Search PubMed⌕ Search

Biomedical subjects

K Kamoi

Publications and source records attributed to K Kamoi.

At least 19 recordsLinked to original sources
PubMed2005

Predominant presence of Streptococcus anginosus in the saliva of alcoholics.

Chronic alcohol consumption is known to be a major risk factor for cancers of the upper aerodigestive tract. The incidence of esophageal cancer (4.4%) in alcoholics is reported to be much higher than that in the Japanese population as a whole (0.0001%). This suggests the presence of specific factors in chronic alcohol consumption-related carcinogenesis. Recently, data showing a significant correlation between Streptococcus anginosus and carcinogenesis in the upper aerodigestive tract have been reported. In this study, the ratio of S. anginosus to oral bacteria in the saliva of 38 alcoholic patients was investigated to determine if there is an association between alcoholic patients and S. anginosus infection. The level of S. anginosus in the saliva from 22 healthy people, 41 esophageal cancer patients, 32 gastritis patients, and 24 periodontitis patients was also investigated and compared to the level in alcoholic patients. In the saliva from esophageal cancer patients, the level of S. anginosus was not significantly different from that of healthy people. The levels of S. anginosus in periodontitis and gastritis patients were also similar. In alcoholics, however, there was an extremely high level of S. anginosus, suggesting that they, rather than healthy people and general esophageal cancer patients, have a high risk for S. anginosus infection.

Adult↗
PubMed2003

Visualization of prostate cancer using dynamic contrast-enhanced MRI: comparison with transrectal power Doppler ultrasound.

This study was designed to assess the efficacy of dynamic contrast-enhanced MRI (DCE-MRI), in comparison with power Doppler ultrasound (PDUS), for visualizing prostate cancer. 111 men suspected of having prostate cancer underwent imaging before undergoing octant biopsy. Subsequently, 31 cancer-positive patients were enrolled in this study. DCE-MRI was obtained using a three-dimensional fast-field echo sequence, which assured wide coverage of the prostate gland. The transrectal PDUS were scored according to the degree of power Doppler flow signals. The time intensity curve types for the DCE-MRI and the PDUS scores were compared with the histopathologic results for each region. The time intensity curves were correlated significantly with PDUS scores (p<0.001). Using PDUS, the overall sensitivity, specificity and accuracy of cancer visualization in peripheral zones were 69%, 61% and 66%, respectively. Using DCE-MRI, the corresponding values were 87%, 74% and 82%. In the inner gland, using PDUS, the overall sensitivity, specificity and accuracy were 68%, 94% and 83%, respectively. Using DCE-MRI, the corresponding values were similar (68%, 86% and 78%). DCE-MRI was significantly more sensitive than transrectal PDUS in peripheral zones (p<0.05). In conclusion, both transrectal PDUS and DCE-MRI can be used to demonstrate hypervascularity in many prostate cancers. DCE-MRI was significantly more sensitive than PDUS for visualizing of prostate cancers without loss of specificity in the peripheral zone.

Aged↗
PubMed2002

Significant decrease of the International Index of Erectile Function in male renal failure patients treated with hemodialysis.

In order to evaluate the erectile function in male renal failure patients treated with hemodialysis (HD), we investigated the International Index of Erectile Function (IIEF) in patients and healthy controls. The subjects were 174 male patients treated with HD, of whom 43 had diabetes mellitus (DM) and the remaining 131 patients did not have DM. The controls were 1133 healthy males. We evaluated the prevalence of erectile dysfunction (ED) using the erectile function (EF) score, which is one of the five domains of the IIEF, in each age group (upto 39 y old, 40-49 y old, 50-59 y old, 60-69 y old). The severity of ED was classified into five categories using EF in each age group. The univariate logistic regression analysis and multiple variate analysis of IIEF in HD patients were performed. The prevalence of ED in HD patients was significantly higher than that in the controls in each age group. The severity of ED in HD patients was also significantly higher than that in the controls in each age group. In the logistic regression analysis and multiple variate analysis of IIEF in HD patients, DM and age were significant risk factors on sexual dysfunction. ED was more prevalent in male renal failure patients treated with HD than in the controls. In the patient group, ED was more prevalent in older DM patients.

Adult↗
PubMed2001

Evaluation of reflux kidney using renal resistive index.

PURPOSE: We clarified the relationships of the renal resistive index, reflux and renal scarring. MATERIALS AND METHODS: The resistive index in the interlobar artery was measured using power Doppler ultrasonography in 22 patients with reflux (reflux group), 13 with postoperative or resolved reflux (previous reflux group) and 20 who served as controls. RESULTS: Resistive index values in 11 kidneys with mid or high grade reflux were significantly higher than in 22 with low grade reflux and in the 40 normal kidneys. The resistive index in the 11 kidneys with reflux and scarring was significantly higher than in the 22 with reflux and without scarring, and in the 40 normal kidneys. The resistive index in the 14 kidneys with previous reflux and scarring was significantly higher than in 12 with previous reflux and without scarring, and in the 40 normal kidneys. Receiver operating characteristics curve analysis in 25 kidneys with and 34 without scarring revealed that a discriminatory resistive index value of 0.71 was optimal for detecting renal scarring. When the resistive index cutoff value was 0.71, there was 76% sensitivity for diagnosing renal scarring, 91% specificity and 85% overall accuracy. CONCLUSIONS: Our results show the possibility that an increased resistive index in kidneys with reflux predicts renal scarring. The resistive index measured with power Doppler ultrasonography may be a noninvasive and useful alternative for screening and following renal scarring.

Adolescent↗
PubMed2001

Gitelman's syndrome first diagnosed as Bartter's syndrome.

A 29-year-old man, who had been treated with potassium, spironolactone and indomethacin for over 9 years, was admitted because of nausea, vomiting, diarrhea and tetany manifestation. At the age of 20, he had been diagnosed as having Bartter's syndrome according to the criteria of the Japanese Ministry of Health and Welfare. Findings on admission were hypokalemia, hypomagnesemia and hypocalciuria. Renal distal fractional reabsorption rates of sodium, chloride and calcium were markedly decreased by administration of furosemide but there was no obvious change with administration of thiazide. These findings indicate that the patient had Gitelman's syndrome rather than Bartter's syndrome.

Adult↗
PubMed2001

[Neoadjuvant hormonal therapy for prostate cancer].

There have been expectations that neoadjuvant hormonal therapy would decrease the rate of positive surgical margins and, therefore, to improve the patient's survival rate after radical prostatectomy for clinically localized prostate cancer. A review of seven prospective randomized studies for clinically localized prostate cancer revealed a significant decrease in the positive surgical margin rate in cases of clinical T2 disease after neoadjuvant hormonal therapy with prostatectomy. However, this treatment did not alter the rate of seminal vesicle invasion or lymph node metastasis after radical prostatectomy. There was no difference in operative blood loss, operating time, complication rate or hospital stay between patients treated with neoadjuvant hormonal therapy and controls. Furthermore, there was no improvement in prostate specific antigen-free survival rate after a maximum of 4 years follow-up. Further research is required to determine the optimal duration of neoadjuvant hormonal therapy and whether this therapy increases the survival rate. Neoadjuvant hormonal therapy before radical prostatectomy is not supported by any outcome at this point and its use remains in the investigational stage.

Antineoplastic Agents, Hormonal↗
PubMed2000

Correlation of histological inflammation in needle biopsy specimens with serum prostate- specific antigen levels in men with negative biopsy for prostate cancer.

OBJECTIVES: To reveal the possible contribution of histological inflammation within the prostate to the abnormal elevation of serum prostate-specific antigen (PSA) levels in patients with needle biopsy negative for prostate cancer. METHODS: We reviewed negative needle biopsy specimens obtained in 93 patients. The degree of acute and chronic inflammation as evaluated histologically was compared with serum PSA levels in conjunction with age and prostate volume. RESULTS: Both age (P <0.01) and prostate volume (P <0.0001) correlated significantly with serum PSA levels and were significantly greater in patients with abnormal serum PSA levels (greater than 4.0 ng/mL) than in those with normal serum PSA levels (4.0 ng/mL or less) (P <0.01). The presence of histological inflammation within the prostate also correlated significantly with serum PSA levels. Multiple regression analysis demonstrated prostate volume to be the only independent determinant of serum PSA levels (P <0.01). In patients with a prostate volume larger than 25 mL, only prostate volume correlated significantly with serum PSA levels (P <0. 05). On the other hand, the degree of acute inflammation as represented by polymorphonuclear leukocyte infiltration was the only parameter correlating significantly with serum PSA levels (P <0.05) in patients with a prostate volume smaller than 25 mL. CONCLUSIONS: Histologically defined acute inflammation within the prostate is a significant contributor to elevated serum PSA levels, especially in patients with small prostates. In the assessment of needle biopsy results negative for prostate cancer, it might be helpful to evaluate the degree of histological inflammation, especially in terms of the necessity of subsequent repeated biopsies.

Aged↗
PubMed2000

Lack of association between an ecNOS gene polymorphism and diabetic nephropathy in type 2 diabetic patients with proliferative diabetic retinopathy.

The development of diabetic nephropathy shows remarkable variation among individuals. Therefore, not only hyperglycemia but also genetic factors may contribute to the development of diabetic nephropathy. The aim of the present study was to examine the contribution of the 27-bp repeat polymorphism in intron 4 of the endothelial constitutive nitric oxide synthase gene (ecNOS4) to the development of diabetic nephropathy. For this purpose, we analyzed this polymorphism in 167 Japanese type 2 diabetic patients with proliferative diabetic retinopathy consisting of 102 patients with diabetic nephropathy (with macroalbuminuria) and 65 patients without diabetic nephropathy (with normoalbuminuria). The genotype and allele frequencies were not significantly different between patients with diabetic nephropathy and those without diabetic nephropathy (ecNOS4 "b/b" 79.4% vs. 84.6%, ecNOS4 "b/a" 20.6% vs. 15.4%, "b" allele 89.7% vs. 92.3%, "a" allele 10.3% vs. 7.7%). We conclude that the ecNOS4 polymorphism does not contribute to the development of diabetic nephropathy.

Aged↗
PubMed2000

Neoadjuvant chemotherapy and hormonal therapy followed by radical prostatectomy: feasibility and preliminary results.

PURPOSE: We assessed the feasibility and efficacy of integrating chemotherapy and androgen ablation with radical prostatectomy in patients with locally advanced prostate cancer. The neoadjuvant approach was adopted because it allows an in situ assessment of antitumoral activity. PATIENTS AND METHODS: Thirty-three patients were enrolled who met the clinical criteria of stage T1-2, Gleason score of >/= 8 or T2b-T2c, Gleason score of 7 and prostate-specific antigen (PSA) level greater than 10 ng/mL (n = 15), or clinical stage T3 (n = 18). Therapy consisted of 12 weeks of ketoconazole and doxorubicin alternating with vinblastine, estramustine, and androgen ablation followed by prostatectomy. The ability of neoadjuvant chemotherapy and hormonal therapy to induce a 20% rate of pT0 in the prostatectomy specimen as well as surgical feasibility were assessed. RESULTS: Chemotherapy complications were comparable to those reported with this regimen previously. No major intraoperative complications occurred. Postoperative complications occurred in 10 (33%) of 30 patients. One patient died at home after discharge (postoperative day 17; no autopsy was performed). Ten (33%) of the 30 patients had organ-confined disease, and 20 (70%) of 30 had extraprostatic extension; 11 (37%) of the 30 had positive lymph nodes. Only five (17%) of 30 exhibited positive surgical margins. All patients achieved an undetectable PSA level postoperatively, and 20 of the surviving 29 patients remain without disease recurrence with a median follow-up of 13 months (range, 9 to 18 months). CONCLUSION: Chemotherapy and androgen ablation followed by radical prostatectomy was feasible in patients with locally advanced prostate cancer. Although the goal of achieving a 20% rate for pT0 status was not achieved, we believe this type of integrated therapeutic strategy should be investigated further for its ability to alter the course of regionally advanced prostate cancer.

Adult↗
PubMed2000

Effects of bisphosphonate on matrix metalloproteinase enzymes in human periodontal ligament cells.

BACKGROUND: The host response is a critical component in the pathogenesis of periodontitis. In fact, the clinical benefits associated with regulating the host response have been demonstrated in studies using several different classes of drugs. Biophosphates are one host-modulating class of drugs that has demonstrated this ability. These drugs are clinically effective at reducing bone resorption and have shown the ability to inhibit host degradative enzymes, specifically the matrix metalloproteinases (MMPs). Therefore, the purpose of this study was to investigate the regulatory effects of a bisphosphonate, tiludronate, on MMP levels and activity in human periodontal cells. METHODS: MMP-1 and MMP-3 were assessed in cultured human periodontal ligament cells treated with a bisphosphonate, tiludronate. Reverse transcription-polymerase chain reaction was used to identify mRNA levels for both enzymes, and also for tissue inhibitors (TIMP-1). Enzyme immunoassay (EIA) and immunocytochemistry were used to assess MMP proteins in these cell cultures. Enzyme activity was assessed using FITC-conjugated substrates and quantitated using spectrophotofluorometry. RESULTS: Tiludronate significantly inhibited both MMP-1 and MMP-3 activity in a concentration-dependent manner. A maximal reduction in activity of 35% was achieved for each of the enzymes at a 10(-4) M concentration. Tiludronate did not have a significant effect on the mRNA levels for MMP-1, MMP-3, or TIMP-1. Similarly, there were no effects noted for either MMP-1 or MMP-3 on the protein level. CONCLUSIONS: This study demonstrates an inhibitory effect of tiludronate on the activity of both MMP-1 and MMP-3. These effects appear to occur without altering either mRNA or protein levels for these enzymes, supporting a possible mechanism of action that involves the ability of bisphosphonates to chelate cations from the MMPs. Furthermore, these results support the continued investigation of these drugs as potential therapeutic agents in periodontal disease.

Analysis of Variance↗
PubMed2000

A comparative analysis of sextant and an extended 11-core multisite directed biopsy strategy.

PURPOSE: The 3 tumor locations unsampled by conventional sextant biopsies that have been identified on composite 3-dimensional reconstruction of 180 radical prostatectomy specimens are the anterior transition zone, midline peripheral zone and inferior portions of the anterior horn in the peripheral zone. We evaluated an 11-core multisite directed biopsy scheme incorporating these alternate areas and conventional sextant biopsies in 362 patients from 2 institutions. MATERIALS AND METHODS: Patients without a prior diagnosis of cancer underwent ultrasound guided 11-core biopsies which included conventional sextant and 3 alternate sites. All specimens were separated for specific location identification. Biopsy was performed in 183 patients at MD Anderson Cancer Center (group 1) and in 179 at Toronto General Hospital (group 2). All group 2 and 54% of group 1 patients (98 of 183) had a prior biopsy negative for cancer. RESULTS: Median prostate specific antigen was higher in group 2 than in group 1 patients (11.5 versus 9.5 ng./ml., p = 0.016). Overall a 33% increase (36 of 110 patients) in cancer detection was observed when biopsy technique included the alternate areas (p = 0.0021). The anterior horn was the most frequently positive biopsy site followed by the transition zone and midline sites. The 11-core technique had significantly better cancer detection rates when digital rectal examination and transrectal ultrasound were normal, and in men with serum prostate specific antigen between 4.1 and 10 ng./ml. CONCLUSIONS: Biopsies of the alternate sites suggested by our simulation studies are feasible and reproducible. This new strategy significantly enhanced (p = 0.0075) prostate cancer detection compared to conventional sextant biopsies in men undergoing a repeat procedure.

Adult↗
PubMed2000

Strategy for repeat biopsy in patients with high grade prostatic intraepithelial neoplasia.

PURPOSE: The finding of high grade prostatic intraepithelial neoplasia in a biopsy specimen without prostate cancer warrants repeat biopsy because of the risk of concurrent cancer. However, to our knowledge the optimal repeat biopsy technique has not yet been defined. We determined the optimal subsequent biopsy strategy for detecting concurrent cancer in patients diagnosed with high grade prostatic intraepithelial neoplasia. MATERIALS AND METHODS: Of 63 men with isolated high grade prostatic intraepithelial neoplasia on initial biopsy 45 underwent repeat biopsy within 1 year. Certain biopsy patterns were used for repeat biopsy, including only the neoplasia site in 8 men, sextant in 12, sextant plus bilateral transition zone in 13 and 11 core multisite directed (sextant, bilateral transition zone, bilateral anterior horn of the peripheral zone and midline peripheral zone) in 12. We compared the location of high grade disease on the initial biopsy with the cancer site on repeat biopsy. RESULTS: Repeat biopsy revealed cancer in 10 of the 45 men (22%), and the sites of high grade prostatic intraepithelial neoplasia and cancer correlated in 6. Cancer was detected at the sextant locations in 9 men. Of the 15 cores positive for cancer 8 were at the original high grade neoplasia site, 6 at a random sextant biopsy site and 1 in the transition zone. High grade disease was discovered bilaterally in 1 man, while prostatic intraepithelial neoplasia and cancer were detected on the same side in the remaining 9. CONCLUSIONS: The optimal repeat biopsy strategy for patients with high grade prostatic intraepithelial neoplasia has not yet been determined but at a minimum it should include targeting the area of known high grade disease and the ipsilateral sextants.

Biopsy↗
PubMed2000

[Ultrasound in urodynamics].

Recent developments of ultrasound imaging have contributed much to the understanding of urodynamics in patients with lower urinary tract symptoms (LUTS). These include ultrasound estimated bladder weight (UEBW), transrectal power Doppler imaging of the prostate and transrectal ultrasonography during voiding (voiding TRUS). UEBW, which is obtained by measuring the thickness of the anterior bladder wall using a 7.5 MHz probe, represents well the degree of bladder hypertrophy caused by obstruction. This parameter is, accordingly, of clinical use in the evaluation of obstruction. The UEBW predicted the presence of obstruction as determined by pressure-flow study with a diagnostic accuracy of 73%. Transrectal power Doppler imaging of the prostate has made it easy to detect prostatic vessels and furthermore to obtain their resistive index (RI). Accumulating data suggest strongly that RI reflects the intraprostatic pressure. More interestingly, RI decreases significantly during voiding in normal subjects but not in patients with benign prostatic hyperplasia. Thus, this method is of particular use in monitoring noninvasively the dynamic change in intraprostatic pressure during voiding. Voiding TRUS makes it possible to monitor the movement of not only the posterior urethra but also the prostate during voiding. Based on our recent study, the anterior fibromuscular stroma (AFMS) seems to contract to open the urethra. Although the physiological function of the AFMS in the prostate remains unknown, AFMS may play a significant role in normal micturition. Due to its noninvasiveness and ease of application, ultrasound imaging would play a vital role in the diagnostic process for patients with LUTS in future.

Humans↗
PubMed1999

Treatment of thyrotropin-secreting pituitary adenomas with octreotide.

Five hyperthyroid patients with TSH-secreting pituitary adenoma were treated with octreotide. Acute administration of octreotide decreased plasma TSH levels in all patients (mean decrease, 50.6 +/- 14%). Treatment with octreotide (25-300 microg/day) for 2-360 weeks resulted in reductions in plasma TSH and alpha-subunit levels in three patients, and serum free thyroxine levels were normalized with concomitant clinical improvements such as disappearance of excessive sweating, tachycardia and finger tremors. In two patients, plasma TSH and free thyroxine levels were initially decreased, but tachyphylaxis occurred 3 and 10 weeks after the initiation of therapy. Mild to marked shrinkage of the tumor was observed 2-50 weeks later in four patients. Shrinkage of the tumor seems to be reversible in one case. Frequent bowel movements and epigastric discomfort occurred in two patient. Somatostatin receptor subtype 2 (sst2) mRNAs were detected in two adenoma tissues studied by RT-PCR. Long-term treatment with octreotide is effective in controlling hyperthyroidism and tumor growth in patients with TSH-secreting pituitary adenoma.

Adenoma↗
PubMed1999

Osmoregulation of vasopressin secretion in patients with the syndrome of inappropriate antidiuresis associated with central nervous system disorders.

To clarify the characteristics of vasopressin (AVP) secretion in patients with the syndrome of inappropriate antidiuresis (SIAD) related to central nervous system disorders, we examined the response of AVP secretion to osmotic stimulus by hypertonic saline infusion and analyzed the possible causative factors in six patients with SIAD associated with head trauma or cerebral infarction. Hyponatremia developed after head trauma in four patients and cerebral infarction in two patients. In all patients the clinical state and laboratory findings fulfilled the criteria for SIAD, which was supported by either nonsuppressible plasma AVP levels or effectiveness of treatments with water restriction, demeclocycline, nonpeptide V2 AVP antagonist or diphenylhydantoin. Although patterns of plasma AVP response to the osmotic stimulus varied, plasma AVP concentrations neither increased nor decreased to undetectable levels with a rise in plasma osmolality. In one patient, plasma AVP levels responded to increasing plasma osmolality when plasma osmolality normalized; in which the threshold and the sensitivity of osmostat were normal. In two other patients, AVP secretion responded to plasma osmolality after the treatment. The changes in AVP secretion were not due to nonosmotic stimuli for AVP release. In conclusion, this study shows that patients with SIAD and central nervous system disorders may have persistent AVP secretion with a loss of hypotonic suppression such as found in patients with adrenal insufficiency or depletional hyponatremia in central nervous system disorders, indicating that careful evaluation is necessary to determine the relationship between persistent AVP secretion and the pathogenesis of hyponatremic disorders.

Aged↗
PubMed1999

Alpha1-adrenergic stimulation induced hypertrophy in protein kinase C down-regulated cultured cardiac myocytes.

To examine whether protein kinase C (PKC) activation is essential for the induction of cardiac myocyte hypertrophy caused by alpha1-adrenergic stimulation, we investigated the hypertrophic effect of phenylephrine in PKC down-regulated and non-treated cultured cardiac myocytes obtained from neonatal Sprague-Dawley rat ventricles. The treatment with 10 nmol/L 12-tetra decanoylphorbol-13-acetate (TPA) for more than 2 hours decreased PKC activity by approximately 80% without marked hypertrophy. Phenylephrine increased [14C] phenylalanine (Phe) incorporation in both TPA non-treated and treated cells, 1.54- and 1.71-fold as large as control, respectively. The cell surface area also enlarged in both groups, 1.67- and 1.74-fold, respectively. Thus, phenylephrine induced the similar grade hypertrophy in cultured cardiac myocytes even when PKC was down-regulated. These results suggest that conventional PKC activation may not be essential for mediating myocyte hypertrophy by alpha1-adrenergic stimulation.

Adrenergic alpha-Agonists↗
PubMed1999

Advances in the application of prostate-specific antigen in the detection of early-stage prostate cancer.

Prostate-specific antigen (PSA) has revolutionized the detection of prostate cancer. PSA-based screening has been shown to be effective in detecting prostate cancer at an early, potentially curable stage; however, this tumor marker is limited by appreciable false-positive and false-negative results. This is especially problematic when the PSA level is in the upper limit of normal (2.5 to 4.0 ng/mL) or the intermediately increased range (4.1 to 10.0 ng/mL). Several PSA-related indexes and assays have been proposed in an attempt to improve the power of PSA in the early detection of prostate cancer: PSA density (PSAD), age-referenced PSA, volume-referenced PSA, PSAD of the transition zone (PSA-TZ), ProstAsure Index, (Global Health Net, Savannah, GA) and percent free PSA. These indexes may improve the sensitivity and specificity of PSA-based screening, facilitating the early detection of prostate cancer and reducing the number of unnecessary biopsies.

Age Factors↗