Experimental Model of Asthma by Toluene Diisocyanate (TDI)

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。Attention has been paid to respiratory hypersensitivity in workers who are exposed to toluene diisocyanate (TDI) in their workshops. An experimental model of asthma in guinea pigs by TDI has been developed. A 10% TDI solution dissolved in ethyl acetate was painted on the nasal cavities of guinea pigs with a thin cotton applicator once daily for five consecutive days. Three weeks later, the animals were challenged with a 5% TDI solution. Exertional breathing accompanied by the prolongation of expiratory phase was observed among the test animals. The number of the animals suffering from the attacks increased by the repetitive provocations. Although some of the guinea pigs suffered from anaphylaxis by the provocation procedures, the attacks including the anaphylactic shocks hardly brought about deaths in the animals. It was found that passive transfer of the symtom was possible in our experimental system. Both eosinophilic infiltration in the lung and eosinophilia in the peripheral bood were found among the test animals. This experimental model was developed by the appliaction of a simple chemical alone to the respiratory tract of guinea pigs. A significance of the model is discussed with the review of the literatures concerned

Comparison between alkali heat treatment and sprayed hydroxyapatite coating on thermally-sprayed rough Ti surface in rabbit model: Effects on bone-bonding ability and osteoconductivity.

In this study, we investigated the effect of different surface treatments (hydroxyapatite (HA) coating, alkali heat treatment, and no treatment) on the ability of bone to bond to a rough arc-sprayed Ti metal surface, using rabbit models. The bone-to-implant contacts for untreated, HA-coated, and alkali heat-treated implants were 21.2%, 72.1%, and 33.8% at 4 weeks, 21.8%, 70.9%, and 30.0% at 8 weeks, and 16.3%, 70.2%, and 29.9% at 16 weeks, respectively (n = 8). HA -coated implants showed significantly higher bone-to-implant contacts than the untreated and alkali heat-treated implants at all the time point, whereas alkali heat-treated implants showed significantly higher bone-to-implant contacts than untreated implants at 4 and 16 weeks. The failure loads in a mechanical test for untreated, HA coated, alkali heat-treated plates were 65.4 N, 70.7 N, and 90.8 N at 4 weeks, 76.1 N, 64.7 N, and 104.8 N at 8 weeks and 88.7 N, 92.6 N, and 118.5 N at 16 weeks, respectively (n = 8). The alkali heat-treated plates showed significantly higher failure loads than HA-coated plates at 8 and 16 weeks. The difference between HA-coated plates and untreated plates were not statistically significant at any time point. Thus HA coating, although it enables high bone-to-implant contact, may not enhance the bone-bonding properties of thermally-sprayed rough Ti metal surfaces. In contrast, alkali heat treatment can be successfully applied to thermally-sprayed Ti metal to enhance both bone-to-implant contact and bone-bonding strength

Effects of Microgravity on Cerebral Hemodynamics

After centuries of wonder, human being finally realized the decisive possibility of going to the moon a little more than 50 years ago, and in 1969 this became a reality, no longer a dream. The human body, however, is designed to live under 1 g as on Earth. Thus, it is important to understand what happens in the human body under microgravity in order to make rapid progress in space development. One of the most serious problems produced by microgravity is a fluid shift from lower to upper body. This cephalad fluid shift may change the hemodynamics in the brain. In this review, effects of actual or simulated microgravity on cerebral blood flow, intracranial pressure, formation of brain edema, and orthostatic intolerance will be discussed. These studies provide us lots of information not only to maintain the health of astronauts but also to treat senile persons who, on rare occasions, sit or stand up

A flexible sequential learning deficit in patients with Parkinson’s disease: a 2 × 8 button-press task

A 2 × 8 button-press task is a sequential hand movement task in which subjects are required to press eight pairs of buttons as accurately and quickly as possible. The 2 × 8 task allows us to examine flexible sequential learning, more aptly called sequence-unselective learning. Sequence-unselective learning is observed after repeated experiences with the task, when subjects have shown good progress in learning, with new sequences as well as previously learned ones. Although cognitive inflexibility has been reported in patients with Parkinson’s disease (PD), there have been few studies investigating their flexibility in sequential learning. We examined PD patients’ ability for sequence-unselective learning through the use of a 2 × 8 button-press task. In the first session, PD patients and subjects from the control group performed a sequential 2 × 8 task until the learning criterion was fulfilled (Session 1). After 1 month, they participated in other sessions: one involving the learned sequence (Session 2) and another involving the new sequence (Session 3). We found that PD patients made more errors than the normal control subjects only when learning the new sequence (Session 3) (P < 0.01). In Session 3, control subjects reached the learning target with fewer errors than in the Session 1 (normal sequence-unselective learning), whereas the PD patients did not exhibit such an improvement. Our results revealed a sequence-unselective deficit in PD patients. The deficit may help to emphasize the cognitive and physical inflexibility of PD

Variantes genéticas en el locus 9p21 contribuyen al desarrollo de arteriosclerosis a través de la modulación de ANRIL y CDKN2A/B

Registro creado en correspondencia al grado de doctora de Ada Congrains Castillo.Los estudios de asociación de todo el genoma (GWAS) han identificado variantes genéticas que contribuyen al riesgo de enfermedad cardiovascular (ECV) en el locus del cromosoma 9p21. La región asociada a CVD es adyacente a los dos inhibidores de quinasas dependientes de ciclina (CDKN) 2A y 2B y los últimos exones del ARN no codificante, ANRIL. Todavía no está claro cuál de estas transcripciones o cómo están involucradas en la patogénesis de la aterosclerosis.Genome-wide association studies (GWAS) have identified genetic variants contributing to the risk of cardiovascular disease (CVD) at the chromosome 9p21 locus. The CVD-associated region is adjacent to the two cyclin dependent kinase inhibitors (CDKN)2A and 2B and the last exons of the non-coding RNA, ANRIL. It is still not clear which of or how these transcripts are involved in the pathogenesis of atherosclerosis.Japón. Programa de Promoción de Estudios Fundamentales en el Instituto Nacional de Innovación Biomédica de Japón (HR: 22-2-5), el Ministerio de Educación, Cultura, Deportes, Ciencia y Tecnología de Japón (KK: 22510211) y la Fundación NOVARTIS para la Investigación Gerontológica (KK).Tesi