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Biomedical subjects

S Sakurai

Publications and source records attributed to S Sakurai.

At least 199 records · Page 11Linked to original sources

Ecdysteroid synthesis and molting by the tobacco hornworm, Manduca sexta, in the absence of prothoracic glands.

When a pair of prothoracic glands (PGs) were removed from Manduca sexta pupae on the day of pupation, the hemolymph ecdysteroid titer remained at a low level. When a portion of the gland pair was extirpated from pupae after the critical period for prothoracicotropic hormone release, the maximum hemolymph ecdysteroid titer was reduced in proportion to the mass of the PGs removed. These findings clearly showed that the PGs in intact pupae are responsible for the elevated ecdysteroid titer required to elicit adult development on schedule. When brains were removed on the day of pupation, the initiation of adult development was delayed for weeks or months. In contrast, pupae whose PGs were removed on the day of pupation initiated development only 7 days late, indicating the existence of an additional source of pupal ecdysteroids. Further, abdomens of male M. sexta that were isolated on the day of pupation initiated adult development spontaneously within 70 days. The implantation of day 0 pupal brains into these isolated abdomens accelerated the initiation of adult development and elicited synchronous adult development. The hemolymph ecdysteroid titer of those isolated abdomens receiving implants of brains increased within 5 days and reached a maximum level of 1.5 micrograms/ml. The analysis of hemolymph ecdysteroids by reverse-phase HPLC revealed that ecdysone was the major moiety and that the ecdysteroid composition was similar to that of normal, intact pupae that had just initiated adult development. These results demonstrate that the PGs are not requisite for adult development. An increased hemolymph ecdysteroid titer was also observed in isolated abdomens from which the testes were removed and in abdomens devoid of their digestive tract. Indeed, in the latter case, the ecdysteroid titer attained much higher levels than those observed for abdomens with intact guts. Despite numerous attempts to identify the tissue(s) in the isolated abdomens responsible for the increase in ecdysteroid titer, its identity remains unknown.

Animals↗

Preferred tastes and opioid-modulated behaviors in neonatal rats.

Ten-day-old rats were given various tastants to ingest, independent of mother and suckling. Relative to water, the pups ingested significantly more saccharin (0.5%) and NaCl (2.5%) and less quinine (0.4%). Pretreatment with the opiate antagonist, naltrexone, had no effect on water or quinine intake but significantly reduced that of saccharin and NaCl. Furthermore, the preferred solutions of saccharin and NaCl given intraorally caused a decrease in ultrasonic vocalizations of isolated pups and in a separate experiment caused an analgesic response to heat. Both phenomena were reversible with naltrexone administration, suggesting that preferred tastes elicit an endogenous opioid response significantly affecting behaviors seen during isolation.

Animals↗

A bacteriological study of perforated duodenal ulcers.

Peritoneal fluid sampling and bacteriological examination were performed in 63 patients with perforated duodenal ulcers, and the results compared with those in 175 patients with other perforations. Bacterial culture was positive in 100 per cent of the patients whose perforations occurred in the colon, whereas it was positive in only 44.4 per cent of those with duodenal perforations, being negative in many cases when the interval from perforation to surgery was short. A mixed contamination with both aerobes and anaerobes was usually found in the cases of lower digestive tract perforation, and the isolates from duodenal perforations were uniquely aerobes in most cases. It is suggested that bacteria play a minor role in the pathogenesis of early stage duodenal perforation, which supports the technique of primary closure without indwelling drainage tubes during early stage operations following sufficient peritoneal lavage. Moreover, if the stomach is empty at the time of perforation and the peritonitis is localized, even conservative therapy seems possible, provided it is begun shortly after the perforation.

Adolescent↗

Cytokines in normal and abnormal parturition: elevated amniotic fluid interleukin-6 levels in women with premature rupture of membranes associated with intrauterine infection.

The participation of interleukin-6 (IL-6) in the pathophysiology of normal and abnormal human parturition was evaluated by determining IL-6 concentrations in amniotic fluid (AF). Biologically active IL-6 was determined (in U/ml) using the B9 hybridoma growth factor assay, while the concentrations of immunoreactive IL-6 species (in pg/ml) were assessed using a monoclonal antibody (moAb)-based ELISA. Two hundred and twenty-seven AF samples from women in normal labor and from those presenting with a clinical diagnosis of premature rupture of membranes (PROM) were assayed. In selected instances, IL-6 levels were evaluated simultaneously in AF and in maternal and fetal plasma. Women with a normal pregnancy had low titers of biologically active IL-6 in AF both at midtrimester (group 1, n = 27; median IL-6 concentration = 16 U/ml) and at term (group 2, n = 33; median = 15 U/ml). There was an increase in the IL-6 bioactivity in AF from women in normal labor at term (group 3, n = 40; median = 74 U/ml; p less than 0.001). In order to distinguish between the relative contributions of parturition per se and of intrauterine infection to the elevation of biologically active IL-6 levels in AF, IL-6 titers were compared in four different groups of women with PROM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Reflection as a cause of mid-systolic deceleration of pulmonary flow wave in dogs with acute pulmonary hypertension: comparison of pulmonary artery constriction with pulmonary embolisation.

STUDY OBJECTIVE: The aim was to examine whether mid-systolic deceleration of the pulmonary flow wave occurred in acute pulmonary hypertension due to pulmonary artery constriction and pulmonary embolisation, and if so whether it was related to reflection. DESIGN: Various degrees of pulmonary hypertension were induced by both pulmonary artery constriction and pulmonary embolisation in dogs. During control periods and during pulmonary artery constriction and pulmonary embolisation, pulmonary flow and pulmonary artery pressure were recorded, and the forward and backward (reflected) flow waves were separated from the measured pulmonary flow wave by the method of Westerhof et al. MATERIALS: 20 adult mongrel dogs were used and 10 dogs qualified for analysis. The other 10 dogs, which died before both interventions were completed, were excluded. MEASUREMENTS AND MAIN RESULTS: During pulmonary artery constriction, a distinct mid-systolic deceleration of the pulmonary flow wave was observed in five of the 10 dogs, while during pulmonary embolisation, no mid-systolic deceleration was found in these five dogs. The distinct deceleration of the pulmonary flow wave was related to a steep fall and early negative peak in the backward flow wave. CONCLUSION: Mid-systolic deceleration of pulmonary flow wave is likely to be related to reflection.

Acute Disease↗

Anionic carbohydrate groups of human thyroglobulin containing both phosphate and sulfate.

We showed previously that human thyroglobulin (hTG) contains anionic complex carbohydrate units with up to four sulfate groups, some containing both sulfate and sialic acid. Recent reports indicate that the carbohydrate units of hTG may also contain phosphate, but these reports are not all in accord. The purpose of this study was to confirm the presence of phosphate on the carbohydrate units of hTG and to determine whether phosphate coexists with other acidic moieties, such as sulfate and sialic acid, on the same carbohydrate units. Alkaline phosphatase and acid hydrolysis were used to detect phosphate on the sulfated carbohydrate units of hTG derived from normal and neoplastic tissues. Thyroid fragments from two patients were incubated for 16 h in [35S]sulfate-containing medium, and hTG was purified. Complex carbohydrates were released from hTG with endoglycosidase-F and analyzed at pH 2.2 on a HPLC ion exchange column. Sulfate-containing peaks were monitored by radioactivity, and sialic acid-containing ones were identified by their reduced charge after neuraminidase or acid treatment. None of the sulfate-labeled carbohydrate peaks shifted after alkaline phosphatase treatment alone, indicating that none of them contained phosphomonoesters. Several of the sulfate-labeled peaks shifted after acid hydrolysis, some to positions of decreased charge, due to removal of sialic acid, and some to positions of increased charge, suggesting the presence of phosphodiesters. The latter was confirmed by the observation that some of the newly formed peaks were susceptible to alkaline phosphatase digestion. Thus, acid hydrolysis converted phosphodiesters into alkaline phosphatase-susceptible phosphomonoesters, most likely mannose-6-phosphate. We conclude that some anionic complex carbohydrate units of hTG contain exclusively sulfate, while others contain combinations of sulfate, sialic acid, and phosphodiesters. Phosphodiesters are present in the sulfated carbohydrate units of hTG from normal as well as neoplastic thyroid tissue.

Alkaline Phosphatase↗

BOMM regimen for the treatment of advanced head and neck carcinoma.

Eighty patients with Stage III and IV head and neck cancer were treated with a four-drug regimen consisting of bleomycin, vincristine, methotrexate, and mitomycin-C (BOMM regimen). Of 69 patients evaluable for response, 7 complete and 40 partial responses were achieved, with an overall response rate of 68%. The median duration of response was 13 weeks (range 3-41 weeks). Anorexia, lassitude, febrile reactions, and myelosuppression were major side effects. The BOMM regimen produced a response rate significantly better than VCR, BLM, and MTx combination (VBM) which we previously reported with improved response duration. This study demonstrates that the BOMM regimen, which can be administered on an outpatient basis, achieved a response rate comparable to cisplatin-containing regimens. The BOMM regimen may be beneficial to patients with poor general condition and/or marginal renal dysfunction who are in high risk of toxicity-associated cisplatin-containing regimens.

Adult↗

[The effects of teacher stimulation on student learning motivation].

The purpose of this study was to compare the effects of two types of teacher stimulation on 1) learning motivation of students who were poor in mathematics and 2) the students' impression of the teachers. One type of teacher stimulation was the encouragement of students who were poor in mathematics to make more effort because they had good ability but their ability was not yet realized. The other type of teacher stimulation was the encouragement of the students to exert themselves because of their previous lack of effort. A questionnaire, including the scenario describing the two types of teacher stimulation and several questions about the students' motivation and impression of the teachers, was administered to 378 elementary school, junior high school, and college students. The former type of teacher stimulation was partially more effective in the motivation of students and also fully more effective in the students' impression of the teachers than the latter type of teacher stimulation.

Adolescent↗

[Comparison of two hours' biofiltration and four hours' bicarbonate hemodialysis by multiple clinical parameters].

Ten uremic patients maintained stable on regular dialysis treatment participated in a comparison study of 2 hours' biofiltration and 4 hours' bicarbonate hemodialysis with informed consents. In biofiltration, ultrafiltrate was replaced by a solution consisting of Na 145 mEq/l, HCO3- 100 and Cl 45 at the infusion rate 2.51/hour. Dialysate composition was Na 130-149 mEq/l, K 1.0, Cl 119, Ca 2.5, Mg 0.5, CH3COO- 15 and glucose 200 mg/dl. Hemodiafilter was F80, polysulphone, 1.9 m2, manufactured by Fresenius Co. Ltd. Blood flow rate was 5 ml/min/kg.body.weight to keep urea index (Kt/V) over 1.0. B-A-B' comparison was designed in which B and B' stand for 4 hours' bicarbonate hemodialysis while A for 2 hours' biofiltration, 3 times per week for 2 months, respectively. It was intended to find out if there are aggravations of clinical parameters in A after B and/or improvements in B' after A in view of evaluation of optimum for 2 hours' biofiltration. One patient was withdrawn from biofiltration at 15th treatment in A because of frequent muscular twitchings. Others finished the whole program, thus making drop-out rate 10%. No significant differences were observed in the following parameters between B and A and between A and B': cardiothoratic ratio, pre-treatment blood pressure, human atrial natriuretic hormone, cardiovascular dynamics, total protein, BUN, serum creatinine, uric acid, beta 2 microglobulin, blood counts, blood gas analysis, electrolytes, alkaline-phosphatase, PTH-C, protein catabolic rate (PCR), lipids and liver functions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Usefulness of the pulse oximeter as a respiratory monitor during intravenous sedation.

During intravenous sedation, the pulse oximeter was applied as a respiratory monitor to 17 patients (Physical status classification of the American Society of Anesthesiologists, Class I-II) who were to have oral surgical operations, and the changes in arterial saturation of oxygen (SaO2) was observed consecutively. SaO2 dropped after administration of sedative agents in each case; there was some individual variation. Respiratory depression during sedation was evaluated from arterial blood gas analysis. The reduction in SaO2 caused by surgical manipulations was also noted. Furthermore, arterial partial pressures of oxygen (PaO2) and saturation calculated from PaO2 (SAT) measured from blood gas analysis were compared with SaO2 measured by the pulse oximeter. Both PaO2 and SAT correlated well with SaO2. The differences between SAT and SaO2 exceeded the range of error (+/- 2%) in many cases after the administration of sedative agents. These results suggest that the pulse oximeter is useful as a respiratory monitor during oral surgery. However, the pulse oximeter gives incorrect SaO2 readings in the presence of abnormal hemoglobin due to medication with nitrites or smoking habit.

Anesthesia, Dental↗

[Effect of posture on pharyngeal area measured by acoustic reflection technique].

Patients with obstructive sleep apnea (OSA) have a smaller pharyngeal area (PA) and higher compliance than normal subjects. The apnea-hypopnea index (AHI) in OSA patients determined by polysomnographic study was greater in the supine than lateral position. Recently there have been reports of reduction in the PA by the acoustic reflection technique (ART) in the supine position. However, there has been no report on the PA measured by ART in the lateral position which is important in the treatment of OSA. To evaluate differences in the PA with posture changes, we measured the PA in 41 normal subjects (11 males and 30 females) in the sitting, lateral and supine positions by ART. The average PA in the sitting position in the males and females was 3.8 +/- 0.6 cm2, and 3.3 +/- 0.5 cm2, respectively. The average PA in the lateral position in the males and females was 3.5 +/- 0.6 cm2, and 3.1 +/- 0.5 cm2, respectively. The average PA in the supine position in the males and females was 2.9 +/- 0.5 cm2, and 2.7 +/- 0.4 cm2, respectively. PA in the sitting position correlated well with body surface area (BSA). The average PA in both the males and females was significantly smaller in the supine than in the sitting position. The average PA in the lateral position in both males and females was significantly smaller than that in the sitting position and was significantly larger than that in the supine position. Decrease in PA with posture (from sitting to lateral) in the males (9.2 +/- 5.5%) was similar to that in the female (5.7 +/- 5.4%). Decrease in PA with posture (from sitting to supine) was significantly larger in male (24.4 +/- 9.5%) than in female (16.6 +/- 6.8%). We conclude that the decrease of PA in the supine position is ameliorated in the lateral position in normal subjects. Lateral position may be the preferred sleeping position in snoring or OSA patients.

Adult↗

An enzyme-linked immunosorbent assay for the measurement of human interleukin-6.

An enzyme-linked immunosorbent assay has been developed to measure human interleukin-6. The assay, based on the avidin-biotin amplified two-step sandwich method, is quick (requiring 4.5 h), sensitive (detecting 9.5 pg/ml) and satisfactory in reproducibility and specificity. It shows good correspondence with the results of bioassays, and it is not affected by serum and plasma components. These results indicate that this ELISA is suitable for application to clinical samples, which is a major advantage over the widely used bioassays.

Animals↗

Prothoracic gland synthesis of 3-dehydroecdysone and its hemolymph 3 beta-reductase mediated conversion to ecdysone in representative insects.

The prothoracic glands of a variety of insects were tested for their ability to synthesize ecdysteroids in vitro. More specifically, they were evaluated for their ability to produce 3-dehydroecdysone and ecdysone using both radioimmunoassay and reverse phase high performance liquid chromatography. Three categories of insect prothoracic glands were noted: a) those producing much more 3-dehydroecdysone than ecdysone; b) glands synthesizing almost equivalent amounts of each of these two ecdysteroids; c) prothoracic glands that yielded more ecdysone than 3-dehydroecdysone. In addition, the 3-oxoecdysteroid 3 beta-reductase activity of the hemolymph of these insects was evaluated for its ability to convert 3-dehydroecdysone to ecdysone. The lepidopteran species tested yielded the most potent enzyme activity, although activity was demonstrated in members of other orders. These data indicate that the dehydroecdysone-ecdysone axis is not restricted to moths and butterflies.

3-Hydroxysteroid Dehydrogenases↗

[Evaluation of non-surgical treatments of hepatocellular carcinoma--investigation of the cases with long and short survivals after treatment].

One hundred and one cases of hepatocellular carcinoma (HCC) treated in Maebashi Red Cross Hospital from May 1984 to August 1987 were classified according to the therapy and progression of the disease and were investigated on their prognosis. Furthermore, "long survived group" in which, patients survived for more than one year were compared with "short survived group" in which patients died within one month after non-surgical treatment. In operated patients, the prognosis was the best, but the rate of operable cases was only 13.9%. In patients with stage IV, one year survival rate was significantly low. In patients with portal trunk invasion (Vp4), or with Child C that was the poorest functional reserve of the liver, one year survival rate was also significantly low in comparison with patients with other stages or other Child's classification. In HCC patients treated with transcatheter arterial embolization (TAE), the prognosis tended to be poor as stage and portal invasion progressed, but in regard to reserve function of the liver, the prognosis was not so poor in patients of Child C significantly as in cases of A or B. The comparisons between long and short survived group were as follows. a) In 17 cases belong to long survived group, mean survival period was 24 months and the longest one was 4 years and 10 months. On the other hand, in 10 cases belong to short survived group, mean survival period was 17 days, the shortest one was 3 days. b) The main reason of inoperability in long survived group was progression of the tumor. Complications such as diabetes mellitus, advanced age and rejection of treatment by the patient were the other reasons of in operability. In almost half of the patients in short survived group, the tumor progression and low functional reserve of liver were found in 4 patients. c) In short survived group, esophageal varices were more common and functional reserve of the liver was poorer than in long survived group. In short survived group, LDH and total bilirubin were significantly higher than those of long survived group, but there was no significant differences in transaminase value and ICG retention in 15 minutes. d) In short survived group, extent of the tumor in liver and portal invasion were advanced. Three cases of this group (30%) had distant metastasis. e) In long survived group, the main reason of death was hepatic failure. Renal failure, or pulmonary complications were also found in short survived group.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗