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Biomedical subjects

T Okai

Publications and source records attributed to T Okai.

At least 37 records · Page 2Linked to original sources
PubMed2001

Clinical management of intraductal papillary mucinous tumors of the pancreas based on imaging findings.

The aim of this study was to assess the imaging findings of pathologically proven intraductal papillary-mucinous tumors of the pancreas and the natural history of follow-up cases, and to optimize the therapeutic management of patients with these tumors according to their imaging findings. All nine patients with main duct type tumors were histologically diagnosed as having adenocarcinoma or adenoma, with no hyperplastic lesion. The images failed to discriminate between the two histologic types. In 26 patients with branch duct type tumors, all but one with intraductal mural nodules or tumors of > or = 30 mm had adenocarcinoma or adenoma, regardless of the caliber of the main duct. Of the nine patients with tumors < 30 mm and no mural nodules. three had adenoma, and six had hyperplasia. All of four patients had hyperplasia, with the additional caliber of the main duct being < 6 mm. In a series of 23 cases in which the patient was followed-up, no apparent progression was found in 17 patients who had no mural nodules and tumors of < 30 mm. Given these results, patients with main duct type tumors, and those with branch duct type tumors showing mural nodules or a tumor diameter of > or = 30 mm, are at high risk of developing neoplasms, including adenocarcinoma, for which surgical resection should be considered, whereas those patients with tumors < 30 mm and no mural nodules can be followed.

Adenocarcinoma↗
PubMed2001

Usefulness of supernatant of pancreatic juice for genetic analysis of K-ras in diagnosis of pancreatic carcinoma.

AIMS: To ascertain whether analysis of K-ras mutations at codon 12 (KRM) in the supernatant of pure pancreatic juice (PPJ) is more useful for the diagnosis of pancreatic carcinoma (PCa) than that in sediment, the authors analyzed KRM in DNA extract from not only the sediment but also the supernatant of PPJ and compared the results. METHODOLOGY: PPJ was collected endoscopically from 19 patients with PCa and 25 patients with chronic pancreatitis (CP). DNA was extracted from the supernatant and the sediment of PPJ. Mutant allele-specific amplification (MASA) was performed for KRM analysis with the DNA extracts from these samples. RESULTS: The incidence of KRM in the supernatant of PPJ was 89% (17 of 19) in patients with PCa and 28% (7 of 25) in patients with CP, whereas that in the sediment was 79% (15 of 19) in patients with PCa and 20% (5 of 25) in patients with CP. Although there was no significant difference in KRM incidence between supernatant and sediment, the positive rate of KRM was higher in the former. Additionally, with regard to the PCa cases, KRM were found in the supernatant alone in four cases and in the sediment alone in two cases. Consequently, by a combination assay, all of the patients with PCa showed KRM in either the supernatant or sediment of PPJ. Although there was no relation between the incidence of KRM in PPJ and the location and size of tumor, and clinical stage of carcinoma in the patients with PCa, two patients with clinical stage I disease showed KRM in the supernatant. CONCLUSION: These results suggest that the positive rate of KRM in the supernatant is not lower than that in the sediment, and simultaneous analysis of KRM in the supernatant and sediment of PPJ enhances the genetic diagnosis of PCa.

Adolescent↗
PubMed2001

Rapid detection of chromosome aneuploidies by prenatal interphase FISH (fluorescence in situ hybridization) and its clinical utility in Japan.

OBJECTIVE: The purpose of this study was to assess the accuracy, informative rate, detection rate, and clinical utility of prenatal interphase fluorescence in situ hybridization (FISH) analysis of amniotic fluid samples from Japanese women. METHODS: Amniotic fluid specimens from 2,639 Japanese women were received for prenatal interphase FISH and chromosome analysis. A questionnaire was designed to evaluate FISH clinical utility by collaboration sites. RESULTS: Based on 2,319 tested samples, the accuracy (100%), informative (94%), and detection (87.6%) rates were all high. The accuracy (100%), informative (90.2%), and detection (90.0%) rates were also remarkable in third-trimester pregnancies. We perceive significant advantages from this test regarding medical management and patient satisfaction. CONCLUSIONS: This novel report shows that in Japan prenatal interphase FISH testing is highly informative and accurate, not only in second-trimester pregnancies but also in third-trimester pregnancies. This test provides advantages to both physicians and patients, provided that its capabilities and limitations are understood.

Adult↗
PubMed2001

Generation of periventricular leukomalacia by repeated umbilical cord occlusion in near-term fetal sheep and its possible pathogenetical mechanisms.

Periventricular leukomalacia (PVL) is a major cause of cerebral palsy. However, pathogenetic mechanisms of PVL have not been fully understood. Although it has been postulated that umbilical cord compression is related to the development of PVL, no animal experiments clearly demonstrated an association of umbilical cord occlusion with 'periventricular' white matter lesions. The purpose of this study is to determine whether umbilical cord occlusions could produce periventricular white matter lesions in fetal sheep and to examine how changes in fetal cardiovascular and metabolic variables are related to the induction of brain damage. Fourteen near-term fetal sheep underwent umbilical cord occlusion (3-min total cord occlusions 5 times at 5-min intervals). Dissections performed 24 h after cord occlusion revealed that periventricular white matter lesions were produced in 7 out of 14 sheep fetuses. According to the pattern of brain damage, we classified the fetal sheep into three groups: 5 fetuses with dominant lesions in the periventricular white matter (group I), 4 fetuses with brain lesions in the cerebral cortex and thalamus (group II) and 5 fetuses with no or minimal brain lesions (group III). Group I showed higher blood pressure and higher plasma lipid peroxide levels before cord occlusion compared to the other groups, while group II showed systemic hypotension during cord occlusion. No significant differences in changes in pH, PaCO2, PaO2 and heart rate were found between the three groups. It is speculated that PVL might be produced by an association of preexisting chronic circulatory instability with an acute episode of severe repetitive cord occlusion.

Animals↗
PubMed2001

Pancreatitis-associated protein levels in pancreatic juice from patients with pancreatic diseases.

BACKGROUND: Pancreatitis-associated protein (PAP), the acute-phase protein of the pancreas, is overexpressed in acute pancreatitis. Serum PAP levels were reported to be useful as an indicator of the severity, prognosis and healing of acute pancreatitis. Although PAP was originally identified in pancreatic juice, there has been no clinical report on PAP levels in pancreatic juice. This study was conducted to determine levels of PAP in pancreatic juice (PJ-PAP) in various human pancreatic diseases. METHODS: PAP levels in endoscopically aspirated PJ were measured by enzyme-linked immunosorbent assay in 86 patients with pancreatic diseases. RESULTS: 55% of 22 patients with pancreatic cancer (PC) and 25% of 49 patients with chronic pancreatitis (CP) were positive (> 350 ng/ml) for PJ-PAP. PJ-PAP levels were significantly higher in PC than in CP, in which PJ-PAP was also significantly higher than in 15 control subjects. There was no significant correlation between PJ-PAP and serum PAP, and combination assay of serum PAP and/or PJ-PAP detected 80% of PC cases and 44% of CP cases. CONCLUSIONS: We have demonstrated that human PAP could be detected in pancreatic juice from patients with pancreatic diseases. Determination of PAP in pancreatic juice might be helpful for early detection of pancreatic injury.

Acute-Phase Proteins↗
PubMed2001

PTHrP and PTH/PTHrP receptor expressions in human endometrium.

We investigated menstrual cycle-dependent changes in the expression of PTHrP and PTH/PTHrP receptor in the human endometrium by immunohistochemistry, and competitive reverse transcription and polymerase chain reaction (RT-PCR). Human endometrial tissues were obtained from patients who underwent gynecological surgery due to cervical cancer (carcinoma in situ) or ovarian cancer. The mean age of the 20 patients was 36.5 (range 31-44) years. For analysis of mRNA expression, specimens from proliferative (mid, n=5; late, n=5) and secretory (early, n=4; mid, n=4) phases were used. Immunohistochemical expression of PTHrP and PTH/PTHrP receptor was observed in the cytoplasm of both epithelial and stromal cells. Stronger staining of PTHrP was found in glandular epithelial cells than in stromal cells. The staining during the proliferative phase was stronger than that in the secretory phase and the difference was particularly remarkable when comparing samples from the same patient. PTH/PTHrP receptor was also present in both epithelial and stromal cells of the endometrium. However, no difference was observed in receptor expression between the proliferative and secretory phases. Competitive RT-PCR revealed that the expression of PTHrP mRNA was higher during the proliferative phase than in the secretory phase, although no difference was observed in PTH/PTHrP receptor mRNA expression. The data suggest that endometrial proliferation may be mediated by a local PTHrP autocrine and/or paracrine mechanism.

Adult↗
PubMed2001

Myxedema accompanied by huge portal-systemic shunt without portal hypertension.

A 43-year-old woman with a huge portal-systemic shunt accompanied by myxedema showed slow speech and behavior. Several imaging studies revealed a bold portal-systemic shunt from the splenic vein to the left renal vein. In addition, hypothyroidism caused by chronic thyroiditis was diagnosed, and synthesized thyroxine replacement was effective for the symptoms. However, the serum ammonia and indocyanin green retention remained in the abnormal range, nevertheless the portal vein pressure was normal and findings of liver cirrohsis were not recognized histologically. Surgical shunt closure was performed, resulting in normalized serum ammonia levels and serum branched chain amino acids /aromatic amino acids ratio, and improvement of the ammonia tolerance test.

Adult↗
PubMed2001

Expression of p8 in human pancreatic cancer.

The p8 gene is a recently identified gene with mitogenic activity. p8 expression is induced in acute pancreatitis, pancreatic development, and regeneration. However, the expression of p8 in pancreatic cancer is not reported. We investigated p8 expression in 72 human pancreatic tissues, including 38 pancreatic cancers (PCs), by immunohistochemistry. p8 was overexpressed (positive cells >25% in 1,000 cells) in 71% (27 of 38) of PCs, but in only 17% (3 of 18) of chronic pancreatitis cases. There was no overexpression in mucinous cystadenoma or in normal pancreas. The p8 overexpression rate in PC was significantly higher than that in other conditions (P < 0.05). Reverse transcription-PCR analysis confirmed p8 mRNA overexpression (tumor/nontumor ratio >2) in 75% (3 of 4) of PCs. p8 was overexpressed also in human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). These results suggest that p8 is involved in the development of pancreatic cancer, reflecting its mitogenic activity.

Aged↗
PubMed2000

Nonfunctioning islet cell carcinoma of the pancreas with high serum CEA & CA19-9, K-ras codon 12 mutation, and microsatellite instability.

A 55-year-old man with nonfunctioning islet cell carcinoma showing elevation of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels is described with genetic analyses. Pathological examination of the resected specimen revealed two independent islet cell carcinomas, one in the body and the other in the tail of the pancreas. It was proved immunohistochemically that the tumor cells, particularly those in the tail, were immunoreactive to CEA and CA 19-9 and had the property of duct cells, as well as endocrine cells. Gastrin was demonstrated immunohistochemically in these tumor cells, although its level in serum was not elevated. Genetic analyses of the fresh specimens from the tumor in the body revealed K-ras codon 12 mutation and microsatellite instability. These findings are consistent with its progressive clinical course and strongly suggest that these tumors originate, not from the islet cells of Langerhans, but from protodifferentiated cells, capable of giving rise to all the pancreatic cell types.

Biomarkers↗
PubMed2000

Dimeric inhibin A as a fourth marker for Down's syndrome maternal serum screening in native Japanese women.

OBJECTIVE: This study was conducted to assess the usefulness of dimeric inhibin A as a fourth marker for Down's syndrome screening in addition to AFP, hCG and uE3 markers for native Japanese women. METHODS: Serum specimens from 367 native Japanese women in the second trimester were assayed for dimeric inhibin A levels. Day specific dimeric inhibin A medians were established for gestational ages 15.0-21.9. Weekly median values for the native Japanese were compared with those of a U.S. population. Selected Japanese specimens from 15 diagnosed Down's syndrome and 3 trisomy 18 cases were also assayed for dimeric inhibin A. RESULTS: Dimeric inhibin A levels did not vary greatly over the gestational age range as expected. Median value comparison showed that native Japanese dimeric inhibin A medians are higher than the U.S. population medians by an average of 7.95%. Native Japanese dimeric inhibin A median values in this study are 1.77 times higher in Down's syndrome cases than in unaffected pregnancies. Trisomy 18 dimeric inhibin A levels show no significant difference from the unaffected pregnancies. CONCLUSIONS: This report shows for the first time that dimeric inhibin A can be informative as a fourth marker for Down's syndrome screening in native Japanese women. We expect the addition of dimeric inhibin A to a triple marker protocol will increase the accuracy of predicted risk for all pregnancies screened and increase the detection rate of Down's syndrome affected pregnancies.

Biomarkers↗
PubMed2000

Triple marker screening for trisomy 21, trisomy 18 and open neural tube defects in singleton pregnancies of native Japanese pregnant women.

OBJECTIVE: To report the results of prenatal triple marker screening on a population of Japanese pregnant women. METHODS: From April 1994 through March 1999, a total of 32,925 native Japanese women with singleton pregnancies requested a triple marker-screening test. Multiples of the median values for 3 markers and individual risks for each patient were calculated following adjustment for the Japanese weight correction factor. The risk cut-off values used for Down syndrome (T21), open spina bifida (OSB) and trisomy 18 (T18) were 1: 295, 1: 290, and 1: 100, respectively. Follow-up information was collected postpartum and statistically analyzed. RESULTS: Detection rates (DR) of T21 for women less than 35 years, over 35 years and overall were 58, 94, and 83%, respectively. DR of T18 for women less than 35 years, over 35 years and overall were 75, 79, and 79%, respectively. DR of open neural tube defects (ONTD) was 100%. CONCLUSIONS: The first cumulative data of an intervention program and prospective follow-up studies in Japan have proven to be similar to other published reports. Individual risk values were calculated for each pregnancy for T21, T18 and ONTD. This screening program is more effective than age-dependent screening for detecting T21, T18 and ONTD pregnancies.

Adult↗
PubMed2000

Does the depth of gastric ulceration influence a modified dual therapy with amoxicillin and lansoprazole for Helicobacter pylori-associated gastric ulcer?

PURPOSE: To clarify whether the depth of ulceration evaluated by endoscopic ultrasonography (EUS) influences a modified dual therapy with amoxicillin and lansoprazole for the treatment of Helicobacter pylori-positive patients with gastric ulcer. PATIENTS AND METHODS: Twenty-two consecutive cases of gastric ulcer (nine superficial ulcers and 13 deep ulcers) in H pylori-positive patients were studied. Ten of 22 patients received a two-week eradication therapy with amoxicillin 1500 mg/day, lansoprazole 30 mg/day and a new antiulcer agent with features in common with sucralfate, ecabet sodium, 2.0 g/day. They continued to receive the same doses of lansoprazole and ecabet sodium for the next six weeks. The other 12 patients received the same therapy except for those who underwent the four-week amoxicillin treatment. All patients underwent EUS both at the start of the study and eight weeks later. They then received ecabet sodium alone for the next six months as a maintenance therapy, followed by a six-month interval with no treatment. The final endoscopy was done one year after H pylori eradication therapy was completed to evaluate H pylori status and ulcer recurrence. RESULTS: The rates of endoscopic healing and H pylori eradication in the nine patients with superficial ulcer were 100%, irrespective of the period of amoxicillin treatment. In contrast, the rates of endoscopic evidence of healing and H pylori eradication in the 13 patients with deep ulcer were different for each period of amoxicillin treatment; that is, the rates of reduction in ulcer determined by echo and H pylori eradication in the four patients treated with the two-week amoxicillin course were significantly lower (P=0.03) than those in the nine patients treated with the four-week course. CONCLUSION: Ulcer depth is likely to influence the success of amoxicillin treatment for H pylori-positive patients with gastric ulcer.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

K-ras mutations in duodenal aspirate without secretin stimulation for screening of pancreatic and biliary tract carcinoma.

BACKGROUND: K-ras mutations at codon 12 (KRM) have been detected in over 80% of tissues and pure pancreatic juice (PPJ) samples from patients with pancreatic carcinoma (PCa) and are promising genetic tumor markers. Aspirating PPJ not only requires technical skill, but is also exhausting for patients. The authors attempted to evaluate whether the detection of KRM in the duodenal aspirate (DA) obtained immediately after endoscopic retrograde cholangiopancreatography (ERCP), an easier sample-collecting method than collecting PPJ, could be useful for the diagnosis of PCa and biliary tract carcinoma (BTCa). METHODS: DA was collected endoscopically without secretin stimulation immediately after the ERCP procedure from 160 patients: 38 patients with PCa, 38 with chronic pancreatitis (CP), 22 with BTCa, 20 with adenomyomatosis of the gallbladder (AGB), 22 with cholecystolithiasis (CCL), and 20 control subjects. Mutant allele specific amplification (MASA), which is a highly sensitive method for detecting KRM, was performed, with the DNAs extracted from these samples by phenol-chloroform. RESULTS: The incidence of KRM in DA by MASA was 25 (66%) of the 38 PCa cases, 12 (32%) of the 38 CP cases, and 12 (55%) of the 22 BTCa cases. There was no patient with positive KRM in DA among the 20 cases of AGB, 22 of CCL, and 20 control subjects. The sensitivity was 62% and the specificity 88% in this study design. The KRM incidence was found to be relatively high for the patients with PCa and BTCa by MASA, which is a highly sensitive method, although the incidence of KRM in DA from the patients with PCa was not as high as the incidence in their PPJ with secretin stimulation. CONCLUSIONS: MASA showed a relatively high incidence of KRM even in the DA, which was easily obtained from the patients with PCa and BTCa without secretin stimulation immediately after ERCP. These results suggest that the detection of KRM in the DA by MASA is useful for the screening of both PCa and BTCa.

Adult↗
PubMed1999

Visualization of the endometrium by intrauterine sonography.

Thirty-five women with normal menstrual cycles underwent transvaginal and high-frequency (15- or 20-MHz) intrauterine sonographic examinations for the assessment of the endometrium. Five sonographic patterns of endometrium were recognized by both sonographic techniques, but the pattern visualized differed between techniques in 9 women (26%). The higher resolution of intrauterine sonography provided more detail of the endometrium. Our preliminary experience indicates that high-frequency intrauterine sonography enables more detailed visualization of changes in the endometrium during the menstrual cycle than does transvaginal sonography.

Adult↗
PubMed1999

Amniotic fluid alpha-fetoprotein testing in native Japanese women.

Owing to differences in maternal serum alpha-fetoprotein, human chorionic gonadotrophin and oestriol levels between native Japanese and Caucasian women screened in this laboratory, a study was conducted to measure amniotic fluid alpha-fetoprotein (AFAFP) levels in native Japanese pregnancies. When the native Japanese AFAFP levels were compared with a United States (non-Black) population, the Japanese medians did not decrease as rapidly over the 14 to 22 weeks of gestation period investigated. At 14 weeks, the difference was negligible, graduating to a difference of 20 per cent by 22 weeks' gestation. Native Japanese pregnancy AFAFP levels should be interpreted based upon population data from that group alone. From these findings, prenatal screening laboratories should be encouraged to collect preliminary data for comparison before screening is initiated for a defined ethnic group.

Amniocentesis↗
PubMed1999

Mucin-producing biliary papillomatosis associated with gastrobiliary fistula.

We report a case of mucin-producing biliary papillomatosis in a 78-year-old woman. Abdominal ultrasound (US) and computed tomography (CT) showed wall thickening and dilatation of the intrahepatic bile duct (IHBD), as well as a nodular lesion, 1.2 cm in diameter, in the left branch of the IHBD. Gastric endoscopy revealed excretion of bile-containing mucin on the anterior wall of the body of the stomach. Endoscopic ultrasonography (EUS) showed gastrobiliary fistula and discharge of mucin into the stomach. Needle biopsy of the biliary tumor revealed papillary proliferation, but no malignant cells were recognized histologically. Therefore this patient was diagnosed as having mucin-producing biliary papillomatosis forming gastrobiliary fistula. She did not present with obstructive jaundice, probably because of the fistula. She is alive, without obstructive jaundice, 16 months after the diagnosis without having had surgery. This is, to our knowledge, the first reported case of biliary papillomatosis forming gastrobiliary fistula and with the patient free of obstructive jaundice.

Aged↗