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A Ogawa

Publications and source records attributed to A Ogawa.

At least 37 records · Page 2Linked to original sources
PubMed2001

Reverse aromatic cope rearrangement of 2-allyl-3-alkylideneindolines driven by olefination of 2-allylindolin-3-ones: synthesis of alpha-allyl-3-indole acetate derivatives.

The reverse aromatic Cope rearrangement of 2-allyl-3-alkylideneindolines obtained by Horner-Wadsworth-Emmons olefination of 2-allylindolin-3-ones was performed. When 2-allylindolin-3-ones were treated with phosphonium ylides in refluxing toluene, domino Wittig reaction and reverse aromatic Cope rearrangement took place to give alpha-allyl-3-indole acetate derivatives in good yields. The aromatization as a new driving force in the Cope rearrangement is preferable to the conjugation with the carbonyl and cyano groups and also to the alkyl substitution pattern, which are well-known driving forces.

Journal Article↗
PubMed2001

Chirality organization of ferrocenes bearing podand dipeptide chains: synthesis and structural characterization.

A variety of ferrocenes bearing podand dipeptide chains have been synthesized to form an ordered structure in both solid and solution states and have been investigated by 1H NMR, FT-IR, CD, and X-ray crystallographic analyses. Conformational enantiomerization through chirality organization was achieved by the intramolecular hydrogen bondings between the podand dipeptide chains. The single-crystal X-ray structure determination of the ferrocene 2 bearing the podand dipeptide chains (-D-Ala-D-Pro-OEt) revealed two C2-symmetric intramolecular hydrogen bondings between CO (Ala) and NH (another Ala) of each podand dipeptide chain to induce the chirality-organized structure. The molecular structures of the ferrocene 1 composed of the podand L-dipeptide chains (-L-Ala-L-Pro-OEt) and 2 are in a good mirror image relationship, indicating that they are conformational enantiomers. An opposite helically ordered molecular arrangement was formed in the crystal packing of 2 as compared with 1. The ferrocene 2 exhibited induced circular dichroism (CD), which appeared at the absorbance of the ferrocene moiety. The mirror image of the CD signals between 1 and 2 was observed, suggesting that the chirality-organized structure via intramolecular hydrogen bondings is present even in solution. The ferrocene 4 bearing the podand dipeptide chains (-Gly-L-Leu-OEt) also showed an ordered structure in the crystal based on two intramolecular hydrogen bondings between CO (Gly) and NH (another Gly) of each podand dipeptide chain, together with intermolecular hydrogen bondings between CO adjacent to the ferrocene unit and NH (neighboring Leu) to create the highly organized self-assembly. A different self-assembly was observed in the crystal of the ferrocene 5 composed of the podand dipeptide chains (-Gly-L-Phe-OEt), wherein each molecule is bonded to two neighboring molecules through two pairs of symmetrical intermolecular hydrogen bonds to form a 14-membered intermolecularly hydrogen-bonded ring. These ordered structures based on the intramolecular hydrogen bondings in the solution state are also confirmed by 1H NMR and FT-IR.

Circular Dichroism↗
PubMed2001

Activation in the ipsilateral posterior parietal cortex during tool use: a PET study.

The basis of perceptual assimilation of tool and hand has been considered to be in modification of body schemata, for which integration of multimodal sensory information about our body parts is required. Using positron emission tomography and H(2)(15)O, we aimed to identify brain regions that change their neural activity in association with changes in neural processing of visual and/or somatosensory information when humans use a simple tool. Normal subjects were instructed to manipulate a small graspable object with a pair of tongs or with the fingers of their right or left hand. The only site activated during manipulation with the tool, compared with the fingers, with the right hand was the lateral edge of the right intraparietal sulcus (IPS). During manipulation using the left hand with the tool, compared with using the fingers, an area in the middle part of the left IPS was activated. Areas in the contralateral hemisphere were activated during both the tool-use and the finger-use tasks compared to the control task, but there was no statistically significant difference between the tool-use and the finger-use tasks. Therefore, the results suggest that the ipsilateral posterior parietal cortex was recruited during the tool-use tasks to integrate visuosomatosensory information.

Adult↗
PubMed2001

Clinicopathological study of unilateral multiple breast cancer.

BACKGROUND: The tendency for breast cancer to form multiple lesions is important to consider when planning breast-conserving surgery. However, many unknowns remain regarding the pathology and prognosis of multiple breast cancer, and therefore it is clinically significant to investigate its clinicopathological properties. METHODS: Over the past 25 years, in the period between April 1972 and March 1997, we investigated the clinicopathological findings including the 5-year and 10-year survival rates of 66 patients treated for unilateral multiple breast cancer. RESULTS: Of the total of 1,334 female patients with unilateral breast cancer who underwent curative surgery at our hospital, we identified 66 (5.0%) patients with unilateral multiple cancer. The incidence of such cancer has been higher in recent years. Of the 66 patients, 50 (75.8%) were premenopausal, and the remaining patients were postmenopausal, but multiple cancer among postmenopausal women is a recent phenomenon. The ER positivity rate of the main lesion in patients with multiple breast cancer was 69.2% and that of PgR was 50.0%. The 5-and 10-year overall survival rate in all 66 patients with multiple breast cancer was 90.8% and 79.7%, respectively. CONCLUSION: In the past, multiple breast cancer was frequently identified in premenopausal women. However, the current findings indicate that its incidence among postmenopausal women has increased in recent years. In addition, prognoses were comparable for patients with multiple or solitary breast cancer, a relevant finding in the planning of breast-conserving surgery.

Adult↗
PubMed2001

Brain PET and technetium-99m-ECD SPECT imaging in Lhermitte-Duclos disease.

Two patients with Lhermitte-Duclos disease were evaluated by brain positron emission tomography (PET) and technetium-99m-ethyl cysteinate dimer (99mTc-ECD) single-photon emission computed tomography (SPECT). In the lesions in both patients, hyperperfusion was detected on cerebral blood flow images obtained by PET, and hyperactivity by standard 99mTc-ECD SPECT. Dynamic 99mTc-ECD SPECT images demonstrated a plateau of activity in each lesion. These findings suggest that lesions in Lhermitte-Duclos disease have a retention mechanism for 99mTc-ECD equivalent to that of normal neural tissue.

Adolescent↗
PubMed2001

Combination of early and delayed SPET imaging using technetium-99m ethyl cysteinate dimer immediately after local intra-arterial thrombolysis.

The aim of this study was to investigate the prognostic utility of post-treatment technetium-99m ethyl cysteinate dimer (99mTc-ECD) single-photon emission tomography (SPET) for predicting ischemic tissue outcome in cases involving embolic middle cerebral artery occlusion treated with local intra-arterial thrombolysis. We examined twenty-five patients with a moderately ischemic area determined using pretreatment technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) SPET, and with complete recanalization within 6 h. Post-treatment 99mTc-ECD SPET studies, consisting of scanning for 0.5-6.5 min (early scan) and 15-21 min (delayed scan) after tracer injection, were performed immediately after thrombolysis. The extent of the affected area outlined on pretreatment 99mTc-HMPAO SPET was used for the post-treatment early and delayed 99mTc-ECD SPET images, and the AR/CE ratio (ratio of affected regional activity to cerebellar activity) was calculated. The washout index of 99mTc-ECD in the affected area was also calculated by dividing the difference between the AR/CE ratio in the early and delayed images by the AR/CE ratio in the early image. Twelve patients without infarction or with small subcortical/basal ganglial infarction, ten with medium or large cortical infarction, and three with hemorrhage were identified by follow-up computed tomography. Although the AR/CE ratio in post-treatment early 99mTc-ECD SPET images was significantly higher in the hemorrhagic group than in the cortical infarction group, this value did not differentiate the reversible ischemia group from either the cortical infarction or the hemorrhagic group. The AR/CE ratio in post-treatment delayed 99mTc-ECD SPET images statistically differentiated the reversible ischemia group from both the cortical infarction and the hemorrhagic group. However, the difference between the cortical infarction and hemorrhagic groups was not statistically significant. The washout index of 99mTc-ECD statistically differentiated all three groups. This study demonstrated that a combination of early and delayed 99mTc-ECD SPET imaging performed immediately after thrombolysis predicts ischemic tissue outcome.

Adult↗
PubMed2001

Double cancers in the common bile duct: molecular genetic findings with an analysis of LOH.

We report a 69-year-old man with double cancers in the common bile duct. One cancer was located between the superior and middle parts of the bile duct, while the other cancer was in the inferior part of the bile duct. Pylorus-preserving pancreatoduodenectomy was performed. There was no communication between the two cancers in either the mucosal layer or the subepithelial layer. On pathological examination, the upper cancer was diagnosed as poorly differentiated adenocarcinoma, while the lower one was found to be moderately differentiated adenocarcinoma. We analyzed loss of heterozygosity (LOH), using microsatellite markers on five chromosomal arms, in both the upper and the lower cancers. Both cancers showed common regions of LOH at 5q, 6q, 9p, 17p, and 18q, whereas the upper cancer showed one additional region of LOH at 8p, thus suggesting progression, due to the acquisition of the additional LOH, in the upper cancer. No LOH was observed in the region between the two cancers. The presence of one additional LOH in the upper cancer suggests that the upper cancer was a metastasis of the lower one.

Adenocarcinoma↗
PubMed2001

Intrathecal administration of nicardipine hydrochloride to prevent vasospasm in patients with subarachnoid hemorrhage.

OBJECT: To evaluate the prophylactic effect of repeated intrathecal administration of nicardipine associated with hypertensive hypervolemic hemodilution therapy (triple H) and sodium correction, we analyzed a consecutive series of 177 patients with subarachnoid hemorrhage. METHODS: All patients received aneurysmal clipping and placement of cisternal drainage within 48 hours of the onset. Intrathecal administration of 4 mg of nicardipine was performed every 12 h. Nicardipine concentrations in the cerebrospinal fluid (CSF) and blood before and after its administration were analyzed. Angiographic vasospasm (aVS), symptomatic VS (sVS), and clinical outcome 6 months after onset were also evaluated. RESULTS: Nicardipine concentration in CSF on day 9 was 231.44 +/- 51.51 ng/ml (mean +/- SD), and that of blood was 21.05 +/- 15.57 ng/ml. Twenty patients (11.3%) showed aVS, and ten of those (5.7%) showed sVS (six were transient and four were permanent). Those with good outcome (assessed as good recovery and moderately disabled) 6 months after onset were 89.2% of the total. The number of patients requiring a shunt operation was 33 of 177 (18.6%), and 11 patients presented intracranial infection. CONCLUSIONS: These results suggest that our strategy may well prevent VS. However, hydrocephalus and infection may be serious disadvantages that should be resolved.

Adolescent↗
PubMed2001

Expression and prognostic significance of O6-methylguanine-DNA methyltransferase in hepatocellular, gastric, and breast cancers.

BACKGROUND: O6-Methylguanine-DNA methyltransferase (MGMT) is an enzyme that repairs O6-methylguanine, a promutagenic DNA base damaged by endogenous and environmental alkylating agents. There are few reports that describe whether or not abnormal MGMT expression correlates with the prognosis in human solid cancers. METHODS: The expression of MGMT was immunohistochemically evaluated in 60, 62, 105, and 46 paraffin-embedded samples from patients with curatively resected hepatocellular, gastric, colorectal, and breast cancers, respectively. RESULTS: The expression of MGMT was a positive predictive factor for overall survival in hepatocellular (P = .005) and gastric cancers (P < .001) and for relapse-free survival in breast cancers (P < .001). MGMT-positive gastric tumors (n = 42) were correlated with the absence of serosal invasion (P = .045), lymph node metastasis (P = .006), intestinal type (P = .018), and low pathological tumor, node, metastasis stage (P < .001). All breast tumors that recurred locally after operation were MGMT negative (P = .004). The clinicopathologic characteristics of colorectal cancers with respect to MGMT expression did not significantly differ. CONCLUSIONS: The expression of MGMT is a predictive prognostic marker in patients with hepatocellular, gastric, and breast cancers. These findings may help to establish therapeutic strategies for patients with these types of solid cancer.

Aged↗
PubMed2001

Cerebral blood flow imaging in arteriovenous malformation complicated by normal perfusion pressure breakthrough.

BACKGROUND: A patient with normal perfusion pressure breakthrough (NPPB) after surgical removal of an arteriovenous malformation (AVM) was evaluated using single photon emission computed tomography cerebral blood flow (CBF) imaging. CASE DESCRIPTION: A 48-year-old man suffered consciousness disturbance because of an intraventricular hemorrhage and underwent ventricular drainage. Cerebral angiography showed a medium-sized AVM in the left parietal lobe. Three months after the ictus, a left parietal craniotomy was performed and total removal of the AVM was achieved. A brain region adjacent to the AVM with preoperative decreased vasoreactivity to acetazolamide showed marked hyperperfusion after AVM excision. Hemorrhage subsequently occurred in this area. CONCLUSION: CBF mapping seems to offer a noninvasive method for the preoperative identification of AVM patients at risk for NPPB, and to allow for early postoperative diagnosis of NPPB.

Blood Flow Velocity↗
PubMed2001

Clinical and pedigree study on familial cases of West syndrome in Japan.

Nationwide survey on familial cases of West syndrome (WS) in first- and second-degree relatives was conducted by mailing a questionnaire to 64 major university hospitals, children's hospitals, and epilepsy centers in Japan, and by review of the Japanese cases in the literatures. Thirty-four familial cases, 20 males and 14 females, were obtained in 15 families including one with five affected members in two generations and another with three affected male siblings including a half brother by a different father (X-linked WS). A mother and the child or children were involved in three families. Nine families had 21 cryptogenic cases and six families had 13 symptomatic cases, and the etiologies were same among the affected members in each family. Familial cases of WS have characteristic clinical features and genetic mechanisms. Age of onset, seizure types, electroencephalographic abnormalities, early seizure outcome, effective treatment, long-term seizure prognosis, and long-term developmental prognosis were concordant among the affected members in each family. Long-term seizure and developmental prognoses were far better than those in WS in general, with seizure-free rate of 82% and normal mental development rate of 44%. Poor prognosis was limited to specific symptomatic cases. Adrenocorticotropic hormone (ACTH) was a treatment of choice, and even in relapse of WS after ACTH therapy, the patients well responded to antiepileptic drugs. Specific inheritance pattern was difficult to imagine in the majority of the present cases, except for one family with X-linked WS and another family with five patients of maternal inheritance. These results are helpful for the treatment choice and prognostication of clinical course for familial cases of WS.

Adrenocorticotropic Hormone↗
PubMed2001

The role of different X-inactivation pattern on the variable clinical phenotype with Rett syndrome.

A gene for Methyl-CpG binding protein 2 (MECP2), which locates Xq28, was recently found to be responsible for Rett syndrome. Although mutational analyses of MECP2 in Rett syndrome have been extensively analyzed, the mechanism(s) by which variable clinical phenotype occurred between affected monozygotic twins or sisters have not been clarified. We hypothesized that the difference of X-inactivation pattern might explain this phenomenon. With the method based on methylation-specific PCR, we analyzed polymorphic trinucleotide repeat in the human andorogen receptor gene mapped on Xq11.2-12, using DNA samples derived from previously described monozygotic twins and sisters together with their parents. Their clinical phenotypes were reported to be significantly different between siblings. We found that (1) maternally derived allele is predominantly active than paternally derived one in three out of four patients analyzed, (2) remaining one twin patient, whose ratio of active paternal allele is almost the same level as maternal allele, showed far much severe phenotype when compared with her counterpart. Together with the finding that most of the alleles with de novo mutation are from paternal X chromosome in sporadic cases, the existence of a mechanism that suppresses mutated paternal allele activation, resulting skewed X-inactivation to make clinical phenotype milder, might be speculated. Thus, when this mechanism fails to work sufficiently by an unknown reason, severer clinical phenotype could occur.

Adult↗
PubMed2001

Polymorphisms in the coding region of mtDNA and effects on clinical outcome of unrelated bone marrow transplantation.

The entire protein-coding region was divided into 45 fragments, separately amplified and analyzed for polymorphism by the PCR-SSCP (single-strand conformation polymorphism) method. The effect of polymorphism mismatching on the clinical outcome of unrelated bone marrow transplantation was studied to clarify whether products from mtDNA become minor antigens. Variability in PCR-SSCP pattern combinations of the 45 fragments suggests that each individual has a different polymorphism combination in the protein-coding region if all the coding regions were compared at the nucleotide sequence level. Nonsynonymous polymorphisms were found at relatively high frequency in MTATP8 and MTND3. Both the polymorphisms with and without substitution matched the peptide-binding motifs of HLA-A*0201. The effects of the polymorphism matching were retrospectively analyzed in 340 recipients transplanted with HLA-A, -B, -DRB1 allele-matched bone marrow from unrelated donors. There were no effects of polymorphism matching on the incidence of acute GVHD and cumulative disease-free survival. These results suggest that polymorphisms which generate peptides, with and without substitutions, that bind the same HLA molecule hardly influence GVHD because the difference between the HLA-peptide complexes is minute.

Bone Marrow Transplantation↗
PubMed2001

E variants found in Japanese and c antigenicity alteration without substitution in the second extracellular loop.

BACKGROUND: The molecular basis of E variants in the Japanese population is poorly understood. In this study, molecular analysis of E variants detected in Japanese by serologic methods was carried out. STUDY DESIGN AND METHODS: E variants from healthy Japanese blood donors were screened by serologic analysis using E MoAbs. Fifteen E variant samples were divided into three types--EFM, EKH, and EKK-on the basis of patterns of reactivity with five distinct E antibodies. The entire coding region of the Rh cDNAs from the E variant samples was analyzed by sequencing. RESULTS: Although the Rh cDNA sequences of the three types were different from each other, those of the EFM-type variants (RHEFM) had a partial DNA exchange in exon 5 between the RHCE and RHD genes, generating an RHcE variant (Gln233Glu, Met238Val). The cDNA of EKH-type variants (RHEKH) exhibited a point mutation (G461C) in exon 3 of the RHcE allele that resulted in an Arg154Thr substitution in the third external loop of the RhcE peptide. The EKK-type variant (RHEKK) carried a hybrid gene structure characterized by replacement of exons 1-3 (or 2-3) of the RHCE gene with those of the RHD gene. The RHD gene of a person possessing an E variant of the EKK type was also a hybrid gene, D-cE(2-3)-D or cE(1-3)-D (RHDKK). The E variants of types EKH and EKK showed weak c antigenicity. CONCLUSION: In serologic screening of 140,723 Japanese blood donors, 15 were found to possess E variants (0.011%). A new RHCE variant, RHEKH, was identified. On the basis of the variants found in this study, the c antigenicity seemed to be determined not only by Pro-103 but also by the structure of the third extracellular loop or the amino acids contained in it.

Amino Acid Substitution↗
PubMed2001

Treating chronic diffuse sclerosing osteomyelitis of the mandible with saucerization and autogenous bone grafting.

OBJECTIVE: Chronic diffuse sclerosing osteomyelitis of the mandible is a difficult-to-treat disease characterized by recurrent symptoms. The purpose of this study was to determine the results of particulate cancellous bone and marrow grafting after saucerization in the surgical treatment of diffuse sclerosing osteomyelitis of the mandible. STUDY DESIGN: Six patients with chronic diffuse sclerosing osteomyelitis of the mandible were treated by particulate cancellous bone and marrow grafting after saucerization and were retrospectively evaluated. Treatment results were evaluated with repeated comprehensive clinical investigation and radiologic/scintigraphic analysis. RESULTS: After the surgical procedure, all patients indicated maintenance of mandible continuity, contour, and function. Furthermore, 3 patients were symptom-free and the remaining 3 patients exhibited improvement. CONCLUSIONS: The partial resection of the mandible is associated with disadvantages, including loss of mandibular support, dysfunction, and problems related to mandibular reconstruction. Therefore, it would be reasonable to choose saucerization combined with particulate cancellous bone and marrow grafting, which is a relatively conservative surgical treatment for chronic diffuse sclerosing osteomyelitis of the mandible.

Adolescent↗
PubMed2001

Alzheimer beta amyloid deposition enhanced by apoE epsilon4 gene precedes neurofibrillary pathology in the frontal association cortex of nondemented senior subjects.

To clarify how Alzheimer disease pathology develops in the brains of nondemented subjects, we examined the interrelations among the amounts and morphology of Abeta deposition, neurofibrillary pathology, and apolipoprotein E (ApoE) genotype in the frontal association cortex of 101 autopsy brains from patients aged between 40 to 83. Senile plaque density correlated well with the logarithmic data of insoluble Abeta measured by enzyme immunoassay (EIA). The amounts of Abeta42-ETA increased dramatically in the late preclinical stage, whereas the AP42+ plaque density increased in the early preclinical stage. Neurofibrillary pathology appeared only in the areas with severe Abeta deposition and in subjects aged over 70. The ApoE epsilon4 allele enhanced the Abeta3 deposition in presenile subjects. Plaque-associated glial Abeta was prominent in subjects with mild to moderate Abeta deposition. The morphology of cerebral Abeta deposition changed from diffuse plaques with small amounts of Abeta in each plaque in the early preclinical stage to primitive/neuritic plaques with larger amounts of Abeta in each plaque in the late preclinical stage. Our findings suggest that the prevention of Abeta deposition in the late preclinical stage can be a rational therapeutic target, especially in elderly people with ApoE epsilon4 allele.

Adult↗