Hepatocellular carcinoma(HCC), with its high incidence and mortality rate, is one of the most common malignant tumors. Despite recent development of a diagnostic and treatment method, the prognosis of HCC remains poor...Hepatocellular carcinoma(HCC), with its high incidence and mortality rate, is one of the most common malignant tumors. Despite recent development of a diagnostic and treatment method, the prognosis of HCC remains poor. Therefore, to provide optimal treatment for each patient with HCC, more precise and effective biomarkers are urgently needed which could facilitate a more detailed individualized decision-making during HCC treatment, including the following; risk assessment, early cancer detection, prediction of treatment or prognostic outcome. In the blood of cancer patients, accumulating evidence about circulating tumor cells and cell-free nucleic acids has suggested their potent clinical utilities as novel biomarker. This concept, so-called "liquid biopsy" is widely known as an alternative approach to cancer tissue biopsy. This method might facilitate a more sensitive diagnosis and better decision-making by obtaining genetic and epigenetic aberrations that are closely associated with cancer initiation and progression. In this article, we review recent developments based on the available literature on both circulating tumor cells and cell-free nucleic acids in cancer patients, especially focusing on Hepatocellular carcinoma.展开更多
AIM： To evaluate the efficacy of continuous regional arterial infusion therapy （CRAI） with gabexate mesilate and antibiotics for severe acute pancreatitis （SAP）. METHODS： We conducted a prospective study on pati...AIM： To evaluate the efficacy of continuous regional arterial infusion therapy （CRAI） with gabexate mesilate and antibiotics for severe acute pancreatitis （SAP）. METHODS： We conducted a prospective study on patients who developed SAP with or without CRAI. Out of 18 patients fulfilled clinical diagnostic criteria for SAP in Japan, 9 patients underwent CRAI, while 9 patients underwent conventional systemic protease inhibitor and antibiotics therapy （non-CRAI）. CRAI was initiated within 72 h of the onset of pancreatitis. Gabexate mesilate （2400 mg/d） was continuously administered for 3 to 5 d. The clinical outcome including serum inflammation-related parameters were examined. RESULTS- The duration of abdominal pain in the CRAI group was 1.9 =1：0.26 d, whereas that in the non-CRAI group was 4.3 ±0.50. The duration of SIRS in the CRAI group was 2.2 ± 0.22 d, whereas that in the non- CRAI group was 3.2 ± 0.28. Abdominal pain and SIRS disappeared significantly in a short period of time after the initiation of CRAI using gabexate mesilate. The average length of hospitalization significantly differed between the CRAI and non-CRAI groups, 53.3 ± 7.9 d and 87.4± 13.9 d, respectively. During the first two weeks, levels of serum CRP and the IL6/IL10 ratio in the CRAI group tended to have a rapid decrease compared to those in the non-CRAI group. CONCLUSION： The present results suggest that CRAI using gabexate mesilate was effective against SAP.展开更多
A 58-year-old Japanese man had tarry stool and severe anemia. Neither upper nor lower gastrointestinal （GI） endoscopy showed any localized lesions. Thus, the source of his GI bleeding was suspected to be in the smal...A 58-year-old Japanese man had tarry stool and severe anemia. Neither upper nor lower gastrointestinal （GI） endoscopy showed any localized lesions. Thus, the source of his GI bleeding was suspected to be in the small intestine, and he underwent peroral double-balloon enteroscopy （DBE） using EN-450T5 （Fujinon-Toshiba ES System Co., Tokyo, Japan）. There were no lesions considered to be the source of GI bleeding. After the procedure, the patient began to experience abdominal pain. Laboratory tests revealed hyperamylasemia and abdominal computed tomography revealed an inflammation of the pancreas and the peripancreas. He was thus diagnosed to have acute pancreatitis. Conservative treatments resulted in both clinical and laboratory amelioration. He had no history of alcohol ingestion, gallstone disease or pancreatitis. Magnetic resonance cholangiopancreatography demonstrated no structural alterations and no stones in the pancreatobiliary ductal system. As his abdominal pain started after the procedure, his acute pancreatitis was thus thought to have been related to the peroral DBE. This is the first reported case of acute pancreatitis probably associated with peroral DBE.展开更多
AIM To investigate the clinicopathological features of the patients testing negative for high titer serum antiHelicobacter pylori(H. pylori) antibody.METHODS The antibody titers were measured using antigens derived fr...AIM To investigate the clinicopathological features of the patients testing negative for high titer serum antiHelicobacter pylori(H. pylori) antibody.METHODS The antibody titers were measured using antigens derived from Japanese individuals. ^(13)C-urea breath test-positive individuals were defined as having H. pylori infection. We investigated the demographic characteristics, laboratory data, endoscopic findings including Kyoto classification of gastritis, and histology in negative-high titer patients without H. pylori eradication therapy. Kyoto classification consisted of scores for gastric atrophy, intestinal metaplasia, enlarged folds, nodularity, and redness.RESULTS Of the 136 subjects enrolled, 23(17%) had H. pylori infection. Kyoto classification had an excellent area under the receiver operating characteristics curve(0.886, 95% confidence interval: 0.803-0.968, P = 3.7 × 10^(-20)) for predicting H. pylori infection with a cutoff value of 2. Further, Kyoto classification, H. pylori density, and neutrophil activity had high accuracies(89.7%, 96.3%, and 94.1%, respectively). Kyoto classification was independent of the demographic and laboratory parameters in multivariate analysis.CONCLUSION Endoscopic Kyoto classification of gastritis is a useful predictor of H. pylori infection in negative-high titer antibody patients.展开更多
Despite recent advances in surgical techniques and perioperative management, the prognosis of pancreatic cancer(PCa) remains extremely poor. To provide optimal treatment for each patient with Pca, superior biomarkers ...Despite recent advances in surgical techniques and perioperative management, the prognosis of pancreatic cancer(PCa) remains extremely poor. To provide optimal treatment for each patient with Pca, superior biomarkers are urgently needed in all phases of management from early detection to staging, treatment monitoring, and prognosis. In the blood of patients with cancer, circulating tumor cells(CTCs) and cell-free nucleic acids(cf NAs), such as DNA, m RNA, and noncoding RNA have been recognized. In the recent years, their presence in the blood has encouraged researchers to investigate their potential use as novel blood biomarkers, and numerous studies have demonstrated their potential clinical utility as a biomarker for certain types of cancer. This concept, called "liquid biopsy" has been focused on as a less invasive, alternative approach to cancer tissue biopsy for obtaining genetic and epigenetic aberrations that contribute to oncogenesis and cancer progression. In this article, we review the available literature on CTCs and cfN As in patients with cancer, particularly focusing on PCa, and discuss future perspectives in this field.展开更多
Basaloid squamous cell carcinoma （BSC） of the esophagus is a rare malignant disease. We report here a patient with recurrent esophageal BSC, who was successfully treated by systemic chemotherapy containing 5-fluorou...Basaloid squamous cell carcinoma （BSC） of the esophagus is a rare malignant disease. We report here a patient with recurrent esophageal BSC, who was successfully treated by systemic chemotherapy containing 5-fluorouracil （5-FU） and cisplatin （CDDP）. A 57-year-old woman was diagnosed as having SCluamous cell carcinoma of the esophagus upon endoscopic examination. Curative esophagectomy with lymph node dissection was performed under the thoracoscope. The pathological diagnosis of the surgical specimen was BSC. Five months after operation, the patient was diagnosed as having a recurrence of the BSC with metastases to the liver and spleen, and a right paraclavicular lymph node. She was given systemic chemotherapy consisting of continuous infusion of 800 mg/d of 5-FU and 3 h infusion of 20 mg/d of CDDP for 5 consecutive days every 4 wk. The metastatic lesions in the spleen and right paraclavicular lymph node disappeared, and the liver metastasis was apparently reduced in size after 2 courses of chemotherapy. The tumor regression was seen over 6 courses, with progression afterwards. Although subsequent treatment with CPT-11 and CDDP was not effective, docetaxel and vinorelbine temporarily controlled the tumor growth for 2 mo. 5-FU and CDDP combination may be useful for the patients with advanced BSC.展开更多
AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout th...AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout the study. The expression of LPA receptors was confirmed by reverse-transcript polymerase chain reaction (RT-PCR). Cytosolic free calcium was measured by fluorescent calcium indicator fura-2, and the localization of NF-κB was visualized by immunofluorescent method with or without various agents, which effect cell signaling. RESULTS: Panc-1 expressed LPA receptors, LPA1, LPA2 and LPA3. LPA caused the elevation of cytosolic free calcium dose-dependently. LPA also caused the nuclear translocation of NF-κB. Cytosolic free calcium was attenuated by pertussis toxin (PTX) and U73122, an inhibitor of phospholipase C. The translocation of NF-κB was similarly attenuated by PTX and U73122, but phorbol ester, an activator of protein kinase C, alone did not translocate NF-κB. Furthermore, the translocation of NF-κB was completely blocked by Ca2+ chelator BAPTA-AM. Thapsigargin, an endoplasmic- reticulum Ca2+-ATPase pump inhibitor, also promoted the translocation of NF-κB. Staurosporine, a proteinkinase C inhibitor, attenuated translocation of NF-κB induced by LPA. CONCLUSION: These findings suggest that protein kinase C is activated endogenously in Panc-1, and protein kinase C is essential for activating NF-κB with cytosolic calcium and that LPA induces the nuclear translocation of NF-κB in Panc-1 by mobilizing cytosolic free calcium.展开更多
Synovial sarcoma(SS) is genetically characterized by chromosomal translocation, which generates SYT-SSX fusion transcripts. Although SS can occur in any body part, primary gastric SS is substantially rare. Here we des...Synovial sarcoma(SS) is genetically characterized by chromosomal translocation, which generates SYT-SSX fusion transcripts. Although SS can occur in any body part, primary gastric SS is substantially rare. Here we describe a detection of the fusion gene sequence of gastric SS in plasma cell-free DNA(cf DNA). A gastric submucosal tumor was detected in the stomach of a 27-year-old woman and diagnosed as SS. Candidate intronic primers were designed to detect the intronic fusion breakpoint and this fusion sequence was confirmed in intron 10 of SYT and intron 5 of SSX2 by genomic polymerase chain reaction(PCR) and direct sequencing. A locked nucleic acid(LNA) probe specificto the fusion sequence was designed for detecting the fusion sequence in plasma and the fusion sequence was detected in preoperative plasma cfD NA, while not detected in postoperative plasma cfD NA. This technique will be useful for monitoring translocation-derived diseases such as SS.展开更多
AIM:To evaluate the chemoradiotherapy for locally advanced pancreatic cancer utilizing low dose gemcitabine as a radiation sensitizer administered twice weekly. METHODS: We performed a retrospective analysis of chemor...AIM:To evaluate the chemoradiotherapy for locally advanced pancreatic cancer utilizing low dose gemcitabine as a radiation sensitizer administered twice weekly. METHODS: We performed a retrospective analysis of chemoradiotherapy utilizing gemcitabine administered twice weekly at a dose of 40 mg/m2. After that, maintenance systemic chemotherapy with gemcitabine, at a dose of 1000 mg/m2, was administered weekly for 3 wk with 1-wk rest until disease progression or unacceptable toxicity developed. RESULTS: Eighteen patients with locally advanced unresectable pancreatic cancer were enrolled. Three of those patients could not continue with the therapy; one patient had interstitial pneumonia during radiation therapy and two other patients showed liver metastasis or peritoneal metastasis during an early stage of the therapy. The median survival was 15.0 mo and the overall 1-year survival rate was 60%, while the median progression-free survival was 8.0 mo. The subgroup which showed the reduction of tumor development, more than 50% showed a tendency for a better prognosis; however, other parameters including age, gender and performance status did not correlate with survival. The median survival of the groups that died of liver metastasis and peritoneal metastasis were 13.0 mo and 27.7 mo, respectively.CONCLUSION: Chemoradiotherapy with low-dose gemcitabine administered twice weekly could be effective to patients with locally advanced pancreatic cancer; however, patients developing liver metastases had a worse prognosis. Another chemoradiotherapy strategy might be needed for those patients, such as administrating one or two cycles of chemotherapy initially, followed by chemoradiotherapy for the cases with no distant metastases.展开更多
AIM: To determine the distribution of Hepatitis B virus (HBV) genotypes in Benin, and to clarify the virological characteristics of the dominant genotype.METHODS: Among 500 blood donors in Benin, 21 HBsAg-positive don...AIM: To determine the distribution of Hepatitis B virus (HBV) genotypes in Benin, and to clarify the virological characteristics of the dominant genotype.METHODS: Among 500 blood donors in Benin, 21 HBsAg-positive donors were enrolled in the study. HBV genotypes were determined by enzyme immunoassay and restriction fragment length polymorphism. Complete genome sequences were determined by PCR and direct sequencing.RESULTS: HBV genotype E (HBV/E) was detected in 20/21 (95.2%), and HBV/A in 1/21 (4.8%). From the age-specific prevalence of HBeAg to anti-HBe seroconversion (SC) in 19 HBV/E subjects, SC was estimated to occur frequently in late teens in HBV/E.The comparison of four complete HBV/E genomes from HBeAg-positive subjects in this study and five HBV/E sequences recruited from the database revealed that HBV/E was distributed throughout West Africa with very low genetic divers ity (nucleotide homology 96.7-99.2%).Based on the sequences in the basic core promoter (BCP)to precore region of the nine HBV/E isolates compared to those of the other genotypes, a nucleotide substitution in the BCP, G1757A, was observed in HBV/E.CONCLUSION: HBV/E is predominant in the Republic of Benin, and SC is estimated to occur in late teens in HBV/E. The specific nucleotide substitution G1757A in BCP, which might influence the virological characteristics,is observed in HBV/E.展开更多
Objective: To Assess the correlation between different quality analysis parameters of trabecular pattern in digital panoramic radiographies and relations with forearm bone mass density (BMD) performed by DXA. Methods:...Objective: To Assess the correlation between different quality analysis parameters of trabecular pattern in digital panoramic radiographies and relations with forearm bone mass density (BMD) performed by DXA. Methods: The study was developed using panoramic and peripheral bone densitometry dual energy X-ray absorptiometry (DXA) of 68 patients, 9 males and 59 females (19 - 73 years old). In the panoramic radiographs, evaluation of the trabecular bone morphology through assessment of fractal dimension (FD), connectivity (C) and total number of “bright” pixels (ET) was performed. In DXA, the exam determines the bone mineral density of the forearm to identify who has a high risk of osteoporosis. Statistics analyzed the relationship of these exams and the contribution of dental radiographs in detecting patients at risk for osteoporosis. Results: The average age of subjects was 43.85. In the analysis of trabecular pattern, a significant correlation between the FD, ET and C factors in level of 5% (Pearson correlation test) was found. Correlation tests showed no significant correlation between DF and BMD. Conclusions: The analysis showed correlations with each other, detecting alterations in the trabecular pattern. It cannot be related to BMD with FD but should be taken into account that examining the bone or trabecular alveolar process, when, for example, diagnostic analysis of pre-implant bone quality, is required.展开更多
BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid sc...BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types.Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types.However,it remains unclear whether ANO5 acts as a plasma membrane chloride channel,and its expression and functions in gastric cancer(GC)have not been investigated.AIM To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.METHODS Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines,and changes in cell proliferation,cell cycle progression,apoptosis,and cellular movement were assessed.The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis.Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.RESULTS Reverse transcription-quantitative polymerase chain reaction(PCR)and western blotting demonstrated high ANO5 mRNA and protein expression,respectively,in NUGC4 and MKN45 cells.In these cells,ANO5 silencing inhibited cell proliferation and induced apoptosis.In addition,the knockdown of ANO5 inhibited G1-S phase progression,invasion,and migration.The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes,such as CDKN1A,CDK2/4/6,CCNE2,and E2F1,in ANO5-depleted NUGC4 cells.The expression of these genes was verified using reverse transcription-quantitative PCR.Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis.Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC(P=0展开更多
To have an insight into the occurrence of inverse Hall-Petch relationship in ultrafine-grained(UFG) aluminum alloys produced by severe plastic deformation(SPD),ultra-SPD(i.e.inducing several ten thousand shear strains...To have an insight into the occurrence of inverse Hall-Petch relationship in ultrafine-grained(UFG) aluminum alloys produced by severe plastic deformation(SPD),ultra-SPD(i.e.inducing several ten thousand shear strains via high-pressure torsion,HPT) followed by aging is applied to an Al-La-Ce alloy.Average nanograin sizes of 40 and 80 nm are successfully achieved together with strain-induced Lomer-Cottrell dislocation lock formation and aging-induced semi-coherent Al_(11)(La,Ce)_3 precipitation.Analysis of hardening mechanisms in this alloy compared to SPD-processed pure aluminum with micrometer grain sizes,SPD-processed Al-based alloys with submicrometer grain sizes and ultra-SPD-processed Al-Ca alloy with nanograin sizes reveals the presence of two breaks in the Hall-Petch relationship.First,a positive upbreak appears when the grain sizes decrease from micrometer to submicrometer which is due to extra hardening by solute-dislocation interactions.Second,a negative down-break and softening occur by decreasing the grain sizes from submicrometer to nanometer which is caused by weakening the dislocation hardening mechanism with minor contribution of the inverse Hall-Petch mechanism.Detailed analyses confirm that nanograin formation is not necessarily a solution for extra hardening of Al-based alloys and other accompanying strategies such as grain-boundary segregation and precipitation are required to overcome such a down-break and softening.展开更多
Background:Although diagnostic ultrasound can non-invasively capture the image of abdominal viscera,diagnosis of the continuous ultrasound liver images to detect a liver tumor effectively and to determine whether the ...Background:Although diagnostic ultrasound can non-invasively capture the image of abdominal viscera,diagnosis of the continuous ultrasound liver images to detect a liver tumor effectively and to determine whether the detected is benign or malignant is nontrivial.In order to minimize the gaps in diagnostic accuracy depending on doctor’s proficiency,we built an automated system to support the ultrasonography of liver tumors by employing deep learning technologies.Methods:We constructed a neural network model for the automated detection of tumor tissues and blood vessels from the sequential liver ultrasound images.Faster region-based convolutional neural networks(Faster R-CNN)is employed as a base model for the object detection,which can output the detection results in 4 frames per second and enable the system to be particularly suitable for the real time ultrasonography.Moreover,we proposed a new neural network architecture feeding both the current and previous images into Faster R-CNN.For training the models,intraoperative ultrasound images obtained from one hepatocellular carcinoma(HCC)patient were used.The obtained image was a multifaceted observation of the liver and includes one HCC and some blood vessels.We labeled 91 images with the help of a liver specialist.We compared the tumor detection performance of the plain Faster R-CNN model with that of the proposed model.Results:We find that both the models performed well in detecting HCC and blood vessels,after training with 400 epochs using Adam.However,the mean precision of our model reaches 0.549,which is 0.019 better than that of the plain Faster R-CNN,and the mean sensitivity of our model about HCC reaches 0.623±0.385 for 30 scenes of sequential liver ultrasound images,which is also 0.146 better than that of the plain Faster R-CNN model.Conclusions:The comparison between the proposed model and the plain Faster R-CNN model shows that we achieved better accuracy in tumor detection,in terms of the mean precision as well as the mean sensitivity,with the propo展开更多
Previous clinical trials have demonstrated the efficacy of yokukansan, a traditional Japanese medicine, for the treatment of behavioral and psychological symptoms of dementia (BPSD). However, less evidence is availabl...Previous clinical trials have demonstrated the efficacy of yokukansan, a traditional Japanese medicine, for the treatment of behavioral and psychological symptoms of dementia (BPSD). However, less evidence is available for the treatment of BPSD with yokukansankachimpihange (YKSCH), which consists of yokukansan and two additional herbal ingredients. The present study was conducted to investigate the efficacy and safety of YKSCH for treating BPSD in patients with Alzheimer’s disease (AD). We enrolled outpatients with mild-to-moderate AD who exhibited BPSD and obtained a Neuropsychiatric Inventory (NPI) score of >3 including subscale scores for “agitation”, “anxiety”, “irritability”, and “sleep and night-time behavior change”. A daily YKSCH dose of 7.5 g was administered for 12 weeks with concomitant administration of anti-dementia medication. BPSD was evaluated using the NPI at baseline and every 4 weeks during the intervention. We also examined apathy using the Japanese translation of the Apathy Scale, the short version of the Japanese version of the Zarit Caregiver Burden Interview, and the Modified Crichton Rating Scale for Predicting Activities of Daily Living. Cognitive dysfunction was evaluated using the Mini Mental State Examination and the AD Assessment Scale-Cognitive (Japanese version). Five participants were enrolled. The NPI total score tended to decrease between the baseline and 8-week evaluations during the YKSCH intervention (Wilcoxon signed rank test, P = 0.063). In terms of the NPI subscale scores, “apathy”, “agitation”, “delusions”, and “sleep and night-time behavior change” decreased after the intervention in those who exhibited each symptom at baseline. There were no significant differences in the other scores examined. No serious adverse events were observed. YKSCH could ameliorate BPSD in patients with mild-to-moderate AD with agitation, anxiety, irritability, and sleep and night-time behavior change, and it was well-tolerated.展开更多
Background: According to the treatment guidelines for gastric cancer in Japan (3rd edition), D1 lymphadenectomy is recommended for T1a cancer (out of indication for endoscopic resection) and a group of T1b cancer (dif...Background: According to the treatment guidelines for gastric cancer in Japan (3rd edition), D1 lymphadenectomy is recommended for T1a cancer (out of indication for endoscopic resection) and a group of T1b cancer (differentiated type, not larger than 1.5cm and clinically N0). D1+ lymphadenectomy is recommended for T1b cancer other than above group. D2 lymphadenectomy is for clinically N+ early gastric cancer (EGC). Methods: Consecutive 1141 resected EGC cases in our institution from January 1991 to December 2013 were analyzed. The size, depth of wall invasion, presence of ulcer, histological type and distribution of metastasis positive lymph node were evaluated. Results: There were 678 T1a and 463 T1b cancers. Lymph node metastasis positive T1a were 11 cases. All of them were undifferentiated type and the metastasis positive lymph nodes were all confined to the D1 area. Lymph node metastasis positive T1b cancer was 82 cases. Among them, 70 cases were within D1 area, 77 cases were within D1+ area and 79 cases were within D2 area. The other 3 cases had metastasis positive lymph node in beyond the D2 area. Conclusion: D1 lymphadenectomy is enough for T1a EGC that is out of indication of endoscopic resection and D1+ lymphadenectomy is reasonable for T1b EGC. These cases are good indication of laparoscopic surgery. D2 lymphadenectomy is required for T1b undifferentiated cancers which size is larger than 4 cm.展开更多
The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other ...The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other layer without, and (2) both NiFe layershave anisotropy normal each other. The domain wall migration and magnetization rotation processes in each of NiFe layers could be observed separately. The presence of magnetic anisotropy in the magnetic layer effectively controls the behavior of magnetic domains. Theinteraction between the two NiFe layers of the film could be observed not so strong in the present experiment.展开更多
The three-dimensional（3D） Dirac semimetals have linearly dispersive 3D Dirac nodes where the conduction band and valence band are connected. They have isolated 3D Dirac nodes in the whole Brillouin zone and can be v...The three-dimensional（3D） Dirac semimetals have linearly dispersive 3D Dirac nodes where the conduction band and valence band are connected. They have isolated 3D Dirac nodes in the whole Brillouin zone and can be viewed as a 3D counterpart of graphene. Recent theoretical calculations and experimental results indicate that the 3D Dirac semimetal state can be realized in a simple stoichiometric compound A3Bi（A = Na, K, Rb）. Here we report comprehensive high-resolution angle-resolved photoemission（ARPES） measurements on the two cleaved surfaces,（001） and（100）, of Na3Bi. On the（001） surface, by comparison with theoretical calculations, we provide a proper assignment of the observed bands, and in particular, pinpoint the band that is responsible for the formation of the three-dimensional Dirac cones. We observe clear evidence of 3D Dirac cones in the three-dimensional momentum space by directly measuring on the kx–ky plane and by varying the photon energy to get access to different out-of-plane kzs. In addition, we reveal new features around the Brillouin zone corners that may be related with surface reconstruction. On the（100） surface, our ARPES measurements over a large momentum space raise an issue on the selection of the basic Brillouin zone in the（100） plane. We directly observe two isolated 3D Dirac nodes on the（100） surface. We observe the signature of the Fermi-arc surface states connecting the two 3D Dirac nodes that extend to a binding energy of ~150 me V before merging into the bulk band. Our observations constitute strong evidence on the existence of the Dirac semimetal state in Na3Bi that are consistent with previous theoretical and experimental work. In addition, our results provide new information to clarify on the nature of the band that forms the3 D Dirac cones, on the possible formation of surface reconstruction of the（001） surface, and on the issue of basic Brillouin zone selection for the（100） surface.展开更多
文摘Hepatocellular carcinoma(HCC), with its high incidence and mortality rate, is one of the most common malignant tumors. Despite recent development of a diagnostic and treatment method, the prognosis of HCC remains poor. Therefore, to provide optimal treatment for each patient with HCC, more precise and effective biomarkers are urgently needed which could facilitate a more detailed individualized decision-making during HCC treatment, including the following; risk assessment, early cancer detection, prediction of treatment or prognostic outcome. In the blood of cancer patients, accumulating evidence about circulating tumor cells and cell-free nucleic acids has suggested their potent clinical utilities as novel biomarker. This concept, so-called "liquid biopsy" is widely known as an alternative approach to cancer tissue biopsy. This method might facilitate a more sensitive diagnosis and better decision-making by obtaining genetic and epigenetic aberrations that are closely associated with cancer initiation and progression. In this article, we review recent developments based on the available literature on both circulating tumor cells and cell-free nucleic acids in cancer patients, especially focusing on Hepatocellular carcinoma.
基金Supported by Grant from the Ministry of Education, Culture, Sports, Science, and Technology, Japan, No. 20590808The Research Committee of Intractable Diseases of the Pancreas, provided by the Ministry of Health, Labour, and Welfare Japan, No. 50253448
文摘AIM： To evaluate the efficacy of continuous regional arterial infusion therapy （CRAI） with gabexate mesilate and antibiotics for severe acute pancreatitis （SAP）. METHODS： We conducted a prospective study on patients who developed SAP with or without CRAI. Out of 18 patients fulfilled clinical diagnostic criteria for SAP in Japan, 9 patients underwent CRAI, while 9 patients underwent conventional systemic protease inhibitor and antibiotics therapy （non-CRAI）. CRAI was initiated within 72 h of the onset of pancreatitis. Gabexate mesilate （2400 mg/d） was continuously administered for 3 to 5 d. The clinical outcome including serum inflammation-related parameters were examined. RESULTS- The duration of abdominal pain in the CRAI group was 1.9 =1：0.26 d, whereas that in the non-CRAI group was 4.3 ±0.50. The duration of SIRS in the CRAI group was 2.2 ± 0.22 d, whereas that in the non- CRAI group was 3.2 ± 0.28. Abdominal pain and SIRS disappeared significantly in a short period of time after the initiation of CRAI using gabexate mesilate. The average length of hospitalization significantly differed between the CRAI and non-CRAI groups, 53.3 ± 7.9 d and 87.4± 13.9 d, respectively. During the first two weeks, levels of serum CRP and the IL6/IL10 ratio in the CRAI group tended to have a rapid decrease compared to those in the non-CRAI group. CONCLUSION： The present results suggest that CRAI using gabexate mesilate was effective against SAP.
文摘A 58-year-old Japanese man had tarry stool and severe anemia. Neither upper nor lower gastrointestinal （GI） endoscopy showed any localized lesions. Thus, the source of his GI bleeding was suspected to be in the small intestine, and he underwent peroral double-balloon enteroscopy （DBE） using EN-450T5 （Fujinon-Toshiba ES System Co., Tokyo, Japan）. There were no lesions considered to be the source of GI bleeding. After the procedure, the patient began to experience abdominal pain. Laboratory tests revealed hyperamylasemia and abdominal computed tomography revealed an inflammation of the pancreas and the peripancreas. He was thus diagnosed to have acute pancreatitis. Conservative treatments resulted in both clinical and laboratory amelioration. He had no history of alcohol ingestion, gallstone disease or pancreatitis. Magnetic resonance cholangiopancreatography demonstrated no structural alterations and no stones in the pancreatobiliary ductal system. As his abdominal pain started after the procedure, his acute pancreatitis was thus thought to have been related to the peroral DBE. This is the first reported case of acute pancreatitis probably associated with peroral DBE.
文摘AIM To investigate the clinicopathological features of the patients testing negative for high titer serum antiHelicobacter pylori(H. pylori) antibody.METHODS The antibody titers were measured using antigens derived from Japanese individuals. ^(13)C-urea breath test-positive individuals were defined as having H. pylori infection. We investigated the demographic characteristics, laboratory data, endoscopic findings including Kyoto classification of gastritis, and histology in negative-high titer patients without H. pylori eradication therapy. Kyoto classification consisted of scores for gastric atrophy, intestinal metaplasia, enlarged folds, nodularity, and redness.RESULTS Of the 136 subjects enrolled, 23(17%) had H. pylori infection. Kyoto classification had an excellent area under the receiver operating characteristics curve(0.886, 95% confidence interval: 0.803-0.968, P = 3.7 × 10^(-20)) for predicting H. pylori infection with a cutoff value of 2. Further, Kyoto classification, H. pylori density, and neutrophil activity had high accuracies(89.7%, 96.3%, and 94.1%, respectively). Kyoto classification was independent of the demographic and laboratory parameters in multivariate analysis.CONCLUSION Endoscopic Kyoto classification of gastritis is a useful predictor of H. pylori infection in negative-high titer antibody patients.
文摘Despite recent advances in surgical techniques and perioperative management, the prognosis of pancreatic cancer(PCa) remains extremely poor. To provide optimal treatment for each patient with Pca, superior biomarkers are urgently needed in all phases of management from early detection to staging, treatment monitoring, and prognosis. In the blood of patients with cancer, circulating tumor cells(CTCs) and cell-free nucleic acids(cf NAs), such as DNA, m RNA, and noncoding RNA have been recognized. In the recent years, their presence in the blood has encouraged researchers to investigate their potential use as novel blood biomarkers, and numerous studies have demonstrated their potential clinical utility as a biomarker for certain types of cancer. This concept, called "liquid biopsy" has been focused on as a less invasive, alternative approach to cancer tissue biopsy for obtaining genetic and epigenetic aberrations that contribute to oncogenesis and cancer progression. In this article, we review the available literature on CTCs and cfN As in patients with cancer, particularly focusing on PCa, and discuss future perspectives in this field.
文摘Basaloid squamous cell carcinoma （BSC） of the esophagus is a rare malignant disease. We report here a patient with recurrent esophageal BSC, who was successfully treated by systemic chemotherapy containing 5-fluorouracil （5-FU） and cisplatin （CDDP）. A 57-year-old woman was diagnosed as having SCluamous cell carcinoma of the esophagus upon endoscopic examination. Curative esophagectomy with lymph node dissection was performed under the thoracoscope. The pathological diagnosis of the surgical specimen was BSC. Five months after operation, the patient was diagnosed as having a recurrence of the BSC with metastases to the liver and spleen, and a right paraclavicular lymph node. She was given systemic chemotherapy consisting of continuous infusion of 800 mg/d of 5-FU and 3 h infusion of 20 mg/d of CDDP for 5 consecutive days every 4 wk. The metastatic lesions in the spleen and right paraclavicular lymph node disappeared, and the liver metastasis was apparently reduced in size after 2 courses of chemotherapy. The tumor regression was seen over 6 courses, with progression afterwards. Although subsequent treatment with CPT-11 and CDDP was not effective, docetaxel and vinorelbine temporarily controlled the tumor growth for 2 mo. 5-FU and CDDP combination may be useful for the patients with advanced BSC.
基金The Research Committee of Intractable Pancreatic Diseases, provided by the Ministry of Health, Labour, and Welfare, Japan, No. 50253448
文摘AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout the study. The expression of LPA receptors was confirmed by reverse-transcript polymerase chain reaction (RT-PCR). Cytosolic free calcium was measured by fluorescent calcium indicator fura-2, and the localization of NF-κB was visualized by immunofluorescent method with or without various agents, which effect cell signaling. RESULTS: Panc-1 expressed LPA receptors, LPA1, LPA2 and LPA3. LPA caused the elevation of cytosolic free calcium dose-dependently. LPA also caused the nuclear translocation of NF-κB. Cytosolic free calcium was attenuated by pertussis toxin (PTX) and U73122, an inhibitor of phospholipase C. The translocation of NF-κB was similarly attenuated by PTX and U73122, but phorbol ester, an activator of protein kinase C, alone did not translocate NF-κB. Furthermore, the translocation of NF-κB was completely blocked by Ca2+ chelator BAPTA-AM. Thapsigargin, an endoplasmic- reticulum Ca2+-ATPase pump inhibitor, also promoted the translocation of NF-κB. Staurosporine, a proteinkinase C inhibitor, attenuated translocation of NF-κB induced by LPA. CONCLUSION: These findings suggest that protein kinase C is activated endogenously in Panc-1, and protein kinase C is essential for activating NF-κB with cytosolic calcium and that LPA induces the nuclear translocation of NF-κB in Panc-1 by mobilizing cytosolic free calcium.
文摘Synovial sarcoma(SS) is genetically characterized by chromosomal translocation, which generates SYT-SSX fusion transcripts. Although SS can occur in any body part, primary gastric SS is substantially rare. Here we describe a detection of the fusion gene sequence of gastric SS in plasma cell-free DNA(cf DNA). A gastric submucosal tumor was detected in the stomach of a 27-year-old woman and diagnosed as SS. Candidate intronic primers were designed to detect the intronic fusion breakpoint and this fusion sequence was confirmed in intron 10 of SYT and intron 5 of SSX2 by genomic polymerase chain reaction(PCR) and direct sequencing. A locked nucleic acid(LNA) probe specificto the fusion sequence was designed for detecting the fusion sequence in plasma and the fusion sequence was detected in preoperative plasma cfD NA, while not detected in postoperative plasma cfD NA. This technique will be useful for monitoring translocation-derived diseases such as SS.
文摘AIM:To evaluate the chemoradiotherapy for locally advanced pancreatic cancer utilizing low dose gemcitabine as a radiation sensitizer administered twice weekly. METHODS: We performed a retrospective analysis of chemoradiotherapy utilizing gemcitabine administered twice weekly at a dose of 40 mg/m2. After that, maintenance systemic chemotherapy with gemcitabine, at a dose of 1000 mg/m2, was administered weekly for 3 wk with 1-wk rest until disease progression or unacceptable toxicity developed. RESULTS: Eighteen patients with locally advanced unresectable pancreatic cancer were enrolled. Three of those patients could not continue with the therapy; one patient had interstitial pneumonia during radiation therapy and two other patients showed liver metastasis or peritoneal metastasis during an early stage of the therapy. The median survival was 15.0 mo and the overall 1-year survival rate was 60%, while the median progression-free survival was 8.0 mo. The subgroup which showed the reduction of tumor development, more than 50% showed a tendency for a better prognosis; however, other parameters including age, gender and performance status did not correlate with survival. The median survival of the groups that died of liver metastasis and peritoneal metastasis were 13.0 mo and 27.7 mo, respectively.CONCLUSION: Chemoradiotherapy with low-dose gemcitabine administered twice weekly could be effective to patients with locally advanced pancreatic cancer; however, patients developing liver metastases had a worse prognosis. Another chemoradiotherapy strategy might be needed for those patients, such as administrating one or two cycles of chemotherapy initially, followed by chemoradiotherapy for the cases with no distant metastases.
文摘AIM: To determine the distribution of Hepatitis B virus (HBV) genotypes in Benin, and to clarify the virological characteristics of the dominant genotype.METHODS: Among 500 blood donors in Benin, 21 HBsAg-positive donors were enrolled in the study. HBV genotypes were determined by enzyme immunoassay and restriction fragment length polymorphism. Complete genome sequences were determined by PCR and direct sequencing.RESULTS: HBV genotype E (HBV/E) was detected in 20/21 (95.2%), and HBV/A in 1/21 (4.8%). From the age-specific prevalence of HBeAg to anti-HBe seroconversion (SC) in 19 HBV/E subjects, SC was estimated to occur frequently in late teens in HBV/E.The comparison of four complete HBV/E genomes from HBeAg-positive subjects in this study and five HBV/E sequences recruited from the database revealed that HBV/E was distributed throughout West Africa with very low genetic divers ity (nucleotide homology 96.7-99.2%).Based on the sequences in the basic core promoter (BCP)to precore region of the nine HBV/E isolates compared to those of the other genotypes, a nucleotide substitution in the BCP, G1757A, was observed in HBV/E.CONCLUSION: HBV/E is predominant in the Republic of Benin, and SC is estimated to occur in late teens in HBV/E. The specific nucleotide substitution G1757A in BCP, which might influence the virological characteristics,is observed in HBV/E.
文摘Objective: To Assess the correlation between different quality analysis parameters of trabecular pattern in digital panoramic radiographies and relations with forearm bone mass density (BMD) performed by DXA. Methods: The study was developed using panoramic and peripheral bone densitometry dual energy X-ray absorptiometry (DXA) of 68 patients, 9 males and 59 females (19 - 73 years old). In the panoramic radiographs, evaluation of the trabecular bone morphology through assessment of fractal dimension (FD), connectivity (C) and total number of “bright” pixels (ET) was performed. In DXA, the exam determines the bone mineral density of the forearm to identify who has a high risk of osteoporosis. Statistics analyzed the relationship of these exams and the contribution of dental radiographs in detecting patients at risk for osteoporosis. Results: The average age of subjects was 43.85. In the analysis of trabecular pattern, a significant correlation between the FD, ET and C factors in level of 5% (Pearson correlation test) was found. Correlation tests showed no significant correlation between DF and BMD. Conclusions: The analysis showed correlations with each other, detecting alterations in the trabecular pattern. It cannot be related to BMD with FD but should be taken into account that examining the bone or trabecular alveolar process, when, for example, diagnostic analysis of pre-implant bone quality, is required.
基金Supported by Japan Society for the Promotion of Science,No.21K08689,No.21K16456,No.20K09016,No.20K09084,No.19K09202 and No.19K09182.
文摘BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types.Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types.However,it remains unclear whether ANO5 acts as a plasma membrane chloride channel,and its expression and functions in gastric cancer(GC)have not been investigated.AIM To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.METHODS Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines,and changes in cell proliferation,cell cycle progression,apoptosis,and cellular movement were assessed.The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis.Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.RESULTS Reverse transcription-quantitative polymerase chain reaction(PCR)and western blotting demonstrated high ANO5 mRNA and protein expression,respectively,in NUGC4 and MKN45 cells.In these cells,ANO5 silencing inhibited cell proliferation and induced apoptosis.In addition,the knockdown of ANO5 inhibited G1-S phase progression,invasion,and migration.The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes,such as CDKN1A,CDK2/4/6,CCNE2,and E2F1,in ANO5-depleted NUGC4 cells.The expression of these genes was verified using reverse transcription-quantitative PCR.Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis.Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC(P=0
基金financially supported by the Light Metals Educational Foundation of Japan,the Ministry of Education,Culture,Sports,Science and Technology (MEXT) of Japan (No. 19H05176,21H00150)the Russian Science Foundation (No. 17-19-01311)。
文摘To have an insight into the occurrence of inverse Hall-Petch relationship in ultrafine-grained(UFG) aluminum alloys produced by severe plastic deformation(SPD),ultra-SPD(i.e.inducing several ten thousand shear strains via high-pressure torsion,HPT) followed by aging is applied to an Al-La-Ce alloy.Average nanograin sizes of 40 and 80 nm are successfully achieved together with strain-induced Lomer-Cottrell dislocation lock formation and aging-induced semi-coherent Al_(11)(La,Ce)_3 precipitation.Analysis of hardening mechanisms in this alloy compared to SPD-processed pure aluminum with micrometer grain sizes,SPD-processed Al-based alloys with submicrometer grain sizes and ultra-SPD-processed Al-Ca alloy with nanograin sizes reveals the presence of two breaks in the Hall-Petch relationship.First,a positive upbreak appears when the grain sizes decrease from micrometer to submicrometer which is due to extra hardening by solute-dislocation interactions.Second,a negative down-break and softening occur by decreasing the grain sizes from submicrometer to nanometer which is caused by weakening the dislocation hardening mechanism with minor contribution of the inverse Hall-Petch mechanism.Detailed analyses confirm that nanograin formation is not necessarily a solution for extra hardening of Al-based alloys and other accompanying strategies such as grain-boundary segregation and precipitation are required to overcome such a down-break and softening.
基金supported by JSPS KAKENHI(20K20214)to YMand a grants-in-aid of the 106th annual congress of JSS Memorial Surgical Research Fund,Tokyo,Japan to YM.
文摘Background:Although diagnostic ultrasound can non-invasively capture the image of abdominal viscera,diagnosis of the continuous ultrasound liver images to detect a liver tumor effectively and to determine whether the detected is benign or malignant is nontrivial.In order to minimize the gaps in diagnostic accuracy depending on doctor’s proficiency,we built an automated system to support the ultrasonography of liver tumors by employing deep learning technologies.Methods:We constructed a neural network model for the automated detection of tumor tissues and blood vessels from the sequential liver ultrasound images.Faster region-based convolutional neural networks(Faster R-CNN)is employed as a base model for the object detection,which can output the detection results in 4 frames per second and enable the system to be particularly suitable for the real time ultrasonography.Moreover,we proposed a new neural network architecture feeding both the current and previous images into Faster R-CNN.For training the models,intraoperative ultrasound images obtained from one hepatocellular carcinoma(HCC)patient were used.The obtained image was a multifaceted observation of the liver and includes one HCC and some blood vessels.We labeled 91 images with the help of a liver specialist.We compared the tumor detection performance of the plain Faster R-CNN model with that of the proposed model.Results:We find that both the models performed well in detecting HCC and blood vessels,after training with 400 epochs using Adam.However,the mean precision of our model reaches 0.549,which is 0.019 better than that of the plain Faster R-CNN,and the mean sensitivity of our model about HCC reaches 0.623±0.385 for 30 scenes of sequential liver ultrasound images,which is also 0.146 better than that of the plain Faster R-CNN model.Conclusions:The comparison between the proposed model and the plain Faster R-CNN model shows that we achieved better accuracy in tumor detection,in terms of the mean precision as well as the mean sensitivity,with the propo
文摘Previous clinical trials have demonstrated the efficacy of yokukansan, a traditional Japanese medicine, for the treatment of behavioral and psychological symptoms of dementia (BPSD). However, less evidence is available for the treatment of BPSD with yokukansankachimpihange (YKSCH), which consists of yokukansan and two additional herbal ingredients. The present study was conducted to investigate the efficacy and safety of YKSCH for treating BPSD in patients with Alzheimer’s disease (AD). We enrolled outpatients with mild-to-moderate AD who exhibited BPSD and obtained a Neuropsychiatric Inventory (NPI) score of >3 including subscale scores for “agitation”, “anxiety”, “irritability”, and “sleep and night-time behavior change”. A daily YKSCH dose of 7.5 g was administered for 12 weeks with concomitant administration of anti-dementia medication. BPSD was evaluated using the NPI at baseline and every 4 weeks during the intervention. We also examined apathy using the Japanese translation of the Apathy Scale, the short version of the Japanese version of the Zarit Caregiver Burden Interview, and the Modified Crichton Rating Scale for Predicting Activities of Daily Living. Cognitive dysfunction was evaluated using the Mini Mental State Examination and the AD Assessment Scale-Cognitive (Japanese version). Five participants were enrolled. The NPI total score tended to decrease between the baseline and 8-week evaluations during the YKSCH intervention (Wilcoxon signed rank test, P = 0.063). In terms of the NPI subscale scores, “apathy”, “agitation”, “delusions”, and “sleep and night-time behavior change” decreased after the intervention in those who exhibited each symptom at baseline. There were no significant differences in the other scores examined. No serious adverse events were observed. YKSCH could ameliorate BPSD in patients with mild-to-moderate AD with agitation, anxiety, irritability, and sleep and night-time behavior change, and it was well-tolerated.
文摘Background: According to the treatment guidelines for gastric cancer in Japan (3rd edition), D1 lymphadenectomy is recommended for T1a cancer (out of indication for endoscopic resection) and a group of T1b cancer (differentiated type, not larger than 1.5cm and clinically N0). D1+ lymphadenectomy is recommended for T1b cancer other than above group. D2 lymphadenectomy is for clinically N+ early gastric cancer (EGC). Methods: Consecutive 1141 resected EGC cases in our institution from January 1991 to December 2013 were analyzed. The size, depth of wall invasion, presence of ulcer, histological type and distribution of metastasis positive lymph node were evaluated. Results: There were 678 T1a and 463 T1b cancers. Lymph node metastasis positive T1a were 11 cases. All of them were undifferentiated type and the metastasis positive lymph nodes were all confined to the D1 area. Lymph node metastasis positive T1b cancer was 82 cases. Among them, 70 cases were within D1 area, 77 cases were within D1+ area and 79 cases were within D2 area. The other 3 cases had metastasis positive lymph node in beyond the D2 area. Conclusion: D1 lymphadenectomy is enough for T1a EGC that is out of indication of endoscopic resection and D1+ lymphadenectomy is reasonable for T1b EGC. These cases are good indication of laparoscopic surgery. D2 lymphadenectomy is required for T1b undifferentiated cancers which size is larger than 4 cm.
文摘The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other layer without, and (2) both NiFe layershave anisotropy normal each other. The domain wall migration and magnetization rotation processes in each of NiFe layers could be observed separately. The presence of magnetic anisotropy in the magnetic layer effectively controls the behavior of magnetic domains. Theinteraction between the two NiFe layers of the film could be observed not so strong in the present experiment.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574367)the National Basic Research Program of China(Grant Nos.2013CB921700,2013CB921904,and 2015CB921300)+2 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB07020300)The synchrotron radiation experiments have been done under the HiSOR Proposal numbers12-B-47 and 13-B-16
文摘The three-dimensional（3D） Dirac semimetals have linearly dispersive 3D Dirac nodes where the conduction band and valence band are connected. They have isolated 3D Dirac nodes in the whole Brillouin zone and can be viewed as a 3D counterpart of graphene. Recent theoretical calculations and experimental results indicate that the 3D Dirac semimetal state can be realized in a simple stoichiometric compound A3Bi（A = Na, K, Rb）. Here we report comprehensive high-resolution angle-resolved photoemission（ARPES） measurements on the two cleaved surfaces,（001） and（100）, of Na3Bi. On the（001） surface, by comparison with theoretical calculations, we provide a proper assignment of the observed bands, and in particular, pinpoint the band that is responsible for the formation of the three-dimensional Dirac cones. We observe clear evidence of 3D Dirac cones in the three-dimensional momentum space by directly measuring on the kx–ky plane and by varying the photon energy to get access to different out-of-plane kzs. In addition, we reveal new features around the Brillouin zone corners that may be related with surface reconstruction. On the（100） surface, our ARPES measurements over a large momentum space raise an issue on the selection of the basic Brillouin zone in the（100） plane. We directly observe two isolated 3D Dirac nodes on the（100） surface. We observe the signature of the Fermi-arc surface states connecting the two 3D Dirac nodes that extend to a binding energy of ~150 me V before merging into the bulk band. Our observations constitute strong evidence on the existence of the Dirac semimetal state in Na3Bi that are consistent with previous theoretical and experimental work. In addition, our results provide new information to clarify on the nature of the band that forms the3 D Dirac cones, on the possible formation of surface reconstruction of the（001） surface, and on the issue of basic Brillouin zone selection for the（100） surface.
