Activated CD8(+) T cells from aged mice exhibit decreased activation-induced cell death

To uncouple the defects of activation and apoptosis of T cells from aged mice, we used anti-CD3 plus IL-2 stimulation to induce an activation response and analyzed the subsequent activation-induced cell death (AICD) response of T cells from 16-month-old mice. The results herein demonstrate that T cells from 16-month-old mice could be activated by anti-CD3-induced activation signals but exhibited distinct phenotypic and functional features compared to young (2-month-old) mice. These include a decrease in AICD, a delayed entry into the cell cycle, and a decreased telomerase activity. The decreased AICD of T cells from 16-month-old mice is associated with a decreased expression of Fas and Fas ligand (FasL), decreased susceptibility to anti-Fas-induced apoptosis, and an increased expansion of a CD8(+) T-cell population. Prior to activation, these T cells exhibit a phenotype that is CD44(hi)CD62L(hi). After stimulation, these T cells produced high levels of the pro-inflammatory cytokine, IFN-gamma, and developed an increased population of IFN-gamma(+)IFN-gamma R(-) T cells. Our results suggest that there is a dysregulation in T-cell homeostasis in aged mice associated with a decrease in AICD of CD8(+) T cells.     

Fc receptor-mediated accumulation of macrophages in crescentic glomerulonephritis induced by anti-glomerular basement membrane antibody administration in WKY rats

Anti-glomerular basement membrane (GBM) glomerulonephritis induced in WKY rats is characterized by glomerular accumulation of CD8(+) T cells and monocytes/macrophages, followed by crescent formation. The mechanism of leukocyte accumulation after antibody binding to GBM is still unclear. To unveil an involvement of Fcgamma receptors (FcgammaR) in leukocytes recruitment we examined the expression of FcgammaR in glomeruli and the effects of the administration of F(ab')(2) fragment of anti-GBM antibody or FcgammaR blocking on the initiation and progression of this model. A gradual increase of FcgammaR mRNA expression in glomeruli during the time course of disease suggested their significance in the development of glomerulonephritis. Glomerular lesions and proteinuria were induced only in rats injected with intact IgG of anti-GBM antibody, but not with the F(ab')(2) fragment. In vivo blocking of FcgammaR by administering heat-aggregated IgG led to the decrease of mRNA expression for all types of FcgammaR (types 1, 2 and 3) and a significant amelioration of glomerulonephritis manifestations. By flow cytometry and immunohistochemistry FcgammaR2-expressing cells in glomeruli were identified as macrophages, but not CD8(+) T cells. The expression of FcgammaR1 and 3 was significantly decreased, and that of FcgammaR2 became undetectable in CD8(+) T cell-depleted rats. Thus, CD8(+) T cells may stimulate FcgammaR expression on macrophages, contributing to their glomerular accumulation and injury. These studies provide direct evidence for a crucial involvement of IgG Fc-FcgammaR interaction in glomerular recruitment of macrophages and following induction of anti-GBM glomerulonephritis in WKY rats.     

Polymer conformation and NMR chemical shifts, 6. Alternating copolymer of α-methylene-γ-butyrolactone with styrene

In view of the structural resemblance of α-methylene-γ-butyrolactone to methyl methacrylate, conformation and NMR chemical shifts of poly(α-methylene-γ-butyrolactone-alt-styrene). are calculated and compared with those of poly(methyl methacrylate-alt-styrene). The conformational energy surfaces for the dyad sequence models of the both copolymers are analogous to each other, as is expected from the similarity in the constituting monomeric units. Agreement of calculation with observation is satisfactory with respect to the cotacticity-dependent splittings in the ¹³C NMR spectra and is improved by the fixation of a substituent in poly(α-methylene-γ-butyrolactone-alt-styrene). Calculation of ¹H chemical shifts gives an alignment of NMR signals which is in accordance with the observation.     

Detection of alternatively spliced variant messages of Fas gene and mutational screening of Fas and Fas ligand coding regions in peripheral blood mononuclear cells derived from silicosis patients

Silicosis is clinically characterized not only by respiratory disorders but by immunological abnormalities such as the appearance of autoantibodies and complications of autoimmune diseases. Dysregulation of apoptosis, particularly in the Fas/Fas ligand (FasL) pathway, has been considered to play a role in the pathogenesis of autoimmune diseases. It has been found that serum soluble Fas (sFas) levels are elevated in silicosis patients (SIL) and the sFas message is dominantly expressed in peripheral blood mononuclear cells (PBMC) derived from these individuals. In the present study, one tried to detect alternatively spliced variant messages including typical sFas message and found four that were highly and frequently expressed, and which possess a signal peptide domain, but not transmembrane and signal transducing domains, in PBMC derived from SIL. Functional mutations were not detected in Fas and FasL genes in silicosis PBMC. Still, alternative spliced variants of the Fas gene including typical sFas message appear to play an important role in the immunological dysregulation in SIL.     

Direct sequencing of a HLA-DRB gene by polymerase chain reaction: sequence variation in DRw8 specificity

The nucleotide sequence of a HLA-DRB gene with a predominant subtype of DRw8 specificity in Japanese (DR8.1) was determined with single-stranded DNA enzymatically amplified by polymerase chain reaction (PCR). The sequence differs at a single amino acid from both of the published DRw8/Dw8.1 and DRw8/Dw8.2 sequences: isoleucine67(AUC) instead of phenylalanine67(TTC) in DRw8/Dw8.1 and serine57(AGC) instead of aspartic acid57(GAT) in DRw8/Dw8.2. On the other hand the DR8.1 and DRw8/Dw8.3 have the same amino acid sequence although one silent nucleotide substitution has occurred between the two sequences. These results indicate that Japanese DR8.1 specificity corresponds to DRw8/Dw8.3. Furthermore, an oligonucleotide probe specific for this sequence was synthesized and hybridized with 33 HLA-typed controls. This probe clearly distinguished the particular subtype from other DRw8 subtypes and specificities.     

Hemostatic parameters in newborn--II. Sequential study during the first four weeks of life

A sequential study of kaolin cephalin clotting time (KCCT), prothrombin time (PT), thrombin time (TT), plasma fibrinogen and serum FDP was conducted during the first four weeks of life on term and preterm babies. A "physiological dip" of PT and TT was noted inappropriate for gestational age (AGA) babies both term and preterm; in case of KCCT, the dip was significant in term AGA babies only. At the end of four weeks, PT and TT had moderately improved in term babies but showed little improvement in preterm ones; KCCT reached almost an adult value in all babies except in preterm AGA and term LGA (large for gestational age) ones. Plasma fibrinogen showed no "physiological dip" and reached adult level in two to four weeks. Serum FDP levels were appreciably raised in preterm AGA babies only at birth and there too normalised by 72 h.     

Ghrelin after chemotherapy as a prognostic predictor of progression-free survival in patients with muscle-invasive bladder cancer

BackgroundAlthough the patients with muscle-invasive bladder cancer (MIBC) generally have poor prognosis, the utility of these biomarkers for the prediction of oncological outcomes in MIBC has not been completely explored. Ghrelin regulates processes associated with cancer, including cell proliferation, apoptosis, cell migration, cell invasion, and angiogenesis. Thus, we aimed to evaluate the impact of serum ghrelin levels on survival in MIBC.MethodsIn this study, we reviewed the clinical and pathological records of 56 patients who were diagnosed with MIBC between November 2015 and November 2019 at Gifu and Hirosaki University Hospitals. We focused on 27 patients who had received chemotherapy and collected blood samples before and after chemotherapy. Blood samples were collected before chemotherapy and after completing two cycles of chemotherapy. Serum acyl (AG) and desacyl ghrelin (DG) were measured using AG and DG enzyme-linked immunosorbent assay kits (SCETI, Tokyo, Japan), respectively.ResultsThe 3-year overall and progression-free survival (PFS) rates were 82.9% and 68.3%, respectively. According to the AG level after chemotherapy, the 3-year PFS rates were 77.5% and 53.0% in patients with AG levels ≥1.34 and <1.34 pg/mL, respectively (P=0.038). With regard to DG levels after chemotherapy, the 3-year PFS rates were 90.9% and 43.3% in patients with DG levels <92.3 and ≥92.3 pg/mL, respectively (P=0.039). On multivariate analysis, serum AG levels were significantly associated with PFS.ConclusionsThis study suggested the usefulness of the ghrelin as a prognostic predictor of PFS in patients with MIBC.     

Ketamine inhibits inositol 1,4,5-trisphosphate production depending on the extracellular Ca2+ concentration in neonatal rat cardiomyocytes

We investigated the effect of ketamine on inositol 1,4,5-trisphosphate (IP3) formation in rat cardiomyocytes. After the addition of 1 micromol/L ketamine, IP3 production in the presence of 0.5, 1, 5, 10, and 30 mmol/L Ca2+ significantly decreased from 537.1+/-8.3, 590.7+/-12.9, 690.6+/-7.9, 754.8+/-12.5, and 823.7+/-15.2 pmol/mg protein to 467.0+/-8.3, 483.8+/-11.0, 512.6+/-21.3, 612.1+/-16.9, and 652.6+/-17.3 pmol/mg protein, respectively. When exposed to TMB-8 (a intracellular calcium inhibitor), IP3 production decreased significantly from 347.2+/-27.3 to 283.8+/-20.4 pmol/mg protein in the presence of 1 micromol/L ketamine, but A23187, which increases intracellular calcium, did not affect the inhibition of IP3 production by ketamine. These results demonstrate that ketamine decreases IP3 formation through inhibition of the calcium ion-sensing receptor and that IP3 formation reduced by ketamine is not affected by the alteration of intracellular calcium. IMPLICATIONS: Ketamine has a negative inotropic effect in isolated cardiomyocytes. The negative inotropic effect was associated with a decrease in inositol 1,4,5-trisphosphate production, and the inhibitory action was enhanced depending on the concentration of extracellular Ca2+.