Src tyrosine kinase is the trigger but not the mediator of ischemic preconditioning

The signal cascade that triggers and mediates ischemic preconditioning (IPC) remains unclear. The present study investigated the role of the Src family of tyrosine kinases in IPC. Isolated and buffer-perfused rat hearts underwent IPC with three cycles of 5-min ischemia and 5-min reperfusion, followed by 30-min ischemia and 120-min reperfusion. The Src tyrosine kinase family-selective inhibitor PP1 was administered between 45 and 30 min before ischemia (early PP1 treatment) or for 15 min before IPC [early PP1-preconditioning (PC) treatment]. PP1 was also administered for 5 min before the sustained ischemia (late PP1 treatment) or after IPC (late PP1-PC treatment). Src kinase was activated after 30 min of ischemia in both the membrane and cytosolic fractions. Src kinase was also activated by IPC but was attenuated after the sustained ischemia. Early and late PP1 treatment inhibited Src activation after the sustained ischemia and reduced infarct size. Early PP1-PC inhibited Src activation after IPC but not after the sustained ischemia and blocked cardioprotection afforded by IPC. Late PP1-PC treatment abrogated IPC-induced activation of Src and protein kinase C (PKC)-epsilon in the membrane but not in the cytosolic fraction. This treatment modality abrogated Src activation after the sustained ischemia and failed to block cardioprotection afforded by IPC. These results suggest that Src kinase activation mediates ischemic injury but triggers IPC in the position either upstream of or parallel to membrane-associated PKC-epsilon.

Successful prevention of recurrent ventricular fibrillation by intravenous isoproterenol in a patient with Brugada syndrome

Intravenous administration of isoproterenol restored the ST-segment configuration to nearly normal in the right precordial leads and completely prevented spontaneous VF attacks in a patient with Brugada syndrome. The formation of a Brugada-type ECG has been attributed to the transmural dispersion of repolarization of the right ventricular epicardium and related to modulation of the autonomic nervous system. Our case may provide clues to the pathophysiological mechanism of this syndrome.

Mac-1 (CD11b/CD18) and intercellular adhesion molecule-1 in ischemia-reperfusion injury of rat liver

The chronological expression (over 24 h) of two adhesion molecules [intercellular adhesion molecule-1 (ICAM-1) and CD11b/CD18 (Mac-1)] and the extent of liver damage, including injury to sinusoidal endothelial cells (SECs) and hepatocyte apoptosis, were investigated under two conditions of rat liver ischemia-reperfusion (I/R) injury: reversible (30 min) and fatal I/R (60 min). The chronological profiles of upregulation of ICAM-1 on hepatocytes and Mac-1 showed changes in parallel with the other liver damage parameters, and the extent of upregulation and various parameters of liver injury were more advanced in the 60-min I/R group. Paradoxically, the degree of ICAM-1 upregulation of SECs decreased significantly in the 60-min I/R group vs. the 30-min I/R group. Repression of hepatocyte apoptosis by administration of the caspase inhibitor ZVAD-fmk resulted in attenuation of neutrophil infiltration and liver injury. These findings indicate that 1) neutrophil infiltration is involved in the development of liver I/R injury; 2) interaction between ICAM-1 on SECs and Mac-1 on neutrophils is not an essential step for neutrophil transmigration through the endothelial layer because SECs, specifically, were impaired in the early stages of liver I/R injury; 3) the role of ICAM-1 and Mac-1 is to adhere neutrophils firmly to hepatocytes and activate neutrophils; and 4) excessive parenchymal apoptosis may be the signal for the neutrophil-induced inflammatory and necrotic reaction.

Hepatocyte growth factor promotes epithelial morphogenesis and occludin linkage to the cytoskeleton in cultured retinal pigment epithelial cells

BACKGROUND

Although hepatocyte growth factor (HGF) is also known as scatter factor, it induces epithelial morphogenesis in cultured bovine retinal pigment epithelial (RPE) cells. To elucidate the mechanism of epithelial morphogenesis, we investigated the influence of HGF on occludin, a major component of tight junctions.

METHODS

RPE cells were plated on collagen type 1-coated chamber slides or dishes, 20 ng/ml HGF was added and the cells were incubated for 1 week. Cells were harvested at several time-points, and occludin expression was examined by immunohistochemistry. Detergent extraction protocols to identify the intensity of occludin linkage to the cytoskeleton were also used. Occludin expression was determined semiquantitatively by Western blotting.

RESULTS

Fluorescence microscopy revealed that HGF treatment increased the levels of insoluble occludin at the cell borders after detergent extraction. These level of insoluble occludin and the associated epithelial morphology were maintained for more than 3 weeks after withdrawal of HGF, whereas cells not treated with HGF had a fibroblastic appearance. Western blotting also showed that insoluble occludin was more abundant in HGF-treated cells. Furthermore, immunoreactive bands of insoluble occludin were somewhat larger than those of soluble occludin, suggesting that insoluble occludin may be modified in comparison to soluble occludin.

CONCLUSION

Our results suggest that HGF promotes linkage of occludin to the cytoskeleton. HGF may become a therapeutic candidate in physiological recovery of RPE cells and in preparation of RPE monolayers for transplantation.

Effect of cicletanine on the nitric oxide pathway in human umbilical vein endothelial cells

The purpose of this study was to evaluate the effects of cicletanine, a slightly diuretic antihypertensive drug, on human vascular endothelial cells with regard to nitric oxide, intracellular calcium concentration ([Ca2+]i), cyclic nucleotide, inositol 1,4,5-trisphosphate (IP3), and prostacyclin generation. Primary cultured human umbilical vein endothelial cells were used in this study. [Ca2+]i was measured by fura-2/AM. Cyclic adenosine monophosphate (AMP), cyclic guanosine monophosphate (GMP), IP3, and prostacyclin were measured by radioimmunoassay. Nitric oxide was measured by the Griess method. Cicletanine had no effect on [Ca2+]i. Cicletanine (10(-6)-10(-4) M) increased cyclic GMP but decreased prostacyclin generation. Cicletanine had no stimulating effect on cyclic AMP or IP3 generation. IP3 increased 45Ca release from storage sites. Cicletanine decreased prostacyclin generation via increase in cyclic GMP. Cicletanine had no stimulating effect on nitrogen oxides for 2 h after incubation but increased it after 3-24 h. Pretreatment with L-N(G)-monomethyl-arginine (L-NMMA) prevented this increase. The inhibitory effect of L-NMMA was prevented by pretreatment with L-arginine. These results indicate that nitric oxide and cyclic GMP may contribute to the antihypertensive action of cicletanine.

Selective versus total drainage for biliary obstruction in the hepatic hilus: an experimental study

BACKGROUND

Controversy exists as to whether selective biliary drainage (SBD) or total biliary drainage (TBD) is preferable as a preoperative procedure before extended hemihepatectomy for hilar cholangiocarcinoma, especially with regard to the functional reserve of the future remnant liver.

METHODS

SBD or TBD was performed after 1 week of total biliary obstruction in rats. In SBD, the biliary trees of the left lobes (approximately 70% of the liver) were kept obstructed, whereas the right lobes were drained selectively. Mitochondrial function and microsomal cytochrome content were examined before and 1, 2, and 4 weeks after drainage.

RESULTS

The right lobes weighed significantly more after SBD than after TBD. There were no significant differences in mitochondrial function between the two groups. The microsomal cytochrome content per milligram of microsomal protein significantly decreased 1 week after biliary obstruction and then recovered to a similar extent after SBD and TBD in the right lobes. However, the total microsomal cytochrome content (nanomoles per 100 g body weight) and the overall rate of mitochondrial adenosine triphosphate synthesis (mmoles per minute per 100 g of body weight) in the right lobes 4 weeks after SBD were significantly greater than those after TBD.

CONCLUSIONS

SBD is superior to TBD with regard to the functional reserve of the future remnant liver.

Insulin-like growth factor 1 prevents neuronal cell death and paraplegia in the rabbit model of spinal cord ischemia

OBJECTIVE

Insulin-like growth factor 1 has been shown to be cytoprotective against ischemia-reperfusion injury in various organs. However, spinal cord protection by insulin-like growth factor 1 has not been tested. We have therefore examined the effect of insulin-like growth factor 1 on neuronal cell death and motor function after spinal cord ischemia.

METHODS

Japanese white rabbits were subjected to spinal cord ischemia by clamping the abdominal aorta for 15 minutes. Insulin-like growth factor 1 (0.3 mg/kg) at a dose equipotent to insulin (0.3 IU/kg) in lowering blood glucose level or the control (phosphate-buffered saline solution as a vehicle) was administered intravenously 30 minutes before the aortic clamp.

RESULTS

Hind-limb motor function had recovered normally 48 hours after the operation in all the rabbits (n = 8) treated with insulin-like growth factor 1. In contrast, all the control-treated (n = 8) and all but one of the insulin-treated (n = 6) rabbits had deteriorated to paraplegia by 48 hours after the operation. Histopathologic sections in the involved spinal cord segment showed that a significantly (P <.0001) greater number of motor neuron cells were preserved in the rabbits treated with insulin-like growth factor 1 (17.9 +/- 4.8 per section) than in those treated with the control (8.0 +/- 2.1). Although insulin was equipotent to insulin-like growth factor 1 in preserving the number of motor neuron cells (18.5 +/- 2.7), the percentage of motor neuron cells positive for terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick-end labeling were significantly (P <.01) smaller in the rabbits treated with insulin-like growth factor 1 (6.0 +/- 4.6) compared with those treated with the control (54.6 +/- 33.8) and insulin (26.2 +/- 11.7). Immunohistochemical studies revealed that insulin-like growth factor 1 increased expression of the antiapoptotic Bcl-xL protein and inhibited expression of the proapoptotic Bax protein in motor neuron cells 24 and 48 hours after the operation. In contrast, expression of only Bax was increased after the operation in other groups of rabbits subjected to spinal cord ischemia.

CONCLUSIONS

These results suggest that insulin-like growth factor 1, but not insulin with a conventional dose, protects motor neuron cells from ischemic spinal cord injury associated with differential regulation of Bcl-xL and Bax protein.

Value of lipiodol computed tomography and digital subtraction angiography in the era of helical biphasic computed tomography as preoperative assessment of hepatocellular carcinoma

OBJECTIVE

To compare the diagnostic accuracies of Lipiodol computed tomography (CT) and helical biphasic CT as preoperative imaging modalities for hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

Lipiodol CT after digital subtraction angiography has long been used as a highly sensitive imaging modality for HCC. The recent advent of helical CT has allowed scanning the entire liver during both the arterial and portal venous phase of contrast enhancement.

METHODS

The authors analyzed data from 164 patients who underwent hepatic resection for HCC to calculate the sensitivity and specificity of these modalities. Findings of intraoperative ultrasonography followed by histologic confirmation were set as the gold standard.

RESULTS

Although sensitivity decreased with both modalities as tumors became small and well differentiated, helical CT showed a higher sensitivity than Lipiodol CT in detecting well-differentiated HCC nodules smaller than 2 cm. In contrast, Lipiodol CT was superior to helical CT for the detection of small but moderately to poorly differentiated nodules. The overall sensitivity of helical CT was higher than that of Lipiodol CT. These findings suggest that helical CT is superior in delineating early HCC, whereas Lipiodol CT is specific to the detection of intrahepatic metastases. In terms of specificity, helical CT was superior to Lipiodol CT.

CONCLUSIONS

Helical CT and Lipiodol CT are complementary modalities. At present, helical biphasic CT does not obviate the need for invasive techniques such as angiography and Lipiodol CT as preoperative examinations for HCC.

Experimental study of pulmonary artery infusion with cisplatin in a solitary pulmonary tumor model using a rat colorectal adenocarcinoma cell line

OBJECTIVES

We assessed a tumor model prepared by open lung injection to study metastatic lung tumors, and evaluated the efficacy of pulmonary artery infusion.

METHODS

Subjects were 30 male F344 rats. In experiment 1, we evaluated chemosensitivity of a rat colorectal adenocarcinoma cell line (RCN-9) using a colorimetric [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. In experiment 2, we injected RCN-9 cells into the left lung on day 0; on day 10, we measured tumor tissue blood flow before and after pulmonary arterial occlusion. In experiment 3, we injected RCN-9 cells into the left lung and conducted no further procedures in controls. The pulmonary artery infusion group underwent pulmonary artery infusion with 0.1 mg of cisplatin on day 3 and the sham group injection with saline solution alone. On day 10, rats were sacrificed and maximum tumor cross-section measured.

RESULTS

In experiment 1, the drug concentration required to inhibit cell growth 50% was 2.45 x 10(-6) M. In experiment 2, tumor tissue blood flow decreased significantly after arterial occlusion (p = 0.003). In experiment 3, the maximum tumor cross-section in the pulmonary artery infusion group was significantly smaller than in shams (p = 0.0027) and controls (p = 0.0019).

CONCLUSIONS

The pulmonary artery supplies tumors with blood, so this model appears useful in studying metastatic lung tumors, whose size was reduced significantly by pulmonary artery infusion with cisplatin. Pulmonary artery infusion is thus a promising modality in metastatic lung tumor treatment.

[A case of intrasellar meningioma mimicking pituitary adenoma]

The authors report a patient with a rare intrasellar meningioma mimicking pituitary adenoma. A 60-year-old man was admitted to our hospital for evaluation of general fatigue. He had no neurological deficit including visual function. Endocrinological tests revealed panhypopituitarism. The craniogram showed slight enlargement of the sella turcica with thinning of the dorsum sellae. CT scan and MR imaging demonstrated a homogeneously enhanced intrasellar mass with slight suprasellar extension. Partial removal of the mass was performed via the transsphenoidal approach because it was extremely firm and hemorrhagic. Histological diagnosis was transitional meningioma. The patient has been well for two years after surgery without tumor progression on MR imaging. It is mandatory to distinguish intrasellar meningioma from pituitary adenoma preoperatively because of marked difference in their treatment strategies. Despite recent advances in neurodiagnostic imaging, it may still be difficult to differentiate pituitary adenoma from intrasellar meningioma. When we re-evaluated the MR imaging, we recognized that the tumor had demonstrated specific findings, ruling out pituitary adenoma, namely bright and homogeneous enhancement, dense enhancement in the early phase on the dynamic MR study, and flow void signal within the mass. The authors emphasize that careful evaluations of MR imaging will allow the correct preoperative diagnosis in patients with intrasellar meningioma mimicking pituitary macroadenoma.

Dicationic dithiocarbamate carbapenems with anti-MRSA activity

A new class of 1 beta-methylcarbapenems bearing a doubly quaternarized 1,4-diazabicyclooctane (DABCO) substituted dithiocarbamate moiety at the C-2 side chain was prepared, and the biological profiles of the compounds, including in vitro and in vivo anti-MRSA activity and DHP-I susceptibility, were evaluated to identify a carbapenem derivative that was superior to BO-3482 (1). As a result, we discovered a 1 beta-methyl-2-[4-(4-carbamoylmethyl-1,4-diazabicyclo[2,2,2]octanediium-1-yl)methyl-1,2,3,6-tetrahydropyridinylthiocarbonylthio]carbapenem, 14a showing greater than 2-fold better anti-MRSA activity in a mouse infection model and 3-fold better DHP-I susceptibility as compared with BO-3482 (1).

[Effect of G-CSF (nartograstim) on neutropenia (leukopenia) induced by taxane in metastatic breast cancer--time-course changes in neutrophil and leukocyte counts]

Since 1997, we have used docetaxel and paclitaxel as the second-line and third-line chemotherapies against anthracycline-resistant metastatic breast cancer. However, these taxane compounds induced neutropenia and leukopenia, which may be reversed by G-CSF (Nartograstim). We thus examined the therapeutic efficacy of nartograstim for time-course changes in neutrophil and leukocyte counts in these patients. No difference was observed in neutrophil or leukocyte count whether the patient was treated with docetaxel or paclitaxel. Neutrophil and leukocyte counts reached a nadir on days 7 to 8 after administration. With a 5-6 day administration of nartograstim, neutrophil or leukocyte counts recovered by the second or third day after the nadir, indicating that the chemotherapy was given safely with nartograstim. In these same patients receiving a given treatment cycle, the number of days until reaching the nadir were almost identical for neutrophils and leukocytes; however, the duration of the nadir and the time to count recovery was significantly longer for neutrophils than for leukocytes. In the clinical setting, the parameter "leukocyte count" has been occasionally used for evaluation of the severity of myelosuppression, because the data is more readily available. However, at least during the nadir, the "neutrophil count" should be used as the parameter of choice.

NHE and ICAM-1 expression in hypoxic/reoxygenated coronary microvascular endothelial cells

Although Na+/H+ exchange (NHE) has been implicated in myocardial reperfusion injury, participation of coronary microvascular endothelial cells (CMECs) in this pathogenesis has been poorly understood. NHE-induced intracellular Ca2+ concentration ([Ca2+]i) overload in CMECs may increase the synthesis of intercellular adhesion molecules (ICAM), which is potentially involved in myocardial reperfusion injury. The present study tested the hypothesis that NHE plays a crucial role in [Ca2+]i overload and ICAM-1 synthesis in CMECs. Primary cultures of CMECs isolated from adult rat hearts were subjected to acidic hypoxia for 30 min followed by reoxygenation. Two structurally distinct NHE inhibitors, cariporide and 5-( N- N-dimethyl)-amiloride (DMA), had no significant effect on the acidic hypoxia-induced decrease in intracellular pH (pHi) of CMECs but significantly retarded pHi recovery after reoxygenation. These NHE inhibitors abolished the hypoxia- and reoxygenation-induced increase in [Ca2+]i. Expression of ICAM-1 mRNA was markedly increased in the vehicle-treated CMECs 3 h after reoxygenation, and this was significantly inhibited by treatment with cariporide, DMA, or Ca2+-free buffer. In addition, enhanced ICAM-I protein expression on the cell surface of CMECs 8 h after reoxygenation was attenuated by treatment with cariporide, DMA, or Ca2+-free buffer. These results suggest that NHE plays a crucial role in the rise of [Ca2+]i and ICAM-1 expression during acidic hypoxia/reoxygenation in CMECs. We propose that inhibition of ICAM-1 expression in CMECs may represent a novel mechanism of action of NHE inhibitors against ischemia-reperfusion injury.

A proposal for the histopathological diagnosis of ductal carcinoma in situ of the breast

BACKGROUND

As the incidence of ductal carcinoma in situ (DCIS) is increasing, it is necessary to make a guideline for the pathological examination and diagnosis of DCIS, by creating criteria based on clinical and biological aspects of the disease.

METHOD

We collected biopsy specimens originally diagnosed as benign lesions, from patients who subsequently developed invasive carcinoma in the ipsilateral breast. The histology of the biopsy specimens was re-evaluated principally according to the 1995 Philadelphia Consensus on DCIS. Histopathological agreement on each biopsy specimen was made by the JBCS Study Group members under a multiviewer microscope. In the course of making conclusive agreements among the pathologists, we developed a consensus for the histopathological diagnosis of DCIS, especially non-comedo types.

RESULTS

DCIS is defined as a carcinoma of ductal epithelial origin, without any evidence of stromal invasion. It is necessary to note the methods of pathologic examination required to diagnose DCIS. Stromal invasion is an important prognostic factor, and should be diagnosed with caution. Classification of proliferative ductal lesions as benign or malignant (DCIS), the subtype of DCIS (nuclear grade, architecture, and necrosis), and the histological grading of DCIS are proposed and recommended.

CONCLUSION

Although we have made a new proposal according to current concepts, there are still several unresolved problems. Thus further examination and modification will be necessary in the future.

Anatomical keys and pitfalls in living donor liver transplantation

The surgery of living donor liver transplantation is more technically challenging than cadaveric whole liver transplantation and liver resection for the treatment of various pathological conditions. It requires a thorough understanding of the intra- and extra-hepatic anatomical relationships between the portal vein, hepatic artery, biliary tract, and hepatic vein, and also their respective contributions to liver physiology. Although a precise understanding of general anatomical principles is the key to correctly performing living donor liver transplantation procedures, anatomic anomalies are often present, and the means of detecting them and the surgical methods of coping with them represent technical challenges. In this monograph, we describe the anatomical keys and pitfalls of living donor liver transplantation surgery based on our own experience with more than 1800 hepatectomies, and 150 living donor liver transplantations. We also elaborate on techniques of selective intermittent vascular occlusion and their teleological and practical background.

c-MET expression in myofibroblasts: role in autocrine activation and prognostic significance in lung adenocarcinoma

Hepatocyte growth factor (HGF) plays important roles in tumor development and progression. It is currently thought that the main action of HGF is of a paracrine nature: HGF produced by mesenchymal cells acts on epithelial cells that express its receptor c-MET. In this investigation, we explored the significance of c-MET expression in myofibroblasts, both in culture and in patients with lung adenocarcinoma. We first showed that human myofibroblasts derived from primary lung cancer expressed c-MET mRNA and protein by reverse transcription-polymerase chain reaction and Western blot analysis. Proliferation of myofibroblasts was stimulated in a dose-dependent manner by exogenously added recombinant human HGF whereas it was inhibited in a dose-dependent manner by neutralizing antibody to HGF. The addition of HGF in the culture medium stimulated tyrosine phosphorylation of c-MET. The c-MET protein was immunohistochemically detected in myofibroblasts in the invasive area of lung adenocarcinoma. Finally, the prognostic significance of c-MET expression in stromal myofibroblasts was explored in patients with small-sized lung adenocarcinomas. c-MET-positive myofibroblasts were observed in 69 of 131 cases (53%). A significant relationship between myofibroblast c-MET expression and shortened patient survival was observed in a whole cohort of patients including all pathological stages (two-sided P: = 0.0089 by log-rank test) and in patients with stage IA disease (two-sided P: = 0.0019 by log-rank test). These data suggest that the HGF/c-MET system constitutes an autocrine activation loop in cancer-stromal myofibroblasts. This autocrine system may play a role in invasion and metastasis of lung adenocarcinoma.

Practical synthesis of a 1beta-methylcarbapenem, J-111,225, using 4-mercapto-2-[4-(N-methylaminomethyl)phenyl]pyrrolidine as a precursor

An effective and practical procedure for the synthesis of J-111,225 (1), a new 1beta-methylcarbapenem, was developed using 4-mercapto-2-14-(N-methylaminomethyl)phenyl]pyrrolidine (2a) as a precursor. The coupling reaction of 2a with p-nitrobenzyl (PNB)-protected 1beta-methylcarbapenem enolphosphate 3a and successive removal of PNB group afforded J-111,225 (1) in significantly increased yield compared to the ordinary procedure using a C-2 side-chain thiol with amino-protective groups.

[A case of cervical subpial lipoma]

The authors report the rare case of a 48-year-old woman with a cervical subpial lipoma unassociated with spinal dysraphism. Her symptoms were progressive weakness and numbness in the four extremities and the neurological symptom of mild cervical myelopathy. Plain radiographs of the cervical spine showed diffuse widening of the spinal canal, which was occupied by a large low-density mass revealed by axial CT scan. MR imaging identified the mass as being dorsolateral to the cord in the intradural region. It was hyperintense on both T1- and T2-weighted images. Axial images with fat suppression sequence clearly showed dorsal nerve roots traveling through the lesions, but the interface between the spinal cord and lesion was not well demarcated. A cervical laminectomy between C3-6 revealed a yellowish subpial mass after the dura was opened. The mass was only partially resected and intraoperative SEP monitoring data remained normal including N20 latency. Histological examination found mature adipose tissue covered by thickened pia mater, which was compatible with a diagnosis of lipoma. After surgery, no complications occurred and the patient's myelopathy subsequently improved. Subpial spinal lipomas unassociated with dysraphism are uncommon and they are reported in only 1% of all spinal cord tumors. They are thought to arise from premature dysjunction of the cutaneous ectoderm during neural tube formation. Without any invasive procedure, MR imaging is indispensable to show their longitudinal dimension as well as their infiltrative extension into the spinal cord. The main purpose of surgery is to decompress the lipoma from the adjacent neural structures, because it is benign in nature and there is no cleavage plane identifiable between the lipoma and the spinal cord.

Hepatic phenylalanine metabolism measured by the [13C]phenylalanine breath test

BACKGROUND

The amino acid clearance test including phenylalanine is known to reflect liver functional reserve, which correlates with surgical outcome; however, the procedure is not clinically useful because of its laborious and time-consuming nature. This study evaluates whether phenylalanine oxidation capacity measured by a breath test could reflect liver functional reserve.

DESIGN

We determined phenylalanine oxidation capacity in 42 subjects using the L-[1-13C]phenylalanine breath test (PBT). The 13CO2 breath enrichment was measured at 10-min intervals for 120 min after oral administration of 100 mg of L-[1-13C]phenylalanine. Subjects were divided into the following three groups according to their plasma retention rate of indocyanine green at 15 min (ICG R15): Group I (ICG R15 < 10%), Group II (ICG R15 10--20%), and Group III (ICG R15 > 20%). First, we determined the parameters of the phenylalanine oxidation capacity that differentiated these groups and then, using these parameters, we compared the PBT with the ICG clearance test, Child-Pugh classification score and standard liver blood tests.

RESULTS

The %13C dose h(-1) at 30 min and cumulative excretion at 80 min were significantly different among the three groups (P < 0.05). These two parameters significantly correlated with the ICG R15, Child-Pugh classification score (P < 0.0001) and results of standard liver blood tests (P < 0.05).

CONCLUSIONS

Phenylalanine oxidation capacity measured by the PBT was reduced according to the severity of liver injury assessed by the ICG clearance test, Child-Pugh classification, and standard liver blood tests. These results indicate that the PBT can be used as a noninvasive method to determine liver functional reserve.

Small-for-size grafts in living-related liver transplantation

BACKGROUND

The problems associated with small-for-size grafts in living-related liver transplantation are not fully understood.

STUDY DESIGN

A consecutive series of 79 patients underwent 80 living-related liver transplantation procedures, including one retransplant, at the University of Tokyo from January 1996 to January 2000. They were divided into two groups by graft size: graft weight/recipient standard liver volume ratios of 40% or less (n = 24), and more than 40% (n = 56). Preoperative status, mortality, morbidity, duration of hospital stay, and postoperative graft function were examined and compared between the groups.

RESULTS

The rate of patients who were restricted to the intensive care unit preoperatively was comparable between the groups (33% versus 21%, p = 0.27). The mean standard liver volume ratios were 37% in the small graft group and 84% in the large group. Survival rates were 80% (5 of 24) for the small graft group, which was significantly lower than that for the large group (96%, 54 of 56, p = 0.02). The rate of acute rejection was comparable between the groups (33% versus 43%, p = 0.47). Vascular complication was observed in 17% of the small graft group patients and 23% of the large group (p = 0.77). No difference was observed in the frequency of bile leakage or bile duct stenosis (25% versus 21%, p=0.77). Hyper-bilirubinemia and elongation of prothrombin time persisted longer in the small graft group than in the large group (p < 0.0001 for both).

CONCLUSIONS

Our surgical results may suggest that a graft weight ratio of 40% or less provides a lower chance of survival after living-related liver transplantation.