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T Shiozaki

Publications and source records attributed to T Shiozaki.

At least 37 records · Page 2Linked to original sources
PubMed1999

Changes in left ventricular performance in patients with severe head injury during and after mild hypothermia.

OBJECTIVE: To evaluate left ventricular (LV) performance in patients with severe head injury during and after mild hypothermia. PATIENTS AND METHODS: Seven consecutive patients who underwent therapeutic mild hypothermia (age, 15 to 70 years; Glasgow Coma Scale score on admission, 4 to 8). LV performance was assessed by using M-mode, color tissue Doppler imaging tracings and pulsed Doppler echocardiography. LV contraction and relaxation were evaluated by using the peak velocity of LV posterior wall movement during systole (Smax) and diastole (Dmax), respectively, in addition to the conventional echocardiographic indices. RESULTS: Mild hypothermia increased LV ejection time and reciprocally reduced LV filling period as indicated by temperature-dependent shortening of the early diastolic filling and the total diastolic inflow time. The indices depending on temporal factors such as ejection time, Smax, or Dmax were significantly affected by mild hypothermia, whereas those depending on spatial factors such as fractional shortening or stroke volume index were not. The attenuated Smax was compensated for the prolonged ejection time resulting in the relatively consistent fractional shortening regardless of body temperature. There was no compensatory mechanism for the decreased Dmax during diastole. CONCLUSION: The effect of mild hypothermia seemed to be predominantly negatively chronotropic. LV diastolic function was more vulnerable to mild hypothermia than LV systolic function was.

Adolescent↗
PubMed1999

Little benefit from mild hypothermia therapy for severely head injured patients with low intracranial pressure.

OBJECT: This study was performed to determine whether mild hypothermia therapy is essential for the treatment of severely head injured patients in whom intracranial pressure (ICP) can be maintained below 20 mm Hg by using conventional therapies. METHODS: Sixteen consecutive severely head injured patients fulfilled the following criteria: the patient's ICP was maintained below 20 mm Hg by using fluid restriction, hyperventilation, and high-dose barbiturate therapy; and the patient had a Glasgow Coma Scale score of 8 or less on admission. After conventional therapies had been applied, the patients were divided randomly into two groups: the mild hypothermia group (HT group; eight patients) and the normothermia group (NT group; eight patients). The HT group received mild hypothermia (intracranial temperature 34 degrees C) therapy for 48 hours followed by rewarming at 1 degree C per day for 3 days, whereas the NT group received normothermia (intracranial temperature 37 degrees C) therapy for 5 days. Specimens of cerebrospinal fluid (CSF) taken from an intraventricular catheter every 24 hours were analyzed for the presence of excitatory amino acids ([EAAs] glutamate, aspartate, and glycine) and cytokines (tumor necrosis factor-alpha, interleukin [IL]-1beta, IL-6, IL-8, and IL-10). The two groups did not differ significantly in patient age, neurological status, or level of ICP. There were no significant differences in daily changes in CSF concentrations of EAAs and cytokines between the two groups. The incidence of pneumonia was slightly higher in the HT group compared with the NT group (p = 0.059). The incidence of diabetes insipidus associated with hypernatremia was significantly higher in the HT group compared with that in the NT group (p < 0.01). The two groups did not differ with respect to their clinical outcomes. CONCLUSIONS: The authors recommend normothermia therapy for the treatment of severely head injured patients in whom ICP can be maintained at lower than 20 mm Hg by using conventional therapies, because mild hypothermia therapy does not convey any advantage over normothermia therapy in such patients.

Adolescent↗
PubMed1999

[Influence of interocclusal distance of mandibular unilateral distal extension removable partial denture on masticatory function].

The purpose of this study was to elucidate the influence on masticatory function when the mandibular unilateral distal extension removable partial denture changed the interocclusal distance. The experiments, crushability, the sense of mastication, and the masticatory strokes until swallowing, were conducted, on four subjects, using the denture with the apparatus that enabled to change the interocclusal distance. The results were as follows: The particle size distribution showed that the ratio of small particle (diameter 2.5-4.5 mm) decreased, while that of large particle (more than 5.0 mm) increased, on three of four subjects, and the value of crushability diminished. A reduction of the value of crushability when the interocclusal distance was extended more than 800 microns was found. As for the other subject, no change was recognized on the particle size distribution under experimental condition, and the value of crushability showed no significant change.

Dental Occlusion↗
PubMed1998

Selection of severely head injured patients for mild hypothermia therapy.

OBJECT: The authors have analyzed the efficacy of inducing mild hypothermia (34 degrees C) in 62 severely head injured patients to control fulminant intracranial hypertension. METHODS: All 62 patients fulfilled the following criteria: 1)persistent intracranial pressure (ICP) greater than 20 mm Hg despite fluid restriction, hyperventilation, and high-dose barbiturate therapy; 2) an ICP lower than the mean arterial pressure; and 3) a Glasgow Coma Scale (GCS) score of 8 or less on admission. The patients were divided into three groups based on computerized tomography findings: extracerebral hematoma (34 patients with subdural and/or epidural hematoma), focal cerebral lesion (20 patients with localized brain contusion and/or intracerebral hematoma), and diffuse swelling (eight patients with no focal mass lesion). Mild hypothermia prevented ICP elevation in 35 (56.5%) of the 62 patients whose ICP was greater than 20 mm Hg despite conventional therapies. Among those 35 patients whose ICP was controlled by mild hypothermia, 12 (34.3%) achieved functional recovery (good outcome or moderate disability). However, functional recovery was observed in only five (10.9%) of the 46 patients whose ICP was greater than 40 mm Hg after conventional therapies. Of 40 patients with an admission GCS score of 5 to 8, there were 11 (27.5%) who achieved functional recovery. On the contrary, mild hypothermia was not effective in 22 patients with an admission GCS score of 3 or 4. In the patients with focal cerebral lesions, ICP was controlled by mild hypothermia in 17 patients (85%) and patient outcome was intimately related to the extent of the damage. Among 18 patients with extracerebral hematoma who had a midline shift of 9 to 12 mm, raised ICP could be successfully controlled by mild hypothermia in 16 patients (88.9%) and three (16.7%) achieved functional recovery. However, ICP could not be controlled in patients with extracerebral hematoma who had a midline shift of 13 mm or more. In patients with diffuse swelling, ICP elevation could not be prevented at all by mild hypothermia. CONCLUSIONS: The authors conclude that mild hypothermia is effective for preventing ICP elevation in patients without diffuse brain swelling in whom ICP remains higher than 20 mm Hg but less than 40 mm Hg after conventional therapies.

Adolescent↗
PubMed1997

Asymmetrical regulation of blood pressure in the rat medulla.

The effects of microinjection of serotonin-1 (5-HT1) antagonist methiothepin and 5-HT1 agonist buspirone into the nucleus reticularis parvocellularis were investigated in the anaesthetized rats. Methiothepin produced an increase in arterial blood pressure when injected into the left side, but it did a decrease when injected into the right side. On the contrary, buspirone produced a decrease in arterial blood pressure when injected into the left side, but it did an increase when injected into the right side. These findings provide the clue to clarify that there is a reciprocal regulation of arterial blood pressure between the left and right sides in the rat medulla.

Animals↗
PubMed1997

Paradoxical positive nitrogen balance in burn patients receiving high-dose administration of insulin for nutritional care.

BACKGROUND: Nitrogen balance in patients who need high-dose administration of insulin has not been evaluated clinically. The purpose of this study was to compare the difference in nitrogen balance between burn patients who received high-dose administration of insulin and those who did not. METHODS: This study was performed in 19 severely burned adults with no liver or kidney failure. Patients were divided into two groups on the basis of the mean ratio of administered insulin and calorie intake (I/C) for the initial 4 weeks, a high I/C group (n = 9) and a low I/C group (n = 10). There were no significant differences between the two groups regarding age, percentage of area burned, and body weight. Nitrogen balance, blood urea nitrogen, and urine urea nitrogen were measured in all patients. Plasma concentrations of glucose, insulin, glucagon, cortisol, and urinary excretion of 3-methyl-histidine were measured in 12 patients (six in each group). RESULTS: Until day 10 both groups exhibited similar changes in plasma concentrations of glucose, insulin, glucagon, and cortisol. Subsequently, plasma concentrations of insulin and glucagon began to decrease in the low I/C group, whereas a high level was sustained in the high I/C group (p < 0.05). Plasma glucose and cortisol measurements showed no significant differences between the two groups. Blood urea nitrogen levels and urinary excretion of 3-methyl-histidine were not different between the two groups. Urine urea nitrogen excretion in the high I/C group, however, was significantly lower than that in the low I/C group from day 8 (p < 0.05). Thus the high I/C group achieved positive nitrogen balance more quickly than the low I/C group. Paradoxically, however, the high I/C group was at higher risk of septic complications and exhibited higher mortality than the low I/C group (p < 0.05). CONCLUSIONS: These results indicate that an improvement in nitrogen balance, which is accepted as a good thing in the management of critically ill patients, is not necessarily good in the high I/C group and that residual nitrogen was retained within the body in the high I/C group.

Adult↗
PubMed1997

[Effect of tea extracts, catechin and caffeine against type-I allergic reaction].

The antiallergic effects of green tea, oolong tea, and black tea extracts by hot water were examined. These extracts inhibited the passive cutaneous anaphylaxis (PCA) reaction of rat after oral administration. Three tea catechins, (--)-epigallocatechin (EGC), (--)-epicatechin gallate (ECg), and (--)-epigallocatechin gallate (EGCg) isolated from green tea showed stronger inhibitory effects than that of a green tea extract on the PCA reaction. The inhibitory effects of EGC and EGCg on the PCA reaction were greater than that of ECg. Caffeine also showed a inhibitory effect on the PCA reaction. These results indicate that tea could provide a significant protection against the type-I allergic reaction. These findings also suggest that tea catechins and caffeine play an important role in having an inhibitory effect on the type-I allergic reaction.

Administration, Oral↗
PubMed1995

Differences in body temperature changes during dressing change in surviving and non-surviving burned patients.

Change in body temperature (delta BT) while dressings were being changed was measured in 52 extensively burned adults. The patients were divided into four groups based on outcome and the prognostic burn index (PBI; age + burn index): group I (15 survivors, PBI less than or equal to 80), group II (15 survivors, PBI between 80 and 120), group III (14 non-survivors, PBI between 80 and 120), and group IV (eight non-survivors, PBI greater than 120). The body temperature before the change of dressings was the same in the four groups. The mean(s.d.) delta BT in all patients was -0.5(0.8) degrees C. The magnitude of delta BT was not related to the time required for changing dressings (r = 0.04) or to the non-epithelialized area present at each change of dressings (r = -0.05). All groups showed a similar increase in delta BT during the early period after the burn, but in group I it began to decrease progressively after the 16th day after the burn (P < 0.05). A reduction in delta BT was noted in group II from day 25, whereas it was unchanged in groups III and IV (P < 0.05). It also significantly increased 2 days before the diagnosis of sepsis (P < 0.05). These results emphasize that delta BT may provide useful information about prognosis and the development of sepsis.

Adult↗
PubMed1995

Low oxygen extraction despite high oxygen delivery causes low oxygen consumption in patients with burns recovering slowly from operative hypothermia.

BACKGROUND: Patients with burns who eventually succumbed to their injuries tended to recover more slowly from operative hypothermia than those who survived. Slower recovery was associated with a lower postoperative oxygen consumption (VO2). We have now investigated whether this was due to impairment of oxygen delivery or extraction. METHODS: This study was performed in 13 adult patients with severely burns. One hundred four measurements of VO2 by indirect calorimetry were made during recovery from 23 episodes of operative hypothermia in 11 patients. Sixty-six measurements of oxygen transport variables by balloon-tipped pulmonary artery catheter were made after 17 episodes of operative hypothermia in six patients. Body temperature was monitored in the urinary bladder. RESULTS: The rate of temperature rise (T) showed a strong positive correlation with VO2 measured both by indirect calorimetry (r = 0.91, p < 0.001) and by balloon-tipped pulmonary artery catheter (r = 0.83, p < 0.001). Oxygen delivery (DO2) was above normal in nearly all patients. Oxygen extraction was low in patients recovering slowly (T < 1.0 degree C/hr) and high in those recovering quickly (T > or = 1.0 degree C/hr). During fast recovery VO2 (373 +/- 77 ml.min-1.m-2; mean +/- SD) was approximately three times normal and was independent of DO2. In contrast, a strong linear relationship existed between VO2 and DO2 during slow recovery (r = 0.76, p < 0.001). CONCLUSIONS: Patients with burns with slow recovery from operative hypothermia exhibited impaired oxygen extraction and dependence of VO2 on DO2 over a wide range. This picture resembles that in patients with critical illness.

Adult↗
PubMed1995

[Immunologic alterations after splenectomy for trauma].

The effects of splenectomy for trauma patients on immunologic function were studied. Various immunologic indices including humoral and cellular immunity were serially measured up to one year in thirteen adult patients with blunt trauma: All the patients recovered from the initial injury and were good health at 12 month except for one died at ten month from unrelated cause. Complements and immunoglobulins decreased following splenectomy, then rapidly increased to normal or above normal levels and maintained the level throughout the one year period. Contrary to previous reports, Ig-M levels were not decreased after splenectomy. Anti-pneumococcal antibody (Pn-ab) was below effective concentration at one year except one case. Lymphocyte subpopulation was characterized by decreased T (OKT-3) cells and inverted helper/suppressor ratio. Lymphocyte blast formation was suppressed before surgery and remained low throughout the period. This study demonstrated that the humoral immunity was reserved after splenectomy, while cellular immunity such as helper/suppressor ratio and lymphocyte blast formation was impaired even one year after injury in most patients. Increased Ig-M levels after splenectomy in this study might suggest different immune response in Japanese. Decreased Pn-ab would justify the use of anti-pneumococcal vaccine after splenectomy for trauma.

Accidents, Traffic↗
PubMed1994

Fulminant hepatitis following exposure to dichlorohydrin--report of two cases.

A 34-year-old man suffered from fulminant hepatitis after cleaning a tank in which there were traces of dichlorohydrin. In spite of daily plasma exchanges, he died 10 days after exposure. A 27-year-old man with much lighter exposure showed only slight liver dysfunction. This is the first report of lethal injury following exposure to dichlorohydrin.

Adult↗
PubMed1993

Recovery from postoperative hypothermia predicts survival in extensively burned patients.

To clarify the cause of postoperative hypothermia in extensively burned patients, factors affecting postoperative hypothermia were studied in 16 extensively burned adult patients (8 survivors and 8 nonsurvivors) with a burn index greater than 35. Body temperature was monitored continuously in either the urinary bladder or rectum. Hypothermia of less than 35 degrees C occurred in 89% (66 of 74) of the total operations performed in these 16 patients. The rate of temperature rise (RTR) was significantly lower in nonsurvivors (0.4 +/- 0.2 degrees C/h) than in survivors (1.7 +/- 0.9 degrees C/h; p < 0.001). Continuous indirect calorimetry performed in seven patients (four survivors and three nonsurvivors) demonstrated that RTR was determined primarily by heat production. The measured energy expenditure reached only 1.7 +/- 0.2 times the basal energy expenditure during rewarming in nonsurvivors, whereas it was 2.7 +/- 0.9 times the basal energy expenditure in survivors (p < 0.01). Surprisingly, in nonsurvivors, the RTR was significantly decreased even during the first 2 weeks. These findings suggest that those who cannot generate heat well in postoperative hypothermia are unable to produce the additional energy required to overcome sepsis.

Adult↗
PubMed1993

Transient and repetitive rises in blood pressure synchronized with plasma catecholamine increases after head injury. Report of two cases.

The authors report two patients with repetitive episodes of acute transient rise in blood pressure synchronized with increases in plasma catecholamine after severe head injury. In both cases, the paroxysmal hypertension occurred suddenly on the 2nd day posttrauma, and its frequency declined gradually, disappearing with time. The pathophysiological basis of this peculiar clinical manifestation is discussed.

Brain Injuries↗
PubMed1993

Effect of mild hypothermia on uncontrollable intracranial hypertension after severe head injury.

Recent experimental studies have demonstrated that mild hypothermia at about 34 degrees C can be effective in the control of intracranial hypertension. A randomized controlled study of mild hypothermia was carried out in 33 severely head-injured patients. All patients fulfilled the following criteria: 1) persistent intracranial pressure (ICP) greater than 20 mm Hg despite fluid restriction, hyperventilation, and high-dose barbiturate therapy; 2) an ICP lower than the mean arterial blood pressure; and 3) a Glasgow Coma Scale score of 8 or less. The patients were divided into two groups: one received mild hypothermia (16 patients) and one served as a control group (17 patients). Mild hypothermia significantly reduced the ICP and increased the cerebral perfusion pressure. Eight patients (50%) in the hypothermia group and three (18%) in the control group survived (p < 0.05), while five (31%) in the hypothermia group and 12 (71%) in the control group died of uncontrollable intracranial hypertension (p < 0.05). In five patients in the hypothermia group, cerebral blood flow was measured by the hydrogen clearance method and arteriojugular venous oxygen difference was evaluated before and during mild hypothermia. Mild hypothermia significantly decreased the cerebral blood flow, arteriojugular venous oxygen difference, and cerebral metabolic rate of oxygen (p < 0.01). The results of this preliminary investigation suggest that mild hypothermia is a safe and effective method to control traumatic intracranial hypertension and to improve mortality and morbidity rates.

Adult↗
PubMed1992

Interaction of alpha subunit of GTP-binding protein Go with a 20-kDa Triton-insoluble membrane protein in bovine brain.

Heterotrimeric Go bound to the membranes of bovine brain, but Go alpha remained bound to the membranes even after activation with GTP gamma S. Furthermore, Go alpha bound to a Triton X-100-insoluble fraction of the membranes in a saturable manner. However, the 37-kDa Go alpha eliminated by trypsin at the amino-terminus could not bind to the fraction. Using a blot overlay approach of the Triton-insoluble fraction, only a 20-kDa protein was identified that interacts with Go alpha. These results indicate that Go alpha binds to a 20-kDa Triton-insoluble protein in the bovine brain membranes.

Animals↗
PubMed1985

[Clinicopathological study of minute cancer of the stomach].

Nineteen patients with solitary minute carcinoma (single cases) and 16 with foci of minute cancer, found as a component of multiple early gastric carcinoma (multiple cases) were studied. The results were as follows; 1) The histological type of the single cases was the differentiated type in 95%. 2) All lesions of the multiple cases were mucosal invasive carcinoma, while 16% of the single cases (3/19) had submucosal invasive carcinoma. 3) As for the distribution of the single and multiple cases according to the surrounding mucosal atrophy, the single eases were in the pyloric gland zone, the multiple cases in the intermediate zone.

Adenocarcinoma↗