Anticancer effects of gemcitabine are enhanced by co-administered iRGD peptide in murine pancreatic cancer models that overexpressed neuropilin-1.

BACKGROUND: Impaired drug transport is an important factor that reduces the efficacy of anticancer agents against pancreatic cancer. Here, we report a novel combination chemotherapy using gemcitabine (GEM) and internalised-RGD (iRGD) peptide, which enhances tumour-specific drug penetration by binding neuropilin-1 (NRP1) receptor. METHODS: A total of five pancreatic cancer murine models (two cell line-based xenografts (CXs) and three tumour grafts (TGs)) were treated with either GEM (100 mg kg(-1), q3d × 4) alone or GEM plus iRGD peptide (8 µmol kg(-1)). Evaluation of NRP1 expression in xenografts and 48 clinical cancer specimens was performed by immunohistochemistry (IHC). RESULTS: We identified a subset of pancreatic cancer models that showed NRP1 overexpression sensitive to iRGD co-administration. Treatment with GEM plus iRGD peptide resulted in a significant tumour reduction compared with GEM monotherapy in CXs, but not remarkable in TGs. Potential targets of iRGD were characterised as cases showing NRP1 overexpression (IHC-2+/3+), and these accounted for 45.8% of the clinical specimens. CONCLUSIONS: Internalised RGD peptide enhances the effects of co-administered drugs in pancreatic cancer models, its efficacy is however only appreciable in those employing cell lines. Therefore, the clinical application needs to be given careful consideration.

Minimally required heat doses for various tumour sizes in induction heating cancer therapy determined by computer simulation using experimental data.

PURPOSE: Although induction heating cancer therapy (IHCT) using magnetic nanoparticles can be a promising approach to treatment-less multi-nodular cancers, the objective requirement for successful clinical application has not clearly been elucidated. We intended to define objective heat doses suitable for IHCT, especially focusing on the sizes of liver cancer nodules. MATERIALS AND METHODS: Alternating magnetic fields were applied to three human pancreatic cancer cell lines, the intercellular space of those cell pellets were filled with magnetic nanoparticles, and confirmed the cytotoxic effect of IHCT. Subsequently, the temperatures of liver cancer nodules in IHCT were simulated using a computer software program and the required heat dose for various sized tumours were determined. RESULTS: Heating the cancer cells up to 50 degrees C for 10 min was sufficient for complete cell killing and the heat dose of 1.7 W/g(tumour) is required for 10 mm tumour. Larger tumours require a smaller heat dose, e.g. 20 mm and 40 mm tumours require 0.7 W/g(tumour) and 0.6 W/g(tumour), respectively, whereas smaller tumours require large amounts of heat, e.g. 5 mm and 1 mm tumours require 5.1 W/g(tumour) and 105 W/g(tumour), respectively. CONCLUSIONS: Integrating the presently available technologies, including high-quality magnetic nanoparticles (1000 W/g(material)) and effective drug delivery systems (1-2 mg(material)/g(tumour)), treatment of a 10 mm tumour seems possible. Since treatment of smaller tumours less than 5 mm require substantial heat dose, researchers involved in IHCT should target cancer nodules of 10 mm or more, and develop a heat delivery system providing a minimum of 1.7 W/g(tumour).

Existence of Pink1 antisense RNAs in mouse and their localization.

PTEN-induced kinase 1 (PINK1), which is identified as the gene transactivated by the tumor suppressor PTEN, has been found to be one of the causative genes in Parkinson's disease (PD). In order to understand PD, rodent models containing affected Pink1 such as loss-of-function mutations have been exploited. Recently, natural antisense RNA of PINK1 has been demonstrated to be involved in the regulation of the PINK1 locus. However, no antisense RNAs of Pink1 except for human have been reported so far. Therefore, in the present study, while searching for the Pink1 antisense RNAs in mouse, we found that the antisense RNAs are transcribed from a mouse genomic region corresponding to the human region from which the antisense RNAs are produced. Further, we investigated the localization of the antisense RNAs in mouse brain using in situ hybridization; this demonstrated that the antisense RNAs were localized in the regions of brain where the Pink1 mRNA was found. In addition, the mRNA and antisense RNAs were found more densely in the hippocampus than in the other brain regions in newborn and 1-week-old mice, while those RNAs were found uniformly in the mouse brain regions of embryo day (E) 14, E17, and 8-weeks-old.

The measurement of small magnetic signals from magnetic nanoparticles attached to the cell surface and surrounding living cells using a general-purpose SQUID magnetometer.

Magnetic nanoparticles have recently been widely applied in the bio-medical field. Responding to the demand for a simple and sensitive magnetic assay system for bio-liquid samples, we employed a general-purpose superconducting quantum interference device (SQUID) magnetometer. Strips of filter paper were used as a liquid-specimen sample holder possessing a very small magnetic background signal. An aqueous solution of superparamagnetic iron-oxide nanoparticles (Resovist) was dropped in a tiny blot-like spot in the middle of the filter paper and the magnetization was measured. Magnetic moments of a dilution series of Resovist solutions versus the number of particles provided a linear graph, revealing that the magnetic moment per Resovist particle was 8.25 x 10(-17) emu. 1 x 10(5) cancer cells were incubated with Resovist, and the number of Resovist particles attached to the cell surface and surrounding a living cell was calculated to be 1.02 +/- 0.14 x 10(7) particles/cell. Our system using a commercial SQUID magnetometer should be more than enough to determine the number of magnetic nanoparticles biologically reacting with living cells, contributing to the application of magneto nanomaterials to the life-science field.

Relationship Between Stress Coping Mechanisms and Depression in Kidney Transplant Recipients.

BACKGROUND: It has been reported that transplant recipients are exposed to physical and psychosocial stresses even after transplant surgery and exhibit psychological disorders such as depression. PURPOSE: In this study, we extracted trends concerning how recipients of kidney transplants cope with stress, and we also examined how they cope with depression and its countermeasures. METHOD: We administered questionnaire surveys to 109 kidney transplant recipients. These included items on personal attributes, medical information, depression, and stress-coping type scales. Statistical analysis was performed using factor analysis and multiple regression analysis. RESULTS: Fifteen out of 109 (13.8%) were found to be high-risk patients for depression based on responses to the questionnaire using the depression scale. We extracted 2 factors of stress-coping type, namely Factor 1, "Directly coping with the problem," of patients who try to directly resolve the problem in a positive manner and Factor 2, "Stress-release while avoiding the problem," for those who relieve their feelings in response to the stress without resolving the problem itself. When multiple regression analysis was conducted with the depression scale as the dependent variable and the stress-coping factor as the independent variable, Factor 1 tended to be associated with reduced depression and Factor 2 with increased depression. CONCLUSIONS: Results showed that to improve the mental health of those who receive kidney transplants, it is necessary to examine the depression and stress-coping types of such patients at an early stage and carry out education on stress-coping, focusing on resolving the actual problem.

Localization of sense and antisense transcripts of Prdx2 gene in mouse tissues.

Recently, it has been reported that antisense RNAs are transcribed from a large number of genes in various species including human and mouse. The Prdx2 gene, which is indicated to be involved in signal transduction related to platelet-derived growth factor as well as to protection from oxidizing agents, has been shown to produce sense and antisense transcripts. To obtain clues for possible roles of Prdx2 antisense transcripts, we have performed Northern blot analysis and in situ hybridization on tissues of 8-week-old C57BL/6J mice. The Northern blot analysis revealed that major parts of sense and antisense transcripts were poly(A-)-RNA. The analysis of the fractionated RNA of fibroblasts indicated that the poly(A-)-RNA would be localized in the cytoplasm of cells. The in situ hybridization demonstrated that the sense and antisense transcripts were localized in almost the same limited areas of brain, testis, and spleen. It also revealed that the sense and antisense transcripts coexisted in Purkinje cells. In thymus and stomach, the antisense transcripts were detected, but sense transcripts were not. When tissues of BALB/c mice were examined by in situ hybridization, the observations were essentially the same as those of C57BL/6J except that it appeared that the amounts of sense and antisense transcripts in testis of BALB/c were greater than those in C57BL/6J, and that the amounts of antisense transcripts in stomach of BALB/c were much smaller than those in C57BL/6J.

A Multiple-Cell Microenvironment in a 3-Dimensional System Enhances Direct Cellular Reprogramming Into Hepatic Organoids.

OBJECTIVES: The difficulty in proliferation and availability and the rapid loss functions of primary human hepatocytes highlight the need to develop an alternative, preferably renewable source of human induced hepatocytes in regenerative medicine. Liver organoids generated on a multiple-cell microenvironment in a 3-dimensional (3D) system can provide a highly efficient solution to this issue. METHODS: Human hepatocytes were induced from fibroblasts by the lentiviral expression of FOXA3, HNF1A, and HNF4A. Together with these induced hepatocytes, human umbilical vein endothelial cells and mesenchymal stem cells in a 3D system were used to produce liver organoids. Liver-related gene and protein expression of liver organoids and induced hepatocytes were tested using a 2-dimensional (2D) system. RESULTS: Liver organoids notably increased the expression of hepatic transcription factors, marker genes, transporter genes, and liver metabolism enzyme genes, while it decreased the specific gene expression of fibroblasts. Liver organoids expressed comparable liver-specific proteins, such as ALB, AAT, and HNF4A in the 3D system. CONCLUSION: Direct reprogramming in multiple-cell microenvironments in 3D systems is more controllable and efficient than cell reprogramming in 2D systems. Liver organoids have the potential for use in disease modeling, pharmaceutical applications, and cellular transplantation.

Establishment of an animal model with side effects induced by mycophenolate mofetil and pharmacohistological analysis of them.

UNLABELLED: Mycophenolate mofetil (MMF) is used for immunosuppression after organ transplantation, but gastrointestinal side effects including diarrhea are sometimes observed with this drug. We sought to construct on animal model of diarrhea with MMF in rodents. MATERIALS AND METHODS: BALB/Cj mice, weighing 25 g received 500 mg /kg of MMF, 60 mg/kg of levofloxacin (LVFX), 1000 mg/kg of Hangeshashin-to (HST), which is traditional Kampo medicine. This cocktail was administered orally to MMF, LVFX, HST, MMF+LVFX, and MMF+LVFX+HST groups for 21 days. We measured the water content fecal collected on days 1, 4, 8, 11, 14, 18, and 21. Feces on day 21 were cultured for identification of fecal flora. Mice were sacrificed on day 21, with blood samples collected to measure mycophenolic acid (MPA) concentrations by HPLC. Jejunum, cecum, and colon were taken for histological evaluation. RESULTS: Significant weight loss of mice and increased fecal water content of were observed in MMF and MMF+LVFX but not in MMF+LVFX+HST groups. Serum MPA levels didn't differ in MMF-administered groups. Inflammatory changes in intestinal villi were observed in the cecum in MMF and MMF+LVFX groups. A change in fecal flora was observed in LVFX-administered groups. CONCLUSION: Diarrhea induced by MMF in a rodent model produced inflammatory changes in the cecum. LVFX seemed to change the activity of beta-glucuronidase in the fecal flora. HST suppressed fecal softening induced by MMF in this animal model.

MUC 1 core protein as a marker of gallbladder malignancy.

AIM: The significance of MUC 1 expression in the gallbladder tissues in relation to cancer and non-cancer disease is not well understood. The aim of this study was to clarify the significance of MUC 1 expression. MATERIALS AND METHODS: A monoclonal antibody (CA 15--3; DF 3) was applied to stain MUC 1 core protein in surgical specimens. RESULTS: MUC 1 expression is significantly higher (p<0.0001) in gallbladder cancer (69/88) compare to non-cancerous tissue, while, very trace in normal and inflammatory tissues. The expression rate was significantly lower (p<0.0001) when the cancer did not penetrate the mucosal layer than when cancers did penetrate this layer. The MUC 1 expression rate was (4/14) in T1 tumours, (11/14) in T4, (40/45) in T3, and (14/15) in T2, respectively. Every cell of normal and inflammatory mucosa, and T1 cancers had the polarized pattern. The depolarized pattern was dominant in cancer cells from the advanced tumours of T2, T3 and T4. That is, (45/74) of cancer cells from the mucosal layer and (58/74) of penetrating cancer cells in submucosal layer had the depolarized pattern. There was no significant correlation of MUC 1 expression rate and staining pattern with cancer differentiation and microscopic venous invasion. On the other hand, lymphatic vessel invasion was significantly correlated with the staining pattern but not with expression rate. CONCLUSION: MUC 1 core protein expression rate and pattern are suggesting that MUC 1 core protein would be a marker of malignant transformation of gallbladder epithelium and its depolarized expression would also be a marker of invasion of gallbladder cancer.

Backtransplantation for survival of the graft.

To assess survival of grafts after uncontrollable rejection, one performs backtransplantation from the recipient to the donor. This study investigated backtransplantation in an animal model. Hearts were transplanted heterotopically in rats. After a few days, the transplanted heart grafts were harvested from the recipients and backtransplanted to the donor strain heterotopically and a drug was administered. Cardiac grafts survived 6.2 days in the first recipients. After backtransplantation on day 5 or 6, all backtransplanted grafts survived well in the second recipients. After backtransplantation on day 7, when 4 of 5 grafts had no beat, 2 of 5 grafts recovered beating on day 3 after backtransplantation without any drug treatment. After backtransplantation on day 7, when 4 of 5 grafts had no beat, all (5 of 5 grafts) recovered beating well with the administration of FTY720 on day 3 after backtransplantation. CsA or FK506 had no effect on survival after backtransplantation. Pathological findings revealed mild cellular infiltration in the cases of FTY720 and severe necrosis in the cases of no drug, CsA, or FK506. After backtransplantation on day 8, no grafts (0 of 5 grafts in each drug) recovered beating with any drugs. These data document the possibility of backtransplantation.

Excessive portal flow causes graft nonfunction in small size liver transplantation: an experimental study in pigs.

We investigated the effects of portocaval shunt (PCS) on excessive portal flow in producing sinusoidal microcirculatory injury in small-for-size liver transplants in pigs. The posterior segment of a whole liver (25%) was transplanted orthotopically. The pigs were divided two groups: group A, graft with PCS (n = 11), and group B, graft without PCS (n = 11). The PCS was a side-to-side anastomosis of the portal vein and the inferior vena cava. In group A, eight pigs survived for more than 4 days; all pigs except for one died of graft nonfunction within 24 hours in group B. The portal flow after reperfusion decreased in group A, but increased about three times greater in group B than that before the operation (P < .01). In group B, destruction of the sinusoidal lining and bleeding in the periportal areas were observed after reperfusion, findings that were not recognized in group A. These results suggest that graft nonfunction after small-for-size liver transplantation may be attributable to excessive portal flow producing sinusoidal microcirculatory injury.

The mechanism of injury in a steatotic liver graft during cold preservation.

BACKGROUND: Fatty livers are more prone to primary nonfunction after transplantation. It is known that cell injury is strongly associated with alterations in the content and composition of membrane lipids. We assumed that plasma membrane (PM) fluidity, which is the most important property of the membrane, differed between fatty and normal livers. METHODS: The livers from obese and lean Zucker rats were flushed with cold Ringer's lactate and University of Wisconsin (UW) solution via the portal vein and preserved in cold UW solution for 24 hr. Histological examinations of electron microscopy were performed to investigate of sinusoidal lining cells (SLCs). PMs were isolated using a discontinuous density gradient of Percoll, and the lipid compositions were determined by chromatography. RESULTS: SLCs of fatty livers were markedly injured compared with control livers even after short preservation time. Moreover, many blebs were observed in the obese rats even after short preservation time. As for PM lipid composition, the cholesterol/phospholipid (PL) ratio of total PM was 0.14+/-0.03 in the obese rats and 0.21+/-0.03 in the lean rats (P<0.05). The relative proportions of polyunsaturated fatty acids among PLs in PM were 35.7+/-1.2% vs. 45.9+/-1.5% (P<0.0001). These results indicated that the fluidity of the PM in the obese rats is decreased after exposure to low temperatures. CONCLUSIONS: Our results suggest that steatotic livers from obese donors are more susceptible to cold preservation injury than livers without steatosis because of the severe deterioration of SLCs, and it is associated with PM fluidity even after short-term cold preservation.

Fragility of the electron transport chain and superoxide generation in mitochondria of the liver graft after cold ischemia.

BACKGROUND: After cold ischemia, electrons transferred in the electron transport chain may leak out of the mitochondria in proportion to the deterioration of mitochondrial oxidative phosphorylation. This seems to be one major cause of the lipid peroxidation that occurs mainly in the hepatocytes at reperfusion in liver transplantation. To examine this hypothesis, we investigated superoxide generation and the amount of oxidative phosphorylation in the mitochondria isolated from rat livers after cold preservation. METHODS: Rat liver was preserved in University of Wisconsin solution at 4 degrees C for 24 hr. The mitochondrial fraction was prepared, and the amount of ATP synthesis and superoxide generation was investigated. Superoxide generation in the electron transport chain of submitochondrial particles was also measured by a chemiluminescence recorder. RESULTS: The amount of ATP synthesis was significantly decreased after 12 hr of cold preservation. In the whole mitochondria, superoxide production in the presence of succinate was approximately 1/2000 to 1/3000 less than that observed in the submitochondrial particles at any determination point, and superoxide production was not affected by cold preservation. In the presence of antimycin A, superoxide production in the mitochondria after 18 hr of preservation increased significantly. CONCLUSION: These results indicate that the electron transfer in the complex III of the mitochondrial membrane becomes leaky after long periods of cold ischemia, but that leakage of superoxide anion did not increase, although the mitochondrial respiratory phosphorylation was deteriorated. We conclude that superoxide through the mitochondrial membrane cannot cause lipid peroxidation in hepatocytes at reperfusion even after a long period of cold ischemia.

Assessment of liver graft function after cold preservation using 31P and 23Na magnetic resonance spectroscopy.

We investigated the functional damages of the cytoplasm and the cell membrane of liver grafts in male Wister Kyoto rats after 24-hr and 48-hr cold preservations using the University of Wisconsin solution in vitro. Fructose (10 mM) or NH4Cl (50 mM) was added to the perfusate, and synthesis of fructose-1-phosphate (F-1-P) and Na- and H-ion transports through the cell membrane were evaluated by magnetic resonance spectroscopy (MRS), 31P-MRS and 23Na-MRS. After 30 min of reperfusion, beta-ATP/(inorganic phosphate: Pi) of the 48-hr preserved group was significantly lower than the control group and the 24-hr preserved group. The changes of F-1-P in the control group and the 24-hr preserved group were almost the same, but F-1-P synthesis was lower in the 48-hr preserved liver than those of the other groups. Intracellular pH began to drop after the cessation of NH4Cl loading, and then it recovered to the preloading level. At the same time Nain+ was increased in the control group. However, in the other two groups, the increasing rates of Nain+ were lower, and the recoveries of Nain+ were less. In conclusion, the function of cell membrane was more fragile than that of mitochondria and cytoplasmic sugar metabolism in the liver graft.

Elimination of Kupffer cells and nafamostat mesilate rinse prevent reperfusion injury in liver grafts from agonal non-heart-beating donors.

BACKGROUND: We hypothesized that microcirculatory disturbance was an obstacle to liver transplantation (LTx) from non-heart-beating donors (NHBDs) and that it was attributed mainly to a deterioration of sinusoidal endothelial cells (SECs) and sinusoidal narrowing. This study was designed to examine porcine orthotopic LTx using livers obtained from pretreated agonal NHBDs, and to determine whether the maintenance of the liver microcirculation would result in successful LTx from agonal NHBDs. METHODS: Pigs were allocated to five groups: (i) control group; (ii) NM group, in which grafts were rinsed with nafamostat mesilate (NM) rinse; (iii) LD group, in which Kupffer cells in grafts were eliminated by liposome-encapsulated dichloromethylene diphosphonate (L-DMDP); (iv) LDNM group, in which grafts pretreated with L-DMDP were rinsed with NM rinse; (v) heart-beating donor (HBD) group. In all groups, but the HBD group, the livers were pretreated with FK506 and prostaglandin I2 analogue, and were preserved in University of Wisconsin solution after cardiac arrest. Thereafter orthotopic LTx was performed. RESULTS: After reperfusion, it was histologically demonstrated that elimination of Kupffer cells prevented SECs deterioration and NM rinse prevented sinusoidal narrowing. The hepatic energy charge recovered in all groups except the control group. In the LDNM group, three of four recipients survived more than 7 days. CONCLUSIONS: For a successful LTx from agonal NHBDs, it is important to prevent microcirculatory disturbance caused by SEC deterioration and sinusoidal narrowing after reperfusion. Combination therapy consisting in the elimination of Kupffer cells and NM rinse prevented primary graft non-function in liver grafts from agonal NHBDs.

Disorder of bile acid metabolism in children with short bowel syndrome.

The profile of fecal bile acids was examined in 13 children with short bowel syndrome; 7 of the 13 did not have diarrhea and the other 6 had intractable diarrhea. In children without diarrhea, no severe fat malabsorption was recognized, and the content of total bile acids in the feces was within the normal range or slightly higher. The ratio of primary to total bile acids showed various patterns. In children with intractable diarrhea, in contrast, fat malabsorption was observed and the fecal content of total bile acids in these patients was more than ten times higher than that of the control group, primary bile acids accounting for more than 95% of the total bile acids and taurine- or glycine-conjugated bile acids for 10%. In the children with intractable diarrhea, the values for the D-xylose absorption test were lower than the normal range. These results suggested that, in children with short bowel syndrome with diarrhea, the loss of bile acids was strongly associated with a decrease in the actual absorptive surface area of the residual small intestine, and the growth of the normal bacterial flora was disturbed in the residual intestine. Some children with or without diarrhea also had hyper bile acidemia. Ursodeoxycholic acid was not effective for the treatment of hyper bile acidemia or fat malabsorption.

New technique for gene transfection using laser irradiation.

BACKGROUND: We have developed a gene transfection system using laser beams. The principle of this procedure is that a small hole is made in a cell membrane by pulse laser irradiation, and a gene contained in a medium is transferred into the cytoplasm through the hole. This hole disappears immediately with the application of laser irradiation of the appropriate power. METHODS: A pulse-wave Nd:YAG laser with a wavelength of 355 nm was used to make a hole in a cell membrane. To trap a cell, a continuous-wave Nd:YAG laser with a wavelength of 1015 nm was used. Plasmids that encode the enhanced green fluorescent protein (EGFP) gene were contained in a medium and transferred to HuH-7 and NIH/3T3 cells with pulse laser irradiation. We evaluated transfection efficiency on the basis of the number of cells that expressed EGFP. Stimulatory protein 2 cells in suspension were fixed using a trapping laser and the neomycin-resistance gene was transfected by pulse laser irradiation. We examined cell proliferation in the selection medium. RESULTS: Cells that expressed EGFP were recognized in the group that was irradiated by pulse laser. No cells expressed EGFP without irradiation. Transfection efficiency was approximately 10% at a plasmid concentration of 10.0 microg/mL. At concentrations greater than 20 microg/mL, the transfection rate reached a plateau. We also successfully transfected neomycin-resistance genes to cells floating in suspension after fixation that was achieved with trapping laser irradiation. CONCLUSIONS: This method enables us to transfect targeted cells, ie, cells in suspension as well as attached cells, with a simple technique that does not involve harmful vectors. The present method is very useful for gene transfection in cellular biotechnology.

A chemiluminescent assay for hydroperoxide level of phosphatidylcholine hydroperoxide fraction purified by two Sep-Pak cartridges in biological samples.

A chemiluminescent assay for hydroperoxide level of phosphatidylcholine hydroperoxide (PCOOH) fraction purified from biological samples was presented. This method utilized of two Sep-Pak cartridges. A lipid soluble fraction was isolated from each homogenized tissue or blood by Folch's method. The mixture of phosphatidylcholine (PC) and PCOOH was separated from the lipid soluble fraction by a Sep-Pak silica cartridge. A Sep-Pak tC18 cartridge made complete separation of both PCOOH and PC possible. The hydroperoxide level of PCOOH fraction was quantified by the reaction with ferrous ion using 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo[1,2-a]pyrazin++ +-3-one as a chemiluminescent dye. The mixture of positional isomers, 1-hexadecanoyl-2-[9, or 10-hydroperoxyl octadecanoyl]-sn-glycero-3-phosphocholine was used as an authentic standard. The good recovery rate for authentic PCOOH of 87.1 +/- 11.6% (mean +/- S.E., n = 4) was obtained by using two Sep-Pak cartridges. Linear calibration curve was obtained in the range from 2.5 to 20 nmol, and the detection limit of the standard was 10 pmol (signal-to-noise ratio > 3). This method was applied to the investigation of the lipid peroxidation induced by reperfusion of the liver with cold preservation, mimicking liver transplantation in rats. The effect of liposome-encapsulated dichloromethylene diphosphonate (LEDD), which eliminate of Kupffer cells to prevent the generation of oxygen radicals on the lipid peroxidation, was compared with the untreated group as a control. After 1 h reperfusion at 37 degrees C the hydroperoxide level obtained the liver without preservation in the untreated group was 12.4 +/- 2.4 nmol/100 mg lipid (n = 4) and levels increased significantly by prolongation of the preservation time. On the other hand, the hydroperoxide level in the LEDD treated group did not change up to 24 h preservation. These results suggest that this improved assay for hydroperoxide level of PCOOH fraction in biological samples can be applied to investigations involving lipid peroxidation because of its simplicity and accuracy.

Species difference in mechanisms of D-xylose absorption by the small intestine.

Comparisons were made for the ability of D-xylose to evoke changes in the transepithelial potential difference upon its addition to the mucosal solution between guinea pig and rat small intestines. Also, Na+-dependence of D-xylose influx from the mucosal solution into epithelial cells, and the phlorizin-sensitivity of the influx, were compared between these animals. In guinea pig intestine, the sugar caused an immediate and sustained increase in the transmural potential difference, and this potential increment was completely abolished by phlorizin. In contrast, the sugar did not cause any electrical changes in the rat small intestine. The influx of D-xylose across the mucosal border was Na+-dependent and phlorizin-sensitive in guinea pigs, while it was Na+-independent and phlorizin-insensitive in rats. The results indicate that there is a qualitative difference in the mode of transport of D-xylose between guinea pigs and rats.

Analysis of donor criteria for the prediction of outcome in clinical liver transplantation.

The results of 219 orthotopic human liver transplants performed during 1985 at the University of Pittsburgh were reviewed to determine whether donor parameters could be used to predict the quality of early graft function. Multivariate discriminant analysis demonstrated that traditional parameters of donor assessment are unreliable predictors of poor graft function. Furthermore, 56% of the donors considered poor by conservative selection criteria produced livers with good early posttransplant function. Survival of recipients of primary allografts from donors rated poor was no different than survival of recipients of allografts from donors rated good.