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1.
Adv Sci (Weinh) ; : e2309003, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828764

RESUMO

Applying lattice strain to thin films, a critical factor to tailor their properties such as stabilizing a structural phase unstable at ambient pressure, generally necessitates heteroepitaxial growth to control the lattice mismatch with substrate. Therefore, while homoepitaxy, the growth of thin film on a substrate made of the same material, is a useful method to fabricate high-quality thin films, its application to studying strain-induced structural phases is limited. Contrary to this general belief, here the quasi-homoepitaxial growth of Cs and Rb thin films is reported with substantial in-plane compressive strain. This is achieved by utilizing the alkali-metal layer existing in bulk crystal of kagome metals AV3Sb5 (A = Cs and Rb) as a structural template. The angle-resolved photoemission spectroscopy measurements reveal the formation of metallic quantum well states and notable thickness-dependent quasiparticle lifetime. Comparison with density functional theory calculations suggests that the obtained thin films crystalize in the face-centered cubic structure, which is typically stable only under high pressure in bulk crystals. These findings provide a useful approach for synthesizing highly strained thin films by quasi-homoepitaxy, and pave the way for investigating many-body interactions in Fermi liquids with tunable dimensionality.

2.
Microbiol Resour Announc ; : e0021924, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742884

RESUMO

We report seven draft genome sequences of Streptococcus canis strains revealing reduced penicillin-G susceptibility. The genomes measured 2.054-2.385 Mbp, with G+C contents of 38.8%-39.6%. Amino acid substitutions in penicillin-binding proteins were characterized as compared with those of NCTC 12191(T) genome sequence (GenBank accession number NZ_LR134293.1).

3.
BMC Res Notes ; 17(1): 138, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750516

RESUMO

OBJECTIVE: The purpose of this study was to identify the M protein trans-acting positive regulator (Mga) orthologue and its adjacent M-like protein (SCM) alleles in Streptococcus canis. RESULTS: Using the 39 SCM allele isolates and polymerase chain reaction-based amplification and sequencing, we obtained the deduced Mga amino acid (AA) sequences. The 22 Mga sequences in whole-genome sequences were obtained by searching the National Collection of Type Cultures 12,191(T) Mga sequence into the database. The percentage identity to the type-strain Mga sequence was examined along with its size. The presence of the Mga-specific motifs was confirmed. Of the 62 strains, we identified 59 Mga sequences with an AA size of 509 (except for four different sizes). Percentage identity ranged from 96.66 to 100% with the confirmed Mga-specific motifs and diverse SCM allele populations. Our findings support the presence of an Mga orthologue and diverse SCM allele populations.


Assuntos
Alelos , Proteínas de Bactérias , Streptococcus , Streptococcus/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Aminoácidos
4.
J Vet Med Sci ; 86(5): 468-473, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38569837

RESUMO

Streptococcus uberis is one of major pathogens causing bovine mastitis. However, there is poor information on antimicrobial resistance (AMR) among the Japanese isolates. To provide treatment information for the mastitis caused by S. uberis in Japan, we aimed to clarify AMR patterns of the isolates from bovine milk mainly in Chiba. AMR phenotyping/genotyping [blaZ-erm(A)-erm(B)-mef(A)-linB-lnuD-tet(M)-tet(O)-tet(K)-tet(L)-tet(S)] and multilocus sequence typing were performed to analyze relationships between AMR patterns and clonal complexes (CCs). Resistance to tetracycline-, macrolide-, and lincosamide-classes was mainly associated with possession of tet(O), tet(S), erm(B), linB, and lnuD genes. CC996 was significantly associated with multidrug resistance (P<0.0001). These findings will aid Chiba farm animal clinics in treating bovine mastitis.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana Múltipla , Mastite Bovina , Leite , Infecções Estreptocócicas , Streptococcus , Animais , Bovinos , Streptococcus/efeitos dos fármacos , Streptococcus/genética , Streptococcus/isolamento & purificação , Japão , Leite/microbiologia , Mastite Bovina/microbiologia , Feminino , Antibacterianos/farmacologia , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/tratamento farmacológico , Tipagem de Sequências Multilocus , Genótipo , Testes de Sensibilidade Microbiana
5.
IDCases ; 35: e01927, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303733

RESUMO

Streptococcal toxic shock syndrome (STSS) has a dramatic clinical course and high mortality rate. Here, we report a case of STSS complicated by primary peritonitis and bilateral empyema. A previously healthy young woman was diagnosed with STSS complicated by primary peritonitis and bilateral empyema. Blood culture results on admission were negative. Sever shock, respiratory failure, systemic inflammation, thrombocytopenia, renal failure, ascites, and pleural effusion occurred, mimicking thrombocytopenia, anasarca, fever, reticulin fibrosis/renal failure and organomegaly (TAFRO) syndrome. Retesting blood cultures identified Streptococcus pyogenes. Gram staining of ascites and pleural fluid indicated gram-positive cocci in chains. Antibiotics, immunoglobulins, and surgical intervention led to recovery without complications. Ex-post genotypic analyses showed uncommon emm103.0 (cluster E3) of emm long sequence (784 base) and novel sequence type 1363. STSS diagnosis can be difficult as it mimics other systemic inflammatory diseases. Therefore, it is crucial for clinicians to perform microbiological examinations from infection foci, even if the initial culture is negative.

6.
Microbiol Resour Announc ; 13(2): e0102723, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38289051

RESUMO

We report the draft genome sequence of Streptococcus pyogenes strain AB1 isolated from the blood of a woman with peritonitis-toxic shock syndrome. The genome measured 1.855 Mbp, with a G + C content of 38.3%. Sequences unmapped to the reference genome sequence of M1 SF370 (GenBank accession number AE004092.2) were characterized.

7.
Acad Radiol ; 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38286723

RESUMO

Radiomics uses advanced mathematical analysis of pixel-level information from radiologic images to extract existing information in traditional imaging algorithms. It is intended to find imaging biomarkers related to the genomics of tumors or disease patterns that improve medical care by advanced detection of tumor response patterns in tumors and to assess prognosis. Radiomics expands the paradigm of medical imaging to help with diagnosis, management of diseases and prognostication, leveraging image features by extracting information that can be used as imaging biomarkers to predict prognosis and response to treatment. Radiogenomics is an emerging area in radiomics that investigates the association between imaging characteristics and gene expression profiles. There are an increasing number of research publications using different radiomics approaches without a clear consensus on which method works best. We aim to describe the workflow of radiomics along with a guide of what to expect when starting a radiomics-based research project.

8.
Jpn J Infect Dis ; 77(1): 25-33, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-37779027

RESUMO

We evaluated the cell invasion ability (CIA) of non-invasive Streptococcus dysgalactiae subsp. equisimilis using human keratinocytes and determined the association of CIA populations with their hosts and microbiological traits. Forty-two isolates from humans and companion animals were selected with host information. In addition to CIA, virulence-associated gene (VAG, spegg-ska-scpA-inlA-sicG-brpA-prtF1-prtF2-lmb-cbp-srtp1-srtp2) profiling, emm genotyping, multilocus sequence typing, and antimicrobial resistance (AMR) phenotyping/genotyping were performed. We designated CIA values higher than the mean of all isolates as high-frequency and those lower than the mean as low-frequency. Differences in the CIA between the different sources and Lancefield groups were assessed. We analyzed the association between high- and low-frequency CIA and VAG, emm genotype, sequence type/clonal complex, and AMR phenotype/genotype. Based on the mean (19.368 colony-forming units/100 cells) of 42 isolates, eight isolates had high-frequency CIA, whereas 34 had low-frequency CIA. We found an association between low-frequency CIA population and group G isolates, as well as a link between high-frequency CIA population and group C isolates. We also observed associations between low-frequency CIA population and oral/respiratory tract origin, ska, scpA, and lmb detection, and the AMR phenotype. Our observations suggest potential associations between high-/low-frequency CIA and the group, source, VAG, and AMR phenotypes.


Assuntos
Antibacterianos , Infecções Estreptocócicas , Streptococcus , Animais , Humanos , Antibacterianos/farmacologia , Infecções Estreptocócicas/microbiologia , Virulência/genética , Farmacorresistência Bacteriana/genética , Fenótipo
9.
Adv Sci (Weinh) ; 10(34): e2304461, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37867224

RESUMO

A current key challenge in 2D materials is the realization of emergent quantum phenomena in hetero structures via controlling the moiré potential created by the periodicity mismatch between adjacent layers, as highlighted by the discovery of superconductivity in twisted bilayer graphene. Generally, the lattice structure of the original host material remains unchanged even after the moiré superlattice is formed. However, much less attention is paid for the possibility that the moiré potential can also modify the original crystal structure itself. Here, it is demonstrated that octahedral MoTe2 which is unstable in bulk is stabilized in a commensurate MoTe2 /graphene hetero-bilayer due to the moiré potential created between the two layers. It is found that the reconstruction of electronic states via the moiré potential is responsible for this stabilization, as evidenced by the energy-gap opening at the Fermi level observed by angle-resolved photoemission and scanning tunneling spectroscopies. The present results provide a fresh approach to realize novel 2D quantum phases by utilizing the moiré potential.

10.
Cureus ; 15(7): e42640, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37644956

RESUMO

We describe the phenotypic and genotypic traits of Pasteurella multocida subsp. septica isolates from the dog/cat bite wounds of two patients in 2023. A 79-year-old man with diabetes mellitus and cerebral infarction who was bitten by a dog on his left hand developed deep inflammation under the tendon between his left fourth and fifth fingers. The patient's condition was resolved with antimicrobial treatment and surgical intervention. Another patient, a healthy 49-year-old woman who was bitten by a cat on her left hand, developed superficial inflammation of the left thumb and index finger. The patient's condition improved with antimicrobial treatment without surgical intervention. The isolates from the two patients had similar biochemical properties, and the antimicrobial susceptibility data for both isolates indicated erythromycin resistance. Genotypic analyses revealed clade 2 on the dendrogram of repetitive sequence-based fingerprinting, capsule serogroup cap genotype A, and hsf-1-nanH-pmHAS (virulence-associated genes). Our observations show that the two isolates have similar phenotypic and genotypic traits, regardless of differences in patient background, biting pets, wound inflammation, or the necessity of surgical intervention.

11.
J Vet Med Sci ; 85(8): 858-866, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37407445

RESUMO

The biotypic and genotypic features of Pasteurella canis isolated from dogs, cats, and humans were clarified by repetitive sequence-based fingerprinting and nucleotide sequences encoding trehalose-6-phosphate hydrolase (treC). Thirty P. canis and 48 P. multocida isolates were collected from dogs, cats, and humans to perform biotyping. The genotyping of P. canis by fingerprinting was followed by dendrogram construction. The whole-genome sequences (WGSs) were searched for the enzyme-coding nucleotide sequences around the main and adjacent loci constituting the operon. Full-length nucleotide sequences encoding the enzyme were determined using polymerase chain reaction and direct sequencing. Biotypic results were compared to the dendrogram and nucleotide sequence data. We observed a difference in trehalose fermentation with a positivity rate of 46.7%. Two (A-1/A-2) and three (B-1/B-2/B-3) clades were located on the dendrograms generated based on two repetitive sequence-based fingerprinting techniques, showing no association between trehalose fermentation and the clades. Based on the WGSs, two variants of the gene, namely, a 1,641 bp gene treC and a pseudogene (1,335 bp) of treC with its first 306 nucleotides deleted, were observed. Trehalose-positive isolates harbored treC, whereas trehalose-negative isolates lacked treC with or without the pseudogene. Our observations suggest biotypic and genotypic diversity among the P. canis isolates from animal and human hosts, with respect to trehalose fermentation and treC nucleotide sequences. This is the first report on the diversity of treC nucleotide sequences among these isolates.


Assuntos
Doenças do Cão , Infecções por Pasteurella , Pasteurella multocida , Humanos , Cães , Animais , Sequência de Bases , Trealose , Infecções por Pasteurella/veterinária , Fermentação , Pasteurella multocida/genética , Genótipo , Doenças do Cão/genética
12.
J Infect Chemother ; 29(9): 833-837, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37211085

RESUMO

OBJECTIVES: Clostridioides difficile infection (CDI) is a leading cause of antimicrobial-associated colitis and is a global clinical concern. Probiotics are considered a CDI-preventive measure; however, highly inconsistent data have been previously reported. Thus, we evaluated the CDI-preventive effect of prescribed probiotics in high-risk older patients receiving antibiotics. METHODS: Older patients (aged ≥65 years) admitted to the emergency department who received antibiotics between 2014 and 2017 were enrolled in this single-center retrospective cohort study. Propensity score-matched analysis was used to compare the CDI incidence in patients who took the prescribed probiotics within 2 days of receiving antibiotics for at least 7 days with those who did not. The rates of severe CDI and associated hospital mortality were also evaluated. RESULTS: Among 6148 eligible patients, 221 were included in the prescribed probiotic group. A propensity score-matched (221 matched pairs) well-balanced for patient characteristics was obtained. The incidence of primary nosocomial CDI did not differ significantly between the prescribed and non-prescribed probiotic groups (0% [0/221] vs. 1.0% [2/221], p = 0.156). Of the 6148 eligible patients, 0.5% (30/6148) developed CDI, with a severe CDI rate of 33.3% (10/30). Furthermore, no CDI-associated in-hospital mortality was observed in the study cohort. CONCLUSIONS: The evidence from this study does not support recommendations for the routine use of prescribed probiotics to prevent primary CDI in older patients receiving antibiotics in situations where the CDI is infrequent.


Assuntos
Infecções por Clostridium , Probióticos , Humanos , Idoso , Estudos Retrospectivos , Antibacterianos/efeitos adversos , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/tratamento farmacológico , Hospitalização , Probióticos/uso terapêutico
13.
Nano Lett ; 23(5): 1673-1679, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36849129

RESUMO

Boron-based two-dimensional (2D) materials are an excellent platform for nanoelectronics applications. Rhombohedral boron monosulfide (r-BS) is attracting particular attention because of its unique layered crystal structure suitable for exploring various functional properties originating in the 2D nature. However, studies to elucidate its fundamental electronic states have been largely limited because only tiny powdered crystals were available, hindering a precise investigation by spectroscopy such as angle-resolved photoemission spectroscopy (ARPES). Here we report the direct mapping of the band structure with a tiny (∼20 × 20 µm2) r-BS powder crystal by utilizing microfocused ARPES. We found that r-BS is a p-type semiconductor with a band gap of >0.5 eV characterized by the anisotropic in-plane effective mass. The present results demonstrate the high applicability of micro-ARPES to tiny powder crystals and widen an opportunity to access the yet-unexplored electronic states of various novel materials.

14.
J Orthop Res ; 41(1): 150-160, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35430743

RESUMO

Juvenile osteochondritis dissecans (JOCD) is an orthopedic joint disorder of children and adolescents that can lead to premature osteoarthritis. Thirteen patients (mean age: 12.3 years, 4 females), 15 JOCD-affected and five contralateral healthy knees, that had a baseline and a follow-up magnetic resonance imaging (MRI) (mean interval of 8.9 months) and were treated nonoperatively during this interval were included. Retrospectively, patients were assigned to operative or nonoperative groups based on their electronic medical records. Volumetric mean T2 * values were calculated within regions of interest (progeny lesion, interface, parent bone) and region matched control bone in healthy contralateral knees and condyles. The normalized percentage difference of T2 * between baseline and follow up MRI in nonoperative patients significantly increased in progeny lesion (-47.8%, p < 0.001), parent bone (-13.9%, p < 0.001), and interface (-32.3%, p = 0.011), whereas the differences in operative patients were nonsignificant and below 11%. In nonoperative patients, the progeny lesion (p < 0.001) and interface T2 * values (p = 0.012) were significantly higher than control bone T2 * at baseline, but not at follow-up (p = 0.219, p = 1.000, respectively). In operative patients, the progeny lesion and interface T2 * values remained significantly elevated compared to the control bone both at baseline (p < 0.001, p < 0.001) and follow-up (p < 0.001, p < 0.001), respectively. Clinical Significance: Longitudinal T2 * mapping differentiated nonhealing from healing JOCD lesions following initial nonoperative treatment, which may assist in prognosis and improve the ability of surgeons to make recommendations regarding operative versus nonoperative treatment.


Assuntos
Imageamento por Ressonância Magnética , Criança , Humanos , Adolescente , Projetos Piloto , Estudos Retrospectivos
15.
Jpn J Infect Dis ; 76(2): 135-144, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36450577

RESUMO

We assessed the biofilm production ability (BPA) of noninvasive Streptococcus dysgalactiae subsp. equisimilis (SDSE) in humans and companion animals and determined the relationship between bacterial populations with BPA and other host and microbiological features. Sixty-four isolates from companion animals and humans were collected along with host information. We measured BPA using crystal violet staining, in addition to emm typing, multilocus sequence typing, antimicrobial resistance (AMR) phenotyping/genotyping, and virulence-associated gene (VAG) detecting (prtF1-prtF2-lmb-cbp-sicG-srtp1-srtp2-brpA). Differences in the BPA of SDSE from different hosts and sources and different Lancefield groups were assessed. We analyzed the associations between populations with and without BPA (strong, moderate, weak, and no biofilm producers) and emm types, sequence types/clonal complexes (CCs), AMR phenotypes/genotypes, and VAG types. Seventeen, twenty-four, and twelve isolates were strong, moderate, and weak biofilm producers, respectively; eleven showed no BPA. There was a difference in the distribution of populations with BPA between human and animal origins and between isolates of groups G and C. We found an association between populations with BPA and the eye and ear source (vs. the pus and skin source). A relationship was observed between the populations with BPA and CC127 (vs. CC17). We observed no association between the populations with BPA and AMR phenotype/genotype. There was an association between the distribution of populations with BPA and srtp1 expression. Our observations suggest potential associations between populations with BPA and the host species, Lancefield group, source, CC, and VAG type.


Assuntos
Infecções Estreptocócicas , Animais , Humanos , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Virulência/genética , Streptococcus , Tipagem de Sequências Multilocus
16.
Ann Lab Med ; 43(3): 263-272, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36544338

RESUMO

Background: Comparative analysis of virulence factors (VFs) between Pasteurella canis and Pasteurella multocida are lacking, although both cause zoonotic infections. We determined the virulence-associated genome sequence characteristics of P. canis and assessed the toxin gene prevalence unique to P. canis among clinical isolates of P. canis and P. multocida. Methods: We selected 10 P. canis and 16 P. multocida whole-genome sequences (WGSs) from the National Center for Biotechnology database. The VFanalyzer tool was used to estimate P. canis-characteristic VFs. Amino acid sequences of VFs were compared with multiple-aligned sequences. The genome structure containing P. canis-characteristic and adjacent loci was compared to the corresponding P. multocida genome structure. After designing primer sequences and assessing their accuracy, we examined the gene prevalence of the P. canis-characteristic VFs using PCR among clinical isolates of P. multocida and P. canis. Results: Using VFanalyzer, we found virulence-associated cytolethal distending toxin (cdt)A-cdtB-cdtC loci common to all P. canis WGSs that were not found in P. multocida WGSs. Similarities in the multiple alignments of CdtA-CdtB-CdtC amino acid sequences were found among the 10 P. canis WGSs. Shared or similar loci around cdtA-cdtB-cdtC were identified between the P. canis and P. multocida genome structures. The PCR-based cdtA-cdtB-cdtC prevalence differed for P. canis and P. multocida clinical isolates. Conclusions: P. canis-specific cdtA-cdtB-cdtC prevalence was identified among clinical isolates. These three loci may be unique toxin genes and promising targets for the rapid identification of P. canis in clinical settings.


Assuntos
Pasteurella multocida , Humanos , Animais , Pasteurella multocida/genética , Animais de Estimação , Virulência/genética , Prevalência
17.
Oncogene ; 42(5): 364-373, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36522487

RESUMO

Non-coding RNAs have an integral regulatory role in numerous functions related to lung cancer development. Here, we report identification of a novel lncRNA, termed TP53-inhibiting lncRNA (TILR), which was found to function as a constitutive negative regulator of p53 expression, including activation of downstream genes such as p21 and MDM2, and induction of apoptosis. A proteomic search for TILR-associated proteins revealed an association with PCBP2, while the mid-portion of TILR was found to be required for both PCBP2 and p53 mRNA binding. In addition, depletion of PCBP2 resulted in phenocopied effects of TILR silencing. TILR was also shown to suppress p53 expression in a post-transcriptional manner, as well as via a positive feedback loop involving p53 and Fanconi anemia pathway genes. Taken together, the present findings clearly demonstrate that TILR constitutively inhibits p53 expression in cooperation with PCBP2, thus maintaining p53 transcriptional activity at a level sufficiently low for avoidance of spurious apoptosis induction.


Assuntos
Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Apoptose/genética , Proliferação de Células/genética , Neoplasias Pulmonares/genética , Proteômica , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Phys Rev Lett ; 129(20): 206402, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36461993

RESUMO

Kagome metals AV_{3}Sb_{5} (A=K, Rb, and Cs) exhibit a characteristic superconducting ground state coexisting with a charge density wave (CDW), whereas the mechanisms of the superconductivity and CDW have yet to be clarified. Here we report a systematic angle-resolved photoemission spectroscopy (ARPES) study of Cs(V_{1-x}Nb_{x})_{3}Sb_{5} as a function of Nb content x, where isovalent Nb substitution causes an enhancement of superconducting transition temperature (T_{c}) and the reduction of CDW temperature (T_{CDW}). We found that the Nb substitution shifts the Sb-derived electron band at the Γ point downward and simultaneously moves the V-derived band around the M point upward to lift up the saddle point (SP) away from the Fermi level, leading to the reduction of the CDW-gap magnitude and T_{CDW}. This indicates a primary role of the SP density of states to stabilize the CDW. The present result also suggests that the enhancement of superconductivity by Nb substitution is caused by the cooperation between the expansion of the Sb-derived electron pocket and the recovery of the V-derived density of states at the Fermi level.

19.
Front Cardiovasc Med ; 9: 1007213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386385

RESUMO

Infectious aortic aneurysm (IAA) can be a rare but potentially fatal sequela of infectious inflammatory disease of the aortic wall with a high incidence of rupture. The definitive diagnosis is based on vascular imaging of the aneurysm using contrast-enhanced computed tomography (CE-CT) and identification of the causative microorganism from positive blood cultures (BCs). However, IAA remains extremely difficult to diagnose and treat in patients with prior antimicrobial treatment or with renal dysfunction. Here we describe a case of an 85-year-old woman with IAA caused by Arthrobacter russicus presenting with abdominal pain and fever that was initially diagnosed as a presumptive urinary tract infection and treated with empiric antimicrobial therapy. However, persistent abdominal pain with increased serological inflammation necessitated further evaluation. Unenhanced multimodality imaging considering the renal dysfunction revealed infectious aortitis of the infrarenal abdominal aorta, together with the initial culture results, leading to the tentative diagnosis of Klebsiella pneumoniae aortitis. Thereafter, serial monitoring with unenhanced magnetic resonance angiography (MRA) using thin-slab maximum intensity projection (TS-MIP) revealed acute aortic expansion strongly suggestive of a pseudoaneurysm that was successfully treated with early surgical repair under adequate infection control. Despite negative Gram staining and tissue culture results for the excised aortic wall, a definitive diagnosis of IAA secondary to A. russicus rather than K. pneumoniae was finally made by confirming the histologic findings consistent with IAA and the identification of A. russicus 16S rRNA on the resected aortic wall. The patient also developed a vascular graft infection during the postoperative course that required long-term systemic antimicrobial therapy. This case highlights the value of unenhanced MRA in the early detection of IAA in patients with renal dysfunction and the importance of a molecular diagnosis for identifying the causative microorganism in cases of culture- or tissue-negative IAA.

20.
Opt Express ; 30(15): 28182-28189, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236971

RESUMO

We surveyed the longitudinal-mode linewidth of five homemade mode-locked Yb:fiber lasers by taking the beat note with a Hz-level narrow-linewidth CW laser. We systematically varied the resolution bandwidth of the spectrum analyzer and found that the linewidth can be as narrow as 200 Hz, which surpassed the records for free-running mode-locked lasers in the literature to our best knowledge. Based on the survey, we propose that making the cavity long and simple is a good working hypothesis for narrowing the linewidth and provide practical techniques to reduce the environmental fluctuations.

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