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Biomedical subjects

Y Noda

Publications and source records attributed to Y Noda.

At least 325 records · Page 18Linked to original sources
PubMed1993

[Clinical study of gallbladder cancer associated with acute cholecystitis].

The clinical features of gallbladder carcinoma associated with acute cholecystitis and problems in diagnosing this condition by ultrasonography were investigated. Nine cases of gallbladder cancer with acute cholecystitis and 51 cases of gallbladder cancer without acute cholecystitis were reviewed. There were no obvious differences between those two groups as far as depth of invasion, location of cancer, and the prevalence of gallstones were concerned. However, there was a tendency for detection of cancer associated with acute cholecystitis by ultrasound to be more difficult than detection of cancer without acute cholecystitis. Macroscopic examination of resected specimens showed that superficial or flat type cancers tended to occur more often in cases of acute cholecystitis. This is considered to be the main cause of the difficulty in diagnosing such cancer by ultrasound.

Acute Disease↗
PubMed1993

[Anesthetic management of a patient with pemphigoid for prosthetic replacement after femoral neck fracture].

We report an 83 year-old male with pemphigoid who underwent replacement of a femoral neck prosthesis following femoral neck fracture. Problems associated with anesthetic management of patients with vesiculobullous diseases such as pemphigoid include fluid, electrolyte and protein loss, and secondary infection because of the fragility of the skin and mucous membranes. Avoidance of trauma to the skin and mucous membranes is therefore important. Intubation of the trachea may be hazardous because of the possibility of airway obstruction resulting from oropharyngeal and laryngeal bullae. The patient was successfully anesthetized with spinal anesthesia using 2.5 ml of tetracaine in a 0.4% solution of 0.45% NaCl. An evacutable mattress was used to protect the patient from pressure points in the lateral position, and to minimize the hazards from pressure by spreading the weight. Surgery proceeded uneventfully and the postoperative period was uncomplicated.

Aged↗
PubMed1993

[Availability of determination of serum anti-Helicobacter pylori IgG antibody in diagnosis of Helicobacter pylori infection].

We studied on clinical availability of determination of serum anti-Helicobacter pylori (HP) IgG antibody in diagnosis of HP infection compared with bacterial culture. The population of this study consisted of patients who underwent endoscopic examination in our hospital. Detection and quantification of HP were made by the culture of biopsy specimens taken from the antrum and the body of the stomach. And, simultaneously, serum anti-HP antibody (HP-Ab) was measured by ELISA. The levels of HP-Ab in culture positive patients, 40.6 +/- 33.7U, are significantly higher than that of culture negative patients, 10.6 +/- 9.1U. Sensitivity and specificity in diagnosis of HP infection using determination of serum HP-Ab were 96.2% and 60.0% respectively. Significant correlation was found between the levels of serum HP-Ab and the amounts of HP bacilli in the biopsy specimen taken from body of the stomach.

Aged↗
PubMed1993

[The evaluation of portal venous invasion of pancreatic cancer by endoscopic ultrasonography].

Thirty-six cases of pancreatic cancer including 27 cases of so-called mucin producing cancer of the pancreas, examined with endoscopic ultrasonography (EUS) and treated with surgery, were reviewed to evaluate the usefulness of EUS in the diagnosis of portal venous (PV) invasion. The detection rate of pancreatic tumors cancer by EUS was 92% in 36 cases. The detection rate of PV invasion by EUS was compared with histological results in each case. Judgement of the correlation between the tumor and the PV wall was possible in 30 cases (83%), and the overall accuracy of EUS in the diagnosis of PV invasion was 73%. It is concluded that EUS is a very useful method for diagnosis of PV invasion in cases of pancreatic cancer.

Adenocarcinoma↗
PubMed1992

Carcinoids and endocrine cell micronests of the minor and major duodenal papillae. Their incidence and characteristics.

BACKGROUND: There have been no reports about the incidence and characteristics of carcinoids and endocrine cell micronests (ECM) of the minor and major duodenal papillae. METHODS AND RESULTS: The minor and major duodenal papillae of 78 consecutive autopsy and 117 surgical specimens were examined histologically using mirror-image paraffin-embedded tissue samples. ECM were found frequently in these areas in hematoxylin and eosin-stained sections, and their aggregation patterns were classified into four types: nodular type (Type 1, 2 of 167 in the minor papilla and 1 of 145 in the major papilla), scattered type (Type 2, 39 of 167 and 6 of 145), orifice type (Type 3, 7 of 167 and 0 of 145), and islet-like type (Type 4, 14 of 145 and 0 of 145, respectively). Criteria of neoplastic or nonneoplastic ECM were defined tentatively by histologic and immunohistochemical analyses of the ECM. Type 4 was regarded to be atrophic or regenerating islets of Langerhans. Distinct carcinoids (Type 1), neoplastic ECM (39% of all Type 2 and 3), and nonneoplastic ECM (61% of all Type 2 and 3) were found in 1.2%, 9.0%, and 16.2% of 167 samples of the minor papilla and 0.7%, 1.4%, and 2.8% of 145 specimens of the major papilla, respectively. The endocrine cells composing the carcinoids and the ECM usually were immunoreactive for somatostatin and/or pancreatic polypeptide (PP). They were negative for S-100 beta. CONCLUSION: In duodenal papillae, especially in the minor duodenal papilla, carcinoids and ECM seem to occur more frequently than generally thought, and predominantly consist of somatostatin and/or PP containing cells.

Adolescent↗
PubMed1992

Histologic follow-up of ampullary adenomas in patients with familial adenomatosis coli.

BACKGROUND: The major duodenal papilla is a common site of extracolonic adenoma in patients with familial adenomatosis coli (FAC). However, there have been no reports which have systematically discussed histologic change in atypia of ampullary adenomas with time by their location in the papilla. METHODS AND RESULTS: The major duodenal papillae of 23 patients with FAC were followed endoscopically and histologically for an average of 7.7 years (range, 1 year to 14 years 7 months). Tubular adenomas were detected histologically in 17 of the 23 patients at the first (14) or following examinations (3). They occurred in the orifice and/or ampulla in 11 patients and in the surface of the papilla in 8 patients. Three of the 11 orifice and/or ampulla adenomas contained moderate to severe atypia. There was no histologic change in atypia or malignant transformation during the follow-up period. CONCLUSIONS: In the patients with FAC, the major duodenal papilla had adenoma, i.e., precancerous lesion, at a high incidence (74%), and it is reported that the ampulla of the papilla tended to have extracolonic carcinoma. Therefore, it is necessary to follow duodenal papillae of patients with FAC carefully and take biopsy specimens repeatedly from various sites, especially from the orifice or ampulla even if the papilla seems to be normal.

Adenoma↗
PubMed1992

Effects of oxygen toxicity on early development of mouse embryos.

To examine the effects of oxygen toxicity on embryonic development, mouse pronuclear embryos were cultured under low oxygen conditions with or without superoxide dismutase (SOD), and the blastulation rate was compared with that of embryos cultured under standard conditions. The blastulation rate of mouse pronuclear embryos cultured under standard conditions was only 1.5% (2/131). This rate was increased significantly, to 28.5% (43/151), when the embryos were cultured under low oxygen conditions; and to 31.0% (35/113) when SOD (500 micrograms/ml) was added to the medium under standard conditions; the rate was increased to 75.2% (115/153) when the embryos were cultured under low oxygen conditions in the presence of SOD. The minimum effective concentration of SOD in the culture medium was 50 micrograms/ml under conditions of 5% O2. The blastulation rate was significantly decreased after 1-hr exposure of pronuclear embryos to room atmospheric oxygen concentration (20% O2), and subsequent culture under 5% O2 with SOD did not result in an improved blastulation rate. Culture with SOD under 5% O2 promoted the development of two-cell stage embryos to the blastocyst stage. When two-cell stage embryos were collected 48 hr after hCG and cultured for 66 hr, their blastulation rate was similar to that of embryos collected from mice 114 hr after hCG. These results suggested that embryonic development in vitro is greatly affected by atmospheric oxygen throughout the early embryonic stages and that this harmful effect can be prevented by culturing embryos under low oxygen conditions and in the presence of SOD.

Animals↗
PubMed1992

Atrial natriuretic peptide (ANP): a study of ANP and its mRNA in cardiocytes, and of plasma ANP levels in non-obese diabetic mice.

Atrial natriuretic peptide (ANP) levels in cardiocytes and plasma were examined by using immunohistochemistry, electron microscopy, and radioimmunoassay in non-obese diabetic mice (NOD). Cardiocyte ANP mRNA expression was measured by the polymerase chain reaction method. ANP immunoreactivity in the auricular cardiocytes was more prominent in hyperglycemic mice (NOD-h) than in normoglycemic mice (NOD-n). Ultrastructural examination showed that auricular cardiocytes of the NOD-h group contained more cytoplasmic granules than cells of the NOD-n group. Ultrastructural morphometry indicated that the number of granules per auricular cardiocyte was significantly larger in the NOD-h group than in the NOD-n group (P less than 0.01), whereas the granule diameter was significantly smaller in the NOD-h group (P less than 0.01). Radioimmunoassay showed that ANP levels in the NOD-h auricular cardiocytes were significantly higher than those in the NOD-n cardiocytes (P less than 0.01); the opposite was true in plasma. Cardiocyte ANP mRNA expression was lower in the NOD-h group than in the NOD-n group.

Animals↗
PubMed1992

Effects of superoxide dismutase on mouse in vitro fertilization and embryo culture system.

PURPOSE: We recently found that, for mouse embryos fertilized in vivo, the two-cell block could be attenuated by adding superoxide dismutase (SOD), a scavenger of superoxide radicals, to the culture medium. In this study, we evaluated the effects of SOD on the process of fertilization and on the further development of the embryos fertilized in vitro. METHODS: We performed incubation of mouse epididymal spermatozoa, in vitro fertilization, and further cultivation in Biggers-Whitten-Whittingham's medium supplemented with various concentrations of Cu.Zn-SOD. RESULTS: High concentrations (2000 micrograms/ml or more) of SOD prevented loss of motility in mouse sperm over time. The addition of SOD (less than 2000 micrograms/ml) to the basic medium showed no significant difference in the fertilization rate. Also, no significant difference was observed in the rate of polyspermy or parthenogenesis between the basic and the SOD-supplemented media. However, 18% of the two-cell-stage embryos developed to the expanded blastocyst stage in the 500 micrograms/ml SOD-supplemented medium, while no blastocysts were found in the basic medium. Furthermore, the addition of SOD 7 hr after insemination increased the expanded blastocyst rate (28%). CONCLUSIONS: These results indicate that the addition of SOD exerts a protecting effect from oxidative stress both on sperm viability and on the development of embryos fertilized in vitro as well as in vivo, while its addition showed no effect on the process of fertilization.

Animals↗
PubMed1992

Effect of visual light on in vitro embryonic development in the hamster.

The effect of light exposure during collection and culture of hamster embryos on their subsequent development in vitro was examined. When embryos were collected under dark conditions (70 lux) within 10 minutes and then cultured in a HECM-1 medium in 5% CO2 in air, the developmental rates of 1-cell embryos to the 4- and 8-cell stages were 88.6% (93/105) and 66.7% (70/105), respectively. These rates were significantly higher than those under light conditions (1600 lux): 51.9% (56/108) and 34.3% (37/108). Light irradiation during the culture of 1-cell embryos suppressed subsequent development. The degree of suppression correlated inversely with duration of light irradiation, and light irradiation of 30 minutes or more completely blocked development to the 2-cell stage. When 1-cell embryos were irradiated through a yellow filter, cutting the light wavelengths to less than 500 nm, embryonic development was still suppressed. However, the degree of the suppression varied and 45.7% (53/116), 6.0% (7/116), and 0.9% (1/116) of the embryos developed to the 2-, 4-, and 8-cell stages, respectively, under 30 minute light irradiation. Inhibitory effects of light irradiation on the development of 2- and 8-cell embryos were also observed, showing an inverse correlation with duration; the developmental rates of 2-cell embryos to the 8-cell stage under 0, 10, and 30 minutes of irradiation were 85.6% (107/125), 1.6% (2/122), and 0% (0/129), respectively, and those of 8-cell embryos to the blastocyst stage were 79.8% (91/114), 74.8% (86/115), and 0% (0/110), respectively. These findings indicate that early-stage embryos are sensitive to light exposure; however, severe light exposure adversely affects the development of embryos at any stage. Thus, the protection of embryos from light exposure at all stages of embryo manipulation, from collection to culture, is essential.

Journal Article↗
PubMed1992

Oxidative stress on mouse embryo development in vitro.

Oxygen radicals are involved in the in vitro block phenomenon of embryo development, because a low oxygen tension and superoxide dismutase (SOD) have been shown to promote the in vitro development of mouse embryos. One of the target molecules damaged by oxygen radicals may be the thiol (SH) group of proteins because it is readily oxidized. In this study, we evaluated the effects of thioredoxin, which is a powerful protein disulfide reductase, on mouse (Institute of Cancer Research, ICR) preimplantation embryo development. Culture of mouse pronuclear embryos recovered 17 h after human chorionic gonadotrophin (hCG) administration in the presence of thioredoxin (200 micrograms/mL) significantly increased the blastulation rate (75.3%) when compared to the control culture system (8.9%). The effects of thioredoxin were observed only from the pronuclear stage to the two-cell stage (17-48 h after hCG administration). An additive effect of thioredoxin and SOD, or thioredoxin and a low oxygen tension, was observed. These results suggest that the oxidation of the SH group of proteins is one of the causes of developmental blockage of embryos in vitro. The target protein for reduction by thioredoxin has not been identified yet, but thioredoxin will be a new clue for clarifying the mechanism of blocking development in vitro.

Amino Acid Sequence↗
PubMed1992

Interaction of dynamin with microtubules: its structure and GTPase activity investigated by using highly purified dynamin.

We purified a large amount of dynamin with high enzymatical activity from rat brain tissue by a new procedure. Dynamin 0.48 mg was obtained from 20 g of rat brain. The purity of dynamin was almost 98%. Dynamin plays a role of GTPase rather than ATPase. In the absence of microtubules, Michaelis constant (Km) and maximum velocity (Vmax) for dynamin GTPase were 370 microM and 0.25 min-1, respectively, and in their presence, both were significantly accelerated up to 25 microM and 5.5 min-1. On the other hand, the ATPase activity was very low in the absence of microtubules, and even in their presence, Km and Vmax for dynamin ATPase were 0.2 mM and 0.91 min-1. Despite slow GTPase turnover rate in the absence of microtubules, binding of GTP and its nonhydrolizing analogues was very fast, indicating that GTP binding step is not rate limiting. Dynamin did not cause a one-directional consistent microtubule sliding movement just like kinesin or dynein in the presence of 2 mM ATP or 2 mM GTP. We observed the molecular structure of dynamin with low-angle rotary shadowing technique and revealed that the dynamin molecule is globular in shape. Gel filtration assay revealed that these globules were the oligomers of 100-kDa dynamin polypeptide. Dynamin bound to microtubules with a 1:1 approximately 1.2 molar ratio in the absence of GTP. Quick-freeze deep-etch electron microscopy of the dynamin-microtubule complex showed that dynamin decorates the surface of microtubules helically, like a screw bolt, very orderly and tightly with 11.4 +/- 0.9 (SD)nm period. Contrary to the previous report, microtubules make bundles by the attachment of the dynamin helixes around each adjacent microtubule, and no cross-bridge formation was observed.

Amino Acid Sequence↗
PubMed1992

Localization of CuZn-superoxide dismutase in the human male genital organs.

We performed an immunohistochemical analysis using a polyclonal antibody to determine the localization of CuZn-superoxide dismutase (SOD), a scavenger of superoxide anion radicals, in the human male genital organs. In the testis, intense immunoreactivity of CuZn-SOD was shown in both the cytoplasm and nucleus of the spermatogonia of the seminiferous tubules. Spermatocytes, further differentiated germ cells and Sertoli cells showed no or weak immunoreactivity. In the ductus epididymis, the principal cells showed no or weak immunoreactivity except for the stereocilial region, while the basal cells showed relatively intense immunoreactivity. In the ductus deferens, the prostate and the seminal vesicles, columnar and cuboidal epithelia showed CuZn-SOD immunoreactivity. The immunoreactivity was more intense in the epithelia of the ductus deferens than in the prostate or the seminal vesicles. Basal cells in the prostate also showed intense immunoreactivity. Collectively, the present immunohistochemical results suggest that CuZn-SOD in the male genital organs is localized where it could play an important role in cell differentiation, including spermatogenesis. The CuZn-SOD could also play a role in local defence mechanisms against tissue damage mediated through superoxide anion radicals, as well as in providing SOD to the seminal plasma.

Adult↗
PubMed1992

Pregnancy achieved by transferring blastocysts into endometrial stroma in mice.

To prevent the extra-uterine discharge of transferred embryos, we directly inserted mouse embryos into the endometrial stroma (intra-endometrial embryo transfer). A 27G injection needle was inserted near the utero-tubal junction into the endometrial stroma. After removal of the needle, a glass micropipette was inserted and one embryo was transferred with a very small amount of culture medium. To determine the feasibility of this method, the uterine lumen was flushed with phosphate-buffered saline from the tubal ends immediately after transferring blastocysts into pseudopregnant mice on day 2 and day 4. The rates of recovery of embryos from the uterine lumen were 5.0% (1/20; day 4) and 15.0% (3/20; day 2). These results suggest that a high rate of intra-endometrial embryo transfer is possible. The embryonic viability rates (number of viable grown fetuses/number of blastocysts transferred) of this method were 50.0% (28/56; day 4) and 25.0% (5/20; day 2). Living offspring were delivered from both recipients which had received embryos on day 2 and day 4 of pseudopregnancy. In human in-vitro fertilization and embryo transfer, attempts have also been made to immobilize the embryos, and this method might be clinically applicable. Moreover, this method will be a good in-vivo model for studies on the mechanism of implantation.

Abortion, Veterinary↗