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Biomedical subjects

S Aoki

Publications and source records attributed to S Aoki.

At least 181 records · Page 10Linked to original sources
PubMed1998

Three-dimensional intrauterine sonography in the early first-trimester of human pregnancy: preliminary study.

Our purpose was to visualize normal embryonal surface anatomic structures using three-dimensional (3D) intrauterine sonography with a 20 MHz flexible catheter-based high-resolution real-time miniature transducer in the early first trimester of pregnancy. A total of 15 women about to undergo therapeutic abortion at 7-9.9 weeks gestational age were studied by means of 3D intrauterine sonography with a specially developed catheter-based high-resolution real-time miniature (2.4 mm in outer diameter) ultrasound transducer (20 MHz). This imaging system can provide conventional 2D intrauterine sonographic images and can also generate within seconds high-quality 3D images in the surface and transparent mode. At week 8, prominent forehead was evident, and upper and lower limbs and midgut herniation were clearly depicted. At week 9, fingers and toes were depicted as small digital rays, and the sacral tail protruded caudally. The midline cranial ectodermal cleft was also identified. At week 10, embryonic face and fingers were clearly shown. 3D intrauterine sonography provides a novel means for visualizing of surface anatomic structures of the human embryo in utero. These results suggest that 3D intrauterine sonography can become an important modality in future embryological research and in detection of embryonic developmental disorders in the early first-trimester pregnancy.

Embryo, Mammalian↗
PubMed1998

Maternal and fetal nitric oxide synthesis is decreased in pregnancies with small for gestational age infants.

Our purpose was to evaluate whether maternal and fetal nitric oxide synthesis in pregnancies with small for gestational age (SGA) infants are different from those in pregnancies with appropriate for gestational age (AGA) infants. Maternal and fetal circulating nitrate and nitrite concentrations were compared between 30 pregnancies with AGA and 10 pregnancies with SGA at birth. End-products of nitric oxide synthesis were measured in maternal and cord venous blood samples using a fluorometric assay. Umbilical artery blood pH and PO2 were also measured. Maternal circulating nitrite and nitrate concentrations (6.91 +/- 1.27 microM) in pregnancies with SGA were significantly lower than those (11.69 +/- 1.33 microM) in pregnancies with AGA (P = 0.015). Fetal circulating nitrite and nitrate concentrations (7.54 +/- 1.09 microM) in pregnancies with SGA were also significantly lower than those (11.24 +/- 1.08 microM) in pregnancies with AGA (P = 0.024). There were no significant differences in umbilical artery blood pH and PO2 between the two groups. These results suggest that maternal and fetal nitric oxide synthesis are decreased in pregnancies with SGA infants.

Adult↗
PubMed1998

Comparison of early- and late-onset rapid cycling affective disorders: clinical course and response to pharmacotherapy.

This study compared the clinical course and response to pharmacotherapy of patients with rapid cycling affective disorder (RCAD). A retrospective study was conducted on outpatients with affective disorder from 1991 to 1992 at Okayama University Medical School to select cases of RCAD. The subjects were 35 patients who fulfilled DSM-III-R criteria for mood disorder and had experienced at least four episodes of illness during the previous year. The subjects were divided into two groups according to their age at the first phase of affective illness: an early-onset group, consisting of patients aged 25 years or younger, and a late-onset group, consisting of patients aged 26 or older. There were 14 patients in the early-onset group and 21 in the late-onset group. Both the mean duration from onset to rapid cycling and the mean duration of each phase were shorter in the early-onset group than in the late-onset group. There were no significant differences between the groups in period of remission, character of the first episode, heredity, or thyroid function. Lithium carbonate therapy was more effective for reducing manic symptoms in the late-onset group than in the early-onset group, without maintaining a prophylactic effect in either group, whereas carbamazepine was more effective in the early-onset group. Antidepressants used in the depressive phase had a tendency to be more effective in the late-onset than in the early-onset group. However, rapid cycling induced by antidepressants was more evident in the late-onset than in the early-onset group. These findings supported the differentiation of RCAD into two groups based on age at onset, the early-onset group showing a rapid cycling course at an early stage and a good response to carbamazepine, the late-onset group having a relatively long disease duration until the appearance of a rapid cycling course and a good response to lithium carbonate in the manic phase and to antidepressants in the depressive phase.

Adolescent↗
PubMed1998

Familial occurrence of congenital bile duct cysts.

Congenital bile duct cysts are now a well-documented anomaly of the biliary tree, and have become more common in Japan. Familial occurrence of congenital bile duct cysts, however, is extremely rare, with only six reported cases in the literature. We report a familial pattern of congenital bile duct cysts in a mother and her daughter. A 33-year-old female was admitted for evaluation of right upper quadrant abdominal pain and fever 6 days after an uneventful delivery of her second child. A computed tomography (CT) and ultrasound scan (US) revealed an obstructed biliary tract. Percutaneous transhepatic biliary drainage was then performed, and a cholangiogram revealed a Scholtz type B choledochocele without an anomalous connection of the pancreaticobiliary ducts. Endoscopic US demonstrated that the choledochocele was associated with a stone in the cyst. A pylorus-preserving pancreatoduodenal resection was performed, and a histological study revealed that the choledochocele was lined by biliary mucosa without evidence of malignancy. The newborn infant had an abdominal tumour. An US and CT revealed a congenital bile duct cyst. An operation was performed and the intraoperative cholangiogram showed an Alonso-Lej type I congenital bile duct cyst with an anomalous connection of the pancreaticobiliary ducts. Whether congenital bile duct cysts are hereditary remains to be elucidated.

Adult↗
PubMed1998

Clonazepam as a therapeutic adjunct to improve the management of psychiatric disorders.

Clonazepam, which is a benzodiazepine structurally related to chlordiazepoxide hydrochloride, diazepam and nitrazepam, has been available for the treatment of seizure disorders in the USA since 1976 and in Japan since 1981. Increasingly, clonazepam has been used in the treatment of a variety of psychiatric disorders. Six representative case studies are presented and specific guidelines for the use of clonazepam are discussed.

Adult↗
PubMed1998

Differences of IgG and IgM antibodies to phospholipids and APTT among non-pregnant and pregnant women.

OBJECTIVE: The objective of our study was to assess the difference in IgG and IgM antibodies to cardiolipin(CL), phosphatidylserine(PS), and APTT among non-pregnant and pregnant women. METHODS: IgG and IgM antibodies to CL and PS among 102 healthy non-pregnant women and 154 healthy pregnant women were measured by an ELISA. The activated partial thromboplastin time(APTT) was measured in 67 healthy non-pregnant women, in 67 healthy women at 10-14 weeks of gestation, and in 67 healthy women at 30-32 weeks of gestation. We compared the titer of +2SD in each group. RESULTS: The titers +2SD of IgG antibodies to CL and PS in pregnant women were lower than in non-pregnant women (p < 0.05), whereas the values of the IgM antibody to CL and PS were the same in pregnant and non-pregnant women. The APTT in pregnant women was significantly shorter than in non-pregnant women (p = 0.0001). CONCLUSION: Standard criteria for the positivity of the IgG antibody to CL and PS and the prolongation of APTT in pregnancy should employ the values of normal pregnant women rather than those of non-pregnant women.

Adult↗
PubMed1998

Power Doppler enhancement of the placenta by dehydroepiandrosterone sulphate in term pregnancy.

We studied the effect of dehydroepiandrosterone sulphate (DHAS) on placental blood flow in 11 women with an uncomplicated pregnancy between 37 and 39 weeks of gestation. Power Doppler enhancement of the placenta was performed before and 60 minutes after the administration of a 200 mg intravenous dose of DHAS dissolved in 20 mL of 5% dextrose. Increased power Doppler enhancements of the placenta after DHAS injection were evident in each case studied. The power Doppler enhancement returned to the baseline imaging within 60 minutes. This DHAS loading test, assessed by means of power Doppler imaging, may be a useful technique when attempting to assess fetoplacental function in normal and high risk pregnancies.

Acetone↗
PubMed1998

A period-extender gene, pex, that extends the period of the circadian clock in the cyanobacterium Synechococcus sp. strain PCC 7942.

We cloned the pS1K1 plasmid in the process of apparently "complementing" a circadian clock mutant of cyanobacterium Synechococcus sp. strain PCC 7942, SP22, which has a 22-h period (T. Kondo, N. F. Tsinoremas, S. S. Golden, C. H. Johnson, S. Kutsuna, and M. Ishiura, Science 266:1233-1236, 1994). Sequence analysis revealed that SP22 did not have a mutation in the genomic DNA segment carried on pS1K1, and the sp22 mutation was later found in a recently cloned new clock gene, kaiC. Therefore, the period-extender gene pex that was carried on pS1K1 was a suppressor gene for the sp22 mutation. The pex gene encoded a protein of 148 amino acid residues. No meaningful homologs were found in DNA or protein databases including the Synechocystis genome database. The pex gene was transcribed from 129 and 164 bp upstream of the translation initiation codon as 0.6-kb transcripts. The Pex protein was detected as a fusion protein with a molecular mass of 15 kDa by the epitope tag fusion method using a c-Myc epitope tag. Disruption of the pex gene in wild-type cells shortened the period of the rhythms by 1 h, although it did not affect other properties of the rhythms, whereas its overexpression extended the period by 3 h with a concomitant reduction in the amplitude of the rhythms. In various clock mutants examined, overexpression caused arrhythmicity. Thus, Pex is likely to function as a modifier of the circadian clock in Synechococcus.

Amino Acid Sequence↗
PubMed1998

Three-dimensional ultrasonographic assessment of the umbilical cord during the 2nd and 3rd trimesters of pregnancy.

OBJECTIVE: To evaluate the umbilical cord and its abnormalities by use of three-dimensional ultrasonography with a specially developed abdominal three-dimensional transducer. PATIENTS AND METHODS: Ninety-five pregnancies (92 normal, 2 with hydrops fetalis, and 1 with omphalocele) from 14 to 40 weeks of gestation were studied with a specially developed abdominal three-dimensional transducer (3.5 MHz). This system can provide conventional two-dimensional ultrasonography images and can also generate within seconds high-quality three-dimensional images in the surface and transparent mode with no need for an external workstation. A proportion of the umbilical cords (coiled or noncoiled free loop, abdominal insertion, and placental insertion) visualized at each gestational age interval is presented. RESULTS: The proportion of the umbilical cords visualized during pregnancy except for between 24 and 27 weeks of gestation was about 70% (range 64-83%). Optimal visualization of the umbilical cord was achieved between 24 and 27 weeks of gestation. During this period it was possible to adequately depict the umbilical cord in 93% of the cases. The proportions of the noncoiled umbilical cord depicted during pregnancy ranged from 8 to 45%. The detection rate of abdominal insertion of the umbilical cord visualized at 14-19 weeks was 44%; the detection rate decreased thereafter. Placental insertion of the umbilical cord could not be identified after 28 weeks of gestation. In 2 cases with hydrops fetalis, edematous umbilical cord was evident. In 1 fetus, omphalocele was clearly depicted. CONCLUSIONS: The new three-dimensional ultrasound technology generates within seconds high-quality three-dimensional images of the umbilical cord, although limitation of viewing direction exists. These results suggest that the new three-dimensional ultrasonography has the potential to be a supplement to two-dimensional ultrasonography and might be useful in identifying abnormal umbilical cords in utero.

Edema↗
PubMed1998

Three-dimensional ultrasonographic visualization of multiple pregnancy.

Our purpose was to describe interrelationships and contacts between twins in utero by use of three-dimensional ultrasonography with a specially developed abdominal three-dimensional transducer. Thirteen twin pregnancies (3 monochorionic and 10 dichorionic pairs) and one triplet pregnancy (trichorionic triplet) from 9 to 36 weeks of gestation were studied with a specially developed abdominal three-dimensional transducer (3.5 MHz). This imaging system can provide conventional two-dimensional ultrasonography images and can also generate within seconds high-quality three-dimensional images in the surface and transparent mode with no need for an external workstation. Interrelationships and contacts between twins or triplets are described. Various types of contacts (head/body/arm/leg) and interrelationships were clearly visualized. Crowding of in utero twin fetuses increased with advancing gestation. Sometimes two placentas and dividing membrane were beautifully depicted. In one triplet pregnancy, the interrelationships among 3 fetuses and dividing membranes were easily recognized. Three-dimensional ultrasonography provides a novel means of visualizing multiple pregnancies in utero. These results suggest that three-dimensional ultrasonography has the potential to be a supplement to two-dimensional ultrasonography and would be useful in evaluating the interhuman contacts and crowdings of twin and triplet fetuses in utero.

Female↗
PubMed1998

Absorption of ibuprofen coated by anhydrous silicic acid.

We studied the dissolution and absorption of ibuprofen (IB) from a three-layer tablet: the 1st layer (CIB layer) consisted of IB which was coated with anhydrous silicic acid (CIB), the 2nd layer was bromovalerylurea and anhydrous caffeine, and the 3rd layer was bromovalerylurea and ethenzamide. Differential scanning calorimetry and powder X-ray diffraction studies showed that the crystallinity of IB was not influenced by the preparation of CIB. The dissolution and absorption of IB from the CIB layer of the three-layer tablet were compared with those of a commercial tablet. In a test solution at pH 1.2, the dissolution rate of IB from the CIB layer was higher than that from the commercial tablet; moreover, the time for peak concentration (Tmax) after administration of the CIB layer was significantly shorter. The Tmax of the CIB layer tablet was about 52 min, while that of the commercial tablet was about 103 min. The rapid dissolution and absorption of IB in the CIB layer may be due to enhanced permeation, disintegration and disaggregation of CIB.

Biological Availability↗
PubMed1998

[Effect of tableting conditions on the sticking of tablet using ibuprofen].

Influence of tableting conditions on sticking was investigated using two formulations, the one formulation containing ibuprofen (formulation A) and the other being the standard formulation (formulation B). Sticking was observed on formulation A, and was not observed on formulation B. The degree of sticking was decreased with increase in compression pressure, and increased with compression speed. The shape of punch face was influenced the degree of sticking (sugar concave < bebel < flat). It was thought that sticking was observed when the adhesion between tablet and punch was larger than that among tableting granules. We investigated the pressure placed on a scraper (SCR), the adhesion between granules and metal, and boring hardness of tablet. The results showed that sticking was not observed when the SCR and/or the adhesion were small enough or boring hardness of tablet was high enough. Furthermore, it was suggested that boring hardness distribution would influence sticking.

Adhesiveness↗
PubMed1998

Histoplasmosis in the skin and gingiva in a dog.

An 8-year-old, female mongrel dog had granulomatous lesions in the skull skin and gingiva of the left mandible. The lesions were macroscopically seen as grayish white papular granulomas, and microscopically consisted to numerous swollen macrophages and a few neutrophils without fibrocaseous necrosis. Macrophages contained many small oval or round-shaped yeast-like cells and a few rod-shaped organisms indicating a narrow based budding in their cytoplasm. The yeast-like cells were 2-5 microns (average 3.5 microns) in diameter, and appeared as a central, spherical, lightly basophilic body surrounded by a clear zone or "halo". The cell wall and central body were stained by the periodic acid-Shiff, Grocott's methenamine silver impregnation, or Gridley fungus method. Immunohistochemically, yeast-like cells were positive to anti-histoplasma yeast antibody, and rod-shaped organisms were positive to anti-histoplasma mycelial antibody. The present paper describes the first case of canine histoplasmosis in Japan.

Animals↗
PubMed1998

Double infection with Giardia lamblia and Salmonella paratyphi A associated with acute renal failure.

While traveling in India, a previously healthy twenty-year-old man had febrile diarrhea. The patient was prescribed medical therapy, and all symptoms were resolved. Fourteen days later, however, similar symptoms recurred. The patient was admitted to a local hospital, but was transferred to our department because of oliguria. Salmonella paratyphi A was isolated from blood and stool specimens, and Giardia lamblia was identified in his stool. The patient's condition was complicated by acute renal failure. The patient received tosufloxacin and metronidazole. Renal function recovered completely without hemodialysis. Paratyphoid fever and giardiasis were resolved. It is suggested that giardiasis exacerbated the paratyphoid fever.

Acute Kidney Injury↗
PubMed1998

Three-dimensional sonographic visualization of the fetal face.

OBJECTIVE: This study was done to show the potential of using three dimensional (3D) sonography to reveal fetal facial anomalies. SUBJECTS AND METHODS: Ninety-four healthy fetuses from 15 to 40 weeks' gestation were studied with a specially developed 3.5-MHz abdominal 3D transducer. This imaging system provided conventional two-dimensional (2D) sonographic images and also generated within seconds high-quality 3D images in the surface and transparent modes with no need for an external workstation. RESULTS: Using this imaging system, we obtained 2D and 3D images of fetal faces (forehead, eyes, nose, lips, and chin) at six gestational ages. At less than 24 weeks' gestation, 65% of facial structures were visualized. The image quality was slightly degraded because of the small fetal size. At or after 24 weeks' gestation, 84% of facial structures were revealed. We found no significant difference in image quality of the fetal face between 2D and 3D sonography. CONCLUSION: The new 3D sonographic technology can generate within seconds high-quality 3D images of the fetal face. The 3D technology seems to perform at least as well as conventional 2D sonography. Our results suggest that 3D sonography has the potential to supplement 2D sonography and might be useful in identifying malformations of the fetal face and chromosomal abnormalities in utero.

Face↗
PubMed1998

[Adenoid cystic carcinoma of the prostate. A case report].

Adenoid cystic carcinoma is most commonly encountered in the salivary glands. It is rarely found in the prostate but distinctive variant of prostatic adenocarcinoma. This case report is thought to be the first one in the Japanese literature. A 51-year-old man was admitted with urinary difficulties and frequency since one month. Digital rectal examination revealed an enlarged stony hard prostate. The transurethral prostatectomy was performed and the histopathological diagnosis was the adenoid cystic carcinoma. PSA and PAP were normal. The findings of computerized tomography suggested the invasion to the bladder and rectum. Therefore the total pelvic excenteration was carried out. He subsequently received radiation therapy (50 Gy to the pelvis), anti-androgen therapy and three courses of chemotherapy using Cisplatin, Peplomycin, Epirubicin and so on. But the metastatic disease involving the liver and pelvic lymph nodes developed, and he died two years seven months postoperatively.

Carcinoma, Adenoid Cystic↗