Conditioned taste aversion in rats with excitotoxic brain lesions

Conditioned taste aversion (CTA) is well known to be a robust and long-lasting learning after a single conditioned stimulus (CS) (taste)--unconditioned stimulus (US) (malaise) pairing. The neural mechanisms of this taste aversion learning still remain to be resolved. To elucidate the basic brain mechanisms of the taste aversion learning, we examined the effects of lesions of various sites of the rat brain on the acquisition and retention of CTAs. Confined brain lesions were made by injections of a small amount of excitotoxic drug, ibotenic acid. CTAs were established to saccharin (CS) by pairing its ingestion with an i.p. injection of LiCl (US). Rats lacking the parabrachial nucleus (PBN) almost completely failed to acquire CTAs. The second most effective lesion was in the medial thalamus including the parvocellular part of the ventral posteromedial nucleus of the thalamus (VPMpc) and the midline part, followed by the damage of the lateral nuclear group of the amygdala including the basolateral amygdaloid nucleus. Lesions of the gustatory cortex (GC) and hippocampus induced moderate effects, but lesions in the other subnuclei of the amygdala, such as the medial and central amygdaloid nuclei, entorhinal cortex, lateral hypothalamic area, and ventromedial hypothalamic nucleus induced slight or no effects. On the other hand, paired lesions among the amygdala, medial thalamus and GC caused severe impairment of CTAs; in particular, lesions of amygdala and VPMpc completely disrupted acquisition of CTAs. These results suggest that the PBN, medial thalamus and the lateral nuclear group of the amygdala play an essential role in the formation of taste aversion learning.

Endometrial oestrogen and progesterone receptors and their relationship to sonographic endometrial appearance

The present study was undertaken to evaluate a possible relationship between the endometrial concentrations of oestrogen receptor (ER) or progesterone receptor (PR), and the sonographic appearance of human endometrium. Sonographic assessments and aspirations of the endometrium at the time of or prior to ovulation were made in 48 cycles of 45 infertile women. Endometrial patterns were classified as A, triple line pattern, or B, not triple line, on the basis of echogenicity. We did not find a correlation between ER or PR and serum oestradiol or endometrial thickness. Furthermore, serum oestradiol concentrations were not correlated with endometrial pattern or thickness. The only significant correlations were found between the concentrations of ER and PR in the pattern A endometrium (r = 0.80, P < 0.01) and in the pattern B endometrium (r = 0.49, P < 0.05). There were no differences in the mean concentrations of ER and PR despite differences in endometrial pattern and thickness. However, PR was measured at > 800 fmol/mg protein in 12 out of 38 pattern A endometria, while PR was < 800 fmol/mg protein in all pattern B endometria. These data suggest that high PR expression in the pre-ovulatory period is related to an adequate endometrial growth and thereby increases the responsiveness of the endometrium to progesterone stimulation after ovulation.

[A case of Sjögren's syndrome with rheumatoid arthritis manifesting transverse myelitis with antineuronal antibody]

We report a sixty-year-old woman with transverse myelitis who had suffered from rheumatoid arthritis since age of 52. She was admitted to our department because of muscle weakness and painful tonic spasm in the bilateral lower extremities, sensory disturbance below the mamillary level and bladder disturbance. She had sicca symptoms. As a result of sialography, Sjögren's syndrome was diagnosed. Antineuronal antibody was found in the sera of the patient. She had no symptom of systemic vasculitis. Lupus anticoagulant and anticaldiolipin antibody were negative. The pathogenesis of transverse myelitis in rheumatic disease is still uncertain. Vasculitis and the immunological reaction of antineuronal antibody have been suggested as possible causes. This report suggests the influence of direct immunological reaction on the central nervous system.

A case of primary Hodgkin's disease of the stomach

A case of primary Hodgkin's disease, a lymphocyte-predominant entity, occurring in the stomach is described. The patient was a 37-year-old man who complained of general fatigue. Endoscopic biopsy revealed gastric malignant lymphoma. Subtotal gastrectomy and postoperative chemotherapy following a modified CHOP regimen were performed. The patient has been free of recurrence during a follow-up period of 15 months. The preoperative diagnosis of gastric Hodgkin's disease is difficult. Thus far, of 100 cases of gastric Hodgkin's disease reported in Japan, only 3 were diagnosed correctly preoperatively. We also misdiagnosed our case, as B cell type malignant lymphoma, preoperatively. The final diagnosis of Hodgkin's disease of the stomach was made on the basis of histopathological and immunohistochemical examinations. Hodgkin's disease of the stomach is rare, and there are histologically similar diseases; Ki-1 lymphoma, adult T cell lymphoma, malignant histiocytosis, and infectious monocytosis. Careful diagnosis is essential thus for Hodgkin's disease of the stomach.

Myxoma of the maxilla

A case of myxoma, arising in the maxilla of a 28-year-old female, is presented. Relevant literature is discussed.

Inhibition of 15-hydroxy prostaglandin dehydrogenase activity in rabbit gastric antral mucosa by 13-hydroperoxyoctadecadienoic acid

The effect of 13-hydroperoxyoctadecadienoic acid (13-HPODE), a hydroperoxy adduct of linoleic acid (LA), on the activities of prostaglandin (PG) synthesizing and catabolizing enzymes in rabbit gastric antral mucosa was examined. 13-HPODE had no effect on the synthesis of PGE2, PGF2 alpha and PGD2 from exogenous arachidonic acid in the microsomal fraction of the gastric mucosa at concentrations ranging from 5-20 microM. On the other hand, at 1-10 microM, it inhibited the activity of 15-hydroxy PG dehydrogenase (PGDH), which catalyzes the initial step of catabolism of PGs, in a dose-dependent manner. The concentration required for 50% inhibition was approximately 1 microM. Experiments utilizing LA, 13-hydroperoxyoctadecadienoic acid and Fe2+ indicated the requirement of the hydroperoxy moiety for the inhibitory effect of 13-HPODE on the PGDH activity. These results suggest that 13-HPODE has the potential to increase the levels of biologically active PGs in gastric mucosa by preventing their inactivation and may have functional effects within the stomach.

[A rare case of high cervical spinal cord dural arteriovenous fistula presenting with intracranial subarachnoid hemorrhage]

It is now recognized that spinal dural arteriovenous fistula causes myelopathy, resulting from congestive venous hypertension of the spinal cord. We have recently encountered a rare case of high cervical spinal cord dural arteriovenous fistula which caused intracranial subarachnoid hemorrhage. The patient was a 62-year-old female, who had exhibited an abrupt onset of severe headache and loss of consciousness. Plain head CT scan revealed intracranial subarachnoid hemorrhage. No abnormal vascular lesions were found on the first cerebral angiography. The second angiographical examination demonstrated a spinal arteriovenous malformation at the high cervical region. A dural arteriovenous fistula around the right C2 nerve root was found by surgical intervention. The fistula was recognized between rt. C2 radicular artery and dural sheath of rt. C2 nerve root, draining to the epidural plexus and intradural local medullary vein. No serpentine coronal venous plexus on the dorsal aspect of the cervical cord was seen as it is in a usual dural type of spinal arteriovenous fistula. The bleeding point was an intradural varix of the medullary vein just where it penetrated the nerve root area. Feeder ligation of the C2 radicular artery and coating of the varix complex were performed. The postoperative course was uneventful. The patient was discharged from our institute with no neurological deficits.

Nonkallikrein arginine endopeptidase in the human submaxillary gland: purification and characterization of the enzyme

The two major species of arginine endopeptidase present in the soluble fraction of human submaxillary gland are glandular kallikrein and another enzyme tentatively named nonkallikrein arginine endopeptidase. In this study, we purified the latter enzyme to homogeneity and examined its catalytic properties. The newly found enzyme was clearly distinguishable from human tissue kallikrein in its molecular nature, action toward various synthetic substrates, and kinin-generated activity. The specificity of the action of the enzyme was further investigated using various basic amino acid-containing peptides as model substrates. HPLC analysis of peptide fragments produced, followed by their amino acid analysis, revealed that the enzyme preferentially hydrolyzed the Arg-Arg or Arg-Lys bonds in dynorphins A 1-10, 1-9, and 1-8, beta-neoendorphin, adenorphin, and neurotensin.

[A study on predicting factors of the effect of intra-arterial infusion chemotherapy in patients with bladder cancers: the usefulness of in-vitro chemisensitivity test measuring intracellular ATP contents (ATP assay)]

We studied a relationship between in vitro sensitivity of the tumors to anti-cancerous drugs and histopathological effectiveness of an intra-arterial infusion chemotherapy in 15 patients with bladder cancers. The in vitro sensitivity test was performed by measuring intra-cellular ATP contents (ATP assay). The intra-arterial chemotherapy were performed by injecting methotrexate (MTX), adriamycin (ADM) and eisplatin (CDDP) from the internal iliac artery. When the intra-cellular ATP contents of the tumor cells treated with an anti-cancerous drug decreased to less than 50% of the untreated tumor cells, the tumor was evaluated as sensitive to the drug. The effectiveness of the chemotherapy were histopathologically evaluated by a pathologist according to the response criteria for bladder cancer treatment. When the histopathological responses of higher than grade 2 were observed in the tumor, the chemotherapy was evaluated as effective. In 8 of 9 tumors sensitive to ADM, chemotherapy were effective histopathologically and in all 6 tumors resistant to ADM, histopathological response of the chemotherapies were poor. The overall coincidence ratio between sensitivity to ADM and the histopathological effectiveness of the chemotherapy was 93%, showing statistically significant correlation. In 7 of 12 tumors sensitive to CDDP, the chemotherapies were effective and in 2 of 3 tumors resistant to CDDP, the chemotherapies were ineffective. Although the overall coincidence ratio between the sensitivities to CDDP and chemotherapeutic effectiveness was 60%, there was no significant correlation between them. In 7 of 8 tumors sensitive to both of ADM and CDDP, the chemotherapies were effective and in 6 of 7 tumors resistant to at least one of them, the chemotherapies were ineffective. (ABSTRACT TRUNCATED AT 250 WORDS)

[Aberrations of tumor suppressor genes in hepatocellular carcinomas]

Mutation of the p53 gene and loss of heterozygosity of the p53, Rb, APC, and MCC genes were examined in 14 hepatocellular carcinomas (HCCs) diagnosed at the third department of internal medicine in Asahikawa Medical College. Mutations in the p53 gene were detected in 4 HCCs out of 14 (25%) using polymerase chain reaction-single strand conformational polymorphism. The sites of the mutations showed a random distribution from exon 6 to 8. No mutation was observed at codon 249, which has been considered as a mutational hot spot caused by aflatoxin B1. All of the mutations occurred at a G:C base pair site, while two mutations were C:G to T:A transitions and other two mutations were G:C to T:A transversions. Pathological examination showed that the 14 HCCs consisted of 7 moderately and 7 poorly differentiated HCCs. All of the 4 HCCs which showed mutations were poorly differentiated and the frequency of the mutations were 0% in moderately and 57% in poorly differentiated HCCs. Loss of heterozygosity of the p53, Rb and APC genes were examined in the 14 HCCs using restriction fragment length polymorphism analysis. Frequencies of the loss of the p53, Rb, APC, and MCC genes were 2 out of 7 informative cases (2/7), 1/6, 0/4, and 0/7, respectively. Frequency of loss of the p53 gene in four HCCs carrying a mutated p53 gene was 1/3. These data suggest that inactivation of the p53 gene is involved in human hepatocarcinogenesis, but the APC/MCC genes are not.

High density lipoprotein inhibits platelet 12-lipoxygenase activity

The effects of high density lipoprotein (HDL) and low density lipoprotein (LDL) on the formation of 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE), thromboxane (TX) B2 and 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) in washed rabbit platelets were examined. HDL had a powerful inhibitory effect on 12-HETE formation, while it produced only a small increase in TXB2 and HHT formation. LDL did not affect the formation of 12-HETE, TXB2 and HHT. These results suggest that HDL is a selective inhibitor of platelet 12-lipoxygenase and may play a protective role in atherogenesis by preventing the generation of 12-HETE.

Total syntheses of (2S)-antafumicins A and B

To clarify the absolute configurations of antafumicins A and B, which are antifungal substances from Aspergillus niger NH-401, the total synthesis of (2S)-antafumicins was accomplished by starting from (S)-malic acid in 12 steps. Based upon the physicochemical data of the synthetic samples, the absolute configurations of naturally occurring antafumicins A and B were determined as (2R,4S)- and (2R,4R)-4-(3-acetyl-2,6-dihydroxyphenyl)-2-methoxy-4-butanolide, respectively.

Existence of an enzymatic pathway furnishing arachidonic acid for prostaglandin synthesis from arachidonoyl CoA in rabbit kidney medulla

We examined whether arachidonoyl CoA (AA-CoA) can be a possible supplier of arachidonic acid (AA) for prostaglandin (PG) synthesis in rabbit kidney medulla. AA-CoA was preincubated with or without the 105,000 g supernatant (cytosol) fraction from the kidney medulla for 5 min at 37 degrees C followed by the incubation with the microsomal fraction (0.5 mg protein) (a rich source of PG synthesizing enzymes) in the presence of reduced glutathione and hydroquinone for 5 min at 37 degrees C, and the formed PGE2, F2 alpha and D2 were measured by high-pressure liquid chromatography using 9-anthryldiazomethane for derivatization. The addition of AA-CoA (20 nmol) alone changed the total PG formation (the sum of PGE2, F2 alpha and D2) from 0.14 to 1.55 ng. When the cytosolic fraction (10-100 microliters) was added together with 20 nmol-AA-CoA in the preincubation mixture, total PG formation was further increased 2- to 3-fold compared to AA-CoA alone. Experiments utilizing AA, instead of AA-CoA and boiled cytosolic fraction revealed that the stimulatory action of the cytosolic fraction on the AA-CoA-induced PG synthesis may not be due to the effect on cyclooxygenase activity and due to long-chain acyl CoA hydrolase. These results show that long-chain acyl CoA hydrolase which hydrolyzes AA-CoA to AA is present in the cytosol of rabbit kidney medulla and suggest that this enzyme activity is a potential mediator of supply of AA for PG synthesis in this region.

Structure-specific inhibition of lysosomal cholesterol transport in macrophages by various steroids

Cultured mouse peritoneal macrophages effectively take up and metabolize liposomes containing phosphatidylserine and cholesterol, resulting in massive accumulation of cholesteryl esters and triacylglycerols in their cytoplasm (Nishikawa, K., Arai, H. and Inoue, K. (1990) J. Biol. Chem. 265, 5226-5231). With this system, various steroid derivatives were assessed as to their ability to inhibit the cholesteryl ester formation from endocytosed cholesterol in macrophages. Among the steroids tested, one group of steroids having an oxo group at the C17 or C20 position, such as androstenedione, dehydroisoandrosterone, progesterone and pregnenolone, completely inhibited cholesteryl ester formation at 10 microM. Another group of steroids having a hydroxy group at the C17 position, such as testosterone and androstenediol, had a lesser effect; complete inhibition of cholesteryl ester formation was achieved with 100 microM or more. The mechanism underlying the inhibition by the former class of steroids was further studied. These steroids did not block the uptake or lysosomal hydrolysis of liposomes, nor esterification of fatty acyl chains into triacylglycerols. Moreover, dehydroisoandrosterone and pregnenolone, both of which possess a hydroxy group at the C3 position, had essentially no effect on 25-hydroxycholesterol-stimulated esterification of endogenous cellular cholesterol. On the other hand, androstenedione and progesterone, which possess an oxo group at the C3 position, had a mild inhibitory effect on the esterification of endogenous cholesterol. Upon incubation with a steroid having an oxo group at the C17 or C20 position, free cholesterol taken up by macrophages was accumulated in phagolysosomes, as judged from cytochemical study with filipin-cholesterol staining. These results indicate that a series of structurally-related steroids characterized by the presence of an oxo group at the C17 or C20 position inhibit cholesteryl ester formation in macrophages through blocking the intracellular transport of endocytosed cholesterol from lysosomes to endoplasmic reticulum.

Importance of cytotoxic T lymphocytes in the rejection of transplanted hepatocellular carcinoma

Fischer rats became resistant to syngeneic hepatocellular carcinoma (FAA-HTC1) cells on repeated sensitization with mitomycin C-treated FAA-HTC1 cells. In contrast, FAA-HTC1 cells injected into the liver killed normal control Fischer rats within 2 months. Histopathological studies revealed massive accumulation of mononuclear cells in the tumor tissues of sensitized rats that rejected syngeneic FAA-HTC1 cells, whereas very few mononuclear cells were found in the tumor tissues of control rats. Cell populations infiltrating the tumor tissues were identified by flow cytometric analysis. Mononuclear cells found within the regressing tumors of the sensitized rats were identified as mostly T cells, and two-thirds of these T cells were CD8-positive. Compared with the activity in control rats, the killer activity of mononuclear cells infiltrating tumors was significantly increased in the sensitized rats 7 days after tumor inoculation. Depletion of CD8(+) T cells significantly reduced the cytotoxicity of mononuclear cells infiltrating tumors obtained from sensitized rats. In contrast, depletion of CD16(+) cells reduced the cytotoxicity of mononuclear cells infiltrating tumors obtained from both control and sensitized rats. Furthermore, the CD16(+) cell-depleted fraction of mononuclear cells infiltrating tumors showed significant cytotoxicity against FAA-HTC1 cells, but failed to show cytotoxicity against other syngeneic tumor cells or allogeneic hepatoma cells.

Induction of the conversion of xanthine dehydrogenase to oxidase in rabbit liver by Cu2+,Zn2+ and selenium ions

Effects of Cu2+,Zn2+,Fe2+ and selenium ions on the conversion of xanthine dehydrogenase to oxidase in rabbit liver were examined. Under basal conditions, xanthine oxidase activity represented only 16% of the total xanthine oxidase plus dehydrogenase activity. Cu2+ (2-10 microM), Zn2+ (5-30 microM) and selenium ions (5-100 microM) brought about the conversion of xanthine dehydrogenase to oxidase in a dose-dependent manner. The concentrations of Cu2+,Zn2+ and selenium ions required for increasing xanthine oxidase activity by 50% was approximately 4, 10 and 20 microM, respectively. On the other hand, Fe2+ had no effect on the conversion of the enzyme up to 100 microM. These results suggest that Cu2+,Zn2+ and selenium ions have the potential to modulate the conversion of xanthine dehydrogenase to oxidase in rabbit liver.

Test performances of three diagnostic procedures in evaluating thyroid nodules: physical examination, ultrasonography and fine needle aspiration cytology

A retrospective study was performed to determine the reliability of physical examination (PE), ultrasonography (US) and fine-needle aspiration cytology (FNA) in the evaluation of thyroid nodules. Preoperative diagnoses of 252 euthyroid patients comprised 126 with benign lesions, 114 with papillary carcinoma and 12 with follicular carcinoma made by PE, US and FNA were reviewed. The specificity of PE, US and FNA for malignancy was 98%, 90% and 98%, respectively. The sensitivity of PE, US and FNA for malignancy was 63%, 78% and 80%. The sensitivity for papillary carcinoma of the three procedures was 68%, 83%, 88%, whereas that for follicular carcinoma was 25%, 25%, 8%, respectively. When all the test results were negative, the likelihood ratio favoring papillary carcinoma was 0.008 whereas that favoring follicular carcinoma was 0.6. The histological category of carcinoma should be considered when evaluating diagnostic procedures for thyroid nodules. No negative test result is conclusive for ruling out the possibility of follicular carcinoma.

Dietary NaCl restriction deteriorates oral glucose tolerance in hypertensive patients with impairment of glucose tolerance

This study investigated whether the change of glycemic response to oral glucose loading with an increase of dietary NaCl intake is different between salt-sensitive and salt-resistant groups, or whether it is related to glucose tolerance on a low NaCl diet independent of salt sensitivity. The plasma glucose and insulin response to 75 g oral glucose intake was assessed on low (34 mmol/day) and high (342 mmol/day) NaCl diets in 31 patients with essential hypertension, and the area under the curve for both variables (AUCglu and AUCins) was calculated. The data on the high NaCl diet were corrected for change in hematocrit. The percentage change in systolic, diastolic, and mean blood pressure between the two diets was defined as the salt sensitivity index (SSI) for systolic blood pressure (SSISBP), diastolic blood pressure (SSIDBP), and mean blood pressure (SSIMBP), respectively. The mean values of both AUCglu and AUCins decreased significantly with increase of NaCl intake; however, there was no significant correlation between SSI (SSISBP, SSIDBP, or SSIMBP) and the percentage changes in AUCglu and AUCins. Meanwhile, the percentage changes in AUCglu and AUCins significantly correlated with the respective values of AUCglu and AUCins on the low NaCl diet. These results suggest that extreme NaCl restriction may deteriorate glucose metabolism in hypertensive patients, especially in those with diabetes mellitus or impaired glucose tolerance.

Sex pheromones in marine polychaetes: steroids from ripe Nereis succinea

A number of neutral marine steroids such as desmosterol, campesterol, brassicasterol, gorgosterol, and other trace steroids were isolated from the coelomic fluid of ripe Nereis succinea and checked for biological activity as sex pheromones on swarming specimens of Platynereis dumerilii and Nereis succinea. No significant influence of synthetic gorgosterol or a natural extract of gorgosterol or the other identified steroids on the swarming behavior was observed.

p53 gene mutation in hepatocellular carcinoma induced by 2-amino-3-methylimidazo[4,5-f]quinoline in nonhuman primates

2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) is one of several heterocyclic amines formed during the cooking of proteinaceous foods. IQ is a potent carcinogen in rodent bioassays and causes a high incidence of hepatocellular carcinomas in nonhuman primates. We examined 20 hepatocellular carcinomas (HCCs) from nonhuman primates for mutations of the p53 gene using polymerase chain reaction-single strand conformational polymorphism analysis. Mutations in the p53 gene were detected in 4 of 20 HCCs (20%) with 3 showing G-to-T transversions and one a G-to-A transition. Three of these mutations were observed in codons 175 and 248 that are known mutational hot spots in human cancers. These data indicate that part of the IQ-induced HCCs in nonhuman primates may involve inactivation of the p53 gene and suggest that IQ and possibly other heterocyclic amines may participate in human carcinogenesis by a similar mechanism.

Non-stereoselective formation of 3 alpha,7 alpha,12 alpha,24-tetrahydroxy-5 beta-cholestan-26-oic acid during cholic acid biosynthesis

Incubation of (25RS)-, (25R)- and (25S)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestan-26-oic acid (THCA, 6, 6a, 6b) and (24E)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholest-24-en-26-oic acid (7) with rat liver mitochondria gave all four stereoisomers (9a,9b,9c,9d) of 3 alpha,7 alpha,12 alpha,24-Tetrahydroxy-5 beta-cholestan-26-oic acid (TeHCA). The corresponding 27-nor analogs (10,11) were also converted non-stereoselectively to a 1:1 mixture of the epimeric 24-hydroxy compounds (12).

[Clinical investigation of clean intermittent catheterization]

We evaluated 120 patients with neurogenic bladder treated by clean intermittent self catheterization (CIC) in our department. These cases were divided into 2 groups: early treatment cases in which CIC started within 1 year after onset of dysuria, and late treatment cases in which CIC started after more than 1 year. Urinary tract infections (UTI) were recognized in 35% of the early treatment cases and 80% of the late treatment cases in the subsequent period. Pyelonephritis was experienced in 4% of the early treatment cases and 12% of the late treatment cases. Antibiotics therapy was considered unnecessary for asymptomatic UTIs. After CIC treatment, hydronephrosis detected by intravenous pyelography (IVP) and ultrasonography was improved in 18 of the 20 cases, and no cases showed deteriorated renal function. In the cases with neurogenic bladder after radical operations of the uterus or rectum, 45% of the early treatment cases have become free from CIC within 3 months postoperatively, and 84% eventually became free. Most of the late treatment cases have been continuing CIC. We considered that CIC was unnecessary when the residual urine was less than 100ml based on the periodical urinalysis and observation of renal function.