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31.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
32.
Ito Y Yoshida H Tomoda C Miya A Kobayashi K Matsuzuka F Yasuoka H Kakudo K Inohara H Kuma K Miyauchi A 《Pathology》2005,37(4):296-298
AIMS: Galectin-3, a member of the beta-galactoside binding family of lectins, has been regarded as a useful tool for discriminating malignant tumours from benign nodules of the thyroid, including the distinction between follicular carcinoma and adenoma. However, there are follicular tumours with unclear vascular or capsular invasion, which makes diagnosis more difficult. In this study, we investigated the relationship between galectin-3 expression and the degree of vascular or capsular invasion of follicular tumours. METHODS: We immunohistochemically investigated galectin-3 expression in 260 cases of follicular tumour with various degrees of vascular or capsular invasion classified into four categories. RESULTS: The galectin-3 expression level significantly increased with the degree of vascular or capsular invasion (p<0.0001). However, its diagnostic value for follicular carcinoma was not high because the sensitivity and specificity were 68.7% and 57.5%, respectively. CONCLUSIONS: Our findings suggest that galectin-3 plays a role in the transformation of follicular tumours from benign to malignant; however, when diagnosing follicular tumours, the presence of this protein should not be required for diagnosing malignant transformation in all cases. Therefore, we must conclude that galectin-3 should only be considered an adjuvant marker for follicular carcinoma. 相似文献
33.
Analysis of Host Cells Associated with the Spv-Mediated Increased Intracellular Growth Rate of Salmonella typhimurium in Mice 总被引:4,自引:0,他引:4 下载免费PDF全文
Paul A. Gulig Thomas J. Doyle Jeffrey A. Hughes Hidenori Matsui 《Infection and immunity》1998,66(6):2471-2485
The 90-kb virulence plasmid of Salmonella typhimurium encodes five spv genes which increase the growth rate of the bacteria within host cells within the first week of systemic infection of mice (P. A. Gulig and T. J. Doyle, Infect. Immun. 61:504–511, 1993). The presently described study was aimed at identifying the host cells associated with Spv-mediated virulence by manipulating the mouse host and the salmonellae. To test the effects of T cells and B cells on the Spv phenotype, salmonellae were orally inoculated into nude and SCID BALB/c mice. Relative to normal BALB/c mice, nude and SCID BALB/c mice were unaffected for splenic infection with either the Spv+ or Spv− S. typhimurium strains at 5 days postinoculation. When mice were pretreated with cyclophosphamide to induce granulocytopenia, there was a variable increase in total salmonella infection, but the relative splenic CFU of Spv+ versus Spv− S. typhimurium was not changed after oral inoculation. In contrast, depletion of macrophages from mice by treatment with cyclophosphamide plus liposomes containing dichloromethylene diphosphate resulted in equivalent virulence of Spv+ and Spv− salmonellae. To examine if the spv genes affected the growth of salmonellae in nonphagocytic cells, an invA::aphT mutation was transduced into Spv+ and Spv− S. typhimurium strains. InvA− Spv+ salmonellae were not significantly affected for splenic infection after subcutaneous inoculation compared with the wild-type strain, and InvA− Spv− salmonellae were only slightly attenuated relative to InvA+ Spv− salmonellae. Invasion-defective salmonellae still exhibited the Spv phenotype. Therefore, infection of nonphagocytes is not involved with the Spv virulence function. Taken together, these data demonstrate that macrophages are essential for suppressing the infection by Spv− S. typhimurium, by serving as the primary host cell for Spv-mediated intracellular replication and possibly by inhibiting the replication of salmonellae within other macrophages. 相似文献
34.
Lon,a stress-induced ATP-dependent protease,is critically important for systemic Salmonella enterica serovar typhimurium infection of mice 下载免费PDF全文
Takaya A Suzuki M Matsui H Tomoyasu T Sashinami H Nakane A Yamamoto T 《Infection and immunity》2003,71(2):690-696
Studies on the pathogenesis of Salmonella enterica serovar Typhimurium infections in mice have revealed the presence of two prominent virulence characteristics-the invasion of the nonphagocytic cells to penetrate the intestinal epithelium and the proliferation within host phagocytic cells to cause a systemic spread and the colonization of host organs. We have recently demonstrated that the ATP-dependent Lon protease of S. enterica serovar Typhimurium negatively regulates the efficiency of invasion of epithelial cells and the expression of invasion genes (A. Takaya et al., J. Bacteriol. 184:224-232, 2002). This study was performed to reveal the contribution of the Lon protease to the virulence of S. enterica serovar Typhimurium in mice. Determination of 50% lethal doses for the lon disruption mutant and wild-type strain revealed that the mutant was highly attenuated when administered either orally or intraperitoneally to BALB/c mice. The mutant was also found to be able to reach extraintestinal sites but unable to proliferate efficiently within the spleen and cause lethal systemic disease of mice. Macrophage survival assays revealed that the lon disruption mutant could not survive or proliferate within murine macrophages. In addition, the mutant showed extremely increased susceptibility to hydrogen peroxide, which contributes to the bactericidal capacity of phagocytes. The mutant also showed increased sensitivity to acidic conditions. Taken together, the impaired ability of the lon disruption mutant to survive and grow in macrophages could be due to the enhanced susceptibility to the oxygen-dependent killing mechanism associated with respiratory burst and the low phagosomal pH. These results suggest that the Lon protease is essentially involved in the systemic infection of mice with S. enterica serovar Typhimurium, which can be fatal. Of further interest is the finding that the lon disruption mutant persists in the BALB/c mice for long periods without causing an overwhelming systemic infection. 相似文献
35.
Defective interleukin-1 production in a familial monocyte disorder with a combined abnormality of mobility and phagocytosis-killing. 下载免费PDF全文
A Komiyama M Ichikawa H Kanda K Aoyama K Yasui M Yamazaki H Kawai Y Miyagawa T Akabane 《Clinical and experimental immunology》1988,73(3):500-504
Monocytes in a familial monocyte disorder, a recently recognized primary immunodeficiency syndrome, with impaired phagocytic functions were studied for their ability to produce interleukin 1 (IL-1) as well as the surface property. Monocytes from two children (siblings) with the disorder possessed CD11b, CD13, CD14, CD33, Ia and LFA-1/Mac-1/p150,95 beta subunit antigens as determined by flow cytometry. Electron microscopic cytochemistry showed that the monocytes had surface glycoproteins reactive with four representative lectins. The IL-1 production by monocytes was assayed in the two patients and compared with that in six children with primary immunodeficiency syndromes and some monocyte abnormalities; three had congenital neutropenia, two had hyper-IgE syndrome, and one had defective monocyte chemotaxis. Monocyte culture supernatants were prepared with stimulation by lipopolysaccharide or silica, and their IL-1 activity was measured by the mouse thymocyte-proliferation assay. The patients' monocytes were defective in IL-1 production: the values were less than 1.0% of the control monocyte values (n = 12) and were in contrast with those of congenital neutropenia monocytes of 186.2% to 204.3%. These results demonstrate a familial monocyte disorder which is characteristic among the immunodeficiency syndromes with regard to the defective IL-1 production and the impaired phagocytic functions. 相似文献
36.
Role of sialic acid in saliva-mediated aggregation of Pseudomonas aeruginosa isolated from cystic fibrosis patients. 总被引:2,自引:4,他引:2 下载免费PDF全文
The mechanism of saliva-mediated aggregation of Pseudomonas aeruginosa in subjects with and without cystic fibrosis (CF) was investigated. Virtually all saliva from CF patients that we tested strongly agglutinated the Pseudomonas cells and was heat stable to 56 degrees C, whereas saliva from subjects without CF had a decreased aggregating ability and was heat sensitive. When saliva was treated with neuraminidase and proteases, and also when P. aeruginosa cells were treated with mixed gangliosides, there was a decrease in aggregating activities. However, neither the addition of the acid-hydrolyzed ganglioside nor the treatment of the P. aeruginosa cells by sugars had any effect on subsequent aggregating activities. Therefore, the release of sialic acid by enzymatic treatments of saliva, as well as the blockage of the sialic acid-binding sites on the cell wall by mixed gangliosides, resulted in the parallel loss of saliva-mediated aggregating activity of P. aeruginosa. The level of free sialic acid released by endogenous neuraminidase was higher in the saliva from CF patients than in that from the non-CF subjects examined. The increased aggregation of P. aeruginosa mediated by saliva from patients with CF seems to be directly related to the sialic acid content present, suggesting that this acid molecule acts as the salivary receptor for P. aeruginosa. 相似文献
37.
The hippocampus is important in learning and memory functions but its ability to aid in these functions declines during aging. In this study, we examined hippocampal proteins whose expressions changed in the aging process. A comparison of synaptosome proteins of hippocampus prepared from young-adult (9-week-old) rats with those from aged (30-month-old) rats by two-dimensional fluorescence difference gel electrophoresis revealed 24 spots that were expressed differently among about 1000 spots detected in both young-adult and aged rat samples. Nineteen of these 24 spots were identified by peptide mass fingerprinting. These proteins included chaperone proteins and proteins related to the cytoskeleton, neurotransmission, signal transduction and energy supply. The cytoskeleton-related proteins included actin and T-complex 1, which is thought to play a role in actin folding. Actin was up-regulated but T-complex 1 was down-regulated in aged rat synapses. These results suggest that age-dependent changes of actin filament formation are related to neuronal dysfunction associated with aging. 相似文献
38.
Hidenori Nonaka Minoru Tanaka Kaori Suzuki Atsushi Miyajima 《Developmental dynamics》2007,236(8):2258-2267
Endothelial cells (ECs) display distinct structural and functional characteristics depending on the tissue and developmental stage; however, the development of tissue-specific ECs remains poorly understood. Here, we describe the development of hepatic sinusoids in mice based on the expression of hyaluronan receptors Stab2 and Lyve-1. Flk-1(+) cells in and around the liver bud begin to express Stab2 at embryonic day (E) 9.5, before the formation of vascular lumen. Hepatic sinusoidal endothelial cells (HSECs) begin to express Lyve-1 at E10.5, and both markers continue to be expressed in HSECs thereafter. Although HSECs and lymphatic ECs (LECs) are known to share functional and phenotypic characteristics, we clearly show that HSECs can be distinguished from LECs by the expression of molecular markers and higher endocytotic activity. Our results provide new insight into the development of tissue-specific ECs and phenotypic criteria to distinguish HSECs from other types of ECs, including LECs. 相似文献
39.
Emiko Ono Yuji Maeda Hidenori Tanimoto Yuma Fukutomi Chiyako Oshikata Kiyoshi Sekiya Takahiro Tuburai Naomi Turikisawa Mamoru Otomo Masami Taniguchi Houta Ishii Akihiko Asahina Eishi Miyazaki Tosihide Kumamoto Kazuo Akiyama 《Arerugī》2007,56(6):587-592
BACKGROUND: Recently, it is recognized that the patients of oral allergy syndrome (OAS) to fruits are increasing. However, there are little knowledges of the background, character, and seriousness about these patients in Kanto regions. OBJECTIVE: We aimed to investigate the clinical features of OAS patients to plant origin foods in Kanto regions. METHODS: The patient, who visited Sagamihara National Hospital from 2000 to 2005 and developed some allergic symptoms to plant origin foods, were studied by a questionary survey. RESULTS: As for the 42 subjects, average age are 36 years old, male:female=8:34, merger of other allergic disease is 35 allergic rhinitis of 42 subjects (83%), 34 of asthma (81%), 14 of atopic dermatitis (33%). The causes of OAS symptoms are 32 rose-family fruits, 34 non-rose family fruits, 14 vegetables, 11 nuts, 2 grains subjects. As for the symptom, only in the oral and pharynx symptoms are found in 12, the systemic symptoms is 29, anaphylaxis is 11 subjects. Allergic rhinitis preceded on the 90% subjects with pollinosis, very high rate. On the other hand, the 20% of all subjects have no symptoms of allergic rhinitis. CONCLUSION: A nasal catarrh symptoms went ahead in most of the OAS subjects in Kanto regions. In addition, considering from some patients have no black alder pollinosis and/or are allergic to many non-rose-family fruits at high frequency, there might be a broad cross-reactivity between many pollens other than alder and plant origin foods. 相似文献
40.
Kazuya Takeda Shuhei Sakakibara Kazuo Yamashita Daisuke Motooka Shota Nakamura Marwa Ali El Hussien Jun Katayama Yohei Maeda Masanobu Nakata Shigeyuki Hamada Daron M. Standley Masaki Hayama Takashi Shikina Hidenori Inohara Hitoshi Kikutani 《The Journal of allergy and clinical immunology》2019,143(3):1163-1175.e15