Measurement of the Noise Spectrum Using a Multiple-Pulse Sequence

A method is proposed for obtaining the spectrum for noise that causes the phase decoherence of a qubit directly from experimentally available data. The method is based on a simple relationship between the spectrum and the coherence time of the qubit in the presence of a pi-pulse sequence. The relationship is found to hold for every system of a qubit interacting with the classical-noise, bosonic, and spin baths.Comment: 8 pages (4 pages + 4 pages Supplemental material), 1 figur

ERG3-encoding sterol C5,6-DESATURASE in Candida albicans Is required for virulence in an enterically infected invasive candidiasis mouse model

Gastrointestinal colonization by Candida species is considered the main source of candidemia. The ERG3 gene in Candida albicans encodes a sterol C5,6-desaturase, which is essential for ergosterol biosynthesis. Although ERG3 inactivation shows reduced virulence in mouse models of disseminated candidiasis, the role of ERG3 in intestinal infections is unknown. Here, we infected mice with the C. albicans strains CAE3DU3 and CAF2-1, containing mutant and wild-type ERG3, respectively, and studied gut infection and colonization by these strains. We found that the CAE3DU3 strain showed reduced colonization, pathogenesis, damage to gut mucosa, and chemokine production in the mouse model of invasive candidiasis. Additionally, mice inoculated with CAE3DU3 showed lower mortality than mice inoculated with CAF2-1 (p < 0.0001). Chemokines were less induced in the gut inoculated with CAE3DU3 than in the gut inoculated with CAF2-1. Histopathologically, ]although the wild-type gene was associated with a higher pathogenicity and invasion of the gut mucosa and liver tissues causing remarkable tissue necrosis, the erg3/erg3 mutant was associated with a higher accumulation of cells and lower damage to surrounding tissues than wild-type ERG3. These results establish that the ergosterol biosynthetic pathway may be associated with C. albicans gut colonization and subsequent dissemination

The SNP rs6508974 in AXL is a functional polymorphism and a promising biomarker for gefitinib treatment

Somatic mutations in epidermal growth factor receptor (EGFR) found in lung adenocarcinomas are used as biomarkers for the treatment with EGFR-tyrosine kinase inhibitors, including gefitinib. The bypass tracks with amplification of AXL is one of the mechanisms underlying the resistance to gefitinib. We, therefore, carried out a candidate gene approach method to identify AXL polymorphisms associated with the effectiveness of gefitinib. EGFR mutations were first dentified by mutantenriched PCR-restriction fragment length polymorphism (RFLP), and then 2 tag single nucleotide olymorphisms (SNPs) of AXL were examined by PCR-RFLP in 62 Japanese patients with advanced lung adenocarcinoma and treated with gefitinib in two general hospitals in Nagasaki. Subsequently, the association of EFGR mutations and the AXL polymorphism with the effectiveness of gefitinib was examined in these patients. We next examined the effect of the AXL polymorphism on the expression and function of this gene. It is worthy of note that EGFR mutations and the AXL polymorphism rs6508974 independently contributed to the effectiveness of gefitinib, and the polymorphism was proved to be a possible biomarker for selecting non-responders and responders to gefitinib treatment even in the absence of EGFR mutations. Furthermore, this SNP increased the transcriptional activity of the AXL transcript variant 3, one of the three AXL transcript variants, which to some extent increased the epithelial-mesenchymal transition in cancer cells. Taken together, AXL is one of the genes that determine the effectiveness of gefitinib and a biomarker for selecting non-responders and responders among lung adenocarcinoma patients with no EGFR mutations, suggesting that rs6508974 in AXL might be a functional SNP in lung denocarcinoma

Clinical and experimental phenotype of azole-resistant Aspergillus fumigatus with a HapE splice site mutation: a case report

Background: The recent increase in cases of azole-resistant Aspergillus fumigatus (ARAf) infections is a major clinical concern owing to its treatment limitations. Patient-derived ARAf occurs after prolonged azole treatment in patients with aspergillosis and involves various cyp51A point mutations or non-cyp51A mutations. The prognosis of patients with chronic pulmonary aspergillosis (CPA) with patient-derived ARAf infection remains unclear. In this study, we reported the case of a patient with ARAf due to HapE mutation, as well as the virulence of the isolate.Case presentation: A 37-year-old male was presented with productive cough and low-grade fever. The patient was diagnosed with CPA based on the chronic course, presence of a fungus ball in the upper left lobe on chest computed tomography (CT), positivity for Aspergillus-precipitating antibody and denial of other diseases. The patient underwent left upper lobe and left S6 segment resection surgery because of repeated haemoptysis during voriconazole (VRC) treatment. The patient was postoperatively treated with VRC for 6 months. Since then, the patient was followed up without antifungal treatment but relapsed 4 years later, and VRC treatment was reinitiated. Although an azole-resistant isolate was isolated after VRC treatment, the patient did not show any disease progression in either respiratory symptoms or radiological findings. The ARAf isolated from this patient showed slow growth, decreased biomass and biofilm formation in vitro, and decreased virulence in the Galleria mellonella infection model compared with its parental strain. These phenotypes could be caused by the HapE splice site mutation.Conclusions: This is the first to report a case demonstrating the clinical manifestation of a CPA patient infected with ARAf with a HapE splice site mutation, which was consistent with the in vitro and in vivo attenuated virulence of the ARAf isolate. These results imply that not all the ARAf infections in immunocompetent patients require antifungal treatment. Further studies on the virulence of non-cyp51A mutations in ARAf are warranted

Serum Cytokines Usefulness for Understanding the Pathology in Allergic Bronchopulmonary Aspergillosis and Chronic Pulmonary Aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) and chronic pulmonary aspergillosis (CPA) are important fungal infections caused by Aspergillus species. An overlap of ABPA and CPA has been reported; therefore, it is critical to determine whether the main pathology is ABPA or CPA and whether antifungals are required. In this study, we investigated whether the serum cytokine profile is useful for understanding the pathology and for differentiating between these diseases. We compared the various serum cytokine levels among healthy subjects and patients diagnosed with asthma, ABPA, or CPA at Nagasaki University Hospital between January 2003 and December 2018. In total, 14 healthy subjects, 19 patients with asthma, 11 with ABPA, and 10 with CPA were enrolled. Interleukin (IL) -5 levels were significantly higher in patients with ABPA than in those with CPA, and IL-33 and tumor necrosis factor (TNF) levels were significantly higher in patients with CPA than in those with asthma (p < 0.05, Dunn’s multiple comparison test). The sensitivity and specificity of the IL-10/IL-5 ratio (cutoff index 2.47) for diagnosing CPA were 70% and 100%, respectively. The serum cytokine profile is useful in understanding the pathology of ABPA and CPA, and the IL-10/IL-5 ratio may be a novel supplemental biomarker for indicating the pathology of CPA

Virulence assessment of six major pathogenic Candida species in the mouse model of invasive candidiasis caused by fungal translocation

Gastrointestinal colonization has been considered as the primary source of candidaemia; however, few established mouse models are available that mimic this infection route. We therefore developed a reproducible mouse model of invasive candidiasis initiated by fungal translocation and compared the virulence of six major pathogenic Candida species. The mice were fed a low-protein diet and then inoculated intragastrically with Candida cells. Oral antibiotics and cyclophosphamide were then administered to facilitate colonization and subsequent dissemination of Candida cells. Mice infected with Candida albicans and Candida tropicalis exhibited higher mortality than mice infected with the other four species. Among the less virulent species, stool titres of Candida glabrata and Candida parapsilosis were higher than those of Candida krusei and Candida guilliermondii. The fungal burdens of C. parapsilosis and C. krusei in the livers and kidneys were significantly greater than those of C. guilliermondii. Histopathologically, C. albicans demonstrated the highest pathogenicity to invade into gut mucosa and liver tissues causing marked necrosis. Overall, this model allowed analysis of the virulence traits of Candida strains in individual mice including colonization in the gut, penetration into intestinal mucosa, invasion into blood vessels, and the subsequent dissemination leading to lethal infections

Infectious Pneumonia and Lower Airway Microorganisms in Patients with Rheumatoid Arthritis

The relationship between microorganisms present in the lower respiratory tract and the subsequent incidence of pneumonia in patients with rheumatoid arthritis is unclear. A retrospective cohort study was designed to include a total of 121 patients with rheumatoid arthritis who underwent bronchoscopy at three hospitals between January 2008 and December 2017. Data on patient characteristics, microorganisms detected by bronchoscopy, and subsequent incidences of pneumonia were obtained from electronic medical records. Patients were divided into groups based on the microorganisms isolated from the lower respiratory tract. The cumulative incidence of pneumonia was assessed using the Kaplan–Meier method, and decision tree analysis was performed to analyze the relation between the presence of microorganisms and the occurrence of pneumonia. The most frequently isolated microbes were Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae. Patients whose samples tested negative for bacteria or positive for normal oral flora were included in the control group. The rate of the subsequent incidence of pneumonia was higher in the P. aeruginosa group than in the control group (p = 0.026), and decision tree analysis suggested that P. aeruginosa and patient performance status were two important factors for predicting the incidence of pneumonia. In patients with rheumatoid arthritis, the presence of P. aeruginosa in the lower respiratory tract was associated with the subsequent incidence of pneumonia

Influenza A (H3N2) infection followed by anti-signal recognition particle antibody-positive necrotizing myopathy: A case report

A 60-year-old Japanese woman presented with subacute progressive muscle pain and weakness in her proximal extremities. She was diagnosed with influenza A (H3N2) infection a week before the onset of muscle pain. At the time of admission, she exhibited weakness in the proximal muscles of the upper and lower limbs, elevated serum liver enzymes and creatinine kinase, and myoglobinuria. She did not manifest renal failure and cardiac abnormalities, indicating myocarditis.Electromyography revealed myogenic changes, and magnetic resonance imaging of the upper limb showed abnormal signal intensities in the muscles, suggestive of myopathy. Muscle biopsy of the biceps revealed numerous necrotic regeneration fibers and mild inflammatory cell infiltration, suggesting immune-mediated necrotizing myopathy (IMNM). Necrotized muscle cells were positive for human influenza A (H3N2). Autoantibody analysis showed the presence of antibodies against the signal recognition particle (SRP), and the patient was diagnosed with anti-SRP-associated IMNM. She was resistant to intravenous methylprednisolone pulse therapy but recovered after administration of oral systemic corticosteroids and immunoglobulins. We speculate that the influenza A (H3N2)infection might have triggered her IMNM. Thus, IMNM should be considered as a differential diagnosis in patients with proximal muscle weakness that persists after viral infections

多剤耐性カンジダおよび細菌に対するカスポファンギンの新たな抗微生物活性

長崎大学学位論文 [学位記番号]博（医歯薬）甲第1326号 [学位授与年月日]令和3年3月22