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Biomedical subjects

S Oyama

Publications and source records attributed to S Oyama.

At least 19 recordsLinked to original sources

A new reconstructive procedure after segmental pancreatectomy: an experimental study of pancreatic end-to-end (duct-to-duct) anastomosis.

We produced experimental models of pancreatic end-to-end anastomosis, including ductal end-to-end anastomosis (with or without stent) and pancreaticojejunostomy, using mongrel dogs, with a view to evaluating reconstructive procedures after segmental pancreatectomy. We examined macroscopic findings, pancreatograms, and microangiographic and histopathological findings to determine whether pancreatic end-to-end anastomosis was as practicable as pancreaticojejunostomy. Macroscopic findings showed no suture failure in any animal in the end-to-end anastomosis group. Pancreatography revealed obstruction of the stent tube in the stent subgroup, but good patency in the no-stent subgroup. On the imaging of the microvasculature in the end-to-end anastomosis group, proliferation of neovascular vessels and formation of communicating vessels were detected. Histopathologically, no suture failure was detected, and the viability of the pancreatic end-to-end anastomosis was confirmed. From this experiment, we concluded it that it was possible to employ pancreatic end-to-end anastomosis after segmental pancreatectomy in the clinical situation.

Anastomosis, Surgical↗

Density and Distribution of Citemene Fields in a Miombo Woodland Environment in Zambia.

/ The Bemba people of northern Zambia practice citemene shifting cultivation. We utilized Landsat satellite images from 1984 and 1992 to map the distribution of citemene fields in those two years and to assess changes in the spatial sustainability of citemene cultivation in a miombo woodland study area. The citemene fields were concentrated within about 5-6 km of roads. Between 1984 and 1992, there was a decrease in the number of fields, and an increase in the average distance from the road. These changes may have been due to the introduction of semipermanent maize farming in the intervening years. The estimated cycle times for woodland utilization may have been long enough to maintain sustainability under traditional citemene cultivation practices. However, cycle times may be too short to maintain sustainability within the woodlands along roads.KEY WORDS: Shifting agriculture; GIS; Sustainability; Citemene; Miombo; Zambiahttp://link.springer-ny.com/link/service/journals/00267/bibs/24n2p273.html

Journal Article↗

[Analysis of air pollution and prevalence rate of allergic diseases among elementary school children in Kawaguchi and Hatogaya city].

Kawaguchi and Hatogaya City are located on the northern edge of Tokyo. We analysed between air pollution and prevalence rate of allergic diseases among elementary school children in this area. A prevalence rate of allergic diseases in 1996 May and June was as follows; bronchial asthma 13.5%, atopic dermatitis 24.5%, allergic rhinitis and/or conjunctivitis 22.8%, urticaria 12.4%, food allergy 7.8% and drug allergy 2.2%, respectively. Air pollution of this area was analysed to check the levels of nitrogen dioxide (NO2), sulfur dioxide (SO2) and suspended particulate matters (SPM). NO2 pollution was relatively high in urban area, and SPM pollution was especially high around the highways. SO2 pollution was lower than the environmental standard. No relationship was found between the prevalence rate of bronchial asthma, atopic dermatitis, allergic rhinitis and/or conjunctivitis and air pollution, but it was found that these diseases are slightly related to population density (p < 0.1, p < 0.01, p < 0.1, respectively).

Air Pollutants↗

Selective inhibition of platelet-derived growth factor (PDGF) receptor autophosphorylation and PDGF-mediated cellular events by a quinoline derivative.

This report describes the biological effects of our original compound, Ki6783 ((3,4-dimethoxy)-4-phenoxy-6,7-dimethoxyquinoline), a potent and selective inhibitor of platelet-derived growth factor (PDGF) receptor autophosphorylation. This compound strongly inhibited autophosphorylation of the PDGF beta-receptor in cultured rat glomerular mesangial cells (MC) bearing this receptor (IC50 0.1 microM), although it did not inhibit autophosphorylation of other growth factor receptors even at 100 microM. In a cell-free kinase experiment, it showed selective inhibition of PDGF beta-receptor tyrosine kinase. A kinetic study of the compound to this tyrosine kinase revealed a competitive mode of action to ATP. [3H]Thymidine incorporation and cell proliferation of MC were inhibited by Ki6783 in a dose-dependent manner after Ki6783 and PDGF-BB were added to the culture medium. Furthermore, this compound normalized the fibrotic cell shape of v-sis-transformed NIH3T3 cells, which grow in an autocrine manner via the PDGF receptor. These effects could be explained by the inhibition of intracellular signal transduction triggered by PDGF receptor autophosphorylation, in which activation of mitogen-activated protein kinase occurs. These results suggest that Ki6783 is one of the more potent and selective inhibitors of PDGF receptor autophosphorylation and that it may be useful in ameliorating cell abnormalities due to excess action of PDGF and its receptor systems in several diseases.

3T3 Cells↗

Construction of a contiguous 874-kb sequence of the Escherichia coli -K12 genome corresponding to 50.0-68.8 min on the linkage map and analysis of its sequence features.

The contiguous 874.423 base pair sequence corresponding to the 50.0-68.8 min region on the genetic map of the Escherichia coli K-12 (W3110) was constructed by the determination of DNA sequences in the 50.0-57.9 min region (360 kb) and two large (100 kb in all) and five short gaps in the 57.9-68.8 min region whose sequences had been registered in the DNA databases. We analyzed its sequence features and found that this region contained at least 894 potential open reading frames (ORFs), of which 346 (38.7%) were previously reported, 158 (17.7%) were homologous to other known genes, 232 (26.0%) were identical or similar to hypothetical genes registered in databases, and the remaining 158 (17.7%) showed no significant similarity to any other genes. A homology search of the ORFs also identified several new gene clusters. Those include two clusters of fimbrial genes, a gene cluster of three genes encoding homologues of the human long chain fatty acid degradation enzyme complex in the mitochondrial membrane, a cluster of at least nine genes involved in the utilization of ethanolamine, a cluster of the secondary set of 11 hyc genes participating in the formate hydrogenlyase reaction and a cluster of five genes coding for the homologues of degradation enzymes for aromatic hydrocarbons in Pseudomonas putida. We also noted a variety of novel genes, including two ORFs, which were homologous to the putative genes encoding xanthine dehydrogenase in the fly and a protein responsible for axonal guidance and outgrowth of the rat, mouse and nematode. An isoleucine tRNA gene, designated ileY, was also newly identified at 60.0 min.

Base Sequence↗

[Efficacy of rectal diazepam suppository in the prophylaxis of febrile seizures: comparison with rectal chloral hydrate suppository].

We evaluated the efficacy of diazepam and chloral hydrate given rectally for the prophylaxis of recurrence of febrile seizure. The dose were 0.4 mg/kg for diazepam and 250 mg (for children younger than 3 years old) or 500 mg (for over 3 years old) for chloral hydrate. Another dose was given after an interval of 8 hours if body temperature continued to exceed 38.0 degrees C. Among the 452 patients with febrile seizures who visited our hospital from Jan. 1993 to Jun. 1995, 113 were studied who had at least one febrile episode in the follow-up period that extended over 6 months. These patients were divided into two groups: Group D (72 patients given diazepam) and Group C (41 patients given chloral hydrate). In group D and C, the numbers of febrile episodes were 238 and 167, and those of recurrent seizures 8 (3.8%) and 29 (20.4%), respectively. The recurrences rate was significantly higher in the latter group (p < 0.005). There was no statistical difference as to the mean dosage of diazepam or chloral hydrate between the patients with and without recurrence. The numbers of patients with seizure recurrence were 8 (11.1%) in group D and 12 (29.3%) in group C, being significantly larger in the latter (p < 0.005). Diazepam produced more adverse effects than chloral hydrate did. Thus diazepam suppositories for the prevention of recurrence of febrile seizures were more effective than chloral hydrate suppositories.

Child↗

Mitogenic activity of peptides related to the sequence of human fibroblast growth factor-1.

Linear synthetic peptides related to the human Fibroblast Growth Factor-1 (hFGF-1) segment [112-147] were tested for their capacity of mimicking FGF mitogenic activity, binding to heparin-Sepharose columns, stimulating DNA synthesis and competing with hFGF-1 for the cellular receptors. The results obtained indicated that the activity of these compounds is dependent on the presence of the sequence WFVGLK in their structures. The affinity for the cellular receptors increased when this sequence was elongated in order to incorporate amino acid residues that are important for FGF-heparin binding.

3T3 Cells↗

Mobile tongue reconstruction with the free dorsalis pedis flap.

Reconstruction of the mobile tongue needs soft and thin tissue not to disturb tongue movement, and therefore a free forearm flap has usually been used for this kind of reconstruction. However, it entails a cosmetic problem, especially for young people. We have detained good results with tongue reconstructions using free dorsalis pedis flaps. The donor site of the dorsalis pedis flap is inconspicuous. The dorsalis pedis flap is thin (even among obese persons), has a long vessel pedicle, and stable blood supply. In cases of head and neck reconstruction, two teams can easily operate simultaneously. This flap is not as large as a forearm flap but it is large enough for hemitongue reconstruction. We measured the thickness of the soft tissue of both the dorsalis pedis and the forearm among obese volunteers. Dorsalis pedis was not as thick as the forearm.

Adult↗

Reconstruction using a free jejunal graft for surgery of the hypopharynx and the cervical esophagus in patients with a history of previous upper gastro-intestinal surgery.

Case 1 had undergone surgery for antrum stenosis 20 years earlier as well as subsequent surgery with reconstruction by Billroth II for carcinoma occurring at the anastmotic site. Case 2 had undergone partial resection of the jejunum for injury of the intestine. Case 3 had undergone reconstruction of the thoracic esophagus using the stomach following excision of carcinoma. For these 3 cases, reconstruction using a free jejunal flap was performed and no disturbance was observed at the donor site. These results strongly suggest that reconstruction using a free jejunal graft be used in patients with a history of previous gastro-intestinal surgeries, with careful observation before and during surgery.

Aged↗

[Progress of the treatment of gastric cancer in Cancer Institute Hospital, Tokyo].

From 1946 to 1990, a total of 10,485 cases of gastric cancer patients were treated at the Cancer Institute Hospital (CIH), Tokyo. During the past 46 years, CIH contributed to various aspects of surgical treatment of gastric cancer; extensive radical surgery for advanced cancer, safe reconstruction methods after total gastrectomy, modified surgery for early stage cancer, and multimodality therapy for moderately advanced cancer. Five-year survival rate was 20% for all cases in 1940s, and 66.5% for 1980s. Improvement in the treatment results could be attributed to the relative increase in the number of early stage cancers, the increase in the rate of curative surgery (R0), and incorporation of multi-modality therapy before or after curative surgery. Stage-oriented therapy is mandatory for further improvement in the treatment results and the patient's quality of life after surgery.

Adult↗

[A case report of 16-year-old gastric cancer patient with a rapid recurrence after curative gastrectomy].

A 16-year-old female patient with gastric cancer was recently treated at our institute. She had macroscopically curative surgery, but relapsed to die 7 months after surgery due to peritoneal dissemination. We experienced three teen-agers over past 45 years, who were 0.019% of all cases treated in our institute. Histological type of these cases was undifferentiated adenocarcinoma, exposing to serosa. Though they had suffered abdominal discomfort for long time, proper diagnosis was not done due to their young age. Even the teen-ager who has abdominal complaints should be subjected to a thorough examination of gastrointestinal tract. Oncogene analysis should be done for the familial strain of gastric cancer.

Adenocarcinoma↗

[Indication for the lymph node dissection of gastric cancer based on the pattern analysis small of lymphatic spread].

A total of 8,230 cases of gastric cancer treated at CIH were subjected to the analysis of the pattern of lymphatic spread with an aim of getting indication for the lymph node dissection of Small gastric cancer. Modified dissection (D1-alpha) is indicated for the patients with following conditions: 1) every elevated or flat type mucosal cancer, 2) excavated (IIc) type mucosal cancer less than 10mm in diameter, 3) elevated or flat type submucosal cancer less than 10mm in diameter, 4) excavated submucosal cancer less than 5mm in diameter. Extended dissection (D2 + alpha) is indicated for small cancer which exposed to serosa. Cancer in the upper thirds needs total gastrectomy or cardiectomy according to the state of #5 and 6 nodes, with complete dissection of #1 to 11 nodes associated with sampling of #16 nodes. Total gastrectomy with complete dissection of #1 to 11 nodes and sampling of #16 nodes is indicated for the advanced small cancer in the middle thirds, and total gastrectomy with complete dissection of #1 to 13 nodes and sampling of #14, 16 nodes is indicated for cancer in the lower thirds.

Humans↗

[The analysis of prognosis of patients with gastric cancer with the nodal stage(N, n) and the number of involved lymph nodes].

Now we use the nodal grade (N, n) as a prognostic indicator in patients with gastric cancer according to the general rules for the gastric cancer study. But there are both of patients with good and poor prognosis in the same nodal grade. Then we analyzed the survival of patients with gastric cancer based on the nodal grade and the number involved lymph nodes, and discussed the new prognostic indicator with both of them. We classified the three groups based on the number of involved nodes as follows: 0.1-4.5-. There is the differences in survival between each pair of groups statistically. The relationship between the nodal grade (N, n) and the number of lymph node metastasis is that the survival of patients with involved nodes more than five is equal to the survival of the patients with high nodal grade and involved nodes 1-4. Therefore it suggest that the new grading consisting of them will be more better prognostic indicator.

Humans↗

[Prognostic factors of the gastric cancer patients without distant metastasis].

From 1946 to 1990, 10,485 patients with gastric cancer were been surgically treated in the Cancer Institute Hospital, Tokyo. Retrospectively, we analyzed prognostic factors, especially in those without distant metastasis. Prognosis of the patients with tumors which invaded the proper muscle layer improved dramatically (from 70% to 90%). However, patients who had advanced tumors with serosal invasion did not show good survived (from 20% to 40%). To improve the prognosis of patients with serosal positive gastric cancer, a new and effective prophylactic therapy for peritoneal recurrence is needed.

Humans↗

[Left upper abdominal evisceration for advanced gastric cancer].

To evaluate the clinical significance of the surgical procedure of left upper abdominal evisceration (LUAE), we analysed the prognosis of patients who received LUAE in the Cancer Institute Hospital from 1980 to 1990 using pair matching analysis. Survival benefits were observed in the patients with the tumor located in the upper or middle part of the stomach, and especially in those with Borrmann type 4 gastric cancer. Even in cases of peritoneal dissemination, patients who received LUAE survived longer than those with conventional total gastrectomy. These results indicated that LUAE should be a standard surgical approach for Bormann type 4 gastric cancer.

Aged↗

[The changes in the treatment of early gastric cancer--endoscopic mucosal resection and limited (nerve preserving) operation].

We have been trying to perform endoscopic mucosal resection (ER) since 1987, and limited operation since 1985 (nerve preserving operation since 1991) for early gastric cancer. 205 patients were performed ER from 1978 to 1990, 78 patients were performed limited operation from 1985 to 1993. We perform ER according to the indication as follows: 1) differentiated IIa type, size approximately 2 cm, 2) differentiated IIc type, size approximately 1cm, Ul(-), 3) undifferentiated IIc type, size approximately 5mm, Ul(-). And the indication of limited operation is the patients with intramucosal cancer and tumor size approximately 2cm. Up to date, we have never experienced recurrence of these patients undergone ER or limited operation. As to QOL, these therapy will be expected to improve QOL of early gastric cancer patients, especially per os and body weight loss after surgery.

Gastrectomy↗