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Biomedical subjects

C Shimizu

Publications and source records attributed to C Shimizu.

At least 73 records · Page 4Linked to original sources
PubMed1997

Genetic analysis of a Japanese patient with butyrylcholinesterase deficiency.

A patient (64-year-old, male) with familial cholinesterasemia caused by BChE deficiency was studied. DNA sequence analysis of all exons identified a point mutation, an A-->G transition at codon 128, resulting in a Tyr-->Cys substitution. The propositus showed extremely low BChE activity, but his other family members (three individuals) showed from intermediate to normal BChE activity. An immunological method revealed the absence of BChE protein in serum of the propositus. Both PCR primer introduced restriction analysis (PCR-PIRA) and sequence analysis revealed all three family members to be heterozygotes for this mutation.

Asian People↗
PubMed1997

A novel missense mutation in codon 218 of the albumin gene in a distinct phenotype of familial dysalbuminemic hyperthyroxinemia in a Japanese kindred.

Familial dysalbuminemic hyperthyroxinemia (FDH) is the most common cause of inherited euthyroid hyperthyroxinemia in Caucasians. To our knowledge, no such documentation on Asians exists. Six of 8 members of a 3-generation Japanese family were found by us to carry the FDH phenotype. Serum total T4 levels ranged from 1763.2-2741.3 nmol/L (normal range, 65.6-164.7), serum total T3 levels ranged from 2.73-5.62 nmol/L (normal range, 1.47-2.95), and rT3 levels ranged from 1.08-2.52 nmol/L (normal range, 0.22-0.60). In the proband, the majority of [125I]T4 in serum T4-binding proteins was distributed in albumin fractions, and the isolated albumin had an increased affinity for T4. A guanine to cytosine transition in the second nucleotide of codon 218, resulting in replacement of normal arginine with proline, was detected in 1 of 2 alleles in all 5 subjects of the family with FDH. In all FDH-affected Caucasian subjects from 10 unrelated families with a moderate increase in serum T4, the guanine to adenine transition was demonstrated at the same position of the albumin gene as noted in our patients, but histidine, the replacement amino acid, differed from proline noted in our FDH Japanese subjects. It would thus appear that FDH has ethnic variations.

Adult↗
PubMed1997

[4-year clinico-statistical observation of outpatients].

Clinico-statistical observations were made on the outpatients visiting the Department of Initial Diagnosis and Emergency, Faculty of Dentistry Hospital, Tokyo Medical and Dental University in 1986, 1987, 1989 and 1990. The following findings were obtained according to sex, age group, and chief complaints of new outpatients. Approximately 60% of the outpatients were female during the year examined. The number of outpatients tended to increase in March and to decrease during the winter. The largest number of new outpatients visiting the hospital was in the 20-24-year-old group in both males and females. In the female patients, the 50-54-year-old group had a relatively higher peak. The greatest chief complaint was tooth pain. Further, the chief complaint involving oral soft tissues was due to inflammation. The main disease diagnosed due to chief complaints was caries in the 20-29-year-old group, marginal periodontitis in the 50-59, pericoronitis of wisdom tooth in the 20-29, temporomandibular joint problem in the < or = 19 and masticatory disturbance in the 60 < or = -year-old groups.

Adult↗
PubMed1996

Genetic mapping of four mouse bHLH genes related to Drosophila proneural gene atonal.

It has been shown that mammalian neurogenesis is partly controlled by multiple basic helix-loop-helix (bHLH) genes, as in Drosophila. Recently, mouse homologs of Drosophila atonal, a proneural gene encoding a bHLH protein required for chordotonal organ and photoreceptor development, have been characterized to obtain further insights into the molecular nature of mammalian neurogenesis. Here, to assess their potential involvement in genetic neural disorders, we have determined genetic map positions for four mouse atonal-related genes, Atoh1, Atoh2, Atoh3, and Ndrf, which encode MATH-1, MATH-2, MATH-3, and NDRF, respectively. Interspecific backcross analysis indicated that Atoh1 and Atoh2 were located in separate positions of Chr 6 and that Atoh3 and Ndrf were mapped to Chr 10 and Chr 11, respectively. Thus, these structurally related genes are located separately on multiple chromosomes.

Amino Acid Sequence↗
PubMed1996

Retrovirol gene transfer in Xenopus cell lines and embryos.

A new class of retroviral vector pseudotypes have an expanded host species range and can be concentrated to high titers by ultracentrifugation. These pantropic vectors contain the genome of the murine leukemia virus-based vectors and the envelope protein of vesicular stomatitis virus substituted for the amphotropic envelope protein. We tested (a) the ability of pseudotyped (pantropic) and unmodified (amphotropic) vectors to stably infect three different Xenopus laevis cell lines, including one derived from the embryonic retina; and (b) the ability of the concentrated pseudotyped virus to infect embryos and to mediate foreign gene expression in the embryonic CNS. Expression of the neomycin phosphotransferase gene and single copy integration of the provirus into the genome of the cell lines was demonstrated. Surprisingly, the amphotropic and pantropic vectors generated neomycin-resistant clones with similar efficiency. PCR amplification of genomic DNA from single stage 10, 20, and 25 embryos microinjected in the blastocoel or neural tube cavities with concentrated pantropic vector (10(8) cfu/ml) revealed proviral DNA. Microinjection of a concentrated pantropic vector containing the coding sequence for the beta-galactosidase gene into the neural tube lumen of 24-h embryos yielded beta-galactosidase expressing cells in the brain. Thus, retroviral vectors provide an additional approach to existing strategies for gene transfer in Xenopus embryos and cell lines.

Animals↗
PubMed1996

Acute anterior uveitis in a child with HLA-B60 after Salmonella enteritis associated with the transient appearance of auto-antibody.

A Japanese girl with HLA-B60, but not B27, who developed acute anterior uveitis after Salmonella enteritis is described. There was no evidence of arthritis or urethritis during this episode. This is the first report that acute anterior uveitis after Salmonella enteritis was associated with the transient appearance of auto-antibody in the serum at an early period.

Antibodies, Antinuclear↗
PubMed1995

A mammalian helix-loop-helix factor structurally related to the product of Drosophila proneural gene atonal is a positive transcriptional regulator expressed in the developing nervous system.

We report the molecular characterization of a mouse basic helix-loop-helix factor, designated MATH-1, structurally related to the product of the Drosophila proneural gene atonal. MATH-1 mRNA is first detected in the cranial ganglions and the dorsal part of the central nervous system on embryonic day 9.5 (E9.5). From E10.5 onward, prominent expression of MATH-1 continues in the dorsal part of the central nervous system but becomes restricted to the external granular layer of the cerebellum by E18 and is undetectable in the adult nervous system. MATH-1 activates E box-dependent transcription in collaboration with E47, but the activity is completely antagonized by the negative regulator of neurogenesis HES-1. These results suggest that MATH-1 may be a target of HES-1 and play a role in the differentiation of subsets of neural cells by activating E box-dependent transcription.

Amino Acid Sequence↗
PubMed1995

MATH-2, a mammalian helix-loop-helix factor structurally related to the product of Drosophila proneural gene atonal, is specifically expressed in the nervous system.

In Drosophila, multiple helix-loop-helix (HLH) factors play an essential role in neural development. Mammalian homologues of such Drosophila HLH factors have been recently characterized and provide useful information for the analysis of the mechanisms of mammalian neurogenesis. We report here the molecular characterization of a novel mouse HLH factor, designated MATH-2, that has a structural homology to the product of Drosophila proneural gene atonal. MATH-2 consists of 337 amino acid residues and contains an atonal-related basic HLH domain. However, outside of this domain, there is no significant sequence similarity between MATH-2 and Atonal. MATH-2 expression occurs by embryonic day 11.5 (E11.5), and is first detected in the wall of brain vesicles as well as in the spinal cord. It is expressed in the cortical plate and the mantle layer throughout the developing central nervous system but not in the ventricular zone. By E13.5, the expression becomes more prominent in the cortical plate of the cerebrum but decreases in the other regions. In the adult, the cerebrum produces a high level of MATH-2 RNA but other neural tissues produce only low levels. MATH-2 RNA is not detected in non-neural tissues, indicating that MATH-2 expression is specific to the nervous system. The gel mobility-shift analysis shows that MATH-2 can interact with several E-box sequences in collaboration with E47, a ubiquitously expressed HLH factor. These results raise the possibility that MATH-2 may be a trans-acting factor involved in the development and maintenance of the mammalian nervous system.

Amino Acid Sequence↗
PubMed1995

Serial magnetic resonance imaging in post-infectious focal encephalitis due to influenza virus.

Two cases of a 13-year-old girl and a 14-year-old boy with postinfectious focal encephalitis due to influenza are reported. The clinical and magnetic resonance imaging (MRI) findings included: (1) partial motor seizures as the initial central nervous system manifestation, appearing more than 20 days after the influenzal infection, (2) no change in the level of consciousness although a boy demonstrated apraxia, and (3) high signal intensity lesions noticed with T2-weighted MRI located mainly in the cortex. The girl's lesion appeared to resolve within 10 days on MRI, while that of the boy (demonstrated in the thalamus on a third MRI) resolved within 1 week. However, a new lesion appeared in the cortex approximately 1 month later, that was visualized on a fourth MRI. Small gadolinium-enhanced lesions also were noticed during earlier stages in both patients. The pathogenesis of these MRI lesions is unknown, but the coexistence of small enhancing lesions, rapidly resolving lesions, and the elevated thrombin anti-thrombin III complexes, may indicate the presence of an angiopathy. Serial MRI examinations in patients with postinfectious encephalitis may lead to a better understanding of the pathogenesis of this disorder.

Adolescent↗
PubMed1995

Molecular identification of viruses in sudden infant death associated with myocarditis and pericarditis.

A subset of infants dying suddenly and unexpectedly have myocarditis with or without pericarditis found at autopsy. To address whether viruses known to cause infantile myocarditis and pericarditis might be present in such infants, we examined myocardium, liver and skeletal muscle for the presence of genomic sequences from adenovirus, cytomegalovirus, enterovirus and echovirus 22/23 in infants enrolled in a comprehensive evaluation protocol. We studied eight infants who died suddenly and unexpectedly with histologic evidence of myocarditis and/or pericarditis detected at postmortem examination. One infant with myocarditis and pericarditis had adenovirus genome detected in the myocardium. In an additional infant with severe pericarditis alone, enterovirus genome was detected in the liver. Although echovirus 22/23 has been associated with myopericarditis in young infants, no previous studies have used molecular methods to search for the genomic sequences of these viruses in clinical samples. No echovirus 22/23 genome was detected in the patients reported here. The significance of enterovirus and adenovirus genome in the tissues of two patients dying suddenly and unexpectedly remains speculative but raises the possibility that pathogenic viruses may cause little or no clinical symptoms and yet be contributory to sudden death in young infants.

Adenoviridae↗
PubMed1995

[The efficacy of intravenous lidocaine on various types of neuropathic pain].

We examined the efficacy of systemic local anesthetics on various types of neuropathic pain in 89 patients. Lidocaine 1.5 mg.kg-1 was infused intravenously for one minute. Pain score (PS) by visual analogue scale (VAS, 0-10) was measured 1, 5, 15 and 35 min after the infusion. The efficacy of intravenous lidocaine was evaluated by PS which was lowest after infusion. PS decreased to less than 50 percent of pre-infusion value in more than 75 percent of cases of cancer pain, postherpetic neuralgia, trigeminal neuralgia, low back pain with signs of root pain or spinal canal stenosis, peripheral nerve injury and thalamic pain, in 50-75 percent of cases of herpetic neuralgia, and in less than 50 percent of cases of cervical spondylosis, spinal cord injury, reflex sympathetic dystrophy, causalgia and psychogenic pain. This study suggests that systemic local anesthetics is effective in neuropathy due to cancer pain, postherpetic neuralgia, trigeminal neuralgia, low back pain with signs of root pain or spinal canal stenosis, peripheral nerve injury and thalamic pain.

Aged↗
PubMed1995

[Diltiazem potentiates the neuromuscular blockade by vecuronium in humans].

We investigated interaction of diltiazem with vecuronium using constant infusion technique in 24 ASA class I or II elective surgical patients with no preoperative administration of Ca antagonists. Neuromuscular blockade was evaluated with accelerometry, which measured single twitch height of adductor pollicis muscle. After tracheal intubation under isoflurane anesthesia, patients received either no diltiazem (control group, n = 8)m, 5 mg (bolus) + 2 mcg.kg-1.min-1 constant infusion (2 mcg group, n = 8) or 5 mg (bolus) + 4 mcg.kg-1.min-1 constant infusion (4 mcg group, n = 8). When single twitch height returned to 10% of control value, infusion of vecuronium was started and the infusion rate was adjusted to maintain twitch height at 10% of the control value. After 30 minutes of stable twitch height, the vecuronium infusion rate and plasma diltiazem concentrations were measured. Diltiazem infusion of 4 mcg.kg-1.min-1 decreased the vecuronium infusion rate by 45% compared with 2 other groups. Plasma diltiazem concentrations in patients receiving 4 mcg.kg-1.min-1 were significantly higher than those receiving 2 mcg.kg-1.min-1. In conclusion diltiazem 4 mcg.kg-1.min-1 potentiates the neuromuscular blockade of vecuronium and it relates with the plasma diltiazem concentration.

Adult↗
PubMed1995

Regulation of mammalian neural development by helix-loop-helix transcription factors.

Understanding of the molecular mechanisms of mammalian neural development has been greatly advanced by identification and characterization of the molecules homologous to the factors regulating Drosophila neurogenesis, which provides a powerful model system. Studies of Drosophila show that transcription factors with a helix-loop-helix (HLH) domain play an essential role in neurogenesis. Several lines of evidence demonstrate that mammalian homologues of the Drosophila HLH factors do also play an essential role in neural development. Mash-1, a mammalian HLH factor homologous to the products of Drosophila proneural genes achaete-scute complex, is a positive regulator of neurogenesis and required for differentiation of olfactory and autonomic neurons. In addition, HES-1, another mammalian HLH factor homologous to the products of Drosophila hairy and Enhancer of split, antagonizes the activity of Mash-1 and negatively regulates neurogenesis. Thus, positive and negative HLH factors interact with each other, and the balance between them is important for the developmental processes. Recent studies show that many other HLH factors exist expressed in the developing mammalian nervous system. In this article, the authors review mammalian HLH factors expressed in the nervous system and discuss the molecular aspect of mammalian neurogenesis.

Amino Acid Sequence↗
PubMed1994

One-step determination of herpes simplex virus types I and II by polymerase chain reaction.

A rapid and sensitive one-step polymerase chain reaction (PCR) assay was developed for use in identifying type I and type II herpes simplex virus (HSV). Although the nucleotide sequences of the two HSV subtypes are quite similar, common and type-specific sequences 20 nucleotides in length could be deduced in the thymidine kinase gene. Oligonucleotide primers targeted to the type-specific regions generated products of different sizes that served to distinguish two HSV types. Type-specific PCR amplification products were verified by restriction enzyme digestion. Specificity of the HSV PCR was established by the lack of amplification of other herpes-group viruses including cytomegalovirus, Epstein-Barr virus, and varicella zoster virus. Extraction of DNA from clinical materials (throat swabs, vesicular swabs, cerebrospinal fluid and eye discharge) yielded an amplification product of the predicted size for each HSV type. Thus, this PCR system provides a rapid, sensitive and specific assay that can supplement the currently available modalities for detecting and typing HSV.

Base Sequence↗
PubMed1994

Detection of novel RNA viruses: morbilliviruses as a model system.

Recent advances in molecular detection of viral-specific nucleic acid sequences have facilitated the search for pathogenic viruses in clinical samples. Primers for the polymerase chain reaction can be targeted to unique or conserved regions of the viral genome. While the design of primers must be based on known sequences, it has been demonstrated in bacteria that amplification with primers which hybridize to highly-conserved regions of the genome can be exploited to detect new agents. By taking advantage of sequence conservation among diverse members of a viral genus, we designed PCR primers capable of hybridizing to three different members of the genus Morbillivirus for which sequence information is available. Simultaneous amplification with primers for the porphobilinogen deaminase gene, a constitutively expressed gene in all cells, confirmed the presence of amplifiable RNA. Sequence alignments for the matrix and nucleoprotein genes suggested a highly conserved region of the nucleoprotein gene as a likely target for gene amplification. Morbillivirus primer pairs were chosen from the nucleoprotein gene, which successfully amplified measles virus, canine distemper virus, and phocine distemper virus. In a single reaction which combines cDNA synthesis by reverse transcription of the RNA genome with the polymerase chain reaction (RT PCR reaction), amplification with these primers detected as little as 0.1 pfu (plaque forming unit) of measles virus and 1 TCID50 of canine distemper virus. These Morbillivirus primers can be used to search for novel members of the genus which are likely to share sequence similarity in these highly conserved regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1994

Acute leucoencephalopathy during cyclosporin A therapy in a patient with nephrotic syndrome.

A 13-year-old girl with nephrotic syndrome (NS) developed acute leucoencephalopathy during combination therapy with cyclosporin A (CyA) and prednisolone (PSL). The patient had a generalized motor seizure followed by coma at 19 days after CyA administration. Magnetic resonance scanning performed on the 1st hospital day revealed white matter lesions in the subcortices of the parietal and occipital lobes, brain stem and cerebellum. These lesions had completely resolved on the 10th hospital day. This episode might be caused by CyA because the clinical course and laboratory data revealed neither inflammation nor other causative factors. To our knowledge, this is the first report of acute leucoencephalopathy during combination therapy with CyA and PSL in a patient with NS.

Acute Disease↗
PubMed1994

Substituted 1,8-naphthyridin-2(1H)-ones as selective phosphodiesterase IV inhibitors.

New substituted 1,8-naphthyridin-2(1H)-ones have been found to exhibit highly selective phosphodiesterase (PDE) IV inhibition. These compounds inhibited polymorphonuclear leukocyte activation induced by N-formylmethionyl-leucyl-phenylalanine and caused relaxation of isolated guinea pig trachea precontracted by histamine or leukotriene D4. In anesthetized guinea pigs, presensitized with the antigen, these compounds also alleviated airway constriction induced by the antigen. Since these compounds differ in their chemical structure compared with theophylline and other PDE IV inhibitors so far reported and some of them have been shown to be well tolerated in acute toxicity studies, they will provide a new tool for investigating the possible relationship between PDE IV inhibition and anti-asthmatic activity.

3',5'-Cyclic-AMP Phosphodiesterases↗