Establishment of conditional vectors for hairpin siRNA knockdowns

Small interference RNA (siRNA) is an emerging methodology in reverse genetics. Here we report the development of a new tetracycline-inducible vector-based siRNA system, which uses a tetracycline-responsive derivative of the U6 promoter and the tetracycline repressor for conditional in vivo transcription of short hairpin RNA. This method prevents potential lethality immediately after transfection of a vector when the targeted gene is indispensable, or the phenotype of the knockdown is lethal or results in a growth abnormality. We show that the controlled knockdown of DNA methyltransferase 1 (DNMT1) in human cancer resulted in growth arrest. Removal of the inducer, doxycycline, from treated cells led to re-expression of the targeted gene. Thus the method allows for a highly controlled approach to gene knockdown

Mean platelet volume and lymphocyte-to-monocyte ratio are associated with shorter progression-free survival in EGFR-mutant lung adenocarcinoma treated by EGFR tyrosine kinase inhibitor.

BACKGROUND:A growing body of evidence supports the role of platelets in cancer metastasis, escape from immune surveillance, and angiogenesis. Mean platelet volume (MPV), which reflects platelet turnover, is reported routinely as part of automated complete blood count. Accumulating evidence suggests that MPV is a useful biomarker in several diseases including cancer. However, its role in cancer patients receiving molecular targeted therapy has not been described in the literature. MATERIALS AND METHODS:We retrospectively analysed the prognostic impact of MPV in advanced or recurrent EGFR mutant lung adenocarcinoma treated with EGFR tyrosine kinase inhibitors (EGFR-TKIs). Lymphocyte-to-monocyte ratio (LMR) has been previously reported to be a poor prognostic factor in EGFR mutant non-small cell lung cancer and was also included as a covariate. RESULTS:Using the previously described Cutoff Finder algorithm, the cut-off points for MPV and LMR that best predicted progression free survival (PFS) of EGFR-TKI were determined as 10.3 and 2.8, respectively. The median PFS was 14.7 and 8.2 months in MPV low and high groups (p = 0.013, log-rank test). The median PFS was 13.5 and 6.2 months in LMR high and low groups (p < 0.001, log-rank test). MPV and LMR were independently distributed (chi square test) and the multivariate analysis using Cox's proportional hazards regression model revealed that high MPV, low LMR, and pleural effusion were significant predictors for shorter PFS. CONCLUSION:MPV and LMR, measured as part of routine complete blood count, can be utilized to predict the outcome of EGFR-TKI therapy with no additional costs. Our results suggest a mechanism of EGFR-TKI resistance which is associated with the functional status of the platelets

Successful Treatment of Mediastinal Unicentric Castleman’s Disease Using Video-Assisted Thoracoscopic Surgery with Preoperative Embolization

Unicentric Castleman’s disease is a rare, benign lymphoproliferative disorder that is curable with surgical resection. However, significant bleeding often occurs during surgery because of tumor hypervascularity. We herein present a case of hyaline-vascular-type mediastinal unicentric Castleman’s disease, successfully resected using video-assisted thoracoscopic surgery with preoperative embolization. In the present case, tumor hypervascularity and feeding vessels were revealed by computed tomography (CT), which led us to perform preoperative angiography and embolization to the tumor feeding arteries to reduce intraoperative bleeding. Castleman’s disease should be considered in the differential diagnosis of hypervascular mediastinal tumors. Tumor vascularity should be assessed prior to surgery, and preoperative embolization should be considered

Cerebral Arterial Air Embolism after Diagnostic Flexible Fiberoptic Bronchoscopy: A Case Report and Review of the Literature

Cerebral arterial air embolism (CAAE) is an extremely rare complication of diagnostic flexible fiberoptic bronchoscopy, reported to occur once about every 103978 examinations. In all the eight cases of CAAE reported previously, the patients had undergone transbronchial lung biopsy (TBLB) or transbronchial needle aspiration (TBNA) prior to the onset of CAAE. Herein, we describe the case of a 77-year-old patient with double primary lung cancer who developed CAAE after bronchial curette cytology, which is considered to be less invasive than TBLB or TBNA. The patient was treated with supplemental oxygen, but paresis of the left upper arm and left spatial neglect remained. This is the first report of CAAE occurring after bronchial curettage during diagnostic flexible fiberoptic bronchoscopy

Successful treatment of pulmonary injury after nitrogen oxide exposure with corticosteroid therapy: A case report and review of the literature

Nitrogen oxides are representative chemicals of occupational and environmental exposure, which can lead to fatal pulmonary injury. These oxides are also known to cause delayed occurrence of bronchiolitis obliterans (BO). Herein, we report a case of nitrogen oxide-induced lung injury. A 50-year-old man developed pulmonary edema after nitric acid exposure. Hypoxemia and respiratory failure were immediately improved after introduction of corticosteroid pulse therapy with supplemental oxygen. This was followed by administration of oral prednisolone, and delayed BO did not develop. This case supports the therapeutic efficacy of corticosteroids against pulmonary injury and late-onset BO after nitrogen oxide exposure. Key clinical message: Prolonged oral prednisolone might be a potential therapy to prevent delayed onset of bronchiolitis obliterans after nitric acid exposure

Risk factors and interventions for developing recurrent pneumonia in older adults

Background Pneumonia is common among older adults and often recurrent. Several studies have been conducted on the risk factors for pneumonia; however, little is known about the risk factors for recurrent pneumonia. This study aimed to identify the risk factors for developing recurrent pneumonia among older adults and to investigate methods of prevention. Methods We analysed the data of 256 patients aged 75 years or older who were admitted for pneumonia between June 2014 and May 2017. Moreover, we reviewed the medical records for the subsequent 3 years and defined the readmission caused by pneumonia as recurrent pneumonia. Risk factors for recurrent pneumonia were analysed using multivariable logistic regression analysis. Differences in the recurrence rate based on the types and use of hypnotics were also evaluated. Results Of the 256 patients, 90 (35.2%) experienced recurrent pneumonia. A low body mass index (OR: 0.91; 95% CI: 0.83‒0.99), history of pneumonia (OR: 2.71; 95% CI: 1.23‒6.13), lung disease as a comorbidity (OR: 4.73; 95% CI: 2.13‒11.60), taking hypnotics (OR: 2.16; 95% CI: 1.18‒4.01) and taking histamine-1 receptor antagonist (H1RA) (OR: 2.38; 95% CI: 1.07‒5.39) were risk factors. Patients taking benzodiazepine as hypnotics were more likely to experience recurrent pneumonia than patients not taking hypnotics (OR: 2.29; 95% CI: 1.25–4.18). Conclusion We identified several risk factors for recurrent pneumonia. Among them, restricting the use of H1RA and hypnotics, in particular benzodiazepines, may be useful in preventing the recurrence of pneumonia in adults aged 75 years or older