Effect of Perospirone on p300 Electrophysiological Activity and Social Cognition in Schizophrenia: A Three-dimensional Analysis with (s)loreta

The purpose of this study was to determine if perospirone, a second generation antipsychotic drug and partial agonist at serotonin-5-HT1A receptors, enhances electrophysiological activity, such as event-related potentials (ERPs), in frontal brain regions, as well as cognitive function in subjects with schizophrenia. P300 current source images were obtained by means of standardized low resolution brain electromagnetic tomography (sLORETA) before and after treatment with perospirone for 6 months. Perospirone significantly increased P300 current source density in the left superior frontal gyrus, and improved positive symptoms and performance on the script tasks, a measure of verbal social cognition. Perospirone also tended to enhance verbal learning memory in patients with schizophrenia. There was a significant correlation between the changes in P300 amplitudes on the left frontal lead and those in social cognition. These results suggest the changes in three-dimensional distribution of cortical activity, as demonstrated by sLORETA, may mediate some of the actions of antipsychotic drugs. the distinct cognition-enhancing profile of perospirone may be related to its actions on 5-HT1A receptors.

Truncation mutations abolish chromatin-associated activities of adenomatous polyposis coli

The adenomatous polyposis coli (APC) is a tumor suppressor whose loss of function leads to colon cancer. APC shuttles between the nucleus and cytoplasm, however its role in the nucleus remains elusive. We have found that nuclear APC specifically associates with transcriptionally active chromatin through structural elements located downstream to the region of frequent truncation mutations found in colorectal tumors. We show that a recombinant APC fragment comprising such elements associates in vivo with euchromatin and preferentially binds in vitro to acetylated histone H3. Induction of DNA double-strand breaks (DSB) stimulates accumulation of APC at the damaged DNA chromatin marked by histone H2AX and S139-phosphorylated histone H2AX. A nuclear complex containing the DNA-dependent protein kinase catalytic subunit (DNAPKcs) and APC associates with chromatin in response to DNA DSB. APC knockdown with siRNA decreased the rate of DNA DSB-induced S139 histone H2AX phosphorylation in cells expressing endogenous full-length APC, but not in colon cancer cells with its truncation mutants, whereas ectopic APC expression stimulated the H2AX phosphorylation regardless of the type of endogenous APC. Our data suggest that APC involves in the DSB DNA repair and that truncation mutations impair chromatin-associated functions of APC.

[Pseudomesotheliomatous carcinoma of the lung]

Pseudomesotheliomatous carcinoma is the lung cancer with marked pleural extension resembling malignant pleural mesothelioma on diagnostic imaging. We report a rare case of pseudomesotheliomatous carcinoma of the lung in a 72-year-old man. The patient had complained of dyspnea and a chest roentgenogram showed right pleural effusion. Computed tomography (CT) of the chest revealed diffuse irregular pleural thickening, which mimicked pleural malignant mesothelioma. Pleural tissue sampling was performed to obtain definitive diagnosis by video-assisted thoracoscopic surgery. At the operation. the tumor was found to have a spread along the pleural surface and primary lesion was not detected in the right lung parenchyma. Immunohistochemically, the tumor was positive for carcinoembryonic antigen (CEA), but negative for calretinin, thrombomodulin, and pulmonary surfactant apoprotein. Final diagnosis was adenocarcinoma of the lung.

Identification and characterization of Asef2, a guanine-nucleotide exchange factor specific for Rac1 and Cdc42

The tumor suppressor adenomatous polyposis coli (APC) is mutated in sporadic and familial colorectal tumors. APC interacts with the Rac1-specific guanine-nucleotide exchange factor (GEF) Asef, which contains an APC-binding region (ABR) in addition to Dbl homology (DH), Pleckstrin (PH) and Src homology 3 (SH3) domains. APC stimulates the GEF activity of Asef, and thereby regulates cell adhesion and migration. Here, we have identified a second Asef, termed Asef2, that shows significant structural and functional similarities to Asef. We found that both the N-terminal ABR and SH3 domains of Asef2 are responsible for its interaction with APC. When expressed in HeLa cells, a mutant Asef2 lacking the ABR and SH3 domains, Asef2-DeltaABR/SH3, induced increases in the levels of the active forms of Rac1 and Cdc42. Full-length Asef2 also showed this activity when co-transfected with truncated mutant APC expressed in colorectal tumor cells. Consistent with this, either Asef2-DeltaABR/SH3 or Asef2 plus truncated mutant APC stimulated lamellipodia formation in MDCK cells and filopodia formation in HeLa cells. Furthermore, RNA interference experiments showed that Asef2 is required for migration of colorectal tumor cells expressing truncated APC. These results suggest that similar to Asef, Asef2 plays an important role in cell migration, and that Asef2 activated by truncated mutant APC is required for aberrant migration of colorectal tumor cells.

Deregulated expression of a novel component of TFTC/STAGA histone acetyltransferase complexes, rat SGF29, in hepatocellular carcinoma: possible implication for the oncogenic potential of c-Myc

c-Myc N-terminal conserved domains, MbI and MbII, are essential for c-Myc-mediated transformation and transactivation. These domains recruit the STAGA (SPT3-TAF9-GCN5-acetyltransferase) coactivator complex, but not TFTC (TATA-binding protein-free TAF-containing) to the target gene promoter. Although components of this complex are well conserved between yeast and mammals, four mammalian orthologs of yeast SPT8, SPT20, SGF11 and SGF29 remain to be identified. Here, we isolated a rat ortholog of yeast SGF29, a component of yeast SAGA (SPT-ADA-GCN5-acetyltransferase) complex. Both rat (r) SGF29 and c-myc mRNAs were overexpressed in five out of the eight tested rodent tumor cells. rSGF29 directly interacted with rADA3 and co-immunoprecipitated with two other TFTC/STAGA components, rGCN5 and rSPT3. rSGF29 was recruited to the c-Myc target gene promoters together with c-Myc, and it activated c-Myc target gene expressions. Downregulation of rSGF29 suppressed the expression of c-Myc target genes and inhibited anchorage-independent growth and tumorigenicity and lung metastasis of rat hepatoma K2 cells when injected into nude mice. These results show that rSGF29 is a novel component of TFTC/STAGA complexes and could be involved in the c-Myc-mediated malignant transformation.

Protein kinases as potential targets for the treatment of pathological pain

Pathological pain or clinical pain refers to tissue injury-induced inflammatory pain and nerve injury-induced neuropathic pain and is often chronic. Pathological pain is an expression of neural plasticity that occurs both in the peripheral nervous system (e.g., primary sensory nociceptors), termed peripheral sensitization, and in the central nervous system (e.g., dorsal horn and brain neurons), termed central sensitization. Our insufficient understanding of mechanisms underlying the induction and maintenance of injury-induced neuronal plasticity hinders successful treatment for pathological pain. The human genome encodes 518 protein kinases, representing one of the largest protein families. There is growing interest in developing protein kinase inhibitors for the treatment of a number of diseases. Although protein kinases were not favored as targets for analgesics, studies in the last decade have demonstrated important roles of these kinases in regulating neuronal plasticity and pain sensitization. Multiple protein kinases have been implicated in peripheral and central sensitization following intense noxious stimuli and injuries. In particular, mitogen-activated protein kinases (MAPKs), consisting of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK), are downstream to many kinases and are activated in primary sensory and dorsal horn neurons by nociceptive activity, growth factors and inflammatory mediators, contributing to the induction and maintenance of pain sensitization via posttranslational, translational, and transcriptional regulation. MAPKs are also activated in spinal glial cells (microglia and astrocytes) after injuries, leading to the synthesis of inflammatory mediators/neuroactive substances that act on nociceptive neurons, enhancing and prolonging pain sensitization. Inhibition of multiple kinases has been shown to attenuate inflammatory and neuropathic pain in different animal models. Development of specific inhibitors for protein kinases to target neurons and glial cells will shed light on the development of new therapies for debilitating chronic pain.

Wnt signalling and the actin cytoskeleton

The tumour suppressor adenomatous polyposis coli (APC) is mutated in sporadic and familial colorectal tumours. APC binds to beta-catenin, a key component of the Wnt signalling pathway, and induces its degradation. In addition to this role, there is increasing evidence for additional roles of APC, including the organization of cytoskeletal networks. APC interacts with microtubules and accumulates at their plus ends in membrane protrusions. Also, it has been reported that APC is associated with the plasma membrane in an actin-dependent manner. Moreover, APC interacts with IQGAP1, an effector of Rac1 and Cdc42, and APC-stimulated guanine nucleotide exchange factor (Asef), a Rac1-specific guanine nucleotide exchange factor (GEF). IQGAP1 mediates association of APC with cortical actin in the leading edge of migrating cell and both proteins are required for cell polarization and directional migration. APC interacts with Asef and stimulates its activity, thereby regulating the actin cytoskeletal network, cell morphology, adhesion and migration. Truncated mutant APCs present in colorectal tumour cells activate Asef constitutively and contribute to their aberrant migratory properties, which may be important for adenoma formation as well as tumour progression to invasive malignancy.

Primary erythrocytosis in a Japanese black calf: a case report

An 8-month-old Japanese Black heifer with severe erythropoietic symptoms was subjected to clinical, histological and cytological examinations. During the 1 month clinical observation period, severe increases in RBC count, packed cell volume and haemoglobin concentration were observed. The plasma erythropoietin (Epo) concentration of the heifer (20.7 mIU/ml) was similar to that observed in normal control heifers. Blood gas examinations of the arterial and venous blood revealed low levels of partial pressure O(2) (PaO(2)), partial pressure CO(2) (PaCO(2)) and O(2) saturation (SaO(2)), while the blood pH was within the normal range. Gross lesions could not be detected. However, microscopic observation revealed severe proliferation of erythroblasts in the bone marrow and in the spleen without evidence of neoplastic changes. Based on these clinical and pathological examinations, we diagnosed the heifer as being the first case of primary erythrocytosis in Japanese Black cattle.

Postoperative host responses in elderly patients after gastrointestinal surgery

BACKGROUND/AIMS

The age-associated dysregulation of hemodynamic, metabolic and immune responses contributes to the high incidence of complications after major abdominal surgery.

METHODOLOGY

Ninety-five patients who underwent gastric resection (n=51) and colorectal resection (n=44) were divided according to age into Groups A (n=45, less than 70 years old), B (n=30, 70-79 years) and C (n=20, over 80 years). Flow cytometric analysis of CD4+ lymphocytes for interferon (IFN)-gamma and interleukin (IL)-4 production determined the Th1/2 balance. Energy expenditure was measured by indirect calorimetry, and hemodynamics were studied using pulse dye densitometry.

RESULTS

Surgical procedures, operating time, blood loss and morbidity did not significantly differ among the three groups. The cardiac index (CI) in group A and B increased significantly over preoperative levels until POD 3, but there were no significant perioperative changes in the CI levels of group C. Resting energy expenditure levels changed similarly to those of CI. The postoperative Th1/2 ratio decreased from young to elderly to very elderly patients, although no differences were significant before surgery. The postoperative percentage of CD4+IFN-gamma +T cells (Th1) in group C decreased significantly despite of no significant changes in that of group A and B. In contrast, the ratio of CD4+IL-4+T cells (Th2) in the all groups significantly increased after surgery.

CONCLUSIONS

Host responses in elderly patients after major abdominal surgery were more hyperdynamic and hypermetabolic than those of young patients. Postoperative dysregulation of the Th1/2 balance was also associated with aging. However, host responses appear to significantly differ between elderly and very elderly patients.

Prognostic predictive values of serum cytochrome c, cytokines, and other laboratory measurements in acute encephalopathy with multiple organ failure

AIMS

To evaluate the prognostic predictive values of cytochrome c, cytokines, and other laboratory measurements in serum collected during neurological onset in acute encephalopathy with multiple organ failure.

METHODS

In addition to general laboratory examinations, the concentrations of cytochrome c (apoptosis marker) and cytokines (inflammatory markers) were measured in serum samples collected at the initial phase in 29 patients with acute encephalopathy. The obtained values were evaluated as predictors for the development of severe encephalopathy.

RESULTS

Cytochrome c, tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble TNF-receptor 1 (sTNF-R1), and aspartate aminotransferase (AST) concentrations at the initial phase were high and correlated well with patient outcome. High concentrations of serum cytochrome c (>45 ng/ml), sTNF-R1 (>2000 pg/ml), AST (>58 IU/dl), IL-6 (>60 pg/ml), and TNF-alpha (>15 pg/ml) predicted an unfavourable prognosis (sequelae and death) at 93%, 79%, 82%, 77%, and 60%, respectively. The specificity of those markers was 100%, 89%, 83%, 100%, and 100%, respectively.

CONCLUSIONS

Serum cytochrome c is the most sensitive and specific predictor for the development of severe encephalopathy at the initial phase. Results suggest that this marker might be used to guide decisions regarding the start of the initial treatment and further intensive care.

Phase separation in A-site-ordered perovskite manganite LaBaMn2O6 probed by 139La and 55Mn NMR

139La- and 55Mn-NMR spectra demonstrate that the ground state of the A-site-ordered perovskite manganite LaBaMn2O6 is a spatial mixture of the ferromagnetic and antiferromagnetic regions, which are assigned to the metallic and the insulating charge ordered state, respectively. This exotic coexisting state appears below 200 K via a first-order-like formation of the antiferromagnetic charge ordered state inside the ferromagnetic metal one. The Mn spin-spin relaxation rate indicates that the ferromagnetic region coexisting with the antiferromagnetic one in LaBaMn2O6 is identical to the bulk ferromagnetic metal phase of the disordered form La0.5Ba0.5MnO3 in spite of the absence of A-site disorder. This suggests a mesoscopic rather than nanoscopic nature of the ferromagnetic region in LaBaMn2O6.

Clinicopathological features and the prognosis of IgA nephropathy in Japanese children on long-term observation

AIMS

Clinicopathological features were investigated to clarify the ultimate prognosis and prognostic indicators for patients with IgA nephropathy in Japanese children.

METHODS

We evaluated the outcomes of 181 patients in whom IgA nephropathy was diagnosed before the age of 15 years since September 1979 and followed-up at least for three years with regard to clinical data at the onset of symptoms and renal histologic data.

RESULTS

After mean follow-up of 7.3 years from onset, 91 patients of 181 (50.3%) were in clinical remission at the last examination, 24 (13.2%) had isolated hematuria, 59 (32.6%) had hematuria and proteinuria. Eighteen of 59 (9.9%) had proteinuria more than 1 g per 24 hours. Hypertension was observed in 12 cases and 7 (3.9%) developed end-stage renal disease. Except 7, no patient had reduced renal function and elevated serum creatinine at the final follow-up. Predicted renal survival rate from onset was 92.3% at 10 years and 89.1% at 20 years. In multivariable analysis, age at onset and chronic changes of tubulointerstitium were associated with poor outcome.

CONCLUSIONS

Of 181 children with IgA nephropathy, 50% regressed, remaining 46% had hematuria and/or proteinuria and 4% of patients lapsed into end-stage renal disease. Our results indicate that childhood IgA nephropathy has a benign course and the risk for end-stage renal disease is lower than that of adults. Age at onset and tubulointerstitial lesions were the strong predictors of a progressive course of childhood IgA nephropathy.

Soluble TNF receptors and albuminuria in non-obese Japanese type 2 diabetic patients

The aim of this study was to investigate the relationships between albuminuria and tumor necrosis factor (TNF)-alpha or soluble TNF receptors (sTNF-R1, sTNF-R2) in eighty-eight non-obese Japanese type 2 diabetic patients stratified into two groups according to albuminuria status-microalbuminuria or normoalbuminuria. Patients with microalbuminuria were older and had significantly higher concentrations of sTNF-R1 and sTNF-R2 than those with normoalbuminuria. There was, however, no significant difference in sex, diabetes duration, smoking, BMI, systolic and diastolic blood pressure, HbA (1c), serum creatinine, and lipid profile between the two groups. Although serum TNF-alpha was positively correlated to serum sTNF-R1 and sTNF-R2, serum TNF-alpha level did not differ with respect to albuminuria. Univariate regression analysis showed that urinary albumin concentration was positively correlated to age (r=0.380, p<0.001), serum creatinine (r=0.214, p<0.05) and concentrations of sTNF-R1 (r=0.364, p<0.001) and sTNF-R2 (r=0.342, p<0.005). Other variables, including TNF-alpha, were not associated with albuminuria. Multiple regression analyses showed that urinary albumin concentration was independently predicted by the level of sTNF-R1 (F=32.1), which explained 26.3% of the variability of urinary albumin concentration. From these results, it can be concluded that serum soluble TNF receptor is an important independent factor associated with albuminuria in non-obese Japanese type 2 diabetic patients.

Comparison of air displacement plethysmograph and bioelectrical impedance for assessing body composition changes during weight loss in Japanese women

OBJECTIVE

To investigate the difference between air displacement plethysmograph (ADP) and bioelectrical impedance (BI) for assessing body composition changes during weight loss in Japanese women.

DESIGN

Cross-sectional and longitudinal investigation study.

SUBJECTS

In a first cross-sectional study, we used data of 7380 Japanese women aged 14-83 years [body mass index (BMI): 22.6 +/- 3.7 kg/m(2)] at baseline. Among the participants, we used data of 54 women (BMI: 25.9 +/- 3.9 kg/m(2)) for a 5-month follow-up study.

MEASUREMENTS

Body fat percentage was evaluated by ADP and BI, and body fat (kg) and lean body mass (kg) were calculated. Anthropometric parameters, such as height, weight, BMI, waist circumference, hip circumference and waist hip ratio, were also measured. In a second longitudinal study, they were also investigated before and after the study.

RESULTS

In a first cross-sectional study, body fat percentage was 31.2 +/- 7.0% in ADP and 25.7 +/- 6.8% in BI. A significant relationship was observed between ADP and BI (r = 0.761, p < 0.01). In a second longitudinal study, body weight was significantly reduced. There were significant method (ADP vs. BI) and time (pre and post) effects but no interactions in assessing body fat percentage. There was a significant relationship between ADP and BI in body fat percentage, body fat and lean body mass. Delta body fat percentage (r = 0.386, p < 0.01) and delta body fat (r = 0.556, p < 0.01) measured by ADP were weakly correlated with those measured by BI. However, delta lean body mass measured by ADP was not correlated with that measured by BI.

CONCLUSION

There was a discrepancy between ADP and BI for assessing body composition changes in Japanese women. ADP is preferentially recommended for evaluating body composition.

Morphological brain changes associated with Schneider's first-rank symptoms in schizophrenia: a MRI study

BACKGROUND

Schneider's first-rank symptoms involve an alienated feature of the sense of one's own mental or physical activity. To clarify the brain morphological basis for the production of these symptoms, volumes of the frontal and medial temporal regions and their clinical correlates were examined in patients with schizophrenia.

METHOD

Twenty-two patients with schizophrenia and 44 age- and gender-matched healthy control subjects were included. All patients were in their psychotic episodes with definite Schneiderian symptoms, rated by using the Scale for Assessment of Positive Symptoms. Volumetric measurements of high-resolution magnetic resonance imaging were performed in the prefrontal area, cingulate gyrus, and precentral gyrus, and the medial temporal structures such as the amygdala, hippocampus, and parahippocampal gyrus.

RESULTS

Patients had significantly decreased volumes in the cingulate gray matter and the amygdala compared to controls. In the patient group, Schneiderian symptom severity showed significant inverse correlations with volumes of the right posterior cingulate gray matter and of the left anterior parahippocampal gyrus.

CONCLUSIONS

Schneiderian symptoms may be associated with morphological abnormalities in the limbic-paralimbic regions such as the cingulate gyrus and parahippocampal gyrus, which possibly serve the self-monitoring function and the coherent storage and reactivation of information.

Components and fractions for differently bound water molecules of dipalmitoylphosphatidylcholine–water system as studied by DSC and 2H-NMR spectroscopy

Differently bound water molecules of dipalmitoylphosphatidylcholine (DPPC)-H2O system were investigated with differential scanning calorimetry (DSC). According to a method previously reported by us, the ice-melting DSC curves of the DPPC-H2O samples of varying water contents were deconvoluted into multiple components, and the ice-melting enthalpies for the individual deconvoluted components were used to estimate average molar ice-melting enthalpies for freezable interlamellar and bulk waters, respectively. With these average molar ice-melting enthalpies, the numbers of differently bound water molecules of the DPPC-H2O system were calculated at varying water contents and were used to construct a water distribution diagram of this system. Furthermore, to evaluate the reliability of the present DSC deconvolution method, 2H-NMR T1 measurements of DPPC-2H2O system were carried out at 5 degrees C of the gel phase temperature, and components and fractions for differently bound water (2H2O) molecules were estimated from the analysis of nonexponential magnetization recovery curves.

Characterization of a point mutation in the parC gene of Mycoplasma bovirhinis associated with fluoroquinolone resistance

Quinolone-resistant (QR) mutants of Mycoplasma bovirhinis strain PG43 (type strain) were generated by stepwise selection in increasing concentrations of enrofloxacin (ENR). An alteration was found in the quinolone resistance-determining region (QRDR) of the parC gene coding for the ParC subunit of topoisomerase IV from these mutants, but not in the gyrA, gyrB, and parE gene coding for the GyrA and GyrB subunits of DNA gyrase and the ParE subunit of topoisomerase IV. Similarly, such an alteration in QRDR of parC was found in the field isolates of M. bovirhinis, which possessed various levels of QR. The substitution of leucine (Leu) by serine (Ser) at position 80 of QRDR of ParC was observed in both QR-mutants and QR-isolates. This is the first report of QR based on a point mutation of the parC gene in M. bovirhinis.

Relationship between C-reactive protein and visceral adipose tissue in healthy Japanese subjects

AIM

Recent studies have suggested that the elevated C-reactive protein (CRP) levels are associated with body fat, especially visceral adipose tissue, but most of them were investigated in Westerners who had higher body mass index (BMI) than Asians. To investigate the association between CRP concentrations, parameters of visceral obesity, the insulin resistance syndrome and carotid atherosclerosis in healthy Japanese who had a lower BMI than Westerners.

METHODS

We explored the relationships between fatness and visceral obesity parameters [by anthropometry, bioelectrical impedance analysis and abdominal computed tomography (CT)] and CRP (high sensitivity) and examined their associations with components of insulin resistance syndrome, interleukin-6 (IL-6), tissue necrosis factor-alpha (TNF-alpha) and intima-media thickness (IMT) of common carotid arteries (CCAs) by ultrasonograms in 116 healthy Japanese subjects.

RESULTS

In crude regression analyses, CRP was significantly associated with measures of obesity. After adjustment for age, gender and smoking, the association with CRP was stronger for parameters of visceral obesity (waist circumference, waist-to-hip ratio and visceral adipose tissue accumulation) than for other parameters of obesity. IL-6 and TNF-alpha were not associated with CRP. Blood pressure (BP), metabolic variables and CCA-IMT were also significantly associated with CRP. But, after being adjusted for age, gender, smoking and BMI, BP and high-density lipoprotein cholesterol (HDLc) were significantly associated.

CONCLUSION

CRP level is associated with visceral adipose tissue and is significantly associated with the components of insulin resistance syndrome in healthy Japanese subjects. These data support a possible role of visceral adipose tissue in inflammation component of atherosclerosis, and further studies are needed to study the mechanism of CRP elevation caused by visceral adipose tissue.

Membranoproliferative glomerulonephritis associated with hereditary deficiency of the 4th component of complement

A 10-year-old female patient was found positive for urine protein and occult blood on Japanese school urinary screening. Examination of the blood was normal except low values of the complement system with CH50 13.5 U/ml, C3 45 mg/dl and C4 3 mg/dl. Renal biopsy demonstrated a focal membranoproliferative glomerulonephritis (MPGN). As for the activity of each component of the complement in the early stage of the disease, the C4 activity was markedly declined and the activity of classical pathway component was also decreased, but the activity of alternative pathway component was normal. On the HLA examination, the patient demonstrated a C4 double null haplotype (C4A2, Q0, BQ0 phenotype). A null C4 gene at both the C4A and C4B loci was found in her mother, aunt and grandfather on the mother's side and C4B null allele in her father and her grandmother on the mother's side. The development of the disease is found in 1 case and not in the other, although both have the genetic defect and the mechanism by which the complement is activated remains unknown. Thus, there appear to be many subjects to be studied as to the relationship between the defect of C4 gene and immune competence.

Modulation by adenosine of aδ and c primary-afferent glutamatergic transmission in adult rat substantia gelatinosa neurons

The present study examined the actions of adenosine on monosynaptic Adelta and C primary-afferent excitatory postsynaptic currents (EPSCs) recorded from substantia gelatinosa (SG) neurons of an adult rat spinal cord slice. In 67% of the neurons examined, adenosine reversibly decreased the amplitude of the Adelta-fiber EPSC, while in 13% of the neurons the amplitude was reduced or unaffected, which was followed by its increase persisting for several minutes after adenosine washout. The remaining neurons did not exhibit a change in the amplitude. The reduction in Adelta-fiber EPSC amplitude by adenosine was dose-dependent with an effective concentration for half-inhibition (EC50) value of 217 microM. When examined by using a paired-pulse stimulus, a ratio of the second to first Adelta-fiber EPSC amplitude under the reduction was larger than that of EPSC amplitude in the control, suggesting a presynaptic action of adenosine. In 69% of the neurons tested, the C-fiber EPSC was reversibly decreased in amplitude by adenosine (100 microM) by an extent comparable to that of Adelta-fiber EPSC; the remaining neurons were without adenosine actions. Similar inhibitory actions of adenosine were also seen in neurons where both Adelta-fiber and C-fiber EPSCs were elicited. Similar reduction in the Adelta-fiber or C-fiber EPSC amplitude was induced by an A1 adenosine-receptor agonist, N6-cyclopentyladenosine (1 microM), and the adenosine-induced reduction was not observed in the presence of an A1 antagonist, 8-cyclopentyl-1,3-dipropylxanthine (1 microM). An A2a agonist, CGS 21680 (1 microM), did not significantly affect the Adelta-fiber EPSC amplitude. It is concluded that adenosine presynaptically inhibits monosynaptic Adelta-fiber and C-fiber transmission by a similar extent through the activation of the A1 receptor in many but not all SG neurons; this could contribute to at least a part of antinociception by intrathecally administered adenosine analogues and probably by endogenous adenosine.

Gray matter features of schizotypal disorder patients exhibiting the schizophrenia-related code types of the Minnesota Multiphasic Personality Inventory

OBJECTIVE

Previous studies have suggested that several code types of the Minnesota Multiphasic Personality Inventory (MMPI) are useful markers for identifying schizophrenia. We hypothesized that schizotypal disorder (STD) patients with such schizophrenia-related code types have the morphological brain abnormalities associated with schizophrenia.

METHOD

Voxel-based morphometric analysis with statistical parametric mapping (SPM) 99 software was used to investigate the differences in brain morphology between 14 STD patients with the schizophrenia-related code types of the MMPI and 28 normal individuals.

RESULTS

The STD patients showed significantly decreased gray matter volume in the insular regions bilaterally and in the left entorhinal cortex, compared with the controls.

CONCLUSION

Our findings suggest that STD patients with the schizophrenia-related code types have volume reductions in these regions as an endophenotype that overlaps with schizophrenia.

Isolation of Mycoplasmas from nasal swabs of calves affected with respiratory diseases and antimicrobial susceptibility of their isolates

Nasal swabs of 293 calves were examined for Mycoplasma. The samples were collected from calves affected with respiratory diseases on 71 farms in various parts of Japan between 1996 and 1997. Mycoplasma bovirhinis was isolated from 47 of 293 calves (16.0%). Mycoplasma alkalescens, M. bovis, M. arginini, M. bovigenitalium and Acholeplasma spp. were isolated from 19 (6.5%), seven (2.4%), four (1.4%), four (1.4%) and 18 (6.1%) calves, respectively. Pasteurella multocida and P. haemolytica were isolated from 60% of Mycoplasma-positive calves. However, other bacteria were not isolated from calves. To evaluate the antimicrobial susceptibility of their isolates, 68 M. bovirhinis, 21 M. alkalescens and 10 M. bovis strains were examined for 12 antimicrobial agents. All isolates showed higher susceptibility to tiamulin than to the other drugs used in the study. However, erythromycin had no effect on any of the Mycoplasma strains studied. The field isolates were less susceptible than the type strains to some drugs, such as spiramycin, oxytetracycline and tylosin.

Gapless magnetic and quasiparticle excitations due to the coexistence of antiferromagnetism and superconductivity in CeRhIn5: a study of 115In NQR under pressure

We report systematic measurements of ac susceptibility, nuclear-quadrupole-resonance spectrum, and nuclear-spin-lattice-relaxation time (T1) on the pressure (P)-induced heavy-fermion superconductor CeRhIn5. The temperature (T) dependence of 1/T(1) at P=1.6 GPa has revealed that antiferromagnetism (AFM) and superconductivity (SC) coexist microscopically, exhibiting the respective transition at T(N)=2.8 K and T(MF)(c)=0.9 K. It is demonstrated that SC does not yield any trace of gap opening in low-lying excitations below T(onset)(c)=2 K, but T(MF)(c)=0.9 K, followed by a T(1)T=const law. These results point to the unconventional characteristics of SC coexisting with AFM. We highlight that both of the results deserve theoretical work on the gapless nature in the low-lying excitation spectrum due to the coexistence of AFM and SC and the lack of the mean-field regime below T(onset)(c)=2 K.