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Accumulation of amyloid β peptides (Aβ) is thought to be one of the causal factors of Alzheimer's disease (AD). The aspartyl protease β-site amyloid precursor protein cleaving enzyme 1 (BACE1) is the rate-limiting protease for Aβ production, and therefore, BACE1 inhibition is a promising therapeutic approach for the treatment of AD. Starting with a dihydro-1,3-thiazine-based lead, Compound J, we discovered atabecestat 1 (JNJ-54861911) as a centrally efficacious BACE1 inhibitor that was advanced into the EARLY Phase 2b/3 clinical trial for the treatment of preclinical AD patients. Compound 1 demonstrated robust and dose-dependent Aβ reduction and showed sufficient safety margins in preclinical models. The potential of reactive metabolite formation was evaluated in a covalent binding study to assess its irreversible binding to human hepatocytes. Unfortunately, the EARLY trial was discontinued due to significant elevation of liver enzymes, and subsequent analysis of the clinical outcomes showed dose-related cognitive worsening.

Firefighters often work in harsh high-temperature and high-humidity environments such as scene of fires. Additionally, the heat and perspiration generated by the human bodies further increase the temperature and humidity inside the fire-protective clothing. The aim of this research is to scientifically evaluate the body load based on vital data from firefighters according to the activities and environment of each firefighter and to further investigate the effect of cooling the human body by fluid intake with the aim of lowering the risk of heatstroke. In a series of experiments, six firefighters took exercise in an environment of 25 and 40 °C as a normal-temperature and a high-temperature condition, respectively. And they took in water or ice slurry before and after exercise. As the experimental result, in case of exercise in the high-temperature environment, intake of ice slurry caused rectal temperature to decrease rapidly compared with intake of water. But in the normal temperature, the cooling effect of rectal temperature by intake of ice slurry showed little difference from ingestion of water. The ear temperature did not show the difference by intake of water and ice slurry both; in addition, after the exercise 1, during rest time with intake of water, the ear temperature decreased to initial temperature at the normal-temperature and high-temperature environment. The trends of cardiac rate looked almost identical between intake of water and ice slurry in each environment for exercise, but after only the exercise 1, intake of ice slurry could decrease cardiac rate to initial condition earlier than intake of water. As a result of this research, ingestion of ice slurry was shown to be effective at reducing the rectal and body surface temperatures during rest after exercise in the high-temperature environment and slowing the heart rate during rest after exercise in both the normal- and the high-temperature environments.

BACE1 inhibitors hold potential as agents in disease-modifying treatment for Alzheimer's disease. BACE2 cleaves the melanocyte protein PMEL in pigment cells of the skin and eye, generating melanin pigments. This role of BACE2 implies that nonselective and chronic inhibition of BACE1 may cause side effects derived from BACE2. Herein, we describe the discovery of potent and selective BACE1 inhibitors using structure-based drug design. We targeted the flap region, where the shape and flexibility differ between these enzymes. Analysis of the cocrystal structures of an initial lead 8 prompted us to incorporate spirocycles followed by its fine-tuning, culminating in highly selective compounds 21 and 22. The structures of 22 bound to BACE1 and BACE2 revealed that a relatively high energetic penalty in the flap of the 22-bound BACE2 structure may cause a loss in BACE2 potency, thereby leading to its high selectivity. These findings and insights should contribute to responding to the challenges in exploring selective BACE1 inhibitors.

Mps1, also known as TTK, is a dual-specificity kinase that regulates the spindle assembly check point. Increased expression levels of Mps1 are observed in cancer cells, and the expression levels correlate well with tumor grade. Such evidence points to selective inhibition of Mps1 as an attractive strategy for cancer therapeutics. Starting from an aminopyridine-based lead 3a that binds to a flipped-peptide conformation at the hinge region in Mps1, elaboration of the aminopyridine scaffold at the 2- and 6-positions led to the discovery of 19c that exhibited no significant inhibition for 287 kinases as well as improved cellular Mps1 and antiproliferative activities in A549 lung carcinoma cells (cellular Mps1 IC₅₀=5.3 nM, A549 IC₅₀=26 nM). A clear correlation between cellular Mps1 and antiproliferative IC₅₀ values indicated that the antiproliferative activity observed in A549 cells would be responsible for the cellular inhibition of Mps1. The X-ray structure of 19c in complex with Mps1 revealed that this compound retains the ability to bind to the peptide flip conformation. Finally, comparative analysis of the X-ray structures of 19c, a deamino analogue 33, and a known Mps1 inhibitor bound to Mps1 provided insights into the unique binding mode at the hinge region.

PURPOSE Many forestry workers who use chain-saws suffer from low back pain. Previous studies have reported that low back pain is related to the working postures while felling a tree with a using chain-saws. However, no previous study has investigated trunk muscle activities during work. The purpose of this study was to clarify the relationship between working postures while holding a chain-saw, and trunk muscles activities as measured by surface electromyography (EMG). METHOD Subjects were 10 males who were not forestry workers. Four task postures while holding a chain-saw were tested: standing, 30(o) trunk flexion, 90(o) trunk flexion and half-kneeling. EMG recordings were obtained bilaterally of the lumbar paraspinal (LP) muscles and rectus abdominis (RA) muscles. Raw EMG data were processed by integrating the EMG and normalizing them to %MVC. The paired t-test was used to detect statistical differences in the activities between the right and left LP muscles and RA muscles. One-factor repeated measures ANOVA was used to compare the bilateral LP and RA muscle activities among the 4 different postures. The significance level was set to less than 5%. RESULTS In the half-kneeling posture, the right LP muscle activity was 14.7% higher than the left LP muscle activity (p

Ischemia-induced hyperactivity is recognized several hours after both common carotid arteries' occlusion for 5 min in Mongolian gerbils, and it continues for at least 7 days. The aim of this study is to investigate the possible mechanisms of this abnormal behavior. Methamphetamine (MAP) (1 and 3 mg /kg) was administered for 7 days and imipramine (IMP) (5 and 10 mg/kg) was administered for 7 or 14 days. Bilateral carotid artery was occluded for 5 min 24 h after the last administrations of these drugs. MAP, which had been administered every day for 1 week, showed marked inhibition in the ischemia-induced hyperactivity. However, IMP did not have any effect even though it had been injected every day for 2 weeks. Hippocampal CA1 neuronal changes also appeared in the MAP- and IMP-administered groups. As the dopaminergic neurotransmission is facilitated by the repeated administration of MAP, the ischemia-induced hyperactivity may be related to abnormalities in dopaminergic function. The participation of the other neurotransmitters is also discussed.

Background Balance training is a common component of rehabilitation after ankle sprains. A relatively high activity of the peroneus longus (PL) to the activity of the tibialis anterior (TA) (a low TA/PL ratio) is reported as an effective muscle activity pattern during balance training to prevent inversion ankle sprains. To date, no research has investigated ankle muscle activity during tilting movements on a wobble board. Objective To assess the magnitude of muscle activity of the ankle while inversion and eversion movements of the ankle joint are performed on a wobble board. Design Single-session randomized repeated-measures study design. Setting University laboratory. Participants Seventeen young adults (11 females and 6 males) with no history of ankle injury. Interventions Participants performed tilting movements on a wobble board in a medial and lateral direction while balancing on their non-dominant leg. The frequency of the movement was set at 40 bpm. Muscle activity of the TA and the PL during five cycles of inversion-eversion movements were collected and stored for analysis. Main Outcome Measurements Normalized RMS EMG values (percentage of each participant9s maximum voluntary isometric contraction; %MVIC) of the TA and PL, along with TA/PL ration in the inversion (wobble board tilted in the lateral direction) and eversion (wobble board tilted in the medial direction) phase. Results There was a significant difference in muscle activity of the PL (inversion phase; 41.6±15.3%MVIC, eversion phase; 59.2±21.5% MVIC, p 0.05). Conclusions The results of the present study indicate that tilting movements on a wobble board in the medial direction (eversion of the ankle joint) may be favorable as an exercise modality after inversion ankle sprains as a high PL activity and a low TA/PL ratio was acquired.

The effects of immobilization stress on anticonvulsant actions and pharmacokinetics of zonisamide were investigated in mice. Oral administrations of zonisamide (10, 20, and 50 mg/kg) dose-dependently reduced incidence of tonic extension (TE) induced by maximal electroshock seizure (MES). Immobilization stress for 2 h immediately after the administration of zonisamide further enhanced the anticonvulsive actions of it. On the other hand, the serum zonisamide concentrations in stressed group were lower during the first 30 min after the administration compared with that in nonstressed control group. Thereafter, there were no significant differences in the serum concentrations between two groups. The brain zonisamide concentration and the concentration ratio of brain/serum at 2 h after administration of zonisamide (50 mg/kg) were significantly higher in stressed group, rather than that in the nonstressed control group without changing the serum concentration. These results suggest that immobilization stress enhances anticonvulsant actions of zonisamide, and that increases of brain zonisamide concentration by immobilization stress may be related with this phenomenon.

Monopolar spindle 1 (Mps1) is essential for centrosome duplication, the spindle assembly check point, and the maintenance of chromosomal instability. Mps1 is highly expressed in cancer cells, and its expression levels correlate with the histological grades of cancers. Thus, selective Mps1 inhibitors offer an attractive opportunity for the development of novel cancer therapies. To design novel Mps1 inhibitors, we utilized the pan-kinase inhibitor anthrapyrazolone (4, SP600125) and its crystal structure bound to JNK1. Our design efforts led to the identification of indazole-based lead 6 with an Mps1 IC50 value of 498 nM. Optimization of the 3- and 6-positions on the indazole core of 6 resulted in 23c with improved Mps1 activity (IC50 = 3.06 nM). Finally, application of structure-based design using the X-ray structure of 23d bound to Mps1 culminated in the discovery of 32a and 32b with improved potency for cellular Mps1 and A549 lung cancer cells. Moreover, 32a and 32b exhibited reasonable selectivities over 120 and 166 kinases, respectively.

The effect of single and chronic methamphetamine (MAP) administration on ischemia-induced hyperactivity was investigated and the mechanism of ischemia-induced hyperactivity was discussed. Ischemia-induced hyperactivity was recognized 3 h after ischemia. However, ischemia-induced hyperactivity at 1 day after ischemia was inhibited when MAP, in a dose of 10 mg/kg, was administered for 7 days and withdrawn for 7 days. It was reported that MAP treatment caused an irreversible decrease in the number of dopamine (DA) uptake sites. In addition to this, monoamine oxidase and the uptake of DA into the nerve terminals are disturbed by cerebral ischemia. Therefore, a lot of DA release happened during and immediately after ischemia, and a marked down-regulation of DA receptor occurred 24 h after ischemia in MAP-injected group. It is conceivable that the DA receptor, especially the presynaptic DA uptake site, is related to the occurrence of ischemia-induced hyperactivity. Further studies appear to be necessary to clarify acceptor susceptibility when neurotransmitters are normalized after transient ischemia.

A method for measurement of rat glomerular fibrinolysis and the results of its application to rat Masugi nephritis are described. The glomerular fibrinolytic activity was measured on isolated glomeruli using a fibrin slide technique. The procedure of this method is simple and the results obtained have a good reproducibility. By applying this method to rat Masugi nephritis, sequential changes in glomerular fibrinolytic activity could be assessed. A decrease in glomerular fibrinolytic activity that was related to the extent of fibrin deposits in the glomeruli was demonstrated in the autologous phase.

A bacterium isolated as resistant to alkyldimethylbenzylammonium chloride (benzalko-nium chloride, BC) and tentatively identified as Enterobacter cloacae, was induced by BC to produce acidic polysaccharide. The optimum concentration of BC for production of the poly-saccharide was 0.1% and the polysaccharide produced amounted to 1.0_??_2.0mg per ml of cul-ture broth. The best carbon and nitrogen sources for the polysaccharide production were glycerol and polypeptone. The acidic polysaccharide was consisted of fucose, galactose, glucose, glucuronic acid, pyruvate, and acetate, like colanic acid. The production of the acidic polysaccharide was not induced by the addition of trimethylbenzylammonium chloride and tetramethylammonium chloride, but it was induced by p-fluorophenylalanine, and the results are discussed.

The cytotoxic activity of tumor necrosis factor (TNF) against L929 fibroblasts in vivo was noncompetitively inhibited by physiological concentrations of glucocorticoids such as hydrocortisone (10(-7) M), corticosterone (5 X 10(-8) M) and dexamethasone (5 X 10(-9) M). The inhibition was abolished by the addition of actinomycin D (0.5 microgram/ml) or cycloheximide (4 microM). A phospholipase A2 inhibitor, quinacrine (2 X 10(-6) M), also inhibited the TNF cytotoxicity. These findings suggest that the antitumor cytotoxic reaction by TNF is regulated by glucocorticoid through some mechanism involving de novo transcription and translation and that this regulatory mechanism may involve inhibition of phospholipase A2 activity.

Four cell lines derived from pure and mixed types of human testicular germ cell tumors in vitro and in nude mice were examined by light and electron microscopies. The NEC8 and NEC15 cell lines in vitro were composed of embryonal carcinoma cells with potentiality of trophoblastic differentiation. All of the tumors formed in nude mice by both cell lines were pure embryonal carcinomas. On the other hand, the NEC14 and ITO-II cell lines showed morphological differentiation from embryonal carcinoma cells to trophoblastic cells and to yolk sac tumor cells in vitro. In nude mice, these cell lines formed mixed tumors which consisted of embryonal carcinoma, yolk sac tumor, immature teratoma or trophoblastic cells. Our data suggest that some embryonal carcinomas have multipotentiality of morphological differentiation but that others have little such potentiality.

In the autologous phase of nephrotoxic nephritis in the rabbit, many round (Type III) cells appeared in the glomerular outgrowth. They had receptors for Fc and C3 and a pronounced phagocytic capacity for carbon. The number of Type III cells in the glomerular outgrowth from rabbits 8 days after injection of nephrotoxic serum (NTS-8) was higher than that of NTS-10 or -15. In contrast, they were rarely observed in the outgrowth of glomeruli from normal and NTS-3 rabbits. The Type II (fusiform) cell, a type of intrinsic glomerular cell, was also increased earlier and more markedly in NTS-8, -10, and -15 than in normal and NTS-3 rabbits.

Four human embryonal carcinoma (EC) cell lines (ITO, NEC 8, NEC 14, NEC 15) derived independently from testicular germ-cell tumors were established in vitro. In their xenografted tumor tissues, all of them exhibited histological characteristics consistent with EC. The cell-biological characterization of these human EC cell lines was investigated with reference to well-known murine EC cell lines. This included examination of their morphology, growth, tumorigenic potential, karyotype, cell-aggregate formation, HLA expression, large glycopeptides, AFP and HCG production, plasminogen-activator secretion, and LDH profiles. Three (ITO, NEC 14, NEC 15) of these human EC cell lines shared cell-biological characteristics consistent with typical EC, but one of them (NEC 8) differed from the others with respect to its rapid growth, high tumorigenic potential, formation of solid cell aggregates, and less differentiated, solid histological pattern. Thus, it is suggested that there are several developmentally different types of human EC cells. The relationship between the properties of these human EC cell lines and their differentiation potential is discussed.

Production of the beta-subunit of human chorionic gonadotropin (beta-hCG) by human germ cell tumors was studied in surgical specimens, cultured cells and xenografted tumors. beta-hCG was identified most frequently in the syncytiotrophoblastic and intermediate trophoblastic components of choriocarcinoma, and it was also detected in syncytiotrophoblastic giant cells, occasionally in association with embryonal carcinoma, and less frequently with yolk sac tumor, seminoma and dysgerminoma. Our experimental data suggest that beta-hCG production by syncytiotrophoblastic giant cells in association with embryonal carcinoma is a result of trophoblastic differentiation of embryonal carcinoma. Moreover, it was proved that the production of beta-hCG by human embryonal carcinomas is regulated by more factors than is the case for human choriocarcinomas.

A transplantable tumor strain designated YNnu and a cultured cell line designated YN were established from the human paratesticular rhabdomyosarcoma of a 15-year-old boy. In vitro the cells showed ultrastructural features of immature mesenchymal cells, and a few cells were labeled by antibodies to myoglobin and/or desmin. In nude mice, the cells became to contain numerous myofibrils with Z-bands, and considerable number of cells reacted with anti-myoglobin and/or anti-desmin antibodies. We conclude that spindle-shaped or small round cells are the most immature rhabdomyoblast with multiplicity for cellular differentiation.

The production of alpha-fetoprotein (AFP) by human germ cell tumors was studied in surgical specimens, cultured cells and transplanted tumors in nude mice. AFP was detected most frequently in yolk sac (endodermal sinus) tumors, and it was also detected, though only occasionally, in embryonal carcinomas and in teratomas. AFP-positive cells in teratomas presented a glandular or hepatoid appearance. Our experimental data suggest that AFP production in embryonal carcinomas is due to the functional expression of yolk sac differentiation preceding its morphologic expression. Although the transplanted tumors maintained the productivity of AFP, the cultured cells were not successful in maintaining a continuous AFP production.