Treatment with BX471, a CC chemokine receptor 1 antagonist, attenuates systemic inflammatory response during sepsis

Sepsis is a complex clinical syndrome resulting from a harmful host inflammatory response to infection. Chemokines and their receptors play a key role in the pathogenesis of sepsis. BX471 is a potent nonpeptide CC chemokine receptor-1 (CCR1) antagonist in both human and mouse. The aim of the present study was to evaluate the effect of prophylactic and therapeutic treatment with BX471 on cecal ligation and puncture-induced sepsis in the mouse and to investigate the underlying mechanisms. In sepsis induced by cecal ligation and puncture, treatment with BX471 significantly protected mice against lung and liver injury by attenuating MPO activity, an indicator of neutrophil recruitment in lungs and livers and attenuating lung and liver morphological changes in histological sections. Blocking CCR1 by BX471 also downregulated ICAM-1, P-selectin, and E-selectin expression at mRNA and protein levels in lungs and livers compared with placebo-treated groups. These findings suggest that blockage of CCR1 by specific antagonist may represent a promising strategy to prevent disease progression in sepsis.     

Improving microbial fitness in the mammalian gut by in vivo temporal functional metagenomics

Elucidating functions of commensal microbial genes in the mammalian gut is challenging because many commensals are recalcitrant to laboratory cultivation and genetic manipulation. We present Temporal FUnctional Metagenomics sequencing (TFUMseq), a platform to functionally mine bacterial genomes for genes that contribute to fitness of commensal bacteria in vivo. Our approach uses metagenomic DNA to construct large‐scale heterologous expression libraries that are tracked over time in vivo by deep sequencing and computational methods. To demonstrate our approach, we built a TFUMseq plasmid library using the gut commensal Bacteroides thetaiotaomicron (Bt) and introduced Escherichia coli carrying this library into germfree mice. Population dynamics of library clones revealed Bt genes conferring significant fitness advantages in E. coli over time, including carbohydrate utilization genes, with a Bt galactokinase central to early colonization, and subsequent dominance by a Bt glycoside hydrolase enabling sucrose metabolism coupled with co‐evolution of the plasmid library and E. coli genome driving increased galactose utilization. Our findings highlight the utility of functional metagenomics for engineering commensal bacteria with improved properties, including expanded colonization capabilities in vivo.     

Abscisic acid-induced hydrogen peroxide is required for anthocyanin accumulation in leaves of rice seedlings

The role of hydrogen peroxide (H(2)O(2)) in abscisic acid (ABA)-induced anthocyanin accumulation in detached and intact leaves of rice seedlings was investigated. Treatment with ABA resulted in an accumulation of anthocyanins in detached rice leaves. Dimethylthiourea, a chemical trap for H(2)O(2), was observed to be effective in inhibiting ABA-induced accumulation of anthocyanins. Inhibitors of NADPH oxidase (diphenyleneiodonium chloride and imidazole), phosphatidylinositol 3-kinase (wortmannin and LY 294002), and a donor of nitric oxide (N-tert-butyl-alpha-phenylnitrone), which have previously been shown to prevent ABA-induced H(2)O(2) accumulation in detached rice leaves, inhibited ABA-induced anthocyanin increase. Exogenous application of H(2)O(2), however, was found to increase the anthocyanin content of detached rice leaves. In terms of H(2)O(2) accumulation, intact (attached) leaves of rice seedlings of cultivar Taichung Native 1 (TN1) are ABA sensitive and those of cultivar Tainung 67 (TNG67) are ABA insensitive. Upon treatment with ABA, H(2)O(2) and anthocyanins accumulated in leaves of TN1 seedlings but not in leaves of TNG67. Our results, obtained from detached and intact leaves of rice seedlings, suggest that H(2)O(2) is involved in ABA-induced anthocyanin accumulation in this species.     

New strategy for in vitro activation of primordial follicles with mTOR and PI3K stimulators

It had been known for decades that primordial follicles in mammalian ovaries are assembled with definite numbers and represent the ovarian reserve throughout the reproductive life. Intra-oocyte PI3K/mTOR pathways have been indicated to play a central role on the activation of primordial follicles. Genetic modified mouse models with chronic activation of PI3K/mTOR signals in primordial oocytes showed premature activation of all primordial follicles and eventually their exhaustion. On the other hand, this may suggest that, unlike chronic activation of PI3K/mTOR, its acute activation in infertility would activate primordial follicles, permitting fertility during the treatment. Previously, PI3K stimulators were reported as a temporary measure to accelerate primordial follicle activation and follicular development in both mouse and human, and were applied in the treatment of infertility in premature ovarian failure (POF) patients. To address whether mTOR stimulators could play similar role in the process, we transiently treated neonatal and aged mouse ovaries with mTOR stimulators-phosphatidic acid (PA) and propranolol. Our results demonstrated the stimulators increased activation of primordial follicles and the production of progeny. Human ovarian cortex cubes were also treated with mTOR or/and PI3K stimulators in vitro. When they were used separately, both of them showed similar promotive effects on primordial follicles. Surprisingly, after joint-treatment with the 2 kinds of stimulators together, synergistic effects on follicular development were observed. Based on increased efficiency of follicular activation in humans, here we propose in vitro transient treatment with mTOR and PI3K stimulators as an optimized protocol for the application in different clinical conditions with limited follicle reserve.     

Intratumoral expression of IL-17 and its prognostic role in gastric adenocarcinoma patients

In this study, we characterized the intratumoral expression of IL-17 and CD8(+) TILs in gastric adenocarcinoma patients after resection and determined the correlation between the survival probability of gastric adenocarcinoma patients and the expression of IL-17 in tumor. Expression of IL-17 and CD8 was assessed by immunohistochemistry, and the prognostic effects of intratumoral IL-17 expression and CD8(+) TILs were evaluated by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection revealed the presence of IL-17 and CD8(+) cells in gastric adenocarcinoma tissue samples (90.6%, 174 out of 192 patients and 96.9%, 186 out of 192 patients, respectively). We have also found that intratumoral IL-17 expression was significantly correlated with age (p=0.004) and that the number of CD8(+)TILs was significantly correlated with UICC staging (p=0.012) and the depth of tumor invasion (p=0.022). The five-year overall survival probability among patients intratumorally expressing higher levels of IL-17 was significantly better than those expressing lower levels of IL-17 (p=0.036). Multivariate Cox proportional hazard analyses revealed that intratumoral IL-17 expression (HR: 0.521; 95% CI: 0.329-0.823; p=0.005) was an independent factor affecting the five-year overall survival probability. We conclude that low levels of intratumoral IL-17 expression may indicate poor prognosis in gastric adenocarcinoma patients.     

Region-specific enhancement of basal extracellular and cocaine-evoked dopamine levels following constitutive deletion of the Serotonin(1B) receptor

The behavioral effects of cocaine are enhanced following constitutive deletion of the serotonin(1B) receptor. The neural substrates mediating the enhanced response to cocaine are unknown. The present studies determined whether basal dopamine dynamics or cocaine-evoked dopamine levels are altered in projection areas of mesostriatal or mesoaccumbens dopamine neurons following serotonin(1B) receptor deletion. Male wild-type and serotonin(1B) knockout mice were implanted with microdialysis guide cannulas aimed at the dorsal striatum or nucleus accumbens. The zero net flux method of quantitative microdialysis was used to quantify basal extracellular dopamine concentrations (DA(ext)) and the extraction fraction of dopamine (E(d)), which provides an index of dopamine uptake. Conventional microdialysis techniques were used to quantify cocaine (0, 5.0, and 20.0 mg/kg)-evoked dopamine overflow. Basal DA(ext) and E(d) did not differ in striatum of wild-type and knockout mice. Similarly, cocaine-stimulated dopamine overflow did not differ between genotype. The basal E(d) did not differ in the nucleus accumbens of wild-type and knockout mice. However, DA(ext) was significantly elevated in the nucleus accumbens of knockout mice. Cocaine-evoked dopamine overflow (nM) was also enhanced in the nucleus accumbens of knockout mice. However, the cocaine-induced increase in dopamine levels, relative to basal values, did not differ between genotype. These data demonstrate that deletion of the serotonin(1B) receptor is associated with increases in basal DA(ext) in the nucleus accumbens. This increase is not associated with an alteration in E(d), suggesting increased basal dopamine release in these animals. It is hypothesized that these alterations in presynaptic neuronal activity are a compensatory response to constitutive deletion of the serotonin(1B) receptor and may contribute to the enhanced behavioral effects of psychostimulants observed in knockout mice.     

Overexpression of an Arabidopsis magnesium transport gene, AtMGT1, in Nicotiana benthamiana confers Al tolerance

Aluminium (Al) toxicity is the most important limiting factor for crop production in acid soil environments worldwide. In some plant species, application of magnesium (Mg(2+)) can alleviate Al toxicity. However, it remains unknown whether overexpression of magnesium transport proteins can improve Al tolerance. Here, the role of AtMGT1, a member of the Arabidopsis magnesium transport family involved in Mg(2+) transport, played in Al tolerance in higher plants was investigated. Expression of 35S::AtMGT1 led to various phenotypic alterations in Nicotiana benthamiana plants. Transgenic plants harbouring 35S::AtMGT1 exhibited tolerance to Mg(2+) deficiency. Element assay showed that the contents of Mg, Mn, and Fe in 35S::AtMGT1 plants increased compared with wild-type plants. Root growth experiment revealed that 100 microM AlCl(3) caused a reduction in root elongation by 47% in transgenic lines, whereas root growth in wild-type plants was inhibited completely. Upon Al treatment, representative transgenic lines also showed a much lower callose deposition, an indicator of increased Al tolerance, than wild-type plants. Taken together, the results have demonstrated that overexpression of ATMGT1 encoding a magnesium transport protein can improve tolerance to Al in higher plants.     

Versican G3 promotes mouse mammary tumor cell growth, migration, and metastasis by influencing EGF receptor signaling

Increased versican expression in breast tumors is predictive of relapse and has negative impact on survival rates. The C-terminal G3 domain of versican influences local and systemic tumor invasiveness in pre-clinical murine models. However, the mechanism(s) by which G3 influences breast tumor growth and metastasis is not well characterized. Here we evaluated the expression of versican in mouse mammary tumor cell lines observing that 4T1 cells expressed highest levels while 66c14 cells expressed low levels. We exogenously expressed a G3 construct in 66c14 cells and analyzed its effects on cell proliferation, migration, cell cycle progression, and EGFR signaling. Experiments in a syngeneic orthotopic animal model demonstrated that G3 promoted tumor growth and systemic metastasis in vivo. Activation of pERK correlated with high levels of G3 expression. In vitro, G3 enhanced breast cancer cell proliferation and migration by up-regulating EGFR signaling, and enhanced cell motility through chemotactic mechanisms to bone stromal cells, which was prevented by inhibitor AG 1478. G3 expressing cells demonstrated increased CDK2 and GSK-3β (S9P) expression, which were related to cell growth. The activity of G3 on mouse mammary tumor cell growth, migration and its effect on spontaneous metastasis to bone in an orthotopic model was modulated by up-regulating the EGFR-mediated signaling pathway. Taken together, EGFR-signaling appears to be an important pathway in versican G3-mediated breast cancer tumor invasiveness and metastasis.     

空间异质性对样地数据空间外推的影响

应用模型结合的方法模拟了3个空间异质性等级预案下反应变量(气候变化下景观水平的树种分布面积)的变化情况,并分析模拟结果在预案之间的差异性,探讨了环境空间异质性对样地观测到的树种对气候变化响应向更大空间尺度外推的影响.结果表明：空间异质性在一般情况下对样地数据向土地类型尺度外推没有影响,而对样地尺度外推到海拔带尺度的影响则有较复杂的情况.对于对气候变化不敏感的树种以及非地带性树种,空间异质性对样地数据向海拔带尺度外推没有影响;对于大多数对气候变化敏感的地带性树种而言,空间异质性对样地数据向海拔带尺度外推则有影响.