Primary biliary cirrhosis associated with membranous glomerulonephritis

A 33-year-old woman was admitted to our department for evaluation of liver dysfunction and proteinuria. A liver biopsy specimen showed ductular proliferation and moderate portal fibrosis indicating stage II primary biliary cirrhosis. A renal biopsy specimen showed mild to moderate mesangial cell proliferation without crescent formation or interstitial nephritis. Immunofluorescent staining revealed deposition of immunoglobulin G (IgG), third component of complement (C3), and Clq on glomerular basement membranes. The findings indicated stage I membranous glomerulonephritis. Administration of ursodesoxycholic acid together with prednisolone, azathioprine, and dipyridamole decreased proteinuria and improved cholestatic liver dysfunction.

[Life supports for terminal cancer patients]

An In-home medical care center was established at Tokyo Women's Medical University in 1997, and supported 14 cases that were treated at home. According to these cases, we understood that the terminal cancer patients and their family had various ways of thinking, especially misgivings about their surroundings. Causes of the misgivings were divided into 6 elements, such as experience, environment, situations, patients themselves, information and time management. To remove these uneasy feelings, we thought that our medical care center should play an important role in providing early consultation for cancer patients and their families. We concluded that the most important thing was collaboration with regional medical staff.

Glucose action 'beyond ionic events' in the pancreatic beta cell

For normal glucose homeostasis, insulin release by the pancreatic beta cell is vital. Until recently, it was thought that glucose-induced ionic events, such as closure of the ATP-sensitive K+ (KATP) channels, membrane depolarization, activation of the L-type voltage-dependent Ca2+ channels, Ca2+ influx and elevation of cytosolic free Ca2+, constitute the main signalling pathway in beta-cell stimulus-secretion coupling. However, since the discovery of 'non-ionic' glucose actions in the beta cell by the Aizawa and Henquin laboratories in 1991, data have accumulated that strongly indicate the physiological relevance of this signalling pathway. In this review, Toru Aizawa and colleagues discuss how the KATP channel-Ca2+ hypothesis was formulated, what was overlooked in the hypothesis, and then provide a comprehensive view of stimulus-secretion coupling in the beta cell, with an emphasis on non-ionic glucose actions.

Giant hepatic biloma following transcatheter oily chemoembolization in a patient with hepatic metastases from malignant pheochromocytoma

A 48-year-old woman developed hepatic metastases from malignant pheochromocytoma resected 8 years previously. Angiography revealed multiple tumor stains in the liver. Transcatheter oily chemoembolization using styrenomaleic acid neocarzinostatin and iodized oil was performed. The patient complained of severe right upper quadrant pain immediately following the transcatheter oily chemoembolization. Necrotizing cholecystitis developed on the 4th day post-transcatheter oily chemoembolization, hepatic infarction on the 12th day, and a biloma on the 19th day. Despite the administration of antibiotics and percutaneous transhepatic drainage, neither the volume of drainage nor the size of the biloma decreased. Biliary reconstruction was performed using a metallic stent, which decreased the size of the biloma.

[Medical cooperation between the in-home medical care and family physician]

It is important to exchange information about the patient between the family physician and medical staffs in the university hospital in home care, in order to create the good relationships among the patient, caregiver and the family physician. The main points are as follows: 1. Collaboration advice with the family physician before discharge. 2. Sharing medical treatment among medical staffs. 3. Sharing patient information with medical staffs. 4. Team approach.

Microbiology of the intestinal lymph follicle: a clue to elucidate causative microbial agent(s) in Crohn's disease

It has been suggested that microbial agent(s) are involved in the onset of Crohn's disease. None of the candidates, however, has been unequivocally demonstrated to be a causative agent. The macroscopically earliest lesion takes place in the lymph follicle, irrespective of the initial attack or relapse in Crohn's disease. Human leucocyte antigen-DR (HLA-DR) antigens are expressed on the epithelium around the lymph follicle even in areas endoscopically uninvolved in Crohn's disease. These observations make the lymph follicle critical in the onset of Crohn's disease. The lymph follicle is a port of entry of a variety of microbial agent(s), leading to the speculation that microbial agent(s) exist in the lymph follicle. Polymerase chain reaction (PCR) using universal primers designed from conserved regions of bacterial ribosomal RNA or techniques such as representational difference analysis, may well identify microbial agent(s) in the lymph follicle that are specific to Crohn's disease. The existence of bacteria in the lymph follicle is here indicated by preliminary studies.

Characterization, chromosomal localization, and genetic variation of the alpha subunit of porcine eighth component of complement

The complete amino acid sequence of the porcine alpha subunit of the eighth component of complement (C8A) was determined by characterizing the full length cDNA clone isolated from a porcine liver cDNA library. Porcine C8A was found to be similar to human and rabbit C8A in length, leader sequence, conserved cysteine residues, cysteine-rich modules, and overall sequence. Differences in the amino acid sequence among the three species were detected in the proposed candidate site for CD59 recognition (amino acids 352-389). The porcine C8A gene was physically mapped to chromosome 6q33-35 by in situ hybridization using the porcine bacterial artificial chromosome (BAC) clone as a hybridization probe. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of C8A was performed using the restriction enzyme Hha I. Distribution of the alleles was determined in pigs (n = 173) of several different breeds. Estimates of allele frequency of the 201 bp fragment were 0.22,.0.43,.0.04,.0.50,.0.58,.0.50,.0.98, and 0.91 in Landrace, Large White, Duroc, Berkshire, Jinhua, Crown Miniature Pig, wild boar, and Meishan, respectively.

[Aging and Hashimoto's thyroiditis]

Analysis of patients with persistent hypothyroidism due to Hashimoto's thyroiditis suggested that metabolism of thyroxine (T4), including deiodination to triiodothyronine (T3), was reduced in the elderly. The increase in the serum levels of T4 after oral administration of T4 was augmented in the elderly, whereas increase in the serum T3 level was not. Possibly due to the reduction in the pituitary deiodinase, suppression by T4 administration of serum thyrotropin (TSH) level was the same in elderly as in younger subjects despite a larger increase in the serum levels of T4 in the elderly. Consequently, the amount of T4 required to maintain a normal serum TSH level did not differ between elderly and younger subjects. Other characteristics of elderly patients with Hashimoto's thyroiditis were that goiter size was smaller, that hypothyroidism was more frequent, and that Graves' disease was less frequent.

Differentiation of benign from malignant nodules by accumulation of Tc-99m pertechnetate using TI-201 delayed scans

Thyroid carcinoma usually is characterized by a nonfunctioning or "cold" nodule depicted on the Tc-99m scan. Twelve patients with functioning "hot" thyroid nodules underwent thyroidectomy (nine hemithyroidectomies, two nodulectomies, and one subtotal thyroidectomy). Histologic examination revealed that five patients (42%) had malignant nodules (papillary carcinoma in two and follicular carcinoma in three). Of the seven patients with benign nodules, five had follicular adenoma and two had adenomatous hyperplasia. TI-201 scanning (early and delayed) was performed at the same time as Tc-99m scanning. Only one of the seven benign nodules showed accumulation on the delayed TI-201 scan, whereas all five malignant nodules showed accumulation. The delayed TI-201 scan is useful for the differentiation of benign from malignant nodules that show accumulation of Tc-99m pertechnetate.

Portal-systemic encephalopathy from a spontaneous gastrorenal shunt diagnosed by three-dimensional computed tomography and treated effectively by percutaneous vascular embolization

A 67-year-old man with a portal-systemic shunt confirmed by three-dimensional computed tomography (3D-CT) was successfully treated by percutaneous vascular embolization. The patient had aggravated loss of memory, disorientation, and hyperammonemia. A gastrorenal shunt 16 mm in diameter was found by 3D-CT reconstructed by helical computed tomography (CT). Embolization was performed only in the shunt percutaneously through the inferior vena cava. One year after the embolization, no recurrence of portal-systemic encephalopathy and no portal hypertension have appeared, and the clinical course has been good.

Free radical scavenging activity of fermented papaya preparation and its effect on lipid peroxide level and superoxide dismutase activity in iron-induced epileptic foci of rats

Fermented papaya preparation is a natural health food that has been commercially sold in Japan for 2 years. It is made by yeast fermentation of Carica Papaya Linn. We examined the antioxidant action of the fermented papaya preparation on free radicals and lipid peroxidation. Free radicals have been related with aging and diseases, such as cancer, diabetes and especially in neurological disorders, for example, Parkinson's disease or Alzheimer's disease. A diet including variable antioxidant foods may therefore help to prevent these illnesses. The free radical scavenging activity of the fermented papaya preparation was examined using an electron spin resonance (ESR) spectrometer. Fermented papaya preparation (50 mg/ml) scavenged 80% of hydroxyl radicals (.OH) as spin adducts of spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) (5.27 x 10(15)spins/ml) generated by Fenton reagents. The value of IC50 was 12.5 mg/ml. The oral administration of the fermented papaya preparation for 4 weeks decreased the elevated of lipid peroxide levels in the ipsilateral 30 min after injection of iron solution by iron into the left cortex of rats. The fermented papaya preparation also increased superoxide dismutase activity in the cortex and hippocampus of them. These results suggest that the fermented papaya preparation has antioxidant actions and that it may be prophylactic food against the age related and neurological diseases associated with free radicals.

Nutrient augmentation of Ca2+-dependent and Ca2+-independent pathways in stimulus-coupling to insulin secretion can be distinguished by their guanosine triphosphate requirements: studies on rat pancreatic islets

To delineate the underlying mechanisms by which glucose augments both Ca2+-dependent and Ca2+-independent insulin release, the latter induced by the simultaneous activation of protein kinases A and C, we examined the effects of GTP depletion by mycophenolic acid (MPA), an inhibitor of GTP synthesis, on the augmentation of insulin release from rat pancreatic islets. MPA treatment reduced GTP content by 30-40% and completely abolished glucose-induced augmentation of Ca2+-independent insulin release. Thus, this pathway is extremely sensitive to a decrease in cellular GTP content. Complete inhibition was also observed in islets treated with MPA plus adenine, to maintain ATP levels, under which conditions GTP is selectively depleted. Provision of guanine, which increases the activity of a salvage pathway for GTP synthesis and normalizes GTP content, completely reversed the inhibitory effect of MPA. Neither glucose utilization nor glucose oxidation was affected by MPA. The augmentation of Ca2+-independent insulin release by several other metabolizable nutrients including alpha-ketoisocaproic acid (KIC) was also inhibited by MPA. In sharp contrast, augmentation of Ca2+-dependent insulin release by KIC was resistant to GTP depletion, indicating that nutrient-induced augmentation of the Ca2+-dependent- and Ca2+-independent secretory pathways can be differentiated by GTP dependency. We interpret these data in accord with current knowledge concerning the two known stimuli for exocytosis, Ca2+ and GTP (independently of Ca2+). We propose that both Ca2+-dependent and Ca2+-independent augmentation occurs via one metabolic pathway acting upon Ca2+- and upon GTP-stimulated exocytosis. Activation of PKA and PKC stimulates the GTP-sensitive exocytosis.

Palmitate and myristate selectively mimic the effect of glucose in augmenting insulin release in the absence of extracellular Ca2+

Under Ca2+-free conditions, activation of the pancreatic beta-cell with forskolin and 12-O-tetradecanoylphorbol 13-acetate (TPA) is permissive for the augmentation of insulin release by glucose and other nutrients. The ability of fatty acids to mimic the effect of glucose and thereby augment insulin secretion in the absence of extracellular Ca2+ is the focus of the present study. In the absence of extracellular Ca2+, glucose, palmitate, and myristate had no effect on insulin release. When, under Ca2+-free conditions, the islets were treated with forskolin to raise cyclic AMP levels and activate protein kinase A and with TPA to activate protein kinase C, glucose, palmitate, and myristate all augmented release to approximately the same extent. No other saturated fatty acid with chain lengths in the C = 6-22 range augmented the release of insulin. This selective augmentation by palmitate or myristate was not seen with forskolin alone, and was seen slightly with TPA and strongly with the combination of forskolin and TPA. The response, which developed slowly and had a time course similar to that of second-phase insulin release, was abolished by the physiological inhibitor norepinephrine. The results suggest that the mechanism underlying the Ca2+-independent augmentation of insulin release by glucose and other nutrients involves the proposed malonyl-CoA/long-chain acyl-CoA pathway with specificity for myristoyl- and palmitoyl-CoA esters and/or their derivatives.

A very-high-density lipoprotein with clotting ability from hemolymph of sand crayfish, Ibacus ciliatus

A very-high-density lipoprotein (VHDL) with a density of 1.27-1.29 g/ml was the most abundant lipoprotein in the hemolymph of the sand crayfish Ibacus ciliatus. The VHDL isolated by a density gradient ultracentrifugation consisted of 94% protein and 6% lipid reflecting its high density, and phospholipid was a predominant lipid component. The VHDL had an apolipoprotein of molecular mass 195 kDa and its N-terminal amino acid sequence was identified as follows: LQPGLEYQYRYNGRVAA. This sequence was similar to those of clotting proteins from the spiny lobster Panulirus interruptus and the freshwater crayfish Pacifastacus leniusculus. Transglutaminase and Ca2+ also induced the VHDL to clot. Considering large amounts of VHDL in the hemolymph of sand crayfish, the VHDL not only functions as lipid carrier but plays an important role in the defense process of crustacea.

Effect of folic acid on thymidylate synthase and thymidine kinase in regenerating rat liver after partial hepatectomy

The effects of folic acid on liver regeneration after partial hepatectomy were investigated. The injection of folic acid inhibited the increases in the activities of thymidylate synthase and thymidine kinase in regenerating rat liver at 24 h after partial hepatectomy, with a concomitant reduction in DNA content. Northern blot analysis showed that this inhibition was due to the delay of the elevation of the mRNA levels of thymidylate synthase and thymidine kinase after partial hepatectomy. At 48 and 72 h, after partial hepatectomy, the thymidylate synthase activities in the folic acid injected rats increased to about 1.9- and 1.7-fold the corresponding control level, respectively, while thymidine kinase activities were similar to the control. Immunoblotting assay indicated that the increases in the thymidylate synthase activity at 48 and 72 h after partial hepatectomy were caused by a three fold increase in its protein level. Folic acid suppressed chymotryptic hydrolysis of thymidylate synthase. These suggest that folic acid increases the protein level of thymidylate synthase, at least in part, through protection against proteolysis.

Reversible disruption of cell-matrix and cell-cell interactions by overexpression of sialomucin complex

Sialomucin complex (SMC) is a large, heterodimeric glycoprotein complex composed of mucin (ASGP-1) and transmembrane (ASGP-2) subunits and expressed abundantly on the cell surface of ascites 13762 rat mammary adenocarcinoma cells. We have isolated recombinant cDNAs containing different numbers of ASGP-1 mucin repeats, which can be expressed as protein products with variable lengths. To study the anti-adhesive effect of SMC, these cDNAs were transfected into human cancer cell lines. Using a tetracycline-responsive, inducible expression system, we demonstrated that the overexpression of SMC induces morphology changes, cell detachment, and cell-cell dissociation of transfected A375 human melanoma cells in culture. The transition between the adherent and suspension states of the cells is fully reversible and dependent on the SMC expression level. The anti-adhesion effect of SMC was further analyzed kinetically by measuring the cell adhesion of transfected A375 melanoma and MCF-7 breast cancer cell lines to fibronectin, laminin, and collagen IV, demonstrating that SMC disrupts integrin-mediated cell adhesion to extracellular matrix proteins. The degree of this anti-adhesion effect was dependent on the number of mucin repeats in the SMC molecule as well as the level of cell surface expression.

Augmentation of insulin release by glucose in the absence of extracellular Ca2+: new insights into stimulus-secretion coupling

Glucose stimulates insulin secretion in the pancreatic beta-cell by means of a synergistic interaction between at least two signaling pathways. One, the K(ATP) channel-dependent pathway, increases the entry of Ca2+ through voltage-gated channels by closure of the K(ATP) channels and depolarization of the beta-cell membrane. The resulting increase in [Ca2+]i stimulates insulin exocytosis. The other, a K(ATP) channel-independent pathway, requires that [Ca2+]i be elevated and augments the Ca2+-stimulated release. These mechanisms are in accord with the belief that glucose-stimulated insulin secretion has an essential requirement for extracellular Ca2+ and increased [Ca2+]i. However, when protein kinases A and C are activated simultaneously, a large effect of glucose to augment insulin release can be seen in the absence of extracellular Ca2+, under conditions in which [Ca2+]i is not increased, and even when [Ca2+]i is decreased to low levels by intracellular chelation with BAPTA. In the presence or absence of Ca2+, there are similarities in the characteristics of augmentation of insulin release that suggest that only one augmentation mechanism may be involved. These similarities include time course, glucose dose-responses, augmentation by nutrients other than glucose such as alpha-ketoisocaproate (alpha-KIC), and augmentation by the fatty acids palmitate and myristate. However, augmentation in the presence and absence of Ca2+ is distinctly different in GTP dependency. Therefore, exocytosis under these two conditions appears to be triggered differently-one by Ca2+ and the other by GTP or a GTP-dependent mechanism. The augmentation pathways are likely responsible for time-dependent potentiation of secretion and for the second phase of glucose-stimulated insulin release.

The effects of phaco-emulsification-aspiration and intra-ocular lens implantation on the pupil: pupillographic and pharmacologic study

The authors report postoperative change in pupil diameter and pupil dynamics after phaco-emulsification-aspiration and intra-ocular lens implantation by comparing the operated eye and non-operated eye in 20 patients who received unilateral surgery. Miosis was noted in the operated eye throughout the postoperative period in the dark, and also in the light at an early stage after the operation. Both the maximal constriction velocity and maximal dilatation velocity of the light reflex decreased postoperatively, but the constriction velocity alone was accelerated 1 or 2 weeks after the operation. In the drug instillation test, pupillary responses to both neosynephrine and pilocarpine were decreased, indicating damage both to the dilator and sphincter muscles. Since no hypersensitivity of the pupil was noted, lesions in the axonal fibres and denervation were judged to be absent. Postoperative miosis is believed to be explained by irreversible damage to the dilator muscle, as well as by the transient effects of inflammatory substances.

[Rapid detection of Shiga-like toxin gene in feces with rapid-cycle polymerase chain reaction]

A rapid detection for Shiga-like toxin in feces was developed with the nucleic acid extraction method by silicondioxide-guanidine thiothianate and rapid-cycle polymerase chain reaction by RapidCycler (model 1002; Idaho Technology, RC-PCR here after). Twenty-two fecal samples that were collected from patients with diarrhoea caused by E. coli O157:H7 and frozen for 6 months were examined directly by RC-PCR, conventional PCR assay using by ThermalCycler 9600-R (Roche, TC-PCR here after) and by the culture method using tellurite-cefixime sorbitol MacConkey (direct method). These examinations were done also after being injected into TCV-TSB and incutated at 35 degrees C overnight (indirect method). The sensitivity of RC-PCR and TC-PCR using a diluted suspension of broth enriched at 35 degrees C overnight were 4.1 pg and 410 fg, respectively. Positive results in the direct method were obtained in 7 for RC-PCR, 10 for TC-PCR and 5 for culture. Positive results on indirect assay were obtained in 9 for RC-PCR, 9 for TC-PCR and 7 for culture. It was demonstrated that the RC-PCR assay was able to detect Shiga-like toxin gene in feces in less than 90 minutes after being received at the laboratory.

[Rapid detection of Escherichia coli 0157:H7 in feces by latex agglutination and immunochromatographic assay]

The rapid detection method of Escherichia coli O157 in feces by using the latex agglutination test kit (Prolex; Pro Lab Diagnostics) and the immunochromatic assay kit (NOW EH. E. coli; Binax) was studied. 176 fecal samples obtained from 154 healthy men and 22 patients who had diarrhea by E. coli O157 were examined. Tellurite cefixim sorbitol MacConkey (TC-SMAC), Prolex and NOW were used for studies and also these were done after the enriched culture by tellurite cefixime vancomycin toriptic soy broth (TCV-TSB). In the direct inoculation, 5 (23%) of 22 samples, 7 (32%) and 9 (41%), and after the enriched culture, 7 (32%), 10 (46%) and 11 (50%) were positive by culture, Prolex and NOW, respectively. On the other hand, 154 samples from healthy men were all negative in the direct inoculation, but in the enriched culture, 7 of 40 (18%) were positive by NOW. These samples were negative by boiled (100 degrees C, 15 minutes). Our results indicated that Prolex and NOW were useful for accurate and rapid diagnosis of E. coli O157 enteritis, and more sensitivity results were obtained with the enrichment broth.

Alterations in type-1 serine/threonine protein phosphatase PP1alpha in response to B-cell receptor stimulation

In response to stimulation of B-cells through cell surface IgM, the activity of the serine/threonine protein phosphatase PP1, but not PP2A, was transiently decreased and reached a minimum 10-20 min after the stimulation. The decrease was more profound in the immature B-cell line WEHI-231, than in the mature B-cell line BAL-17. Under these conditions, PP1alpha, an isoform of PP1, showed unique alterations in the patterns of several spots with distinct isoelectic points in the Western blot after two-dimensional electrophoresis, whereas another isoform, PP1delta, did not show any alteration. PP1gamma1 and PP1gamma2 were not detected in B-cells. Similar alterations in these spots were observed in B-cells stimulated by PMA. When partially purified PP1 consisting of PP1alpha and PP1delta was incubated with [gamma-32P]ATP and PKC, radioactive spots of PP1alpha could be detected, but no spot of PP1delta was detected. Because differences in sequence among PP1 isoforms are mostly restricted to their C-terminals, phosphorylation rates of the C-terminal peptides containing the PKC-phosphorylation motif were compared. The C-terminal peptide of PP1alpha is a better substrate for PKC than those of PP1gamma1 and PP1gamma2, and is phosphorylated at the serine residue corresponding to Ser-325 of PP1alpha. The corresponding C-terminal region of PP1delta does not contain the phosphorylation site. On the other hand, there was a large difference in subcellular distribution of PP1delta, but not PP1alpha, between immature and mature B-cells. From these results, it was strongly suggested that PP1alpha is involved, via phosphorylation by PKC, in the regulation of signal transduction in response to the stimulation of B-cells through cell surface IgM.

A multicentre randomized controlled trial of recombinant interferon-alpha-2a in the treatment of patients with chronic hepatitis C

Sixty-one chronic hepatitis C patients were randomly assigned to receive either 6 x 10(6) or 9 x 10(6) U of recombinant interferon-alpha-2a (IFN alpha-2a) six days a week for the first two weeks of treatment, followed in both cases by 6 x 10(6) U three days a week for the next 22 weeks. In the low dose group, 11 patients showed a complete response maintained for at least six months, 12 responded but then relapsed and nine did not respond; the corresponding figures in the high dose group were 10, 15 and five patients, respectively. The differences between groups are not statistically significant. Thus, this study provides no evidence of therapeutic benefit from increasing the initial dose of IFN alpha-2a. In both treatment groups, complete responders had significantly lower pretreatment viral titres than nonresponders and were significantly more likely to be infected by type 2a versus type 1b virus.

Utility of hepatitis C virus RNA levels for predicting the therapeutic efficacy of interferon

We studied the levels of serum hepatitis C virus (HCV)-RNA, the HCV genotype before interferon therapy, and the kinetics of serum HCV-RNA at the initial stages of therapy to determine their utility in predicting the therapeutic efficacy of interferon in 44 patients with chronic hepatitis C infection. We also looked at the efficacy of repeated interferon treatment in relation to the kinetics of serum HCV-RNA. The level of serum HCV-RNA determined by a branched DNA probe assay before interferon treatment and that by a reverse transcription nested polymerase chain reaction assay during the initial stages of interferon administration were useful for predicting the efficacy of treatment. Furthermore, detection of serum HCV-RNA by the reverse transcription nested polymerase chain reaction assay after the completion of interferon therapy indicated relapse at its earliest stage. In patients who experience relapse, repeated treatment with an appropriate dose of interferon before an increase in viral levels may increase the proportion of complete responses.

Relationships of subunits of type-1 serine/threonine protein phosphatase to morphology and aggregation of B cells

To elucidate the roles of serine/threonine protein phosphatases PP1 and PP2A in the morphological changes of B-lymphocytes during development and in immune responses, we investigated alterations of protein levels of catalytic subunits of PP1 and PP2A and regulatory subunits of PP1 including M130/M133, inhibitor-1 (I-1) and inhibitor-2 (I-2) in B-cell lines at different maturational stages and during their aggregation induced by phorbol myristate acetate (PMA). The protein levels of PP1delta and/or M130/M133 were significantly lower in B-cell lines without pseudopods, WEHI-231, BAL-17, Daudi, and CESS, than in those with pseudopods, Bcl.1, A20, M12, and SKW6.4, whereas the amounts of PP1alpha and PP2A were similar among them. During aggregation of A20 and CESS cells induced by PMA, an activator of PKC, the amount of PP1delta was progressively decreased, and this decrease was blocked by H7, an inhibitor of PKC. The amount of PP1alpha was constant under these conditions. Okadaic acid, an inhibitor of PP1 and PP2A, also induced aggregation of A20 cells at concentrations sufficient to inhibit PP1, but not at lower concentrations that inhibit PP2A alone. These results suggest that myosin light chain phosphatase composed of PP1delta and M130/M133 is involved in the maintenance and regulation of cytoskeletal structures in B-lymphocytes.

Sarcoid reaction in thyroid diseases: report of a case of thyroid carcinoma demonstrating sarcoid reaction in regional lymph nodes

We describe an extremely rare case of thyroid carcinoma accompanied by sarcoid reaction in regional lymph nodes. The patient, a 40-year-old woman, was found to have anterior neck swelling during a routine medical examination. Physical examination revealed a bad movable and firm nodule measuring 3.5 x 2.5 cm in the right thyroid lobe. Examination of a fine-needle aspiration cytology of the nodule suggested papillary carcinoma of class V. Right lobectomy and isthmectomy with neck dissection were performed. Histopathological examination of the resected specimens revealed papillary carcinoma accompanied by metastatic foci in right perithyroidal lymph nodes and non-caseous sarcoid-like granulomas in pretracheal, right upper internal deep cervical and submandibular lymph nodes. We concluded that these granulomas were due to a sarcoid reaction associated with thyroid carcinoma, after performing examinations to rule out the possibility of systemic sarcoidosis.

Molecular cloning and expression of a rat cDNA encoding 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase

The cDNA of a 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase (AICARFT/IMPCHase) was isolated from rat liver RNA by reverse transcription and the polymerase chain reaction (PCR). The rat AICARFT/IMPCHase cDNA included 1928 bp containing a coding region of 1779 bp for a 592-amino acid polypeptide (Mr = 64 200). Rat and human AICARFT/IMPCHase cDNAs show 84 and 91% homology at the nucleotide and amino acid sequence level, respectively. The protein produced by the rat cDNA using pET-expression system catalysed the penultimate and final steps of de novo purine biosynthesis. Northern analysis identified a 2.8-kb AICARFT/IMPCHase mRNA and the level of the AICARFT/IMPCHase transcripts increased markedly at 24 h after partial (70%) hepatectomy.

MAZ, a Myc-associated zinc finger protein, is essential for the ME1a1-mediated expression of the c-myc gene during neuroectodermal differentiation of P19 cells

To investigate whether MAZ (Myc-associated zinc finger protein) affects the expression of the c-myc gene during the retinoic acid-induced (RA-induced) neuroectodermal differentiation of P19 embryonal carcinoma (EC) cells, we introduced a CAT reporter construct, human c-myc promoter/CAT (pMyc2CAT), and a mutant CAT derivative that lacked an ME1a1 site (pMyc1CAT) into P19EC cells to monitor the promoter activity of the c-myc gene. The expression of CAT in pMyc2CAT-transformed cells declined fivefold after 24 h in the presence of RA, returned to the normal level within 48 h, and decreased again to below 20% of the normal level after 96 h. By contrast, the expression of CAT in pMyc1CAT-transformed cells did not return to the normal level after 48 h in the presence of RA. In addition, an electrophoretic mobility shift assay (EMSA) with ME1a1 DNA as probe demonstrated that the kinetics of the DNA-binding activity of MAZ were closely correlated with the changes in the expression of CAT from the c-myc promoter/CAT gene during the differentiation of P19EC cells. Taken together, these results suggest that MAZ plays a key role in the transient increase in the expression of the c-myc gene after 48 h of exposure to RA during the neuroectodermal differentiation of P19EC cells.

Pilot study of ofloxacin and interferon-alpha combination therapy for chronic hepatitis C without sustained response to initial interferon administration

A controlled trial comparing combination therapy with ofloxacin (OFLX) and interferon (IFN) versus IFN monotherapy was conducted in patients with chronic hepatitis C who failed IFN therapy. Twenty patients were assigned randomly to two groups. Equal doses of recombinant IFN alpha-2b were administered to each group for 24 weeks. For the IFN plus OFLX group, OFLX was administered for 12 weeks at a daily dose of 600 mg. Levels of hepatitis C virus RNA declined significantly from the first month after the start of IFN treatment compared with those before administration in both groups. Serum alanine aminotransferase levels were significantly lower in the IFN plus OFLX group at two and six months after the start of treatment than levels in the IFN group. The fraction of subjects whose levels of serum ALT normalized was also higher in the IFN plus OFLX group. Larger clinical trials should be undertaken.

Induction of a 72-kDa heat shock protein and cytoprotection against thioacetamide-induced liver injury in rats

Heat shock proteins are ubiquitous intracellular proteins induced by various physiological stress-related events. A 72-kDa heat shock protein (HSP72) has been reported to be an endogenous cytoprotectant in variety of cells in vitro. In order to study the cytoprotective function of HSP72 in the liver, the effect of preinduction of HSP72 in rat liver by systemic hyperthermia on thioacetamide-induced hepatic injury was investigated in this study. Expression of HSP72 in the liver was investigated by immunoblot and densitometric analysis. Rats were injected with thioacetamide (100 mg/kg, subcutaneously) with or without preinduction of HSP72 by hyperthermia. Serum AST and ALT concentrations were measured before and after thioacetamide injection in both group. Histologic alteration of the liver was evaluated also. Systemic hyperthermia (42.5 degrees C, 20 min) significantly induced HSP72 in the liver. Thioacetamide-induced hepatic injury was clearly prevented by preinduction of HSP72 by hyperthermia. Prevention of hepatocyte damage was more clear in the area around central veins where HSP72 induction was apparent. Our findings might suggest that HSP72 has an important function in the liver with respect to cytoprotection. These results might be important for understanding the mechanism of "adaptive cytoprotection" in the liver mediated by the function of heat shock proteins as "molecular chaperons" as reported in vitro.

Ethanol represses thymidylate synthase and thymidine kinase at mRNA level in regenerating rat liver after partial hepatectomy

The effects of ethanol on liver regeneration after partial hepatectomy were investigated. The injection of ethanol inhibited the increases in the activities of thymidylate synthase and thymidine kinase in regenerating rat liver at 24 h after partial hepatectomy in a dose-dependent manner, with a concomitant reduction in DNA content. Northern blot analysis showed that the inhibition of thymidylate synthase and thymidine kinase activities was caused by comparable decreases in their mRNA levels. The immunoblotting assay confirmed the protein levels of thymidylate synthase and thymidine kinase as proportional to the activity and mRNA levels. These findings suggest that ethanol inhibits DNA synthesis by the repression of mRNA levels of dTMP-synthesizing enzymes during liver regeneration.

A repeated-dose dermal toxicity study of hydrophobically modified hydroxypropyl methylcellulose in rats

A six-month repeated-dose dermal toxicity study followed by a 30-day recovery test of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC), a new cellulose derivative used as a thickener for topical pharmaceuticals, was conducted using rats. Aqueous paste of HM-HPMC was applied to the skin of rats once daily at dose levels up to 60 mg/kg/day, which was the highest dose that could be administered. Items checked included general signs, urinalysis, hematology, ophthalmology, and histopathology. One rat died during the administration period owing to a malignant tumor in the hemopoietic system, which was not attributed to the test substance. Statistically significant differences were found in some test results, but those were not dose-dependent and were considered to be incidental or spontaneous. It was concluded that the test substance was not toxic upon chronic dermal administration at dose levels up to 60 mg/kg/day.

Cytotoxicity of organochlorine pesticides and lipid peroxidation in isolated rat hepatocytes

The cytotoxicity and lipid peroxidation of pesticides containing a halogen group were examined in isolated rat hepatocytes. We examined 9 pesticides of 3 different representative chemical families, chlorinated aromatic fungicides (pentachlorophenol (PCP), pentachloronitrobenzene (PCNB), chlorothalonil, fthalide), polyhaloalkylated thio fungicides (dichlofluanid, captan) and diphenyl ether herbicide (2,4-dichlorophenyl 4-nitrophenyl ether (NIP), 4-nitrophenyl2,4,6-trichlorophenyl ether (CNP), chlomethoxynil). The contents of the hydroperoxides in phospholipid, phosphatidylcholine hydroperoxide (PCOOH) and phosphatidylethanolamine hydroperoxide (PEOOH) were determined by the HPLC-chemiluminescence (CL-HPLC) method, which is sensitive and specific for lipid hydroperoxide. Chlorothalonil, dichlofluanid and captan were the most potent cytotoxicants evaluated by lactate dehydrogenase (LDH) leakage. PCP, NIP and CNP exhibited intermediate cytotoxicity. PCNB, fthalide and chlomethoxynil showed low cytotoxicity. The cellular phospholipid hydroperoxide (PCOOH and PEOOH) levels were remarkably increased by chlorothalonil (PCOOH, 23 times and PEOOH, 7 times), dichlofluanid (PCOOH, 523 times and PEOOH, 22 times) and captan (PCOOH, 518 times and PEOOH, 16 times) as compared with the control group. The PCOOH content was slightly increased by PCP (4.8 times) and NIP (6.3 times), whereas the other 4 pesticides did not change the phospholipid hydroperoxide level. Severe cytotoxicity was observed with a remarkable increase of phospholipid hydroperoxide by chlorothalonil, dichlofluanid and captan.

An early insulin intervention accelerates pancreatic beta-cell dysfunction in young Goto-Kakizaki rats, a model of naturally occurring noninsulin-dependent diabetes

This study was designed to delineate the nature of beta-cell dysfunction in a model of genetically determined nonobese diabetes, the Goto-Kakizaki (GK) rat. Pancreatic beta-cell function was analyzed immediately after weaning and 5 weeks thereafter, comparing animals with or without insulin treatment during the interval. In 3.5-week-old GK rats, fasting plasma glucose was mildly elevated with normoinsulinemia, and the islet insulin content was reduced by 33%. When incubated with 3-30 mM glucose in vitro, the GK rat islets showed reduced glucose sensitivity, i.e. the EC50 values were 19.5 and 15.9 mM, and the Hill constants for the positive cooperativity 2.1 and 4.2 in the islets of GK and the control rats, respectively. On the other hand, the maximum response to glucose was not attenuated when reduced islet insulin content was considered. In 8.5-week-old GK rats hyperglycemia worsened and glucose-stimulated insulin release by the islets more severely impaired. A daily insulin injection from the 3.5-8.5 weeks of age significantly lowered plasma glucose in the GK rat, accompanied by a marked suppression of both basal (with 3 mM glucose) and glucose (6-30 mM)-stimulated insulin release by the islets. In the GK rat, beta-cell dysfunction develops by the age of 3.5 weeks, and insulin treatment during the subsequent 5 weeks accelerates its progression.

Two signaling pathways, from the upper glycolytic flux and from the mitochondria, converge to potentiate insulin release

In the rat pancreatic beta cell, low concentrations of glucose potentiate D-glyceraldehyde (GA)-induced insulin release without any potentiation of the triose-induced elevation of cytosolic free Ca2+ concentration. Namely, 2-3 mM glucose strongly potentiates 5 mM GA-induced insulin release, and the combination of stimulatory concentration of glucose (10 mM) and 5 mM GA elicits far more than additive insulin release: this glucose action is independent of ATP-sensitive K+ channel closure because it can be seen in the presence of diazoxide, an opener of the K+ channel. The triose-induced elevation of cytosolic free Ca2+ concentration was not potentiated by the presence of 3 mM glucose, and oxidation of labeled GA by the islet cells was not enhanced by the presence of glucose. The glucose action can be mimicked by mannose, but not by galactose, and was suppressed by inhibition of glucose phosphorylation with mannoheptulose or 2-deoxyglucose. Glucose also potentiates 2-ketoisocaproate-induced insulin release. In contrast, a combination of GA and 2-ketoisocaproate elicits only additive insulin release. Strikingly, 3 mM glucose does not potentiate insulin release in response to a depolarizing concentration of K+. Therefore, at least two signal pathways, one from upper glycolytic flux and one from mitochondrial metabolism, must converge to provide the potentiation of insulin release. We conclude that the upper glycolytic flux, acting at a site unrelated to the elevation of cytosolic free Ca2+, potentiates insulin release triggered by triose and mitochondrial fuels.

Sialomucin complex, a heterodimeric glycoprotein complex. Expression as a soluble, secretable form in lactating mammary gland and colon

Ascites 13762 rat mammary adenocarcinoma cells express abundantly on their cell surfaces a heterodimeric glycoprotein complex composed of a sialomucin ascites sialoglycoprotein (ASGP)-1 and a transmembrane subunit ASGP-2. The latter, which contains two epidermal growth factor-like domains, binds the receptor tyrosine kinase p185(neu), suggesting that the complex is bifunctional as well as heterodimeric. Immunoblot analyses using monoclonal antibodies prepared against the complex demonstrate high levels of expression in rat lactating mammary gland and colon. Immunolocalization studies with anti-ASGP-2 indicate that ASGP-2 is present in these two tissues in the apical regions of secretory epithelial cells. Both mammary gland and colon contain a soluble, secretable form of ASGP-2, which is not found in the ascites cells; milk and mammary gland also have the membrane form. Immunoblot analyses using a COOH-terminal-specific polyclonal antibody indicate that the soluble form of ASGP-2 is missing its COOH-terminal domains. Both the soluble and membrane forms of ASGP-2 are similar to the membrane-associated form from the 13762 adenocarcinoma with respect to Mr, antigenicity, and association with ASGP-1. The presence of ASGP-1 in milk suggests that it is a candidate for the uncharacterized high Mr milk mucin, MUCX. ASGP-2 expression is up-regulated in mammary gland during pregnancy, because it is undetectable in virgin and early pregnant rats but abundant in the gland from late pregnant and lactating animals. However, compared with the lactating mammary gland, the 13762 ascites cells overexpress ASGP-2 by more than 100-fold, which may contribute to their malignancy. These combined results indicate that sialomucin complex is a unique secreted product in the mammary gland and colon, whose behavior is different from that in the mammary ascites tumors, and which may play important roles in mammary and intestinal physiology.

Analysis of the pancreatic beta cell in the mouse with targeted disruption of the pancreatic beta cell-specific glucokinase gene

This is the first systematic study on the pancreatic beta cell function in the heterozygous mouse with targeted disruption of the beta cell glucokinase gene. The heterozygotes' beta cell displayed the following characteristics: (1) impaired glucose sensitivity with normal glucose responsiveness, (2) poor discrimination of alpha and beta glucose anomers, and (3) normal response to glucose in the presence of 25 mM K+ and 150 microM diazoxide. Both the first and the second phases of glucose-stimulated insulin release were depressed. Although the heterozygotes were mildly hyperglycemic, insulin treatment further suppressed beta cell function, implying the beta cell glucose toxicity is not the cause of impaired glucose sensitivity. The data are compatible with the glucokinase glucose sensor concept inasmuch as glucose sensitivity is reduced in the heterozygotes' beta cell. The anomeric malaise and preservation of the ATP-sensitive K+ channel-independent glucose action were considered due to chronic hyperglycemia.

The betaHC-9 pancreatic beta-cell line preserves the characteristics of progenitor mouse islets

betaHC-9 is a pancreatic beta-cell line that is derived from the hyperplastic islets of transgenic mice that express the simian virus 40 tumor antigen gene in the islets. This cell secretes insulin in response to glucose in a concentration-dependent manner. Maximal and half-maximal concentrations were approximately 20 and approximately 10 mmol/l, respectively, with a maximal fractional release that averaged 3.7% of the total cellular insulin content per 60 min. The cellular insulin content was 3-9% of the content of mouse islet cells. Under perifusion conditions, high glucose concentrations induced a sharp first phase that lasted approximately 10 min and a succeeding second phase of sustained release, as exhibited by mouse islets. The cells did not show a rising second phase as seen with rat islets. This biphasic response was obtained without the need for activators of protein kinase A such as forskolin or 3-isobutyl-1-methylxanthine. The dose-dependency and the phasic response to glucose were essentially invariable up to passage 38 but thereafter declined. The cells respond to various well-known stimulators of insulin secretion, including leucine and arginine; to modulators such as carbachol, glucagon-like peptide I, and pituitary adenylyl cyclase activating polypeptide; and to the inhibitors norepinephrine, somatostatin, and galanin. The pharmacological agents glibenclamide, 12-O-tetradecanoylphorbol-13-acetate, and KCl stimulate and forskolin potentiates insulin release. Mannoheptulose, 2-deoxyglucose, and nitrendipine inhibit glucose-stimulated insulin release from the cells. The intracellular Ca2+ concentration was raised by high glucose and by glibenclamide. In conclusion, this cell line preserves the fundamental characteristics of the progenitor normal mouse islets very well. Although several cell lines have been reported to have glucose-responsive insulin secretion, few demonstrate clear biphasic secretion as this cell line displays. In this context, this cell line should serve as a potent tool for studying the mechanisms of insulin secretion, especially the important phasic secretion.

Antioxidant property of Fructus Momordicae extract

The antioxidant effect of Fructus Momordicae extract, FME (mogrosides 75 approximately 80%), was studied. FME reduced the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and scavenged superoxide radicals (O2-) generated by a hypoxanthine and xanthine oxidase system. It also scavenged hydroxyl radicals (.OH) generated by Fenton reaction. In addition, FME inhibited Fe(II) induced lipid peroxidation in rat cortex homogenates in a dose-dependent manner, as indicated by decreased thiobarbituric acid-reactive substances (TBARS) formation. Oral administration of FME inhibited TBARS and malonaldehyde (MDA) formation in the ipsilateral cortex 30 min after iron-salt injection into the left cortex of rat. FME showed inhibitory effect on 4-hydroxy-2(E)-nonenal (4-HNE) formation induced by Fe(III) injection into the rat cortex. These data suggest that Fructus Momordicae extract has an antioxidant activity against free radicals and lipid peroxidation.

Technical note: use of a PCR-single strand conformation polymorphism (PCR-SSCP) for detection of a point mutation in the swine ryanodine receptor (RYR1) gene

We used the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis for screening the point mutation (C1843 to T) in the porcine ryanodine receptor (RYR1) gene. The PCR products (659 bp) were heat-denatured and separated by polyacrylamide gel electrophoresis. On silver-stained gels, the point mutation within the RYR1 gene could be detected clearly by mobility shifts. The best conditions for detecting the point mutation were by using a 5% polyacrylamide gel without glycerol and loading at 3 degrees C. The RYR1 genotypes diagnosed by PCR-SSCP were identical to the genotypes diagnosed by restriction enzyme fragment length polymorphism in all cases examined (n = 606).