A Multimodal Sensing Device for Simultaneous Measurement of Dissolved Oxygen and Hydrogen Ions by Monolithic Integration of FET-Based Sensors.

We examined the possibility of measuring dissolved oxygen by using a potentiometric solid-state semiconductor sensor. Thin films of tin (IV) oxide (SnO2) are widely used in oxygen gas sensors. However, their ability to detect dissolved oxygen (DO) in solutions is still unknown. In this paper, we present a method for investigating the dissolved oxygen-sensing properties of SnO2 thin films in solutions by fabricating a SnO2-gate field-effect transistor (FET). A similarly structured hydrogen ion-sensitive silicon nitride (Si3N4)-gate FET was fabricated using the same method. The transfer characteristics and sensitivities were experimentally obtained and compared. The transfer characteristics of the FET show a shift in threshold voltage in response to a decrease in DO concentration. The SnO2-gate FET exhibited a sensitivity of 4 mV/ppm, whereas the Si3N4-gate FET showed no response to DO. Although the SnO2-gate FET responds to pH changes in the solution, this sensitivity issue can be eliminated by using a Si3N4-gate FET, which is capable of selectively sensing hydrogen ions without DO sensitivity. The experimental results indicate the promising properties of SnO2 thin films for multimodal sensing applications.

Hearing Outcomes and Complications of Cochlear Implantation in Elderly Patients over 75 Years of Age.

OBJECTIVE: Populations are aging in many countries, and the proportion of elderly people with severe to profound hearing loss is increasing in parallel with the increasing average life span. The objective of this study was to investigate the outcomes of cochlear implant (CI) surgery in elderly patients compared to those in younger patients. METHODS: The outcomes of CI surgery were retrospectively investigated for 81 adults (32 men and 49 women) who underwent CI surgery at our hospital. They were divided according to age at the time of implantation into the younger group (<75 years of age; n = 49) or elderly group (≥75 years of age; n = 32). RESULTS: The mean sentence recognition score on the CI-2004 Japanese open-set test battery (±standard deviation) was 82.9% ± 24.1 in the younger group and 81.9% ± 23.2 in the elderly group, with no significant difference between the groups (Mann-Whitney U test). The incidence of major complications that required surgical treatment was not significantly different between the groups (4.1% vs. 6.2%, respectively). Thus, there were no severe complications that could affect general health status in either group. Three patients in each group died for reasons unrelated to CI surgery during follow-up. The proportion of patients who were alive and continued to use the CI five years after surgery was 92.8% and 91.5%, respectively. CONCLUSION: Our results show good speech recognition and a low incidence of major complications in elderly patients. This comprehensive report on the outcomes of CI surgery in elderly patients will be helpful to the elderly with severe to profound hearing loss when deciding whether to undergo CI surgery.

[Cytotoxicity of antiglaucoma ophthalmic solutions for human corneal endothelial cells].

PURPOSE: The cytotoxicity of a range of commercial antiglaucoma ophthalmic solutions was assessed in human corneal endothelial cells using in vitro techniques. METHODS: Cell survival was measured using the WST-1 assay for endothelial cells and the MTT assay for epithelial cells. Commercially available timolol, carteolol, latanoplast, unoprostone, levobunolol, bunazosine, betaxolol, nipradiol, dorzolamide, brinzolamide, and pilocarpine were assessed. The survival of cells exposed to test ophthalmic solutions was expressed as a percentage of cell survival in the control solution (distilled water added to media) after 48 hours exposure. RESULTS: Survival was lower in prostagrandines and in medications containing benzalkonium. It increased to more than 85% after dilution of 1000-fold or more dilution. CONCLUSIONS: Antiglaucoma ophthalmic solutions have corneal endothelial toxicity. The toxicity significantly decreases after dilution of 1000-fold or more dilution and toxicity seems to be due mostly to benzalkonium chloride.

The effect of G-CSF in a myocardial ischemia reperfusion model rat.

PURPOSE: It has been reported that G-CSF administration improves cardiac function by reducing the area of the infarct in a myocardial infarction model rat. In the present study, myocardial infarction model rats, produced by ligation of the left anterior coronary artery, were prepared. The G-CSF effect for treating cardiac muscle cell disorders by ischemia reperfusion was studied. METHODS: Myocardial infarction model rats were produced by ligation of the left anterior descending coronary artery in 12-week-old Wistar rats. G-CSF was administered subcutaneously daily at a dose of 100 microg/kg/day for 5 days to rats with a complete ligation (MI-G group, n=6) and rats in which the ligated coronary artery was reperfused 30 minutes after the ligation (R-G group, n=6). Physiological saline was subcutaneously administered to rats with a complete ligation and reperfusion (MI-C and R-C groups, respectively, n=6 each), as controls. After 4 weeks, the infarct area ratio (%), cardiac function on echocardiography (left ventricular ejection fraction), and a myocardial histopathological diagnosis were carried out and the results compared among the groups. RESULTS: No significant differences were found in the proportion of the residual heart muscle in the infarct lesion, myocardial wall thickness, or left ventricular ejection fraction between the MI-G and MI-C groups. In contrast, the infarct area, myocardial wall thickness, and left ventricular ejection fraction were significantly improved in the R-G group compared to the R-C group (p<0.05). CONCLUSIONS: Any inhibitory effect of G-CSF on the infarct lesion was found in the myocardial infarction reperfusion model rat, but only a small effect was found in rats with a complete ligation-induced myocardial infarction. The findings in the present study, therefore, suggest that G-CSF is effective for treating cardiac muscle cell disorders by ischemia reperfusion.

Foldable acrylic intraocular lens with distended haptics for transscleral fixation.

We describe a foldable acrylic intraocular lens (IOL) with distended haptics suitable for transscleral fixation and the insertion procedure. The IOL has an acrylic optic and poly(methyl methacrylate) haptics with a microscopic indentation 1.3 mm from the tip. Transscleral fixation of the IOL was performed through corneal incisions in 22 eyes, and surgical results were retrospectively assessed. The IOL was sutured firmly in position using the cow-hitch procedure, and there was no suture loosening to the distended haptic. The IOL design provided suitable fixation and may be indicated for bag fixation as well as transscleral fixation.

Clinical study on the effects of nizatidine on gastric motility and cardiac autonomic function. Investigations using electrogastrography and spectral analysis of heart rate variability.

Nizatidine (CAS 76963-41-2, Acinon), an H2 receptor antagonist, not only inhibits acid secretion but also improves gastrointestinal motility. However, autonomic nervous function has not been studied in detail using electrogastrography (EGG). In the present study, two protocols were adopted to study nizatidine's effects on cardiac autonomic function and gastric motility. Protocol I--Acute: "Group C-I": 10 healthy volunteers received a single oral dose of nizatidine 150 mg. Protocol II--Chronic: "Group DM without N": 15 patients with diabetes mellitus (DM) were observed prior to administration of nizatidine. "Group DM with N": The same 15 patients with DM received nizatidine 300 mg/day for more than 30 days. "Group C-II": This control group was composed of 15 healthy volunteers not receiving nizatidine. In all groups, EGGs were recorded before and after a meal, and autonomic nervous function and QT interval of ECG dispersions were simultaneously evaluated. In Group C-I, nizatidine significantly increased the peak power amplitude of 3 cycles/min (cpm) frequency, but did not significantly change the dominant frequency of the 3-cpm waves. In Group DM with N, nizatidine administration significantly increased the peak power amplitude from 2.4 cpm or a lower frequency (bradygastria) to 3 cpm. Prior to nizatidine administration but after eating a meal, the peak power amplitude on EGG was not increased in Group DM without N. In Group DM with N, however, the EGG peak power amplitude increased to levels similar to those of the healthy subjects (Group C-II). Neither the single nor the chronic administration of nizatidine significantly prolonged the QT interval or increased the QT dispersion. A spectral analysis of heart rate variability showed that nizatidine administration, whether acute or chronic, did not significantly change the indices of autonomic nervous activity. Nizatidine may promote gastric emptying by inhibiting acetylcholine esterase, thus increasing cholinergic activity, and by acting directly on gastric smooth muscle. The results indicate that because nizatidine increases gastric motility without exerting a negative influence on the autonomic nerves, it may be a useful drug in patients with diabetic neuropathy.