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We compared the safety and efficacy in mice with peritoneal carcinomatosis of two etoposide formulations: an aqueous solution (Etp-sol) and particles suspended in oil (the addition products of iodine and the ethyl esters of the fatty acids obtained from poppy-seed oil (Lipiodol) or sesame oil; Etp-oil). We also investigated tissue distribution of etoposide in rats treated with Etp-oil and Etp-sol. Etoposide was injected intraperitoneally at concentrations ranging from 52 to 392 mg/kg (increasing geometrically by a factor of 1.4). The 50% lethal dose (LD50), determined over a 2-week period of observation, was 135 mg/kg for Etp-oil and 108 mg/kg for Etp-sol. Autopsy findings included macroscopic intestinal bleeding, necrosis of the intestinal mucosa, and pulmonary congestion in mice from both treatment groups. In the efficacy trials. 10(6) P388 leukemia cells were transplanted into CDF1 male mice, and Etp-oil and Etp-sol were injected at doses of 20 mg/kg and 80 mg/kg. In the groups receiving the 20 mg/kg dose, 11 of 19 mice in the Etp-oil group survived to day 60 compared with 3 of 20 mice in the Etp-sol group. Toxicity-related deaths occurred in 1 of 20 mice treated with 80 mg/kg Etp-oil and in 8 of 20 mice treated with 80 mg/kg Etp-sol. No cancer-related deaths were associated with the 80 mg/kg dose in either treatment group. Our findings showed that the Etp-oil was associated with a lower toxicity and a higher efficacy than the Etp-sol. To evaluate tissue distribution, rats were injected intraperitoneally with 5 mg/kg body weight of Etp-sol or Etp-oil. The tissue distribution of etoposide was subsequently analyzed by high performance liquid chromatography. Compared with Etp-sol, Etp-oil delivered significantly greater amounts of etoposide and for a longer period to the omentum, taken as representative of the intraperitoneal tissue, and the etoposide concentration in blood plasma was increased more slowly and decreased more gradually. [ABSTRACT FROM AUTHOR]

Conditioned taste aversion (CTA) is an essential ability for animals to consume food safely and is regulated by neuromodulatory systems including the dopamine, noradrenaline, serotonin, and acetylcholine systems. However, because few studies focused on a comprehensive understanding of whole-brain activities, how these neuromodulators contribute to the process of CTA remains an open issue. 18 F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) can visualize activated regions within the whole brain simultaneously and noninvasively. This study aimed to understand the mechanisms of CTA, especially focusing on the retrieval process after CTA acquisition by FDG-PET imaging. CTA was established in rats who received an intraoral application of saccharin solution (IOAS) on the first day (Day 1), a LiCl i.p. injection after an IOAS on Day 2, and an IOAS on Day 3 (CTA group). The subtraction images of Day 3 of the SHAM group, which received a 0.9 % NaCl (saline) injection instead of a LiCl on Day 2, from those of Day 3 of the CTA group revealed increases in FDG signals in multiple brain regions including the substantia nigra, ventral tegmental area, locus coeruleus, dorsal raphe, and nucleus basalis magnocellularis, in addition to the hippocampus and nociception-related regions, including the parabrachial nucleus and solitary nucleus. On the other hand, the visceral pain induced by the LiCl injection increased FDG signals in the primary and secondary somatosensory and insular cortices in addition to the parabrachial nucleus and solitary nucleus. These results suggest that the retrieval process of CTA induces brain regions producing neuromodulators and pain-related brainstem., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

N,N-diethyl-meta-toluamide (DEET) is a widely used insect repellent, with minimal skin permeation and sustained repellent activity in the superficial layers of the skin. In this study, we prepared a 10% DEET formulation consisting of 40% ethanol with or without 2% poly(oxyethylene)/poly(oxypropylene) butyl ether (POE-POP), an amphiphilic random copolymer. Further, we demonstrated the effects of POE-POP on tensile stress (stickiness), hydrophobicity, skin retention, permeation, and repellent activity of DEET. Stickiness was measured in male ICR mice (7-week old), and skin retention and permeation were evaluated in male Wistar rats (7-week old). In addition, female Aedes albopictus were used to measure the repellent action of DEET. The addition of POE-POP did not affect stickiness, volatility, and degradability but decreased logP and increased viscosity of DEET. Next, we demonstrated the behavior of DEET formulations in the rat skin. POE-POP prolonged the retention of DEET in the superficial layers of the rat skin (skin surface and stratum corneum) and decreased the penetration of DEET into rat skin tissues (epithelium and dermis). The repellent effect of DEET was also enhanced by the addition of POE-POP. However, severe skin damage was not observed after repetitive treatment with DEET formulations containing POE-POP for one month (twice a day). In conclusion, we demonstrated that a 10% DEET formulation consisting of 40% ethanol and 2% POE-POP attenuated the skin penetration and prolonged the repellent action of DEET without causing stickiness and skin damage. We conclude that the combination of ethanol and POE-POP is useful as a safe and effective delivery system for the development of insect repellent formulations containing DEET., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Kawaguchi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Andexanet alfa is a modified recombinant human factor Xa (FXa) that was designed to serve as a binding target for FXa inhibitors as decoy protein. It sequesters FXa inhibitors from binding to endogenous FXa, thereby reversing anticoagulant effect of FXa inhibitors. Andexanet alfa has been approved in March 2022 in Japan for patients with life-threatening or uncontrolled bleeding while on treatment with a FXa inhibitor, apixaban, rivaroxaban, or edoxaban tosilate hydrate. It is administered via two dosing regimens, based on the type of FXa inhibitor, dose, and time since the last dose. In nonclinical studies, andexanet alfa significantly inhibited bleeding induced by FXa inhibitors in animal bleeding models. In the development for Japanese patients, the following two clinical studies have been conducted to confirm the efficacy and safety. First, safety and the reversal effect of andexanet alfa on the FXa inhibitor-mediated anticoagulant activity in healthy adults were confirmed in the overseas phase 2 study including Japanese subjects. Next, the reversal effect of andexanet alfa on the anticoagulation activity and the hemostasis were demonstrated in patients with acute major bleeding while on FXa inhibitor treatment in the global phase 3b/4 study (ANNEXA-4 study). The subgroup analysis of Japanese population showed that the efficacy and safety results were consistent with those of overall population. Andexanet alfa is the first approved reversal agent for FXa inhibitors in Japan and is expected to contribute to the improvement of prognosis in patients with fatal and/or uncontrolled bleeding by timely reversing anticoagulant effect of FXa inhibitors.

N , N -diethyl-3-toluamide (DEET) is one of the most widely used insect repellents in the world. It was reported that a solution containing 6-30% cyclodextrin (CD) as a solvent instead of ethanol (EtOH) provided an enhancement of the repellent action time duration of the DEET formulation, although the high-dose CD caused stickiness. In order to overcome this shortcoming, we attempted to prepare a 10% DEET formulation using EtOH containing low-dose CDs (β-CD, 2-hydroxypropyl-β-CD (HPβCD), methyl-β-CD, and sulfobutylether-β-CD) as solvents (DEET/EtOH/CD formulations). We determined the CD concentration to be 0.1% in the DEET/EtOH/CD formulations, since the stickiness of 0.1% CDs was not felt (approximately 8 × 10 -3 N). The DEET residue on the skin superficial layers was prolonged, and the drug penetration into the skin tissue was decreased by the addition of 0.1% CD. In particular, the retention time and attenuated penetration of DEET on the rat skin treated with the DEET/EtOH/HPβCD formulation was significantly higher in comparison with that of the DEET/EtOH formulation without CD. Moreover, the repellent effect of DEET was more sustained by the addition of 0.1% HPβCD in the study using Aedes albopictus . In conclusion, we found that the DEET/EtOH/HPβCD formulations reduced the skin penetration of DEET and prolonged the repellent action without stickiness.

Objective: Drug therapy is occasionally accompanied by an idiosyncratic severe toxicity, which occurs very rarely, but can lead to patient mortality. Methazolamide, an anti-glaucomatous agent, could cause severe skin eruptions called Stevens-Johnson syndrome/toxic epidermal necrolyis (SJS/TEN). Its precise etiology is still uncertain. In this study, the metabolism of methazolamide was investigated in immortalized human keratinocytes to reveal the possible mechanism which causes SJS/TEN., Methods: The metabolism of methazolamide was studied using immortalized human keratinocytes, HaCaT cells. HPLC was used to isolate a metabolite from the culture medium. Mass spectrometry (LCMS/ MS) was employed for its characterization. Three typical chemical inducers were assessed for the inducibility of cytochrome P450, and methimazole was used as the inhibitor of flavin-containing monooxygenase (FMO)., Results: A sulfonic acid, N-[3-methyl-5-sulfo-1,3,4-thiadiazol-2(3H)-ylidene]acetamide (MSO) was identified as the final metabolite. Dexamethasone and β-naphthoflavone behaved as an inducer of cytochrome P450 in the metabolism, but isoniazid did not. The effect of methimazole was not consistent. We did not detect any glucuronide nor any mercapturic acid (N-acetylcysteine conjugate)., Conclusion: N-[3-methyl-5-sulfo-1,3,4-thiadiazol-2(3H)-ylidene]acetamide (MSO) is not considered to be a direct product of an enzymatic reaction, but rather an auto-oxidation product of N-[3-methyl-5- sulfe-1,3,4-thiadiazol-2(3H)-ylidene]acetamide, a chemically unstable sulfenic acid, which is produced by cytochrome P450 from the β-lyase product of cysteine conjugate of methazolamide. MSO is considered to be susceptible to glutathione and to return to glutathione conjugate of methazolamide, forming a futile cycle. A hypothetical scenario is presented as to the onset of the disease., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Neuronal cell death in neurodegenerative diseases is not fully understood. Here we report that mutant huntingtin (Htt), a causative gene product of Huntington’s diseases (HD) selectively induces a new form of necrotic cell death, in which endoplasmic reticulum (ER) enlarges and cell body asymmetrically balloons and finally ruptures. Pharmacological and genetic analyses revealed that the necrotic cell death is distinct from the RIP1/3 pathway-dependent necroptosis, but mediated by a functional deficiency of TEAD/YAP-dependent transcription. In addition, we revealed that a cell cycle regulator, Plk1, switches the balance between TEAD/YAP-dependent necrosis and p73/YAP-dependent apoptosis by shifting the interaction partner of YAP from TEAD to p73 through YAP phosphorylation at Thr77. In vivo ER imaging with two-photon microscopy detects similar ER enlargement, and viral vector-mediated delivery of YAP as well as chemical inhibitors of the Hippo pathway such as S1P recover the ER instability and necrosis in HD model mice. Intriguingly S1P completely stops the decline of motor function of HD model mice even after the onset of symptom. Collectively, we suggest approaches targeting the signalling pathway of TEAD/YAP-transcription-dependent necrosis (TRIAD) could lead to a therapeutic development against HD.

Mutant ataxin-1 (Atxn1), which causes spinocerebellar ataxia type 1 (SCA1), binds to and impairs the function of high-mobility group box 1 (HMGB1), a crucial nuclear protein that regulates DNA architectural changes essential for DNA damage repair and transcription. In this study, we established that transgenic or virus vector-mediated complementation with HMGB1 ameliorates motor dysfunction and prolongs lifespan in mutant Atxn1 knock-in (Atxn1-KI) mice. We identified mitochondrial DNA damage repair by HMGB1 as a novel molecular basis for this effect, in addition to the mechanisms already associated with HMGB1 function, such as nuclear DNA damage repair and nuclear transcription. The dysfunction and the improvement of mitochondrial DNA damage repair functions are tightly associated with the exacerbation and rescue, respectively, of symptoms, supporting the involvement of mitochondrial DNA quality control by HMGB1 in SCA1 pathology. Moreover, we show that the rescue of Purkinje cell dendrites and dendritic spines by HMGB1 could be downstream effects. Although extracellular HMGB1 triggers inflammation mediated by Toll-like receptor and receptor for advanced glycation end products, upregulation of intracellular HMGB1 does not induce such side effects. Thus, viral delivery of HMGB1 is a candidate approach by which to modify the disease progression of SCA1 even after the onset., (© 2014 The Authors. Published under the terms of the CC BY 4.0 license.)

Among noninvasive functional brain imaging techniques, (18) F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) has a comparative advantage in detecting active brain regions in freely locomoting animals. We developed an [(18) F]FDG-PET protocol that visualizes active brain regions that respond preferentially to citrate-induced multiple behaviors in freely locomoting rats. In addition, c-Fos immunohistochemistry, an activity-dependent mapping, was performed to examine whether the areas detected by PET correspond to regions with c-Fos-immunopositive neurons. Citrate (0.1 M) was intraorally applied to detect activated brain regions responding to gustation and the rejection behaviors including gaping and tongue protrusion, which would potently activate the limbic system. PET images during citrate stimulation were subtracted from those obtained during free locomotion or during application of distilled water. Citrate increased FDG signals in multiple gustation-related regions: the nucleus accumbens (core and shell), the ventromedial nucleus of the thalamus, the basolateral and central nuclei of the amygdala, the hypothalamus, and the insular cortex. In addition, the ventrolateral striatum and the cingulate and entorhinal cortices, which have received less attention in the field of gustatory studies, also showed an increase in FDG signals. As expected, c-Fos-immunopositive cells were also found in these regions, suggesting that increased FDG signals induced by intraoral citrate injection are likely to reflect neural activity in these regions. Our [(18) F]FDG-PET protocol reveals the contributions of multiple brain regions responding to aversive taste in freely locomoting rats, and this approach may aid in the identification of unknown neural networks especially relating to the limbic information processing., (Copyright © 2013 Wiley Periodicals, Inc.)

It is hypothesized that a common underlying mechanism links multiple neurodegenerative disorders. Here we show that transitional endoplasmic reticulum ATPase (TERA)/valosin-containing protein (VCP)/p97 directly binds to multiple polyglutamine disease proteins (huntingtin, ataxin-1, ataxin-7 and androgen receptor) via polyglutamine sequence. Although normal and mutant polyglutamine proteins interact with TERA/VCP/p97, only mutant proteins affect dynamism of TERA/VCP/p97. Among multiple functions of TERA/VCP/p97, we reveal that functional defect of TERA/VCP/p97 in DNA double-stranded break repair is critical for the pathology of neurons in which TERA/VCP/p97 is located dominantly in the nucleus in vivo. Mutant polyglutamine proteins impair accumulation of TERA/VCP/p97 and interaction of related double-stranded break repair proteins, finally causing the increase of unrepaired double-stranded break. Consistently, the recovery of lifespan in polyglutamine disease fly models by TERA/VCP/p97 corresponds well to the improvement of double-stranded break in neurons. Taken together, our results provide a novel common pathomechanism in multiple polyglutamine diseases that is mediated by DNA repair function of TERA/VCP/p97.

The spinocerebellar ataxia type 7 (SCA7) gene product, Ataxin-7 (ATXN7), localizes to the nucleus and has been shown to function as a component of the TATA-binding protein-free TAF-containing-SPT3-TAF9-GCN5-acetyltransferase transcription complex, although cytoplasmic localization of ATXN7 in affected neurons of human SCA7 patients has also been detected. Here, we define a physiological function for cytoplasmic ATXN7. Live imaging reveals that the intracellular distribution of ATXN7 dynamically changes and that ATXN7 distribution frequently shifts from the nucleus to the cytoplasm. Immunocytochemistry and immunoprecipitation demonstrate that cytoplasmic ATXN7 associates with microtubules (MTs), and expression of ATXN7 stabilizes MTs against nocodazole treatment, while ATXN7 knockdown enhances MT degradation. Interestingly, normal and mutant ATXN7 similarly associate with and equally stabilize MTs. Taken together, these findings provide a novel physiological function of ATXN7 in the regulation of cytoskeletal dynamics, and suggest that abnormal cytoskeletal regulation may contribute to SCA7 disease pathology.

Background: When students proceed to junior high school from elementary school, rapid changes in the environment occur, which may cause various behavioral and emotional problems. However, the changes in cognitive functions during this transitional period have rarely been studied., Methods: In 158 elementary school students from 4th- to 6th-grades and 159 junior high school students from 7th- to 9th-grades, we assessed various cognitive functions, including motor processing, spatial construction ability, semantic fluency, immediate memory, delayed memory, spatial and non-spatial working memory, and selective, alternative, and divided attention., Results: Our findings showed that performance on spatial and non-spatial working memory, alternative attention, divided attention, and semantic fluency tasks improved from elementary to junior high school. In particular, performance on alternative and divided attention tasks improved during the transitional period from elementary to junior high school., Conclusion: Our finding suggests that development of alternative and divided attention is of crucial importance in the transitional period from elementary to junior high school., (Copyright © 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)

The in vivo metabolism of methazolamide, a carbonic anhydrase inhibitor, was studied using guinea pigs as the animals. (14)C-Labeled methazolamide was synthesized. Eighty percent of intraperitoneally injected radioactivity was recovered from urine and feces within 24 hours. HPLC analysis on a C(18) column detected 2 radioactive metabolites (Peaks A and B). The Peaks A and B were isolated from the urine of the animals dosed with non-radioactive methazolamide.They were purified on the C(18) column. Their chemical structure was revealed by UV-absorbance spect a and LC/MS, and confirmed by comparing it with that of chemically synthesized compound. They were a glucuronide, (2-acetylimino-3-methyl-Δ(4)-1,3,4-thiadiazol-5-yl)-1-thio-β-D-glucopyranosiduronic acid, and a sulfonic acid, N-[3-methyl-5-sulfo-1,3,4-thiadiazol-2(3H)-ylidene]acetamide.

Dopamine receptor D(2) (DRD2) has two splicing isoforms, a long form (D2L) and short form (D2S), which have distinct functions in the dopaminergic system. However, the regulatory mechanism of the alternative splicing of DRD2 is unknown. In this study, we examined which splicing factors regulate the expression of D2L and D2S by over-expressing several RNA-binding proteins in HEK293 cells. In a cellular splicing assay, the over-expression of polypyrimidine tract-binding protein 1 (PTBP1) reduced the expression of D2S, whereas the knockdown of PTBP1 increased the expression of D2S. We also identified the regions of DRD2 that are responsive to PTBP1 using heterologous minigenes and deletion mutants. Our results indicate that PTBP1 regulates the alternative splicing of DRD2. Considering that DRD2 inhibits cAMP-dependent protein kinase A, which modulates the intracellular localization of PTBP1, PTBP1 may contribute to the autoregulation of DRD2 by regulating the expression of its isoforms.

Our experience and prejudice concerning food play an important role in modulating gustatory information processing; gustatory memory stored in the central nervous system influences gustatory information arising from the peripheral nervous system. We have elucidated the mechanism of the "top-down" modulation of taste perception in humans using functional magnetic resonance imaging (fMRI) and demonstrated that gustatory imagery is mediated by the prefrontal (PFC) and insular cortices (IC). However, the temporal order of activation of these brain regions during gustatory imagery is still an open issue. To explore the source of "top-down" signals during gustatory imagery tasks, we analyzed the temporal activation patterns of activated regions in the cerebral cortex using another non-invasive brain imaging technique, magnetoencephalography (MEG). Gustatory imagery tasks were presented by words (Letter G-V) or pictures (Picture G-V) of foods/beverages, and participants were requested to recall their taste. In the Letter G-V session, 7/9 (77.8%) participants showed activation in the IC with a latency of 401.7±34.7 ms (n = 7) from the onset of word exhibition. In 5/7 (71.4%) participants who exhibited IC activation, the PFC was activated prior to the IC at a latency of 315.2±56.5 ms (n = 5), which was significantly shorter than the latency to the IC activation. In the Picture G-V session, the IC was activated in 6/9 (66.7%) participants, and only 1/9 (11.1%) participants showed activation in the PFC. There was no significant dominance between the right and left IC or PFC during gustatory imagery. These results support those from our previous fMRI study in that the Letter G-V session rather than the Picture G-V session effectively activates the PFC and IC and strengthen the hypothesis that the PFC mediates "top-down" control of retrieving gustatory information from the storage of long-term memories and in turn activates the IC.

Gene expression studies have shown that expression patterns of several genes have changed during the development of alcoholism. Gene expression is regulated not only at the level of transcription but also through alternative splicing of pre-mRNA. In this review, we discuss some of the evidence suggesting that alternative splicing of candidate genes such as DRD2 (encoding dopamine D2 receptor) may form the basis of the mechanisms underlying the pathophysiology of alcoholism. These reports suggest that aberrant expression of splice variants affects alcohol sensitivities, and alcohol consumption also regulates alternative splicing. Thus, investigations of alternative splicing are essential for understanding the molecular events underlying the development of alcoholism.

Aims: Fatigue is a common symptom in modern society. In order to clarify the mechanisms underlying fatigue, we examined the association between central nervous system fatigue and autonomic nerve activity., Main Methods: The study group consisted of 20 healthy subjects. They performed the 2-back test for 30 min to induce fatigue. Just before and after the fatigue-inducing session, they completed the advanced trail making test (ATMT) for 30 min as a fatigue-evaluating task session. In order to measure autonomic nerve activity, electrocardiograms were monitored continuously throughout the experiment., Key Findings: After the fatigue-inducing task session, impaired task performance was demonstrated based on the total trial number and error counts of the ATMT. During the task session, although task performance as measured using the accuracy and the mean reaction time of the 2-back test was almost unchanged, electrocardiographic R-R wave interval analyses showed a decreased high-frequency component power and an increasing trend in the low-frequency component power/high-frequency component power ratio., Significance: Decreased vagal nerve activity and increased sympathetic nerve activity are associated with central nervous system fatigue.

Properties of repetitive firing, including spike adaptation, are considered to play an essential role in controlling neural excitability in the central nervous system. Noradrenaline is one of major neurotranmitters that modulate repetitive firing in the cerebral cortex. Although activation of beta-adrenoceptors increases firing frequency similarly to noradrenaline, it is still controversial whether alpha(1)-adrenoceptor activation influences repetitive firing. In the present study, we examined the effects of adrenoceptor agonists on firing properties and the intracellular mechanism for alpha(1)-adrenoceptor-dependent modulation of firing in pyramidal neurons of rat cerebral cortex. In agreement with previous reports, bath application of 100microM isoproterenol, a beta-adrenoceptor agonist, increased firing frequency in response to a long intracellular depolarizing current injection. Phenylephrine (100microM), an alpha(1)-adrenoceptor agonist, also increased firing rate, which was inhibited by 100microM prazosin, an alpha1-adrenoceptor antagonist. The extent of increment in firing rate is comparable to that induced by isoproterenol. Furthermore, phenylephrine's effects on firing properties were mimicked by 2-5microM phorbol ester, a protein kinase C (PKC) activator, and pre-application of 10microM chelerythrine, a PKC inhibitor, prevented phenylephrine-induced facilitation of repetitive firing. These results suggest that phenylephrine has a facilitatory effect on repetitive firing through PKC activation.

The dopamine system plays a well-established role in alcoholism. In this study, we examined the association between the single-nucleotide polymorphism (SNP) rs1076560 of the dopamine receptor D2 (DRD2) gene and susceptibility to alcoholism. SNP rs1076560 (C/A) is located in intron 6 of DRD2, where it is 1.4 kb downstream from alternative exon 6 and 83 bp upstream from exon 7. A total of 248 alcoholic patients and 322 healthy controls, all Japanese males, were genotyped for rs1076560 polymorphism by direct sequencing and allele-specific PCR. Data were analyzed using standard chi(2) statistics and a backwards logistic regression approach to adjust for the contribution of aldehyde dehydrogenase-2 (ALDH2) genotype status. The DRD2 risk allele A was more prevalent in the alcoholic patients (40.1%) than in the healthy controls (34.0%) (P=0.034, odds ratio=1.300, 95% confidence interval=1.020-1.657). These data identify SNP rs1076560 as a potentially important variable in the development of alcoholism.

Background: Although the neural mechanism of chronic fatigue syndrome has been investigated by a number of researchers, it remains poorly understood., Methods: Using functional magnetic resonance imaging, we studied brain responsiveness in 6 male chronic fatigue syndrome patients and in 7 age-matched male healthy volunteers. Responsiveness of auditory cortices to transient, short-lived, noise reduction was measured while subjects performed a fatigue-inducing continual visual search task., Results: Responsiveness of the task-dependent brain regions was decreased after the fatigue-inducing task in the normal and chronic fatigue syndrome subjects and the decrement of the responsiveness was equivalent between the 2 groups. In contrast, during the fatigue-inducing period, although responsiveness of auditory cortices remained constant in the normal subjects, it was attenuated in the chronic fatigue syndrome patients. In addition, the rate of this attenuation was positively correlated with the subjective sensation of fatigue as measured using a fatigue visual analogue scale, immediately before the magnetic resonance imaging session., Conclusion: Chronic fatigue syndrome may be characterised by attenuation of the responsiveness to stimuli not directly related to the fatigue-inducing task.

By recalling gustatory memories, it is possible to generate vivid gustatory perceptions in the absence of gustatory inputs. This gustatory image influences our gustatory processing. However, the mechanism of the "top-down" modulation of gustatory perception in the human is still unclear. Our findings propose a new perspective on the neural basis of gustatory processing. Although gustatory imagery and gustatory perception shared common parts of neural substrates, there was an asymmetrical topography of activation in the insula: the left insula was predominantly activated by gustatory imagery tasks. In addition, the middle and superior frontal gyri were not activated by gustatory perception but they participated in the generation of gustatory hallucinations. These regions in the frontal cortex may mediate the "top-down" control of retrieving gustatory information from the storage of long-term memories.

To assess whether retinoblastoma formation is associated with the expression of high mobility group (HMG) A2 protein, a transcription factor that is highly expressed during embryogenesis and completely repressed in normal adult tissues, we performed Northern and Western blots and RT-PCR analyses, and immunohistochemistry to test for HMGA2 expression. We used established retinoblastoma cell lines in tumors grown in nude mice and clinical retinoblastoma specimens, and contrasted these tumors with normal embryonic and adult retina. Adenoviral-mediated antisense experiments were conducted on the retinoblastoma cell lines to suppress HMGA2 expression and determine if cell proliferation is HMGA2-dependent. We also transfected a retinoblastoma cell line to identify cis-regulatory elements and transcription initiation sites on the HMGA2 gene promoter. HMGA2 gene expression was silenced in terminally differentiated retina of 6-wk-old mice, but it was detected in retina of a 13.5-d postcoitum embryo. Reactivation of HMGA2 gene expression was observed in the retinoblastoma cell lines Y79, WERI-Rb1, and TOTL-1, in tumors derived from some of these cells propagated in nude mice, and in a high frequency of retinoblastomas excised from human patients. This suggests that expression of HMGA2 gene in retinoblastoma cells involves a derepression process. By using an antisense approach to block HMGA2 expression, we observed a decrease in the number of proliferating retinoblastoma cells. As a 1st step toward understanding HMGA2 gene reactivation in retinoblastoma, we mapped the 2 transcription initiation sites and associated positive regulatory elements within the WERI-Rb1 cells. Our discovery of derepression of HMGA2 gene expression in retinoblastoma provides the 1st evidence that this protein might contribute to neoplastic transformation of retina cells.

Functional imaging technique using positron emission tomography (PET) has made it possible to localize functional brain regions in the human brain by detecting changes in regional cerebral blood flow (rCBF). Performing PET studies in the monkey will aid in integrating monkey electrophysiological research with human PET studies. We examined changes in rCBF during olfactory or combined olfactory and gustatory (flavour) stimulation using PET in the alert rhesus monkey. Olfactory or flavour stimulation with acetic acid or apple increased rCBF in the prepyriform area, substantia innominata and amygdala. Besides these areas, flavour stimulation increased rCBF in the anterior insula and frontal operculum, orbitofrontal cortex, inferior frontal gyrus and cerebellum. Apple odour or flavour stimuli increased rCBF in the inferior occipital gyrus in addition to the above areas. These findings suggest that the increases of rCBF in response to neural activities in the primary olfactory and gustatory cortices are detectable by the use of PET. In addition, regions activated by apple stimuli suggest that higher brain function might be detected with PET in the alert monkey.

Bovine kidney and liver homogenates degraded a cysteine conjugate of methazolamide, S-(5-acetylimino-4-methyl-Delta2-1,3,4-thiadiazolin-2-yl)cysteine. We isolated the degradation product following incubation with kidney homogenate by high-performance liquid chromatography on reversed-phase columns. The chemical structure was confirmed by proton and carbon-13 nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR, respectively), and elemental analysis by high-resolution mass spectrometry to be N-(3-methyl-5-mercapto-Delta4-1,3,4-thiadiazol-2-yl)acetamide, a thiol compound. The reaction is thought to be catalyzed by a pyridoxal-dependent enzyme(s) as indicated by an inhibition study using aminooxyacetic acid. Possible involvement of the thiol compound in the development of an adverse effect is discussed.

The serum-IgE (sIgE) levels of eight patients with cataract complicated by atopic dermatitis (atopic cataract) who had undergone cataract surgery were reported. Five of them were diagnosed as having cataract the first visit to our eye clinic. The other three cases did not show cataract at the first visit but developed it later. The average sIgE of the five cases with cataract was 25,478 +/- 15,936 (mean +/- standard deviation) iu/ml whereas that of the latter three cases without cataract, at the first visit was 4,638 +/- 1,810 iu/ml. The average sIgE of these three cases when their cataracts were diagnosed first went up to 13,210 +/- 5,574 iu/ml. These results suggested that a high level of sIgE may be a warning of the appearance of atopic cataract.

Trabeculectomy often fails because of scarring of the filtering bleb, which is caused by the proliferation of fibroblasts. In this study, we investigated the inhibitory effect of Arg-Gly-Asp-Ser (RGDS) oligopeptide, a cell binding domain of fibronection molecules, on the attachment of fibroblasts in vitro and on scarring of filtering bleb after trabeculectomy on rabbits' eyes. The following results were obtained. 1. RGDS inhibited the attachment of rabbit conjunctival fibroblasts significantly (p < 0.01) when it was added to the culture medium at final concentrations of 2 and 5 mg/ml. 2. The administration of 0.2 ml of RGDS solution (5 mg/ml) into the filtering bleb 3 days after surgery caused significant reductions of intra ocular pressure compared with the control maintained the bleb more than 13 days whereas the blebs of the control eyes disappeared within 6 days (p < 0.01). 3. No complications were caused on the eyeballs of the rabbits by the administration of RGDS.

Among the Arg-Gly-Asp (RGD)-containing sequences that are known to be cell-binding domains of fibronectin, 500 migrograms/ml of Arg-Gly-Asp-Ser (RGDS) and Gly-Arg-Gly-Asp-Ser showed 100% inhibition of the attachment of cultured lens epithelial cells (TOTL-86 cells), when they were added to culture medium and coincubated with the cells for 24 h whereas RGD at concentrations of 500, 1,000 and 2,000 micrograms/ml had no such activity. After 48 h of cocultivation of 800, 400 or 200 micrograms/ml of RGDS with TOTL-86 cells, the percentage of floating cells was 100, 30.1 or 11.1%, respectively. After 144 h of cocultivation with RGDS, the percentage of floating cells was 1.6, 2.4 or 1.9%, respectively, indicating that RGDS was not cytotoxic to lens epithelial cells. However, replacing the medium with fresh medium containing new RGDS peptide resulted in floating of cells. We also studied the inhibitory effect of two other amino acid sequences that are found in cell-binding sites of the fibronectin molecule: Glu-Ile-Leu-Asp-Val-Pro-Ser-Thr (EILDVPST) and Arg-Glu-Asp-Val (REDV). At 500 and 1,000 micrograms/ml, respectively, neither EILDVPST nor REDV has an inhibitory effect on the attachment of TOTL-86 cells, while RGDS at a concentration of 500 micrograms/ml completely inhibited the attachment of the cells in 24 h of incubation.