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41.
BackgroundDealing with chemotherapy-related cardiac dysfunction (CTRCD) remains a significant problem complicated by the difficulty in early detection of cardiotoxicity. Electrocardiogram (ECG) is expected to be the most realistic methodology due to lower cost-performance and non-invasiveness. We investigated the long-term visual fluctuations in the ECG waveforms in patients with chronic doxorubicin (DOX)-induced cardiotoxicity to identify ECG indices for the early detection of cardiotoxicity.MethodsWe conducted a retrospective case series study by reviewing the medical records of 470 consecutive patients with malignant lymphoma who were treated with DOX at our institute between January 2010 and December 2017. Of them, 23 (4.9%) patients developed left ventricular dysfunction and were diagnosed with CTRCD using echocardiography. We assessed the ECG indices on 12-lead ECG recordings before and after treatment in 15 patients; eight patients were excluded due to conduction disturbances or atrial fibrillation.ResultsCTRCD was detected at a median of 475 (interquartile range, IQR: 341–1333) days after initiating chemotherapy. The evaluation of ECG indices preceding CTRCD development was performed 93 (IQR: 52–232) days before the detection of CTRCD. In the stage of CTRCD, the most significant ECG change was T-wave flattening in leads V3–V6 (12 patients, 80%). Additionally, QTa prolongation was observed in leads I and aVL (n = 10, 66%), leads II, III, and aVF (n = 9, 60%), and leads V3–V6 (n = 10, 73%). These ECG changes were not observed before the treatment but were detected mildly in the pre-CTRCD stage, which subsequently worsened in the CTRCD stage.ConclusionsThis study indicated that T-wave changes and QTa prolongation may be useful as an early indicator before the onset of CTRCD in patients with DOX-induced cardiotoxicity.  相似文献   
42.
Journal of Gastroenterology - Polymorphisms in the nucleotide diphosphate-linked moiety X-type motif 15 (NUDT15) gene are associated with thiopurine-induced leukopenia in patients with inflammatory...  相似文献   
43.
Purpose

Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO2) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF.

Methods

We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO2 and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation.

Results

Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO2 during sleep and total sleep time spent with SpO2?<?90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern.

Conclusion

We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

  相似文献   
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45.
Tanaka S  Tanaka H  Abe S 《Chest》2003,124(5):1768-1773
BACKGROUND: The circadian variation in urinary leukotriene E(4) (LTE(4)) excretion with a morning acrophase has recently been reported in nocturnal asthma (NA); however, the effects of inhaled corticosteroids (ICS) on this circadian rhythmicity of leukotriene (LT) in patients with NA are controversial. METHODS: We first measured peak expiratory flow (PEF), urinary LTE(4), 11-dehydro-thromboxane B(2) (TXB(2)), and creatinine levels six times every 4 h for 24 h in two groups: patients with mild-to-moderate, steroid-naive NA (n = 10, group A), and patients with severe NA treated with high-dose ICS (n = 10, group B). Next, group A patients received 2 weeks of treatment with 800 microg/d of inhaled fluticasone propionate (FP), and we compared the measured parameters before and after treatment. RESULTS: In group A, a circadian rhythm in urinary LTE(4) with peak levels at approximately 4 AM associated with reduced PEF was observed. Group B had suppression of urinary LTE(4) excretion and had no circadian rhythmicity, as seen in group A, despite a dip in PEF at 4 AM. A high dose of FP in group A significantly (p < 0.05) reduced LTE(4) levels and abolished the circadian rhythm, as well as improving PEF. We found no significant difference in the circadian rhythm of urinary 11-dehydro-TXB(2) between groups A and B, and high-dose FP partially decreased urinary 11-dehydro-TXB(2) levels but not significantly. CONCLUSIONS: A high-dose of ICS reduced urinary LTE(4) levels and abolished their circadian variation in patients with asthma, suggesting that LT might contribute to the mechanism of NA.  相似文献   
46.
The antimicrobial susceptibility test was necessary for the eradication therapy of Helicobacter pylori infections. This is because, clarithromycin resistant strains has became an increasing problem. In this study, we used the antimicrobial susceptibility test which was compare with the agar gradient method, Etest, and broth microdilution method (dry plate) with 4 antimicrobial agents. The results strongly suggested that broth microdilution method was the best method in order to test the antimicrobial susceptibility of H. pylori. On the other hand, 393 H. pylori stains isolated during 1994-1998 from clinical patients were tested for antimicrobial susceptibility test to amoxicillin, clarithromycin, metronidazole, and minomycin. There were no resistant strains to amoxicillin and minomycin. But clarithromycin and Metronidazole resistant strains were recognized in 85 (22.0%) and 36 (21.7%) strains.  相似文献   
47.
48.
Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway.  相似文献   
49.
T helper 17 (Th17) cells that produce interleukin (IL)-17A and IL-17F have been found to participate in the development of bronchial asthma and bleomycin-induced pulmonary fibrosis. However, whether they play a causative role in the airway remodeling observed in these respiratory diseases remains unclear. Because fibrocytes are involved in tissue repair and fibrosis and are presumably precursors of lung fibroblasts and myofibroblasts, we examined the effects of IL-17A/F on fibrocyte functions. Both IL-17A and IL-17F enhanced fibrocytes’ α-smooth muscle actin expression. Priming fibrocytes with IL-17A enhanced their CD40-mediated IL-6 production, whereas IL-17F-priming increased the CD40-mediated mRNA expression of collagen I, vascular endothelial growth factor, and angiogenin. CD4+ T cells co-cultured with fibrocytes produced IL-17A, which was inhibited by blocking CD40 and CD40 ligand interactions. These findings suggest that cooperative interactions between fibrocytes and Th17 cells play an important role via CD40- and IL-17A/F-mediated signaling for collagen and proangiogenic factor production, which may lead to the extracellular matrix deposition and neovascularization seen in airway remodeling.  相似文献   
50.
Annals of Nuclear Medicine - Albumin–globulin ratio (AGR), which is calculated by dividing serum albumin by serum globulin, is considered as a cancer-related inflammation biomarker. Although...  相似文献   
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