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61.
ObjectivesSialolipoma has been classified as a benign soft tissue lesion in the 2017 World Health Organization classification of head and neck tumors. To our knowledge, only one case of laryngeal sialolipoma has been reported in the English literature. We conducted a retrospective study to identify clinical characteristics of supraglottic sialolipoma-like lesion and differentiate it from other supraglottic subepithelial masses.MethodsMedical records of 16 patients with supraglottic subepithelial benign mass lesions who underwent histological evaluation between 2003 and 2019 were retrospectively analyzed. Sialolipoma-like lesion was defined as a local finding of a well-circumscribed gross mass with pathological presence of salivary gland-like parenchymal lobules with evenly interspersed adipose tissue.ResultsEight patients showed histological positivity for sialolipoma-like lesion, 3 for amyloidosis, 2 for hemangioma, and 1 each for cyst, lymphoid hyperplasia, and chondrometaplasia. Sialolipoma-like lesion tended to be predominant among men; those affected had a mean age of 52.8 (range, 39–74) years. By contrast, among patients with amyloidosis, the ratio of men to women was 1:2 (100% vs. 33%; p = 0.055). Fiberscopic examination of all patients with sialolipoma-like lesions identified well-circumscribed, yellowish masses, closely resembling local amyloidosis findings. Sialolipoma-like lesion was associated with a significantly higher body-mass index (BMI; 27.4 ± 2.8 kg/m2) than amyloidosis (21.6 ± 1.4 kg/m2; p = 0.014). The transoral approach was used for lesion resection in all patients with sialolipoma-like lesion. No patient experienced postoperative recurrence.ConclusionLaryngeal sialolipoma-like lesion might be more prevalent than was previously reported, and histological examination is important to differentiate it from amyloidosis. Supraglottic sialolipoma-like lesion must be differentially diagnosed in patients with high BMI presenting with well-circumscribed, yellowish supraglottic masses.  相似文献   
62.
The mechanism of immune defense against pathogens in the lung, has so far been poorly understood. Here, we show that human type II alveolar epithelial cells play a key role in defense via interactions between B7 homolog (B7h), also known as ICOS ligand, and its receptor ICOS expressed on activated T cells. The A549 alveolar type II cell line abundantly expresses B7-H2, CD40 and B7-1, but not B7-2 or hGL50. TNF-alpha significantly induced B7-H2 and CD40 expression by A549 cells, but had no effect on B7-1 or B7-2 expression. TNF-alpha-deficient mice exhibited low B7-H2 expression on alveolar epithelial cells in comparison with wild-type mice. Co-culture of TNF-alpha pre-stimulated A549 cells with CD4+ T cells promoted CD154 expression, CD4+ T cell proliferation and cytokine production, especially IFN-gamma. Monocyte-derived TNF-alpha in combination with IFN-gamma and LPS markedly induced B7-H2 expression in A549 cells. This study thus identifies a unique costimulatory pathway via alveolar epithelial type II cells that preferentially affects T helper cell function, implying that alveolar epithelial type II cells play a crucial role in innate immunity in the lung by regulating IFN-gamma-synthesis via B7-H2/ICOS interactions.  相似文献   
63.
A healthy man in his 30s was working on the balustrade of stairs on the second floor. He suddenly fell downstairs without saying anything. On emergency hospitalization, chest echogram showed left hemothorax. Cardiac echogram showed a floating mass from the mitral valve in the left ventricle and severe mitral regurgitation. Surgery for hemothorax and pulmonary contusion was immediately undertaken. However, bleeding from pulmonary contusion could not be controlled and he underwent cardiopulmonary arrest. Autopsy showed a white, elastic, pendulous mass in the left atrium and a white mass in the lower lobe of the left lung. Tumor histology showed a reticular pattern, Schiller-Duval bodies, eosinophilic hyaline globules, and positive staining for α-fetoprotein. We diagnosed primary lung yolk sac tumor with metastatic intracardiac yolk sac tumor, a rare and highly malignant germ cell tumor. It usually arises in the ovaries and testes, and intracardiac yolk sac tumor is rare. Intracavitary tumors induce obstruction of inflow into and outflow from the ventricular cavity. The most common clinical presentation is dyspnea and syncope. In the present case, metastatic cardiac yolk sac tumor might have disturbed cardiac outflow and affected hemodynamics, probably causing syncope. Unfortunately, he was in a high place at that time and fell to receive pulmonary contusion that led to death. Autopsy may sometimes reveal latent diseases which might be related to the cause of death. We should perform autopsy thoroughly to diagnose not only the cause of death but also the factors leading to death.  相似文献   
64.
A man aged in his thirties was found dead in his room, wearing a gas mask connected with two plastic bags. An empty canister of Air Duster was in one of the plastic bags. Toxicological analysis by gas chromatography (GC)-mass spectrometry and GC-flame ionization detection revealed the presence of 1,1-difluoroethane (HFC-152a), which is a component of the Air Duster aerosol. Quantitative analysis showed that the concentration of 1,1-difluoroethane in his heart blood was as high as 546 μg/ml. The cause of death was diagnosed as acute poisoning by 1,1-difluoroethane. It was supposed that he abused the Air Duster product to obtain euphoria and inhaled 1,1-difluoroethane at excessive concentrations with the peculiar tight-fitting gas inhalation device, resulting in his death.  相似文献   
65.
Objectives:To determine the optimal scan delay corresponding to individual hemodynamic status for pancreatic parenchymal phase in dynamic contrast-enhanced CT of the abdomen.Methods:One hundred and fourteen patients were included in this retrospective study (69 males and 45 females; mean age, 67.9 ± 12.1 years; range, 39–87 years). These patients underwent abdominal dynamic contrast-enhanced CT between November 2019 and May 2020. We calculated and recorded the time from contrast material injection to the bolus-tracking trigger of 100 Hounsfield unit (HU) at the abdominal aorta (s) (TimeTRIG) and scan delay from the bolus-tracking trigger to the initiation of pancreatic parenchymal phase scanning (s) (TimeSD). The scan delay ratio (SDR) was defined by dividing the TimeSD by TimeTRIG. Non-linear regression analysis was conducted to assess the association between CT number of the pancreas and SDR and to reveal the optimal SDR, which was ≥120 HU in pancreatic parenchyma.Results:The non-linear regression analysis showed a significant association between CT number of the pancreas and the SDR (p < 0.001). The mean TimeTRIG and TimeSD were 16.1 s and 16.8 s, respectively. The SDR to peak enhancement of the pancreas (123.5 HU) was 1.00. An SDR between 0.89 and 1.18 shows an appropriate enhancement of the pancreas (≥120 HU).Conclusion:The CT number of the pancreas peaked at an SDR of 1.00, which means TimeSD should be approximately the same as TimeTRIG to obtain appropriate pancreatic parenchymal phase images in dynamic contrast-enhanced CT with bolus-tracking method.Advances in knowledge:The hemodynamic state is different in each patient; therefore, scan delay from the bolus-tracking trigger should also vary based on the time from contrast material injection to the bolus-tracking trigger. This is necessary to obtain appropriate late hepatic arterial or pancreatic parenchymal phase images in dynamic contrast-enhanced CT of the abdomen.  相似文献   
66.
International Urology and Nephrology - Radical prostatectomy (RP) is relatively better oncological outcomes in patients with prostate cancer (PCa). However, the incidence of castration-resistant...  相似文献   
67.
Erythropoietic protoporphyria (EPP) is a disorder of heme synthesis that causes excessive accumulation of protoporphyrin. The predominant clinical feature is photosensitivity triggered by light at wavelengths near 400 nm. We describe a 52-year-old man with EPP who underwent aortic valve replacement due to severe regurgitation. To prevent burn injuries, astral lamps in the operating room were covered with yellow film filters. Preoperative autologous blood donation was not undertaken. Blood priming of the extracorporeal circuit was performed to maintain adequate hemoglobin concentrations, which resulted in reduction of heme synthesis. The patient was discharged in good health without any signs or symptoms of EPP.  相似文献   
68.
The Performance Dip is a newly characterized behavioral phenomenon, where, paradoxically, a weaker task-irrelevant visual stimulus causes larger disturbances on the accuracy of a main letter identification task than a stronger stimulus does. Understanding mechanisms of the Performance Dip may provide insight into unconsciousness behavior. Here, we investigated the generalization of the Performance Dip. Specifically, we tested whether the Performance Dip occurs in a motion-related Simon task, and if so, whether the Performance Dip involves the same brain region, that is, the dorsolateral prefrontal cortex (DLPFC), previously implicated in the Performance Dip, or the supplementary motor area (SMA) and pre-SMA, implicated in a motion-related Simon Task. Subjects made manual directional responses according to the color of stochastic moving dots while ignoring the global direction of moving dots, which could be either congruent or incongruent to the response appropriate to the main task. We found that weak incongruent task-irrelevant stimuli caused a Performance Dip, in which the SMA and pre-SMA, rather than DLPFC, played critical roles. Our results suggest a possible common brain mechanism across different neural circuits, in which weak, but not strong, task-irrelevant information is free from inhibition and intrudes into neural circuits relevant to the main task.  相似文献   
69.

Purpose

Although intussusception has been reported as quite a rare cause of jejunoileal atresia (JIA), pediatric surgeons have noted the frequent presence of intussusception as well as volvulus at surgery. The aim of this study was to investigate the contribution of intrauterine intussusception and volvulus to the development of JIA.

Methods

In 48 newborns (24 boys and 24 girls) treated for JIA at our hospital between 1978 and 2004, the operative and pathologic findings were reviewed.

Results

Intussusception was responsible for gap and cord type atresia in 12 cases (25%). The cord showed an atrophic intestinal lumen in 2 cases. Volvulus was observed in 13 cases. Volvulus and intussusception were simultaneously noted in 1 case. This suggested that intussusception was the cause of the atresia, whereas volvulus was a secondary event. Neither intussusception nor volvulus was observed in high jejunal, apple peel, or multiple atresia.

Conclusions

Intrauterine volvulus and intussusception were commonly observed in single mid- and low JIA. Thus, intrauterine intussusception may be a common cause of gap and cord type JIA. Volvulus may not only cause JIA but also result from anatomic changes after the development of JIA in some cases.  相似文献   
70.
Background: Intracranial arterial stenosis (ICAS) is an important cause of ischemic stroke worldwide due to its higher risk of recurrence with medical therapy. Although some large randomized studies failed to show the superiority of surgical treatment compared with medical therapy, the results of medical therapy are not sufficient. There are patients who still benefit from surgical treatment. This retrospective analysis aimed to evaluate the long-term efficacy of surgical therapy with percutaneous transluminal angioplasty and/or stenting (PTA/PTAS) or extracranial-intracranial (EC/IC) bypass surgery for patients with ICAS. Methods: Between October 2005 and December 2016, 55 ICAS patients were treated with PTA/PTAS or EC-IC bypass surgery. Their electronic medical records were retrospectively reviewed and analyzed. The primary outcome was all adverse events beyond 30 days after a revascularization procedure. Results: We performed 21 cases (35%) of PTA, 4 cases (7%) of PTAS, and 34 cases (58%) of EC-IC bypass surgery and the median follow-up duration was 66 months (range 1-144 months). The occurrence rate of the primary outcome was 10.2% and only 1 patient (1.8%) experienced ipsilateral disabling ischemic stroke beyond 30 days. The long-term functional independent survival rate was 83.6%. Conclusions: We demonstrated a long-term favorable outcome of combined surgical intervention for ICAS patients with PTA/PTAS and EC-IC bypass surgery, and the result was better than previously reported outcomes of medical therapy. Additional multicenter studies are required to draw firm conclusions on the efficacy of reduction of recurrent stroke in patients with ICAS.  相似文献   
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