Effect of phosphodiesterase III inhibitor (Olprinone) on thoracic duct lymph flow in anesthetized sheep with experimentally induced heart failure by endothelin-1

We investigated the short-term effects of a phosphodiesterase III inhibitor (Olprinone) on hemodynamics and thoracic duct lymph flow in anesthetized open-chest sheep with heart failure induced by endothelin-1 (cardiogenic shock). Ultrasound transit-time flow probes were attached to the thoracic duct, the ascending aorta and the renal artery. Arterial, pulmonary and central venous pressures were monitored. Endothelin-1 was infused intravenously at a dosage that reduced cardiac output to 50% or more of baseline (n=11). The effects of Olprinone were examined (n=5) by intravenous infusion after endothelin-1 administration. Other sheep (n=6) were used as controls. Olprinone significantly increased cardiac output that had been decreased by endothelin-1 and further increased thoracic duct flow that had been increased by endothelin-1. Increased arterial and pulmonary pressures induced by endothelin-1 administration were rapidly decreased by Olprinone. Renal arterial flow and central venous pressure were, however, unchanged by Olprinone. Overall, Olprinone acutely improved experimental cardiogenic shock (heart failure) induced by endothelin-1, and maintained thoracic duct lymph flow at a high level after endothelin-1 administration.

Analysis of host response to hepatectomy by simultaneous measurement of cytokines in the portal vein, caval vein and radial artery

We analysed the host response to hepatectomy by simultaneous measurement of various cytokines and their antagonists in the portal vein, caval vein and radial artery in 10 patients with hepatocellular carcinoma. Concentrations of tumour necrosis factor-alpha (TNF), interleukin (IL) 1 beta, IL-2, IL-6, IL-10, soluble TNF receptor type I (sTNF-R), soluble IL-2 receptor (sIL-2R), IL-1 receptor antagonist (IL-1ra), soluble CD14 (sCD14) and endotoxin were determined just before and 1 h after hepatectomy. The values of IL-6, sTNF-R and IL-1ra were significantly increased after hepatectomy at each sampling site. In contrast, the levels of sIL-2R and sCD14 after hepatectomy were significantly decreased, and the levels of IL-1 beta, IL-2 and IL-10 were below the detection limits. Differences in cytokine concentrations between sampling sites revealed that the surgical stress of hepatectomy induced significant IL-1ra production in the liver and sTNF-R and IL-6 production in the lungs. These results suggest that hepatic resection is followed by the production of cytokine antagonists, such as IL-1ra, sTNF-R and IL-6, which could represent an important regulatory mechanism against surgical stress.

Prognostic significance of the labeling of Adnab-9 in pancreatic intraductal papillary mucinous neoplasms

BACKGROUND

Pancreatic intraductal papillary mucinous neoplasms (IPMN), morphologically resembling colonic adenomas, often have an indefinable malignant potential. We used a monoclonal antibody (MAb) raised against colonic adenomas, Adnab-9, to identify patients with a better prognosis.

METHODS

We assessed Adnab-9-labeled sections of these neoplasms from 50 patients, 13 pancreatic adenocarcinomas, and 32 colonic adenomas using standard immunohistochemical techniques.

RESULTS

26% of the IPMNs labeled with Adnab-9 as compared to 0% of pancreatic ductal cancers or surrounding benign tissues, (p < 0.001) and 53% of adenomas (p < 0.025). Labeling in IPMNs was usually seen in the noninvasive epithelium suggesting that Adnab-9 is a premalignant marker in these lesions. Labeling of invasive IPMN's identified a group of patients with a superior overall survival (p = 0.027).

CONCLUSION

Adnab-9 labeling-characteristics appear similar for both IPMNs and adenomatous polyps, suggesting that they are analogous lesions. Adnab-9 labeling may also be a useful prognostic marker for invasive intraductal papillary mucinous neoplasms.

Increased heme oxygenase-1 gene expression in the livers of patients with portal hypertension due to severe hepatic cirrhosis

Surgical bleeding associated with splanchnic hyperaemia due to portal hypertension complicates the anaesthetic management of hepatic transplantation. Although the mechanism(s) of portal hypertension are not fully understood, carbon monoxide, a product of the heme oxygenase (HO) reaction, is thought to be one of the endogenous vasodilators in the liver. In this study, the expression of mRNA encoding inducible HO isozyme (HO-1) in the livers of patients with portal hypertension undergoing hepatic transplantation was determined in comparison with those without portal hypertension. HO-1 mRNA levels were significantly greater in the portal hypertension group than in the group without portal hypertension. In contrast with HO-1, the gene expression of non-specific delta-amino-levulinate synthase (ALAS-N), which is down-regulated by heme in the liver, was the same in both groups. These results suggest that HO-1 is up-regulated through heme-independent stimuli according to the development of portal hypertension, and that induced HO-1 plays a pathophysiological role in portal hypertension through carbon monoxide production.

Coronary smooth muscle differentiation from proepicardial cells requires rhoA-mediated actin reorganization and p160 rho-kinase activity

We recently reported that the first detectable expression of SMC-specific proteins during coronary smooth muscle cell (CoSMC) differentiation from isolated proepicardial cells was restricted to cells undergoing epithelial-to-mesenchymal transformation (EMT). The objectives of this study were to examine more closely the relation between actin cytoskeletal rearrangements and serum response factor (SRF)-dependent transcription, and to specifically test whether rhoA-GTPase signaling is required for CoSMC differentiation. We report here that PDGF-BB stimulates EMT and promotes SRF-dependent expression of SMC marker genes calponin, SM22alpha, and SMgamma(actin) (SMgammaA) in proepicardial cells. C3 exoenzyme or rhoGDI, inhibitors of rhoA signaling, blocked PDGF-BB-induced EMT, prevented actin reorganization into stress fibers, and inhibited CoSMC differentiation. Incubation with the selective p160 rho-kinase (p160RhoK) inhibitor Y27632 (RKI) blocked EMT, prevented the appearance of calponin and SMgammaA-positive cells, and abolished expression and nuclear localization of SRF. To test the role of RhoK signaling for CoSMC differentiation in vivo, quail proepicardial organs (PEOs) were pretreated with RKI or vehicle and then grafted into age-matched host chick embryos to produce a chimeric epicardium. The ability of grafted cells to participate in coronary vessel formation was monitored by staining with antibodies for quail cell nuclear antigen and SMC marker proteins. Proepicardial cells pretreated with RKI failed to form CoSMCs in vivo. Time course studies traced this deficiency to a failure of epicardial-derived mesenchymal cells to migrate into or survive within the myocardium. In summary, these data point to important roles for rhoA-RhoK signaling in molecular pathways controlling cytoskeletal reorganization, SRF-dependent transcription, and cell survival that are required to produce CoSMCs from proepicardial cells.

Constituents of ophiuroidea. 1. Isolation and structure of three ganglioside molecular species from the brittle star Ophiocoma scolopendrina

Three ganglioside molecular species, OSG-0 (1), OSG-1 (2), and OSG-2 (3) have been obtained from the polar lipid fraction of the chloroform/methanol extract of the brittle star Ophiocoma scolopendrina. The structures of these gangliosides have been determined on the basis of chemical and spectroscopic evidence as 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (1), 1-O-[8-O-sulfo-(N-acetyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyll-ceramide (2) and 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->8)-(N-acetyl- and N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (3). The ceramide moieties were composed of heterogeneous unsubstituted fatty acid, 2-hydroxy fatty acid and phytosphingosine units. Compounds 2 and 3 represent new ganglioside molecular species.

Electroporation in a model of cardiac defibrillation

INTRODUCTION

It is known that high-strength shock disrupts the lipid matrix of the myocardial cell membrane and forms reversible aqueous pores across the membrane. This process is known as "electroporation." However, it remains unclear whether electroporation contributes to the mechanism of ventricular defibrillation. The aim of this computer simulation study was to examine the possible role of electroporation in the success of defibrillation shock.

METHODS AND RESULTS

Using a modified Luo-Rudy-1 model, we simulated two-dimensional myocardial tissue with a homogeneous bidomain nature and unequal anisotropy ratios. Spiral waves were induced by the S1-S2 method. Next, monophasic defibrillation shocks were delivered externally via two line electrodes. For nonelectroporating tissue, termination of ongoing fibrillation succeeded; however, new spiral waves were initiated, even with high-strength shock (24 V/cm). For electroporating tissue, high-strength shock (24 V/cm) was sufficient to extinguish ongoing fibrillation and did not initiate any new spiral waves. Weak shock (16 to 20 V/cm) also extinguished ongoing fibrillation; however, in contrast to the high-strength shock, new spiral waves were initiated. Success in defibrillation depended on the occurrence of electroporation-mediated anodal-break excitation from the physical anode and the virtual anode. Some excitation wavefronts following electrical shock used a deexcited area with recovered excitability as a pass-through point; therefore, electroporation-mediated anodal-break excitation is necessary to block out the pass-through point, resulting in successful defibrillation.

CONCLUSION

The electroporation-mediated anodal-break excitation mechanism may play an important role in electrical defibrillation.

Cold lability of lactate dehydrogenase isoenzymes and the effective preparation of reference material for clinical laboratory use

To evaluate the storage of samples and enzyme reference materials, and to improve the commutability for inter-laboratory surveillance of activity values of lactate dehydrogenase (LD; EC 1.1.1.27) in clinical laboratory medicine and in animal veterinary medicine, we studied the electrophoretic patterns and cold lability of LD isoenzymes from tissue sources of some common vertebrate species and also from human serum sources. Among many isoenzymes from these sources, only rat LD fractions showed similar electrophoretic patterns to those of human sera, and rat LD-1 fraction was relatively cold-stable. Total LD and isoenzyme LD-1 activities in routine laboratory samples and quality-control sera were measured using eight kinds of commercially available LD assay kit, including lactate and pyruvate substrate systems. Coefficients of variation between these assay kits were markedly reduced when the activities were calculated using the partially purified rat LD-1 fraction as an enzyme reference material, compared with the activities calculated using the factor indicated in each assay kit. In the regression analysis, the intercept and slope were calculated for the regression equations obtained from 12 pairs of these assay kits. The values obtained from a small amount of human serum and control serum samples were within the 95% confidence regions of those from larger amounts of human serum samples by using the present rat LD-1 standard for measuring LD-1 activities with lactate substrate. It was evident that a cold-stable and homogeneous LD isoenzyme as an enzyme reference material might contribute to accurate measurement of activities in heterogeneous samples for inter-laboratory quality-assurance surveys in both human and animal clinical laboratory use.

Immunohistochemical localization of phosphorylated glial fibrillary acidic protein in the prefrontal cortex and hippocampus from patients with schizophrenia, bipolar disorder, and depression

Increasingly, abnormalities of glial cell function have been implicated in pathological studies of the major mental illnesses (schizophrenia, bipolar disorder, and major depression). In a recent proteomic study, four isoforms of astrocytic glial fibrillary acidic protein (GFAP) were decreased in one or more of these diseases. In the current study, we sought to determine the immunohistochemical localization of phosphorylated GFAP (pGFAP) in the prefrontal cortex and hippocampus and to describe possible disease-related changes in the distribution of pGFAP containing astrocytes. In the prefrontal cortex, interlaminar astrocytes in layer I and stellate astrocytes in layers II and VI were labeled. Labeled cells were also present adjacent to blood vessels in the gyral white matter and in underlying white matter generally. In the hippocampus, labeled cells were present in the polymorphic layer of the dentate gyrus. In the prefrontal cortex, schizophrenia and major depression were characterized by decreased labeling of astrocytes adjacent to blood vessels. There were no significant differences between the diagnostic groups in the other prefrontal layers or in the hippocampus. These results suggest that reduced numbers or functional regulation of pGFAP containing astrocytes occurs in schizophrenia and major depression. The mechanism by which this deficit occurs is not known, but it may adversely effect the regulation of neuronal metabolism, communication, and response to injury.

Heart rate-independent vagal effect on end-systolic elastance of the canine left ventricle under various levels of sympathetic tone

BACKGROUND

Although we have shown that in rabbits the direct (heart rate [HR]-independent) vagal effect on left ventricular end-systolic elastance (E(es)) was negligible under minimal sympathetic tone, how underlying sympathetic tone modulates the inotropic response to vagal stimulation remains unknown.

METHODS AND RESULTS

We used an isolated canine heart preparation with functioning autonomic nerves. We examined the direct vagal inotropic effect by measuring E(es) under fixed-rate atrial pacing with or without concomitant sympathetic nerve stimulation. Right and left vagal stimulation at 20 Hz decreased HR by 27+/-3% and 14+/-2%, respectively, and decreased E(es) by 11+/-2% and 6+/-2%, respectively. When we fixed HR by atrial pacing, right and left vagal stimulation at 20 Hz did not decrease E(es) (0.01+/-0.3% and 0.3+/-0.4%; NS). Concomitant left sympathetic nerve stimulation at 4 Hz enhanced direct vagal negative inotropism to -19+/-3% and -34+/-5% for 20-Hz right and left vagal stimulation (interaction, P<0.01).

CONCLUSIONS

Direct vagal negative inotropism was unobservable with minimal sympathetic tone in dogs but was enhanced with concomitant sympathetic stimulation.

Differential regulation of aquaporin expression in astrocytes by protein kinase C

Aquaporins (AQPs) are a family of water-selective transporting proteins with homology to the major intrinsic protein (MIP) of lens, that increase plasma membrane water permeability in secretory and absorptive cells. In astrocytes of the central nervous system (CNS), using the reverse transcription-polymerase chain reaction (RT-PCR), we previously detected AQP3, 5 and 8 mRNAs in addition to the reported AQP4 and 9. However the mechanisms regulating the expression of these AQPs are not known. In this study, we investigated the effects of a protein kinase C (PKC) activator on the expression of AQP4, 5 and 9 in cultured rat astrocytes. Treatment of the cells with TPA caused decreases in AQP4 and 9 mRNAs and proteins in time- and concentration-dependent manners. The TPA-induced decreases in AQP4 and 9 mRNAs were inhibited by PKC inhibitors. Moreover, prolonged treatment of the cells with TPA eliminated the subsequent decreases in AQP4 and 9 mRNAs caused by TPA. Pretreatment of cells with an inhibitor of protein synthesis, cycloheximide, did not inhibit the decreases in AQP4 and 9 mRNAs induced by TPA. These results suggest that signal transduction via PKC may play important roles in regulating the expression of AQP4 and 9.

Keratin attenuates tumor necrosis factor-induced cytotoxicity through association with TRADD

Keratin 8 and 18 (K8/18) are the major components of intermediate filament (IF) proteins of simple or single-layered epithelia. Recent data show that normal and malignant epithelial cells deficient in K8/18 are nearly 100 times more sensitive to tumor necrosis factor (TNF)-induced cell death. We have now identified human TNF receptor type 1 (TNFR1)-associated death domain protein (TRADD) to be the K18-interacting protein. Among IF proteins tested in two-hybrid systems, TRADD specifically bound K18 and K14, type I (acidic) keratins. The COOH-terminal region of TRADD interacted with the coil Ia of the rod domain of K18. Endogenous TRADD coimmunoprecipitated with K18, and colocalized with K8/18 filaments in human mammary epithelial cells. Overexpression of the NH2 terminus (amino acids 1-270) of K18 containing the TRADD-binding domain as well as overexpression of K8/18 in SW13 cells, which are devoid of keratins, rendered the cells more resistant to killing by TNF. We also showed that overexpressed NH2 termini of K18 and K8/18 were associated with endogenous TRADD in SW13 cells, resulting in the inhibition of caspase-8 activation. These results indicate that K18 may sequester TRADD to attenuate interactions between TRADD and activated TNFR1 and moderate TNF-induced apoptosis in simple epithelial cells.

Ultraviolet B-induced phosphorylation of histone H3 at serine 28 is mediated by MSK1

N-terminal tail phosphorylation of histone H3 plays an important role in gene expression, chromatin remodeling, and chromosome condensation. Phosphorylation of histone H3 at serine 10 was shown to be mediated by RSK2, mitogen- and stress-activated protein kinase-1 (MSK1), and mitogen-activated protein kinases depending on the specific stimulation or stress. Our previous study showed that mitogen-activated protein kinases MAP kinases are involved in ultraviolet B-induced phosphorylation of histone H3 at serine 28 (Zhong, S., Zhong, Z., Jansen, J., Goto, H., Inagaki, M., and Dong, Z., J. Biol. Chem. 276, 12932-12937). However, downstream effectors of MAP kinases remain to be identified. Here, we report that H89, a selective inhibitor of the nucleosomal response, totally inhibits ultraviolet B-induced phosphorylation of histone H3 at serine 28. H89 blocks MSK1 activity but does not inhibit ultraviolet B-induced activation of MAP kinases p70/85(S6K), p90(RSK), Akt, and protein kinase A. Furthermore, MSK1 markedly phosphorylated serine 28 of histone H3 and chromatin in vitro. Transfection experiments showed that an N-terminal mutant MSK1 or a C-terminal mutant MSK1 markedly blocked MSK1 activity. Compared with wild-type MSK1, cells transfected with N-terminal or C-terminal mutant MSK1 strongly blocked ultraviolet B-induced phosphorylation of histone H3 at serine 28 in vivo. These data illustrate that MSK1 mediates ultraviolet B-induced phosphorylation of histone H3 at serine 28.

A decade of site- and phosphorylation state-specific antibodies: recent advances in studies of spatiotemporal protein phosphorylation

From 1990 to 2001, numerous site- and phosphorylation state-specific antibodies have been developed and many are now commercially available. These antibodies have facilitated understanding of the cytoskeletal organization, signal transduction and transcriptional mechanisms as well as clinical diseases. This review is an attempt to cover all these aspects.

Successfully resected hepatoblastoma in a young adult with chronic hepatitis B: report of a case

Hepatoblastoma usually occurs in children, but a few cases have also been reported in adults. We report the unusual case of hepatoblastoma in an 18-year-old adult with chronic hepatitis B. He visited a local hospital with right upper abdominal pain. Abdominal ultrasound showed a large mass in the right lobe of his liver. He was referred to our hospital and admitted for further examination. At admission, liver function tests gave slightly elevated results (aspartate aminotransferase (AST) 103 IU/l, alanine aminotransferase (ALT) 63 IU/l). A test for hepatitis virus revealed that he was a hepatitis B surface antigen (HBsAg) carrier and had experienced seroconversion. His alpha-fetoprotein (AFP) was elevated to 1 548 000 IU/ml. Abdominal ultrasound showed a 109 x 96 x 80-mm mass with mosaic pattern in the right lobe of the liver and right portal vein thrombus. Abdominal computed tomography (CT) demonstrated a large low-density mass occupying the right lobe, with some high-density parts that showed calcification. From these results, we diagnosed hepatoblastoma in a young adult. A right lobectomy was performed. Pathological examination showed a highly differentiated hepatoblastoma. Adjuvant chemotherapy was performed with cisplatin and pirarubicin. The patient has been well and free of recurrence for 12 months, and his AFP level remains almost normal.

In vivo assessment of acetylcholine-releasing function at cardiac vagal nerve terminals

We examined whether the ACh concentration measured by cardiac microdialysis provided information on left ventricular ACh levels under a variety of vagal stimulatory and modulatory conditions in anesthetized cats. Local administration of KCl (n = 5) and ouabain (n = 7) significantly increased the ACh concentration in the dialysate to 4.3 +/- 0.8 and 7.3 +/- 1.3 nmol/l, respectively, from the baseline value of 0.6 +/- 0.5 nmol/l. Intravenous administration of phenylbiguanide (n = 5) and phenylephrine (n = 6) significantly increased the ACh concentration to 5.4 +/- 0.9 and 6.0 +/- 1.5 nmol/l, respectively, suggesting that the Bezold-Jarisch and arterial baroreceptor reflexes affected myocardial ACh levels. Modulation of vagal nerve terminal function by local administration of tetrodotoxin (n = 6), hemicholinium-3 (n = 6), and vesamicol (n = 5) significantly suppressed the electrical stimulation-induced ACh release from 20.4 +/- 3.9 to 0.6 +/- 0.1, 7.2 +/- 1.9, and 2.7 +/- 0.6 nmol/l, respectively. Increasing the heart rate from 120 to 200 beats/min significantly reduced the myocardial ACh levels during electrical vagal stimulation, suggesting a heart rate-dependent washout of ACh. We conclude that ACh concentration measured by cardiac microdialysis provides information regarding ACh release and disposition under a variety of pathophysiological conditions in vivo.

Constituents of crinoidea. 2. Isolation and structure of the novel type gangliosides from the feather star Comanthus japonica

Two novel type gangliosides CJP2 and CJP3 have been obtained from the feather star Comanthus japonica. On the basis of methylation linkage analysis combined with ammonolysis and other chemical and spectroscopic evidence, the chemical structures of CJP2 and CJP3 were determined to be alpha-9-O-Me-NeuGc-(2-->3)-inositolphosphoceramide and alpha-9-O-Me-NeuGc-(2-->11)-alpha-9-O-Me-NeuGc-(2-->3)-inositolphosphoceramide, respectively. These gangliosides are unique in that they are inositolphosphoceramide derivatives possessing sialic acid; such gangliosides have not previously been identified. The presence of 9-O-methyl-N-glycolyl-neuraminosyl residues is also unique in naturally occurring gangliosides.

Laterality in direct and indirect inotropic effects of sympathetic stimulation in isolated canine heart

Although sympathetic nerve stimulation is known to increase ventricular contractility, concomitant increases in heart rate (HR) make it difficult to separate its direct inotropic effect from indirect inotropic effect through a force-frequency mechanism. We stimulated the stellate ganglia in 8 isolated canine hearts with functional sympathetic nerves. Right sympathetic stimulation at 10 Hz increased ventricular end-systolic elastance (E(es)) by 95.7 +/- 7.5% (p < 0.001) and HR by 32.5 +/- 4.2% (p < 0.05). In contrast, left sympathetic stimulation at 10 Hz increased E(es) by 70.7 +/- 6.5% (p < 0.001) without significant changes in HR. Preventing the chronotropic response by fixed-rate pacing attenuated the E(es) response to right sympathetic stimulation at 5 Hz (52.0 +/- 5.1 vs. 22.8 +/- 2.8%, p < 0.001), but not to left sympathetic stimulation at 5 Hz (54.5 +/- 3.4 vs. 53.3 +/- 2.2%, NS). In the isolated canine heart, the right sympathetic nerve affected E(es) by both the direct inotropic effect and the indirect HR-dependent inotropic effect. In contrast, the left sympathetic nerve regulated E(es) primarily by its direct inotropic effect.

[Psycho-oncology and its scientific background]

Psycho-oncology has two purposes corresponding to the psychosocial aspects of cancer: 1. to clarify the psychosocial impacts of cancer on the quality of life of the patient, family and staff; 2. to clarify the role that psychosocial and behavioral variables may have in cancer risk and survival. For these purposes, patient education, counseling, behavioral and psychopharmacological techniques have been applied to clinical oncology. In this paper, we review psycho-oncology and its scientific background, with respect to neuroradiology and molecular genetics, as well as psychiatry, psychology, epidemiology, pharmacology and immunology.

Protein kinases required for segregation of vimentin filaments in mitotic process

Vimentin, one of type III intermediate filament (IF) proteins, is expressed not only in mesenchymal cells but also in most types of tumor cells. In the present study, we introduced several types of vimentin mutated at putative phosphorylation sites in its amino-terminal head domain into type III IF-negative T24 cells. Site-specific mutation induced the formation of an unusually long bridge-like IF structure between the unseparated daughter cells, although these mutants formed the filament network similar to wild type in interphase cells. Together with sites phosphorylated by Rho-kinase and protein kinase C (PKC), vimentin-Ser72, which can not be phosphorylated by any known vimentin kinase, was one of the mutation sites essential for this phenotype. We further demonstrated that vimentin-Ser72 was phosphorylated specifically at the cleavage furrow during cytokinesis. These observations suggest the existence of a novel protein kinase responsible for vimentin filament separation through the cleavage furrow-specific vimentin phosphorylation. We propose that Rho-kinase, PKC, and an unidentified vimentin-Ser72 kinase may play important roles in vimentin filament separation during cytokinesis.

Immunomodulation based on a two-way paradigm with deoxyspergualin alleviates graft-versus-host reaction in small-bowel transplantation in rats

In this study, we investigated whether or not deoxyspergualin used as donor pretreatment, with and without pretreatment using bone-marrow-cell injection, could alleviate graft-versus-host reaction (GVHR) following small-bowel transplantation in an unidirectional GVHR model with Lewis (LEW)-to-F1 rats. In addition, we studied the effect of deoxyspergualin plus bone-marrow-cell donor pre-operative treatment in combination with recipient postoperative treatment using deoxyspergualin. When the donor was pretreated with bone-marrow cells from recipient rats, the recipient died at 7.2+/-1.4 days, showing significantly shorter survival compared with the control group. Deoxyspergualin, when employed either alone as recipient post-treatment or as donor pretreatment, both with and without additional pretreatment with F1 recipient bone-marrow-cell injection, did not result in significant prolongation of recipient survival. The combination of donor pretreatment with deoxyspergualin plus F1 bone-marrow-cell injection followed by post-operative deoxyspergualin administration, however, resulted in significant prolongation in recipient survival compared with control (26.1+/-1.7 days). In addition, no severe cutaneous lesions on GVHR were seen throughout the observation period. This suggests that donor pretreatment with deoxyspergualin and recipient bone-marrow-cell injection combined with postoperative deoxyspergualin administration can lead to resistance to GVHR after parent-to-F1 small-bowel transplantation.

Graft-versus-host reaction in small-bowel transplantation and possibilities for its circumvention

To study graft-versus-host reaction (GVHR) in small-bowel transplantation and its underlying mechanisms and to find methods for circumventing GVHR, we used an unidirectional GVHR model in which F1 Lewis (LEW) x Wistar King A (WKA) hybrid rats received small-bowel transplants from either LEW or WKA parent rats. The survival time of F1 hybrid rats that received full-length small-bowel transplantation from LEW and WKA was 16.3+/-2.1 days and 18.2+/-3.4 days, respectively. When one-quarter of LEW small bowel was transplanted to an F1 hybrid recipient, the survival time was significantly longer at 44.0+/-23.4 days compared with rats that had received full-length LEW small-bowel transplantation. The survival time of F1 hybrid rats which received an injection of high-dose (5 x 10(8) cells) LEW or WKA spleen cells was 11.9+/-4.0 days and 13.1+/-3.6 days, respectively. However, when an injection containing a low dose (1 x 108 cells) of LEW spleen cells was used, survival was > 100 days, showing significance compared with the survival of rats receiving the higher dose LEW spleen-cell injection. Both small-bowel transplantation and spleen-cell injection were compared for the effective period of recipient resistance to donor cell or small-bowel transplantation as second challenge. When the F1 rats given a quarter LEW small-bowel transplant as first challenge were treated with a high-dose of spleen cells 30 days after transplantation, they survived for > 30 days without GVHR. F1 rats that were treated with a low-dose LEW spleen-cell injection, followed 30 days later by full LEW small-bowel transplantation, had a survival time of > 100 days. These results indicate that segmental small-bowel transplantation and spleen-cell injection as first challenge may facilitate the prevention of GVHR, resulting in resistance to subsequent immunological challenge.

MAP kinases mediate UVB-induced phosphorylation of histone H3 at serine 28

Histone H3 phosphorylation is related closely to chromatin remodeling and chromosome condensation. H3 phosphorylation at serine 28 is coupled with mitotic chromosome condensation in diverse mammalian cell lines. However, the pathway that mediates phosphorylation of H3 at serine 28 is unknown. In the present study, ERK1, ERK2, or p38 kinase strongly phosphorylated H3 at serine 28 in vitro. JNK1 or JNK2 was able also to phosphorylate H3 at serine 28 in vitro but to a lesser degree. UVB irradiation markedly induced phosphorylation of H3 at serine 28 in JB6 Cl 41 cells. PD 98059, a MEK1 inhibitor, and SB 202190, a p38 kinase inhibitor, efficiently repressed UVB-induced H3 phosphorylation at serine 28. Expression of dominant negative mutant (DNM) ERK2 in JB6 Cl 41 cells totally blocked UVB-induced phosphorylation of H3 at serine 28. Additionally, DNM p38 kinase or DNM JNK1 partially blocked UVB-induced H3 phosphorylation at serine 28. Furthermore, UVB-induced H3 phosphorylation at serine 28 was inhibited in Jnk1(-/-) cells but not in Jnk2(-/-) cells. These results suggest that UVB-induced H3 phosphorylation at serine 28 may be mediated by mitogen-activated protein kinases.