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31.
Comparing the hypothalamic and extrahypothalamic actions of endogenous hyperleptinemia 总被引:4,自引:0,他引:4
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32.
Stimulus and site specific induction of hiccups in the oesophagus
of normal subjects 总被引:1,自引:0,他引:1
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Background—Hiccups that are induced by a largemeal have been suggested to result from gastric overdistension. Therole of the oesophagus in precipitating hiccups has never been defined.
Aims—To determine the involvement of oesophagealmechanoreceptors in the hiccup reflex.
Methods—Ten normal healthy subjects wereprospectively evaluated at a university affiliated hospital. Controlledinflation of a polyethylene bag in the proximal and distal oesophaguswas carried out using slow ramp and rapid phasic distensions, by an electronic distension device.
Results—Hiccups were induced in four subjects onlyduring rapid phasic distensions and only in the proximal oesophagus.The mean (SEM) minimal volume threshold for the hiccup reflex was 32.5 (4.8) ml, which was above the perception threshold. Hiccups appearedduring inflation and resolved after deflation.
Conclusions—Sudden rapid stretch of themechanoreceptors in the proximal oesophagus can trigger the hiccupreflex in normal subjects. Only rapid distensions above a determinedvolume threshold will predictably induce hiccups in a given subject.This mechanism may play a role in the physiological induction of hiccups.
Aims—To determine the involvement of oesophagealmechanoreceptors in the hiccup reflex.
Methods—Ten normal healthy subjects wereprospectively evaluated at a university affiliated hospital. Controlledinflation of a polyethylene bag in the proximal and distal oesophaguswas carried out using slow ramp and rapid phasic distensions, by an electronic distension device.
Results—Hiccups were induced in four subjects onlyduring rapid phasic distensions and only in the proximal oesophagus.The mean (SEM) minimal volume threshold for the hiccup reflex was 32.5 (4.8) ml, which was above the perception threshold. Hiccups appearedduring inflation and resolved after deflation.
Conclusions—Sudden rapid stretch of themechanoreceptors in the proximal oesophagus can trigger the hiccupreflex in normal subjects. Only rapid distensions above a determinedvolume threshold will predictably induce hiccups in a given subject.This mechanism may play a role in the physiological induction of hiccups.
Keywords:hiccups; oesophageal mechanoreceptors; electronicdistension device; phasic distension; ramp distension; perceptionthresholds
相似文献33.
Sylvia T. Singer Frans Kuypers Jeffery Fineman Ginny Gildengorin Sandra Larkin Nancy Sweeters Howard Rosenfeld Gregory Kurio Annie Higa Michael Jeng James Huang Elliott P. Vichinsky 《Annals of hematology》2014,93(7):1139-1148
A high tricuspid regurgitant jet velocity (TRV) signifies a risk for or established pulmonary hypertension (PH), which is a serious complication in thalassemia patients. The underlying pathophysiology in thalassemia subgroups and potential biomarkers for early detection and monitoring are not well defined, in particular as they relate to spleen removal. To better understand some of these unresolved aspects, we examined 76 thalassemia patients (35 non-transfused), 25 splenectomized non-thalassemia patients (15 with hereditary spherocytosis), and 12 healthy controls. An elevated TRV (>2.5 m/s) was found in 25/76 (33 %) of the patients, confined to non-transfused or those with a late start of transfusions, including patients with hemoglobin H-constant spring, a finding not previously described. These non or late-transfused patients (76 % splenectomized) had significantly increased platelet activation (sCD40L), high platelet count, endothelial activation (endothelin-1), and hemolysis (LDH, plasma-free Hb), while hypercoagulable and inflammatory markers were not significantly increased. The same markers were increased in the seven patients with confirmed PH on cardiac catheterization, suggesting their possible role for screening patients at risk for PH. A combination of hemolysis and absence of spleen is necessary for developing a high TRV, as neither chronic hemolysis in the non-splenectomized thalassemia patients nor splenectomy without hemolysis, in the non-thalassemia patients, resulted in an increase in TRV. 相似文献
34.
Takako Taniguchi Ayumi Sekiya Mariko Higa Yuji Saeki Kazumi Umeki Akihiko Okayama Tetsuya Hayashi Naoaki Misawa 《Journal of clinical microbiology》2014,52(1):95-102
Helicobacter cinaedi infection is recognized as an increasingly important emerging disease in humans. Although H. cinaedi-like strains have been isolated from a variety of animals, it is difficult to identify particular isolates due to their unusual phenotypic profiles and the limited number of biochemical tests for detecting helicobacters. Moreover, analyses of the 16S rRNA gene sequences are also limited due to the high levels of similarity among closely related helicobacters. This study was conducted to evaluate intact-cell mass spectrometry (ICMS) profiling using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) as a tool for the identification of H. cinaedi. A total of 68 strains of H. cinaedi isolated from humans, dogs, a cat, and hamsters were examined in addition to other Helicobacter species. The major ICMS profiles of H. cinaedi were identical and differed from those of Helicobacter bilis, which show >98% sequence similarity at the 16S rRNA sequence level. A phyloproteomic analysis of the H. cinaedi strains examined in this work revealed that human isolates formed a single cluster that was distinct from that of the animal isolates, with the exception of two strains from dogs. These phyloproteomic results agreed with those of the phylogenetic analysis based on the nucleotide sequences of the hsp60 gene. Because they formed a distinct cluster in both analyses, our data suggest that animal strains may not be a major source of infection in humans. In conclusion, the ICMS profiles obtained using a MALDI-TOF MS approach may be useful for the identification and subtyping of H. cinaedi. 相似文献
35.
Akira Yokote Yuka Hayashi Shozaburo Yanamoto Shinsuke Fujioka Kazuo Higa Yoshio Tsuboi 《Internal medicine (Tokyo, Japan)》2022,61(5):633
Objective Leg muscle strength (LMS) is decreased in early-stage Parkinson disease (PD) patients and is associated with slower walking and falls. However, LMS in advanced PD has not been well investigated. The purpose of this study was to evaluate LMS in advanced PD patients and its effects on gait performance, activities of daily living, and the cognitive function. Methods The medical records of 132 patients with idiopathic advanced PD [Hoehn and Yahr (H&Y) stages 3 and 4] with a mean disease duration of 9.6 years were retrospectively reviewed. Leg extensor muscle strength of the patients was measured using a Strength Ergo 240. The associations between the LMS and gait performance, Barthel index, H&Y stage, and Mini-Mental State Examination (MMSE) score were analyzed. Results A Spearman''s correlation analysis showed that LMS was correlated with the sex, age, age of disease onset, H&Y stage, Barthel index, MMSE score, and gait parameters. A multivariable linear regression analysis for identifying predictors of LMS showed that the gait velocity (β=0.377), Barthel index (β=0.281), sex (β=-0.187), and disease duration (β=-0.155) were significant. A receiver operating characteristic curve analysis for discriminating between H&Y stage 3 and 4 was performed for LMS; the area under the curve was 0.774 (95% confidence interval=0.696-0.851). Conclusions LMS was strongly associated with multiple domains of clinical characteristics, especially gait velocity and the Barthel index. Our study also suggested that LMS can be a predictor of PD progression. 相似文献
36.
J Breslau A Starr N Sicotte J Higa M S Buchsbaum 《Electroencephalography and clinical neurophysiology》1989,72(4):281-289
EEG topography was compared in patients with senile dementia of the Alzheimer's type (SDAT), aged normal controls, and young normal controls to assess regional differences. The square root of absolute power was determined for each frequency using a Fast Fourier Transform (FFT). The normal elderly group showed a reduction in all 4 frequency bands, delta, theta, alpha and beta, at each of 32 leads when compared to the young controls. Z-transformation of the data revealed differences in topography. Older normals showed significantly greater mid-parietal and left mid-temporal delta than the younger controls. A similar pattern was seen for theta activity. Elderly controls showed relatively less occipital alpha and greater mid-parietal alpha. Beta activity demonstrated these same significant topographic differences. The elderly/SDAT comparison was significant for delta only. SDAT patients were characterized by a marked delta asymmetry in temporal regions which was not seen in the elderly normals. 相似文献
37.
Masayuki Higa Tohru Ohnuma Hitoshi MaeshimaTokiko Hatano Ryo HanzawaNobuto Shibata Yoshie SakaiToshihito Suzuki Heii Arai 《Neuroscience letters》2010
Antipsychotic-induced extrapyramidal symptoms (AIEPSs) are commonly recognized side effects of typical 1st generation antipsychotics, and considerable variability is seen in the susceptibility of individual patients to AIEPSs. Regulator of G-protein signaling 2 (RGS2) proteins regulate intracellular signaling and second messenger activation of molecules including dopamine, serotonin, and acetylcholine receptors, all of which appear to be involved in the pathophysiology of AIEPSs. Previous studies have shown an association between AIEPSs in schizophrenia and RGS2, especially the minor G allele of single nucleotide polymorphism (SNP) rs4606 (+2971C > G) in RGS2, and have suggested a possible protective effect by the G allele on AIEPSs. In this study, we investigated whether the rs4606 SNP in RGS2 alone also showed an effect on AIEPSs by utilizing the Drug-Induced Extrapyramidal Symptom Scale (DIEPSS) in 103 Japanese patients with schizophrenia. In the assumed G allele recessive model, sialorrhea and total Parkinsonism scores were significantly higher in subjects with the GG genotype than in subjects with other genotypes. Other clinical variables were not significantly different among the various genotype groups. Controlling for clinical variables as covariates, a one-way analysis of covariance found no association between rs4606 genotypes and DIEPSS scores. Taken together, these results, although preliminary, suggest that rs4606 does not affect AIEPSs in Japanese subjects. 相似文献
38.
Gláucia Andréia Soares Guelsin Ana Maria Sell Lilian Castilho Viviane Lika Masaki Fabiano Cavalcante Melo Margareth Naomi Hashimoto Tatiana Takahashi Higa Loide Souza Hirle Jeane Eliete Laguila Visentainer 《Journal of clinical laboratory analysis》2010,24(5):311-316
We evaluated the usefulness of blood group genotyping as a supplement to hemagglutination to determine the red blood cell (RBC) antigen profile of polytransfused patients with hematological diseases and renal failure. Seventy‐nine patients were selected. They all received more than three units of blood and eight (10%) had already clinical significant alloantibodies occurring alone or in combination against Rh, K, Fya, and Di antigens. DNA was prepared from blood samples and RHCE*E/e, KEL*01/KEL*02, FY*01/FY*02 and JK*01/JK*02 alleles were determined by using PCR‐RFLP. RHD*/RHD*Ψ and RHCE*C/c were tested using multiplex PCR. Discrepancies for Rh, Kell, Duffy, and Kidd systems were found between the phenotype and genotype‐derived phenotype in 16 of the 38 chronically transfused patients. The genotypes of these patients were confirmed by DNA array analysis (HEA Beadchip?; Bioarray Solutions, Warren, NJ). Genotyping was very important for the determination of the true blood groups of the polytransfused patients, helped in the identification of suspected alloantibodies and in the selection of antigen‐negative RBCs for transfusion. J. Clin. Lab. Anal. 24:311–316, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
39.
Cyclotheonamide E4 and E5, new potent tryptase inhibitors from an Ircinia species of sponge 总被引:1,自引:0,他引:1
Murakami Y Takei M Shindo K Kitazume C Tanaka J Higa T Fukamachi H 《Journal of natural products》2002,65(3):259-261
Tryptase is a protease released from mast cells and is believed to contribute to the inflammatory process in allergic diseases including asthma. In the course of screening to find tryptase inhibitors, we isolated two new tryptase inhibitors, cyclotheonamide E4 (3) and E5 (4), from a marine sponge of the genus Ircinia. The structures of these molecules were determined by interpretation of 1H and 13C NMR spectra, and they were shown to be closely related to the previously reported cyclotheonamides E (1), E2, and E3 (2). These molecules contain two unusual amino acids, vinylogous tyrosine and alpha-ketohomoarginine, which are involved in strong activities against serine proteases. Cyclotheonamide E4 showed potent inhibitory activity against human tryptase (IC50 5.1 nM). Therefore, cyclotheonamide E4 may be useful as a therapeutic agent in the treatment of allergic diseases including asthma. 相似文献
40.
Liu TY Tai CT Lee PC Hsieh MH Higa S Ding YA Chen SA 《Journal of cardiovascular electrophysiology》2003,14(5):533-539
INTRODUCTION: Information about the activation patterns inside the superior vena cava (SVC) and entry and exit sites at the SVC-right atrial (RA) junction during SVC tachyarrhythmia is limited. METHODS AND RESULTS: A detailed characterization of electrophysiologic mechanisms and ablation strategies was performed using a noncontact three-dimensional mapping system in two cases of SVC tachycardia. The first case demonstrated SVC tachycardia originating from an ectopic focus inside the SVC, with sustained depolarization and conduction to the atrium. Entry and exit sites across the SVC-RA junction were located very close to each other. The second case demonstrated two different reentrant circuits, one inside the SVC and the other into and out of the SVC-RA junction. The entry and exit sites were located far away from each other. CONCLUSION: Noncontact mapping may help to reveal the mechanism of SVC tachyarrhythmias and to locate entry and exit sites at the SVC-RA junction as a guide for catheter ablation. 相似文献