We examined the structure of protein kinase C in an attempt to understand the molecular events connecting protein kinase C activation with the cellular response. Rabbit complementary DNA clones coding for three distinct types of protein kinase C, named alpha, beta and gamma, have been identified and sequenced. The deduced amino acid sequence for alpha, beta and gamma (673, 671 and 672 amino acids, respectively) are closely related. Kinases alpha and beta share an identical N-terminal sequence of 621 amino acid residues and their messenger RNAs arise from a single gene. The C-terminal halves of alpha, beta and gamma are protein kinase domains and are highly homologous to other protein kinases. The mRNAs for alpha, beta and gamma are expressed in various tissues with strikingly different tissue specificities. The one for gamma is found ubiquitously among various tissues, while those for alpha and beta predominate in the brain.

Amino Acid Sequence↗

PubMedDate not supplied

Site-specific phosphorylation induces disassembly of vimentin filaments in vitro.

Intermediate filaments are a major component of the cytoskeleton of eukaryotic cells. Although there appear to be at least five distinct classes of these filaments, cells of mesenchymal origin and most cells in culture contain the intermediate filament composed of the subunit protein vimentin. Vimentin exists in a nonphosphorylated as well as in a phosphorylated form, and there is increased phosphorylation of this protein when the filament undergoes marked redistribution in various cells. The role of phosphorylation on assembly-disassembly and organization of the vimentin filament has remained obscure. We report here a stable and purified system allowing biochemical examination of vimentin filament assembly and disassembly. Using this in vitro system, we carried out stoichiometrical phosphorylations, using purified protein kinases. We obtained evidence for site-specific, phosphorylation-dependent disassembly of the vimentin filament.

Animals↗

PubMedDate not supplied

Infection with hepatitis delta and human immunodeficiency viruses among hemophiliacs in Japan.

Two hundred two patients with hemophilia, dependent solely on imported coagulation factor concentrates, were tested for markers of hepatitis B virus infection, antibody to hepatitis delta virus (anti-HD), and antibody to human immunodeficiency virus (anti-HIV). Nine carriers of hepatitis B surface antigen (HBsAg) were identified. Six (66.7%) of them were positive for anti-HD, a prevalence much higher than that in HBsAg carriers without hemophilia in Japan (1/113 or 0.9%, p less than 0.001). Anti-HIV was found in 96 (47.5%), in sharp contrast to the low prevalence (0/1205) in apparently healthy blood donors (p less than 0.001). These results implicated imported plasma products in the transmission of both delta and human immunodeficiency viruses to hemophiliacs. An efficient method for the sterilization of plasma products is warranted to prevent exposure of hemophiliacs to the accompanying pathogenic viruses.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Angiotensin-converting enzyme inhibitor therapy affects myocardial fatty acid metabolism after acute myocardial infarction.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitor therapy has an early mortality benefit in unselected patients with acute myocardial infarction (AMI). However, the effects of ACE inhibition on myocardial fatty acid metabolism in this patient population have not been studied. We tested the hypothesis that ACE inhibitor therapy improves myocardial fatty acid metabolism and decreases mortality rate in patients after AMI. METHODS: Forty-two patients after first anterior AMI and primary angioplasty were randomly assigned to titrated oral enalapril (n = 24) or placebo therapy (n = 18). Iodine 123-labeled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) single photon emission computed tomography imaging was performed an average of 4.8 days after AMI and 1 month after AMI. BMIPP abnormalities were quantified as a severity index by a polar map. RESULTS: There were no significant changes in baseline characteristics, cardiac function, and angiographic findings between patients in the enalapril group and patients in the placebo group. However, BMIPP severity index from acute phase to chronic phase was significantly decreased in the enalapril-treated group (118+/-48 to 82+/-36, P<.05), but not in the placebo group (123+/-65 to 115+/-58, P not significant). CONCLUSION: ACE inhibition therapy improved myocardial fatty acid metabolism and regional left ventricular function in patients after anterior AMI. BMIPP single photon emission computed tomography findings imply that this better outcome may be attributable to an improvement of cellular function with ACE inhibitors.

Adult↗

PubMedDate not supplied

Nicorandil affords cardioprotection in patients with acute myocardial infarction treated with primary percutaneous transluminal coronary angioplasty: assessment with thallium-201/iodine-123 BMIPP dual SPECT.

BACKGROUND: It has been reported that nicorandil restores blood flow to reperfused myocardium in patients with acute myocardial infarction. However, whether nicorandil might decrease infarct size remains unclear. The aim of this study was to assess the effect of nicorandil on infarct size with thallium-201/beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP) dual-isotope single photon emission computed tomography. METHODS: A total of 62 patients were randomly assigned to receive intravenous nicorandil (4 mg in 5 minutes at admission, immediately followed by 6 mg/hr over a 24-hour period) or placebo. All patients were divided into 4 groups: Group N-a, 16 patients with preexisting angina treated with nicorandil; N-b, 15 patients without preexisting angina treated with nicorandil; C-a, 14 patients with preexisting angina given placebo; C-b, 17 patients without preexisting angina given placebo. Tl-201/BMIPP imaging was performed in the 62 patients within 7 days after admission. Dual-isotope single photon emission computed tomographic images were quantified by severity index with a polar map. RESULTS: The BMIPP severity index was similar among the 4 groups. Only the thallium severity index in the N-a group was significantly less (P<.05). The ratio of the thallium severity index to that of BMIPP in the N-a group was significantly decreased compared with those of the other groups. CONCLUSION: Nicorandil has a protective effect in patients with acute myocardial infarction and preexisting angina treated with primary balloon angioplasty.

Angina, Unstable↗

PubMedDate not supplied

A case of alpha-fetoprotein-producing adenocarcinoma of the endometrium with a hepatoid component as a potential source for alpha-fetoprotein in a postmenopausal woman.

Although case reports of alpha-fetoprotein (AFP)-producing adenocarcinoma other than hepatocellular carcinoma have gradually increased in number, AFP-producing adenocarcinoma of the endometrium is very rare. The patients universally complain of abnormal vaginal bleeding. The patient presented with complaints of epigastric discomfort. No vaginal bleeding was observed. Serum AFP concentration was 453 ng/mL, and lens culinaris agglutinin-reactive AFP percentage of total AFP was increased to 67%. Radiologic imaging and endoscopy did not provide evidence of any primary carcinoma in the liver and gastrointestinal tract. To investigate the unknown origin of high AFP, Pap smear of the endometrium followed by fractional curettage was performed and revealed adenocarcinoma of the endometrium. Radical hysterectomy with pelvic lymph node dissection and partial omentectomy was performed. Histologic study showed a mixture of major AFP-negative endometrioid adenocarcinoma and minor medullary proliferation of the AFP-positive hepatoid adenocarcinoma cells with eosinophilic cytoplasm and hyaline globules. After the surgery followed by four courses of weekly carboplatin and paclitaxel administration, serum levels of AFP dropped into normal range. The possible existence of AFP-producing adenocarcinoma of the endometrium should be considered in a postmenopausal woman even if there is no vaginal bleeding, when AFP-producing tumor is clinically suspected and the imaging studies fail to confirm the diagnosis.

Carcinoma, Endometrioid↗

PubMedDate not supplied

Ultrastructure of mucous blanket in otitis media with effusion.

We used transmission electron microscopy to study the mucous blanket of the promontory from children with otitis media with effusion. The vast majority of the epithelial cells were secretory, and the rest were ciliated. The mucous blanket consisted of the electron-lucent periciliary fluid and the mucous layer. In the mucous layer, two layers were identified: an inner layer with migrating cells, and an outer layer with specks. Moreover, there was a lucent zone over the nonciliated surface that was as high as the microvilli. The thickness of the periciliary layer was predominantly as great as that of the ciliary tips, which just make contact with the mucous layer; however, the mucous layer occasionally penetrated into the periciliary space. These findings indicated that there is a mucociliary dysfunction in the middle ear caused by a decrease in the number of ciliated cells, and an abnormal interaction between cilia and mucus that would interfere with ciliary movement. Thus, such a system would fail to transport the mucous blanket.

Biopsy↗

PubMedDate not supplied

Donor dendritic cells and recipient Kupffer cells in the induction of donor-specific immune hyporesponsiveness.

The aim of this study was to investigate the ability of portovenously administered donor antigens to induce immune hyporesponsiveness. Lewis (LEW, RT-1l) rats received Brown Norway (BN, RT-1n) rat donor splenocytes, via either the portal vein (PV group) or the peripheral vein (IV group). The immune responses of LEW rats, treated with either donor BN or third party Wistar King A (WKA, RT-1k) splenocytes were established by the persistence of donor dendritic cells (DCs) in the host liver measured using fluorescence microscopy and flow cytometry and by the mixed lymphocyte reaction (MLR). The effect of intravenous gadolinium chloride (GDCl3) on the blockade of Kupffer cell function prior to portovenous administration of splenocytes was also assessed. The MLR response was strongly inhibited in a BN-restricted manner after portovenous administration of donor BN splenocytes, but not by venous nor by portovenous administration of WKA splenocytes. Immunosuppression was blocked by pretreatment with GDCl3. The percentage of donor DCs in hepatic non-parenchymal cells (NPCs) was significantly higher in the PV group compared with the IV group. Treatment with GDCl3 decreased the percentage of donor DCs. In addition, cytotoxic T lymphocyte antigen 4 (CTLA4/CD152), which may function as an immune attenuator, was strongly stained, and B7 was weakly stained in recipient liver in the PV group compared with the IV group. These results suggest that both donor DCs and recipient Kupffer cells (self DCs) are involved in the induction of immune hyporesponsiveness by donor cells. This occurs via portovenous administration, in which a signal of the CTLA4-B7 pathway played an important part in inhibiting the interaction of CD28 and its B7 ligands.

Abatacept↗

PubMedDate not supplied

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.

Animals↗

PubMedDate not supplied

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.

Animals↗

PubMedDate not supplied

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.

Adult↗

PubMedDate not supplied

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.

Aged↗

PubMedDate not supplied

Activated T cells and soluble molecules in the portal venous blood of patients with cholestatic and hepatitis C virus-positive liver cirrhosis. Possible promotion of Fas/FasL-mediated apoptosis in the bile-duct cells and hepatocyte injury.

We investigated the immune responses of patients with cholestatic and hepatitis C virus-positive (HCV-positive) liver cirrhosis by analysing T-cell subsets and cytokine levels in the portal and peripheral veins, using flow cytometry and enzyme-linked immunosorbent assay. In cholestatic liver cirrhosis, the proportion of natural-killer (NK) T cells and interleukin (IL) 6 and IL-18 levels in the portal venous blood were significantly higher than those in the peripheral venous blood. In HCV-positive liver cirrhosis, the proportions of NK T cells and Fas+ T cells and IL-6 and soluble Fas levels in the portal venous blood were significantly higher than those in the peripheral venous blood. These results suggest that in these diseases, activated T cells and soluble molecules in portal venous blood may promote Fas/FasL-mediated apoptosis of the bile-duct cells and hepatocytes, and contribute to the deterioration in liver function as an inevitable result of positive feedback.

Adult↗

PubMedDate not supplied

Intraportal donor bone marrow transplantation improves intestinal allograft survival in rats under FK506-based immunosuppression.

Donor-specific immunosuppression is important in transplant surgery. We examined the effect of intraportal donor-specific bone marrow transplantation on heterotopic small bowel transplantation in the high responder rat combination, ACI to Lewis. The study comprised five treatment groups: untreated controls (group 1); FK506 alone (group 2); low-dose predonine + FK506 (group 3); high-dose predonine + FK506 (group 4); and intraportal donor-specific bone marrow transplantation + FK506 (group 5). Intraportal transplantation was performed pre-operatively and FK506 and predonine given post-operatively. Intestinal allograft survival and changes of intragraft cytokine expression were analysed using the reverse transcription polymerase chain reaction. Allograft survival (mean +/- SD) was lowest in group 1 and greatest in group 5. The group 5 treatment regimen also down-regulated interferon-gamma and interleukin-2 transcription in the transplanted intestine. Intraportal donor bone marrow transplant combined with FK506 immunosuppression was found therefore to be the most beneficial treatment regimen.

Animals↗