Spin pump and probe in lanthanum strontium manganite/platinum bilayers.

Ferromagnetic resonance driven spin pumping (FMR-SP) is a novel method to transfer spin current from the ferromagnetic (FM) layer into the adjacent normal metal (NM) layer in an FM/NM bilayer system. Consequently, the spin current could be probed in NM layer via inverse spin Hall effect (ISHE). In spite of numerous ISHE studies on FM/Pt bilayers, La0.7Sr0.3MnO3(LSMO)/Pt system has been less explored and its relevant information about interface property (characterized by spin mixing conductance) and spin-charge conversion efficiency (characterized by spin Hall angle) is a matter of importance for the possible applications of spintronic devices. In this work, the technique of FMR-SP has been applied on two series of LSMO/Pt bilayers with the thickness of each layer being varied. The thickness dependences of ISHE voltage allow to extract the values of spin mixing conductance and spin Hall angle of LSMO/Pt bilayers, which are (1.8 ± 0.4) × 1019 m-2 and (1.2 ± 0.1) % respectively. In comparison with other FM/Pt systems, LSMO/Pt has comparable spin current density and spin mixing conductance, regardless its distinct electronic structure from other ferromagnetic metals.

Influence of damping constant on inverse spin hall voltage of La0.7Sr0.3MnO3(x)/platinum bilayers.

Pure spin transport via spin pumping in the condition of ferromagnetic resonance can be transformed to charge current in the ferromagnetic/paramagnetic bilayer systems, based on inverse spin Hall effect (ISHE). Here, we explore La0.7Sr0.3MnO(x)/Pt(5.5 nm) [x = 10 to 65 nm] bilayers to investigate the influence of damping constant on spin pumping efficiency. The results show that the ISHE voltage depend on the damping constant of magnetic moment, suggesting that the precession energy tansferred to lattice/electron of normal metal is a key parameter to control the magnitude of spin current.

Endoscopic ultrasound combined with submucosal saline injection for differentiation of T1a and T1b esophageal squamous cell carcinoma: a novel technique.

Endoscopic ultrasound (EUS) is the optimum method for investigation of early esophageal squamous cell carcinoma (ESCC). However, it is difficult to substage early ESCC as T1a or T1b. The aim of this study was to improve the staging accuracy of early ESCC by using EUS combined with submucosal saline injection (SSI). The study enrolled 15 patients with suspected early ESCC who were examined by EUS and subsequently by SSI combined with EUS. The patients then underwent endoscopic or surgical resection within 10 days. The accuracy of EUS staging (alone or following SSI) was evaluated and compared with the pathological results postoperatively. No severe complications of the SSI arose. EUS plus SSI easily distinguished the mucosa from the lesion and the submucosa because of the low-echoic saline-filled cushion in the submucosa. The accuracy of SSI combined with EUS for staging T1a or T1b was 86.7 %, which was better than that using EUS alone (60.0 %).

Expression of IGF-1R in colorectal polyps and its role in colorectal carcinogenesis.

Insulin-like Growth Factor Receptor 1 (IGF-1R) may play a role in the neoplastic progression of colorectal cancer because it is related to both cellular proliferation and differentiation. The aim of this study was to further elucidate the role of IGF-1R in colorectal carcinogenesis by evaluating IGF-1R expression in different types of precancerous colorectal polyps and comparing its expression to normal mucosa and colorectal carcinoma. A total of 47 colorectal polyps and their respective adjacent normal mucosa were collected from 32 patients. In addition, 20 colorectal adenocarcinoma tissues were obtained from patients undergoing colorectal resection, and 12 normal non-malignant colorectal mucosal tissues collected from outpatients served as the control group. The pit patterns of polyps were classified by the Kudo classification scheme through magnifying chromoendoscopy. Immunohistochemistry and quantitative real-time RT-PCR were utilized for expression analysis of IGF-1R in colorectal mucosa, polyps, and adenocarcinoma tissue. The results of immunohistochemistry showed no significant differences in IGF-1R expression in inflammatory polyps compared with their surrounding normal mucosa by the Mann-Whitney U test (p=0.251); however, tubular adenoma and villous adenoma tissues exhibited significantly higher levels of IGF-1R expression (p=0.000). The results of real-time RT-PCR showed that IGF-1R was transcribed at a high level in colorectal adenomatous polyps and adenocarcinoma compared with their respective paired normal mucosa. Spearman's rank correlation two-variable analysis was used to demonstrate a significant correlation between the expression of IGF-1R and neoplastic progression from normal mucosa to adenomatous polyps and finally to colorectal cancer (r=0.574, p=0.000). This study suggests that the expression of IGF-1R correlates with the degree of carcinogenesis. In addition, these results demonstrated that there is a significant correlation between the level of IGF-1R expression and pit patterns of polyps (r=0.432, p=0.002). Thus, IGF-1R might be a factor in the morphological change of colorectal mucosal crypts, and it may play an important role in the growth and malignant transformation of precancerous polyps. These results suggest that IGF-1R can be considered a biomarker for the stage and risk of carcinogenesis during neoplastic initiation and progression along the colorectal normal mucosa-polyp-cancer sequence. Inhibitors of IGF-1R are not only a promising targeted anticancer strategy, but also a possible option for the chemoprevention of colorectal cancer.

Complications of high intensity focused ultrasound for patients with hepatocellular carcinoma.

UNLABELLED: High intensity focused ultrasound (HIFU) is a noninvasive treatment modality that induces complete coagulative necrosis of a deep tumor through the intact skin. This study was conducted to analyze and evaluate the complications of HIFU for the treatments of hepatocellular carcinoma. A total of 59 patients with hepatocellular carcinoma, with a total of 72 lessions were enrolled in this study. Tumor size ranged from 2.5 to 14.0 cm in diameter, with a mean diameter of 7.6 cm. All patients had accepted HIFU treatment, and the median number of HIFU sessions was 1.32 per patient. RESULTS: The common complications from HIFU therapy were skin burns of various grades (eight cases of grade 1 skin burns, 48 of grade 2, three cases of 3), and pain in the treatment regions (15 cases of mild pain, 37 cases of moderate pain, 7 cased of severe pain). Other systemic complications were relatively rare and included fever (5 cases), hypertension (8 cases), supraventricular tachycardia (3 cases), mild impairment of hepatic function (48 cases), and mild mpairment of renal function (2 cases). Local damage consisted of acute cholecystitis (2 cases), hematuria (6 cases ), cholangiectasis (5 cases), light pericardial effusion (2 cases), impairment of peripheral nerves (10 cases), pleural effusion in the right thorax (3 cases), and impairment of vertebral column (1 case). No gastric or intestinal tract perforation, big vessel rupture, or hepatic rupture occurred. CONCLUSIONS: HIFU is a minimally invasive treatment for patients with hepatocellular carcinoma; however, there are some systemic and local complications that should be taken into consideration in evaluating HIFU for therapeutic use.

[Effects of clonidine on experimental stomach ulcer in rats].

Clonidine 2 mg/kg ig inhibited the rat gastric ulcers induced by pyloric ligation, stress and indomethacin by 71%, 77% and 82%, respectively. Clonidine 2 mg/kg ig tended to accelerate the healing of gastric ulcer induced by acetic acid, and the healing rate was 61%. Clonidine decreased the secretion of gastric acid and pepsin, and increased the release of gastric barrier mucus. These actions may contribute to its protective effect against ulceration.