensitive method for measurement of myosin ATPase activity by reversed-phase high-performance liquid chromatography

A new method for measurement of myosin ATPase activity has been developed utilizing reversed-phase high-performance liquid chromatography (HPLC), which detects as low as 0.05 nmol of ADP hydrolyzed from ATP. After termination of the ATPase reaction by addition of perchloric acid, the hydrolysate ADP and substrate ATP were separated by reversed-phase HPLC. The absorbance of ADP was monitored at 259 nm, and the amount of ADP was quantified from its peak area on the chromatogram by use of the NIH Image computer software. Our method showed linearity over a wide range from 0.05 to 10 nmol of ADP per 20 microl with a coefficient of determination (r(2)) of 0.99. Myosin ATPase activities determined by the HPLC method were almost identical to those determined by the malachite green method, a widely used spectrophotometric method with range of detection from 1 to 8 nmol of phosphate. Because our method requires only a small volume of reaction solution, it will be a powerful tool for measuring ATPase activity of motor proteins, which are difficult to obtain in large amount.

New rat model for attention deficit hyperactive disorder (ADHD)

PURPOSE

In a strain of the Long-Evans Cinnamon (LEC) rats, we found spontaneously hyperactive animals designated as "wiggling," and established a congenic wiggling (Wig) rat by transferring the gene from the LEC to the Wistar King-Aptekman/Hokkaido (WKAH) strain. We evaluated the feasibility of the Wig rat for an animal model of human attention deficit hyperactive disorder (ADHD).

METHODS

Mode of inheritance was examined by use of linkage analyses. Motor activity, behavior, and working memory were assessed by use of electric digital counters, open field test, and Y-maze and water-maze tests.

RESULTS

The abnormal behavior, including hyperactivity, was transmitted in autosomal recessive mode. Diurnal and nocturnal motor activity of 12- to 14-week-old Wig rats was markedly higher than that of controls, and this hyperactivity was more prominent during nighttime than daytime. Ambulation in the open-field test was significantly increased in Wig rats, but rearing was decreased in Wig rats, compared with controls. Results of the Y-maze tests indicated that spontaneous alternation behavior was significantly impaired in Wig rats, although there was no difference in the total arm entries. The water-maze test could not be performed because, when exposed to water, Wig rats panicked and almost drowned.

CONCLUSIONS

Wig rats are hyperactive and have impaired working memory and impulsive behavior, as assessed by the motor activity and open-field tests and the Y-maze test, and these abnormalities are transmitted by a single gene with Mendelian pattern. Wig rats represent an excellent animal model of human ADHD.

Hyponatremia with increased plasma antidiuretic hormone in a case of hypothyroidism

We report a 70-year-old woman with hypothyroidism and severe hyponatremia. Her plasma antidiuretic hormone (ADH) level was inappropriately high for her low plasma osmolality. Her low serum sodium level was gradually corrected by water restriction and sodium supplementation prior to the initiation of thyroid hormone replacement. After a diagnosis of Hashimoto's thyroiditis had been made, the patient was treated with levothyroxine. Following this treatment, the patient's serum sodium level increased drastically. It is suggested that the elevated plasma ADH level played an important role in the development of hyponatremia in this case.

Retinal fascin: functional nature, subcellular distribution, and chromosomal localization

PURPOSE

To investigate the functional properties, subcellular localization, and chromosomal location of retinal fascin.

METHODS

Recombinant retinal fascin protein was prepared by using a baculovirus-insect expression system. Actin-binding and -bundling assays were performed with chick actin purified from skeletal muscle. Western blot analysis and immunohistochemistry were performed with a polyclonal antibody raised against bovine retinal fascin. A human retinal cDNA library was screened with an expressed sequence tag cDNA fragment. Chromosomal location was determined with fluorescent in situ hybridization.

RESULTS

The actin-binding and actin-bundling activities of retinal fascin were demonstrated by high- and low-speed centrifugation assays. Formation of filamentous (F)-actin bundles by retinal fascin in vitro was also morphologically confirmed by fluorescence microscopy and electron microscopy. Immunohistochemical analysis revealed that retinal fascin protein was localized specifically in the outer and inner segments of the photoreceptor cells in the retina. Two splicing variants of human retinal fascin cDNA were also located. One clone encoded 492 amino acids, and the other encoded 516 amino acids. The gene encoding retinal fascin was localized to human chromosome 17, region q24 -25.

CONCLUSIONS

These results suggest that retinal fascin may play a role in formation of unique morphologic structures of the photoreceptor cells and is a candidate gene for retinal degenerative disorders.

Stable transfectants of smooth muscle cell line lacking the expression of myosin light chain kinase and their characterization with respect to the actomyosin system

We constructed a plasmid vector having a 1.4-kilobase pair insert of myosin light chain kinase (MLCK) cDNA in an antisense direction to express antisense mRNA. The construct was then transfected to SM3, a cell line from vascular smooth muscle cells, producing a few stable transfectants. The down-regulation of MLCK expression in the transfectants was confirmed by both Northern and Western blots. The control SM3 showed chemotaxic motility to platelet-derived growth factor-BB, which was supported by lamellipodia. However, the transfectants showed neither chemotaxic motility nor developed lamellipodia, indicating the essential role of MLCK in the motility. The specificity for the targeting was assessed by a few tests including the rescue experiment. Despite this importance of MLCK, platelet-derived growth factor-BB failed to induce MLC20 phosphorylation in not only the transfectants but also in SM3. The mode in which MLCK was involved in the development of membrane ruffling is discussed with special reference to the novel property of MLCK that stimulates the ATPase activity of smooth muscle myosin without phosphorylating its light chain (Ye, L.-H., Kishi, H., Nakamura, A., Okagaki, T., Tanaka, T., Oiwa, K., and Kohama, K. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 6666-6671).

Domain analysis of the actin-binding and actin-remodeling activities of drebrin

Drebrin is an actin-binding protein which is expressed at highly levels in neurons. When introduced into fibroblasts, it has been known to bind to F-actin and to cause remodeling of F-actin. Here, we performed a domain analysis of the actin-binding and actin-remodeling activities of drebrin. Various fragments of drebrin cDNA were fused with green fluorescent protein cDNA and introduced into Chinese hamster ovary cells. Association of the fusion protein with F-actin and remodeling of the F-actin were examined. We found that the central 85-amino-acid sequence (residues 233-317) was sufficient for the binding to and remodeling of F-actin. The binding activity of this fragment was relatively low compared with that of full-length drebrin, but all the types of abnormalities of F-actin that are observed with full-length drebrin were also observed with this fragment. When this sequence was further fragmented, the actin-binding activity was greatly reduced and the actin-remodeling activity disappeared. The actin-binding activity of the central region of drebrin was confirmed by a cosedimentation assay of chymotryptic fragments of drebrin with purified actin. These data indicate that the actin-binding domain and actin-remodeling domain are identical and that this domain is located at the central region of drebrin.

An allele of the ripening-specific 1-aminocyclopropane-1-carboxylic acid synthase gene (ACS1) in apple fruit with a long storage life

An allele of the 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene (Md-ACS1), the transcript and translated product of which have been identified in ripening apples (Malus domestica), was isolated from a genomic library of the apple cultivar, Golden Delicious. The predicted coding region of this allele (ACS1-2) showed that seven nucleotide substitutions in the corresponding region of ACS1-1 resulted in just one amino acid transition. A 162-bp sequence characterized as a short interspersed repetitive element retrotransposon was inserted in the 5'-flanking region of ACS1-2 corresponding to position -781 in ACS1-1. The XhoI site located near the 3' end of the predicted coding region of ACS1-2 was absent from the reverse transcriptase-polymerase chain reaction product, revealing that exclusive transcription from ACS1-1 occurs during ripening of cv Golden Delicious fruit. DNA gel-blot and polymerase chain reaction analyses of genomic DNAs showed clearly that apple cultivars were either heterozygous for ACS1-1 and ACS1-2 or homozygous for each type. RNA gel-blot analysis of the ACS1-2 homozygous Fuji apple, which produces little ethylene and has a long storage life, demonstrated that the level of transcription from ACS1-2 during the ripening stage was very low.

Enhanced expression and differential inducibility of soybean chalcone synthase genes by supplemental UV-B in dark-grown seedlings

By developing gene-specific RT-PCR and using filters to allow transmission down to 290 nm (UV-B+) or blocking all radiation below 320 nm (UV-B(-)), the effect of UV-B+ and UV-B- light on expression of each of the presently known seven members of soybean chalcone synthase (CHS) gene family in dark-grown seedlings was analyzed. Dark expression was detectable already in 18 h dark-germinating embryos, with progressive increases on successive days, suggesting that chs belongs to a class of genes expressed very early during germination, and that the expression at this stage is either constitutive or induced by non-light-dependent factors present in the seed or made available following imbibition. Exposure of 18 h dark-germinating embryos to UV-B- or to UV-B+ light did not lead to an increase in chs signal. However, the 24 h dark-germinating embryos showed a distinct effect of UV-B+, interestingly coinciding with the stage when the head of seedlings was in the process of being pushed up above ground by stem elongation, suggesting the possibility of a developmental switch modulating the appearance of UV-B response. The response to UV-B- was most prominent in chs1 and almost silent in chs2, while the up-regulation by UV-B+ was most prominent in chs5 and chs6 and much less so in chs2. Interestingly, chs2 was noted to be the only member of the Gmchs gene family devoid of H-box, raising the possibility that the H-box may be a good indicator of the photo-inducibility of a chs gene.

Regulation of actin binding and actin bundling activities of fascin by caldesmon coupled with tropomyosin

Human fascin is an actin-bundling protein and is thought to play a role in the formation of microfilament bundles of microspikes and stress fibers in cultured cells. To explore the regulation of fascin-actin interaction, we have examined the effects of culture cell caldesmon and tropomyosin (TM) on actin binding activity of human fascin. Caldesmon alone or TM alone has little or no effect on the actin binding of fascin. However, caldesmon together with TM completely inhibits actin binding of human fascin. When calmodulin is added, the inhibition of fascin-actin interaction by caldesmon and TM becomes Ca2+ dependent because Ca2+/calmodulin blocks actin binding of caldesmon. Furthermore, as phosphorylation of caldesmon by cdc2 kinase inhibits actin binding of caldesmon, phosphorylation can also control actin binding of fascin in the presence of TM. As expected by the inhibition of fascin-actin binding, caldesmon coupled with TM also inhibits actin bundling activity of fascin. Whereas smooth muscle caldesmon alone or TM alone shows no effect, caldesmon together with TM completely inhibits actin bundling activity of fascin. This inhibition is again Ca2+ dependent when calmodulin is added to the system. These results suggest important roles for caldesmon and TM in the regulation of the function of human fascin.

The surgical treatment of lung lacerations and major bronchial disruptions caused by blunt thoracic trauma

The records of 16 patients who suffered blunt thoracic trauma, causing lung lacerations in 13, bronchial disruptions in 2, and lung laceration with bronchial disruption in 1, were reviewed to investigate the correlations between clinical factors and prognosis. The causes of these injuries included 14 traffic accidents and 2 construction-related accidents, and the indications for surgery were massive bleeding in 12 patients, massive air leakage in 2, both in 1, and lung abscess in 1. Of the 16 patients, 11 (68.8%) underwent thoracotomy less than 4 h after admission, 3 (18.8%) underwent thoracotomy 4 to 24 h after admission, and 2 (12.5%) underwent thoracotomy 24 h or later after admission. The operative techniques included 1 pneumonectomy, 5 lobectomies, 2 bronchoplasties, and 8 minor repairs. The mortality rate was 43.7%, which included six early deaths occurring within 72 h of the trauma, and one late death. While major bronchial disruption is usually associated with a good prognosis, univariate and multivariate analyses demonstrated that intrapleural bleeding of 300 ml/h or more from time of trauma to chest tube drainage was significantly correlated with a poor prognosis. Moreover, an injury severity score (ISS) of 36 or more showed a trend toward a correlation with poor prognosis in patients with lung lacerations. Prompt thoracotomy will decrease mortality rate of patients suffering lung lacerations resulting in intrapleural bleeding of more than 300 ml/h.

Aortic root replacement for Takayasu arteritis associated with ulcerative colitis and ankylosing spondylitis--report of a case

A 26-year-old man was admitted for treatment of congestive heart failure resulting from aortic regurgitation. The patient had been on medical treatment for ulcerative colitis (UC) since he was 14 years old and for ankylosing spondylitis (AS) since he was 20 years old. On admission, gradients of blood pressure among the extremities were observed. Echocardiography revealed marked dilation of the left ventricle (LV), hypokinetic wall motion of the LV, slightly prolapsed aortic cusps with annular dilatation, and severe aortic regurgitation. Computed tomographic scans demonstrated an aneurysmal dilation of the ascending aorta and thickening of the descending and abdominal aortic wall. Digital subtraction angiography demonstrated an aneurysmal dilation of the ascending aorta; however, there was no clear evidence of steno-occlusive lesions in the brachiocephalic vessels. Blood studies showed positive inflammatory signs and negative rheumatoid factor. HLA typing showed A2, 24(9), B27, 67, Cw1, 7, and DR1, 2. Based on these data, the diagnosis of Takayasu arteritis associated with UC and AS was made. Aortic root replacement was performed. Steroid therapy was restarted immediately after surgery. Histologic studies of the aortic wall showed findings compatible with Takayasu arteritis. The combination of these rare diseases suggests that they have a common pathophysiologic background.