Regularity-Constrained Fast Sine Transforms

This letter proposes a fast implementation of the regularity-constrained discrete sine transform (R-DST). The original DST \textit{leaks} the lowest frequency (DC: direct current) components of signals into high frequency (AC: alternating current) subbands. This property is not desired in many applications, particularly image processing, since most of the frequency components in natural images concentrate in DC subband. The characteristic of filter banks whereby they do not leak DC components into the AC subbands is called \textit{regularity}. While an R-DST has been proposed, it has no fast implementation because of the singular value decomposition (SVD) in its internal algorithm. In contrast, the proposed regularity-constrained fast sine transform (R-FST) is obtained by just appending a regularity constraint matrix as a postprocessing of the original DST. When the DST size is $M\times M$ ($M=2^\ell$, $\ell\in\mathbb{N}_{\geq 1}$), the regularity constraint matrix is constructed from only $M/2-1$ rotation matrices with the angles derived from the output of the DST for the constant-valued signal (i.e., the DC signal). Since it does not require SVD, the computation is simpler and faster than the R-DST while keeping all of its beneficial properties. An image processing example shows that the R-FST has fine frequency selectivity with no DC leakage and higher coding gain than the original DST. Also, in the case of $M=8$, the R-FST saved approximately $0.126$ seconds in a 2-D transformation of $512\times 512$ signals compared with the R-DST because of fewer extra operations

Primary Tracheal Malignant Lymphoma Detected during a Regular Checkup in an Asbestos Dust-Exposed Smoker

Primary tracheal malignant lymphoma is a rare disease;only 30 cases have been reported to date. A 73-year-old Japanese man with a history of asbestos exposure was undergoing biannual chest computed tomography (CT) twice a year as a routine procedure for those previously exposed to asbestos. He had been smoking since the age of 32. In September 2010, chest CT during this regular checkup revealed a polypoid lesion in his trachea and pleural plaques, which were suspected to be caused by asbestos. Bronchoscopy performed in October revealed a polypoid lesion with granules and nodules in the trachea. A diagnosis of non-Hodgkin lymphoma (NHL) and extranodal marginal-zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) was confirmed by histological analysis of the biopsy specimens. To our knowledge, this is the first case of primary tracheal lymphoma associated with a history of asbestos exposure. Several reports have documented no correlation between asbestos and malignant lymphoma. In addition, the correlation between smoking and NHL is weak. Although we cannot exclude the possibility of a simple coincidence of asbestos, smoking, and tracheal lymphoma, this case suggests that asbestos and smoking might have multiplicative effects in the development or progression of tracheal lymphoma

Elevated levels of plasma lactate dehydrogenase is an unfavorable prognostic factor in patients with epidermal growth factor receptor mutation-positive non-small cell lung cancer, receiving treatment with gefitinib or erlotinib.

Treatment with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has been shown to prolong survival in patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). The present study performed a retrospective analysis to investigate the association between the plasma lactate dehydrogenase (LDH) levels and survival in patients with EGFR mutation-positive NSCLC receiving treatment with EGFR-TKIs. The medical charts of patients with EGFR mutation-positive NSCLC who were receiving treatment with EGFR-TKIs at Toyama University Hospital between 2007 and 2014 were assessed. The data from 65 patients were included in the analysis. Patients with higher plasma LDH levels exhibited shorter progression-free survival (6.2 vs. 13.2 months; P<0.01) and overall survival (10.5 vs. 36.1 months; P<0.01) periods compared with patients with lower plasma LDH levels. A Cox proportional hazards model identified that the plasma LDH level was associated with the progression-free survival (P=0.05) and overall survival (P<0.01). An association was demonstrated between the pretreatment plasma LDH level and the survival in patients with EGFR mutation-positive NSCLC receiving treatment with EGFR-TKIs. Close observation is required in EGFR mutation-positive NSCLC patients exhibiting high plasma LDH levels following the initiation of treatment with EGFR-TKIs.出版社サイトへのリンク：https://doi.org/10.3892/mco.2016.77

ガン カガク リョウホウ ニオケル ショウカカン ドクセイ ト ケッセイ Diamine Oxidase DAO カッセイ ニ カンスル ケントウ

There are so many patients with advanced gastric cancer who undergo systemic chemotherapy worldwide. The quality of life（QOL）of patients with gastric cancer who receive chemotherapy is often lowed by various gastrointestinal toxicities during the chemotherapy. Nutrition is also impaired by gastrointestinal toxicities. However, it is difficult to predict their occurrence in advance and further there is no good serum marker for nutrition in the patients treated with chemotherapy. Thus, it is important to objectively evaluate and predict the toxicity of the digestive tract during cancer chemotherapy. Diamine Oxidase（DAO）is an enzyme that is expressed in intestinal epithelial cells. Recently it has been reported that DAO activity may reflect damage or atrophy of the intestinal villi, and therefore it may be a sensitive serum marker for nutritional state. In this study, we measured serum DAO activity of patients with gastric cancer treated with systemic chemotherapy, and investigated the correlation between DAO activity and gastrointestinal toxicities. Six patients with gastric cancer, who were treated by docetaxel+cisplatin+S‐１combination chemotherapy, were enrolled. DAO activity was measured by sensitive colorimetric assay. DAO activities diminished after treatment in４patients with moderate to severe gastrointestinal toxicities. In contrast, they did not change in２patients with no gastrointestinal toxicities. Our results may suggest that DAO activity is a good serum marker for the gastrointestinal toxicities as well as nutrition state in patients who receive systemic chemotherapy. More large scale study is needed to warrant