Search PubMed⌕ Search

Biomedical subjects

H Kato

Publications and source records attributed to H Kato.

At least 253 records · Page 14Linked to original sources

[The effects of conscious sedation by propofol on respiration during abdominal hysterectomy under spinal anesthesia].

The effects of conscious sedation by propofol on respiration were studied in 28 patients undergoing abdominal hysterectomy under spinal anesthesia. The patients were randomly assigned to receive conscious sedation by propofol (Group P, n = 20) or no sedation (Group C, n = 8). After a satisfactory level of analgesia had been achieved, a loading dose of propofol, 0.2 mg.kg-1 was administered every minute in Group P until patients exhibited spontaneous eye closure or nystagmus. Thereafter, the infusion rates were adjusted to maintain conscious sedation. Respiratory rate, SpO2 and nasal PETCO2 were measured every minute during the initial 30 minutes and subsequently at 5-min intervals. The patients were questioned on the 1st postoperative day concerning intraoperative recall and the level of satisfaction. The mean loading dose of propofol was 0.4 mg.kg-1 and the mean mainteinance rate was 1.7 +/- 0.5 mg.kg-1.h-1. Compared with Group C, the respiratory depression was less in Group P; SpO2 was significantly higher at 25 min after spinal tap and PETCO2 was significantly lower at 30 and 50 min after spinal tap in Group P. A score of patient satisfaction was significantly higher in Group P. Conscious sedation by propofol is a safe and useful supplement to spinal anesthesia for abdominal hysterectomy.

Adult↗

[Lymph node dissection in lung cancer].

The standard surgical treatment for stage I, II, and IIIa non-small cell lung cancer (NSCLC) is lobectomy with mediastinal lymph node dissection. In our series of 214 patients with N2 disease the 5-year survival rate was 23%. Systematic mediastinal lymph node dissection provides further prognostic information on the N factor. Among NSCLC patients with a pathological diagnosis of N2, there are significant differences in the 5-year survival rate based the 3 factors of clinical N factor, N1 station metastasis, and N2 station metastasis.

Adult↗

Hypermethylation of p16(INK4a) and p15(INK4b) genes in non-small cell lung cancer.

Hypermethylation of CpG island is a common mechanism by which tumor suppressor genes are inactivated. The tumor suppressor genes p16(INK4a) and p15(INK4b) are important components of the cell cycles. We have studied the feasibility of detecting tumor-associated aberrant p16(INK4a) and p15(INK4b) methylation in non-small cell lung cancer (NSCLC) using methylation-specific PCR. We found a high frequency of hypermethylation of the p16(INK4a) gene in 17 of 45 cases of NSCLC. In this study, there was no difference between the clinicopathological features or overall survival of patients with and without p16(INK4a) methylation. On the other hand, p15(INK4b) promoter hypermethylation is rare (5/45) in lung cancer and occurs in association with p16(INK4a) methylation. The overall survival of patients with p15(INK4b) methylation was markedly shortened in this series. We also analyzed cells in bronchial washings, and p16(INK4a) methylation was detected in 4 of 17 cases of NSCLC. Moreover, 1 of 10 plasma samples from patients with NSCLC was positive for p16(INK4a) methylation. Our results suggest a possible prognostic role of p15(INK4b) methylation in NSCLC, and that the detection of aberrant p16(INK4a) methylation in both bronchial washings and plasma may be useful for cancer diagnosis.

Adult↗

Effects of a highly toxic coplanar polychlorinated biphenyl, 3,3',4,4',5-pentachlorobiphenyl on intermediary metabolism: reduced triose phosphate content in rat liver cytosol.

The effects of a highly toxic coplanar polychlorinated biphenyl, 3,3',4,4',5-pentachlorobiphenyl (PenCB), on triose phosphate metabolizing enzymes were studied. Male Wistar rats received 25 mg/kg PenCB, i.p. At this dose the compound provokes a wasting syndrome. The activity of triose phosphate metabolizing enzymes, glyceraldehyde-3-phosphate dehydrogenase, triose phosphate isomerase, glycerokinase, transaldolase and transketolase were significantly reduced by PenCB treatment to 50%, 60%, 50%, 70% and 40% of free-fed controls, respectively. An inhibition study with pyrazol, a specific inhibitor of alcohol dehydrogenase (ADH), showed that ADH makes about a 30% contribution to the formation of glycerol-3-phosphate from glyceraldehyde-3-phosphate. Our current study revealed that PenCB suppresses ADH at the protein expression level. The reduced formation of glycerol-3-phosphate from glyceraldehyde dehydrogenase by PenCB could be due to the suppression of ADH. The triose phosphate content in the liver cytosol of PenCB-treated rats was significantly lower than in free-fed controls. The suppression of triose phosphate metabolism could be a cause of the wasting syndrome provoked by highly toxic coplanar PCB.

Animals↗

[Reevaluation of the surgical indications for lung cancer based on the N factor].

The Standard surgical treatment for stage I, II, and IIIa non-small cell lung cancer (NSCLC) is lobectomy with systemic mediastinal lymph node dissection. More than 50% of our series of 220 patients with cN2 disease were classified as pN0-1. The postoperative 5-year survival rate of patients with cN2 disease was 36%, and that of those with cN2-pN2 disease was 18%. Tumor cell type, surgical technique, or site of tumor had no prognostic significance, although pN, cT, and number of N2 sites were of prognostic significance. We conclude that the indications for surgery are T1-2 N2 disease with a single N2 site.

Adenocarcinoma↗

Supracostal approach--an excellent exposure for renal and adrenal surgery.

The supracostal extraperitoneal and extrapleural approach provides wide exposure during renal and adrenal operations without damaging the neurovascular bundles and spares the partial resection of rib. We performed renal and adrenal operations on 33 patients by this approach. The procedures were accomplished smoothly obtaining a broad surgical field without costal resection. Complications were rare and postoperative pain seemed to be mild. Hence, the supracostal approach is considered as a better method with excellent exposure to the kidney and adrenal and is anatomically comprehensive.

Adenoma↗

[A new technique to preserve the larynx in surgery for cervical esophageal carcinoma and the limit of its practical application].

A new technique to preserve the larynx in esophagectomy for cervical esophageal carcinoma is described. The trachea, which prevents exposure of the cervical esophagus, is dissected while maintaining the continuity of the recurrent laryngeal nerve. The tracheal stumps were turned over like a double door, and the esophageal tumor is excised with sufficient margins for suturing. The cervical esophagus is safely replaced with a free jejunum or the stomach followed by tracheal reconnection. The technique of tracheal reconnection in the neck is not difficult and is a safe procedure. Anastomotic insufficiency of the trachea may be compensated for with a temporary tracheostomy. This method is applicable in esophagectomy not only with curative but also with palliative intent to offer the patient a better quality of life. Theoretically, this method can be applied even for tumors minimally invading the trachea in which the invaded tracheal segment can be excised in combination with the esophagus, followed by tracheal anastomosis. Because this technique is a safe and easy procedure, it is recommended in cases in which proximal anastomosis appears difficult.

Esophageal Neoplasms↗

[Preoperative PDT for early stage lung cancer accompanied with infiltration to the central airway].

For the treatment of central type lung cancers, it is often necessary to perform bronchoplasty or bi-lobectomy even in early stage cases in which tumor invasion is found at the bronchial bifurcation. To solve this contradictory situation, we applied PDT for central type early stage lung cancer to reduce the extent of superficial infiltration, enabling a simple surgical technique or decreasing the amount of resected lung parenchyma. Among 7 patients, the simplification of surgical technique and reduction of the range of resection were possible in 2 cases each respectively. However, these objectives were not satisfied in the remaining 3 cases and the operations performed were those that had been originally scheduled before PDT. The current problems are the establishment of appropriate laser irradiation technique and accurate assessment for extension of invasion.

Adult↗

[Hand motor cortical area reorganization following cerebral infarction evaluated with functional MRI, near infrared spectroscopic imaging, and transcranial magnetic stimulation].

A 60-year-old, right-handed man suffered from left hemiparesis with upper limb dominance. CT and MRI revealed cerebral infarction of the entire right middle cerebral artery territory. His hemiparesis recovered excellently and residual neurological deficits 6 years later were left hand weakness(grasping power 9 kg vs. 35 kg in the right) and clumsiness. Functional MRI was performed. During right(normal) hand grasping, activation was seen in the left sensorimotor cortex and supplementary motor area. During left(paretic) hand grasping, activation was seen in the left (ipsilateral) sensorimotor cortex, right parietal cortex, and bilateral supplementary motor areas. Near infrared spectroscopic imaging showed similar results. During right hand grasping, left sensorimotor cortex was activated, and during left hand grasping, bilateral sensorimotor cortices were activated with ipsilateral predominance. Transcranial magnetic stimulation of the left motor hand area evoked right hand movement and stimulation of a point near that area evoked ipsilateral left hand muscle movement. Thus, the findings of the three techniques consistently suggest that the recovery of left hemiparesis of this patient was promoted by motor cortical area reorganization including the ipsilateral motor cortex.

Brain↗

Fluid shear stress suppresses interleukin 8 production by vascular endothelial cells.

The effects of shear stress on interleukin 8 (IL-8) production by human umbilical vein endothelial cells (HUVEC) were studied by subjecting the HUVEC to a steady flow laminar shear stress of up to 0.7 N/m(2) in a parallel plate flow chamber. Shear stress decreased IL-8 mRNA expression in a dose and time-dependent fashion. High glucose concentrations increased IL-8 mRNA levels in a MAPK-p38-dependent manner, which was suppressed by shear stress. Measurement of IL-8 protein in HUVEC culture media by ELISA demonstrated that IL-8 secretion was also increased by high glucose and suppressed by shear stress. These results suggest that the anti-atherogenic effect of shear stress arises partly from the suppression of the production of IL-8 which has been shown to trigger the adhesion of monocytes to a vascular endothelium and also acts as a mitogen and chemoattractant for vascular smooth muscle cells.

Arteriosclerosis↗

[Histopathological examination of tissues removed from the retinal surface during vitrectomy in idiopathic macular holes].

PURPOSE: We examined electron microscopically the tissues removed from the retinal surface in cases with idiopathic macular holes. MATERIALS AND METHODS: We performed vitrectomy for idiopathic macular holes in 43 eyes from June 1994 to December 1998 at Fukuoka University Chikushi Hospital. The removed tissues were evaluated with transmission electron microscope in only 8 of the 43 eyes. All cases underwent 3 port vitrectomy. After occurrence of posterior vitreous detachment, epiretinal tissues were removed around the macular hole using a micro-hook needle. RESULTS: All tissues were transparent under an operating microscope, and they curled naturally. Histopathological examination showed that the removed tissues were from 2 to 6.5 microns thick. All tissues were composed mainly of extracellular matrix. There were type 2 collagen fibers in 6 eyes and basement membrane-like structures in 2 eyes. There were few cell components. All cases had the macular hole closed by the first surgery. Four eyes had improved visual acuities of more than 2 lines. The remaining 4 eyes had the same visual acuity as before the operation. CONCLUSION: Residual vitreous on the retinal surface was the main component of the transparent tissues removed from the retinal surface during vitrectomy.

Adult↗

Inverse correlation of thioredoxin expression with estrogen receptor- and p53-dependent tumor growth in breast cancer tissues.

Estrogen receptor (ER) and p53 are important transcription factors in the growth regulation of tumor cells in breast cancer. We reported previously that thioredoxin (TRX) regulates the DNA binding activities of ER and p53 in vitro. The expression of pS-2, a trefoil factor, is also correlated with that of ER. To clarify the regulation mechanism of tumor growth in breast cancer, here we investigated the expression of TRX, ER, pS-2, and p53 and the mitotic index (MI) in 147 breast cancer tissues using immunohistochemical analysis. Of 123 TRX+ cases, ER+ cases (n = 62) showed a higher pS-2 score and lower MI than did ER- cases (n = 61). Furthermore, p53- cases (no mutation in p53; n = 76) also showed a lower MI than did p53+ cases (n = 47). There was no significant correlation between pS-2 and ER, MI and ER, or p53 and MI in the TRX- group. Among the ER+ and p53- cases (ER+/p53- group; n = 61), MI was lower in the TRX+ group (n = 46) than in the TRX- group (n = 15). However, in all other groups (n = 86) with abnormalities in the immunohistochemical expression of either p53 or ER, there was no significant correlation between MI and TRX expression. In the TRX+ and ER +/p53- group (n = 46), histological grading was lower than that in all other groups (n = 101). These findings suggest that TRX expression is linked to the ER- and p53-dependent regulation of tumor growth in breast cancer. In addition, TRX expression in ER+ and p53 intact (wild-type p53+) groups may mean better prognosis than in other conditions.

Adult↗

[The significance of neoadjuvant intra-arterial chemotherapy for locally advanced breast cancer by different methods].

For neoadjuvant intra-arterial (IA) chemotherapy in locally advanced breast cancer patients, Seldinger's methods were found to be convenient and had the same effect and outcome as conventional methods. The prognosis of the patients in whom IA chemotherapy was locally effective and had fewer than n 1 lymph node metastases was comparatively favorable. However, several patients who underwent IA chemotherapy later experienced local recurrence, and the cause of these patient's death was distant metastases in almost all cases. We recommend neoadjuvant IA and systemic chemotherapy, and systemic adjuvant chemotherapy.

Adult↗