Non-contact acquisition of brain function using a time-extracted compact camera.

A revolution in functional brain imaging techniques is in progress in the field of neurosciences. Optical imaging techniques, such as high-density diffuse optical tomography (HD-DOT), in which source-detector pairs of probes are placed on subjects' heads, provide better portability than conventional functional magnetic resonance imaging (fMRI) equipment. However, these techniques remain costly and can only acquire images at up to a few measurements per square centimetre, even when multiple detector probes are employed. In this study, we demonstrate functional brain imaging using a compact and affordable setup that employs nanosecond-order pulsed ordinary laser diodes and a time-extracted image sensor with superimposition capture of scattered components. Our technique can simply and easily attain a high density of measurement points without requiring probes to be attached, and can directly capture two-dimensional functional brain images. We have demonstrated brain activity imaging using a phantom that mimics the optical properties of an adult human head, and with a human subject, have measured cognitive brain activation while the subject is solving simple arithmetical tasks.

Interference phase-contrast imaging technology without beam separation.

Interferometers are widely used in science and industry to measure small displacements, changes in refractive index, and surface irregularities. In all interferometers, including phase-contrast microscopes and DICs (differential interference contrast microscopes), light from a single source is split into two beams that travel along different optical paths. They are then recombined to produce interference. The fundamental operation of beam separation makes device configuration more complex and adds to the bulk of the equipment. In this study we propose a new method of observing phase-contrast images without beam separation by using self-interference inside a grating coupler structure disposed on the observation plane. We experimentally demonstrate that the self-interference principle can generate phase-contrast images using a simple configuration. From measurements using a multilevel phase plate, we confirm its phase-contrast depth resolution to approach one- tenth of a wavelength.

A patient with schizophrenia presenting with post-lobotomy catatonia treated with olanzapine: a case report.

A 79-year-old Japanese woman with schizophrenia was hospitalized because of idiopathic duodenal stenosis. Three days after discontinuing ingestion, including the administration of psychotropic drugs, the patient demonstrated incoherent behaviour and strong general muscle tension, and was unable to engage in conversation. Computed tomography indicated bilateral regions of low density in the frontal lobes, subsequent to which she was diagnosed with post-lobotomy catatonia. Administration of olanzapine (10 mg/day) improved the patient's condition within a short period. Previous studies have demonstrated an association between the dysfunction of frontal circuits and catatonia; therefore, the observed catatonic episode might relate to the disconnection of nerve fibres in the prefrontal lobes induced by her lobotomy. Olanzapine was likely effective in treating catatonia because of its reported efficacy in improving frontal lobe function.

Clinical evaluation of percutaneous endoscopic gastrostomy tube feeding in Japanese patients with dementia.

AIM: The aim of this study was to clinically evaluate percutaneous endoscopic gastrostomy (PEG) tube feeding of elderly Japanese patients with dementia. METHOD: The records of the 155 patients with dementia who underwent PEG in Juntendo Tokyo Koto Geriatric Medical Center were reviewed for pertinent clinical data, including diagnosis of dementia, place of stay before and after hospitalization, as well as survival rate, albumin levels, and incidence of aspiration pneumonia (AP) before and 6 months after PEG feeding. The latter three data of these patients were compared with those of 106 patients with dementia fed through a nasogastric (NG) tube. RESULTS: Alzheimer's disease and vascular dementia were predominant. Fifty-three percent of the patients were admitted from their home; the number of discharges to homes decreased to 21.2%. The mean (SD) of the albumin levels was 2.9 (0.4) g/dl before feeding and 2.9 (0.6) g/dl after 6 months. Among the patients with AP before PEG tube feeding, 51.6% had an AP recurrence. Conversely, AP occurred in 9.4% of the patients without AP before feeding. The patient survival rate was higher by 27 months when using PEG tube than when using an NG tube. CONCLUSION: PEG tube feeding in patients with dementia leads to preservation of status for a few years. Compared with NG tube feeding, PEG tube feeding did not induce AP due to impairment of intact swallowing function, and was associated with higher survival rate of approximately 2 years. However, PEG tube feeding does not seem to promote home medical care.

Investigation of crystallization and amorphization dynamics of phase-change thin films by subnanosecond laser pulses.

We report experimental results on amorphization and crystallization dynamics of reversible phase-change (PC) thin-film samples, GeSbTe and GeBiTe, for optical disk data storage. The investigation was conducted with subnanosecond laser pulses using a pump-and-probe configuration. Amorphization of the crystalline films could be achieved with a single subnanosecond laser pulse; the amorphization dynamics follow closely the temperature kinetics induced in the irradiated spot. As for crystallization of the samples initially in the amorphous state, a single subnanosecond pulse was found to be insufficient to fully crystallize the irradiated spot, but we could crystallize the PC film (in the area under the focused spot) by applying multiple short pulses. Our multipulse studies reveal that the GeSbTe crystallization is dominated by the growth of nuclei whose initial formation is slow but, once formed, their subsequent growth (under a sequence of subnanosecond pulses) happens quickly. In the case of GeBiTe samples, the crystalline nuclei appear to be present in the material initially, as they grow immediately upon illumination with laser pulses. Whereas our amorphous GeSbTe samples required approximately 200 pulses for full crystallization, for the GeBiTe samples approximately 15 pulses sufficed.

T-cell malignant lymphoma of the ileum causing ileac fistulas: report of a case.

We herein present a rare case of three fistulas caused by a recurrence of T-cell lymphoma of the ileum. A 67-year-old man presented at a local hospital with left lower abdominal pain in May 1997. Upper and lower gastrointestinal examinations did not reveal any abnormal findings, but an abdominal aortic aneurysm was diagnosed by computed tomography, and thus was determined to be the source of the pain. The patient was referred to our hospital to undergo a grafting operation; however, a laparotomy performed in July 1997 revealed an unexpected small intestinal tumor, and therefore a partial ileectomy between 15 and 70cm in an oral direction from the terminal ileum was carried out instead. Histopathological and genetic examinations demonstrated diffuse small malignant lymphocytic T-cell lymphomas of the ileum invading all layers. Metastasis of the facial skin and local recurrence were recognized 5 months later, and chemotherapy with THP-COP and ESHAP only resulted in progressive disease. An ileac fistula was found to have formed between the intestine and abdominal wall in March 1998, and the patient died in May 1998. An autopsy revealed three fistulas caused by metastatic tumors, one of which communicated with the duodenum from the ileum, one with the skin from the ileum, and one to the transverse colon from the ileum.