Secondary solid tumors after allogeneic hematopoietic SCT in Japan

To evaluate the incidence and risk factors for secondary solid tumors in Japan after allogeneic hematopoietic SCT (allo-HSCT), 2062 patients who had received allo-HSCT between 1984 and 2005 were retrospectively analyzed. Twenty-eight patients who developed 30 solid tumors were identified a median of 5.6 years after transplantation. The risk for developing tumors was 2.16-fold higher than that of the age- and sex-adjusted general population. The cumulative incidence of solid tumors at 10 years after allo-HSCT was 2.4%. The risk was significantly higher for tumors of the skin, oral cavity and esophagus (standard incidental ratio 40.23, 35.25 and 10.73, respectively). No increase in gastric, colon or lung cancer, despite being the most prevalent neoplasm in the Japanese, was observed. In multivariate analysis, occurrence of chronic GVHD and malignant lymphoma as a primary disease was associated with a higher risk for developing solid tumors. Eighteen patients are still alive, and their 5-year probability of survival since diagnosis of solid tumors is 59.7%. Our data suggest that the incidence and risk factors of secondary solid tumors in Japanese allo-HSCT recipients are comparable to those reported in Western countries and emphasize that the early detection of solid tumors has a crucial role in improving OS.

High Resolution Plan View Imaging of Clean and Au Deposited Si(111) Surfaces

High resolution plan view images of clean and Au deposited Si(111) surfaces are presented. Corner holes and small holes between dimers of the DAS model of the 7×7 structure were clearly resolved. In the case of the Si (111) 5×1-Au structure the 5 times period fringes did not show fine details.

[Laparoscopic surgery for esophageal achalasia]

Laparoscopic Heller myotomy and Dor fundoplication (LHD) were superior to pneumatic dilatation in terms of the treatment of esophageal achalasia according to 2 prospective randomized studies. Therefore, LHD is recommended. Some key points should be considered when performing LHD. First, the short gastric arteries and veins should be carefully divided so as not to injure the spleen. Second, during the Heller myotomy, the mucosa of the esophagus and stomach should not be injured because an inappropriate myotomy will not alleviate dysphagia, and intensive myotomy is recommended with care. When the mucosa is injured, the surgeon should repair the mucosa using absorbable sutures and the intracorporeal knot tying technique. Third, a tight fundoplication can cause dysphagia postoperatively. The endoscope should be inserted into the stomach and the fundoplication should be performed loosely.

Esophagectomy for cancer: clinical concerns support centralizing operations within the larger hospitals

Esophagectomy needs experienced surgical techniques and a well-trained perioperative care team. There are now many reports that the mortality rate after esophagectomy is higher in those hospitals with a low volume of esophagectomy and/or low surgeon's volume. The purpose of this study is to decide the respective numbers of esophagectomy operations per year to define low-volume and high-volume hospitals in Japan. If medical policy aims to further reduce mortality and morbidity associated with esophagectomy, then esophagectomy operations should be further centralized, away from low-volume hospitals, into high-volume hospitals. The Japanese Association for Thoracic Surgery has accumulated the surgical outcomes from 31 380 esophagectomy operations, registered from 709 institutes during the period from 2001 to 2006. These institutes are here classified into six groups according to the number of esophagectomy operations per year as 4 or less, 5-9, 10-19, 20-39, 40-79, and 80 or more. Using a statistical model-selection procedure by information criteria, these six groups are then classified into three categories as low-volume, medium-volume, and as high-volume hospitals. Among the 31 380 patients registered, overall, 390 patients (1.2%) died within 30 days, and 1187 patients (3.8%) died during the primary hospital stay. The odds ratio of the greatest volume group to the minimum volume group was 0.307 for the 30-day mortality rate, and 0.288 for the in-hospital mortality rate. For both the 30-day mortality rate and the in-hospital mortality rate, a hospital with less than five esophagectomy operations per year was classified as a low-volume hospital. A hospital with 40 or more esophagectomy operations per year was classified as a high-volume hospital. Concerning the number of esophagectomy operations performed per year in Japan, low-volume hospitals are defined as those where esophagectomy is performed less than five times per year, and high-volume hospitals are defined as those where esophagectomy is performed 40 or more times per year. If medical policy in Japan aims to further decrease the mortality after esophagectomy, then esophagectomy operations should be limited in these identified low-volume hospitals.

Functions of glutamate transporters in cerebellar Purkinje cell synapses

Glutamate transporters play a critical role in the maintenance of low extracellular concentrations of glutamate, which prevents the overactivation of post-synaptic glutamate receptors. Four distinct glutamate transporters, GLAST/EAAT1, GLT-1/EAAT2, EAAC1/EAAT3 and EAAT4, are distributed in the molecular layer of the cerebellum, especially near glutamatergic synapses in Purkinje cells (PCs). This review summarizes the current knowledge about the differential roles of these transporters at excitatory synapses of PCs. Data come predominantly from electrophysiological experiments in mutant mice that are deficient in each of these transporter genes. GLAST expressed in Bergmann glia contributes to the clearing of the majority of glutamate that floods out of the synaptic cleft immediately after transmitter release from the climbing fibre (CF) and parallel fibre (PF) terminals. It is indispensable to maintain a one-to-one relationship in synaptic transmission at the CF synapses by preventing transcellular glutamate spillover. GLT-1 plays a similar but minor role in the uptake of glutamate as GLAST. Although the loss of neither GLAST nor GLT-1 affects cerebellar morphology, the deletion of both GLAST and GLT-1 genes causes the death of the mutant animal and hinders the folium formation of the cerebellum. EAAT4 removes the low concentrations of glutamate that escape from uptake by glial transporters, preventing the transmitter from spilling over into neighbouring synapses. It also regulates the activation of metabotropic glutamate receptor 1 (mGluR1) in perisynaptic regions at PF synapses, which in turn affects mGluR1-mediated events including slow EPSCs and long-term depression. No change in synaptic function is detected in mice that are deficient in EAAC1.