Suturing is an essential surgical skill for clinical residents. However, acquiring on-the-job training and practice for this skill is becoming difficult due to the growing awareness of patients' rights and safety. Thus, training clinicians get most of their suturing practice on simulators that use artificial compounds such as urethane that generally do not adequately represent ‘real-life’ tactile sensation. Since 2011, we have therefore conducted an annual surgical skill-up seminar using swine skin, stomach, intestine, and blood vessels for clinical residents of Showa University Northern Yokohama Hospital. This seminar is held on an autumn Saturday afternoon at Terumo Medical Pranex^® in Nakai-cho, Ashigarakami-gun, Kanagawa, in collaboration with the Department of Medical Education, Digestive Disease Center and other surgical departments. We have thus far trained 92 participants (52 clinical residents and 40 surgical physicians) in total in the following areas: skin suturing, tracheotomy, laparoscopic cholecystectomy, organ anastomosis (stomach to small intestine), and vascular anastomosis. A post-practice unsigned questionnaire revealed an affirmative self-assessment rating of approximately 95% regarding the seminar contents. Most participants were satisfied with the group setting, but not satisfied with the 3.5-hour training time. Although hosting this wet-lab training seminar using biological models requires a significant budget and manpower, it has successfully provided a valuable learning opportunity on basic surgical skills for clinical residents.

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A small subset of carcinomas of various origins are associated with high numbers of tumor-infiltrating neutrophils (TINs). Here, we examined the characteristics of non-small-cell pulmonary carcinomas with high numbers of TINs, and their relationship with lymph node (LN) metastasis. The study included 100 patients diagnosed and treated for primary pulmonary carcinoma at Showa University Northern Yokohama Hospital from 2011 to 2012. We histopathologically defined tumors with > 10 neutrophils per high-power field as neutrophilrich. Among the 100 patients, 40 were classed as having neutrophilrich pulmonary cancer (NRPC), and tissue samples from these patients were prepared for further examination. Comparison of the clinicopathological factors (age, gender, tumor size, histological type, and grade) in NRPC cases with or without LN metastasis showed that none of the above factors was significantly correlated with LN metastasis. Immunohistochemical analysis of two cytokines that play a major role in granulopoiesis, granulocyte-colony stimulating factor (G-CSF) and macrophage-CSF (M-CSF), revealed that the expression of M-CSF, but not G-CSF, was significantly correlated with LN metastasis. Furthermore, coexpression of M-CSF and the M-CSF receptor was significantly correlated with LN metastasis, but coexpression of G-CSF and the G-CSF receptor did not show such a correlation. These findings indicate that M-CSF-producing NRPCs show a significantly high lymph node metastasis potential.

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Intracholecystic papillary-tubular neoplasm (ICPN) has recently been proposed as a new disease concept in the classification of gallbladder tumors. ICPN is defined as a papillary or polypoid glandular neoplasm forming a localized, non-invasive mass (≥ 1cm) in the gallbladder. We analyzed the clinicopathological characteristics of ICPN. Resected gallbladder cancer specimens from 57 patients were classified as ICPN or non-ICPN and clinicopathological characteristics were compared. ICPN cell characteristics were also analyzed using immunostaining and genetic analysis. Twenty-three cases were classified as ICPN and 34 as non-ICPN. In the ICPN and non-ICPN groups, mean ages were 69 and 74 years, male:female ratios were 14:9 and 15:19, mean tumor diameters were 2.8 and 2.6cm, invasion depths were Tis+T1/T2+T3 in 14/9 cases and 13/21 cases, lymph node metastases were present in 6% and 43%, distant metastases in 0% and 6% and 3-year survival rates were 91% and 52%, respectively. Significant intergroup differences were seen in lymph node metastases and the 3-year survival rate. ICPN cell lineage was biliary-type in 13 cases, gastric-type in 8 and intestinal-type in 2. This proportion differs from that of pancreatic intraductal papillary mucinous neoplasm (IPMN), in which gastric- and intestinal-type are more common. KRAS gene mutations were only seen in 1 of 13 ICPN cases. ICPN is frequently seen in gallbladder cancer, showing similar pathology to pancreatic IPMN, which is considered to have a relatively good prognosis among pancreatic cancers. However, ICPN cell characteristics are not necessarily identical to those of pancreatic IPMN.

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Abstract: Malignant hyperthermia (MH) is a potentially fatal pharmacogenetic disorder triggered by exposure to commonly used volatile anesthetics. Pharmacological and genetic analyses implicated the type 1 of ryanodine receptor (RyR1) /Ca²⁺ release channel as the main candidate gene for causing MH. Genetic diagnosis of MH was proposed to replace conventional methods using biopsied muscle samples that are painful for patients and require skillful diagnosticians to interpret. However, more than 250 RyR1 gene variants have now been reported in MH-susceptible patients, although most have yet to be associated with functional abnormalities using exogenous constructs of these mutants expressed in living cells. To directly compare the pharmacological characteristics of some of the MH-related RyR1 mutants, we have established doxycycline -inducible cell lines expressing two of the unconfirmed rabbit RyR1 mutants, Q156K or R534H (corresponding to the Q155K or R533H mutations in human RyR1 reported in MH patients in Japan) and a confirmed mutant, R164C RyR1 (corresponding to the R163C mutation in human). The caffeine sensitivity of Q156K-expressing cells was remarkably enhanced compared to wild-type RyR1 and similarly to previously reported levels for R164C-expressing cells, while that of the R534H mutants was not different from wild-type cells. The resting cytosolic Ca²⁺ concentrations of cell lines expressing Q156K or R164C were much higher than those expressing R534H or wild-type RyR1. These results indicated that the RyR1 gene mutation causing the Q156K phenotype (Q155K in human) is potentially susceptible to MH, and that screening for this mutation could be useful for the noninvasive genetic diagnosis of MH in humans.

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Colorectal flat-elevated neoplasms can be classified into small-flat adenoma and laterally spreading tumors (LSTs), which can then be sub-categorized into granular-type (LST-G) and nongranular-type (LST-NG) LSTs with possible biological differences between them. We evaluated clinicopathological features and KRAS / BRAF mutations in 24 LST-Gs and 57 LST-NGs. PCR-based pyrosequencing assays were used to determine the presence of activating mutations in codons 12 and 13 of KRAS and in codon 600 of BRAF. Significant differences between LST-Gs and LST-NGs were observed in tumor size (30mm vs. 15mm, P < 0.0001) and the frequency of KRAS mutations (75%, 18/24 vs. 5%, 3/57, P < 0.0001). For LST-NGs, the histological grade was increased with an increase in the tumor size. The frequency of submucosal cancer (SM-ca) was also higher in tumors of at least 20mm than in tumors smaller than 20mm (P < 0.05). In contrast, there was no indication of a size-dependent increase in the histological grade. No significant difference in the frequency of KRAS mutation in LST-Gs and LST-NGs was related to tumor size. Two subtypes of LSTs were observed to have different clinicopathological and molecular characteristics. These findings suggest that different molecular mechanisms could exist in these subtypes of colorectal flat-type neoplasms.

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Fucoidan, a natural sulfated polysaccharide found in the extracellular matrix of brown algae, is rich in L-fucose and sulfate. Fucoidan has a variety of biological actions, including anti-oxidative, anti-coagulative, anti-cancer, and anti-inflammatory activity. However, the cellular molecular mechanism underlying the anti-inflammatory effects of fucoidan remains poorly understood. Rheumatoid arthritis (RA) is a chronic inflammatory disease that causes synovitis and progressive joint destruction. Interleukin (IL) -1β, one of the important mediators involved in the pathogenesis of RA, is known to activate various intracellular signaling pathways. Therefore, in the present study we investigated the inhibitory effects of fucoidan on IL-1β-induced inflammation in human synovial (SW982) cells. SW982 cells were pretreated with fucoidan (100µg/mL) for 1h before cotreatment with 5ng/mL IL-1β plus fucoidan for periods ranging from 20min to 24h. Levels of the proinflammatory mediators IL-6, tumor necrosis factor-α, and cyclooxygenase-2 were then determined. We also assayed translocation of nuclear factor (NF) -κB into the nucleus and activation of mitogen-activated protein kinase (MAPK). Significant increases in the production of proinflammatory mediators were observed from 6 to 24h of IL-1β treatment. The translocation of NF-κB into the nucleus peaked after approximately 6h incubation. After 20min incubation, IL-1β activated c-jun N-terminal kinase and p38 MAPK in SW982 cells. This effect was ameliorated by the coincubation of cells with fucoidan. These results suggest that fucoidan exerts its anti-inflammatory effect by regulating the gene expression of proinflammatory mediators by suppressing the activity of transcription factors and MAPK. Thus, fucoidan may have therapeutic potential for the treatment of RA.

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We investigated hip joint destruction in patients with rheumatoid arthritis before and after the availability of methotrexate and biological disease-modifying anti-rheumatic drugs (DMARDs) in Japan. A total of 35 patients with 45 diseased joints underwent total hip arthroplasty from 1995 to 1999 (Group A: 21 hips in 15 patients) and from 2006 to 2010 (Group B: 24 hips in 20 patients). We monitored the oral administration of therapeutic drugs and prednisolone, measured preoperative C-reactive protein (CRP) levels, estimated the Larsen grade and bone defects of the acetabulum floor using simple X-ray images, and calculated the bone defect rate of the femoral head. The intake of preoperative oral prednisolone was significantly less in Group B than in Group A (P < 0.05), as were preoperative CRP levels (P < 0.05). There was no difference in Larsen grade between the groups. Type III (combined type) bone defects of a large size in the acetabulum base were observed in the hip joints of 12 hips in Group A (57.1%) and 10 hips in Group B (41.7%), and the mean rate of bone defects in the femoral head was 26.7% in Group A and 33.7% in Group B. These findings indicated that the recent introduction of effective medical treatment has decreased the number of patients with large bone defects in the acetabulum. Furthermore, the number of patients subjected to total hip arthroplasty for rheumatoid arthritis accompanied by severe hip joint destruction has decreased. However, the number of patients who underwent total hip arthroplasty was slightly higher in this study, indicating that even if the disease activity of rheumatoid arthritis is suppressed, joint destruction may continue in the hip joint of patients with previously recognized mild joint destruction.

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The osteoclast is a multinucleated giant cell differentiated from monocyte macrophages that has an important role in bone resorption. Several studies have reported a relationship between tea consumption and decreased risk of bone fracture. Matrix metalloproteinases (MMPs) play an important role in the degeneration of bone and cartilage matrix. Regulation of osteoclast activity is essential in the treatment of bone disease. Moreover, MMPs are associated with osteoclast formation and differentiation. We have reported previously that (-) -epigallocatechin-3-gallate (EGCG) inhibits MMP-2 and MMP-9 expression and activity. However, the effects of EGCG on osteoclasts and other MMPs are not clear. Therefore, in the present study we examined whether EGCG affects MMP expression, as well as osteoclast formation, differentiation and activity, in vitro. We used bone marrow cells from the femur and tibial bones of male ddY mice. Bone marrow cells were cultured in the presence of 1∼100µM EGCG for 6 or 8 days. EGCG decreased the number of mature osteoclasts, as determined by tartrate-resistant acid phosphatase staining. Concentrations as low as 1µM EGCG clearly inhibited the differentiation of osteoclasts from bone marrow cells. EGCG also inhibited the number of osteoclasts with an actin-ring, as determined by rhodamine phalloidin staining, as well as osteoclast activity, as determined by the pit formation assay. Furthermore, EGCG concentration-dependently decreased MMP-9 and membrane type 1-MMP mRNA expression in mouse osteoclasts. However, EGCG had no changing on mRNA levels of tissue inhibitor of metalloprotease (TIMP)-1 and TIMP-3. Together, the results suggest that EGCG may be a suitable agent or lead compound for the development of treatments for bone resorption diseases associated with MMPs.

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Hepatitis viruses are causative agents for chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. However these viruses are also associated with lymphoproliferative disorders (LPDs), such as essential mixed cryoglobulinemia and B-cell non-Hodgkin's lymphoma. Indeed, hepatitis C virus infection has been confirmed to be associated with LPDs, but the pathogenic mechanism remains unclear. In this study, we investigated the relationship between hepatitis B virus (HBV) infection and LPDs in 84 patients with chronic hepatitis B (CH-B). LPD markers, such as cryoglobulinemia, high levels of rheumatoid factor (RF), hypocomplementemia, and B cell clonality, were measured and analyzed along with viral factors. Results showed that high levels of RF were observed in 39.5% of patients with CH-B. These high RF levels were not associated with abnormal levels of other LPD markers, but only with the presence of HBV DNA in the sera of these patients. Undergoing therapy with nucleotide analogues was also associated with high RF. In two patients with CH-B, decreasing levels of RF were observed during antiviral therapy. In conclusion, high RF levels are associated with HBV viremia in patients with CH-B. HBV infection also plays an important role in the genesis of LPDs in patients with viral hepatitis.

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Background: In the present study we investigated autonomic dysfunction using hemodynamics and analysis of heart rate variability (HRV) following ambulatory blood pressure monitoring (APBM) in patients with neurally mediated reflex syncope (NMRS). In addition, we evaluated the usefulness of ABPM for diagnosing NMRS. Methods: In all, 88 consecutive patients with syncope and 12 controls (Group C) were subjected to a head-up tilt (HUT) test (80°, 30 min). If no syncope or presyncope occurred, the HUT test was repeated in the patient group following drug loading (ATP, isoproterenol, and/or isosorbide dinitrate). Results: Forty patients had a positive HUT test, with or without drug loading (Group P) ; the HUT test was negative in 48 patients, even after drug loading. Average daytime systolic and diastolic blood pressure (SBP and DBP, respectively) was significantly lower in Group P than in Group C (P = 0.042 and P = 0.047, respectively). The average standard deviation of SBP at night (SD-SBP_Night) was significantly higher in Group P than in Group C (P = 0.004). HRV analysis revealed a significantly higher daytime high-frequency component in Group P than in Group C (P = 0.041). Conclusion: The results of the present study suggest that lower daytime blood pressure and a larger SD-SBP_Night, as determined by ABPM, are associated with vagal nerve hyperactivity and sympathetic hypoactivity in patients with NMRS. Thus, an inadequate circadian rhythm in blood pressure variation, as identified by ABPM, may be useful for the diagnosis of NMRS.

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To evaluate the effects of low-dose intravitreal injections of bevacizumab (IVB) in retinopathy of prematurity (ROP). A total of 14 eyes of 7 patients received IVB (0.25mg/eye) for treatment of ROP from April 2011 to June 2012 at Showa University. This retrospective case series included the patients who were followed up for at least 5 months after IVB. Ten eyes of five patients were included in the analysis. The mean gestational age and birth weight were 24.6 (range: 22-26) weeks and 770 grams (range: 505-1055), respectively. Eight eyes of four patients with stage 3 ROP with plus disease were laser treated, and two eyes of one patient were treated with aggressive posterior ROP (AP-ROP) without laser use. All of the eyes received only a single injection of IVB. The mean injection age and body weight were 37.2 (range: 34-39) weeks of postconceptional age and 2073 grams (range: 1400-2995). Of the eight eyes with stage 3 ROP with plus disease, six eyes (four patients) regressed after IVB treatment. Two eyes (two patients) were treated with vitrectomy after IVB. The AP-ROP regressed after IVB and a subsequent laser treatment. IVB was performed as a salvage therapy, and low-dose IVB was effective for promoting the regression of ROP. However, IVB increased fibrotic traction in some eyes. In the BEAT-ROP study, a dosage of 0.625mg IVB was used as a monotherapy; however, intravitreally injected bevacizumab can escape to the systemic circulation. Thus, the use of a lower dosage of IVB for ROP in combination with laser therapy appears to be efficacious until the optimal dosage can be established.

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