Nested polymerase chain reaction for assessing the clinical course of tuberculous meningitis.

The authors examined the usefulness of nested PCR (N-PCR) to detect Mycobacterium tuberculosis (MTB) DNA in CSF for assessing the clinical course of tuberculous meningitis (TBM). N-PCR successfully detected MTB DNA in all nine CSF samples from patients with suspected TBM. During anti-tuberculosis treatments, N-PCR results converted from positive to negative, correlating with the improvement of the patient's clinical condition.

Surface orientation discrimination activates caudal and anterior intraparietal sulcus in humans: an event-related fMRI study.

Perception of surface orientation is an essential step for the reconstruction of the three-dimensional (3D) structure of an object. Human lesion and functional neuroimaging studies have demonstrated the importance of the parietal lobe in this task. In primate single-unit studies, neurons in the caudal part of the intraparietal sulcus (CIP) were found to be active during the extraction of surface orientation through monocular (two-dimensional) cues such as texture gradients and linear perspective as well as binocular (3D) cues such as disparity gradient and orientation disparity. We used event-related fMRI to study the functional neuroanatomy of surface orientation discrimination using stimuli with monocular depth cues in six volunteers. Both posterior (CIP) and anterior (AIP) areas within the intraparietal sulcus showed a stronger activation during surface orientation as compared with a control (color discrimination) task using identical stimuli. Furthermore, the signal changes in CIP showed a greater performance effect than those in AIP, suggesting that CIP is tightly linked to the discrimination task.

'Iatrogenic' Wernicke's encephalopathy in Japan.

'Iatrogenic' Wernicke's encephalopathy has appeared to occur more frequently in Japan, probably induced by the change of our Japanese national health insurance policy in 1992. We report 4 nonalcoholic patients with such Wernicke's encephalopathy, which occurred during the early postoperative oral food intake period following intravenous nutrition without vitamin supplements. We analyzed the medical records of 4 patients, 3 men and 1 woman, aged between 55 and 71 years, who were admitted to our hospital between 1992 and 1995. Three patients underwent gastrointestinal surgery and 1 suffered chronic pyothorax. We diagnosed our patients as having Wernicke's encephalopathy based on typical neurological abnormalities, in addition to typical cranial magnetic resonance image findings, low serum vitamin B(1) levels, or both. Although all of the patients were treated with vitamin B(1) and showed some improvement, 1 patient developed Korsakoff syndrome, 2 made incomplete neurological recovery, and 1 died. We speculated that the body vitamin B(1) stores had been decreasing in our patients who did not receive any vitamin supplements during intravenous hyperalimentation or hydration. Subsequent administration of high calorie and high carbohydrate oral diets increased the demand for vitamin B(1), further depleting the vitamin stores, thereby causing 'iatrogenic' Wernicke's encephalopathy. The change of our national health insurance policy in 1992 discouraged the routine administration of vitamins, probably causing Wernicke's encephalopathy in our patients.

Acetazolamide reactivity in atherothrombotic, cardioembolic and lacunar infarctions.

Ten cases of atherothrombotic brain infarction, 10 cases of cardioembolic brain infarction, 10 cases of lacunar brain infarction, 10 cases of transient ischemic attack (TIA) and 10 age-matched controls were studied. The cerebral blood flows in the cerebral cortex and cerebral white matter were significantly lower in the atherothrombotic, cardioembolic and lacunar infarction groups than in the TIA and control groups. The acetazolamide reactivity in the cerebral cortex was significantly lower in the atherothrombotic and lacunar infarction groups than in the cardioembolic, TIA and control groups. The rate of association of hypertension was significantly higher in the atherothrombotic, lacunar and TIA groups than in the cardioembolic and control groups. Plasma fibrinopeptide A, platelet factor 4 and beta-thromboglobulin concentrations were higher in the atherothrombotic, cardioembolic and lacunar groups than in the TIA and control groups. The present study suggests that the degree of thrombolysis and platelet activation is less in TIA than in cerebral infarction and that underlying cerebral arteriosclerosis is more severe in atherothrombotic and lacunar infarction than in cardioembolic infarction.

Effect of cilostazol on cerebral blood flows in chronic stage of cerebral circulation.

In order to find out the difference between cilostazol and ticlopidine hydrochloride in the cerebral vasodilating effect in the chronic stage of cerebral infarction, cerebral blood flows were measured while the patients were on ticlopidine hydrochloride and after ticlopidine hydrochloride was switched to cilostazol. Single photon emission computed tomography (SPECT) was performed using Prism 2000XP gamma camera system. Ultrasound examinations of the carotid artery was performed using Ultramark 9. The blood flows in the frontal white matter, temporal cortex and occipital cortex after cilostazol were significantly higher than those before cilostazol. The peak systolic velocity, time-averaged peak velocity and volume flow after cilostazol were significantly higher than those before cilostazol. The total cholesterol, triglyceride and apolipoprotein B concentrations after cilostazol were significantly lower than those before cilostazol. The present study suggests that cilostazol has better influence on cerebral circulation than ticlopidine hydrochloride in the chronic stage of cerebral infarction.

Molecular characterization of Hop latent virus and phylogenetic relationships among viruses closely related to carlaviruses.

The complete nucleotide sequence of the hop latent virus (HpLV) genome was determined. The viral RNA genome is 8,612 nucleotides long, excluding the poly(A) tail, and contains six open reading frames (ORFs), which encode putative proteins of 224-kDa (ORF 1), 25-kDa (ORF 2), 11-kDa (ORF 3), 7-kDa (ORF 4), 34-kDa (ORF 5), and 12-kDa (ORF 6). ORF 5 encodes the coat protein as demonstrated by N-terminal sequencing of three proteolytic peptides derived from the virus particle. The genome organization of HpLV is similar to that of other species in the genus Carlavirus, and the overall sequence of HpLV is more similar to that of Potato virus M than to sequences of other carlaviruses reported to date. The amino acid sequences of the putative methyltransferase, RNA helicase, and RNA-dependent RNA polymerase encoded in ORF 1 and an 'accessory' helicase encoded in ORF 2 of the HpLV genome were compared with those of viruses in the 'tymo' lineage: the genera Carlavirus, Potexvirus, Allexivirus, Foveavirus, Trichovirus, Capillovirus, Vitivirus, and Tymovirus. The phylogenetic relationships among the viruses in these genera are discussed. This is the first molecular characterization of a carlavirus infecting hop plants.

[A case of post-infectious wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) syndrome].

The patient is a 72-year-old man who had tonsillitis and underwent incision on March 6, 1998. He complained headache and nausea from March 10 and double vision from March 12. He was admitted to our hospital on March 14. Neurological examination on March 18 revealed bilateral internuclear ophthalmoplegia with exotropia (WEBINO), bilateral ptosis and disturbance of convergence. Lumbar puncture revealed moderately elevated protein (46 mg/dl) with normal pressure and cells. The T2-weighted images of head MRI showed multiple high intensity lesions in anterior commissure and right pons. After he was treated with methylprednisolone, his headache and ptosis disappeared. The lesion in anterior commissure on MRI disappeared also. But WEBINO remained at the time of discharge. WEBINO syndrome is caused by lesion of pons and midbrain. The most common cause of bilateral internuclear ophthalmoplegia is multiple sclerosis in the European and American countries, but the frequency of vascular origin is higher in Japan than in the European and American countries. All the cases of WEBINO syndrome reported in Japan are vascular origin. This is the first case of WEBINO syndrome not of vascular origin.

Corpus callosum atrophy and cerebral blood flow in chronic alcoholics.

The corpus callosum atrophy and cerebral blood flows were investigated in chronic alcoholics without Marchiafava-Bignami disease. Fifteen cases of chronic alcoholics and 15 age-matched healthy controls were studied. The sagittal plane of magnetic resonance imaging of the head was scanned into a computer and the corpus callosum was measured and the callosal index was calculated. Cerebral blood flows were measured using stable xenon computed tomography (CT) method. Regional cerebral blood flows in the frontal, temporal, parietal and occipital cortex, frontal, temporal and occipital white matter, caudate nucleus, putamen and thalamus were measured. The corpus callosum area, the thickness of the genu, the thickness of the trunk, the thickness of the splenium, and the callosal index were significantly smaller in the chronic alcoholic group than in the healthy control group. Blood flows in the cerebral cortex, thalamus and putamen were significantly lower in the chronic alcoholic group than in the healthy control group. Significant positive correlations were present between the corpus callosum atrophy and the cerebral cortex blood flows. Corpus callosum atrophy and decreased cerebral blood flows may be seen in chronic alcoholics without Marchiafava-Bignami disease.

Single lacunar brain infarction with transient signs versus those with long-lasting signs.

BACKGROUND: In order to find out the difference between single brain lacunar infarctions with transient signs and those with long-lasting signs, cerebral blood flow studies and blood tests were performed. METHODS: Ten cases of single lacunar infarction with transient signs and 10 of single lacunar infarction with long-lasting signs were studied. Subcortical cystic infarctions with a diameter of less than 1.5 cm were defined as lacunar infarction. Episodes lasting less than 24 hours were classified as transient signs and those lasting 24 hours or more as long-lasting signs. MEASUREMENTS: cerebral blood flows were measured using the stable xenon computed tomography method. The regional cerebral blood flows were measured before and 20 minutes after the intravenous injection of 17 mg/kg acetazolamide. Plasma fibrinopeptide A, platelet factor 4 and beta-thromboglobulin concentrations were determined at the Special Reference Laboratories. RESULTS: Blood flows in the cerebral cortex and cerebral white matter contralateral to the lacunar infarction were lower in the group with long-lasting signs than in that with transient signs. Cerebrovascular acetazolamide reactivity in the cerebral cortex and white matter contralateral to the lacunar infarction were lower in the group with long-lasting signs than in that with transient signs. Plasma fibrinopeptide A, platelet factor 4 and beta-thromboglobulin concentrations were higher in the long-lasting signs group than in that with transient signs. CONCLUSIONS: There may be some differences in pathogenesis between single lacunar infarction with transient signs and those with long-lasting signs.

A mixture of synthetic oligonucleotide probes labeled with biotin for the sensitive detection of potato spindle tuber viroid.

Five kinds of synthetic oligonucleotide probes labeled with biotin (BIO) were designed for the detection of potato spindle tuber viroid (PSTVd), and their sensitivities were compared with that of a digoxigenin (DIG)- or BIO-labeled cDNA probe. Although each oligonucleotide probe alone was less sensitive than the DIG-cDNA probe, sensitivity was increased by using a mixture of two or all of the five oligonucleotide probes. The sensitivity of a PSmix1-5 probe, which was a mixture of five oligonucleotides, was the same as that of a DIG-labeled cDNA probe, which can detect 7.8 pg of purified PSTVd and PSTVd in nucleic acids, equivalent to extracts from 20 microg of infected potato leaf and 310 microg of infected potato tuber. Using the PSmix1-5 probe, PSTVd in all leaves and tubers of seven potato cultivars could be detected without any background. Moreover, with the PSmix1-5 probe, the hybridization time could be shortened to 2 h without any decrease in sensitivity, whereas the sensitivity of the cDNA probes clearly decreased when the hybridization time was shortened. Hybridization using a mixture of several oligonucleotide probes may be applicable to the gene diagnosis of other viroids and viruses.

[A case of chronic inorganic mercury poisoning with progressive intentional tremor and remarkably prolonged latency of P300].

A 59-year-old man showed slowly progressive intentional tremor for 40 years prior to first visit to us in 1996. He was exposed to mercury vapor for about 3 years (1956-1959) and the diagnosis of chronic inorganic mercury poisoning was made. Hasegawa dementia scale-revised (HDS-R), mini-mental state (MMS) examination and P300 examination were performed. HDS-R and MMS were within normal range but the latency of P300 was remarkably prolonged. His tremor was considered to be due to chronic inorganic poisoning because there were no other causes and the frequency of his tremor was 3-4 Hz. which was lower than that in essential tremor. The prolonged P300 latency was also considered to be due to the same cause because there were no other causes and the head MRI were normal. Chronic inorganic mercury poisoning has been reported to produce organic changes in the brain and P300 is considered to be useful to detect these changes.

Selectivity of the parietal visual neurones in 3D orientation of surface of stereoscopic stimuli.

We identified a group of neurones in the posterior parietal cortex of the monkey that responded preferentially to a flat stimulus in a particular orientation on a 3D computer graphics display. We designated these neurones surface-orientation selective (SOS) neurones since they showed tuning to the 3D orientation of the surface. Almost all of the SOS neurones were sensitive to binocular disparity and their responses increased with the width or length of the stimulus, but the responses of only some of them decreased with increasing thickness of the stimulus. These results suggest that SOS neurones extract surface orientation signals from the binocular disparity signals and play an important role in the perception of 3D shape and the visual guidance of hand movement.

Serial imaging of bilateral striatal necrosis associated with acidaemia in adults.

Bilateral striatal necrosis in acute encephalopathy has been reported in a small number of adults with methanol or cyanide intoxication, hypoxic encephalopathy or haemolytic-uraemic syndrome. Acute encephalopathy with bilateral striatal necrosis has been reported in infants and children. However, the pathogenesis of the necrosis remains unclear. This is the first report of serial imaging from the very early to chronic stage in two acute encephalopathic adults with bilateral striatal necrosis. A clinicoradiological study is presented for clarification of the pathological process and pathogenesis. Striatal lesions were not detected in the very early stages, but only thereafter. Serial studies suggested that the lesions were caused by delayed neuronal death. These patients had severe lactic acidosis, near the limit for survival. There have been few reports of adults with acute encephalopathy and bilateral striatal necrosis in whom arterial pH was described; all these exhibited marked acidosis. The common pathophysiological condition among these encephalopathies with bilateral striatal necrosis could be lactic acidosis elicited by impairment of ATP generation through the Krebs cycle. The striatum might represent one of the target areas of Krebs-cycle blockade.

[A case of variant Gerstmann-Sträussler-Scheinker disease with the mutation of codon P105L].

Here we present a case of variant GSS disease with mutations in codons 1055 and 129 in a prion protein. The patient was a 54-year-old male, who developed weakness in the lower limbs and spastic, wide-based gait at the age of 46 years. Subsequently he developed dementia and spastic quadriplegia at the age of 49. He had marked pseudobulbar palsy at the age of 50 and became bed-ridden in decorticated posture at teh age of 53. CT and MRI examinations revealed marked atrophy of the frontal and temporal lobes, but the occipital lobes and the cerebellum were spared. His sister had been reported by Amano, et al. in 1992 as a case of variant GSS syndrome, who had very similar clinical features, and had numerous prion protein positive plaques in her cerebral cortex at the time of autopsy. His sister was confirmed to have the same mutations in a prion protein as the present case in later genetic studies.

Rice ragged stunt Oryzavirus genome segment 9 encodes a 38 600 Mr structural protein.

The complete nucleotide sequence of rice ragged stunt virus genome segment 9 (S9) was determined. The S9 segment is 1132 nucleotides long and has a long open reading frame starting from the first AUG codon at nucleotide position 14-16 and terminating at a UAG codon located at 1028-1030, which could encode a polypeptide with an Mr of 38 600 (P9). The encoded polypeptide has no sequence homology to polypeptides of any other plant reoviruses published previously. An immunological study demonstrated that P9 was the smallest of the structural proteins. The P9 polypeptide was expressed as a fusion protein with maltose binding protein in Escherichia coli. Antisera to purified virions and to the fusion protein reacted with both the bacterially expressed polypeptide and the smallest polypeptide of the purified virus in immunoblotting analyses.

[Development of Wernicke's encephalopathy during the period of oral food intake after a subtotal colectomy for ulcerative colitis].

A 61-year-old woman was hospitalized because of ulcerative colitis which had caused fever, vomiting and diarrhea since June 16, 1992. Then she developed toxic megacolon, and was transferred to our hospital on the 1st of July and underwent subtotal colectomy the same day. After surgery, she received intravenous hyperalimentation (IVH) which contained 1,000 Kcal/day without vitamin supplementation. From the 8th to the 13th post-operative days, she took 3/4 or more of the liquid diet which contained 1,050 Kcal, protein 35 g, carbohydrate 166 g and vitamin B1 0.59 mg per day. From the 14th to the 23rd post-operative days, she ate 4/5 or more of the oral diet which contained 1,700 Kcal/day, protein 68 g, carbohydrate 236 g and vitamin B1 0.93 mg per day. During the 7th to the 23rd day, the IVH was reduced to 800 Kcal and then 500 Kcal per day. She talked less on the 19th post-operative day, and in a few days, her level of consciousness began to decline progressively. On the 27th post-operative day, neurological examinations revealed the following: semi-coma, almost fixed pupils which were 3 mm in diameter, absent doll's eye movement to all directions, flaccid extremities with abolished deep tendon reflexes. Pertinent abnormalities on laboratory data at that time consisted of hemoglobin 7.8 g/dl and serum total protein 5.4 g/dl. Lumbar puncture revealed normal cerebrospinal fluid under normal opening pressure. Cranial magnetic resonance imaging (MRI) taken on the 27th post-operative day demonstrated, on T2-weighted images, symmetrical high intensity lesions in the periventricular areas of the third and fourth ventricles, and periaqueductal area of the midbrain.(ABSTRACT TRUNCATED AT 250 WORDS)

Genomic heterogeneity of rice dwarf phytoreovirus field isolates and nucleotide sequences of variants of genome segment 12.

Electrophoretic profiles of the dsRNAs of field isolates of rice dwarf virus (RDV) were compared with those of an isolate maintained at Hokkaido University (RDV-H). Unexpectedly, the genomic dsRNAs of most of the field isolates showed distinct electrophoretic mobility profiles. This was the case even among isolates from the same region. Genome segment 12 (S12) from some variants migrated faster than S12 from RDV-H. These RNAs were converted to full-length cDNAs and sequenced. S12 from all the variants had the same length of 1066 nucleotides with nucleotide sequence identities of 96 to 99%. Three open reading frames previously reported were present in all the variants, and the sequence identities were 95 to 99% for P12, 98 to 100% for P12OPa, and nearly 100% for P12OPb. A comparison of the nucleotide and amino acid sequences of the variants with sequences of the RDV-H and Akita isolate showed that there are two genomic types, one represented by RDV-H and the other by the Akita isolate.

A PCR-microplate hybridization method for plant virus detection.

A sensitive nonradioactive method for detection of plant viruses was evaluated. A cDNA fragment from the coat protein coding region of the potato virus Y (PVY) RNA genome amplified by reverse transcription (RT) followed by polymerase chain reaction (PCR), was directly adsorbed onto polystyrene microplate wells after heat denaturation. The adsorbed cDNA was hybridized with a digoxigenin (DIG)-labelled cDNA probe without a prehybridization step. The probe was also prepared by PCR using the same pair of primers to amplify the target sequence from a cDNA clone of part of the viral genome. The hybrid of the adsorbed cDNA and DIG-labelled probe was reacted with alkaline phosphatase-conjugated anti-DIG antibody. The enzyme activity was then detected by hydrolysis of a substrate, and the absorbance values were measured using a microplate reader. Highest absorbance values were obtained when the amplified DNA fragments were diluted 100 or 125-fold in 10 x SSC (1.5 M NaCl, 0.15 M sodium citrate) for adsorption. Highly concentrated DNA gave lower absorbance values. The absorbance values differed depending on the microplates used, and the highest value was obtained using Nunc Immunoplate II-Maxisorp microplates. DNA fragments longer than 300 bp all gave similar absorbance values, which were twice as high as those obtained with shorter fragments. When the amplified DNA was diluted 100-fold, 10 fg of PVY genomic RNA could be detected by this method, which is called PCR-microplate hybridization. This is about 10,000 times more sensitive than enzyme-linked immunosorbent assay (ELISA). By this method, PVY was detected from five field potato samples showing to be free from PVY by ELISA. PCR-microplate hybridization is nucleic acid-based ELISA-like highly sensitive diagnostic method, and may be generally applicable for detection of plant viruses, viroids, and possibly other plant pathogens.

Characterization and strain identification of a potato virus Y isolate non-reactive with monoclonal antibodies specific to the ordinary and necrotic strains.

An isolate of potato virus Y, named PVY-36, reacted with polyclonal antibody against PVY-O (an ordinary strain), but not with any of eight monoclonal antibodies (MAbs) specific to PVY-O or with two MAbs specific to PVY-T (a necrotic strain). From its host range and symptomatology, PVY-36 belongs to the PVYO group. The nucleotide sequence of the coat protein (CP) coding region of the PVY-36 genome was determined and the amino acid sequence was predicted. Based on the CP amino acid sequence, PVY-36 is more closely related to PVY-O than to PVY-T. There were eight amino acid differences between the CPs of PVY-36 and PVY-O in the N-terminal 30 amino acids. It is suggested that amino acids 8-15 and/or 26-30 from the N-terminus may determine a PVY-O-specific epitope (or epitopes).