Strain difference in transgene-induced tumorigenesis and suppressive effect of ionizing radiation

Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53^+/−, p53^−/−) and Hd-rR HNI hybrid (p53^+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53^+/− fish than in p53^−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.     

Open channel block of NMDA receptors by conformationally restricted analogs of milnacipran and their protective effect against NMDA-induced neurotoxicity

We investigated the blocking effect of the conformationally restricted analogs of milnacipran on NMDA receptors by recording the whole-cell currents of Xenopus oocytes injected with rat brain mRNA and the single channel currents of cultured hippocampal neurons under voltage-clamp conditions. Their protective effect against excitotoxicity was also investigated on cultured cortex neurons. All conformationally restricted analogs examined blocked activated NMDA receptors, though their structures were quite different from known NMDA receptor blockers. The analogs with a (1S, 2R, 1'S)-configuration such as PPDC ((1S, 2R)-1-phenyl-2[(S)-1-aminopropyl]-N,N-diethylcyclopropanecarboxamide+ ++) had lower IC50 values than those with other configurations. The empirical Hill coefficients for each compound were close to unity, indicating a 1:1 stoichiometry for the block. PPDC decreased the maximum responses to both N-methyl D-aspartate (NMDA) and glycine without altering their dissociation constants. The blocking effect was enhanced on hyperpolarization. PPDC had no effects on other glutamate receptor subtypes (AMPA, kainate, and metabotropic glutamate receptors) or other neurotransmitter receptors (GABA(A), 5HT2C, and AChM1 receptors) produced by the oocytes. PPDC decreased the mean open time of NMDA receptors without decreasing their elementary conductance. The microscopic blocking rate constant was 2.8x10(7) M(-1)s(-1). The macroscopic unblocking rate constant of PPDC was much faster than that of MK-801. Only the analogs with the (1S, 2R, 1'S)-configuration protected the cultures against NMDA-induced neurotoxicity, though they failed to protect against kainate-induced neurotoxicity. These results show that conformationally restricted analogs, at least PPDC, selectively blocked open channels of NMDA receptors.     

Preoperative portal vein embolization improves prognosis after right hepatectomy for hepatocellular carcinoma in patients with impaired hepatic function

BACKGROUND: Percutaneous transhepatic portal vein embolization (PTPE) increases the safety of subsequent major hepatectomy. The aim of this study was to determine the effect of PTPE on long-term prognosis after hepatectomy in patients with hepatocellular carcinoma (HCC). METHODS: Seventy-one patients with HCC underwent right hepatectomy between 1984 and 1998. Preoperative PTPE was performed in 33 patients (group 1) and was not used in 38 patients (group 2). Outcome after operation was compared between the groups. The patients were further divided according to the median tumour diameter (cut-off 6 cm) and indocyanine green retention rate at 15 min (ICGR15) (cut-off 13 per cent). RESULTS: The cumulative survival rate was significantly higher in group 1 than in group 2 in patients with an ICGR15 of at least 13 per cent. Tumour-free survival rates were similar in both groups. Of patients with tumour recurrence after right hepatectomy, those in group 1 were more frequently subjected to further treatment. CONCLUSION: Preoperative PTPE improves the prognosis after right hepatectomy for HCC in patients with impaired hepatic function, although it does not prevent tumour recurrence.     

The Simultaneous Onset of Pancreatitis and Colitis as Immune-related Adverse Events in a Patient Receiving Nivolumab Treatment for Renal Cell Carcinoma

Immune checkpoint inhibitors (ICIs), which have anti-tumor effects, are currently approved for treatment of several kinds of advanced malignancies. However, with their increasing use, a variety of immune-related adverse events (irAEs) in administered patients have been reported. We herein report a rare case of the simultaneous onset of acute pancreatitis and colitis as irAEs during nivolumab treatment given to a patient with renal cell carcinoma, who then shown marked improvement with corticosteroid therapy.     

Dietary Gamma-Aminobutyric Acid (GABA) Induces Satiation by Enhancing the Postprandial Activation of Vagal Afferent Nerves

Gamma-aminobutyric acid (GABA) is present in the mammalian brain as the main inhibitory neurotransmitter and in foods. It is widely used as a supplement that regulates brain function through stress-reducing and sleep-enhancing effects. However, its underlying mechanisms remain poorly understood, as it is reportedly unable to cross the blood–brain barrier. Here, we explored whether a single peroral administration of GABA affects feeding behavior as an evaluation of brain function and the involvement of vagal afferent nerves. Peroral GABA at 20 and 200 mg/kg immediately before refeeding suppressed short-term food intake without aversive behaviors in mice. However, GABA administration 30 min before refeeding demonstrated no effects. A rise in circulating GABA concentrations by the peroral administration of 200 mg/kg GABA was similar to that by the intraperitoneal injection of 20 mg/kg GABA, which did not alter feeding. The feeding suppression by peroral GABA was blunted by the denervation of vagal afferents. Unexpectedly, peroral GABA alone did not alter vagal afferent activities histologically. The coadministration of a liquid diet and GABA potentiated the postprandial activation of vagal afferents, thereby enhancing postprandial satiation. In conclusion, dietary GABA activates vagal afferents in collaboration with meals or meal-evoked factors and regulates brain function including feeding behavior.     

The Japanese experience with sirolimus-eluting stent implantation in the infarct-related artery: Five years of observation from the J-PMS study

BackgroundLong-term outcome and safety concerns regarding drug-eluting stents (DES) for acute myocardial infarction (AMI) treatment is still debated.Methods and resultsWe analyzed data from 1937 patients with complete 5-year follow-up (94.5%) from a multicenter registry of sirolimus-eluting stents (J-PMS). The patients were divided into 2 groups: AMI (n = 133) and non-AMI (n = 1804) by clinical presentation of index procedure, and compared the outcomes. At 5-year follow-up, there were no significant differences in major adverse cardiac events (MACE), death, MI, or stent thrombosis between the groups. However, target vessel related events (TVF; revascularization, cardiac death, MI, thrombosis) were higher in the non-AMI group (p = 0.03). In the early phase (0–6 months), MACE and death/MI were higher in the AMI group (6.0% vs. 3.0%; p = 0.02 and 6.8% vs. 2.1%; p < 0.001). However, in the late phase (6–60 months), there was a difference in TVF between the 2 groups, with a steady increase in the non-AMI group (p = 0.03). Over 60% of patients with AMIs were started on dual antiplatelet therapy after stent implantation or on the same day. However, dual anti-platelet therapy duration was similar (867 ± 18 days in the AMI and 727 ± 57 days in the non-AMI group, p = 0.5). Frequency of bleeding was similar.ConclusionFive-year observation of AMI treatment using drug-eluting stent compared with non-AMI has no clinical disadvantage.     

Serum markers of liver fibrosis and histologic severity of fibrosis in resected liver

BACKGROUND/AIMS: Serum concentrations of the 7S fragment of type IV collagen (7S collagen), amino-terminal propeptide of type III procollagen (PIIIP), and hyaluronic acid (HA) have been reported to serve as serologic markers of liver fibrosis in hepatitis and cirrhosis. We investigated whether these fibrosis markers reliably reflect histologic changes in the livers of patients with hepatocellular carcinoma. METHODOLOGY: Subjects included 165 patients undergoing liver resection for hepatocellular carcinoma. Most were seropositive for chronic hepatitis B or C. Histopathologic changes in liver tissue resected with the tumor were scored according to Knodell's histologic activity index. Serum was sampled for assays shortly before surgery. RESULTS: Significant correlations were found between hepatitis activity score and 7S collagen, PIIIP, and HA. Concentrations of 7S collagen differed significantly between activity grades, but differences were not significant for PIIIP or HA. Significant correlations were found between fibrosis staging score and all these three markers. When patients were divided according to activity grade, 7S collagen showed stronger correlation with fibrosis staging score than did PIIIP or HA. CONCLUSIONS: The 7S collagen fragment correlated more strongly than PIIIP or HA with stage and activity grade in patients with hepatocellular carcinoma. However, overlapping of results between histologically defined groups appeared to limit clinical diagnostic usefulness of all markers in individual patients.     

Expression of bile duct-type cytokeratin in noncancerous hepatocytes in patients with hepatitis B virus-related hepatocellular carcinoma

BACKGROUND/AIMS: Hepatocytes express bile duct-type cytokeratin in various conditions, which indicates the presence of hepatic progenitor cells. We investigated the clinical significance of cytokeratin 7 expression in the noncancerous hepatitis tissue in patients with hepatitis B virus-related hepatocellular carcinoma. METHODOLOGY: Specimens were obtained from 24 patients who underwent liver resection for hepatitis B virus-related hepatocellular carcinoma. The hepatocytes in the noncancerous hepatic tissue were examined immunohistochemically using monoclonal antibodies against cytokeratin 7. RESULTS: Expression of cytokeratin 7 was observed in 9 patients (group 1). Group 2 consisted of the other 15 patients. Serum transaminases were significantly higher in group 1 than in group 2. The percentage of patients with moderate or severe active hepatitis, the percentage of patients with cirrhosis, and the percentage of patients with portal invasion were significantly higher in group 1 than in group 2. The tumor-free survival rate was significantly lower in group 1 than in group 2. CONCLUSIONS: The expression of cytokeratin 7 in noncancerous hepatic tissue is closely related to the severity of and duration of chronic hepatitis B. The expression of cytokeratin 7 in the noncancerous hepatic tissue is a possible risk factor for recurrence after resection of hepatitis B virus-related hepatocellular carcinoma.     

Impact of air-conditioner outlet layout on the upward airflow induced by forced air warming in operating rooms

BackgroundPreviously, we found that an upward air current in the head area, induced by forced air warming (FAW), was completely counteracted by downward laminar airflow. However, this study did not include any consideration of the air-conditioner outlet layout (ACOL); hence, its impact remains unclear.MethodsThis study was performed in 2 operating rooms (ORs)—ISO classes 5 and 6, which are denoted as OR-5 and OR-6, respectively. Both ORs have distinct ACOLs. The cleanliness, or the number or ratio of shifting artificial particles was evaluated.ResultsDuring the first 5 minutes after particles generation, significantly more particles shifted into the surgical field in OR-5 when compared to OR-6 (13,587 [4,341-15,913] and 106 [41-338] particles/cubic foot, P < .0001). Notably, FAW did not increase the number of shifting particles in OR-6. The laminar airflow system fully counteracted the upward airflow caused by FAW in OR-6, where the ACOL covered the operating bed. However, this did not occur in OR-5, where the ACOL did not fully cover the operating bed.ConclusionsRegardless of cleanliness ability of OR, an ACOL that fully covers the operating bed can prevent upward airflow in the head area and reduce the number of artificial particles shifting into the surgical field, which are typically caused by FAW.     

Bilateral subchondral insufficiency fracture of the femoral head after renal transplantation: a case report

This report describes the case of a 47-year-old woman who was found to have subchondral insufficiency fractures in both femoral heads after renal transplantation. Initially, plain radiographs showed no obvious changes, but magnetic resonance imaging (MRI) revealed an irregular, discontinuous, low-intensity band on the T1-weighted image of both hips. The patient was treated nonsurgically. Ten months after onset, the pain in both hips disappeared, and plain radiographs and MRI showed no abnormalities. Subchondral insufficiency fracture should be considered in the diagnosis of patients who have hip pain after renal transplantation.