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Vertebrates usually exhibit gonochorism, whereby their sex is fixed throughout their lifetime. However, approximately 500 species (~ 2%) of extant teleost fishes change sex during their lifetime. Although phylogenetic and evolutionary ecological studies have recently revealed that the extant sequential hermaphroditism in teleost fish is derived from gonochorism, the evolution of this transsexual ability remains unclear. We revealed in a previous study that the tunica of the ovaries of several protogynous hermaphrodite groupers contain functional androgen-producing cells, which were previously unknown structures in the ovaries of gonochoristic fishes. Additionally, we demonstrated that these androgen-producing cells play critical roles in initiating female-to-male sex change in several grouper species. In the present study, we widened the investigation to include 7 genera and 18 species of groupers and revealed that representatives from most major clades of extant groupers commonly contain these androgen-producing cells, termed testicular-inducing steroidogenic (TIS) cells. Our findings suggest that groupers acquired TIS cells in the tunica of the gonads for successful sex change during their evolution. Thus, TIS cells trigger the evolution of sex change in groupers., Scientific Reports, 11, art. no. 11117; 2021

This study characterizes the spawning phenomena of the honeycomb grouper (

Solid-state organic fluorescent materials are important for the development of electroluminescent sensing devices. Herein, we report that N,N′-bis((R)-1-phenylethyl)perylene-3,4,9,10-tetracarboxylic diimide [(R,R)-BPP] and its antipode [(S,S)-BPP], which contain extended π-electrons through planar perylenes, emit solid-state aggregation-induced-enhanced (AIEnh) circularly polarised luminescence (CPL) in inorganic (KBr) pellets and organic-polymer-film (PMMA- and myo-IPU-film) states; this CPL is difficult to observe in solution. These chiral perylene fluorophores emit AIEnh-CPL with high dissymmetry factors (gCPL) (up to 2.4 × 10−3) and high quantum yields (ΦF, up to 0.43) in the three solid matrices.

The subtypes of zona pellucida (zp), primarily expressed in female gonads, are considered novel molecular markers for testis-ova (or intersex), a type of gonadal abnormality caused by environmental estrogens (EEs) in Japanese medaka (Oryzias latipes). However, the association between testis-ova and the expression of gonadal zp subtypes is unclear in other teleost species, particularly in species studied in field surveys. In this study, 17α-ethinylestradiol (EE2) was orally administrated at 4–4000 ng/g body weight (BW)/day for 28 days to gray mullets (Mugil cephalus), and gonadal abnormalities were studied using histological analysis. The expression profiles of gonadal zp subtypes (zpb and zpc5) were analyzed to evaluate their suitability as gonadal abnormality markers by comparing with a hepatic vitellogenin (vtg) subtype (vtgAb). The oral administration of EE2 40 and 400 ng/g BW/day for 28 days induced significant gonadal zpb expression, and the gonads showed moderate abnormality (testis-ova). Conversely, the gonadal zpc5 levels decreased significantly in response to the oral administration of EE2 at 4000 ng/g BW/day for 28 days, and the gonads exhibited severe abnormalities. The hepatic vtgAb levels increased upon EE2 treatment regardless of gonadal abnormality. Therefore, the gonadal zpb levels and hepatic vtgAb levels served as appropriate markers for testis-ova and EE2 presence, respectively. However, the diagnosis of severe gonadal abnormality using gonadal zpc5 was moderately accurate. The findings suggest that the combination of vtgAb, zpb, and zpc5 is a potential marker for gonadal abnormality caused by EE contamination in gray mullet. That said, the potential of zpc5 should be reconsidered to determine if it shows greater accuracy in a larger or more diverse population.

Gonadotropin-releasing hormone (GnRH) is one of the most important neuroendocrine regulators for animal reproduction. GnRH-like peptide (GnRH-like)has recently been shown to play a critical reproductive role mainly in gametogenesis or steroidogenesis in the gonads of some molluscs, including cephalopods. However, its involvement in gonadal sex differentiation remains unknown. Here, we show the expression profile of GnRH-like in the brain of the cephalopod kisslip cuttlefish, Sepia lycidas, throughout gonadal sex differentiation, by quantitative real time RT-PCR and immunohistochemistry. We found that GnRH-like could be detected in the brain at a sexually undifferentiated stage, and its expression level significantly increased upon initiation of gonadal sex differentiation. However, no significant difference in GnRH-like expression levels was observed between sexes during gonadal sex differentiation. Additionally, we demonstrated immunoreactivity of GnRH-like in glial cells or immature neurons, which are mainly distributed in the non-reproductive related area of the cephalopod brain, suggesting the immature function of the reproductive endocrine axis during early ontogenesis. Our results demonstrate for the first time, the expression profile of GnRH-like during early ontogenesis in cephalopods., General and Comparative Endocrinology, 304, art.no.113718; 2021

In polymer electrolyte fuel cells (PEFCs), an enhancement of oxygen transport with excess water removal in membrane electrode assemblies can lead to better cell performance especially in high current density operation. Controlling porous structure in the catalyst layers is of great concern, satisfying these demands as well as achieving less precious catalyst loading and reduction of overpotential that are necessitated for automobile application of PEFCs. Depositing and engineering the catalyst layers have been gathering much attention intensively in these two decades [1-2]. Porous electrodes in PEFCs are generally fabricated by either coating or spraying the electrode slurry on substrate materials. Mixing, coating and drying processes of the slurry inherently affect the structural formation of the porous electrode and thus cell performance [3]. In this study, we focused our attention on the inkjet printing technique as a versatile method to control catalyst layer structure. Catalyst layers (CL) with micro-grooves, which potentially provide liquid water channels in the electrodes, were fabricated by adjusting an electrode slurry injectable from a single capillary nozzle in a printing device (Fig.1). Catalyst layers made by a decal transfer technique were also prepared for comparison. The catalyst layers prepared by each method were controlled to gain the same amount of contents, i.e. platinum, ionomer and carbon, within 5% variation. Porous structure and cell polarization of each catalyst layer were examined. A two-stage ion-beam method using ion milling and focused ion beam (FIB) [4] was applied to analyze the spatial distribution of both ionomer and pore in the catalyst layers as shown in Fig.1. In this technique, a relatively wide cross-section of the CL was firstly formed by a broad ion beam and then, the ionomer impregnated in the CL was removed selectively by a focused ion beam. It was revealed that the electrode thickness was affected by fabrication methods, presumably due to mixing and coating processes. Cell performance shows its variation, depending on fabrication methods and this suggests an optimized electrode structure for further cell performance improvements. Acknowledgements This work was supported by JSPS KAKENHI Grant Number 18H01383. References [1] A. Strong, C. Thornberry, S. Beattie, R. Chen, S. R. Coles, J. Fuel Cell Sci. Technol., 12(6), (2015), 064001. [2] M. Breitwieser M. Klingele S. Vierrath R. Zengerle, S. Thiele, Adv. Energy Mater., 8, (2018), 1701257. [3] T. Suzuki, S. Tsushima, S. Hirai, Int. J. Hydrogen Energy, 36(19), (2011), 12361. [4] T. Suzuki, T. Koyama, S. Tsushima, ECS Trans., 80(8), (2017), 419-423.. Figure 1

Reduction of energy consumption is one of the recent key topics in railway sector. There are many investigations such as SiC devices, permanent magnet motors, onboard and stationary energy storage and reversible substations to absorb regenerative braking, energy efficient driving and traffic management. Multi-train simulators play an important role in evaluating the effect of these countermeasures. In the simulator, power feeding circuit must be modeled to calculate the energy consumption with high accuracy. There are some literatures of modeling and solving feeding circuits, however most of them linearized some nonlinear but important characteristics of trains and substations. We have also proposed a methodology of precise modeling and solving power feeding circuits of railway systems implemented in the multi-train simulator. The methodology is flexible and characterized by the special node numbering and introduction of ‘tie nodes’ which is solvable by multipurpose solvers. In this paper, we analyze the solvability of the methodology and introduce the virtual ‘tie nodes’ to decrease errors of circuit equation if the distance of two nodes is very near. The criterion whether the virtual tie node should be used or not is finally analyzed.

Grouper culture assumes importance like any other economically important food fish aquaculture practice in Japan. Regular availability of sexually mature brood stock at appropriate time and stable seed production are considered vital for prolific fish farming. Despite the fact that previous studies have induced sexual maturation and spawning in some grouper species that had ovaries with vitellogenic or full-grown mature oocytes, little attention has been paid to artificial induction of sexual maturation and spawning of immature fish in off-spawning season. Developing such a method will promote grouper aquaculture immensely. In an aim to facilitate such a task, we used one of the popular experimental model fishes, the honeycomb grouper, Epinephelus merra , to induce sexual maturation during non-breeding season by modulating environmental factors with gonadotropin-releasing hormone analogue (GnRHa) implantation using osmotic pump. We performed three different experiments flanking various periods of non-breeding season under artificial/natural photothermal conditions with or without GnRHa implantation. Induction of sexual maturation is scored by the presence of vitellogenic to mature oocytes after various treatments in addition to the data of gonado-somatic index and plasma estradiol levels. Among various treatments, high water temperature with long photoperiod conditions induced sexual maturation in immature groupers during October to December. Implantation of GnRHa to these fishes induced sexual maturation at all periods of non-breeding season tested in this study. In fact some of the fishes belonging to these groups have even spawned during the course of treatment indicating the effectiveness of the treatments. On the other hand, neither GnRHa implantation alone nor exposure to natural photothermal conditions evoked sexual maturation. Likewise, combination of short and long photoperiod with low to high water temperature exposure over the duration period was found to be least effective with or without GnRHa implantation. Similarly, exposure to long photoperiod or high water temperature alone did not induce sexual maturation. Hence, combination of artificial photothermal conditions with GnRHa implantation seems to be a decisive method to induce sexual maturation in immature fish. Based on these results, we demonstrate a superior strategy for successful breeding of sexually immature marine teleost fish during non-breeding season by modulating environmental variables with GnRHa implantation.

To understand the mechanism of sex differentiation in the protogynous Malabar grouper Epinephelus malabaricus, we performed an immunohistochemical investigation of the expression of three steroidogenic enzymes, cholesterol-side-chain-cleavage enzyme (CYP11a), aromatase (CYP19a1a), and cytochrome P45011beta-hydroxylase (CYP11b), in the gonads during ovarian differentiation. Strong positive immunoreactivity against CYP11a, the key enzyme of steroidogenesis, and CYP19a1a which is essential for estrogen (17beta-estradiol) production, appeared first in the somatic cells surrounding gonial germ cells in undifferentiated gonads and throughout ovarian differentiation. However, positive immunoreactivity against CYP11b, which is important for androgen (11-ketotestosterone) production, first appeared in the cluster of somatic cells in the ovary tunica near the dorsal blood vessel after differentiation. CYP19a1a and CYP11b did not co-localize in any cells. These results indicate that there are two types of steroid-producing cells, estrogen-producing cells and androgen-producing cells, in the gonads of this fish, and they are distributed differently, suggesting that these cells are derived from different somatic cells. Estrogen-producing cells appeared prior to ovarian differentiation, while androgen-producing cells were first detected after ovarian differentiation. These results suggest that endogenous estrogen is involved in ovarian differentiation.

The Malabar grouper Epinephelus malabaricus is an important candidate species for commercial aquaculture in tropical and subtropical areas. In nature, this species requires more than 10 years to change sex from female to male and have active spermatogenic tissues in the testis. Thus, it is essential to find a means of producing sperm for seed production. This is the first report of artificial sex change in underyearling E. malabaricus. Female E. malabaricus with immature ovaries at 144 days post-hatch (DPH) were fed a diet with 17α-methyltestosterone (MT) at 50 μg g−1 diet for 6 months. Sex change occurred in most of the treated fish, which had testis with all stages of spermatogenic germ cells including spermatozoa. In contrast, most of the control fish had immature ovaries. These results, which reveal that germ cells in the underyearling grouper have the ability to produce spermatozoa in response to exogenous androgen, demonstrate that sex change can be artificially induced during ovarian development.

To obtain basic information on sex differentiation in groupers, the process of gonadal sex differentiation in the Malabar grouper, Epinephelus malabaricus, was followed using histology for one year from hatching. Gonads of fish less than 39 days post-hatch (DPH) were undifferentiated and consisted of a few germ cells surrounded by somatic cells. There were no morphological indications of sex differentiation at this stage. By approximately 47 DPH, however, two elongations of somatic cells had formed in the gonads on the sides facing the gonad lateral walls. These elongations correspond morphologically to the initiation of ovarian cavity formation, a characteristic of ovarian differentiation in other teleost fish. By 74 DPH, the elongations had developed further and were evident in the ovaries of all fish. However, by 144 DPH, ovarian germ cells had not yet begun active division. Oocytes were first evident in the ovaries at 243 DPH, distributed mainly within the somatic tissue on the distal sides of the ovaries facing the ovarian cavity. The oocytes increased in number and in size from 243 to 360 DPH. These observations demonstrate that morphological changes associated with ovarian differentiation in the Malabar grouper begins at approximately 47 DPH and that in all individuals the gonads differentiate directly into ovaries.

To clarify the cause of sex change recovery after the withdrawal of androgen treatment, immature female Malabar grouper were fed a diet containing 17alpha-methyltestosterone (MT) at 50 μg/g for 7 mo and then a normal diet for 6 mo. The MT brought about precocious sex change from immature ovaries to mature testes with active spermatogenesis, including the development of spermatozoa, and sex change reversed soon after MT treatment withdrawal. This result indicates that precocious sex change in immature Malabar grouper with oral MT treatment is impermanent. The expression of three steroidogenic enzymes (Cyp11a, Cyp19a1a, and Cyp11b) in the gonads of the Malabar grouper were analyzed immunohistochemically at the end of the 7-mo treatment. No apparent differences were seen in the expression pattern of these enzymes between the mature testes of MT-treated fish and the immature ovaries of control fish. In addition, serum estradiol-17beta and 11-ketotestosterone levels in treated fish were the same as those in control fish. These results indicate that in the case of immature Malabar grouper MT might have little effect on endogenous steroidogenesis during precocious sex change even though it induced active spermatogenesis in the gonads of treated fish. From these results, we also concluded that MT might have little effect on the steroidogenic endocrine pathway, and this is one cause of sex change recovery after treatment withdrawal.

Two sibling viruses of the subacute sclerosing panencephalitis (SSPE) virus Osaka-2 strain were isolated from a small biopsy specimen of the brain of an SSPE patient just before intraventricular interferon treatment by cocultivation with two different cell lines, Vero cells or B95a cells (Ogura et al, 1997). Both the virus-infected cells were found to be indistinguishable from each other in defective production of cell-free virus and in defective expression of the matrix (M) protein. The sequence analysis of the M genes predicted that they were translatable due to a lack of alteration of the translational start and stop codons for the proteins. A different pattern of the M monocistronic transcripts, however, was observed in a Northern blot analysis of the infected cells. This different pattern was confirmed further by a primer extension analysis. The undetectable expressions of the M proteins in the sibling virus-infected cells are most probably different in their molecular mechanisms. All these results indicate the possibility that the two different, replicable variants existed at Jabbour stage III of the disease's progression in a very small portion of the brain, where no lesion had yet been recognized by a magnetic resonance imaging.

The Fr/V and Oc/V sibling viruses of the Osaka-1 strain of the subacute sclerosing panencephalitis (SSPE) virus were defective in cell-free virus production. By radioimmunoprecipitation assay, the matrix (M) protein was not detected in cells persistently infected with the Osaka-1 strain. This undetectable expression was consistent with the selective reduction of antibody response to the M protein in the patient from whom the Osaka-1 strain was isolated. The sequence of the M gene, however, predicted that the protein could be synthesized because the translational start and stop codons for the protein were not altered. Northern blot hybridization demonstrated the selective defect of the monocistronic mRNAs for the M protein and the phosphoprotein (P) together with the dominant presence of the P-M bicistronic mRNA. This absence of the M mRNA was further confirmed by primer extension analysis. Therefore, the undetectable expression of the M protein in the infected cells was proved to be caused by a transcriptional defect. The two sibling viruses, isolated from remote portions of an SSPE brain, were indistinguishable in their viral characters, including the M gene sequences, which indicates the possibility of clonal expansion of the strain in the brain.

A 2-year-old girl, who had prolonged thrush and spastic diplegia, was found to have a mother-to-child vertical transmission of human immunodeficiency virus type-1 (HIV). A brain computed tomography scan revealed a symmetrical calcification on the bilateral basal ganglia and periventricular white matter. She had an acquired immune deficiency syndrome (AIDS) encephalopathy of pure dominant pyramidal tract disorder without an intellectual deficit. Helper cell lymphocyte count (CD4) increased with the beginning of zidovudine (ZDV, also known as AZT) monotherapy but began to decrease after the 4th week to reach the baseline at 20th week. Zidovudine plus didanosine combination therapy was started at the 68th week, but because of intolerance, the combination was changed to ZDV plus lamivudine at the 98th week. By the 80th week, neither severe opportunistic infection nor deterioration of the neurological status was recognized, but chronic diarrhea appeared. The diarrhea advanced to the wasting syndrome at the age of 4 years and cytomegalovirus genome was confirmed in a biopsied specimen of the colon. Ganciclovir treatment was effective in stopping the diarrhea and increasing her bodyweight, but after the age of 5, resumption of diarrhea was followed by progressive emaciation and weakness. This work may provide some clues in treating children's AIDS.

Measles viruses isolated from brain cells of patients with subacute sclerosing panencephalitis (SSPE) have numerous mutations, especially in the matrix protein (M) gene. To find whether the M genes of these SSPE viruses were mutated randomly or in a pattern, we sequenced this gene from three strains of defective measles virus isolated in Osaka, Japan. We could deduce the sequence of the possible progenitor measles virus for each patient by comparison of the isolate with measles viruses prevailing at roughly the same time and place as the primary infection. Biased hypermutation affected the M genes of all three SSPE viruses, although the molecular mechanisms for the mutations might be various. Replacements of U with C in the plus strand accounted for 76% of all mutations in two of the strains, but in the other strain, replacements of A with G accounted for 52% of the mutations, and the U residues were unchanged.

Subacute sclerosing panencephalitis virus has been isolated with difficulty from brains of infected patients. More strains are needed for the study of the pathogenesis of this virus. To make the isolation more efficient, we selected portions to be examined from the brains of three patients with reference to findings of repeated magnetic resonance and computed tomographic imaging. Three cell lines susceptible to measles virus field strains were used. In all three cases viruses were isolated most effectively from recent lesions and with Vero cells. Our results suggested that these imaging methods and Vero cells could be used for improvement in the efficiency of isolation of this virus from patient brains.

We recorded entorhinal tetanic responses to 50-Hz kindling stimulations applied at the amygdala in conscious rats, which produced facilitation and depression during the train pulses, in order to analyze the relationship of the changes in the tetanic responses to the development of both after-discharges (ADs) and behavioral seizures. Facilitation was always produced in the earlier tetanic responses and was followed by depression which reached a quasi-steady level in the later tetanic responses during each kindling stimulation. To estimate the changes in magnitude of the excitatory synaptic activation in the tetanic responses, with reference to the development of seizure stages, tetanic responses which produced the same behavioral seizure stage in each rat were averaged and the area between the negative (excitatory) potentials and the baseline of the averaged tetanic response was measured in terms of mV x ms. Magnitudes of the averaged negative components were significantly enhanced with an increase in the order of seizure stages in eight rats (P < 0.01). In addition, the mean magnitude of the averaged negative components had a linear correlation (r = 0.95, P < 0.05) with the mean AD duration with reference to the order of seizure stages in the eight rats. The magnitude of the positive (inhibitory) component in the averaged tetanic responses was also measured and found to decrease with an increase in the seizure stages (P < 0.01). The magnitude of the negative component in the test responses to single (0.3 Hz) stimuli just before kindling stimulations also increased with an increase in the order of seizure stages, indicating long term potentiation of the responses by kindling stimulations. We concluded from the results that the enhancement of facilitation of the excitatory synaptic activation and the reduction of the inhibitory synaptic activation in entorhinal tetanic responses by 50-Hz amygdala kindling stimulation is involved in the electrophysiological source of the progression of kindling epilepsy.

We investigated the relationship between the progress of afterdischarges (AD) and the development of facilitated entorhinal tetanic responses by amygdala kindling stimulations in conscious and pentobarbital (PB)-treated rats. The entorhinal responses consisted of deep negative components and the following shallow positive components. The negative potential (mean +/- SE) reflecting excitatory synaptic activation in the test response evoked by a single stimulation (600 microA) before kindling stimulations was greater in PB-treated rats (1.3 +/- 0.21 mV, n = 6) than in conscious rats (0.5 +/- 0.08 mV, n = 9). The positive potential reflecting inhibitory synaptic activation in the test response was also greater in PB-treated rats (0.6 +/- 0.14 mV, n = 6) than in conscious rats (0.2 +/- 0.04 mV, n = 9). The magnitude of the tetanic response was estimated as the area between the excitatory negative potential and the baseline in the averaged tetanic response during each kindling stimulation (10 Hz, 100 pulses). The magnitude of the tetanic response was significantly enhanced in association with the prolongation of AD duration in the conscious rats. In the PB-treated (50 mg/kg intraperitoneally, i.p.) rats, enhancement of tetanic response was very slight and the progress of AD duration was prevented. There was a linear correlation (r = 0.9) between the magnitude of tetanic response and AD duration. These findings indicate that PB suppresses kindling-induced enhancement of excitatory synaptic activation in tetanic responses and that this enhancement is intimately related to the development of AD.

The aim of this study was to clarify the roles of 2 gonadotropins (GTHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), on sex differentiation in the protogynous Malabar grouper, Epinephelus malabaricus. To do this, the mRNA expression patterns of GTH subunits (cga, fshb, and lhb) in the fish pituitary throughout gonadal sex differentiation were investigated. Real-time reverse transcriptase (RT)-PCR showed that cga and fshb were present in the undifferentiated and ovarian differentiation stages, and that the expression levels significantly increased after ovarian differentiation (AOD). However, lhb was not expressed before ovarian differentiation (BOD) and was first detected AOD. Next, to investigate the differentiation and distribution of Fshb and Lhb-producing cells in the pituitary of fish throughout gonadal sex differentiation, immunohistochemical analysis was used to detect teleost GTH subunits. Positive immunoreactivity against Fshb and Lhb was not detected in the pituitary BOD; Fshb and Lhb-positive cells first appeared in the pituitary AOD. It therefore seems unlikely that pituitary gonadotropins play a major role in the control of gonadal sex differentiation in the Malabar grouper.

Changes in synaptic potentials during each train stimulation (tetanic responses) have been suggested to intimately relate to the development of kindling. We examined the effects of an NMDA antagonist, carboxypiperazinephosphonate (CPP), and a GABAergic antagonist, picrotoxin, on entorhinal tetanic responses evoked by train stimuli (10 Hz, 100 pulses) at the developmental stage (seizure stage; 0–2) of amygdala kindling in conscious rats, to clarify the significance of facilitation in tetanic responses and the roles of NMDA and GABA receptors in the development of kindling. Facilitation of tetanic responses was noted as a progressive increase in both amplitude and duration of negative potentials in the tetanic responses, especially during the later half of train pulses (51–100). The negative potential area (mV × ms) of the averaged tetanic responses was used as an estimate of the magnitudes of excitatory synaptic activity in the tetanic responses, and correlated significantly (P < 0.001) with the duration of afterdischarges (AD). CPP (10 mg/kg) reversibly blocked AD in association with a significant decrease (P < 0.05) in the negative potential area. The CPP-sensitive component consisted of a slow negative potential with a duration longer than 60 ms and was greater in the later tetanic responses (51–100) than the earlier ones (1–50). Picrotoxin (2–3 mg/kg), which did not produce convulsions, significantly (P < 0.005) increased the negative potential area in the tetanic responses in association with a reversible decrease in the AD threshold. Although positive potentials ascribable to inhibitory synaptic activity were often negligible in the tetanic responses in controls, picrotoxin further decreased the positive potentials of tetanic responses, if any. We suggest from these results that facilitation of entorhinal tetanic responses during amygdala kindling stimulation is enhanced by NMDA-receptor activation and reduction of GABAergic inhibition, and that both NMDA and GABA receptors are responsible for the electrophysiological origin of the development of kindling.

We report a 20-month-old girl with an unruptured aneurysm of the middle cerebral artery. The initial sign was complex partial seizures. Magnetic resonance angiography showed an aneurysm of the right middle cerebral artery. Cerebral angiography confirmed the presence of a saccular aneurysm. After 3 months, the aneurysm spontaneously thrombosed without neurological deficit. The seizures were controlled by anti-convulsants. The aneurysm was probably near the focus of the complex partial seizures. This is a rare case of a childhood cerebral artery aneurysm that first manifested itself by complex partial seizures.

The three-spot wrasse (Halichoeres trimaculatus), which inhabits the coral reefs of Okinawa, changes sex from female to male. Sex change in this species is controlled by a social system. Oocytes disappear completely from the ovary, and male germ cells and somatic cells comprising testicular tissue arise a new during the sex change process. However, little is known of the fate and origin of the gonadal tissue-forming cells during sex change. In particular, the fate of ovarian somatic cells has not been determined, although the ovarian tissue regresses histologically. To approach this question, we analyzed apoptosis and cell proliferation in the sex-changing gonads. Unexpectedly, we found that few apoptotic somatic cells were present during sex change, suggesting that ovarian somatic cells might survive during the regression of the ovarian tissue. On the other hand, cell proliferation was detected in many granulosa cells surrounding the degenerating oocytes, a few epithelial cells covering ovigerous lamella and a few somatic cells associated with gonial germ cells at an early stage of sex change. Then, we found that proliferative ovarian somatic cells remained in the gonads late in the sex change process. Based on these results, we concluded that some functional somatic cells of the ovary are reused as testicular somatic cells during the gonadal sex change in the three-spot wrasse.

A sufficient supply of NADPH is a critical factor in l -lysine production by Corynebacterium glutamicum . Endogenous NAD-dependent glyceraldehyde 3-phosphate dehydrogenase (GAPDH) of C. glutamicum was replaced with nonphosphorylating NADP-dependent glyceraldehyde 3-phosphate dehydrogenase (GapN) of Streptococcus mutans , which catalyzes the reaction of glyceraldehyde 3-phosphate to 3-phosphoglycerate with the reduction of NADP + to NADPH, resulting in the reconstruction of the functional glycolytic pathway. Although the growth of the engineered strain on glucose was significantly retarded, a suppressor mutant with an increased ability to utilize sugars was spontaneously isolated from the engineered strain. The suppressor mutant was characterized by the properties of GapN as well as the nucleotide sequence of the gene, confirming that no change occurred in either the activity or the basic properties of GapN. The suppressor mutant was engineered into an l -lysine-producing strain by plasmid-mediated expression of the desensitized lysC gene, and the performance of the mutant as an l -lysine producer was evaluated. The amounts of l -lysine produced by the suppressor mutant were larger than those produced by the reference strain (which was created by replacement of the preexisting gapN gene in the suppressor mutant with the original gapA gene) by ∼70% on glucose, ∼120% on fructose, and ∼100% on sucrose, indicating that the increased l -lysine production was attributed to GapN. These results demonstrate effective l -lysine production by C. glutamicum with an additional source of NADPH during glycolysis.

Entorhinal field potential with amygdala stimulation in suckling (16–18 days old) and adult rats was recorded with a tungsten wire electrode (tip diameter 2–5 μm) to study the developmental changes in behavioral seizures and long-term potentiation (LTP) in the responses to amygdala kindling stimulations. Stimulating (twisted enamel-coated wires) and recording electrodes were implanted in anesthetized rats 2–3 days before kindling. The mean amplitude of the responses to test pulses (600 μA, 0.3 Hz) in the sucklings (0.58 mV) was smaller than in the adults (1.32 mV), and latency was about 3.3 ms longer. Kindling stimulations consisted of 0.5-ms monophasic rectangular pulses of 10 Hz with a 10-s train duration; the intensity was the afterdischarge (AD) threshold. Kindling stimulation in the sucklings usually increased the amplitude of the test responses evoked 10 min or 1 h after the kindling stimulation. The increased amplitude persisted for at least 24 h, showing LTP in the synaptic transmission. The LTP was especially prominent in the first kindling stimulation, and the LTP gradually increased with successive stimulations, with gradual progression of AD and the behavioral seizure stage as well. The mean number of kindling stimulations to cause generalized seizures in the suckling rats (10.5) was less than that for adults (12.5), and the continued evolution of LTP over the course of kindling was more or less easier in the sucklings than in the adults. The LTP in kindled suckling rats was observed for all intensities of test pulses and the input—output (I/O) curve in the kindled rats was significantly higher (P

Most subacute sclerosing panencephalitis (SSPE) viruses, including our Osaka-1, -2, and -3 strains isolated in Osaka, have shown negative hemadsorption (HAD) by African green monkey red blood cells. This property has been thought to be characteristic of SSPE virus as compared to the positive reaction of the standard Edmonston strain of measles virus (MV). However, this assumption has become quite obscure because MV mutates frequently at the genetic level during its multiplication and also because recent field strains isolated by lymphoblastoid cell lines have shown negative HAD. To investigate the above issue, the nucleotide sequences of the hemagglutinin (H) genes from SSPE virus Osaka-1, -2, or -3 strains were compared to those of various MV field strains isolated in Osaka by Vero cells. The H gene sequences of three SSPE strains were relatively conserved without such biased hypermutation as had been observed in the matrix (M) gene of three SSPE strains. However, this analysis of the H gene sequence of the SSPE viruses enabled us to deduce possible progenitor MVs, which are in agreement with the deduction from the M gene analysis we reported previously. The HAD of Vero cells transfected with the cloned H cDNAs from the SSPE strains and their progenitors suggested that negative HAD of the SSPE viruses has been maintained as one of original properties of the progenitor MVs rather than having been acquired as an altered one during long-term persistent infection in the brains of patients with SSPE.

We report on a 3-year-old girl with respiratory syncytial virus (RSV) encephalitis manifested by disturbance of consciousness, conjugate eye deviation, anuria, truncal ataxia and intention tremor. T2-weighted magnetic resonance imaging (MRI) showed hyperintense areas in the cerebellar cortex. No lesion was detected in the cerebral cortex, pons or spinal cord. The hyperintense areas in the cerebellar cortex diminished with recovery from the clinical manifestations and had resolved 2 months after onset. The MRI lesions in the cerebellum were considered to be due to oedema. SPECT and positron emission tomography (PET), performed 3 months after onset, disclosed areas of hypoperfusion and hypometabolism at the same sites. One year after onset, MRI showed mild atrophy of the cerebellum. Hypoperfusion on SPECT and hypometabolism on PET remained. Neuroimaging showed that ataxia and tremor in this case were the result of cerebellitis. The patient has no neurological deficit except for mild truncal ataxia. This patient is a rare example of RSV encephalitis.

The effect of hyperthermia on excitatory synaptic transmission in the hippocampal CA1 area in response to contralateral CA3 stimuli at 23-26 days of age and the influence of hyperthermia-induced seizures (HS) on the kindling phenomenon induced by CA3 stimulation at 27-29 days of age were investigated in developing rats. When hyperthermia (43.6 +/- 0.5 degrees C) did not induced seizures in conscious unrestrained rats, transient (1 h) potentiation was observed in electrically evoked synaptic responses (EPSP and population spikes). When generalized seizures were induced by hyperthermia (43.3 +/- 0.4 degrees C), long-term potentiation (LTP) was observed over 24 h. The difference in time course of the potentiation depended on whether high-voltage multispikes on the EEG, which sustained for longer than 20-30 s and associated with behavioral convulsions, appeared or not. In the following kindling session, the threshold intensity required to produce afterdischarges (ADs) in the HS rats (187 +/- 16 microA) was significantly lower than in the rats without HS (293 +/- 41 microA). However, there was no clear difference between the development of the kindling phenomenon to repeated tetanus at the threshold intensity in the rats with and without HS. It was concluded that potentiation of synaptic responses consists of two different components, transient potentiation induced by hyperthermia alone and LTP induced by HS, and that developing rats were susceptible to kindling epilepsy at the lower AD threshold intensity when experienced HS.

To study the disease process in the brain in subacute sclerosing panencephalitis (SSPE), sequential changes in ferritin, creatine kinase (CK), and neopterin in the cerebrospinal fluid (CSF) of two patients with SSPE were compared with the changes in the clinical signs and symptoms and the findings by magnetic resonance imaging (MRI). On the basis of changes in various substances in the CSF, especially ferritin, CK and neopterin, we concluded that the high-intensity area in MRI might be evidence of local inflammation and the resulting cell damage. Ferritin, CK and neopterin seemed to be biochemical markers in patients with SSPE for detection of the extent of lesions, and their measurement may provide information useful for evaluation of the therapeutic response.