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Biomedical subjects

K Ohishi

Publications and source records attributed to K Ohishi.

At least 181 records · Page 10Linked to original sources

The internal thoracic artery and its branches after coronary artery anastomoses in pediatric patients.

The internal thoracic artery has been favored because of its superior early and late patency for coronary artery bypass grafting (CABG) in pediatric patients. We have studied the angiographic changes of the internal thoracic artery and its side branches before and after CABG with internal thoracic artery to the left anterior descending artery. The internal thoracic artery with remaining thymic or pericardial branches was patent but showed enlargement of the branches in the early period after the operation, and a postoperative exercise test suggested a remaining ischemic lesion in the bypass. Angiogram taken 1 year after CABG demonstrated the grown internal thoracic artery with disappearance of most of the side branches, which had been enlarged 1 month after the operation. Our findings suggest the importance of ligation of the whole proximal internal thoracic artery branches to maintain good early and late patency.

Child↗

[Clinical and epidemiological aspects of enteritis due to Salmonella hadar. I. Isolation of S. hadar from sporadic diarrhea--clinical and bacteriological study].

Before 1983, S. hadar was seldom isolated from man, animals, food or the environment in Japan: only one strain having been isolated from man and one from the environment. In subsequent years there has been a progressive increase in the number of isolations. S. hadar is now one of the commonest serotypes isolated from cases of sporadic diarrhea in Shizuoka Prefecture (Table 1). However, the epidemiology of S. hadar is not clearly understood. Reports on the clinical features of S. hadar gastroenteritis are also scarce. We examined the clinical symptoms of 15 cases of S. hadar gastroenteritis. S. hadar was encountered in patients of all ages. Infants and young children below 10 years of age constituted 47% of all cases. Seventy per cent of young children below 10 years of age experienced fever of more than 39 degrees C. This incidence was significantly higher than that of general Salmonella gastroenteritis observed in our previous study, in which fever of more than 38 degrees C was noted in 61% of the children. We found one case of presumptive person-to-person spread. No other household contacts of index patients suffered from diarrhea during the same period. Systematic examination for Salmonella contamination was performed for poultry farms, broiler chickens, broiler processing plants and meat on the market. 259 Salmonella strains were isolated from 1197 samples. S. hadar accounted for 37.1% (96) of all isolations (259). A drug resistance test was performed for 51 strains of the diarrhea cases and 67 strains of the environment. The pattern of the distribution of MICs of 9 drugs was similar in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Clinical and epidemiological aspects of enteritis due to Salmonella hadar. II. Environmental contamination by Salmonella hadar in Shizuoka Prefecture--studies on the feasibility of reducing S. hadar infection].

A systematic examination was performed for environmental food contamination by Salmonella in poultry farms, broiler chickens, broiler processing plants and meat on the market. Salmonella was isolated from 219 of 1197 samples and the serotypes showed a wide distribution. (Table 1-1). S. hadar accounted for 37.1% (96) of all isolations (259). The contamination rate of broiler chickens on arrival at broiler processing plants is relatively low. However, in the broiler processing plants, containers, processing machinery, cooling water and slaughters were highly contaminated by Salmonella, S. hadar being the most prominent serotype in the plants. 64% of chicken meat on the market was contaminated by Salmonella, S. hadar being the second most prominent serotype. 11% of the pork and none of the beef or horseflesh was contaminated by Salmonella. These results indicate that poultry is the main source of S. hadar infection in humans. However, no S. hadar was isolated from cultures of 119 samples of feed for chickens from each delivery (Table 1-1). Thus, as the main source of infection by S. hadar of broiler chickens, an association with the feed seems to be ruled out. S. hadar was isolated at three of 18 poultry farms within Shizuoka Prefecture. Follow-up studies were performed at the three poultry farms which revealed that in two of them, Salmonella was completely eradicated on completion of disinfection. In the other one farm, which is still being disinfected, various strains of Salmonella including S. hadar still survived. We conclude that the main cause of the problem is the magnification of contamination of Salmonella-free material during the process at the broiler processing plants.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Effects of ATP on pre- and postglomerular juxtamedullary microvasculature.

Based on evidence that extracellular ATP can influence vascular smooth muscle function in other organ systems, experiments were conducted to characterize the responsiveness of rat juxtamedullary microvascular segments to ATP. Experiments were performed using the in vitro blood-perfused juxtamedullary nephron preparation combined with video microscopy. Pentobarbital-anesthetized rats were pretreated with enalaprilat (2 mg iv) for 30 min before the right kidney was isolated and prepared for study. Renal perfusion pressure was set at 110 mmHg and held constant. Under control conditions, afferent and efferent arteriolar diameters averaged 19.9 +/- 1.4 (n = 19) and 21.6 +/- 1.2 microns (n = 10), respectively. Superfusion with 1, 10, and 100 microM ATP solutions induced sustained dose-dependent afferent vasoconstriction of 8.3 +/- 1.4, 12.8 +/- 1.7, and 12.1 +/- 2.1%, respectively (P < 0.01). Afferent vasoconstrictor responses to ATP were also observed during adenosine receptor blockade. In contrast, efferent arterioles were unresponsive to ATP stimulation even at concentrations as high as 100 microM (P > 0.05). Arcuate and interlobular arterial diameters averaged 82.0 +/- 15.7 (n = 5) and 43.4 +/- 4.5 microns (n = 6), respectively, during control conditions and responded to ATP treatment with a transient vasoconstriction followed by a gradual return to control diameter. Interlobular arteries exhibited a sustained constriction only at the 100 microM concentration (P < 0.05). These data demonstrate that afferent arterioles are more responsive to ATP treatment than other renal microvascular segments and suggest the presence of ATP-sensitive P2x purinoceptors on pre- but not postglomerular juxtamedullary microvascular elements.

Adenosine↗

EDRF-angiotensin II interactions in rat juxtamedullary afferent and efferent arterioles.

The in vitro blood-perfused juxtamedullary nephron technique was utilized to determine the contribution of endothelium-derived relaxing factor (EDRF) to resting renal arteriolar caliber and to evaluate the interaction between EDRF and angiotensin II (ANG II) in renal microvascular control. Video microscopy was employed to visualize rat afferent and efferent arterioles and to measure their responses to blockade of nitric oxide (NO), which has been shown to account for much of the biological action of EDRF. The NO synthesis inhibitor, N omega-nitro-L-arginine (L-NNA), elicited vasoconstriction in a concentration-dependent manner, with 1,000 microM L-NNA significantly reducing both afferent (16 +/- 3%) and efferent (13 +/- 1%) diameters. This concentration of L-NNA also blocked the vasodilator response to 10 microM acetylcholine, while responsiveness to sodium nitroprusside was maintained. Vasoconstrictor responses to 1,000 microM L-NNA were attenuated in kidneys from rats pretreated with enalaprilat or losartan, reducing afferent diameter by 7 +/- 1 (n = 8) and 3 +/- 1% (n = 10) of control, respectively. Efferent arteriolar responses to L-NNA were similarly attenuated by losartan. The constrictor response to 10 nM ANG II was not exaggerated by L-NNA, suggesting that ANG II does not stimulate EDRF synthesis. These observations indicate that EDRF is continuously released in a quantity sufficient to affect both afferent and efferent arterioles of juxtamedullary nephrons in vitro. Furthermore, ANG II blockade attenuates the vasoconstriction elicited by L-NNA, suggesting that EDRF interacts with the renin-angiotensin system to control juxtamedullary afferent and efferent arteriolar resistance.

Acetylcholine↗

The role of 36 megadalton plasmid of Salmonella enteritidis for the pathogenesis in mice.

The pathogenesis associated with the 36 Megadalton (Md) plasmid of Salmonella choleraesuis subsp. choleraesuis serovar Enteritidis (S. Enteritidis) was assessed by using the plasmid-containing strain AL1190, plasmid-cured strain AL1192, and plasmid-reintroduced strain AL1193. After oral inoculation of strain AL1190 or AL1192 to C57BL/6 mice, mesenteric lymph nodes, spleens, and livers were examined for the numbers of viable bacteria and for the histopathological changes. The numbers of bacteria were greater and histopathological changes were severer in these organs of mice inoculated with strain AL1190, than in those with strain AL1192. Strains AL1190, AL1192, and AL1193 showed the equivalent survival rate to sera of guinea pig, calf, and pig, and grew equally well under the iron-limiting conditions. These results suggested that the 36 Md plasmid of S. Enteritidis contribute to the spread of the infection beyond small intestines to mesenteric lymph nodes, spleens, and livers, but not to serum resistance or acquisition of iron.

Animals↗

Modified De Vega's annuloplasty for functional tricuspid regurgitation--early and late results.

From 1978 through 1987, 321 patients who had functional tricuspid regurgitation (TR) associated with mitral or combined mitral and aortic valve disease underwent tricuspid annuloplasty with our modification of the original De Vega's annuloplasty technique. The modified De Vega's annuloplasty consisted of two separate semicircular sutures placed around the anterior and lateral aspect of the tricuspid valve. Preoperatively, 229 (71.3%) of the 321 patients were in New York Heart Association functional class III or IV. There were nineteen early deaths (5.9%), and 15 patients died during a follow-up period of 15 to 126 months (mean follow-up, 26 months). Five patients (1.5%) required reoperation because of biological mitral valve failure and recurrence of mitral stenosis. The severity of TR was evaluated by two-dimensional and pulsed Doppler echocardiography, and was classified on a scale of 0 to Grade 3 according to the maximal distance and the flow pattern of the regurgitant signals in the right atrium. Postoperative echocardiographic evaluation of TR was performed in 121 randomly selected patients late after operation. TR reduced to Grade 1 or less in 107 (88.4%) of the 121 patients after operation. Ninety-six percent of the survivors were in New York Heart Association functional class I or II, postoperatively. The actuarial survival rate for the 321 patients with the modified De Vega's annuloplasty including early deaths was 88.2% at 10 years and the actuarial rate of freedom from reoperation on the tricuspid valve was 97.6%. Our surgical experience indicated that the modified De Vega's annuloplasty, as the method of first choice, is a simple, reliable procedure and resulted in reduction of the severity of TR in 88.4% of the patients with functional TR.

Adult↗

[A device for hepatic arterial catheterization using saphenous vein graft].

We performed regional arterial infusion chemotherapy for hepatocellular carcinoma by retaining a hepatic arterial reservoir. The catheters were placed via gastroduodenal artery and positioned at the junction with common hepatic artery during operation. But we encountered many complications and did not perform regional arterial infusion chemotherapy. This time we cannulated through the saphenous vein graft by which hepatic perfusion was maintained by the superior mesenteric artery; we did not cannulate through the common femoral artery using a subcutaneously implanted reservoir. Venous arterial anastomosis is performed with interrupted (7-0 Prolene) vascular suture. Postoperative angiography by the reservoir showed total hepatic perfusion. There have been no instances of hemorrhage, thrombosis, or catheter dislodgement with this technique. Duration of follow-up varied from 2 to 7 months.

Carcinoma, Hepatocellular↗

[Clinical significance of posttetanic count (PTC) during onset and spontaneous offset of neuromuscular blockade induced by vecuronium].

To compare the clinical difference of posttetanic count (PTC) during onset and spontaneous offset, the changes of PTC during an intense neuromuscular blockade induced by vecuronium (0.08 mg.kg-1, i.v.) were measured using a neuromuscular transmission analyzer in 64 adult patients anesthetized with nitrous oxide and halothane. Furthermore, intubation score was evaluated when zero PTC was obtained. The obvious movement of diaphragm associated with endotracheal intubation was observed in 9 out of 20 patients (45%) even when it was performed after obtaining zero PTC. The difference of PTC responses between the onset and the offset was found. The difference was that, during the onset, a tetanic response was observed obviously and the height of the posttetanic single twitch was low, and during offset, even when no response was observed, the height of a posttetanic single twitch response was high with the same PTC. These facts indicate that the same PTC has different clinical significance during onset and offset.

Adult↗

Augmentation of interleukin-2 production after cardiac operations in patients treated with erythropoietin.

It has been reported recently that cardiac operations can be followed by a transient impairment of cell-mediated immunity. In this study we examined indices of cell-mediated immunity in patients undergoing cardiac operations. Twenty-five of the patients received erythropoietin (200 U/kg) daily for 2 weeks before and after operation, and 30 matched control patients did not receive erythropoietin. On postoperative day 1, the numbers of total T cells and helper/inducer T cells were significantly higher in erythropoietin-treated patients than in control patients. The ability of patients' cells to make interleukin-2 in vitro increased after erythropoietin injection in the preoperative period. By postoperative day 1, erythropoietin-treated patients exhibited a fall in interleukin-2 production that was significantly less than that in control patients; levels increased by day 2 to a mean value twice that of the preoperative baseline and more than four times the corresponding mean level in the control groups, and levels returned to the baseline range by postoperative day 14. Levels of interleukin-2 production in erythropoietin-treated patients were significantly higher than those in control patients at each interval tested through postoperative day 7. These findings indicate that erythropoietin treatment not only augmented levels of circulating erythrocytes but also improved indices of cell-mediated immunity. Although the mechanism responsible for this effect remains to be determined, the finding suggests that erythropoietin might help to ameliorate or prevent the impairment of immune function that can occur after cardiac operations.

Cardiac Surgical Procedures↗

Postoperative erythroderma after cardiac operations. The possible role of depressed cell-mediated immunity.

Erythroderma as a manifestation of graft-versus-host disease after cardiac operations with blood transfusion may occur more frequently in Japan than in other countries. We have seen this problem in five patients who, after heart operations, died with symptoms and signs characteristic of graft-versus-host disease: cutaneous eruption, fever, diarrhea, leukopenia associated with agranulocytosis, and liver dysfunction. In the three patients seen most recently, skin biopsy showed findings similar to those of graft-versus-host disease after bone marrow transplantation. In addition, immunologic investigation showed remarkable differences in the findings in these patients and in those who did not have a graft-versus-host disease-like syndrome after cardiac operations. In particular, interleukin-2 production in response to mitogen stimulation was markedly diminished after operation in our patients, and the ratio of OKT4+ cells to OKT8+ cells in peripheral blood was low, reflecting increased numbers of OKT8+ cells after the occurrence of symptoms. The results raise the possibility that transient depression of cellular immunity after cardiac operations with blood transfusion may contribute to the occurrence of postoperative acute graft-versus-host disease.

Aged↗

[Coronary artery bypass grafting: does the use of arterial graft for coronary artery bypass grafting increase surgical risk?].

Since April in 1988 coronary artery bypass grafting (CABG) was performed in 177 patients and the clinical results were compared in SVG-group (n = 37) in which only saphenous vein graft (SVG) was used as a graft conduit and AG-group in which one arterial graft (AG-1 group, n = 92) or more than two arterial grafts were used (AG-2 group, n = 48). In SVG-group the age was older than that in AG-group, while coronary vessels were most involved in AG-2 group and the mean number of distal anastomosis increased more in AG-group. The total pump time and aortic cross clamping time showed no significant differences among the groups. Furthermore, the occurrence of perioperative myocardial infarction, requirement of intra-aortic balloon pumping, frequency of re-chest open for hemorrhage, or sternal infection showed no significant differences among the groups. Postoperative hospital deaths were in four (three cardiac deaths) of SVG-group and four (one cardiac and two graft-versus-host disease) of AG-group. These results suggest that the use of AG does not increase surgical risk and AG can be positively used for CABG.

Adolescent↗

[Coronary artery bypass grafting in a patient with Kawasaki disease].

A 3-year-girl admitted because of angina at rest. She had been diagnosed as Kawasaki disease at the age of 3 months. At that time, a coronary aneurysm was detected by echocardiogram and aspirin had started to administer. At the age of 4 months, a cardiac arrest occurred after severe heart attack because of inferior myocardial infarction. At the age of 2 years and 6 months, she started to complain of a chest pain even at rest. Coronary angiography was performed, and it showed total occlusion of RCA and LAD. However, LAD was vaguely filled by collateral flow from diagonal branch, and 201Tl scintigraphy showed myocardial viability of anteroseptal area. At operation, the size of ITA was 1.2 mm in diameter. Coronary artery bypass grafting to LAD by ITA was performed. Three weeks postoperatively, graft patency was confirmed by coronary angiography. The girl discharged with good ability of exercise. The ITA seemed to be the first choice of conduit for CABG even in a small child, and to be useful for progressive surgical treatment of Kawasaki disease.

Child, Preschool↗

Roles of hormones in plasma potassium alteration in acute respiratory acidosis in dogs.

The present study was conducted to examine the roles of hormonal factors in plasma potassium alterations in acute respiratory acidosis. Respiratory acidosis (pH, 7.07-7.10) induced by the inhalation of 10% CO2, 20% O2 and 70% N2 mixed gas caused an increase in the plasma potassium concentration beyond that of the control of 3.44 +/- 0.12 (mean +/- SE) to 4.36 +/- 0.07 mEq/l (p less than 0.01) within 180 min. The plasma norepinephrine concentration was also noted to significantly increase at the same time. Phentolamine (40 micrograms/kg/min i.v.) did not affect the degree of acidosis or acidosis-induced hyperkalemia. No significant changes in the plasma levels of epinephrine, insulin, glucagon, cortisol or aldosterone could be detected. Hormonal factors would thus appear not to be essential to potassium movement from intracellular to extracellular compartments in acute respiratory acidosis.

Acidosis, Respiratory↗

[Advantage of internal thoracic artery for coronary arterial bypass surgery in patients over 70 years of age].

Between April 1988 and September 1991, 16 among 23 patients over 70 years of age underwent coronary bypass grafting (CABG) with at least one arterial graft. The age ranged from 70 to 77 years (mean, 72.1 years) and involved coronary lesions were two vessels in two patients and three vessels in 14 patients. Seven patients with unstable angina received emergency CABG. The number of distal anastomosis with arterial graft was mean of 1.3 per patient and left internal thoracic artery (ITA) was used as a pedicled graft in all patients. Sequential grafting with left ITA arterial graft was performed in two and right gastroepiploic artery was concomitantly used in three patients. No atherosclerosis was seen in left ITA, however, poor quality saphenous vein graft (SVG) was in five and atherosclerosis of ascending aorta was in five patients. After operation deep vein thrombosis of leg after harvesting SVG occurred in one patient. The angiogram performed within one month of operation in nine patients showed that the patency rate of arterial graft was 100% and that of SVG was 94.4%. The longest follow-up period was 42 months and New York Heart Association Functional Class improved to Class I or II in all patients. The use of pedicled ITA in elderly patient showed advantage for diseased ascending aorta and it seemed to prevent the postoperative complication due to the use of SVG.

Aged↗

[Immune gene rearrangement as markers of hematological malignancies].

Molecular genetical analysis using Ig and TCR genes has been applied for hematological malignancies. In acute leukemias, this method is used to clarify the cellular lineage, and in malignant lymphomas to detect the monoclonal component. In this article, we describe the mechanism of immune gene rearrangement and the present status and future directions of immunogenetic analysis of leukemias and lymphomas.

Gene Rearrangement, T-Lymphocyte↗

[Study on reoperation in cardiac disease].

Between January in 1988 and September in 1990, 65 patients underwent reoperation for acquired heart disease. Previous operations were closed mitral commissurotomy in 19, open mitral commissurotomy in 19, mitral valve replacement in 22, aortic valve replacement in one, and mitral repair in 4. After median sternotomy performed by hand-operated chisel and hammer, minimized dissection of the adhesive lesion was achieved. During the sternotomy, two patients required additional right thoracotomy because of marked median sternal adhesion and major cardiovascular injury occurred in three patients. Cardioplegic solution was introduced in normograde fashion except in two patients. In two patients with previous MVR by porcine prosthesis severe calcification was found in the left atrial wall and the prosthesis was not removed in one. Postoperative complications were low cardiac output syndrome requiring intra-aortic balloon pumping in two, re-thoracotomy due to hemorrhage in one, and mild air embolism without neurological damage in two. There was one early death (1.5%) but no late death. Although perioperative complication seemed to increase in reoperation, post-reoperative results was as good as those in the primary cardiac operation and reoperation on cardiac surgery should be performed before losing the indication for operation.

Adult↗