Current antibiotic prophylaxis in pancreatoduodenectomy in Japan

Background/Purpose

The aim of this study was to investigate the current use of antibiotic prophylaxis (AP) in association with pancreatoduodenectomy (PD) in Japan, and to determine its surgical implications.

Methods

We surveyed 2331 patients who underwent PD for treatment of disease in the periampullary region. Data, obtained during the period January 2002 through December 2003, from 111 major surgical services associated with the Japanese Society for Pancreatic Surgery, were analyzed with regard to patient characteristics, preoperative complications, AP, and postoperative morbidities.

Results

Eighty-five (78.7%) of the 108 eligible institutions chose a first- or second-generation cephalosporin for AP, given for a mean duration of 4.3 days. At all but 1 institution, the first dose was administered prior to surgical incision of the skin. At 42% of the institutions, an additional antibiotic was administered during surgery. The overall rate of wound infection was 6.8% of the 2266 patients for whom data were available. Preoperative jaundice was found in 55.3% of these 2266 patients, and 92.6% of these jaundiced patients were suffering from preoperative infections. In addition, those with preoperative infections were also diagnosed as having biliary infections. The number of patients with preoperative jaundice in combination with preoperative infections was significantly related to the rate of postoperative morbidity (P < 0.0001).

Conclusions

Administration of AP in association with PD in Japan seems appropriate. Icteric patients with biliary infections are at high risk for postoperative morbidities and need careful monitoring after surgery.     

Fibrolamellar hepatocellular carcinoma: report of a case

We report a case of fibrolamellar hepatocellular carcinoma, which occurred in a 58-year-old man with normal liver function. Preoperative ultrasonography, computed tomography and magnetic resonance imaging depicted a large tumor in the left lateral segment, which was compatible with the typical radiological features of fibrolamellar hepatocellular carcinoma. He underwent left lobectomy and no lymphadenopathy or distant metastasis was demonstrated. Macroscopic findings of the resected liver demonstrated a well-defined whitish-yellow tumor with a central scar. Microscopic findings of the tumor showed cords of tumor cells, which were surrounded by abundant collagenous fibrous tissue arranged in a lamellar distribution. He has been doing well for approximately one year since the surgery without any signs of recurrence. In addition, we discuss the clinicopathological features of fibrolamellar hepatocellular carcinoma based on a review of 22 Japanese patients who have been previously reported.     

Endogenous adenosine inhibits platelet aggregation during myocardial ischemia in dogs.

The goal of this study was to clarify that blockade of adenosine receptors during myocardial ischemia causes further reductions in coronary blood flow due to platelet aggregation. Coronary perfusion pressure in 47 open-chest dogs was reduced such that coronary blood flow decreased to one fifth of the control value; thereafter, coronary perfusion pressure was maintained at the low levels. During hypoperfusion, coronary flow was kept low but constant with a massive release of adenosine. When 8-phenyltheophylline, an adenosine receptor antagonist, was infused during coronary hypoperfusion, coronary blood flow (18 +/- 2 ml/100 g/min) gradually decreased at 5-10 minutes of ischemia and reached almost zero at 20 minutes. Three minutes after the onset of ischemia, before further reduction of coronary flow, the microscopic examination revealed the existence of thromboembolization in the small coronary arteries, and the number of platelets in the regional coronary venous blood were significantly decreased, indicating that a further reduction of coronary flow due to treatment with 8-phenyltheophylline is attributed to thromboembolism caused by platelet aggregations. This reduction of coronary flow and formation of thromboembolism were inhibited by the treatments with dibutyryl cAMP, forskolin, and yohimbine, indicating that this thromboembolization during a lack of adenosine activity is due to platelet aggregation and that platelet aggregation caused by 8-phenyltheophylline is triggered by stimulation of alpha 2-adrenoceptors by released norepinephrine during ischemia. We demonstrate that adenosine, generated endogenously in response to ischemia, inhibits platelet aggregation. The finding that adenosine is not merely a vasodilator but that it also regulates thrombosis has major implications for designing new strategies of myocardial salvage.     

Opening of the adenosine triphosphate-sensitive potassium channel attenuates cardiac remodeling induced by long-term inhibition of nitric oxide synthesis: role of 70-kDa S6 kinase and extracellular signal-regulated kinase

OBJECTIVES: We examined whether the adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channel openers (KCOs) block myocardial hypertrophy and whether the 70-kDa S6 kinase (p70S6K) or extracellular signal-regulated kinase (ERK)-dependent pathway is involved. BACKGROUND: Long-term inhibition of nitric oxide (NO) synthesis induces cardiac hypertrophy independent of blood pressure, by increasing protein synthesis in vivo. The KCOs attenuate calcium overload and confer cardioprotection against ischemic stress, thereby preventing myocardial remodeling. METHODS: Twelve Wistar-Kyoto rat groups underwent eight weeks of the drug treatment in combination with the NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME), the inactive isomer D(omega)-nitro-L-arginine methyl ester, KCOs (nicorandil, 3 and 10 mg/kg per day, or JTV-506, 0.3 mg/kg per day), or the K(ATP) channel blocker glibenclamide. The L-NAME was also used with hydralazine, the p70S6K inhibitor rapamycin, or the mitogen-activated protein kinase inhibitor PD98059. Finally, the left ventricular weight (LVW) to body weight (BW) ratio was quantified, followed by histologic examination and kinase assay. RESULTS: The L-NAME increased blood pressure and LVW/BW, as compared with the control agent. The KCOs and hydralazine equally cancelled the increase in blood pressure, whereas only KCOs blocked the increase in LVW/BW and myocardial hypertrophy induced by L-NAME. The L-NAME group showed both p70S6K and ERK activation in the myocardium (2.3-fold and 2.0-fold increases, respectively), as compared with the control group, which was not reversed by hydralazine. Selective inhibition of either p70S6K or ERK blocked myocardial hypertrophy. The KCOs prevented the increase in activity only of p70S6K. Glibenclamide reversed the effect of nicorandil in the presence of L-NAME. CONCLUSIONS: The KCOs modulate p70S6K, not ERK, to attenuate myocardial hypertrophy induced by long-term inhibition of NO synthesis in vivo.     

Folate receptor allows cells to grow in low concentrations of 5-methyltetrahydrofolate.

The folate receptor mediates the uptake of 5-methyltetrahydrofolate in certain cultured cells by a process called potocytosis. When these cells are grown in physiological concentrations of folate, the receptor increases the efficiency of vitamin uptake by 30-fold. We now show that PAM 212 cells, a mouse keratinocyte cell line, are unable to grow in 1 nM 5-methyltetrahydrofolate unless they express a functional folate receptor. These results suggest that under certain conditions, tissue cells in the body may depend on the folate receptor to obtain enough 5-methyltetrahydrofolate for growth.     

Atorvastatin slows the progression of cardiac remodeling in mice with pressure overload and inhibits epidermal growth factor receptor activation.

The aim of this study was to investigate whether atorvastatin inhibits epidermal growth factor receptor (EGFR) activation in cardiomyocytes in vitro and slows the progression of cardiac remodeling induced by pressure overload in mice. Either atorvastatin (5 mg/kg/day) or vehicle was orally administered to male C57BL/6J mice with transverse aortic constriction (TAC). Physiological parameters were obtained by echocardiography or left ventricular (LV) catheterization, and morphological and molecular parameters of the heart were also examined. Furthermore, cultured neonatal rat cardiomyocytes were studied to clarify the underlying mechanisms. Four weeks after TAC, atorvastatin reduced the heart/body weight and lung/body weight ratios (8.69+/-0.38 to 6.45+/-0.31 mg/g (p<0.001) and 10.89+/-0.68 to 6.61+/-0.39 mg/g (p<0.01) in TAC mice with and without atorvastatin, respectively). Decrease of LV end-diastolic pressure and the time constant of relaxation, increased fractional shortening, downregulation of a disintegrin and metalloproteinase (ADAM)12, ADAM17 and heparin-binding epidermal growth factor genes, and reduction of the activity of EGFR and extracellular signal-regulated kinase (ERK) were observed in the atorvastatin group. Phenylephrine-induced protein synthesis, phosphorylation of EGFR, and activation of ERK in neonatal rat cardiomyocytes were all inhibited by atorvastatin. These findings indicated that atorvastatin ameliorates cardiac remodeling in mice with pressure overload, and its actions are associated with inhibition of the EGFR signaling pathway.     

NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modifies the effects of alcohol consumption on risk for hypertension in middle-aged Japanese men.

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity in the Japanese population, and the ND2-237Met genotype may exert antiatherogenic effects. To investigate whether ND2-237 Leu/Met polymorphism is associated with risk of hypertension, we conducted a cross-sectional study of 398 Japanese male subjects. The frequency of hypertension was significantly higher in ND2-237Leu genotypic men than in ND2-237Met genotypic men. On analysis of covariance, the interaction between ND2-237 Leu/Met polymorphism and habitual drinking was significantly associated with both systolic blood pressure and diastolic blood pressure. Multiple logistic regression analysis revealed that the ND2-237Met genotype, particularly in younger subjects (age <60 years), had a lower odds ratio for hypertension than the ND2-237Leu genotype. Moreover, the association of ND2-237 Leu/Met polymorphism with hypertension may depend on the frequency of alcohol consumption. The odds ratio for hypertension was significantly higher in daily drinkers with ND2-237Leu when compared with non- or ex-drinkers with ND2-237Leu. However, the association between the ND2-237Met genotype and hypertension may not depend on the frequency of alcohol consumption. The present results suggest that ND2-237 Leu/Met polymorphism is associated with hypertension and that modification of hypertension risk is dependent on alcohol consumption in middle-aged Japanese men.     

A New Ultrasonographic “Fluttering Sign” for Hepatic Hemangioma

The aim of the study described here was to clarify the diagnostic value of the fluttering sign, a new sign that characterizes hepatic hemangiomas in gray-scale ultrasonography (US). It refers to a phenomenon in which the speckled echogenicity inside the hemangioma changes continuously and seems to be moving. A total of 172 hemangiomas diagnosed with contrast-enhanced US were evaluated. The fluttering sign was found in 123 of 172 hemangiomas (71.5%). Its prevalence was significantly higher than that of the marginal strong echo (89/172, 51.7%, p < 0.001), posterior acoustic enhancement (103/172, 59.9%, p = 0.031) and chameleon sign (100/172, 58.1%, p = 0.013). In addition, the fluttering sign was observed significantly more frequently in mixed or hypo-echoic tumors than in hyper-echoic tumors (p < 0.001), relatively large tumors (p < 0.001) and tumors that were less than 5 cm from the body surface (p = 0.015). The fluttering sign in gray-scale US has great potential to be a new complementary sign for the diagnosis of hemangioma.