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Biomedical subjects

M Osawa

Publications and source records attributed to M Osawa.

At least 91 records · Page 5Linked to original sources

[A case of chorea gravidarum with moyamoya disease].

A 16-year-old girl developed acute left choreic movements during her fourth week of pregnancy. She had sometimes had transient ischemic attacks since she was 10 years old. During the eighth week of pregnancy, a brain MRI showed old ischemic lesions deep in the right frontal white matter. Her angiograph revealed a complete obstruction of the terminal portion of the right internal carotid artery with a developed moyamoya net work. After her abortion, all involuntary movements completely subsided. The choreic movements might have been caused not only by ischemia, but also by enhanced dopaminergic sensitivity mediated by elevations in female sex hormones due to pregnancy.

Abortion, Therapeutic↗

[Application of the PCR-APLP method to determine ABO genotypes in forensic samples].

We carried out ABO genotyping of forensic samples by the amplified product length polymorphism (APLP) technique. We present two novel systems. One is termed as eight primers system, in which eight allele-specific primers are added into a single PCR reaction. Another is termed as six primers system. In both APLP systems, all alleles were clearly detected using DNA purified from forensic samples. In PCR amplification with direct addition of specimen, ABO genotyping was also possible to blood stain, seminal stain, blood, saliva and urine. Furthermore, ABO genotyping worked only to chimpanzee. This PCR-APLP method should be convepffnt and valuable for forensic practice.

ABO Blood-Group System↗

Further characterization of CD34-low/negative mouse hematopoietic stem cells.

We have previously reported that in adult mouse bone marrow, CD34low/- c-kit+ Sca-1+ lineage markers negative (Lin-) (CD34-KSL) cells represent hematopoietic stem cells with long-term marrow repopulating ability whereas CD34+ c-kit+ Sca-1+ Lin- (CD34+KSL) cells are progenitors with short-term reconstitution capacity. To further characterize cells in those two populations, relative expression of various genes were examined by reverse transcriptase polymerase chain reaction (RT-PCR). In CD34-KSL cells, none of the genes studied was found to be expressed with the exception of GATA-2, IL-1R alpha, IL-2R gamma, AIC-2B, c-kit, EPO-R, and c-mpl. In contrast, expression of GATA-1 and all cytokine receptor genes examined except IL-2R beta, IL-7R alpha and IL-9R alpha were found in CD34+KSL. The difference between these two populations was also shown in single cell culture analysis of these cells. When cells were clone-sorted and cultured in the presence of SCF, IL-3 and EPO, CD34-KSL cells required much more time to undergo the first cell division than CD34+KSL cells. Dormancy and random fashion of cell division by CD34-KSL cells were also evident by the analysis of the second cell division, which was found to be delayed and unsynchronous compared with CD34+KSL cells. Clonal culture analysis showed that CD34-KSL cells were more potent in proliferation and multilineage differentiation capacities than CD34+KSL cells. In a paired-daughter cell experiment, 75% of CD34-KSL and 50% of CD34+KSL paired-daughter-derived colonies were nonidentical with wide variety of lineage combinations. Taken together, these data support our previous notion that CD34-KSL cells are at higher rank in hematopoietic hierarchy than CD34+KSL cells. In addition, our results using highly enriched stem cell population directly obtained from mouse bone marrow support the proposed stochastic nature of lineage commitment.

Animals↗

JTB: a novel membrane protein gene at 1q21 rearranged in a jumping translocation.

1q21 is frequently involved in different types of translocation in many types of cancers. Jumping translocation (JT) is an unbalanced translocation that comprises amplified chromosomal segments jumping to various telomeres. In this study, we identified a novel gene human JTB (Jumping Translocation Breakpoint) at 1q21, which fused with the telomeric repeats of acceptor telomeres in a case of JT. hJTB (human JTB) encodes a trans-membrane protein that is highly conserved among divergent eukaryotic species. JT results in a hJTB truncation, which potentially produces an hJTB product devoid of the trans-membrane domain. hJTB is located in a gene-rich region at 1q21, called EDC (Epidermal Differentiation Complex). This is the first report identifying the gene involved in unbalanced translocations at 1q21.

Amino Acid Sequence↗

Evidence for calmodulin inter-domain compaction in solution induced by W-7 binding.

Small-angle X-ray scattering and nuclear magnetic resonance were used to investigate the structural change of calcium-bound calmodulin (Ca2+/CaM) in solution upon binding to its antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). The radius of gyration was 17.4+/-0.3 A for Ca2+/CaM-W-7 with a molar ratio of 1:5 and 20.3+/-0.7 A for Ca2+/CaM. Comparison of the radius of gyration and the pair distance distribution function of the Ca2+/CaM-W-7 complex with those of other complexes indicates that binding of two W-7 molecules induces a globular shape for Ca2+/CaM, probably caused by an inter-domain compaction. The results suggest a tendency for Ca2+/CaM to form a globular structure in solution, which is inducible by a small compound like W-7.

Animals↗

Association of plasma triglyceride-rich lipoprotein remnants with coronary atherosclerosis in cases of sudden cardiac death.

Among the risk factors for coronary atherosclerosis, elevated LDL-C level is best known. The action of lipoprotein lipase on triglyceride-rich lipoproteins produces remnant lipoprotein particles enriched in cholesterol and apolipoprotein E (apo E). Apo E serves as the ligand for uptake of remnant lipoproteins via the LDL-receptor or the remnant receptor. In this study, postmortem plasma total cholesterol, triglycerides (TG), VLDL-C, HDL-C, lipoprotein (a) [Lp(a)] and remnant-like lipoprotein particles (RLP)-cholesterol, RLP-TG, apolipoproteins B, C III and E were measured, together with LDL-C to assess their potential contribution to the severity of coronary and aortic atherosclerosis of the 197 cases of sudden death (132 cardiac death and 65 non-cardiac death). In all cases, the severity of coronary atherosclerosis was determined at postmortem pathological examination. RLP-cholesterol (RLP-C) and LDL-C concentrations were significantly higher in cases with advanced coronary atherosclerosis compared with those without coronary atherosclerosis; respective median values were 13.5 vs 8.4 mg/dl (P < 0.001) and 140 vs 115 mg/dl (P < 0.05). RLP-C levels were more strongly correlated with the severity score of coronary atherosclerosis than LDL-C.

Adult↗

A comparative study of high-dose and low-dose ACTH therapy for West syndrome.

PURPOSE: A prospective randomized controlled study was conducted for the purpose of identifying the lowest effective ACTH dose, with the fewest adverse effects, for the treatment of West syndrome (WS). SUBJECTS AND METHODS: Twenty-five subjects with cryptogenic (CWS, n = 9) or symptomatic (SWS, n = 16) WS were enrolled in this study. They were randomly assigned to receive either low-dose (0.005 mg/kg per day = 0.2 IU/kg per day) or high-dose (0.025 mg/kg per day = 1 IU/kg per day) synthetic ACTH therapy. ACTH was administered every morning for 2 weeks and tapered to zero over the subsequent 2 weeks. Both effectiveness and adverse effects were compared between the two treatment regimens in each type of WS. RESULT: After completion of the treatment protocol in the CWS group, spasms and hypsarrhythmia were completely suppressed in 3/4 (75%) given the low-dose and 5/5 (100%) given the high-dose treatment. In the SWS group, the spasms and hypsarrhythmia disappeared in 6/8 (75%) in each dose group. There were no significant differences in initial responses between the low-dose and high-dose treatments for either type of WS (P > 0.05). Long-term seizure and developmental outcomes, assessed in the 17 responders who were followed up for longer than 1 year after the completion of ACTH therapy, were also essentially the same. We did not recognize differences in side effect profiles between the two treatment regimens with the exceptions of sleepiness and brain shrinkage estimated by CT scan, both of which were significantly milder in the low-dose than in the high-dose group (P < 0.05). CONCLUSION: Unexpectedly, this prospective randomized controlled study demonstrated the dose of ACTH required for spasm cessation and disappearance of the hypsarrhythmic EEG pattern to be lower than previously believed. A low-dose regimen should thus be considered for CWS, and for SWS associated with significant cerebral atrophy.

Adrenocorticotropic Hormone↗

A novel target recognition revealed by calmodulin in complex with Ca2+-calmodulin-dependent kinase kinase.

The structure of calcium-bound calmodulin (Ca2+/CaM) complexed with a 26-residue peptide, corresponding to the CaM-binding domain of rat Ca2+/CaM-dependent protein kinase kinase (CaMKK), has been determined by NMR spectroscopy. In this complex, the CaMKK peptide forms a fold comprising an alpha-helix and a hairpin-like loop whose C-terminus folds back on itself. The binding orientation of this CaMKK peptide by the two CaM domains is opposite to that observed in all other CaM-target complexes determined so far. The N- and C-terminal hydrophobic pockets of Ca2+/CaM anchor Trp 444 and Phe 459 of the CaMKK peptide, respectively. This 14-residue separation between two key hydrophobic groups is also unique among previously determined CaM complexes. The present structure represents a new and distinct class of Ca2+/CaM target recognition that may be shared by other Ca2+/CaM-stimulated proteins.

Amino Acid Sequence↗

Internal carotid-posterior communicating artery aneurysm associated with unusually short posterior communicating artery.

We report two cases of a ruptured internal carotid-posterior communicating artery aneurysm in which the ipsilateral posterior communicating artery is short and the P1 and P2 segments of the posterior cerebral artery are long. Unique angiographic and operative findings are described. Vertebral angiography with carotid compression is recommended to diagnose this rare variation. Recognition of this variation is important to avoid an inadvertent occlusion of arteries behind the aneurysm at the time of clipping. Copyright 1999 Harcourt Publishers Ltd.

Journal Article↗

Serial intelligence test scores in pediatric moyamoya disease.

Serial intelligence tests in 38 patients with childhood moyamoya disease were evaluated. A total of 98 tests were administered. The IQ scores were classified into three categories: tests performed between the time of onset of symptoms and 5 years after the onset of symptoms (n = 44), tests performed 5-10 years after the onset of symptoms (n=32), and tests performed more than 10 years after the onset of symptoms (n=22). When more than one test was performed during each period, the mean of the IQ scores was used. The IQ tests were administered two or more times to 10 patients in the onset-5-years category, and 5 of them exhibited lower IQ scores on later tests. The IQ scores were significantly lower in the 5-10 years category and in the more than 10 years category (76.8 +/- 23.1 and 73.9 +/- 31.1, respectively) than in the onset-5-years category (92.9 +/- 22.7). The IQ scores for the 5-10 years category and the more than 10 years category did not differ significantly. The IQ in pediatric moyamoya disease begins to decrease after the onset of symptoms, but the decline eventually stabilizes more than 10 years after the onset of symptoms.

Adolescent↗

Novel mutations and genotype-phenotype relationships in 107 families with Fukuyama-type congenital muscular dystrophy (FCMD).

Fukuyama-type congenital muscular dystrophy (FCMD), one of the most common autosomal recessive disorders in the Japanese population, is characterized by congenital muscular dystrophy in combination with cortical dysgenesis (micropolygyria). Recently, we identified, on chromosome 9q31, the gene responsible for FCMD, which encodes a novel 461 amino acid protein which we have termed fukutin. Most FCMD-bearing chromosomes examined to date (87%) have been derived from a single ancestral founder, whose mutation consisted of a 3 kb retrotransposal insertion in the 3' non-coding region of the fukutin gene. FCMD is the first human disease known to be caused primarily by an ancient retrotransposal integration. We under-took a systematic analysis of the FCMD gene in 107 unrelated patients, and identified four novel non-founder mutations in five of them: one missense, one nonsense, one L1 insertion and a 1 bp insertion. The frequency of severe phenotypes, including Walker-Walberg syndrome-like manifestations such as hydrocephalus and microphthalmia, was significantly higher among probands who were compound heterozygotes carrying a point mutation on one allele and the founder mutation on the other, than it was among probands who were homozygous for the 3 kb retrotransposon. Remarkably, we detected no FCMD patients with non-founder (point) mutations on both alleles of the gene, and suggest that such cases might be embryonic-lethal. This could explain why few FCMD cases are reported in non-Japanese populations. Our results provided strong evidence that loss of function of fukutin is the major cause of FCMD, and appeared to shed some light on the mechanism responsible for the broad clinical spectrum seen in this disease.

Base Sequence↗

Study on the early-onset variant of benign childhood epilepsy with occipital paroxysms otherwise described as early-onset benign occipital seizure susceptibility syndrome.

PURPOSE: We studied the early-onset variant of benign childhood epilepsy with occipital paroxysms (EVBCEOP) proposed by Panayiotopoulos, to confirm whether his five criteria are sufficient to delineate EVBCEOP as a new epileptic syndrome, as well as to predict a good outcome prospectively at the time of the first examination. SUBJECTS: The subjects were 649 children with localization-related epilepsies (LREs) observed in our hospital for >4 years. METHODS: We applied the International Classification of Epilepsies and Epileptic Syndromes to the 649 patients and identified patients who had EVBCEOP from among those with nonspecific idiopathic LRE. The inclusion criteria were to satisfy all five criteria and all but one criterion (i.e., either ictal vomiting or occipital EEG paroxysms). We were blind as to the outcomes and selected patients who satisfied the following three of the five criteria at the time of the first examination, (a) normal development before the onset, (b) epilepsy onset age between 2 and 8 years, and (c) occipital EEG foci. We attempted to determine whether the outcome can be predicted prospectively, and whether the presence or absence of ictal vomiting affects the prognosis. RESULTS: We identified 19 patients who satisfied all five criteria, 22 who exhibited all but occipital EEG foci, and 21 who exhibited all but ictal vomiting. The incidence of status convulsivus was higher in those with ictal vomiting than in those without ictal vomiting (p < 0.05). Interictal EEG performed every 6 months showed shifting and multiplication of EEG foci in 42 and 52% of all subjects, respectively. We identified 57 patients, 42 (74%) of whom were in remission by age 12 years. The number of patients who experienced remission did not differ significantly between those with (76%, n = 25) and without (72%, n = 32) ictal vomiting (p > 0.05). CONCLUSIONS: Nosologically, EVBCEOP appears to constitute the earliest form of idiopathic epileptic syndrome different from classic BCEOP. However, its clinical spectrum, ranging from the absence of ictal vomiting to a combination of extraoccipital and multifocal EEG foci, is broad, such that further prospective study is expected to reveal the exact prerequisite criteria for determining the border of this epileptic syndrome and for clarifying the clinical spectrum within this syndrome.

Adolescent↗

[Vibrio vulnificus infection: clinical and bacteriological analysis of four cases].

Vibrio vulnificus (V. vulnificus) infection has recently been drawing attention as a high mortality disease especially in a patient with the preexisting chronic liver disease. The illness caused by V. vulnificus is divided into three groups such as primary septicemia, wound infection and gastrointestinal illness. Primary septicemia, which is the most common in Japan, is defined as a systemic illness presenting fever or hypotension with recovery of V. vulnificus from blood or tissue without the apparent primary focus of infection. We diagnosed four cases as infectious diseases of V. vulnificus by isolating it from each clinical material in Kurashiki Central Hospital from 1984 through 1997. We investigated clinical manifestations of the four cases including season of the onset, presence of drinking habit, underlying diseases, consumption of raw seafood, symptoms, presence of disseminated intravascular coagulation (DIC) or shock, laboratory data, administered antibiotics and the outcomes of the treatment. And for each strain, we also performed in vitro drug susceptibility tests. The age of the patients ranged from 49 to 61 years old (mean 56), and all of the patients were male. Each of them had a chronic liver disease as an underlying disease. Two of them had a history of raw seafood consumption prior to the onset of the illness. Skin manifestations appeared in two of the four patients. All the patients complicated septic shock and DIC. V. vulnificus was isolated from the venous blood cultures of them. Three of the four were given a diagnosis of primary septicemia and one was made a diagnosis of acute cholecystitis which has never been reported previously. Three of the four patients died and only the rest was alive as a result of antimicrobial therapy. In the sensitivity tests, the four strains were revealed to be very sensitive to the antimicrobials such as minocycline, cephalosporins of the third generation and carbapenems. Once patients with a chronic liver disease are infected with V. vulnificus, their prognosis is poor. Every effort should be made to advise not to have uncooked seafood. Physicians should be informed about the characteristics of the disease caused by this bacteria and treat any suspicious case promptly and appropriately.

Bacteriological Techniques↗

Effects of muscle relaxants on EEG, ABR and EMG in rabbits.

The effects of baclofen and pancuronium bromide on evoked electromyogram (EMG), cortical electroencephalogram (EEG) and auditory brainstem responses (ABR) were studied in pentobarbital anesthetized normal rabbits. Evoked EMG was measured in the gastrocnemius muscle by electrical stimulation of the sciatic nerve. Intravenous injection of baclofen decreased EEG and arterial blood pressure and light reflex, however, it had no significant influence on EMG or ABR at doses of 10 and 20 mg/kg/h. Pancuronium bromide immediately inhibited respiration, decreased EEG and EMG, however, it had no significant influence on arterial blood pressure, ABR, or light reflex, at doses of 0.4 and 1.0 mg/kg/h in anesthetized rabbits. ABR waves were observed until just before cardiac arrest with both of the muscle relaxants. It is suggested that ABR are not influenced by central or peripheral muscle relaxants, or by pentobarbital.

Acoustic Stimulation↗

[Monozygotic twins with suspected hereditary sensory and autonomic neuropathy (HSAN) type V].

We report a pair of 1-year-5-month-old female monozygotic twins with generalized loss of pain sensation, but without impairment of other sensory modalities and the diaphoretic function. Routine electrophysiological investigations revealed no abnormalities. Morphometric analysis of biopsied sural nerve showed that the number of small myelinated fibers was reduced and that of unmyelinated fibers was normal or mildly reduced. On the basis of these findings, we suspected a diagnosis of a rare disorder, HSAN type V, which has not previously been reported in Japan.

Diseases in Twins↗