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The synthetic immunomodulator cytotoxic T lymphocyte antigen 4-Ig (CTLA-4-Ig) initiates effects in human monocyte-derived dendritic cells (DC) that rely on immunosuppressive tryptophan catabolism. However, it is unable to induce suppressive properties in DC matured by CD40 engagement. Thus, CD40-driven events may physiologically set human DC free from restraint by regulatory cells expressing surface CTLA-4.  相似文献   
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Summary In the present paper, the effect of cryo-protective sugars on the survival rate of different strains of Lactic Acid Bacteria (LAB, Lactobacillus acidophilus, Lactobacillus delbrueckii subspbulgaricus, Streptococcus salivarius subsp.thermophilus), after freezing or freeze-drying procedures, was compared. The cells were incubated at 4 °C in 32% final concentration sugar solutions (trehalose, maltose, sucrose, glucose and lactose), and viability was evaluated by the enumeration of colony-forming units. All sugars tested showed a protective effect on cell viability as compared to isotonic solution, especially after freeze-drying procedures (log c.f.u./ml ranging between 1.16 and 2.08, P < 0.001). Furthermore, the resistance to different stress agents (lysozyme, pepsin, bile salts) was estimated. Trehalose was the most effective sugar in preserving bacterial viability [% (log c.f.u. trehalose/log c.f.u. isotonic solution) ranging between 124 and 175, P < 0.001] although each strain showed a different sensitivity. Finally, the protective effect of immobilization of LAB in Ca-alginate beads was compared to that exercised by trehalose. The immobilization induced a good survival rate but lower as compared to the trehalose effect, mainly after freeze-drying in the presence of the selective agents [% (log c.f.u. alginate/log c.f.u. trehalose ranging between 81.1 and 94.5, P < 0.0001]. The protective effect of trehalose was evident in particular for Lactobacillus delbrueckii subsp. bulgaricus in presence of lysozyme. Therefore, because of its chemical inertness and low cost, trehalose could be easily utilized as excellent bacterial preservative, both to improve the viability of starter cultures and to obtain probiotic formulations more resistant to a variety of stressful conditions.  相似文献   
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Coppola A  Hughes J  Esposito E  Schiavo L  Meli R  Diano S 《FEBS letters》2005,579(21):4654-4658
Fasting is characterized by disrupted thyroid feedback, with suppressed levels of thyroid hormones and paraventricular thyrotropin releasing hormone (TRH). We found that third ventricle administration of the deiodinase inhibitor, iopanoic acid, dose-dependently reduced deiodinase type II (DII) activity selectively in the hypothalamus. This suppression of DII by iopanoic acid during fasting prevented elevated DII activity and blunted the decline in hypothalamic TRH mRNA levels. Because fasting-induced elevation in hypothalamic DII activity is paralleled by increased hypothalamic T3 concentration, our study suggests that T3 formation by DII in the hypothalamus is the cause of disrupted thyroid feedback during fasting.  相似文献   
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Inhibition of the multifunctional Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) or depletion of sarcoplasmic reticulum (SR) Ca(2+) stores protects against apoptosis from excessive isoproterenol (Iso) stimulation in cultured ventricular myocytes, suggesting that CaMKII inhibition could be a novel approach to reducing cell death in conditions of increased adrenergic tone, such as myocardial infarction (MI), in vivo. We used mice with genetic myocardial CaMKII inhibition due to transgenic expression of a highly specific CaMKII inhibitory peptide (AC3-I) to test whether CaMKII was important for apoptosis in vivo. A second line of mice expressed a scrambled, inactive form of AC3-I (AC3-C). AC3-C and wild-type (WT) littermates were used as controls. AC3-I mice have reduced SR Ca(2+) content and are resistant to Iso- and MI-induced apoptosis compared with AC3-C and WT mice. Phospholamban (PLN) is a target for modulation of SR Ca(2+) content by CaMKII. PLN(-/-) mice have increased susceptibility to Iso-induced apoptosis. Verapamil pretreatment prevented Iso-induced apoptosis in PLN(-/-) mice, indicating the involvement of a Ca(2+)-dependent pathway. AC3-I and AC3-C mice were bred into a PLN(-/-) background. Loss of PLN increased and equalized SR Ca(2+) content in AC3-I, AC3-C, and WT mice and abolished the resistance to apoptosis in AC3-I mice after MI. There was a trend (P = 0.07) for increased Iso-induced apoptosis in AC3-I mice lacking PLN compared with AC3-I mice with PLN. These findings indicate CaMKII is proapoptotic in vivo and suggest that regulation of SR Ca(2+) content by PLN contributes to the antiapoptotic mechanism of CaMKII inhibition.  相似文献   
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The present study provides specific cytogenetic information on prometaphase chromosomes of the alpaca (Lama pacos, fam. Camelidae, 2n = 74) that forms a basis for future work on karyotype standardization and gene mapping of the species, as well as for comparative studies and future genetic improvement programs within the family Camelidae. Based on the centromeric index (CI) measurements, alpaca chromosomes have been classified into four groups: group A, subtelocentrics, from pair 1 to 10; group B, telocentrics, from pair 11 to 20; group C, submetacentrics, from pair 21 to 29; group D, metacentrics, from pair 30 to 36 plus sex chromosomes. For each chromosome pair, the following data are provided: relative chromosome length, centromeric index, conventional Giemsa staining, sequential QFQ/C-banding, GTG- and RBG-banding patterns with corresponding ideograms, RBA-banding and sequential RBA/silver staining for NOR localization. The overall number of RBG-bands revealed was 391. Nucleolus organizer-bearing chromosomes were identified as pairs 6, 28, 31, 32, 33 and 34. Comparative ZOO-FISH analysis with camel (Camelus dromedarius) X and Y painting probes was also carried out to validate X-Y chromosome identification of alpaca and to confirm close homologies between the sex chromosomes of these two species.  相似文献   
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We have recently shown that unilateral naris occlusion (UNO) causes an increase in olfactory marker protein (OMP) immunoreactivity (IR) in mouse olfactory sensory neurons (OSN) from the occluded side of the nasal cavity and a decrease in OMP-IR on the non-occluded side, relative to controls. Given OMP's demonstrated role in olfactory modulation, these OMP-IR changes have been interpreted as a compensatory response by OSNs to odor deprivation on the occluded side and to supernormal exposure to odor on the non-occluded side of the nasal cavity. In the current study, we examined the developmental timing and the regional distribution of this process throughout the nasal cavity using immunocytochemistry. Results demonstrate that OMP-IR diverges in OSNs from the occluded side relative to the non-occluded side of the nasal cavity within eleven days after UNO, with statistically significant differences measurable after 17 days (n=16). We also measured relative levels of the Type 4 phosphodiesterase (PDE4A), another potential olfactory modulator, in nasal cavity tissue from UNO (n=8) and untreated mice (n=9) using western blots and immunocytochemistry. Like OMP, PDE4A-IR increased on the occluded side of the nasal cavity after UNO. Finally, we used immunocytochemistry to assess relative levels of olfactory-specific adenylyl cyclase (ACIII, n=4) and G-protein (Golf, n=2) in OSNs from the occluded and non-occluded sides of the nasal cavity of UNO mice. Following UNO, ACIII but not Golf -IR levels diverged comparing the occluded to the non-occluded sides of the nasal cavity. Taken together, our findings provide support for the previously unknown phenomenon of compensatory responses by OSNs to odor environment.  相似文献   
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Several studies demonstrate links between environmental stress and index of reduced health, including risk factors for cardiovascular disease, reduced immune function and cancer risks. We investigated the hypothesis that pollution, as an environmental stress, impacts health by modulating the rate of cellular aging in healthy pregnant women. Our research looked at the effects that illegal waste sites have on the localized population of pregnant women in Campania, Italy. As is often the case in illegal dumping, the effects on the population are often seen well before knowing what specific agents in the soil and water are responsible. Here we provide evidence that the pollution in this region is significantly associated with higher oxidative stress, shorter telomere length and lower telomerase activity, which are known determinants of cell senescence and aging-related meiotic dysfunction in women, in peripheral blood mononuclear cells from healthy pregnant women, subjected to therapeutic abortion in the second trimester of pregnancy. These findings may have implications for understanding how, at the cellular level, environmental stress may promote earlier onset of age-related diseases.  相似文献   
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