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Biomedical subjects

S Ohashi

Publications and source records attributed to S Ohashi.

At least 91 records · Page 5Linked to original sources

Thoracoscopic enucleation of a large leiomyoma located on the left side of the esophageal wall.

Thoracoscopic enucleation through the right thorax was successfully performed for a large leiomyoma located on the left wall of the upper-middle esophagus. Using intraoperative esophagoscopy, the exact location of the tumor was identified by trans-illumination. Two sling tapes passed around teh esophagus made the procedure as easy as that for tumor located on the right wall of the esophagus. We considered that the thoracoscopic approach through the right thorax can be applied to various types of esophageal leiomyoma, even a large one located on the left side of the esophagus.

Adult↗

Laparoscopic intragastric surgery for gastric leiomyoma.

Laparoscopic intragastric surgery (LIGS) was performed on a 63-year-old man with a gastric leiomyoma adjacent to the cardia. Because the tumor was about 5 cm in maximum diameter and showed ulceration, the possibility that the tumor was a leiomyosarcoma could not be ruled out preoperatively. Conventionally, major surgery has been performed on patients with a tumor located near the cardia, although it was not always malignant. Enucleation by LIGS enabled us to avoid excessive invasiveness and provided a favorable result. LIGS may be an appropriate new, minimally-invasive operation for gastric myogenic tumors and should be considered for such cases.

Humans↗

Childhood bronchial mucoepidermoid tumors.

A very rare case of a childhood bronchial mucoepidermoid tumor is presented. A 4-year-old girl was hospitalized with prolonged pneumonia. Computed tomography of the chest showed a tumor with calcifications in the right upper lobe. Subsequently, the patient underwent right upper lobectomy. Histologically, the tumor was a low-grade mucoepidermoid tumor originating from the bronchus. Three years postoperatively there has been no evidence of disease. A review of the literature indicates that 30 cases of bronchial mucoepidermoid tumors in children have been reported. Symptoms result from associated bronchial obstruction. Children with recurrent or prolonged pneumonia should undergo aggressive diagnostic investigation by chest tomography or bronchoscopy. Appropriate therapy for childhood bronchial mucoepidermoid tumor is total resection of the lesion while sacrificing as little of the normal lung tissue as possible.

Airway Obstruction↗

Effects of growth hormone (GH)-releasing hormone and its analogs on GH secretion from cultured adenohypophysial cells in cattle.

The effects of the human growth hormone (GH)-releasing hormone (hGRF(1-44)-NH2: hGRF-44), bovine GRF (bGRF(1-44)-NH2: bGRF-44), and their analogs (hGRF(1-29)-NH2, [D-Ala2]- hGRF(1-29)-NH2, bGRF(1-29)-NH2,[D-Ala2,Ala15]-bGRF(1-29)-NH2) as well as rat GRF(rGRF) on bovine GH release from anterior pituitary (AP) cells were studied in vitro in steers. The AP cells were incubated for 2 hr with the GRFs after preincubation for 3.5 d. Both of the hGRF-44 and hGRF(1-29)-NH2 (hGRF-29) significantly stimulated GH release from cultured cells at doses from 10(-14) to 10(-8)M (P < 0.01). The analog [D-Ala2]-hGRF-29 significantly induced GH release in media at doses from 10(-18) to 10(-8) M (P < 0.01). The bGRF-44, bGRF(1-29)-NH2 (bGRF-29), and [D-Ala2, Ala15]-bGRF-29 significantly induced GH release in media at doses as low as 10(-18), 10(-17), and 10(-16)M, respectively (P < 0.01). At doses from 10(-11) to 10(-8)M, there were no significant differences in GH-releasing potency between the hGRFs and bGRFs. The rGRF significantly stimulated GH release at doses ranging from 10(-14) to 10(-8) M (P < 0.01). The linear regression tests showed that the hGRFs, bGRFs, and rGRF, at doses from 10(-14) to 10(-8)M, induced GH release in a dose-related manner (P < 0.01). These results suggest that the hGRF, bGRF, and their analogs, as well as rGRF, are potent secretagogues of GH release from adenohypophysial cells in vitro in cattle.

Animals↗

Chi-star, a chi-related 11-mer sequence partially active in an E. coli recC1004 strain.

BACKGROUND: chi sequence (5'GCTGGTGG) of Escherichia coli was first identified as a site that increased the plaque size of bacteriophage lambda. Subsequent studies showed that this site is responsible for both the attenuation ofRecBCD exonuclease activity and the promotion of RecA, RecBCD-mediated recombination. It is known that bacteriophage lambda containing the chi site makes very small plaques on a recC* (recC1004) mutant because chi is not recognized by the RecBC*D mutant enzyme. RESULTS: We cloned E. coli chromosomal fragments in lambda which allowed lambda to form larger plaques on this recC1004 mutant. The fragments were found to share a chi-like 11-mer sequence, 5'GCTGGTGCTCG. Substitution of these fragments with a synthetic 11-mer of this sequence and single-base-pair substitution analysis of its last four nucleotides demonstrated that this sequence is both necessary and sufficient for the observed activity. The sequence, designated X* (chi-star), protected rolling-circle DNA replication in the recC1004 mutant and in the recBCD+ strain, most likely because it attenuated the exonuclease activity of the RecBC*D and RecBCD+ enzyme. chi-star, did not significantly stimulate lambda recombination in two assays. CONCLUSION: We have discovered that a mutant RecBCD enzyme responds, in vivo, to a longer chi variant.

Bacteriophage lambda↗

Clustering of chi sequence in Escherichia coli genome.

An 8-mer DNA sequence called chi (5'-GCTGGTGG) is present on the Escherichia coli chromosome at a high frequency. It is responsible for both the attenuation of RecBCD exonuclease activity and the promotion of RecABCD-mediated homologous recombination. chi was first identified as a site that increased plaque size of bacteriophage lambda. lambda containing chi makes very small plaques on a recC* (recC1004) mutant because chi is poorly recognized by the RecBC*D mutant enzyme. We cloned E. coli chromosomal fragments in lambda that allowed lambda to form larger plaques on this recC* mutant as well as on the rec+ parent. One identified fragment contained a cluster of two copies of chi and several chi-like sequences with the same orientation. It increased recombination in the rec+ strain more than a fragment with one chi did. This fragment was within the rep gene, whose helicase product is known to be required for growth in the absence of functional RecBCD enzyme. The possibility that RecBCD enzyme might interact both with the rep gene and its product is discussed. Many of the other chi clusters identified in the E. coli genome database lie within genes for membrane proteins. The possible significance of these findings is discussed.

Bacteriophage lambda↗

Embolic materials for endovascular treatment of cerebral lesions.

Recently developed soft microcatheters can be maneuvered endovascularly into the brain, permitting treatment of lesions without conventional neurosurgery. Progress in biomaterial science has contributed significantly to the development of this new therapeutic modality termed intravascular neurosurgery or interventional neuroradiology. Although embolic materials play an important role, ideal materials have yet to be devised. Various embolic materials in clinical use are reviewed, such as cyanoacrylates, ethylene-vinyl alcohol copolymer mixtures, Ethibloc, ethanol, estrogen, poly(vinyl acetate), cellulose acetate polymer, poly(vinyl alcohol), gelatin sponges, microfibrillar collagen, surgical silk sutures, detachable balloons, and coils. The materials are reviewed in the context of treatment application for various brain lesions, such as arteriovenous malformations, cerebral aneurysms, and head and neck tumors. Further developments in biomaterial polymer science can bring about progress against brain diseases.

Catheterization, Peripheral↗

Protective efficacy of an affinity-purified hemolysin vaccine against experimental swine pleuropneumonia.

Protective efficacy of Actinobacillus pleuropneumoniae extracellular hemolytic toxins, RTX-toxin I (Apx I) and Apx II, was evaluated in pigs. The hemolysins were purified from culture supernatant of A. pleuropneumoniae strain HA-337, serotype 1 by immunoaffinity chromatography using a monoclonal antibody specific for Apx I or Apx II as ligand. Four pigs were vaccinated with the purified hemolysins absorbed on aluminum phosphate gel adjuvant. Four pigs of a control group were given placebo. Hemolysin-neutralizing antibodies were detected only in vaccinated group after booster injection. One of four control pigs died following an aerosol challenge with the homologous strain, and three surviving pigs developed serious clinical signs of pneumonia and had extensive lung lesions. In contrast, there was no mortality in vaccinated group. Only transient hyperthermia was observed in two vaccinated pigs after challenge. A necropsy, two vaccinated pigs had slight localized pulmonary lesions, though the remaining two had no lung lesions at all. These results indicate that the hemolysin vaccine made of Apx I and Apx II has good protective activity against swine pleuropneumonia caused by A. pleuropneumoniae serotype.

Actinobacillus Infections↗

Comparison of commercial isotonic fluids intravenously administered to rehydrate fasted bullocks.

Holstein bullocks were used in this study to compare the effectiveness of five commercial parenteral fluids (saline IS, Hartmann's IH, 5%-glucose 5G, Ringers IR, and 1/2 Ringer's and 2.5% glucose combination solutions RG) in correcting the disturbances associated with dehydration induced by fasting for 48 hr. These five commercial fluids (30 ml/kg) were given to bullocks with dehydration induced by fasting for 48 hr. Arterial and venous blood samples were taken before fasting, and at 0, 15, 30, 45, 60, 90, 120, 240, 360 min, and 24 hr after initiation of fluid administration. Fasting for 48 hr induced significant reductions in body weight and relative plasma volume (rPV), of approximately 7.72 and 21.93%, respectively. During the administration period, rPV showed a progressive increase from approximately 88.1% after fasting to 113.0% with no significantly differences between groups. A rapid decrease of rPV when fluid administration has been finished was observed in the 5G and RG groups. The results of the fluid administration trial showed that the 1/2 Ringer's and 2.5% glucose combination solution inhibited the acidification of the blood, produced no change in the electrolyte balance of serum, and induced a proper reabsorption rate of glucose in the renals, and was therefore considered the best choice for the rehydration of adult cattle which have had no appetite for over 2 days.

Animals↗

Effects of growth hormone-releasing hormone (GRF) analogs, bovine and rat GRF on growth hormone secretion in cattle in vivo.

Effects of bovine and human growth hormone-releasing hormone (GRF) analogs (bGRF(1-29)-NH2: bGRF-29, [D-Ala2, Ala15]-bGRF-29, [D-Ala2]-hGRF(1-29)-NH2: [D-Ala2]-hGRF-29), bovine GRF (bGRF(1-44)-NH2: bGRF-44), as well as rat GRF (rGRF) on GH release were studied in female calves. Intravenous (i.v.) bolus injections of 0.25 microg/kg BW of bGRF-29, [D-Ala2, Ala15]-bGRF-29, and [D-Ala2]-hGRF-29 stimulated GH release. Plasma GH levels began to rise 10 min after the injection of each peptide, and significant increases in GH concentrations were obtained at 60, 180 and 150 min after the injection of bGRF-29, [D-Ala2, Ala15]-bGRF-29 and [D-Ala2]-hGRF-29, respectively. The concentrations of GH 80 min after the injection of [D-Ala2, Ala15]-bGRF-29 were significantly higher than those after the injection of [D-Ala2]-hGRF-29 (except at 80 and 90 min) or bGRF-29. The i.v. bolus injections of 0.25 microg/kg BW of bGRF-44 and rGRF stimulated GH release, and the GH-releasing potency of rGRF was approximately equal to that of bGRF-44. The plasma GH responses to the repeated i.v. injection of bGRF-29 or [D-Ala2, Ala15]-bGRF-29 at 2-h intervals were examined. bGRF-29 acutely increased plasma GH levels after each injection, and the high GH levels decreased to the basal values within 2 h. In contrast, high GH levels induced by [D-Ala2, Ala15]-bGRF-29 were gradually decreased but not lowered to basal values throughout the experiment. These results show that [D-Ala2, Ala15]-bGRF-29 has longer-lasting and greater GH-releasing activity than the other GRF analogs in female calves, and the GH-releasing potency of rat GRF is approximately equal to that of bovine GRF in cattle in vivo.

Animals↗

Laparoscopic colpopoiesis using sigmoid colon.

A new technique for colpopoiesis using sigmoid colon autograft by a laparoscopic surgery is introduced for the first time. This technique requires advanced skills perform and may be the choice in respect to naturalness and permanency of the neovagina with minimum invasion.

Adult↗

[Percutaneous transluminal coronary angioplasty in patients with multivessel coronary disease: does complete revascularization improve the long-term survival?].

The influence of complete revascularization on long-term outcome of patients with multivessel coronary artery disease undergoing percutaneous transluminal coronary angioplasty (PTCA) was determined by analysis of 10-year survival in 167 consecutive patients treated at Juntendo University Hospital during 1984-1993. Forty-nine patients were completely revascularized and 118 had incomplete revascularization according to the anatomical classification. Among patients with anatomically incomplete revascularization, 56 were categorized as functionally adequate revascularization and 62 as functionally inadequate revascularization according to Faxon's criteria. Baseline characteristics showed incompletely revascularized patients had a higher incidence of prior myocardial infarction triple-vessel disease and/or chronic total occlusion in at least one lesion. The 10-year survival was slightly better in patients with complete (100%) than in those with incomplete revascularization (79%), but not statistically significant (p = 0.089). Event-free survival was not significantly different between the two groups. However, the need for coronary artery bypass surgery was higher in the incomplete revascularization group than that in the complete revascularization group (100% vs 81%, p = 0.013). The influence of the degree of functional revascularization on outcome was not clear in the present study. Long-term survival appeared to be better in patients with complete revascularization than that in patients with incomplete revascularization, but even in the latter, coronary artery bypass grafting in the later period could improve outcome. The effect of functional revascularization status should be further investigated in a larger population.

Angioplasty, Balloon, Coronary↗

Thoracoscopic treatment of esophagobronchial fistula with esophageal diverticulum.

Thoracoscopic fistulectomy and diverticulectomy for esophagobronchial fistula with esophageal diverticulum were performed on a 49-year-old-woman. The neck of the diverticulum and the fistula were divided with endo-stapling technique. Intraoperative esophagoscopy was found to be useful for the definite localization and complete excision of the fistula and the diverticulum and the avoidance of stenosis of the esophagus. To avoid the recurrence of fistula, a pedicle of viable mediastinal pleura was interposed between esophageal and bronchial closures. Postoperative course was uneventful, and the complete relief of symptom was experienced for a period of 10 months after the operation. It is to be considered that the present thoracoscopic procedure with intraoperative esophagoscopy can be used as a standard operative procedure for esophagobronchial fistula with esophageal diverticulum.

Bronchial Fistula↗

Human V delta 2+ gamma delta T-cell tolerance to foreign antigens of Toxoplasma gondii.

Little is known about the mechanisms involved in human gammadelta T-cell tolerance to self or to foreign antigens. Patients with congenital toxoplasmosis offer a unique opportunity to examine Vdelta2+ gammadelta T-cell tolerance. Analysis of gammadelta T cells in patients with congenital toxoplasmosis revealed evidence for anergy of these cells with or without clonal Vdelta2+ gammadelta T-cell expansion in the acute phase of the Toxoplasma infection. T cells in general were unresponsive and did not proliferate upon exposure to mitogens or to Toxoplasma lysate antigens or in response to live Toxoplasma-infected cells when the congenitally infected infants were 1 month of age, and they exhibited selective anergy to Toxoplasma lysate antigens and live Toxoplasma-infected cells when the infants were aged 5 months. During the chronic phase of congenital toxoplasmosis in the patients who were more than I year of age, the repertoires of the gammadelta T-cell receptors were found to be within normal ranges. In addition, in the chronic phase, the gammadelta T cells proliferated and secreted gamma-interferon in response to exposure to live Toxoplasmia-infected cells. By contrast, alphabeta T cells remained anergic. Vdelta2+ gammadelta T cells have been considered to undergo extrathymic maturation and thus to be subject to development of peripheral tolerance. Our findings indicate that Vdelta2+ gammadelta T-cell tolerance was lost in these infected infants earlier than alphabeta T-cell tolerance. These findings suggest that gammadelta T cells play a role in protection against Toxoplasma gondii in the chronic phase when congenitally infected children are more than 1 year of age, especially in those in whom alphabeta T cells continue to exhibit deficits in specific immune responses to Toxoplasma antigens.

Acute Disease↗

Intraoperative manometry during laparoscopic operation for esophageal achalasia: does pneumoperitoneum affect manometry?

The effects of pneumoperitoneum on the lower esophageal sphincter (LES) were evaluated during laparoscopic operation for esophageal achalasia. Intraoperative manometry was performed in three patients who underwent laparoscopic cardiomyectomy with Dor's fundoplication and five patients who underwent laparoscopic cholecystectomy (LC). The LES pressure and the length of the high-pressure zone (HPZ) did not change during pneumoperitoneum in either the achalasia and the LC group. In the achalasia group the LES pressure was sufficiently decreased following completion of cardiomyectomy, and the length of the HPZ was found to be sufficiently long after completion of fundoplication. The postoperative courses of the achalasia patients were uneventful, and they have had no symptoms of achalasia or gastroesophageal reflux since the operation. Accordingly, intraoperative manometry during 12 mmHg pneumoperitoneum was considered to be available for laparoscopic surgery for esophageal achalasia.

Adult↗

Laparoscopic reconstruction of vagina using sigmoid autograft.

With the advent of advanced laparoscopic techniques in surgery, new applications have been found, which have expanded the role of laparoscopy in the gynecological field. The aim of this paper is to introduce our laparoscopic technique of taking a sigmoid colon autograft for colpopoiesis in a patient with congenital agenesis of the vagina. This technique is less invasive and is easy to perform, and it may be the best choice of operation in respect to the naturalness and the permanency of the vagina that results. The success of this laparoscopic technique of taking a sigmoid autograft for colpopoiesis suggests diverse possible applications in the future.

Adult↗