Efficacy of a motilin receptor agonist (ABT-229) for the treatment of gastro-oesophageal reflux disease

BACKGROUND

ABT-229 is a potent motilin agonist without significant antibiotic activity. It has been shown to improve gastric emptying in humans and to increase lower oesophageal sphincter pressure in cats.

AIM

To assess the efficacy of four different doses of ABT-229 (1.25 mg, 2.5 mg, 5 mg, 10 mg b.d.) compared to placebo in the treatment of gastro-oesophageal reflux disease, and to determine its safety in patients with gastro-oesophageal reflux disease.

METHODS

In a double-blind, multicentre study, 324 patients with heartburn were randomized to receive four different doses of ABT-229 or placebo for 8 weeks. The efficacy was evaluated by Patient Symptom Questionnaire, daily diary, endoscopy and global evaluation of efficacy.

RESULTS

There were no statistically significant improvement scores for any of the ABT-229 treatment groups vs. the placebo group in any of the efficacy parameters. Reflux symptom scores were significantly worse after treatment in the dyspeptic group. ABT-229 appeared to be well tolerated and safe in total daily doses up to 20 mg.

CONCLUSION

ABT-229 appears to have limited, if any, clinical utility in the treatment of gastro-oesophageal reflux disease.

High-performance liquid chromatographic methods for the determination of topoisomerase II inhibitors

Various methods for separating eleven different types of topoisomerase II (TOPO-2) inhibitors, including epipodophyllotoxins, anthracyclines, anthracenediones, anthrapyrazoles, anthracenebishydrazones, indole derivatives, aminoacridines, benzisoquinolinediones, isoflavones, bisdioxopiperazines and thiobarbituric acids, are summarized. Proper sample preparation and storage is critical to the successful analysis of some TOPO-2 inhibitors due to difficulties associated with adsorption, instability and complex biological components. Solid-phase and liquid-liquid extractions are widely used to separate TOPO-2 inhibitors from biological samples, although simple deproteinization followed by direct analysis of the supernatant is preferable to extraction based on its speed and simplicity. High-performance liquid chromatography (HPLC) is the favored method for the bioanalysis of TOPO-2 inhibitors. UV or diode array detection is generally employed for early pharmacokinetic studies, while fluorescence or electrochemical detection is used more frequently for analytes with fluorescent or oxidative-reductive properties. For analyses requiring highly sensitive and/or specific detection, electrospray mass spectrometry (ESI-MS or ESI-MS-MS) provides a suitable alternative. A comprehensive compilation of the HPLC techniques currently used to separate TOPO-2 inhibitors will aid the future development of analytical methods for new TOPO-2 inhibitors.

Single imaging modality evaluation of living donors in liver transplantation: magnetic resonance imaging

BACKGROUND

Liver graft size, anatomy of the bile duct and the vascular inflow and outflow are essential for living related liver transplantation (LRLT). Preoperative delineation of those variations that would change the operative procedure to achieve a successful result especially in an emergency condition.

PURPOSE

Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a safe operation when selecting potential liver transplant living donors. We used a different magnetic resonance (MR) imaging technique, which enabled to us to exploit the anatomical landmark of the liver, signal enhancement of blood flow in the abdomen, and the intrahepatic biliary routes inside the liver. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three-dimensional fashion and the whole examination finished within 30 min.

METHODS

Modification of the standard MR technique was performed on a superconductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the anatomy of the hepatic arteries, hepatic veins, portal venous system, bile ducts, and liver size in potential liver transplant living donors. These anatomical structures were compared with traditional imaging methods.

RESULTS

In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The images were well displayed in a three-dimensional fashion, which had good correlation with images from traditional imaging modalities and operative findings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was well correlated with the liver graft within 3.9-12.5% variation. In the major hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded from graft donation due to the complicated arterial supply to the left liver. According to the anatomical variation, surgical procedures in graft harvesting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation.

CONCLUSION

MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evaluation. It may replace the traditional conventional catheter angiography, computed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.

Prospective study of Helicobacter pylori eradication therapy in stage I(E) high-grade mucosa-associated lymphoid tissue lymphoma of the stomach

PURPOSE

High-grade mucosa-associated lymphoid tissue (MALT) lymphomas of the stomach are generally believed to be Helicobacter pylori-independent, autonomously growing tumors. However, anecdotal cases of regression of high-grade lymphomas after the cure of H pylori infection had been described. The present prospective study was conducted to evaluate the effect of anti-H pylori therapy in stage I(E) high-grade gastric MALT lymphomas.

PATIENTS AND METHODS

Sixteen patients with H pylori infection and stage I(E) gastric high-grade MALT lymphoma consented to a brief antibiotic therapy as first-line treatment from June 1995 through April 2000. Then, patients underwent intensive endoscopic follow-up examinations (+/- endoscopic ultrasonography) with biopsy to evaluate tumor response. Patients with significant improvement of gross lesions that accompanied regression of large cells were followed up without additional treatment. Patients without significant improvement were immediately referred to systemic chemotherapy.

RESULTS

Eradication of H pylori was achieved in 15 patients and was accompanied by rapid gross tumor regression and disappearance of large cells in 10. All 10 of these patients with early response had subsequent complete histologic remission of lymphoma. The complete remission rate was 62.5% (95% confidence interval, 35.8% to 89.1%). The response rate was not affected by the tumor grading (proportion of large blast cells within the tumor) but was adversely affected by the depth of tumor invasion. At a median follow-up of 43.5 months (range, 21.1 to 67.4 months), all 10 of these patients remained lymphoma-free. The median duration of complete response was 31.2 months (range, 14.4 to 49.1 months).

CONCLUSION

These results suggest that high-grade transformation is not necessarily associated with the loss of H pylori dependence in early-stage MALT lymphomas of the stomach.

Expression of multidrug resistance 1 and glutathione-S-transferase-Pi protein in nasopharyngeal carcinoma

Radiotherapy is the modality of choice for the treatment of nasopharyngeal carcinoma (NPC). However, systemic chemotherapy has recently been found to play an increasing role in the treatment of advanced or metastatic disease. The status of drug resistance gene expression that has crucial impact on chemotherapy has not been fully addressed for patients with NPC. In this study, we examined the expression of multidrug resistance 1 (MDR-1) and glutathione-S-transferase-Pi (GST-Pi) in primary, recurrent, and metastatic NPC using results of immunohistochemical examinations. The results were correlated with the expression of Epstein-Barr virus (EBV) latent protein, latent membrane protein 1 (LMP1), and clinicopathologic features, including stage, histopathologic types, and survival rates. MDR-1 protein expression was detected in 18 (12.6%) of 143 patients with primary NPC, 14 (32.6%) of 43 with recurrent NPC, and O (0%) of 20 with metastatic NPC, whereas 83 (58%) of 143 patients with primary NPC, 30 (69.8%) of 43 with recurrent NPC, and 13 (65%) of 20 with metastatic NPC expressed GST-Pi. EBV-LMP1 was expressed in 59 (41.3%) of 143 patients with primary NPC, 23 (53.5%) of 43 with recurrent NPC, and 9 (45%) of 20 with metastatic NPC. Simultaneous expression of MDR1 and GST-Pi was observed in 13 (72.2%) of 18 patients with primary NPC and 12 (85.7%) of 14 with recurrent NPC. The expression of LMP1 was detected in only 6 of the 13 patients with primary NPC and 6 of the 12 with recurrent NPC. We concluded that the expression of GST-Pi was more frequent in NPC tumor tissues than the expression of MDR-1. The expression of MDR-1 correlated with clinicopathologic features of primary NPC, including the histopathologic types and survival rates, but not with disease stage. The expression of GST-Pi did not correlate with clinicopathologic features. The expression of MDR-1 and GST-Pi did not correlate with expression of EBV-LMP1 for patients with NPC.

Clinical features of familial gout and effects of probable genetic association between gout and its related disorders

We examined whether the age at onset, gender, arthritic manifestations, and tophus formation in familial gout are different from those in nonfamilial gout, and we also examined the contributory effect of genetic association to the concurrence of hypertriglyceridemia, hypercholesterolemia, type 2 diabetes mellitus (DM), hypertension, obesity, and renal insufficiency with gout in Taiwan. A total of 21,373 gout patients' data from Ho-Ping Gout database were analyzed in this study retrospectively. The clinical and laboratory data were compared between familial and nonfamilial gout. Mean age at onset of gout in familial subjects was significantly 7.5 years lower than that of nonfamilial subjects (40.9 +/- 13.4 v 48.4 +/- 14.2 years, P =.0001), while gender, arthritic severity, and tophus formation were not significantly different between these 2 groups. Familial gout had lower serum triglyceride (TG), total cholesterol (TC), and percentage of hypertension than nonfamilial gout (182.4 +/- 125.3 v 195.9 +/- 135.8 mg/dL, P =.0001; 207.5 +/- 42.5 v 210.4 +/- 48.8 mg/dL, P =.0003; and 19.57% v 22.56%, P <.0001, respectively). Their serum creatinine, body mass index (BMI), and percentage of type 2 DM were not significantly different. Our results demonstrate that familial gout is associated with precocious onset. Furthermore, the contributory effect of genetic association to the concurrence of hyperlipidemia and hypertension with gout is less than that of environmental factors, while the effect of genetic association to the concurrence of obesity, type 2 DM, and renal insufficiency with gout is equivalent to that of environmental factors.

Formation of brainstem (nor)adrenergic centers and first-order relay visceral sensory neurons is dependent on homeodomain protein Rnx/Tlx3

Brainstem visceral sensory and (nor)adrenergic neurons play crucial roles in modulating cardiovascular and respiratory functions. The origins and formation of these neurons are poorly understood. Here we show that these two classes of neurons are derived from Mash1-positive precursor cells, and can be prospectively identified by combinatorial expression of two homeobox genes, Rnx and Phox2 (Phox2a or Phox2b). It was previously shown that Rnx-deficient mice die from respiratory failure. Here we show that Rnx function is required for formation of first-order relay visceral sensory neurons in the brainstem. In addition, as in Phox2b-deficient mice, the development of most (nor)adrenergic centers is compromised in Rnx mutants. We also provide genetic evidence to show that Rnx and Phox2 proteins may function independently to specify the (nor)adrenergic phenotype. Our studies reveal a surprising ontogenetic relationship between relay visceral sensory and (nor)adrenergic neurons, and suggest that it may be a common theme in the developing nervous system that the same set of transcriptional regulators is associated with formation of multiple components within a neuronal network.

Electron microscopic observations of a marine fish iridovirus isolated from brown-spotted grouper, Epinephelus tauvina

The morphogenesis and the ultrastructure of a marine fish iridovirus isolated from diseased grouper, Epinephelus tauvina were studied by electron microscopy. The virus was grown on a marine fish cell line (GP) at 25 degrees C. After appearance of advanced cytopathic effect (CPE), various morphogenetic stages of virus amplification, maturation and assembly were detected in the cytoplasm of virus-infected cells. The matured nucleocapsids were probably formed by insertion of electron-dense core material into a partly forming empty capsid just before completely sealed. The nucleocapsids were located at the assembly sites as pseudocrystalline arrays or scattered individually. In the late phase of infection, the nucleocapsids were enveloped and released by budding from the plasma membrane. The budding virus particles could directly enter neighbouring cells by endocytosis to start the next round infection. Ultrastructure of the grouper iridovirus was studied using the methods of enzymatic digestions and detergent degradations. The purified iridovirus particles showed a three-layered membrane including an external lipoprotein envelope, an inner periodic protein capsid and a lipid-containing membrane. The regular array of surface capsid subunits was observed after degradation with detergent.

Acute oxalate nephropathy induced by star fruit in rats

In this study, we intend to establish a connection between star fruit and acute oxalate nephropathy and also investigate predisposing factors for its development. Male Sprague-Dawley rats of 180 to 200 g were assigned to four groups; namely, control, experimental, fasting, and water-deprivation groups. The former two groups were subjected to both fasting and water deprivation, whereas the latter two groups were subjected to either fasting or water deprivation, respectively. Except for tap water for controls, the remaining groups were administered 4 mL/100 g of body weight of sour star fruit juice with an oxalate concentration of 2.46 g/dL. After these procedures, serial measurement of serum creatinine levels and kidney pathological examination were performed. Peak serum creatinine levels in the control, experimental, fasting, and water-deprivation groups were 0.50 +/- 0.04, 1.46 +/- 0.26, 0.68 +/- 0.20, and 0.52 +/- 0.08 mg/dL, respectively. The experimental group had a greater peak serum creatinine level (P < 0.05). Mean serum creatinine levels of the experimental group days 0, 1, 2, 3, 4, and 5 were 0.43 +/- 0.03, 1.11 +/- 0.18, 1.31 +/- 0.27, 1.16 +/- 0.28, 0.8 +/- 0.26, and 0.82 +/- 0.28 mg/dL, respectively. Mean serum creatinine levels days 1 to 3 were greater than that day 0 (P < 0.05). Pearson's correlation analysis of peak serum creatinine level and kidney weight for the experimental group showed a significant correlation (R = 0.75; P < 0.05; n = 9). In addition to typical changes of oxalate nephropathy, kidney pathological examination showed many refractile oxalate crystals with all rainbow colors under polarized light microscopy in the experimental group. In conclusion, sour star fruit with abundant oxalate contents could cause acute oxalate nephropathy in rats under the conditions of fasting and water deprivation.

Nuclear factor-kappaB (NF-kappaB) regulates proliferation and branching in mouse mammary epithelium

The nuclear factor-kappaB (NF-kappaB) family of transcription factors has been shown to regulate proliferation in several cell types. Although recent studies have demonstrated aberrant expression or activity of NF-kappaB in human breast cancer cell lines and tumors, little is known regarding the precise role of NF-kappaB in normal proliferation and development of the mammary epithelium. We investigated the function of NF-kappaB during murine early postnatal mammary gland development by observing the consequences of increased NF-kappaB activity in mouse mammary epithelium lacking the gene encoding IkappaBalpha, a major inhibitor of NF-kappaB. Mammary tissue containing epithelium from inhibitor kappaBalpha (IkappaBalpha)-deficient female donors was transplanted into the gland-free mammary stroma of wild-type mice, resulting in an increase in lateral ductal branching and pervasive intraductal hyperplasia. A two- to threefold increase in epithelial cell number was observed in IkappaBalpha-deficient epithelium compared with controls. Epithelial cell proliferation was strikingly increased in IkappaBalpha-deficient epithelium, and no alteration in apoptosis was detected. The extracellular matrix adjacent to IkappaBalpha-deficient epithelium was reduced. Consistent with in vivo data, a fourfold increase in epithelial branching was also observed in purified IkappaBalpha-deficient primary epithelial cells in three-dimensional culture. These data demonstrate that NF-kappaB positively regulates mammary epithelial proliferation, branching, and functions in maintenance of normal epithelial architecture during early postnatal development.

Weight reduction increases plasma levels of an adipose-derived anti-inflammatory protein, adiponectin

Adiponectin, an adipose tissue-specific plasma protein, was recently revealed to have anti-inflammatory effects on the cellular components of vascular wall. Its plasma levels were significantly lower in men than in women and lower in human subjects with obesity, type 2 diabetes mellitus, or coronary artery disease. Therefore, it may provide a biological link between obesity and obesity-related disorders such as atherosclerosis, against which it may confer protection. In this study, we observed the changes of plasma adiponectin levels with body weight reduction among 22 obese patients who received gastric partition surgery. A 46% increase of mean plasma adiponectin level was accompanied by a 21% reduction in mean body mass index. The change in plasma adiponectin levels was significantly correlated with the changes in body mass index (r = -0.5, P = 0.01), waist (r = -0.4, P = 0.04) and hip (r = -0.6, P = 0.0007) circumferences, and steady state plasma glucose levels (r = -0.5, P = 0.04). In multivariate linear regression models, the increase in adiponectin as a dependent variable was significantly related to the decrease in hip circumference (beta = -0.16, P = 0.028), after adjusting body mass index and waist circumference. The change in steady state plasma glucose levels as a dependent variable was related to the increase of adiponectin with a marginal significance (beta = -0.92, P = 0.053), after adjusting body mass index and waist and hip circumferences. In conclusion, body weight reduction increased the plasma levels of a protective adipocytokine, adiponectin. In addition, the increase in plasma adiponectin despite the reduction of the only tissue of its own synthesis suggests that the expression of adiponectin is under feedback inhibition in obesity.

The role of age and salivation in acid clearance in symptomatic patients with gastro-oesophageal reflux disease

BACKGROUND

Cisapride has been shown to have not only prokinetic effects, but also salivary stimulating effects. Both of these mechanisms play an important role in the acid clearance of the oesophagus.

AIM

To access the efficacy of cisapride in facilitating acid clearance in patients with symptomatic gastro-oesophageal reflux disease.

METHODS

Fifteen older adults and 15 younger adults with symptomatic gastro-oesophageal reflux disease completed the study. The acid clearance test was accomplished by infusing 15 mL of 0.1 N HCl into the distal oesophagus, and the number of swallows was determined to achieve an oesophageal pH of 4.0. This was accomplished under baseline conditions and salivary stimulation with a peppermint lozenge. After 1 week of treatment with cisapride (10 mg, q.d.s.), the acid clearance test was repeated.

RESULTS

The lozenge produced a significant decrease in the number of swallows compared to baseline in both groups (P < 0.01). There was a significant decrease in the number of swallows after the treatment with cisapride compared to baseline in both groups (P < 0.01). No significant difference was found in the number of swallows when comparing cisapride with lozenge.

CONCLUSIONS

Cholinergic stimulation of salivation is an effective means of facilitating oesophageal acid clearance. Drugs, such as 5 hydroxytriptamine (5-HT)4-receptor agonists, should be considered as potentially important compounds in the treatment of gastro-oesophageal reflux disease.

NF-kappaB mediates FGF signal regulation of msx-1 expression

The nuclear factor-kappaB (NF-kappaB) family of transcription factors is involved in proliferation, differentiation, and apoptosis in a stage- and cell-dependent manner. Recent evidence has shown that NF-kappaB activity is necessary for both chicken and mouse limb development. We report here that the NF-kappaB family member c-rel and the homeodomain gene msx-1 have partially overlapping expression patterns in the developing chick limb. In addition, inhibition of NF-kappaB activity resulted in a decrease in msx-1 mRNA expression. Sequence analysis of the msx-1 promoter revealed three potential kappaB-binding sites similar to the interferon-gamma (IFN-gamma) kappaB-binding site. These sites bound to c-Rel, as shown by electrophoretic mobility shift assay (EMSA). Furthermore, inhibition of NF-kappaB activity significantly reduced transactivation of the msx-1 promoter in response to FGF-2/-4, known stimulators of msx-1 expression. These results suggest that NF-kappaB mediates the FGF-2/-4 signal regulation of msx-1 gene expression.

In vivo toxicity, pharmacokinetic features and tissue distribution of N-[2-(2,5-dimethoxyphenylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea (HI-236), a potent non-nucleoside inhibitor of HIV-1 reverse transcriptase

N-[2-(2,5-Dimethoxyphenylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea (HI-236, CAS 233271-65-3) possesses potent anti-viral activity against zidovudine-sensitive as well as multidrug-resistant HIV-1 (human immunodeficiency virus) strains. The purpose of the present study was to examine in vivo toxicity, pharmacokinetic features and tissue distribution of HI-236 in mice. HI-236 had an elimination half-life of 85.8 min after i.v. administration and 86.6 min after i.p. administration. The systemic clearance of HI-236 was 4337 ml/h/kg after i.v. administration and 10,130 ml/h/kg after i.p. administration. Following i.v. injection, HI-236 rapidly distributed to and accumulated in multiple tissues with particularly high accumulation in lung, adipose tissue, skin, urinary bladder, adrenal gland and uterus + ovary. The concentration of HI-236 in brain tissue was comparable to that in the plasma, indicating that HI-236 easily crosses the blood-brain barrier. Following i.p. injection, HI-236 was rapidly absorbed with a tmax values of 5.6 min and showed linear pharmacokinetics within the dose range of 10-80 mg/kg. Following oral administration, HI-236 was absorbed with a tmax of 5.8 min. The intraperitoneal bioavailability was estimated at 42.9%, while the oral bioavailability was only 2.2%. The pharmacokinetic study described herein provides the basis for advanced pharmacodynamic study of HI-236.

Risk for occupational injury of handicapped workers in Taiwan

The current study investigated occupational risk of handicapped workers relative to nonhandicapped workers and used the standardized mortality ratio as an index that handicapped workers were at elevated risk for occupational injury. A total of 6,327 records of disabling occupational injuries beyond first aid treatment from January to December, 1999 were collected and analyzed. The ratio of the standardized mortality ratio of the handicapped vs nonhandicapped workers indicated that occupational injury risk of handicapped workers must be seriously examined for the reasons for this unexpectedly high occupational risk.

Weight reduction increases plasma levels of an adipose-derived anti-inflammatory protein, adiponectin

Adiponectin, an adipose tissue-specific plasma protein, was recently revealed to have anti-inflammatory effects on the cellular components of vascular wall. Its plasma levels were significantly lower in men than in women and lower in human subjects with obesity, type 2 diabetes mellitus, or coronary artery disease. Therefore, it may provide a biological link between obesity and obesity-related disorders such as atherosclerosis, against which it may confer protection. In this study, we observed the changes of plasma adiponectin levels with body weight reduction among 22 obese patients who received gastric partition surgery. A 46% increase of mean plasma adiponectin level was accompanied by a 21% reduction in mean body mass index. The change in plasma adiponectin levels was significantly correlated with the changes in body mass index (r = -0.5, P = 0.01), waist (r = -0.4, P = 0.04) and hip (r = -0.6, P = 0.0007) circumferences, and steady state plasma glucose levels (r = -0.5, P = 0.04). In multivariate linear regression models, the increase in adiponectin as a dependent variable was significantly related to the decrease in hip circumference (beta = -0.16, P = 0.028), after adjusting body mass index and waist circumference. The change in steady state plasma glucose levels as a dependent variable was related to the increase of adiponectin with a marginal significance (beta = -0.92, P = 0.053), after adjusting body mass index and waist and hip circumferences. In conclusion, body weight reduction increased the plasma levels of a protective adipocytokine, adiponectin. In addition, the increase in plasma adiponectin despite the reduction of the only tissue of its own synthesis suggests that the expression of adiponectin is under feedback inhibition in obesity.

Genomic structure and transcriptional regulation of the early B cell gene chB1

The avian B cell differentiation Ag chB1 is a membrane glycoprotein relative of the mammalian B cell differentiation Ag CD72. Unlike CD72, this C-type lectin is expressed in relatively high levels on immature B cells in the bursa of Fabricius and is down-regulated on mature B cells in the periphery. An immunoreceptor tyrosine-based inhibitory motif in the chB1 cytoplasmic tail suggests a potential regulatory role in intrabursal B cell development. To gain further insight into the selective expression and function of chB1, we determined the genomic organization of chB1 and examined the mechanism of its transcriptional regulation. The 8-exon chB1 gene proved to have very similar organization to that of mouse CD72, further supporting the idea that chB1 is a CD72 relative. As for mouse CD72, the chB1 promoter region lacks a TATA box but contains a conserved initiator element. The 131-bp region (-161 to -30) proximal to the transcriptional start site, which contains a potential early B cell factor binding site, is essential for the B lineage stage-specific transcription of chB1, whereas PU.1 and B cell-specific activator protein/Pax5 have been shown to play important roles in CD72 promoter activity and cell-type specificity. This analysis suggests that differences in transcriptional regulation of these phylogenetically related genes may determine the differences in expression pattern and, therefore, the function of avian chB1 and mammalian CD72 during B cell development.

Interventional radiologic procedures in liver transplantation

Postoperative biliary and vascular complications contribute significantly to morbidity and mortality in liver transplantation. Interventional radiologists are an integral part of the multidisciplinary team necessary for optimizing the management of these complications. During a 15-year period, 39 cadaveric and 25 living related liver transplantations were performed at the Chang Gung Memorial hospital, Taiwan. Of 64 liver transplant recipients, 9 (3 adult and 6 pediatric) underwent 13 interventional radiological procedures for the treatment of biliary sludge-casts (n = 2), bile duct occlusion or stenosis (n = 2), hepatic veins thrombosis (n = 1), hepatic veins stenosis (n = 1), portal vein stenosis with splenorenal shunting (n = 1), biloma (n = 1), and infected fluid collection or ascites (n = 4). Antegrade or retrograde interventional approach was used to successfully treat all biliary complications, and all percutaneous drainage procedures were effective in the control of intra-abdominal fluid collections. Portal vein stenosis was treated by balloon dilatation, and the associated splenorenal shunt was closed by metallic coil embolization via transhepatic catheterization of the portal vein. Hepatic vein stenosis was effectively treated by balloon dilatation and expandable metallic stent deployment via transfemoral and jugular venous approaches, respectively. Hepatic vein thrombosis was only partially lysed by transvenous streptokinase administration, and surgical thrombectomy was needed to achieve complete recanalization. The total success rate of the interventional procedures was 92 % with no procedure-related complications. The overall survival rate in this series is 89 %, and all patients who underwent living related liver transplantation maintain to date a 100 % survival rate. We can conclude that interventional radiological procedures are very useful for managing biliary and vascular complications after liver transplantation. These techniques provide a cure in most situations, thus obviating the need for further surgical intervention or re-transplantation.

In vivo pharmacokinetics and metabolism of anti-human immunodeficiency virus agent D4T-5'-[p-bromophenyl methoxyalaninyl phosphate] (SAMPIDINE) in mice

d4T-5'-[p-Sampidine, bromophenyl methoxyalaninyl phosphate] (HI-113), a novel aryl phosphate derivative of stavudine (d4T), exhibits substantially more potent anti-human immunodeficiency virus activity than d4T. The purpose of the present study was to investigate the in vivo pharmacokinetics and metabolism of this promising new anti-HIV agent in mice. Here, we report that HI-113 forms two active metabolites with favorable pharmacokinetics after systemic administration. Plasma HI-113 concentrations were measured by analytical high-performance liquid chromatography and the pharmacokinetic parameters were estimated using the WinNonlin program. After intravenous administration, the elimination half-life (t(1/2)) of HI-113 was 3.6 min with a systemic clearance of 174.5 ml/min/kg. HI-113 was converted to the active metabolites alaninyl-d4T-monophosphate (ala-d4T-MP) and d4T. The T(max) values for ala-d4T-MP and d4T derived from intravenously administered HI-113 were 5.1 and 17.4 min, respectively. The elimination half-life for synthetic ala-d4T-MP was 38.9 min after intravenous administration. Ala-d4T-MP was metabolized to form d4T (T(max) = 5.0 min). The elimination half-life of d4T derived from intravenously administered ala-d4T-MP (32.4 min) was similar to the elimination half-life of intravenously administered d4T (26.6 min). In contrast, the elimination half-life of d4T derived from HI-113 was substantially longer (116.2 min). Similarly, the elimination half-life of ala-d4T-MP derived from HI-113 (138.8 min) was markedly longer than the elimination half-life of ala-d4T-MP given intravenously (38.9 min). Following oral administration of HI-113, the elimination half-lives of ala-d4T-MP (56.1 min) and d4T (102.6 min) were also prolonged.

In vivo antitumor activity of bis(4,7-dimethyl-1,10-phenanthroline) sulfatooxovanadium(IV) (METVAN [VO(SO4)(Me2-Phen)2])

The compound bis(4,7-dimethyl-1,10-phenanthroline) sulfatooxovanadium(IV) (METVAN [VO(SO4)(Me2-Phen)2]), exhibits potent cytotoxicity against human cancer cells at low micromolar concentrations. At concentrations > or = 1 microM, METVAN treatment was associated with a nearly complete loss of the adhesive, migratory, and invasive properties of the treated tumor cell populations. METVAN did not cause acute or subacute toxicity in mice at dose levels ranging from 12.5 mg/kg to 100 mg/kg. Therapeutic plasma concentrations > or = 5 microM were rapidly achieved and maintained in mice for at least 24 h after i.p. bolus injection of a single 10 mg/kg nontoxic dose of METVAN. At this dose level, the maximum plasma METVAN concentration was 37.0 microM, which was achieved with a t(max) of 21.4 min. Plasma samples (diluted 1:16) from METVAN-treated mice killed 85% of human breast cancer cells in vitro. METVAN was slowly eliminated with an apparent plasma t(1/2) of 17.5 h and systemic clearance of 42.1 ml/h/kg. In accordance with its potent in vitro activity and favorable in vivo pharmacokinetics, METVAN exhibited significant antitumor activity and delayed tumor progression in CB.17 severe combined immunodeficient (SCID) mouse xenograft models of human glioblastoma and breast cancer. In these experiments, METVAN was administered in daily injections of a single nontoxic 10 mg/kg i.p. dose on 5 consecutive days per week for 4 consecutive weeks beginning the day after the s.c. inoculation of U87 glioblastoma or MDA-MB-231 breast cancer cells. At 40 days after the inoculation of tumor cells, the U87 tumor xenografts in the vehicle-treated control SCID mice were much larger than those of the mice treated with METVAN (4560 +/- 654 mm(3) versus 1688 +/- 571 mm(3); P = 0.003). Similarly, the MDA-MB-231 tumors in SCID mice treated with METVAN were much smaller 40 days after tumor cell inoculation than those of the vehicle-treated control SCID mice (174 +/- 29 mm(3) versus 487 +/- 82 mm(3); P = 0.002). The favorable in vivo pharmacodynamic features and antitumor activity of METVAN warrants further development of this novel oxovanadium compound as a potential new anticancer agent.

Bioavailability and pharmacokinetic features of etoposide in childhood acute lymphoblastic leukemia patients

The bioavailability and pharmacokinetic characteristics of etoposide were studied in 12 relapsed B-lineage acute lymphoblastic leukemia (ALL) patients after both intravenous (i.v.) infusion and oral administration. Following a 1 hour i.v. infusion of 50 mg/m2 etoposide, the elimination half-life ranged from 49.8 min to 509.4 min (mean +/- SD = 218.6 +/- 134.7 min), the MRT ranged from 71.8 to 734.9 min (mean +/- SD = 315.4 +/- 194.3 min) and the systemic clearance of etoposide ranged from 15.7 to 38.0 ml/min/m2 (mean +/- SD = 24.1 +/- 7.0 ml/min/m2). The AUC ranged from 2234.9 to 5427.0 microM.min) (mean +/- SD = 3827.8 +/- 1069.5 microM.min) and Vc ranged from 2026.9 to 13,505.2 ml/m2 (mean +/- SD = 6825.4 +/- 3278.5 ml/m2). The maximum plasma etoposide levels ranged from 6.0 to 28.4 microM (mean +/- SD = 13.6 +/- 6.3 microM). The bioavailability of oral etoposide was determined by comparing the AUC following i.v. infusion to the AUC following oral administration in the same patient. The overall bioavailability (mean +/- SD) was 60.6 +/- 22.4% (ranged from 17.6% to 91.2%). The elimination half-life following oral administration (mean +/- SD) was 209.8 +/- 196.3 min (ranged from 51.0 to 794.2 min). The time required to reach the maximum plasma etoposide concentration was 145.4 +/- 118.7 min (ranged from 23.7 to 396.9 min). To our knowledge, this is the first report concerning the bioavailability of etoposide in pediatric leukemia patients. All of the other pharmacokinetic properties of etoposide in pediatric B-lineage ALL leukemia patients reported here were similar to those described previously.

Successful liver transplantation in a child with biliary atresia and hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is characterized by hypoxemia in patients with severe chronic liver disease and pulmonary vasodilatation in the absence of primary cardiac or pulmonary disease. Severe hypoxemia resulting from HPS is generally considered a contraindication to liver transplantation. We describe the case of a 6-year-old girl with biliary atresia complicated with HPS who was successfully treated with liver transplantation. Cyanosis and dyspnea had initially developed at the age of 5 years. Arterial blood gas showed a PaO2 of 46.6 mm Hg on room air. The diagnosis of HPS was confirmed by contrast echocardiography, lung perfusion scan with 99mTc macroaggregate albumin, and pulmonary angiography. The lung scan revealed an intrapulmonary shunt of 24%. She underwent living donor liver transplantation and received a left lateral segment graft from her mother. One year after successful liver transplantation, she had normal arterial oxygen saturation and a normal lung scan without intrapulmonary shunting. This case demonstrates that HPS associated with end-stage liver disease is potentially curable by liver transplantation.