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1.
Plant Physiol ; 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34730809

RESUMO

Highly efficient tissue repair is pivotal for surviving damage-associated stress. Plants generate callus upon injury to heal wound sites, yet regulatory mechanisms of tissue repair remain elusive. Here, we identified WUSCHEL RELATED HOMEOBOX 13 (WOX13) as a key regulator of callus formation and organ adhesion in Arabidopsis (Arabidopsis thaliana). WOX13 belongs to an ancient subclade of the WOX family, and a previous study shows that WOX13 orthologues in the moss Physcomitrium patens (PpWOX13L) are involved in cellular reprogramming at wound sites. We found that the Arabidopsis wox13 mutant is totally defective in establishing organ reconnection upon grafting, suggesting that WOX13 is crucial for tissue repair in seed plants. WOX13 expression rapidly induced upon wounding, which was partly dependent on the activity of an AP2/ERF transcription factor, WOUND INDUCED DEDIFFERENTIATION 1 (WIND1). WOX13 in turn directly upregulated WIND2 and WIND3 to further promote cellular reprogramming and organ regeneration. We also found that WOX13 orchestrates the transcriptional induction of cell wall-modifying enzyme genes, such as GLYCOSYL HYDROLASE 9Bs, PECTATE LYASE LIKEs and EXPANSINs. Furthermore, the chemical composition of cell wall monosaccharides was markedly different in the wox13 mutant. These data together suggest that WOX13 modifies cell wall properties, which may facilitate efficient callus formation and organ reconnection. Furthermore, we found that PpWOX13L complements the Arabidopsis wox13 mutant, suggesting that the molecular function of WOX13 is partly conserved between mosses and seed plants. This study provides key insights into the conservation and functional diversification of the WOX gene family during land plant evolution.

2.
Zoolog Sci ; 38(3): 287-296, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34057354

RESUMO

We describe the cypridoidean ostracod Heterocypris spadix sp. nov. from brackish water on Okinawa Island, Japan. The species closely resembles Heterocypris salina (Brady, 1868) but differs in that (1) the marginal infolds on valves are less developed, (2) the tubercles on the anterior margin of the right valve are completely covered by the selvage and invisible in inner view, and (3) the calcified inner lamella on the ventral margin of the left and right valves is scarcely evident in inner view, as the ventral margins of the valves bend inwardly. We determined partial sequences for the cytochrome c oxidase subunit I (COI; cox1) and 18S rRNA genes in H. spadix for future DNA barcoding and phylogenetic analyses. Our sample contained only females. A breeding experiment revealed that H. spadix females reproduce parthenogenetically. Another experiment showed that H. spadix has low tolerance to desiccation, with all individuals at 25°C dying between 1-2 hours after removal from water. We amplified and sequenced a partial 16S rRNA sequence for the endosymbiotic bacterium Cardinium from H. spadix. Infection by Cardinium may be related to the parthenogenetic reproductive mode we observed in H. spadix.


Assuntos
Crustáceos/genética , Animais , Crustáceos/classificação , Crustáceos/fisiologia , Crustáceos/ultraestrutura , Feminino , Japão , Masculino , Reprodução , Especificidade da Espécie
3.
Zoolog Sci ; 37(5): 496-503, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32972090

RESUMO

We describe Obesostoma crinophilum sp. nov. (Ostracoda: Podocopida: Paradoxostomatidae) obtained from the body surface of the feather star Antedon serrata A. H. Clark, 1908 (Crinoidea: Comatulida: Antedonidae). This is the first report of Ostracoda associated with Crinoidea. None of the highly specialized appendages and/or carapace that are related to a commensal lifestyle were observed in O. crinophilum sp. nov. Therefore, the relationship between O. crinophilum sp. nov. and A. serrata must be transient rather than obligatory. However, O. crinophilum sp. nov. has a more developed hook-like distal claw on the antenna in comparison with four previously known Obesostoma species. The relatively well-developed distal claw of the antenna in O. crinophilum sp. nov. should indicate its intimate association with feather stars, though the feeding habit is still unknown.


Assuntos
Crustáceos/classificação , Equinodermos/fisiologia , Simbiose , Animais , Crustáceos/anatomia & histologia , Feminino , Masculino , Especificidade da Espécie
4.
Zool Stud ; 59: e13, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760459

RESUMO

The present study describes Pontopolycope orientalis sp. nov. (Polycopidae), which was collected from the shallow sandy bottom off of Nagannu Island, Okinawa Prefecture, southwestern Japan. This new species is the first living representative of Pontopolycope from the Indo-Pacific region. We also provided a key to identifying five living congeners throughout the world's oceans. Since Pontopolycope is defined by the morphological characteristics of the carapace, the following five fossil and subfossil (empty valve) species of Polycope (Polycopidae) are moved to Pontopolycope: Pontopolycope luxuriosa (Herrig, 1964) comb. nov., P. sanctacatherinae (Whatley and Downing, 1983) comb. nov., P. krauseae (Herrig, 1994) comb. nov., P. proboscidea (Herrig, 1994) comb. nov., and P. isolata (Whatley, Jones and Wouters, 2000) comb. nov. Finally, the nucleotide sequence data of three genes (18S rRNA, 28S rRNA, and mitochondrial cytochrome c oxidase subunit 1) of the new species are provided for future systematic and phylogenetic studies.

6.
Zoolog Sci ; 37(3): 240-254, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549538

RESUMO

Ostracod genus Heterodesmus Brady, 1866 is known thus far to contain only three species: H. adamsii Brady, 1866; H. apriculus Hiruta, 1992; and H. naviformis (Poulsen, 1962). This genus has been recorded from the Sea of Japan, and the coastal areas of Thailand and Vietnam. The main generic character is the presence of antero-dorsal and postero-dorsal tube-like processes on the rostrum on both valves. The three species mostly differ in the shell lateral projections. Their relationship and the position of Heterodesmus within family Cypridinidae are poorly understood, partly due to the lack of publication of DNA data so far. We study Heterodesmus collected from several localities in the Northwest Pacific, namely Tsushima and Iki Islands in Japan and Maemul Island in Korea. Besides morphological characters, we also use two mitochondrial markers (16S rRNA and mtCOI) and three nuclear regions (18S rRNA, 28S rRNA, and internal transcribed spacer - ITS) in the samples to detect the biodiversity of this genus. Our phylogenetic tree based on molecular data coupled with morphology reveals the presence of two species, H. adamsii and H. apriculus. We report on their morphological variability, molecular diversity, and phylogenetic position within Cypridinidae based on 16S, 28S and 18S rRNAs, and provide a taxonomic key for all living genera of this family. For the first time, we give an overview of the intrageneric and intrafamily DNA distances of the above markers for the entire subclass Myodocopa.


Assuntos
Crustáceos/anatomia & histologia , Crustáceos/genética , Filogenia , Animais , Proteínas de Artrópodes/análise , Biodiversidade , Crustáceos/classificação , Crustáceos/enzimologia , DNA Espaçador Ribossômico/análise , República Democrática Popular da Coreia , Complexo IV da Cadeia de Transporte de Elétrons/análise , Feminino , Japão , Masculino , Proteínas Mitocondriais/análise , RNA Ribossômico 16S/análise , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análise
7.
J Occup Health ; 62(1): e12123, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32515901

RESUMO

OBJECTIVES: Limited information exists concerning occupational risks in decontamination work after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Workers involved tend to be migrant workers, face various health risks, and are usually from a low socioeconomic background and generally have difficulty in finding employment. We report a specific case to illustrate the way these workers tend to get injured during working hours and draw attention to the problems arising. CASE PRESENTATION: A 59-year-old Japanese male decontamination worker was referred to our emergency department after a fall while he was working in an Exclusion Zone surrounding the FDNPP. He was blind in his right eye. He was diagnosed with traumatic multiple rib fractures and a tube thoracostomy was performed. He was discharged from hospital after 7 days. Payment has been changed from "occupational accident," which is required to be reported to the Local Labor Standards Office, to "general medical treatment" which is no obligation. CONCLUSION: Trauma or physical injury of any kind is an occupational hazard for workers, especially those operating in the chaotic and unpredictable environments following any disasters. Companies employing such workers and owners of any facilities or locations in which they may be working are responsible for the safety of their workers. They should provide appropriate training and should comply with all prevailing Employment Laws and follow mandatory safety regulations. If companies and authorities are in breach of any laws, ignore their responsibilities, or jeopardize the health of their workers, they should be held accountable.


Assuntos
Acidentes de Trabalho , Descontaminação , Acidente Nuclear de Fukushima , Hemopneumotórax/terapia , Fraturas das Costelas/terapia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Toracostomia
8.
Angew Chem Int Ed Engl ; 59(31): 13086-13092, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32333470

RESUMO

The development of methods to pattern nanocrystals with different sizes and shapes remains a challenge. In this study, we demonstrate a unique class of bottom-up approaches to assemble nanocrystals into patterns. Our approach for patterning nanocrystals focuses on the utilization and control of the chemical reaction of solvents surrounding nanocrystals. The photopolymerization of solvent molecules through a photomask creates time-dependent concentration gradients of the solvents. Dispersed nanocrystals such as silver nanowires (AgNWs) migrate and are gradually organized and integrated into the polymerizing films based on the concentration gradients. The AgNW-embedded film properties are determined by the organized AgNW structures and include light transmission and electrical conductivity. Overall, the demonstrated method is very simple, widely applicable to various nanocrystals and solvents, and can thus contribute to the development of a new class of nanocrystal patterning methods.

9.
J Glob Antimicrob Resist ; 20: 253-259, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31472282

RESUMO

OBJECTIVES: To characterise the genotypic profiles of methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates from companion animals and to investigate their association with those from humans in Japan. METHODS: Non-duplicated MRSA clinical isolates recovered between July 2016 and January 2018 were analysed. The MRSA isolates were typed by polymerase chain reaction (PCR)-based open reading frame (ORF) typing (POT) scores, SCCmec types, multilocus sequence typing, and virulence gene profiles. Phylogenetic comparison of those isolates with previously described human isolates was performed. RESULTS: Among 56 MRSA isolates (33 cats, 20 dogs and three rabbits), 26 isolates with a POT1 score of 93, SCCmec type II mostly belonged to CC5, including ST5. Twenty-six isolates with a POT1 score of 106, SCCmec type IV showed diversity of STs: 15 isolates belonged to CC8, mainly including ST8, and 11 isolates belonged to CC1, including ST1 and newly identified STs 4768, 4775, and 4779. Two cat isolates were ST8-SCCmec type IV possessing pvl/ACME-arcA, presumed to be the hypervirulent community-associated MRSA (CA-MRSA) clone USA300. Notably, all three rabbit isolates belonged to ST4768. The POT1 score 106 CA-MRSA isolates from animals and humans were divided into two large clusters of CC1 and CC8, where host species-specific sub-clusters were not identified within each cluster. A large cluster of POT1 score 93 healthcare-associated MRSA (HA-MRSA) isolates from animals and humans consisted of sub-clusters formed exclusively by the vast majority of human isolates and those formed by animal and human isolates. CONCLUSION: Companion animals could be potential reservoirs and vehicles for the transmission of CA-MRSA to humans, and could transmit companion animal-adaptive HA-MRSA lineages to humans as their second reservoirs.


Assuntos
Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Animais de Estimação/microbiologia , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Animais , Gatos , Cães , Genótipo , Especificidade de Hospedeiro , Humanos , Japão , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Tipagem Molecular , Filogenia , Coelhos , Infecções Estafilocócicas/veterinária , Urina/microbiologia
10.
J Glob Antimicrob Resist ; 21: 353-356, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31783194

RESUMO

OBJECTIVES: NDM-1 is by far one of the most commonly prevalent carbapenemases in Enterobacteriaceae and Acinetobacter baumannii. This study presented an Acinetobacter pittii (A. pittii) isolate co-harboring blaNDM-1 and blaOXA-820 from a university hospital sink, where New Delhi metallo-ß-lactamase (NDM) producers have not been found in either patients or their environments. METHODS: Whole-genome sequencing was performed on the HiSeq 4000 platform, and the reads were de novo assembled using the A5-miSeq Assembly pipeline. Annotation of the resulting scaffolds were performed by using the DDBJ Fast Annotation and Submission Tool (DFAST). The blaNDM-1-carrying plasmid was determined. RESULTS: The A. pittii ST220 strain SU1805 detected from a sink strainer in the treatment room was resistant to imipenem and meropenem. Antimicrobial resistance genes blaNDM-1, blaOXA-820, blaADC-43, and aphA6 were found in this strain. The blaNDM-1 was found to be located downstream of an ISAba125 element on a plasmid pSU1805NDM with a size of 41,022 bp, and GC content of 38.3% harbouring 48 protein-coding genes. The aphA6 gene was also located upstream of the ISAba125 on the same plasmid. The A. pittii intrinsic blaOXA-213-like gene blaOXA-820 was located between fxsA and yncA genes in the chromosome. The strain also harboured biofilm-associated genes such as ompA, the csu operon and their regulating genes bfmRS. CONCLUSION: This study described the first isolation of NDM-1-producing A. pittii in Japan, and highlighted the importance of proper implementation of measures against AMR for sink drainage systems, since NDM producers may have already been hidden in such environments in a non-endemic country of NDM.


Assuntos
Acinetobacter/isolamento & purificação , Hospitais , Infecções por Acinetobacter , Proteínas de Bactérias , Contaminação de Equipamentos , Humanos , Japão , Abastecimento de Água , beta-Lactamases
11.
Zootaxa ; 4624(4): zootaxa.4624.4.4, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31716198

RESUMO

Chelonocytherois omutai gen. et sp. nov., is found on the back of female loggerhead sea turtles on the nesting beach of the Yakushima Island, Kagoshima Prefecture, Japan. The present study provides the first species-level identification and description of Ostracoda as sea turtle epibionts. The new genus and species, which belongs to the family Paradoxostomatidae Brady and Norman, 1889, can clearly be distinguished from other genera by the morphology of the carapace and the appendages. Especially, the quite large sieve structure on the pore system of the carapace is characteristic to this genus. Although a similar structure is also found in the commensal ostracod genus Redekea de Vos, 1953, the new genus has distinctive mandibular and maxillular morphologies. From examination of the appendages, C. omutai gen. et sp. nov. seems to be an epibiotic species associated with sea turtles, but not a strictly commensal species. Additionally, the nearly complete 18S rRNA gene sequence is determined for C. omutai gen. et sp. nov. for future molecular phylogenetic studies. Since the sea turtles migrate across the oceans in their ontogenetic stages, they may play a role as a long-distance dispersal vector for C. omutai gen. et sp. nov.


Assuntos
Tartarugas , Animais , Crustáceos , Feminino , Ilhas , Japão , Oceanos e Mares , Filogenia
12.
Appl Environ Microbiol ; 85(22)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31492666

RESUMO

This study focused on the detection of the plasmid-mediated mcr colistin resistance gene in Escherichia coli isolates from wastewater treatment plants (WWTPs). Seven influent samples were collected from three WWTPs in Nagano Prefecture, Japan, during August and December 2018. Colistin-resistant E. coli isolates were selected on colistin-supplemented CHROMagar ECC plates. mcr-1-positive isolates were subjected to whole-genome sequencing (WGS) analysis. From six influent samples, seven mcr-1-positive but extended-spectrum ß-lactamase (ESBL)-negative isolates belonging to different genetic lineages, namely, B2-O25:H4-ST131-fimH22, B2-O2:H1-ST135-fimH2, B1-O8:H9-ST764-fimH32, B1-O23:H16-ST453-fimH31, A-O81:H27-ST10-fimH54, A-O16:H5-ST871-fimH25, and F-O11:H6-ST457-fimH145, were detected. The MICs of colistin for these isolates ranged from 4 to 16 mg/liter. The mcr-1 genes were located on plasmids belonging to IncX4 and IncI2 in five and two isolates, respectively. Four IncX4 plasmids with the same size (33,309 bp) showed high sequence similarity (4 single-nucleotide variations). The remaining one IncX4 plasmid, with a size of 33,858 bp, carried the mcr-1 gene with the single synonymous nucleic substitution T27C. Two IncI2 plasmids with sizes of 60,710 bp and 60,733 bp had high sequence similarity (99.9% identity; 100% query coverage). Two of five isolates carrying IncX4 plasmids and both of the isolates carrying IncI2 plasmids harbored ColV plasmids carrying virulence-associated genes of avian pathogenic E. coli (APEC). In addition, another isolate of the B2-O25:H4-ST131-fimH22 lineage had those APEC-associated virulence genes on its chromosome. In conclusion, mcr-1-positive E. coli environmental isolates were mostly characterized as positive for APEC-associated virulence genes. The copresence of those genes may suggest the existence of a common source in animals and/or their associated environments.IMPORTANCE Colistin is considered a last-line therapeutic option in severe infections due to multidrug-resistant Gram-negative bacteria, in particular carbapenemase-producing Enterobacteriaceae and multidrug-resistant Acinetobacter baumannii An increasing prevalence of mcr genes in diverse Enterobacteriaceae species, mainly Escherichia coli and Klebsiella pneumoniae from humans and food animals, has become a significant concern to public health all over the world. In Japan, mcr genes have so far been detected in food animals, raw meat, wastewater, and human clinical samples. This study reports the copresence of mcr-1 and avian pathogenic E. coli (APEC)-associated virulence genes in five of seven E. coli isolates recovered from aquatic environments in Japan. Our study highlights the importance and urgency of action to reduce environmental contamination by mcr genes that may likely occur due to exposure to untreated wastewater through combined sewer overflow by recent unusual weather.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/patogenicidade , Fatores de Virulência/genética , Águas Residuárias/análise , Animais , Antibacterianos/farmacologia , Doenças das Aves/microbiologia , Aves/microbiologia , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/isolamento & purificação , Genoma Bacteriano , Japão , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Virulência , Sequenciamento Completo do Genoma
13.
Appl Environ Microbiol ; 85(22)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31519655

RESUMO

The presence of antimicrobial-resistant bacteria and resistance genes in aquatic environments is a serious public health concern. This study focused on Escherichia coli possessing bla CTX-M genes in wastewater inflows. Twelve crude inflow water samples from wastewater treatment plant (WWTP) A and two samples each from three other WWTPs were collected in 2017 and 2018. A total of 73 E. coli isolates with 31 different sequence types (STs) harboring distinctive bla CTX-M gene repertoires were detected. In WWTP A influents, bla CTX-M-14 (14 isolates) was dominant, followed by bla CTX-M-15 (12 isolates) and bla CTX-M-27 (10 isolates). The chimeric bla CTX-M-64 and bla CTX-M-123 genes were each identified in one of the E. coli isolates from the same WWTP A inflow port. The bla CTX-M-27 gene was associated with five of seven B2-ST131 isolates, including three isolates of the B2-O25b-ST131-H30R/non-Rx lineage. One of the remaining two isolates belonged to the B2-O25b-ST131-H30R/Rx lineage harboring the bla CTX-M-15 gene. As for the B2-O25b-ST131-H30R/non-Rx lineage, two isolates with bla CTX-M-27 were recovered from each of the WWTP B and D influents, and one isolate with bla CTX-M-174 was also recovered from WWTP B influent. Whole-genome sequencing of chimeric bla CTX-M-harboring E. coli isolates revealed that the bla CTX-M-64 gene was integrated into the chromosome of ST10 E. coli B22 via ISEcp1-mediated transposition of a 9,467-bp sequence. The bla CTX-M-123-carrying IncI1 plasmid pB64 was 109,169 bp in length with pST108. The overall findings suggest that wastewater may act as a probable reservoir of clinically significant clonal lineages mediating antimicrobial resistance genes and chimeric genes that have not yet been identified from human isolates of domestic origin in Japan.IMPORTANCE Global spread of CTX-M-type extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae is a critical concern in both clinical and community settings. This dominance of CTX-M-type ESBL producers may be largely due to the successful international spread of epidemic clones, as represented by the extraintestinal pathogenic Escherichia coli (ExPEC) ST131. Our findings highlight the worrisome presence of diverse E. coli clones associated with humans, including ExPEC lineages harboring the most common bla CTX-M variants in untreated wastewater samples. Moreover, the chimeric genes bla CTX-M-64 and bla CTX-M-123, which have not yet been identified from human isolates of domestic origin in Japan, were identified. Exposure to untreated wastewater through combined sewer overflow caused by heavy rains derived from abnormal weather change could pose a risk for human health due to ingesting those antimicrobial-resistant bacteria.


Assuntos
Reservatórios de Doenças/microbiologia , Escherichia coli Extraintestinal Patogênica/genética , Genes MDR , Águas Residuárias/análise , beta-Lactamases/genética , Antibacterianos/farmacologia , DNA Bacteriano/genética , Escherichia coli Extraintestinal Patogênica/efeitos dos fármacos , Escherichia coli Extraintestinal Patogênica/enzimologia , Genótipo , Japão , Testes de Sensibilidade Microbiana , Plasmídeos , beta-Lactamases/isolamento & purificação
14.
Microbiol Immunol ; 63(2): 65-76, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30632638

RESUMO

In this study, the selective potential of group B Streptococcus isolates with reduced penicillin susceptibility (PRGBS) in a neonate-hypervirulent sequence type (ST)17 lineage was investigated by in vitro exposure to ß-lactams. After 19 passages of stepwise penicillin exposure, PRGBS with a high penicillin minimum inhibitory concentration MIC (0.5 mg/L), greatly augmented ceftibuten MIC (>512 mg/L), and acquisition of G406D predicted to provide destabilizing effect (ΔΔG 0.099 kcal/mol) on PBP2X structure were identified. In early passages of stepwise cefotaxime exposure, PRGBS possessing G398E predicted to stabilize PBP2X (ΔΔG -0.038 kcal/mol) emerged with high MICs for cefotaxime (0.5 mg/L), ceftibuten (>512 mg/L) and penicillin (0.25 mg/L). Additionally, G398E + G329V + H438Y predicted to provide more stabilizing effect (ΔΔG -0.415 kcal/mol) were detected in mutants with higher MICs to cefotaxime (1 mg/L) and penicillin (0.5 mg/L). PRGBS mutants selected by penicillin and cefotaxime had a marked growth disadvantage compared with the parent strain. After two passages of stepwise ceftibuten exposure, the mutants exhibited increased MICs toward ceftibuten and acquisition of T555S predicted to provide stabilizing effect (ΔΔG -0.111 kcal/mol) in PBP 2X. In subsequent passages, gradual increases in ceftibuten MICs from 128 mg/L to 512 mg/L were found among selected mutants with accompanying stabilizing T555S+A354V (ΔΔG -0.257 kcal/mol) followed by stabilizing T555S + A354V + A536V (ΔΔG -0.322 kcal/mol), resulting in selection of a penicillin-susceptible group B Streptococcus lineage with reduced ceftibuten susceptibility (CTBr PSGBS). Notably, growth ability of CTBr PSGBS mutants was comparable to that of the parent strain. These findings may predict future failure of treatment for neonatal invasive infections caused by the neonate-hypervirulent PRGBS ST17 lineage.


Assuntos
Antibacterianos/farmacologia , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/metabolismo , beta-Lactamas/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cefotaxima/farmacologia , Ceftibuteno/farmacologia , Farmacorresistência Bacteriana Múltipla , Regulação Bacteriana da Expressão Gênica , Humanos , Testes de Sensibilidade Microbiana , Mutação , Proteínas de Ligação às Penicilinas/genética , Proteínas de Ligação às Penicilinas/metabolismo , Penicilinas/farmacologia , Streptococcus agalactiae/genética , Streptococcus agalactiae/crescimento & desenvolvimento
15.
Int J Antimicrob Agents ; 53(3): 203-210, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30414439

RESUMO

Over a 35-month period, group B Streptococcus isolates with reduced penicillin susceptibility (PRGBS) were detected from elderly patients at a regional hospital in Japan, accompanying population-level transition of PRGBS serotypes. The genetic relatedness of 77 non-duplicate PRGBS from 73 patients was analysed. Serotype III PRGBS predominated (16 serotype III/1 serotype Ib) in the first 9 months (period I), then 3 serotype Ib isolates appeared transiently for the next 3 months (period II), which was replaced predominantly by serotype Ia (20 serotype Ia/1 serotype III/1 non-typeable) for 9 months (period III). In the last 14 months (period IV), besides 25 serotype Ia isolates, 10 serotype III were also identified. Serotypes III and Ia isolates, belonging to ST1, shared G329V, G398A, V405A and G429D substitutions in penicillin-binding protein 2X. Of three strains subjected to whole-genome sequencing, serotype III strain SU12 (period I) had a higher degree of genomic similarity with serotype Ia strain SU97 (period III) than serotype Ib strain SU67 (period II) based on average nucleotide identity and single nucleotide polymorphisms. Analysis of the cps gene clusters and the upstream and downstream flanking sequences revealed that disruption of the hyaluronidase gene located upstream of cpsY by insertion of IS1548 was found in strain SU12, whereas ΔISSag8 was inserted between tRNA-Arg and rpsA genes located downstream of cpsL in strain SU97. Interestingly, most serotype III PRGBS re-emerging in period IV had this tRNA-Arg-ΔISSag8-rpsA region. Capsular switching and nosocomial transmission may possibly contribute to population-level serotype replacement among ST1 PRGBS isolates.


Assuntos
Infecção Hospitalar/microbiologia , Epidemias , Evolução Molecular , Polissacarídeos/análise , Sorogrupo , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/classificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Mutação , Resistência às Penicilinas , Polissacarídeos/genética , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Sequenciamento Completo do Genoma
16.
Zootaxa ; 4341(2): 243-257, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29245687

RESUMO

A new apodid sea cucumber, Chiridota impatiens sp. nov., is described from the intertidal zone of Okinawa, Japan, and C. rigida Semper, 1867 is also described from the intertidal zone of Wakayama, as new to Japan. C. impatiens sp. nov. is approximately 60-70 mm, with 12 tentacles and 4-7 pairs of digits per tentacle, red or reddish brown in living specimens. The tentacles contain curved rod ossicles, with spinous processes and many branches in C. rigida, however, in C. impatiens sp. nov., the curved rod ossicles are crescent-shaped, sometimes distally, with spinous processes and rarely a few branches on the circumference. In both species, the body wall contains flattened rod ossicles, mostly present along the longitudinal muscle and mesentery, curved rod ossicles primarily in the body wall, and wheel ossicles only in the wheel-papillae. In C. rigida, the contents of the wheel-papillae form a hemispherical sack-shaped structures, in which the teeth-side of the wheel ossicles mostly faces towards the outside of the body. In C. impatiens sp. nov., the contents of the wheel-papillae form a cord-shaped structure (present in both preserved and living specimens), in which the teeth-side of the wheel ossicles faces various directions, and that can be induced to break through the skin of the papillae if stimulated in living specimens.


Assuntos
Equinodermos , Animais , Japão , Pepinos-do-Mar
17.
Syst Parasitol ; 94(2): 263-274, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28130673

RESUMO

A new commensal ostracod Asterositus ohtsukai n. g., n. sp. (Podocopida: Cytheroidea: Paradoxostomatidae) is described. This new taxon occurs on the ambulacral grooves and wreath of pedicellariae around superomarginal spines of the sea star Sclerasterias euplecta (Fisher) (Asteroidea: Forcipulatida: Asteriidae). Although the family Paradoxostomatidae Brady & Norman, 1889 contains four ectoparasitic or commensal genera, the association with asteroideans has never hitherto been reported. Morphological observations suggested that A. ohtsukai n. g., n. sp. is closely associated with the host sea star as it typically has distal hooks on the antenna and fifth to seventh limbs, and specialised mandibula and maxillula structures that are considered adaptations to a commensal life-style. In addition, this study discussed the feeding habits of A. ohtsukai n. g., n. sp. based on comparison with previous works. The extremely reduced palp and endites of maxillula of A. ohtsukai n. g., n. sp. imply that they have unique feeding habits that are not based on the feeding function of maxillula. From morphological comparisons with siphonostomatoid copepods, we suggest that A. ohtsukai n. g., n. sp. may feed on the body of host sea star by injuring them with styliform needle-like mandibular coxa and sucking the tissues, body fluid, or mucus with the suctorial disc on the oral cone.


Assuntos
Crustáceos/classificação , Crustáceos/fisiologia , Comportamento Alimentar/fisiologia , Estrelas-do-Mar/parasitologia , Animais , Crustáceos/anatomia & histologia , Especificidade da Espécie
18.
Zoolog Sci ; 33(6): 659-666, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927102

RESUMO

A new species of the cyclopinid genus Cyclopicina, C. toyoshioae sp. nov., was collected from the hyperbenthic layer off northern Kyushu Island, Japan; its description is based on two adult female specimens. This is the first record of the genus from the Indo-Pacific region. The new species can be distinguished from its two known congeners in: (1) the relatively short antennules which do not reach the posterior margin of the dorsal cephalothoracic shield; (2) the shape of seminal receptacles; (3) the segmentation and armature of the cephalothoracic appendages; (4) the shape of the basal protrusion between the rami of legs 1-4; (5) the presence of three outer spines on the third exopodal segment of leg 4; and (6) the presence or absence of outer setae on the free exopodal segment of leg 5. The genus Cyclopicina shows a wide but scattered distribution in hyperbenthic layers, from the continental shelves to deep-sea basins, in the northern hemisphere.


Assuntos
Copépodes/anatomia & histologia , Copépodes/classificação , Distribuição Animal , Animais , Feminino , Japão , Oceano Pacífico , Especificidade da Espécie
19.
Zoolog Sci ; 33(5): 555-565, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27715418

RESUMO

Deep-sea hydrothermal vent fields are among the most extreme habitats on Earth. Major research interests in these ecosystems have focused on the anomalous macrofauna, which are nourished by chemoautotrophic bacterial endosymbionts. In contrast, the meiofauna is largely overlooked in this chemosynthetic environment. The present study describes a new species, Thomontocypris shimanagai sp. nov. (Crustacea: Ostracoda), which was collected from the surface of colonies of neoverrucid barnacles and paralvinellid worms on the chimneys at the Myojin-sho submarine caldera. This is the first discovery of an ostracode from deep-sea hydrothermal vent environments in the western Pacific region. In addition to the species description, we discuss three aspects: 1) adaptation, 2) endemism, and 3) dispersal strategy of the hydrothermal vent ostracodes. Regarding these aspects, we conclude the following: 1) the new species may feed on sloughed-off tissues, mucus secretions, or fecal pellets of sessile organisms, rather than depend on chemoautotrophic bacteria as symbionts for energy; 2) as has been pointed out by other studies, Thomontocypris does not likely represent a vent-specific genus; however, this new species is considered to be endemic at the species level, as it has not been found outside of the type locality; and 3) this new species may have migrated from adjacent deep-sea chemosynthesis-based habitats, such as hydrothermal vents, with wood falls potentially having acted as stepping stones.


Assuntos
Adaptação Fisiológica , Distribuição Animal/fisiologia , Crustáceos/classificação , Fontes Hidrotermais , Animais , Crustáceos/anatomia & histologia , Crustáceos/genética , Oceano Pacífico , Especificidade da Espécie
20.
Zookeys ; (607): 25-35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551228

RESUMO

A new species of the priscomilitarid amphipod, Priscomilitaris heike, from the Seto Inland Sea, Japan, is named and described. This new species is the third species of Priscomilitaridae and the second species of Priscomilitaris. Additionally, nucleotide sequences of nuclear 28S rRNA and histone H3 as well as mitochondrial cytochrome c oxidase subunit I from its holotype were determined. Priscomilitaris heike sp. n. is distinguished from its congener, Priscomilitaris tenuis Hirayama, 1988, by having deep antennal sinus, long flagellar article 1 of antennae 1 and 2, long mandibular palp article 2, 10 robust setae on outer ramus of maxilla 1, and rounded epimeral plates. A key to the species of Proscomilitaridae is provided.

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