RESUMEN
Plant pathogenic bacteria have developed effectors to manipulate host cell functions to facilitate infection. A certain number of effectors use the conserved ubiquitin-proteasome system in eukaryotic to proteolyze targets. The proteasome utilization mechanism is mainly mediated by ubiquitin interaction with target proteins destined for degradation. Phyllogens are a family of protein effectors produced by pathogenic phytoplasmas that transform flowers into leaves in diverse plants. Here, we present a noncanonical mechanism for phyllogen action that involves the proteasome and is ubiquitin-independent. Phyllogens induce proteasomal degradation of floral MADS-box transcription factors (MTFs) in the presence of RADIATION-SENSITIVE23 (RAD23) shuttle proteins, which recruit ubiquitinated proteins to the proteasome. Intracellular localization analysis revealed that phyllogen induced colocalization of MTF with RAD23. The MTF/phyllogen/RAD23 ternary protein complex was detected not only in planta but also in vitro in the absence of ubiquitin, showing that phyllogen directly mediates interaction between MTF and RAD23. A Lys-less nonubiquitinated phyllogen mutant induced degradation of MTF or a Lys-less mutant of MTF. Furthermore, the method of sequential formation of the MTF/phyllogen/RAD23 protein complex was elucidated, first by MTF/phyllogen interaction and then RAD23 recruitment. Phyllogen recognized both the evolutionarily conserved tetramerization region of MTF and the ubiquitin-associated domain of RAD23. Our findings indicate that phyllogen functionally mimics ubiquitin as a mediator between MTF and RAD23.
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Phytoplasma , Proteínas de Saccharomyces cerevisiae , Flores/metabolismo , Phytoplasma/metabolismo , Plantas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ubiquitina/metabolismoRESUMEN
Vertebrate Hox clusters are comprised of multiple Hox genes that control morphology and developmental timing along multiple body axes. Although results of genetic analyses using Hox-knockout mice have been accumulating, genetic studies in other vertebrates have not been sufficient for functional comparisons of vertebrate Hox genes. In this study, we isolated all of the seven hox cluster loss-of-function alleles in zebrafish using the CRISPR-Cas9 system. Comprehensive analysis of the embryonic phenotype and X-ray micro-computed tomography scan analysis of adult fish revealed several species-specific functional contributions of homologous Hox clusters along the appendicular axis, whereas important shared general principles were also confirmed, as exemplified by serial anterior vertebral transformations along the main body axis, observed in fish for the first time. Our results provide insights into discrete sub/neofunctionalization of vertebrate Hox clusters after quadruplication of the ancient Hox cluster. This set of seven complete hox cluster loss-of-function alleles provide a formidable resource for future developmental genetic analysis of the Hox patterning system in zebrafish.
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Genes Homeobox/genética , Familia de Multigenes , Pez Cebra/genética , Pez Cebra/fisiología , Animales , Sistemas CRISPR-Cas , Desarrollo Embrionario/genética , Evolución Molecular , Femenino , Duplicación de Gen , Regulación del Desarrollo de la Expresión Génica , Masculino , Mutación , Esqueleto/anatomía & histología , Esqueleto/crecimiento & desarrollo , Especificidad de la Especie , Microtomografía por Rayos X , Pez Cebra/embriologíaRESUMEN
Plant viruses depend on a number of host factors for successful infection. Deficiency of critical host factors confers recessively inherited viral resistance in plants. For example, loss of Essential for poteXvirus Accumulation 1 (EXA1) in Arabidopsis thaliana confers resistance to potexviruses. However, the molecular mechanism of how EXA1 assists potexvirus infection remains largely unknown. Previous studies reported that the salicylic acid (SA) pathway is upregulated in exa1 mutants, and EXA1 modulates hypersensitive response-related cell death during EDS1-dependent effector-triggered immunity. Here, we show that exa1-mediated viral resistance is mostly independent of SA and EDS1 pathways. We demonstrate that Arabidopsis EXA1 interacts with three members of the eukaryotic translation initiation factor 4E (eIF4E) family, eIF4E1, eIFiso4E, and novel cap-binding protein (nCBP), through the eIF4E-binding motif (4EBM). Expression of EXA1 in exa1 mutants restored infection by the potexvirus Plantago asiatica mosaic virus (PlAMV), but EXA1 with mutations in 4EBM only partially restored infection. In virus inoculation experiments using Arabidopsis knockout mutants, EXA1 promoted PlAMV infection in concert with nCBP, but the functions of eIFiso4E and nCBP in promoting PlAMV infection were redundant. By contrast, the promotion of PlAMV infection by eIF4E1 was, at least partially, EXA1 independent. Taken together, our results imply that the interaction of EXA1-eIF4E family members is essential for efficient PlAMV multiplication, although specific roles of three eIF4E family members in PlAMV infection differ. IMPORTANCE The genus Potexvirus comprises a group of plant RNA viruses, including viruses that cause serious damage to agricultural crops. We previously showed that loss of Essential for poteXvirus Accumulation 1 (EXA1) in Arabidopsis thaliana confers resistance to potexviruses. EXA1 may thus play a critical role in the success of potexvirus infection; hence, elucidation of its mechanism of action is crucial for understanding the infection process of potexviruses and for effective viral control. Previous studies reported that loss of EXA1 enhances plant immune responses, but our results indicate that this is not the primary mechanism of exa1-mediated viral resistance. Here, we show that Arabidopsis EXA1 assists infection by the potexvirus Plantago asiatica mosaic virus (PlAMV) by interacting with the eukaryotic translation initiation factor 4E family. Our results imply that EXA1 contributes to PlAMV multiplication by regulating translation.
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Proteínas de Arabidopsis , Arabidopsis , Factor 4E Eucariótico de Iniciación , Enfermedades de las Plantas , Potexvirus , Arabidopsis/metabolismo , Arabidopsis/virología , Factor 4E Eucariótico de Iniciación/genética , Factor 4E Eucariótico de Iniciación/metabolismo , Enfermedades de las Plantas/genética , Potexvirus/fisiología , Proteínas de Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Unión Proteica , Secuencias de Aminoácidos , Eliminación de Gen , Células Vegetales/virología , Biosíntesis de Proteínas/genéticaRESUMEN
We constructed a hyperspectral circular polarization (S3) imaging system in the near-infrared (NIR) region comprising a circularly polarized broadband light source, a polarization grating, and a commercial hyperspectral camera. With this system, we captured hyperspectral S3 images of plastic samples. We then demonstrated the classification with machine learning and found that the hyperspectral S3 images showed higher classification precision than the conventional NIR hyperspectral images. This result indicates that the hyperspectral S3 imaging has potential for object classification even for samples with similar absorption spectra. This hyperspectral S3 imaging system can be applied in garbage classification in recycling plants.
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Controlling the birefringence of optical films is imperative to fabricate thin birefringent optical devices. Here, new photoalignable liquid crystalline copolymers (PLCPs) with 4-formylphneyl benzoate (PA) and cinnamic acid (CA) side groups are synthesized, which attain high photoreactivity and controllability of the orientation direction. Additionally, the exposed films are treated with 2-aminofluorene (AF) for an in situ condensation of PA with AF to form a Schiff base with a high inherent birefringence. Birefringence of the photoaligned film can be controlled up to 0.45 without disturbing the photoinduced orientation structure.
RESUMEN
A lot of research on liquid crystal polarization gratings (LCPGs) that can separate circularly polarized light with 100% diffraction efficiency has been conducted in the visible and near-infrared wavelength regions. In this paper, we tried to design and fabricate the LCPGs that are available for use in the mid- and far-infrared (MIR and FIR) wavelength regions. The materials for making LCPGs were selected in view of low absorption characteristics measured by the use of a Fourier-transform infrared (FT-IR) spectrometer. LCPGs designed for 3.88 µm and 9.5-10.6 µm were fabricated, and we evaluated their diffraction properties experimentally. The MIR and FIR LCPGs should open new application fields of LC technologies including polarimetry, spectroscopy, and beam steering.
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This study uses a generative adversarial network to design multilevel optical anisotropic diffraction gratings with specific customizable characteristics. As input, this method uses the far electric field of polarization and intensity in each diffracted light through the gratings to design. Using the finite-difference time-domain method, the designed structures are numerically evaluated, confirming that they can be created with the intended parameters. Multilevel optical anisotropic diffraction gratings created this way can be used in various fields to develop improved optical elements.
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Helicobacter suis, a bacterial species naturally hosted by pigs, can colonize the human stomach in the context of gastric diseases such as gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Because H. suis has been successfully isolated from pigs, but not from humans, evidence linking human H. suis infection to gastric diseases has remained incomplete. In this study, we successfully in vitro cultured H. suis directly from human stomachs. Unlike Helicobacter pylori, the viability of H. suis decreases significantly on neutral pH; therefore, we achieved this using a low-pH medium for transport of gastric biopsies. Ultimately, we isolated H. suis from three patients with gastric diseases, including gastric MALT lymphoma. Successful eradication of H. suis yielded significant improvements in endoscopic and histopathological findings. Oral infection of mice with H. suis clinical isolates elicited gastric and systemic inflammatory responses; in addition, progression of gastric mucosal metaplasia was observed 4 mo postinfection. Because H. suis could be isolated from the stomachs of infected mice, our findings satisfied Koch's postulates. Although further prospective clinical studies are needed, H. suis, like H. pylori, is likely a gastric pathogen in humans. Furthermore, comparative genomic analysis of H. suis using complete genomes of clinical isolates revealed that the genome of each H. suis isolate contained highly plastic genomic regions encoding putative strain-specific virulence factors, including type IV secretion system-associated genes, and that H. suis isolates from humans and pigs were genetically very similar, suggesting possible pig-to-human transmission.
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Infecciones por Helicobacter/genética , Helicobacter heilmannii/genética , Helicobacter heilmannii/patogenicidad , Gastropatías/microbiología , Estómago/microbiología , Factores de Virulencia/genética , Adulto , Animales , Modelos Animales de Enfermedad , Femenino , Genoma Bacteriano , Helicobacter heilmannii/aislamiento & purificación , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Porcinos , Sistemas de Secreción Tipo IV/genética , Virulencia/genéticaRESUMEN
Mast cells take up extracellular latent heparanase and store it in secretory granules. The present study examined whether the enzymatic activity of heparanase regulates its uptake efficiency. Recombinant mouse heparanase mimicking both the latent and mature forms (L-Hpse and M-Hpse, respectively) was internalized into mastocytoma MST cells, peritoneal cell-derived mast cells, and bone marrow-derived mast cells. The internalized amount of L-Hpse was significantly higher than that of M-Hpse. In MST cells, L-Hpse was continuously internalized for up to 8 h, while the uptake of M-Hpse was saturated after 2 h of incubation. L-Hpse and M-Hpse are similarly bound to the MST cell surface. The expression level of cell surface heparan sulfate was reduced in MST cells incubated with M-Hpse. The internalized amount of M-Hpse into mast cells was significantly increased in the presence of heparastatin (SF4), a small molecule heparanase inhibitor that does not affect the binding of heparanase to immobilized heparin. Enzymatically quiescent M-Hpse was prepared with a point mutation at Glu335. The internalized amount of mutated M-Hpse was significantly higher than that of wild-type M-Hpse but similar to that of wild-type and mutated L-Hpse. These results suggest that the enzymatic activity of heparanase negatively regulates the mast cell-mediated uptake of heparanase, possibly via the downregulation of cell surface heparan sulfate expression.
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Glucuronidasa , Heparitina Sulfato , Mastocitos , Mastocitos/metabolismo , Glucuronidasa/metabolismo , Glucuronidasa/genética , Animales , Heparitina Sulfato/metabolismo , Ratones , Línea Celular TumoralRESUMEN
We report the isolation of Helicobacter ailurogastricus, a Helicobacter species that infects cats and dogs, from a person with multiple refractory gastric ulcers. In addition to H. suis, which infects pigs, Helicobacter species that infect cats and dogs should be considered as potential gastric pathogens in humans.
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Infecciones por Helicobacter , Helicobacter heilmannii , Helicobacter , Úlcera Gástrica , Humanos , Animales , Gatos , Perros , Porcinos , Úlcera Gástrica/diagnóstico , Japón , Helicobacter heilmannii/genética , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/veterinaria , Helicobacter/genéticaRESUMEN
Antimicrobial resistance (AMR) of bacterial pathogens, including enterococci, is a global concern, and plasmids are crucial for spreading and maintaining AMR genes. Plasmids with linear topology were identified recently in clinical multidrug-resistant enterococci. The enterococcal linear-form plasmids, such as pELF1, confer resistance to clinically important antimicrobials, including vancomycin; however, little information exists about their epidemiological and physiological effects. In this study, we identified several lineages of enterococcal linear plasmids that are structurally conserved and occur globally. pELF1-like linear plasmids show plasticity in acquiring and maintaining AMR genes, often via transposition with the mobile genetic element IS1216E. This linear plasmid family has several characteristics enabling long-term persistence in the bacterial population, including high horizontal self-transmissibility, low-level transcription of plasmid-carried genes, and a moderate effect on the Enterococcus faecium genome alleviating fitness cost and promoting vertical inheritance. Combining all of these factors, the linear plasmid is an important factor in the spread and maintenance of AMR genes among enterococci.
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Enterococcus faecium , Infecciones por Bacterias Grampositivas , Humanos , Enterococcus faecium/genética , Antibacterianos/farmacología , Enterococcus , Plásmidos/genética , Vancomicina/farmacología , Infecciones por Bacterias Grampositivas/microbiologíaRESUMEN
This study presents the reassessment of earlier published data with reference to the article published in Environmental Microbiology entitled 'IncP-type plasmids carrying genes for antibiotic resistance or aromatic compound degradation are prevalent in sequenced Aromatoleum and Thauera strains' by Lo et al. This correspondence clarifies misperceptions of plasmids classified under incompatibility (Inc) groups IncP-1 and IncP-11.
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Microbiología Ambiental , Plásmidos/genética , Secuencia de Bases , Farmacorresistencia Microbiana/genéticaRESUMEN
We detected a virus-like sequence in Cynanchum rostellatum leaves showing yellow mottle symptoms, found in Tokyo, Japan. RNA-Seq analysis revealed that the complete nucleotide sequence of the virus genome was 5,878 nucleotides in length and that it contained seven open reading frames (ORFs) specific to members of the genus Polerovirus. Accordingly, phylogenetic analysis revealed that the virus clustered with poleroviruses in the family Solemoviridae. The amino acid sequence identity values obtained by comparison of the deduced proteins of this virus and those of known members of the genus Polerovirus were lower than 90%, which is the species demarcation criterion of the taxon. The results indicate that this virus is a novel member of the genus Polerovirus, for which the name "cynanchum yellow mottle-associated virus" is proposed.
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Cynanchum , Luteoviridae , Luteoviridae/genética , Cynanchum/genética , Filogenia , ARN Viral/genética , Enfermedades de las Plantas , Genoma Viral , Sistemas de Lectura AbiertaRESUMEN
Despite frequent identification of plasmids carrying carbapenemase genes, the transfer of plasmids carrying carbapenemase genes is not well recognized in clinical settings because of technical limitations. To investigate the detailed mechanisms of the spread of carbapenem-resistant Enterobacteriaceae (CRE), we performed multifaceted genomic surveillance of CRE isolates in Thailand and analyzed their plasmidome. We analyzed 371 Enterobacteriaceae isolates carrying blaNDM-1 and 114 Enterobacteriaceae isolates carrying blaNDM-5 obtained from clinical samples of 473 patients in 11 representative hospitals located in six provinces in Thailand between 2012 and 2017. The complete structures of plasmids carrying blaNDM and chromosomal phylogeny were determined by combining Southern blotting hybridization analysis and our previously performed whole-genome short-read sequencing data. Dissemination of the blaNDM-5 gene among the Enterobacteriaceae isolates in Thailand was mainly owing to the nationwide clonal spread of Escherichia coli ST410 and regional clonal spreads of Escherichia coli ST361 and ST405. Analysis of blaNDM-1-carrying isolates revealed nationwide dissemination of two specific plasmids and nationwide clonal dissemination of Klebsiella pneumoniae ST16 accompanied with regional disseminations of three distinctive K. pneumoniae clones (ST231, ST14, and ST147) with different plasmids. Dissemination of CRE carrying blaNDM in Thailand is mainly based on nationwide clonal expansions of E. coli ST410 carrying blaNDM-5 and K. pneumoniae ST16 carrying blaNDM-1, nationwide dissemination of two distinctive plasmids carrying blaNDM-1, and accumulation of clonal expansions in regional areas. Although the overuse of antibiotics can promote CRE dissemination, the limited variety of transmitters highlights the importance of preventing horizontal dissemination among patients.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Enterobacteriaceae , Humanos , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Escherichia coli/genética , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Tailandia/epidemiología , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , Enterobacteriaceae/genética , Plásmidos/genética , Klebsiella pneumoniae/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéuticoRESUMEN
INTRODUCTION: ß-ray strontium-89 (Sr-89) intra-irradiation therapy has been approved and clinically used to reduce bone metastasis pain not alleviated by bone-modifying agents, external radiation, and analgesic agents. We examined the efficacy of zoledronic acid (ZOL) and Sr-89 combination therapy compared with ZOL alone in breast cancer patients with bone metastases. MATERIALS AND METHODS: A randomized controlled trial was conducted on breast cancer patients with bone metastasis to compare the efficacy between ZOL monotherapy and ZOL plus Sr-89 combination therapy. The primary endpoints were changes in urinary NTX levels at 13 weeks and brief pain inventory scores. The secondary endpoints were analgesic drug usages, response rates, changes in bone metabolism markers, quality of life, and adverse event rates. RESULTS: Thirty of the planned 60 cases were randomly assigned to ZOL alone or ZOL + Sr-89. There were no significant differences in the changes in urinary NTX levels between the 2 groups (P = 0.365). There was no consistent difference in the pain score changes between the 2 groups. Sr-89 addition to ZOL slightly reduced the white blood cell and platelet counts. However, all adverse events were Grade 1. Safety and analgesic drug dose reduction were more evident in ZOL + Sr-89. CONCLUSION: This trial showed the lack of benefits from Sr-89 addition to ZOL for breast cancer patients with painful bone metastases. However, safety and analgesic drug dose reduction were more evident in ZOL + Sr-89, indicating its potential for pain control. Sr-89 therapy is safe, thus more effective radiopharmaceuticals are anticipated.
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Conservadores de la Densidad Ósea , Neoplasias Óseas , Neoplasias de la Mama , Humanos , Femenino , Ácido Zoledrónico/uso terapéutico , Difosfonatos/efectos adversos , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Calidad de Vida , Imidazoles/efectos adversos , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Dolor/tratamiento farmacológico , Dolor/etiología , Conservadores de la Densidad Ósea/efectos adversosRESUMEN
Fatsia japonica is an evergreen shrub native to Japan. For decades, virus-like ringspot symptoms have been observed on leaves of F. japonica in Japan; however, previous attempts to identify the causal agents have been unsuccessful. In this study, we detected an orthotospovirus-like sequence in symptomatic F. japonica plants using RNA sequencing analysis. The complete nucleotide sequences of the L, M, and S segments of the virus were determined using conventional sequencing strategies. The virus had a typical orthotospovirus genome structure, and the putative nucleocapsid protein showed the highest sequence identity to that of groundnut chlorotic fan-spot virus, with 83.7% identity at the amino acid level (which is below the 90% species demarcation cutoff for the genus Orthotospovirus). Although we could not confirm the pathogenicity of the virus in F. japonica due to difficulties associated with mechanical inoculation, its association with the observed symptoms was suggested by the fact that the virus was detected only in symptomatic leaf areas. Based on these results, we consider this virus, which we have named "Fatsia japonica ringspot-associated virus" (FjRSaV), to be the first representative of a new orthotospovirus species, for which we propose the binomial "Orthotospovirus fatsiae".
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Enfermedades de las Plantas , Virus ARN , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Análisis de Secuencia de ADNRESUMEN
OBJECTIVES: For suspected common bile duct stone (CBDS) missed on computed tomography (CT), there is no clear evidence on whether endoscopic ultrasound (EUS) or magnetic resonance cholangiopancreatography (MRCP) is the better diagnostic tool. We aimed to compare the diagnostic accuracy of EUS and MRCP for cases of missed CBDS on CT. METHODS: Patients suspected of having CBDS were enrolled and randomly allocated to the EUS or MRCP group. Upon the initial examination, those having CBDS or sludge formation underwent endoscopic retrograde cholangiopancreatography (ERCP), while those who were CBDS-negative underwent a second examination with either MRCP or EUS, which was distinct from the initial diagnostic procedure. The primary outcome was diagnostic accuracy, and the secondary outcomes were diagnostic ability, detection rate and characteristics of CBDS in the second examination, and the frequency of adverse events. RESULTS: Between April 2019 and January 2021, 50 patients were enrolled in the study. The accuracy was 92.3% for EUS and 68.4% for MRCP (P = 0.055). EUS showed 100% sensitivity, 88.2% specificity, 81.8% positive predictive value, and 100% negative predictive value, and MRCP showed 33.3% sensitivity, 84.6% specificity, 50% positive predictive value, and 73.3% negative predictive value. The CBDS detection rate in the second examination was 0% for MRCP after a negative EUS and 35.7% for EUS after a negative MRCP (P = 0.041). No adverse events occurred in any of the patients. CONCLUSIONS: Endoscopic ultrasound may be a superior diagnostic tool compared to MRCP for the detection of CBDS that are undetected on CT. (UMIN000036357).
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Coledocolitiasis , Cálculos Biliares , Colangiopancreatografia Retrógrada Endoscópica/métodos , Pancreatocolangiografía por Resonancia Magnética/métodos , Conducto Colédoco , Endosonografía/métodos , Cálculos Biliares/diagnóstico por imagen , Humanos , Estudios Prospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: USA300 produces Panton-Valentin leucocidin (PVL) and is known as a predominant community-associated methicillin-resistant Staphylococcus aureus (MRSA) strain in the United States, but it was extremely rare in Japan. We report here an outbreak of USA300 in people with HIV (PWH) in Tokyo, Japan. METHODS: We analyzed the cases of PVL-MRSA infection between 2010 and 2020 and screened for nasal colonization of PVL-MRSA in PWH who visited an HIV/AIDS referral hospital from December 2019 to March 2020. Whole-genome sequencing-based single nucleotide polymorphism (SNP) analysis was performed on these isolates. RESULTS: During the study period, a total of 21 PVL-MRSA infections in 14 patients were identified after 2014. The carriage prevalence was 4.3% (12/277) and PVL-MRSA carriers were more likely to have sexually transmitted infections (STIs) within a year compared with patients who had neither a history of PVL-MRSA infection nor colonization (33.3% [4/12] vs 10.1% [26/258]; Pâ =â .03). SNP analysis showed that all 26 isolates were ST8-SCCmecIVa-USA300. Twenty-four isolates were closely related (≤100 SNP differences) and had the nonsynonymous SNPs associated with carbohydrate metabolism and antimicrobial tolerance. CONCLUSIONS: An outbreak of USA300 has been occurring among PWH in Tokyo and a history of STI was a risk of colonization.
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Brotes de Enfermedades , Infecciones por VIH/complicaciones , Homosexualidad Masculina , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Portador Sano , Farmacorresistencia Bacteriana Múltiple , Genoma Bacteriano , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Persona de Mediana Edad , Tipificación Molecular , Nariz/microbiología , Filogenia , Polimorfismo de Nucleótido Simple , Prevalencia , Estudios Retrospectivos , Enfermedades de Transmisión Sexual/complicaciones , Infecciones Estafilocócicas/complicaciones , Tokio/epidemiología , Factores de Virulencia/análisis , Secuenciación Completa del Genoma , Adulto JovenRESUMEN
Mycobacterium avium subspecies hominissuis (MAH) is a pathogen that causes various non-tuberculous mycobacterial diseases in humans and animals worldwide. Among the genus, MAH is characterized by relatively slow growth. Here, we isolated a rapidly growing variant of the MAH 104 strain. The variant strain (named N104) exhibited an enhanced growth rate and higher motility compared to the parent MAH 104 strain (P104). Whole-genome sequencing analysis of N104 revealed the loss of the stop codon of MAV_RS14660 due to a single nucleotide replacement, resulting in the substitution of the codon for tryptophan. Notably, exclusion of the stop codon ligated the open reading frames and caused the fusion of two adjacent proteins. A revertant parent strain, in which a mutation was introduced to restore the stop codon, revealed that elimination of the stop codon in MAV_RS14660 was responsible for the N104 phenotype. Furthermore, we analysed the phenotypes of the parent and mutated strains by determining the functions of the MAV_RS14660 and MAV_RS14655 coding regions flanking the stop codon. The mutant strains, expected to express a fusion protein, exhibited increased resistance to antimicrobial drugs and exogenous copper toxicity compared to that of the parent strains. These findings suggest that the fusion of the MAV_RS14660- and MAV_RS14655-encoding regions in the mutant N104 strain could be related to the modified functions of these intrinsic proteins.
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Proteínas Bacterianas/genética , Mycobacterium/crecimiento & desarrollo , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Codón de Terminación/genética , Cobre/farmacología , Farmacorresistencia Bacteriana/genética , Genoma Bacteriano/genética , Humanos , Locomoción/genética , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Mycobacterium/efectos de los fármacos , Mycobacterium/genética , Infecciones por Mycobacterium/microbiología , Mutación PuntualRESUMEN
New ester-functionalized bicyclic aliphatic polymers are synthesized through the ring-opening metathesis polymerization (ROMP) of endo- and exo-norbornene lactones (endo-NBL and exo-NBL) and their oxa-norbornene analogue (exo-oxa-NBL) followed by hydrogenation. The polymerizability between endo- and exo-NBLs, and the thermal properties between the six types of polymers before and after hydrogenation are compared and discussed. The ROMP of all three monomers proceeded in a living fashion under optimized conditions, which is confirmed by chain extension experiments. Endo-NBL shows a much lower homo- and copolymerizability than exo-NBL probably owing to six-membered chelation to the Ru center and steric hindrance in the ruthenacyclobutane intermediate. Stereo-block and stereo-gradient copolymers of poly(endo-NBL) and poly(exo-NBL) are also synthesized. The hydrogenation catalyzed by RuHCl(CO)(PPh3 )3 in the mixed solvents of o-xylene and N,N-dimethyl acetamide (DMAc) results in more than 95% conversion. The obtained hydrogenated polymers, H-poly(endo-NBL) and H-poly(exo-NBL), are amorphous, soluble in chlorinated aliphatic solvents, and thermally stable until 400 °C without a weight loss. Their glass transition temperatures are 163 and 131 °C, respectively; the values are appropriate in terms of both thermal stability and processing deformation for the application of transparent resin materials.