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This paper devised a novel Christmas‐tree structure for flexible neural probes, which features recording sites on side‐branches that can be folded along the shank of the probe by temporary encapsulation before implantation. This design reduces the size of the implant and minimizes the surgical footprint. Upon implantation, the temporary encapsulation dissolves in vivo, leading to self‐stretching of the branches, and an expansion of the lateral detecting range of the probe. We conducted in vitro experiment with our probe in 0.6% agar that mimics the brain tissue environment. The results demonstrate that the neural probe we have developed exhibits self‐stretching ability and provides an increased lateral recording range without causing additional damage to the brain tissue. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae chrysovirus 1 (MoCV1) is a mycovirus with a dsRNA genome that infects the rice blast fungus Magnaporthe oryzae and impairs its growth. To date, MoCV1 has only been found in Vietnamese isolates of M. oryzae, and the distribution of this virus in M. oryzae isolates from other parts of the world remains unknown. In this study, using a one-step reverse transcription PCR (RT-PCR) assay, we detected a MoCV1-related virus in M. oryzae in Japan (named MoCV1-AK) whose sequence shares considerable similarity with that of the MoCV1 Vietnamese isolate. To establish a system for a comprehensive survey of MoCV1 infection in the field, we developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for direct detection of the virus. The sensitivity of the RT-LAMP assay was at least as high as that of the one-step RT-PCR assay. In addition, we detected MoCV1-AK in M. oryzae-infected oatmeal agar plates and lesions on rice leaves using the RT-LAMP assay without dsRNA extraction, by simple sampling with a toothpick. Preliminary screening of MoCV1 in Japanese M. oryzae isolates indicated that MoCV1 is currently distributed in rice fields in Japan. Our results provide a first example of the application of RT-LAMP for the detection of mycoviruses, which will accelerate surveys for mycovirus infection. [ABSTRACT FROM AUTHOR]

Abstract: A seroepidemiological survey of bovine leukemia virus (BLV) infection was conducted in Japan in 2007 using an enzyme-linked immunosorbent assay (ELISA) and an agar gel immunodiffusion (AGID) test. A total of 5420 cattle (dairy, 3966; breeding beef, 797; fattening beef, 657) from 209 farms in seven prefectures in Japan were tested. The overall prevalence of BLV infection was 28.6%. The prevalence of BLV infection in dairy cattle (34.7%) was higher than for both fattening beef cattle (7.9%) and breeding beef cattle (16.3%). Age-specific prevalence showed that BLV prevalence increased with age in all types of cattle and was notably different between dairy and beef cattle under 1 year of age. Among 207 farms, 141 herds (68.1%) had one or more positive animals. The proportion of these positive farms was significantly higher among dairy farms (79.1%) than among beef breeding farms (39.5%) and beef fattening farms (51.9%) (P <0.001). Dairy farms (40.5%) also showed a significantly higher within-herd prevalence than beef breeding (27.4%) and fattening (14.9%) farms (P =0.001). This study indicated that BLV is more widely spread in dairy cattle than in beef breeding cattle in Japan. Given the prevalence of BLV infection in dairy and beef cattle was 8- and 1.7-fold higher, respectively, than rates previously found in 1980–1982, BLV appears to be spreading particularly among the dairy cattle population during the last two decades. Further investigation is required to determine the risk factors necessary to control BLV infection that take into account the different farming practices that exist between dairy and beef sectors. [Copyright &y& Elsevier]

Bacterial culture based on the use of plate media is an effective method for investigating bacterial populations in the environment. To improve the culturability of bacteria from freshwater lakes, we developed a new medium, FW70, which contains sodium pyruvate, casamino acids, and lake water and is solidified using gellan gum. To test the importance of these components, we prepared a series of media in which one or more of the components was absent. Water was sampled 31 times from 3 Japanese lakes and was passed through a membrane filter (pore size = 0.45 µm) to remove fast-growing microbes before the water was spread onto the plates. In most cases, significantly larger numbers of bacterial colonies were detected on FW70 than on other media. Furthermore, to test the practicality of FW70, we compared it with standard nutrient agar and R2A agar. In all cases, the culturability was significantly greater on FW70 than on standard nutrient agar or R2A agar. Some isolates recovered by means of FW70 belonged to bacteria that had not previously been classified. These results suggest that FW70 improves the culturability of freshwater bacteria and can be used for the isolation of novel bacteria as a result of the filtration step. La culture bactérienne sur plaque est une méthode efficace d’investigation des populations bactériennes dans l’environnement. Afin d’améliorer la cultivabilité des bactéries des lacs d’eau douce, nous avons développé un nouveau milieu, le FW70, qui contient du pyruvate de sodium, des acides casaminés et de l’eau de lac, solidifié par l’ajout de gomme gellane. Pour tester l’importance de ces composantes, nous avons préparé une série de milieux dans lesquels une ou plusieurs des composantes ont été retirées. Trente et un échantillons prélevés de 3 lacs japonais ont été filtrés à travers une membrane (taille des pores = 0,45 µm) pour enlever les microbes à croissance élevée avant d’être étalés sur les plaques. Dans la plupart des cas, un nombre significativement plus élevé de colonies bactériennes a été détecté sur le milieu FW70 comparativement aux autres milieux. De plus, afin de tester l’aspect pratique du FW70, nous l’avons comparé à une gélose nutritive standard et à la gélose R2A. Dans tous les cas, la cultivabilité était plus grande sur le FW70 que sur les géloses nutritives standard et la gélose R2A. Quelques isolats récupérés sur le FW70 comportaient des bactéries encore non classifiées à ce jour. Ces résultats suggèrent que le FW70 améliore la cultivabilité des bactéries d’eau douce et qu’il peut être utilisé pour isoler de nouvelles bactéries résultant d’une filtration. [ABSTRACT FROM AUTHOR]

Neodiplogaster crenatae Kanzaki, Masuya & Kubono sp. n. and N. acaloleptae Kanzaki sp. n. are described and figured. Neodiplogaster crenatae sp. n. was isolated from the bark beetles Scolytoplatypus daimio and S. shogun (Scolytidae) emerging from dead logs of Fagus crenata, and was cultured on Botrytis cinerea growing on malt extract agar. Neodiplogaster crenatae sp. n. has male spicules which are relatively stout and arcuate in lateral view but curved to appear Y-shaped in ventral view; the male tail tip is bifurcate and the female tail is long and tapered. Neodiplogaster crenatae sp. n. appears closest to N. velata but is distinguished from it by spicular morphology and female tail length. Neodiplogaster acaloleptae sp. n. was isolated from the cerambycid beetle Acalolepta luxuriosa and reared on B. cinerea growing on potato dextrose agar. Neodiplogaster acaloleptae sp. n. has a conical male tail with narrow bursa covering the entire tail, smoothly tapered and strongly arcuate male spicules, leaf-shaped gubernaculum with a pointed anterior end, and long female tail with a filiform terminus. The new species is close to N. pinicola, N. piniphili and N. wacheki, but may be distinguished by its long female tail and male gubernaculum shape. The partial SSU and D2/D3 LSU of N. crenatae sp. n. were sequenced and compared with those of other sequenced nematodes, revealing that SSU was closest to those of other diplogastrid species, but that D2/D3 LSU was close to Anisakis spp. Neodiplogaster crenatae sp. n. propagated on a fungal lawn of B. cinerea and ambrosia fungi associating with its carrier beetles, but the nematode did not propagate on bacteria. The main food resource of Neodiplogaster spp. is hypothesised to be fungi. [ABSTRACT FROM AUTHOR]

Different methods were investigated for the rapid mass culture of Cistella japonica by using water extracts of some nutritional sources. In an agar culture test, there was little difference in mycelial growth in water extracts of wheat bran, rice bran and potato. In suspension culture with wheat bran extract, which is easily and cheaply available, the mycelium of C. japonica increased seven times more than that in agar culture after a month's incubation. C. japonica from suspension culture was pathogenic to Chamaecyparis obtusa. These results suggest that suspension culture in water extract of wheat bran can be adopted for the rapid mass culturing of C. japonica for use in inoculation tests. [ABSTRACT FROM AUTHOR]

Studies the thermostability of β-Agarase from the novel marine isolate, JAMB-A94 by researchers from Japan. Success of the researchers in cloning and sequencing agaA gene from the marine bacterium JAMB-A94; Calculation of the molecular mass of the protein encoded from the agaA gene; Presence of agarose and agaropectins in the cell walls of some red algae.

A highly methylated agar was isolated from Gracilaria arcuata which was harvested from Ishigaki Island, Okinawa, Japan. The yield of the agar was 33.2% (w/w dry algae). Gelation occurred at a concentration of 0.35% (w/v) at room temperature. The total carbohydrate, sulphate, ash and methoxyl content were 85.0, 0.8, 3.8 and 13.4% (w/w), respectively. The methylated sugar was identified as 6-O-methyl-d-galactose and 2-O-methyl-anhydro-l-galactose residues, respectively, by 13C- and 1H-NMR spectroscopy. The methylated agar was composed of d-galactose, 6-O-methyl-d-galactose, 3,6-anhydro-l-galactose, and 2-O-methyl-3,6-anhydro-l-galactose. [ABSTRACT FROM AUTHOR]

Recent studies in mammals have suggested that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) - phosphatidylinositol-3, 4, 5-trisphosphate pathway in oocytes might be related to the pathogenesis of premature ovarian failure (POF). The aim of this study was to investigate whether mutations of the PTEN gene are present in women with POF. We analyzed the coding region of the PTEN gene in 20 women with idiopathic POF and 20 normal controls. The PTEN gene was amplified by the polymerase chain reaction using genomic DNA isolated from blood samples. Amplified DNA was analyzed by denaturing gradient gel electrophoresis and direct sequencing. No causative mutation was detected in the coding regions of this gene. Although we found a point variation in exon 7 of one POF patient, this was a single nucleotide polymorphism that has already been reported. [ABSTRACT FROM AUTHOR]