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Functional telomeres protect chromosome ends and play important roles in stem cell maintenance and differentiation. Short telomeres negatively impact germ cell development and can contribute to age-associated infertility. Moreover, telomere syndrome resulting from mutations of telomerase or telomere-associated genes exhibits short telomeres and reduced fertility. It remains elusive whether and how telomere lengths affect germ cell specification. We report that functional telomere is required for the coordinated germ cell and somatic cell fate decisions. Using telomerase gene Terc deficient mice as a model, we show that short telomeres restrain germ cell specification of epiblast cells but promote differentiation towards somatic lineage. Short telomeres increase chromatin accessibility to elevate TGFβ and MAPK/ERK signaling for somatic cell differentiation. Notably, elevated Fst expression in TGFβ pathway represses the BMP4-pSmad signaling pathway, thus reducing germ cell formation. Re-elongation of telomeres by targeted knock-in of Terc restores normal chromatin accessibility to suppress TGFβ and MAPK signaling, thereby facilitating germ cell formation. Taken together, our data reveal that functional telomeres are required for germ cell specification by repressing TGFβ and MAPK signaling.

Vegetative and reproductive phase change and phenology are economically and ecologically important traits. Trees typically require several years of growth before flowering and, once mature, seasonal control of the transition to flowering and flower development is necessary to maintain vegetative meristems and for reproductive success. Members of two related gene subfamilies, FLOWERING LOCUST (FT) and TERMINAL FLOWER1 (TFL1)/CENTRORADIALIS (CEN)/BROTHER OF FT AND TFL1 (BFT), have antagonistic roles in flowering in diverse species and roles in vegetative phenology in trees, but many details of their functions in trees have yet to be resolved. Here, we used CRISPR/Cas9 to generate single and double mutants involving the five Populus FT and TFL1/CEN/BFT genes. The ft1 mutants exhibited wild-type-like phenotypes in long days and short days, but after chilling, to release dormancy, they showed delayed bud flush and GA3 could compensate for the ft1 mutation. After rooting and generating some phytomers in tissue culture, both cen1 and cen1ft1 mutants produced terminal as well as axillary flowers, indicating that the cen1 flowering phenotype is independent of FT1. The CEN1 showed distinct circannual expression patterns in vegetative and reproductive tissues and comparison with the expression patterns of FT1 and FT2 suggests that the relative levels of CEN1 compared with FT1 and FT2 regulate multiple phases of vegetative and reproductive seasonal development.

Vegetative and reproductive phase change and phenology are economically and ecologically important traits. Trees typically require several years of growth before flowering and once mature, seasonal control of the transition to flowering and flower development is necessary to maintain vegetative meristems and for reproductive success. Members of two related gene subfamilies, FLOWERING LOCUST (FT) and TERMINAL FLOWER1 (TFL1)/CENTRORADIALIS (CEN)/BROTHER OF FT AND TFL1 (BFT), have antagonistic roles in flowering in diverse species and roles in vegetative phenology in trees, but many details of their functions in trees have yet to be resolved. Here, we used CRISPR/Cas9 to generate single and double mutants involving the five Populus FT and TFL1/CEN/BFT genes. ft1 mutants exhibited wild-type-like phenotypes in long days and short days, but after chilling to release dormancy showed delayed bud flush and GA3 could compensate for the ft1 mutation. After rooting and generating some phytomers in tissue culture, both cen1 and cen1ft1 mutants produced terminal as well as axillary flowers, indicating that the cen1 flowering phenotype is independent of FT1. Some axillary meristems initially generated phytomers and in potted plants, the timing of flowering in these shoots correlated with upregulation of FT2 in maturing leaves, suggesting that, in long days, CEN1 antagonizes FT2 promotion of flowering but enables FT2 promotion of shoot growth by maintaining indeterminacy of the shoot apical meristem. CEN1 showed distinct circannual expression patterns in vegetative and reproductive tissues and comparison with the expression patterns of FT1 and FT2 suggest that the relative levels of CEN1 compared to FT1 and FT2 regulate multiple phases of vegetative and reproductive seasonal development.

Both the evolution of tree taxa and whole-genome duplication (WGD) have occurred many times during angiosperm evolution. Transcription factors are preferentially retained following WGD suggesting that functional divergence of duplicates could contribute to traits distinctive to the tree growth habit. We used gain- and loss-of-function transgenics, photoperiod treatments, and circannual expression studies in adult trees to study the diversification of three

In the original publication the labelling of Figure 1D, Y-axis is incorrectly published. The correct labeling should be read as Fragilis+/SSEA1+ and the correct figure is provided in this correction.

The aim of the present study was to evaluate the safety, pharmacokinetic (PK) and pharmacodynamic (PD) properties of remimazolam besylate following single ascending dose (SAD) and continuous infusion in healthy Chinese volunteers. This was a randomized phase I study conducted in two parts. Part I was a double-blind, placebo- and midazolam-controlled, SAD study among healthy Chinese participants with a remimazolam dose of 0.025–0.4 mg/kg. Part II was an open-label, midazolam-controlled, continuous infusion study. Bispectral index (BIS) monitoring and Modified Observers Assessment of Alertness and Sedation (MOAA/S) score assessment were used to assess the PD properties. The half-life range of remimazolam was from 34.1 ± 8.1 to 59.8 ± 20.5 min in the SAD study. The sedation function was initially observed at the dose of 0.05 mg/kg remimazolam. Doses of ≥ 0.075 mg/kg exerted a peak sedation effect within 1–2 min after injection, resulting in a deeper and more rapid sedation. In the 2 h continuous infusion, remimazolam showed a deeper sedation and more rapid recovery than midazolam. For general anesthesia, an induction dosage of 0.2 mg/kg/min and a maintenance dosage of 1 mg/kg/h can achieve a satisfactory efficacy effect. Remimazolam was safe and well tolerated in healthy Chinese participants. Based on the phase I clinical study, we suggest that remimazolam besylate demonstrates greater sedation and quicker recovery from sedation than midazolam.

Parthenogenetic embryos, created by activation and diploidization of oocytes, arrest at mid-gestation for defective paternal imprints, which impair placental development. Also, viable offspring has not been obtained without genetic manipulation from parthenogenetic embryonic stem cells (pESCs) derived from parthenogenetic embryos, presumably attributable to their aberrant imprinting. We show that an unlimited number of oocytes can be derived from pESCs and produce healthy offspring. Moreover, normal expression of imprinted genes is found in the germ cells and the mice. pESCs exhibited imprinting consistent with exclusively maternal lineage, and higher X-chromosome activation compared to female ESCs derived from the same mouse genetic background. pESCs differentiated into primordial germ cell-like cells (PGCLCs) and formed oocytes following in vivo transplantation into kidney capsule that produced fertile pups and reconstituted ovarian endocrine function. The transcriptome and methylation of imprinted and X-linked genes in pESC-PGCLCs closely resembled those of in vivo produced PGCs, consistent with efficient reprogramming of methylation and genomic imprinting. These results demonstrate that amplification of germ cells through parthenogenesis faithfully maintains maternal imprinting, offering a promising route for deriving functional oocytes and having potential in rebuilding ovarian endocrine function. Supplementary Information The online version contains supplementary material available at 10.1007/s13238-021-00865-4.

OBJECTIVE: To investigate the psychological status and sleep quality of nursing interns in collective isolation during the outbreak of coronavirus disease 2019 (COVID-19) and provide evidence for adequate interventions. METHODS: We surveyed a total of 95 nursing interns who were isolated collectively in a general teaching hospital in Guangzhou using a self-designed questionnaire, which consisted of a basic information form, self-rating anxiety scale (SAS), self-rating depression scale (SDS) and Pittsburgh Sleep Quality Index (PSQI). Descriptive analysis, single factor analysis and correlation analysis were used to analyze the current status of the interns' psychology and sleep quality, the potential factors affecting their psychology and sleep quality, and the correlation between their psychological status and sleep quality. RESULTS: The surveyed interns had SAS, SDS and PSQI score of 37.79±6.59, 43.98±9.74 and 5.20±3.14, respectively, which were significant higher than the national norms in China (P < 0.05). Correlation analysis indicated that both anxiety and depression were positively correlated with the sleep quality score (r=0.508 and 0.546, respectively). Univariate analysis showed that the major factors affecting the psychological status and sleep quality of the interns during collective isolation included recent contact with persons from the affected area before isolation and the onset of fever during the isolation. CONCLUSION: These interns showed relatively high levels of anxiety and depression during the collective isolation to affect their sleep quality, and interventions should be timely administered to improve their mental health and sleep quality.

Sarsia tubulosa (M. Sars, 1835) belongs to the family Corynidae, and is mainly distributed in coastal boreal and arctic waters. During regular zooplankton sampling in a coastal artificial lake (Lake Fenghuang) near the northern Yellow Sea (36°55′N, 122°24′E) in May 2015, we found high densities of Sarsia sp. in the zooplankton samples. The mean density of the medusae was 50 ± 40 individuals m−3 (mean ± SD). These specimens were characterized by a long tube-like manubrium and were consistent with previous descriptions of S. tubulosa. Furthermore, a molecular phylogenetic analysis of the mitochondrial cytochrome c oxidase I subunit gene fragments revealed that these individuals clustered with S. tubulosa. Therefore, based on both morphological and molecular data, these specimens were identified as S. tubulosa. This report represents the first formal record of S. tubulosa in Chinese coastal waters, which extended its known geographical distribution.

Summary Chemically induced pluripotent stem cells (CiPSCs) may provide an alternative and attractive source for stem cell-based therapy. Sufficient telomere lengths are critical for unlimited self-renewal and genomic stability of pluripotent stem cells. Dynamics and mechanisms of telomere reprogramming of CiPSCs remain elusive. We show that CiPSCs acquire telomere lengthening with increasing passages after clonal formation. Both telomerase activity and recombination-based mechanisms are involved in the telomere elongation. Telomere lengths strongly indicate the degree of reprogramming, pluripotency, and differentiation capacity of CiPSCs. Nevertheless, telomere damage and shortening occur at a late stage of lengthy induction, limiting CiPSC formation. We find that histone crotonylation induced by crotonic acid can activate two-cell genes, including Zscan4; maintain telomeres; and promote CiPSC generation. Crotonylation decreases the abundance of heterochromatic H3K9me3 and HP1α at subtelomeres and Zscan4 loci. Taken together, telomere rejuvenation links to reprogramming and pluripotency of CiPSCs. Crotonylation facilitates telomere maintenance and enhances chemically induced reprogramming to pluripotency., Graphical Abstract, Highlights • CiPSCs acquire telomere elongation after clonal formation with increasing passages • Both telomerase and recombination mechanisms are involved in the telomere elongation • Telomere damage and shortening can occur during late stage of lengthy induction • Crotonylation activates Zscan4 and promotes telomere elongation and CiPSC induction, In this article, Liu and colleagues show that telomere rejuvenation links to reprogramming and pluripotency of CiPSCs. Moreover, crotonylation induced by crotonic acid facilitates telomere maintenance and enhances chemically induced reprogramming to pluripotency.

A tree shoot includes multiple developmental gradients that reflect the relationships of the shoot apical meristem, the cambial meristem and the tissues and organs they produce. The adaptation of trees to temperate and boreal climates depends on the ability of these two meristems to appropriately respond to environmental signals that are markers of seasonal changes. The aim of this review is to present a more holistic view of the tree shoot, including the developmental changes associated with seasonally regulated growth transitions. We consider the role of long-distance communication in coordinating leaf development, the transition to secondary growth and meristem activity. Using Populus as the model, we discuss the roles of signalling mediated by hormones, sugar and FLOWERING LOCUS T2 (FT2) in coordinating tree shoot developmental processes.

Lysophosphatidic acid (LPA) is a bioactive phospholipid that is present in all tissues examined to date. LPA signals extracellularly via cognate G protein-coupled receptors to mediate cellular processes such as survival, proliferation, differentiation, migration, adhesion and morphology. These LPA-influenced processes impact many aspects of organismal development. In particular, LPA signalling has been shown to affect fertility and reproduction, formation of the nervous system, and development of the vasculature. Here and in the accompanying poster, we review the developmentally related features of LPA signalling.

Ovarian aging occurs earlier than somatic aging. We tested the hypothesis that ovarian functions could be artificially reconstructed by transplantation of primordial germ cells (PGCs). We compared various methods for transplantation of PGCs aggregated with gonadal somatic cells and showed that reconstituted ovaries exhibited folliculogenesis after transplantation of PGCs-aggregates into either kidney capsule or ovarian bursa. Neo-oogenesis occurred early after transplantation, as evidenced by the presence of prophase I meiocytes displaying homologous pairing. Moreover, endocrine function was recovered in ovariectomized recipients, including elevated levels of AMH and estradiol. Interestingly, folliculogenesis in the reconstituted ovaries failed to sustain past four weeks. Regardless of transplantation method, follicles diminished after 45 days, accompanied by increased apoptosis, and were undetectable after two months. Meanwhile, no replicative PGCs or prophase I meiocytes could be found. Together, transplantation of PGCs can effectively reconstitute ovarian functions but for limited time. These data suggest that PGCs do not undergo self-renewal but rapidly enter meiosis following transplantation. Global activation of primordial follicles in artificial ovaries can result in further rapid loss of germ cells. Methods for maintaining self-renewal and expansion in vivo of PGCs and controlling follicle activation will be essential for continuing maintenance of the functional reconstructed ovaries.

Dietary fiber supplements are used to manage fecal incontinence (FI), but little is known about the fiber type to recommend or the level of effectiveness of such supplements, which appears related to the fermentability of the fiber. The aim of this single-blind, randomized controlled trial was to compare the effects of three dietary fiber supplements (carboxymethylcellulose [CMC], gum arabic [GA], or psyllium) with differing levels of fermentability to a placebo in community-living individuals incontinent of loose/liquid feces. The primary outcome was FI frequency; secondary outcomes included FI amount and consistency, supplement intolerance, and quality of life (QoL). Possible mechanisms underlying supplement effects were also examined. After a 14-day baseline, 189 subjects consumed a placebo or 16 g total fiber/day of one of the fiber supplements for 32 days. FI frequency significantly decreased after psyllium supplementation versus placebo, in both intent-to-treat and per-protocol mixed model analyses. CMC increased FI frequency. In intent-to-treat analysis, the number of FI episodes/week after supplementation was estimated to be 5.5 for Placebo, 2.5 for Psyllium, 4.3 for GA, and 6.2 for CMC. Only psyllium consumption resulted in a gel in feces. Supplement intolerance was low. QoL scores did not differ among groups. Patients with FI may experience a reduction in FI frequency after psyllium supplementation, and decreased FI frequency has been shown to be an important personal goal of treatment for patients with FI. Formation of a gel in feces appears to be a mechanism by which residual psyllium improved FI.

Summary: The generation of genomically stable and functional oocytes has great potential for preserving fertility and restoring ovarian function. It remains elusive whether functional oocytes can be generated from adult female somatic cells through reprogramming to germline-competent pluripotent stem cells (gPSCs) by chemical treatment alone. Here, we show that somatic granulosa cells isolated from adult mouse ovaries can be robustly induced to generate gPSCs by a purely chemical approach, with additional Rock inhibition and critical reprogramming facilitated by crotonic sodium or acid. These gPSCs acquired high germline competency and could consistently be directed to differentiate into primordial-germ-cell-like cells and form functional oocytes that produce fertile mice. Moreover, gPSCs promoted by crotonylation and the derived germ cells exhibited longer telomeres and high genomic stability like PGCs in vivo, providing additional evidence supporting the safety and effectiveness of chemical induction, which is particularly important for germ cells in genetic inheritance. : Tian et al. report the successful generation of functional oocytes with genomic stability that produce fertile pups from adult-granulosa-cell-derived gPSCs through chemical reprogramming, which exhibits great potential for preserving fertility and restoring ovarian function. Keywords: chemical reprogramming, pluripotent stem cell, oocyte, granulosa cell

Telomere shortening is associated with aging and age-associated diseases. Additionally, telomere dysfunction resulting from telomerase gene mutation can lead to premature aging, such as apparent skin atrophy and hair loss. However, the molecular signaling linking telomere dysfunction to skin atrophy remains elusive. Here we show that dysfunctional telomere disrupts BMP/pSmad/P63 signaling, impairing epidermal stem cell specification and differentiation of skin and hair follicles. We find that telomere shortening mediated by Terc loss up-regulates Follistatin (Fst), inhibiting pSmad signaling and down-regulating P63 and epidermal keratins in an ESC differentiation model as well as in adult development of telomere-shortened mice. Mechanistically, short telomeres disrupt PRC2/H3K27me3-mediated repression of Fst. Our findings reveal that skin atrophy due to telomere dysfunction is caused by a previously unappreciated link with Fst and BMP signaling that could be explored in the development of therapies., Author summary Patients with mutations in the telomerase component (eg, Dyskerin, TERT, TERC) are frequently accompanied by symptoms of abnormal epidermis, such as hyperpigmentation, premature skin degradation, hair follicle shedding, skin atrophy, and dry skin. Mice with mutations in telomere-associated proteins or telomerase genes also show similar phenotypes, associated with telomere shortening. However, the underlying molecular signaling and mechanisms remain elusive. Here, we show that the differentiation of epidermis is disrupted resulting from short telomeres. Epidermal differentiation abnormalities can be rescued as the telomere length is extended. Furthermore, we uncover that Fst-BMP-Smad pathway is implicated in regulation of epidermal differentiation by telomeres length.

The formation of endoscopic biofilm reduces the results of cleaning and disinfection and may increase nosocomial infection. This study aims to evaluate the effects of various detergents and different contact time on the removal of biofilm on flexible endoscopes based on an artificial biofilm model.Endoscopic biofilm model was established and treated with various detergents (detergent 1, Rapid Multi-Enzyme; detergent 2, Scopezime; and detergent 3, Intercept) for 3, 5, and 7 minutes. Escherichia coli viable counts and biofilm changes were measured by colony counting and electron microscopy scanning, respectively.Statistical differences were observed between various detergents and the control group (P.001) but not among the different contact time groups (3, 5, and 7 minutes, P.05). Multiple comparisons showed that statistical differences in residual biofilm bacteria were observed between the detergents and the control (P.001). Significant differences (P.001) in residual biofilm bacteria existed between the 2 enzymatic detergents and the nonenzymatic detergent group, whereas no significant difference was observed between the 2 enzymatic detergents (P.05). No crossover effect was observed between various detergent groups, contact time, and the control group (P.05). Electron microscopy scanning revealed that, after various detergents and contact time of 3, 5, and 7 minutes, the residual biofilm in the enzymatic detergent group was significantly more than that of the nonenzymatic detergent group. No significant difference was observed among the groups with the same detergent and different contact time.Significantly more biofilm bacteria and biofilms were found in the enzymatic detergent groups compared with the nonenzymatic detergent group, whereas no significant difference was observed among 3, 5, and 7 minutes groups.

Single-nucleus gene expression Identifying the genes expressed at the level of a single cell nucleus can better help us understand the human brain. Blue et al. developed a single-nuclei sequencing technique, which they applied to cells in classically defined Brodmann areas from a postmortem brain. Clustering of gene expression showed concordance with the area of origin and defining 16 neuronal subtypes. Both excitatory and inhibitory neuronal subtypes show regional variations that define distinct cortical areas and exhibit how gene expression clusters may distinguish between distinct cortical areas. This method opens the door to widespread sampling of the genes expressed in a diseased brain and other tissues of interest. Science , this issue p. 1586

Purpose: The difficulties of fluid therapy in patients with septic shock are to maintain sufficient vascular volume while preventing pulmonary edema formation. Thus, it is important to find a biomarker that can reliably predict pulmonary edema formation after fluid loading. We evaluated the association of plasma protein levels with the increase in extravascular lung water index (ΔEVLWI) after fluid loading. Methods: This was an observational study in which we retrospectively reviewed medical records of septic patients in whom hemodynamic variables were measured by transpulmonary thermodilution technique before and after fluid loading. Plasma protein levels were measured before fluid loading. Patients were divided into 2 groups according to the changes in EVLWI (ΔEVLWI ≥10%) after fluid loading. Diagnostic performance of plasma proteins in predicting pulmonary edema formation was assessed. Results:Atotal of 62patients were included, and 27ofthem showed a ΔEVLWI 10%or higherafter fluid loading. Plasma albumin and transferrin were significantly lower in this group than in the group with ΔEVLWI less than 10% (21.7 ± 5.8 vs 25.3 ± 5.0 g/L for albumin, P b .05; 107.9 ± 50.1 vs 136.8 ± 44.2 mg/dL for transferrin, P b .05). Areas under the curve of albumin and transferrin were 0.68 (cardiac index, 0.54-0.83) and 0.72 (cardiac index, 0.59-0.86), respectively. At a cutoff value of 87.9 mg/dL, transferrin had a sensitivity of 0.91 in predicting ΔEVLWI 10% or higher. Conclusions: Plasma transferrin and albumin levels were associated with ΔEVLWI 10% or higher after fluid loading. The high sensitivity of both biomarkers indicated that patients with normal values were less likely to develop pulmonary edema after fluid loading.

Stroke volume variation (SVV) appears to be a good predictor of fluid responsiveness in critically ill patients. However, a wide range of its predictive values has been reported in recent years. We therefore undertook a systematic review and meta-analysis of clinical trials that investigated the diagnostic value of SVV in predicting fluid responsiveness.Clinical investigations were identified from several sources, including MEDLINE, EMBASE, WANFANG, and CENTRAL. Original articles investigating the diagnostic value of SVV in predicting fluid responsiveness were considered to be eligible. Participants included critically ill patients in the intensive care unit (ICU) or operating room (OR) who require hemodynamic monitoring.A total of 568 patients from 23 studies were included in our final analysis. Baseline SVV was correlated to fluid responsiveness with a pooled correlation coefficient of 0.718. Across all settings, we found a diagnostic odds ratio of 18.4 for SVV to predict fluid responsiveness at a sensitivity of 0.81 and specificity of 0.80. The SVV was of diagnostic value for fluid responsiveness in OR or ICU patients monitored with the PiCCO or the FloTrac/Vigileo system, and in patients ventilated with tidal volume greater than 8 ml/kg.SVV is of diagnostic value in predicting fluid responsiveness in various settings.

Mesoporous MCM-41 silica functionalized with sulfonic acid groups (SO 3 H-MCM-41) was prepared through the condensation of MCM-41 with benzyl alcohol followed with sulfonation, which was characterized by XRD, FT-IR and nitrogen adsorption analyses. One-pot Fischer indole synthesis of tryptophols under the catalysis of SO 3 H-MCM-41 was reported with phenylhydrazine hydrochlorides and 2,3-dihydrofuran. The acidity and amount of sulfur loading were surveyed and also were the catalytic performance of SO 3 H-MCM-41. The results showed that higher amount of sulfur loading leads to higher acidity and consequently better yields of tryptophols. Moreover, SO 3 H-MCM-41 displayed good shape-selectivity in Fischer indole synthesis and inhibited the production of bulky byproduct polyindoles which were generally found in traditional acid catalysis. A series of tryptophols were synthesized with SO 3 H-MCM-41 in better yields than those of conventional methods reported.

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity, insulin resistance, and inflammatory disorders. In this study, we tested the effect of rhein, a lipophilic anthraquinone derived from a traditional Chinese herbal medicine Rheum palmatum L., on NAFLD-associated hepatic steatosis, insulin resistance, and the T helper (Th)1/Th2 cytokine imbalance in high-fat diet-induced obese (DIO) mice. We found that oral administration of rhein for 40 days significantly increased energy expenditure, reduced body weight, particularly body fat content, improved insulin resistance, and lowered circulating cholesterol levels in DIO mice without affecting food intake. Rhein treatment also reduced liver triglyceride levels, reversed hepatic steatosis, and normalized alanine aminotransferase (ALT) levels in these mice. Gene analysis and Western blot showed that rhein markedly suppressed the expression of the lipogenic enzyme sterol regulatory element-binding protein-1c (SREBP-1c) and its target genes in the liver. Luciferase reporter assay revealed that rhein suppressed the transcriptional activity of SREBP-1c through its upstream regulator, liver X receptor (LXR). This suggests that rhein exerts its effects by targeting LXR, which is also supported by its inability to reduce body weight in LXR knockout mice. Moreover, multiplex ELISA displayed a downregulated Th1 response after rhein treatment. Rhein shifted the Th1/Th2 responses by inhibiting T-box expressed in T-cells (T-bet) expression and enhancing GATA-binding protein-3 (GATA-3) expression through increased signal transducer and activator of transcription 6 (STAT6) phosphorylation. These data indicate that rhein ameliorated NAFLD and associated disorders through LXR-mediated negative energy balance, metabolic regulatory pathways, and immunomodulatory activities involved in hepatic steatosis. The combined effects of rhein to target hepatic metabolic and immune pathways may be beneficial for complex metabolic diseases such as NAFLD.

Immunization with inactivated autoreactive T cells is an effective therapeutic approach to ameliorating autoimmune diseases, while the underlying mechanisms that regulate autoreactive T cells are not completely understood. This study tested the hypothesis that T-cell vaccination (TCV) inhibits autoimmune diabetes in mice through the suppression of Th17 cells. The results showed that TCV treatment decreased hyperglycemia in type 1 diabetes (T1D) induced by multiple low-dose streptozotocin (MLD-STZ) as compared with the controls, preserved the number of healthy pancreatic islets and increased the production of insulin in the islets. Further study revealed that TCV significantly decreased the production of both interleukin (IL)-17 and IL-23 in intrapancreatic infiltrating lymphocytes (IPL) through marked inhibition of mRNA level of retinoic acid-related orphan receptor γt (RORγt) and signal transducer and activator of transcription 3 (Stat3) phosphorylation. The role of TCV-induced Th17 suppression was further validated in adoptive transfer experiments with polarized Th17 cells in sub-diabetogenic mice, which was similar to the effect of anti-IL-17 antibody treatment. Collectively our study shows that intrapancreatic Th17 cell suppression and healthy islet preservation play an important role in the treatment of T1D by TCV.

Th17 cells are a subset of CD4+ T cells with an important role in clearing certain bacterial and fungal pathogens. However, they have also been implicated in autoimmune diseases such as multiple sclerosis. Exposure of naive CD4+ T cells to IL-6 and TGF-β leads to Th17 cell differentiation through a process in which many proteins have been implicated. We report here that ectopic expression of liver X receptor (LXR) inhibits Th17 polarization of mouse CD4+ T cells, while LXR deficiency promotes Th17 differentiation in vitro. LXR activation in mice ameliorated disease in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis, whereas LXR deficiency exacerbated disease. Further analysis revealed that Srebp-1, which is encoded by an LXR target gene, mediated the suppression of Th17 differentiation by binding to the E-box element on the Il17 promoter, physically interacting with aryl hydrocarbon receptor (Ahr) and inhibiting Ahr-controlled Il17 transcription. The putative active site (PAS) domain of Ahr and the N-terminal acidic region of Srebp-1 were essential for this interaction. Additional analyses suggested that similar LXR-dependent mechanisms were operational during human Th17 differentiation in vitro. This study reports what we believe to be a novel signaling pathway underlying LXR-mediated regulation of Th17 cell differentiation and autoimmunity.

Members of the CENTRORADIALIS (CEN)/TERMINAL FLOWER 1 (TFL1) subfamily control shoot meristem identity, and loss-of-function mutations in both monopodial and sympodial herbaceous plants result in dramatic changes in plant architecture. We studied the degree of conservation between herbaceous and woody perennial plants in shoot system regulation by overexpression and RNA interference (RNAi)-mediated suppression of poplar orthologs of CEN, and the related gene MOTHER OF FT AND TFL 1 (MFT). Field study of transgenic poplars (Populus spp.) for over 6 years showed that downregulation of PopCEN1 and its close paralog, PopCEN2, accelerated the onset of mature tree characteristics, including age of first flowering, number of inflorescences and proportion of short shoots. Surprisingly, terminal vegetative meristems remained indeterminate in PopCEN1-RNAi trees, suggesting the possibility that florigen signals are transported to axillary mersitems rather than the shoot apex. However, the axillary inflorescences (catkins) of PopCEN1-RNAi trees contained fewer flowers than did wild-type catkins, suggesting a possible role in maintaining the indeterminacy of the inflorescence apex. Expression of PopCEN1 was significantly correlated with delayed spring bud flush in multiple years, and in controlled environment experiments, 35S::PopCEN1 and RNAi transgenics required different chilling times to release dormancy. Considered together, these results indicate that PopCEN1/PopCEN2 help to integrate shoot developmental transitions that recur during each seasonal cycle with the age-related changes that occur over years of growth.

Bacterial two-component regulatory systems (TCS) are common components of complex regulatory networks and cascades. In Sinorhizobium meliloti, the TCS ExoS/ChvI controls exopolysaccharide succinoglycan production and flagellum biosynthesis. Although this system plays a crucial role in establishing the symbiosis between S. meliloti and its host plant, it is not well characterized. Attempts to generate complete loss-of-function mutations in either exoS or chvI in S. meliloti have been unsuccessful; thus, it was previously suggested that exoS or chvI are essential genes for bacterial cell growth. We constructed a chvI mutant by completely deleting the open reading frame encoding this gene. The mutant strain failed to grow on complex medium, exhibited lower tolerance to acidic condition, produced significantly less poly-3-hydroxybutyrate than the wild type, was hypermotile, and exhibited an altered lipopolysaccharide profile. In addition, this mutant was defective in symbiosis with Medicago truncatula and M. sativa (alfalfa), although it induced root hair deformation as efficiently as the wild type. Together, our results demonstrate that ChvI is intimately involved in regulatory networks involving the cell envelope and metabolism; however, its precise role within the regulatory network remains to be determined.

Peroxisome proliferator-activated receptor (PPAR) gamma is a nuclear receptor that coordinates carbohydrate and lipid metabolism, and is a therapeutic target for type 2 diabetes. Tanshinone IIA (Tan) is a lipophilic diterpene that is widely used to treat cardiovascular diseases in traditional Chinese medicine, and has recently been found to reduce body weight and lower blood lipids. However, its underlying mechanism of antiadipogenic effects remains unknown. Here, we report that Tan inhibits 3T3-L1 preadipocyte differentiation and transcriptional activities of full-length PPARgamma and PPARgamma ligand-binding domains. The effects of Tan are mediated through its property as a natural antagonist of PPARgamma (dissociation constant of an inhibitor value, 2.562 +/- 0.711 microm). Tan treatment reduced adipose mass and body weight, improved glucose tolerance, and lowered the low-density lipoprotein to high-density lipoprotein ratio without changing the food intake in a high-fat diet-induced obese animal model. Our results suggest that the combined properties of Tan in adipogenesis, glucose tolerance, lipogenesis, and cardiovascular protection are beneficial for treating diabetic patients with complex metabolic conditions, in which modulating a single target is often not sufficient to achieve the desired effect.

A similarity analysis for Marangoni convection induced flow over a vapor-liquid interface due to an imposed temperature gradient was carried out. The analysis assumes that the surface tension varies linearly with temperature but the temperature variation is a power law function of the location. The similarity solutions are presented numerically and the associated transfer characteristics are discussed.

Type I diabetes is characterized by the deficiency of endocrine beta cells in the pancreatic islets of Langerhans and transplantation of islet cells can be an effective therapeutic approach. Embryonic stem cells can be differentiated into any cell type, and therefore represent an unlimited source of islet cells for the transplantation and treatment for type I diabetes. We have adopted an easy and reproducible in vitro differentiation system with a reduced serum concentration plus nicotinamide to generate early pancreatic progenitor cells from embryonic stem cells. Gene expression analysis indicated that the differentiated cells expressed not only endoderm markers such as GATA-4, HNF-3beta, but also early markers of pancreatic development including key transcription factors PDX-1 and IAPP. Some pancreatic specific markers, such as insulin I, insulin II, Glu-2 and glucagon, were also expressed to some extent at the mRNA level. Differentiated ES cells showed low level immunoreactivity for insulin. However, transplantation of these early pancreatic progenitor clusters into STZ-induced diabetic mice failed to reverse the hyperglycemic state of the disease as reported previously. The results suggest that culture manipulation can direct ES cells to differentiate into early pancreatic progenitor cells committing to pancreatic islet cell fate, but these cells cannot function normally to reduce blood glucose of diabetic mice at this stage.

Poly-3-hydroxybutyrate (PHB) and glycogen are major carbon storage compounds in Sinorhizobium meliloti. The roles of PHB and glycogen in rhizobia-legume symbiosis are not fully understood. Glycogen synthase mutations were constructed by in-frame deletion (glgA1) or insertion (glgA2). These mutations were combined with a phbC mutation to make all combinations of double and triple mutants. PHB was not detectable in any of the mutants containing the phbC mutation; glycogen was not detectable in any of the mutants containing the glgA1 mutation. PHB levels were significantly lower in the glgA1 mutant, while glycogen levels were increased in the phbC mutant. Exopolysaccharide (EPS) was not detected in any of the phbC mutants, while the glgA1 and glgA2 mutants produced levels of EPS similar to the wild-type. Symbiotic properties of these strains were investigated on Medicago truncatula and Medicago sativa. The results indicated that the strains unable to synthesize PHB, or glycogen, were still able to form nodules and fix nitrogen. However, phbC mutations caused greater nodule formation delay on M. truncatula than on M. sativa. Time-course studies showed that (1) the ability to synthesize PHB is important for N(2) fixation in M. truncatula nodules and younger M. sativa nodules, and (2) the blocking of glycogen synthesis resulted in lower levels of N(2) fixation on M. truncatula and older nodules on M. sativa. These data have important implications for understanding how PHB and glycogen function in the interactions of S. meliloti with Medicago spp.

Berberine (BBR), a compound purified from Cortidis rhizoma, reduces serum cholesterol, triglycerides, and LDL-cholesterol of hypercholesterolemic patients and high fat diet fed animals, and increases hepatic LDLR mRNA and protein levels through a post-transcriptional mechanism. BBR also enhances the hypoglycemic action of insulin in diabetic animal models. Here, we show that BBR inhibits the differentiation of 3T3-L1 preadipocytes induced by DM and suppresses the mitotic clonal expansion of 3T3-L1 preadipocytes in a time- and dose-dependent manner. Gene expression analysis and Western blot analysis reveal that the BBR inhibits the mRNA and protein levels of adipogenesis related transcription factors PPARgamma and C/EBPalpha and their upstream regulator, C/EBPbeta. Reporter gene assays demonstrate that the full-length PPARgamma and alpha transcription activities are inhibited by BBR. Using real-time PCR, we have also found that the PPAR target genes that are involved in adipocyte differentiation, such as aP2, CD36, ACO, LPL, and other adipocyte markers, are suppressed by BBR. These studies suggest that BBR works on multiple molecular targets as an inhibitor of PPARgamma and alpha, and is a potential weight reducing, hypolipidemic, and hypoglycemic drug.

Similarities have long been recognized between vernalization, the prolonged exposure to cold temperatures that promotes the floral transition in many plants, and the chilling requirement to release bud dormancy in woody plants of temperate climates. In both cases the extended chilling period occurring during winter is used to coordinate developmental events to the appropriate seasonal time. However, whether or not these processes share common regulatory components and molecular mechanisms remain largely unknown. Both gene function and association genetics studies in Populus are beginning to answer this question. In Populus, studies have revealed that orthologs of the antagonistic flowering time genes FT and CEN/TFL1 might have central roles in both processes. We review Populus seasonal shoot development related to dormancy release and the floral transition and evidence for FT/TFL1-mediated regulation of these processes to consider the question of regulatory overlap. In addition, we discuss the potential for and challenges to integrating functional and population genomics studies to uncover the regulatory mechanisms underpinning these processes in woody plant systems. BioEnergy Science Center, a US Department of Energy (DOE) Bioenergy Research Center - Office of Biological and Environmental Research (BER) in the DOE Office of Science, DOE Office of Science (BER) [DE-SC0012574] Virginia Agricultural Experiment Station McIntire Stennis Program of the National Institute of Food and Agriculture, US Department of Agriculture This work was supported by the BioEnergy Science Center, a US Department of Energy (DOE) Bioenergy Research Center supported by the Office of Biological and Environmental Research (BER) in the DOE Office of Science, DOE Office of Science (BER) Grant No. DE-SC0012574, and the Virginia Agricultural Experiment Station and the McIntire Stennis Program of the National Institute of Food and Agriculture, US Department of Agriculture.

Gene repression by transcription factors, and glucocorticoid receptors (GR) in particular, is a critical, but poorly understood, physiological response. Among the many unresolved questions is the difference between GR regulated induction and repression, and whether transcription cofactor action is the same in both. Because activity classifications based on changes in gene product level are mechanistically uninformative, we present a theory for gene repression in which the mechanisms of factor action are defined kinetically and are consistent for both gene repression and induction. The theory is generally applicable and amenable to predictions if the dose-response curve for gene repression is non-cooperative with a unit Hill coefficient, which is observed for GR-regulated repression of AP1LUC reporter induction by phorbol myristate acetate. The theory predicts the mechanism of GR and cofactors, and where they act with respect to each other, based on how each cofactor alters the plots of various kinetic parameters vs. cofactor. We show that the kinetically-defined mechanism of action of each of four factors (reporter gene, p160 coactivator TIF2, and two pharmaceuticals [NU6027 and phenanthroline]) is the same in GR-regulated repression and induction. What differs is the position of GR action. This insight should simplify clinical efforts to differentially modulate factor actions in gene induction vs. gene repression., Author Summary While the initial steps in steroid-regulated gene induction and repression are known to be identical, the same cannot be said of cofactors that modulate steroid-regulated gene activity. We describe the conditions under which a theoretical model for gene repression reveals the kinetically-defined mechanism and relative position of cofactor action. This theory has been validated by experimental results with glucocorticoid receptors. The mode and position of action of four factors is qualitatively identical in gene repression to that previously found in gene induction. What changes is the position of GR action. Therefore, we predict that the same kinetically-defined mechanism usually will be utilized by cofactors in both induction and repression pathways. This insight and simplification should facilitate clinical efforts to maximize desired outcomes in gene induction or repression.

(R)-(3,5,6-Trimethylpyrazinyl) methyl-2-acetoxy-3-(3,4-diacetoxyphenyl) propanoate (ADTM) is a novel Danshensu (DSS) derivative regarded as a potential new agent for the treatment of myocardial ischemia. A validated high performance liquid chromatography (HPLC) approach with a detection limit of 5 ng/mL was used for pharmacokinetic evaluation of ADTM in rat plasma. The intra- and interday precision in terms of relative standard deviation were

To investigate the incidence of constipation after stroke and explore the relationship between post-stroke constipation and brain injury.Using a self-designed questionnaire, we collected the general information of 723 inpatients from 10 hospitals in Guangzhou, including the general demographic information, related factors of brain injury, defecation and previous history.The total incidence of post-stroke constipation was 34.6% in these patients. The incidence of constipation was 31.0% in ischemic stroke patients, 44.8% in hemorrhagic stroke patients, and 47.4% in patients with cerebral hemorrhage and infarction, showing a significant difference between stroke types (χ(2)=12.369, P=0.002). In terms of stages following stroke, the incidence was 41.6% in the acute phase, 31.5% in the recovery phase, and 22.6% in the sequelae phase. In light of lesion locations, the incidence was significantly higher in patients with basal ganglia involvement than in those without (P0.001). Logistic multivariate analyses showed that stroke type, post-stroke stage, lesion number and basal ganglia involvement were significantly associated with the incidence of constipation.Constipation often occurs in the acute stage following stroke (especially hemorrhagic stroke), and the incidence is higher in patients with basal ganglia involvement.

Sepsis is a leading cause of morbidity and mortality in the critical care setting. Millions of people are affected by this devastating illness each year, and it is reported that at least 1 in 4 of such patients will die from this disease (1, 2). Patho-physiologically, sepsis is characterized by uncontrolled sys-temic inflammatory responses and subsequent increases in vascular permeability to plasma protein triggered by inflam-matory mediators (3, 4), resulting in loss of plasma volume, increase in extravascular lung water (EVLW), hypotension, multiorgan failure, shock and even death. Acute kidney in-jury (AKI) is a life-threatening complication of severe sepsis. As demonstrated by Chertow et al (5), even mild forms of AKI (>0.5 mg/dL increase in serum creatinine) were associ-ated with a sevenfold increase in mortality. Despite recent advances in management of septic AKI, the morbidity and mortality rates for this disease entity have not been substan-tially improved. Treatment failure is largely due to the lack of a reliable biomarker for early recognition of AKI. Serum creatinine (sCr)–based evaluation of renal function lags be-hind renal injury because sCr rises only after more than 50% kidney function has been lost (6). It is proposed that AKI can be prevented and treated if adequate strategies have been taken early after renal insult. Thus, early recognition of renal injury after insult is clinically important and potentially useful to improve clinical outcomes (7). Microalbuminuria (MA), typically defined as albumin excre-tion in urine of 30-300 mg/24 hours, occurs rapidly after acute inflammatory insult and is shown to be associated with outcomes in many clinical settings, including sepsis, multiple trauma and intracranial hemorrhage (8-10). The mechanisms of MA development have been extensively

Liver X receptors (LXRs) play important roles in regulating cholesterol homeostasis, and lipid and energy metabolism. Therefore, LXR ligands could be used for the management of metabolic disorders. We evaluated rhein, a natural compound from Rheum palmatum L., as an antagonist for LXRs and investigated its anti-obesity mechanism in high-fat diet-fed mice. Surface plasmon resonance assays were performed to examine the direct binding of rhein to LXRs. LXR target gene expression was assessed in 3T3-L1 adipocytes and HepG2 hepatic cells in vitro. C57BL/6J mice fed a high-fat diet were orally administered with rhein for 4 weeks, and then the expression levels of LXR-related genes were analyzed. Rhein bound directly to LXRs. The expression levels of LXR target genes were suppressed by rhein in 3T3-L1 and HepG2 cells. In white adipose tissue, muscle and liver, rhein reprogrammed the expression of LXR target genes related to adipogenesis and cholesterol metabolism. Rhein activated uncoupling protein 1 (UCP1) expression in brown adipose tissue (BAT) in wild-type mice, but did not affect UCP1 expression in LXR knockout mice. In HIB-1B brown adipocytes, rhein activated the UCP1 gene by antagonizing the repressive effect of LXR on UCP1 expression. This study suggests that rhein may protect against obesity and related metabolic disorders through LXR antagonism and regulation of UCP1 expression in BAT.

Shoot phenology interacts with crown morphology to determine leaf production and duration over the growing season and throughout a tree’s life span; and thus, this interaction has a major role in determining whole-tree photosynthesis and biomass yield. For several years, the pattern of shoot meristem activity determines Populus crown architecture, but after the first onset of flowering the specification of meristem identity (inflorescence vs. vegetative) also has a major influence on crown form. To study how shoot meristem activity and identity are regulated in Populus, we are focusing on two pathways that have been extensively characterized in annual plants: 1) the MORE AXILLARY BRANCHING (MAX) genes that are involved in the synthesis and perception of upwardly mobile strigolactones that inhibit axillary bud outgrowth, and 2) members of the TERMINAL FLOWER1 (TFL1)/FLOWERING LOCUS T (FT) and APETALA1(AP1)/FRUITFULL(FUL) gene families that regulate flowering. We are taking a multi-pronged approach that includes field and controlled-environment study of poplar transgenics, transcriptome analyses, cell-specific expression studies, and QTL and association mapping. QTL mapping in a hybrid poplar pedigree localized three of seven poplar MAX genes in QTL for bud set and two MAX genes in sylleptic branching QTL. All MAX transgenics were established in a field trial and phenotyping of phenology, crown morphology, and growth is in progress. Greenhouse studies of poplar transgenics with the seven different poplar MAX gene promoters driving the reporter gene GUS show that most of the MAX genes are expressed in vascular tissues. However, vascular expression patterns are different, especially in stems undergoing secondary growth. Surprisingly, none of the RNAi transgenics showed differences in branching in the greenhouse under standard growing conditions. High nitrogen levels can induce sylleptic branching in poplar and greenhouse experiments with MAX transgenics indicate a possible role for one MAX gene in nitrogen-induced sylleptic branching. Ongoing studies of the effects of decapitation of the shoot apex with and without subsequent auxin application to the cut stem indicate that, as predicted based on studies in annual plants, the poplar MAX RNAi transgenics show a reduced response to apically-applied auxin. Recent work has revealed that poplar FT1 and FT2 have diverged in regulation and function with FT1 promoting the transition to flowering in response to winter temperatures, whereas warm temperatures and long days promote FT2 expression and shoot growth [1]. In Arabidopsis, FT activates AP1, a key regulator of flower initiation. Expression and transgenic studies in poplar indicate that similar to the two poplar FTs, poplar AP1 subfamily members have roles in both flowering and bud set in response to short-days and abiotic stress. Ongoing work is aimed at defining the roles of FT and AP1 modules in these processes and to delineate the roles of the five different poplar AP1/FUL genes. Finally, TFL1 acts opposite to FT to promote vegetative meristem identity in Arabidopsis, and AP1 and TFL1 repress each other’s expression. The poplar TFL1 homologs, CEN1 and/or CEN2 have roles in maintaining vegetative identity and in the dormancy-growth transition [2] and we are currently working to define the individual roles of the poplar CENs and their relationships to FT and AP1 activities.

More and more office buildings are built andconsequently£¬ the building energy-consumption increases especially air conditioning energy consumption. The energy consumption of air conditioning is monitored in an office building in Qingdao, and the test results show that refrigerator installed capacity is too large and COP is low, cooling circle pumps and chilled water pumps are oversize and water transport factor is lower than the standard value, the efficiency of the cooling tower is also very low. Based on experimental result, corresponding energy saving measures are proposed.

Background: Cystatin C (CysC) has been proposed as a filtration marker for the early detection of acute kidney injury (AKI); however, a wide range of its predictive accuracy has been reported. Study Design: Meta-analysis of diagnostic test studies. Setting & Population: Various clinical settings of AKI, including patients after cardiac surgery, pediatric patients, and critically ill patients. Selection Criteria: Computerized search of PubMed, Current Contents, CINAHL, and EMBASE from inception until November 15, 2010, was performed to identify potentially relevant articles. Inclusion criteria were studies investigating the diagnostic accuracy of CysC level to predict AKI. There were no language restrictions in the search. Index Tests: Increasing or increased serum CysC level or urinary CysC excretion. Reference Tests: The outcome was the development of AKI, primarily based on serum creatinine level (definition varied across studies). Results: We analyzed data from 19 studies and 11 countries involving 3,336 patients. Of these studies, 13 could be included in the meta-analysis. Across all settings, the diagnostic OR for serum CysC level to predict AKI was 23.5 (95% CI, 14.2-38.9), with sensitivity and specificity of 0.84 and 0.82, respectively. The area under the receiver operating characteristic curve (AUROC) of serum CysC level to predict AKI was 0.96 (95% CI, 0.95-0.97). Subgroup analysis showed that serum CysC was of diagnostic value when measured early (within 24 hours after renal insult or intensive care unit admission). For the diagnostic value of urinary CysC excretion, the diagnostic OR was 2.60 (95% CI, 2.01-3.35), with sensitivity and specificity of 0.52 and 0.70, respectively. The AUROC of urinary CysC excretion to predict AKI was 0.64 (95% CI, 0.62-0.66). Limitations: Variation in criteria for definitions of index and reference tests, absence of measured glomerular filtration rate in most studies. Conclusion: Serum CysC appears to be a good biomarker in the prediction of AKI, whereas urinary CysC excretion has only moderate diagnostic value. Am J Kidney Dis. 58(3):356-365. © 2011 by the National Kidney Foundation, Inc.

Along with the acceleration of the urbanization process in China? the ratio of building energy consumption to the commercial energy remains high, which is becoming more prominent on the national economy development and people's normal life. The problem that government office buildings and large public buildings with high energy consumption has become a major issue to the socio-economic development. The energy saving measures to China's large public buildings must be taken. In this paper, a large public building energy consumption clausal measurement & real-time monitoring system EMS-?(EMS-?)developed by Tsinghua University has a real-time sub-metering to monitor energy consumption of a large public building in Qingdao. It provides the basis data and relevant reference for the stipulation of building energy analysis and building energy saving standards in Qingdao and the country.

Batch fermentative production of fumaric acid by Rhizopus oryzae ME-F12 was investigated in a 7-l stirred tank fermentor under different dissolved oxygen (DO) concentrations. High fumaric acid yield on glucose (0.56 g/g) was achieved under high DO concentration (80%), but the glucose consumption rate and fumaric acid productivity were rather low (0.91 and 0.51 g/l/h). Fumaric acid productivity was enhanced under low DO concentration (30%), but the fuamric acid yield on glucose decreased to 0.52 g/g. In order to achieve the high fumaric acid yield and productivity simultaneously, a two-stage dissolved oxygen control strategy was proposed, in which the DO concentration was controlled at 80% in the first 18 h and then switched to 30%. This was experimentally proven to be successful. Relatively high fumaric acid production (56.2 g/l), high fumaric acid yield on glucose (0.54 g/g), and high glucose consumption rate (1.3 g/l/h) were achieved by applying this strategy. The productivity (0.7 g/l/h) was improved by 37%, 21%, and 9%, respectively, compared with fermentations in which DO concentrations were kept constant at 80%, 60%, and 30%.

Lecithin is an essential biological component and widely used as a nutritional supplement for protecting cells from oxidation, increase fat burning and preventing cardiovascular disease. Lecithin contains fatty acids identified as the peroxisome proliferator-activated receptor (PPAR) agonists. However, the role of lecithin in adipogenesis and lipogenesis remains elusive. 3T3-L1 cells and mouse primary preadipocytes were used to characterize the properties of lecithin related to adipogenesis and lipogenesis. We found that lecithin promoted adipocyte differentiation and differentiation-specific gene expression, and increased triglycerides and free fatty acid levels in the adipocytes. These effects are independent of the clonal expansion of 3T3-L1 cells and the upstream PPARgamma regulator, CCAAT-enhancer-binding protein beta. Furthermore, lecithin induced lipid accumulation in human hepatoma HepG2 cells. Our data suggest that lecithin is involved in adipogenesis, lipogenesis and hepatic lipid accumulation and it is implicated in obesity and hepatic steatosis.

Peroxisome proliferator-activated receptors (PPARs) are transcriptional factors involved in the regulation of insulin resistance and adipogenesis. Cinnamon, a widely used spice in food preparation and traditional antidiabetic remedy, is found to activate PPARγandα, resulting in improved insulin resistance, reduced fasted glucose, FFA, LDL-c, and AST levels in high-caloric diet-induced obesity (DIO) anddb/dbmice in its water extract form. In vitro studies demonstrate that cinnamon increases the expression of peroxisome proliferator-activated receptorsγandα(PPARγ/α) and their target genes such as LPL, CD36, GLUT4, and ACO in 3T3-L1 adipocyte. The transactivities of both full length and ligand-binding domain (LBD) of PPARγand PPARαare activated by cinnamon as evidenced by reporter gene assays. These data suggest that cinnamon in its water extract form can act as a dual activator of PPARγandα, and may be an alternative to PPARγactivator in managing obesity-related diabetes and hyperlipidemia.

Sinorhizobium meliloti cells store excess carbon as intracellular poly-3-hydroxybutyrate (PHB) granules that assist survival under fluctuating nutritional conditions. PHB granule-associated proteins (phasins) are proposed to regulate PHB synthesis and granule formation. Although the enzymology and genetics of PHB metabolism in S. meliloti have been well characterized, phasins have not yet been described for this organism. Comparison of the protein profiles of the wild type and a PHB synthesis mutant revealed two major proteins absent from the mutant. These were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) as being encoded by the SMc00777 ( phaP1 ) and SMc02111 ( phaP2 ) genes. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins associated with PHB granules followed by MALDI-TOF confirmed that PhaP1 and PhaP2 were the two major phasins. Double mutants were defective in PHB production, while single mutants still produced PHB, and unlike PHB synthesis mutants that have reduced exopolysaccharide, the double mutants had higher exopolysaccharide levels. Medicago truncatula plants inoculated with the double mutant exhibited reduced shoot dry weight (SDW), although there was no corresponding reduction in nitrogen fixation activity. Whether the phasins are involved in a metabolic regulatory response or whether the reduced SDW is due to a reduction in assimilation of fixed nitrogen rather than a reduction in nitrogen fixation activity remains to be established.

A cDNA library was constructed from leaf epidermis of diploid wheat (Triticum monococcum) infected with the powdery mildew fungus (Blumeria graminis f. sp. tritici) and was screened for genes encoding peroxidases. From 2,500 expressed sequence tags (ESTs), 36 cDNAs representing 10 peroxidase genes (designated TmPRX1 to TmPRX10) were isolated and further characterized. Alignment of the deduced amino acid sequences and phylogenetic clustering with peroxidases from other plant species demonstrated that these peroxidases fall into four distinct groups. Differential expression and tissue-specific localization among the members were observed during the B. graminis f. sp. tritici attack using Northern blots and reverse-transcriptase polymerase chain reaction analyses. Consistent with its abundance in the EST collection, TmPRX1 expression showed the highest induction during pathogen attack and fluctuated in response to the fungal parasitic stages. TmPRX1 to TmPRX6 were expressed predominantly in mesophyll cells, whereas TmPRX7 to TmPRX10, which feature a putative C-terminal propeptide, were detectable mainly in epidermal cells. Using TmPRX8 as a representative, we demonstrated that its C-terminal propeptide was sufficient to target a green fluorescent protein fusion protein to the vacuoles in onion cells. Finally, differential expression profiles of the TmPRXs after abiotic stresses and signal molecule treatments were used to dissect the potential role of these peroxidases in multiple stress and defense pathways. Additional keywords: cell wall appositions (CWAs), papilla, reactive oxygen species (ROS).

Poly-3-hydroxybutyrate (PHB) and glycogen are major carbon storage compounds in Sinorhizobium meliloti. The roles of PHB and glycogen in rhizobia-legume symbiosis are not fully understood (1, 2, 3). Bacteroids with determinate nodules often accumulate high levels of PHB (up to 70% dry weight) (1). In contrast, bacteroids within indeterminate nodules do not accumulate PHB. In the symbiosis between S. meliloti and alfalfa, it has been reported that phbC mutants form bacteroids capable of fixing nitrogen as efficiently as the wild type (4, 5, 6), but are less competitive than wild type strain (5). There are two glycogen synthase-encoding genes in S. meliloti, glgA1 in a cluster of other glycogen synthesis pathway genes on the chromosome, and glgA2 on megaplasmid pSymb. Recently, it has been shown in Rhizobium tropici with Phaseolus vulgaris that there may be a link between glycogen synthase deficiency, decreased exopolysaccharide, and increased symbiotic performance (2). However, the reason for the increased symbiotic efficiency of the glgA mutant is uncertain (3). To determine the roles these compounds may play in the symbiotic process and in the overall physiology of the organism in the free-living and bacteroid states, mutants unable to synthesize PHB and/or glycogen were constructed. A glgA1 mutation was constructed by in-frame deletion, preserving the expression of the downstream pgm gene, while a glgA2 mutation was constructed by disruption of the gene with the Sp omega cassette (7). A pre-existing Tn5-generated mutation of the PHB synthase encoding gene phbC (8) was combined with glgA1 and glgA2 mutations to make all combinations of double mutants, and the triple mutant (Table 1). PHB was not detectable in free-living cells of any mutant containing the phbC mutation; glycogen was not detectable in any of the mutants containing the glgA1 mutation. The production of PHB decreased significantly in the glgA1 mutant (Rm11479), and the glgA double mutant (Rm11482). The production of glycogen increased significantly in the phbC mutant (Rm11105) in high carbon ratio media. Exopolysaccharide (EPS) was not detected in any of the mutants containing the phbC mutation, while the glgA double mutant (Rm11482) produced much more EPS in MOPS medium compared to the wild type (Rm1021), glgA1