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T Akimoto

Publications and source records attributed to T Akimoto.

At least 163 records · Page 9Linked to original sources
PubMed1994

[Investigation of the development of dermatitis in hypotrichotic rats--microbiological study].

The hereditary hypotrichotic (WBN/IIa-Ht) rat is affected by dermatitis characterized by erosions and crust formation on dorsal skin areas. The bacterial flora of this dermatitis and the normal skin of the hypotrichotic rat was examined. As controls the cutaneous flora of atrichotic and Wistar rats was examined, and the results compared with those in hypotrichotic rats. The total number of bacterial colonies from the lesions and normal skin of hypotrichotic rats were 3.9 x 10(5) to 1.16 x 10(8) CFU/cm2 and 1.6 x 10(3) to 1.8 x 10(4) CFU/cm2, respectively. In the lesions, overwhelming numbers of S. aureus were detected as almost pure cultures. In the normal skin, S. aureus was predominant, accounting for about 90% of all bacteria. The total number of bacterial colonies in the atrichotic rats was the same as in the hypotrichotic rats. The majority of the isolates were Staphylococcus sp., and about half of them were identified as S. aureus. The total number of bacterial colonies from the skin of individual Wistar rats varied extremely, ranging from 64 to 2.98 x 10(5) CFU/cm2. The flora mainly consisted of coagulase-negative Staphylococcus (CNS), S. aureus, and alpha-hemolytic Streptococcus sp., and CNS was isolated most frequently. Histopathological examination of the eroded portions in hypotrichotic rats revealed many clusters of coccoid bacteria and neutrophilic cell infiltration of the epidermis. These findings suggest that the dermatitis in hypotrichotic rats was caused by S. aureus and affected by unknown traits of these rats.

Animals↗
PubMed1994

[Gross morphology of the pancreas and distribution of pancreatic ducts in the rat].

Gross morphology of the pancreas and distribution of pancreatic ducts were investigated in 12 Jcl: Wistar rats. The pancreas consisted of a body and two (right and left) lobes. The pancreatic body was located along the cranial part of the duodenum. The right lobe extended into the duodenal ligament, while the left lobe extended toward the spleen into the gastrolienal ligament. In 9 animals, the number of ducts ranged between 3 and 10. Each duct joined the hepatoenteric duct. Two (right and left) large ducts found in all animals drained the right and left lobes. Other ducts observed in more than a half of the animals drained either the body or a part of the lobe.

Animals↗
PubMed1994

Prognostic factors of poorly-differentiated squamous cell carcinoma of the nasopharynx.

Retrospective analysis was performed with intent to evaluate prognostic factors in radiation therapy for 72 patients with histologically confirmed poorly-differentiated squamous cell carcinoma of the nasopharynx. The 10-year overall actuarial and cause specific survival rates were 36 and 40%, respectively. The median survival time was 43 months. Sixteen patients survived for more than 10 years (maximum 297 months). The five- and 10-year cause specific survival rates for Stages I, II, III and IV disease were 100 and 100%, 80 and 27%, 83 and 83%, and 38 and 31%, respectively. Two patients with Stage II disease died of a re-recurrent tumor more than seven years after their initial treatment. There was a significant difference between the survival curve for Stage I or III disease and that for Stage IV disease (P < 0.05). The patients with a T1-3 tumor had a statistically better survival rate than those with a T4 tumor (T1:T4, P < 0.001, T2 or T3:T4, P < 0.05). The patients with N0 had statistically better survival rates than those with N3 (P < 0.01). Twenty-eight patients developed loco-regional recurrence. Twenty-one patients developed distant bone metastases, most of which occurred within a year of the initiation of radiation therapy. The survival for the patients with loco-regional recurrence was nearly the same as that for the patients without loco-regional recurrence. The 10-year survival rates for patients with and without distant bone metastases were 0 and 48%, respectively (P < 0.001). Multivariate analysis revealed that the parameters influencing cause specific survival were stage categories of T and N, and adjuvant chemotherapy, whereas those influencing loco-regional recurrence were only stage categories of T and N. The only parameter to influence distant bone metastases was sex. We concluded the most important cause of failure for the patients with poorly-differentiated squamous cell carcinoma of the nasopharynx to be distant bone metastases.

Adolescent↗
PubMed1994

[A case report of aortic valve replacement after 16 years from repair of ruptured sinus Valsalva aneurysm].

A case of aortic valve replacement after 16 years from the repair of ruptured sinus valsalva aneurysm (RSVA) was reported. The patient has undergone direct closure of RSVA with VSD type I at 34 years old. At the operation, no attempt was made as to aortic valve regurgitation because of small regurgitation, Selloers 1 on aortography. At 50 years old, he developed dyspnea on exertion, to-and-fro murmur due to aortic valve regurgitation, Selloers 3. Aortic valve replacement, we confirmed the completely closure of right coronary sinus valsalva, and histopathologically observed the degenerative change of only right coronary cusp.

Aortic Aneurysm↗
PubMed1993

Characteristics of 45Ca uptake stimulated by high KCl of differentiated and undifferentiated NG108-15 and PC12h cells.

The characteristics of KCl-stimulated 45Ca uptake by neuroblastoma X glioma hybrid NG108-15 cells induced to differentiate with dibutyryl cAMP (Bt2cAMP) and of PC12h pheochromocytoma cells induced to differentiate with nerve growth factor (NGF) were studied. The extent and rate of KCl-stimulated 45Ca uptake by differentiated NG108-15 cells induced with Bt2cAMP were significantly higher than those of the undifferentiated cells. However, differentiation of PC12h cells induced with NGF did not enhance their extent or rate of KCl-stimulated 45Ca uptake. The effects of Ca agonist and antagonists indicated that the characteristics of KCl-stimulated 45Ca uptake by Bt2cAMP-treated NG108-15 cells and NGF-treated PC12h cells mainly reflected those of peripheral L-type voltage-sensitive calcium channels activated by high KCl. These results suggest that differentiated neural cells did not all show an enhanced capacity for KCl-stimulated 45Ca uptake, although the characteristic patterns of differentiation (extension of neurite-like processes, etc.) and that of effect by Ca agonist or antagonists on NG108-15 cells and PC12h cells were similar.

Animals↗
PubMed1993

Specific bindings of [3H](+)PN200-110 and [125I]omega-conotoxin to crude membranes from differentiated NG108-15 cells.

The characteristics of the specific bindings of [3H](+)PN200-110 (PN: L-type Ca channel antagonist) and [125I]omega-conotoxin G VI A (omega-CgTX: neuronal L- or N-type Ca channel antagonist) to crude membranes from undifferentiated neuroblastoma X glioma hybrid NG108-15 (NG108-15) cells and differentiated cells induced with dibutyryl cAMP (Bt2cAMP) were examined, because we have already observed that the magnitude and rate of KCl-stimulated 45Ca uptake by NG108-15 cells increased progressively during differentiation of the cells induced with Bt2-cAMP (unpublished results). The specific binding of [3H](+)PN to these crude membranes was saturable at various concentrations of 2.5-5.0 nM [3H](+)PN. Scatchard analysis showed that the specific binding of [3H](+)PN at equilibrium was significantly increased after differentiation of the NG108-15 cells with Bt2cAMP, but that the apparent Kd value for the specific binding of [3H](+)PN was not influenced by treatment with Bt2cAMP. The specific binding of [3H](+)PN to crude membranes from Bt2cAMP-treated NG108-15 cells was inhibited by a calcium agonist and antagonists, the order of their inhibitory potencies being (+)PN > nitrendipine > (-)PN > or = Bay K 8644 > > diltiazem = verapamil. Thus, PNs showed significant stereoselective inhibition of the specific binding of [3H](+)PN. On the other hand, [125I]omega-CgTX at concentrations of 0.075-0.6 nM showed scarcely any specific binding to these crude membranes, although at 0.6 nM it showed specific binding to crude membranes from rat brain in the same experimental conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1993

Characteristics of specific 125I-omega-conotoxin GVIA binding in rat whole brain.

Characteristics of specific 125I-omega-conotoxin (omega-CgTX) binding were systematically investigated in crude membranes from rat whole brain. Kd and Bmax Values for the binding were 49.7 pM and 181.5 fmol/mg of protein, respectively. The effects of various types of Ca channel antagonists on the binding were investigated. Dynorphin A (1-13), in particular, specifically inhibited 125I-omega-CgTX binding, but not that of [3H](+)PN200-110. Spider venom from Plectreurys tristes did not specifically inhibit specific binding of 125I-omega-CgTX, because the venom also inhibited the binding of [3H](+)PN200-110 to a similar degree. The amount of specific binding of 125I-omega-CgTX was less in the cerebellum than that in any other area of whole brain. The cross-linker disuccinimidyl suberate did not label with 125I-omega-CgTX and its binding sites in rat whole brain, although it did in chick whole brain, which was used as a positive control. These findings suggested that dynorphine A (1-13) was a selective blocker of omega-CgTX-sensitive Ca channels in crude membranes from rat whole brain and that omega-CgTX-sensitive Ca channels were mainly present a rat brain except cerebellum.

Animals↗
PubMed1993

[Effect of retrograde cerebral perfusion in preserving cerebral function during circulatory arrest].

The efficacy of retrograde cerebral perfusion (RCP) method was evaluated in 26 patients who underwent aortic arch reconstruction. Surgical procedures were; ascending-proxymal arch replacement involving Bentall type procedures (17 cases), total arch replacement (4 cases), and distal arch replacement (5 cases). The RCP were performed through selective cannulation on the superior vena cava at 18.4 degrees C of the average rectal temperature. The perfusion pressure was 28.3 (+/- 5.9) cmH2O and flow was 360 (+/- 15.4) ml/min. RCP time was 74.1 (+/- 26.2) min. Twenty-four patients survived among 26 patients and 2 patients died after operation. Postoperative consciousness was confirmed in 25 patients. Postoperative neurological complications were 1) delayed arousal 5 cases, 2) delirium 3 cases, 3) respiratory disorders 5 cases, 4) double vision 2 cases, 5) cerebral infarction (CI) 1 case. These complications except-CI were resolved in early postoperative period. And regarding effective time period of RCP, incidence of neurological complications were significantly higher in cases which received RCP over 80 min. Therefore we consider that 80 min is a safety time period. In conclusion, RCP is a useful step for preserving the brain during the operation of graft replacement of aorta involving aortic arch.

Aortic Dissection↗
PubMed1993

[Influence of bilateral stellate ganglion block on hemodynamics].

This study was designed to investigate the influence of bilateral stellate ganglion block (SGB) on hemodynamics in 15 mongrel dogs. Following general anesthesia, each dog received SGB with 1.5% mepivacaine. Cardiovascular effect of bilateral SGB was assessed by measuring mean artery pressure (MAP), heart rate (HR), cardiac output (CO), right atrial pressure (RAP), mean pulmonary artery pressure (MPAP), pulmonary capillary wedge pressure (PCWP) and common carotid arterial blood flow (CCAF). These were measured directly by a Swan-Ganz catheter and ultrasonic blood flow meter, during the first 15 minutes after SGB. A decrease of MAP and HR was observed after bilateral SGB. CO decreased for 13% compared with the control value. However, this change was not statistically significant. There was a significant increase in the bilateral CCAF, but the degree of the increase of CCAF was greater after unilateral SGB than after the bilateral SGB.

Animals↗
PubMed1993

[Effectiveness of continuous retrograde cerebral perfusion for surgical treatment of aneurysms of the aortic arch--comparison with antegrade cerebral perfusion].

Several methods have been used for an adjunct to perform operation of aortic arch aneurysms. However, their results were often not so reasonable. Recently retrograde cerebral perfusion was reported as a new adjunctive method. In our institute, for the past 6 and a half years from May 1985 to April 1992, 50 patients underwent reconstruction of the transverse aortic arch by using two methods of artificial cerebral perfusion. One method is continuous antegrade cerebral perfusion (ACP, for 32 patients), and the other is continuous retrograde cerebral perfusion (RCP, for 18 patients), each technique was combined with deep hypothermia (18-20 degrees C) and low flow perfusion (10-30 ml/kg/min) to lower half body performed from femoral artery. In our RCP circuit, an additional pump was used for cerebral perfusion to superior vena cava, but the circuit was much simpler than the circuit in ACP. We compared the two methods (ACP versus RCP) as regards to the following items and the results were showed in parentheses; hospital death (8/32, 25%: 2/18, 11%), respiratory complication (8.27, 30%: 3/18, 17%), neurological complication (7/29, 24%: 1/18, 5.5%), duration of extracorporeal circulation (306.8 +/- 74.5 min: 260.4 +/- 60.0 min), periods of pre-ECC in the operation (160.3 +/- 69.2 min: 117.7 +/- 35.3 min), duration of cerebral perfusion (113.6 +/- 45.4 min: 74.1 30.5 min) and amount of bleeding (3424 +/- 2881 ml: 1802 +/- 1291 ml). RCP has superior advantages in all of those in comparison with ACP. These results suggest that RCP is a useful adjunctive method for reconstruction of aortic arch with a low operative risk.

Adult↗
PubMed1993

[Recent advances of surgical treatment of aortic arch aneurysm using retrograde cerebral perfusion].

Between March 1985 and September 1992, 68 patients underwent the replacement of the arch aorta. To protect the brain we had used selective cerebral perfusion (SCP) in 33 cases, but since October 1990 we have used retrograde cerebral perfusion (RCP) in 35 cases. Compared with SCP, RCP decreased the incidences of cerebral infarction and irreversible cerebral complications from 27% to 4% (p < 0.01), and hospital mortality rate from 27% to 14%. However RCP over 80 minutes made complication of transient consciousness disturbance in 4 of 7 cases (57%). We measured cerebral blood flow (CBF) by transcranial Doppler at middle cerebral arteries in 7 cases. After RCP, CBF decreased between 50% and 10% and could not be detected in 3 cases. Reactive hyperemia occurred in all cases after RCP ended. RCP will increased circulatory arrest time by about 30 minutes according to our clinical data.

Aortic Dissection↗
PubMed1992

Effects of GTP analogues and activation of endogenous protein kinases on photoaffinity labeling with [3H](+)PN200-110 of crude membranes from rat heart and brain.

The effects of GTP analogues and conditions in which various endogenous protein kinases were activated on photoaffinity labeling with [3H](+)PN200-110 (PN) of crude membranes from rat cardiac muscle and whole brain were investigated. Photoaffinity labeling with 20 nM [3H](+)PN of these crude membranes was decreased by 100 microM GTP-gamma-S, but not by 100 microM GTP or 100 microM GDP-beta-S. Similar results were obtained on the effects of GTP and its analogues on the specific binding of 20 nM [3H](+)PN to these crude membranes under the same conditions. Activation of endogenous protein kinases in these crude membranes did not influence the photoaffinity labeling with [3H](+)PN. These results suggested the binding sites, or DPH-sensitive, or L-type, calcium channels in curde membranes from rat cardiac muscle and whole brain are directly or indirectly modulated by endogenous GTP-binding protein, but not by various endogenous protein kinases in these crude membranes.

Affinity Labels↗
PubMed1992

[Protective effects of naftidrofuryl oxalate against hypoxia-induced death].

To analyze the effects of naftidrofuryl oxalate (LS-121) on the central nervous system exposed to critical hypoxia, survival duration was employed as a parameter of the protective effects of the drug against hypoxia-induced death. In the control group (no drug administration), the electroencephalogram (EEG) was flattened promptly after changing to hypoxia from aerobic conditions, and it was impossible to recognize precisely what time the EEG disappeared because of vigorous body movements. Arterial blood pressure (BP) was clearly recognized, and rats never recovered after BP decreased to 0 mmHg, although the electrocardiogram (ECG) was still recorded. Thus, survival duration recognized by measuring the time from the onset of hypoxia to the time when BP became 0 mmHg was considered to be a good indicator. After LS-121 (10 mg/kg) administration, survival duration was significantly prolonged compared to the control. Combination therapy of LS-121 (25 mg/kg) and bifemelane hydrochloride (BI) (25 mg/kg) also revealed the prolongation of survival duration. Neither idebenone (10 mg/kg) nor nicergoline (10 mg/kg) showed significant changes in survival duration. These findings suggest that LS-121, either with or without BI, could improve cerebrovascular disorders induced by hypoxia.

Animals↗
PubMed1992

[A case of hypersensitivity pneumonitis due to isocyanate exposure showing progression even two months after removal of the antigen].

A 68-year-old male developed dry cough and exertional dyspnea after handling paint spray containing isocyanates (TDI, MDI) for three months. Initially, the symptoms fluctuated according to whether he was at work or not. He was admitted to our hospital on February 7, 1990, because of progressive worsening of symptoms. In spite of admission to hospital and cessation of exposure to isocyanates, there was no improvement of symptoms. His chest X-ray film showed diffuse small nodular and reticular shadows. Transbronchial lung biopsy revealed thickening of the alveolar walls and formation of Masson's bodies associated with mononuclear cell infiltration in alveolar spaces. High titers of TDI-HSA and MDI-HSA specific IgG antibodies were detected by ELISA, and a high level of serum soluble IL2 receptor was also detected. From these results, we diagnosed hypersensitivity pneumonitis due to exposure to isocyanates. One week administration of prednisolone caused dramatic improvement of his symptoms, chest X-ray findings, and laboratory data. His clinical course and response to prednisolone therapy indicated that long-term steroid administration could not be avoided. The prolonged symptoms and the necessity for long-term steroid therapy are discussed.

Aged↗
PubMed1992

[Pharmacokinetic studies of menogaril (TUT-7) with rats].

Menogaril (TUT-7) is a novel antitumor antibiotic belonging to anthracyclines. The pharmacokinetic parameters derived from plasma concentration-time profiles after repeated (for 14 days) or single oral administration of TUT-7 to rats were found to be not significantly different by either administration schedule. The rats with artificial liver dysfunction were obtained by subcutaneous application of carbon tetrachloride (CCl4, 1 ml/kg) for 3 days. After oral administration of TUT-7 to the rats with CCl4-induced liver toxicity (3 daily administrations of 1mg/kg, S.C.), the maximum plasma concentrations (Cmax) and AUC of both the unchanged drug and its metabolite N-Demethyl menogaril, were increased. Also over all elimination was slower in animals with liver dysfunction.

Administration, Oral↗
PubMed1992

[Surgical versus nonsurgical therapy of fatal tachyarrhythmias].

Interventional treatment is necessary for fatal drug-refractory tachyarrhythmias. Thirty-three, 33 and 16 patients (pts) with intractable ventricular tachycardia (VT) and/or fibrillation (VF) were managed with cryosurgery (CS), electrical catheter ablation (EA) and implantable pacer-cardioverter-defibrillator (PCD), respectively. Seventy-six and 43 pts with sudden death risk in the Wolff-Parkinson-White syndrome (WPW) also underwent CS and EA, respectively. CS success rates were 85% in VT/VF and 95% in WPW. Those of EA were 48% and 81%, respectively. EA success rates were 100% (6/6) in idiopathic verapamil-sensitive VT originated from LV, 0% (0/2) in VT following TOF repair and 0% (0/2) in idiopathic VT originated from right ventricular outflow tract. A new VT developed in 5 of 11 pts with arrhythmogenic right ventricular dysplasia (ARVD) following EA. PCD was effective for prevention from sudden death in idiopathic VF and pleomorphic VT. All of pharmacologic, EA and CS therapies were relatively effective in ischemic heart disease without low EF. In conclusion, the decision of VT-VF therapy may be affected by the underlying heart disease and EA may be established as an initial intervention for high risk WPW.

Adult↗