216 research outputs found
Phagocytic response to fully controlled plural stimulation of antigens on macrophage using on-chip microcultivation system
To understand the control mechanism of innate immune response in macrophages, a series of phagocytic responses to plural stimulation of antigens on identical cells was observed. Two zymosan particles, which were used as antigens, were put on different surfaces of a macrophage using optical tweezers in an on-chip single-cell cultivation system, which maintains isolated conditions of each macrophage during their cultivation. When the two zymosan particles were attached to the macrophage simultaneously, the macrophage responded and phagocytosed both of the antigens simultaneously. In contrast, when the second antigen was attached to the surface after the first phagocytosis had started, the macrophage did not respond to the second stimulation during the first phagocytosis; the second phagocytosis started only after the first process had finished. These results indicate that (i) phagocytosis in a macrophage is not an independent process when there are plural stimulations; (ii) the response of the macrophage to the second stimulation is related to the time" delay from the first stimulation. Stimulations that occur at short time intervals resulted in simultaneous phagocytosis, while a second stimulation that is delayed long enough might be neglected until the completion of the first phagocytic process
O-Alkylation of Dihydroxo(tetraarylporphyrinato)phosphorus(V) and Antimony(V) Complexes with Alkyl Halides
The O-alkylation of dihydroxo(tetraarylporphyrinato)phosphorus(V) complexes with several kinds of alkyl bromide in MeCN in the presence of K2CO3 and 18-crown-6 ether produced dialkoxo(tetraarylporphyrinato)phosphorus(V) complexes in-moderate-good yields. Similar O-alkylation was applied to dihydroxo(tetraarylporphyrinato)antimony(V) complexes. The O-alkylation proceeded by the occurrence of an SN2 attack of the alkoxide anion of the complexes at the carbon substituted with halides
Pancreatic tumor insulin responsiveness
The aim : Pancreatic cancer, a rapidly progressive malignancy, is often diagnosed in patients with diabetes. The incidence of pancreatic cancer has risen dramatically over recent decades. Early diagnosis of this malignancy is generally difficult because the symptoms do not become apparent until the disease has progressed, generally leading to a poor outcome. To achieve earlier diagnosis, we analyzed the clinical characteristics of pancreatic cancer patients showing deterioration of plasma glucose levels while hospitalized. Method : Thirty-six cases were divided into 2 groups ; those diagnosed with diabetes more than a year prior to identification of pancreatic cancer and diabetes secondary to pancreatic cancer. These 2 groups were further subdivided according to the tumor site (head or body / tail), allowing analysis of 4 subgroups. Anthropometric measurements, laboratory values were determined. Results : Both groups with diabetes lost at least 4 kg and showed HbA1c deterioration of at least 1% within 5 months of the pancreatic cancer diagnosis. The post-meal elevation of serum C-peptide immunoreactivity (CPR) was significantly decreased in the group with cancer of the pancreatic head, and this was unrelated to tumor size. Conclusion : Characteristically, pancreatic head cancer was associated with decreased endogenous insulin secretion as compared to body / tail cancer
Characterization of Ī±-gustducin
Aims/Introduction: Taste receptors, T1rs and T2rs, and the tasteāselective Gāprotein, Ī±āgustducin, are expressed outside the tasteāsensing system, such as enteroendocrine L cells. Here, we examined whether Ī±āgustducin also affects nutrition sensing and insulin secretion by pancreatic Ī²ācells.
Materials and Methods: The expression of Ī±āgustducin and taste receptors was evaluated in Ī²ācell lines, and in rat and mouse islets either by quantitative polymerase chain reaction or fluorescence immunostaining. The effects of Ī±āgustducin knockdown on insulin secretion and on cyclic adenosine monophosphate and intracellular Ca2+ levels in rat INSā1 cells were estimated. Sucralose (taste receptor agonist)āinduced insulin secretion was investigated in INSā1 cells with Ī±āgustducin suppression and in islets from mouse disease models.
Results: The expression of Tas1r3 and Ī±āgustducin was confirmed in Ī²ācell lines and pancreatic islets. Basal levels of cyclic adenosine monophosphate, intracellular calcium and insulin secretion were significantly enhanced with Ī±āgustducin knockdown in INSā1 cells. The expression of Ī±āgustducin was decreased in highāfat dietāfed mice and in diabetic db/db mice. Sucraloseāinduced insulin secretion was not attenuated in INSā1 cells with Ī±āgustducin knockdown or in mouse islets with decreased expression of Ī±āgustducin.
Conclusions: Ī±āGustducin is involved in the regulation of cyclic adenosine monophosphate, intracellular calcium levels and insulin secretion in pancreatic Ī²ācells in a manner independent of taste receptor signaling. Ī±āGustducin might play a novel role in Ī²ācell physiology and the development of type 2 diabetes
Severe Gastritis after Administration of Nivolumab and Ipilimumab
Immune checkpoint inhibitors such as ipilimumab, a cytotoxic T-lymphocyte-associated antigen-4 inhibitor, have been widely used for advanced malignancies. As these inhibitors improve antitumor immunity via T-cell modulation, immune-mediated adverse events associated with T-cell activation, such as colitis, might occur. Herein, we describe a 75-year-old Japanese woman with metastatic malignant melanoma who developed hemorrhagic gastritis after ipilimumab treatment. There was no macroscopic or clinical improvement of gastritis after proton pump inhibitor treatment. However, her condition improved after approximately 3 weeks of corticosteroid therapy and Helicobacter pylori eradication. This case suggests a potential association between severe gastritis and immune checkpoint inhibitor treatment. Although several reports have mentioned ipilimumab-associated colitis, gastritis is considered to be rare. In the present case, H. pylori-associated gastritis might have been exacerbated by the T-cell modulation effect of ipilimumab. To date, no report has clarified the mechanism by which ipilimumab modifies H. pylori infection. The present treatment course provides a helpful perspective for similar cases
Identification of neuron-type specific promoters in monkey genome and their functional validation in mice
The Relationship between Peripheral Nerve Conduction Velocity and Ophthalmological Findings in Type 2 Diabetes Patients with Early Diabetic Retinopathy
Purpose. Nerve conduction velocity (NCV) is an indicator of neuronal damage in the distal segment of the peripheral nerves. Here, we determined the association between NCV and other systemic and ocular clinical findings, in type 2 diabetes patients with early diabetic retinopathy (DR). Methods. This study included 42 eyes of 42 type 2 diabetes patients (median age: 54 years) with no DR or with mild nonproliferative DR. Standard statistical techniques were used to determine associations between clinical findings. Results. Sural sensory conduction velocity (SCV) and tibial motor conduction velocity (MCV) were significantly lower in mild nonproliferative DR patients than patients with no DR (P=0.008 and P=0.01, resp.). Furthermore, logistic regression analyses revealed that sural SCV and tibial MCV were independent factors contributing to the presence of mild nonproliferative DR (OR 0.83, P=0.012 and OR 0.69 P=0.02, resp.). Tibial MCV was correlated with choroidal thickness (CT) (P=0.01), and a multiple regression analysis revealed that age, tibial MCV, and carotid intima-media thickness were independent associating factors with CT (P=0.035, P=0.015, and P=0.008, resp.). Conclusions. Our findings suggest that reduced NCV may be closely associated with early DR in type 2 diabetes patients. Thus, reduced nerve conduction is a potential early biomarker of DR
Differential gene expression profiles in neurons generated from lymphoblastoid B-cell line-derived iPS cells from monozygotic twin cases with treatment-resistant schizophrenia and discordant responses to clozapine
Schizophrenia is a chronic psychiatric disorder with complex genetic and environmental origins. While many antipsychotics have been demonstrated as effective in the treatment of schizophrenia, a substantial number of schizophrenia patients are partially or fully unresponsive to the treatment. Clozapine is the most effective antipsychotic drug for treatment-resistant schizophrenia; however, clozapine has rare but serious side-effects. Furthermore, there is inter-individual variability in the drug response to clozapine treatment. Therefore, the identification of the molecular mechanisms underlying the action of clozapine and drug response predictors is imperative. In the present study, we focused on a pair of monozygotic twin cases with treatment-resistant schizophrenia, in which one twin responded well to clozapine treatment and the other twin did not. Using induced pluripotent stem (iPS) cell-based technology, we generated neurons from iPS cells derived from these patients and subsequently performed RNA-sequencing to compare the transcriptome profiles of the mock or clozapine-treated neurons. Although, these iPS cells similarly differentiated into neurons, several genes encoding homophilic cell adhesion molecules, such as protocadherin genes, showed differential expression patterns between these two patients. These results, which contribute to the current understanding of the molecular mechanisms of clozapine action, establish a new strategy for the use of monozygotic twin studies in schizophrenia research
Identification of tuberculosis-associated proteins in whole blood supernatant
<p>Abstract</p> <p>Background</p> <p>Biological parameters are useful tools for understanding and monitoring complicated disease processes. In this study, we attempted to identify proteins associated with active pulmonary tuberculosis (TB) using a proteomic approach.</p> <p>Methods</p> <p>To assess TB-associated changes in the composition of human proteins, whole blood supernatants were collected from patients with active TB and healthy control subjects. Two-dimensional difference gel electrophoresis (2D-DIGE) was performed to analyze proteins with high molecular weights (approximately >20 kDa). Baseline protein levels were initially compared between patients with active TB and control subjects. Possible changes of protein patterns in active TB were also compared <it>ex vivo </it>between whole blood samples incubated with <it>Mycobacterium tuberculosis </it>(<it>Mtb</it>)-specific antigens (stimulated condition) and under unstimulated conditions. Immunoblot and enzyme-linked immunosorbent assays (ELISA) were performed to confirm differences in identified proteins.</p> <p>Results</p> <p>Under the baseline condition, we found that the levels of retinol-binding protein 4 (RBP4), fetuin-A (also called Ī±-HS-glycoprotein), and vitamin D-binding protein differed between patients with active TB and control subjects on 2D gels. Immunoblotting results confirmed differential expression of RBP4 and fetuin-A. ELISA results further confirmed significantly lower levels of these two proteins in samples from patients with active TB than in control subjects (<it>P </it>< 0.0001). <it>Mtb</it>-specific antigen stimulation <it>ex vivo </it>altered clusterin expression in whole blood samples collected from patients with active TB.</p> <p>Conclusions</p> <p>We identified TB-associated proteins in whole blood supernatants. The dynamics of protein expression during disease progression may improve our understanding of the pathogenesis of TB.</p
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