Calculation Method of the Optimum Configurations of the Extended Surfaces with Simultaneous Conductive, Convective and Radiative Heat Transfer in Heat Exchanger

A simultaneous conductive, convective and radiative heat transfer in the extended surface systems of longitudinally finned cylinders and circumferentially finned cylinders is treated analytically, by taking the radiative interaction into consideration. A procedure to determine the optimum configurations of extended surfaces is examined for the various kinds of combinations of six heat transfer parameters from the viewpoint of saving fin material. It is found that if the radiative interaction is not taken into consideration, wrong results are included. Instead of using the complex optimization algorithm, a graphical expression is adopted to show the numerical coefficients and indices in the formulas which give the optimum dimensionless fin height and the minimum fin volume

A Free Jejunal Reconstruction Following the Failure of an Initial Esophageal Reconstruction with Colic Pedicle - Report of a Case

A 58-year-old man who had undergone a gastrectomy for early cancer was admitted with a diagnosis of esophageal cancer. A subtotal esophagectomy with a reconstruction using the right hemicolon was performed. However, the reconstructed colon became necrotic and, as a result, the necrotic section of the colon was removed and the temporary esophagectomy and colostomy were made. A repeat reconstruction using free jejunal graft with micro vascular anastomoses was thus performed and the results were satisfactory

Can POSSUM, a Scoring System for Perioperative Surgical Risk, Predict Postoperative Clinical Course ?

POSSUM, a Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity, is a scoring system which assesses perioperative surgical risks (Copeland GP et al.: Br J Surg, 1991, Vol 78, 356-360). The POSSUM scoring system consists of two categories of assessment to assess the risk of surgery. A 12-factor (age, cardiac status, pulse rate, systolic blood pressure, respiratory status, Glasgow Coma Score, serum concentration of urea, potassium and sodium, hemoglobin concentration, white cell count and findings on electrocardiography) and 4-grade physiological score (PS) were developed. This was combined with a 6-factor (type of surgical procedure, number of procedures, blood loss, peritoneal soiling, presence of malignancy and mode of surgery) and 4-grade operative severity score (OSS). The present paper attempts to validate it retrospectively. Postoperative hospitalization period and duration of antibiotics administration were both significantly correlated with OSS, but not with PS. These results suggest that the POSSUM scoring system is useful for predicting the postoperative clinical course.</p

Can POSSUM, a Scoring System for Perioperative Surgical Risk, Predict Postoperative Clinical Course ?

POSSUM, a Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity, is a scoring system which assesses perioperative surgical risks (Copeland GP et al.: Br J Surg, 1991, Vol 78, 356-360). The POSSUM scoring system consists of two categories of assessment to assess the risk of surgery. A 12-factor (age, cardiac status, pulse rate, systolic blood pressure, respiratory status, Glasgow Coma Score, serum concentration of urea, potassium and sodium, hemoglobin concentration, white cell count and findings on electrocardiography) and 4-grade physiological score (PS) were developed. This was combined with a 6-factor (type of surgical procedure, number of procedures, blood loss, peritoneal soiling, presence of malignancy and mode of surgery) and 4-grade operative severity score (OSS). The present paper attempts to validate it retrospectively. Postoperative hospitalization period and duration of antibiotics administration were both significantly correlated with OSS, but not with PS. These results suggest that the POSSUM scoring system is useful for predicting the postoperative clinical course.</p

The expression of transporter OATP2/OATP8 decreases in undetectable hepatocellular carcinoma by Gd-EOB-MRI in the explanted cirrhotic liver

Purpose: The aim of this study is to evaluate the detectability of hepatocellular carcinoma (HCC) in the explanted cirrhotic liver using gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-MRI) and the degree of organic anion transporter OATP2/OATP8 (OATP1B1/1B3) HCC which could not be preoperatively detected by multi-detector computed tomography (MD-CT) and Gd-EOB-MRI. Methods: Eleven patients (HBV 3, HCV 7, nonBnonC 1) out of 145 recipients of liver transplantation were analyzed. The detectability by each imaging modality and the expression of OATP2/OATP8 of HCC were analyzed using the whole liver thin sliced histological and immunohistochemical examination retrospectively. Results: The imaging examination detected 17 lesions of HCC by MDCT and/or Gd-EOB-MRI. Only one lesion detected by Gd-EOB-MRI had well differentiated and minute (7 mm) HCC. However, the histological examination revealed newly 11 lesions and one false-positive lesion of HCC in the explanted livers. The median diameter of the preoperatively undetectable HCC by imaging was 8 mm (2-12). The histological characteristic of the preoperatively undetectable HCC was well differentiated HCC (10/11). The accuracy rate in MDCT and Gd-EOB-MRI was 53.6 % (15/28) and 57.1 % (16/28). The rate of positive predictive value in MDCT and Gd-EOB-MRI was 93.7 % (15/16) and 94.2 % (16/17), respectively. The expression of OATP2/OATP8 in the preoperatively undetectable HCC was negative in nine lesions, was weak positive in two lesions. Conclusions: The detectability of Gd-EOB-MRI is almost equal to MDCT in a cirrhotic liver. Small HCCs were difficult to detect even with Gd-EOB-MRI. The transporter of OATP2/OATP8 was less expressed in the preoperatively undetectable HCCs