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991.
Bioassay-guided fractionation of two cyanobacterial extracts from Papua New Guinea has yielded hoiamide D in both its carboxylic acid and conjugate base forms. Hoiamide D is a polyketide synthase (PKS)/non-ribosomal peptide synthetase (NRPS)-derived natural product that features two consecutive thiazolines and a thiazole, as well as a modified isoleucine residue. Hoiamide D displayed inhibitory activity against p53/MDM2 interaction (EC(50)=4.5 μM), an attractive target for anticancer drug development.  相似文献   
992.
The aim of this study was to determine whether the Glutathione S-transferase M1 (GSTM1) and P1 (GSTP1) polymorphisms confer susceptibility to rheumatoid arthritis (RA). Meta-analysis was performed on the associations between the GSTM1 and GSTP1 null genotypes and RA, and on the association between smoking or seropositive status and the GSTM1 null genotype in RA patients. Twelve studies involving 3,990 RA patients and 2,815 controls were included in the meta-analysis. All 12 studies examined the GSTM1 polymorphism and three the GSTP1 polymorphism. Meta-analysis of GSTM1 null polymorphism in 2,291 RA and 2,713 control subjects revealed no association between RA and the GSTM1 null genotype (OR?=?1.139, 95?% CI?=?0.914–1.419, p?=?0.246). Stratification by ethnicity indicated no association between the GSTM1 null genotype and RA in Asians or Europeans (OR?=?1.245, 95?% CI?=?0.729–2.124, p?=?0.422; OR?=?1.023, 95?% CI?=?0.794–1.318, p?=?0.863). Furthermore, there was no association between smoking and the GSTM1 null genotype (OR?=?0.943, 95?% CI?=?0.734–1.210, p?=?0.642). In addition, no association was found between seropositive status including anti-CCP (anti-citrullinated antibody) and/or RF (rheumatoid factor) and the GSTM1 null genotype. Meta-analysis of 915 RA and 1,082 controls revealed no association between RA and the GSTP1 null genotype (OR?=?0.965, 95?% CI?=?0.802–1.161, p?=?0.704). Furthermore, stratification by ethnicity indicated no association between the GSTP1 null genotype and RA in Europeans (OR?=?0.794, 95?% CI?=?0.594–1.061, p?=?0.119). This meta-analysis suggests that the GSTM1 and GSTP1 polymorphisms are not associated with the risk of RA. However, due to the small number of studies included and our inability to perform subgroup analysis by environmental factors, further studies are required to explore the roles played by GSTM1 and GSTP1 polymorphisms in the pathogenesis of RA.  相似文献   
993.
Food Biophysics - Caffeic acid phenethyl ester (CAPE) has high cytotoxicity against various cancer cells but has low water solubility and poor bioavailability. The objective of this work was to...  相似文献   
994.
Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed...  相似文献   
995.
Coccidae is one of the major families of scale insects, with many species considered to be serious agricultural or horticultural pests. However, the phylogenetic relationships among coccid subfamilies, tribes and genera are poorly understood because existing hypotheses are based on morphological characters and cladistic analyses. Here, we present the first molecular phylogeny of the family Coccidae based on DNA fragments of a mitochondrial gene (COI), nuclear ribosomal RNA genes (18S and 28S), and elongation factor-1α (EF-1α). We found that some genera (Coccus Linnaeus and Pulvinaria Targioni Tozzetti), tribes (Coccini, Paralecaniini, Pulvinariini and Saissetiini) and subfamilies (Coccinae and Filippiinae) within the family are nonmonophyletic. Formation of a waxy ovisac and the distribution and structures of ventral tubular ducts have been used to define the tribe Pulvinariini morphologically; however, these were found to be homoplastic traits based on ancestral state reconstruction. Accordingly, we propose a new classification of certain groups as follows: (i) the Paralecaniini is raised to subfamily rank, Paralecaniinae stat.n. , except that Neosaissetia Tao, Wong & Chang is retained as a member of Coccinae; (ii) Megapulvinaria Yang and Pulvinarisca Borchsenius are transferred from Coccinae to Pulvinariscinae stat.n. ; and (iii) Metaceronema Takahashi is transferred from Filippiinae to Pulvinariscinae stat.n. We provide amended diagnoses for the newly proposed subfamilies.  相似文献   
996.
Recent studies have highlighted that early enhancement of the glycolytic pathway is a mode of maintaining the pro-inflammatory status of immune cells. Thiamine, a well-known co-activator of pyruvate dehydrogenase complex, a gatekeeping enzyme, shifts energy utilization of glucose from glycolysis to oxidative phosphorylation. Thus, we hypothesized that thiamine may modulate inflammation by alleviating metabolic shifts during immune cell activation. First, using allithiamine, which showed the most potent anti-inflammatory capacity among thiamine derivatives, we confirmed the inhibitory effects of allithiamine on the lipopolysaccharide (LPS)-induced pro-inflammatory cytokine production and maturation process in dendritic cells. We applied the LPS-induced sepsis model to examine whether allithiamine has a protective role in hyper-inflammatory status. We observed that allithiamine attenuated tissue damage and organ dysfunction during endotoxemia, even when the treatment was given after the early cytokine release. We assessed the changes in glucose metabolites during LPS-induced dendritic cell activation and found that allithiamine significantly inhibited glucose-driven citrate accumulation. We then examined the clinical implication of regulating metabolites during sepsis by performing a tail bleeding assay upon allithiamine treatment, which expands its capacity to hamper the coagulation process. Finally, we confirmed that the role of allithiamine in metabolic regulation is critical in exerting anti-inflammatory action by demonstrating its inhibitory effect upon mitochondrial citrate transporter activity. In conclusion, thiamine could be used as an alternative approach for controlling the immune response in patients with sepsis.  相似文献   
997.
998.
Conditions were evaluated for optimum cryopreservation of primary chicken embryo kidney (CEK) cells. The recovery of viable CEK cells was best (50.8% viability) when the concentration of dimethyl sulfoxide (DMSO) in the freezing medium was 20% (v/v). The viability of primary CEK cells was not influenced by the concentration of calf serum in the freezing medium, the duration of storage at −70°C before storage in liquid nitrogen, cell concentration, or the method of addition or dilution of DMSO. Thawed cells recovered and grew in complete growth medium similarly to cells freshly isolated from kidney, and influenza viruses produced plaques in the monolayer. The cryopreservation procedures described here may facilitate maintenance of a standard stock of primary CEK cells for laboratories where preparation of primary CEK cells is not an option.  相似文献   
999.
Panax japonicus is one of the important medicinal plants. Here, we established the protocol for plant regeneration of P. japonicus via direct somatic embryogenesis. Somatic embryos were directly obtained from the segments of zygotic embryos on MS medium with 4.4 μM 2,4-D. Thereafter, somatic embryos were produced by repetitive secondary somatic embryogenesis. The secondary somatic embryo formation was enhanced by plasmolyzing pretreatment (1.0 M mannitol for 10 h). Frequency of secondary somatic embryo formation from cotyledon segments was lowered by plasmolyzing pretreatment, but the number of somatic embryos per explants was greatly increased. Plasmolyzing pretreatment resulted in retardation of embryo growth and required subculture to fresh medium for further growth of embryos into cotyledonary stage. Without plasmolyzing pretreatment, cotyledonary embryos were obtained after 8 weeks of culture. All the cotyledonary somatic embryos germinated by 5 μM GA3 treatment, but only 15.3% were germinated on hormone-free medium. After 2 months of culture on 1/2 strength WPM medium, plantlets produced flowers spontaneously. In the anthers of in vitro flowers, microsporogenesis occurred normally with low number of pollen grains.  相似文献   
1000.
The effects of the liquid pig manure (LM) used in organic farming on the natural abundance of 15N and 13C signatures in plant tissues have not been studied. We hypothesized that application of LM will (1) increase δ15N of plant tissues due to the high δ15N of N in LM as compared with soil N or inorganic fertilizer N, and (2) increase δ13C of plant tissues as a result of high salt concentration in LM that decreases stomatal conductance of plants. To test these hypotheses, variations in the δ15N and δ13C of Chinese cabbage (Brassica campestris L.) and chrysanthemum (Chrysanthemum morifolium Ramatuelle) with two different LMs (with δ15N of +15.6 and +18.2‰) applied at two rates (323 and 646 kg N ha-1 for cabbage and 150 and 300 kg N ha-1 for chrysanthemum), or urea (δ15N = -2.7‰) applied at the lower rate above for the respective species, in addition to the control (no N input) were investigated through a 60-day pot experiment. Application of LM significantly increased plant tissue δ15N (range +9.4 to +14.9‰) over the urea (+3.2 to +3.3‰) or control (+6.8 to 7.7‰) treatments regardless of plant species, strongly reflecting the δ15N of the N source. Plant tissue δ13C were not affected by the treatments for cabbage (range −30.8 to −30.2‰) or chrysanthemum (−27.3 to −26.8‰). However, cabbage dry matter production decreased while its δ13C increased with increasing rate of LM application or increasing soil salinity (P < 0.05), suggesting that salinity stress caused by high rate of LM application likely decreased stomatal conductance and limited growth of cabbage. Our study expanded the use of the δ15N technique in N source (organic vs. synthetic fertilizer) identification and suggested that plant tissue δ13C maybe a sensitive indicator of plant response to salinity stress caused by high LM application rates.  相似文献   
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