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991.
992.
993.
Yuko Nishi Nobuo Kitamura Masayuki Otani Eiichi Hondo Kiyoshi Taguchi Junzo Yamada 《Annals of anatomy》2000,182(4):319-326
The distribution of nerve fibers immunoreactive for substance P (SP) and calcitonin gene-related peptide (CGRP) was examined by means of immunohistochemical methods in the respiratory tract from nose to lung of normal and capsaicin-treated cattle. SP- and CGRP-immunoreactive (IR) nerve fibers with varicosities were detected in all portions. They were more numerous in calves than in cows. They were abundant in the nasal and laryngeal mucosae and tracheal bronchus, and few in number in the lung. SP- and CGRP-IR nerve fibers were mainly seen in the epithelium, in connective tissue beneath the epithelium and around blood vessels, and in the glands throughout the respiratory tract. In contrast, SP- and CGRP-IR nerve fibers were sparse in the smooth muscle layer. Capsaicin treatment of neonates caused a remarkable reduction in the number of SP- and CGRP-IR nerve fibers in the respiratory tract of calves. Double immunofluorescence experiments showed the colocalization of SP and CGRP in most of the nerve fibers. The present findings suggest that SP- and CGRP-IR nerve fibers are involved in the regulation of the bovine respiratory tract, and that capsaicin-sensitive SP- and CGRP-IR nerve fibers are sensory neurons of the bovine respiratory tract. 相似文献
994.
Shimizu K Fujii S Fujimoto K Kawa K Yamada A Kawano F 《Journal of leukocyte biology》2000,68(5):633-640
The macrolide lactone, tacrolimus (FK506), is utilized in bone marrow transplantation (BMT) to prevent graft-versus-host disease (GVHD). In the current study, we evaluated the ability of FK506 to modify the function of dendritic cells (DCs) derived from CD34+ hematopoietic progenitor cells (HPCs). Comparable to DCs obtained in the absence of FK506, DCs cultured in the presence of FK506 (FK-DCs) had higher expression of CD1a+ and formed a greater number of DC colonies. Despite the same expression of costimulatory molecules, FK-DCs displayed a reduced capacity to stimulate an allogeneic T cell response, and showed significantly lower interleukin (IL)-12 production. While normal DCs pulsed with the exogenous antigen, keyhole limpet hemocyanin (KLH) induced specific Th1-like interferon-gamma(IFN-gamma) producing CD4+ T cell line, FK-DCs induced Th2-like interleukin-4 (IL-4) producing CD4+ T cell line. These data demonstrate the ability of FK506 to induce Th2-promoting function in developing DCs. 相似文献
995.
996.
Tanaka S Harada M Mine T Noguchi M Gohara R Azuma K Tamura M Yamada A Morinaga A Nishikori M Katagiri K Itoh K Yamana H Hashimoto T 《Journal of immunotherapy (Hagerstown, Md. : 1997)》2003,26(4):357-366
Identification of antigenic peptides expressed on cancer cells enables us to treat cancer patients with peptide-based immunotherapy. Although optimal protocols for peptide-based vaccines have not yet been elucidated, boosting the immune system could be a better approach than priming the immune system to elicit prompt and potent peptide-specific T-cell responses in cancer patients. With this possibility in mind, the authors undertook a clinical trial in which cancer patients were vaccinated with peptides (maximum 4) after confirmation of pre-existing peptide-specific cytotoxic T-lymphocyte (CTL) precursors in the periphery. Fourteen patients (seven with melanoma and seven with other types of cancer) positive for either HLA-A24 or HLA-A2 were enrolled in this study. Fourteen and 16 peptides were used to screen for HLA-A24+ and HLA-A2+ patients, respectively. The vaccination was well tolerated, and the only adverse effects were local pain and fever. Kinetic analysis revealed that peptide-reactive CTLs increased after peptide vaccination in 7 of 14 patients. Immunoglobulin G (IgG) reactive to the administered peptides was detected in 2 patients before vaccination, although it became detectable in 8 of the other 12 patients after the peptide vaccination. Stable disease for more than 6 months was observed in five patients (one with melanoma and four with other types of cancer); all of these patients showed increased levels of peptide-specific IgG. These results indicate that peptide vaccination of patients showing evidence of pre-existing peptide-specific CTL precursors can be applied in further clinical trials aimed at the treatment of melanoma and other types of cancer. 相似文献
997.
The prediction of rapid conversion to Alzheimer's disease in mild cognitive impairment using regional cerebral blood flow SPECT 总被引:13,自引:0,他引:13
Hirao K Ohnishi T Hirata Y Yamashita F Mori T Moriguchi Y Matsuda H Nemoto K Imabayashi E Yamada M Iwamoto T Arima K Asada T 《NeuroImage》2005,28(4):1014-1021
Mild cognitive impairment (MCI) comprises a heterogeneous group with a variety of clinical outcomes and they are at risk for developing Alzheimer's disease (AD). The prediction of conversion from MCI to AD using the initial neuroimaging studies is an important research topic. We investigated the initial regional cerebral blood flow (rCBF) measurements using single photon emission computed tomography (SPECT) in individuals with 76 amnesic MCI (52 subjects converted to AD and 24 subjects did not convert to AD at 3-year follow-up) and 57 age- and gender-matched controls. We sought functional profiles associated with conversion to AD, then evaluated the predictive value of the initial rCBF SPECT. As compared with controls, AD converters demonstrated reduced blood flow in the bilateral parahippocampal gyri, precunei, posterior cingulate cortices, bilateral parietal association areas, and the right middle temporal gyrus. Non-converters also demonstrated significant reduction of rCBF in the posterior cingulated cortices and the right caudate nucleus when compared to controls. As compared with non-converters, converters showed reductions of rCBF in the bilateral temporo-parietal areas and the precunei. The logistic regression model revealed that reduced rCBF in the inferior parietal lobule, angular gyrus, and precunei has high predictive value and discriminative ability. Although a cross-validation study is needed to conclude the usefulness of rCBF SPECT for the prediction of AD conversion in individuals with MCI, our data suggest that the initial rCBF SPECT studies of individuals with MCI may be useful in predicting who will convert to AD in the near future. 相似文献
998.
999.
Anterior cingulate pathology and social cognition in schizophrenia: a study of gray matter, white matter and sulcal morphometry 总被引:1,自引:0,他引:1
Fujiwara H Hirao K Namiki C Yamada M Shimizu M Fukuyama H Hayashi T Murai T 《NeuroImage》2007,36(4):1236-1245
The anterior cingulate gyrus (ACG) is a critical structure for social cognitive processing; the pathology of this structure might be a major source of social dysfunction in schizophrenia. Multiple structural abnormalities of the ACG have been demonstrated in schizophrenia including changes in gray matter volume, white matter microstructures and macroscopic sulcal morphology. However, the interrelationships among these different abnormalities have not been investigated. Thus, the relationship between structural abnormalities in the ACG and social cognition in schizophrenia remains to be elucidated. Magnetic resonance imaging data were acquired at 3.0 T from 26 schizophrenic patients and 20 healthy participants. We performed anterior cingulate cortex (ACC) volumetry, evaluated diffusion tensor imaging of the anterior cingulum, analyzed paracingulate/cingulate sulcus (PCS/CS) morphology and investigated the interrelationships among these measures. We also investigated the association between ACG structural abnormalities and psychopathology, and the social cognition ability of schizophrenic patients as estimated by emotion attribution tasks. Compared with healthy subjects, schizophrenic patients exhibited reduced ACC volume, decreased fractional anisotropy in the anterior cingulum bilaterally and a poorly developed PCS/CS in the left hemisphere. No interrelationship was identified among these measures in the schizophrenic group. Schizophrenic patients performed poorly on emotion attribution tasks. Importantly, clinical symptoms and performance on emotion attribution subtasks were associated with ACC volumes and left PCS/CS variation in different ways. These results suggested that pathology of the ACC, anterior cingulum and PCS/CS is, at least partially, independent and has differential impacts on psychopathology and social cognitive impairment in schizophrenia. 相似文献
1000.
Kusuoka H Yamasaki Y Izumi T Kashiwagi A Kawamori R Shimamoto K Yamada N Nishimura T 《Annals of nuclear medicine》2008,22(1):13-21
Objective Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted
as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon
emission computed tomography (SPECT) of ischemic heart disease.
Methods Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will
be followed for 3 years, stratified by patients’ clinical background and SPECT findings.
Results A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2 ± 0.4 years, mean
± SEM) and 261 women (age 67.8 ± 0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular
disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension
(82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two
of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis,
and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent
SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed
by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress
examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%),
and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received 99mTc-tetrofosmin at an initial dosage of 200–300 MBq (mean 331 ± 3 MBq) followed by a second dosage of 700–800 MBq (mean 748
± 8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were used by the largest number
(83.2%), followed by hypotensive (66.7%), hypolipidemic (40.7%), and antiplatelet drugs (27.7%), vasodilators (5.5%), and
antioxidants and others (2.3%).
Conclusions This study was designed to clarify the correlation between coronary artery disease and diabetes mellitus as its risk factor
based on the clinical and imaging findings. Patient enrollment was closed on September 30, 2005, and follow-up is now under
way. 相似文献