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T Kaga

Publications and source records attributed to T Kaga.

At least 19 recordsLinked to original sources
PubMed2003

Antagonism of ghrelin receptor reduces food intake and body weight gain in mice.

BACKGROUND AND AIMS: Ghrelin, an endogenous ligand for growth hormone secretagogue receptor (GHS-R), is an appetite stimulatory signal from the stomach with structural resemblance to motilin. We examined the effects of the gastric peptide ghrelin and GHS-R antagonists on energy balance and glycaemic control in mice. MATERIALS AND METHODS: Body weight, fat mass, glucose, insulin, and gene expression of leptin, adiponectin, and resistin in white adipose tissue (WAT) were measured after repeated administrations of ghrelin under a high fat diet. Gastric ghrelin gene expression was assessed by northern blot analysis. Energy intake and gastric emptying were measured after administration of GHS-R antagonists. Repeated administration of GHS-R antagonist was continued for six days in ob/ob obese mice. RESULTS: Ghrelin induced remarkable adiposity and worsened glycaemic control under a high fat diet. Pair feeding inhibited this effect. Ghrelin elevated leptin mRNA expression and reduced resistin mRNA expression. Gastric ghrelin mRNA expression during fasting was increased by a high fat diet. GHS-R antagonists decreased energy intake in lean mice, in mice with diet induced obesity, and in ob/ob obese mice; it also reduced the rate of gastric emptying. Repeated administration of GHS-R antagonist decreased body weight gain and improved glycaemic control in ob/ob obese mice. CONCLUSIONS: Ghrelin appears to be closely related to excess weight gain, adiposity, and insulin resistance, particularly under a high fat diet and in the dynamic stage. Gastric peptide ghrelin and GHS-R may be promising therapeutic targets not only for anorexia-cachexia but also for obesity and type 2 diabetes, which are becoming increasingly prevalent worldwide.

Adiponectin↗
PubMed2001

Optical coherence tomography of bleb-like subretinal lesions after retinal reattachment surgery.

PURPOSE: To report the optical coherence tomographic characteristics of persistent bleb-like subretinal lesions after retinal reattachment surgery, including scleral buckling and cryopexy. METHODS: Case reports. RESULTS: In two eyes of two patients yellow to yellowish-orange bleb-like lesions were found in the posterior pole after retinal reattachment surgery. The common aspects of the surgery were scleral buckling procedures and cryopexy. There were subretinal precipitates in some of the lesions. The lesions showed no associated leakage during fluorescein or indocyanine green angiography. Optical coherence tomography demonstrated that the bleb-like lesions were tiny retinal detachments. CONCLUSION: Optical coherence tomography examination of bleb-like subretinal lesions showed that they were actually retinal detachments. Our patients and previously reported patients developed these lesions after scleral buckling and cryopexy. These lesions may represent persistent retinal detachment because of the presence of protein in the subretinal fluid.

Adult↗
PubMed2001

Combined hamartoma of the retina and retinal pigment epithelium associated with juvenile nasopharyngeal angiofibroma.

PURPOSE: To report a patient who had concomitant combined hamartoma of the retinal pigment epithelium and retina and juvenile nasopharyngeal angiofibroma. METHOD: Case report. RESULTS: An 18-year-old man presented with a juvenile nasopharyngeal angiofibroma and a combined hamartoma of the retina and retinal pigment epithelium in the ipsilateral eye. The diagnosis of juvenile nasopharyngeal angiofibroma was confirmed by histopathology, and the diagnosis of combined hamartoma was established by typical ophthalmoscopic and fluorescein angiographic findings. CONCLUSION: Juvenile nasopharyngeal angiofibroma may be associated with combined hamartoma of the retina and retinal pigment epithelium.

Adolescent↗
PubMed2001

Emerging functions of neuropeptide Y Y(2) receptors in the brain.

The Y(2) receptor is the predominant neuropeptide Y (NPY) receptor subtype in the brain. Y(2) receptor mRNA is discretely distributed in the brain, including specific subregions of the hippocampus and the hypothalamus, and is largely consistent with the distribution of Y(2) receptor protein demonstrated by radioligand-binding methods. Y(2) receptor-mediated effects have been reported principally based on the observations using the C-terminal fragments of NPY. Recent studies indicate an involvement of the receptor in food intake, gastrointestinal motility, cardiovascular regulation, and neuronal excitability. Very recently, Y(2) receptor selective antagonist has been developed and Y(2) receptor-deficient animals have been created. These new pharmacological tools will help to clarify the roles of this receptor in brain functions.

Animals↗
PubMed2001

Ghrelin is an appetite-stimulatory signal from stomach with structural resemblance to motilin.

BACKGROUND & AIMS: : Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, was recently identified in the rat stomach. We examined the effects of the gastric peptide ghrelin on energy balance in association with leptin and vagal nerve activity. METHODS: : Food intake, oxygen consumption, gastric emptying, and hypothalamic neuropeptide Y (NPY) messenger RNA expression were measured after intra-third cerebroventricular or intraperitoneal injections of ghrelin in mice. The gastric vagal nerve activity was recorded after intravenous administration in rats. Gastric ghrelin gene expression was assessed by Northern blot analysis. Repeated coadministration of ghrelin and interleukin (IL)-1 beta was continued for 5 days. RESULTS: : Ghrelin exhibited gastroprokinetic activity with structural resemblance to motilin and potent orexigenic activity through action on the hypothalamic neuropeptide Y (NPY) and Y(1) receptor, which was lost after vagotomy. Ghrelin decreased gastric vagal afferent discharge in contrast to other anorexigenic peptides that increased the activity. Ghrelin gene expression in the stomach was increased by fasting and in ob/ob mice, and was decreased by administration of leptin and IL-1 beta. Peripherally administered ghrelin blocked IL-1 beta-induced anorexia and produced positive energy balance by promoting food intake and decreasing energy expenditure. CONCLUSIONS: : Ghrelin, which is negatively regulated by leptin and IL-1 beta, is secreted by the stomach and increases arcuate NPY expression, which in turn acts through Y(1) receptors to increase food intake and decrease energy expenditure. Gastric peptide ghrelin may thus function as part of the orexigenic pathway downstream from leptin and is a potential therapeutic target not only for obesity but also for anorexia and cachexia.

Amino Acid Sequence↗
PubMed2001

Cocaine-amphetamine-regulated transcript influences energy metabolism, anxiety and gastric emptying in mice.

This study was designed to investigate the effects of cocaine-amphetamine-regulated transcript (CART), a recently discovered hypothalamic neuropeptide, on food intake, anxiety, oxygen consumption and gastric emptying in mice. Intracerebroventricular (i. c. v.) injection of CART (1 - 100 pmol) markedly reduced food intake in a dose-related manner. A significant decrease was observed 20 min after i. c. v. injection of CART and continued for four hours. In the elevated plus maze test, i. c. v. CART injection significantly raised the normal preference for the closed arms. Furthermore, the i. c. v. injection of CART significantly reduced oxygen consumption and gastric emptying rate. These results suggest that CART modulates feeding, emotion, and autonomic functions in mice.

Animals↗
PubMed2001

A role of ghrelin in neuroendocrine and behavioral responses to stress in mice.

Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor, was recently identified in the rat stomach. Previous studies have shown that ghrelin potently increases growth hormone release and food intake. We examined the effects of the gastric peptide ghrelin on anxiety-like behavior in association with the hypothalamic-pituitary-adrenal axis in mice. Both intra-third cerebroventricular and intraperitoneal administration of ghrelin potently and significantly induced anxiogenic activities in the elevated plus maze test. Ghrelin gene expression in the stomach was increased by tail pinch stress as well as by starvation stress. Administration of a corticotropin-releasing hormone (CRH) receptor antagonist significantly inhibited ghrelin-induced anxiogenic effects. Peripherally administered ghrelin significantly increased CRH mRNA, but not urocortin mRNA expression in the hypothalamus. Furthermore, intraperitoneal injection of ghrelin produced a significant dose- dependent increase in serum corticosterone levels. These findings suggest that ghrelin may have a role in mediating neuroendocrine and behavioral responses to stressors and that the stomach could play an important role, not only in the regulation of appetite, but also in the regulation of anxiety.

Animals↗
PubMed2001

Modest overexpression of neuropeptide Y in the brain leads to obesity after high-sucrose feeding.

Neuropeptide Y (NPY), one of the most abundant peptide transmitters in the mammalian brain, is assumed to play an important role in feeding and body weight regulation. However, there is little genetic evidence that overexpression or knockout of the NPY gene leads to altered body weight regulation. Previously, we developed NPY-overexpressing mice by using the Thy-1 promoter, which restricts NPY expression strictly within neurons in the central nervous system, but we failed to observe the obese phenotype in the heterozygote. Here we report that in the homozygous mice, overexpression of NPY leads to an obese phenotype, but only after appropriate dietary exposure. NPY-overexpressing mice exhibited significantly increased body weight gain with transiently increased food intake after 50% sucrose--loaded diet, and later they developed hyperglycemia and hyperinsulinemia without altered glucose excursion during 1 year of our observation period.

Aging↗
PubMed2001

[Abnormality in feeding and body weight regulation in obesity].

Obesity is, with rare exceptions, a complex phenotype resulting from interactions between environmental and genetic risk factor. Obesity is associated with diabetes, hypertension, and hyperlipidemia, leading to arteriosclerosis. Dysregulation of food intake and energy expenditure, and thus energy homeostasis, is now recognized as playing a major role in development of obesity. A detailed understanding of the physiology and genetics of the regulatory systems is critical for the development of new approaches for treating obesity and its sequelae.

Adult↗
PubMed2001

[A role of visiting nurses in providing the terminal patients with their desirable life-discussion regarding the place of death of the patients who were registered for visiting nurse system].

AIM: To evaluate the prognosis of the patients who had visiting nurse service and discuss the place of death (life at the terminal stage). To determine the roles of visiting nurses in providing the patients at a terminal stage with their desirable life till death. METHODS: A total of 180 patients, who were registered for their home healthcare service in our Shonan Kamakura General Hospital and died between January 2000 and February 2001, were subjected to the study. All the subjects were classified into 3 groups according to the places of their death, 1) death at home, 2) death in the hospital and 3) death upon arrival after the admission to the hospital. Moreover, the following items were also surveyed and analyzed: 1) diagnosis (name of diseases), 2) cause of death, 3) age, 4) family structure, 5) whether their primary care physicians explained the prognosis and possible expected conditions to the patients and their family before hand, and 6) how the visiting nurses interact with the patients and their family members. RESULTS: Sixty-six patients died at home, 105 in the hospital and 9 upon arrival at the hospital. During this survey period, there were a total of 5,274 and 5,574 visits by primary care physicians and visiting nurses, respectively. The patients who died at home were more often observed in the patients whose primary care physicians explained their conditions to them and whose visiting nurses closely related to them. Moreover, the patients with malignant tumor also more often died at home. On the contrary, there were very few patients with chronic diseases, with whom death at home was accepted and agreed before hand, and there were some cases with chronic diseases who died inside of the ambulance transported on the way to the hospital after a sudden change in their conditions. DISCUSSION AND CONCLUSION: In order to have the patients live their desirable life till their death, it is required for the caretakers to prepare their mind for the day of the patient's death in addition to the patient's own wishes. For the patients with malignant tumor, it is easy to predict their prognosis, thus the caretakers can get prepared for the day of the patient's death. On the contrary, in case of the patients with chronic diseases, it is more difficult for the caretakers to experience an indefinite time with the patients since their prognosis is generally longer but the sudden change in their conditions may give the caretakers a high anxiety. Thus, it is essential for the visiting nurses to play a role as a mediator to interact between the patients and their family members, and their primary care physicians, and to establish a trustful relationship with the patients while their conditions are still stable. Moreover, similar to the malignant patients, the visiting nurses should explain the situations to the patients with chronic diseases, that they can choose the place of their own death and specific medical treatment at emergency and can decide the detail for their terminal stage with their family members. Thus, it was considered to be very important that the visiting nurses should frequently confirm these issues with the patients and their family according to their conditions.

Aged↗
PubMed1999

Decreased food intake and body weight in pancreatic polypeptide-overexpressing mice.

BACKGROUND & AIMS: Pancreatic polypeptide (PP) is a 36-amino acid hormone produced by F cells within the pancreatic islets and the exocrine pancreas. The definitive function of PP in mammalian physiology remains to be determined. This study examined the effects of chronic overexpression of PP through the development of PP transgenic mice. METHODS: PP transgenic mice were created by using mouse PP complementary DNA under the control of the cytomegalovirus immediate early enhancer-chicken beta-actin hybrid promoter (pCAGGS expression vector). RESULTS: A unique line of transgenic mice was created that overexpresses PP in the pancreatic islets with low levels of expression in other tissues including the brain. Plasma PP concentrations were more than 20 times higher than those of control littermates. However, PP overproduction led to postnatal lethality in half of the pups because of markedly decreased milk intake. The remaining PP transgenic mice gained less weight with specifically reduced food intake and fat mass compared with controls, a result that was more evident in male than in female mice. The transgenic mice exhibited a reduced rate of gastric emptying of a solid meal but had normal oxygen consumption and fasting leptin levels. Immunoneutralization with anti-PP antiserum reversed the phenotypic changes of transgenic animals. CONCLUSIONS: PP could be involved in feeding and body weight regulation partly through regulation of gastric emptying.

Animals↗
PubMed1999

Cloning and sequencing of beta-mannosidase gene from Aspergillus aculeatus no. F-50.

The manB gene, coding for a unique beta-mannosidase (MANB) of Aspergillus aculeatus, was cloned from genomic and cDNA libraries, and sequenced. The gene consists of 2,811 bp encoding a polypeptide of 937 amino acid residues with a molecular mass of 104,214 Da. The A. aculeatus MANB shared amino acid sequence identity with MANB of human (24%), goat (24%), bovine (24%), and Caenorhabditis elegans (22%). When the A. aculeatus MANB was compared with other related enzymes, a Glu residue corresponding to the active site identified by the Escherichia coli beta-galactosidase and the human beta-guclonidase was conserved. This is the first fungal gene that encodes MANB.

Amino Acid Sequence↗
PubMed1995

[The outline of in-home medical care in Japan].

In-home medical care is an issue which has come to the forefront recently, but it is as yet an undeveloped and unorganized field in Japan. However, in-home medical care is an extremely vital aspect in community medical care and the needs of the population in this field are expected to gradually expand. The human resources which will be responsible for carrying out in-home medical care is the focus of this study. Recently, the young physicians who have begun their practice as family physicians are capable of using IVH and other medical techniques. They are self-assertive in visiting their patients at home and a revolution in medical care awareness has begun to evolve. Old people's home visit nursing stations are certain to increase and the range of nursing duties which can be carried out in the home will become an issue. In addition, the role of home helpers is essential, although they are not medical personnel. The focus of in-home medical care services which will be placed under the supervision of a physician, will be the patient; and it is important that nurses, certified care workers, home helpers, etc. cooperate mutually in the care of the patient. Implementing in-home medical care as efficiently as possible will enable medical care to meet the needs of the population. In the 21 st century "in-home medical care" is anticipated to function and inseparably with hospital medical care and fully it is expected to become a fixed institution among the Japanese people.

Community Health Services↗
PubMed1992

Giant air cell of the petrous apex: a possible cause of facial hypalgesia.

A giant air cell of the left petrous apex was found in a 23-year-old man with ipsilateral facial hypalgesia. The size of the giant air cell depicted on computed tomography was 1.5 x 2.0 x 2.0 cm. A coronal T1-weighted magnetic resonance image showed that the trigeminal nerve was compressed superomedially by a large signal void area that was probably a result of excessive pneumatization of the petrous apex. It is suggested that the facial hypalgesia was caused by the compression by the giant air cell of the petrous apex on the trigeminal nerve.

Adult↗