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Biomedical subjects

K Ohara

Publications and source records attributed to K Ohara.

At least 37 records · Page 2Linked to original sources

[Chemoradiotherapy and salvage surgery in a patient with advanced esophageal cancer].

We report a case of advanced esophageal cancer, which was treated by chemoradiotherapy combined with surgical treatment. Moreover, 14 advanced esophageal cancer patients treated by chemoradiotherapy are discussed. The chemoradiotherapy showed beneficial control of the tumor; however, it sometimes leads to esophageal stenosis and ulcer. We conclude that additional salvage surgery is needed for such complications.

Antineoplastic Combined Chemotherapy Protocols↗

Presenilin-1 in late-onset depressive disorder.

Late-onset depressive disorder (LOD) is thought to be associated with dementia. Allele 1 in the presenilin-1 (PS-1) gene is a risk factor for Alzheimer's disease. An association study on this polymorphism was performed in depressive patients and control subjects. The patients were subdivided into those with early onset and late onset, using 50 years as the cut-off age. There was no statistically significant difference in the age of onset of depressive disorders according to the PS-1 genotype. There was also no association between early/late-onset depressive disorders and the PS-1 genotype. Our results suggest there is no association between the PS-1 allele and LOD.

Aged↗

A CAG trinucleotide repeat expansion and familial schizophrenia.

Studies which showed anticipation in families with schizophrenia suggested that a trinucleotide repeat expansion mechanism may be involved in the pathogenesis of familial schizophrenia. Furthermore, some studies involving the repeat expansion detection (RED) method showed the median length of CAG repeats to be longer in probands with schizophrenia than that in control subjects. We screened for a possible expanded CAG repeat by means of the direct identification of repeat expansion and cloning technique in 23 subjects (affected, 14; unaffected, 9) from six families with schizophrenia which showed anticipation. The polymorphism of a long and unstable CAG/CTG trinucleotide repeat, Dir1, was studied by PCR. No unusual expanded CAG/CTG trinucleotide repeat was detected in the subjects with familial schizophrenia. There was no significant difference between the affected and unaffected subjects in the allele frequency of Dir1. Our results suggest that a CAG expansion is not the mechanism underlying familial schizophrenia.

Adult↗

Polymorphism in the promoter region of the alpha(2A)-adrenergic receptor gene and panic disorders.

alpha(2)-Adrenergic receptors have been thought to play a crucial role in the etiology or treatment of panic disorders. Polymorphism(s) in the promoter region of the alpha(2) receptor may affect gene expression and be associated with panic disorders. We studied the polymorphism of the alpha(2A) receptor gene at position -1291 reported by Lario et al. (Lario, S., Calls, J., Cases, A., Oriola, J., Torras, A., Rivera, F., 1997. Short repeat on DNA marker at candidate locus. MspI identifies a biallelic polymorphism in the promoter region of the alpha(2A)-adrenergic receptor gene. Clinical Genetics 51, 129-130.) in 114 healthy control subjects and 55 patients with panic disorders. There was no statistically significant difference between controls and patients in either genotype or allele frequency. Our results suggest there is no association between this polymorphism in the promoter region of the alpha(2A) receptor gene and panic disorders.

Adult↗

Benefits of adjuvant radiotherapy after radical resection of locally advanced main hepatic duct carcinoma.

PURPOSE: The objective of this study was to determine the benefits of adjuvant radiotherapy after radical resection of locally advanced main hepatic duct carcinoma (Klatskin tumor). METHODS AND MATERIALS: We conducted a retrospective review of 63 patients who underwent surgical resection of Stage IVA Klatskin tumor. Of the 63 patients, 47 had microscopic tumor residue (RT1). Twenty-eight of the 47 patients with RT1 were treated by adjuvant radiotherapy and the remaining 19 patients were treated exclusively by surgical resection. Seventeen of the 28 patients with RT1 were treated by both intraoperative radiotherapy (IORT) and postoperative radiotherapy (PORT); of the remaining 11 patients with RT1, 6 underwent resection and IORT, and 5 underwent resection and PORT. RESULTS: The major complication and 30-day operative death rates were significantly lower in the radiation group (9.5% and 0.0%, respectively) than in the resection alone group (28.5% and 9.5%, respectively). Of the eight 5-year survivors with RT1, 6 had adjuvant radiotherapy and the remaining 2 had resection alone. Adjuvant radiotherapy for patients with RT1 yielded significantly (p = 0.0141) higher 5-year survival rates (33.9%) than in the resection alone group (13.5 %). The best 5-year survival rate (39.2 %) was found in patients who underwent a combination of IORT and PORT after resection. The local-regional control rate was significantly higher in the adjuvant radiation group than in the resection alone group (79.2% vs. 31.2%). CONCLUSION: Our data clearly suggest the improved prognosis of patients with locally advanced Klatskin tumor by integrated adjuvant radiotherapy with IORT and PORT to complete gross tumor resection with acceptable treatment mortality and morbidity.

Adult↗

Ulnar artery graft for myocardial revascularization.

We present a 60-year-old man who underwent coronary artery bypass grafting using an ulnar artery as one of the grafts intended to release angina pectoris. Previously, his right leg had been amputated following a traffic accident. The blood supply of his left leg was reduced due to atherosclerotic stenotic change (left ankle pressure index 0.6). He had been under treatment for severe diabetes mellitus for 4 years. Coronary angiography revealed severe stenosis in the triple coronary artery system. Immediate myocardial revascularization was considered necessary. We considered that saphenous vein grafts and bilateral internal thoracic artery grafts were unsuitable for this patient. Moreover, Allen's test was positive in the bilateral forearms. Coronary artery bypass surgery consisted of left internal thoracic artery grafting to the left anterior descending artery, right gastroepiploic artery grafting to the right coronary artery, and left ulnar artery grafting to the diagonal branch. No myocardial or hand complications were observed after surgery. Following a review of the Japanese literature, we conclude that our case is the first report of an ulnar artery graft for coronary artery bypass grafting in Japan.

Angina Pectoris↗

Bovine herpesvirus 1 glycoprotein G is required for viral growth by cell-to-cell infection.

The bovine herpesvirus 1 (BHV-1) US4 gene encodes glycoprotein G (gG), which is conserved in the majority of alphaherpesviruses. In order to identify the role of BHV-1 gG in the viral infection cycle, a gG minus BHV-1 mutant and its gG-positive revertant were constructed and their growth characteristics in Madin-Darby bovine kidney (MDBK) cells were compared. The gG minus mutant formed smaller plaques than the gG-positive BHV-1 in MDBK cells. When a monolayer culture of MDBK cells was infected with BHV-1 at a low multiplicity of infection and overlaid with semi-solid growth medium, under which adsorption of the mature virion released in the medium was inhibited, gG-positive BHV-1 multiplied, while the growth of the gG negative BHV-1 was severely inhibited. These data suggest that BHV-1 gG functions in direct cell-to-cell transmission mechanism of BHV-1 in tissue culture.

Animals↗

Proton magnetic resonance spectroscopy of lenticular nuclei in simple schizophrenia.

1. The lenticula nuclei have been suggested to be the site of structural and functional abnormalities in schizophrenia. 2. Recently, several studies involving proton magnetic resonance spectroscopy (1H MRS) showed that the ratio of N-acetyl-aspartate (NAA) to choline-containing compounds (Cho) was significantly reduced in the basal ganglia region in patients with schizophrenia. 3. Simple schizophrenia is characterized by social withdrawal and affective flattening, but not by prominent catatonic, hebephrenic or paranoid features. 4. We studied, using 1H MRS, the lenticula nuclei of 10 patients with simple schizophrenia, and 10 age- and sex-matched healthy controls. 5. No differences between the patients and the controls were found in any of the measured ratios, i.e. Cho/Cr, NAA/Cr and NAA/Cho. 6. Our results suggest the normal viability of neuronal cells, as found on quantification of NAA, Cr and Cho, in the lenticular nuclei of patients with simple schizophrenia. 7. The pathophysiology of simple schizophrenia may be different from those of other types of schizophrenia.

Adult↗

Removal of catalytic activity by EDTA from antibody light chain.

Gp41 peptide antigen of the HIV-1 envelope (TP41-1:TPRGPDRPEGIEEEGGERDR, a highly conserved region) was enzymatically degraded by the antibody light chain 41S-2-L after an induction period. The peptide bond between Glu14 and Gly15 was cleaved early in the reaction. When EDTA was added in the induction period, it inhibited the degradation of TP41-1 thus ceasing the catalytic activity of 41S-2-L. In contrast, when EDTA was added after the induction period, only a small reduction in the catalytic activity was observed. These observations suggest that metal ions are important in stimulating catalytic activity early in the reaction.

Amino Acid Sequence↗

Genetic changes in sweat gland carcinomas.

The molecular pathogenesis of malignant appendageal tumors is poorly understood. Immunohistochemical staining, polymerase chain reaction (PCR)-based loss of heterozygosity (LOH) and sequencing analyses were performed in a mixed group of 21 sweat gland carcinomas. LOH was mostly confined to the chromosome arm 17p. None of the remaining 17 tumors showed LOH at any loci. Nuclear accumulation of p53 protein was observed in 3 tumors, all of which also showed LOH of 17p. One eccrine gland adenocarcinoma showed allelic loss of 17p and a Cys 176 Arg mutation in the p53 gene. The other three tumors that showed LOH of 17p, however, had wild-type p53 genes. A clear transition from benign eccrine poroma to porocarcinoma that was associated with p53 protein stabilization and allelic loss was observed in one tumor. One eccrine porocarcinoma/undifferentiated adnexal carcinoma showed prominent microsatellite instability, probably reflecting an underlying defect in DNA mismatch repair. Overexpression of erbB-2 was observed in three tumors. The low frequencies of LOH and p53 alterations in sweat gland carcinomas contrasted with the multiple genetic defects normally observed in cutaneous squamous cell carcinomas, and may be partly explained by the relative protection of cutaneous appendages from ultraviolet light and other environmental mutagens.

Adenocarcinoma↗

Acquired digital arteriovenous malformation: a report of six cases.

Arteriovenous malformation (AVM) is usually congenital, but an acquired type is also known, of which most are due to a previous injury. We report six patients with acquired digital AVM, all having a small patch of AVM localized to the tip of one finger, and therefore quite different from ordinary AVM which consists of a large pulsatile mass. Histologically, dilated venous and arterial vessels were present in the dermis. Tumour-like growth was absent; thus, these six cases could be differentiated from arteriovenous haemangioma. Because of the characteristic anatomical site, unique clinical manifestations and histology, this appears to be a new and distinctive entity.

Adolescent↗

A bladder preservation regimen using intra-arterial chemotherapy and radiotherapy for invasive bladder cancer: a prospective study.

BACKGROUND: A prospective study was performed to investigate combined treatment with intra-arterial chemotherapy and radiation therapy for bladder preservation in locally invasive bladder cancer. METHODS: Patients with invasive bladder cancer, stage T2-3N0M0, were included in the study. Intra-arterial chemotherapy was performed with three injections of methotrexate and cisplatin at 3-week intervals. Simultaneously, the patients underwent X-ray irradiation (40 Gy) of the small pelvic space. Where a post-treatment transurethral resection (TUR) biopsy showed no residual tumor, the tumor site was irradiated by a 30 Gy proton beam and the bladder was preserved. Where tumors remained, radical cystectomy was performed. RESULTS: Between 1990 and 1996, 42 patients were treated according to this protocol. Post-treatment TUR biopsy and urine cytology showed no residual tumors in 39 of 42 cases (93%). The bladder was preserved in accordance with the study protocol in 36 cases. A median follow-up of 38 months showed 3-year non-recurrence in 72% of bladder-preserved patients and the rate of bladder preservation was 84%. The nine recurrences included eight cases of superficial bladder recurrence. One cancer death occurred among the bladder-preservation patients, giving 3-year survival and cause-specific survival rates of 84% and 100%, respectively. Although bladder function decreased slightly in compliance, bladder capacity was retained in almost all cases. CONCLUSIONS: This regimen is useful for bladder preservation in T2-3 locally invasive bladder cancer. Information from more cases and the results of more long-term observations are needed, as is an evaluation of appropriate subject selection and factors associated with quality of life issues, particularly regarding bladder function.

Aged↗

Deteriorating ischemic stroke in 4 clinical categories classified by the Oxfordshire Community Stroke Project.

BACKGROUND AND PURPOSE: The aim of this study was to investigate the frequency, possible predictive factors, and prognosis of deteriorating ischemic stroke in 4 clinical categories according to the classification of the Oxfordshire Community Stroke Project (OCSP). METHODS: A total of 350 patients with first-ever ischemic stroke who presented within 24 hours of onset were enrolled. Based on the OCSP criteria, cerebral infarctions were divided into the following 4 clinical categories: total anterior circulation infarcts (TACI), partial anterior circulation infarcts (PACI), lacunar infarcts (LACI), and posterior circulation infarcts (POCI). Clinical deterioration was defined as a decrease of >/=1 points in the Canadian Neurological Scale (CNS) (in TACI, PACI, and LACI) or Rankin Scale (RS) (in POCI) during 7 days from the onset. In each clinical category, deteriorating (D) and nondeteriorating (ND) patients were compared in terms of their background characteristics, risk factors, vital signs, laboratory data, and cranial CT at the time of hospitalization. The acute-phase mortality and functional outcome were also compared. RESULTS: The subjects comprised 86 patients (24.6%) with TACI, 63 (18.0%) with PACI, 141 (40.3%) with LACI, and 60 (17.1%) with POCI. Overall, 90 patients (25.7%) deteriorated. The frequency was very high in TACI (41.9%), followed by LACI (26.2%) and POCI (21.7%), whereas it was very low in PACI (6. 3%). There were some clinical variables that differed significantly between D and ND groups. In the patients with TACI, early abnormalities of the cranial CT and significant stenoses in corresponding arteries were more frequent in the D than the ND group. In those with LACI, the CNS and hematocrit were lower in the D than the ND group. In those with POCI, cerebral atrophy was more severe and significant stenoses in vertebrobasilar arteries were more frequent in the D than ND group. The mortality of the D groups of patients with TACI and POCI exceeded 35%, and the functional outcome was worse in the D group than in the ND group of patients with TACI, LACI, and POCI. CONCLUSIONS: The frequency of deterioration in acute ischemic stroke significantly differed among the OCSP subgroups, and deterioration worsened the prognosis. There were some factors that could predict deterioration: early CT findings in TACI, large-artery atherosclerosis in TACI and POCI, and stroke severity in LACI. Further research to find sophisticated radiological and chemical markers appears to be needed.

Acute Disease↗

Attachment and penetration of canine herpesvirus 1 in non-permissive cells.

Canine herpesvirus 1 (CHV-1) has a relatively narrow host cell range when compared to other alphaherpesviruses. The early events of CHV-1 infection in a permissive Madin-Darby canine kidney (MDCK) and non-permissive cell lines. In order to quantify attachment and penetration, were investigated quantitative competitive PCR (QCPCR) method was established for quantitation of CHV-1 DNA. In all non-permissive cells tested, no significant decrease in viral attachment was observed. When CHV-1 was treated with heparin, viral attachment to MDCK cells was reduced by 25% of the input CHV-1 attached to MDCK cells even in the presence of 50 microg/ml heparin. However, the attachment of CHV-1 to non-permissive cells was severely impaired by heparin treatment. In permissive MDCK cells, about 80% of attached CHV-1 penetrated into cells. However, only 4-10% of CHV-1 attached to non-permissive cells penetrated into cells. Our data indicated that CHV-1, like other herpesviruses, attached to permissive MDCK cells through two mechanisms: the first one is through the interaction mediated by heparan sulfate (HS) on the cell surface and the second involves unidentified viral component and the cellular receptor. In contrast, the non-permissive cells lacked the cellular receptor for the second attachment mechanism and the defect in viral penetration into non-permissive cell might be related to the lack of the cellular receptor.

Animals↗

[Pitfalls in the assessment of radioresponse as determined by tumor regression: consideration based on the location and histologic constitution of tumors].

PURPOSE: To prove the following hypotheses regarding tumor shrinkage after radiotherapy. Tumors located on an outer tissue surface, e.g. esophageal tumors, shrink faster than parenchymal tumors, e.g. lymph-node metastasis, because two clearance mechanisms, exfoliation and absorption, can operate in the former type of tumors whereas only absorption can function in the latter. Tumors which are being controlled do not necessarily respond completely, because tumors are constituted not only of tumor cells but also stromal tissues that are difficult to be absorbed. MATERIALS AND METHODS: Long-term shrinkage patterns of a parenchymal tumor were determined by using 18 curatively irradiated hepatomas. Preoperatively irradiated thymomas (10) and lymph-node metastases (37) from head and neck cancers were examined histopathologically. Twenty-one esophageal cancers were used for intra-patient response comparison between the primary disease and the lymph-node metastases. RESULTS: Shrinkage patterns were generally biphasic: rapid exponential regression followed by a plateau phase. Histologically, thymomas generally consisted of predominant fibrous tissues and few remaining tumor cells. Radioresponse did not predict the presence of remaining cancer cells in the lymph nodes. Esophageal-cancer radioresponse was always higher for the primary disease than the lymph-node metastases. CONCLUSION: The location and histologic constitution of tumors must be taken into account in predicting radiocurability using radioresponse.

Carcinoma, Hepatocellular↗