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Biomedical subjects

A Fukui

Publications and source records attributed to A Fukui.

At least 109 records · Page 6Linked to original sources

PC-766B, a new macrolide antibiotic produced by Nocardia brasiliensis. I. Taxonomy, fermentation and biological activity.

An actinomycete strain SC-4710, a new soil isolate, was found to produce a new macrolide antibiotic, PC-766B. Chemotaxonomic analysis of the producing organism revealed that the cells of SC-4710 had type IV cell wall, type A whole cell sugar pattern, type PII phospholipids, menaquinone MK-8(H4), cellular fatty acids comprising straight-chain saturated, unsaturated and tuberculostearic acids, and mycolic acids. The strain was identified as Nocardia brasiliensis (Lindenberg) Pinoy. The antibiotic, PC-766B, was active against Gram-positive bacteria, and some fungi and yeasts, but inactive against Gram-negative bacteria. It also showed antitumor activity against murine tumor cells in vitro and in vivo, and a weak inhibitory activity against Na+, K(+)-ATPase in vitro.

Animals↗

Extracorporeal circulation for tissue transplantation (in the case of venous flaps).

During free-tissue transplantation, recipient vessels are often crushed as a result of trauma or radiation therapy, making anastomosis of vessels difficult. In some cases, a second operation is unavoidable because of formation of a postoperative thrombus at sites of the anastomosis. To solve such problems, it should be possible to transplant tissue anywhere in the body without vascular anastomosis by extracorporeal circulation. This study mainly concerned venous flaps that were spindle-shaped and 4 x 3 cm in size. One hundred and forty-six male Japanese White rabbits, weighing 2.0 to 2.5 kg, were used. Stabilized hemoglobin, lactated Ringer's solution, whole blood, and plasma were used as perfusate. Each of these perfusates was injected at a rate of 5 ml per hour continuously for 3 days in good recipient sites and for 7 days in poor recipient sites. Five rabbits were used in each group. The flaps were examined histologically and electron microscopically. Moreover, in the plasma group, microangiography was performed to observe blood circulation between the flap and the surrounding tissue. The flaps survived in all cases in which the plasma group had good recipient beds but did not survive in any of the other cases, in which degeneration of the endothelial cells was detected prior to edema. According to the results of this examination, tissue viability of the venous flap could be maintained for at least 3 days by perfusion of plasma. During this time, in the cases of good recipient sites, blood may begin to recirculate between the flap and the surrounding tissue.

Angiography↗

[A case of stunned myocardium with marked 99mTc-PYP accumulation].

A 71-year-old woman with unstable angina was admitted to our department. Upon admission, electrocardiography revealed a QS pattern in Leads V1-V3. Left ventriculography disclosed akinesis of the anterior wall and the septum. Myocardial scintigraphy with 99mTc-pyrophosphate (PYP) revealed marked accumulation (Parkey's grade III) in the anterior wall, septum and apical region. Coronary arteriography revealed stenosis (99% with delay) in the LAD #6. Based on these findings, we performed percutaneous transluminal coronary angioplasty (PTCA) on this patient. About 3 months later, the patient underwent PTCA again because stenosis had recurred. The resting 201Tl myocardial scintigram, taken immediately after the first PTCA, demonstrated complete defects in the anterior wall, septum and apical region. After the second PTCA, no stenosis was observed. About 1 year later, the wall motion returned to normal (except in part of the apical region), suggesting that this was a case of stunned myocardium. On the same occasion, the 201Tl uptake was normal except in the apical region. The present case was regarded as stunned myocardium which demonstrated marked radioactivity accumulation when examined by 99mTc-PYP myocardial scintigraphy. In the past, 99mTc-PYP has been thought to be incorporated into irreversibly impaired myocardium (e.g., in cases of acute myocardial infarction). The uptake of 99mTc-PYP into stunned myocardium has not been reported before. Thus, this case is rare and noteworthy.

Aged↗

[Clinical application of 31P MRS to malignant liver tumors--with an emphasis on evaluation of response to therapy].

Malignant liver tumors in 19 cases (13 hepatomas and 6 metastatic tumors) were studied by 31P magnetic resonance (MR) spectroscopy. Five healthy volunteers were also studied. Volume localization was performed using the ISIS sequence. Compared with normal liver, the MR spectra of malignant tumors showed an elevated phosphomonoester (PME) peak relative to beta ATP (p less than 0.005), and tumors were slightly alkaline (pH 7.32 +/- 0.08) before therapy. Nine cases of hepatomas responding to chemoembolization showed extremely reduced signal intensity of spectra. Tumor pH was compared before and after therapy in four cases that showed good response to therapy, and was elevated in all of them. Three metastatic tumors with good response showed reductions in PME and ATP after therapy. MR spectroscopy with adequate localization technique is useful in demonstrating the response of malignant tumors to therapy.

Carcinoma, Hepatocellular↗

[Results of radiation therapy for squamous cell carcinoma of the uterine cervix using high dose-rate intracavitary irradiation].

We retrospectively analyzed 216 previously untreated patients with cervical cancer treated by high dose-rate intracavitary irradiation between 1978 and 1986. Cumulative 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 72.3%, 88.9%, 68.9%, 75.0%, 64.0% and 16.7%, respectively. Cause-specific 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 93.3%, 88.9%, 74.7%, 75.0%, 68.9%, and 18.8%, respectively. Recurrences outside the pelvis in stage IIb and IIIb (14.9% and 24.0%) were more common than loco-regional recurrences (10.3% and 12.0%). However, loco-regional recurrences (50%) were most frequent in stage IVa. Thirteen patients (6.0%) required surgical management for intestinal complications (severe). Six patients (2.7%) died due to intestinal complications (fatal). These fatal and severe complications were closely correlated with the dose of external radiation. These data suggest that intracavitary irradiation using a high dose-rate system is useful for the treatment of uterine cancer; however, further efforts to reduce intestinal complications by lowering the dose of external radiation will be necessary. It is also suggested that a combined modality, such as chemotherapy, is necessary for controlling metastases outside the pelvis in stage IIb and IIIb, and for local control in stage IVa.

Adult↗

[Signal contamination problem in three-dimensional localization technique of MR spectroscopy--experiment and an analysis of patient data].

Signal contamination from the surrounding volume was studied using the ISIS sequence, a three-dimensional localization technique. In phantom experiments, contamination decreased with the increase of Tr, regardless of where the contamination originated from. In 52 localized liver spectra with a Tr of 2 sec, PCr contamination was estimated at 3 to 4%, and contamination of ATP signals from the surrounding liver tissue at less than 1%, because of the relatively short T1 of ATP in the liver. In the spectra of brain neoplasms obtained using the simultaneous double-volume selection technique, the PCr ratio in the tumor relative to the control area was high in low grade astrocytoma (0.80, n =8) and low in others (0.45, n = 11). Considering contamination and spectral noise, a PCr ratio of less than 0.4 does not strongly suggest the existence of PCr in tumors. Among 25 cases whose therapeutic processes were monitored by MRS, signal disappearance was observed in two cases in the localized spectra after therapy. In both of them, tumor necrosis was proved pathologically and correlated well with spectroscopic findings. It was found that the ISIS technique suppressed signal contamination to the level of several percents, providing spectra of acceptable quality through localization.

Humans↗

A new cell line (XTY) from a tumor of Xenopus laevis.

A new cell line (XTY) was derived from a tumor of a female Xenopus laevis. This cell line has been proliferating in standard amphibian culture medium for more than 4 years (470 generations) and has a doubling time of 75.5 h at 25 degrees C. The cells aggregate into large groups, and their stellate morphology and the expression of desmin demonstrated by immunocytochemistry suggest that their origin is not epithelial.

Animals↗

Continuous local intraarterial infusion after prolonged arterial stasis in the fingers and toes.

Seven patients with trauma to eight digits and one toe went untreated for arterial stasis, with subsequent development of posttraumatic changes in skin coloration. In two patients involving two digits, a daily dose of 2,000 ml containing 240,000 U urokinase, 80 micrograms prostaglandin E1, and 10,000 U heparin in lactated Ringer's solution was administered by intravenous infusion for 10 consecutive days; one of the two digits became necrotic. In all subsequent patients, a daily dose of 80 ml containing 240,000 U urokinase, 40 micrograms prostaglandin E1, 10,000 U (maximum) heparin, and low-molecular-weight dextran was administered by continuous local intraarterial infusion for 10 consecutive days. These seven extremities survived, even in the case of two digits and one toe with over 50 hr of arterial stasis. We believe that revascularization of extremities following prolonged periods of arterial stasis may be possible by means of continuous local intraarterial infusion of antithrombotic agents.

Aged↗

An experimental study of the flow-through venous flap: investigation of the width and area of survival with one flow-through vein preserved.

A quantitative analysis was undertaken to investigate the width and area of survival of flow-through venous flaps in 20 ears of 10 rabbits. The 3.0- x 3.0-cm flap models, which included one flow-through vein, were prepared with additional circulation from the graft bed and surrounding tissue excluded, as far as possible. The flaps were divided as follows: Group A--composite grafts (n = 10), and Group B--flow-through venous flaps (n = 10). All flaps in Group A became necrotic and all those in Group B showed partial survival along the flow-through vein. The average survival width was 1.10 +/- 0.48 cm, and the survival rate was 44 +/- 19.3 percent. Microangiograms revealed patency of the flow-through vein in all flaps of Group B. Histologically, there tended to be progressively more fibrous tissue in the area further away from the flow-through vein. The model is useful to investigate the width and area of survival in flow-through venous flaps.

Angiography↗

Proof of plasmatic imbibition in rat musculocutaneous grafts: enzymatic proof using peroxidase.

At present, the concept of plasmatic imbibition is generally accepted. That is, observation of weight change or pigmentation methods of the grafts were established to support it. In the present study, we investigated plasmatic imbibition in rat musculocutaneous grafts histologically using peroxidase, which is one of the reductases. Tissue pigmentation by peroxidase became an insoluble sediment that indicated the sites of peroxidase activity. The entire contact surface of the graft with the recipient bed was stained brown within a few minutes after the operation. At 30 minutes, the panniculus carnosus and dermis were stained dark brown diffusely, extending toward the epidermis. This condition continued until the sixth day at least. As a result, peroxidase that was dissolved with the exudate between the graft and recipient bed was imbibed into the musculocutaneous graft.

Absorption↗

[Left ventricular diastolic function in apical hypertrophic cardiomyopathy].

To investigate left ventricular (LV) diastolic function in patients with apical hypertrophic cardiomyopathy (AHCM), we analyzed the LV cineangiograms (RAO 30 degrees) and pressures (tip manometer) in 11 patients with AHCM who had giant negative T waves on their electrocardiograms and "ace of spades" configurations on the LV angiograms. Ten patients with non-obstructive HCM (HNCM) and 10 normal subjects served as controls. LV volumes and instantaneous rates of LV volume changes were derived from frame-by-frame analyses of their LV angiograms. LV isovolumic relaxation was assessed according to the time constant (T) of LV pressure decay. LV diastolic distensibility was evaluated by plotting diastolic pressure-volume curves. There was no significant change in the LV systolic functions among these 3 groups. Compared with normals, LV end-diastolic pressure was equally elevated in AHCM and HNCM. The T of isovolumic pressure decay was significantly prolonged in AHCM and HNCM. LV early diastolic filling was maintained at the normal level in AHCM as assessed by the peak filling rate (PFR) during the rapid filling period and the time from end-systole to PFR. The LV diastolic pressure-volume relation shifted upwards in both AHCM and HNCM. In conclusion, impaired LV isovolumic relaxation and decreased diastolic distensibility, which are associated with HNCM, may also be present in AHCM.

Adult↗

[The effect of heart rate on the time constant of isovolumic relaxation of the left ventricle].

A time constant (T) of the left ventricular isovolumic relaxation, which expresses the relaxation rate of the left ventricle, may be affected by change of the heart rate. There are few clinical reports concerning the relationship between T and heart rate. We studied the relationship between T and heart rate in 10 patients with normal coronary arteries and left ventricular function. Left ventricular pressure was measured using a catheter-tip manometer during right atrial pacing, which was performed at the rate of 10, 20, 40 beats/min in addition to the baseline rate, and finished at 140 or 150 beats/min. Two measurements were made for T.1) Tw from the slope of In (pressure) against time, and 2) Tb by exponential analysis which also estimated the asymptote. As the heart rate increased, both Tw and Tb gradually shortened (Tw: from 38.5 +/- 4.9 msec at the control heart rate to 28.9 +/- 5.6 msec at 140 or 150 beats/min; Tb: from 54.7 +/- 11.4 msec at the control heart rate to 34.9 +/- 5.7 msec at 140 or 150 beats/min). These findings suggest that left ventricular isovolumic relaxation is strongly affected by change of the heart rate in man.

Adult↗

[Coronary artery disease in diabetic patients].

Although it is well known that diabetics have high mortality rates due to ischemic heart disease (IHD), controversies still exist about the severity of coronary artery disease in diabetics compared to nondiabetics. We compared coronary arteriographies of 50 diabetics with IHD to those of 50 nondiabetics with IHD. In regard to coronary risk factors, incidence of obesity was significantly higher in diabetics. Incidence of hypertension, hypercholesteremia, hyperuricemia was higher, although not significant, in diabetics. Incidence of smoking was significantly higher in nondiabetics. The diabetic group showed a significantly higher incidence of patients with more than two or three diseased vessels, and a significantly higher number of diseased coronaries with more than 50% stenosis per patient compared to nondiabetics (5.6 +/- 3.7 vs 3.7 +/- 3.2). The distribution of diseased coronaries with more than 75% stenosis showed no difference between diabetics and nondiabetics. The incidence of coronary spasm was significantly lower in diabetics (12% vs 28%). The high incidence of multiple vessel disease in diabetics was thought to be due to other complicated coronary risk factors, especially hypertension and hypercholesteremia.

Aged↗

Continuous local intra-arterial infusion of antithrombotic agents for replantation (comparison with intravenous infusion).

The success rate of replantation of amputated digits and limbs appears to be improved by local continuous intra-arterial infusion of urokinases, heparin and PGE1 at a daily dose of 240,000 I.U., 10,000 U, and 40 micrograms, respectively, for ten days, in comparison to intravenous infusion of the drugs. The purpose of this study was to investigate the difference between the haematological effects of intra-arterial and intravenous infusion. Accordingly coagulation and fibrinolytic enzyme levels were examined before, and at 4 and 12 hours after the start of infusion and on the 3rd and 10th postoperative days. Intra-arterial infusion was advantageous over intravenous infusion probably because the effect of general metabolism on drug levels was small, drugs exhibited immediate action and efficacy was localised. No particular side effects were demonstrated.

Blood Coagulation Factors↗

The sliding venous flap for covering skin defects with poor blood supply on the lateral aspects of fingers.

For the treatment of skin defects with poor blood supply on the lateral aspects of the fingers, particularly the radial side of the index finger and the ulnar side of the little finger which have been difficult to cover conventionally, we have developed the sliding venous flap. The flap can be moved by using the "sag" obtained from the dissected dorsal veins of the same finger. We have applied this technique in six cases with excellent results. The indications are limited to cases with only slight crushing of the dorsum of the finger. We consider this technique safe and effective in covering skin defects with poor blood supply on the lateral aspects of fingers.

Adolescent↗

An investigation of venous pressure and oxygen tension in human extremities: an experimental study of survival in pedicled venous flaps.

The pedicled venous flap is used at various sites, such as the finger, forearm, and leg. The authors previously reported that the reasons for the viability of such flaps, based on the digital dorsal vein and used for repairing digital skin defects in the earlier study, were high venous pressure or oxygen tension, as well as the possible effects of plasmatic imbibition and outflow through the draining vein. To investigate the importance of venous pressure and oxygen tension in the survival of these flaps at other sites in the body, measurements were made comparing these parameters in the digital vein, cephalic vein, and greater saphenous vein, which are all used clinically as draining veins in pedicled venous flaps. Although measurements in other sites were consistently lower than in the digital dorsal vein, since these other venous flaps are nevertheless viable in the clinical situation, their viability may not be due only to relatively high venous pressure and oxygen tension. The authors intend to carry out further comparative studies on plasmatic imbibition in the flap and outflow through the draining vein.

Adolescent↗

Combined therapy with antithrombotic agents and radical scavengers for reperfusion injury of flaps.

The usefulness of combining antithrombotic agents and radical scavengers in the treatment of reperfusion injury (an almost ideal approach) was substantiated using an ischemic flap model. The cause(s) of reperfusion injury was hypothesized on the basis of differences in effects between antithrombotic agents and radical scavengers in the experimental groups. Flap specimens were also obtained regularly for histologic examination. The experiment was conducted in nine rabbit groups. For continuous treatment with intraarterial antithrombotic agents, both heparin and urokinase were continuously injected at respective administration rates of 20 U/kg/hr and 200 IU/kg/hr for seven consecutive days immediately before reperfusion. For intraarterial radical scavenger treatment, a solution of both 30,000 U/kg SOD and 30,000 U/kg catalase in 5 ml of a lactated Ringer's solution was injected over a period of about 30 min immediately before reperfusion. The ischemic time of the flaps was 10 hr for Group I and 12 hr for Group II. Each group was comprised of subgroups a, b, c, and d: a = control; b = continuous intraarterial antithrombotic agent injection; c = intraarterial lactated Ringer's solution alone; and d = intraarterial radical scavenger injection. For Group II, an additional subgroup e was established, which received continuous injection of both intraarterial antithrombotic agents and injected intraarterial radical scavenger. In the 10-hr ischemic treatment group, an effect was obtained by continuous intraarterial antithrombotic agents alone. In the 12-hr ischemic treatment group, a significant improvement in flap-take ratio was obtained using intraarterial radical scavenger, in combination with antithrombotic agents. Observation of the flaps that survived in subgroups Ib and IIe revealed skin thinning, vascular wall thickening, and muscular tissue degeneration, although the skin architecture was well preserved.

Animals↗