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We compute the one-loop divergences in a higher-derivative theory of gravity including Ricci tensor squared and Ricci scalar squared terms, in addition to the Hilbert and cosmological terms, on an (generally off-shell) Einstein background. We work with a two-parameter family of parametrizations of the graviton field, and a two-parameter family of gauges. We find that there are some choices of gauge or parametrization that reduce the dependence on the remaining parameters. The results are invariant under a recently discovered "duality" that involves the replacement of the densitized metric by a densitized inverse metric as the fundamental quantum variable. [ABSTRACT FROM AUTHOR]

Background: Although enteral nutrition (EN) therapy for Crohn's disease has been confirmed to be as effective as steroid therapy, the precise mechanism responsible for the effects of EN remains unclear, although some of the therapeutic effects of EN are believed to be due to a low dietary fat content. In order to elucidate the influence of fat in EN, it is important to investigate not only the quantity of fat, but also the source of the fat.Methods: We compared two enteral nutritional formulae: Elental (Ajinomoto) (elemental diet; ED), which contains only 1.5% fat, provided as long-chain triglycerides (LCT), versus Twinline (Snow Brand Milk Products) (TL), which contains a high percentage of fat (20.4%), provided mainly as medium-chain triglycerides (MCT). These formulae were tested on rat enteritis and rat colitis induced by trinitrobenzene sulfonic acid (TNBS).Results: Both ED and TL reduced the manifestations of enteritis. TL had a stronger anti-inflammatory effect than ED for colitis. TL also had nutritional advantages as compared with ED, as shown by the total serum protein in the TL group being significantly higher than that in the ED group.Conclusion: The results indicate that intraluminal MCT is suitable as a fat energy source during intestinal inflammation in rats. We suggest that Twinline may be more useful to improve nutritional status and to reduce the mucosal inflammation in rat colitis, but that Twinline is equal in effect to Elental for rat enteritis. [ABSTRACT FROM AUTHOR]

Focuses on the existence of soluble CD44 in human follicular fluid and its prognostic value in in vitro fertilization programs. Association with human chorionic gonadotropin; Univariate linear regression analysis; Impact of mean follicular levels of soluble CD44 on oocyte fertilization and morphological embryo quality.

The amounts of cell-nuclear DNA (cl-DNA), mitochondrial DNA (mt-DNA) and chloroplast DNA (cp-DNA) in Cyanidioschyzon merolae were estimated by using a video-intensified microscope (VIM) system. C. merolae had the smallest amount of cell-nuclear DNA among eukaryotes. The results show that a cell-nucleus, a mitochondrion and a chloroplast contain an average 8.0×10kbp, 1.6×10kbp, and 5.0×10kbp, respectively. To confirm these results, cl-DNA, mt-DNA, and cp-DNA were isolated from cells by density centrifugation on Hoechst 33258/CsCl after density centrifugation on ethidium bromide/CsCl. The amounts of cl-DNA, mt-DNA, and cp-DNA obtained from the bands supported the data shown by the VIM-system. The cytochemical and biochemical characteristics were compared with those of Cyanidium caldarium RK-1 and C. caldarium Forma A. The ρ values of cl-DNA and cp-DNA of C. merolae were about 1.716 and 1.709, respectively. The order in density was different from that of C. caldarium Forma A but very similar to that of C. caldarium RK-1. However, the restriction patterns of cp-DNA in C. merolae differed from those of C. caldarium RK-1. [ABSTRACT FROM AUTHOR]

T-cell responses to pathogenic free-living amoebae, Acanthamoeba sp., were analyzed in healthy Japanese individuals. Of 20 healthy subjects, 10 (50%) showed significant proliferative responses of peripheral blood mononuclear cells to the soluble amoebic antigens in vitro. The antigens used were not mitogenic, and no evidence of amoebic superantigens was available. We established human T-cell clones reactive to Acanthamoeba, all of which were CD3- and CD4-positive, CD8-negative, and TCR-αβ-positive. We isolated two strains of Acanthamoeba from two patients, one from a patient with meningoencephalitis (CSF strain) and the other from a patient with keratitis (K strain). Of 13 clones, 11 were reactive to the K-strain as well as to the CSF-strain antigen under human leukocyte antigen (HLA)-DR restriction, whereas the other two were specific for the K-strain antigen. All but one clone tested showed TH1-equivalent functions because these cells produced interferon (IFN)-γ in response to the amoebic antigen but produced no detectable level of interleukin 4 (IL-4). These results suggest that immunocompetent hosts might have acquired protective immunity mediated by Acanthamoeba-specific T-cells during natural sensitization. [ABSTRACT FROM AUTHOR]

Serum-mediated regulation of T-cell responses specific for soluble egg antigen (SEA) of Schistosoma japonicum was tested in human hosts. When we added autologous serum to SEA-specific human T-cell lines (CD3+, 4+, 8−), we observed suppression of T-cell proliferation, and this suppressive activity was detected in the immunoglobulin-G2 (IgG) subclass. Suppression was dose-dependent and antigen-specific. T-cell proliferation induced by only one SEA fraction of >18 kDa was modulated in the presence of 100 μg/ml autologous as well as allogeneic infected IgG. This SEA fractiondriven proliferation was also regulated by suppressor T-cells through distinct suppressive mechanisms. Our results suggest that T-cell responses to a particular component(s) of SEA are strictly regulated through both cellular and humoral mechanisms in human chronic S. japonicum infection. [ABSTRACT FROM AUTHOR]

Changes in alkaline phosphatase (ALPase) activity in rabbit articular cartilage induced by joint contracture were studied by light and electron microscopy. The knee joint was plaster-immobilized for 3-9 weeks in the flexion position. Three different age groups of rabbits were examined, at the age of 1 month (young), 1 year (adult), and over 2.5 years (old). ALPase activity was detected in the cartilage taken from the distal end of the femur, employing the lead citrate method. Positive activity was primarily localized in the plasma membrane of the chondrocytes and also in the pericellular matrix vesicles. Before immobilization the positive cells were distributed exclusively in the deep zone of the cartilage, whereas after immobilization activity was present in cells both in the middle and deep zones. This phenomenon was most evident in the old group. [ABSTRACT FROM AUTHOR]

A procedure is suggested for the preparation of porous silicon-based ferroelectric nanostructures. It is demonstrated that the method of chemical deposition from solutions provides for the penetration of the initial components of the solution into the matrix pores, and subsequent annealing leads to the crystallization of the ferroelectric phase. The diagnostics of the ferroelectric properties is performed using the method of generation of second optical harmonic. The spectral characteristics of the prepared ferroelectric nanostructures are investigated. [ABSTRACT FROM AUTHOR]

Oxygen is critical for all metazoan organisms on the earth and impacts various biological processes in physiological and pathological conditions. While oxygen-sensing systems inducing acute hypoxic responses, including the hypoxia-inducible factor pathway, have been identified, those operating in prolonged hypoxia remain to be elucidated. Here we show that pyridoxine 5'-phosphate oxidase (PNPO), which catalyses bioactivation of vitamin B6, serves as an oxygen sensor and regulates lysosomal activity in macrophages. Decreased PNPO activity under prolonged hypoxia reduced an active form of vitamin B6, pyridoxal 5'-phosphate (PLP), and inhibited lysosomal acidification, which in macrophages led to iron dysregulation, TET2 protein loss and delayed resolution of the inflammatory response. Among PLP-dependent metabolism, supersulfide synthesis was suppressed in prolonged hypoxia, resulting in the lysosomal inhibition and consequent proinflammatory phenotypes of macrophages. The PNPO-PLP axis creates a distinct layer of oxygen sensing that gradually shuts down PLP-dependent metabolism in response to prolonged oxygen deprivation., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)