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Amino Acids That Centrally Influence Blood Pressure and Regional Blood Flow in Conscious Rats
Yumi Takemoto
Journal of Amino Acids , 2012, DOI: 10.1155/2012/831759
Abstract: Functional roles of amino acids have increasingly become the focus of research. This paper summarizes amino acids that influence cardiovascular system via the brain of conscious rats. This paper firstly describes why amino acids are selected and outlines how the brain regulates blood pressure and regional blood flow. This section includes a concise history of amino acid neurotransmitters in cardiovascular research and summarizes brain areas where chemical stimulations produce blood pressure changes mainly in anesthetized animals. This is followed by comments about findings regarding several newly examined amino acids with intracisternal stimulation in conscious rats that produce changes in blood pressure. The same pressor or depressor response to central amino acid stimulations can be produced by distinct mechanisms at central and peripheral levels, which will be briefly explained. Thereafter, cardiovascular actions of some of amino acids at the mechanism level will be discussed based upon findings of pharmacological and regional blood flow measurements. Several examined amino acids in addition to the established neurotransmitter amino acids appear to differentially activate brain structures to produce changes in blood pressure and regional blood flows. They may have physiological roles in the healthy brain, but pathological roles in the brain with cerebral vascular diseases such as stroke where the blood-brain barrier is broken. 1. Introduction When the rat spontaneously performs an action such as grooming [1] or walking [2], changes in regional blood flows for head and legs are produced. The brain appropriately regulates blood supply to organs needed for planning of each behavior. For matching cardiovascular demand to each behavior, various kinds of potential neurotransmitters and neuromodulators should work in neuronal networks of the brain relating to the cardiovascular system and behavioral planning. A list of neurotransmitters includes the amino acids glutamate and GABA (gamma-amino-butyric acid) which are well established as endogenously produced excitatory and inhibitory agonists, respectively [3], and appear to play a pivotal role in the central nervous system relating to cardiovascular regulation [4–7]. However, it has been expanding to range the kind and the number of mediators between brain cells from classic neurotransmitter biogenic amines to gaseous neurotransmitters [8] and to gliotransmitters [9]. With respect to amino acids, the concentration of most amino acids in the cerebrospinal fluid is lower than those in the blood [10]. The
Intracisternally Injected L-Proline Activates Hypothalamic Supraoptic, but Not Paraventricular, Vasopressin-Expressing Neurons in Conscious Rats
Yumi Takemoto
Journal of Amino Acids , 2011, DOI: 10.4061/2011/230613
Abstract: When injected into specific rat brain regions, the neurotransmitter candidate L-proline produces various cardiovascular changes through ionotropic excitatory amino acid receptors. The present study used an immunohistochemical double-labeling approach to determine whether intracisternally injected L-proline in freely moving rats, which increases blood pressure, activates hypothalamic vasopressin-expressing neurons and ventral medullary tyrosine-hydroxylase- (TH-) containing neurons. Following injection of L-proline, the number of activated hypothalamic neurons that coexpressed vasopressin and c-Fos was much greater in the supraoptic nucleus (SON) than in the paraventricular nucleus (PVN) of rats with increased blood pressure. The number of activated TH-containing neurons was significantly greater following L-proline treatment than following control injections of artificial cerebrospinal fluid (ACSF). These results clearly demonstrate that intracisternally injected L-proline activates hypothalamic supraoptic, but not paraventricular, vasopressin-expressing neurons and medullary TH-containing (A1/C1) neurons in freely moving rats. 1. Introduction The nonessential imino acid L-proline has been proposed to be a neurotransmitter or neuromodulator of the central nervous system [1–3]. It produces various functional changes in animals, such as cardiovascular changes in rats [4–8] and sedation as well as hypnotic effects under stressful conditions in chicks [9, 10]. Intracisternal injections of L-proline, but not D-proline, have been shown to cause an increase in blood pressure in freely moving rats in a dose-dependent manner via ionotropic excitatory amino acid receptors in the brain [4, 5, 11]. This hypertensive response to centrally administered L-proline can be almost inhibited by intravenous preinjection of a vasopressin V1 receptor antagonist alone and augmented in ganglionic blocking rats where the augmented response was completely abolished by the additional vasopressin receptor antagonist [11], suggesting that the L-proline-induced pressor response could be mainly mediated by the release of hypothalamic vasopressin into the blood stream. Previous studies have shown that intracisternally injected dye robustly stains the medullary surface [12, 13]. These results suggest that intracisternally injected L-proline might diffuse and reach the medullary A1 catecholamine neurons, which send their terminals to vasopressin-expressing neurons in both the paraventricular nucleus (PVN) and the supraoptic nucleus (SON) of the hypothalamus [14]. The goal of this study
The most common otorhinolaryngologic manifestations of granulomatous diseases
Fornazieri, Marco Aurélio,Yamaguti, Hellen Yumi,Moreira, Jemima Herrero,Takemoto, Lúcio Eidy
International Archives of Otorhinolaryngology , 2008,
Abstract: Introduction: Granulomatous diseases result from immunopathologic processes in which there is a failure in the fagocitosis of intracellular organisms. They can cause oral, nasal and pharyngeal mucosa ulcers, vocal cords lesions, otorrhoea and oropharyngeal vegetant lesions. Objective: Describing the most frequent otorhinolaryngologic manifestations in common granulomatous diseases: hanseniasis, paracoccidioidomycosis, leishmaniasis. Method: A retrospective study has been carried out from records of patients diagnosed with the abovementioned diseases between January 1, 2005 and October 31, 2007 in an infectology ambulatory of a tertiary hospital. Results: 142 patients were evaluated; 93 with leishmaniasis, 39 with paracoccidioidomycosis and 10 with hanseniasis. In 93 cases of leishmaniasis, 16 (17.2%) had mucosal affection, and the most common signs were septum perforation and nasal mucosal ulcers, both with 8 cases. In paracoccidioidomycosis, oropharyngeal ulcer was the most frequent, with 15 cases (38,4%). Conclusion: Head and neck signs and symptoms are common in patients with leishmaniasis and paracoccidioidomycosis. Nasal manifestations prevail in leishmaniasis and oropharyngeal ones in paracoccidioidomycosis.
Manifesta es otorrinolaringológicas mais comuns das doen as granulomatosas
Fornazieri, Marco Aurélio,Yamaguti, Hellen Yumi,Moreira, Jemima Herrero,Takemoto, Lúcio Eidy
Arquivos Internacionais de Otorrinolaringologia , 2008,
Abstract: Introdu o: As doen as granulomatosas s o decorrentes de processos imunopatológicos em que há falha na fagocitose de organismos intracelulares. Podem ocasionar úlceras nas mucosas orais, nasais e faríngeas, les es nas pregas vocais, otorréia e les es vegetantes orofaríngeas. Objetivo: Descrever as manifesta es otorrinolaringológicas mais freqüentes em doen as granulomatosas comuns: hanseníase, paracoccidioidomicose e leishmaniose. Método: Realizou-se estudo retrospectivo dos prontuários de pacientes diagnosticados com as doen as citadas acima, do período de 1o de janeiro de 2005 a 31 de outubro de 2007, no ambulatório de infectologia de um hospital terciário. Resultados: Avaliaram-se 142 pacientes; 93 com diagnóstico de leishmaniose, 39 de paracoccidiodomicose e 10 de hanseníase. Dos 93 casos de leishmaniose, 16 (17,2%) apresentavam comprometimento mucoso, sendo os sinais mais freqüentes a perfura o septal e úlcera em mucosa nasal, ambos com 8 casos. Na paracoccidiodomicose, a les o mucosa mais freqüente foi a ulcera o orofaríngea com 15 casos (38,4%). Conclus o: Sinais e sintomas de cabe a e pesco o s o comuns nos pacientes com leishmaniose e paracoccidioidomicose. As manifesta es nasais prevalecem na leishmaniose e as orofaríngeas na paracoccidioidomicose.
Coastal Planning Strategies for Adaptation to Sea Level Rise: A Case Study of Mokpo, Korea  [PDF]
Yumi Lee
Journal of Building Construction and Planning Research (JBCPR) , 2014, DOI: 10.4236/jbcpr.2014.21007
Abstract: Climate change and sea level rise necessitate adaptation strategies for coastal areas. This paper showcases five strategies for sea level rise adaptation: hard protection, soft protection, accommodation, retreat, and attack. This study proposes adaptation measures and a phased development strategy for coastal areas of Mokpo, an old port city on the southwestern tip of the Korean Peninsula that has been expanded by land reclamation. Mokpo presently experiences frequent flooding during high-water and storm events; due to their low elevation and land subsidence, most of the reclaimed areas are susceptible to future inundation via sea level rise. The fundamental adaptation strategies for the impact areas are: hard protection of important infrastructures via multi-tiered terraces; the retreat of coastal developments accompanied by green buffer zones such as wetlands and parks to accommodate temporary inundation; and up-leveling the ground for new development and phased relocation of existing development. Through the case study of Mokpo, the paper emphasizes the importance of resilient planning strategies for urban development, and highlights both the challenges and opportunities for sea level rise adaptation.
Protecting the Coastline from the Effects of Climate Change: Adaptive Design for the Coastal Areas of Gangneung, Korea  [PDF]
Yumi Lee
Journal of Building Construction and Planning Research (JBCPR) , 2015, DOI: 10.4236/jbcpr.2015.32011
Abstract: The purpose of this research is to present design strategies to enable coastal areas to adapt to climate change and maintain the coastlines by addressing the environmental and urban issues. Gangneung is a tourist attraction situated on South Korea’s east coast, and there is an urgent need for integrated research on strategies to prevent the loss of sandy beaches and the damage caused by storm surges and high swell. This research has two objectives: The first is to offer an overview and describe the characteristics of exemplary projects carried out to manage the storm damage while maintaining the coastlines. The second is to propose a design model that can be applied to coastal areas susceptible to climate change by analyzing the design strategies and the current conditions of the Gangneung coastal area. In the case of Gangneung, the damage caused by the storm surges and high swells are more severe compared to inundation caused by sea level rise because of the steep slope and deep water. Therefore, adaptive design strategies are mainly focused on accommodation and retreat strategies that consider these characteristics by moving the coastal roads behind the pine forest and raising the coastal buildings to connect the coast to the forest and to prevent coastal erosion. This research has the potential to be used as an exemplary design adaptation for coastal erosion as well as a basis for regulating the land use policy in areas susceptible to flood by establishing guidelines for publicly funded developments, and preparing long-term relocation plans for the existing coastal developments to create a sustainable and resilient future for the coastal areas.
Relationship between Depression and Aging Awareness among Frail Older Adults Living Alone in Japan  [PDF]
Yumi Okinaka
Health (Health) , 2018, DOI: 10.4236/health.2018.1011117
Abstract: Aim: This study aimed to clarify the relationship between depression and aging awareness among older adults living alone with low-level long-term-care needs. Methods: Participants were older adults aged 65 years and older in Japan. Data were collected via an anonymous questionnaire. Participants were categorized based on their long-term care need level, from Support 1 to Care 2 according to the care insurance criteria in Japan. The questionnaire included: 1) the Geriatric Depression Scale-Short Version-Japanese (GDS); 2) items on aging life satisfaction at present, and positive and negative aging awareness in the past (when they were young); 3) the SF-8 to assess health-related quality of life; 4) the Lubben Social Network Scale-6 (LSNS-6); and 5) items on the use of care services. Data were analyzed using multiple logistic regression analysis. Results: In total, 457 participants were recruited. Their mean age was 83.9 ± 6.5 years; 39.8% of the participants had a GDS score of 6 and above. In the regression analysis, the GDS score significantly correlated with aging life satisfaction at present, negative aging awareness in the past, mental health, and social networks. Conclusion: Older adults living alone who have positive views of their current lives and lacked negative views of aging in their younger years were resistant to depression after being certified as requiring low-level long-term care. Preventing and improving depression in this population requires community-based support to expand their social networks and to help individuals of all ages view the aging process positively.
Heat Shock Factor 1 Contributes to Ischemia-Induced Angiogenesis by Regulating the Mobilization and Recruitment of Bone Marrow Stem/Progenitor Cells
Masayuki Kubo, Tao-Sheng Li, Hiroshi Kurazumi, Yoshihiro Takemoto, Mako Ohshima, Yumi Yamamoto, Arata Nishimoto, Akihito Mikamo, Mitsuaki Fujimoto, Akira Nakai, Kimikazu Hamano
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037934
Abstract: Bone marrow (BM)-derived stem/progenitor cells play an important role in ischemia-induced angiogenesis in cardiovascular diseases. Heat shock factor 1 (HSF1) is known to be induced in response to hypoxia and ischemia. We examined whether HSF1 contributes to ischemia-induced angiogenesis through the mobilization and recruitment of BM-derived stem/progenitor cells using HSF1-knockout (KO) mice. After the induction of ischemia, blood flow and microvessel density in the ischemic hindlimb were significantly lower in the HSF1-KO mice than in the wild-type (WT) mice. The mobilization of BM-derived Sca-1- and c-kit-positive cells in peripheral blood after ischemia was significantly lower in the HSF1-KO mice than in the WT mice. BM stem/progenitor cells from HSF1-KO mice showed a significant decrease in their recruitment to ischemic tissue and in migration, adhesion, and survival when compared with WT mice. Blood flow recovery in the ischemic hindlimb significantly decreased in WT mice receiving BM reconstitution with donor cells from HSF1-KO mice. Conversely, blood flow recovery in the ischemic hindlimb significantly increased in HSF1-KO mice receiving BM reconstitution with donor cells from WT mice. These findings suggest that HSF1 contributes to ischemia-induced angiogenesis by regulating the mobilization and recruitment of BM-derived stem/progenitor cells.
The Effects of Mechanical Stress on the Growth, Differentiation, and Paracrine Factor Production of Cardiac Stem Cells
Hiroshi Kurazumi, Masayuki Kubo, Mako Ohshima, Yumi Yamamoto, Yoshihiro Takemoto, Ryo Suzuki, Shigeru Ikenaga, Akihito Mikamo, Koichi Udo, Kimikazu Hamano, Tao-Sheng Li
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0028890
Abstract: Stem cell therapies have been clinically employed to repair the injured heart, and cardiac stem cells are thought to be one of the most potent stem cell candidates. The beating heart is characterized by dynamic mechanical stresses, which may have a significant impact on stem cell therapy. The purpose of this study is to investigate how mechanical stress affects the growth and differentiation of cardiac stem cells and their release of paracrine factors. In this study, human cardiac stem cells were seeded in a silicon chamber and mechanical stress was then induced by cyclic stretch stimulation (60 cycles/min with 120% elongation). Cells grown in non-stretched silicon chambers were used as controls. Our result revealed that mechanical stretching significantly reduced the total number of surviving cells, decreased Ki-67-positive cells, and increased TUNEL-positive cells in the stretched group 24 hrs after stretching, as compared to the control group. Interestingly, mechanical stretching significantly increased the release of the inflammatory cytokines IL-6 and IL-1β as well as the angiogenic growth factors VEGF and bFGF from the cells in 12 hrs. Furthermore, mechanical stretching significantly reduced the percentage of c-kit-positive stem cells, but increased the expressions of cardiac troponin-I and smooth muscle actin in cells 3 days after stretching. Using a traditional stretching model, we demonstrated that mechanical stress suppressed the growth and proliferation of cardiac stem cells, enhanced their release of inflammatory cytokines and angiogenic factors, and improved their myogenic differentiation. The development of this in vitro approach may help elucidate the complex mechanisms of stem cell therapy for heart failure.
The Influence of Surrounding Ground Floor Facilities on the Use of Privately Owned Public Spaces in Seoul  [PDF]
Bonwoo Koo, Yumi Lee
Journal of Building Construction and Planning Research (JBCPR) , 2015, DOI: 10.4236/jbcpr.2015.32010
Abstract: Seoul’s privately owned public space (POPS) initiative has achieved quantitative success since its introduction in the early 1990s. However, POPSs have been frequently criticized for failing to correspond with the urban context in which they are created and are thus often underused. Association between surrounding urban context and the use of POPS is acknowledged, but specific elements of the urban context associated with the use of POPS and the extent of association are unclear. In this study, the relationship between constituent elements of 48 POPSs including the surrounding ground floor facility use and the use of those spaces in Seoul’s central business district was measured by multiple regression analysis. The results present empirical evidence of a substantial relationship between assembly, mercantile, and business facilities on ground floors of surrounding buildings and the use of POPS. As the surrounding ground floor facility use showed an overriding relationship with the use of POPS that possibly overshadowed the influence of secondary determinants, the 48 POPSs were divided into two groups: those surrounded by commercial facilities and those surrounded by business facilities. The use of POPSs surrounded by commercial facilities was associated with additional variables including the proximity to transit stations and crosswalks. Models using the sample of POPSs surrounded by business facilities were not statistically significant. Based on these results, this paper emphasizes the importance of creating POPSs in connection with desirable surrounding facilities. This study also suggests that anticipation of the usage patterns of POPSs and establishment of guidelines supporting those patterns may be viable by investigating preexisting urban contexts.
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