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1.
Int Immunol ; 34(10): 505-518, 2022 09 09.
Article in English | MEDLINE | ID: mdl-35759801

ABSTRACT

Nod-like receptor family pyrin domain-containing 3 (NLRP3) is a cytosolic innate immune receptor that senses organelle dysfunction induced by various stimuli, such as infectious, environmental, metabolic and drug stresses. Upon activation, NLRP3 forms an inflammasome with its adaptor protein apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and caspase-1, to trigger the release of inflammatory cytokines. The development of effective anti-inflammatory drugs targeting the NLRP3 inflammasome is in high demand as its aberrant activation often causes inflammatory diseases. Here, we found that nanaomycin A (NNM-A), a quinone-based antibiotic isolated from Streptomyces, effectively inhibited NLRP3 inflammasome-mediated inflammatory responses induced by imidazoquinolines, including imiquimod. Interestingly, its epoxy derivative nanaomycin E (NNM-E) showed a comparable inhibitory effect against the NLRP3 inflammasome-induced release of interleukin (IL)-1ß and IL-18 from macrophages, with a much lower toxicity than NNM-A. NNM-E inhibited ASC oligomerization and caspase-1 cleavage, both of which are hallmarks of NLRP3 inflammasome activation. NNM-E reduced mitochondrial damage and the production of reactive oxygen species, thereby preventing the activation of the NLRP3 inflammasome. NNM-E treatment markedly alleviated psoriasis-like skin inflammation induced by imiquimod. Collectively, NNM-E inhibits NLRP3 inflammasome activation by preventing mitochondrial dysfunction with little toxicity and showed an anti-inflammatory effect in vivo. Thus, NNM-E could be a potential lead compound for developing effective and safe anti-inflammatory agents for the treatment of NLRP3 inflammasome-mediated inflammatory diseases.


Subject(s)
Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Caspase 1/metabolism , Imiquimod/metabolism , Imiquimod/pharmacology , Interleukin-1beta/metabolism , Mitochondria/metabolism , Naphthoquinones
2.
Biochem Biophys Res Commun ; 524(1): 8-15, 2020 03 26.
Article in English | MEDLINE | ID: mdl-31964532

ABSTRACT

BACKGROUND AND AIMS: Dipeptidyl peptidase-4 (DPP-4) inhibitors have been reported to suppress atherosclerosis progression in atherosclerotic mouse models through unclear mechanisms. In this study, we investigated the effect of the DPP-4 inhibitor, linagliptin, on macrophage polarization in vitro and in vivo. METHODS: Mouse bone marrow macrophages (BMMs) were used in in vitro assays. High fat diet (HFD)-fed Apoe-/- mice were treated orally with linagliptin (10 mg/kg-1•day-1) or a vehicle (water) control. RESULTS: In in vitro assays using BMMs, treatment with LPS and IFNγ decreased the mRNA-expression levels of alternatively activated macrophage (M2) markers, and linagliptin treatment prevented these reductions. The mRNA levels of M2 markers and the number of M2 macrophages in the aorta were higher in linagliptin groups than in control groups. Linagliptin decreased the size of atherosclerotic lesions in HFD-fed Apoe-/- mice. Interestingly, inflammatory stimulation increased DPP-4 expression, and linagliptin suppressed these effects in BMMs. Treatment with DPP-4 small-interfering RNA (siRNA) reproduced linagliptin-mediated alteration of M2 polarization. CONCLUSIONS: Linagliptin increased M2 macrophage polarization by inhibiting DPP-4 expression and activity. These findings may indicate the beneficial effects of DPP-4 inhibitors on the progression of diabetic macrovascular complications.


Subject(s)
Anti-Inflammatory Agents/chemistry , Dipeptidyl Peptidase 4/metabolism , Dipeptidyl-Peptidase IV Inhibitors/chemistry , Inflammation/drug therapy , Linagliptin/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Aorta/metabolism , Atherosclerosis/drug therapy , Bone Marrow Cells/drug effects , Diet, High-Fat , Dipeptidyl Peptidase 4/genetics , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Gene Expression Regulation/drug effects , Humans , Linagliptin/pharmacology , Macrophages/cytology , Macrophages/drug effects , Male , Mice , Mice, Inbred C57BL , Models, Animal , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism
3.
Neuroimage ; 202: 116051, 2019 11 15.
Article in English | MEDLINE | ID: mdl-31351164

ABSTRACT

We investigated the effects of long-term training on the neural representation of individual finger movements in the primary sensorimotor cortex. One group of participants (trained group) included subjects trained in playing the piano (mean years of experience = 17.9; range = 9-26; n = 20). The other group of participants (novice group) had no prior experience (n = 20). All participants performed finger-tapping movements using either of the four digits of the hand (index, middle, ring, and little fingers). Functional magnetic resonance imaging (fMRI) was used to analyze the spatial activation patterns elicited by individual finger movements. Subsequently, we tried to classify the finger that was being moved using a multi-voxel pattern analysis (MVPA). Our results showed significantly higher-than-chance classification accuracies in both primary motor cortex (M1) and somatosensory cortex (S1) contralateral to the hand. We also found significantly lower classification accuracies for both hands in the trained group compared with the novice group in M1, without significant differences in the average signal changes and the number of activated voxels for individual fingers or overlap between digits. Representational similarity analysis (RSA) also demonstrated the differences in similarity patterns of activations between the trained and novice groups in M1. Our results indicate the modulation of neural representations of individual finger movements of M1 due to long-term training.


Subject(s)
Motor Activity/physiology , Motor Cortex/physiology , Psychomotor Performance/physiology , Adult , Brain Mapping , Female , Fingers , Humans , Magnetic Resonance Imaging , Male , Multivariate Analysis , Practice, Psychological , Sensorimotor Cortex/physiology , Young Adult
4.
Arterioscler Thromb Vasc Biol ; 38(5): 994-1006, 2018 05.
Article in English | MEDLINE | ID: mdl-29496659

ABSTRACT

OBJECTIVE: Macrophages play a central role in various stages of atherosclerotic plaque formation and progression. The local macrophages reportedly proliferate during atherosclerosis, but the pathophysiological significance of macrophage proliferation in this context remains unclear. Here, we investigated the involvement of local macrophage proliferation during atherosclerosis formation and progression using transgenic mice, in which macrophage proliferation was specifically suppressed. APPROACH AND RESULTS: Inhibition of macrophage proliferation was achieved by inducing the expression of cyclin-dependent kinase inhibitor 1B, also known as p27kip, under the regulation of a scavenger receptor promoter/enhancer. The macrophage-specific human p27kip Tg mice were subsequently crossed with apolipoprotein E-deficient mice for the atherosclerotic plaque study. Results showed that a reduced number of local macrophages resulted in marked suppression of atherosclerotic plaque formation and inflammatory response in the plaque. Moreover, fewer local macrophages in macrophage-specific human p27kip Tg mice helped stabilize the plaque, as evidenced by a reduced necrotic core area, increased collagenous extracellular matrix, and thickened fibrous cap. CONCLUSIONS: These results provide direct evidence of the involvement of local macrophage proliferation in formation and progression of atherosclerotic plaques and plaque stability. Thus, control of macrophage proliferation might represent a therapeutic target for treating atherosclerotic diseases.


Subject(s)
Aorta/pathology , Aortitis/prevention & control , Atherosclerosis/prevention & control , Cell Proliferation , Macrophage Activation , Macrophages, Peritoneal/pathology , Plaque, Atherosclerotic , Animals , Aorta/metabolism , Aortitis/genetics , Aortitis/metabolism , Aortitis/pathology , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cells, Cultured , Collagen/metabolism , Cyclin-Dependent Kinase Inhibitor p27/genetics , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Disease Models, Animal , Fibrosis , Inflammation Mediators/metabolism , Macrophages, Peritoneal/metabolism , Male , Mice, Inbred C57BL , Mice, Knockout, ApoE , Mice, Transgenic , Necrosis , Signal Transduction
5.
BMC Genomics ; 10: 438, 2009 Sep 17.
Article in English | MEDLINE | ID: mdl-19758460

ABSTRACT

BACKGROUND: Oceans cover more than 70% of the earth's surface and are critical for the homeostasis of the environment. Among the components of the ocean ecosystem, zooplankton play vital roles in energy and matter transfer through the system. Despite their importance, understanding of zooplankton biodiversity is limited because of their fragile nature, small body size, and the large number of species from various taxonomic phyla. Here we present the results of single-gene zooplankton community analysis using a method that determines a large number of mitochondrial COI gene sequences from a bulk zooplankton sample. This approach will enable us to estimate the species richness of almost the entire zooplankton community. RESULTS: A sample was collected from a depth of 721 m to the surface in the western equatorial Pacific off Pohnpei Island, Micronesia, with a plankton net equipped with a 2-m2 mouth opening. A total of 1,336 mitochondrial COI gene sequences were determined from the cDNA library made from the sample. From the determined sequences, the occurrence of 189 species of zooplankton was estimated. BLASTN search results showed high degrees of similarity (>98%) between the query and database for 10 species, including holozooplankton and merozooplankton. CONCLUSION: In conjunction with the Census of Marine Zooplankton and Barcode of Life projects, single-gene zooplankton community analysis will be a powerful tool for estimating the species richness of zooplankton communities.


Subject(s)
Biodiversity , Genes, Mitochondrial , Zooplankton/genetics , Animals , DNA, Mitochondrial/genetics , Electron Transport Complex IV/genetics , Gene Library , Micronesia , Pacific Ocean , Phylogeny , RNA, Messenger/genetics , Sequence Analysis, DNA , Zooplankton/classification
6.
Front Hum Neurosci ; 13: 380, 2019.
Article in English | MEDLINE | ID: mdl-31708762

ABSTRACT

While common semantic representations for individual words across languages have been identified, a common meaning system at sentence-level has not been determined. In this study, fMRI was used to investigate whether an across-language sentence comprehension system exists. Chinese-Japanese bilingual participants (n = 32) were asked to determine whether two consecutive stimuli were related (coherent) or not (incoherent) to the same event. Stimuli were displayed with three different modalities (Chinese written sentences, Japanese written sentences, and pictures). The behavioral results showed no significant difference in accuracy and response times among the three modalities. Multi-voxel pattern analysis (MVPA) of fMRI data was used to classify the semantic relationship (coherent or incoherent) across the stimulus modalities. The classifier was first trained to determine coherency within Chinese sentences and then tested with Japanese sentences, and vice versa. A whole-brain searchlight analysis revealed significant above-chance classification accuracy across Chinese and Japanese sentences in the supramarginal gyrus (BA 40), extending into the angular gyrus (BA 39) as well as the opercular (BA 44) and triangular (BA 45) parts of the inferior frontal gyrus in the left hemisphere (cluster-level FWE corrected p < 0.05). Significant above-chance classification accuracy was also found across Japanese sentences and pictures in the supramarginal (BA 40) and angular gyrus (BA 39). These results indicate that a common meaning system for sentence processing across languages and modalities exists, and it involves the left inferior parietal gyrus.

7.
Atherosclerosis ; 286: 30-39, 2019 07.
Article in English | MEDLINE | ID: mdl-31096071

ABSTRACT

BACKGROUND AND AIMS: Local macrophage proliferation is linked to enhanced atherosclerosis progression. Our previous study found that troglitazone, a thiazolidinedione (TZD), suppressed oxidized low-density lipoprotein (Ox-LDL)-induced macrophage proliferation. However, its effects and mechanisms are unclear. Therefore, we investigated the effects of pioglitazone, another TZD, on macrophage proliferation. METHODS: Normal chow (NC)- or high-fat diet (HFD)-fed apolipoprotein E-deficient (Apoe-/-) mice were treated orally with pioglitazone (10 mg/kg/day) or vehicle (water) as a control. Mouse peritoneal macrophages were used in in vitro assays. RESULTS: Atherosclerosis progression was suppressed in aortic sinuses of pioglitazone-treated Apoe-/- mice, which showed fewer proliferating macrophages in plaques. Pioglitazone suppressed Ox-LDL-induced macrophage proliferation in a dose-dependent manner. However, treatment with peroxisome proliferator-activated receptor-γ (PPARγ) siRNA ameliorated pioglitazone-induced suppression of macrophage proliferation. Low concentrations (less than 100 µmol/L) of pioglitazone, which can suppress macrophage proliferation, activated PPARγ in macrophages, but did not induce macrophage apoptosis. Pioglitazone treatment did not induce TUNEL-positive cells in atherosclerotic plaques of aortic sinuses in Apoe-/- mice. CONCLUSIONS: Pioglitazone suppressed macrophage proliferation through PPARγ without inducing macrophage apoptosis. These findings imply that pioglitazone could prevent macrovascular complications in diabetic individuals.


Subject(s)
Cell Proliferation/drug effects , Macrophages/cytology , Macrophages/drug effects , PPAR gamma/physiology , Pioglitazone/pharmacology , Animals , Apolipoproteins E/deficiency , Atherosclerosis/prevention & control , Male , Mice , Mice, Inbred C57BL , Pioglitazone/therapeutic use
8.
Zool Stud ; 57: e16, 2018.
Article in English | MEDLINE | ID: mdl-31966256

ABSTRACT

Sanu Vengasseril Francis, Shuhei Nishida, and Sivasankaran Bijoy Nandan (2018) The neustonic copepods of the family Pontellidae - Pontella spinipes Giesbrecht, 1889 and P. diagonalis Wilson, 1950, both first described on the basis of female specimens exhibit very similar morphology and overlapping geographic ranges in the Indian Ocean. While several taxonomists have described males of each species, there has been no definitive evidence for female-male matching (link female and male of the same species) in the two species. In the present study, an analysis of mitochondrial cytochrome c oxidase subunit I (mtCOI) sequences in the specimens collected from the Arabian Sea revealed that female P. spinipes Giesbrecht, 1889, and male P. diagonalis sensu Silas and Pillai (1973) are genetically identical, providing evidence that the latter is actually P. spinipes. These findings emphasize that it is necessary to re-examine the female-male correspondence of other related species, formerly based on morphology alone, using molecular-genetic analysis as applied in the present study.

9.
Sci Rep ; 8(1): 16406, 2018 Nov 06.
Article in English | MEDLINE | ID: mdl-30401895

ABSTRACT

An unusual combination of a laboratory experiment and in situ measurement of pressure fluctuations during an earthquake allows us to resolve some uncertainties in bottom pressure recorders (BPRs). In situ BPRs are usually contaminated by seismic waves during earthquakes; thus uncertainty still remains in the data obtained from BPRs. We examine in situ BPR data together with pressure variations produced by a dead weight (a pressure standard) in a laboratory experiment during an earthquake. The features recorded by the in situ BPRs are analysed as part of the overall experiment. We demonstrated that a 10-kg dead weight on a piston-cylinder across an area of 10 mm2 is capable of reproducing pressure fluctuations at a depth of 1000 m in the water column. The experiment also indicates that the internal mechanics of BPRs are isolated from incident seismic waves, suggesting that BPRs measure true in situ pressures without instrumentally induced disturbances. This constitutes the first instance in which pressure fluctuations recorded by in situ BPRs during an earthquake were reproduced using a pressure standard in the laboratory.

10.
Article in English | MEDLINE | ID: mdl-27087549

ABSTRACT

Lipids of Neocalanus cristatus and Eucalanus bungii (C3 to adults), collected in March, May, and December from various depths (0-2000m) were studied in the Oyashio region, western North Pacific. Total lipid and wax ester contents of younger N. cristatus stages increased during the development, being higher in May than in March and December. Major fatty acids of younger N. cristatus were 16:0, 20:5(n-3), and 22:6(n-3) and the dominant alcohols were 16:0, 16:1(n-7), 20:1(n-9)/(n-11) and 22:1(n-11). The energy-rich 20:1 and 22:1 moieties increased from the younger to the adult stages showing the importance of lipid biosynthesis which may be advantageous for successful overwintering and reproduction at depth. The 16:4(n-1) fatty acid, characteristic of a diatom diet increased in May, particularly in the younger stages. Our results suggest that the diatom-dominated feeding mode of younger N. cristatus during the spring bloom is important for an effective accumulation of wax esters. In contrast to N. cristatus, E. bungii accumulated substantial amounts of triacylglycerols. The total lipid and triacylglycerol content increased slightly toward the older developmental stages. The major fatty acids were 16:0, 16:1(n-7), 18:1(n-9) and (n-7), and 20:5(n-3). There was no evidence of developmental or seasonal changes in the fatty acid composition. The differences in the lipid storage modes of both copepods via wax esters or triacylglycerols are species-specific but their fatty acid compositions varied according to diet and developmental stage, especially in N. cristatus. These lipid characteristics are discussed in relation to reproduction, feeding modes, diapause and overwintering strategies.


Subject(s)
Alcohols/chemistry , Copepoda/chemistry , Fatty Acids/chemistry , Lipids/chemistry , Pacific Ocean , Alcohols/metabolism , Animals , Copepoda/metabolism , Energy Metabolism , Fatty Acids/metabolism , Lipid Metabolism , Seasons
11.
Article in English | MEDLINE | ID: mdl-27933174

ABSTRACT

Hepatitis C-associated osteosclerosis (HCAO), a very rare disorder in which an extremely rapid bone turnover occurs and results in osteosclerosis, was acknowledged in 1990s as a new clinical entity with the unique bone disorder and definite link to chronic type C hepatitis, although the pathogenesis still remains unknown. Affected patients suffer from excruciating deep bone pains. We report the 19th case of HCAO with diagnosis confirmed by bone biopsy, and treated initially with a bisphosphonate, next with corticosteroids and finally with direct acting antivirals (DAA: sofosbuvir and ribavirin) for HCV infection. Risedronate, 17.5 mg/day for 38 days, did not improve the patient's symptoms or extremely elevated levels of bone markers, which indicated hyper-bone-formation and coexisting hyper-bone-resorption in the patient. Next, intravenous methylprednisolone pulse therapy followed by high-dose oral administration of prednisolone evidently improved them. DAA therapy initiated after steroid therapy successfully achieved sustained virological response, but no additional therapeutic effect on them was observed. Our results strongly suggested that the underlying immunological alteration is the crucial key to clarify the pathogenesis of HCAO. Bone mineral density of lumbar vertebrae of the patient was increased by 14% in four-month period of observation. Clarification of the mechanisms that develop osteosclerosis in HCAO might lead to a new therapeutic perspective for osteoporosis. LEARNING POINTS: HCAO is an extremely rare bone disorder, which occurs exclusively in patients affected with HCV, of which only 18 cases have been reported since 1992 and pathogenesis still remains unclear.Pathophysiology of HCAO is highly accelerated rates of both bone formation and bone resorption, with higher rate of formation than that of resorption, which occur in general skeletal leading to the diffuse osteosclerosis with severe bone pains.Steroid therapy including intravenous pulse administration in our patient evidently ameliorated his bone pains and reduced elevated values of bone markers. This was the first successful treatment for HCAO among cases reported so far and seemed to propose a key to solve the question for its pathogenesis.The speed of increase in the bone mineral content of the patient was very high, suggesting that clarification of the mechanism(s) might lead to the development of a novel therapy for osteoporosis.

12.
Curr Protein Pept Sci ; 4(3): 181-93, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12769717

ABSTRACT

The atomic force microscope has been extensively used not only to image nanometer-sized biological samples but also to measure their mechanical properties by using the force curve mode of the instrument. When the analysis based on the Hertz model of indentation is applied to the approach part of the force curve, one obtains information on the stiffness of the sample in terms of Young's modulus. Mapping of local stiffness over a single living cell is possible by this method. The retraction part of the force curve provides information on the adhesive interaction between the sample and the AFM tip. It is possible to functionalize the AFM tip with specific ligands so that one can target the adhesive interaction to specific pairs of ligands and receptors. The presence of specific receptors on the living cell surface has been mapped by this method. The force to break the co-operative 3D structure of globular proteins or to separate a double stranded DNA into single strands has been measured. Extension of the method for harvesting functional molecules from the cytosol or the cell surface for biochemical analysis has been reported. There is a need for the development of biochemical nano-analysis based on AFM technology.


Subject(s)
Biochemistry , Microscopy, Atomic Force , Nanotechnology/methods , Animals , Antigen-Antibody Reactions , Biochemical Phenomena , Biomechanical Phenomena , Cell Adhesion , Cell Membrane/chemistry , DNA/chemistry , Elasticity , Humans , Ligands , Microscopy, Atomic Force/methods , Nucleic Acid Conformation , Receptors, Cell Surface/analysis
13.
Gene ; 332: 71-8, 2004 May 12.
Article in English | MEDLINE | ID: mdl-15145056

ABSTRACT

Partial sequences of the mitochondrial genomes were determined for two calanoid copepods, Eucalanus bungii [9530 bp (base pairs)] and Neocalanus cristatus (7965 bp), using an approach that employs a long polymerase chain reaction (PCR) technique and primer walking. In contrast to Tigriopus japonicus (Harpacticoida), in which the complete mitochondrial genome has been determined, genes are encoded on both strands of the genome. In spite of the close relationship between E. bungii and N. cristatus, the gene orders of these calanoid copepods differed greatly from each other. From the sequence we obtained, new copepod-specific versatile primers were designed for the cytochrome c oxidase I (COI) gene (1200 bp). These primer pairs, as well as the previously designed primer pairs for the small ribosomal RNA (srRNA) gene (500 bp), were applied for 20 species representing four orders of both calanoid and non-calanoid copepods and amplification of sequences from at least one species from each order was successful.


Subject(s)
Copepoda/genetics , DNA, Mitochondrial/genetics , Gene Rearrangement , Animals , Base Composition , Base Sequence , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/isolation & purification , Gene Order , Mitochondrial Proteins/genetics , Molecular Sequence Data , Polymerase Chain Reaction/methods , RNA, Ribosomal/genetics , RNA, Transfer/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
14.
Ultramicroscopy ; 91(1-4): 269-74, 2002 May.
Article in English | MEDLINE | ID: mdl-12211478

ABSTRACT

A new instrument was constructed by combining an objective-type total internal reflection fluorescence microscope with an atomic force microscope (AFM). Our purpose of constructing such an instrument is to detect and confirm the result of cellular level manipulations made with the AFM part through the detection system of the highly sensitive fluorescence microscope part. In this combination, manipulations are now possible from the nanometer to the micrometer scales and the fluorescence detection system is sensitive enough even for localizing single molecules. In this paper, we applied the system as a precise intracellular injector (nanoplanter). Fluorescent beads were first chemically immobilized onto a ZnO whisker that was glued to an AFM tip and were injected into a living BALB/3T3 cell together with the whisker. It was demonstrated that the system could clearly show the result of injection, that is, the presence of a small number of fluorescent beads in the cell.


Subject(s)
3T3 Cells/ultrastructure , Microscopy, Atomic Force/methods , Microscopy, Fluorescence/instrumentation , Nanotechnology/methods , Animals , Cell Line , Mice , Mice, Inbred BALB C , Microscopy, Atomic Force/instrumentation , Microscopy, Fluorescence/methods
15.
Mar Biotechnol (NY) ; 4(4): 406-17, 2002 Sep.
Article in English | MEDLINE | ID: mdl-14961252

ABSTRACT

The complete nucleotide sequence of the mitochondrial genome was determined for a harpacticoid copepod, Tigriopus japonicus (Crustacea), using an approach that employs a long polymerase chain reaction technique and primer walking. Although the genome (14,628 bp) contained the same set of 37 genes (2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) as found in other metazoan animals, none of the previously reported gene orders were comparable to that of T. japonicus. Furthermore, all genes were encoded on one strand, unlike the mitochondrial genomes of most metazoan animals. Size reductions were notable for tRNA and rRNA genes, resulting in one of the smallest mitochondrial genomes in the arthropod lineage. Although it appears that such large-scale gene rearrangements have occurred in the ancestral species of T. japonicus, none of the proposed mechanisms parsimoniously account for this eccentric gene arrangement.

16.
Mar Biotechnol (NY) ; 6(3): 238-50, 2004.
Article in English | MEDLINE | ID: mdl-15136912

ABSTRACT

We determined the nearly complete DNA sequence of the mitochondrial genome of Antarctic krill Euphausia superba (Crustacea: Malacostraca), one of the most ecologically and commercially important zooplankters in Antarctic waters. All of the genome sequences were purified by gene amplification using long polymerase chain reaction (PCR), and the products were subsequently used as templates for either direct sequencing using a primer-walking strategy or nested PCR with crustacea-versatile primers. Although we were unable to determine a portion of the genome owing to technical difficulties, the sequenced position, 14,606 bp long, contained all of the 13 protein-coding genes, 19 of the 22 transfer RNA genes, and the large subunit as well as a portion of the small subunit ribosomal RNA genes. Gene rearrangement was observed for 3 transfer RNA genes (tRNACys, tRNATyr, and tRNATrp) and the 2 leucine tRNA genes.


Subject(s)
DNA, Mitochondrial/genetics , Euphausiacea/genetics , Gene Order , Gene Rearrangement/genetics , Amino Acid Sequence , Animals , Antarctic Regions , Base Composition , Base Pairing , Base Sequence , Cluster Analysis , DNA Primers , Molecular Sequence Data , RNA, Transfer/genetics , Sequence Analysis, DNA
17.
Anal Sci ; 18(1): 35-9, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11817724

ABSTRACT

The imprinted polymers based on a transient complex formation between methacrylic acid and template molecules were prepared by using methacrylic acid and ethylene dimethacrylate as a cross-linking agent. The template molecules used were (R,R)-cyclohexanediamine (1), (S,S)-1,2-diphenylethylenediamine (2) and (S)-1,1'-binaphthyl-2,2'-diamine (3). Another group of templates were those in which the amino group of these templates had been substituted by the hydroxy group: (R,R)-1,2-cyclohexanediol (4) and (S,S)-hydrobenzoin (5). Racemic 2 was separated by the polymer prepared with template 2 (P2) and that with template 1 (P1). Template 2 is larger than template 1 in steric bulkiness, but P1 was effective for the enantiomer separation of racemic 2. P1 was not effective for the separation of racemic 4. Enantioselectivity observed in racemic 2 in P2 was higher than that in racemic 1 in P1. P2 has no definite predetermined shape for solute 1, but it was capable of separating racemic 1. This separation should be thus ascribed to the orientation of at least two carbonyl groups reflecting the conformation of template 2 in P2 cavity. Racemic 5, having the same configuration of the two bulky phenyl groups as that of solute 2, was separated in P2. When the primary amines such as propylamine, cyclohexylamine and 1-adamantanamine were added into the acetic acid-methanol mixtures as eluents, both enantioselectivity and retentivity for racemic 2 were enhanced along with the remarkable peak tailing.


Subject(s)
Amines/chemistry , Diamines/chemistry , Cross-Linking Reagents , Stereoisomerism , Structure-Activity Relationship
18.
Zookeys ; (338): 39-54, 2013.
Article in English | MEDLINE | ID: mdl-24146583

ABSTRACT

A new species of the calanoid copepod genus Pseudodiaptomus was collected from the Prasae River Estuary, Rayong Province, on the eastern coast of the Gulf of Thailand. This species is definitely assigned to the lobus species group sensu Walter (1986a). The female of the new species differs from other congeners in the elongate genital double-somite with a blunt process ventrally and the second urosomite about 2.54 times as long as wide. The male is also easily distinguished from other congeners by the structure of the right fifth leg. The present new species is a euryhaline species and occurred in brackish waters with salinity ranging from 0.7 to 23.3. Its breeding season may be from June to October, as indicated by the presence of egg-sacs.

19.
Lab Chip ; 12(20): 4115-9, 2012 Oct 21.
Article in English | MEDLINE | ID: mdl-22847153

ABSTRACT

Here we describe the application of a recently developed high-resolution microcantilever biosensor resonating at the air-liquid interface for the continuous detection of antigen-antibody and enzyme-substrate interactions. The cantilever at the air-liquid interface demonstrated 50% higher quality factor and a 5.7-fold increase in signal-to-noise-ratio (SNR) compared with one immersed in the purified water. First, a label-free detection of a low molecular weight protein (insulin, 5.8 kDa) in physiological concentration was demonstrated. The liquid facing side of the cantilever was functionalized by coating its surface with insulin antibodies, while the opposite side was exposed to air. The meniscus membrane at the micro-slit around the cantilever sustained the liquid in the microchannel. After optimizing the process of surface functionalization, the resonance frequency shift was successfully measured for insulin solutions of 0.4, 2.0, and 6.3 ng ml(-1). To demonstrate additional application of the device for monitoring enzymatic protein degradation, the liquid facing microcantilever surface was coated with human recombinant SOD1 (superoxide dismutase 1) and exposed to various concentrations of proteinase K solution, and the kinetics of the SOD1 digestion was continuously monitored. The results showed that it is a suitable tool for sensitive protein detection and analysis.


Subject(s)
Antibodies/chemistry , Biosensing Techniques/methods , Insulin/analysis , Microfluidic Analytical Techniques/methods , Superoxide Dismutase/chemistry , Biosensing Techniques/instrumentation , Humans , Immunoenzyme Techniques , Insulin/chemistry , Insulin/metabolism , Microfluidic Analytical Techniques/instrumentation , Sensitivity and Specificity , Superoxide Dismutase-1
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