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Biomedical subjects

K Fukushima

Publications and source records attributed to K Fukushima.

At least 307 records · Page 17Linked to original sources
PubMed1995

Proton NMR spectroscopic studies of serum as an aid to perioperative cellular metabolic monitoring.

Perioperative concentration changes of cellular metabolites in serum were studied by proton NMR spectroscopy in four cancer patients who underwent tumorectomies under general anesthesia. In proton NMR spectra of serum, the resonances assignable to fatty acid in lipoprotein, lactate, alanine, glucose, glycoprotein and other metabolites were observed. The concentrations of fatty acid and alanine did not show significant changes during the operations compared with those in healthy volunteers. The concentrations of lactate, glucose and glycoprotein increased during the operations above the concentration ranges in the control subjects. The time-course of concentration change for lactate, glucose and glycoprotein was roughly classified into two patterns: i) the maximums of lactate and glucose concentration were observed in the latter halves or at the ends of the operations; ii) the maximums of glycoprotein concentrations were observed three hours after the incision, regardless of the operative time. The results showed cellular metabolic changes became larger as the operations proceeded responding to surgical stress. Prompt cellular metabolic monitoring is indispensable for the screening of cellular metabolic disorders caused by excessive surgical stress and proton NMR spectroscopy can be a new tool for monitoring perioperative cellular metabolism.

Adult↗
PubMed1995

[Air pollution by sevoflurane in operating room and serum and urine inorganic fluoride of anesthetists].

Since lower blood-gas partition coefficient of sevoflurane provides rapid induction and emergence from anesthesia, sevoflurane has been used widely for inhalational anesthesia. However, because higher minimum alveolar concentration of sevoflurane requires a large dosage of anesthetic than other volatile anesthetics, air pollution with sevoflurane in the operating room might be of great concern. Anesthetists may keep inhaling the low concentration of anesthetics every day, even though scavenging system is equipped in the operating room. The purpose of this study is to evaluate the effects on anesthetists of the low concentration of anesthetics by measuring the inorganic fluoride concentration in the urine and serum of anesthetists and operating room nurses. Healthy 29 anesthesiologists and two operating room nurses were studied. Informed consent was obtained. Inorganic fluoride ions in the serum and urine were measured. Simultaneously sevoflurane concentration in operating room was measured in three operating rooms, at two places in the corridor and in the recovery room. Sevoflurane concentrations in three operating rooms were 1.22 ppm, 2.13 ppm and 6.05 ppm respectively. Concentration in the recovery room was 0.544 ppm. Serum and urine concentrations of inorganic fluoride were 1.1 +/- 0.1 mumol.l-1 and 36.2 +/- 17.1 mumol.l-1, respectively (mean +/- SD). Serum concentration of inorganic fluoride was within normal ranges. Although it is possible that fluoride concentration in urine is influenced by urine volume and a half of fluoride deposits in bone, no abnormal values in urine were found in this study. These results suggest that long term exposure to low concentration of sevoflurane and isoflurane causes no significant increase in their metabolites in operating room staffs.

Adult↗
PubMed1995

[Augmentation by succinylcholine of the neuromuscular blocking effect of vecuronium in children].

To evaluate the influence of succinylcholine (Scc) on the neuromuscular blocking effect of subsequently administered vecuronium in children, 30 patients aged 2-14 years scheduled for elective surgery were studied after obtaining the informed consent from the parents. Anesthesia was induced with inhalation of sevoflurane, nitrous oxide and oxygen. T1 of the adductor pollicis muscle to ulnar nerve stimulation elicited by train of four stimulation at 2 Hz was monitored continuously by an acceleration transducer. The patients were divided into two groups; group V (16 patients) received vecuronium (0.03 mg.kg-1) and group SV (14 patients) received vecuronium (0.03 mg.kg-1) after 100% recovery of twitch from neuromuscular blockade induced with Scc (1.0 mg.kg-1). Short onset of action and potentiation of maximal block were demonstrated in group SV. After vecuronium administration, a complete suppression of T1 was observed in 8 patients of group SV and only 1 patient of group V. The present study demonstrates that the neuromuscular blockade of vecuronium can be potentiated with the prior administration of Scc in pediatric patients.

Adolescent↗
PubMed1995

GSH-independent denitration of organic nitrate esters in rabbit hepatic and vascular cytosol.

The denitration of organic nitrate esters in rabbit hepatic cytosol was characterized. Sephadex G-200 chromatography of ammonium sulfate precipitate (40-80%) from hepatic cytosol demonstrated the presence of two distinct activities (peak I and peak II) responsible for the denitration of nitroglycerin (NTG) and isosorbide dinitrate (ISDN). The denitration of peak I required dithiothreitol (DTT), but not glutathione (GSH), and was not inhibited by S-alkyl GSH, an inhibitor of glutathione S-transferase (GST). Whereas, the denitration activity of peak II was potentiated by GSH, and was inhibited by S-alkyl GSH. These results strongly suggest that the denitration of organic nitrate esters, such as NTG and ISDN, can be catalyzed by at least two enzymes, GSH-independent denitration (peak I) and the GSH-dependent denitration (peak II, GST), in rabbit hepatic cytosol. The denitration activity of peak I was inhibited by SH-modified reagent, indicating that free thiol(s) is (are) critical for expression of the denitration activity. Also, in rabbit vascular cytosol, the cofactor requirement for denitration and response to S-hexyl GSH suggest the participation of GSH-independent enzyme which is responsible for the denitration of organic nitrate esters.

Animals↗
PubMed1995

Regulation of bile acid synthesis in the rat: relationship between hepatic cholesterol 7 alpha-hydroxylase activity and portal bile acids.

Bile acid biosynthesis has been believed to be regulated by negative feedback control; however, recent experiments have cast considerable doubts on the concept. The aim of the study was to examine the consensus of the negative feedback regulation of bile acids by clarifying the correlation between the portal bile acids and the rate-limiting enzyme of bile acid biosynthesis, hepatic microsomal cholesterol 7 alpha-hydroxylase. We measured the enzyme activity and the portal bile acids in male Wistar rats that were orally administered three different bile acids or cholestyramine for 2 weeks. The serum level of 7 alpha-hydroxycholesterol was also determined to verify whether it would be a parameter of bile acid synthesis rate in the rat. The activity of cholesterol 7 alpha-hydroxylase increased about threefold in rats treated with cholestyramine when compared with controls. On the other hand, in rats fed ursodeoxycholic, chenodeoxycholic, and deoxycholic acids, the enzyme activities decreased to 40%, 26%, and 28%, respectively. Treatment with cholestyramine had no significant effect on the portal bile acid concentration. Administration of ursodeoxycholic and chenodeoxycholic acids resulted in a significant increase in the concentration of portal bile acids, whereas deoxycholic acid feeding did not significantly affect it. In the control group, conjugated cholic acid constituted a major part of the portal bile acids while the administered bile acid and its metabolites became predominant in each bile acid feeding group. Treatment with ursodeoxycholic acid made the portal bile acids more hydrophilic, but, by contrast, administration of chenodeoxycholic, deoxycholic acids, and cholestyramine made the portal bile acids more hydrophobic.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1995

[Effects of nitrous oxide on electroencephalographic activity during sevoflurane anesthesia: a zero-crossing analysis].

We have investigated the influence of nitrous oxide (N2O) on central nervous system (CNS) during sevoflurane anesthesia by using zero-crossing method of EEG in 31 patients. The study was divided into three parts: Study 1 (n = 18), Study 2 (n = 6) and Study 3 (n = 7). (Study 1) After induction of anesthesia, sevoflurane 1.0 % in oxygen (O2), and sevoflurane 1.0 % with 67 % N2O in O2 were given to the patients sequentially in a random fashion, and EEG was recorded. (Study 2) Sevoflurane 1.7 % in O2, and sevoflurane 0.7 % with 67 % N2O in O2, which were considered to be the same anesthetic depth (= sevoflurane 1 MAC), were inhaled, and EEG was recorded in the same manner as in the study 1. (Study 3) We compared the effects of N2O on EEG during intravenous administration of fentanyl and midazolam with 67 % N2O, and without N2O, and EEG was recorded in the same manner. In all studies, percentage of each frequency range (delta, theta, alpha, beta) and average frequency were calculated by zero-crossing method. During sevoflurane anesthesia, the EEG activity was decelerated with N2O, depending on minimum alveolar concentration (MAC). But there were no significant changes in EEG activity of the patient with and those without N2O during intravenous anesthesia. We concluded that the influences of N2O on CNS can be evaluated by quantitative analysis of EEG.

Adult↗
PubMed1994

Voluntary control of saccadic eye movement in patients with frontal cortical lesions and parkinsonian patients in comparison with that in schizophrenics.

To investigate whether the abnormalities of antisaccades in schizophrenics could be explained by a dysfunction of the frontal cortex, we examined 10 patients with frontal cortical lesions and 22 patients with idiopathic Parkinson's disease with mild symptoms (Yahr I-II) using the same tasks, and compared the results with those obtained in schizophrenics. The frontal patients with lesions covering the frontal eye field and prefrontal cortex showed more errors, longer latencies, and lower peak velocities in the antisaccade task, despite giving normal results in the visually guided saccade task. This was similar to the results observed in schizophrenics. Parkinsonian patients did not consistently show a significant difference in the antisaccade task. These results indicate specific abnormalities of antisaccades in schizophrenics and patients with frontal cortical lesions but not consistently in Parkinsonian patients. This suggests that the abnormalities of antisaccades in schizophrenics might be explained by a frontal cortical dysfunction.

Adult↗
PubMed1994

The transition of alpha-helix to beta-structure of poly(L-lysine) induced by phosphatidic acid vesicles and its kinetics at alkaline pH.

Static and dynamic circular dichroism (CD) measurements were carried out for poly(L-lysine) in suspensions of dilauroylphosphatidic acid (DLPA) vesicles at alkaline pH (8-11.5). The static experiments demonstrated that the alpha-helix of poly(L-lysine) induced by deprotonation in alkaline solutions is transformed to beta-structure by the addition of DLPA vesicles. Stopped-flow CD measurements for such order-to-order transition revealed that the rate determining step is the unfolding process of alpha-helix to random coil. Previously, we have reported the conformational change of poly(L-lysine) induced by DLPA vesicles at neutral pH, where the beta-structure transition from random coil was observed. Thus two types of transition of poly(L-lysine) are observed depending on bulk pH, i.e., from random coil to beta-structure and from alpha-helix to beta-structure. So far the phospholipid-induced conformations of poly(L-lysine) were interpreted in terms of counterbalance between the positively charged terminals of the lysyl chains and the negative headgroups of the phospholipid in vesicle. However, present work indicates the direct interaction other than electrostatic interaction between the lysyl chain and phosphate groups of the lipid.

Circular Dichroism↗
PubMed1994

Human papillomavirus type 16 DNA detected by the polymerase chain reaction in non-cancer tissues of the head and neck.

Cancer-free tissues from various anatomical subsites in the head and neck were examined by the polymerase chain reaction (PCR) for the incidence of human papillomavirus (HPV) types 16 and 18. We detected HPV-16 DNA in 9 of 103 samples (8.7%), including specimens from the paranasal sinuses, tonsil, hypopharynx and larynx. However, no HPV-16/18 DNA was detected by Southern hybridization in these 9 samples. The significance of the presence of HPV-16 DNA in non-cancer tissues is still unknown, but PCR detection only of high-risk HPV DNA in head and neck cancer should be evaluated cautiously because of its ubiquity in this region.

Adolescent↗
PubMed1994

An immunohistochemical study of the distribution of blood group substances and related antigens in primary colorectal carcinomas and metastatic lymph node and liver lesions, using monoclonal antibodies against A, B, H type 2, Le(a), and Le(x) antigens.

Using indirect immunoperoxidase staining, we examined the distribution of blood group substances and related antigens, including Le(a), A, B, H type 2, and Le(x), in 87 carcinomas and 42 normal mucosal specimens of colon and rectum, as well as in metastatic lesions of 32 lymph nodes and 9 liver specimens. The compatible expression rate of A/B/H type 2 antigens was 33.3% (3/9) in proximal normal colon, but only 6.1% (2/33) in distal normal colon. Compatible expression was observed in 14 of 25 carcinomas in the proximal colon (56.0%), but these antigens in distal colon cancers reappeared with a high positive rate, 62.9% (39/62). The rate of H type 2 accumulation with the deletion of A and/or B antigens was 6.9% (6/87). Incompatible expression was not observed in colorectal cancer. Le(a) and Le(x) antigens were expressed in normal mucosa and primary carcinoma throughout the colon. Le(a) and Le(x) in primary carcinoma that showed A/B deletion with/without H type 2 accumulation was expressed more than in carcinoma with A/B/H type 2 compatible expression (88.2% vs 71.7% for Le(a); 94.1% vs 88.7% for Le(x), respectively). In 16 of 32 patients (50.0%), A/B/H type 2 antigen expression in metastatic lesions had disappeared or was decreased compared with that in primary carcinoma, followed by metastasis to regional lymph nodes. These results suggested that: (a) A/B/H type 2 blood group substances in the distal colon behave as tumor-associated antigens in colorectal carcinoma. (b) Most frequently, A/B/H type 2 antigens expressed in primary carcinoma were weakened or had disappeared in metastatic lymph nodes. Further investigation of the biological function of carbohydrate chains, such as those of blood group substances and related antigens on cancer cell surfaces may lead to a solution of the problem of the metastatic behavior of tumor cells.

Adenocarcinoma↗
PubMed1994

An immunohistochemical employer monoclonal antibodies against Le(a), sialyl Le(a), Le(x), and sialyl Le(x) antigens in primary colorectal, carcinomas and lymph node and hepatic lesions.

The immunohistochemical expression of sialylated and non-sialylated forms of both Le(x) and Le(a) were studied in 87 carcinomas and 42 normal mucosal specimens of colon and rectum, as well as in 32 metastatic lymph nodes and 9 hepatic lesions, using an indirect immunoperoxidase staining. Their antigens were expressed in normal mucosa with the following frequencies: Le(a), 95.2% (40/42); sialyl Le(a), 88.1% (37/42); Le(x), 95.2% (40/42); and sialyl Le(x), 17.0% (7/42), whereas in carcinomas, the respective rate of frequency were: 78.2% (68/87); 78.2% (68/87); 90.8% (79/87); and 93.1% (81/87). Sialyl Le(x) antigen showed the highest tumor specificity compared to other antigens. In three normal mucosal specimens and four carcinomas with Le(a-b-) phenotype, the expression of type 1 antigens (Le(a) and sialyl Le(a)) was not consistent, whereas type 2 antigens (Le(x) and sialyl Le(x)) were consistently observed in carcinomas. The staining of type 1 antigens and Le(x) was decreased in metastatic lesions compared with primary carcinomas, whereas sialyl Le(x) antigen had the same positive-staining rate in both. Metastatic carcinoma expressed the sialylated form more predominantly than the non-sialylated form in type 2 antigens whereas the opposite result was observed in type 1 antigens. These results suggested that: (a) sialyl Le(x), defined by monoclonal antibody CSLEX1, may be useful as a tumor-associated antigen in colorectal carcinoma, and (b) the alteration of Lewis-related carbohydrate antigens in cancer cell membranes, including sialylation and/or aberrant glycosylation, may be related to metastatic behavior.

Adenocarcinoma↗
PubMed1994

Effects of chemical deactivation of the interstitial nucleus of Cajal on the vertical vestibulo-collic reflex induced by pitch rotation in alert cats.

The basic circuitry for the vestibulo-collic reflex (VCR) is a three-neuron arc, and this reflex requires the temporal and spatial transformation of vestibular signals to activate the appropriate neck muscles. Signals carried by vestibulo-collic neurons are insufficient to explain the responses of neck muscles. However, it is still unknown as to where the additional signal conversion is performed in the vertical VCR. We examined the effects of chemical deactivation of the interstitial nucleus of Cajal (INC) on the responses of biventer cervicis EMG induced by pitch rotation in the dark in alert head-fixed cats, and compared the results with the vertical vestibulo-ocular reflex (VOR) and also with the VCR and VOR induced by horizontal rotation. Muscimol infusion into the bilateral INC resulted in phase advance and gain drop in both the vertical VCR and the VOR, although the change was smaller in the VCR. The response phases of the horizontal VCR and VOR were not affected. Muscimol infusion outside the INC did not affect the phase of the vertical VCR or VOR. These results suggest that the INC is partially involved in temporal conversion of vestibular signals in the vertical VCR as well as in the VOR evoked by pitch rotation in alert cats.

Animals↗
PubMed1994

Serum 7 alpha-hydroxycholesterol reflects hepatic bile acid synthesis in patients with obstructive jaundice after external biliary drainage.

To examine the hypothesis that serum levels of 7 alpha-hydroxycholesterol reflect bile acid synthesis in the liver, we analyzed serum 7 alpha-hydroxycholesterol and bile acid output in 13 patients with obstructive jaundice after relief of biliary obstruction. Before biliary drainage, the serum level of 7 alpha-hydroxycholesterol was 92 +/- 12 pmol/ml (mean +/- S.E.M.) and was significantly lower than the control value (226 +/- 26 pmol/ml, p < 0.01). After biliary drainage, serum 7 alpha-hydroxycholesterol level and biliary bile acid outputs began to rise in some patients, indicating reversible liver dysfunction. In other patients, serum 7 alpha-hydroxycholesterol levels and bile acid outputs did not increase, suggesting severe or irreversible liver dysfunction. On and after the third day of biliary decompression, serum 7 alpha-hydroxycholesterol levels correlated well with bile acid excretion (p < 0.01, r = 0.93). Other liver function parameters, such as serum bilirubin, serum bile acids, albumin, and bile flow, also revealed significant correlation with serum 7 alpha-hydroxycholesterol levels. We conclude that the serum 7 alpha-hydroxycholesterol level clearly reflects bile acid synthesis in the liver and that it may serve as a useful parameter for the assessment of hepatic functional recovery in patients with obstructive jaundice after biliary drainage.

Aged↗
PubMed1994

Effects of sevoflurane, isoflurane, enflurane, and halothane on left ventricular diastolic performance in dogs.

The effects of volatile anesthetics on active (ventricular relaxation) and passive (chamber stiffness) indices of diastolic function and on left ventricular filling rates in dogs were studied to determine how these agents affect left ventricular diastolic performance. Thirty-five mongrel dogs were randomly assigned to receive sevoflurane, isoflurane, enflurane, or halothane. Left ventricular pressure waveforms, phonocardiograms, and echocardiograms were recorded after administering the anesthetics at concentrations of 0% (control), 1%, 2%, and 3%. Ventricular relaxation was defined as the time constant of the decline in left ventricular pressure. Chamber stiffness was derived from the ventricular pressure-volume relationship during passive filling. Rapid filling rate, slow filling rate, and atrial filling rate were obtained from echocardiograms and phonocardiograms. No change in the time constant or in chamber stiffness was observed at any concentration of sevoflurane or isoflurane. However, the highest studied concentration of enflurane and halothane produced a significant increase in the time constant and in chamber stiffness. Rapid filling rate as well as atrial filling rate decreased significantly with the volatile anesthetics, especially with enflurane and halothane. Sevoflurane and isoflurane did not alter ventricular relaxation or chamber stiffness, but did affect diastolic function as manifested by their alteration of filling rates. In contrast, enflurane and halothane each prolonged ventricular relaxation and increased chamber stiffness. With the administration of the volatile anesthetics, the rapid filling rate decreased with the deterioration of diastolic function; in addition, atrial filling rates decreased and did not compensate for the reduction in early ventricular filling.

Anesthetics, Inhalation↗
PubMed1994

Effects of nicardipine, nitroglycerin, and nitroprusside on left ventricular diastolic function during enflurane anesthesia.

The purpose of this study was to evaluate the effects of nicardipine (NCR), nitroglycerin (NTG), or nitroprusside (SNP) on left ventricular diastolic function during enflurane anesthesia in acutely instrumented dogs. Using echocardiography, time constants for the decline in isovolumic left ventricular pressure (T), stiffness constant (K), diastolic time intervals, and left ventricular filling rates were measured in 21 mongrel dogs during the following conditions: (1) 0% enflurane (control), (2) 3.3% enflurane, (3) intravenous infusion of NCR, 1 microgram/kg/min, NTG, 2 micrograms/kg/min, or SNP, 2 micrograms/kg/min, during 3.3% enflurane, and (4) intravenous infusion of NCR, 2 micrograms/kg/min, NTG, 4 micrograms/kg/min, or SNP, 4 micrograms/kg/min, during 3.3% enflurane. During 3.3% enflurane anesthesia, T and K increased significantly, and left ventricular filling rates decreased. The administration of NCR, NTG, or SNP returned T and K to control levels. Left ventricular rapid filling rate returned toward the control level only with NCR (P < 0.05, NCR v NTG, SNP). It is concluded that the depression of diastolic function during enflurane anesthesia was improved by NCR or other vasodilators. The extent and mechanism of action of these vasodilators might differ, however.

Anesthesia, Inhalation↗
PubMed1994

Increased expression of mineralocorticoid receptor in human ileum after total colectomy: immunohistochemical and immunoblotting studies.

Aldosterone is known to regulate transmembrane ion transport and water absorption through its binding to mineralocorticoid receptor (MR) in the mammalian colon. A possible roles of aldosterone has been suggested in increased water absorption from remnant ileum in the patients with total colectomy. We, therefore, studied immunolocalization of MR in remnant ileal mucosa in the patients with total colectomy in order to study the role of aldosterone in water and sodium absorption in these patients. Immunohistochemical localization of MR was performed in ileal mucosa of 7 patients with total colectomy and 5 cases of normal ileum obtained from the resection of ascending colon due to carcinoma by using a polyclonal antibody raised against a mineralocorticoid receptor fusion protein as a primary antibody and a biotinstreptavidin system for immunostaining. Immunoblotting was also performed. Positive MR immunoreactivity was observed in both cytoplasm and nucleus of absorptive cells of ileum of total colectomy patients but not in control normal ileum. Immunoblotting revealed the presence of an approximately 100 kDa immunoreactive product corresponding to mineralocorticoid receptor. Aldosterone is considered to act on ileal mucosa following total colectomy and the aldosterone dependent sodium transport and water absorption may be accelerated in ileal mucosa after total colectomy, which is consistent with the postoperative decrease in the stool volume observed in these patients. In conclusion, increased expression of the mineralocorticoid receptor in remnant ileum may play an important role in intestinal adaptation in total colectomized patients.

Adenomatous Polyposis Coli↗
PubMed1994

Management of acute leukemia during pregnancy: from the results of a nationwide questionnaire survey and literature survey.

In March, 1993, a questionnaire was sent to 362 gynecological and obstetric offices of national, prefectural and municipal hospitals and private university hospitals with 250 beds or more. Answers were collected from 260 institutions. Thus, this study analyzed 39 patients with acute leukemia during pregnancy collected by the questionnaires survey and 64 cases reported in the Japanese literatures during 1975-1993 (total 103 patients). The weeks of pregnancy were defined as the 1st (< 15th week), 2nd (16th-27th week), and 3rd (> 28th week) trimesters. The time of diagnosis of leukemia during pregnancy changed from 25% in the 2nd trimester and 62% in the 3rd trimester during 1975-1984 to 39% and 48% after 1985, respectively. After 1985, the remission rate was 72% in the questionnaire group and 75% in the group from literatures. There was no statistical difference. The 50% survival period was 12 months in the group during 1975-1984, but 25 months in the group after 1985. The survival was significantly longer in the patients whose induction therapy was started before delivery than in those treated after delivery. The results suggest that the treatment for acute leukemia during pregnancy should be initiated as soon as possible after the diagnosis of leukemia, with carefully selected regimens. It is important that the time of delivery should be selected considering the maternal and fetal conditions after consultation with an obstetrician.

Adult↗