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Biomedical subjects

R Ogawa

Publications and source records attributed to R Ogawa.

At least 55 records · Page 3Linked to original sources
PubMed2001

von Recklinghausen disease complicated by pulmonary hypertension.

Two patients with von Recklinghausen disease (neurofibromatosis type 1) were admitted to the hospital because of progressive heart failure. Both patients had prominent pulmonary hypertension revealed on cardiac catheterization. A lung perfusion scan did not show any gross defect. There were no underlying causes of pulmonary hypertension in either patient, such as chronic lung disease, congenital or acquired heart disease, deep vein thrombosis, or systemic hypercoagulable states. There may be an unrecognized association between von Recklinghausen disease and pulmonary hypertension.

Adult↗
PubMed2001

Crucial role of donor-derived stromal cells in successful treatment for intractable autoimmune diseases in mrl/lpr mice by bmt via portal vein.

We have recently established a new bone marrow transplantation (BMT) method for the treatment of intractable autoimmune diseases in MRL/lpr mice; the method consists of fractionated irradiation (5.5 Gy x 2), followed by BMT of whole bone marrow cells (BMCs) from allogeneic C57BL/6 mice via the portal vein (abbreviated as 5.5 Gy x 2 + PV). In the present study, we investigate the mechanisms underlying the early engraftment of donor-derived cells in MRL/lpr mice by this method. In the mice treated with this method, the number of donor-derived cells possessing the mature lineage (Lin) markers rapidly increased in the BM, spleen, and liver; almost 100% were donor-derived cells by 14 days after the treatment. The number of donor-derived hemopoietic progenitor cells (defined as c-kit(+)/Lin(-) cells) increased in the BMCs, hepatic mononuclear cells, and especially spleen cells by 14 days after the treatment. Simultaneously, hemopoietic foci adjoining donor-derived stromal cells were observed in the liver when injected via the PV, but not via the peripheral vein (i.v.). When adherent cell-depleted BMCs were injected via the PV, recipients showed a marked reduction in the survival rate. However, when mice were transplanted with adherent cell-depleted BMCs with cultured stromal cells, all the recipients survived. These findings suggest that not only donor hematopoietic stem cells (HSCs) but also donor stromal cells administered via the PV were trapped in the liver, resulting in the early engraftment of donor HSCs in cooperation with donor-derived stromal cells. This new strategy to facilitate the early recovery of hemopoiesis would therefore be of great advantage in human application.

Animals↗
PubMed2001

Thickening of sphenoid sinus mucosa during the acute stage of pituitary apoplexy.

The authors treated two patients with pituitary apoplexy in whom magnetic resonance (MR) images were obtained before and after the episode. Two days after the apoplectic episodes, MR imaging demonstrated marked thickening of the mucosa of the sphenoid sinus that was absent in the previous studies. The relevance of this change in the sphenoid sinus was investigated. Retrospective evaluations were performed using MR images obtained in 14 consecutive patients with classic pituitary apoplexy characterized by acute onset of severe headache. The mucosa of the sphenoid sinus had thickened predominantly in the compartment just beneath the sella turcica, in nine of 11 patients, as ascertained on MR images obtained within 7 days after the onset of apoplectic symptoms. This condition improved spontaneously in all four patients who did not undergo transsphenoidal surgery. The sphenoid sinus mucosa appeared to be normal on MR images obtained from three patients at the chronic stage (> 3 months after onset). The incidence of sphenoid sinus mucosal thickening during the acute stage was significantly higher in the patients with apoplexy than that in the 100 patients without apoplexy. A histological study conducted in four patients who underwent transsphenoidal surgery during the early stage showed that the subepithelial layer of the sphenoid sinus mucous membrane was obviously swollen. The sphenoid sinus mucosa thickens during the acute stage of pituitary apoplexy. This thickening neither indicates infectious sinusitis nor rules out the choice of the transsphenoidal route for surgery.

Acute Disease↗
PubMed2001

Serum levels of interleukin 6 and stress related substances indicate mental stress condition in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate the influence of mental stress on the neuroendocrine-immune system in patients with rheumatoid arthritis (RA). METHODS: Twenty-two patients with RA and 8 patients with osteoarthritis (OA) who underwent total knee or hip arthroplasties under general anesthesia were enrolled in the study. The blood levels of interleukin 6 (IL-6) and other substances related to stress were measured just before administering anesthesia on the day of the operation when the patients lay on the operating table and roughly 30 min later when the patients were under general anesthesia without mental stress. These values were compared with those at the same time on the day before the operation, which were considered the control levels. RESULTS: In patients with RA, the levels of IL-6, cortisol, and epinephrine in the peripheral blood were significantly increased under mental stress, before anesthesia (p < 0.01). However, under general anesthesia, the IL-6, cortisol, and epinephrine were significantly decreased, compared with the levels before anesthesia (p < 0.01). Such changes were not apparent in patients with OA. The levels of other substances in the peripheral blood known to be related to stress, such as corticotropin-releasing factor, dopamine, and norepinephrine, showed no changes in patients with RA or OA. CONCLUSION: In patients with RA, excessive mental stress should be eliminated to modify the interaction between the stress-immune system and stress-endocrine system as a method to better control disease activity.

Aged↗
PubMed2001

[Current situation and problems inherent to long-term home medical care as compared with medical care provided in nursing homes].

We compared 18 patients under long-term home medical care and 11 patients who entered a nursing home after receiving home medical care, to analyze the factors thought to influence continuation of home care. There was no statistical difference between the mean age of both groups, but the mean age of main caretakers in the former (mean 59 years old) was lower compared with that of caretakers in the latter (mean 70 years old). There were various reasons for them to enter a nursing home after receiving home care. Five of the 11 patients entered the nursing home after long-term hospitalization in spite of no deterioration in their degree of handicap at discharge. We think the long-term hospitalization may reduce the motivation of caretakers. It is indicated that the age of caretakers and ability, especially motivation to provide care are important factors to continue home medical care.

Aged↗
PubMed2000

Lean body mass and body fat distribution in participants with chronic low back pain.

BACKGROUND: Loss of muscle mass and central obesity progress with aging, but the effect of muscle loss on chronic low back pain has not been precisely evaluated. METHODS: Three hundred thirty Japanese persons aged 45 to 69 years, with a complaint of low back pain for longer than 3 months (n = 203) and age- and sex-matched healthy control subjects (n = 127), were enrolled in this study. Participants with chronic low back pain were classified into the following groups: (1) women with a positive straight leg raise test result, (2) women with a negative straight leg raise test result, (3) men with a positive straight leg raise test result, and (4) men with a negative straight leg raise test result. Controls were classified by sex into a female and a male group. Anthropometric data, consisting of body mass index, percentage body fat, waist-hip ratio, and lean body mass of the upper extremities, trunk, and lower extremities divided by body weight, were measured in participants with low back pain, and the results were compared with those of controls. RESULTS: The waist-hip ratio in women with a negative straight leg raise test result was significantly higher than those in the female control group (P<.001) and in the women with a positive straight leg raise test result (P =.04). The lean body mass of the trunk and lower extremities divided by body weight of women with a negative straight leg raise test result was significantly lower than that of female controls (P =.03 for the trunk and P<.001 for the lower extremities). However, no significant differences were detected between the female negative straight leg raise test result group and the female control group for lean body mass of the upper extremities divided by body weight or body mass index. There were no significant differences in anthropometric data between the male test and control groups or between the female positive straight leg raise test result group and the female control group. CONCLUSION: Trunk and lower extremity loss of muscle mass and central obesity may be risk factors for chronic low back pain without a positive straight leg raise test result in women aged 45 to 69 years. Arch Intern Med. 2000;160:3265-3269.

Adipose Tissue↗
PubMed2000

Treatment of intractable autoimmune diseases in MRL/lpr mice using a new strategy for allogeneic bone marrow transplantation.

A new bone marrow transplantation (BMT) method for treating severe autoimmune diseases in chimeric resistant MRL/lpr mice is presented. The method consists of fractionated irradiation (5.5 Gy x 2), followed by portal venous (PV) injection of whole bone marrow cells (BMCs) from allogeneic normal C57BL/6 (B6) mice and intravenous (IV) injection of whole B6 BMCs 5 days after the PV injection (abbreviated as 5.5 Gy x 2 + PV + IV). All recipients survived more than 1 year after this treatment (more than 64 weeks after birth). Abnormal T cells (Thy1.2(+)/B220(+)/CD3(+)/CD4(-)/CD8(-)) present in MRL/lpr mice before the treatment disappear, and hematolymphoid cells are reconstituted with donor-derived cells. The treated mice are free from autoimmune diseases. Levels of autoantibodies (IgG/IgM anti-ssDNA antibodies and IgG/IgM rheumatoid factors) decrease to normal levels. Successful cooperation is achieved among T cells, B cells, and antigen-presenting cells (APCs) of the treated MRL/lpr mice when evaluated by in vitro anti-SRBC responses. Newly developed T cells are tolerant to both donor (B6)-type and host (MRL/lpr)-type major histocompatibility complex (MHC) determinants. These findings clearly indicate that severe autoimmune diseases in MRL/lpr mice are completely ameliorated by the treatment without recourse to immunosuppressants, and that the treated MRL/lpr mice show normal immune functions, strongly suggesting that this strategy would be applicable to humans. (Blood. 2000;95:1862-1868)

Animals↗
PubMed2000

What is the optimal dose of glucose administration during minor surgery under sevoflurane anesthesia?

PURPOSE: We attempted to identify the optimal infusion rate of glucose to maintain an appropriate usage of energy sources during minor surgery after an overnight fast. METHODS: Forty patients scheduled for tympanoplasty or skin grafting under sevoflurane anesthesia were assigned to four groups. The patients received a 2-h infusion of either saline or glucose at a rate of 0.1, 0.2, or 0.3 g.kg(-1).h(-1). Blood samples were collected before the induction of anesthesia, and at 1 and 2 h after the start of the saline or glucose infusion. Plasma glucose, free fatty acid, beta-hydroxybutyrate, acetoacetate, and immunoreactive insulin were measured. RESULTS: Plasma glucose concentration increased dose-dependently. Immunoreactive insulin levels increased in the groups receiving 0.2 or 0.3 g.kg(-1).h(-1) of glucose infusion. Free fatty acid and ketone bodies did not increase in any glucose infusion groups. The arterial ketone body ratio increased to over 1.00 in the groups receiving 0.2 or 0.3 g.kg(-1).h(-1) of glucose infusion. Glycorrhea was observed only in the group receiving 0.3 g.kg(-1).h(-1) of glucose. CONCLUSION: The smaller doses of glucose (0.1-0.2 g.kg(-1).h(-1)) prevented lipolysis and hyperglycemia during minor surgery.

Journal Article↗
PubMed2000

Optimal dose and duration of glucose administration during fasting period preceding surgery in rabbits.

PURPOSE: We examined preoperative glucose administration to establish what dose and cutoff point were optimal for suppression of lipolysis and prevention of hypo- or hyperglycemia. METHODS: Rabbits were preoperatively fasted and simultaneously received glucose at a constant rate of 0, 0.1, 0.2, 0.3, or 0.4 g.kg(-1).h(-1) in fluid infusion for 3 h. Plasma glucose, immunoreactive insulin activity, nonesterified fatty acids, and ketone bodies were measured 0, 1.5, 3 and 4 h after the start of infusion, and hepatic glycogen content was assessed 1 h after cessation of infusion. RESULTS: Fluid infusion without glucose decreased plasma glucose. Glucose administration at more than 0.2 g.kg(-1).h(-1) caused hyperglycemia (>200 mg.dl(-1)) in the infusion period; the differences were significant compared with the value at zero time or in the 0 g.kg(-1).h(-1) group (P < 0.01). The highest dose also raised plasma immunoreactive insulin activity, which was significantly higher than in the 0 g.kg(-1).h(-1) group (P < 0.01) at the midpoint of the infusion period. Plasma nonesterified fatty acids increased in all groups. The changes were, however, significantly reduced in both the 0.3 and 0.4 g.kg(-1).h(-1) groups (P < 0.05 and P < 0.01, respectively) by the end of infusion. All these effects of glucose supply, including suppression of lipolysis, disappeared regardless of dose within 1 h after the cessation of infusion. CONCLUSION: These results suggest that the optimal dose for preoperative glucose infusion, in order to preserve carbohydrate or fat metabolism, is 0.1-0.2 or 0.3 g.kg(-1).h(-1), respectively, and indicate that administration should not be discontinued until the start of surgery.

Journal Article↗
PubMed2000

Changes in hemodynamic variables and catecholamine levels after rapid increase in sevoflurane or isoflurane concentration with or without nitrous oxide under endotracheal intubation.

PURPOSE: Rapid increases in concentrations of isoflurane and desflurane in oxygen have been shown to increase sympathetic activity. The aim of this study was to determine whether concomitant administration of nitrous oxide would reduce these sympathomimetic effects of volatile anesthetics. METHODS: Eighty healthy patients in whom the trachea was intubated and mechanically ventilated were given 15 min of anesthesia with either N(2)O (67%)-O(2)-sevoflurane (GOS), O(2)-sevoflurane (OS), N(2)O (67%)-O(2)-isoflurane (GOI), or O(2)-isoflurane (OI) (n = 20 per group). The inspired concentration of sevoflurane was 0.85% (0.5 minimum alveolar concentration [MAC]), and that of isoflurane was 0.6% (0.5 MAC). Fifteen minutes after endotracheal intubation, baseline and arterial blood sample data were obtained. Immediately after that, a sudden administration of 2.9 MAC volatile anesthetics was performed. Systolic and diastolic arterial pressures, heart rate, and end-tidal carbon dioxide concentration were obtained at 0.5, 1, 1.5, 2, 3, 4, and 5 min after that. To measure catecholamine levels, arterial blood samples were obtained 2 and 5 min after the trial started. RESULTS: Except for the OI group, systolic and diastolic arterial pressure progressively decreased after the abrupt increase in the concentration of volatile anesthetics. Except for the OS group, the heart rate increased after the abrupt increase in the concentration of volatile anesthetics. In the OI group, the end-tidal concentration of carbon dioxide increased at 0.5 and 1 min, suggesting that a slight hyperdynamic state occurred. However, it decreased progressively after the abrupt increase in volatile anesthetic concentration in the other groups. Plasma norepinephrine levels increased progressively in all groups. CONCLUSION: Even if nitrous oxide was added to isoflurane or sevoflurane, the increase in heart rate could not be avoided. Contrary to previous reports, severe hyperdynamic circulation was not observed after a rapid increase in isoflurane concentration.

Journal Article↗
PubMed2000

Control engineering and electromyographic kinesiology analyses of normal human gait.

In this study, we analyzed the electrical activity patterns of the antagonistic bi-articular and mono-articular muscles of both legs during normal gait cycles, in terms of electromyographic (EMG) kinesiology and control engineering. For control engineering analyses, we utilized a mechanical two-joint link model equipped with antagonistic pairs of bi-articular and mono-articular muscles. It was confirmed that the coordinated activity pattern, in which the bi-articular muscles of the rectus femoris (Rf) and the medial hamstrings (Mh) showed criss-cross EMG patterns, and the mono-articular muscles of the gluteus maximus and the vastus medialis showed sustained activities during the early stance phase in the gait cycle, contributed to the output force control and the output force direction control. Reversal of Rf and Mh activities was responsible for changes in the output force direction during the heel contact period. The results obtained here strongly highlight the importance of and necessity for control engineering evaluation of coordinated muscle activities of bi-articular and mono-articular antagonistic muscles for analyses not only of gait but also of sports injuries.

Adolescent↗
PubMed2000

Biomechanical study of gait using an intelligent brace.

We have developed a new long leg brace fitted with a computer-controlled knee joint that allows the user to go up and down a slope and stairs. Using this new brace, we analyzed gait under various conditions in ten normal men in terms of dynamic electromyography. Walking up a slope with normal step produced discharges in the leg muscles other than the gastrocnemius lateral head before and after the heel-strike on the ground, which indicated the absorption of the impact of landing. Going down a slope with controlled step resulted in lower activities of the tibialis anterior and the gastrocnemius lateral head than doing so with non-locked step or locked step. In subjects walking up stairs with tandem gait, the large discharges of the gastrocnemius lateral head that were observed in the late stance phase with normal step disappeared when the brace was applied. These results indicated that the muscle activity levels decreased during controlled walking with this new brace, and that the new brace can compensate for reduced muscle strength of the lower leg during walking. Kinematic analysis of walking revealed no significant difference between normal walking and controlled walking under any walking conditions.

Adult↗
PubMed2000

Minor cardiac troponin T release in patients undergoing coronary artery bypass graft surgery on a beating heart.

OBJECTIVES: To determine whether and to what extent coronary artery bypass graft (CABG) surgery without extracorporeal circulation is associated with cardiac troponin T (TnT) release. DESIGN: Prospective study. SETTING: A single university hospital. PARTICIPANTS: Twenty-three patients scheduled for minimally invasive CABG surgery. Sixteen patients received one coronary anastomosis, and seven received two. INTERVENTIONS: TnT and creatine kinase-MB (CK-MB) levels were determined immediately before induction of anesthesia (baseline) and at 0, 12, and 24 hours after surgery. Hemodynamic measurements were made, and 5-lead electrocardiograms with continuous automated ST-segment trends were analyzed. MEASUREMENTS AND MAIN RESULTS: All patients had a good cardiac outcome. Median cumulative coronary artery occlusion time was 27 minutes (range, 10 to 49 minutes). TnT levels were undetectable in 91.3% of patients at baseline when a detection limit of 0.01 ng/mL was employed. TnT and CK-MB showed significant elevations at 12 and 24 hours versus baseline. Postoperatively, TnT was detectable in 91.3% of patients, and 17.4% suffered minor myocardial damage, as evidenced by an abnormal increase in TnT greater than 0.2 ng/mL, excluding those exhibiting myocardial infarction. ST segment changes developed in seven patients, persisting for 13.0 minutes (range, 9.5 to 15.8 minutes) and disappearing immediately after coronary artery clamp release. There were no significant correlations between cumulative coronary occlusion time and peak TnT or CK-MB levels. CONCLUSIONS: TnT was detected after surgery in most patients, and significant TnT levels indicative of myocardial injury (>0.2 ng/mL) were detected in only 17% of patients, probably as a result of brief periods of coronary artery occlusion.

Adult↗
PubMed2000

Local cardiac wall stabilization influences the reproducibility of regional wall motion during off-pump coronary artery pass surgery.

OBJECTIVE: Myocardial ischemia is a risk factor during off-pump coronary artery bypass procedures. The development of new regional wall motion abnormalities assessed by transesophageal echocardiography (TEE) is a very sensitive sign of myocardial ischemia. To facilitate anastomosis, the epicardial area of the anastomosis site is often immobilized by a "stabilizer." This study was designed to investigate whether cardiac wall stabilization with an epicardial stabilizer could affect the interpretation of wall motion during coronary anastomosis without cardiopulmonary bypass. METHODS: The TEE videotapes of 15 adult patients were investigated. Left ventricular (LV) transgastric short and long axis views were divided according to a modified 16-segment method. LV wall motion was scored using a 5-grade scale by two independent blinded investigators during pre-occlusion, occlusion, and reperfusion of anastomosed coronary arteries. The wall motion scores of a stabilized segment combined with two adjacent segments were compared with those of non-stabilized segments. Interobserver agreement was assessed using the weighted kappa statistic. RESULTS: A total of 216 segments were analyzed by two investigators. The interobserver kappa coefficient in pre-occlusion and reperfusion periods was 0.87, 0.87 and 0.86, 0.87, respectively, indicating high agreements without stabilizer. During the occlusion period in stabilized and non-stabilized segments, it was 0.59 and 0.76, respectively, showing significantly less reproducibility in the presence of stabilizer. CONCLUSION: Cardiac wall stabilization affects the reproducibility in the interpretation of regional wall motion during off-pump coronary artery bypass surgery. Caution should be used when monitoring for myocardial ischemia using TEE during coronary artery bypass surgery with epicardial stabilizer.

Coronary Artery Bypass↗
PubMed2000

Suppression of surgical hyperaldosteronism by potassium canrenoate during gynecologic surgery under sevoflurane anesthesia.

BACKGROUND: Surgical hyperaldosteronism leads to sodium and water retention during surgery and often causes postoperative edema. This study investigated the effect of potassium canrenoate (PC) on pituitary adrenocortical function in lower abdominal surgery under sevoflurane anesthesia. METHODS: Twenty patients were randomized to receive 400 mg of PC (the PC group, n=10) or saline (the control group, n=10) intravenously. The following parameters were determined: plasma aldosterone, adrenocorticotropic hormone (ACTH), plasma renin activity (PRA), serum sodium and potassium, urinary sodium and potassium, and urine output. RESULTS: The aldosterone and ACTH levels showed significant increases in the control group during surgery. Plasma ACTH also increased significantly in the PC group, but plasma aldosterone levels were unchanged during surgery. The urine Na/K ratio of the PC group was significantly higher than that of the control group. CONCLUSION: The present study suggested that PC suppresses the increase of plasma aldosterone caused by surgical stress. That may prevent sodium retention and potassium excretion during surgery.

Adrenocorticotropic Hormone↗
PubMed2000

Role of inflammatory mediators in lipid A analogue (ONO-4007)-induced vascular permeability change in mouse skin.

1. Endotoxin shock is accompanied by an increase in peripheral vascular permeability. It has been postulated that most biological activities of LPS are derived from lipid A moiety. Here we examined the effect of lipid A analogue ONO-4007 in increasing vascular permeability and the possible mediators in mouse skin by a dye leakage method. 2. Subcutaneous injection of ONO-4007 (1 - 2 mg site(-1)) induced a dose-dependent increase in vascular permeability which was evident after 120 min. 3. ONO-4007-induced dye leakage was significantly attenuated by pretreatments with anti-tumour necrosis factor-alpha (TNF-alpha) and anti-interleukin-1alpha (IL-1alpha) antibodies, but not with indomethacin (5 mg kg(-1)) or diphenhydramine (10 mg kg(-1)). ONO-4007-induced dye leakage was significantly inhibited by a pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME) (10 mg kg(-1)) but not with aminoguanidine (50 mg kg(-1)). In inducible nitric oxide synthase (iNOS)-deficient mice, ONO-4007 significantly increased the dye leakage, while ONO-4007 dilated rat thoracic aortic rings pre-contracted with phenylephrine, and the L-NAME pretreatment inhibited the dilation. 4. Thus, TNF-alpha, IL-1alpha and constitutive NOSs-derived nitric oxide but not prostaglandins or histamine play a role in ONO-4007-induced increase in vascular permeability. Although ONO-4007 mimics LPS in increasing vascular permeability, mechanisms of permeability change elicited by ONO-4007 were not identical to those of LPS.

Animals↗
PubMed2000

Myocardial dysfunction associated with proinflammatory cytokines after esophageal resection.

UNLABELLED: Proinflammatory cytokines have been implicated in mediating myocardial dysfunction associated with major surgery. We investigated the profile of proinflammatory cytokines and the association of cytokine levels with myocardial function after esophagectomy. We studied 12 patients who underwent subtotal esophagectomy. One patient died of multiple organ failure. This patient had the largest interleukin-6 (IL-6) level of all the subjects. IL-6 levels increased from 14.9 +/- 8.7 pg/mL to 498.4 +/- 294.3 pg/mL (P < 0.05) at 6 h postoperatively. Interleukin-8 (IL-8) levels also significantly increased postoperatively. Right ventricular ejection fraction (RVEF) decreased from 44% +/- 1% to 36% +/- 2% (P < 0.05) and 37% +/- 2% (P < 0.05) at 6 h and 12 h postoperatively. Stroke volume index (SVI) decreased significantly at the end of operation and at 6 h and 12 h postoperatively. The changes of RVEF and SVI showed an independent negative correlation with the IL-6 level (r = -0.70, P < 0.001 and r = -0.62, P < 0.001, respectively). In contrast, the change of RVEF and SVI was not correlated with the IL-8 level. Esophagectomy is associated with transient depression of myocardial function. IL-6 may contribute to this postoperative myocardial dysfunction. IMPLICATIONS: We examined the association between myocardial function and proinflammatory cytokines after esophagectomy. Interleukin-6 may be the cytokine that most sensitively reflects the postoperative myocardial dysfunction.

Carcinoma, Squamous Cell↗