Orexins and orexin receptors: a family of hypothalamic neuropeptides and G protein-coupled receptors that regulate feeding behavior.
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Carrier Proteins↗
Biomedical subjects
T Sakurai
Publications and source records attributed to T Sakurai.
Orexins and orexin receptors: a family of hypothalamic neuropeptides and G protein-coupled receptors that regulate feeding behavior.
The hypothalamus plays a central role in the integrated control of feeding and energy homeostasis. We have identified two novel neuropeptides, both derived from the same precursor by proteolytic processing, that bind and activate two closely related (previously) orphan G protein-coupled receptors. These peptides, termed orexin-A and -B, have no significant structural similarities to known families of regulatory peptides. prepro-orexin mRNA and immunoreactive orexin-A are localized in neurons within and around the lateral and posterior hypothalamus in the adult rat brain. When administered centrally to rats, these peptides stimulate food consumption. prepro-orexin mRNA level is up-regulated upon fasting, suggesting a physiological role for the peptides as mediators in the central feedback mechanism that regulates feeding behavior.
Animals↗
Genomic DNA cloning of the region encoding nitric oxide reductase in Paracoccus halodenitrificans and a structure model relevant to cytochrome oxidase.
The structural genes for the NO reductase in Paracoccus halodenitrificans, norC, norB, and norQ were sequenced. The norC and norB encode the cytochrome c (NorC) and cytochrome b (NorB) subunits, respectively. The matured NorC (17,258 Da, 148 residues) has a binding motif (CXYCH) for heme c, which is axially coordinated by His65 and Met115. NorB (52,337 Da, 451 residues) has twelve putative transmembrane helices and the 19% sequence homology with the subunit I of cytochrome oxidase from Paracoccus denitrificans. Several histidine and glutamate residues were identified as the ligands for two hemes b and a non-heme iron in comparison with the sequence of cytochrome oxidase. The higher-order model structures constructed from the amino acid sequences of NorC and NorB showed the topology of the helical segments and the locations of the metal centers.
Bacterial Proteins↗
Observation of Cu-N3- stretching and N3- asymmetric stretching bands for mono-azide adduct of Rhus vernicifera laccase.
Mono-azide adduct of Rhus vernicifera laccase, a multicopper oxidase containing one type-1 (blue) copper, one type-2 (non-blue normal) copper, and a pair of type-3 (binuclear and EPR silent) coppers, of which type-2 and type-3 coppers constitute a trinuclear site, was investigated with resonance Raman (RR) and Fourier transform infrared (FT-IR) spectroscopies as a step toward elucidation of the structure and function of the trinuclear site. The Cu-N3- stretching (vCu-N3-) RR band was observed for azide-bound multicopper oxidases for the first time. The vCu-N3- band was located at 400 cm-1 for mono-14N3- laccase, which shifted to 396 cm-1 with the 15N14N14N3- analog. The N3- asymmetric stretching (v(N3-)asym) band was observed by FT-IR spectroscopy at 2035 cm-1 for mono-14N3- laccase and at 2025 cm-1 for the 15N14N14N3- analog. The vCu-N3- and v(N3-)asym frequencies and their 15N14N14N- isotope shifts for azido laccase correspond well with those of metazido hemocyanin, indicating that both derivatives should have a similar binding geometry of azide.
Azides↗
Long pedunculated colonic polyp composed of mucosa and submucosa: proposal of a new entity, colonic muco-submucosal elongated polyp.
We encountered 15 patients with colonic polyps showing histologic features that did not belong to any of the known categories. All polyps were elongated and drumstick-shaped, with lengths of 12 to 160 (mean, 29 mm) mm. Histologically, the polyps were covered with normal mucosa and consisted of edematous, loose, fibrous, connective tissues and dense, fibrous submucosal layers, often showing dilation of blood vessels and lymphatics. Although the mechanism of generation of such polyps remains unknown, their elongation may be caused by intestinal motion. Because this kind of polyp has not been described previously outside Japan, we here introduce a new type of polyp, which we have proposed calling the colonic muco-submucosal elongated polyp.
Adult↗
Video-enhanced microscopic visualization of apoptotic cell death caused by anti-Fas antibody in living human glioma cells.
To study the morphological changes of anti-Fas antibody-mediated apoptosis in living U251-SP human glioma cells, we employed video-enhanced contrast differential interference contrast (VEC-DIC) microscopy. In our previous study, we investigated the susceptibility of human glioma cell lines to anti-Fas Immunoglobulin M (IgM) antibody. U251-SP cells express Fas antigen on their surface. The cells exposed to anti-Fas antibody underwent apoptotic cell death, as reported previously. In this study, morphological changes of apoptosis characterized by bleb formation, shrinkage of cells, and nuclear condensation were observed under VEC-DIC microscopy in U251-SP human glioma cells treated with anti-Fas antibody. These results demonstrate the usefulness of VEC-DIC microscopy to study the process of apoptotic cell death.
Antibodies↗
Transumbilical resection and umbilical plasty for patent omphalomesenteric duct.
This paper describes a transumbilical resection and umbilical plasty for treatment of a patent omphalomesenteric duct (POMD). In a newborn infant with a POMD, a skin incision was made circumscribing the mucocutaneous junction of the protruded duct. The duct was completely extirpated with a wedge resection of the connection to the intestine and an umbilical plasty was performed. The postoperative appearance was excellent. It appears that transumbilical resection and umbilical plasty may be a satisfactory operation for POMD.
Humans↗
Ileal atresia associated with an omphalomesenteric duct remnant.
This paper describes an unusual case of ileal atresia associated with an omphalomesenteric duct (OMD) remnant. A 1-day-old male developed bilious vomiting and abdominal distension. At laparotomy, the distal portion of the ileum was connected to the umbilicus with a fibrous band. Around this omphalomesenteric band, the ileum was strangulated and necrotic; the end of the ileum was atretic. Apart from these structures, the cecum terminated without mesentery. This experience shows evidence of an OMD remnant as a possible cause of jejunoileal atresia.
Humans↗
Portal hypertensive enteropathy in biliary atresia.
This paper describes a rare case of biliary atresia (BA) in which massive postoperative bleeding developed due to portal hypertensive enteropathy. A 15-year-old boy had been doing well after Kasai's operation for BA. At around the age of 6 years he developed recurrent episodes of esophageal variceal bleeding and underwent esophageal transection, splenectomy, sclerotherapy, and embolization of the left gastric vein. At the age of 15 years he suddenly developed abdominal pain, hematemesis, and massive tarry stools. His hemoglobin level was 6.3 g/dl. Endoscopy showed several small, polypoid lesions in the jejunum beyond Treitz' ligament. The source of the bleeding was one of these lesions located in the proximal jejunojejunostomy of the Roux-en-Y loop. Because he had repeated episodes of melena, he underwent partial resection of the jejunum under endoscopic guidance. He has since been free of gastrointestinal (GI) bleeding. From this experience, we conclude that the polypoid lesions of an enteropathy may be a cause of massive GI bleeding in the postoperative portal hypertension of BA.
Adolescent↗
The effect of exposure to negative air ions on the recovery of physiological responses after moderate endurance exercise.
This study examined the effects of negative air ion exposure on the human cardiovascular and endocrine systems during rest and during the recovery period following moderate endurance exercise. Ten healthy adult men were studied in the presence (8,000-10,000 cm-3) or absence (200-400 cm-3) of negative air ions (25 degrees C, 50% humidity) after 1 h of exercise. The level of exercise was adjusted to represent a 50-60% load compared with the subjects' maximal oxygen uptake, which was determined using a bicycle ergometer in an unmodified environment (22-23 degrees C, 30-35% humidity, 200-400 negative air ions.cm-3). The diastolic blood pressure (DBP) values during the recovery period were significantly lower in the presence of negative ions than in their absence. The plasma levels of serotonin (5-HT) and dopamine (DA) were significantly lower in the presence of negative ions than in their absence. These results demonstrated that exposure to negative air ions produced a slow recovery of DBP and decreases in the levels of 5-HT and DA in the recovery period after moderate endurance exercise. 5-HT is thought to have contributed to the slow recovery of DBP.
Adult↗
A new approach to dynamic graciloplasty.
The reestablishment of anal function by transposition of the gracilis muscle, combined with the implantation of electrodes and a neuromuscular stimulator (dynamic graciloplasty), has recently been developed. With this method, the transposed muscle maintains contraction by electrical stimulation to maintain neoanal pressure without fatigue. It is necessary to convert the fatigue-prone gracilis muscle to fatigue-resistant muscle by long-term electrical stimulation (conditioning). In most patients receiving dynamic graciloplasty, the conditioning is accomplished after the transposition. However, conditioning before graciloplasty should reduce the risk of ischemia in the transposed muscle after the graciloplasty and improve the outcome. This new sequence of procedures is described, in combination with J-pouch construction, in a patient who required abdominoperineal excision of the rectum for lower rectal cancer. The graciloplasty was performed after conditioning of the gracilis muscle in situ; the conditioning did not cause the patient discomfort and resulted in good anal function.
Adenocarcinoma↗
Colonoscopic diagnosis of lymphoid hyperplasia causing recurrent intussusception: report of a case.
This paper describes a 6-year-old boy with recurrent ileocecal intussusception due to lymphoid hyperplasia in the terminal ileum, which was diagnosed preoperatively by colonoscopy. At the age of 3 years, he developed diarrhea and a tender abdominal mass. He was diagnosed as having intussusception by ultrasound and was treated by hydrostatic barium enema. After resolution, he had three recurrent episodes of intussusception. A contrast barium enema revealed a small mass in the ileocecal region. Colonoscopy showed several exaggerated folds of the terminal ileum and a biopsy showed lymphoid hyperplasia. Because the repeated intussusception seemed to have been caused by the lymphoid hyperplasia in the terminal ileum, he underwent an ileocecal resection without any subsequent recurrence. Based on the above findings, we conclude that a colonoscopy may thus be useful both for diagnosing lymphoid hyperplasia in the terminal ileum as a cause of recurrent intussusception and for deciding how to manage it.
Child↗
Preventive effects of an antiallergic drug, pemirolast potassium, on restenosis after percutaneous transluminal coronary angioplasty.
BACKGROUND: We recently confirmed that pemirolast potassium, an antiallergic agent, markedly inhibits migration and proliferation of vascular smooth muscle cells. It has also been reported that pemirolast inhibits intimal hyperplasia in animal experiments. METHODS AND RESULTS: To elucidate the preventive effects of pemirolast on restenosis after percutaneous transluminal coronary angioplasty (PTCA), 227 patients were enrolled in this prospective, randomized trial. A total of 205 patients who were compatible with the protocol were analyzed (pemirolast group, 104 patients with 140 lesions; control group, 101 patients with 133 lesions). Patients in the pemirolast group received 20 mg/d of pemirolast from 1 week before PTCA until the time of follow-up angiography (4 months after PTCA). Angiographic restenosis was defined as diameter stenosis >/=50% at follow-up. Restenosis rates were significantly lower in the pemirolast group than in the control group (24.0% vs 46.5% of patients, 18.6% vs 35.3% of lesions, P <.01, respectively). During 8 months of follow-up, there were no coronary events (death, myocardial infarction, coronary artery bypass surgery, or repeated PTCA) in 81.7% of the pemirolast group and in 63.4% of the control group (P =.013). CONCLUSIONS: This study suggested that pemirolast would be useful in the clinical setting to prevent restenosis after PTCA.
Aged↗
Vena cava occlusion with balloon to control blood pressure during deployment of transluminally placed endovascular graft.
Transluminally placed endovascular graft (TPEG) replacement has been applied to treat various aortic diseases. At the moment of deployment, TPEG receives a pressure pulse force to shove it distally, which possibly results in misplacement. Moreover, deploying the TPEG in the aorta increases cardiac afterload, which may damage myocardial function. To avoid these risks, we developed a new technique to control blood pressure by almost complete venous return occlusion. Two occlusion balloon catheters are inserted into the superior and inferior vena cava via the femoral vein. TPEG is deployed at the proper position during inflation of the vena cava balloon to maintain a blood pressure as low as 60 mm Hg by cardiac preload blockage. We, thus far, have not experienced even a trivial sequela with this technique.
Aortic Diseases↗
Combined resection of abdominal aorta and inferior vena cava for retroperitoneal rhabdomyosarcoma invading the aortoiliac bifurcation.
The authors report on an 11-year-old boy with retroperitoneal alveolar rhabdomyosarcoma at the aortoiliac bifurcation. The tumor was resected en bloc together with the infrarenal abdominal aorta and the inferior vena cava. The aortic defect was repaired successfully with a Y-shaped Dacron graft. The authors conclude that tumor resection with aortic reconstruction can be a choice for unresectable retroperitoneal tumors in children.
Aorta, Abdominal↗
Characterization of antihistamines using biphasic cutaneous reaction in BALB/c mice.
Effects of 11 histamine H1 receptor antagonists on IgE-mediated biphasic cutaneous reaction in mice were examined. The immediate phase reaction (IPR) assessed at 1 hour after antigen application was significantly inhibited by all antihistamines examined. The inhibition of IPR by cetirizine and mequitazine were potent, but those by cyproheptadine and diphenhydramine were weak. The later phase reaction (LPR) assessed at 24 hours after antigen application was inhibited by chlorpheniramine, oxatomide, ketotifen, mequitazine, emedastine, terfenadine and azelastine. The inhibition of LPR by emedastine was potent, but those by ketotifen and terfenadine were only partial. Emedastine inhibited both IPR and LPR comparably. Present results indicate that H1 receptor activation is involved in the IPR of the biphasic cutaneous reaction, and that the blockade of H1 receptors at IPR does not contribute to the attenuation of following LPR. Histamine H1 receptor antagonists inhibiting the LPR have a property distinct from H1 receptor antagonism, which may have an additional benefit for the treatment of allergic diseases.
Animals↗
Isolation and characterization of vanadium bromoperoxidase from a marine macroalga, Ecklonia stolonifera.
The bromoperoxidase has been isolated from the marine brown alga, Ecklonia stolonifera (83 kDa) and has been characterized. Bromoperoxidase requires vanadium for enzyme activity as has been evidenced by EPR spectroscopy. The enzyme activity increased ca. 250% with the action of V5+ on the isolated enzyme, since more than 2/3 of the protein molecules were in the apo form. The increase in the enzyme activity was specific to V5+, while Fe2+, Fe3+, and Cu2+ inhibited the enzyme activity. This effect of V5+ addition was inhibited in phosphate buffer, probably because phosphate and vanadate compete for the active site. The bromoperoxidase exhibited a high thermostability (Tm = 68 degrees C) and a high stability in organic solvents (completely intact even in the presence of 50% methanol, ethanol and 1-propanol).
Chromatography, Gel↗
Radiotherapy for locoregional recurrent tumors after resection of non-small cell lung cancer.
Thirty-two patients with locoregional recurrence without documented distant metastasis after resection of non-small cell lung cancer were treated with radiotherapy. There were 29 male patients and three female patients. The age range was 49-79 years (median 66 years). Twenty patients had squamous cell carcinoma, 11 patients adenocarcinoma and one patient large cell carcinoma. Ten patients had bronchial stump recurrence alone, 14 patients bronchial stump recurrence with mediastinal and/or supraclavicular fossa lymph nodes recurrence, and eight patients mediastinal and/or supraclavicular fossa lymph nodes recurrence without bronchial stump recurrence. The total dose delivered ranged from 47.5 to 65 Gy. We achieved good results on improving on subjective complaints. Eighty-nine percent (17/19) of patients indicated subjective improvement. Eight of 32 (25%) patients showed a complete response, and 13 of 32 (40.6%) patients showed a partial response. Only one of seven patients (14.3%) with less than 60 Gy showed a complete response, but seven of 25 patients (28%) with 60 Gy and more showed a complete response. The survival rate was 56.2% at 1 year and 12.5% at 5 years. Four patients have survived more than 5 years. The survival rate of the patients with complete response was 50% at 3 and 5 years, that of the patients with non-complete was 12.5% at 3 years and 0% at 5 years (Cox-Mantel test, P < 0.05). In conclusion, high-dose radiotherapy for locoregional recurrent tumors after resection was effective for palliation and improved survival.
Aged↗