Effects of dynorphin A-(1-13) on carbon monoxide-induced delayed amnesia in mice studied in a step-down type passive avoidance task

The effects of dynorphin A-(1-13) on carbon monoxide (CO)-induced amnesia in mice were investigated using a step-down type passive avoidance task. Memory deficiency occurred in mice when training commenced 7 days after CO exposure although it was not produced 1 day after CO exposure. The median step-down latency in the retention test of the CO-exposed group was significantly shorter than that of the control group. Administration of dynorphin A-(1-13) (1.5 nmol/mouse i.c.v.) 15 min before the first training session prolonged the step-down latency in the CO-exposed group. Dynorphin A-(1-13) administered immediately after the first training session or administered 15 min before the retention test also prolonged the step-down latency in the CO-exposed group. To determine whether this effect of dynorphin A-(1-13) was mediated via kappa-opioid receptors, we attempted to block its action using a kappa-opioid receptor antagonist (nor-binaltorphimine). Nor-binaltorphimine (5.44 nmol/mouse i.c.v.) blocked the effect of dynorphin A-(1-13) on delayed amnesia. However, dynorphin A-(1-13) (0.5, 1.5 and 5.0 nmol/mouse) did not facilitate the acquisition of memory in normal mice. These results suggest that dynorphin A-(1-13) modulates the kappa-opioid receptor-mediated opioid neuronal system, and that it ameliorates the disruptive effect of CO on acquisition, consolidation and/or recall of memory.

Isolation of Xenopus LMP-7 homologues. Striking allelic diversity and linkage to MHC

The mammalian low molecular mass protein-7 (LMP-7) gene resides in the class II region of the MHC, and its product is most probably involved, as a component of a proteasome, in the processing of Ags to be presented by the MHC class I molecules. To elucidate the evolution of the LMP-7 gene at both the primary structure and genetic levels, we isolated LMP-7 cDNA clones from amphibian Xenopus laevis, which last shared a common ancestor with mammals 350 x 10(6) years ago. Two distinctive clones, showing an 85% predicted amino acid sequence identity with each other and 69 to 72% identity with human and mouse LMP-7, were identified from a liver cDNA library of outbred frogs and named XeLMP-7A and XeLMP-7B. XeLMP-7A- and XeLMP-7B-specific probes were used to detect the corresponding genes by using partially inbred frogs with known MHC haplotypes. DNA of the g and j haplotypes hybridized with the XeLMP-7A probe, whereas the f and r haplotype DNA hybridized with the XeLMP-7B probe. These hybridization patterns cosegregated with the MHC haplotypes among offspring of an f/f x f/g cross, and one recombinant revealed that the LMP-7 gene is linked more closely to class II than to class I or class III genes. Taken together, the data indicate that XeLMP-7A and XeLMP-7B are highly diverse alleles at a single locus in the frog MHC. The great allelic diversity can be explained either by coselection with particular class I alleles or by differential silencing of MHC genes in the polyploid X. laevis.

Isolation of Xenopus LMP-7 homologues. Striking allelic diversity and linkage to MHC

The mammalian low molecular mass protein-7 (LMP-7) gene resides in the class II region of the MHC, and its product is most probably involved, as a component of a proteasome, in the processing of Ags to be presented by the MHC class I molecules. To elucidate the evolution of the LMP-7 gene at both the primary structure and genetic levels, we isolated LMP-7 cDNA clones from amphibian Xenopus laevis, which last shared a common ancestor with mammals 350 x 10(6) years ago. Two distinctive clones, showing an 85% predicted amino acid sequence identity with each other and 69 to 72% identity with human and mouse LMP-7, were identified from a liver cDNA library of outbred frogs and named XeLMP-7A and XeLMP-7B. XeLMP-7A- and XeLMP-7B-specific probes were used to detect the corresponding genes by using partially inbred frogs with known MHC haplotypes. DNA of the g and j haplotypes hybridized with the XeLMP-7A probe, whereas the f and r haplotype DNA hybridized with the XeLMP-7B probe. These hybridization patterns cosegregated with the MHC haplotypes among offspring of an f/f x f/g cross, and one recombinant revealed that the LMP-7 gene is linked more closely to class II than to class I or class III genes. Taken together, the data indicate that XeLMP-7A and XeLMP-7B are highly diverse alleles at a single locus in the frog MHC. The great allelic diversity can be explained either by coselection with particular class I alleles or by differential silencing of MHC genes in the polyploid X. laevis.

Coexistence of MEN 2A and papillary thyroid carcinoma and a recurrent pheochromocytoma 23 years after surgery: report of a case and a review of the Japanese literature

A 59-year-old woman who had undergone bilateral partial adrenalectomy 23 years previously was referred to our hospital because of neck masses and a left adrenal tumor. Fine needle aspiration biopsy of the neck tumor and elevated levels of calcitonin and CEA revealed medullary thyroid carcinoma. Slightly elevated levels of urinary normetanephrine and metanephrine, and results of a clonidine suppression test, CT, magnetic resonance imaging, and 131I-metaiodobenzylguanidine scintigraphy of the abdomen indicated that the left adrenal tumor was a recurrent pheochromocytoma in the residual adrenal gland. After total thyroidectomy, bilateral medullary thyroid carcinomas and papillary thyroid carcinoma were recognized pathologically. Although the coexistence of bilateral pheochromocytoma and medullary thyroid carcinoma is suggestive of multiple endocrine neoplasia (MEN), association of MEN type 2A (MEN 2A) with papillary thyroid carcinoma may have occurred incidentally. A retrospective analysis of 9 cases of pheochromocytoma associated with papillary thyroid carcinoma reported in the Japanese literature demonstrated a male-to-female ratio of 1:8, and an average patient age of 56.2 years. The present case indicates that association between pheochromocytoma and thyroid carcinoma may not always involve medullary thyroid carcinoma.

An outbreak of goose parvovirus infection in Japan

In a Muscovy duck breeding-growing farm in Aomori prefecture, most of ducklings hatched during spring in 1994 died within two-week-old. The mortality was nearly 100%. In most cases, birds died without clinical signs and some with leg weakness. By serological and virological tests, the outbreak was identified as a goose parvovirus infection. In pathological test, however, no typical manifestations of goose parvovirus infections (hepatitis and intranuclear inclusion bodies in hepatic cells) were detected.

Effect of losartan, an angiotensin II receptor antagonist, on response of cortisol and aldosterone to adrenocorticotrophic hormone

Many imidazole derivatives are shown to inhibit adrenal steroid biosynthesis. The present study was undertaken to examine an effect of another imidazole derivative, losartan (an angiotensin II receptor antagonist), on responses of cortisol and aldosterone to adrenocorticotrophic hormone (ACTH). Nine patients with essential hypertension were given placebo orally for 7 days and 50 mg of losartan for the next 9 days. Response of serum cortisol and plasma aldosterone to intramuscular ACTH injection were determined before and at the end of the treatment with losartan. Serum cortisol and plasma aldosterone significantly increased after ACTH injection in both periods of treatment (placebo and losartan). The increments in these parameters during treatment with losartan were not significantly different from those during treatment with placebo. These results suggest that the inhibitory effect of losartan on adrenal steroid biosynthesis is negligible.

Serosal balls detected immunocytochemically in peritoneal lavage obtained during surgery

Using the immunoperoxidase technique, we studied "serosal balls," which have features resembling those of cells from primary and metastatic tumors, and may thus complicate cytodiagnosis. Serosal balls were detected in 32 (18%) of 174 peritoneal washings. The balls consisted of oval clusters of cells in solid masses surrounded by flattened cells. The interior of the serosal balls was stained green with Papanicolaou method, showing the presence of homogeneous amorphous material, sometimes stained in a filamentous pattern. Almost all serosal balls were stained immunocytochemically for both keratin and vimentin. The interior was stained with antibodies against collagen types I and III. Therefore, these balls were fragments of serous membrane, and contained fibrous tissue and mesothelial cells.

Simultaneous determinations of histamine and N tau-methylhistamine by high-performance liquid chromatography-chemiluminescence coupled with immobilized diamine oxidase

A method for the simultaneous determinations of histamine and its metabolite N tau-methylhistamine by HPLC-chemiluminescence coupled with immobilized diamine oxidase was developed. The method was based on the determination of chemiluminescence formed by the reaction of a luminol-ferricyanide mixture in alkaline medium with hydrogen peroxide which is one of the metabolic products of histamine and N tau-methylhistamine formed by diamine oxidase. HPLC with postcolumn derivatization resulted in good separation of the two amines and gave linear relationships between the concentrations of both and their chemiluminescence intensities. The lower limits of chemiluminescent detection of histamine and N tau-methylhistamine were 5 and 10 pmol, respectively. The immobilized column showed good operational stability for more than 1 month, during which period 200 samples were analyzed. With this system, the histamine contents of the cerebral cortex, forestomach, glandular stomach, and kidney of Wistar rats were found to be 0.30, 58, 396, and 2.4 nmol/g wet wt, respectively. These values are very similar to those determined by HPLC-fluorometry. The N tau-methylhistamine contents of these tissues were 0.36, 0.40, 0.72, and 3.8 nmol/g wet wt, respectively. This method will be useful for studying the roles of histamine in both brain and peripheral tissues.

[A case report of primary pulmonary artery sarcoma]

A 49-year-old man was admitted because of dyspnea and generalized edema. CT scan pulmonary scintigram and cardiac catheter examination revealed pulmonary arterial obstruction due to a tumor associated with right heart failure. The tumor was extirpated as much as possible by a pulmonary arteriotomy under cardiopulmonary bypass. Postoperatively, right ventricular pressure decreased to about 40 mmHg while PO2 increased to the normal level. Histological examination of the tumor revealed rhabdomyosarcoma arising from the pulmonary artery. Chemotherapy consisting of a single course of CDDP and adriamycin was administered.

Duplication of the MHC-linked Xenopus complement factor B gene

We have previously reported the molecular cloning of the mammalian major histocompatibility complex (MHC) class III gene, complement factor B (Bf) from Xenopus laevis, and linkage of the gene to the frog MHC. Here, we estimated the copy number of the Xenopus Bf gene by genomic Southern blotting analysis and demonstrated that Xenopus laevis has two copies of the Bf gene. Both genes co-segregated with the MHC-linked HSP70 genes among 19 offspring of an f/r x f/r cross, indicating a close linkage of the two Bf genes to the frog MHC. Both genes are transcribed and contain open reading frames. When compared with the previously determined cDNA sequence (Xenopus Bf A), the predicted amino acid sequence of the second cDNA species (Xenopus Bf B) shows 82% overall identity. Polymerase chain reaction analysis indicated that all of the partially inbred frogs with the f, r, g, and j MHC haplotypes, as well as 12 outbred frogs tested have both Bf genes, suggesting that the duplicated Bf genes are stable genetic traits in Xenopus laevis.

Transesophageal echocardiographic evaluation of mitral regurgitation in hypertrophic cardiomyopathy: contributions of eccentric left ventricular hypertrophy and related abnormalities of the mitral complex

This study was designed to evaluate the contribution of eccentric left ventricular hypertrophy and its related organic and spatial abnormalities of the mitral complex to the occurrence of mitral regurgitation in patients with hypertrophic cardiomyopathy We selected 45 consecutive patients with systolic mitral regurgitation by color Doppler echocardiography and performed transesophageal echocardiography in all patients. Eighteen patients were in the obstructive group and 27 patients were in the nonobstructive group of hypertrophic cardiomyopathy with asymmetric septal hypertrophy. Twenty subjects without any cardiac disorders served as the control group. The maximum area of mitral regurgitation was significantly greater in the obstructive group than in the nonobstructive group. Mitral regurgitation appeared more frequently during pansystole in the two groups with hypertrophic cardiomyopathy, particularly in the obstructive group. Mitral valve prolapse was observed in 20 (44%) of the 45 patients with hypertrophic cardiomyopathy. Distances between the posterior papillary muscle and anterior or posterior mitral anulus were significantly smaller in the two groups with hypertrophic cardiomyopathy than in the normal control group. In the obstructive group, the length of the anterior mitral leaflet and the thickness of the rough zone of the anterior mitral leaflet at mid-diastole were significantly greater than in the other groups. Systolic anterior motion was observed in all patients with obstructive cardiomyopathy and contact between the interventricular septum and the anterior mitral leaflet during early diastole was observed in 17 of the 18 patients in the obstructive group.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic criteria in patients with stage D2 prostate cancer. Correlation with mean nuclear volume

BACKGROUND

Histologic grading, especially the Gleason score (GS), is considered to be of value in determining the prognosis of patients with prostate cancer. However, subjective histologic grading is characterized by low reproducibility. Conversely, estimates of mean nuclear volume (MNV), developed by Gunderson and Jensen based on a stereologic technique, is a method with high reproducibility. Furthermore, it has been reported that MNV provides an accurate prognosis of bladder cancer. In this study MNV was compared with two histologic grading methods in determining the prognosis of Stage D2 prostate cancer.

METHODS

A retrospective, prognostic study of 31 patients with Stage D2 prostate cancer treated with transurethral resection of the prostate or needle biopsy between January, 1983, and July, 1994, was performed. Unbiased estimates of MNV were compared with age at the time of diagnosis, histologic grading according to World Health Organization (WHO) classification, and GS on the prognostic value.

RESULTS

Age at the time of diagnosis, WHO classification and GS had no value as prognostic criteria, and only MNV correlated significantly with prognosis of Stage D2 prostate cancer (P = 0.0017).

CONCLUSION

Results of this study indicate that MNV is prognostically superior to morphologic grading of malignancy, such as GS and WHO classification, in Stage D2 prostate cancer.

Hepatocellular prolapse of hepatic portal tracts and subendothelial space of central veins in idiopathic portal hypertension

We report a case of idiopathic portal hypertension (IPH) with unusual liver pathology. The liver showed changes similar to these previously reported in IPH and, in addition, we observed the unusual features of prolapse of hepatocytes into portal tracts and also into the subendothelial space of hepatic veins. Hepatocyte prolapse into hepatic veins has previously been reported only in patients with a history of androgenic steroid therapy and immunosuppressive therapy. We speculate that, in our case, prolapse of hepatocytes could be related to the abnormal intrahepatic blood flow or to intrahepatic vasculopathy.

Pulmonary and systemic venous flow patterns assessed by transesophageal Doppler echocardiography in congenital absence of the pericardium

In conclusion, alterations in venous return are more marked in the right side of the heart than in the left side of the heart in patients with complete absence of the left pericardium.

Recurrence of osteogenesis imperfecta because of paternal mosaicism: Gly862-->Ser substitution in a type I collagen gene (COL1A1)

We determined that two siblings with type III osteogenesis imperfecta (OI) had the same single base substitution that converted the codon for glycine (Gly) 862 to a codon for serine (Ser) in exon 44 of the alpha 1 chain of the type I (alpha 1(I)) collagen gene (COL1A1). The mutation was also detected in various paternal tissues; the mutant allele accounted for approximately 11% of the COL1A1 alleles in blood, 24% of those in fibroblasts, and 43% of those in sperm determined by allele-specific colony hybridization using amplified genomic sequences. These findings demonstrate that germ-line mosaicism in the phenotypically normal father is responsible for the recurrence. There is a cluster of serine substitutions for Gly (Gly832, Gly844 and Gly901) which is associated with nonlethal phenotypes and which is located between two lethal clusters. In the cases studied here, a Gly862-->Ser mutation was identified that is located inside the nonlethal cluster.

[A comparison of the cerebrovascular responses to CO2 and Diamox in patients with unilateral occlusive cerebral arteries: a H2(15)O PET study]

We studied the relationship between the cerebrovascular responses to CO2 and Diamox in patients with chronic cerebrovascular diseases. The subjects consisted of 11 patients with unilateral occlusive or highly stenotic carotid artery. The cerebral blood flow was measured at the resting state, during the inhalation of 5% CO2, at both 5 and 20 min after Diamox i.v. (1 g). The rCBF ratios (occlusive/non-occlusive side) during the inhalation of CO2 and 20 min after Diamox i.v. closely correlated with each other. However, the ratio at 5 min after Diamox i.v. was slightly lower than that during the inhalation of CO2. The percent increases of rCBF also showed a significant correlation between 5% CO2 inhalation and 20 min after Diamox i.v. However, the rCBF decreased inversely at 5 min after Diamox i.v. in some regions on the occlusive side, which indicates the presence of a so-called "steal phenomenon". The percent increases in the rCBF after 1 g Diamox i.v. were more or equal to those during the inhalation of 5% CO2. The CO2 and Diamox were thus considered to be equally useful in the evaluation of the perfusion reserve capacity. However, these various characteristics as described above should be considered in the clinical practice.

Effect of feeding clofibrate-containing diet on the hepatic NAD+ level in rats

Feeding rats with a diet containing 0.25% clofibrate for 2 weeks elevated the hepatic NAD+ and total nicotinate levels significantly. Other peroxisome proliferators, such as 2-(4-chlorophenoxy)propionic acid and di(2-ethylhexyl)phthalate, had similar effects. When rats were fed the control diet without clofibrate for 1 week after 2 weeks of the clofibrate diet, the hepatic NAD+ level returned to the control value. Muscular NAD+ content was not affected by the peroxisome proliferators. The results were discussed in relation to induction of peroxisomal beta-oxidation enzymes by the peroxisome proliferators.

Calcium requirement and inhibitor spectrum for intracellular HIV type 1 gp160 processing in cultured HeLa cells and CD4+ lymphocytes: similarity to those of viral envelope glycoprotein maturase

We recently purified the calcium-independent processing protease named viral envelope glycoprotein maturase (VEM), that converts human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein precursor gp160 to gp120 and gp41, from the human CD4+ T cell line, Molt-4 clone 8 [Kido, H., Kamoshita, K., Fukutomi, A., and Katunuma, N. (1993) J. Biol. Chem. 268, 13406-13413]. In this report, we deal with the inhibitor specificity and calcium requirement for intracellular gp160 processing in cultured HeLa cells and human CD4+ lymphocytes. Processing of gp160 in these cells infected with recombinant vaccinia virus encoding the gp160 gene was not affected by intracellular calcium depletion induced by the calcium ionophore A23187 and EGTA or by intracellular calcium administration. Processing of gp160 by the purified VEM in vitro was not inhibited by EDTA, EGTA, or the metallo-protease inhibitor phosphoramidon, but was specifically inhibited by a substrate analog, decanoyl-RVKR-chloromethylketone, and the trypsin-type protease inhibitors aprotinin, HI-30, and diisopropyl fluorophosphate (DFP). It was also inhibited by E-64 and thiol reagents. But intracellular gp160 processing was inhibited only by permeable, low molecular mass inhibitors of VEM, such as DFP, E-64, and thiol reagents. Syncytium formation induced by cell surface gp120 was also inhibited by permeable inhibitors of VEM. Taken together, our results indicate that calcium ions may not be essential for intracellular gp160 processing and so HIV-1 gp160 induced by recombinant vaccinia virus may be processed mainly by a protease(s) that does not require calcium ions, such as VEM in these cells.

Serum concentrations of granulocyte colony-stimulating factor (G-CSF) determined by a highly-sensitive chemiluminescent immunoassay during the clinical course of subacute thyroiditis

Granulocyte colony-stimulating factor (G-CSF) concentrations in serum were determined for the first time by a newly developed and highly sensitive chemiluminescent immunoassay (the limitation of detection, 0.5 pg/ml) in ten patients with subacute thyroiditis, during treatment with glucocorticoid or indomethacin. Before therapy, circulating neurophil counts significantly increased to 5.15 +/- 2.07 x 10(3)/microliters compared with the convalescent phase (2.94 +/- 1.07 x 10(3)/microliters), and the data were correlated with individual serum G-CSF levels (r = 0.854, P < 0.01). Serum concentrations of interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were less than the detectable threshold of ELISA. During two weeks of glucocorticoid therapy, although the circulating neutrophil counts increased from 5.15 +/- 2.46 x 10(3)/microliters to 7.73 +/- 1.64 x 10(3)/microliters (P < 0.01), serum G-CSF levels were depressed from 25.1 +/- 15.3 pg/ml to 13.8 +/- 13.9 pg/ml (P < 0.01). These data indicate that G-CSF is one of the mediators of the increase of neutrophils in subacute thyroiditis, while it does not contribute to steroid-induced neutrophilia.

Putative mechanism for guinea pig ileum contraction by N-formyl peptides. A comparative study of N-formyl and N-acetyl peptides with the N-terminal sequence of the calpain small subunit

N-formyl and N-acetyl peptides with the N-terminal sequence of the calpain small subunit were prepared and their spasmogenic activity was examined using guinea pig ileum preparations. Sections of ileum were found to contract in the presence of all N-formyl peptides used (tri- to nonapeptides and tridecapeptide) but failed to contract with N-acetyl peptides, although both N-formyl and N-acetyl peptides have chemotactic activity, indicating that spasmogenic activity and chemotactic activity involve different mechanisms. A formyl peptide antagonist, Boc-Phe-Leu-Phe-Leu-Phe, suppressed contraction by formyl peptides whereas a histamine antagonist, diphenhydramine, suppressed contraction by formyl peptides as well as by histamine. In addition, formyl peptide-induced contractions were noted after an approximately 20-sec time lag, and their profiles were bell-shaped and roughly symmetrical. On the other hand, histamine- and acetylcholine-induced contractions exhibited a much shorter time lag. These data led us to conclude that contraction induced by formyl peptides may not occur as a direct response but may be due to the histamine released from mast cells present in the tissues of the small intestine.

[Changes in pulmonary venous and transmitral flow velocity patterns after cardioversion of atrial fibrillation]

The time course of recovery of left atrial mechanical function after electrocardioversion of atrial fibrillation was examined in 25 patients with atrial fibrillation by recording pulmonary venous and transmitral flow velocities and interatrial septal motion during atrial systole within a day (16 +/- 5 hours) and ten days after cardioversion of atrial fibrillation by transesophageal and transthoracic Doppler and M-mode echocardiography. There were 6 patients with hypertension, 4 with ischemic heart disease, 2 with alcoholic heart, 5 with dilated cardiomyopathy, and 8 without underlying heart disease. The peak velocities of the atrial systolic waves of the transmitral and pulmonary venous flow velocities (A and PVA, respectively) and first systolic wave (PVS1) of pulmonary venous flow, durations of both atrial systolic waves, and amplitude of interatrial septal motion during atrial systole increased significantly ten days after cardioversion compared with those measured within a day of cardioversion in all patients except the 5 patients with dilated cardiomyopathy. Peak velocity of the second systolic wave (PVS2) of pulmonary venous flow increased, and that of the early diastolic and diastolic waves (E and PVD, respectively) of transmitral and pulmonary venous flow decreased ten days after cardioversion compared with those within a day of cardioversion. These results suggested that active atrial systolic (A and PVA) and relaxant (PVS1) parameters obtained from transmitral and pulmonary venous flow velocities are good indicators of left atrial mechanical function after cardioversion of atrial fibrillation.