Iron deficiency is associated with poor prognosis in idiopathic sudden sensorineural hearing loss.

OBJECTIVE: The effects of iron deficiency on the prognosis of idiopathic sudden sensorineural hearing loss are unclear. This study aimed to investigate the association between serum iron levels and idiopathic sudden sensorineural hearing loss prognosis and its usefulness as an independent prognostic marker for idiopathic sudden sensorineural hearing loss. METHODS: The audiological and haematological data, including hearing recovery and serum iron levels, of 103 patients with idiopathic sudden sensorineural hearing loss evaluated between 2015 and 2018 were retrospectively analysed. RESULTS: The overall complete recovery rate was 16.5 per cent. Initial higher hearing threshold was associated with poor idiopathic sudden sensorineural hearing loss prognosis. Serum iron levels were significantly higher in the complete recovery group than in the non-complete recovery group (p < 0.05). CONCLUSION: The possibility of complete recovery from idiopathic sudden sensorineural hearing loss was significantly lower with lower serum iron levels, suggesting that the serum iron level might be a novel prognostic marker for idiopathic sudden sensorineural hearing loss.

Pathogenic mechanism of mouse brain damage caused by oral infection with Shiga toxin-producing Escherichia coli O157:H7.

In a previous study, we showed that infection with Shiga toxin (Stx)-producing Escherichia coli O157:H7 (strain Sm(r)N-9) caused neurologic symptoms in malnourished mice with positive immunoreactions of Stx2 in brain tissues. The present study explores the mechanism of how Stx injures the vascular endothelium to enter the central nervous system in mice. Oral infection with strain Sm(r)N-9 elicited a tumor necrosis factor alpha (TNF-alpha) response in the blood as early as 2 days after infection, while Stx was first detected at 3 days postinfection. In the brain, TNF-alpha was detected at day 3, and its quantity was increased over the next 3 days. Frozen sections of the brains from moribound mice contained high numbers of apoptotic cells. Glycolipids recognized by an anti-Gb3 monoclonal antibody were extracted from the brain, and purified Stx2 was able to bind to the glycolipids. In human umbilical vascular endothelial cells (HUVEC) cultured with fluorescein-labeled Stx2 (100 ng/ml), TNF-alpha (20 U/ml) significantly facilitated the intracellular compartmentalization of fluorescence during 24 h of incubation, suggesting the enhanced intracellular processing of Stx2. Consequently, higher levels of apoptosis in HUVEC were found at 48 h. Short-term exposure of HUVEC to Stx2 abrogated their apoptotic response to subsequent incubation with TNF-alpha alone or TNF-alpha and Stx2. In contrast, primary exposure of HUVEC to TNF-alpha followed by exposure to Stx2 alone or TNF-alpha and Stx2 induced apoptosis at the same level as obtained after 48-h incubation with these two agents. These results suggest that the rapid production of circulating TNF-alpha after infection induces a state of competence in vascular endothelial cells to undergo apoptosis, which would be finally achieved by subsequent elevation of Stx in the blood. In this synergistic action, target cells must be first exposed to TNF-alpha. Such cell injury may be a prerequisite to brain damage after infection with Stx-producing E. coli O157:H7.

Adjuvant effect of clarithromycin on chemotherapy for murine lung cancer.

Clarithromycin (CAM) increased the median survival of patients with unresectable non-small-cell lung cancer who had received chemotherapy and/or radiotherapy [Chemotherapy 1997;43:288-296]. The present study was performed to ascertain whether CAM alone exhibits an antitumor effect against Lewis lung carcinoma (LLC) and to analyze the nature of its adjuvant effect on LLC-inoculated C57BL/6 mice. CAM at 10 mg/kg/day retarded the growth of subcutaneously inoculated LLC cells; consequently, the mean survival time of mice with LLC increased. This treatment was also effective in reducing the number of tumor nodules in the lung after intravenous inoculation with LLC cells. When tumor-bearing mice received an intravenous injection of vindesine sulfate (7 mg/kg) and cisplatin (6 mg/kg) 7 days after tumor inoculation, the chemotherapeutic effect was significantly enhanced by CAM treatment when it started 7 days after chemotherapy, but not when it started the day after chemotherapy. The delayed initiation of CAM treatment resulted in the enhancement of natural killer cell activity and CD8+ T cell cytotoxicity and increased the number of interferon-gamma-producing T cells and interleukin-4-producing T cells. These findings indicate that CAM can exhibit an antitumor effect by itself and also induce the well-balanced expansion of helper T cell subsets in tumor-bearing mice recovering from the immunosuppression caused by chemotherapy. CAM may therefore be a promising adjuvant drug in anticancer chemotherapy, and treatment with this macrolide should be initiated at some interval after basic cancer therapy.

Endocrine and hemodynamic changes during liver surgery in patients with compensated liver cirrhosis.

The purpose of this study was to determine hormonal levels in compensated liver cirrhotic patients under general anesthesia before and after liver surgery. We measured plasma norepinephrine, epinephrine, arginine vasopressin, and aldosterone levels and renin activity in non-cirrhotic and compensated cirrhotic patients undergoing liver resection after induction of anesthesia but before skin incision and after the end of operation but before discontinuation of nitrous oxide. We simultaneously measured hemodynamic variables. Plasma levels of norepinephrine (P < 0.001), epinephrine (P < 0.001), arginine vasopressin (P < 0.05), renin (P < 0.05) and aldosterone (P < 0.001) significantly increased after completion of surgery compared with those before incision in both groups. There was a significant positive correlation between plasma renin and aldosterone (r = 0.56, P < 0.01) levels in non-cirrhotics, but no correlation was observed in cirrhotics; and there was a significant positive correlation between plasma norepinephrine and arginine vasopressin (r = 0.45, P < 0.05) levels in non-cirrhotics, but no correlation in cirrhotics. Cardiac index and arterial pressure increased after the end of operation (P < 0.05). This increase after the operation was the same between cirrhotic and non-cirrhotic groups. There were no changes in heart rate, mean pulmonary arterial pressure, and pulmonary capillary wedge pressure after the end of operation. We conclude that hemodynamic and endocrinological changes were similar between compensated cirrhotic patients and non-cirrhotic patients during liver surgery. Endocrine changes might partly explain the hemodynamic changes during surgery.

Effect of combined infusion of nitroglycerin and nicardipine on femoral-to-radial arterial pressure gradient after cardiopulmonary bypass.

Nitrates and calcium channel blockers are frequently administered during cardiac surgery. We simultaneously measured femoral arterial pressure and radial arterial pressure to investigate whether nitrates, in conjunction with calcium channel blockers, would influence the central-to-peripheral arterial pressure gradient. Combined nitroglycerin and nicardipine infusion during cardiac surgery involving coronary artery bypass grafting or valve replacement resulted in a significant increase above baseline levels in the femoral-to-radial arterial pressure gradient at 60 min after cardiopulmonary bypass. In control patients there was no significant increase in the femoral-to-radial arterial pressure gradient at 60 min after completion of cardiopulmonary bypass. A subsequent study in patients given nitroglycerin and nicardipine identified that the difference in the systolic arterial pressure between femoral and radial arteries was observed 15, 60, and 120 min after completion of cardiopulmonary bypass. However, there was no difference in the mean arterial pressure between femoral and radial arteries throughout the same period. We conclude that combined infusion of nitroglycerin and nicardipine, a new calcium channel blocker, intensifies the magnitude and duration of the femoral-to-radial arterial pressure gradient after cardiopulmonary bypass.

Changes in serum glucose and serum growth hormone levels during pituitary surgery.

During transsphenoidal surgery, serum growth hormone (GH) and serum glucose levels were measured in five acromegalic patients with diabetes or glucose intolerance, three acromegalic patients without diabetes or glucose intolerance, and six patients with prolactinoma. Preoperative steroid administration produced a significant increase in serum glucose level in acromegalic patients with diabetes or glucose intolerance, whereas in the other two groups no significant change in serum glucose level was found. After surgery started, there was a statistically significant increase in serum glucose level above baseline levels in all three groups. Serum GH levels decreased after commencement of surgery in acromegalic patients, and tumor manipulation did not produce a statistically significant increase in serum GH levels. Simultaneous increases in serum glucose and serum GH levels upon tumor manipulation did not occur in any group. We conclude that preoperative steroid administration in patients with high serum levels of GH in association with diabetes or glucose intolerance increases serum glucose levels, and that, after commencement of surgery, GH has only a minor role in the changes of serum glucose levels.