Risk and Resilience in Trajectories of Post-Traumatic Stress Symptoms among First Responders after the 2011 Great East Japan Earthquake: a 7-year prospective cohort study

Introduction

First responders to disasters are at risk of developing post-traumatic stress disorder (PTSD). The trajectories of post-traumatic stress symptom severity differ among individuals, even if they are exposed to similar events. These trajectories have not yet been reported in non-Western first responders.

Objectives

We aimed to explore post-traumatic stress symptom severity trajectories and their risk factors in first responders to the 2011 Great East Japan Earthquake (GEJE)— a historically large earthquake that resulted in a tsunami and a nuclear disaster.

Methods

56 388 Japan Ground Self-Defense Force (JGSDF) personnel dispatched to the GEJE were enrolled in this seven-year longitudinal cohort study. PTSD symptom severity was measured using the Impact of Event Scale-Revised (IES-R). Trajectories were identified using latent growth mixture models (LGMM). Nine potential risk factors for the symptom severity trajectories were analyzed using multinomial logistic regression.

Results

Five symptom severity trajectories were identified: “resilient” (54.7%), “recovery” (24.5%), “incomplete recovery” (10.7%), “late-onset” (5.7%), and “chronic” (4.3%). The main risk factors for the four non-resilient trajectories were older age, personal disaster experiences, and working conditions. These working conditions included duties involving body recovery or radiation exposure risk, longer deployment length, later or no post-deployment leave, and longer post-deployment overtime.

Conclusions

The majority of first responders to GEJE were resilient and developed few or no PTSD symptoms. A substantial minority experienced late-onset and chronic symptom severity trajectories. The identified risk factors can inform policies for prevention, early detection, and intervention in individuals at risk of developing symptomatic trajectories.

Disclosure

No significant relationships.

Artificial Intelligence and Acute Stroke Imaging

Artificial intelligence technology is a rapidly expanding field with many applications in acute stroke imaging, including ischemic and hemorrhage subtypes. Early identification of acute stroke is critical for initiating prompt intervention to reduce morbidity and mortality. Artificial intelligence can help with various aspects of the stroke treatment paradigm, including infarct or hemorrhage detection, segmentation, classification, large vessel occlusion detection, Alberta Stroke Program Early CT Score grading, and prognostication. In particular, emerging artificial intelligence techniques such as convolutional neural networks show promise in performing these imaging-based tasks efficiently and accurately. The purpose of this review is twofold: first, to describe AI methods and available public and commercial platforms in stroke imaging, and second, to summarize the literature of current artificial intelligence-driven applications for acute stroke triage, surveillance, and prediction.

Effects of pruritogens and algogens on rostral ventromedial medullary ON and OFF cells

Rostroventromedial medulla (RVM) ON and OFF cells are thought to facilitate and inhibit spinal nociceptive transmission, respectively. However, it is unknown how ON and OFF cells respond to pruritic stimuli or how they contribute to descending modulation of spinal itch signaling. In pentobarbital sodium-anesthetized mice, single-unit recordings were made in RVM from ON and OFF cells identified by their respective increase or decrease in firing that occurred just before nocifensive hindlimb withdrawal elicited by paw pinch. Of RVM ON cells, 75% (21/28) were excited by intradermal histamine, 50% (10/20) by intradermal chloroquine, and 75% (27/36) by intradermal capsaicin. Most chemically responsive units also responded to a scratch stimulus applied to the injected hindpaw. Few ON cells responded to intradermal injection of vehicle (saline: 5/32; Tween 2/17) but still responded to scratching. For OFF cells, intradermal histamine and scratching inhibited 32% (6/19) with no effect of histamine in the remainder. Intradermal chloroquine inhibited 44% (4/9) and intradermal capsaicin inhibited 61% (11/18) of OFF cells. Few OFF cells were affected by vehicles (Tween: 1 inhibited, 7 unaffected; saline: 3 excited, 1 inhibited, 8 unaffected). Both ON and OFF cells that responded to one chemical usually also responded to others, whereas units unresponsive to the first-tested chemical tended not to respond to others. These results indicate that ascending pruriceptive signals activate RVM ON cells and inhibit RVM OFF cells. These effects are considered to facilitate and disinhibit spinal pain transmission, respectively. It is currently not clear if spinal itch transmission is similarly modulated. NEW & NOTEWORTHY The rostroventromedial medulla (RVM) contains ON and OFF cells that are, respectively, excited and inhibited by noxious stimuli and have descending projections that facilitate and inhibit spinal nociceptive transmission. Most RVM ON cells were excited, and OFF cells inhibited, by intradermal injection of the pruritogens histamine and chloroquine, as well as the algogen capsaicin. These results indicate that itchy stimuli activate RVM neurons that presumably give rise to descending modulation of spinal itch transmission.

Innocuous warming enhances peripheral serotonergic itch signaling and evokes enhanced responses in serotonin-responsive dorsal horn neurons in the mouse

Itch is often triggered by warming the skin in patients with itchy dermatitis, but the underlying mechanism is largely unknown. We presently investigated if warming the skin enhances histamine- or serotonin (5-HT)-evoked itch behavior or responses of sensory dorsal root ganglion (DRG) cells, and if responses of superficial dorsal horn neurons to innocuous warming are enhanced by these pruritogens. In a temperature-controlled environmental chamber, mice exhibited greater scratching following intradermal injection of 5-HT, but not histamine, SLIGRL, or BAM8-22, when the skin surface temperature was above 36°C. Calcium imaging of DRG cells in a temperature-controlled bath revealed that responses to 5-HT, but not histamine, were significantly greater at a bath temperature of 35°C vs. lower temperatures. Single-unit recordings revealed a subpopulation of superficial dorsal horn neurons responsive to intradermal injection of 5-HT. Of these, 58% responded to innocuous skin warming (37°C) prior to intradermal injection of 5-HT, while 100% responded to warming following intradermal injection of 5-HT. Warming-evoked responses were superimposed on the 5-HT-evoked elevation in firing and were significantly larger compared with responses pre-5-HT, as long as 30 min after the intradermal injection of 5-HT. Five-HT-insensitive units, and units that either did or did not respond to intradermal histamine, did not exhibit any increase in the incidence of warmth sensitivity or in the mean response to warming following intradermal injection of the pruritogen. The results suggest that 5-HT-evoked responses of pruriceptors are enhanced during skin warming, leading to increased firing of 5-HT-sensitive dorsal horn neurons that signal nonhistaminergic itch.

NEW & NOTEWORTHY

Skin warming often exacerbates itch in patients with itchy dermatitis. We demonstrate that warming the skin enhanced serotonin-evoked, but not histamine-evoked, itch behavior and responses of sensory dorsal root ganglion cells. Moreover, serotonin, but not histamine, enhanced responses of superficial dorsal horn neurons to innocuous warming. The results suggest that skin warming selectively enhances the responses of serotonin-sensitive pruriceptors, leading to increased firing of serotonin-sensitive dorsal horn neurons that signal nonhistaminergic itch.

The longitudinal mental health impact of Fukushima nuclear disaster exposures and public criticism among power plant workers: the Fukushima NEWS Project study

BACKGROUND

The Fukushima Daiichi and Daini Nuclear Power Plant workers experienced multiple stressors as both victims and onsite workers after the 2011 Great East Japan Earthquake and subsequent nuclear accidents. Previous studies found that disaster-related exposures, including discrimination/slurs, were associated with their mental health. Their long-term impact has yet to be investigated.

METHOD

A total of 968 plant workers (Daiichi, n = 571; Daini, n = 397) completed self-written questionnaires 2-3 months (time 1) and 14-15 months (time 2) after the disaster (response rate 55.0%). Sociodemographics, disaster-related experiences, and peritraumatic distress were assessed at time 1. At time 1 and time 2, general psychological distress (GPD) and post-traumatic stress response (PTSR) were measured, respectively, using the K6 scale and Impact of Event Scale Revised. We examined multivariate covariates of time 2 GPD and PTSR, adjusting for autocorrelations in the hierarchical multiple regression analyses.

RESULTS

Higher GPD at time 2 was predicted by higher GPD at time 1 (β = 0.491, p < 0.001) and discrimination/slurs experiences at time 1 (β = 0.065, p = 0.025, adjusted R 2 = 0.24). Higher PTSR at time 2 was predicted with higher PTSR at time 1 (β = 0.548, p < 0.001), higher age (β = 0.085, p = 0.005), and discrimination/slurs experiences at time 1 (β = 0.079, p = 0.003, adjusted R 2 = 0.36).

CONCLUSIONS

Higher GPD at time 2 was predicted by higher GPD and discrimination/slurs experience at time 1. Higher PTSR at time 2 was predicted by higher PTSR, higher age, and discrimination/slurs experience at time 1.

High transmission Ni compound refractive lens for high energy X-rays

We present a new planar Ni compound refractive lens for high energy X-rays (116 keV). The lens is composed of identical plano-concave elements with longitudinal parabolic grooves manufactured by a punch technique. In order to increase the lens transmission, the thickness of the single lens at the parabolic groove vertex was reduced to less than 5 μm and the radius of curvature was reduced to about 20 μm. The small radius of curvature allowed us to reduce the number of single elements needed to get the focal length of 3 m to 54 single lenses. The gain parameter has been significantly improved compared to the previous lenses due to higher transmission, but the focused beam size and its gain are not as good as expected, mostly due to the aberrations caused by the lens shape imperfections.

Intradermal endothelin-1 excites bombesin-responsive superficial dorsal horn neurons in the mouse

Endothelin-1 (ET-1) has been implicated in nonhistaminergic itch. Here we used electrophysiological methods to investigate whether mouse superficial dorsal horn neurons respond to intradermal (id) injection of ET-1 and whether ET-1-sensitive neurons additionally respond to other pruritic and algesic stimuli or spinal superfusion of bombesin, a homolog of gastrin-releasing peptide (GRP) that excites spinal itch-signaling neurons. Single-unit recordings were made from lumbar dorsal horn neurons in pentobarbital-anesthetized C57BL/6 mice. We searched for units that exhibited elevated firing after id injection of ET-1 (1 μg/μl). Responsive units were further tested with mechanical stimuli, bombesin (spinal superfusion, 200 μg·ml(-1)·min(-1)), heating, cooling, and additional chemicals [histamine, chloroquine, allyl isothiocyanate (AITC), capsaicin]. Of 40 ET-1-responsive units, 48% responded to brush and pinch [wide dynamic range (WDR)] and 52% to pinch only [high threshold (HT)]. Ninety-three percent responded to noxious heat, 50% to cooling, and >70% to histamine, chloroquine, AITC, and capsaicin. Fifty-seven percent responded to bombesin, suggesting that they participate in spinal itch transmission. That most ET-1-sensitive spinal neurons also responded to pruritic and algesic stimuli is consistent with previous studies of pruritogen-responsive dorsal horn neurons. We previously hypothesized that pruritogen-sensitive neurons signal itch. The observation that ET-1 activates nociceptive neurons suggests that both itch and pain signals may be generated by ET-1 to result in simultaneous sensations of itch and pain, consistent with observations that ET-1 elicits both itch- and pain-related behaviors in animals and burning itch sensations in humans.

Behavioral model of itch, alloknesis, pain and allodynia in the lower hindlimb and correlative responses of lumbar dorsal horn neurons in the mouse

We have further developed a behavioral model of itch and pain in the lower hindlimb (calf) originally reported by LaMotte et al. (2011) that allows comparisons with responses of lumbar dorsal horn neurons to pruritic and noxious stimuli. Intradermal (id) microinjection of the pruritogens histamine, SLIGRL-NH2 (agonist of PAR-2 and MrgprC11) and chloroquine (agonist of MrgprA3) into the calf of the lower limb elicited significant biting and a small amount of licking directed to the injection site, over a 30-min time course. Following id injection of histamine, low-threshold mechanical stimuli reliably elicited discrete episodes of biting (alloknesis) over a longer time course; significantly less alloknesis was observed following id injection of SLIGRL-NH2. Capsaicin injections elicited licking but little biting. Following id injection of capsaicin, low-threshold mechanical stimuli elicited discrete hindlimb flinches (allodynia) over a prolonged (>2h) time course. In single-unit recordings from superficial lumbar dorsal horn neurons, low-threshold mechanically evoked responses were significantly enhanced, accompanied by receptive field expansion, following id injection of histamine in histamine-responsive neurons. This was not observed in histamine-insensitive neurons, or following id injection of saline or SLIGRL-NH2, regardless of whether the latter activated the neuron or not. These results suggest that itch-responsive neurons are selectively sensitized by histamine but not SLIGRL-NH2 to account for alloknesis. The presently described "calf" model appears to distinguish between itch- and pain-related behavioral responses, and provides a basis to investigate lumbar spinal neural mechanisms underlying itch, alloknesis, pain and allodynia.

Cross-sensitization of histamine-independent itch in mouse primary sensory neurons

Overexpression of pruritogens and their precursors may contribute to the sensitization of histamine-dependent and -independent itch-signaling pathways in chronic itch. We presently investigated self- and cross-sensitization of scratching behavior elicited by various pruritogens, and their effects on primary sensory neurons. The MrgprC11 agonist BAM8-22 exhibited self- and reciprocal cross-sensitization of scratching evoked by the protease-activated receptor-2 (PAR-2) agonist SLIGRL. The MrgprA3 agonist chloroquine unidirectionally cross-sensitized BAM8-22-evoked scratching. Histamine unidirectionally cross-sensitized scratching evoked by chloroquine and BAM8-22. SLIGRL unidirectionally cross-sensitized scratching evoked by chloroquine. Dorsal root ganglion (DRG) cells responded to various combinations of pruritogens and algogens. Neither chloroquine, BAM8-22 nor histamine had any effect on responses of DRG cell responses to subsequently applied pruritogens, implying that their behavioral self- and cross-sensitization effects are mediated indirectly. SLIGRL unilaterally cross-sensitized responses of DRG cells to chloroquine and BAM8-22, consistent with the behavioral data. These results indicate that unidirectional cross-sensitization of histamine-independent itch-signaling pathways might occur at a peripheral site through PAR-2. PAR-2 expressed in pruriceptive nerve endings is a potential target to reduce sensitization associated with chronic itch.

Molecular epidemiology of Mycobacterium tuberculosis in an urban area in Japan, 2002-2006

SETTING

Shinjuku City, Tokyo, Japan.

OBJECTIVE

To evaluate the status of transmission of Mycobacterium tuberculosis in Shinjuku City to allocate resources efficiently and effectively for a successful tuberculosis (TB) control programme.

DESIGN

Observational descriptive study combining the genotype data of M. tuberculosis with TB patient profiles.

RESULTS

The genotype clustering rate was significantly higher in males (adjusted odds ratio [aOR] 1.94, 95%CI 1.04-3.65, P = 0.038), patients aged <40 years (aOR 2.09, 95%CI 1.17-3.71, P = 0.012) and the homeless (aOR 2.72, 95%CI 1.42-5.20, P = 0.002), and was lower for the foreign-born (aOR 0.21, 95%CI 0.06-0.76, P = 0.017). Among 45 genotype clusters containing 152 TB patients, 26 clusters containing 102 patients (67.1%) were composed of a mix of homeless and non-homeless patients. One of the mixed clusters included an 8-month-old infant born in Japan.

CONCLUSION

The study revealed that M. tuberculosis transmission occurred more frequently among the homeless than in non-homeless persons. However, transmission by casual contact between the homeless and the general population was also shown to occur.

Effect of fluoride-releasing adhesive system on decalcified dentin

The aim of this study was to evaluate the effect of fluoride-releasing adhesive systems on human decalcified dentin in vitro. Two fluoride-releasing adhesive systems, Reactmer bond (RB, Shofu) and ABF (AF, Kuraray), an experimental system, and a commercial adhesive system without fluoride release, SE bond (SE, Kuraray), were used in this study. The amount of fluoride release from adhesive in deionized water was measured every week for 10 weeks. Class V cavities were prepared on extracted human pre-molars and decalcified dentin was promoted by using a bacterial caries induction system at the cavity floor. The cavities preserving decalcified dentin were restored with resin composite (AP-X, Kuraray) after treatment by each adhesive system. The specimens without treatment by adhesive system and restoration were used for control. The specimens with restoration were then incubated for 4 weeks at 37 degrees C, 100% humidity. Microradiographs of the specimens showed that the radiopacities of the decalcified dentin layers in RB and AF groups with fluoride release were significantly higher than those in SE or control groups without fluoride release. This result suggested that the fluoride-releasing adhesive systems enhanced mineralization of decalcified dentin.

Inhibition of artificial secondary caries by fluoride-releasing adhesives on root dentin

Fluoride-releasing materials can be expected to inhibit the secondary caries. The aim;of this study was to evaluate the effect of fluoride-releasing adhesives on inhibition of secondary caries in outer and wall lesions. Two commercial fluoride-releasing adhesives, Reactmer bond (RB) and One-up bond F (OB), and a commercial adhesive without fluoride release, Mac-bond II (MB), were used prior to placement of restorative materials without fluoride release, Lite-fil II A (LF) and Estelite (EL), and a fluoride-releasing restorative material, Reactmer paste (RP). Class V cavities prepared on extracted human premolars were restored with various combinations of the materials: MB/EL, OB/EL, RB/LF and RB/RP. The restored teeth were incubated in bacterial medium containing sucrose with Streptoccus mutans for 14 days. Microradiographs of specimens showed no wall lesions in all groups and an acid-resistant layer adjacent to the restoration in the caries-like lesion. OB/EL, RB/LF and RB/RP groups showed thicker layers than the MB/EL group. The RB/RP group formed the shallowest outer lesion among all groups. These results indicate that fluoride-releasing adhesives are effective in the prevention of wall lesions but exhibit little outer lesion inhibition. Therefore, combined restoration using a fluoride-releasing adhesive and fluoride-releasing restorative material should be selected to inhibit secondary caries.

Effect of adhesives on the inhibition of secondary caries around compomer restorations

This study evaluated the effect of adhesives on the inhibition of secondary caries around compomer restorations in vitro. Two adhesive systems with a Bis-GMA resin, Scotch bond Multi-purpose (MP) and Single Bond (SB), and one adhesive system with no Bis-GMA resin, F2000 compomer primer/adhesive (PA), were used prior to placement of the compomer (F2000), and non-fluoride releasing resin composite (Z100) was used as a control. Class V cavities prepared on extracted human premolars were restored with various combinations of materials: F2000/MP, F2000/SB, F2000/PA, Z100/MP, Z100/SB and Z100/PA. The restored teeth were incubated in bacterial medium containing sucrose with Streptococcus mutans for two weeks after storage for 14 days. On microradiographs, the radio-opaque layers adjacent to the F2000 restorations were thick and clear, while the layers in the Z100 restorations were unclear. In the F2000 restorations, the mean thickness of the radio-opaque layers in the PA group was significantly greater than that of the MP and SB groups. In fluoride-releasing measurement, F2000 coated with PA showed a significantly higher amount of fluoride release than MP and SB, and no significant difference in the amount of fluoride release from uncoated F2000. These results indicated that applying an adhesive without Bis-GMA resin to compomer restoration has no suppressive effect on the fluoride release from compomer and might be beneficial for inhibiting secondary caries in vitro.

Inhibition of artificial secondary caries in root by fluoride-releasing restorative materials

This investigation evaluated the fluoride-releasing properties of various fluoride-releasing restorative materials, including resin-modified glass-ionomer cements (Fuji ionomer TypeII LC, Photac-Fil Aplicap, Vitremer), compomers (Ionosit FIL, Compoglass, Dyract) and fluoride-releasing resin composites (Heliomolar radiopaque, Degufill mineral). The study also estimated the effects of those materials on the inhibition of artificial secondary caries around restorations using a bacterial caries-inducing system. The amount of fluoride released from the materials in deionized water was measured every one week for 10 weeks. Class V cavities with the gingival margin located in the root were prepared in extracted human premolars and restored with each of the materials. The restored teeth were incubated in the bacterial artificial caries chamber, and the artificial lesion created around the restoration was observed microradiographically. The resin-modified glass-ionomer cements released the largest amount of fluoride and created a thick radio-opaque zone in the artificial lesion along the restoration-dentin interface. These results indicated that the fluoride-releasing restorative materials have the potential to inhibit secondary caries formation around restorations. Resin-modified glass-ionomer cements presented a particularly strong effect, compared with compomers and fluoride-releasing resin composites.

In vivo receptor labeling of peripheral benzodiazepine receptor by ex vivo binding of [3H]PK11195

In vivo receptor labeling of the peripheral benzodiazepine receptor was investigated using ex vivo binding of [3H]-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline-carb ox-amide ([3H]PK11195). In autoradiographic studies, high level specific binding of [3H]PK11195 was observed in the olfactory bulb. Intravenous administration of PK11195 dose-dependently (0.03-3 mg/kg) inhibited ex vivo binding of [3H]PK11195 in the olfactory bulb. Likewise, N-(2,5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide (DAA1106), a newly identified peripheral benzodiazepine receptor-specific ligand, dose-dependently (0.1-100 mg/kg) reduced ex vivo binding of [3H]PK11195, when administered intraperitoneally. In contrast, clonazepam, a central benzodiazepine receptor-specific agonist, had negligible effects on ex vivo binding of [3H]PK11195. We propose that the ex vivo receptor binding technique we used will facilitate determination of in vivo receptor occupancy of the peripheral benzodiazepine receptor.

The role of the UL41 gene of herpes simplex virus type 1 in evasion of non-specific host defence mechanisms during primary infection

The UL41 gene product (vhs) of herpes simplex virus (HSV) is packaged in the virion, and mediates host protein synthesis shutoff at the early stage of the virus replication cycle. In order to clarify the role of vhs in virus replication and virulence, we isolated a completely UL41-deficient mutant (the VRDelta41 strain) and its revertant (the VRDelta41R strain). In the mouse encephalitis model, the replication of strain VRDelta41 was inhibited after 2 days post-infection, resulting in low virulence, by gamma-ray-sensitive cells such as lymphocytes and/or neutrophils. The result suggested that some cytokines, produced in VRDelta41-inoculated brains, activate and induce the migration of gamma-ray-sensitive cells to the infection site. Therefore, cytokines produced by HSV-1-infected human cells were screened, and potent inductions of interleukin (IL)-1beta, IL-8 and macrophage inflammatory protein-1alpha by VRDelta41 infection were observed. Moreover, the VRDelta41 strain showed 20- and 5-fold higher sensitivity to interferon-alpha and -beta compared to the wild-type strain, respectively. These results indicate that one important role of vhs in vivo is evasion from non-specific host defence mechanisms during primary infection through suppression of cytokine production in HSV-infected cells and reduction of the anti-HSV activity of interferon-alpha and -beta.

Comparison of polymorphism of thymidine kinase gene and restriction fragment length polymorphism of genomic DNA in herpes simplex virus type 1

The polymorphism of the thymidine kinase (TK) gene of herpes simplex virus type 1 (HSV-1) was analyzed and was compared with the restriction fragment length polymorphism (RFLP) of the whole genome to evaluate the relative efficiency of the TK gene as a potential probe for identification and discrimination of HSV-1. The effectiveness of using the polymorphism of the TK gene in classifying HSV-1 strains was comparable to that of RFLP analysis of 66 sites, suggesting that TK gene sequencing may have important applications in epidemiological studies of HSV-1.

[The role of daunorubicin in induction therapy for adult acute myeloid leukemia]

The relationship between the total dose of daunorubicin (DNR) in induction therapy and the treatment outcome were evaluated based upon individualized doses of DNR during induction therapy for patients with acute myeloid leukemia(AML). Ninety-two previously untreated adult AML patients admitted to our hospital were analyzed for the dose of DNR required for complete remission (CR), the CR rate, disease-free survival (DFS) and overall survival (OS). The induction therapy consisted of DNR (40 mg/m2/d, i.v., from D 1 until the marrow was hypoplastic), Ara-C, prednisolone, and/or 6-thioguanine. Eighty-three out of 92 patients were assessable. Sixty-three patients entered CR (76%), of whom 52 attained CR with the first course of induction therapy. The 10-year DFS and OS rates were 31.2% and 42.3%, respectively. The median total dose of DNR in the induction therapy was 280 mg/m2 (120-480 mg/m2), which was not influenced by initial WBC count, or FAB type. These results indicate that when the dose is linked to the observed tumor response, the optimal dose of DNR in the induction therapy is around 280 mg/m2 (40 mg/m2 x 7 times), which is higher than the conventional dose of 40-60 mg/m2 for 3 days. The higher dose of DNR in the induction therapy for adult AML should be selected when the feasibility of a new drug is evaluated in a randomized trial.

Rapid phenotypic characterization method for herpes simplex virus and Varicella-Zoster virus thymidine kinases to screen for acyclovir-resistant viral infection

A rapid phenotypic screening method for herpes simplex virus (HSV) and varicella-zoster virus (VZV) thymidine kinase (TK) genes was developed for monitoring acyclovir-resistant viruses. This method determines the biochemical phenotype of the TK polypeptide, which is synthesized in vitro from viral DNA using a procedure as follows. The TK gene of each sample virus strain is amplified and isolated under the control of a T7 promoter by PCR. The PCR products are transcribed with T7 RNA polymerase and translated in a rabbit reticulocyte lysate. Using this method, enzymatic characteristics and the size of the TK polypeptides encoding HSV and VZV DNA were defined in less than 2 days without virus isolation. The assay should be a powerful tool in monitoring drug-resistant viruses, especially in cases in which virus isolation is difficult.

[A study on stress processes for college students during semester-end examinations]

The present study examined individual differences in psychological and physiological stress responses to the same stressor. In Study 1, psychological stress responses were assessed at three time periods: four weeks before, the day before, and the middle day of the semester-end examination period (N = 69). Both stress coping and MPI were assessed once during the study. In Study 2, 15 subjects were exposed to the same psychological stressor in an experiment to measure heart rate. The stressors were memorization of material relevant to the examination (Test 1), and mental calculation irrelevant to the examination (Test 2). Subjects were divided into 2 groups on the basis of their Study 1 psychological stress response scores: the low stress group (LS, N = 10) and the high stress group (HS, N = 5). The results of Study 1 and Test 1 of Study 2 suggested that there were significant differences between LS and HS in stress responses. These findings were discussed in light of cognitive appraisal and controllability of time. Further studies are needed to clarify the aspect of time span in cognitive appraisal.

Release and recharge of fluoride by restorative materials

This study investigated the release and recharge of fluoride by restorative materials. Resin-modified glass ionomers (RGIs), polyacid-modified composite resins (PMCRs) and resin composite containing fluoride were used for comparison of fluoride release. Non-fluoride-releasing resin composite was used as a control. The amounts of fluoride release from RGIs and PMCRs remarkably increased in the citrate-phosphate acid buffer compared with distilled water. The amounts of fluoride recharged in RGIs increased with the concentration of NaF solution, but those of PMCRs exposed to all concentrations of NaF solutions were less than 1.5 ppm. Neither resin composite containing fluoride and non-fluoride-releasing resin composite gave any evidence of recharge. RGIs and PMCRs affected by acid buffer solution could not recharge much fluoride even if they were immersed in the 1000 ppmF NaF solution. The results suggested that the matrix of RGIs and PMCRs functioned as a reservoir of fluoride, but the functions were lost by acid attack.

Influence of filler content and gap dimension on wear resistance of resin composite luting cements around a CAD/CAM ceramic inlay restoration

We investigated the influence of filler content and gap dimension on the wear resistance of composite luting cement around CAD/CAM ceramic inlay restorations. Experimental hybrid dual-cured composite luting cements containing 60, 70, 72, 74 and 80 wt% of silanated barium-silica fillers were used for cementing CAD/CAM ceramic inlay into the cavity. The specimens involving inlay-cement-tooth interfaces were subjected to a three-body wear test. The relation between the interfacial gap dimension and wear loss was also investigated using 60, 70 and 80 wt% filled cements. The cements containing more than 70 wt% filler presented significantly higher wear resistance than 60 wt% filled cement. There was a positive linear relationship between gap dimension and wear loss, and the inclination of the regression line decreased with increasing filler content. These results indicated that the higher filler content of the cement increased the wear resistance and this desirable influence appeared more remarkably in the wider horizontal gap dimension.

A selective dopamine D4 receptor antagonist, NRA0160: a preclinical neuropharmacological profile

NRA0160, 5 - [2- ( 4- ( 3 - fluorobenzylidene) piperidin-1-yl) ethyl] - 4 -(4-fluorophenyl) thiazole-2-carboxamide, has a high affinity for human cloned dopamine D4.2, D4.4 and D4.7 receptors, with Ki values of 0.5, 0.9 and 2.7 nM, respectively. NRA0160 is over 20,000fold more potent at the dopamine D4.2 receptor compared with the human cloned dopamine D2L receptor. NRA0160 has negligible affinity for the human cloned dopamine D3 receptor (Ki=39 nM), rat serotonin (5-HT)2A receptors (Ki=180 nM) and rat alpha1 adrenoceptor (Ki=237 nM). NRA0160 and clozapine antagonized locomotor hyperactivity induced by methamphetamine (MAP) in mice. NRA0160 and clozapine antagonized MAP-induced stereotyped behavior in mice, although their effects did not exceed 50% inhibition, even at the highest dose given. NRA0160 and clozapine significantly induced catalepsy in rats, although their effects did not exceed 50% induction even at the highest dose given. NRA0160 and clozapine significantly reversed the disruption of prepulse inhibition (PPI) in rats produced by apomorphine. NRA0160 and clozapine significantly shortened the phencyclidine (PCP)-induced prolonged swimming latency in rats in a water maze task. These findings suggest that NRA0160 may have unique antipsychotic activities without the liability of motor side effects typical of classical antipsychotics.

Nucleotide sequence of thymidine kinase gene of sequential acyclovir-resistant herpes simplex virus type 1 isolates recovered from a child with Wiskott-Aldrich syndrome: evidence for reactivation of acyclovir-resistant herpes simplex virus

Recurrent acyclovir (ACV)-resistant (ACV-r) herpes simplex virus type 1 (HSV-1) infections occurred in a patient with Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency syndrome composed of three clinical characteristics of immunodeficiency, thrombocytopenia, and an eczematous dermatitis. The patient had severe and recurrent ACV-r herpes simplex and was treated with vidarabine in a satisfactory manner from 1993 to 1997. During the 4-year observation period, two ACV-sensitive (ACV-s) HSV-1 isolates and five ACV-r HSV-1 isolates were recovered. The nucleotide sequence of the thymidine kinase (TK) gene from these sequential ACV-r isolates was compared with the ACV-s isolates. A single nucleotide deletion of cytosine (C) from homopolymer stretch of four C residues between nucleotide 1061 and 1064 of the open reading frame was found in all ACV-r isolates. No other differences were observed in the TK nucleotide sequence between ACV-s and ACV-r isolates. The TK nucleotide sequences of the two ACV-s isolates were identical to each other and those of the five ACV-r isolates were identical to one another. These results suggest that the ACV-r HSV-1 might have derived from the ACV-s strain in the patient body and that TK-associated ACV-r HSV-1 can reactivate from latency.

In vivo receptor occupancy of NRA0045, a putative atypical antipsychotic, in rats

We have previously reported that (R)-(+)-2-amino-4-(4-fluorophenyl)-5-[1-[4-(4-fluorophenyl)-4-oxobutyl]+ ++pyrrolidin-3-yl]thiazole (NRA0045) is a novel antipsychotic agent with affinities for dopamine D4, 5-hydroxytryptamine 2A (5-HT2A) and alpha1 receptors. In the present study, in vivo receptor occupancy of 5-HT2A, alpha1, dopamine D2 and D3 receptors by NRA0045 was assessed, based on in vivo and ex vivo receptor binding, and findings were compared to reference antipsychotic drugs (haloperidol, risperidone, clozapine). Intraperitoneal administration of haloperidol highly occupied the dopamine D2 receptor in the striatum and nucleus accumbens, and alpha1 adrenoceptors in the frontal cortex. Occupation of the 5-HT2A receptor in the frontal cortex and the dopamine D3 receptor in the nucleus accumbens and islands of Cajella was moderate. By contrast, atypical antipsychotics such as risperidone and clozapine dose-dependently occupied the 5-HT2A receptor in the frontal cortex, with moderate to negligible occupancy of the D2 receptor in the striatum and the nucleus accumbens. Clozapine and risperidone also occupied the alpha1 adrenoceptor in the frontal cortex, and clozapine did not occupy the dopamine D3 receptor. As seen with other atypical antipsychotics, intraperitoneal administration of NRA0045 dose-dependently occupied the 5-HT2A receptor and the alpha1 adrenoceptor in the frontal cortex, while it was without effect on dopamine D2 and D3 receptors in the striatum, nucleus accumbens and islands of Cajella. Thus, the strong occupancy of 5-HT2A and alpha1 receptors is involved in the pharmacological action of NRA0045.

Neuropharmacological profile of peripheral benzodiazepine receptor agonists, DAA1097 and DAA1106

Receptor binding and behavioral profiles of N-(4-chloro-2-phenoxyphenyl)-N-(2-isopropoxybenzyl)acetamide (DAA1097) and N-(2,5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide (DAA1106), novel, selective agonists for the peripheral benzodiazepine receptor (PBR) were examined. DAA1097 and DAA1106 inhibited [3H]PK 11195 binding to crude mitochondrial preparations of rat whole brain, with IC50 values of 0.92 and 0.28 nM. Likewise, DAA1097 and DAA1106 inhibited [3H]Ro 5-4864 binding to the same mitochondrial preparation, with IC50 values of 0.64 and 0.21 nM. In contrast, DAA1097 and DAA1106 did not inhibit [3H]-flunitrazepam, the central benzodiazepine receptor (CBR) ligand, binding to membranes of rat whole brain (IC50>10,000nM). Oral administration of DAA1097 and DAA1106 had anxiolytic effects in the mouse light/dark exploration test and in the rat elevated plus- maze test. Oral administration of DAA1106, diazepam and buspirone but not DAA1097 significantly increased sleeping time in hexobarbital-induced anesthesia in mice. The order of potency of potentiation of hexobarbital anesthesia was diazepam> buspirone> DAA1106> DAA1097. Oral administration of DAA1097 and DAA1106 but not diazepam and buspirone did not affect spontaneous locomotor activity in mice. These findings indicate that DAA1097 and DAA1106 are PBR selective ligands with potent anxiolytic-like properties, in laboratory animals.

Binding characteristics of [3H]DAA1106, a novel and selective ligand for peripheral benzodiazepine receptors

Here, we investigated the binding characteristics of [3H]N-(2,5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide ([3H]DAA1106), a potent and selective ligand for peripheral benzodiazepine receptors, in mitochondrial fractions of the rat brain. [3H]DAA1106 bound to the mitochondrial fraction of the rat brain in a saturable manner. The dissociation constant (Kd) and maximal number of binding sites (Bmax) obtained from Scatchard plot analysis of the saturation curve of [3H]DAA1106 binding were 0.12 +/- 0.03 nM and 161.03 +/- 5.80 fmol/mg protein, respectively. [3H]DAA1106 binding to mitochondrial preparations of the rat cerebral cortex was inhibited by several peripheral benzodiapine receptor ligands, and DAA1106 was the most potent inhibitor in inhibiting [3H]DAA1106 binding among the peripheral benzodiazepine receptor ligands we tested. The binding of [3H]DAA1106 was not affected by several neurotransmitter-related compounds, including adrenoceptor, gamma-aminobutyric acid (GABA), dopamine, 5-hydroxytryptamine (5-HT), acetylcholine, histamine, glutamate and central benzodiazepine receptor ligands even at a concentration of 10 microM. In the cerebral cortex of rhesus monkeys, DAA1106 and 1-(2-chlorophenyl)-N-methyl-(1-methylpropyl)-3-isoquinoline carboxamide (PK11195) potently inhibited [3H]DAA1106 binding, while 7-chloro-5-(4-chlorophenyl)-1-methyl-1,3-dihydrobenzo[e][1,4]diazepin -2-one (Ro5-4864) did not. The highest [3H]DAA1106 binding was observed in the olfactory bulb, followed by the cerebellum. In autoradiographic studies, practically the same results were obtained, in that the highest binding of [3H]DAA1106 was in the olfactory bulb. Potent labeling was also noted in ventricular structures such as the choroid plexus. Thus, [3H]DAA1106 is a potent and selective ligand for peripheral benzodiazepine receptors and should prove useful for elucidating the physiological relevance of events mediated through peripheral benzodiazepine receptors.

Inhibition of carious lesions in vitro around gallium alloy restorations by fluoride releasing resin-ionomer cement

A new fluoride releasing resin-ionomer cement was used for bonding of gallium alloy restorations in vitro. Etching, priming, and fluoride releasing resin-ionomer cement were used in the experimental group (ARG), prior to placement of the gallium alloy restorations. Three different controls were used: gallium alloy only (G), no etching, fluoride releasing resin-ionomer cement, gallium alloy (RG), etching, priming, non-fluoride cement and gallium alloy (ACG). The mean shear bond strengths of ARG group to enamel and dentin were higher than those of the three control groups. Artificial secondary caries lesions around the restorations in the experimental group and the control groups were produced, using a strep. mutans culture. The microradiographs were examined for presence of a caries inhibition zone near the restoration. Caries inhibition zones were clearly detected around RG and ARG, but not around G and ACG. The results indicate that the fluoride releasing resin-ionomer cement provided good adhesion and caries inhibition in enamel and dentin.

[Two cases of functioning parathyroid cysts]

Two cases of functioning cysts are reported. The first patient was a 48-year-old man who underwent percutaneous cyst puncture for a palpable mass in the neck at another hospital. Hypercalcemic crisis brought the patient to Koga General Hospital. The second patient was a 69-year-old woman with the complaint of discomfort in the right neck of several years duration and with a palpable mass identified on physical examination at a local hospital. Both patients had high serum calcium and parathyroid hormone (PTH) levels and were diagnosed as having functioning parathyroid cysts by imaging studies including ultrasonography, computed tomographic scan, magnetic resonance imaging and scintigraphy. After parathyroidectomy, their serum calcium and PTH levels became normal, but calcium supplement was necessary in the first patient. To our knowledge, these are the 40th and 41st cases reported in the Japanese literature.

[Prognostic significance of CD7 expression in adult acute myeloid leukemia]

To evaluate the prognostic significance of CD7 expression in de novo acute myeloid leukemia (AML), we studied 63 patients with AML who had been admitted to our hospital between September 1989 and January 1996. Even of the patients were later eliminated from the study (9 due to insufficient surface marker analyses, and 2 due to early death). The remaining 52 patients (median age: 42.5 years) were evaluated for morphologic subtype, immunophenotypic classification, complete remission (CR), disease-free survival (DFS) and overall survival (OS). All 52 patients were grouped by the French-American-British classification system: 10 as M1, 16 as M2, 11 as M3, 8 as M4, 5 as M5, and 2 as M6. Ten of the patients expressed CD7 on their leukemia cells (positive rate > or = 25) and were classified as CD7(+)AML, with morphological subtypes as follows: 3 as M1, 6 as M2, and 1 as M3. Thirty-three of the 42 patients with CD7 + AML (78.6%) and 6 of the 10 patients with CD7 + AML (40%) achieved CR. DFS and OS rates for the patients with CD7(+)AML were 22.1% and 35.4%, respectively; those for the CD7(+)AML patients were 53.3% and 44.4%, respectively. No significant differences in gender hematological findings, clinical manifestations such as hepatosplenomegaly, lymphadenopathy, or incidence of central nervous system involvement, CR rate, and DFS distinguished patients with CD7(+)AML from those with CD7(+)AML. These suggest that CD7 expression is unlikely to be a prognostic factor in AML.

Role of daunorubicin in the induction therapy for adult acute myeloid leukemia

PURPOSE

To evaluate the relationship of total-dose of daunorubicin (DNR) to the induction therapy and treatment outcome, we have administered individualized doses of DNR during induction treatment to patients with acute myelogenous leukemia (AML).

PATIENTS AND METHODS

Ninety-two previously untreated adult patients with AML who entered our hospital were analyzed for the dose of DNR required to achieve complete remission (CR), the CR rate, disease-free survival (DFS), and overall survival (OS). Induction therapy consisted of DNR 40 mg/m2 daily intravenously from day 1 until the marrow was hypoplastic, cytarabine (Ara-C), prednisolone (PRD), and/or 6-thioguanine (6-TG).

RESULTS

Eighty-three of 92 patients with adult AML were assessable for this study. Sixty-three (76%) patients achieved CR. Fifty-two of 63 CR patients achieved the CR in the first course of induction therapy, and 11 patients required the second course of induction therapy. The 5-year and 10-year DFS rates were 31.2% and 5-year and 10-year OS rates were 45.1% and 42.3%, respectively. The median total dose of DNR in the induction therapy was 280 mg/m2 (120 to 480 mg/m2). DNR dose did not influence the response to therapy and was not influenced by the initial WBC count or French-American-British (FAB) system classification.

CONCLUSION

These results indicated that when the dose was linked to observed tumor response, the optimal dose of DNR in the induction therapy was approximately 280 mg/m2 (40 mg/m2 for 7 days), which is greater than the conventional dose of 40 to 60 mg/m2 for 3 days.

[EPOCH therapy for relapsed/refractory lymphoid malignancies]

Patients with refractory or relapsed non-Hodgkin's lymphoma (NHL), acute T-cell leukemia (ATL), ATL lymphoma and acute lymphocytic leukemia (ALL) received EPOCH therapy. All were previously treated with doxorubicin (DOX), vincristine (VCR) and other drugs. The EPOCH treatment schedule is consisted with DOX (10 mg/M2/day, 5 days c.i.v.), VCR (0.4 mg/M2/day, 4 days c.i.v.), etoposide (50 mg/M2/day, 4 days c.i.v.), cyclophosphamide (750 mg/M2/day, day 6 i.v.) and prednisolone (60 mg/M2/day, 5 days p.o.). Twenty-one patients (ALL:10, NHL:8, ATLL:2, ATL:1) were assessable for response and toxicity. Two patients with ALL and NHL, respectively, achieved a complete remission and 3 patients obtained partial remission (NHL:2, ATLL:1). The hematological toxicity (grade > 1) included neutoropenia, anemia and thrombocytopenia, which were observed in 83.3%, 76.7% and 76.7% respectively, of total 30 EPOCH courses. The major non-hematological toxicities were nausea/vomiting, constipation and infection, but most of the toxicity were tolerable with sufficient clinical supportive care. These results indicate that continuous infusion of DOX, VCR and ETP might be effective in patients who were treated with, and presumed to be resistant to the same drugs administrated by bolus infusion.

An association study between the Cys311 variant of dopamine D2 receptor gene and schizophrenia in the Okinawan population

Neuroleptic drugs have a high affinity for the dopamine D2 receptor (DRD2); therefore DRD2 is thought to be a candidate gene for schizophrenia. Arinami et al. have reported a positive association between schizophrenia and the Cys311 variant of the DRD2 gene. We determined the allele frequency of this polymorphism in 78 Okinawan schizophrenic patients and 112 control subjects. The patients and controls did not differ significantly in allele frequencies of Cys311.

Effect of resin-modified glass ionomer cements on secondary caries

PURPOSE

To evaluate the in vitro secondary caries inhibitory effect of two resin-modified glass ionomer cements (R-GICs).

MATERIALS AND METHODS

Class V cavities were prepared at the cementoenamel junction on facial and lingual surfaces of 32 extracted upper premolars. The facial cavities were restored with a conventional glass ionomer cement (GIC) (Fuji II), while the lingual cavities were restored with either one of the R-GICs (Fuji II LC, Photac Fil, Vitremer), or a resin composite (Z-100). The margins of the restorations were subjected to a 20-day in vitro cariogenic challenge and the degree of demineralization was analyzed by microradiography. The amounts of fluoride released into distilled water from disc specimens of the materials tested were also measured for immersion time up to 161 days.

RESULTS

The R-GICs and GIC's released similar cumulative amounts of fluoride over 161 days. Photac-Fil showed significantly higher amounts of fluoride release over the same period. The depth of the outer lesion and the thickness of the acid-resistant layer showed no significant difference among the R-GICs and GIC's. Moreover, the residual fluoride and calcium in the dentin adjacent to the R-GICs and GIC's were correlated with the thickness of acid-resistant layers in the dentin adjacent to the R-GICs and GIC's by electron probe microanalysis. However, the inhibitory effect of the R-GICs was not directly related to the fluoride concentrations eluted from them.

In vitro and in vivo characterization of the dopamine D4 receptor, serotonin 5-HT2A receptor and alpha-1 adrenoceptor antagonist (R)-(+)-2-amino-4-(4-fluorophenyl)-5-[1-[4-(4-fluorophenyl)-4-oxobutyl] pyrrolidin-3-yl]thiazole (NRA0045)

(R)-(+)-2-Amino-4-(4-fluorophenyl)-5-[1-[4-(4-fluorophenyl)-4-oxobutyl]+ ++pyrrolidin-3-yl]thiazole (NRA0045), a novel thiazole derivative, has high affinities for the human cloned dopamine D4.2, D4.4 and D4.7 receptors, with Ki values of 2.54, 0.55 and 0.54 nM, respectively. NRA0045 is approximately 91-fold more potent at the dopamine D4.2 receptor, compared with human cloned dopamine D2L receptor. NRA0045 also has high affinities for the serotonin (5-HT)2A receptor (Ki = 1.92 nM) and alpha-1 adrenoceptor (Ki = 1.40 nM) but weak affinities (IC50 values are approximately 1 microM) for six other neurotransmitter receptors (adenosine1, 5-HT1A, 5-HT1C, dopamine transporter, alpha2A and alpha2A) and negligible affinities (IC50 values are over 10(-5) M) for 42 other receptors, including neurotransmitters and hormones, ion channels and second messenger systems. Locomotor hyperactivity induced by methamphetamine (1 mg/kg i.p.) in mice was dose-dependently antagonized by NRA0045 (ED50 = 0.5 mg/kg i.p. and 1.9 mg/kg p.o., respectively). Methamphetamine (10 mg/kg i.p.)-induced stereotyped behavior in mice was dose-dependently antagonized by NRA0045, whereas NRA0045 did not exceed 50% inhibition even at the highest dose given (30 mg/kg i.p.). Catalepsy was dose-dependently and significantly induced by NRA0045 in rats, whereas NRA0045 did not exceed 50% induction even at the highest dose given (30 mg/kg i.p.). Thus NRA0045 blocks behaviors associated with activation of the mesolimbic/mesocortical dopaminergic neurons more selectively than behaviors associated with nigrostriatal dopaminergic neurons. In rats, tryptamine-induced clonic seizure, a 5-HT2 receptor-mediated behavior, was also dose-dependently inhibited by NRA0045 (ED50 = 1.7 mg/kg i.p.). Norepinephrine-induced lethality is regarded as being induced through the alpha-1 adrenoceptor. NRA0045 dose-dependently antagonized norepinephrine-induced lethality in rats (ED50 = 0.2 mg/kg i.p.). Thus NRA0045 may have a unique antipsychotic activity with regard to dopamine D4 and 5-HT2A receptors and alpha-1 adrenoceptor antagonistic activities, without producing the extrapyramidal side effects.

The atypical antipsychotic profile of NRA0045, a novel dopamine D4 and 5-hydroxytryptamine2A receptor antagonist, in rats

1. The atypical antipsychotic profile of (R)-(+)-2-amino-4-(4-fluorophenyl)-5-[1-[4-(4-fluorophenyl)-4-oxobutyl] pyrrolidin-3-yl] thiazole (NRA0045), a potent dopamine D4 and 5-hydroxytryptamine (5-HT)2A receptor antagonist, was examined in rats. 2. Spontaneous locomotor activity was decreased dose-dependently with i.p. administration of clozapine (ED50 3.7 mg kg-1), haloperidol (ED50 0.1 mg kg-1) and chlorpromazine (ED50 0.9 mg kg-1), whereas inhibition of this type of behaviour induced by i.p. administration of NRA0045, at doses up to 10 mg kg-1, did not exceed 50%. 3. Locomotor hyperactivity induced by methamphetamine (MAP, 2 mg kg-1, i.p.) in rats (a model of antipsychotic activity) was dose-dependently antagonized by NRA0045 (ED50 0.4 mg kg-1, i.p., and 0.3 mg kg-1, p.o., respectively), clozapine (ED50 0.3 mg kg-1, i.p. and 0.8 mg kg-1, p.o., respectively), haloperidol (ED50 0.02 mg kg-1, i.p. and 0.1 mg kg-1, p.o., respectively), chlorpromazine (ED50 0.3 mg kg-1, i.p. and 3.3 mg kg-1, p.o., respectively). In contrast, the MAP (3 mg kg-1, i.v.)-induced stereotyped behaviour in rats (a model of extrapyramidal symptoms) was not affected by NRA0045 or clozapine, at the highest dose given (30 mg kg-1, i.p.). Haloperidol (ED50 0.3 mg kg-1, i.p.) and chlorpromazine (ED50 4.8 mg kg-1, i.p.) strongly blocked the MAP-induced stereotyped behaviour. NRA0045 and clozapine selectively blocked behaviour associated with activation of the mesolimbic/mesocortical dopamine neurones rather than nigrostriatal dopamine neurones. 4. Extracellular single-unit recording studies demonstrated that MAP (1 mg kg-1, i.v.) decreased the firing rate in the substantia nigra (A9) and ventral tegmental area (A10) dopamine neurones in anaesthetized rats. NRA0045 completely reversed the inhibitory effects of MAP on A10 dopamine neurones (ED50 0.1 mg kg-1, i.v.), whereas the inhibitory effects of MAP on A9 dopamine neurones were not affected by NRA0045, in doses up to 1 mg kg-1 (i.v.). Clozapine completely reversed the inhibitory effects of MAP on A10 dopamine neurones (ED50 1.9 mg kg-1, i.v.) and on A9 dopamine neurones (ED50 2.5 mg kg-1, i.v.). Haloperidol completely reversed the inhibitory effects of MAP on A10 (ED50 0.03 mg kg-1, i.v.) and on A9 dopamine neurones (0.02 mg kg-1, i.v.). NRA0045, like clozapine, was more potent in reversing the effects of MAP on A10 than A9 dopamine neurones. 5. Prepulse inhibition (PPI) is impaired markedly in humans with schizophrenia. The disruption of PPI in rats by apomorphine (0.5 mg kg-1, s.c.) was reversed significantly by NRA0045 (3 mg kg-1, i.p.), clozapine (3 mg kg-1, i.p.) and haloperidol (0.3 mg kg-1, i.p.). 6. Phencyclidine (PCP) elicits predominantly psychotic symptoms in normal humans and in schizophrenics. NRA0045 (0.03-0.3 mg kg-1, i.p.) and clozapine (0.1-1 mg kg-1, i.p.) significantly and dose-dependently shortened the PCP(1.25 mg kg-1, i.p.)-induced prolonged swimming latency in rats in a water maze task, whereas haloperidol (0.01-0.1 mg kg-1, i.p.) did not significantly alter swimming latency. 7. These findings suggest that NRA0045 may have unique antipsychotic activities without the liability of motor side effects typical of classical antipsychotics.

Suppression of oncogenic Ras by mutant neurofibromatosis type 1 genes with single amino acid substitutions

NF1 was first identified as the gene responsible for the pathogenesis of the human genetic disorder neurofibromatosis type 1. cDNA cloning revealed that its putative protein product has a domain showing significant sequence homology with the mammalian Ras GTPase activating protein and two yeast Saccharomyces cerevisiae proteins, Ira1 and Ira2. The Ras GTPase activating protein-related domain of the NF1 gene product (NF1-GRD) stimulates GTPase activity of normal Ras proteins but not of oncogenic mutant Ras from both mammalian and yeast cells. Thus, in yeast, NF1-GRD can suppress the heat-shock-sensitive phenotype of ira- cells but not the same phenotype of activated RAS such as RAS2Val19 and RAS2Leu68. We have screened a pool of mutagenized NF1 expression plasmids and obtained two mutant NF1 cDNA clones that can suppress the heat-shock-sensitive phenotype of RAS2Val19 cells. One clone (NF201) suppressed RAS2Leu68, RAS2Ser41, and RAS2Val19, whereas another clone (NF204) preferentially suppressed RAS2Val19. When expressed in mammalian cells, these mutant NF1-GRDs were able to induce the morphological reversion of v-ras-transformed NIH 3T3 cells. Both wild-type and mutant NF1-GRDs can stimulate the GTPase activity of normal but not transforming Ras. We suggest that mutant NF1-GRDs may bind tightly to transforming Ras, which stays in GTP-bound conformation, thus preventing the interaction with the putative effector molecule. On the other hand, normal Ras cannot be sequestered since the bound GTP is rapidly hydrolyzed upon interaction with mutant NF1-GRD to yield Ras-GDP, which is readily released from the NF1-GRD and recycled.

Chromosomal translocation t(13;16) in a patient with idiopathic hypogonadotropic hypogonadism

A patient with idiopathic hypogonadotropic hypogonadism (IHH) had an apparently balanced reciprocal translocation involving chromosomes 13 and 16 [t(13;16)(q14.11;q24)]. The patient's father has the same chromosomal translocation with no apparent physical abnormalities. The role of the chromosomal translocation in this patient is discussed.

[Studies on factor affecting mother-to-child HTLV-I transmission]

Epidemiological data indicate that breast feeding is the primary route of mother-to-child transmission of HTLV-I. However, serological studies show that 60 to 90% of infants who are fed breast milk from HTLV-I carriers avoid HTLV-I infection. To understand the mechanism of the virus transmission, the titer of HTLV-I antibodies and p40tax antibody and the copy number of the HTLV-I proviral DNA in peripheral lymphocytes in the HTLV-I carrier-mothers were surveyed. The seroprevalence of HTLV-I in the children born to carrier mothers was 6.1% in a normal breast feeding group, 7.7% in a group fed with freeze-thawed breast milk and none in a bottle-fed group. The difference between the seroconversion rate for the normal breast feeding group and others was statistically insignificant. Our studies also indicated that neither the titer of HTLV-I antibodies in carriers nor the duration of breast feeding was relevant to seroconversion in the children. The seroconversion rate in children was higher in p40tax antibody-positive mothers than in a seronegative group, but the difference was statistically insignificant. In conclusion, the copy number of the HTLV-I provirus in the lymphocytes of the carrier mothers was the most relevant factor in the seroconversion of infants who received breast milk from HTLV-I carriers.

A case of Graves' disease associated with Klinefelter's syndrome

Graves' disease was found in a 41-year-old, married male patient with Klinefelter's syndrome. The patient began having finger tremor 5 years previously, and developed palpitation and weight loss 3 months prior to examination. He had a diffuse goiter, exophthalmos, and atrial fibrillation. Plasma levels of T3, T4 and free T4 were 2.8 ng/ml, 16.6 micrograms/dl and 4.5 ng/dl respectively. [123I] uptake was 53%, and TSH receptor antibody was 75%. Although he had no gynecomastia, his general physical appearance was that of typical eunuchoism. Chromosome studies showed a karyotype of 47,XXY. A diagnosis of Graves' disease associated with Klinefelter's syndrome was made.

Paraplegia caused by brown tumor in primary hyperparathyroidism. Case report

A brown tumor is a secondary disorder of bone associated with hyperparathyroidism that arises predominantly in the metacarpals, phalanges, jaw, pelvis, or femur. Rarely does this tumor involve the spine. The authors describe a case of brown tumor in primary hyperparathyroidism, causing spinal cord compression. The first step in diagnosing this lesion in an unusual site is a high index of suspicion. Essentially, this tumor is benign but emergency surgery for tumor removal is recommended in patients showing acute spinal cord compression.

[Influence of thermal cycling on the adhesive strength of adhesive resin cement]

The purpose of this study was to examine the influences of thermal cycling on the adhesive strength of the adhesive resin cements. Four kinds of adhesive resin cements, which belonged to the commercial composite resin inlay products, were used for the study. They were CR Inlay Cement, Duo Cement, Dual Cement and P-30 diluted with Enamel Bond. The shear adhesive strengths to tooth substance and composite resin inlay were measured. Adhesive strength to etched enamel : CR Inlay Cement showed the highest values of 274 kg/cm2 after immersion in water at 37 degrees C for 24 hours and 230 kg/cm2 after 300 thermal cycles at 4 degrees C for 3 min and at 60 degrees C for 3 min. Adhesive strength to etched dentin : P-30 diluted with Enamel Bond showed the highest values of 64 kg/cm2 after 24-hour immersion in water, and 63 kg/cm2 after 300 thermal cycles. Adhesive strength to composite resin inlay : CR Inlay Cement showed the highest values of 310 kg/cm2 after 24-hour immersion in water, 306 kg/cm2 after 300 thermal cycles, and 297 kg/cm2 after 1000 thermal cycles. Adhesive resin cements other than CR Inlay Cement, showed a decrease in adhesive strengths to tooth substance and composite resin inlay after thermal cycling. Especially, Dual Cement and Duo Cement showed considerable decreases.

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in a patient with multiple sclerosis

Association of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) with multiple sclerosis (MG) is very rare, although many other disorder of the nervous system have been reported to be associated with this syndrome; there is only one case report in the literature. We describe here a patient with the syndrome associated with MS. A 62-year-old women had a variety of neurologic symptoms, where clinical course was typical of MS. Transient episodes of hyponatremia and disturbance of consciousness occurred repeatedly with deterioration of MS. The concentration of antidiuretic hormone (ADH) was high whereas the plasma osmolality was low in the presence of concentrated urine, during the episodes of hyponatremia. Urinary Na excretions exceeded 20 mEq/day. Computed tomography and magnetic resonance imaging revealed lesions in the brain, especially in the periventricular region. The hypothalamus and pituitary appeared normal by these imaging methods. Since the periventricular region surrounds and may be functionally connected to the hypothalamus which plays the central role in the regulation of ADH secretion, it was concluded that association of SIADH and MS in this patient was not coincidental, and that demyelinating processes in the periventricular region exerted an abnormal influence on ADH secretion resulting in SIADH. Contribution of other mechanisms as increased intrathoracic pressure, however, could not be excluded completely.