Detection of coronary plaque by computed tomography with a novel plaque analysis system, 'Plaque Map', and comparison with intravascular ultrasound and angioscopy.

BACKGROUND: Previous reports suggest that plaque may be characterized by the computed tomography (CT) number, but there is not a comprehensive method for evaluating the gray-scale CT image of the coronary artery obtained by multi-detector row CT (MDCT). METHODS AND RESULTS: Forty-five patients with acute coronary syndrome (ACS) underwent MDCT either 3-4 weeks after the onset of acute myocardial infarction (n=24) or within 1 week after percutaneous coronary intervention in patients with unstable angina (UA; n=21). The cross-sections obtained at intervals of 5 mm were converted to numerical data and a 'plaque map' was drawn using the color-based isometric line method and bird's eye view. 'Plaque map' was compared with the findings of intravascular ultrasound (IVUS) and angioscopy. Of 662 slices of 78 vessels, soft, intermediate or calcified plaque was detected in 144, 134, and 84 slices, respectively. Compared with IVUS, the sensitivities were 92%, 87%, and 89%, respectively, and compared with angioscopy, sensitivity was 80% and specificity was 87%. CONCLUSIONS: MDCT with the 'Plaque Map' system can noninvasively characterize plaque in patients with ACS.     

A case of pulmonary arteriovenous fistula associated with multiple hepatic arterioportal shunts]

We report a case of pulmonary arteriovenous fistula with multiple hepatic arterioportal shunts. A 23-year-old man was admitted for evaluation of a nodular shadow in the right lower lung field. Chest CT showed a homogeneous and well-defined nodular shadow in the right S7. 3-dimensional CT revealed an arteriovenous fistula composed of a feeding artery and a draining vein in the right S7. Abdominal enhanced CT revealed a diffusely heterogeneous pattern in the liver parenchyma and the portal vein staining diffusely at the late arterial phase. We diagnosed pulmonary arteriovenous fistula associated with multiple hepatic arterioportal shunts. Pulmonary arteriovenous fistula is often associated with hereditary hemorrhagic telangiectasia (HHT). This case did not meet the criteria for HHT at this time. However, we could not exclude the possibility of HHT because clinical manifestations of HHT become apparent after 40 years old among 10% of patients. The natural history and treatment of HHT are not clear. We concluded that we should be careful to detect possible manifestations as HHT when we diagnose and follow up patients with pulmonary arteriovenous fistula.     

Histamine synthesis is required for granule maturation in murine mast cells

Mast cells are the major sources of histamine, which is released in response to immunological stimulations. The synthesis of histamine is catalyzed by histidine decarboxylase (HDC). Previous studies have shown that Hdc^?/? mast cells exhibit aberrant granule morphology with severely decreased granule content. Here, we investigated whether the histamine synthesized in mast cells regulates the granule maturation of murine mast cells. Several genes, including those encoding granule proteases and enzymes involved in heparin biosynthesis, were downregulated in Hdc^?/? peritoneal mast cells. Impaired granule maturation was also found in Hdc^?/? BM‐derived cultured mast cells when they were cocultured with fibroblasts in the presence of c‐kit ligand. Exogenous application of histamine and several H₄ receptor agonists restored the granule maturation of Hdc^?/? cultured mast cells. However, the maturation of granules was largely normal in Hrh4^?/? peritoneal mast cells. Depletion of cellular histamine with tetrabenazine, an inhibitor of vesicular monoamine transporter‐2, did not affect granule maturation. In vivo experiments with mast cell deficient Kit^W/Kit^W‐v mice indicated that the expression of the Hdc gene in mast cells is required for granule maturation. These results suggest that histamine promotes granule maturation in mast cells and acts as an proinflammatory mediator.     

Longitudinal evaluation of local muscle conditions in a rat model of gastrocnemius muscle injury using an in vivo imaging system

This study aimed to evaluate the time course of local changes during the acute phase of gastrocnemius muscle strain, in a rat model, using an in vivo imaging system. Thirty‐eight, 8‐week‐old Sprague‐Dawley male rats were used in our study. Experimental injury of the right gastrocnemius muscle was achieved using the drop‐mass method. After inducing muscle injury, a liposomally formulated indocyanine green derivative (LP‐iDOPE, 7 mg/kg) was injected intraperitoneally. We evaluated the muscle injuries using in vivo imaging, histological examinations, and enzyme‐linked immunosorbent assays. The fluorescence peaked approximately 18 h after the injury, and decreased thereafter. Histological examinations revealed that repair of the injured tissue occurred between 18 and 24 h after injury. Quantitative analyses for various cytokines demonstrated significant elevations of interleukin‐6 and tumor necrosis factor‐α at 3 and 18 h post‐injury, respectively. The time course of fluorescence intensity, measured using in vivo imaging, demonstrated that the changes in cytokine levels and histopathologic characteristics were consistent. Specifically, these changes reached peaked 18 h post‐injury, followed by trends toward recovery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1034–1038, 2015.     

Applicability of the Milan Criteria for Determining Liver Transplantation as a First-Line Treatment for Hepatocellular Carcinoma

Background To determine whether or not the Milan criteria (MC) should be used to determine the applicability of liver transplantation (LT) as a first-line treatment for patients with cirrhosis with hepatocellular carcinoma (HCC) who are able to endure hepatectomy.Methods Retrospective analysis of 82 patients with cirrhosis with HCC who were treated by hepatectomy without LT at our institution between 1990 and 2003.Results Of these 82 patients, 48 met the MC. Proportional hazard regression analyses to determine the independent prognostic factors for postoperative cumulative patient and disease-free survival showed that meeting the MC is the strongest prognostic factor for both patient and disease-free survival. The cumulative patient and disease-free survival rates were 76.7% and 28.9%, respectively, at 5 years in patients who met the MC. The cumulative disease-free survival was markedly inferior to those in previously reported series of LT for HCC who met the MC, but the cumulative patient survival was comparable to those in the previously reported series. A comparison of cumulative postoperative survival between patients who met the MC and fulfilled all five factors listed below and patients who met the MC but did not fulfill any of the five factors demonstrated that the latter patients showed statistically significantly worse postoperative patient survival than the former. The five factors included: Model for End-Stage Liver Disease score <10, indocyanine green retention rate at 15 minutes <20%, absence of microscopic fibrous capsular invasion and microscopic intrahepatic metastases, and earlier grade (T1 or T2) of American Joint Committee on Cancer tumor classification.Conclusions The MC should not be used to determine the applicability of LT as a first-line treatment for patients with HCC considered able to endure hepatectomy. However, modifying MC with some clinicopathological factors could satisfy the appropriate criteria for applying LT as a first-line treatment for these patients.     

The Evaluation of Duct-to-mucosal Pancreaticojejunostomy in pancreaticoduodenectomy

This study was conducted to examine the efficacy of duct-to-mucosal pancreaticojejunostomy compared with external stented pancreaticojejunostomy in prevention of several complications, retrospectively. Seventy-six patients with pancreatic head resection (59 male; median age, 60.1 years) underwent pancreaticoduodenectomy at the Second Department of Surgery, Wakayama Medical University, School of Medicine, Wakayama, Japan, between January 1, 1994, and March 31, 2002. In early postoperative status, the incidence of pancreatic fistula by duct-to-mucosal anastomosis (n = 45) was similar to that by external stent (n = 31); soft pancreas is a risk factor of pancreatic fistula compared with hard pancreas (p < 0.05). During the late postoperative period, however, no patients with duct-to-mucosal anastomosis showed pancreatic duct dilatation by computed tomography (CT). At the same time, 58.8% of patients with external stent followed by CT showed pancreatic duct dilatation (p < 0.01). The duct-to-mucosal anastomosis was more effective pancreaticojejunostomy than the external stent in terms of prevention of pancreatic duct dilatation, and it should be the surgical procedure of choice in pancreaticoduodenectomy.     

Half clamping of the infrahepatic inferior vena cava reduces bleeding during a hepatectomy by decreasing the central venous pressure

Background and aims  Bleeding from the hepatic vein is closely related to central venous pressure (CVP). To evaluate the effect of low central venous pressure during a hepatectomy, the infrahepatic inferior vena cava (IVC) was half clamped. Patients and methods  Between 2006 and 2007, 20 patients undergoing major hepatectomy with the IVC half clamping (half-clamping group) were compared with 58 patients undergoing hepatectomy without IVC half clamping between 2003 and 2005 (control group). The types of liver resection, amount of blood loss during the hepatectomy, volume of blood transfusion, length of hospital stay, and complications were compared between the two groups. Results  In the half-clamping group, blood loss was decreased in comparison to the control group (p = 0.041) and the suprahepatic CVP was low (2.4 ± 1.8 mmHg; p = 0.0002). The diameter at the root of the right hepatic vein was reduced in comparison to before clamping (5.8 ± 1.6 mm; p < 0.001). There were no complications of half clamping on any hemodynamic and blood electrolytic parameters. Conclusion  Using the half clamping technique of the IVC, intra-operative CVP was maintained below 3 mmHg without any side effects, and the low CVP significantly reduced the bleeding from hepatic veins during a major hepatectomy.     

Retroportal Hepaticojejunostomy for Extended Resection of Hilar Bile Ducts

High hepatic duct resection sometimes is unavoidable in achieving curative resection of hilar cholangiocarcinoma, as tumor cells can extend further than expected along the bile ducts from the macroscopically evident cancer. In patients undergoing left hemihepatectomy with caudate lobectomy whose bile duct must be severed at the subsegmental bile duct levels, the orifices of the posterior bile ducts would lie behind the right portal vein. Conventional hepaticojejunostomy would be risky in such cases because an anastomosis performed in the usual manner would be subjected to strain. Instead, between 2002 and 2004, three patients underwent retroportal hepaticojejunostomy using a jejunal limb mobilized and positioned behind the hepatoduodenal ligament. Primary tumors were classified as type IV in the Bismuth–Corlette classification. Tension-free hepaticojejunal anastomosis was performed successfully in all three patients; insufficiency of the hepaticojejunostomy did not develop. Neither early nor late complications directly related to this method occurred. Retroportal hepaticojejunostomy, thus, permits more peripheral resection of the hepatic duct while providing a sufficient operative field for safe, tension-free anastomosis. This technique is very useful for patients undergoing left hemihepatectomy requiring high hilar resection of the bile duct.