Biomedical subjects

Tetsu Nemoto

Publications and source records attributed to Tetsu Nemoto.

6 recordsLinked to original sources

PubMed2006

Real-time monitoring of respiration rhythm and pulse rate during sleep.

A noninvasive and unconstrained real-time method to detect the respiration rhythm and pulse rate during sleep is presented. By employing the a trous algorithm of the wavelet transformation (WT), the respiration rhythm and pulse rate can be monitored in real-time from a pressure signal acquired with a pressure sensor placed under a pillow. The waveform for respiration rhythm detection is derived from the 26 scale approximation, while that for pulse rate detection is synthesized by combining the 2(4) and 2(5) scale details. To minimize the latency in data processing and realize the highest real-time performance, the respiration rhythm and pulse rate are estimated by using waveforms directly derived from the WT approximation and detail components without the reconstruction procedure. This method is evaluated with data collected from 13 healthy subjects. By comparing with detections from finger photoelectric plethysmograms used for pulse rate detection, the sensitivity and positive predictivity were 99.17% and 98.53%, respectively. Similarly, for respiration rhythm, compared with detections from nasal thermistor signals, results were 95.63% and 95.42%, respectively. This study suggests that the proposed method is promising to be used in a respiration rhythm and pulse rate monitor for real-time monitoring of sleep-related diseases during sleep.

Adult↗

PubMed2005

Radiotelemetry recording of electroencephalogram in piglets during rest.

A wireless recording system was developed to study the electroencephalogram (EEG) in unrestrained, male Landrace piglets. Under general anesthesia, ball-tipped silver/silver chloride electrodes for EEG recording were implanted onto the dura matter of the parietal and frontal cortex of the piglets. A pair of miniature preamplifiers and transmitters was then mounted on the surface of the skull. To examine whether other bioelectrical activities interfere with the EEG measurements, an electrocardiogram (ECG) or electromyogram (EMG) of the neck was simultaneously recorded with the EEG. Next, wire electrodes for recording movement of the eyelid were implanted with EEG electrodes, and EEG and eyelid movements were simultaneously measured. Power spectral analysis using a Fast Fourier Transformation (FFT) algorithm indicates that EEG was successfully recorded in unrestrained piglets, at rest, during the daytime in the absence of interference from ECG, EMG or eyelid movements. These data indicate the feasibility of using our radiotelemetry system for measurement of EEG under these conditions.

Animals↗

PubMed2005

A novel stereotaxic approach to the hypothalamus for the use of push-pull perfusion cannula in Holstein calves.

To determine secretory patterns of growth hormone-releasing hormone (GHRH) and somatostatin (SS) and their roles in the regulation of growth hormone (GH) secretion, a method for collecting hypothalamic perfusates, a push-pull perfusion method was developed in calves. With the use of the stereotaxic apparatus for cattle, a cannula was implanted into the hypothalamus of four male calves based upon cerebral ventriculography. Push-pull perfusates were collected at 10 min intervals for 6h and GHRH and SS concentrations in perfusates and plasma GH concentration were determined by EIAs and RIA, respectively. A cannula was implanted into the hypothalamus based on the image of the third ventricle and maintained for 1 month. GHRH and SS showed pulsatile secretion and the pulses for GHRH and SS were irregular in conscious animals. Neither GHRH nor SS secretion had a clear relationship with GH secretion. In the present study, we thus (1) established a stereotaxic technique for approaching the hypothalamus using cerebral ventriculography for calves, and (2) demonstrated that GHRH and SS secretion were pulsatile but not closely related to GH profile in conscious calves. The technique is useful for the study of the functions of the hypothalamus in the control of pituitary hormones in cattle.

Animals↗

PubMed2005

Intraocular pressure lowering effect of brinzolamide 1.0% as adjunctive therapy to latanoprost 0.005% in patients with open angle glaucoma or ocular hypertension: an uncontrolled, open-label study.

PURPOSE: A prospective study was conducted to evaluate the intraocular pressure (IOP) lowering effect of brinzolamide 1.0% ophthalmic suspension as an adjunctive therapy with latanoprost 0.005% ophthalmic solution in patients with open angle glaucoma or ocular hypertension. PATIENTS AND METHODS: Fourteen patients with open angle glaucoma (OAG) or ocular hypertension (OH) who had been using latanoprost 0.005% for more than 6 months were initiated on adjunctive brinzolamide therapy. The IOP values at 1 month, 2 months, and 3 months were compared with those measured immediately before adding brinzolamide to the regimen (baseline). The incidence of adverse events such as conjunctival hyperemia and corneal epithelial defect were also examined. RESULTS: The baseline IOP was 21.1 +/- 4.8 mmHg (mean +/- standard deviation). After 1 month, 2 months, and 3 months of therapy IOP was 16.9 +/- 4.5 mmHg, 16.6 +/- 4.0 mmHg, and 15.9 +/- 3.1 mmHg, respectively, showing significant reductions in IOP at all the measuring time-points during the study compared with the baseline value (p < 0.01). Conjunctival hyperemia developed in one patient after 1 month and in another after 2 months; however, both were mild, and therapy was continued. Corneal epithelium defect was observed in 3 patients. One of them had mild defect before brinzolamide was added to the regimen. Increase of eye discharge was seen in one patient. No serious side effects were otherwise observed. CONCLUSION: The addition of brinzolamide to a latanoprost 0.005% regimen may further lower intraocular pressure in patients with open angle glaucoma or ocular hypertension.

Aged↗

PubMed2004

A computer image processing system for quantification of zebrafish behavior.

The tropical zebrafish (Danio rerio) has frequently been used for investigating developmental biology. Here, we developed a computer image processing system for quantifying zebrafish behavior. We could acquire an image of zebrafish freely moving in an aquarium using a CCD camera through a graphic I/O board. To acquire the image of moving zebrafish in real time, we required high spatial (256 x 256 pixels) and temporal (10 frames/s) resolution. Such a high speed of data analysis was accomplished using a skipping search method. By using a small aquarium, trackings of newborn zebrafish could be traced. The velocity of adult zebrafish (7.2 cm/s) was far faster than that of newborn zebrafish (1.8 cm/s). Furthermore, by separation of occluded images of two fish, we could acquire images of the two zebrafish. They behaved as in a school in which one fish chased the other. The chasing was defined by the distance, angle and approach of the two fishes. The chasing ratio of pairs of zebrafish was 37%, whereas those of pairs of different fish were significantly reduced to less than 20%. The present image processing system is a very useful tool for quantitatively scoring the schooling behavior of multiple fish.

Animals↗

PubMed2004

Development of a stereotaxic instrument for study of the bovine central nervous system.

We have developed a bovine stereotaxic instrument in this study to be used for Holstein cattle from weanling to adult age. The bovine stereotaxic instrument is derived from the Horsley-Clarke principle. A pair of straight ear-bars and orbital ridge pieces with their carriers, head clamps, AP bars are symmetrically arranged across the head pace. For holding the heavy heads, a hard palate and a mandibular support are designed to be placed on the surface of the base frame. A new manipulator with long working distance has also been made. For ventriculography, a holder inserting an X-ray film cassette is placed just next to the AP bar. Finally, the instrument was combined together with an oil-operated lift, so that it can be adjusted to a proper height. Details of this instrument are described in this paper.

Animals↗