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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 1,585 records · Page 88Linked to original sources

Dobutamine-stress electrocardiographically gated positron emission tomography for detection of viable but dysfunctional myocardium.

PURPOSE: This study was performed to determine whether low-dose dobutamine stress electrocardiography (ECG)-gated fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) can assess wall motion and identify myocardium without contractile reserve despite preserved FDG uptake. METHODS: Fifty-three patients with myocardial infarction and normal sinus rhythm underwent ECG-gated FDG-PET and transthoracic echocardiography. Wall motion of 10 segments of the left ventricle was graded as normal, hypokinetic, or akinetic/dyskinetic. RESULTS: In 365 (76%) of 480 segments, assessment of wall motion was concordant between the 2 modalities. In 30 patients dobutamine-stress ECG-gated FDG-PET was performed. In 13 (50%) of 26 dysfunctional segments with normal FDG uptake, 16 (36%) of 44 dysfunctional segments with mildly reduced FDG uptake and 12 (25%) of 48 dysfunctional segments with moderately reduced FDG uptake, wall motion was improved by dobutamine infusion. CONCLUSION: Assessment of left ventricular wall motion with ECG-gated FDG-PET is feasible, and dobutamine stress ECG-gated FDG-PET can simultaneously identify metabolic viability and contractile reserve.

Adult↗

Epithelioid trophoblastic tumor (ETT) initially interpreted as cervical cancer.

The epithelioid trophoblastic tumor (ETT) is a rare form of trophoblastic disease and shows a wide spectrum of differential diagnoses and clinical behavior. A 53-year-old woman presented with ETT presumably originated in spontaneous delivery of 25 years ago and was initially diagnosed as cervical cancer on cervical punch biopsy followed by radical hysterectomy. The uterus showed a small tumor restricted to the cavum with no cervical infiltration, resembling ETT in histologic and immunohistochemical features. The difficulties and clues in distinguishing ETT from nontrophoblastic lesions are discussed.

Biopsy, Needle↗

Dobutamine stress electrocardiography-gated Tc-99m tetrofosmin SPECT for detection of viable but dysfunctional myocardium.

BACKGROUND: Technetium-99m-labeled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function by electrocardiography-gated scan. This study was performed to determine whether dobutamine stress electrocardiography-gated tetrofosmin single photon emission computed tomography (SPECT) can identify viable (as defined by positron emission tomography [PET]) but dysfunctional myocardium with contractile reserve. METHODS AND RESULTS: Thirty-five patients with myocardial infarction underwent resting electrocardiography-gated SPECT and fluorodeoxyglucose (FDG) PET. The relative uptakes of tetrofosmin (%tetrofosmin) and FDG (%FDG) were calculated. Wall motion in 9 left ventricular segments was assessed at rest and during dobutamine stress on a 3-dimensional cine-mode display created with automatic left ventricular function analysis software. A total of 129 dysfunctional segments were analyzed. Forty-five (48.9%) of 92 segments with %tetrofosmin of 50% or greater and only 4 (10.8%) of 37 segments with %tetrofosmin less than 50% had contractile reserves (P <.0001). The sensitivity, specificity, and predictive accuracy of %tetrofosmin of 50% or greater for detecting %FDG of 50% or greater were 85.7%, 74%, and 82.9%, respectively. The incidence of the presence of contractile reserve rose with increasing magnitude of %FDG. The sensitivity, specificity, and predictive accuracy of the presence of contractile reserve for detecting %FDG of 50% or greater were 43.9%, 80.6%, and 52.7%, respectively. CONCLUSIONS: Dobutamine stress electrocardiography-gated SPECT can identify viable (as defined by PET) but dysfunctional myocardium with contractile reserve.

Adult↗

A case of multiple ovarian cysts in a prepubertal girl with severe hypothyroidism due to autoimmune thyroiditis.

Some children with profound and long-standing hypothyroidism present with signs of paradoxical sexual maturation. In females, it is characterized by breast development, vaginal bleeding, lack of pubic hair, and delayed bone age. A case of multiple ovarian cysts in a prepubertal girl with severe hypothyroidism due to autoimmune thyroiditis is reported. A 7-year, 8-month-old girl presented with precocious puberty and vaginal bleeding. A pelvic ultrasound revealed markedly enlarged ovaries with numerous cysts which disappeared dramatically after thyroid replacement. When large multiple ovarian cysts with vaginal bleeding are found in a prepubertal girl who has a retarded bone age, the possibility of associated hypothyroidism should be considered. Health care providers should keep this in mind because this constellation of symptoms can be completely reversed with the initiation of thyroid replacement.

Child↗

Invasive adenocarcinoma arising from uterine adenomyosis involving the rectosigmoid colon.

We describe a rare case of invasive endometrioid adenocarcinoma arising from uterine adenomyosis involving the rectosigmoid colon. At laparotomy the uterus was densely adherent to the rectosigmoid colon. The final pathologic study of surgical specimens revealed intact endometrium and endometrioid adenocarcinoma scattered diffusely throughout the posterior myometrium with direct invasion into the rectosigmoid colon. There were numerous adenomyotic foci around the carcinoma. This case emphasizes the fact that biopsy findings from a uterus with adenocarcinoma arising from adenomyosis can be false negative. Physicians should keep in mind the possible existence of malignancies arising from adenomyosis when uterine malignancies are clinically suspected but histologic evaluation fails to confirm the diagnosis.

Aged↗

Erythrocyte water content in spontaneously hypertensive rats and DOCA-salt hypertensive rats.

Intra-erythrocyte water, sodium and potassium contents were measured in spontaneously hypertensive rats (SHR) and deoxycorticosterone acetate (DOCA)-salt rats. In 12 week old SHR, the intra-erythrocyte water content was slightly but significantly lower than that in age-matched Wistar-Kyoto (WKY) rats. SHR also exhibited a significantly lower intra-erythrocyte potassium content, but sodium content tended to be elevated. Although sodium content was not correlated with the water content, potassium content was. In DOCA-salt hypertensive rats, the intra-erythrocyte sodium content was higher than that in age-matched normotensive Sprague-Dawley rats by about 33%, but the water and potassium contents were similar. There were no significant correlations between these parameters. These findings provide no evidence of water retention in erythrocytes from DOCA-salt rat or SHR even though intra-erythrocyte sodium content was increased.

Animals↗

Dissolution of pancreatic stones by oral trimethadione in patients with chronic calcific pancreatitis.

The effect of oral dissolution therapy for pancreatic stones was evaluated in patients with chronic calcific pancreatitis. The anti-epileptic agent trimethadione was given orally to 30 outpatients at a dose of 0.9-1.5 g daily. On plain X-ray films and CT scans of the abdomen, pancreatic stones began to be dissolved around 8 months of treatment, and diminished in size and number or disappeared in 21 patients (70%) during the mean follow-up period of 32 months. The effect of trimethadione treatment on dissolution of stones was not closely related to the aetiology of the disease, distribution and size of stones, previous history of surgical interventions, or the degree of pancreatic dysfunctions. In three patients who stopped this medication of their own accord, pancreatic stones re-increased or reappeared about 6 months later. During trimethadione treatment, impaired exocrine pancreatic function returned to normal in four of nine patients examined, and diabetes mellitus was well controlled by either diet therapy alone or oral hypoglycaemic agents in eight of 10 patients who did not need insulin before trimethadione treatment. Complete relief of pain was noted in 73% of patients during the treatment. Overall gains and no change in bodyweight were observed in 83% of patients. Mild photophobia was the most common side effect, but could be easily overcome by wearing sunglasses. No severe side effects were observed in the liver, kidney, blood or the eyeground. Pancreatic stones in 30 patients not treated with trimethadione neither disappeared nor diminished spontaneously. Trimethadione treatment may be a useful tool for chemical dissolution of pancreatic stones.

Administration, Oral↗

Effect of dimethadione administered intravenously on pancreatic secretion in dogs.

In order to detect both pancreatic excretion of dimethadione (DMO), a weak organic acid, and the effect of pancreatic DMO on secretin-stimulated pancreatic secretion, DMO was given intravenously to dogs with pancreatic fistulae at a dose of 50, 100 and 200 mg/kg. DMO was promptly excreted into pancreatic juice; the concentration decreased exponentially as it did in plasma at the highest dose of the compound. At equilibrium of DMO between pancreatic juice and plasma, the DMO concentration in the juice depended directly on that in plasma; the juice/plasma concentration ratios for DMO exceeded 1.0, ranging from 1.7 to 2.1. Pancreatic DMO caused a small but significant decrease in the water, bicarbonate and sodium secretion at non-equilibrium, and in the bicarbonate secretion at equilibrium. A decrease in the bicarbonate secretion may result largely from the buffer action of bicarbonate on protons provided by the undissociated form of DMO. The sum of both bicarbonate and chloride concentrations in pancreatic juice decreased with the increased DMO concentration in the juice, implying that DMO may compete with the secretion of bicarbonate and/or chloride across the apical membrane of the duct cell. Pancreatic DMO can act as a non-specific inhibitor of pancreatic water and electrolyte secretions.

Animals↗

A case of postirradiation vaginal angiosarcoma treated with recombinant interleukin-2 therapy.

Angiosarcoma of the vagina is an extremely rare neoplasm and is characterized by frequent recurrence and early metastatic spread. Although previous reports emphasized the poor prognosis of this disease, effective treatment strategies have not been adequately stated. We report a case of angiosarcoma of the vagina, in which the diagnosis was made 9 years after intrapelvic irradiation, and recombinant interleukin-2 (rIL-2) therapy could be effective to suppress the development of distant metastasis. We recommend rIL-2 therapy in combination with irradiation as a palliative therapeutic option for vaginal angiosarcoma when the tumor is inoperable or the patient refuses to undergo surgery. Although vaginal angiosarcoma is an extremely rare condition, its possibility should be borne in mind when finding a vaginal mass in a previously irradiated patient.

Antineoplastic Agents↗

A case of alpha-fetoprotein-producing adenocarcinoma of the endometrium with a hepatoid component as a potential source for alpha-fetoprotein in a postmenopausal woman.

Although case reports of alpha-fetoprotein (AFP)-producing adenocarcinoma other than hepatocellular carcinoma have gradually increased in number, AFP-producing adenocarcinoma of the endometrium is very rare. The patients universally complain of abnormal vaginal bleeding. The patient presented with complaints of epigastric discomfort. No vaginal bleeding was observed. Serum AFP concentration was 453 ng/mL, and lens culinaris agglutinin-reactive AFP percentage of total AFP was increased to 67%. Radiologic imaging and endoscopy did not provide evidence of any primary carcinoma in the liver and gastrointestinal tract. To investigate the unknown origin of high AFP, Pap smear of the endometrium followed by fractional curettage was performed and revealed adenocarcinoma of the endometrium. Radical hysterectomy with pelvic lymph node dissection and partial omentectomy was performed. Histologic study showed a mixture of major AFP-negative endometrioid adenocarcinoma and minor medullary proliferation of the AFP-positive hepatoid adenocarcinoma cells with eosinophilic cytoplasm and hyaline globules. After the surgery followed by four courses of weekly carboplatin and paclitaxel administration, serum levels of AFP dropped into normal range. The possible existence of AFP-producing adenocarcinoma of the endometrium should be considered in a postmenopausal woman even if there is no vaginal bleeding, when AFP-producing tumor is clinically suspected and the imaging studies fail to confirm the diagnosis.

Carcinoma, Endometrioid↗

Role of nitric oxide in pathogenesis of aspirin-induced gastric mucosal damage in rats.

We examined the effect of NO synthase inhibitor on the functional and ulcerogenic responses to aspirin (ASA) in rat stomach. The animals were given ASA (20-80 mM) orally with or without HCl (10-50 mM) and killed 2 h later. NG-nitro-L-arginine methyl ester (L-NAME) was given i.v. 5 min before aspirin. In the functional study, a rat stomach was mounted on an ex vivo chamber under urethane anesthesia, perfused with saline, and transmucosal potential difference (PD), luminal pH, acid secretion and mucosal blood flow (GMBF) were measured simultaneously. ASA alone caused gastric damage in a dose-related manner; mostly nonhemorrhagic lesions. Pretreatment with L-NAME worsened such lesions and caused severe hemorrhagic lesions. Coadministration of HCl with ASA also potentiated gastric lesions in a concentration-dependent manner, changing nonhemorrhagic into hemorrhagic damage, and the worsening effect of L-NAME disappeared when 80 mM ASA was given together with HCl at >20 mM. In chambered stomachs, the mucosal application of ASA (80 mM, 30 min) caused a marked reduction in PD and a slight decrease in acid secretion, with minimal change in GMBF. L-NAME blocked the reduced acid response following ASA and caused stimulation of acid secretion with no effect on PD and GMBF. These effects of L-NAME were all antagonized by coadministration of L-arginine and significantly mitigated by sensory deafferentation or pretreatment with cimetidine or FPL-52694. These results suggest that (1) intragastric administration of ASA causes a release of NO, which reduces the development of hemorrhagic lesions by decreasing acid secretion, and (2) L-NAME worsens gastric damage by increasing acid secretion in ASA-treated stomachs, the process being dependent on endogenous histamine and sensory neurons.

Animals↗

Stimulatory effect of nitric oxide on bicarbonate secretion in bullfrog duodenums in vitro.

The effect of nitric oxide (NO) on HCO-3 secretion was examined in vitro using an isolated preparation of bullfrog duodenum. The tissue was bathed in unbuffered Ringer's solution gassed with 100% O2 on the mucosal side and HCO-3 Ringer's solution gassed with 95% O2-5% CO2 on the serosal side. The HCO-3 secretion was measured by the pH-stat method using 2 mmol/l HCl as the titrant to keep the mucosal pH at 7.4. (+/-)-(E)-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamine (NOR3) was used as a NO donor and added to the serosal solution. To analyze the NOR3 action on HCO-3 secretion, the effects of dibutyryl adenosine-3',5'-cyclic monophosphate (dbcAMP), dibutyryl guanosine-3',5'-cyclic monophosphate (dbcGMP), methylene blue, and indomethacin on the HCO-3 response were also examined. NOR3 (1x10(-4) and 3x10(-4) mol/l) caused an increase in HCO-3 secretion in a dose-dependent manner, and this effect appeared with an about 30-min time lag, reaching the level of 1.5-2.5 times greater than basal values at 1-2 h later. Both dbcAMP (1x10(-3) mol/l) and dbcGMP (1x10(-3) mol/l) also caused a significant increase in HCO-3 secretion in bullfrog duodenums in vitro, although the onset of the HCO-3 response to dbcGMP was delayed as compared to the former. The stimulatory action of NOR3 on duodenal HCO-3 secretion was significantly attenuated by methylene blue (5x10(-5) mol/l) and indomethacin (1x10(-5) mol/l), the latter also inhibiting the HCO-3 response to dbcGMP. The release of prostaglandin E2 in the serosal solution was significantly increased after addition of NOR3 (3x10(-4) mol/l) and dbcGMP (1x10(-3) mol/l) in an indomethacin-sensitive manner. These results suggest that the NO donor increases duodenal HCO-3 secretion in vitro, and this action of NO donor is cGMP-dependent and mediated by endogenous prostaglandins. Duodenal HCO-3 secretion may be regulated locally by NO/cGMP in addition to prostaglandin/cAMP.

Animals↗

Increased susceptibility of diabetic rat gastric mucosa to food deprivation during cold stress.

BACKGROUND: We investigated the mechanisms responsible for the increased susceptibility of diabetic rat gastric mucosa to damage inflicted by overnight food deprivation (18 h) and its worsening by the cold restraint stress (4 degrees C, 3 h). METHODS: Gastric damage was measured in fasted animals, some of which were rendered diabetic by a single intraperitoneal injection of streptozotocin (STZ; 70 mg/kg) 5 weeks before experiments (STZ 5W). RESULTS: STZ 5W rodents showed a number of hemorrhagic lesions in corpus mucosa (26. 8 +/- 5.2 mm(2)) which could be prevented by insulin or nitric oxide synthase (NOS) inhibitors: aminoguanidine or L-NAME (N(omega)-nitro-L-arginine methyl ester). Mucosal injury was further aggravated by low temperature (51.1 +/- 7.8 mm(2)), the damage ameliorated by insulin, aminoguanidine, or L-NAME. The salutary actions of L-NAME were L-arginine sensitive. Low temperature and L-NAME did not significantly influence the gastric secretory parameters in normal rats. On the other hand, L-NAME and aminoguanidine counteracted the attenuation of gastric juice acidity and acid output in STZ 5W rodents. Blood plasma nitrite and nitrate levels and outputs in gastric juice were augmented in STZ 5W animals in comparison to controls. The total activities of NOS including inducible NOS but not constitutive NOS were markedly enhanced by fasting and cold restraint in gastric mucosa of STZ 5W animals (2.2- and 3.7- or 2.4- and 17.9-fold respectively). CONCLUSIONS: Stressful stimuli, such as food bereavement and cold challenge contribute to the elevated susceptibility of diabetic gastric mucosa to damage, even though the main aggressive factor, i.e., gastric acid secretion, is attenuated. The enhanced production of nitric oxide by inducible NOS during food deprivation and cold exposure seems to play an important role in gastric mucosal integrity disturbances during diabetes.

Animals↗

Expression of ETS-1 is correlated with urokinase-type plasminogen activator and poor prognosis in pulmonary adenocarcinoma.

Urokinase-type plasminogen activator (u-PA) is known to be involved in proteolytic degradation of extracellular matrix during carcinoma invasion. Similarly Ets-1, a transcription factor, is also known to be important for carcinoma progression, and has been reported to interact with the u-PA gene enhancer. We used immunohistochemistry to analyze the relationship between Ets-1 and u-PA protein expression in patients with pulmonary adenocarcinoma. A significant association was found between Ets-1 expression and u-PA expression. The Ets-1 expression was correlated with T factor, lymph node metastasis and stage. Kaplan-Meier survival analysis revealed that survival times were longer in patients with Ets-1-negative tumors than in patients with Ets-1-positive tumors. Our results suggest an important role for Ets-1 in tumor progression, and the correlation with u-PA protein expression serves as an important prognostic factor in pulmonary adenocarcinomas.

Adenocarcinoma↗

Overexpression of p53 protein and proliferative activity in colorectal adenoma.

Overexpression of p53 was studied immunohistochemically in colorectal tumors. We found p53-positive cells in 17 (58.6%) of 29 specimens of cancer in adenoma. Expression of p53 protein was detected in the nuclei of the tumor cells. We also found p53-positive cells in 7 (7.1%) of 99 specimens of adenoma. p53 immunoreactivity for severe dysplasia was higher than that for mild or moderate dysplasia. p53 expression in adenomas was restricted to a few glands, and the proliferating-cell nuclear antigen (PCNA)-positive rate for the p53-positive glands was significantly higher than that for p53-negative glands. The results suggested that the p53-positive glands might have high growth fractions, and that immunohistochemical detection of p53 expression in tubular adenomas might contribute to identifying the potential for malignant transformation.

Adenoma↗

Rheological properties of middle ear effusions from children with otitis media with effusion.

Freshly harvested middle ear effusions (MEE) were collected from children with otitis media with effusion. Both elasticity (G') and viscosity (eta') of the MEE were determined by an oscillating sphere magnetic rheometer and compared with transportability of the MEE on mucus-depleted frog palates. A maximum value of transport was obtained at G' of about 20 dyne/cm2 (at 1 Hz), and below this value there was a significant positive correlation between the transport rate and log G'. Above 20 dyne/cm2, the negative correlation between the transport rate and log G' was significant. This shows there is a sharp increase in transport with increase in G' up to 20 dyne/cm2, and at the higher value of G' there is a slow decrease in transport with increasing G'. A similar significant correlation between the transport rate and log eta' was observed.

Adolescent↗

Hearing impairment in relation to viscoelasticity of middle ear effusions in children.

Both dynamic viscosity (eta') and elasticity (G') of middle ear effusion were measured with an oscillating sphere magnetic rheometer and compared with the degree of conductive hearing loss in 65 ears of 40 children. There was a significant correlation between eta' and the magnitude of the air-bone gap at 500 and 1,000 Hz, but there was no significant correlation between eta' and the magnitude of the air-bone gap at 2,000 or 4,000 Hz. No significant correlation was noted between G' and the magnitude of the air-bone gap at 500, 1,000, 2,000, or 4,000 Hz. These results indicate that the eta' of middle ear effusion has an effect on the amount of hearing impairment at frequencies below 1,000 Hz.

Child↗