BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma originates in the marginal zone of lymphoid tissue.lung is one of the most frequent non-gastrointestinal organs involved,here known as bronchus-associated lym...BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma originates in the marginal zone of lymphoid tissue.lung is one of the most frequent non-gastrointestinal organs involved,here known as bronchus-associated lymphoid tissue(BALT)lymphoma.BALT lymphoma of unknown etiology,and most patients are asymptomatic.The treatment of BALT lymphoma is controversial.CASE SUMMARY A 55-year-old man admitted to hospital had a three-month history of progressively coughing up yellow sputum,chest stuffiness,and shortness of breath.Fiberoptic bronchoscopy revealed mucosal visible beaded bumps 4 cm from the tracheal carina at 9 o'clock and 3 o'clock,the right main bronchus,and the right upper lobe bronchus.Biopsy specimens showed MALT lymphoma.Computed tomography virtual bronchoscopy(CTVB)showed uneven main bronchial wall thickening and multiple nodular protrusion.BALT lymphoma stage IE was diagnosed after a staging examination.We treated the patient with radiotherapy(RT)alone.A total dose of 30.6 Gy/17 f/25 d was given.The patient had no obvious adverse reactions during RT.The CTVB was repeated after RT and showed that the right side of the trachea was slightly thickened.CTVB was repeated 1.5 mo after RT and again showed that the right side of the trachea was slightly thickened.Annual CTVB showed no signs of recurrence.The patient now has no symptoms.CONCLUSION BALT lymphoma is an uncommon disease and shows good prognosis.The treatment of BALT lymphoma is controversial.In recent years,less invasive diagnostic and therapeutic approaches have been emerging.RT was effective and safe in our case.The use of CTVB could provide a noninvasive,repeatable,and accurate method in diagnosis and follow-up.展开更多
Background： Volumetric-modulated arc therapy （VMAT） can only be implemented on the new generation linacs such as the Varian Trilogy（R） and Elekta Synergy（R）.This prevents most existing linacs from delivering VM...Background： Volumetric-modulated arc therapy （VMAT） can only be implemented on the new generation linacs such as the Varian Trilogy（R） and Elekta Synergy（R）.This prevents most existing linacs from delivering VMAT.The purpose of this study was to investigate the feasibility of using a conventional linear accelerator delivering constant dose rate and constant angular spacing intensity-modulated arc therapy （CDR-CAS-IMAT） for treating cervical cancer.Methods： Twenty patients with cervical cancer previously treated with intensity-modulated radiation therapy （IMRT） using Varian Clinical 23EX were retreated using CDR-CAS-IMAT.The planning target volume （PTV） was set as 50.4 Gy in 28 fractions.Plans were evaluated based on the ability to meet the dose volume histogram.The homogeneity index （HI）, target volume conformity index （CI）, the dose to organs at risk, radiation delivery time, and monitor units （MUs） were also compared.The paired t-test was used to analyze the two data sets.All statistical analyses were performed using SPSS 19.0 software.Results： Compared to the IMRT group, the CDR-CAS-IMAT group showed better PTV CI （0.85 ＆#177; 0.03 vs.0.81 ＆#177; 0.03, P =0.001）, clinical target volume CI （0.46 ＆#177; 0.05 vs.0.43 ＆#177; 0.05, P =0.001）, HI （0.09＆#177;0.02 vs.0.11 ＆#177; 0.02, P =0.005） and D95 （5196.33 ＆#177; 28.24 cGy vs.5162.63 ＆#177; 31.12 cGy, P =0.000）, and cord D2 （3743.8 ＆#177; 118.7 cGy vs.3806.2 ＆#177; 98.7 cGy, P =0.017） and rectum V40 （41.9 ＆#177; 6.1% vs.44.2 ＆#177; 4.8%, P =0.026）.Treatment time （422.7 ＆#177; 46.7 s vs.84.6 ＆#177; 7.8 s, P =0.000） and the total plan Mus （927.4 ＆#177; 79.1 vs.787.5 ＆#177; 78.5, P =0.000） decreased by a factor of 0.8 and 0.15, respectively.The IMRT group plans were superior to the CDR-CAS-IMAT group plans considering decreasing bladder V50 （17.4 ＆#177; 4.5% vs.16.6 ＆#177; 4.2%, P =0.049）, bowel V30 （39.6 ＆#177; 6.5% vs.36.6 ＆#177; 7.5%, P =0.008）, and low-dose irradiation volume;there were no significant differences in other statistical indexes.Conclusions： Patients with cervical cancer treated with CDR-CAS-IMAT using Varian Clinical 23EX can get equivalent or superior dose distribution compared to those treated with IMRT.CDR-CAS-IMAT has a less treatment time and MU, which can reduce the uncertainty factor and patient discomfort in treatment.展开更多
Working memory plays an important role in human cognition. This study investigated how working memory was encoded by the power of multichannel local field potentials （LFPs） based on sparse non negative matrix factor...Working memory plays an important role in human cognition. This study investigated how working memory was encoded by the power of multichannel local field potentials （LFPs） based on sparse non negative matrix factorization （SNMF）. SNMF was used to extract features from LFPs recorded from the prefrontal cortex of four SpragueDawley rats during a memory task in a Y maze, with 10 trials for each rat. Then the powerincreased LFP components were selected as working memoryrelated features and the other components were removed. After that, the inverse operation of SNMF was used to study the encoding of working memory in the time frequency domain. We demonstrated that theta and gamma power increased significantly during the working memory task. The results suggested that postsynaptic activity was simulated well by the sparse activity model. The theta and gamma bands were meaningful for encoding working memory.展开更多
文摘BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma originates in the marginal zone of lymphoid tissue.lung is one of the most frequent non-gastrointestinal organs involved,here known as bronchus-associated lymphoid tissue(BALT)lymphoma.BALT lymphoma of unknown etiology,and most patients are asymptomatic.The treatment of BALT lymphoma is controversial.CASE SUMMARY A 55-year-old man admitted to hospital had a three-month history of progressively coughing up yellow sputum,chest stuffiness,and shortness of breath.Fiberoptic bronchoscopy revealed mucosal visible beaded bumps 4 cm from the tracheal carina at 9 o'clock and 3 o'clock,the right main bronchus,and the right upper lobe bronchus.Biopsy specimens showed MALT lymphoma.Computed tomography virtual bronchoscopy(CTVB)showed uneven main bronchial wall thickening and multiple nodular protrusion.BALT lymphoma stage IE was diagnosed after a staging examination.We treated the patient with radiotherapy(RT)alone.A total dose of 30.6 Gy/17 f/25 d was given.The patient had no obvious adverse reactions during RT.The CTVB was repeated after RT and showed that the right side of the trachea was slightly thickened.CTVB was repeated 1.5 mo after RT and again showed that the right side of the trachea was slightly thickened.Annual CTVB showed no signs of recurrence.The patient now has no symptoms.CONCLUSION BALT lymphoma is an uncommon disease and shows good prognosis.The treatment of BALT lymphoma is controversial.In recent years,less invasive diagnostic and therapeutic approaches have been emerging.RT was effective and safe in our case.The use of CTVB could provide a noninvasive,repeatable,and accurate method in diagnosis and follow-up.
基金This study was partially supported by a grant from the Medical Science Foundation of the Health Department of Hebei Province
文摘Background： Volumetric-modulated arc therapy （VMAT） can only be implemented on the new generation linacs such as the Varian Trilogy（R） and Elekta Synergy（R）.This prevents most existing linacs from delivering VMAT.The purpose of this study was to investigate the feasibility of using a conventional linear accelerator delivering constant dose rate and constant angular spacing intensity-modulated arc therapy （CDR-CAS-IMAT） for treating cervical cancer.Methods： Twenty patients with cervical cancer previously treated with intensity-modulated radiation therapy （IMRT） using Varian Clinical 23EX were retreated using CDR-CAS-IMAT.The planning target volume （PTV） was set as 50.4 Gy in 28 fractions.Plans were evaluated based on the ability to meet the dose volume histogram.The homogeneity index （HI）, target volume conformity index （CI）, the dose to organs at risk, radiation delivery time, and monitor units （MUs） were also compared.The paired t-test was used to analyze the two data sets.All statistical analyses were performed using SPSS 19.0 software.Results： Compared to the IMRT group, the CDR-CAS-IMAT group showed better PTV CI （0.85 ＆#177; 0.03 vs.0.81 ＆#177; 0.03, P =0.001）, clinical target volume CI （0.46 ＆#177; 0.05 vs.0.43 ＆#177; 0.05, P =0.001）, HI （0.09＆#177;0.02 vs.0.11 ＆#177; 0.02, P =0.005） and D95 （5196.33 ＆#177; 28.24 cGy vs.5162.63 ＆#177; 31.12 cGy, P =0.000）, and cord D2 （3743.8 ＆#177; 118.7 cGy vs.3806.2 ＆#177; 98.7 cGy, P =0.017） and rectum V40 （41.9 ＆#177; 6.1% vs.44.2 ＆#177; 4.8%, P =0.026）.Treatment time （422.7 ＆#177; 46.7 s vs.84.6 ＆#177; 7.8 s, P =0.000） and the total plan Mus （927.4 ＆#177; 79.1 vs.787.5 ＆#177; 78.5, P =0.000） decreased by a factor of 0.8 and 0.15, respectively.The IMRT group plans were superior to the CDR-CAS-IMAT group plans considering decreasing bladder V50 （17.4 ＆#177; 4.5% vs.16.6 ＆#177; 4.2%, P =0.049）, bowel V30 （39.6 ＆#177; 6.5% vs.36.6 ＆#177; 7.5%, P =0.008）, and low-dose irradiation volume;there were no significant differences in other statistical indexes.Conclusions： Patients with cervical cancer treated with CDR-CAS-IMAT using Varian Clinical 23EX can get equivalent or superior dose distribution compared to those treated with IMRT.CDR-CAS-IMAT has a less treatment time and MU, which can reduce the uncertainty factor and patient discomfort in treatment.
基金supported by the National Natural Science Foundation of China (61074131 and 91132722)the Doctoral Fund of the Ministry of Education of China (21101202110007)
文摘Working memory plays an important role in human cognition. This study investigated how working memory was encoded by the power of multichannel local field potentials （LFPs） based on sparse non negative matrix factorization （SNMF）. SNMF was used to extract features from LFPs recorded from the prefrontal cortex of four SpragueDawley rats during a memory task in a Y maze, with 10 trials for each rat. Then the powerincreased LFP components were selected as working memoryrelated features and the other components were removed. After that, the inverse operation of SNMF was used to study the encoding of working memory in the time frequency domain. We demonstrated that theta and gamma power increased significantly during the working memory task. The results suggested that postsynaptic activity was simulated well by the sparse activity model. The theta and gamma bands were meaningful for encoding working memory.
