Differential effects of chronic stress in young-adult and old female mice: cognitive-behavioral manifestations and neurobiological correlates.

Stress-related psychopathology is highly prevalent among elderly individuals and is associated with detrimental effects on mood, appetite and cognition. Conversely, under certain circumstances repeated mild-to-moderate stressors have been shown to enhance cognitive performance in rodents and exert stress-inoculating effects in humans. As most stress-related favorable outcomes have been reported in adolescence and young-adulthood, this apparent disparity could result from fundamental differences in how aging organisms respond to stress. Furthermore, given prominent age-related alterations in sex hormones, the effect of chronic stress in aging females remains a highly relevant yet little studied issue. In the present study, female C57BL/6 mice aged 3 (young-adult) and 20-23 (old) months were subjected to 8 weeks of chronic unpredictable stress (CUS). Behavioral outcomes were measured during the last 3 weeks of the CUS protocol, followed by brain dissection for histological and molecular end points. We found that in young-adult female mice, CUS resulted in decreased anxiety-like behavior and enhanced cognitive performance, whereas in old female mice it led to weight loss, dysregulated locomotion and memory impairment. These phenotypes were paralleled by differential changes in the expression of hypothalamic insulin and melanocortin-4 receptors and were consistent with an age-dependent reduction in the dynamic range of stress-related changes in the hippocampal transcriptome. Supported by an integrated microRNA (miRNA)-mRNA expression analysis, the present study proposes that, when confronted with ongoing stress, neuroprotective mechanisms involving the upregulation of neurogenesis, Wnt signaling and miR-375 can be harnessed more effectively during young-adulthood. Conversely, we suggest that aging alters the pattern of immune activation elicited by stress. Ultimately, interventions that modulate these processes could reduce the burden of stress-related psychopathology in late life.

Induction of unscheduled DNA synthesis in rat stomach mucosa by glandular stomach carcinogens.

Induction of unscheduled DNA synthesis (UDS) (repair DNA synthesis) in stomach pyloric mucosa of the F344/- DuCrj rat was examined in in vitro organ cultures in the presence of tritiated thymidine ([3H]dThd) and hydroxyurea after administration of chemical carcinogens in vivo. The DNA fraction was extracted from the cultured tissue, and the incorporation of [3H]dThd into DNA was determined in a liquid scintillation counter. DNA concentration was determined spectrophotometrically with either diphenylamine or 3,5- diaminobenzoic acid. A good correlation between induction of UDS and site specificity of carcinogens was observed. The glandular stomach carcinogens N-methyl-N'-nitro-N-nitrosoguanidine (CAS: 70-25-7), N-ethyl-N'-nitro-N-nitrosoguanidine (CAS: 63885-23-4), N-propyl-N'-nitro-N-nitrosoguanidine, 4-nitroquinoline 1-oxide (CAS: 56-57-5), and N-nitroso-N-methylurethane (CAS: 615-53-2) induced UDS in the pyloric mucosa of the stomach. UDS could be detected 2-4 hours after administration of carcinogens in vivo by the present method. The forestomach carcinogens 1-methyl-1-nitrosourea (CAS: 684-93-5) and aristolochic acid (CAS: 1398-06-7) and the nongastric carcinogens 2-acetylaminofluorene (CAS: 53-96-3), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, 3-amino-1-methyl-5H-pyrido[4,3-b]indole, and dimethylnitrosamine (CAS: 62-75-9) did not induce UDS in the pyloric mucosa.

Characteristics of thyrotropin releasing hormone (TRH) receptors in rat brain.

Characteristics of TRH-receptors were studied in the rat central nervous system (CNS). Ion species, pH and temperature importantly influenced TRH-receptor binding. Subcellular distribution of TRH-receptor binding revealed that synaptic membranes had the greatest percentage of total sites. Scatchard analysis suggested that the rat CNS had two distinct TRH binding sites with apparent dissociation constants (Kd) of 5 X 10(09) M and 13 X 10(-8) M. Receptor activity is sensitive to trypsin and phospholipase A digestion, suggesting that protein and phospholipid moieties are essential for the binding of [3H]TRH. Thiol reagents reduced the binding activity of the receptor, suggesting that an intrachain disulfide bond may form an important constituent of the binding site for TRH. The TRH-receptor in the rat brain was successfully solubilized with non-ionic detergent Triton X-100. On gel chromatography with Sepharose 6B column, the solubilized TRH-receptor molecule eluted at the fraction corresponding to an apparent molecular weight of 300,000 daltons, with Stokes' radius of 5.8 nm. The regional distribution of TRH-receptor binding was examined to clarify the site of TRH action. The highest level of binding was in the hypothalamus, cerebral cortex and hippocampus, indicating that TRH affects the CNS function mainly through the limbic system, cerebral cortex and hypothalamus. Moreover, tricyclic anti-depressants and Li+ decreased the binding of [3H]TRH. These findings suggest that endogenous TRH and TRH receptor may play the role of a neurotransmission modulator in the brain to control emotional and mental functions.

Age-associated changes in the dopamine synthesis as determined by GTP cyclohydrolase I inhibitor in the brain of senescence-accelerated mouse-prone inbred strains (SAMP8).

Our objective in this study was to elucidate the mechanism underlying the decrease in dopamine (DA) levels in the brain with ageing We administered 2,4-diamino-6-hydroxypyrimidine (DAHP), an inhibitor of GTP cyclohydrolase I to senescence-accelerated mouse-prones (SAMP8), to inhibit DA and serotonin syntheses, and following immunohistochemical staining, analyzed the immunoreactive intensities (IR-Is) for DA in the nigrostriatal dopaminergic neurons by microphotometry. The DA-IR-Is in the substantia nigra pars compacta and neostriatum of young mice (2 months old) reached a minimal value 3 h after DAHP administration and returned to the control value 12 h after the administration. However, in aged mice (10 months old), the minimal value was reached 6 h after the administration and the value remained at approximately 70 and 80% of the control value at 24 and 72 h, respectively, after DAHP administration. The results suggest that DA turnover is lower in aged mice than in young mice.

Discrete regional distributions of thyrotropin releasing hormone (TRH) receptor binding in monkey central nervous system.

Thyrotropin releasing hormone (TRH) directly influences central nervous system (CNS) function, independent of its pituitary action. Although these CNS effects have been behaviorally characterized, information is not yet available on the precise regional distribution of its receptor. TRH receptor binding was examined in the monkey CNS by the radioreceptor assay for clarifying the site of TRH action. TRH was bound to brain tissue membranes via high-affinity (Kd = 5.9 x 10(-9) M) and low-affinity (Kd = 11.2 x 10(-8) M) components. TRH receptor binding varied dramatically throughout the monkey brain, with more than 40-fold variation. The limbic system contained the greatest amount of binding. The next highest areas were the cerebral cortex, hypothalamus, interpeduncular nucleus and periaqueductal gray matter of the midbrain. Receptor binding was very low or not detectable in the medial thalamus, cerebellum, brain stem, spinal cord and white matter. These data suggest that TRH has an effect on the CNS via limbic system, cerebral cortex and midbrain.

Effects of bromocriptine on receptor binding of methionine-enkephalin.

Bromocriptine inhibited the binding of methionine-enkephalin (ENK) to rat striatal synaptic membranes in a dose-dependent fashion. The bromocriptine IC50 was 16 micrometers. hill coefficients of bromocriptine were 0.7 and 0.3, suggesting that an allosteric effect was involved in bromocriptine inhibition of ENK binding to its receptor. These data suggest that at least a part of the therapeutic antiparkinsonian effect f bromocriptine is its allosteric effects on the ENK receptor, which influences the function of striatal dopamine neurons and/or of striatal cholinergic neurons.

Differentiation of agonist conformation and antagonist conformation in multiple opioid receptors.

To differentiate the opiate (naloxone) receptor and the enkephalin receptor in rat brain, we solubilized the receptor molecules by detergent and determined the molecular weights by gel filtration. The receptor preparation was bound to [3H] naloxone or [3H] Met5-enkephalin, and was solubilized by Triton X-100. On gel chromatography with a Sepharose 6B column, the agonist and the antagonist conformation of opioid receptors eluted as molecules with the molecular weights of 240,000, and 120,000 and with Stokes' radii of 5.5 nm and 4.3 nm, respectively. Further, it was also disclosed that Na+ was bound to the antagonist conformation of opioid receptors but not to the agonist conformation.

Transient appearance of tyrosine hydroxylase-immunoreactive non-catecholaminergic neurons in the medial geniculate nucleus of postnatal mice.

Tyrosine hydroxylase-immunoreactive (TH-ir) cells were found to appear transiently in the medial geniculate nuclear region of mice at postnatal day 7 (P7) by use of an avidin-biotin peroxidase complex (ABC) method for the first time. The numbers of TH-ir cells reached maximum between P14 and P21 and decreased until P29. These cells were GTP cyclohydrolase I-negative, aromatic L-amino acid decarboxylase-negative, and dopamine-negative. Thus, they do not belong to the catecholaminergic neuron system, because they lack dopamine production. The results suggest that TH in the cells in the medial geniculate nuclear region of mice has some new functions besides catecholamine biosynthesis.

Immunohistochemical colocalization of GTP cyclohydrolase I in the nigrostriatal system with tyrosine hydroxylase.

Immunohistochemical colocalization of GTP cyclohydrolase I (GCH) in the mouse nigrostriatal system with tyrosine hydroxylase or aromatic L-amino acid decarboxylase in the somata and terminals of GCH-positive catecholaminergic neurons are proved for the first time by a double-labeling immunofluorescence method with a confocal laser-scanning microscope. GCH-immunoreactive somata in the mouse substantia nigra have synaptic contacts with monoaminergic and non-monoaminergic terminals.

Eustachian tube cartilage and medial movement of lateral pharyngeal wall on phonation.

Several authors have demonstrated the importance of medial movement of the lateral pharyngeal wall in velopharyngeal closure upon phonation. However, it remains controversial what muscle is responsible for lateral pharyngeal wall movement and where is the main site of this movement. The purpose of this study was to address the above two unanswered questions. In 22 subjects (12 normal volunteers, 10 patients with cleft palate), lateral pharyngeal wall movement upon phonation was evaluated by using rapid magnetic resonance imaging (MRI). Before rapid MRI, their lateral pharyngeal wall movements were classified into three groups: the poor, moderate, and good, according to the findings of nasopharyngoscopy. Inward displacement of the eustachian tube cartilages upon phonation, which was quantified as distance ratio in the transverse plane of MR images, was compared with nasopharyngoscopic findings. In addition, the level of lateral pharyngeal wall movement was observed in the plane 5 mm lateral to the mid-sagittal plane of MR images. Inward displacement of the eustachian tube cartilage in the transverse plane of MR images was coincident with medial movement of lateral pharyngeal wall observed by nasopharyngoscopy in all 22 subjects. By using one-way analysis of variance, a statistically significant correlation was found between nasopharyngoscopic classification and distance ratio. The sagittal plane of MR images revealed that the main site of movement occurred at the level of the hard palate and above. It is concluded that medial movement of the lateral pharyngeal wall consists of inward displacement of the eustachian tube cartilage, which is caused by contraction of the levator veli palatini muscle, and that the primary site of this movement is at the level of the hard palate and above, where the eustachian tube, but not the superior constrictor muscle, exists.

Successful treatment of levodopa-induced neuroleptic malignant syndrome (NMS) and disseminated intravascular coagulation (DIC) in a patient with Parkinson's disease.

After 9 years of treatment for Parkinson's disease, a 68-year-old woman developed the complications of neuroleptic malignant syndrome (NMS) and disseminated intravascular coagulation (DIC) while she was still receiving levodopa, bromocriptine and amantadine hydrochloride. The patient displayed a high fever (40 degrees C), impaired consciousness, marked systemic muscle rigidity, tremor and bloody stools. The diagnosis of NMS and DIC was made on the basis of the symptoms and the results of blood serological tests. The antiparkinsonian drugs that had been administered until her admission to our hospital were continued unchanged, while the NMS was treated with dantrolene sodium and the DIC, with nafamostat mesilate. Both of the above-mentioned therapies were effective. The present case is rare in that the patient developed NMS and DIC during treatment and not after the discontinuation of the antiparkinsonian drugs.

Serovar, pathogenicity and antimicrobial susceptibility of erysipelothrix rhusiopathiae isolates from farmed wild boars (Sus scrofa) affected with septicemic erysipelas in Japan.

Six strains of Erysipelothrix rhusiopathiae were isolated from farmed wild boars with acute septicemic erysipelas during the period from 1983 to 1998 in Japan. All isolates belonged to serovar 1a or 2 (predominant serovars in swine). The 50 per cent lethal dose values of those isolates ranged from 10(1.3)to 10(6.2)colony forming units in mice. In swine, all isolates were virulent, capable of inducing localized or generalized urticarial lesions after intradermal inoculation. All of the isolates were resistant to oxytetracycline and/or dihydrostreptomycin. These observations suggest that E. rhusiopathiae strains isolated from wild boars may have aetiological significance in swine erysipelas.

Velopharyngeal closure and the longus capitis muscle.

The dynamic mechanism of velopharyngeal function not only in normal individuals but also in patients with velopharyngeal insufficiency, which is mainly related to cleft palate, has been the subject of considerable interest and controversy. Recently, in order to clarify velopharyngeal movement in the valvular action on phonation we examined dynamic MR images of this area taken in the transverse plane in parallel with the muscle sling of levator veli palatini. In cases in whom the closure pattern in that plane is circular, detailed observation revealed a very interesting result; that is, the longus capitis muscle, one of the group of anterior vertebral muscles, is directly involved in velopharyngeal valving function. It has not previously been reported that the longus capitis muscle acts as one of the velopharyngeal closure muscles, in addition to levator veli palatini. The present study demonstrated that contraction of the muscle contributed to velopharyngeal closure by forward movement of the pharyngeal wall.

Renal pelvic and ureteral carcinoma with huge hydronephrosis: US, CT, and MR findings.

A 78-year-old man presented huge hydronephrosis with a calculus in the left kidney, and underwent left nephroureterectomy under the diagnosis of renal pelvic and ureteral tumor. Histological examination disclosed renal pelvic and ureteral tumors featuring mixed histologic types of carcinoma. Magnetic resonance (MR) imaging was superior to computed tomography (CT) in its complete, detailed demonstration of the renal pelvic lesions. The imaging characteristics of CT, MR imaging, ultrasonography, and retrograde ureterography were discussed in the report.

Development of a simple spasticity quantification method: effects of tizanidine on spasticity in patients with sequelae of cerebrovascular disease.

A simple method that can be performed at the bedside using a spring balance was developed in order to quantify spasticity. The effects of tizanidine on spasticity were evaluated in 30 patients with sequelae of cerebrovascular disease using this method. Treatment with tizanidine was effective in 60% of the patients; there were high correlations between spasticity before and after tizanidine administration and the severity of symptoms and also between the degree of improvement in spasticity and in that of the symptoms. Atonic seizures, due to overdose of tizanidine, were observed in only one patient. The simple spasticity quantification method developed was useful for monitoring tizanidine administration in order to prevent drug overdose. The method appears to be very useful for evaluating the degree of spasticity at the bedside and in measuring the effects of antispastic drugs.

Clinical, pathological and mineralogical features in two autopsy cases of workers exposed to agalmatolite dust.

An agalmatolite miner and processor showed large shadows at the bilateral hila accompanied by surrounding emphysematous changes and irregular shadows on chest X-ray films. Chest CT scans were characterized by a mixture of tiny irregular structures and small round opacities. Histopathological examination revealed massive fibrosis, which corresponded to large shadows, but only a small number of typical silicotic nodules, indicating mixed dust pneumoconiosis. Mineralogical examination of the autopsy lungs showed quartz, pyrophyllite, mica, and kaolinite. Quartz accounted for 70% of the amount of all mineral dust in both patients, but pyrophyllite accounted for 10.8% and 14.4%. The pulmonary mineral dust composition in the two patients was well consistent with the mineral composition of the raw clays in the agalmatolite mine. In the two patients, chest X-ray findings and histopathological findings of the lungs also suggested agalmatolite pneumoconiosis, which was confirmed by mineral analysis of the lungs.

[Successful treatment of levodopa-induced neuroleptic malignant syndrome (NMS) with disseminated intravascular coagulation (DIC) in a patient with Parkinson's disease].

A 77-year-old woman with a 9 years history of Parkinson's disease was admitted to our hospital because of high fever, disturbance of consciousness, increased muscular rigidity and abnormal involuntary movements. She was continuously treated with levodopa + carbidopa (Menesit) 300 mg and amantadine 150 mg every day until admission. On admission, the pulse rate was 102 per minute, blood pressure 90/40 mmHg, body temperature 40.9 degrees C, and bloody stool was noticed. On laboratory examination, erythrocyte sedimentation rate was 6 mm/h, thrombocytes 8.1 X 10(4)/microliters, fibrinogen 91 mg/dl, FDP 40 mg/ml, suggesting DIC. According to her biochemical examination, serum GOT (167 u), GPT (119 u), CPK (847 IU/l), BUN (53.9 mg/dl) and myoglobin (10,370 ng/ml) were increased. These laboratory data indicated that she was suffering from neuroleptic malignant syndrome (NMS) with disseminated intravascular coagulation (DIC). On diagnosis of NMS associated with DIC, she was treated with dantrolene and FUT-175. Dantrolene was effective on the elevated COK level and FUT-175 was effective on the DIC, and symptoms of NMS and DIC were completely improved after a period of 14 days. Patients with Parkinson's disease have been suspected to have a low incidence of DIC, and this may be the first case report on successful treatment of levodopa-induced NMS with DIC in the patient with Parkinson's disease.

[Development of factor VIII inhibitor in three non-hemophiliac patients].

Infrequently, inhibitors against factor VIII can develop in non-hemophiliac patients and cause serious bleeding. In the last year, we have experienced 3 non-hemophiliac patients who developed factor VIII inhibitors. Here, we describe the clinical courses of the three patients and the characteristics of the inhibitors. Case 1: A 69-year-old man underwent a partial gastrectomy because of early gastric cancer, and one month later developed signs of a bleeding tendency such as hematemesis, tarry stools and intramuscular hemorrhage. Blood coagulation tests revealed prolongation of the activated partial thromboplastin time (aPTT), which had been normal on admission. Case 2: A 78-year-old woman with no previous disease history developed generalized subcutaneous purpura. Blood coagulation tests performed on admission revealed a prolonged aPTT. Case 3: A 30-year-old man was admitted to an emergency hospital because of left intrapleural hemorrhage and liver injury caused by a traffic accident. Two months later, a hematoma developed at the site of drainage in the left chest, and blood coagulation tests revealed prolongation of the aPTT, which had been normal on admission. Plasma factor VIII procoagulant activities in cases 1, 2 and 3 were 3%, 1% and 5%, respectively. The respective factor VIII inhibitor titers were 78, 870 and 0.5 Bethesda units/ml. The immunoglobulin class and subclass of the inhibitors examined by an ELISA method were: case 1, IgG1 and 4; case 2, IgG2 and 4 (dominant); case 3, IgG4. In cases 1 and 3, the patients recovered after glucocorticoid therapy, but in case 2 the patient died of intraperitoneal hemorrhage despite receiving two courses of methylprednisolone pulse therapy. The above clinical experience suggests that patients, who develop high titers of inhibitors may be refractory to ordinary immunosuppressive therapy, and therefore more aggressive therapy such as plasma exchange and/or bypass therapy using activated prothrombin complex concentrates or an activated factor VII preparation should be considered.

[Significance of antitumor effects and immunological response on endogenously induced LAK therapy for primary or metastatic liver tumor].

Nineteen patients with metastatic liver tumor (9 of gastric cancer, 5 of colon cancer, 2 of pancreatic cancer, one each of mammary cancer, cholecystic cancer, carcinoid of biliary tract) and one patient with primary liver cancer were treated by endogenously induced LAK therapy consisting of transhepatic arterial infusion with ADM or MMC for induction therapy and OK-432 and rIL-2 (TGP-3) for immunotherapy. The following results were obtained. 1) Clinical response for liver tumor showed no CR but 8 cases of PR, for an overall response rate of 42.1%. 2) Reduced tumor marker value was noted in 76.5% cases, and 50% survival term became 349 days after the therapy. 3) Many CD4 and CD8 positive mononuclear cells had infiltrated around liver tumor after therapy by immuno-histochemical staining of surface marker. 4) NK activity of peripheral blood lymphocytes was markedly reduced soon after the therapy and continued for about 4-7 days, while in cases of combined subcutaneous administration with OK-432, NK activity showed only a slight decrease.

[A case of hepatocellular carcinoma (HCC) with a huge tumor thrombus in the right atrium].

A case of HCC with a huge tumor thrombus in the right atrium is reported. CT and celiac angiography revealed HCC in the liver. Inferior vena cavography and cardiac blood pool scintigraphy demonstrated a large defect in the right atrium, and 67Ga-citrate scintigraphy showed a lesion of abnormal accumulation in the right atrium. With these findings, diagnosis of HCC with a tumor thrombus in the right atrium was made, and the clinical diagnosis was confirmed by autopsy.