Deep learning-based sleep stage classification with cardiorespiratory and body movement activities in individuals with suspected sleep disorders

Deep learning methods have gained significant attention in sleep science. This study aimed to assess the performance of a deep learning-based sleep stage classification model constructed using fewer physiological parameters derived from cardiorespiratory and body movement data. Overnight polysomnography (PSG) data from 123 participants (age: 19-82 years) with suspected sleep disorders were analyzed. Multivariate time series data, including heart rate, respiratory rate, cardiorespiratory coupling, and body movement frequency, were input into a bidirectional long short-term memory (biLSTM) network model to train and predict five-class sleep stages. The trained model's performance was evaluated using balanced accuracy, Cohen's κ coefficient, and F1 scores on an epoch-per-epoch basis and compared with the ground truth using the leave-one-out cross-validation scheme. The model achieved an accuracy of 71.2 ± 5.8%, Cohen's κ of 0.425 ± 0.115, and an F1 score of 0.650 ± 0.083 across all sleep stages, and all metrics were negatively correlated with the apnea-hypopnea index, as well as age, but positively correlated with sleep efficiency. Moreover, the model performance varied for each sleep stage, with the highest F1 score observed for N2 and the lowest for N3. Regression and Bland-Altman analyses between sleep parameters of interest derived from deep learning and PSG showed substantial correlations (r = 0.33-0.60) with low bias. The findings demonstrate the efficacy of the biLSTM deep learning model in accurately classifying sleep stages and in estimating sleep parameters for sleep structure analysis using a reduced set of physiological parameters. The current model without using EEG information may expand the application of unobtrusive in-home monitoring to clinically assess the prevalence of sleep disorders outside of a sleep laboratory.

A monoacylglyceryltrimethylhomoserine, 21F121-A, containing a branched acyl group from Penicillium glaucoroseum

A new monoacylglyceryltrimethylhomoserine, 21F121-A (1), was isolated from the culture of Penicillium glaucoroseum (21F00121) by LCMS-guided purification. The structure was elucidated by NMR and mass spectrometries. The absolute configuration of the homoserine moiety was analyzed by the ECD spectrum after acid hydrolysis, and the S-configuration of the glycerol moiety was determined based on the spectrum of the 1,2-dibenzoyl derivative after acid hydrolysis. Although a variety of diacylglyceryltrimethylhomoserine is distributed in lower plants and fungi, a limited number of studies on monoacyl derivatives have been reported. This is the fourth sample of monoacylglyceryltrimethylhomoserine discovered from a natural source, and the second sample isolated from a fungus. Compound 1 contains an unusual branched pentaene chain attached at the sn-1 position of glycerol and weakly inhibited the growth of HCT116 cells.

Colletofragarone A2 Inhibits Cancer Cell Growth In Vivo and Leads to the Degradation and Aggregation of Mutant p53

Mutant p53 not only loses its original tumor suppressor function but also acquires new abilities regarding oncogenic progression. Therefore, the strategy of targeting mutant p53 has attracted attention for cancer therapy. We isolated colletofragarone A2 (CF) from the fungus Colletotrichum sp. (13S020), which decreases mutant p53 levels in cells, and herein examine its effect on mutant p53. CF showed more potent cytotoxic activities on cells with p53R175H structural mutants than those with different p53 statuses such as a DNA-contact mutant, wild-type, and null cells. CF markedly decreased tumor cell growth in vivo using a mouse xenograft model with HuCCT1 (p53R175H) cells. Cotreatment of SK-BR-3 (p53R175H) cells with CF and cycloheximide decreased mutant p53 levels by promoting p53 degradation. In the presence of MG-132, CF induced the accumulation of the aggregated mutant p53. These results suggest that CF inhibits the function of molecular chaperones such as HSP90.

Formation of glyco-functionalized interfaces for protein binding using polyphenolic glycoside

In this study, a polyphenolic glycoside (α-glucosyl rutin) was used to form glyco-functionalized interfaces for protein binding. α-Glucosyl rutin was coated onto precious metals, metal oxides, and synthetic polymers, including polyethylene and polytetrafluoroethylene with poor surface modifiability. The glyco-functionalized interfaces bound strongly and specifically to concanavalin A and Bauhinia purpurea lectin, which have different carbohydrate specificities. Competitive adsorption tests demonstrated that the binding sites for the abovementioned lectins were glucosyl and rhamnosyl residues, respectively. The glyco-functionalized interfaces maintained the protein binding ability after being stored in aqueous solution for 1 day and in air for 160 days. Once the glyco-functionalized interfaces were formed on gold, silicon dioxide, polystyrene, and polytetrafluoroethylene using α-glucosyl rutin, all the glyco-functionalized interfaces bound to concanavalin A rather than peanut agglutinin.

High rate capability by sulfur-doping into LiFePO4 matrix

Enhanced electrochemical performance of LiFePO₄ for Li-ion batteries has been anticipated by anion doping at the O-site rather than cation doping at the Fe-site. We report on the electrochemical performance of S-doped LiFePO₄ nanoparticles synthesized by a solvothermal method using thioacetamide as a sulfur source. S-doping into the LiFePO₄ matrix expands the lattice due to the larger ionic radius of S²⁻ than that of O²⁻. The lattice parameters a and b increase by around 0.2% with sulfur content, while that of c remains almost unchanged with only 0.03% increase. The S-doping also contributes to the suppression of antisite defects (Fe occupying Li sites), which facilitates the easy migration of Li in the diffusion channels without blockage. Owing to these effects of S-doping, the S-doped LiFePO₄ nanoparticles show enhanced electrochemical properties with a high discharge capacity of ∼113 mA h g⁻¹ even at a high rate of 10C.

S-doped LiFePO₄ nanoparticles with improved electrochemical properties have been synthesized by a single step solvothermal method.

Computational modeling of 137Cs contaminant transfer associated with sediment transport in Abukuma River

A numerical model capable of simulating the transfer of (137)Cs in rivers associated with transport of fine sediment is presented. The accident at Fukushima Dai-ichi Nuclear Power Plant (FDNPP) released radionuclides into the atmosphere, and after fallout several radionuclides in them, such as radiocesium ((134)Cs, (137)Cs) and radioiodine ((131)I) were adsorbed on surface soil particles around FDNPP and transported by surface water. To understand the transport and deposition of the radioactive contaminant along with surface soil particles and its flux to the ocean, we modeled the transport of the (137)Cs contaminant by computing the water flow and the associated washload and suspended load transport. We have developed a two-dimensional model to simulate the plane flow structure, sediment transport and associated (137)Cs contaminant transport in rivers by combining a shallow water flow model and an advection-diffusion equation for the transport of sediment. The proposed model has been applied to the lower reach of Abukuma River, which is the main river in the highly contaminated area around FDNPP. The numerical results indicate that most (137)Cs supplied from the upstream river reach with washload would directly reach to Pacific Ocean. In contrast, washload-oriented (137)Cs supplied from the upstream river basin has a limited role in the radioactive contamination in the river. The results also suggest that the proposed framework of computational model can be a potential tool for understanding the sediment-oriented (137)Cs behavior in rivers.

The pilot study of a Neuropsychological Educational Approach to Cognitive Remediation for patients with schizophrenia in Japan

The main aim of this study is to demonstrate the feasibility and efficacy of a Neuropsychological Educational Approach to Cognitive Remediation (NEAR) in Japan. This multi-site study used a quasi-experimental design. Fifty-one patients with schizophrenia or schizoaffective disorder participated. The NEAR program consisted of two 1-h computer sessions per week and an additional group meeting session lasting 30 to 60 min once a week. The subjects completed 6 months of NEAR sessions before being assessed. Moreover, taking into consideration the possible practice effect, we assessed 21 control patients twice with an interval of 6 months. We assessed cognitive function by using the Japanese version of the Brief Assessment of Cognition in Schizophrenia (BACS-J). Consequently, the NEAR group showed significant improvement in overall cognitive function, and in comparison with the control group, these findings were generally similar except for motor speed. Although the present study has its limitations, it demonstrates that the NEAR is feasible in Japan as well as it is in Western countries.

A balanced diet is necessary for proper entrainment signals of the mouse liver clock

Background

The peripheral circadian clock in mice is entrained not only by light-dark cycles but also by daily restricted feeding schedules. Behavioral and cell culture experiments suggest an increase in glucose level as a factor in such feeding-induced entrainment. For application of feeding-induced entrainment in humans, nutrient content and dietary variations should be considered.

Principal Finding

To elucidate the food composition necessary for dietary entrainment, we examined whether complete or partial substitution of dietary nutrients affected phase shifts in liver clocks of mice. Compared with fasting mice or ad libitum fed mice, the liver bioluminescence rhythm advanced by 3–4 h on the middle day in Per2::luciferase knock-in mice that were administered a standard mouse diet, i.e. AIN-93M formula [0.6–0.85 g/10 g mouse BW] (composition: 14% casein, 47% cornstarch, 15% gelatinized cornstarch, 10% sugar, 4% soybean oil, and 10% other [fiber, vitamins, minerals, etc.]), for 2 days. When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein. A combination of glucose and casein without oil, vitamin, or fiber caused a significant phase advance. When cornstarch in AIN-93M was substituted with glucose, sucrose, fructose, polydextrose, high-amylose cornstarch, or gelatinized cornstarch, the amplitude of phase advance paralleled the increase in blood glucose concentration.

Conclusions

Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment. These findings may assist in the development of dietary recommendations for on-board meals served to air travelers and shift workers to reduce jet lag-like symptoms.

Age-related insulin resistance in hypothalamus and peripheral tissues of orexin knockout mice

AIMS/HYPOTHESIS

Orexin/hypocretin is a hypothalamic neuropeptide that regulates motivated behaviours, such as feeding and arousal, and, importantly, is also involved in energy homeostasis. The aim of this study was to reveal the role of orexin in the regulation of insulin sensitivity for glucose metabolism.

METHODS

Orexin knockout mice fasted overnight underwent oral glucose tolerance testing and insulin tolerance testing. The impact of orexin deficiency on insulin signalling was studied by Western blotting to measure levels of Akt phosphorylation and its upstream and downstream molecules in the hypothalamus, muscle and liver in orexin knockout mice.

RESULTS

We found that orexin deficiency caused the age-related development of impaired glucose tolerance and insulin resistance in both male mice without obesity and female mice with mild obesity, fed a normal chow diet. When maintained on a high-fat diet, these abnormalities became more pronounced exclusively in female orexin knockout mice that developed severe obesity. Insulin signalling through Akt was disrupted in peripheral tissues of middle-aged (9-month-old) but not young adult (2-to-3-month-old) orexin knockout mice fed a normal chow diet. Moreover, basal levels of hypothalamic Akt phosphorylation were abnormally elevated in orexin knockout mice at every age studied, and insulin stimulation failed to increase the level of phosphorylation. Similar abnormalities were observed with respect to GSK3beta phosphorylation in the hypothalamus and peripheral tissues of middle-aged orexin knockout mice.

CONCLUSIONS/INTERPRETATION

Our results demonstrate a novel role for orexin in hypothalamic insulin signalling, which is likely to be responsible for preventing the development of peripheral insulin resistance with age.

Dynamic gene expression of Lin-28 during embryonic development in mouse and chicken

The Caenorhabditis elegans heterochronic gene lin-28 regulates developmental timing in the nematode trunk. We report the dynamic expression patterns of Lin-28 homologues in mouse and chick embryos. Whole mount in situ hybridization revealed specific and intriguing expression patterns of Lin-28 in the developing mouse and chick limb bud. Mouse Lin-28 expression was detected in both the forelimb and hindlimb at E9.5, but disappeared from the forelimb at E10.5, and finally from the forelimb and hindlimb at E11.5. Chicken Lin-28, which was first detected in the limb primordium at stage 15/16, was also downregulated as the stage proceeded. The amino acid sequences of mouse and chicken Lin-28 genes are highly conserved and the similar expression patterns of Lin-28 during limb development in mouse and chicken suggest that this heterochronic gene is also conserved during vertebrate limb development.

ζ-Sarcoglycan is a functional homologue of γ-sarcoglycan in the formation of the sarcoglycan complex

The sarcoglycans (SGs), transmembrane components of the dystrophin-associated glycoprotein complex, are stable and functional only when they assemble into a tetrameric complex in muscle cells. A defect in any one of the four SG members disrupts the entire SG complex (SGC) and causes limb-girdle muscular dystrophy. zeta-SG has been recently found as a transmembrane protein homologous to gamma-SG and delta-SG. To characterize zeta-SG in complex formation, we co-transfected expression vectors encoding all six SGs (alpha-, beta-, gamma-, delta-, epsilon- and zeta-SG) and dystroglycan into Chinese hamster ovary cells. Immunoprecipitation analysis showed that zeta-SG or gamma-SG formed a SGC with beta-SG and delta-SG plus alpha-SG or epsilon-SG, revealing that zeta-SG can form two types of SGCs (alpha-beta-zeta-delta or epsilon-beta-zeta-delta). This result indicates the functional resemblance of zeta-SG to gamma-SG rather than delta-SG, although phylogenetic analysis suggests that zeta-SG is evolutionally closer to delta-SG than to gamma-SG. Reverse transcription (RT)-PCR showed that the expression pattern of the transcript was almost the reciprocal of that of gamma-SG in various mouse tissues and that the zeta-SG transcript was especially abundant in the brain, suggesting that zeta-SG might play a particular role in the central nervous system.

Mechanical stress induces expression of cytokines in human periodontal ligament cells

OBJECTIVE

Periodontal tissue has a unique structure in that the human periodontal ligament (hPDL) lies between the hard tissues of cementum and alveolar bone. Although the role of cytokines in hPDL function is not clearly understood, we investigated the effect of mechanical stress as hydrostatic pressure (HP) on cytokine expression in hPDL cells.

MATERIALS AND METHODS

The hPDL cells were obtained from a healthy maxillary third molar. After the third to fourth passage, the cells were exposed to HP ranging from 1 to 6 MPa as previously described. Total RNA was extracted and the expression of cytokine mRNA was determined by RT-PCR.

RESULTS

The exposure to 6 MPa of HP caused no morphological changes of hPDL cells, and did not affect the cellular viability. No expression of IL-1beta, IL-6, IL-8, TNF-alpha, receptor activator of NF-lambdaB (RANK), receptor activator of NF-lambdaB ligand (RANKL), or osteoprotegerin mRNA was observed in the control cells under atmospheric pressure, whereas, in hPDL cells treated with HP, a pressure-dependent enhancement of IL-6, IL-8, RANKL, and OPG mRNA expression was observed between 10 and 60 min after the exposure to HP.

CONCLUSION

These results suggest that hPDL cells may play a role in the production of cytokines in response to mechanical stress in vivo.

Immunohistochemical localization of gastrin-releasing peptide receptor in the mouse brain

Gastrin-releasing peptide (GRP) is a mammalian bombesin (BN)-like peptide that binds with high affinity to the GRP receptor (GRP-R). Previous behavioral studies using mice and rats showed that the GRP/GRP-R system mediates learning and memory by modulating neurotransmitter release in the local GABAergic network of the amygdala and the nucleus tractus solitarius (NTS). To date, the precise distribution of GRP-R in the brain has not been elucidated. We used a synthetic peptide derived from mouse GRP-R to generate affinity-purified antibodies to GRP-R and used immunohistochemistry to determine the distribution of GRP-R in the mouse brain. The specificity of anti-GRP-R antibody was confirmed in vitro using COS-7 cells transiently expressing GRP-R and in vivo using GRP-R-deficient and wild-type mouse brain sections. GRP-R immunoreactivity was widely distributed in the isocortex, hippocampal formation, piriform cortex, amygdala, hypothalamus, and brain stem. In particular, GRP-R immunoreactivity was observed in the lateral (LA), central, and basolateral amygdaloid (BLA) nuclei and NTS, which are important regions for memory performance. Double-labeling immunohistochemistry demonstrated that subpopulations of GRP-R are present in GABAergic neurons in the amygdala. Consequently, GRP-R immunoreactivity was observed in the GABAergic neurons of the limbic region. These anatomical results provide support for the idea that the GRP/GRP-R system mediates memory performance by modulating neurotransmitter release in the local GABAergic network.

Comparison of mice deficient in the high- or low-affinity neurotensin receptors, Ntsr1 or Ntsr2, reveals a novel function for Ntsr2 in thermal nociception

Neurotensin (NT) is a neuropeptide that induces a wide range of biological activities including hypothermia and analgesia. Such effects are mediated by the NT receptors Ntsr1, Ntsr2 and Ntsr3, although the involvement of each receptor in specific NT functions remains unknown. To address nociceptive function in vivo, we generated both Ntsr1-deficient and Ntsr2-deficient mice. In addition, histochemical analyses of both Ntsr1 and Ntsr2 mRNAs were performed in the mouse brain regions involved in NT-related nociception. The expression of Ntsr2 mRNA was greater than that of Ntsr1 in the periaqueductal gray (PAG) and the rostral ventral medulla (RVM). The mutant and control mice were subjected to the examination of thermal nociception, and in the hot plate test, a significant alteration in jump latency was observed in Ntsr2-deficient mice compared to Ntsr1-deficient or wild-type control mice. Latencies of tail flick and hind paw licking of the mutant mice were not affected compared to control mice. These results suggest that Ntsr2 has an important role in thermal nociception compared to Ntsr1, and that these mutant mice may represent a useful tool for the development of analgesic drugs.

Scanning laser Doppler flowmeter study of retinal blood flow in macular area of healthy volunteers

AIM

To compare the interocular and intraocular differences of capillary perfusion, and the intraocular regional differences of retinal blood flow in the macular area of healthy volunteers.

METHODS

Tissue blood flow in the macula was examined in both eyes of 20 healthy volunteers with the Heidelberg retinal flowmeter. Blood flow measurements were made in a 10 degrees x 2.5 degrees area superior and inferior to the macula. The mean blood flow (MBF) was calculated by an automatic full field perfusion image analyser program. The MBF in the right and left eyes and in the superior and inferior macular areas of the same eye were compared.

RESULTS

The ratios of the MBF in the right eye to the left eye in the macular areas were 1.00, and 1.03, respectively. The ratio of the MBF in the superior macular area to the inferior area was 1.01 for the right eyes and 1.04 for the left eyes.

CONCLUSIONS

Because no significant differences were found in the MBF between the two eyes and between the superior and inferior macular areas in the same eye, interocular (for example, affected eye versus fellow eye) and intraocular (superior versus inferior macular areas) comparisons of MBF can be made to determine if changes in retinal perfusion have occurred.

Ubiquitin carboxy-terminal hydrolase L1 binds to and stabilizes monoubiquitin in neuron

Mammalian neuronal cells abundantly express a deubiquitylating enzyme, ubiquitin carboxy-terminal hydrolase 1 (UCH L1). Mutations in UCH L1 are linked to Parkinson's disease as well as gracile axonal dystrophy (gad) in mice. In contrast to the UCH L3 isozyme that is universally expressed in all tissues, UCH L1 is expressed exclusively in neurons and testis/ovary. We found that UCH L1 associates and colocalizes with monoubiquitin and elongates ubiquitin half-life. The gad mouse, in which the function of UCH L1 is lost, exhibited a reduced level of monoubiquitin in neurons. In contrast, overexpression of UCH L1 caused an increase in the level of ubiquitin in both cultured cells and mice. These data suggest that UCH L1, with avidity and affinity for ubiquitin, insures ubiquitin stability within neurons. This study is the first to show the function of UCH L1 in vivo.

Formant interaction as a cue to vowel perception: a case report

Accumulating evidence indicates that cerebral processing of consonants and vowels is separable. It has been shown that disordered temporal acuity leads to disturbed consonant perception in cases with pure word deafness. In contrast, there has been no clear explanation of how vowel perception is impaired. We examined a patient with auditory agnosia, who showed a differential ability to identify the five Japanese vowels after bilateral cerebral lesions. He correctly identified the vowel [a] in more than 70% of auditory presentations, whereas he identified [i] in only about 30% of presentations. The difference between the first and second formant frequencies "F2-F1" and an artificially defined value "F1-(F2-F1)" for each vowel correlated significantly with the percentage of correct identifications. These findings support the hypothesis that vowel perception is based on formant interactions.

Microcirculation in the macular area of eyes with an idiopathic epiretinal membrane

PURPOSE

To measure the microcirculation in the macula area of eyes before and after the removal of an idiopathic epiretinal membrane (ERM) by vitreous surgery.

METHODS

Tissue blood flow in the macula was examined with the Heidelberg retina flowmeter in 12 eyes with an ERM before and 3, 6, and 12 months after vitrectomy. Blood flow measurements were performed in a 10 x 5 degree area in the macula that was divided into superior and inferior areas. At least three measurements were obtained, and the mean blood flow (MBF) was calculated by scanning laser Doppler flowmetry. The ratio of the MBF in the affected eye to that in the fellow eye was used for statistical analysis.

RESULTS

The ratios of the MBF in the affected to the fellow eye in the superior area before and 1, 3, 6, and 12 months after surgery were 0.73, 0.51, 0.77, 0.88, and 1.01, respectively. The ratios of the MBF in the inferior area for the same periods were 0.70, 0.52, 0.75, 0.83, and 0.98, respectively.

CONCLUSIONS

Eyes with an ERM showed abnormal hemodynamics in the macula that gradually improved after vitrectomy to a status comparable with the MBF of the normal fellow eye.

Pressure distribution measurement in biting surimi gels with molars using a multiple-point sheet sensor

The bite force of three surimi gels with molars was measured in the mouth using a multiple-point sheet sensor. A peak force appeared at the breaking point of each sample, and then the force increased again, accompanied by a decrease in the opening between the upper and lower teeth. Low values in the peak force, pressure, and time at the first peak, the time at which the maximum contact area was engaged, impulse, and slope of bite curve were observed in samples with low breaking force and low breaking deformation found by the mechanical measurement of gel strength, and with less toughness in the sensory assessment. The duration of the bite force, the second peak time, and active bite pressure at the second peak did not change with a change in the surimi texture. The active pressure at the breaking point of each gel was affected by gel strength, while that at the second peak was independent of the gel strength.

[Early phase II clinical trial of amrubicin hydrochloride in patients with malignant lymphoma]

An early phase II multi-center collaborative study of amrubicin hydrochloride, a novel synthetic anthracycline derivative anticancer agent, was conducted for malignant lymphoma at 12 institutions nationwide. A total of 41 patients were enrolled in this study between January 1988 and October 1990. Of these, 36 patients, six patients with Hodgkin's disease (HD) and 30 patients with non-Hodgkin's lymphoma (NHL), were eligible for the study. The starting dose of amrubicin hydrochloride was 100 mg/m2 (body surface area) and it was administered once every three weeks, in principle. The efficacy was assessed for 34 patients, excluding two patients: one who has not been followed up adequately and the other violated the dosing schedule (once per week). The overall response rates (CR + PR) were 50.0% (3/6) for HD and 42.9% (12/28) for NHL. Furthermore, a relatively high response rate was noted in 8 (36.4%) of 22 NHL patients who had been treated with other anthracycline derivatives prior to the trial. The safety of amrubicin hydrochloride was assessed for 36 eligible patients. Leukopenia (grade 3 or higher) and thrombocytopenia were noted in 21 patients (58.3%) and 10 patients (27.8%), respectively. Anorexia, nausea/vomiting, fever, alopecia, decrease in hemoglobin and elevations of GOT and GPT levels were observed with a relatively high frequency. Other than myelosuppression, the following adverse reactions (grade 3 or higher) occurred during the course of the trial: diarrhea (two patients), alopecia (two patients), stomatitis (one patient), anorexia (one patient), nausea/vomiting (one patient) and fever (one patient). In conclusion, these results indicate that amrubicin hydrochloride is effective in the treatment of patients with malignant lymphoma.

The 5-HT1A receptor agonist 8-hydroxy-2-di-n-(propylamino)tetralin (8-OH-DPAT) induces hyperglucagonemia in rats

Effects of the 5-HT1A receptor agonist 8-hydroxy-2-di-n-(propylamino)tetralin (8-OH-DPAT) on plasma glucagon levels were investigated. 8-OH-DPAT increased plasma glucose and glucagon levels in rats. Both hyperglycemia and hyperglucagonemia elicited by 8-OH-DPAT were prevented by the 5-HT1A receptor antagonist pindolol and prior adrenodemedullation. These results suggest that increases in plasma glucagon levels induced by 8-OH-DPAT were based on the adrenaline release from the adrenal gland and its effects may contribute to its hyperglycemic effects.

The AMPA receptor allosteric potentiator PEPA ameliorates post-ischemic memory impairment

PEPA (4-[2-(Phenylsulphonylamino)ethylthio]-2,6-difluorophenoxyacetamide) is a recently developed allosteric potentiator of AMPA receptors that preferentially affects flop splice variants. We tested the effects of PEPA on ischemia-induced memory deficit in rats. Permanent unilateral occlusion of the middle cerebral artery induced severe impairment of performance of rats in the Morris water maze test. Repeated intravenous administration of PEPA (1, 3, 10 mg/kg/day for 10 days) improved test performance. In contrast, a corresponding dose of aniracetam, a representative potentiator of AMPA receptor, did not significantly improve test performance. Thus, PEPA is more effective than aniracetam in reversing impaired memory function as assessed by the Morris water maze test; and PEPA may be an effective compound for the treatment of impaired memory.

Novel cytochrome P4501B1 (CYP1B1) gene mutations in Japanese patients with primary congenital glaucoma

PURPOSE

To investigate CYP1B1 gene mutations in Japanese patients with primary congenital glaucoma (PCG).

METHODS

Sixty-five unrelated Japanese patients with PCG were screened by PCR-single-strand conformational polymorphism (SSCP) analysis followed by direct sequencing. No patients were offspring of consanguineous marriages, a common occurrence among patients in previous reports. PCG haplotypes were constructed with intragenic polymorphisms in affected individuals. Three-dimensional atomic structures of human CYP1B1 and four mutant CYP1B1 sequences representing missense mutations were assembled using homology modeling and were regularized by an energy-minimization procedure.

RESULTS

Eleven novel mutations, including seven definite and four probable mutations, were detected in 13 (20%) of the 65 unrelated patients. Of the seven definite mutations, three were predicted to truncate the CYP1B1 open reading frame. The other four were missense mutations (Asp192Val, Ala330Phe, Val364Met, and Arg444Gln), all located in conserved core structures determining proper folding and heme-binding ability of cytochrome P450 molecules. Molecular modeling demonstrated that two of four mutations in positions 330 and 364 were structurally neutral, but Arg444Gln caused significant structural change. Of the four probable mutations, three were missense (Val198Ile, Val320Leu, and Glu499Gly); the other was a base substitution in the noncoding region of exon 1.

CONCLUSIONS

The 11 varied CYP1B1 mutations found in 13 unrelated Japanese patients with sporadic occurrence of PCG represent an allelic heterogeneity and may be unique to a specific population.

Reduction of incretin-like salivatin in saliva from patients with type 2 diabetes and in parotid glands of streptozotocin-diabetic BALB/c mice

AIM

Diabetic xerostomia is a typical syndrome in diabetic complication. We have reported that salivatin (salivary peptide P-C) derived from human saliva potentiates glucose-stimulated insulin release and inhibits arginine-stimulated glucagon release. The present study is aimed to gain further evidence on the physiological role by investigating the diabetic state-induced change in the amount of salivatin.

METHODS

The amount of salivatin was measured in saliva taken from patients with type 2 diabetes with ELISA and with rabbit antiserum against human salivatin immunocytochemically in sections of parotid glands from streptozotocin-diabetic BALB/c mice.

RESULTS

The amount of salivatin after a meal was reduced by diabetes in both human saliva and in the serous secretory granule of mouse parotid gland acinar cells.

CONCLUSIONS

The above results suggest that salivatin lowers hyperglycaemia after meal and sustains the normal blood glucose levels by incretin-like mechanisms. The function may be damaged by diabetes, and this in turn might make the diabetes worse.

Lumbar posterolateral fusion alone or with transpedicular instrumentation in L4--L5 degenerative spondylolisthesis

We retrospectively reviewed 57 patients with L4--L5 degenerative spondylolisthesis (L4--L5 DS) who underwent posterior decompression and posterolateral fusion of L4--L5 without (Group A) or with (Group B) transpedicular screw instrumentation at least 2 years earlier. The clinical results and fusion rate were similar between Groups A and B, that is, a 72.4% satisfactory outcome with a fusion rate of 82.8% in Group A versus 82.1% satisfactory outcome with a 92.8% fusion rate in Group B. Screw instrumentation reduced postoperative low back pain and resulted in a lordotic slip angle of L4--L5. However, in patients with radiologically excessive segmental motion showing a translational motion of 3 mm or more, flexion angulation of -5 degrees or less, and a slip angle of -5 degrees or less at the site of spondylolisthesis (L4--L5), the kyphotic slip angle (L4--L5) tended to increase after surgery. In the future, in patients with radiologically excessive segmental motion, this point should be considered, and surgical techniques should be evaluated. Our results suggest that the validity of the general addition of screw instrumentation to L4--L5 fusion for L4--L5 degenerative spondylolisthesis is low.

New triterpenes, myrrhanol A and myrrhanone A, from guggul-gum resins, and their potent anti-inflammatory effect on adjuvant-induced air-pouch granuloma of mice

Myrrhanol A, a new triterpene isolated from guggul (Balsamodendron or Commiphora mukul Hook.)-gum resin, displays a potent anti-inflammatory effect on exudative pouch fluid, angiogenesis, and granuloma weights in adjuvant-induced air-pouch granuloma of mice. Its effects were more marked than those of hydrocortisone and the 50% aqueous methanolic extract of the crude drug. Myrrhanol A is a plausible candidate for a potent anti-inflammatory agent.

[Objective evaluation of visual field loss in a patient with branch retinal artery occlusion and brain infarction]

PURPOSE

To evaluate visual field loss using multifocal ERG(m-ERG), multifocal VEP(m-VEP), and Heidelberg Retina Flowmeter(HRF) in a patient with branch retinal artery occlusion(BRAO) and brain infarction.

CASE

A 38-year-old man noticed inferior-nasal visual field loss in the left eye, and was referred to Keio University Hospital. He suffered from paralysis in the left leg due to brain infarction at the age of 24. However, he had not noticed visual field loss due to the brain infarction. His left fundus showed retinal edema in the area of a superior-temporal retinal artery occulusion. He was diagnosed as having BRAO. The Goldmann and Humphry perimetric examinations revealed homonymous quadrantanopia in the upper left field as well as inferior visual field defect in the left eye.

RESULTS

Both m-ERG and m-VEP, especially second-kernel responses, were reduced in the affected retinal area of BRAO. But only m-VEP was affected in the corresponding area of homonymous quadrantanopia in the upper left field. The retinal flow in the area with BRAO evaluated by HRF was decreased in some areas and not in others, suggesting that retinal function was not necessarily consistent with retinal circulation.

CONCLUSIONS

m-ERG and m-VEP are useful To differentiate retinal lesions from brain lesions in visual field loss.

Synaptotagmin I expression in mast cells of normal human tissues, systemic mast cell disease, and a human mast cell leukemia cell line

Synaptotagmin I (STG I) is a Ca(2+) sensor and one of the synaptic vesicle proteins that mediate exocytosis. To determine the mechanism of release of large granules from mast cells, we studied by immunohistochemistry the presence of STG I in mast cells in normal human tissues simultaneously with the mast cell markers mast cell tryptase (tryptase) and c-kit. The tumor cells of systemic mast cell disease (SMCD) and a human mast cell leukemia cell line (HMC-1) were also examined. Human mast cells in normal tissues and the tumor cells of SMCD expressed STG I as well as mast cell tryptase (tryptase) and c-kit. STG I mRNA and its products in HMC-1 were examined by RT-PCR analysis and immunocytochemistry, respectively. STG I expression in HMC-1 cells was compared with that in cells stimulated and non-stimulated by phorbol 12-myristate 13-acetate and also with that in NB-1 and PC12 cells, known to express STG I. STG I mRNA was detected in both non-stimulated and stimulated HMC-1 cells and in NB-1 and PC12 cells. STG I immunoreactivity was weaker than NB-1 or PC12 immunoreactivity. However, it increased in the stimulated HMC-1 cells. Mast cells expressed STG I in various states. STG I may mediate exocytosis of large granules in mast cells.

Immunohistochemical localization of somatostatin receptor type 2A in rat and human tissues

In this study, we elucidated the cellular localization of somatostatin receptor (SSTR) by immunohistochemistry using an antibody specific for SSTR type 2A (SSTR2A) in various organs of rat and human. SSTR2A expression was basically similar in rat and human, except in the pancreas and adrenal cortex. In the pituitary gland, the posterior lobe and the majority of growth hormone cells and some ACTH and TSH cells expressed SSTR2A. In rat adrenal gland, the zona glomerulosa strongly expressed SSTR2A, whereas zone-specific immunoreactivity was not observed in human. The adrenal medulla moderately expressed SSTR2A in both rat and human. SSTR2A immunoreactivity was observed in islet cells and some ductal cells in human pancreas, and also in acinar cells of rat pancreas. In gastrointestinal (GI) tract, the majority of crypt cells and nerve plexuses strongly expressed SSTR2A. The number of SSTR2A positive cells was much more than that of chromogranin A positive endocrine cells. In the kidney, the glomerular capillaries and collecting tubules, but not proximal tubules, showed immunoreactivity. SSTR2A immunoreactivity was observed not only in endocrine cells but also in non-endocrine cells.

[The effect of attention on visual evoked potentials elicited by a newly designed stereogram]

PURPOSE

To investigate whether the visual evoked potentials (VEPs) obtained by a newly designed stereogram were generated by some higher function like depth perception, we examined the effect of attention on the VEPs.

SUBJECTS AND METHOD

Eight subjects participated in the experiments. The VEPs were recorded according to the international 10/20 system. The stimulus consisted of circles with or without disparity presented on 4 locations around the fixation point, and they appeared in one of 3 patterns in random order when viewed through red/green spectacles 1. at the same distance as the fixation point, 2. in front of it, or 3. at the back of it. The near pattern was defined as the target. In Experiment 1, the subjects just fixated on the fixation point. In Experiments 2 and 3, they were required to respond to the target by pressing a button and counting the number (target discrimination task).

RESULTS

A scalp negative potential with a latency of 170-280 msec was elicited in the lateral occipital area. For each of the 3 patterns the amplitude was greater in Experiments 2 and 3 than in Experiment 1. In Experiments 2 and 3, stimuli with disparity resulted in larger amplitude than without disparity. The target stimulus also evoked larger potentials than non-target stimuli did, although no such effect was apparent in Experiment 1.

CONCLUSION

Attention, as well as disparity, increased the VEPs amplitude, which indicates that the potential could be generated by neural activity higher than V 1 including depth perception. Moreover, the potential showed characteristics similar to attention-related potentials modulated by visuo-spatial attention.

[A survey of current nutrition therapy for the ALS patients in Japanese national sanatoriums]

To evaluate the current nutrition therapy for the patients of amyotrophic lateral sclerosis (ALS) in Japan, we sent questionnaires to 53 Japanese national sanatoriums (hospitals) and were able to collect replies from 42 institutes. In these replies, information on 466 patients (262 inpatients and 204 outpatients) was reported, accounting for about 10% of all Japanese ALS patients. Patients who ate orally were more frequent (p < 0.001, chi 2 test) in the outpatients (76.0%) than in the inpatients (39.7%). When the subjects were limited to non-orally nourished cases, gastrostomy was more frequently performed (p < 0.05, chi 2 test) in the outpatients (49%) than in the inpatients (29.1%), but no significant differences were observed between the above two groups as to the quantity of daily caloric intake; the mode was 1000-1200 Cal. About a quarter of non-orally nourished patients received supplemental sodium chloride, and fewer were supplemented copper and/or zinc. The consent of the patients as well as the clinical findings weighed heavily in the determination of the feeding route. Most physicians were disinclined to encourage tube feeding in the early stage of dysphagia, but were supportive of the operation of percutaneous endoscopic gastrostomy when non-oral nutrition therapy became necessary. Although the efficacy of vitamins for ALS has not been proved, 45 of 58 physicians agreed to subscribe vitamins to their patients, especially vitamin B12, E and C.

Two consecutive fasciculation potentials having different motor unit origins are an electromyographically pathognomonic finding of ALS

To electrophysiologically diagnose amyotrophic lateral sclerosis (ALS), fasciculation potentials (FPs) were evaluated in each wasted muscle in 12 ALS and 14 other neurogenic disorders (non-ALS patients). Various types of FPs were observed in ALS. The number of discharged FPs and firing rate of FPs were significantly increased in ALS compared to those in non-ALS. These findings indicate that more motor units take part in discharging FPs in ALS than in non-ALS, and that injured lower motor neurons exhibit hyperexcitability. Although nine of 12 ALS patients showed two consecutive FPs having different motor unit origins, non-ALS patients did not show such FPs. Since the two consecutive FPs having different motor unit origins reflect an involvement of both upper and lower motor neurons, these potentials are an electrophysiologically pathognomonic finding to ALS.

Vascular endothelial growth factor promotes cell-cycle transition from G0 to G1 phase in subcultured endothelial cells of diabetic rat thoracic aorta

Vascular endothelial growth factor (VEGF) has been claimed to be a major positive regulator of angiogenesis in diabetic retinopathy and atherosclerosis. Diabetic state-induced alteration of the phenotypes and the influence of 12-h pretreatment with VEGF were examined after a further 12-h treatment with only 1% fetal bovine serum in subcultured endothelial cells (EC) derived from rat thoracic aorta. By flow cytometric cell cycle analysis, VEGF showed quite different transition patterns from those of platelet-derived growth factor (PDGF) in 5-day (at the progression phase) cultured normal rat EC even though VEGF belongs to the PDGF family. VEGF promoted cell cycle transition from the G0 to the G1 phase at 3 ng/ml, but at 30 ng/ml, VEGF weakly inhibited it compared with the effect of PDGF. The streptozotocin-diabetic state promoted cell cycle transition of EC from the G0 to the G1 phase. The promotion by the low concentration of VEGF was observed even at the point of 35-day culture (angiogenic EC at the competence phase in normal state). The diabetic state enhanced EC proliferation rather than tube formation, and the tube formation was scarce. The promotion of cell cycle transition by VEGF may aggravate furthermore diabetic angiopathy due to the leaky constitution of blood vessels.

Clinical evaluation of muscle strength in 20-79-years-old obese Japanese

It is well known that obesity is closely related to non-insulin-dependent diabetes mellitus, hyperlipidemia, hypertension and cardiovascular disease, and the insulin resistance associated with obesity is supposed to play a central role for the development of these diseases. Thus, effective prevention and treatment of obesity need to be explored. In 357 obese (body mass index > or =26.4) subjects, aged 20-79 years, grip and leg strength were determined and compared with age- and sex-matched 1683 nonobese control subjects. Age-dependent alteration of body composition, evaluated by waist-hip ratio and the relative fat mass volume, was also compared. Finally, the relationship between the number of risk factors related to atherosclerosis and muscle strength was evaluated. Grip and leg strength in obese subjects were obviously stronger than controls under the age of 60 in both sexes. However, in the subjects over 60 years old, muscle strength was similar between obese subjects and controls. Weight bearing index (WBI) (leg strength (kg)/body weight (kg)) in obese subjects was remarkably lower than that in controls in all generations. In obese subjects, the waist-hip ratio and relative percentage of fat increased with aging, and obese subjects with multiple risk factors had higher waist-hip ratio and a tendency for lower muscle strength. Reduced WBI was considered to be a fundamental feature of obese subjects, and obese subjects increased fat composition with aging, which may be linked with low muscle strength. Thus, we need to design the most effective protocols to maximize and maintain quantitative and qualitative properties of muscle.

Vascular endothelial growth factor- and platelet-derived growth factor-angiogenesis depressed but fetal bovine serum-angiogenesis enhanced choroidal tissue cultures of streptozotocin-diabetic Wistar and GK rats

BACKGROUND

Diabetic state-induced alterations of angiogenic activity of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) were compared with that of fetal bovine serum (FBS) in the cultured choroidal explants of streptozotocin (STZ)-diabetic Wistar and diabetic GK rats.

METHODS

Choroidal explants (0.04-1.0 mm2) were isolated from rat eyeballs and cultured in fibrin gels with FBS-Dulbecco's modified Eagle's medium (0.5 mL) containing antibiotics and 300 microg/mL epsilon-amino caproic acid in the presence of recombinant mouse vascular endothelial growth factor and recombinant human platelet-derived growth factor BB at 37 degrees C under 5% CO2 and 95% air. Microvessels newly budded from these choroidal explants were photographed. The number and length of all microvessels per choroidal explant were counted and measured as indices of angiogenesis in vitro.

RESULTS

Fetal bovine serum (5-10%) enhanced both angiogenic indices in the explants of STZ-diabetic Wistar and GK rats. The actions of the serum on both angiogenic indices in both diabetic rats were greater than those in age-matched normal rats. Vascular endothelial growth factor (3-30 ng/mL) with 1% fetal bovine serum increased the angiogenic indices in diabetic choroids, but was less pronounced than in normal choroids. The action of the growth factor (2.5 ng/mL) on angiogenesis was also less in diabetic choroids.

CONCLUSIONS

Results suggest that the diabetic state may down-regulate the receptors for vascular endothelial and platelet-derived growth factors and/or desensitize their post-receptor signaling in the vascular endothelial cells of choroids, being inexplicable for the enhanced actions of fetal bovine serum on angiogenesis in diabetic choroids.

Immunohistochemical expression of chromogranins A and B, prohormone convertases 2 and 3, and amidating enzyme in carcinoid tumors and pancreatic endocrine tumors

Although chromogranin A (CgA) is widely distributed in neuroendocrine tumors, the distribution of chromogranin B (CgB) has not been elucidated. Hormones produced by tumors are sometimes prohormones and not necessarily bioactive hormones. Prohormones have to be processed into bioactive peptides by prohormone convertases (PCs), and some of them have to be amidated by peptidylglycine a-amidating monooxygenase (PGM). Whether PCs and PGM are present or not in tumors may explain why some tumors are functioning and some are nonfunctioning. We investigated 45 carcinoids and 16 pancreatic endocrine tumors. Of the carcinoids, CgA was expressed in most of the tumors, except for the rectal and ovarian carcinoids, which expressed CgB strongly. The expressions of PC2, PC3, and PGM were 31%, 100%, and 87%, respectively. In the pancreatic tumors, CgA was expressed in all tumors, whereas CgB was not expressed in any tumor. The expressions of PC2, PC3, and PGM were 63%, 88%, and 63%, respectively. PC3 was expressed in all of the functioning tumors but not in two of the four nonfunctioning tumors. PC2 and PGM were not expressed in three of the four nonfunctioning tumors. In conclusion, expression of CgA and CgB was different depending on the tumor location. High frequency of PCs and PGM may explain why even nonfunctioning tumors produce some inconspicuous peptides.

Arachidonic acid and prostaglandin D2 cooperatively accelerate desensitization of nicotinic acetylcholine receptor channel in mouse skeletal muscles

To clarify the effects of arachidonic acid (AA) and its metabolites on desensitization of nicotinic acetylcholine (ACh) receptor channel in mouse skeletal muscle cells, we investigated the time-dependent decrease in the channel opening frequency of ACh (1 microM)-activated channel currents by the cell-attached patch clamp technique. AA (30-100 microM) applied to a patched membrane or to non-patched membrane accelerated the decrease in the channel opening frequency. A cyclooxygenase inhibitor, indomethacin (10 microM), prevented the acceleration elicited by 30 microM AA, but not by 100 microM AA. A lipoxygenase inhibitor, nordihydroguaiaretic acid (10 microM), and a cytochrome P-450 inhibitor, ketoconazole (3 microM), did not affect the acceleration by 30 microM AA. Prostaglandin (PG) D2 at 10 microM alone and at 25 nM in combination with 10 microM AA accelerated the decrease in the channel opening frequency. No acceleration was observed with PGE2 at 10 microM alone and at 25 nM in combination with 10 microM AA. Pretreatment with a protein kinase (PK) C inhibitor, staurosporine (10 nM), but not with a PKA inhibitor, H-89 (3 microM), prevented the acceleration elicited by AA + PGD2. These results suggest that AA, and PGD2 of its metabolites, cooperatively accelerate desensitization of nicotinic ACh receptor channel. The activation of PKC by AA and PGD2 may be involved in the mechanism of the cooperative acceleration of desensitization.

Antihyperglycemic effects of gymnemic acid IV, a compound derived from Gymnema sylvestre leaves in streptozotocin-diabetic mice

We investigated the antihyperglycemic action of a crude saponin fraction and five triterpene glycosides (gymnemic acids I-IV and gymnemasaponin V) derived from the methanol extract of leaves of Gymnema sylvestre R. BR. (Asclepiadaceae) in streptozotocin (STZ)-diabetic mice. The saponin fraction (60mg/kg) reduced blood glucose levels 2 4h after the intraperitoneal administration. Gymnemic acid IV, not the other 4 glycosides at doses of 3.4-13.4mg/kg reduced the blood glucose levels by 13.5-60.0% 6h after the administration comparable to the potency of glibenclamide, and did not change the blood glucose levels of normal mice. Gymnemic acid IV at 13.4 mg/kg increased plasma insulin levels in STZ-diabetic mice. Gymnemic acid IV (1 mg/mL) did not inhibit alpha-glycosidase activity in the brush border membrane vesicles of normal rat small intestines. These results indicate that insulin-releasing action of gymnemic acid IV may contribute to the antihyperglycemic effect by the leaves of G. sylvestre. Gymnemic acid IV may be an anti-obese and antihyperglycemic pro-drug.

Release of endothelins and platelet-activating factor by a rat pleural mesothelial cell line

Thrombin is a multifunctional serine protease. It is generated in inflammatory processes and induces the proliferation and chemotaxis of a variety of cells including mesothelial cells (MTCs). MTCs are epithelial cells derived from the mesoderm, as are the vascular endothelial cells. Since thrombin acts on endothelial cells to produce platelet-activating factor (PAF) and endothelin (ET)-1, it was hypothesized that MTCs also produce PAF and ET via the action of thrombin. Rat pleural MTC (RMTC, 4/4 R.M.-4) monolayers were cultural in tissue culture dishes for various periods. The supernatants were fractionated by means of high-performance liquid chromatography to determine the ET isoforms and PAF species present. Immunoreactive ET was measured using an enzyme-linked immunosorbent assay, and PAF was measured by means of a bioassay using a platelet aggregometer. ET-1, ET-2 and ET-3 were detected in RMTC-conditioned medium, and the predominant isoforms were ET-1 and ET-2. RMTCs mainly released C16:0 PAF into the supernatant. Immunoreactive ET and PAF were released via the action of thrombin. Synthetic PAF significantly induced secretion of ET, but the PAF receptor antagonists, WEB2086 and E6123, failed to modulate thrombin-induced ET release. These results indicate that thrombin acts on pleural rat mesothelial cells to release ET and PAF, which may play a role in the development of pleurisy.