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Hiroshi Sumida

Publications and source records attributed to Hiroshi Sumida.

7 recordsLinked to original sources
PubMed2004

Erythemas caused by electrodes while monitoring neuromuscular blockade: three cases.

Skin erythemas formed in three patients during surgery at the sites where negative electrodes had been attached to stimulate the ulnar nerve for a neuromuscular transmission monitor (Relaxograph). The patients were all women, aged 52, 62, and 74 years, and general anesthesia lasted 8 h 20 min, 4 h 50 min, and 8 h 45 min, respectively. The electrodes used were disposable ECG electrodes in the first two patients and one designed for a neuromuscular monitor in the third; all were carbon-coated and then covered with gel. However, when the electrodes were detached from the lesion, they all showed loss or damage of the carbon coating under the gel. We recommend balancing the merit of monitoring with the risk of complications, even when applying an apparently safe, noninvasive monitor.

Aged↗
PubMed2004

[Perioperative failure of hemodialysis shunts: analysis of risk factors].

BACKGROUND: Because vascular access dysfunction results in substantial morbidity in patients undergoing chronic hemodialysis, this complication should be avoided. However, we experienced four patients whose hemodialysis shunts failed within 24 hours postoperatively. METHODS: We retrospectively analyzed operations performed under general anesthesia in our hospital for patients receiving hemodialysis shunts between May 2001 and October 2002. Comparisons between cases with and without perioperative shunt failures were performed using Mann-Whitney and Fishers exact tests. RESULTS: Spinal surgery (P<0.01) and surgery placed in prone or knee-chest positions (P<0.05) were significantly more frequent, and the operation times (P<0.01) and blood losses (P<0.05) were significantly greater, in the occluded group (n=4) than in the non-occluded group (n=12). CONCLUSIONS: Prone position might have impaired venous backflow from the shunt, thus promoting thrombogenesis. Additionally, moderate hemorrhage, with or without blood transfusion, may have induced a transient hypercoagulable state during the operation, which thus contributed to the acute shunt failure.

Anesthesia, General↗
PubMed2003

Life span shortening of normal fibroblasts by overexpression of BCL-2: a result of potent increase in cell death.

It is well known that BCL-2 protects against cell death by both apoptosis and necrosis. The culture of bcl-2-transfected normal fibroblasts showed a shorter life span by about 12 population doubling levels compared to that of vector transfectants (64 vs 76 population doubling levels, respectively). An MTT assay revealed that BCL-2-overexpressing cells (HCA2/bcl-2) showed more severe growth suppression due to hydrogen peroxide or doxorubicin treatment than vector control cells (HCA2/vector). We observed a significant number of dead cells in the HCA2/bcl-2 culture, but not in the HCA2/vector culture. Other BCL-2 family proteins with both antiapoptotic and proapoptotic activity and other apoptosis-related factors were maintained at similar levels, indicating that overexpression of BCL-2 is the major reason that normal fibroblasts are sensitized to cell death. A broad caspase inhibitor (z-Val-Ala-Asp-fmk) and inhibitors of specific caspases (acetyl-Asp-Glu-Val-Asp-CHO, acetyl-Ile-Glu-Thr-Asp-CHO, and acetyl-Leu-Glu-His-Asp-CHO) suppressed cell death of HCA2/bcl-2 effectively, suggesting involvement of caspase 3-, 8-, and 9-dependent pathways in cell death and that the form of death is apoptosis. Unexpectedly, involvement of active MEK in cell death was shown by the use of its inhibitor, suggesting that crosstalk between BCL-2 and the MAP kinase cascade regulates death as well as life span.

Apoptosis↗
PubMed2002

Effect of BCL-2 down-regulation on cellular life span.

Reactive oxygen species (ROS) are toxic for cells. BCL-2 is known as the anti-death protein and acts as an antioxidant. When the BCL-2 level of normal fibroblasts was suppressed by antisense bcl-2 oligodeoxynucleotide or antisense bcl-2 RNA expression, the life span of the culture was shortened by about 11 population doublings (approx. 15% of the total life span) in comparison to the control culture. Since about twice as many cell deaths were observed in the antisense culture than in the vector culture, the life span shortening was probably caused by ROS-induced death. Acceleration of telomere shortening was not evident in the antisense culture. Other BCL-2 family proteins showed no significant change in expression. Cell death was suppressed by N-acetyl-L-cysteine, an antioxidant, suggesting that ROS were the major cause of cell death. In conclusion, reduction of BCL-2 makes cells more sensitive to death induced by ROS and leads to shortening of the culture's life span.

Antioxidants↗
PubMed2002

[Airway management in tracheal stenosis caused by malignant goiter].

We report a case of malignant goiter with severe tracheal stenosis. The patient was a 61-year-old female, who had orthopnea on admission. Radiological examinations revealed a tracheal stenosis extending from 4.5 cm to 8 cm below the glottis; the smallest caliber being 5 mm. On the seventh day after admission, the patient complained of dyspnea even while sitting. An emergency tracheotomy was scheduled. While the patient was awake in a sitting position, a fiberscope was inserted endotracheally to confirm the intact inner surface of the trachea, and then an armored endotracheal tube (outer diameter 9.2 mm, inner diameter 6.5 mm) was inserted. Unexpectedly, the tube could be advanced through the stenosis without resistance. After induction of general anesthesia, the patient was placed in a supine position, and a tracheotomy was performed. This case demonstrates that, while intubation of the trachea through a stenosis is sometimes dangerous, it may be indicated when the inner surface of the trachea is intact and a tube with an inner diameter greater than 5 mm can then be placed.

Anesthesia, General↗
PubMedDate not supplied

In utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) affects tooth development in rhesus monkeys.

We thought to validate the current tolerable daily intake (TDI) value for dioxin (4 pg/kg) in Japan. Pregnant rhesus monkeys received an initial dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 0, 30, or 300 ng/kg subcutaneously) on day 20 of gestation; the dams received additional injection of 5% of the initial dose every 30 days until day 90 after delivery. The teeth of stillborn, postnatally dead, and surviving offspring (now approximately 4 years old) were evaluated. None of the offspring in the 0 and 30 ng/kg groups (n=17 and 15, respectively) had tooth abnormalities, whereas 10 of 17 in the 300 ng/kg had them. These findings suggest the lowest-observed adverse-effect level (LOAEL) for TCDD in the rhesus monkey is between 30 and 300 ng/kg, and probably is close to that for rodents (86 ng/kg) on which the current TDI was based. It is reasonable to conclude that the current TDI needs no immediate modification.

Abnormalities, Drug-Induced↗