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1.
Microbiology (Reading) ; 168(9)2022 09.
Article in English | MEDLINE | ID: mdl-36178719

ABSTRACT

In comparison with terrestrial mammals, dolphins require a large amount of haemoglobin in blood and myoglobin in muscle to prolong their diving time underwater and increase the depth they can dive. The genus Cetobacterium is a common gastrointestinal bacterium in dolphins and includes two species: C. somerae and C. ceti. Whilst the former produces vitamin B12, which is essential for the biosynthesis of haem, a component of haemoglobin and myoglobin, but not produced by mammals, the production ability of the latter remains unknown. The present study aimed to isolate C. ceti from dolphins and reveal its ability to biosynthesize vitamin B12. Three strains of C. ceti, identified by phylogenetic analyses with 16S rRNA gene and genome-based taxonomy assignment and biochemical features, were isolated from faecal samples collected from two captive common bottlenose dolphins (Tursiops truncatus). A microbioassay using Lactobacillus leichmannii ATCC 7830 showed that the average concentration of vitamin B12 produced by the three strains was 11 (standard deviation: 2) pg ml-1. The biosynthesis pathway of vitamin B12, in particular, adenosylcobalamin, was detected in the draft genome of the three strains using blastKOALA. This is the first study to isolate C. ceti from common bottlenose dolphins and reveal its ability of vitamin B12 biosynthesis, and our findings emphasize the importance of C. ceti in supplying haemoglobin and myoglobin to dolphins.


Subject(s)
Bottle-Nosed Dolphin , Common Dolphins , Animals , Bottle-Nosed Dolphin/genetics , Bottle-Nosed Dolphin/microbiology , Clostridiales , Common Dolphins/genetics , Fusobacteria , Gastrointestinal Contents , Heme , Myoglobin/genetics , Phylogeny , RNA, Ribosomal, 16S/genetics , Vitamin B 12 , Vitamins
2.
J Vet Med Sci ; 82(10): 1558-1561, 2020 Oct 30.
Article in English | MEDLINE | ID: mdl-32938832

ABSTRACT

We investigated the prevalence of Salmonellaenterica and its antimicrobial resistance from 79 green anoles, the invasive alien species inhabits Haha-jima of the Ogasawara archipelago. Samples were collected during the period between 2009 and 2010. The resistance of S. enterica of these samples against 12 common antimicrobial agents was also determined. Salmonella strains, including serovar Oranienburg and Aberdeen, were detected from the large intestines of 30.4% of 79 green anole samples. And 37.5% of which were resistant to Oxytetracycline. This study suggests that green anoles may play an important role of the infection of S. enterica on this island. Attention is needed from the aspect of public and ecological health.


Subject(s)
Anti-Infective Agents/pharmacology , Lizards/microbiology , Salmonella/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Birds/microbiology , Drug Resistance, Multiple, Bacterial , Introduced Species , Islands , Japan/epidemiology , Microbial Sensitivity Tests/veterinary , Prevalence , Salmonella/isolation & purification , Salmonella enterica/drug effects , Salmonella enterica/isolation & purification
3.
J Vet Med Sci ; 82(5): 678-680, 2020 May 20.
Article in English | MEDLINE | ID: mdl-32213730

ABSTRACT

Here, we investigated the prevalence of Salmonella enterica, with and without resistance to 17 common antimicrobial agents, in 706 green anoles (Anolis carolinensis) that were collected in Naha and Tomigusuku Cities, Okinawa Main Island, Japan, between 2009 and 2014. Salmonella strains, including S. enterica Weltevreden and Enteritidis serovars, were identified in the large intestinal content samples extracted from 15 (2.1%) of the analyzed green anoles. No antimicrobial resistance was detected. Thus, the present study demonstrates that although the prevalence of Salmonella and the risk of its transmission from the green anoles to humans or other animals on Okinawa Main Island are relatively low, the green anole population nevertheless represents a potential source of Salmonella infection that could affect human health in this region.


Subject(s)
Intestine, Large/microbiology , Lizards/microbiology , Salmonella/isolation & purification , Animals , Drug Resistance, Microbial , Introduced Species , Japan , Prevalence , Salmonella/classification
4.
Medicina (Kaunas) ; 55(11)2019 Nov 09.
Article in English | MEDLINE | ID: mdl-31717519

ABSTRACT

Background and Objectives: Physical function is influenced by light irradiation, and interest in the influence of light irradiation on health is high. Light signals are transmitted from the retina to the suprachiasmatic nucleus (SCN) via the retinal hypothalamic tract as non-image vision. Additionally, the SCN projects a nerve to the paraventricular nucleus (PVN) which acts as a stress center. This study examined the influences of three different light sources on neural activity in the PVN region using two different color temperatures. Materials and Methods: Experiments were conducted using twenty-eight Institute of Cancer Research (ICR) mice (10 week old males). Three light sources were used: (1) organic light-emitting diode (OLED) lighting, (2) LED lighting, and (3) fluorescent lighting. We examined the effects of light irradiation from the three light sources using two different color temperatures (2800 K and 4000 K). Perfusion was done 60 min after light irradiation, and then the brain was removed from the mouse for an immunohistochemistry analysis. c-Fos was immunohistochemically visualized as a marker of neural activity in the PVN region. Results: The number of c-Fos-positive cells was found to be significantly lower under OLED lighting and LED lighting conditions than under fluorescent lighting at a color temperature of 2800 K, and significantly lower under OLED lighting than LED lighting conditions at a color temperature of 4000 K. Conclusions: This study reveals that different light sources and color temperatures alter the neural activity of the PVN region. These results suggest that differences in the light source or color temperature may affect the stress response.


Subject(s)
Neurons/physiology , Paraventricular Hypothalamic Nucleus/physiopathology , Photic Stimulation/methods , Animals , Disease Models, Animal , Male , Mice , Paraventricular Hypothalamic Nucleus/abnormalities , Spectrophotometry/methods
5.
ACS Omega ; 4(5): 8299-8304, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31459916

ABSTRACT

Here, we show the effect of water-organic (acetone, tert-butyl alcohol, and isopropanol) cosolvents on nucleation and anisotropic crystal growth of solution-synthesized ZnO nanowires. The addition of organic solution does not alter the face-selective crystal growth nature but significantly promotes the crystal growth of both length and diameter of the nanowires. Systematic investigations reveal that a variation of the relative dielectric constant in the cosolvent can rigorously explain the observed effect of the water-organic cosolvent on the ZnO nanowire growth via the degree of supersaturation for the nucleation. The difference between acetone, tert-butyl alcohol, and isopropanol on the cosolvent effect can be interpreted in terms of a local solvent-sorting effect.

6.
Nano Lett ; 19(3): 1675-1681, 2019 03 13.
Article in English | MEDLINE | ID: mdl-30827116

ABSTRACT

In general, the electrical conductivities of n-type semiconducting metal oxide nanostructures increase with the decrease in the oxygen partial pressure during crystal growth owing to the increased number of crystal imperfections including oxygen vacancies. In this paper, we report an unusual oxygen partial pressure dependence of the electrical conductivity of single-crystalline SnO2 nanowires grown by a vapor-liquid-solid (VLS) process. The electrical conductivity of a single SnO2 nanowire, measured using the four-probe method, substantially decreases by 2 orders of magnitude when the oxygen partial pressure for the crystal growth is reduced from 10-3 to 10-4 Pa. This contradicts the conventional trend of n-type SnO2 semiconductors. Spatially resolved single-nanowire electrical transport measurements, microstructure analysis, plane-view electron energy-loss spectroscopy, and molecular dynamics simulations reveal that the observed unusual oxygen partial pressure dependence of the electrical transport is attributed to the intrinsic differences between the two crystal growth interfaces (LS and VS interfaces) in the critical nucleation of the crystal growth and impurity incorporation probability as a function of the oxygen partial pressure. The impurity incorporation probability at the LS interface is always lower than that at the VS interface, even under reduced oxygen partial pressures.

7.
Nano Lett ; 17(8): 4698-4705, 2017 08 09.
Article in English | MEDLINE | ID: mdl-28671477

ABSTRACT

Single crystalline nanowires composed of semiconducting metal oxides formed via a vapor-liquid-solid (VLS) process exhibit an electrical conductivity even without an intentional carrier doping, although these stoichiometric metal oxides are ideally insulators. Suppressing this unintentional doping effect has been a challenging issue not only for metal oxide nanowires but also for various nanostructured metal oxides toward their semiconductor applications. Here we demonstrate that a pure VLS crystal growth, which occurs only at liquid-solid (LS) interface, substantially suppresses an unintentional doping of single crystalline SnO2 nanowires. By strictly tailoring the crystal growth interface of VLS process, we found the gigantic difference of electrical conduction (up to 7 orders of magnitude) between nanowires formed only at LS interface and those formed at both LS and vapor-solid (VS) interfaces. On the basis of investigations with spatially resolved single nanowire electrical measurements, plane-view electron energy-loss spectroscopy, and molecular dynamics simulations, we reveal the gigantic suppression of unintentional carrier doping only for the crystal grown at LS interface due to the higher annealing effect at LS interface compared with that grown at VS interface. These implications will be a foundation to design the semiconducting properties of various nanostructured metal oxides.

8.
Nano Lett ; 16(12): 7495-7502, 2016 12 14.
Article in English | MEDLINE | ID: mdl-27960479

ABSTRACT

Vapor-liquid-solid (VLS) growth process of single crystalline metal oxide nanowires has proven the excellent ability to tailor the nanostructures. However, the VLS process of metal oxides in general requires relatively high growth temperatures, which essentially limits the application range. Here we propose a rational concept to reduce the growth temperature in VLS growth process of various metal oxide nanowires. Molecular dynamics (MD) simulation theoretically predicts that it is possible to reduce the growth temperature in VLS process of metal oxide nanowires by precisely controlling the vapor flux. This concept is based on the temperature dependent "material flux window" that the appropriate vapor flux for VLS process of nanowire growth decreases with decreasing the growth temperature. Experimentally, we found the applicability of this concept for reducing the growth temperature of VLS processes for various metal oxides including MgO, SnO2, and ZnO. In addition, we show the successful applications of this concept to VLS nanowire growths of metal oxides onto tin-doped indium oxide (ITO) glass and polyimide (PI) substrates, which require relatively low growth temperatures.

9.
ACS Appl Mater Interfaces ; 8(41): 27892-27899, 2016 Oct 19.
Article in English | MEDLINE | ID: mdl-27670883

ABSTRACT

Here we show a rational strategy to fabricate single crystalline NiO nanowires via a vapor-liquid-solid (VLS) route, which essentially allows us to tailor the diameter and the spatial position. Our strategy is based on the suppression of the nucleation at vapor-solid (VS) interface, which promotes nucleation only at the liquid-solid (LS) interface. Manipulating both the supplied material fluxes (oxygen and metal) and the growth temperature enables enhancement of the nucleation only at the LS interface. Furthermore, this strategy allows us to reduce the growth temperature of single crystalline NiO nanowires down to 550 °C, which is the lowest growth temperature so far reported.

10.
Rev Sci Instrum ; 86(1): 014101, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25638100

ABSTRACT

A Fourier transform two-dimensional fluorescence excitation spectrometer (FT-2DFES) was developed based on the multiplex technique using a tandem Fabry-Pérot interferometer (tandem FPI). In addition to the advantage of the multiplex technique, the main advantage of the tandem FPI is applicable to the modulation of transition with a large absorption bandwidth (larger than 100 nm) and is thus applicable to the modulation of the excitation of molecules in the condensed phase. As a demonstration of the effectiveness of FT-2DFES, we succeeded in separately observing the fluorescence excitation peaks from a mixed methanol solution of laser dyes (coumarin 480, rhodamine 6G, DCM (4-dicyanomethylene-2-methyl-6-(p-(dimethylamino)styryl)-4H-pyran), and LDS750). Furthermore, the energy transfer from rhodamine 6G to LDS750 was observed.

11.
Biocontrol Sci ; 18(3): 151-5, 2013.
Article in English | MEDLINE | ID: mdl-24077538

ABSTRACT

Solvent extracts from the carnivorous plant Dionaea muscipula (Venus flytrap) were prepared using eight different organic solvents, and examined for antibacterial activity against food-related pathogenic and putrefactive bacteria. All solvent extracts showed higher antibacterial activity against gram positive bacteria than against gram negative bacteria. The TLC-bioautography analysis of the extracts revealed that a yellow spot was detected at Rf value of 0.85, which showed strong antibacterial activity. The UV, MS, and NMR analyses revealed that the antibacterial compound was plumbagin.


Subject(s)
Anti-Bacterial Agents/pharmacology , Droseraceae/chemistry , Food Microbiology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Plant Extracts/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Chromatography, Thin Layer , Magnetic Resonance Spectroscopy , Mass Spectrometry , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Spectrophotometry, Ultraviolet
12.
Reprod Sci ; 17(7): 679-84, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20445009

ABSTRACT

OBJECTIVE: To investigate the mid-term effect of uterine artery embolization (UAE) on fertility after bilateral UAE with either tris-acryl gelatin microspheres (TAGM) or gelatin particles (GP). MATERIALS AND METHODS: Fertility was compared in 6 ewes that underwent UAE with TAGM, 6 ewes that underwent UAE with GP, and 6 control ewes. All ewes were artificially inseminated or naturally bred for 2 consecutive breeding seasons after UAE. Pregnancies in each breeding season were investigated. RESULTS: Overall, 36 lambs, all normal in appearance, were delivered after 2 breeding seasons. All 18 ewes delivered lambs in at least the first or second breeding season, with 13 having lambs in both the first and second breeding seasons. In the first breeding season after UAE, all 12 ewes in the UAE group delivered lambs, while 5 (83.3%) of the 6 ewes in the control group did. In the second breeding season, 9 (90%) of the 10 ewes that were alive in the UAE group delivered lambs, while 5 (83.3%) of 6 ewes in the control group did. There were no significant differences in the rate of ewes delivering in the first and second breeding season between control and UAE groups (P = .3333; first season, P > .9999; second season, Fisher exact probability test). CONCLUSION: The mid-term influence of UAE on reproductive ability in sheep was minimal.


Subject(s)
Models, Animal , Reproduction/physiology , Seasons , Uterine Artery Embolization , Animals , Animals, Newborn , Female , Fertility/physiology , Pregnancy , Pregnancy Outcome , Random Allocation , Sheep , Uterine Artery Embolization/methods
13.
J Vet Sci ; 11(1): 89-91, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20195071

ABSTRACT

Caudolateral curvilinear osteophyte (CCO), an osteophyte at the site of joint capsule attachment on the caudal aspect of the femoral neck, has been advocated as a radiographic criterion for coxofemoral subluxation. The correlation between the presence of CCO on radiographs (radiographic-CCO), the size of the CCO (CCO index) on three-dimensional computed tomographic (CT) images, and hip evaluation using transverse CT images was assessed in 22 Border Collies. CCOs were detected on the radiographs and CT images of 32% and 100% femurs, respectively. The CCO index correlated significantly with radiographic-CCO, but a large CCO index did not necessarily imply that the CCO was visible on radiographs. Hence, radiographic-CCO findings should be used cautiously in hip evaluation of Border Collies.


Subject(s)
Dog Diseases/physiopathology , Hip Dysplasia, Canine/physiopathology , Osteophyte/physiopathology , Animals , Dog Diseases/diagnostic imaging , Dogs , Female , Hip Dysplasia, Canine/diagnostic imaging , Image Processing, Computer-Assisted , Male , Osteophyte/diagnostic imaging , Tomography, X-Ray Computed/veterinary
14.
Reprod Sci ; 17(4): 350-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19949190

ABSTRACT

OBJECTIVE: To investigate the influence of uterine artery embolization (UAE) on fertility after bilateral UAE with either tris-acryl gelatin microspheres (TAGM) or gelatin particles (GP). MATERIALS AND METHODS: Six ewes that underwent UAE with TAGM, 6 ewes that underwent UAE with GP, and 6 control ewes were compared. After hormonal synchronization of the menstrual cycle, artificial insemination (AI) was performed. When pregnancy did not result, ewes were naturally inseminated. RESULTS: After AI, progesterone concentrations in blood increased and were maintained at >1.0 ng/mL in 9 ewes (3 per group). Three ewes became pregnant after AI. The abortion rate was higher in the UAE group. The remaining 15 sheep were naturally inseminated, with 14 delivering 15 lambs. Mean period of term gestation in UAE group ewes was 155.7 versus 158.6 days in control group ewes. Lambs' body weight, body length, and withers height after birth did not differ between those from UAE group and control group. Lambs from ewes embolized with GP tended to be smaller and had lower body weight than those from other groups. CONCLUSION: Uterine artery embolization influenced reproductive ability in sheep and UAE with GP could lead to intrauterine growth retardation.


Subject(s)
Fetal Growth Retardation/etiology , Infertility, Female/etiology , Uterine Artery Embolization/adverse effects , Acrylic Resins/administration & dosage , Animals , Disease Models, Animal , Female , Fetal Growth Retardation/blood , Gelatin/administration & dosage , Infertility, Female/blood , Pregnancy , Sheep
15.
J Vet Med Sci ; 71(2): 247-50, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19262043

ABSTRACT

The purpose of this study was to obtain the computed tomography (CT) data for the hip joints of 22 Border Collies. The dorsolateral subluxation (DLS) score, lateral center edge angle (LCEA), dorsal acetabular rim angle (DARA) and center distance (CD) index were measured on the CT images in a weight-bearing position. Radiographic Norberg angle (NA) was also measured. The mean values were 45.7 +/- 10.2% for DLS score, 85.9 degrees +/- 10.3 degrees for LCEA, 18.5 degrees +/- 7.3 degrees for DARA, 0.40 +/- 0.17 for CD index and 102.7 degrees +/- 6.9 degrees for NA. Since the DLS score and LCEA showed strong correlation, combined use of these parameters might improve diagnostic accuracy. We consider CT evaluation in a weight-bearing position to be a useful method for multidirectional evaluation of hips.


Subject(s)
Dog Diseases/diagnostic imaging , Hip Dysplasia, Canine/diagnostic imaging , Hip Joint/diagnostic imaging , Joint Instability/diagnostic imaging , Tomography, X-Ray Computed/veterinary , Acetabulum/diagnostic imaging , Animals , Dogs , Evaluation Studies as Topic , Reference Values , Sensitivity and Specificity , Weight-Bearing
16.
Appl Environ Microbiol ; 68(5): 2337-43, 2002 May.
Article in English | MEDLINE | ID: mdl-11976106

ABSTRACT

Rhodococcus rhodochrous S-2 produces extracellular polysaccharides (S-2 EPS) containing D-glucose, D-galactose, D-mannose, D-glucuronic acid, and lipids, which is important to the tolerance of this strain to an aromatic fraction of (AF) Arabian light crude oil (N. Iwabuchi, N. Sunairi, H. Anzai, M. Nakajima, and S. Harayama, Appl. Environ. Microbiol. 66:5073-5077, 2000). In the present study, we examined the effects of S-2 EPS on the growth of indigenous marine bacteria on AF. Indigenous bacteria did not grow significantly in seawater containing AF even when nitrogen, phosphorus, and iron nutrients were supplemented. The addition of S-2 EPS to seawater containing nutrients and AF resulted in the emulsification of AF, promotion of the growth of indigenous bacteria, and enhancement of the degradation of AF by the bacteria. PCR-denaturing gradient gel electrophoresis analyses show that addition of S-2 EPS to the seawater containing nutrients and AF changed the composition of the bacterial populations in the seawater and that bacteria closely related to the genus Cycloclasticus became the major population. These results suggest that Cycloclasticus was responsible for the degradation of hydrocarbons in AF. The effects of 15 synthetic surfactants on the degradation of AF by indigenous marine bacteria were also examined, but enhancement of the degradation of AF was not significant. S-2 EPS was hence the most effective of the surfactants tested in promoting the biodegradation of AF and may thus be an attractive agent to use in the bioremediation of oil-contaminated marine environments.


Subject(s)
Hydrocarbons, Aromatic/metabolism , Petroleum/analysis , Polysaccharides, Bacterial/pharmacology , Rhodococcus/chemistry , Water Microbiology , Alteromonas/metabolism , Marine Biology , Polymerase Chain Reaction , Sphingomonas/metabolism , Surface-Active Agents/pharmacology
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