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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

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.

Stem cell transplantation has been generally considered as promising therapeutics in preserving or recovering functions of lost, damaged, or aging tissues. Transplantation of primordial germ cells (PGCs) or oogonia stem cells (OSCs) can reconstitute ovarian functions that yet sustain for only short period of time, limiting potential application of stem cells in preservation of fertility and endocrine function. Here, we show that mTOR inhibition by INK128 extends the follicular and endocrine functions of the reconstituted ovaries in aging and premature aging mice following transplantation of PGCs/OSCs. Follicular development and endocrine functions of the reconstituted ovaries by transplanting PGCs into kidney capsule of the recipient mice were maintained by INK128 treatment for more than 12 weeks, in contrast to the controls for only about 4 weeks without receiving the mTOR inhibitors. Comparatively, rapamycin also can prolong the ovarian functions but for limited time. Furthermore, our data reveal that INK128 promotes mitochondrial function in addition to its known function in suppression of immune response and inflammation. Taken together, germline stem cell transplantation in combination with mTOR inhibition by INK128 improves and extends the reconstituted ovarian and endocrine functions in reproductive aging and premature aging mice., In this manuscript, Heng et al. report that mTOR inhibition by INK128 extends functions of ovarian reconstituted from transplantation of primordial germ cells/oogonia stem cells using various mouse models such as young mouse model, natural aging, premature aging mouse by knockout of telomerase, and immunodeficient mice. Moreover, INK128 greatly elevates mitochondria functions and suppresses inflammation and immunoresponses in the reconstituted ovaries.

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.