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Biomedical subjects

K Ohara

Publications and source records attributed to K Ohara.

At least 55 records · Page 3Linked to original sources
PubMed2000

Matrix metalloproteinase activity is enhanced during corneal wound repair in high glucose condition.

PURPOSE: (1) To investigate the effect of elevated extracellular glucose on migration, proliferation, and the activity of matrix metalloproteinases (MMPs) of SV40-transformed human corneal epithelial cells (HCEC). (2) To examine MMP activity in wounded corneal epithelium in diabetic rats. METHODS: HCEC were cultured in media containing 5.5 mM or 31.2 mM D-glucose, or in a combination of 5.5 mM D-glucose and 25.7 mM D-mannitol on fibronectin/collagen I-coated 48-well plates. After reaching confluence (day 0), cells in the central part of the plate were wounded and the residual cells were cultured for 3 days. Migration and proliferation were evaluated by assessing the increasing amount of area covered by cells, and the day-3 to day-0 ratio of DNA levels, respectively. To determine MMP activity, cells were reacted with synthetic fluorogenic substrates specific to MMPs 1, 2, 3, 7, 9, and MMP activity was determined by a fluorometric kinetic assay. Diabetic rats were induced by streptozotocin injection. Corneal epithelium was scraped from limbus-to-limbus and allowed to heal. Normal rats were treated similarly to serve as controls. Healing epithelium was collected 24 hours later, and gelatin zymography was performed. RESULTS: In the cell culture study, migration in 31.2 mM glucose was significantly slower than that in 5.5 mM, but proliferation in each concentration was similar. The osmotic effect of D-mannitol did not alter migration or proliferation. MMP activity in 31.2 mM was significantly higher than that in 5.5 mM. Zymography revealed enhanced activity of pro and active MMP-9 in healing corneal epithelium in diabetic rats. CONCLUSIONS: MMP activity was enhanced in healing corneal epithelium, both in in vitro and in vivo diabetic models, suggesting its involvement in diabetic keratopathy.

Animals↗
PubMed2000

Current surgical strategy for post-infarction left ventricular aneurysm--from linear aneurysmecomy to Dor's operation.

The surgical strategy for left ventricular (LV) aneurysm after myocardial infarction has been changing recently. Conventionally, linear aneurysmectomy has been widely performed as a standard procedure for post-infarction LV aneurysm. However, this technique remains unsatisfactory because LV distortion occurs postoperatively and an akinetic or dyskinetic area persists in the ventricular septum, resulting in limited improvement of cardiac function. To overcome these problems, Dor and associates excluded all akinetic or dyskinetic myocardium from the left ventricle including the septum and placed a tight circumferential suture around the aneurysmal base to reduce the LV volume and return the LV contour to near normal (endoventricular circular patch plasty: EVCPP). As an alternative to conventional linear aneurysmectomy, EVCPP (Dor's operation) is now being performed more widely for the treatment of post-infarction LV aneurysm, and it achieves better postoperative cardiac function. Recently, EVCPP has attracted interest as a treatment for post-infarction large akinetic scars and ischemic cardiomyopathy (ICM), both of which have a poor prognosis. In this article, based on the author's clinical experience and on the literature, EVCPP is reviewed with respect to its indications for patients with post-infarction LV aneurysm or large akinetic scars, and pointers and results for this technique are discussed.

Cardiac Surgical Procedures↗
PubMed2000

Free-floating left atrial ball thrombus early after mitral valve replacement.

A 61-year-old woman was found to have a free-floating ball, thrombus in the left atrium on echocardiographic examination 2 weeks after mitral valve replacement and tricuspid, annuloplasty. The free-floating thrombus was successfully, removed by an open-heart procedure without clinical sequelae. The diagnostic value of routine echocardiography on follow-up of valve surgery is emphasized.

Female↗
PubMed2000

[Triplet repeat disease from the aspect of psychiatric disease].

Since 1991, about 20 triplet repeat expansion disorders have been reported. They are clinically characterized by anticipation, worsening severity or earlier age at the onset with each succeeding generation, and imprinting, a process whereby specific genes are differentially, marked during parental gametogenesis, resulting in their differential expression. The anticipation in psychoses was pointed out in the 19th century, but it was ignored because no one knew the mechanism at that time. The discovery of triplet repeat expansion diseases has reawakened interest in anticipation in psychiatric diseases. Anticipation has been confirmed in schizophrenia, mood disorders, and anxiety disorders. Molecular approaches have been taken to reveal the involvement of a triplet repeat expansion mechanism in psychoses. Most efforts have been made for CAG-type trinucleotide repeats. So far, most results did not support a trinucleotide repeat expansion mechanism also in psychoses. One plausable explanation for the "false positive" result is the presence of CAG trinucleotide repeats, which are highly polymorphic but not associated with an obvious abnormal phenotype. The screening for triplet repeats besides those of the CAG type remain to be performed.

Humans↗
PubMed1999

Age of onset anticipation in anxiety disorders.

Anticipation, an increase in severity or a decrease in the age of onset inherent in the transmission of a disease gene from an affected parent to a child, is being increasingly described in human diseases. In this study we searched for possible anticipation in anxiety disorders. Seventeen unilineal families who had anxiety disorders were compared across two successive generations as to age at the onset of anxiety disorders. Life table analyses revealed a significant decrease in the onset of anxiety disorders from older to younger generations. No evidence of a difference in the type of anxiety disorder was found. Anticipation was thus found in families with anxiety disorders and, if it is confirmed by other studies, trinucleotide repeat sequences may be considered to account for the familial aggregation of anxiety disorders.

Adult↗
PubMed1999

Proton magnetic resonance spectroscopy of lenticular nuclei in obsessive-compulsive disorder.

Magnetic resonance spectroscopy (MRS) is a safe and non-invasive technique for the in vivo study of brain chemistry and metabolism. As such, it is highly applicable to the study of living brain tissue in psychiatric diseases. Several neuropathological and neuroimaging studies have suggested that abnormalities of the basal ganglia nuclei might be implicated in patients with obsessive-compulsive disorder (OCD). In the present study, we performed proton [1H]MRS of the lenticular nuclei in 12 patients with OCD and 12 healthy normal comparison subjects. The peaks of N-acetyl-aspartate (NAA), creatine (Cr), and choline-containing compounds (Cho) were measured. No differences between OCD patients and normal subjects were found in the NAA/Cr, Cho/Cr and NAA/Cho ratios. Our results suggest the normal viability of neuronal cells, as indicated by the quantification of NAA, Cr and Cho in the lenticular nuclei of patients with OCD.

Adult↗
PubMed1999

Lack of association between alpha1-antichymotrypsin polymorphism and late-onset depressive disorder.

Late-onset depressive disorder (LOD) has been thought to be associated with dementia. Recently, it was reported that the position-15 (alanine) polymorphism of the alpha1-antichymotrypsin gene (ACT*A) was a risk factor for Alzheimer's disease. We wondered whether the ACT*A allele frequency might be elevated in LOD. ACT genotyping was performed as described by Kamboh et al. (Kamboh, M.I., Sanghera D.K., Ferrell R.E., DeKosky, S.T., 1995. APO* E4-associated Alzheimer's disease risk is modified by alpha1-antichymotrypsin polymorphism. Nature Genetics 10, 486-488) in 153 patients with depressive disorders and 107 healthy controls. 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 ACT genotype. There was also no significant association between early-/late-onset depressive disorders and the ACT genotype. In addition, there was no association between the apolipoprotein E epsilon 4 allele and the ACT genotype in LOD. Our results suggest that there is no association between the ACT*A allele and LOD.

Adolescent↗
PubMed1999

Schizophrenia and the serotonin-2A receptor promoter polymorphism.

Serotonin-2A (5-HT2A) receptors have received much investigative attention in schizophrenia because (1) several studies have shown a decrease in the number of 5-HT2A receptors in the prefrontal cortex of postmortem brains of schizophrenic patients; (2) atypical antipsychotic drugs are antagonists for 5-HT2A receptors; and (3) a positive association between a T to C polymorphism at position 102 of the 5-HT2A receptor gene and schizophrenia has been reported. A G to A polymorphism at position -1438 of the 5-HT2A receptor gene was studied in 119 schizophrenic patients and 106 healthy control subjects, all of whom were Japanese. The genotype and allele frequencies did not differ between the patients and control subjects. Furthermore, the genotype frequency did not differ according to diagnostic subtype, family history, age at onset of illness, or daily dosage of antipsychotic medication. Our results suggest that the polymorphism does not contribute to the etiology or clinical characteristics of schizophrenia. However, the gene is greater than 20 kbp in length, and thus it is possible that other areas that affect expression of the gene may vary. We found that the -1438G/A variant was in linkage disequilibrium with the T102C polymorphism.

Adult↗
PubMed1999

Apolipoprotein E epsilon 4 allele and Japanese late-onset depressive disorders.

BACKGROUND: Several studies have suggested that late-onset depressive disorder (LOD) and the apolipoprotein E (Apo E) epsilon 4 allele are associated with dementia, respectively. The Apo E polymorphism is significantly heterogeneous among races. We hypothesized that the Apo E epsilon 4 allele frequency is elevated in Japanese LOD. METHODS: The Apo E genotype was studied in 134 patients (male, 53; female, 81) with early-/late-onset depressive disorder and 105 healthy normal controls (male, 41; female, 64). The patients were subdivided into those with early onset and late onset using 45 and 50 years as the cutoff ages. All the subjects were Japanese. RESULTS: There was statistically no difference between normal control subjects and patients with depressive disorders in Apo E genotype or allele frequency. There was statistically no difference in the age of onset of depressive disorders according to the Apo E genotype. There was no relation between the age of onset of depressive disorder and the number of epsilon 4 alleles the patient had. There was also no association between early-/late-onset depressive disorder and the Apo E genotype or allele frequency. CONCLUSIONS: Our results suggest that there is no association between the Apo E epsilon 4 allele and Japanese LOD.

Adult↗
PubMed1999

Angioma serpiginosum: a report of 2 cases identified using epiluminescence microscopy.

BACKGROUND: Angioma serpiginosum is a rare, acquired vascular lesion simulating purpura, and should be differentiated from purpuric dermatoses such as Henoch-Schonlein purpura. OBSERVATIONS: We report 2 cases of angioma serpiginosum examined using epiluminescence microscopy. Characteristic findings of angiomas ("red lagoons") were observed entirely or focally in these 2 cases, but not in 4 cases of Henoch-Schonlein purpura and a case of senile purpura. CONCLUSION: Epiluminescence microscopy is beneficial in distinguishing angioma serpiginosum from purpuric dermatoses.

Adolescent↗
PubMed1999

Ultrasound biomicroscopy of ciliary body cysts.

PURPOSE: To report the incidence and sector distribution of ciliary body cysts in normal subjects and to assess association with age using ultrasound biomicroscopy. METHODS: We prospectively examined 232 eyes of 116 normal subjects (51 men and 65 women) ranging in age from 15 to 84 years (mean +/- SD, 45.2 +/- 20.1). Complete ophthalmic examination, including gonioscopy and ophthalmoscopy with mydriasis, was performed. In addition, the circumference of the ciliary body was divided into eight sectors, and scanned in transverse and radial sections by high-resolution ultrasound biomicroscope to determine the incidence, distribution, and location of cysts. RESULTS: Based on one randomly chosen eye from each subject, cysts were detected in 63 (54.3%) of the 116 subjects. Cysts were found most frequently and in greater numbers in the inferior and temporal sectors. The incidence and the distribution range, expressed as the number of involved sectors per eye, were 73.1% and 3.8, respectively, for subjects 20 approximately 29 years old; both incidence and the number of involved sectors decreased with age (P = .0001). Cyst diameter ranged from 200 to 2500 microm; mean size decreased with age (P = .001). Gender and refractive error did not affect the incidence and distribution. There was significant bilateral correlation in the number, incidence, and distribution of ciliary body cysts. CONCLUSION: Ultrasound biomicroscopy disclosed a high incidence of ciliary body cysts in normal subjects, which decreased with age. Cysts were multiple and bilateral in many subjects.

Adolescent↗
PubMed1999

A variable-number-tandem-repeat of the serotonin transporter gene and anxiety disorders.

1. A polymorphism of the variable-number-tandem-repeat (VNTR) in the second intron of the serotonin transporter (ST) gene, which has been reported to be associated with major depression, was studied in anxiety disorders. 2. The VNTR of the human ST gene was compared between 103 patients with anxiety and 106 controls. 3. The frequency of the allele containing 12 copies of the VNTR element (STin2.12) was significantly higher in the combined patient group (p = 0.027), and among patients with OCD (p = 0.0326), and GAD (p = 0.0123), in comparison with in controls. 4. The presence of the STin2.12 allele was significantly associated with the risk of combined anxiety disorders (odds ratio = 2.06, 95% CI 1.09-3.90), OCD (10.2, 1.34-77.4), and GAD (3.61, 1.23-10.6).

Adolescent↗
PubMed1999

Loricrin gene mutation in a Japanese patient of Vohwinkel's syndrome.

Vohwinkel's syndrome (VS) is a rare, dominantly inherited keratoderma with pseudoainhum. Recently, a mutation in loricrin gene has been reported in two VS families of British extraction. In the present study, we examined the loricrin gene mutation in a Japanese VS patient. The patient was a 20-year-old woman. She had palmoplantar keratoderma, constricting bands encircling all the fingers, fifth toes, wrist, and neck. She also had generalized mild ichthyosis and suffered from acoustic impairment. Her parents and a brother showed no skin abnormality. Histopathology of the patient revealed hyperkeratosis with parakeratosis, together with hypergranulosis. The clinical and histopathological findings were consistent with an ichthyotic (or Camisa) variant of VS. The sequence analysis of the loricrin gene revealed that the patient had a heterozygous mutation identical to that described in previous reports, i.e. a G insertion producing a frameshift at codon 231 with an abnormal C-terminus. These results clearly demonstrate that a common loricrin gene mutation underlies VS in different ethnic groups.

Adult↗
PubMed1999

Angiolymphoid hyperplasia with eosinophilia associated with arteriovenous malformation: a clinicopathological correlation with angiography and serial estimation of serum levels of renin, eosinophil cationic protein and interleukin 5.

We present a case of angiolymphoid hyperplasia with eosinophilia (ALHE) affecting the auricular area of a 31-year-old man, which clinically mimicked arteriovenous malformation (AVM). The histology and laboratory data distinctively revealed ALHE, while angiography demonstrated typical findings of AVM. Although several reports have hitherto mentioned the relationship between ALHE and AVM, the aetiology of the disease remains unknown. During the 3 years treatment course, we performed angiography several times to assess the efficacy of the treatments and compared the clinical and pathological findings, based on the hypothesis that AVM might be a cause of ALHE. This study showed first, that the clinicopathological findings of ALHE correlated with the extent of AVM shown by angiography, so that AVM could be a primary cause of ALHE. Secondly, systemic corticosteroids and local irradiation therapy produced only a temporary effect on the inflammatory changes of ALHE; therefore, surgical resection is recommended as a curative treatment. Thirdly, the patient's serum levels of renin, eosinophil cationic protein and interleukin 5 corresponded closely with the clinical course of ALHE.

Adult↗
PubMed1999

Metastatic lymph-node clearance from head and neck epidermoid carcinomas following radiotherapy.

Although tumor clearance is a common criterion in assessing the impact of radiotherapy (RT), it is not always reliable. Patterns of tumor clearance were determined using 91 metastatic lymph nodes (LNs) from 51 patients with head and neck tumors treated by definitive RT (61-80 Gy) or preoperative RT (43-65 Gy). Clearance rate (CR) was estimated as a daily volume decrement expressed as a ratio to the pre-RT LN volume. CR was greater for the so-called radioresponsive nasopharyngeal subgroups and more poorly differentiated than those of oral cavity and well-differentiated, respectively. Histologically, LNs that were removed following RT consisted mainly of fibrous tissues, necrotic tissues, and few cancer cells. There was no difference in CR between the cancer-cell-positive group (n = 21) and the cancer-cell-negative group (n = 31). Although the CR may reflect inherent radiosensitivity of tumor cells, tumor persistence predicts the amount of oncologically inactive materials rather than that of remaining cancer cells.

Carcinoma, Squamous Cell↗
PubMed1999

Prognostic significance of the PC10 index for patients with stage II and III oesophageal cancer treated with radiotherapy.

The monoclonal antibody PC10 is used for immunohistochemical staining of the proliferating cell nuclear antigen (PCNA). The percentage of PC10-positive cancer cells is defined as the PC10 index. We evaluated the relationship between the PC10 index in pretreatment endoscopic biopsies and the prognoses of 47 patients with Stage II-III oesophageal squamous cell carcinoma treated with radiotherapy. The patients with a PC10 index > 40% had significantly poorer prognoses than the other patients (p = 0.0007). Proportional hazards model analysis indicated that only the PC10 index was a prognostic factor (p = 0.0009). The patient group of complete responders showed significantly lower PC10 indices compared to patients with a partial response or no change (p = 0.049). The PC10 index can be a good predictive indicator of the prognosis in patients with Stage II-III oesophageal cancer treated with radiotherapy.

Aged↗
PubMed1999

Correlation between symptomatic, radiological and etiological diagnosis in acute ischemic stroke.

OBJECTIVES: The aim of this study was to correlate with the symptomatic, radiological and etiological diagnosis in acute ischemic stroke. SUBJECTS AND METHODS: Two hundred and fifty patients with first-ever ischemic stroke within 24 h of onset were prospectively studied with 3-step diagnoses: 1) symptomatic diagnosis based on the Oxfordshire Community Stroke Project criteria (OCSP), 2) radiological diagnosis (CT or MRI) and 3) etiological diagnosis based on the Lausanne Stroke Registry criteria. RESULTS: Most of the patients with symptoms of total anterior circulation infarcts (TACI), partial anterior circulation infarcts (PACI) and posterior circulation infarcts (POCI) had corresponding lesions on CT or MRI, while only 68% of lacunar infarcts (LACI) patients had small subcortical infarction (SSI). More than 60% of patients with TACI were classified into cardioembolism in the third diagnosis, while the etiology of PACI was either CE or large-artery atherosclerosis (LAA) in equal numbers. Only 58% of LACI patients were classified into small-artery disease (SAD) and 29% of them (30 cases) into LAA, of which 23 patients had lesions other than SSI. The positive predictive value of SAD in the combination of LACI and SSI was 0.78. The etiology of POCI was variable. CONCLUSION: Except for LACI, the symptomatic classification by OCSP corresponds well to the radiological diagnosis. The etiological diagnosis can be predicted by OCSP in TACI and PACI, but it is hard in POCI, and a number of LACI are due to LAA.

Adult↗