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K Amakawa

Publications and source records attributed to K Amakawa.

16 recordsLinked to original sources
PubMed2001

Eotaxin and monocyte chemoattractant protein-1 in chronic eosinophilic pneumonia.

Chronic eosinophilic pneumonia (CEP) is characterized by chronic or recurrent pulmonary infiltrates with eosinophils, but the precise mechanism of eosinophil accumulation has not been fully elucidated. Eotaxin is one of the CC chemokines that selectively recruits eosinophils and contributes to the pathogenesis of allergic airway diseases including asthma, but its roles in pathogenesis of CEP have not been fully elucidated. The authors measured concentrations of eotaxin and other CC chemokines, monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T-cell expressed and secreted, macrophage inflammatory protein-1alpha, and the eosinophil activating Th2 cytokine interleukin (IL)-5 in bronchoalveolar lavage (BAL) fluid from CEP patients (n=11), and compared these concentrations with those from control subjects (n = 6). The eotaxin (904 +/- 203 versus 29 +/- 7 pg x mL(-1), p = 0.0001), MCP-1 (194 +/- 57 versus 15 +/- 2 pg x mL(-1), p < 0.05), and IL-5 (7.8 +/- 2.0 versus 2.7 +/- 0.6 pg x mL(-1), p < 0.05) levels were significantly higher for cases with CEP in comparison to those serving as controls. Proportions of eosinophil and lymphocyte counts were greater in BAL fluid from CEP patients. Eotaxin and IL-5 levels correlated with the proportion of eosinophils in BAL fluid from CEP patients. MCP-1 correlated with the relative lymphocyte numbers. In short, eotaxin, interleukin-5, and monocyte chemoattractant protein-1 levels were higher in the BAL fluid of CEP patients and these levels may contribute to eosinophil and lymphocyte recruitment and activation in the airways as found with this disorder.

Adult↗
PubMed2001

BAL induces an increase in peripheral blood neutrophils and cytokine levels in healthy volunteers and patients with pneumonia.

STUDY OBJECTIVES: To examine the peripheral effects of BAL on the neutrophil counts and cytokine levels in the circulation. DESIGN AND METHODS: WBC counts and plasma cytokines were measured before and 4 h after fiberoptic bronchoscopy (FOB) without further interventions (n = 6), or combined with BAL in normal volunteer subjects (n = 6), and in patients with bacterial pneumonia (n = 4). The bronchus of the right middle lobe was wedged, and three 50-mL aliquots of sterile saline solution was instilled. There was no endotoxin contamination in the saline solution or the fluid obtained through the working channel of bronchoscope. RESULTS: In volunteers, peripheral WBC counts and the number of nonsegmented and segmented neutrophils increased after the BAL procedure (p < 0.05) associated with the increase in plasma concentration (mean +/- SEM) of interleukin (IL)-6 (0.99 +/- 0.32 pg/mL before BAL and 20.38 +/- 13.42 pg/mL after BAL; p < 0.05) and granulocyte colony-stimulating factor (G-CSF; 14.1 +/- 1.7 pg/mL before BAL and 38.5 +/- 9.7 pg/mL after BAL; p < 0.05). The increase in WBC counts and neutrophil counts was positively correlated to the increase in IL-6 (p < 0.05) and the increase in G-CSF (p < 0.05). In patients with pneumonia, IL-6 and G-CSF levels were higher after BAL than in normal volunteer subjects (p < 0.05). There was no increase in plasma concentration of IL-1beta, tumor necrosis factor-alpha, or IL-8 after BAL in normal volunteer subjects or in patients with pneumonia. FOB without BAL did not increase the WBC count, neutrophil count, or plasma cytokine levels. CONCLUSION: The BAL procedure increases the number of WBCs, and segmented and nonsegmented neutrophils in the peripheral circulation as well as circulating IL-6 and G-CSF levels.

Adult↗
PubMed2000

Longitudinal follow-up study of smoking-induced lung density changes by high-resolution computed tomography.

To evaluate the ability of high-resolution computed tomography (HRCT) to detect longitudinal changes in structural abnormalities caused by smoking, HRCT and pulmonary function tests were used to examine nonsmokers, current smokers, and past smokers annually for 5 yr. Inspiratory HRCT was taken for the upper, middle, and lower lung fields, while expiratory images were obtained for the upper and lower lung fields only. We estimated the three quantitative CT parameters including MLD (mean CT value), HIST (CT value with the most frequent appearance), and %LAA (relative area of low attenuation with CT values less than -912 HU). Most of the pulmonary function tests, excepting FEV(1), did not change annually, whereas many of the inspiratory HRCT parameters did. In nonsmokers, only %LAA in the middle or lower lung fields exhibited an annual increase. In current smokers, %LAA in the upper lung field was augmented, while inspiratory MLD or HIST in the middle or lower lung field became more positive. In past smokers, %LAA in any lung field examined increased. The annual change in %LAA in the upper lung field was larger for past smokers than nonsmokers, with little difference between past and current smokers. Expiratory CT parameters showed few annual changes in all groups. In conclusion, (1) aging increases airspace abnormalities, mainly in the lower lung field; (2) although continuous smoking worsens airspace abnormalities mainly in the upper portion of the lung, this trend does not seem to slow down even after smoking cessation; and (3) inspiratory HRCT images are superior to expiratory images for longitudinal estimation of structural abnormalities caused by aging and smoking.

Aging↗
PubMed1998

[Placement of self-expanding metallic stents in the stenotic trachea and bronchus under the support of gas exchange by extracorporeal lung assist (ECLA)].

Three self-expanding metallic stents (MS) were placed in a patient with severe dyspnea due to tracheo-bronchial stenosis caused by a large metastatic malignant tumor. To ensure adequate gas exchange, we used ECLA during surgery. After ECLA was started with V-V bypass (blood flow 1.3 l.min-1, 100% O2 flow 10 l.min-1), the patient was administered droperidol and fentanyl, and orotracheally intubated with an endotracheal tube (7.0 mm ID) using a bronchofiberscope. Anesthesia was maintained with midazolam, but no neuromuscular blocking agent was used. The pulmonary ventilation was withheld 3 times during each period of 5-10 min for MS placement through the endotracheal tube. The patient was ventilated for a few min between each procedure. Values of arterial blood gas were maintained within physiological ranges throughout the surgery. ECLA was a useful means of ensuring adequate gas exchange in perioperative patients with difficult airway.

Adolescent↗
PubMed1996

Effects of pre- and postischemic administration of thiopental on transmitter amino acid release and histologic outcome in gerbils.

BACKGROUND: The mechanism by which barbiturates protect neurons against ischemia is unclear, particularly when they are given after ischemia or reperfusion begins. Because an excess release of excitatory neurotransmitters causes postsynaptic membrane depolarization, which triggers neuronal damage in ischemia, the effects of thiopental on histologic outcome, ischemia-induced amino acid release, and anoxic depolarization in gerbils were studied. METHODS: The effects of different doses of thiopental administered before or after ischemia were examined morphologically by assessing delayed neuronal death in hippocampal CA1 pyramidal cells produced by forebrain ischemia for 3 min in gerbils. The ischemia-induced changes in output of aspartate, glutamate, glycine, taurine, and gamma-aminobutyric acid were measured using a microdialysis-high-performance liquid chromatography procedure, and the differences among a halothane-anesthetized group, a thiopental-administered group, and a group given thiopental after a period of ischemia were evaluated. The changes induced in the direct-current potential in the hippocampal CA1 area by forebrain ischemia were compared in animals anesthetized with halothane and those given thiopental. RESULTS: Preischemic administration of thiopental at all doses decreased the risks for delayed neuronal death (P < 0.01). Post-ischemic administration at a dosage of 2 mg.kg-1.min-1 for 60 min protected neurons, but the same dose for 10 min did not ameliorate the cell injury. Forebrain ischemia produced marked increases in all amino acids 3 to 6 min after the start of recirculation in the halothane-anesthetized gerbils, whereas thiopental anesthesia (2 mg.kg-1.min-1) reduced these increases throughout the experimental period, except for glycine (P < 0.01). The initiation of thiopental after reflow did not markedly diminish these increases. Thiopental anesthesia prolonged the onset of anoxic depolarization and reduced its maximal amplitude. CONCLUSIONS: Thiopental helps protect the brain from ischemia, although treatment with this agent after ischemia requires a larger dose than that before ischemia. The effect of preischemic treatment may be related to the suppression of the excitatory amino acid release and the direct-current potential shift.

Animals↗
PubMed1996

[Mouth mask method for fiberoptic tracheal intubation in difficult intubations].

We tried 72 fiberoptic tracheal intubations (FTI) using a mouth mask in difficult intubation cases. In this method, ventilation is performed via only the mouth using a mask applied over the mouth (mouth mask) and FTI can be done via a nostril with no hindrance from the mask in anesthetized patients. We have been using an infant or child type Seal Mask (Gibeck Respiration) for the mouth mask or a specially made mouth mask. An oral airway is usually inserted and the nostril of one side is plugged with cotton. FTI is performed by another anesthesiologist. An endotracheal (ET) tube capped with a rubber diaphragm is passed through another nostril, and a fiberscope is inserted through the ET tube. The subsequent technique is the same as that of the usual FTI for awake patients. Intubations were successful in all cases except 2; in one, ventilation was impaired even with oral airway in place, and in the other, bleeding in upper airway due to jaw injury from traffic accident hindered the sight of the scope. Mouth mask method for FTI is safe, useful and practical in difficult intubations with little discomfort to the patient.

Adolescent↗
PubMed1995

[The histological changes in the spinal cord following percutaneous cervical cordotomy (PCC) and correlation of these changes with the efficacy of PCC].

We observed the histological changes in the spinal cord following percutaneous cervical cordotomy (PCC) and correlation of these changes with the efficacy of PCC in 7 cases. A fine monopolar electrode which we used, measured 0.25 mm or 0.27 mm in diameter with exposed length of 2 mm. An oval or elliptical-shaped lesion, 1 to 3 mm in width and 3 to 4 mm in length, was observed in 6 of these cases. The main lesion was found in the anterolateral column in 5 cases. In 3 of these 5 cases, the whole anterolateral column had been destroyed, and in the other 2 cases dorsal one half to two thirds of it had been destroyed. In these 5 cases, pain sensation on the opposite side of PCC was lost for a long time and pain was relieved until death (21-239 days after PCC). In the other 2 cases the lesion in the anterolateral column was tenuous or unrecognizable, and the loss of pain sensation was temporary with pain recurring by the next day. This study showed that an oval or elliptical-shaped lesion was made in PCC and that in cases in which main lesion was located in the anterolateral column, pain relief was long lasting.

Adult↗
PubMed1995

[The efficacy of intravenous lidocaine on various types of neuropathic pain].

We examined the efficacy of systemic local anesthetics on various types of neuropathic pain in 89 patients. Lidocaine 1.5 mg.kg-1 was infused intravenously for one minute. Pain score (PS) by visual analogue scale (VAS, 0-10) was measured 1, 5, 15 and 35 min after the infusion. The efficacy of intravenous lidocaine was evaluated by PS which was lowest after infusion. PS decreased to less than 50 percent of pre-infusion value in more than 75 percent of cases of cancer pain, postherpetic neuralgia, trigeminal neuralgia, low back pain with signs of root pain or spinal canal stenosis, peripheral nerve injury and thalamic pain, in 50-75 percent of cases of herpetic neuralgia, and in less than 50 percent of cases of cervical spondylosis, spinal cord injury, reflex sympathetic dystrophy, causalgia and psychogenic pain. This study suggests that systemic local anesthetics is effective in neuropathy due to cancer pain, postherpetic neuralgia, trigeminal neuralgia, low back pain with signs of root pain or spinal canal stenosis, peripheral nerve injury and thalamic pain.

Aged↗
PubMed1994

[Classification of post-cordotomy dysesthesia].

Postcordotomy dysesthesia was classified from the clinical features of dysesthesia following percutaneous cervical cordotomy (PCC) in 66 patients. Dysesthesia occurred in 10 (15.2%) of 66 patients and was classified into three types. In the first type, dysesthesia occurred at the region where pain had been before PCC, and pain sensitivity had been lost due to PCC. This type of dysesthesia occurred in 6 patients. In this type, the peripheral nerve damage caused by tumor invasion was presumably the cause of dysesthesia. In the second type, dysesthesia occurred all over the region where pain sensitivity had been lost due to PCC. This type of dysesthesia occurred in 2 patients. The destruction of second order neurons of the nociceptive pathway by PCC was presumably the cause of this type of dysesthesia. In the third type, dysesthesia occurred at the region where pain had been before PCC and pain sensitivity had partially recovered. This type of dysesthesia occurred in 3 patients. The reduction of the effect of PCC was presumably the cause of this type of dysesthesia.

Adolescent↗
PubMed1992

Dynamic aspects of AMPs in the kidney in physiological conditions--their metabolism and turnover.

The past few decades have witnessed a number of studies on AMPs in the kidney. Almost all of these studies, however, have dealt with the quantitative and qualitative analysis of AMPs in the kidney using biochemical techniques, whereas the dynamic aspect of AMPs in the kidney has been overlooked and its metabolism and turnover have never been emphasized. On the other hand, the kidneys removed from humans and experimental animals revealed a wide variety in interstitial tissue in the medulla microscopically and in the papilla of the kidney macroscopically. The reasons for these variations in the medulla, its mechanism and the matrical component have not yet been clarified. In an effort to clarify these points, we herein describe our study on the dynamic aspect of AMPs in kidney histologically in relation to their biological turnover which we employed several staining methods. Our results revealed that there was a very active turnover of AMPs present in the kidney confirming that the kidney plays an important role physiologically in AMP metabolism. The degree of the turnover of AMPs in the kidney varies from case to case. In the active phase, AMPs are excreted in the glomerulus and reabsorbed in the proximal portion of the collecting tubules. Most of the absorbed AMPs are finally drained through the lymphatic vessels in situ and a few are excreted into the urine. Contrary cases have been demonstrated, however, only were a few AMPs were noted throughout the nephrons in the kidney. AMP turnover in the kidney is unexpectedly remarkable. The medulla, which has been considered less important, in fact, plays a key role in AMP metabolism.

Alcian Blue↗
PubMed1992

[Optimal pH and PaCO2 during moderate hypothermia].

Effects of pH and PaCO2 on cerebral as well as systemic hemodynamics and oxygen consumption were investigated during moderate hypothermia under 0.5% halothane anesthesia. Twenty-seven adult mongrel dogs were cooled to 28 degrees C (brain temperature) with a surface cooling method. They were divided into 3 groups, pH-stat (pH 7.35 n = 9), alpha-stat (pH 7.48 n = 9), and alkalosis (pH 7.70 n = 9). During hypothermia cardiac index fell to 74%, 56%, and 45%, and cerebral blood flow to 54%, 42%, and 36% in pH-stat, alpha-stat and alkalosis groups, respectively. Cerebral and systemic oxygen consumptions decreased to approximately 54% and 47%, respectively in all groups. Cerebrospinal fluid pH rose from 7.36 precooling to 7.49 (pH-stat), 7.53 (alpha-stat), and 7.72 (alkalosis). We concluded from these results that pH-stat and alpha-stat management have no significant effect on either hemodynamics or metabolism during moderate hypothermia but alkalosis management has deleterious effects because of the alkalinity itself and of the hyperventilation by which the alkalosis is induced.

Animals↗
PubMed1985

Responsiveness of cerebral vessels to changes of blood pressure and partial pressure of carbon dioxide after a transient period of cardiac arrest in dogs.

Post-ischemic cerebral hypoperfusion supposedly due to constriction of cerebral vessels is considered to be one of the most important factors limiting the recovery of the brain after cerebral ischemia. An experimental study on dogs was carried out to determine the changes in the responsiveness of cerebral vessel to the dilating effects of increase of arterial pressure (AP) and of CO2 inhalation after 3-6 min of cardiac arrest. Responsiveness was measured by the ratio of change in intracranial pressure (ICP) to change in AP (delta ICP/delta AP) and to change in PCO2 (delta ICP/delta PCO2), since in a bony cranium the changes in cerebral vessel diameter are reflected by instantaneous ICP change. delta ICP/delta AP following the administration of intravenous epinephrine was 33%, 43%, 36%, 37% and 16% of pre-ischemic value 1 h, 2 h, 3 h, 4 h and 5 h after cerebral ischemia, respectively. delta ICP/delta PCO2 following 10% CO2 inhalation was 13%, 32%, 55%, 50%, 70% and 75% of pre-ischemic value 1/2 h, 1 h, 2 h, 3 h, 4 h and 5 h after cerebral ischemia, respectively. Normal delta ICP/central venous pressure (delta CVP) was observed during the post-ischemic period, although statistical analysis was not done. From this we concluded: After 3-6 min of cardiac arrest, cerebral arteries constricted for more than 5 h during post-ischemic period. These arteries did not respond well to the dilating effects of increased arterial pressure or CO2 inhalation, but after 3 h their responses to CO2 inhalation returned to their pre-ischemic levels. The intracranial pressure became more or less dependent on CVP during post-ischemic period.

Animals↗