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The correlation between microbial community succession and volatile flavor substance changes in the fermentation of new pickle fermentation broth was revealed in this study via high-throughput sequencing and gas chromatography-mass spectrometry (GC-MS). Microbiological analysis demonstrated that Lactobacillus(relative abundance ≥93.98%) was the dominant bacterial genus in the broth, whereas Enterobacterwas richest only in the first sampling. E-nose and GC-MS inspections revealed that the types and contents of volatile flavor compounds increased continuously with fermentation, rising from 27 volatile flavor compounds in the first sampling to a maximum of 62 species, with the content increasing from 8.686 μg/mL to 106.083 μg/mL. Olefins and alcohols had the highest proportions throughout the fermentation process. The Spearman correlation coefficient revealed that 77 volatile flavor compounds and 22 bacterial genera had medium-high correlations (|ρ| >0.6). Lactobacillus(Gen1), the most dominant genus, was significantly positively correlated with 21 volatile compounds (ρ > 0.6), including myrcene (Ole7), terpinene (Ole12) and ocimene (Ole1), but negatively associated with 13 volatile compounds (ρ < -0.6), including 5-methyl-4-nonene (Ole5l), anisole (Ole26) and 2-octen-4-one (Ket6). Thus, this study may provide a theoretical basis to improve the flavour and overall quality of the new pickle fermentation broth.

Phosphine oxide-Sc(OTf)3catalyzed regio- and enantioselective bromoaminocyclization of tri-substituted allyl N-tosylcarbamates is described. A wide variety of optically active tertiary 5-bromo-1,3-oxazinan-2-ones can be obtained with high regio-and enantioselectivity.

Luteal-phase insufficiency is one of the major causes of female infertility, but the molecular mechanisms are still largely unknown. Here we found that disruption of Lgr4/Gpr48, the newly identified receptor for R-spondins, greatly reduced female fertility in mice. The expression of Lgr4was induced specifically in granulosa-lutein cells during luteinization. In Lgr4-deficient female mice, the estrous cycle was prolonged and serum progesterone levels were dramatically downregulated. In Lgr4−/−corpora lutea, the expression of key enzymes for steroidogenesis as well as common luteal marker genes was significantly decreased. Additionally, the activity of epidermal growth factor receptor (EGFR)-ERK signaling was attenuated in Lgr4−/−granulosa-lutein cells. We found that the maturation of Lgr4−/−cells was impaired in cultured primary granulosa cells, but the defect was partially rescued by reactivation of EGFR signaling by heparin-binding EGF-like growth factor treatment. We found that the expression of wingless-type MMTV integration site family (WNT)/catenin (cadherin associated protein), beta 1 (CTNNB1) downstream targets, including matrix metalloproteinase 9, which is a critical matrix metalloproteinase for activation of EGF-like factors, was significantly downregulated in Lgr4−/−ovaries. Matrix metalloproteinase 9 inhibitor treatment attenuated human chorionic gonadotropin- but not heparin-binding EGF-like growth factor-induced ERK activation and luteinization in primary granulosa cells. Together, we report that Lgr4modulates WNT-mediated EGFR-ERK signaling to facilitate corpus luteum maturation and ovarian steroidogenesis to maintain female reproduction.

Mast cells play critical roles in allergic disorders and asthma. The importance of tuberous sclerosis complex 1/2-mammalian target of rapamycin (TSC1/2-mTOR) signaling in mast cells is unknown. Here, we report that TSC1 is a critical regulator for mTOR signaling in mast cells downstream of FcεRI and c-Kit, and differentially controls mast cell degranulation and cytokine production. TSC1-deficiency results in impaired mast cell degranulation, but enhanced cytokine production in vitro and in vivo after FcεRI engagement. Furthermore, TSC1 is critical for mast cell survival through multiple pathways of apoptosis including the down-regulation of p53, miR-34a, reactive oxygen species, and the up-regulation of Bcl-2. Together, these findings reveal that TSC1 is a critical regulator of mast cell activation and survival, suggesting the manipulation of the TSC1/2-mTOR pathway as a therapeutic strategy for mast cell-mediated diseases.

Mast cells play critical roles in allergic disorders and asthma. The importance of tuberous sclerosis complex 1/2-mammalian target of rapamycin (TSC1/2-mTOR) signaling in mast cells is unknown. Here, we report that TSC1 is a critical regulator for mTOR signaling in mast cells downstream of FcεRI and c-Kit, and differentially controls mast cell degranulation and cytokine production. TSC1-deficiency results in impaired mast cell degranulation, but enhanced cytokine production in vitro and in vivo after FcεRI engagement. Furthermore, TSC1 is critical for mast cell survival through multiple pathways of apoptosis including the down-regulation of p53, miR-34a, reactive oxygen species, and the up-regulation of Bcl-2. Together, these findings reveal that TSC1 is a critical regulator of mast cell activation and survival, suggesting the manipulation of the TSC1/2-mTOR pathway as a therapeutic strategy for mast cell-mediated diseases.

It has been universally believed that spindle assembly checkpoint (SAC) proteins which include the kinetochore proteins are involved in monitoring the faithful segregation of sister chromatids during cell division and hence defects in these proteins result in anueploidy. Furthermore, there are multiple sources of experimental data to suggest that a defect in p53 could also promote genomic instability leading to anueploidy. Despite these observations, a molecular basis for the prevention of aneuploidy to maintain genomic integrity upon activation of SAC has largely remained elusive. In this report, we demonstrate a novel mechanism for the maintenance of a balance between cell survival and apoptosis upon activation of SAC. We found that depletion of the outer kinetochore protein hBub1 upon activation of SAC primarily triggers early cell death mediated by p53. This phenomenon is further supported by the up-regulation of p53 down-stream pro-apoptotic genes, BAX and PUMA as well as a corresponding increase in the cleavage products of PARP and caspase 3, markers of apoptosis upon depletion of hBub1 in SAC activated cells. On the other hand, as expected, concomitant loss of both hBub1 and p53 resulted in disabling of the p53 mediated cell death pathway leading to the accumulation of cells with aneuploidy/polyploidy.Commentary also to:hBub1 negatively regulates p53 mediated early cell death upon mitotic checkpoint activationFangming Gao, Jose F Ponte, Panagiotis Papageorgis, Mary Levy, Sait Ozturk, Arthur W. Lambert, Arunthathi Thiagalingam, Hamid Mostafavi Abdolmaleky, Beth A Sullivan and Sam Thiagalingam

The IL-1 receptor-associated kinase 1 (IRAK-1) and IRAK-M are key signaling molecules in cellular responses to endotoxin initiated through the Toll-like receptors (TLRs). The aim of this study was to evaluate the effect of age on the modulation of TLRs and IRAK-1 and IRAK-M in peripheral blood mononuclear cells (PBMCs) exposed in vitroto endotoxin under conditions that could induce endotoxin tolerance. Peripheral blood mononuclear cells obtained from young (4- to 6-month-old) and aged (24- to 26-month-old) Brown Norway rats were treated with high-dose LPS, with or without priming with low-dose LPS. In comparison with younger rats, the intensity of TLR-4 expression was persistently high in monocytes from aged rats after stimulation with LPS and was not decreased by priming with low-dose LPS (P< 0.05). Messenger RNA (mRNA) for TLR-4 in PBMCs from aged rats did not show any decrease after priming with low-dose LPS as seen in PBMCs from young rats at 24 h (P= 0.01) after restimulation. In PBMCs from young rats, but not aged rats, preconditioning with low-dose LPS and subsequent stimulation with high-dose LPS resulted in markedly decreased IRAK-1 protein (P= 0.02) and decreased mRNA for IRAK-1 (P< 0.05). In contrast, PBMCs from aged rats treated in this manner continued to express measurable levels of IRAK-1 protein. Preconditioning with low-dose LPS caused an increase in both IRAK-M protein and mRNA (P= 0.05) after stimulation with high-dose LPS only in cells from young rats. These phenotypic characteristics of PBMCs from aged rats can interfere with their ability to develop tolerance to endotoxin.

γ-catenin (plakoglobin) exists in cells either as a component of adherens junctions, along with β-catenin and α-catenin, or in association with desmoplakin in desmosomes, which are in turn coupled to the cytoskeleton linking to the plasma membrane. Although γ-catenin overexpression is observed in many cancers, the molecular basis of its contribution to tumor progression remains unclear. In this study, we examined γ-catenin overexpression-mediated effects leading to altered regulation of effector genes such as PTTG and c-Myc, as well as differential activation of signaling pathways. We found that overexpression of γ-catenin caused: (1) a reduction in E-cadherin and corresponding increase in vimentin levels concomitant with increased cell mobility and migration; (2) enhancement in the levels of phosphorylated Akt and Erk in the presence of EGF; and (3) an increase in PTTG and c-Myc protein levels, which are likely to accelerate chromosomal instability and uncontrolled proliferation, respectively, in the affected cells. These effects resulting from overexpression of γ-catenin were further validated in converse experiments with the aid of siRNA knockdown of the endogenous γ-catenin gene. In conclusion, our studies provide a molecular basis for the promotion of genomic instability and the oncogenic effects due to overexpression of γ-catenin in human cancer.