Histogenesis of congenital and acquired melanocytic nevi based on histological study of lesion size and thickness.

The histogenesis of melanocytic nevi is poorly understood. It is important to determine the differences and similarities in histogenesis between congenital and acquired nevi. To clarify the histogenic differences between acquired melanocytic nevi (AMN) and congenital melanocytic nevi (CMN), diameter and depth of nevus cells (tumor thickness) were examined in histological specimens from 80 cases of CMN and 71 cases of AMN, and these nevi were classified according to Mark's pathological CMN criteria. In all cases, giant CMN nevus cells were found in the lower marginal portion of excised specimens. The mean diameter and lesional thickness were significantly higher in CMN than in AMN. AMN diameter showed a significant correlation (r = 0.567, P < 0.05) with lesional thickness, while no such relation was observed in CMN. In addition, a significant correlation between lesion diameter and thickness was observed in small (<10 mm) non-Mark's type CMN (r = 0.626, P < 0.05). CMN may be classified into three subtypes: (i) caused by increased proliferation of melanoblasts during the course of migration from the neural crest to the epidermis; (ii) proliferation of nevus cells after arrival at the epidermis, and nevus cell distribution affected by adnexa and dermal differentiation; and (iii) arising after completion of skin development before birth.

Influence of outdoor activity and indoor activity on cognition decline: use of an infrared sensor to measure activity.

OBJECTIVE: The increasing number of dementia patients causes serious social problems. Previously, we reported that elderly individuals with cognitive impairment show a low frequency of activity. This study was designed to investigate the correlation of daily activity to the decline in cognitive function. METHODS: The study enrolled 53 elderly who live alone. The cognitive function of subjects was assessed by the mini-mental state examination (MMSE) before the investigation. Passive infrared sensors were installed in the subjects' houses. The subjects' in-house movements were recorded by the sensors for approximately 1 year. The activities of daily life were assessed, based on these records. The subjects' cognitive function was assessed again after the investigation and categorized into two groups: the cognition decline group (MMSE score: <24, n=6) and the normal group (MMSE score: over 24, n=44). The activity parameters were compared between the two groups. RESULTS: The subjects in the cognition decline group had a significantly lower number of outings (8.8 vs. 17.3, p<0.01) and there was no cognition decline in patients in the frequent outings group (over 20 outings per month). In addition, the indoor movement decreased in the cognition decline group during the study period and the indoor movement of the normal group was maintained at the baseline level. CONCLUSIONS: This study objectively evaluated the behavior of elderly individuals with infrared sensors and revealed that elderly people who have few occasions to go out tend to show a decrease in cognitive function.

Degeneration of the locus ceruleus noradrenergic neurons in the stress-induced depression of rats.

We produced a model of depression in rats which have been exposed to 2-weeks forced walking stress. Electron microscopic observation on the locus ceruleus (LC) cells of the model rats disclosed low dense areas, destroyed membranes, aggregation of intracellular organs, and increased microglia. Density of LC axon terminals in the frontal cortex stained with dopamine beta-hydroxylase antiserum and percentage of LC cells stained with horseradish peroxidase or activated by electrical stimulation antidromically were low in the model. These indices increased in the model treated with imipramine. These findings suggest that the LC noradrenergic neurons degenerate in depression, but regenerate in remission.

Distribution of telemedicine in Japan.

This paper reports the situation of telemedicine in Japan. A comprehensive database search showed that a total of 1,006 telemedicine projects had been implemented from 1997 to 2004. Teleradiology accounted for the largest proportion (37%) of these projects and home-care telemedicine (home telecare) accounted for one third of the total number of projects. The subsequent questionnaire-based survey revealed that 348 projects were active in 2004, indicating a more than twofold increase in the number of ongoing projects from the 151 projects reported in 1997. In particular, the use of home telecare and telepathology has exhibited an approximately fourfold increase since 1997. Telemedicine was most common in remote areas, although approximately 30% of the projects were implemented within urban areas. The number of telemedicine projects peaked twice: in municipalities with populations ranging from 10,000 to 30,000 and in municipalities with populations ranging from 100,000 to 300,000. However, with regard to the population density, there was no characteristic distribution of implementation. The present data suggest that in Japan, there are various population sizes and densities for which telemedicine may be valuable.

New approach for the early detection of dementia by recording in-house activities.

People with dementia often have low physical activity and some sleep problems. This study focused on daily life activities and sleeping conditions, and examined the use of these parameters for detecting dementia. Five passive infrared (IR) sensors were installed in each of 14 subject's houses. Each patient lived alone. The subjects' in-house movements were recorded by the passive IR sensor for approximately 3 months (average, 78 days). Based on these records, the following parameters of life activities were assessed: (1) the number of outings, (2) total sleep time, (3) number of sleep interruptions, and (4) sleep rhythm. Subjects with impaired cognition (Mini Mental State Examination [MMSE] < 24) had a significantly lesser number of outings (p = 0.001) and a tendency toward a shorter sleep time (p = 0.054) in comparison with control subjects (MMSE >or= 24). These results suggest that the monitoring of life activities by using passive infrared sensors could be an efficient method for detecting dementia.

Eye contact in medical examinations using videophones.

In Japan, approximately 12,000,000 cellular phones with a videophone function have been distributed and are becoming an important part of the telemedicine infrastructure. By eye movement analysis, we investigated the effectiveness of eye contact using cellular videophones during medical interviews. Three male volunteers acted as first-time patients and were filmed using a high-resolution camera. The video of each of these volunteers was converted into pictures of three different sizes-70 cm x 40 cm (large picture), 26 cm x 20 cm (medium picture), and 14 cm x 12 cm (small picture)-and viewed on a 32-inch video monitor. The large, medium, and small pictures were considered to represent an actual medical interview, an interview via a television conference system, and an interview via a cellular videophone, respectively. Nine doctors watched these pictures, and their eye movements were recorded with a gaze-point recorder. After watching the videos, the doctors evaluated quality of three size pictures. Standard deviation values of the gaze point coordinates decreased with the picture size. However, a very low decrease was observed in the time ratio, during which the gaze point was on the face (eye contact rate); the rate was 92.2% (large picture), 91.8% (medium picture), and 85.1% (small picture). No statistical difference was observed between the values of the medium and small pictures. Subjective evaluations yielded low scores in the small pictures. The relatively high rate of eye contact rate in the small pictures suggests that a cellular videophone will be a good tool for telemedicine, although the usage by which the subjective evaluations can be improved should be determined by doctors.

Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan.

OBJECTIVE: To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma. DESIGN: Multicenter, retrospective study. SETTING: University hospitals in Japan. PATIENTS: Patients with melanocytic lesions on acral volar skin. A total of 712 melanocytic lesions (103 malignant melanomas, including 36 in situ lesions, and 609 melanocytic nevi) were consecutively collected from the files of 3 hospitals. Diagnoses of all the lesions had been determined histopathologically. INTERVENTIONS: Dermoscopic examination. MAIN OUTCOME MEASURES: The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the major dermoscopic patterns seen in benign and malignant melanocytic lesions on acral volar skin. RESULTS: The parallel ridge pattern and irregular diffuse pigmentation showed extremely high specificity (99.0% and 96.6%, respectively) and very high negative predictive value (97.7% and 97.5%, respectively) in malignant melanoma. For melanoma in situ, the positive predictive value and diagnostic accuracy of the parallel ridge pattern were significantly higher than those of irregular diffuse pigmentation (P = .009 and P = .006, respectively). In melanocytic nevi, the specificity and positive predictive value of the parallel furrow pattern and/or the latticelike pattern were found to be very high (93.2% and 98.3%, respectively). CONCLUSIONS: Dermoscopy is immensely helpful in differentiating malignant melanomas from melanocytic nevi on acral volar skin. Moreover, the parallel ridge pattern aids in detecting acral melanomas in early, curable stages.

Number of acquired melanocytic nevi in patients with melanoma and control subjects in Japan: Nevus count is a significant risk factor for nonacral melanoma but not for acral melanoma.

BACKGROUND: Epidemiologic studies have suggested that number of acquired melanocytic nevi is a risk factor for melanoma development in Japanese as it is in white populations. However, there are only a few population-based studies on acquired nevi in Asian populations, and no epidemiologic study on relationship between number of acquired nevi and melanoma in Japanese populations has been reported. OBJECTIVE: The purpose of this study was to assess number, size, and distribution of acquired melanocytic nevi in a Japanese population. Particular attention was paid to evaluation of relationship between number of acquired nevi and development of nonacral or acral malignant melanoma. METHODS: In all, 82 patients with malignant melanoma and 600 control subjects were included in this study. All participants were Japanese. The number of acquired melanocytic nevi, 2 mm or larger in diameter, on the whole body except the scalp and genital areas was counted by experienced dermatologists. The participants were divided into 5 age categories (0-19, 20-39, 40-59, 60-79, and >80 years old) for the statistical analyses. This categorization adjusted the age and sex distribution between patients with melanomas and control subjects in 40- to 59-, 60- to 79-, and over 80-year-old groups. RESULTS: In the control Japanese population, the number of acquired melanocytic nevi on the whole body increased with age in 0- to 19-year-old age group and reached the highest number, 6.7 +/- 8.1/person, in 20- to 39-year-old group. In patients with nonacral melanoma, the number of acquired nevi on the whole body in 40- to 59- and 60- to 79-year-old groups was significantly higher than that of the corresponding control group. In contrast, the rate of individuals who had acquired nevi on soles, palms, and nail apparatus was not significantly different between acral melanoma group and the control group in 40- to 59- and 60- to 79-year-old groups. CONCLUSION: This study has revealed that a large number of acquired melanocytic nevi is a risk factor for the development of nonacral melanoma in Japanese and white populations. However, acquired nevi on soles, palms, and nail apparatus do not seem to be a risk factor for acral melanoma in Japanese populations.

Contribution of the stress-induced degeneration of the locus coeruleus noradrenergic neurons to the pathophysiology of depression: a study on an animal model.

A novel theory on the pathophysiology of depression would be expected to resolve a contradiction between therapeutic time lag and monoamine hypothesis. On the basis of the fact that a subgroup of depression appears during or after stress, we exposed rats to a long-term (2 weeks) forced walking stress and produced depression-model rats in one group and spontaneous recovery rats in another. The density of axon terminals of the locus coeruleus (LC) neurons in the frontal cortex stained by dopamine ß-hydroxylase antiserum was lower in the depression-model rats than in the spontaneous recovery rats and in the control rats without stress. The density was higher in the model rats daily treated with imipramine than in those treated with saline. Morphological projection (MP) index (a percentage of horseradish peroxidase-positive LC cells in total number of LC cells) and electrophysiological projection index (a percentage of LC neurons activated antidromically by electrical stimulation of the cerebral cortex) were lower in the depression-model rats than in the recovery and control rats. MP index was higher in the imipramine-treated rats than that in the saline-treated rats. Electron microscopic examination of the LC disclosed such degenerative changes as low-dense areas without structure, aggregation of intracellular organs, destroyed membranes around the rough endoplasmic reticulum (rER), a decreased number of deformed subsurface cisterns, glia invaginated into the LC neurons and prominent appearance of microglia containing increased number of lipofustin or lysosome in the model rats, but not in the spontaneous recovery rats. These findings suggest that the terminals and cell bodies of the LC noradrenergic neurons degenerate in the stress-induced depression-model rats and regenerate in the imipramine-treated model rats. This degenerative change may possibly contribute to the decrease in synthesis and metabolism of noradrenaline (NA), the slowing of axonal flow, the accumulation of NA in the neurons, the decrease in discharge rate of LC neurons without stress and the increase in release of NA in response to an additional stress. It may also explain the therapeutic time lag that is required to repair the noradrenergic neurons.

Realtime ultrasound screening by satellite telecommunication.

Realtime ultrasound screening was carried out using a medical examination vehicle equipped with a diagnostic ultrasound scanner and a satellite telecommunication system. Screening was performed on 205 residents in a rural community in Japan and consisted of 57 cardiac, 57 abdominal, 60 thyroid and 31 breast ultrasound scans. The resolution of the realtime ultrasound images sent via communications satellite at 1.5 Mbit/s was almost identical to that of the original images taken by the ultrasound scanner. A disorder was diagnosed in 11 (19%) of the cardiac examinations, 28 (49%) of the abdominal, 19 (32%) of the thyroid and 7 (23%) of the breast examinations. Although some technical problems occurred, ultrasound screening by telemedicine appears to be a promising technique for those who live in rural communities.

[Inter-hospital teledermatology conference using a videophone network].

We organized an inter-hospital teledermatology conference with images through a digital telephone line (ISDN, 128kbps). Our conference system consists of two videophones. A videophone "Phoenix PICSEND-R" (NTT) in the multi-point connection mode is used for discussion among doctors from five hospitals. In addition, using another videophone "Phoenix mini type-S" (NTT), clinical and dermoscopic findings obtained with a digital video camera and a videomicroscope "VMS-1900" (Scalar, Tokyo) respectively were transmitted to Shinshu University Hospital from four rural sites. We have found that the quality of the images obtained is entirely sufficient to make an accurate diagnosis. To calibrate the color and size of skin lesions, a matching sticker "CASMATCH" (Bearmedic, Tokyo) has proved useful. Forty-one times of conference were held from September 1999 to August 2002. In total, the concordance rate between the telediagnosis and the finally confirmed diagnosis was 69% (77 of 112 cases). In cases limited to pigmented skin lesions, the rate was higher (84%) and it was concluded that such conditions are suited for the telediagnosis. The ease with which the data can be manipulated enables us to discuss difficult cases in detail. This style of teleconference system may have benefits for dermatologists especially at rural hospitals in consultation with senior doctors.

[Medical support for Belarus after Chernobyl accident using a telemedicine system].

To achieve a close relationship among Gomel Regional Hospital (Gomel, Belarus), Belarusian Children Center of Hematology/Oncology (Minsk, Belarus) and Shinshu University Hospital, we established a telemedicine system using the Inmarsat satellite. The system consists of a TV conference system, a digital microscopic imaging system and a high-definition image server/viewer network system (DICOM). The detailed case conference is possible among three areas of physicians.

[Mobile hospital -real time mobile telehealthcare system with ultrasound and CT van using high-speed satellite communication-].

A real-time telescreening system is developed to detect early diseases for rural area residents using two types of mobile vans with a portable satellite station. The system consists of a satellite communication system with 1.5Mbps of the JCSAT-1B satellite, a spiral CT van, an ultrasound imaging van with two video conference system, a DICOM server and a multicast communication unit. The video image and examination image data are transmitted from the van to hospitals and the university simultaneously. Physician in the hospital observes and interprets exam images from the van and watches the video images of the position of ultrasound transducer on screenee in the van. After the observation images, physician explains a results of the examination by the video conference system. Seventy lung CT screening and 203 ultrasound screening were done from March to June 2002. The trial of this real time screening suggested that rural residents are given better healthcare without visit to the hospital. And it will open the gateway to reduce the medical cost and medical divide between city area and rural area.

Telemedicine of the heart: real-time telescreening of echocardiography using satellite telecommunication.

The early detection of disease is important to keep people healthy, but it is not easy for elderly residents living in rural areas at a distance from well-equipped medical institutes to be examined. Therefore, the present study evaluated the usefulness of real-time telescreening of echocardiography using satellite communications. The participants in this study were 57 residents of a rural community in Japan. The resolution of the real-time ultrasound images sent by communications satellite was almost identical to that of the original images taken in the hospital. Although some problems remain to be solved, telescreening of echocardiography will be a practical method for public health in the near future.

[Telemedicine support system in home care of patients with chronic respiratory failure: preliminary results].

We report the preliminary results of an advanced telemedicine system for the delivery of home care services. We have been trying out a system for a ternary telemedicine network for remote consultation in patients with chronic respiratory failure. The elements of this system are: the patients at home, the home doctor (and/or community hospital), and an institution with respiratory staff (Shinshu University), which were linked by ISDN lines. The system allows real-time visualization, at home, of the patients and their physiological data, which are transmitted simultaneously to both the community hospital and Shinshu University. Respiratory specialists can advise the home doctor on the treatment and follow-up evaluations of distant patients. We consider that the telemedicine network system has the potential to improve clinical outcomes and to provide home care services to patients with chronic health conditions.