An Analysis of Delayed Bleeding in Cases of Colorectal Endoscopic Submucosal Dissection Due to Types of Direct Oral Anticoagulants in Japan

BACKGROUND & AIMS

Reported rates of delayed bleeding (DB) after endoscopic resection using direct oral anticoagulants (DOACs) are high and heterogeneous. This large-scale multicenter study analyzed cases of DB after colorectal endoscopic submucosal dissection related to various types of DOACs in Japan (the ABCD-J study) with those associated with warfarin.

METHODS

We retrospectively reviewed 1019 lesions in patients treated with DOACs and 459 lesions in patients treated with warfarin among 34,455 endoscopic submucosal dissection cases from 47 Japanese institutions between 2012 and 2021. The DB rate (DBR) with each DOAC was compared with that with warfarin. Risk factors for DB in patients treated with DOACs or warfarin were also investigated.

RESULTS

The mean tumor sizes in the DOAC and warfarin groups were 29.6 ± 14.0 and 30.3 ± 16.4 mm, respectively. In the DOAC group, the DBR with dabigatran (18.26%) was significantly higher than that with apixaban (10.08%, P = .029), edoxaban (7.73%, P = .001), and rivaroxaban (7.21%, P < .001). Only rivaroxaban showed a significantly lower DBR than warfarin (11.76%, P = .033). In the multivariate analysis, heparin bridging therapy (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.27-3.73, P = .005), rectal location (2.01, 1.28-3.16, P = .002), and procedure time ≥55 minutes (2.43, 1.49-3.95, P < .001) were significant risk factors for DB in the DOAC group. The DB risk in the DOAC group (OR, (95% CI)) was 2.13 (1.30-3.50) and 4.53 (2.52-8.15) for 1 and 2 significant risk factors, respectively.

CONCLUSIONS

Dabigatran was associated with a higher DBR than other DOACs, and only rivaroxaban was associated with a significantly lower DBR than warfarin.

Three-dimensional SAFT imaging for anisotropic materials using photoacoustic microscopy

A pulsed laser illuminates a target zone that causes rapid thermoelastic expansion, generating broadband high-frequency ultrasonic wave (photoacoustic wave, PA wave). We developed a PA microscopy (PAM) with a confocal area of laser and ultrasonic wave for applications in nondestructive testing (NDT). The synthetic aperture focusing technique (SAFT) is applied in the PAM for the three-dimensional (3D) imaging of interior flaws. Here, we report proof-of-concept experiments for the NDT of a subsurface flaw in a thin laminar material. Graphical abstract (a) shows a specimen of carbon-fiber-reinforced plastic (CFRP) with an artificial delamination. Here, it should be noted that the group velocity varies directionally due to the strong anisotropy of the CFRP specimen (see Graphical abstract (b)). By considering the group velocity distribution in the SAFT, the shape and location of the subsurface delamination were accurately estimated as shown in Graphical abstract (c). Coating the surface of the CFRP specimen with a light-absorbent material improved the amplitude of the PA wave. This finding showed that the signal-to-noise ratio of the waves scattered from the flaws can be improved.

Survey of Two New (Kai 1 and Kai 2) and Other Blood Groups in Dogs of North America

Background

Based upon serology, >10 canine blood group systems have been reported.

Objective

We surveyed dogs for dog erythrocyte antigen (DEA) 1 and 2 new blood types (Kai 1 and Kai 2), and some samples also were screened for Dal and DEA 3, 4, and 7.

Methods

Blood samples provided by owners, breeders, animal blood banks, and clinical laboratories were typed for DEA 1 by an immunochromatographic strip technique with a monoclonal antibody and analysis of band intensity. Both new antigens, the Dal and other DEAs (except DEA 7 by tube method), were assessed by a gel column method with either monoclonal or polyclonal antibodies. The same gel column method was applied for alloantibody detection.

Results

Of 503 dogs typed, 59.6% were DEA 1+ with 4% weakly, 10% moderately, and 45.6% strongly DEA 1+. Regarding Kai 1 and Kai 2, 94% were Kai 1+/Kai 2‐, 5% were Kai 1‐/Kai 2‐ and 1% were Kai 1‐/Kai 2+, but none were Kai 1+/Kai 2+. There was no relationship between Kai 1/Kai 2 and other blood types tested. Plasma from DEA 1‐, Kai 1‐, Kai 2‐ dogs, or some combination of these contained no detectable alloantibodies against DEA 1 and Kai 1 or Kai, respectively.

Conclusions and Clinical Importance

The new blood types, called Kai 1 and Kai 2, are unrelated to DEA 1, 3, 4, and 7 and Dal. Kai 1+/Kai 2‐ dogs were most commonly found in North America. The clinical relevance of Kai 1 and Kai 2 in canine transfusion medicine still needs to be elucidated.

Molecular prevalence of multiple genetic disorders in Border collies in Japan and recommendations for genetic counselling

Reproductive management is necessary to prevent deleterious genetic disorders in purebred dogs, but comprehensive studies aimed at prevention of multiple underlying genetic disorders in a single breed have not been performed. The aims of this study were to examine mutant allele frequencies associated with multiple genetic disorders, using Border collies as a representative breed, and to make recommendations for prevention of the disorders. Genotyping of known mutations associated with seven recessive genetic disorders was performed using PCR assays. More than half (56%) of the Border collies had no mutant alleles associated with any of the seven disorders, suggesting that these disorders can be removed from the population over several generations. Since frequencies of each mutant allele differed among disorders, reproductive management should be performed after the establishment of prevention schemes that are appropriate for each disorder, the type and specificity of genetic test available, and the effective population size in each breeding colony.

Expression of Autophagy-Related Proteins in the Spinal Cord of Pembroke Welsh Corgi Dogs With Canine Degenerative Myelopathy

Canine degenerative myelopathy (DM) is a progressive neurodegenerative disease frequently found in Pembroke Welsh Corgi (PWC) dogs, and it has clinical and pathologic similarities to human amyotrophic lateral sclerosis. Autophagy is a major intracellular protein degradation system. Abnormalities of autophagy—resulting in cell death through mechanisms called type II programmed cell death—have recently been reported to occur in various neurodegenerative diseases, including amyotrophic lateral sclerosis. Thus, the distribution and expression levels of proteins involved in autophagy were examined in the spinal cords of 8 PWC dogs suffering from DM with superoxide dismutase mutation, 5 non-DM PWC dogs, and 6 Beagle dogs without neurologic signs. There was no significant difference in the ratio of neurons with microtubule-associated protein light chain 3 (LC3)–positive somata relative to those that were LC3 negative among the 3 groups, whereas the number of LC3-positive neurites was significantly increased in DM dogs. Punctate LC3 immunoreactivity did not colocalize with a lysosome marker, LAMP2 (lysosome-associated membrane protein 2). NBR1 (neighbor of BRCA gene 1) was localized mostly in reactive astrocytes, whereas there were p62 (p62/A170/SQSTM1)–positive foci in the neuropil of the spinal cord of DM dogs. Western blotting revealed in DM dogs the decreased expression of Beclin1 and Atg16 L, which are molecules involved in formation of the isolation membrane. These findings suggest that altered autophagosome degradation may result in LC3 and p62 accumulation in the DM spinal cord, whereas the early stage of membrane formation is likely to be downregulated.

Feline cystinuria caused by a missense mutation in the SLC3A1 gene

Background

Cystinuria is an inherited metabolic disease that is relatively common in dogs, but rare in cats and is characterized by defective amino acid reabsorption, leading to cystine urolithiasis.

Objectives

The aim of this study was to report on a mutation in a cystinuric cat.

Animals

A male domestic shorthair (DSH) cat with cystine calculi, 11 control cats from Wyoming, and 54 DSH and purebred control cats from elsewhere in the United States.

Methods

Exons of the SLC3A1 gene were sequenced from genomic DNA of the cystinuric cat and a healthy cat. Genetic screening for the discovered polymorphisms was conducted on all cats.

Results

A DSH cat showed stranguria beginning at 2 months of age, and cystine calculi were removed at 4 months of age. The cat was euthanized at 6 months of age because of neurological signs possibly related to arginine deficiency. Twenty‐five SLC3A1 polymorphisms were observed in the sequenced cats when compared to the feline reference sequence. The cystinuric cat was homozygous for 5 exonic and 8 noncoding SLC3A1 polymorphisms, and 1 of them was a unique missense mutation (c.1342C>T). This mutation results in a deleterious amino acid substitution (p.Arg448Trp) of a highly conserved arginine residue in the rBAT protein encoded by the SLC3A1 gene. This mutation was found previously in cystinuric human patients, but was not seen in any other tested cats.

Conclusions and Clinical Importance

This study is the first report of an SLC3A1 mutation causing cystinuria in a cat, and could be used to characterize other cystinuric cats at the molecular level.

Vascular calcification and secondary hyperparathyroidism of severe chronic kidney disease and its relation to serum phosphate and calcium levels

BACKGROUND AND PURPOSE

Various complications consequent on disordered calcium and phosphate homeostasis occur frequently in chronic kidney disease (CKD) patients. Particularly, vascular calcification has high morbidity and mortality rates. There is a clear need for a better CKD model to examine various aspects of this disordered homeostasis.

EXPERIMENTAL APPROACH

Oral dosing with adenine induced CKD in rats in only 10 days. Serum calcium, phosphate and parathyroid hormone were measured and calcification in aorta was assessed histologically. The effects of varying phosphorus content of diet or treatment with phosphate binders or active vitamin D(3) on these parameters were examined.

KEY RESULTS

After adenine dosing, significant hyperphosphatemia, hypocalcemia and secondary hyperparathyroidism (2HPT) were observed during the experimental period of 15 weeks. Aortic calcification was detected in only some of the animals even at 15 weeks (approximately 40%). Treatment with vitamin D(3) for 18 days, even at a low dose (100 ng x kg(-1), 3-4 times week(-1), p.o), caused aortic calcification in all animals and increases in serum calcium levels up to the normal range. The vitamin D(3)-induced calcification was significantly inhibited by phosphate binders which lowered serum phosphate levels and the calcium x phosphate product, although serum calcium levels were elevated.

CONCLUSIONS

These data suggest that rats dosed orally with adenine provide a more useful model for analysing calcium/phosphate homeostasis in severe CKD. Controlling serum calcium/phosphate levels with phosphate binders may be better than vitamin D(3) treatment in hyperphosphatemia and 2HPT, to avoid vascular calcification.

CLOCK gene T3111C polymorphism is associated with Japanese schizophrenics: a preliminary study

The CLOCK gene has attracted attention due to its influence on the circadian rhythm, as well as its impacts on the dopaminergic system. We conducted a preliminary study to examine whether the T3111C single nucleotide polymorphism of the CLOCK gene is associated with the development of schizophrenia by examining samples from schizophrenics (n=145) and normal controls (n=128). Both genotype and allele frequencies were significantly different between schizophrenics and controls (p=0.022, p=0.015, respectively). Schizophrenics had a significantly higher frequency of the C allele compared to controls (odds ratio 1.76, 95% CI 1.12-2.75). In particular, disorganized and residual type schizophrenics had significantly higher C allele frequencies than controls (p=0.004 and p=0.037, respectively). Our results suggest that the T3111C polymorphism of the CLOCK gene is associated with schizophrenia. It is important to explore the association between CLOCK and dopamine function, and to examine the impact of CLOCK on phenotypes such as symptoms and drug response in patients with schizophrenia.

The Eating Disorder Inventory-2 in Japanese clinical and non-clinical samples: psychometric properties and cross-cultural implications

OBJECTIVE

To determine the usefulness of and cross-cultural differences in the Japanese version of the eating disorder inventory-2 (EDI-2).

METHOD

A Japanese version of the EDI-2 was administered to a consecutive series (1995-2001) of 91 Japanese eating disordered inpatients and 119 matched non-clinical controls. Scores were compared with each other and with those of Canadian data previously reported. Internal consistencies were also examined.

RESULTS

All subscales (except Ascetism) reached sufficient internal consistencies. The patients' mean scores were significantly higher than controls on most subscales. Restricting anorexics (AN-R) scored higher than controls on body dissatisfaction (BD) and Social Insecurity (SI) subscales. Purging bulimics (BN-P) scored higher than controls on most subscales, except for maturity fears (MF) and SI subscales. Scores of binge-eating/purging type anorexics (AN-B/P) were higher than controls on all subscales. AN-B/P and BN-P scored higher than AN-R on bulimia (B) subscale. Comparison with Canadian subjects showed that Japanese control subjects scored significantly higher on the MF, ineffectiveness (I), impulse regulation (IR), SI subscales, and lower on the perfectionism (P) subscale.

DISCUSSION

The EDI-2 is useful and reliable in understanding Japanese clinical and non-clinical samples. High MF and low P subscales in our samples confirm previous findings in Chinese samples suggesting meaningful cultural differences in the emphasis placed on family bonds and individual accomplishments. In addition, high I, IR, and SI scores in Japanese non-clinical samples may reflect recent problems in Japanese culture.

Alterations of ubiquitin immunoreactivity in the hippocampal formation after perforant pathway lesion

Immunohistochemical techniques were employed to examine the changes in free ubiquitin within the hippocampus 1, 3, 7, 14, and 30 days after a unilateral perforant pathway lesion occurred in the rat brain. Immunoreactivity for ubiquitin was remarkably decreased in the cell body and proximal dendrites of neurons throughout the hippocampus ipsilateral to the lesion at 1 day post-lesion. At 3 days post-lesion, ubiquitin immunoreactivity was recovered in interneurons in the whole hippocampus as well as in mossy cells in the hilar region, although granule cells in the dentate gyrus and pyramidal cells in the CA1 subfield remained unlabeled, and pyramidal cells in the CA3 subfield demonstrated only weak immunoreactivity. In addition, we observed an increase in ubiquitin immunolabeling of the hilar neuropil ipsilateral to the lesion at 1 and 3 days post-lesion, and a decrease in immunolabeling in the inner portion of the molecular layer at 3 days post-lesion. All these alterations were transient, and by 7 days post-lesion, ubiquitin immunoreactivity was indistinguishable in the hippocampus ipsilateral to the lesion, compared to the controls. Immunoblot analysis also revealed a decrease in the amount of ubiquitin in the hippocampus ipsilateral to the lesion 1 and 3 days post-lesion. These data suggest that deafferentation of the perforant pathway results in transient reduction in free ubiquitin of the hippocampus, and that the ubiquitin system is involved in hippocampal plasticity following perforant lesions.

Role of endogenous PACAP in catecholamine secretion from the rat adrenal gland

We elucidated the contribution of endogenous pituitary adenylate cyclase-activating polypeptide (PACAP) to neurally evoked catecholamine secretion from the isolated perfused rat adrenal gland. Infusion of PACAP (100 nM) increased adrenal epinephrine and norepinephrine output. The PACAP-induced catecholamine output responses were inhibited by the PACAP type I receptor antagonist PACAP- (6-38) (30-3,000 nM) but were resistant to the PACAP type II receptor antagonist [Lys1,Pro2,5,Ara3,4,Tyr6]-vasoactive intestinal peptide (LPAT-VIP; 30-3,000 nM). Transmural electrical stimulation (ES; 1-10 Hz) or infusion of ACh (6-200 nM) increased adrenal epinephrine and norepinephrine output. PACAP-(6-38) (3,000 nM), but not LPAT-VIP, also inhibited the ES-induced catecholamine output responses. However, PACAP-(6-38) did not affect the ACh-induced catecholamine output responses. PACAP at low concentrations (0.3-3 nM), which had no influence on catecholamine output, enhanced the ACh-induced catecholamine output responses, but not the ES-induced catecholamine output responses. These results suggest that PACAP is released from the nerve endings to facilitate the neurally evoked catecholamine secretion through PACAP type I receptors in the rat adrenal gland.

NAD/NADH models with axial/central chiralities: superiority of the quinoline ring system

Precursors of NAD model compounds 1c and 3a,b were successfully resolved into their atropisomers with respect to carbamoyl rotation. Atropisomers of quinoline derivatives are much more stable than pyridine derivatives as determined by cyclic voltammetry and X-ray crystallography. The 1,4-reduction of NAD model compound 4 was successfully achieved, affording novel NADH model compound 5. The rotational properties of the side chain of 5 were investigated by means of dynamic NMR. The rotational rate and syn/anti ratio, which indicate the orientation between carbonyl oxygen and hydrogen at the 4-position, are significantly affected by addition of magnesium ion. In the rotational transition state, the double-bond character of the C(carbonyl)-N(amide) bond is disrupted judging from the activation parameters. The oxidation of chiral 5 with p-benzoquinone in the presence of magnesium ion catalyst gave predominantly one enantiomer of 4. On the other hand, oxidation of 5 with p-chloranil (tetrachloro-p-benzoquinone) in the absence of magnesium ions affords the opposite enantiomer of 4 as the major product. The product enantiomer ratio is parallel to the syn/anti ratio in the starting material, indicating the importance of ground state conformation to stereochemistry of the reaction.

Age-related loss of the AMPA receptor subunits GluR2/3 in the human nucleus basalis of Meynert

Magnocellular cholinergic neurons in the basal forebrain have long been recognized as vulnerable to the pathology of Alzheimer's disease. Despite numerous anatomical, pharmacological, behavioral, and physiological investigations of these neurons the cellular mechanism that underlines their selective vulnerability remains unclear. As part of an ongoing investigation into the molecular mechanism(s) underlying neuronal vulnerability in Alzheimer's disease and normal aging, we employed immunocytochemical techniques and examined the cellular localization of the alpha-amino-3-hydroxy-5-methyl-4-isoaxolepropionate (AMPA) glutamate receptor subunits GluR1 and GluR2/3 in the basal forebrain of eight nondemented elderly human subjects (66-102 years). For each case we observed GluR1-positive magnocellular cells darkly labeled within all main divisions of the basal forebrain (Ch1-Ch4). Double-labeling immunohistochemical techniques confirmed that the overwhelming majority (94%) of these neurons were also positive for the p75NGFr antibody, thus substantiating the cholinergic nature of these neurons. In contrast, GluR2/3 immunolabeling upon magnocellular neurons was relatively faint or nonexistent. The latter observations were most apparent in cases of advanced age and in the posterior part of the nucleus basalis of Meynert (NBM) (i.e., Ch4). In contrast, in adjacent structures (e.g., globus pallidus), a number of robustly labeled GluR2/3-positive cells were observed. In addition to the eight elderly subjects, we examined GluR1 and GluR2/3 immunostaining in the NBM of five younger cases, 5, 33, 36, 47, and 48 years of age. Although practical considerations limited our observations to the Ch4 region, we observed both GluR1 and GluR2/3 labeling upon NBM neurons in this latter region. On average, the distribution of labeled cells and intensity of immunoreaction were comparable between GluR1 and GluR2/3. The presence of GluR2/3- and GluR1-labeled neurons in the Ch4 region of younger cases but primarily GluR1 in cases of advanced age suggests an age-related decrease in GluR2/3. Functionally, the loss of GluR2 from the AMPA receptor complex results in ion channels highly permeable to Ca(2+). These alterations in cation permeability of the AMPA receptor together with the occurrence of a number of other intrinsic and extrinsic events (i.e., decrease Ca(2+)-binding protein) likely contribute to the vulnerability of these neurons in aging and in AD.

A case of temporal lobe epilepsy with improvement of clinical symptoms and single photon emission computed tomography findings after treatment with clonazepam

A 26-year-old female presented psychomotor seizures, deja vu and amnestic syndrome after meningitis at the age of 14 years. Repeated electroencephalograms (EEG) demonstrated occasional spikes localized in the right temporal region in addition to a considerable amount of theta waves mainly in the right fronto-temporal region. Single photon emission computed tomography (SPECT) showed a marked hypoperfusion corresponding to the region in which the EEG showed abnormal findings, although magnetic resonance imaging (MRI) demonstrated no abnormal findings associated with the clinical features. Treatment with clonazepam in addition to sodium valproate resulted in a remarkable improvement of clinical symptoms (i.e. psychomotor seizures and deja vu), as well as of the EEG and SPECT findings. The present study suggests that SPECT is a useful method not only to determine the localization of regions associated with temporal lobe epilepsy but also to evaluate the effect of treatment in temporal lobe epilepsy.

Immunohistochemical study of the hnRNP A2 and B1 in the rat forebrain

Immunohistochemical techniques were employed to examine the distribution of RNA-binding proteins A2 and B1 in the rat forebrain. Intense A2 and B1 immunolabeling were observed in the nucleoplasm of the neurons in the cerebral cortices, hippocampal formation, olfactory regions, caudate-putamen as well as the supraoptic nucleus of hypothalamus. In contrast, within the bed nucleus of the stria terminalis, as well as the medial and lateral habenular nucleus of thalamus, immunoreactivity for both proteins was weak. Within the globus pallidus and thalamic nucleus immunoreactivity for A2 was hardly detectable despite of intense B1 immunolabeling, while within the endopiriform nucleus and lateral and basolateral nucleus of amygdala intensity of B1 immunolabeling was relatively weak compared to A2. Our study suggests that the distribution of A2 and B1 are not constant throughout the forebrain and this diversity may reflect the post-transcriptional regulation of cell-specific gene expression of neuronal cells.

Immunohistochemical localization of gamma-aminobutyric acid(B) receptor in the hippocampus of subjects with schizophrenia

Recent studies have demonstrated the involvements of gamma-aminobutyric acid (GABA) neurotransmitter systems in the schizophrenic brain. In order to further elucidate the alterations of this system in schizophrenia, we employed immunohistochemical techniques and examined the expression and anatomical distribution of the GABA(B) receptor in the hippocampus of five subjects with schizophrenia and three age-matched controls. In the control hippocampus, the most intense immunoreactivity was observed in the soma and processes of multipolar interneurons throughout the hippocampus. Pyramidal cells too were intensely labeled in their soma and proximal portion of dendrites, although the labeling intensity was varied in each subregion. For example, in the CA1 subfield, the labeling intensity of pyramidal cells was much less intense than that in the CA3 and CA2 subfields. In the subjects with schizophrenia, GABA(B) immunoreactivity was markedly reduced in granule cells as well as in pyramidal cells throughout the CA fields. In interneurons, GABA(B) labeling was relatively preserved compared to that in pyramidal cells. Our findings suggest that in the hippocampus of schizophrenic patients the expression of the GABA(B) receptor is reduced, and raise the possibility that this reduction contributes to the pathophysiological process in the schizophrenic brain.

Distribution of glutamate receptor subunit NMDAR1 in the hippocampus of normal elderly and patients with Alzheimer's disease

Immunocytochemical techniques were employed to study the distribution and cytological features of NMDAR1-immunoreactive elements in the human hippocampal formation. Subjects with Alzheimer's disease (AD), presenting with a wide range of neuropathology and classified into six Braak stage (I-VI), and nondemented age-matched controls were examined. In control cases, the most intense NMDAR1 immunoreactivity was observed within the soma and dendrites of granule cells in the dentate gyrus and pyramidal neurons in Ammon's horn. Whereas small variations in the pattern of immunoreactivity were noted in control cases, AD subjects were characterized with intersubject variability which in most instances correlated with neuropathologic severity. For example, AD cases, particularly those with mild/modest pathology (Braak I-III), were indistinguishable from controls in the overall pattern of immunolabeling. In contrast, in those more severe AD cases (Braak IV-VI) the intensity of immunolabeling within the CA fields was greater than observed in controls and those with mild AD pathology. In addition, in pathologically severe cases numerous NMDAR1-positive pyramidal neurons were characterized by unique morphologic features including long and often tortuous apical dendrites. These latter findings were most prevalent in the CA1 region and subiculum. In contrast to the marked increase in immunolabeling in the CA fields, in the dentate gyrus we observed a reduction in NMDAR1 labeling particularly within the outer molecular layer (i.e., termination zone of the perforant pathway). This latter region was also the site of a number of NMDAR1-labeled plaques. Notably, the overall pattern of NMDAR1 immunoreactivity is distinct from that observed with antibodies against AMPA receptor subunits and suggests a differential role of various inotropic glutamate receptors in hippocampal plasticity in AD.

Some physiological and pharmacological properties of slow depolarization of substantia gelatinosa neurons by repetitive stimulation of C-fibers of dorsal root in adult rat spinal cord slices with dorsal root attached

Transverse slices of the spinal cord with dorsal root attached were prepared from adult rats and used to record the response of the spinal substantia gelatinosa neurons evoked by repetitive stimulation of the dorsal root with a whole cell patch clamp method. The repetitive stimulation of 10 trains (20 pulses at 100 Hz/train) with an intensity necessary to activate C-fibers, but not A-fibers alone, evoked slow depolarization (SD) during it and the SD disappeared within 1 min after the termination of it. The SD was completely inhibited by 500 nM of tetrodotoxin (TTX), but not significantly changed by 50 nM of TTX, nor 20 microM CNQX + 50 microM AP5, nor 1 microM CP-99994. DAMGO inhibited the SD in a concentration dependent manner (10 nM-1 microM), but 1 microM DPDPE and 1 microM U-50488H did not. The inhibitory effect of DAMGO (1 microM) was reversed by naloxone (1 microM). These results suggest that the SD of substantia gelatinosa neurons evoked by repetitive stimulation of C-fibers of the dorsal root is an event relevant to nociception in the spinal dorsal horn.

A case of psychotic disorder associated with a right temporal lesion: a special reference to magnetic resonance imaging and single photon emission computed tomography findings

A case of psychotic disorder with a right temporal lesion was reported. The patient, a 19 year old male, who underwent a brain surgery to remove the trigeminal Schwannoma, occupying from the right cerebellopontine angle to the right middle cranial fossa. One year postoperatively, he presented with a psychotic disorder, including auditory hallucinations, delusions of persecution and reference, thought hearing, thought insertion and passive experiences. T1-weighted images on magnetic resonance imaging (MRI) demonstrated a low intensity signal area in the right temporal cortex and white matter. T2-weighted images demonstrated a high intensity signal within the same region. Single photon emission computed tomograghy (SPECT) demonstrated a severe low perfusion corresponding to the region in which the MRI demonstrated the abnormalities. The clinical and neuroimaging studies of this case suggest that psychotic disorder may occur in association with a right temporal lesion and MRI and SPECT are useful to evaluate an organic basis for the psychotic disorder.

Distribution of orexin neurons in the adult rat brain

Orexin (ORX)-A and -B are recently identified neuropeptides, which are specifically localized in neurons within and around the lateral hypothalamic area (LHA) and dorsomedial hypothalamic nucleus (DMH), the regions classically implicated in feeding behavior. Here, we report a further study of the distribution of ORX-containing neurons in the adult rat brain to provide a general overview of the ORX neuronal system. Immunohistochemical study using anti-ORX antiserum showed ORX-immunoreactive (ir) neurons specifically localized within the hypothalamus, including the perifornical nucleus, LHA, DMH, and posterior hypothalamic area. ORX-ir axons and their varicose terminals showed a widespread distribution throughout the adult rat brain. ORX-ir nerve terminals were observed throughout the hypothalamus, including the arcuate nucleus and paraventricular hypothalamic nucleus, regions implicated in the regulation of feeding behavior. We also observed strong staining of ORX-ir varicose terminals in areas outside the hypothalamus, including the cerebral cortex, medial groups of the thalamus, circumventricular organs (subfornical organ and area postrema), limbic system (hippocampus, amygdala, and indusium griseum), and brain stem (locus coeruleus and raphe nuclei). These results indicate that the ORX system provides a link between the hypothalamus and other brain regions, and that ORX-containing LHA and DMH neurons play important roles in integrating the complex physiology underlying feeding behavior.

An autopsy case of myotonic dystrophy with mental disorders and various neuropathologic features

An autopsy case of myotonic dystrophy (MD) is reported. The patient was a 58-year-old male. He presented with muscular weakness and muscular atrophy at the age of 33 and was diagnosed as having MD from myotonic symptoms (i.e. percussion and grip myotonia) at 49 years old. Mental disorders including a delusional hallucinatory state, mental slowness, indifference, and lack of spontaneity as well as visual cognitive impairments were noted at the age of 55. He showed Parkinsonism and died of septic shock. T2-weighted magnetic resonance imaging demonstrated diffuse cortical atrophy with a marked frontal atrophy and high-intensity signals in the white matter. Single photon emission computed tomography demonstrated hypoperfusion in the frontal cortex. Neuropathologic observation revealed neuronal loss in the superficial layer of the frontal and parietal cortices and extensive neuronal loss in the occipital cortex, intracytoplasmic inclusion body in the nerve cell of the medial thalamic nuclei, neuronal loss and presence of Lewy bodies in the substantia nigra and locus ceruleus corresponding to the pathologic features of Parkinson's disease, as well as abnormalities of myelin in the white matter. The present case suggests that in MD brain, various neuropathologic changes may occur and they contribute to the mental disorders.

Immunohistochemical study of GABAA receptor alpha1 subunit in the hippocampal formation of aged brains with Alzheimer-related neuropathologic changes

Immunocytochemical techniques were employed to examine the distribution of the gamma-aminobutyric acid (GABA)A receptor alpha1 subunit within the hippocampus of 19 elderly subjects with Alzheimer-related neuropathologic changes. In mild cases (i.e., Braak stages I and II), the most intense neuropil immunolabeling was observed in the molecular layer of the dentate gyrus, the stratum pyramidale of the CA1 subregion and subiculum, while the weakest labeling was observed in the CA3 subfield. In CA4 region, the proximal dendrites and cell bodies of mossy cells were intensely alpha1 positive. Throughout the hippocampus, we observed a number of alpha1 labeled interneurons. These cells consisted of both large and small multipolar cells as well as small bipolar neurons. In moderate cases (i.e., Braak stages III and IV), the pattern and intensity of alpha1 immunolabeling appeared indistinguishable from mild cases. In severe cases (i.e., Braak stages V and VI), we observed a marked decrease in neuropil immunolabeling within the CA2, CA1 subregions and prosubiculum, while the labeling of the molecular layer of the dentate gyrus, subiculum proper and presubiculum was indistinguishable from mild and moderate cases. These data together with our previous immunocytochemical study in which we demonstrated a marked preservation of the GABAA receptor subunit beta2/3 suggest that responses of selected GABAA receptor subunits to AD pathology are variable with the alpha1 subunit displaying a high degree of vulnerability.

GABAA receptor beta 2 and beta 3 subunits mRNA in the hippocampal formation of aged human brain with Alzheimer-related neuropathology

Our work on the role of glutamate in Alzheimer's disease (AD)-related neuronal vulnerability and death provided significant insight into the potential contribution of the gamma-aminobutyric acid (GABA) neurotransmitter system as it participates in countering the neurotoxic effects of excessive glutamate receptor stimulation. Our previous studies demonstrate that beta2/3 GABAA receptor subunit immunoreactivity is relatively well preserved in hippocampi with AD pathology. To further elucidate the molecular basis for this observation, we employed in situ hybridization histochemistry to examine the levels of beta2 and beta3 receptor subunit mRNAs in the hippocampus of 19 elderly subjects presenting with a broad range of pathologic severity (i.e., Braak stage I-VI). Semi-quantitative analysis with film autoradiograms revealed that beta2 mRNA signal was highest in the granule cell layer, CA2 and CA1 subfields, while beta3 mRNA hybridization was highest in the granule cell layer, followed by CA2>/=CA3>/=CA1 regions. No significant difference in beta2 mRNA expression was detected among the pathologically mild, moderate or severe groups. In contrast, levels of beta3 mRNA in the pathologically severe group was significantly decreased compared to the mild group within all subregions examined except CA4. Our data suggest that alterations in the expression of GABAA receptor subunits in the AD hippocampus differ between specific receptor subunits with the amount of beta2 mRNA being relatively well-preserved, while beta3 mRNA levels were decreased.

Alterations of GABA(A)beta2/3 immunoreactivity in the dentate gyrus after perforant pathway lesion

Immunocytochemical techniques were employed to examine the changes in the GABA receptor subunits beta2/3 within the dentate gyrus of the rat brain 1, 3, 7, 14, 30 and 90 days after a unilateral perforant pathway lesion. Three days post-lesion we observed a decrease in beta2/3 immunolabeling in the inner molecular layer of the dentate gyrus followed by a comparable decrease in the outer molecular layer 7 days post-lesion. These decreases were transient; 30 and 90 days post-lesion, beta2/3 immunolabeling appeared similar to controls in the inner portion of the molecular layer, while in the outer region the labeling was increased. In this latter region we also observed a dense band of AChE fibers. Following survival times of 3 days we observed a diffuse staining of the neuropil in the hilar region, and a dense amorphous accumulation of peroxidase reaction product in the polymorphic region. These responses were transient and by 14 days the hilar/polymorphic region appeared indistinguishable from controls. These data suggest a unique pattern of immunoabeling in the molecular and polymorphic region in response to perforant pathway lesion. A putative explanation for this response is discussed.

Immunohistochemical study of GABA(A) receptor beta2/3 subunits in the hippocampal formation of aged brains with Alzheimer-related neuropathologic changes

In AD, it is hypothesized that one factor contributing to the vulnerability of neurons is a delicate balance of excitatory and inhibitory inputs. To examine this hypothesis we have initiated a number of studies examining the role of the excitatory neurotransmitter glutamate and the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the neurodegeneration of AD. As an initial investigation into the GABAergic system in AD, we employed immunocytochemical techniques and examined the distribution and density of the GABAA receptor subunits beta2/3 within the hippocampus of 13 subjects with a clinical diagnosis of AD and 6 nondemented elderly subjects. Collectively, these 19 subjects presented with a broad range of pathologic severity (i.e., Braak stages I-VI). Density measurements of nine hippocampal regions demonstrated highest levels of beta2/3 immunolabeling in the inner molecular layer of the dentate gyrus > CA1 > CA2, while the lowest levels were found in the granular layer of the dentate gyrus < or = CA4 < CA3 field. Despite these regional variations no significant difference in the mean density of beta2/3 immunolabeling was observed when comparing the pathologically mild (stages I and II), moderate (stages III and IV), and severe (stages V and VI) groups. These data suggest that in the hippocampus receptor subunits associated with GABAergic neurotransmission are relatively maintained even until the terminal stages of the disease.

Alterations of AMPA-selected glutamate subtype immunoreactivity in the dentate gyrus after perforant pathway lesion

Immunocytochemical techniques were employed to examine the changes in immunolabeling of the alpha-amino-3-hydroxy-5-methyl-4-isoaxolepropionate (AMPA) receptor subunits GluR1 and GluR2/3 within the dentate gyrus 1, 3, 7, 14, 30, and 90 days after a unilateral perforant pathway lesion in the rat brain. Completeness of the lesion was confirmed following examination of Nissl-stained tissue sections at all times post-lesion and acetylcholinesterase (AChE)-stained sections 14, 30 and 90 days post-lesion, the latter providing evidence of compensatory sprouting of cholinergic fibers in the outer molecular layer of the dentate gyrus. Compared to the non-lesioned hippocampus there was no difference in the staining pattern of AMPA receptor subunits in the dentate gyrus of the deafferented hippocampus 1, 3, 7 and 14 days following lesioning of the perforant pathway. In contrast, 30 and 90 days post-lesion, GluR1 immunolabeling was increased in the outer molecular layer of the dentate gyrus (i.e., deafferented zone) ipsilateral to lesion. Likewise, GluR2/3 immunolabeling was increased within the same region although the intensity of the response was less than that which was observed for GluR1. These data suggest that the loss of the perforant pathway fibers results in a compensatory increase in GluR1 and to a lesser extent GluR2/3 immunolabeling of the outer molecular layer at 30 and 90 days post-lesion and further suggest that AMPA receptor subunits play a role in perforant pathway signal transduction.

The loss of GluR2(3) immunoreactivity precedes neurofibrillary tangle formation in the entorhinal cortex and hippocampus of Alzheimer brains

Double-immunolabeling techniques were employed to examine the distribution of GluR2(3) subunits and markers of early cytoskeletal changes (mab MC1) within the entorhinal cortex (EC) and hippocampus of cases with varying degrees of Alzheimer disease (AD) pathology (stages I-VI by Braak and Braak). In addition near-adjacent tissue sections were double-immunolabeled using antibodies against GluR2(3) and a marker of normal neuronal cytoskeleton (MAP2). In those cases classified as stages I-II, most layer II neurons of the EC and pyramidal neurons in the CA1/subiculum were double-labeled with GluR2(3) and MAP2. An occasional MC1-labeled cell was observed, yet in no instance were these neurons double-labeled with GluR2(3). In cases with moderate AD pathology (stages III-IV), layer II of the EC and CA1/subiculum were characterized by a substantial loss of GluR2(3)-labeled neurons, while many were still immunoreactive to MAP2. Notably, the loss of GluR2(3) immunolabeling was accompanied by an increasing number of MC1-positive neurons. In no instance were GluR2(3) and MC1 co-localized within the same neuron. In cases with severe AD pathology (stages V-VI), the EC and CA1/subiculum were almost completely devoid of GluR2(3)-positive neurons. MAP2-labeled neurons also were reduced in number. In contrast, both regions contained an abundance of MC1-positive cells. That GluR2(3) and MC1 are not observed in the same neuron, together with the observation that the number of GluR2(3)-labeled neurons decreases as the number of MC1-positive cells increases, suggest that a loss of GluR2(3) immunolabeling precedes the appearance of MC1 immunolabeling.

Oxidative stress on mitochondria and cell membrane of cultured rat hepatocytes and perfused liver exposed to ethanol

BACKGROUND & AIMS

The precise pathogenic significance of oxidative injury in the evolution of alcohol-induced liver disease is still obscure. The present report was designed to investigate whether ethanol alters the production of active oxidants and biological activities of hepatocytes.

METHODS

The following parameters in rat hepatocytes were investigated by using fluorescence probes in vitro and ex vivo: (1) mitochondrial membrane potential and membrane permeability transition, (2) oxygen radicals generation, (3) membrane barrier function, and (4) glutathione level.

RESULTS

Ethanol (50 mmol/L) increased oxidative stress in hepatocytes and subsequently induced an increased mitochondrial permeability transition and a decreased membrane potential. These ethanol-induced alterations were attenuated by an inhibitor of alcohol dehydrogenase and an intracellular oxidant scavenger, whereas they were enhanced by diethyl maleic acid, a glutathione depletor. Ethanol plus diethyl maleic acid but not ethanol alone increased the number of hepatocytes with membrane barrier dysfunction. A continuous infusion of ethanol (50 mmol/L) increased oxidative stress and decreased mitochondrial membrane potential in the pericentral area of isolated perfused rat liver.

CONCLUSIONS

Active oxidants generated during ethanol metabolism increase mitochondrial permeability transition and modulate mitochondrial energy synthesis in hepatocytes. Reduction of glutathione level enhances mitochondrial dysfunction and impairs membrane barrier function of hepatocytes.

A neuropathologic study of long-term, Economo-type postencephalitic parkinsonism with a prolonged clinical course

In this report, the neuropathologic features of five autopsied cases of postencephalitic parkinsonism of the Economo-type (PEPE) with a mean age of 66.6 years and a mean duration of the illness of 53.6 years are described. All five patients had presented with personality changes and severe parkinsonism. In addition, four patients had also had ocular symptoms. A pronounced chronic progression of the symptoms characterized all five cases. Active degenerating lesions were found in the substantia nigra (patients 3, 4 and 5) and the oculomotor nucleus (patient 5) which might explain the clinical observation of chronic active disease in these patients. We found that the intraneuronal neurofibrillary tangles (NFT) were immunoreactive to paired helical filaments (PHF), tau and ubiquitin; but ghost tangles demonstrated immunoreactivity only to glial fibrillary acid protein (GFAP). The ghost tangles consisted of dispersed bundles of abnormal tubules, and electron-dense glial filaments would surround and occasionally invade the ghost tangles. The present study suggests that NFT in PEPE are similar in their immunohistochemistry and ultrastructure to those observed in the case of Alzheimer-type dementia.

A clinical case of neuro-Behçet syndrome without mucocutaneo-ocular symptoms: relationship with brain stem encephalitis

The case of a 50 year old man with personality changes, dementia, and brain stem symptoms is presented. Magnetic resonance imaging (MRI) disclosed high signal areas mainly in the brain stem. Both a positive skin prick test and an HLA-B51 were demonstrated. These clinical findings were suggestive of neuro-Behçet syndrome, although there were no mucocutaneo-ocular symptoms characteristically associated with this disease. The relationship between neuro-Behçet syndrome and brain stem encephalitis, including a discrimination from multiple sclerosis, is discussed.

Patch sensor detection of glutamate release evoked by a single electrical shock

We tried to detect minimal stimulation-induced glutamate overflow from the surface of a hippocampal slice using an outside-out patch electrode excised from pyramidal cell membranes. The amplitude of the stimulation-induced patch current was dependent on the distance between the slice surface and the tip of patch sensor. The current-voltage relations of the stimulation-induced patch current were similar to those of the current evoked puff by application of L-glutamate to the patch. This indicates that the stimulation-induced patch current was produced by glutamate released from presynaptic terminals, and thus this technique may be useful in the study of transmitter release evoked by minimal electrical stimulation in brain slices.

CT, MR, and SPECT findings in a general paresis

CNS changes in a case with general paresis were investigated by X-ray computed tomography (CT), Magnetic resonance (MR), and single photon emission computed tomography (SPECT). CT and MR showed a mild degree of diffuse cortical atrophy and the dilatation of lateral ventricles with no signs of ischemic lesions or inflammations. On the other hand, SPECT using 123I-N-isopropyl-p-iodoamphetamine (123I-IMP demonstrated marked reduction of the cerebral blood flow especially in the bilateral frontal and temporal cortices. Moreover, the reduction of the blood flow was significantly improved after the antisyphilitic therapy, correlated with the improvement of the mental disorders. These observations suggested that the SPECT is a useful method to evaluate the brain dysfunctions, and to assess the effect of antisyphilitic therapy in the patients with general paresis.

An autopsied case of acute lymphocytic meningoencephalitis with a long clinical course: special reference to CT, MR, SPECT and neuropathological findings

This report describes the clinico-pathological features of acute lymphocytic meningoencephalitis (ALME) of a patient with a long clinical course of 24 months. The patient rapidly developed a confusional state, occasionally with stupor, various involuntary movements and generalized convulsions followed by fever and headache at the age of 29. Clinical symptoms, except fever and convulsions, had not distinctly improved throughout the clinical course, and cortical atrophy on CT and MR gradually progressed. SPECT revealed a low blood perfusion in the cerebral cortices. Neuropathologically, inflammatory findings were very mild, but nerve cells degenerated prominently. From these clinicopathological findings, it is suggested that chronic degenerative changes followed an acute inflammatory phase.

Clinicopathological study on a case of neuro-Behçet's disease: in special reference to MRI, SPECT and neuropathological findings

A case of neuro-Behçet's disease with dementia and personality changes is described with magnetic resonance imaging (MRI), single photon emission tomography (SPECT) and neuropathological findings. MRI disclosed high signal areas in the cerebral white matter and the brain stem. SPECT showed a marked reduction of blood flow in the frontal cortex. Neuropathologically, multifocal necrotizing lesions with perivascular lymphocytic infiltration and glial proliferation were detected mainly in the brain stem, namely the midbrain and the pons. From these findings, it is suggested that mental disorders of neuro-Behçet's disease are related to the secondary dysfunction of the frontal cortex due to the damage of the subcortical structures, mainly the brain stem.

CNS changes in DRPLA with dementia and personality changes: CT, MR and SPECT findings

CNS changes in a case of DRPLA associated with dementia and personality changes were observed by CT, MR and SPECT. Brain CT and MR of the patient revealed progressive cortical atrophy which was recognized in parallel with the clinical course of the progression of dementia and personality changes. SPECT using 123I-iodoamphetamine (IMP) disclosed a diffuse low perfusion of the cerebral cortex, especially in the frontal and temporal lobes. These findings suggest that the dementia and personality changes in this case might be concerned with a dysfunction of the cerebral cortex.

Eating disorder and schizophrenia

Five cases with eating disorders (one case with anorexia nervosa alone, 4 cases with anorexia nervosa and bulimia nervosa) complicated with schizophrenia and 3 cases of bulimia nervosa complicated with schizophrenia were reported. The eating disorders and schizophrenia were diagnosed according to the diagnostic criteria of DSM-III-R. As to the type of schizophrenia, 4 patients were of an undifferentiated type and 4 cases were of a disorganized type. Regarding the prepsychotic personality, 6 of the 8 cases showed schizothyme personality traits. All the patients showed depressive symptoms which are relatively common in eating disorders. In all the patients, significant social or school life difficulties persisted and a resumption of premorbid functioning was not seen. The possibility of an affinity between anorexia nervosa and schizophrenia was discussed.

CNS changes in neuro-Behçet's disease: CT, MR, and SPECT findings

CNS changes in three cases of neuro-Behçet's disease were observed by computed tomography (CT), magnetic resonance (MR) and single photon emission computed tomography (SPECT). The present study illustrates the reversibility of lesions in the brain stem with MR, while CT failed to show any abnormal findings in the region of the disease. We conclude that MR is a quite useful method to detect lesions in the brain stem and to evaluate the effects of treatment in neuro-Behçet's disease. SPECT is also an important method for the evaluation of dementia recognized in neuro-Behçet's disease.

An autopsy case of mitochondrial encephalomyopathy (MELAS) with special reference to extra-neuromuscular abnormalities

An autopsy case of a 37-year-old man with mitochondrial encephalomyopathy is reported. Ragged-red fibers and crystalline inclusions in mitochondria were revealed by biopsy of the striated muscle of the patient. Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was diagnosed clinically. In addition to severe atrophy and degeneration of the generalized striated muscles and many foci of laminar necrosis of the cerebral cortex, the following abnormalities were observed: 1) hypertrophy of the myocardium, 2) fatty change of the liver, 3) focal sclerosis of the glomeruli and dilatation of the tubules of the kidneys, 4) hyalinous degeneration of the Langerhans' islands of the pancreas and 5) wavy change of the smooth muscle fibers of the muscularis propria of the gastrointestinal tract. We suggest that mitochondrial encephalomyopathy affects various organs and tissues, among which susceptibility of the muscular tissues--skeletal muscle, myocardium and smooth muscle--is high.

An autopsied case of dentatorubropallidoluysian atrophy with atypical pathological features

This is a report of an autopsied case of dentatorubropallidoluysian atrophy (DRPLA) with atypical neuropathological findings. The patients was a 31-year-old female. Her clinical symptoms were epileptic seizures, cerebellar ataxia, choreoathetosis and dementia. A neuropathological examination revealed the fibrillary gliosis in various areas of the CNS and severe degeneration in the cerebellar cortex and nucleus fasciculi dorsalis in addition to a marked degeneration of the dentatorubropallidoluysian systems. The present case is diagnosed neuropathologically as DRPLA associated with the findings of chronic diphenylhydantoin intoxication and epileptic brain damage.