The c-IAP-1 and c-IAP-2 proteins are direct inhibitors of specific caspases

The inhibitor of apoptosis (IAP) family of proteins are highly conserved through evolution. However, the mechanisms by which these proteins interfere with apoptotic cell death have been enigmatic. Recently, we showed that one of the human IAP family proteins, XIAP, can bind to and potently inhibit specific cell death proteases (caspases) that function in the distal portions of the proteolytic cascades involved in apoptosis. In this study, we investigated three of the other known members of the human IAP family, c-IAP-1, c-IAP-2 and NAIP. Similarly to XIAP, in vitro binding experiments indicated that c-IAP-1 and c-IAP-2 bound specifically to the terminal effector cell death proteases, caspases-3 and -7, but not to the proximal protease caspase-8, caspases-1 or -6. In contrast, NAIP failed to bind tightly to any of these proteases. Recombinant c-IAP-1 and c-IAP-2 also inhibited the activity of caspases-3 and -7 in vitro, with estimated Kis of <=0.1 microM, whereas NAIP did not. The BIR domain-containing region of c-IAP-1 and c-IAP-2 was sufficient for inhibition of these caspases, though proteins that retained the RING domain were somewhat more potent. Utilizing a cell-free system in which caspases were activated in cytosolic extracts by addition of cytochrome c, c-IAP-1 and c-IAP-2 inhibited both the generation of caspase activities and proteolytic processing of pro-caspase-3. Similar results were obtained in intact cells when c-IAP-1 and c-IAP-2 were overexpressed by gene transfection, and apoptosis was induced by the anticancer drug, etoposide. Cleavage of c-IAP-1 or c-IAP-2 was not observed when interacting with the caspases, implying a different mechanism from the baculovirus p35 protein, the broad spectrum suicide inactivator of caspases. Taken together, these findings suggest that c-IAP-1 and c-IAP-2 function similarly to XIAP by inhibiting the distal cell death proteases, caspases-3 and -7, whereas NAIP presumably inhibits apoptosis via other targets.

CAG repeat length and disease duration in Machado-Joseph disease: a new clinical classification

To evaluate the clinical characteristics of Machado-Joseph disease (MJD) with reference to CAG repeat length and disease duration, we analyzed neurologic findings in 108 patients from 84 families. The majority of MJD patients presented with an ataxic gait as the initial symptom. Dysarthria and nystagmus were observed from an early stage. Bulging eyes, muscle atrophy and bradykinesia developed later. Patients with a shorter CAG repeat length or later onset had more frequent involvement of proprioceptive sensory deficit. Incidence of abnormal reflexes, tones, and proprioceptive sensation was not associated with disease duration, but with CAG repeat length. Based on these results, we propose a new clinical classification: type A (juvenile type), with hyperreflexia and dystonia, but without a proprioceptive sensory deficit; type C (adult type), with hyporeflexia and a proprioceptive sensory deficit, but without dystonia; and type B (intermediate type), the remaining patients with a mixed presentation.

Biodegradabilities of ethylenediamine-N,N'-disuccinic acid (EDDS) and other chelating agents

Biodegradabilities of chelating agents were tested with activated sludge. Ethylenediaminetetraacetic acid (EDTA) remained intact in the effluent even after acclimation for 100 days, but propanediamine-N,N'-disuccinic acid (PDDS) and nitrilotriacetic acid (NTA) were biodegraded after acclimation for 5 and 23 days, respectively. Optical isomers of ethylenediamine-N,N'-disuccinic acid (EDDS) had different biodegradabilities: SS- and RS-isomers were susceptible to biodegradation, but the RR-isomer was resistant. SS-isomer was degraded even by activated sludge without acclimation.

The protective effects of prostaglandin E1 on sinusoidal endothelial cells in xenogeneic pig liver perfusion

The effects of prostaglandin E1 (PGE1) on hepatic sinusoidal endothelial cells (SEC) in the xenogeneic immunoreaction were investigated. Porcine livers were perfused with fresh human blood via the portal vein (PV) and the hepatic artery (HA) either with the administration of PGE1 (Group PG) or without PGE1 (Group C). The creatine kinase-BB component (CK-BB) in the perfusate was measured to assess SEC damage. SEC activation and complement activation were evaluated immunohistochemically by the expression of von Willebrand factor (vWF) and by the deposition of membrane attack complex (MAC), respectively. Xenoperfusion in Group C was discontinued between 4 and 6 hr due to the rapid elevation of HA pressures and the massive loss of perfusate. In Group PG, both PV and HA pressures were kept stable for up to 9 hr. In Group C, severe interlobular bleeding and diffuse extrasinusoidal hemorrhage were observed at 4 hr histologically, while in Group PG, the hepatic architecture was maintained without hemorrhage at 6 hr. MAC was markedly deposited on SEC and parenchymal cells at 3 hr in both groups. The amount of vWF, however, was expressed on SEC in large amounts at 1 hr in Group C, while small amounts were expressed at 1 hr in Group PG. In Group PG, CK-BB release was significantly lower than in Group C (P < 0.01). These results suggest that PGE1 suppressed SEC activation and protected the impairment of hepatic SEC during xenoperfusion without suppressing complement activation, resulting in the prolongation of xenogeneic liver perfusion.

Humoral injury in porcine livers perfused with human whole blood

BACKGROUND

We investigated the influence of humoral injury during xenoperfusion of porcine livers by human blood.

METHODS

The porcine livers were perfused under physiological conditions for 9 hr. The perfusates consisted of porcine whole blood in group 1, human whole blood in group 2, and human whole blood with soluble complement receptor type 1 (300 microg/ml) in group 3.

RESULTS

Liver enzyme release and serum hemoglobin in group 2 increased significantly after 3 hr of xenoperfusion, compared with those in group 1 and group 3 (P<0.05). Severe histological damage with minimal cellular infiltration was observed in group 2 after 6 hr of xenoperfusion, but was present only at trace levels in group 1 and group 3. In group 2, von Willebrand factor, a possible target of natural antibodies, was induced on sinusoidal endothelial cells after 3 hr of xenoperfusion, correlating with diffuse deposition of human IgM and membrane attack complex. In group 3, von Willebrand factor, human IgM, and membrane attack complex staining in the intralobular region were present at trace levels. In group 3, the indocyanine green removal capacity, representing hepatocyte function, was significantly higher than in group 2 (P<0.05).

CONCLUSIONS

Based on these results, we suggest that humoral injury is a major cause of liver damage during liver xenoperfusion. The pattern of humoral injury in xenoperfused livers may be attributed to anatomical features of the liver and unique responses of sinusoidal endothelial cells to xenoperfusion.

Flow cytometric analysis of Thy-1 expression in CD34-positive acute leukemia

We analyzed the expression of the Thy-1 antigen (CD90) in CD34+ acute leukemia using two-color flow cytometry. Leukemic cells were obtained from the bone marrow (BM) and/or the peripheral blood (PB) of 57 patients: 37 with acute myelogenous leukemia (AML) including nine with secondary AML following myelodysplastic syndrome (MDS/AML), and 20 with acute lymphoblastic leukemia (ALL) including three with chronic myelogenous leukemia in blast crisis (CML-BC) of the lymphoid type. Among these patients, one (3.6%) with de novo AML, two (22.2%) with MDS/AML, three (17.6%) with de novo ALL, and two (66.7%) with CML-BC coexpressed CD34 and Thy-1 (CD34+ Thy-1+) on more than 20% of the mononuclear cells within 'lymph' plus 'blast' window. Thy-1 was rarely expressed in de novo acute leukemia especially in AML. Interestingly, in 1 patient with CML-BC, the leukemic cells in BM were divided into two subpopulations (CD34+ Thy-1low and CD34+ Thy-1high), whereas most of the CD34+ leukemic cells in PB were Thy-1high. However, the mechanism for the mobilization of CD34+ Thy-1high leukemic cells into the PB is unknown.

Hypermethylation in the retinoblastoma gene is associated with unilateral, sporadic retinoblastoma

We previously reported 9 unilateral, sporadic retinoblastomas with hypermethylation in the 5' region of the RB gene, and we found that CpG methylation in the RB promoter inhibits the binding of the retinoblastoma binding factor 1 (RBF-1) and the activating transcription factor (ATF)-like factors, thereby resulting in a considerable reduction in RB promoter activity. In this study, we screened for hypermethylation in 121 additional cases of retinoblastoma, and found 5 tumors with hypermethylation, including 4 unilateral, sporadic tumors, and one hereditary tumor. The hereditary tumor had a germline deletion of one allele, and the hypermethylation was an acquired, epigenetic change in the other allele. Another tumor had hypermethylation restricted to approximately 800 base pairs in the RB promoter region including the essential RBF-1 and ATF sites. The frequency of hypermethylation in unilateral, sporadic tumors was 9.3% combining our previous and present examinations (13 among 140), whereas the frequency was 1.0% in bilateral hereditary tumors (one among 101). The statistical analyses using the chi-square test indicated significant correlation between hypermethylation and unilateral, sporadic tumors (p < 0.05). These results suggest that hypermethylation in the RB gene is always an acquired, epigenetic change and causes about 9% of unilateral, sporadic tumors.

Abnormal calcium metabolism in myotonic dystrophy as shown by the Ellsworth-Howard test and its relation to CTG triplet repeat length

Myotonic dystrophy (DM) is an autosomal dominant disorder characterized by peculiar clinical features. Its molecular basis is the unstable expansion of a CTG triplet repeat in the gene encoding myotonin protein kinase (Mt-PK), the nucleotide sequence of which has extensive homology to the cyclic AMP (cAMP)-dependent protein kinase gene. Extensive efforts have been made to clarify the signal transduction pathway in which the responsible gene operates, but confirming evidence has yet to be obtained. Because some symptoms in DM are similar to those in hypoparathyroidism, we divided 24 DM patients into two groups on the basis of their serum calcium levels; Group 1, those with normocalcemia (11 patients), and group 2, those with hypocalcemia (13 patients). The highly sensitive parathyroid hormone (HS-PTH) plasma levels in group 1 were within normal limits, whereas those in group 2 were abnormally high. Laboratory findings for the group 2 patients resembled those for pseudohypoparathyroidism (PHP), whereas those for group 1 patients were normal. The Ellsworth-Howard (EH) test was used to determine which type of PHP the group 2 patients belonged to. Both the phosphaturic (delta P) and urinary cAMP (UcAMP) responses were estimated. The delta P responses in group 2 were significantly lower than those in group 1, but their UcAMP responses did not differ. This is evidence that group 2 patients had PHP type II, whereas group 1 patients were normal. We also investigated whether the disease severity differed between the groups. Cataracts, ectopic calcifications, and ossifications, which are associated with PHP, were more frequent in group 2. In addition, the mean IQ in that group was significantly lower. Clinically, the group 2 signs agreed well with those of PHP, whereas for group 1 there was only a slight similarity. These results are additional evidence that the patients in group 2 have abnormal calcium metabolism, the abnormality being in the postadenylate cyclase-cAMP pathway in the renal tubular cells. The degree of (CTG)n expansion, the so-called expanded DNA fragment (EF) size, was determined by standard Southern blot analysis. The allelic EF sizes in both groups were greater than in the healthy controls. Moreover, those in group 2 were significantly longer than those in group 1. We therefore investigated whether EF size is correlated with the serum calcium and plasma PTH levels, the delta P responses in the EH test, and IQ. All these items were significantly correlated with EF size. Our findings show that the expanded DNA fragment size in DM is correlated with the degree of abnormal calcium metabolism.

[p53]

The gene coding p53 is commonly affected by deletions, rearrangements, or point mutations in a variety of human cancers. p53 is a nuclear phosphoprotein. Mutations are frequently found at highly conserved residues of the p53 protein. The mutant p53 proteins examined so far each have a much longer half-life than that of the wild-type p53 protein which is rapidly degraded under normal conditions. Alterations of p53 protein conformation result in the accumulation of such protein usually in transformed cells or cancer cells. The p53 protein is a sequence-specific DNA-binding protein that is active as a transcription factor. The genes coding p21, GADD45, mdm2, cyclin G etc. contain such a p53 responsive element. Upon exposure of cells to ionizing radiation, ultraviolet light, or DNA-damaging agents, high levels of p53 accumulate, resulting in subsequent stimulation of a series of p53-responsive genes and cell cycle arrest or apoptosis. The function of p53 is also linked to DNA synthesis via interaction with p21 and PCNA. The pathways involving p53 seem to be extremely complicated but may play an important role in the core function of cell growth.

X-linked IAP is a direct inhibitor of cell-death proteases

The inhibitor-of-apoptosis (IAP) family of genes has an evolutionarily conserved role in regulating programmed cell death in animals ranging from insects to humans. Ectopic expression of human IAP proteins can suppress cell death induced by a variety of stimuli, but the mechanism of this inhibition was previously unknown. Here we show that human X-chromosome-linked IAP directly inhibits at least two members of the caspase family of cell-death proteases, caspase-3 and caspase-7. As the caspases are highly conserved throughout the animal kingdom and are the principal effectors of apoptosis, our findings suggest how IAPs might inhibit cell death, providing evidence for a mechanism of action for these mammalian cell-death suppressors.

Overexpression of PRAD1/cyclin D1 in plasma cell leukemia with t(11;14)(q13;q32)

Two patients with plasma cell leukemia (PCL) with a t(11;14)(q13;q32) translocation are reported. Case 1 is a 64-year-old woman diagnosed as having primary PCL (IgA/lambda, Stage III) with high serum LDH and beta 2-microglobulin (beta 2MG) levels. She was treated with combination chemotherapy but died of gastrointestinal bleeding on the 45th hospital day. Case 2 is a 52-year-old man, initially diagnosed with multiple myeloma (IgG/kappa, Stage III) in August 1993. Relapse several months after primary chemotherapy was characterized by a rapid increase in plasma cells in peripheral blood, high serum LDH and beta 2MG levels, and resistance to further chemotherapy. Both cases showed complex karyotypic abnormalities including t(11;14), and Northern analysis revealed overexpression of the PRAD1/ cyclin D1 gene. The PRAD1 gene is found on chromosome band 11q13 and encodes cyclin D1. Cyclin D1 plays an important role in control of the cell cycle, and overexpression of PRAD1/cyclin D1 may be involved in disease progression in these cases.

[Changes in patterns of morbidity over 10 years among elderly patients with stroke who were treated in a rehabilitation unit]

We examined changes in outcomes among elderly patients with stroke who were admitted to the rehabilitation unit of our hospital from April, 1985 to March, 1995. During that period, 933 patients (489 men and 444 women, average age 71.3 years) were admitted and received physical therapy. During those 10 years, the average age of the patients increased, functional status with regard to sitting up and walking worsened, and the incidence of urinary incontinence at the time of discharge increased. In contrast, the percentage of patients discharged to home (50 to approximately 60%), the degree of impairment of lower extremities, and the onset-to-admission interval (3 to 4 months) did not change.

Roles of inhibitors of myosin light chain kinase and tyrosine kinase on cation influx in agonist-stimulated endothelial cells

Agonist-stimulated Ca2+ influx is critically important to mediate the function of endothelial cells. It has been suggested that release of Ca2+ from internal stores activates Ca2+ influx across the plasma membrane. In the present study, we investigated the effects of ML-9, a myosin light-chain kinase (MLCK) inhibitor, and genistein, a tyrosine kinase inhibitor, on the agonist stimulated Ca2+ response in porcine aortic endothelial cells loaded with a Ca2+-sensitive dye, fura-2. ML-9 almost completely abolished Ca2+ influx, whereas genistein only partially attenuated Ca2+ entry. Both of them did not affect the mobilization of Ca2+ from internal stores. In contrast, genistein was more potent in the inhibition of Mn2+ influx than ML-9. These findings indicate the different selectivity for Ca2+ and Mn2+ in the cation entry pathway in agonist-stimulated endothelial cells.

Position-independent and high-level expression of human alpha-lactalbumin in the milk of transgenic rats carrying a 210-kb YAC DNA

The level of expression of transgenes in transgenic animals varies among lines, and is often much lower than that of endogenous genes (position effects). In order to surmount position effects and establish a more efficient production system of transgenic animals producing pharmaceutical proteins in their milk, transgenic rats carrying 210-kb YAC DNA containing the human alpha-lactalbumin gene were produced. Three transgenic lines transmitted the transgene to the next generation. They had one copy of the alpha-lactalbumin gene and secreted human alpha-lactalbumin in their milk at concentrations of 2.0-4.3 mg/ml. No position effect was seen. The transgene was expressed specifically in the mammary gland of the transgenic rats. The 210-kb region is thought to contain all the DNA elements required for proper expression of the human alpha-lactalbumin gene. The YAC carrying the human alpha-lactalbumin gene is a potential vector for the expression of foreign genes in the mammary gland.

Pustulotic arthro-osteitis associated with acetabular cartilage lesion in pustulotic arthropathy--implication of bone marrow

We describe a case of pustulotic arthro-osteitis with hip joint involvement. After right hip joint and walking did not improve despite drugs and physical therapy, total hip replacement was performed. During surgery, brownish degenerated tissue was detected on the surface of the acetabular side. Pathohistological examination revealed that granulation tissue caused by suppurative inflammation of the bone marrow had broken through the cartilage surface, reaching the superficial layer. Our findings suggest that hip joint lesions in pustulotic arthro-osteitis may originate from bone marrow lesions.

Selective production of transgenic mice using green fluorescent protein as a marker

The low efficiency of transgenic animal production by microinjection has been a serious problem especially for the production of transgenic livestock. We developed a method to selectively produce transgenic mice using green fluorescent protein (GFP) as a marker. Using this method, we obtained eight fetuses and four live-born mice derived from 55 GFP-positive blastocysts. PCR analysis showed 11 out of 12 mice (fetuses and newborn mice) were transgenic. Southern blot analysis showed that 8 out of 12 were transgenic. GFP expression was also observed in bovine blastocysts, suggesting that this method should contribute to the efficient production of transgenic livestock.

Transgenic rescue from embryonic lethality and renal carcinogenesis in the Eker rat model by introduction of a wild-type Tsc2 gene

We recently reported that a germ-line insertion in the rat homologue of the human tuberous sclerosis gene (TSC2) gives rise to dominantly inherited cancer in the Eker rat model. In this study, we constructed transgenic Eker rats with introduction of a wild-type Tsc2 gene to ascertain whether suppression of the Eker phenotype is possible. Rescue from embryonic lethality of mutant homozygotes (Eker/Eker) and suppression of N-ethyl-N-nitrosourea-induced renal carcinogenesis in heterozygotes (Eker/+) were both observed, defining the germ-line Tsc2 mutation in the Eker rat as embryonal lethal and tumor predisposing mutation. To the best of our knowledge, this is the first report of rescue from a naturally occurring dominantly inherited cancer. This transgenic rescue system will be useful to analyze Tsc2 gene function, its relation to tumorigenesis in vivo, and genetic-environmental interactions in carcinogenesis.

Role of alternative splicing of the rat erythropoietin receptor gene in normal and erythroleukemia cells

An alternatively splicing of the rat erythropoietin receptor (EpoR) gene was identified in normal and erythroleukemia cells by the reverse transcription PCR method. Insertion of a 105 bp fragment at the region corresponding to the extracellular domain of rat EpoR was found. The insert sequence, which encodes additional 21 amino acids, is similar to that previously found in the mouse EpoR gene, however, has an additional 27 bp direct repeat. Due to the presence of a stop codon in the insert, the alternative transcript is translated to a truncated and soluble form of EpoR which is preferentially expressed in liver, spleen, kidney, heart, and bone marrow cells as well as cultured erythroleukemia cells. These findings suggest that alternative splicing of the EpoR gene may play an important role in proliferation and differentiation of rat erythroid cells.

[Development of comprehensive assessment system for elderly patients in a geriatric hospital]

Studies in the United States and Europe revealed that a comprehensive geriatric assessment is useful in the management and treatment of elderly disabled patients. In Japan, there are few reports of the development of such assessment. We examined the reliability of a scale designed to assess the performance of activities of daily living (ADL), a revised version of Hasegawa's Dementia Scale) HDSR, and a depression scale (GDS-15), using results from 140 patients over 65 years old who were admitted to our hospital from the end of January to early February 1994. The reliabilities of the ADL and HDSR scales were acceptable, but the kappa value of the GDS-15 was very low. The ADL score was low in patients with cerebrovascular diseases, dementia, and bone and joint problems, but the HDSR score was not low in the latter group. These results suggest that each disease has a characteristic pattern of impairments and disabilities. Although psychological assessment is essential and requires validation, a prospective study of outcomes in the evaluated elderly patients might also be fruitful.

Role of p53 tumor suppressor gene and Fas/Apo-1 in induction of apoptosis and differentiation of cancer cells

Recent studies have suggested that wild-type p53 blocks cell cycle progression near the G1-S boundary and is involved in both differentiation and apoptosis in many types of cells including cancer cells. p53 expression is enhanced upon DNA-damaging apoptotic stimuli while Fas/Apo-1, a member of the tumor necrosis factor receptor family expressed on cell surface, transduces a signal for apoptosis upon specific ligand or antibody engagement. We demonstrated that stable transfection of the wild-type p53 gene under the control of CMV promoter induced differentiation and apoptosis under restricted conditions in cancer cells, and often caused sensitization of p53-transfected cells to Fas/Apo-1 signal. To investigate the interaction between two major apoptotic pathways involving p53 and Fas/Apo-1 we have established a system that allows to induce wild-type p53 overexpression and apoptosis in cancer cells upon treatment with anti-Fas antibody. The system also allows to investigate other factors interacting with p53 and Fas/Apo-1, and should provide a clue to understanding the biological and biochemical aspects of apoptosis.

Viability of transgenic rat embryos after freezing and thawing

In-vivo viability of frozen-thawed embryos derived from transgenic rats, as well as the transmission and the expression of transgenes in the resultant newborn rats, was investigated. Three strains of transgenic rats, carrying human growth hormone gene connected downstream to the promoter region of the bovine alpha-lactalbumin gene (alpha LA/hGH), bovine beta-casein gene (beta CN/hGH) or bovine alpha-S1 casein gene (alpha S1CN/hGH), were used. Two-cell stage embryos (non-transgenic Wistar female x heterozygous transgenic male) were placed in 10% (v/v) dimethylsulfoxide (DMSO) solution and cooled from -7 to -30 degrees C at -0.5 degree C/min before being plunged into liquid nitrogen. After 2 to 4 years storage, the embryos were thawed by rapid warming. The intact embryos were transferred into the oviducts of Day 1 pseudopregnant recipients. The postthaw survival rate of frozen embryos was high in all 3 transgenic strains (88 to 92%), which was similar to that of control (non-transgenic) frozen embryos (95%). Development to newborn rats following transfer of embryos derived from the 3 strains (64 to 68%) was also similar to that of control embryos (60%). These transgenes (alpha LA/hGH, beta CN/hGH and alpha S1CN/hGH) were detected in the DNA extracts from tail tissue of the newborn rats, but the transmission rates (41, 23 and 32%, respectively) were lower than 50% which is expected in the Mendelian fashion. In a transgenic line carrying alpha S1CN/hGH, hGH levels of secretion into the milk of transgenic newborn rats derived from frozen-thawed embryos and her transgenic offspring were the same mg/ml-level as that of their founder rat. Two-step freezing of embryos derived from transgenic rats was therefore an effective method for the long-term cryopreservation of transgene.

Human choline acetyltransferase mRNAs with different 5'-region produce a 69-kDa major translation product

Choline acetyltransferase (ChAT, EC 2.3.1.6) is the biosynthetic enzyme for acetylcholine. We have previously shown that multiple ChAT mRNA species with different 5'-noncoding regions are expressed in the rat and mouse. However, the diversity of ChAT mRNA species in human has not completely been elucidated. In this work N1- and N2-type ChAT cDNAs were cloned from a human brain cDNA library and the N-exon located in the human ChAT gene. Polymerase chain reaction analysis indicates that four species of ChAT mRNAs (R-, N1-, N2- and M-types) are produced in human brain and spinal cord. In all human transcripts, the ATG initiation codon in the rat, mouse and pig was replaced by ACG, which does not serve as an initiation codon for translation. In vitro translation and mammalian expression analyses revealed that N1-, N2- and R-type mRNAs give rise to a single 69 kDa enzyme, while M-type mRNA produces both 82 and 69 kDa enzymes. The translation efficiency of M-type mRNA was lower than that of the other mRNA species. Moreover, the translation efficiency of human ChAT mRNAs was considerably lower than that of rat ChAT mRNA, suggesting that the ATG codons for human ChAT are unfavorable for translation initiation compared with the initiation codon for rat ChAT. These results provide rational explanations for the previous reports that human ChAT protein purified from the brain and placenta had 66-70 kDa molecular mass, and that ChAT activity in a single motor neuron of human was far lower than that of other vertebrates. Sequencing of monkey ChAT gene showed that the initiation ATG in rodent ChAT was also replaced by ACA in the monkey.

Successful long-term xenoperfusion of the pig liver: continuous administration of prostaglandin E1 and insulin

For clinical utilization of extracorporeal liver perfusion as an artificial liver assist device, we examined the possibility of long-term xenoperfusion of the pig liver by the continuous administration of prostaglandin E1 (PGE1) and insulin. After a 3-hr perfusion period, pig livers that were xenoperfused with human blood exhibited a drastic decrease in the perfusate volume, a progressive elevation of the hepatic artery pressure, a gradual deterioration of bile production, and a marked increase in the release of creatine kinase-BB component. The continuous administration of PGE1 (25 microg/hr) and insulin (1 U/hr) significantly improved these derangements (P<0.05) and allowed stable perfusion for up to 9 hr. This manipulation also inhibited leukocyte aggregation in the graft, the characteristic perfusate hemolysis, and acceleration of ketogenesis. Histological examination revealed that the interlobular edema and hemorrhage, characteristics of tissue injuries in xenogeneic hyperacute rejection, were markedly alleviated in the PGE1 and insulin-treated group. This study clarifies the finding that the combined administration of PGE1 and insulin is effective for long-term xenogeneic extracorporeal liver perfusion, with the graft viability well maintained.

Echographia as a symptom of interictal state in an epileptic patient: a case report

Echographia is a phenomenon in which a patient continuously translates verbal stimuli into writing. We encountered a patient with epilepsy who developed visual echographia during interictal periods. In this case, echographia was observed during two different periods, namely the period of disturbed consciousness after the epileptic seizure and the period of clear consciousness after suppression of the seizures. Disinhibition due to disturbance of the consciousness is considered to have been the cause of echographia in the former period. In the latter period, it is considered that echographia was caused by the release of lower function from suppression of upper function by brain dysfunction, as the after effect of status epilepticus. As echographia can be observed in epileptic patients, attention and careful observation by epileptologists is needed.

Alternative splicing of the erythropoietin receptor gene correlates with erythroid differentiation in rat hematopoietic and leukemic cells

An alternative splicing of the rat erythropoietin receptor (EpoR) gene was identified in normal and erythroleukemia cells. A 105 bp insert was found at a region corresponding to the extracellular domain of EpoR. The alternative transcript was translated to a soluble EpoR (EpoR-S) expressed in spleen, bone marrow, and cultured erythroleukemia cells in addition to the full-length EpoR (EpoR-F). One of the rat erythroleukemia sublines, K4DT, which partially lost erythroid phenotypes and manifested monocyte/macrophage characteristics also lacked EpoR-S expression. Thus, expression of EpoR-S may play an important role in differentiation of rat erythroid cells.