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K Okubo

Publications and source records attributed to K Okubo.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Pulmonary thromboembolism after videothoracoscopic excision of a mediastinal tumor; report of a case].

We experienced a case of pulmonary thromboembolism after videothoracoscopic excision of a mediastinal tumor. A 57-year-old woman underwent videothoracoscopic excision of an upper mediastinal tumor, which was pathologically diagnosed as neurilemmoma. On the first postoperative day, she suddenly suffered from fatigue and blood-gas analysis showed hypoxemia. No abnormal shadow was seen on chest X-ray. Lung perfusion scintigram showed multiple embolism. She was treated with anticoagulants and recovered well. We should pay attention to the possibility of pulmonary thromboembolism after video-assisted thoracic surgery as well as thoracotomy, especially when patients have risk factors for pulmonary thromboembolism.

Anticoagulants↗
PubMed2002

Impact of calcium antagonists on bleeding time in patients with chronic renal failure.

Haemorrhagic diathesis develops in chronic renal failure, in which calcium antagonists are used widely as antihypertensive agents. Although calcium antagonists are reported to impair platelet function, it has not been examined whether calcium antagonists alter bleeding time. The present study was conducted to clarify whether calcium antagonists affect bleeding time in chronic renal failure. Patients with chronic renal failure without and with calcium antagonists were enrolled (n = 156), and bleeding time (Ivy's method) as well as blood parameters (BUN, creatinine, platelet counts, and haemoglobin) were compared in patients with normal and prolonged bleeding time. Among patients not taking calcium antagonists (n = 34), three cases manifested prolonged bleeding time, whereas abnormal bleeding time was observed in 31 patients out of 122. Positive correlations were observed between bleeding time and BUN in both calcium antagonist-untreated (r = 0.46) and -treated groups (r = 0.25). The odds ratio for prolongation of bleeding time in patients taking calcium antagonists was 3.52 (95% CI, 1.01-12.33). In 12 calcium antagonist-treated patients with prolonged bleeding time, the withdrawal of calcium antagonists markedly shortened bleeding time (from 11.3 +/- 0.8 to 5.4 +/- 0.8 min, P < 0.05, n = 12). In contrast, in the additional group (n = 9), the continued treatment with calcium antagonists had no effect on bleeding time (from 11.7 +/- 0.9 to 10.0 +/- 1.0 min). Despite the inhibitory effect of calcium antagonists on bleeding time, no clinically serious events associated with haemorrhagic diathesis developed. In conclusion, calcium antagonists prolong bleeding time in patients with chronic renal failure. The subclinical (laboratory) effect of calcium antagonists however is not necessarily associated with haemorrhagic events of clinical significance.

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PubMed2002

Expression profile of active genes in the human pituitary gland.

To characterize transcripts abundantly expressed in the human pituitary gland in general as well as to isolate novel transcripts expressed specifically in this gland, we generated an expression profile of the active genes transcribed in it. A total of 1015 randomly collected 3prime prime or minute expressed sequence tags (ESTs) (gene signatures, GSs) were grouped into 527GS species. The results showed the relative expression levels of genes in the pituitary gland. The genes comprising more than 1% of total mRNA were prolactin, growth hormone and chromogranin B genes. When known genes were categorized, the genes for pituitary hormones were the most actively transcribed, followed by the genes for ribosomal proteins, nuclear proteins and secretory granule proteins. Through comparison of this gene expression profile with the BodyMap database containing profiles generated from 63 other human tissues, we obtained 11 genes which appeared to be specifically expressed in the pituitary gland. In addition to the eight known genes, we identified three novel pituitary-specific transcripts which encode putative proteins: pituitary gland specific factor 1a (PGSF1a), PGSF1b and PGSF2. This expression profile method is a novel approach to the isolation of pituitary-specific genes that may have important functions.

Amino Acid Sequence↗
PubMed2002

Emergent pneumonectomy for hemoptysis in a patient with previous thoracoplasty.

Hemoptysis is a life-threatening episode of respiratory disease. By means of every possible treatment, hemostasis should be obtained to secure the airway as well as to prevent blood loss. We describe an emergency pneumonectomy for massive hemoptysis from destroyed lung in a patient with previous thoracoplasty. After the prolonged ventilation support postoperatively, the patient with compromised lung function recovered well.

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PubMed2002

[Concomitant lobectomy for lung cancer under intraaortic balloon pumping and coronary bypass grafting].

A 71-year-old man was admitted because of an abnormal shadow on the chest X-ray film. Chest computed tomography (CT) revealed a tumor in the right upper lobe. The diagnosis of lung cancer was made by transbronchial lung biopsy. He had suffered an infarction of the inferior myocardial wall at the age of 55 years. Preoperative coronary angiography revealed total occlusion of segment 1, 75% stenosis of segments 5 and 6, and 90% stenosis of segment 13. Since these coronary lesions could cause perioperative and postoperative myocardial infarction, the patient was scheduled to undergo surgery of both the heart and lung in a one-stage operation. Under intraaortic balloon pumping (IABP), we performed a right upper lobectomy of the lung, and coronary artery bypass grafting with cardiopulmonary bypass through median sternotomy. During the lobectomy and first postoperative day, a stable circulation was achieved with IABP. The postoperative course was uneventful. At present, that is 33 months after the operation, the patient presents no sighs of recurrence of lung cancer and has not suffered any anginal attack during follow-up. Lung cancer and coronary artery disease can be treated simultaneously by this procedure.

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PubMed2001

Racial differences in cellular composition of benign prostatic hyperplasia.

BACKGROUND: The present study was designed to compare the cellular composition of benign prostatic hyperplasia (BPH) in Caucasian-American (CA), African-American (AA), and Japanese (JP) men. METHODS: Biopsy specimens of the prostate were obtained from 15 men of each racial group with a prostate-specific antigen (PSA) of 4.1-10.0 ng/mL. The stained cores were quantitatively analyzed for the percentage of the area with different cellular composition (stroma (S), epithelium (E), epithelial lumen (L), and glandular component (E + L = G)), using computer-assisted color imaging. RESULTS: The mean percent area density of S, E, and L in the prostate of CA men was 84.2, 12.1, and 3.8%, respectively; for AA, 84.4, 12.4, and 3.2%; for JP, 77.4, 15.2, and 7.5%. The S/E ratio is significantly lower in JP than in CA men. The S/G ratio is significantly lower in JP than in CA and AA men. Overall, JP contained more glandular lumen and less stromal component than that of CA and AA. CA and AA showed no significant difference in cellular composition. CONCLUSIONS: The present study demonstrated the differences in cellular composition of BPH among the three races. This cellular composition divergence may account for previously observed racial differences in PSA, PSA density, and the incidence of clinical BPH.

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PubMed2001

Isolation of novel heart-specific genes using the BodyMap database.

Two novel heart-specific genes, C3orf3 (chromosome 3 open reading frame 3) and MMGL (myomegalin-like), were isolated using BodyMap, a gene expression database based on site-directed 3' expressed sequence tags (3'-ESTs) which were collected from nonbiased cDNA libraries of various tissues. The cDNA of C3orf3 was 1667 bp and was composed of 12 exons within a 10-kb-long genomic sequence. MMGL consisted of 8 exons within a genomic sequence of over 70 kb, leading to four alternatively spliced transcripts. Both genes were strongly expressed in heart and also in skeletal muscle. C3orf3 and MMGL were mapped to 3p22 and 1q1, respectively. Subcellular localizations of their putative proteins were determined as being in the cytoplasm for C3orf3 and in the cytoplasm and nucleus for MMGL. This study showed that BodyMap is a useful database for the isolation of tissue-specific genes.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Functional imaging of the brain in sedated newborn infants using near infrared topography during passive knee movement.

Near infrared topography was used for functional imaging of the sensorimotor cortex of newborn infants during passive knee movement under sedated sleep. Contralateral knee movement caused a marked increase in oxyhemoglobin and total hemoglobin from the baseline values at almost all locations in the primary sensorimotor area of all neonates and a decrease in local deoxyhemoglobin in six of seven neonates. During ipsilateral knee movement, oxyhemoglobin and total hemoglobin showed slighter changes at a few locations, equal to 30% (mean) and 29% (mean) of the changes that occurred with contralateral stimulation, respectively. The mean times corresponding to maximal changes were 11.9 s for oxyhemoglobin and 19.1 s for deoxyhemoglobin, demonstrating that oxyhemoglobin has a much faster response than does deoxyhemoglobin.

Brain Mapping↗
PubMed2001

Volume-weighted mean nuclear volume predicts tumor biology of clinically organ-confined prostate cancer.

BACKGROUND: Estimates of volume-weighted mean nuclear volume (MNV) are the only means by which unbiased estimates of three-dimensional parameters can be obtained from a single two-dimensional section, with stereological methods. The present study was conducted to elucidate the role of MNV in predicting tumor biology for patients treated with radical prostatectomy. METHODS: A retrospective prognostic study of 71 patients with T1/T2 disease, treated with radical prostatectomy alone, was performed. MNV was estimated using biopsy specimens based on a stereological method, and was compared with other preoperative clinical variables. For patients with prostate-specific antigen (PSA) failure, we determined the correlation of MNV with PSA doubling time (PSA DT) which was calculated using PSA values obtained with an ultrasensitive assay. RESULTS: Mean MNVs for pathologically organ-confined and non-organ-confined tumors were 198.9 and 236.3 microm3, respectively; this difference was significant (P = 0.0364). Univariate analysis showed that PSA, MNV, and Gleason score were significant predictors of prognosis (P = 0.0126, 0.0148, and 0.0375, respectively). Multivariate analysis revealed that MNV and preoperative PSA were powerful independent predictors of prognosis (P = 0.0160 and P = 0.0147, respectively), but the Gleason score was not correlated with prognosis (P = 0.4120). For patients with PSA failure, PSA DT was significantly correlated with MNV (r = -0.597, P = 0.0099). When these patients were classified using median PSA DT at 6 months into two groups, MNV was significantly greater in PSA rapid-riser group than in the slow-riser group (P = 0.0008), but no differences were observed between these groups in PSA, the Gleason score, or cancer volume. CONCLUSIONS: The findings of the present study suggest that MNV is a powerful predictor of PSA failure for patients with clinically organ-confined disease treated with radical prostatectomy. More importantly, they suggest that MNV can be a useful new parameter for prediction of tumor biology for patients with PSA failure after radical prostatectomy.

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PubMed2001

BodyMap incorporated PCR-based expression profiling data and a gene ranking system.

BodyMap is a human and mouse gene expression database that is based on site-directed 3'-expressed sequence tags generated at Osaka University. To date, it contains more than 300 000 tag sequences from 64 human and 39 mouse tissues. For the recent release, the precise anatomical expression patterns for more than half of the human gene entries were generated by introduced amplified fragment length polymorphism (iAFLP), which is a PCR-based high-throughput expression profiling method. The iAFLP data incorporated into BodyMap describe the relative contents of more than 12 000 transcripts across 30 tissue RNAs. In addition, a newly developed gene ranking system helps users obtain lists of genes that have desired expression patterns according to their significance. BodyMap supports complete transfer of unique data sets and provides analysis that is accessible through the WWW at http://bodymap.ims.u-tokyo.ac. jp.

Animals↗
PubMed2001

An expression profile of active genes in human conjunctival epithelium.

The purpose of this study was to describe the quantitatively and qualitatively genes expressed in in vivo human conjunctival epithelium. A cDNA library was created from human conjunctival epithelial cells obtained from 38 normal eyes by brush cytology. Poly A(+)RNA isolated from these cells was used as a template for cDNA synthesis by the vector-priming method. A 3'-directed cDNA library consisting of the cDNA moiety covering the poly A(+)RNA tail through the nearest Mbo I site was constructed and transformed into Escherichia coli. Inserts in 933 randomly chosen clones were sequenced. The resulting sequences were compared to determine frequency of appearance in the library, and to establish an expression profile of genes in the conjunctival epithelium. The sequences were sent to GenBank for gene identification. The result was an expression profile of active genes reflecting their relative abundance in the conjunctival epithelial mRNA population. The expression profile of human conjunctival epithelium showed that the most abundant gene transcript in human conjunctival epithelium was that for cytokeratin 13. Altogether 102 genes were found to be very active, including beta-2 microglobulin, lipocortin I and insulin-like growth factor binding protein-3. The gene expression profile of the conjunctival epithelium reflects the unique properties and functions of this tissue. Comparison of this expression profile with that obtained from corneal epithelium discloses clear differences and helps us better understand the physiology and pathophysiology of the ocular surface in humans.

Adult↗
PubMed2001

Gonadotropin-releasing hormones (GnRHs) in a primitive teleost, the arowana: phylogenetic evidence that three paralogous lineages of GnRH occurred prior to the emergence of teleosts.

Multiple molecular forms of gonadotropin-releasing hormone (GnRH) are present in a single vertebrate species. To extend the knowledge on GnRH evolution and the number of GnRH forms in one organism, GnRH cDNAs have been isolated and characterized from one of the most primitive teleosts, the arowana Scleropages jardini. This species had two molecular forms of GnRH: salmon-type GnRH (sGnRH) and chicken-II-type GnRH (cGnRH-II). Sequence comparison between the prepro-GnRHs of the arowana and those of other teleosts indicated that sGnRH represented a paralogue separate from any other forms of GnRH. Consistently, subsequent phylogenetic analysis showed that known forms of GnRH in teleosts fell into three paralogous lineages: sGnRH alone on one lineage, cGnRH-II on another, and many other forms on the other. These results suggest that an ancestral GnRH gene duplicated twice prior to the emergence of teleosts and, therefore, that teleosts, and probably also tetrapods, would possess three paralogous forms of GnRH in individual brains.

Amino Acid Sequence↗
PubMed2001

Estimation of regional cerebral blood flow distribution in infants by near-infrared topography using indocyanine green.

Near-infrared topography with indocyanine green was used to measure regional cerebral blood flow (rCBF) in the temporal lobes of infants. The mean rCBF in infants without neural abnormality was 14.5 +/- 3.1 ml/100 g/min, and the rCBFs in the fronto-temporal, temporal, and occipito-temporal regions were 15.1 +/- 3.9, 15.4 +/- 3.3, and 14.6 +/- 3.3 ml/100 g/min, respectively. Moreover, in one asphyxiated infant with infarction and one infant with subdural and intracerebellar hemorrhage, it was demonstrated that the area of defective blood flow could be detected as well as it can by SPECT. This technique makes it possible to estimate rCBF distribution in infants at the bedside. Thus, in the future, evaluation of various neonatal illnesses should be feasible.

Asphyxia Neonatorum↗
PubMed2001

Angiosarcoma of the breast: report of a case and its findings of MRI.

A 67-year-old woman with angiosarcoma of the left breast is presented. Physical findings showed a hard mass in the left breast with skin discoloration and erythema. Mammography showed a high density shadow in the mass without microcalcification and spicula. On ultrasonography, a hypoechoic mass with an ill-defined boundary was detected. On MRI, the tumor had low signal intensity on T1-weighted images, and higher signal intensity on T2-weighted images. MRI with Gd-DTPA images showed higher signal intensity on T1-weighted images with relatively lower intensity in the central area of the tumor. The artery supplying the tumor derived from the left inner thoracic artery and was visualized on three-dimensional dynamic MRI angiography. Initially misdiagnosed as inflammatory breast cancer, an arterial injection of CPA (100 mg) and 5-FU (500 mg) had been performed preoperatively. The definitive diagnosis of angiosarcoma was established by intraoperative frozen section examination. She underwent modified radical mastectomy and is now free of recurrence. This case emphasizes the difficulties in the clinical diagnosis of angiosarcoma of the breast.

Aged↗
PubMed2001

Excision of an invasive thymoma: a cure for ulcerative colitis?

Thymoma is often associated with other diseases, including autoimmune diseases and endocrine disorders. Ulcerative colitis is a nonspecific inflammatory disease and is thought to be an immune-mediated disorder; however, coincidence of thymoma and ulcerative colitis is rare. We treated a 51-year-old woman with invasive thymoma and ulcerative colitis. After excision of the invasive thymoma with partial resections of pericardium, left lung, brachiocephalic vein, and left phrenic nerve, the ulcerative colitis was cured.

Colitis, Ulcerative↗
PubMed2001

Dynamic endorectal magnetic resonance imaging for local staging and detection of neurovascular bundle involvement of prostate cancer: correlation with histopathologic results.

OBJECTIVES: To assess the staging accuracy and detection of neurovascular bundle involvement by dynamic subtraction contrast-enhanced endorectal magnetic resonance imaging (MRI) in patients with localized prostate cancer. METHODS: In 38 patients with biopsy-proven prostate cancer, endorectal MRI was performed on a 1.5-Tesla magnetic resonance system using the dynamic technique with gadolinium-diethylenetriaminepentaacetic acid bolus enhancement. Two radiologists prospectively assessed the tumor involvement, localization, capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement. All patients subsequently underwent radical prostatectomy, and the MRI findings were correlated with the histopathologic results. RESULTS: The overall accuracy of detecting cancer localization in the prostate was 72%. The detection of involvement in the peripheral zone had an 80% accuracy rate, but for lesions in the transition zone, the rate was 63%. The sensitivity and specificity of tumor detection was 81% and 79% for peripheral zone cancers and 37% and 97% for transition zone cancers, respectively. The accuracy rate, was 84%, 97%, and 97% for the detection of capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement, respectively. CONCLUSIONS: Prostatic MRI with an endorectal surface coil using the dynamic technique more accurately detected tumor localization, capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement than previously reported methods. The detection of tumor localization was more accurate in the peripheral zone than in the transition zone. This technique may be useful for the selection of patients for radical prostatectomy and, particularly, for identifying candidates for nerve-sparing surgery.

Aged↗
PubMed2001

Microwave thermotherapy for benign prostatic hyperplasia with the Dornier Urowave: response durability and variables potentially predicting response.

OBJECTIVES: To evaluate the clinical efficacy and durability of transurethral microwave thermotherapy (TUMT) in the treatment of benign prostatic hyperplasia. The clinical variables useful in predicting outcome were identified. METHODS: From October 1996 to March 2000, 58 patients with symptomatic benign prostatic hyperplasia were treated with TUMT using the Urowave device. Treatment outcome was evaluated by the International Prostate Symptom Score (IPSS), quality-of-life assessment score, and urodynamic investigation. The patients were divided into those having a good and poor response on the basis of the degree of IPSS decrease at 3 months. RESULTS: The mean IPSS significantly decreased from 19.2 at baseline to 13.3 at 3 months (P <0.0001). The mean quality-of-life score changed from 4.6 at baseline to 2.9 at 3 months (P <0.0001). No statistically significant differences in peak flow rate, postvoid residual volume, Schäfer's obstruction scale, or detrusor pressure at peak flow were noted before or after TUMT. The pretreatment IPSS of the good response group was significantly higher than that of the poor response group (P=0.017). A more significant difference was obtained for the obstructive score (P = 0.002), and no difference was observed in the irritative score (P = 0.631). The Schäfer grading scale score of the good response group was significantly smaller than that of the poor response group (P = 0.047). CONCLUSIONS: TUMT with the Urowave was effective in eliminating symptoms associated with benign prostatic hyperplasia, but did not markedly improve the objective voiding parameters. Patients with urodynamically less obstructive symptoms but subjectively more obstructive symptoms are therefore probably good candidates for TUMT.

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