Influence of splenomegaly on aortic and liver parenchymal CT numbers during contrast-enhance CT in patients with cirrhosis.

INTRODUCTION: To compare CT (computed tomography) values for enhancement of the abdominal aorta and liver parenchyma during dynamic contrast enhancement (CE) CT in cirrhotic patients with and without splenomegaly (SM). METHODS: We considered 258 patients (83 males and 46 females for the splenomegaly group, and 83 males and 46 females for the control group) for this retrospective study. We measured CT values in the abdominal aorta and hepatic parenchyma during the hepatic arterial (HAP) and portal venous (PVP) phases. The aortic CE at HAP and the hepatic parenchymal CE at PVP were compared between the two groups. For success rate of scans, we also calculated the optimal CE rates (>280 HU in the abdominal aorta and >50 HU in the hepatic parenchyma) for each group. RESULTS: In the SM group, the CE for abdominal aorta was decreased during the aortic phase for a dynamic CE-CT (p < 0.05). When evaluating the success rates, they were found to be 65.1 % and 58.9 % in the SM group and 81.4 % and 72.3 % in the non-SM group (p < 0.05). CONCLUSION: The success rate of scans and CE for the abdominal aorta during the aortic phase exhibited a significant decrease during dynamic CE-CT scans on patients with SM. Patients with SM may have reduced diagnostic ability with typical contrast injection protocols. IMPLICATIONS FOR PRACTICE: It may be necessary to change the injection rates and contrast medium volume during CE-CT depending on the presence or absence of SM.

Comparison of formation of thiolactones and active metabolites of prasugrel and clopidogrel in rats and dogs.

Prasugrel and clopidogrel are antiplatelet prodrugs that are converted to their respective active metabolites through thiolactone intermediates. Prasugrel is rapidly hydrolysed by esterases to its thiolactone intermediate, while clopidogrel is oxidized by cytochrome P450 (CYP) isoforms to its thiolactone. The conversion of both thiolactones to the active metabolites is CYP mediated. This study compared the efficiency, in vivo, of the formation of prasugrel and clopidogrel thiolactones and their active metabolites. The areas under the plasma concentration versus time curve (AUC) of the thiolactone intermediates in the portal vein plasma after an oral dose of prasugrel (1 mg kg(-1)) and clopidogrel (0.77 mg kg(-1)) were 15.8 +/- 15.9 ng h ml(-1) and 0.113 +/- 0.226 ng h ml(-1), respectively, in rats, and 454 +/- 104 ng h ml(-1) and 23.3 +/- 4.3 ng h ml(-1), respectively, in dogs, indicating efficient hydrolysis of prasugrel and little metabolism of clopidogrel to their thiolactones in the intestine. The relative bioavailability of the active metabolites of prasugrel and clopidogrel calculated by the ratio of active metabolite AUC (prodrug oral administration/active metabolite intravenous administration) were 25% and 7%, respectively, in rats, and 25% and 10%, respectively, in dogs. Single intraduodenal administration of prasugrel showed complete conversion of prasugrel, resulting in high concentrations of the thiolactone and active metabolite of prasugrel in rat portal vein plasma, which demonstrates that these products are generated in the intestine during the absorption process. In conclusion, the extent of in vivo formation of the thiolactone and the active metabolite of prasugrel was greater than for clopidogrel's thiolactone and active metabolite.

Functional impairment of renal afferent arteriolar voltage-gated calcium channels in rats with diabetes mellitus.

Experiments were performed to test the hypothesis that diabetes mellitus is associated with impaired afferent arteriolar responsiveness to opening of voltage-gated calcium channels. Diabetes was induced by injection of streptozocin (65 mg/kg, i.v.) and insulin was administered via an osmotic minipump to achieve moderate hyperglycemia. Sham rats received vehicle treatments. 2 wk later, the in vitro blood-perfused juxtamedullary nephron technique was used to allow videomicroscopic measurement of afferent arteriolar contractile responses to increasing bath concentrations of either Bay K 8644 or K+. Baseline afferent arteriolar diameter in kidneys from diabetic rats (26.4+/-1.2 microm) exceeded that of Sham rats (19.7+/-1.0 microm). Bay K 8644 evoked concentration-dependent reductions in afferent diameter in both groups of kidneys; however, arterioles from Sham rats responded to 1 nM Bay K 8644 while 100 nM Bay K 8644 was required to contract arterioles from diabetic rats. The EC50 for K+-induced reductions in afferent arteriolar diameter was greater in diabetic kidneys (40+/-4 mM) than in kidneys from Sham rats (28+/-4 mM; P < 0.05). In afferent arterioles isolated by microdissection from Sham rats and loaded with fura 2, increasing bath [K+] from 5 to 40 mM evoked a 98+/-12 nM increase in intracellular Ca2+ concentration ([Ca2+]i). [Ca2+]i responses to 40 mM K+ were suppressed in afferent arterioles from diabetic rats (delta = 63+/-5 nM), but were normalized by decreasing bath glucose concentration from 20 to 5 mM. These observations indicate that the early stage of insulin-dependent diabetes mellitus is associated with a functional defect in afferent arteriolar L-type calcium channels, an effect which may contribute to suppressed afferent arteriolar vasoconstrictor responsiveness and promote glomerular hyperfiltration.

Prediction of response to and actual outcome of chlorpromazine treatment in schizophrenic patients.

A blink controlled study evaluated the prediction of response to chlorpromazine treatment in 37 schizophrenics on the basis of actual outcomes. Prior to the initiation of treatment, blood samples were taken three hours after a dose of 50 mg of chlorpromazine for the analyses of the drug and its metabolites. The chlorpromazine therapy was then begun and continued for three months. The results agreed with our previous conclusion that patients who showed high levels of the metabolites after a single dose of chlorpromazine tended to have poor clinical improvement with chlorpromazine and that the responders showed the opposite pattern. The predictability of response to chlorpromazine therapy is significantly high in the patients with very low or high levels of the metabolites. However, this is useful at best in 46% of the subjects studied.

Adverse reactions to lipiodol ultra fluid: report of an accidental case.

A 25-year-old Japanese woman experienced pulmonary edema, shock, encephalopathy and silent pancreatitis after hysterosalpingography using lipiodol ultra fluid, because the contrast media flowed directly into the blood stream from endometrium injured by several curettages for termination of pregnancy. Total iodine concentrations in plasma and urine decreased exponentially and their half-life was 16.12 and 13.04 days, respectively. Clear correlations were observed between the iodine concentration in plasma and the amelioration of both electroencephalogram and neuropsychic abnormalities. Adverse reactions of oil-soluble contrast media are also discussed.

Isolation and expression in Escherichia coli of a cDNA clone encoding porcine pancreatic elastase.

We have cloned a DNA that is complementary to the messenger RNA that encodes porcine pancreatic elastase 1 from pancreas using rat pancreatic elastase 1 cDNA as a probe. This complementary DNA contains the entire protein coding region of 798 nucleotides which encodes an elastase of 266 amino acids, and 22 and 136 nucleotides of the 5' and 3'-untranslated sequences. When this deduced amino acid sequence was compared with known amino acid sequences, a carboxy-terminal 240 amino acids long peptide was found to be identical with a mature form of porcine pancreatic elastase 1, except for two amino acids. The porcine enzyme contains the same number of amino acid residues as the rat enzyme, and their amino acid sequences are 85% homologous. Taking the above findings together, we conclude that the cloned cDNA encodes a mature enzyme of 240 amino acids including a leader and activation peptide of 26 amino acids. We expressed the cloned porcine pancreatic elastase 1 cDNA in E. coli as a lac-fused protein. The resulting fused protein showed enzymatic activity and immunoreactivity toward anti-elastase serum.

Sodium balance and hypertension in obese and fatty rats.

To investigate the role of sodium in obesity induced hypertension, Wistar fatty rats (WFR) were employed. This rat has the following characteristics: (1) hyperglycemia, (2) hyperinsulinemia, and (3) hypertriglycemia. Four percent sodium chloride with constant amount of food intake was administered to these rats from 8 to 16 weeks. During this period, body wt, food intake, water consumption, urine volume, systolic blood pressure, urinary excretion of sodium and potassium, urinary albumin excretion, plasma sodium and potassium, and plasma glucose and immunoreactive insulin (IRI) were measured before, and twice more during eight weeks. No remarkable changes were observed in plasma glucose level during these periods between the two groups. On the other hand, in group 1 IRI significantly increased compared with group 2. Mean blood pressure was increased from 110 +/- 5 to 130 +/- 8 mm Hg (P < 0.01). To ascertain whether this salt sensitivity relates to the abnormalities in pressure-natriuresis responses, the pressure-natriuresis (P-N) was characterized. The P-N curve in WFR was shifted to the right and its slope was flattened compared to its control Wistar lean rats. In conclusion, an excess of dietary sodium intake may contribute to an elevation of blood pressure in Wistar fatty rat with hyperglycemia and hyperinsulinemia. This salt sensitivity may change the abnormal pressure-natriuresis responses.

Effects of renal sorbitol accumulation on urinary excretion of enzymes in hyperglycaemic rats.

We studied the effects of epalrestat, a specific inhibitor of aldose reductase, on renal sorbitol accumulation and the resulting urinary enzyme excretion in hyperglycaemic rats. The activities of proximal tubule-derived enzymes such as N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), gamma-glutamyltranspeptidase (GGT) and dipeptidyl aminopeptidase IV (DAPIV) in urine were determined in five groups of male Wistar rats (each n = 7): (a) 0.9% saline-loaded, (b) 10% glucose-loaded, (c) 10% glucose-loaded with epalrestat pretreatment, (d) 10% mannitol-loaded and (e) 10% mannitol-loaded with epalrestat pretreatment. Epalrestat was given mixed in chow at a dose of 50 mg/kg body weight. Urinary NAG, AAP, GGT and DAPIV activities were significantly increased (P<0.005, P<0.05, P<0.01, P<0.01, respectively) by the induction of hyperglycaemia. In contrast, enzyme excretion was not increased in the mannitol- or saline-loaded groups. Pre-treatment with epalrestat completely prevented the increased urinary excretion of NAG, AAP and GGT. At the end of the infusion study, renal cortical glucose concentrations of the glucose-loaded groups with and without epalrestat pretreatment were approximately fivefold higher than those of the mannitol- or saline-loaded groups (P<0.005 each). Renal cortical sorbitol concentrations of the glucose-loaded group was also approximately twofold higher than those of the mannitol- or saline-loaded groups (P<0.01 each). However, in the group that received both glucose and epalrestat, renal cortical sorbitol concentration was not increased. These results suggest that accumulation of intracellular sorbitol leads to proximal tubular cell dysfunction and abnormal enzymuria.

Massive culture of human liver cancer cells in a newly developed radial flow bioreactor system: ultrafine structure of functionally enhanced hepatocarcinoma cell lines.

With a view to initiating clinical trials, cell morphology and function for a newly developed artificial liver support system employing highly functional human liver cell line, FLC-7, cultured in a radial flow bioreactor were compared to cells grown in a conventional monolayer culture. The radial flow bioreactor consists of a vertically extended cylindrical matrix comprised of porous glass bead microcarriers through which liquid medium flows from the periphery in toward the central axis generating a beneficial concentration gradient of oxygen and nutrients, while preventing excessive shear stresses or buildup of waste products. The three-dimensional culture system supports high-density (1.1 x 10(8) cells/ml-matrix), large scale cultures (4.4 x 10(10) cells/400 ml-bioreactor) with long-term viability. Scanning and transmission electron microscopy (SEM and TEM) revealed that cells cultured in a monolayer system were flattened and extended with numerous cytoplasmic projections. Cells in the three-dimensional culture were spherical and covered with microvillilike processes resembling liver cells in vivo. The cells were solidly attached on the surfaces and within the pores of the microcarriers in highly dense colonies. The spherical cells remained in close contact with adjacent cells, while circulation of liquid medium flowed freely through spaces between cells. FLC-7 cells produced albumin at a rate of 6.41 micrograms/24 h/10(6) cells. Alpha-fetoprotein (AFP) production dropped nearly threefold in comparison to monolayer cultures. Results demonstrated that the new artificial liver support systems (ALSS) provides a superior three-dimensional culture environment that allows cells to perform at naturally functioning levels.

[Quality control and cytogenetic analysis of human pre-embryos fertilized and cultured in vitro].

For the purpose to evaluate in vitro culture conditions of human preembryos, the efficacy of conventional culture and co-culture systems on embryonic development and genetic disorders was studied. Firstly, the development of cultured mouse embryos grown in standard media (Whitten's, GPM, HFT and Ham F10) or in HFT medium with different helper cell layers was compared. Embryonic growth was substantially reduced during in vitro culture, demonstrably by impaired cell proliferation, compared with in vivo controls. In in vitro fertilization and culture condition, SCEs of blastocysts were significantly increased. Development in co-culture with the feeder layers was notably better than in standard media. These results suggest that human preembryos could be rescued by the use of helper cells. Increased developmental rates and the cell numbers of blastocysts were the most evident morphological features of human preembryos that developed in co-culture with uterine luminal epithelial cells. However mosaicism may be caused by in vitro culture conditions and its onset may indicate when a disturbance in the embryonic development has occurred. It is advisable to perform further research into the mechanism of feeder cell-embryo interaction for understanding the optimal conditions of embryonic development in vitro.

Duodenum-preserving resection of the head of the pancreas--modified procedures and long-term results-.

BACKGROUND/AIMS: Relief of chronic pancreatitis can be accomplished surgically or with medication. Surgical treatment of pancreatitis should preserve the endocrine and exocrine function of the pancreas. This paper details the results of our modified procedure for resecting the head of the pancreas. The advantage of this procedure is small resection, preservation of endocrine and exocrine function, complete relief of pain by the pancreatic duct drainage and maintenance of function of the duodenum and bile duct. PATIENTS AND METHODS: Duodenum-preserving resection of the pancreatic head with denervation of the body and tail of the pancreas was performed in 41 patients with severe chronic pancreatitis. RESULTS: Mortality after a median follow-up period of 36 months was 2.4%. Complete relief or alleviation of pain were found in 92% of patients and any other patients of recurrent pain due to postoperative pancreatitis was not found. Eighty-seven percent of patients had maintained more than preoperative body weight. Postoperative glucose tolerance was unchanged in 88% of patients. After long-term follow-up postoperative exocrine function had been maintained at preoperative condition. CONCLUSIONS: Our procedure can maintain endocrine and exocrine function of the pancreas, relieve pain well and prevent pain due to recurrent pancreatitis.

High density culture of immortalized liver endothelial cells in the radial-flow bioreactor in the development of an artificial liver.

Liver endothelial cells are important components of the tissue along the hepatic sinusoid. They are responsible for microcirculation in the liver and scavenger functions. It would therefore be important to include these cells in any hybrid type of artificial liver in addition to hepatocytes. However, it is difficult to culture these cells in vitro. The development of a liver endothelial cell line, which maintains the characteristics of the primary culture, would thus be of great benefit in the development of an artificial liver. In the present study we established immortalized liver endothelial cells from the liver of an H-2Kb-tsA58 transgenic mouse, which harbors the SV40 TAg gene. Hepatic sinusoidal cells isolated from H-2Kb-tsA58 mouse proliferated in the presence of gamma-interferon at 33 degrees C. Four clones were established, out of which clone M1 had the highest amounts of PGI2 production, as well as plasminogen activator activity and internalized acetylated low density lipoprotein. On culture dishes the M1 cells grew individually and spread. Sieve plates on the cell surface were not readily visible, but small pores were detected under electron microscopic observation. These results suggest that M1 clone cells originated from liver endothelial cells. Moreover it was possible to culture the immortalized liver endothelial cells in a radial-flow bioreactor for 5 days, with a maximum 6-keto prostaglandin F1alpha production of 25 microg per day. This suggests that immortalized liver endothelial cells and a radial-flow bioreactor can prove useful tools in the development an artificial liver.

Elution profiles and molecular weights of placental cystine aminopeptidase in animals.

Gel filtration was performed for cystine aminopeptidase (CAP) [EC 3.4.11.3] on full term placental extracts from human, cynomolgus monkey, dog, goat, pig and horse. The enzymatic profiles of CAP were examined and compared with that of CAP in pregnancy plasma on the basis of inhibitory effects. Elution profiles of placental extracts exhibited 2 CAP activity peaks in human and pig, 3 peaks in cynomolgus monkey, dog and goat, and 4 peaks in horse. The molecular weights of placental CAP that showed identical inhibitory effects to that of pregnancy plasma CAP were estimated to be approximately 325,000 in human, 350,000 in the cynomolgus monkey, 140,000 in the dog, 140,000 in the goat, 128,000 in the pig, and 115,000 in the horse. These molecular weights tended to decrease in accordance with the increase of barrier layers present between maternal blood and placental syncytiotrophoblasts in which CAP is synthesized.

Placental and plasma cystine aminopeptidase in pregnant animals.

The placental and plasma cystine aminopeptidase (CAP) in pregnant animals was examined on stability after the treatment with L-methionine, ethylene diamine tetra-acetic acid (EDTA) and heat. Inhibitory effects of these treatments on enzyme activities were different among CAPs from the animal species, however, significant correlation in those effects between placental and plasma CAPs was observed. These results suggested that plasma CAP might reflect placental CAP and seemed to be available for estimating maternal gestational conditions.

Development-inhibiting activity of some tropical plants against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae).

Thirteen tropical plants were evaluated for development-inhibiting activity against Sitophilus zeamais. The bioassays were carried out by incorporating seeds or leaves at various dose levels into an artificial diet for the test insect. It was found that seeds of Basella alba and leaves of Operculina turpethum and Calotropis gigantea were potent in delaying development and in reducing adult emergence, and hence the capacity for population increase. At 0.5% concentration, adult emergence in tests with B. alba, O. turpethum and C. gigantea was reduced by 62, 95 and 70%, respectively. In B. alba and C. gigantea, the development periods were 2.2 and 1.8 times those in the control and the capacities for increase/day were only 0.0324 and 0.0328 compared with 0.1004 in the control. B. alba, O. turpethum and C. gigantea were active at concentrations as low as 0.01, 0.05 and 0.1%. The potential of these materials in insect pest management is discussed.