[Effect of Baihu Guizhi decoction on characteristic methylation genes expression of pyretic arthralgia rat model].

To investigate the characteristic methylation genes of pyretic arthralgia model in hot and dampness environment and the regulation effect of Baihu Guizhi decoction on this characteristic methylation genes. Plantar injection of CFA was used in hot and dampness environment to induce the pyretic arthralgia rat models. From 15th day after modeling, Baihu Guizhi decoction was given for 30 days. Foot volume was detected every 4 days after modeling, and HE staining was used to detect the histopathology of all rats' ankle joint at day 45.MeDIP-Seq sequencing method was used to detect the methylation level of knee joint synovial, and the method of difference sets was used to screen the characteristic methylation genesinpyretic arthralgia models.The contents of IL-1ß, IL-17, TNF-α, EGF, IL-12p70, IL-4, IL-6 and IFN-γ in serum were measured by using suspension chips. The mRNA expression level of characteristic methylation genes was measured by qRT-PCR. The results suggested that as compared with adjuvant arthritis rat models(AA), the foot swelling and histopathology inpyretic arthralgia models (PA) were only slightly increased. As compared with normal group (NG), the wholegenome CpG island in both AA and PA groups was kept in a lower methylation state, furthermore, the methylation level was lowest in PA group; with 705 difference methylation genes in AA group and 2 418 difference methylation genes in PA group. As compared with AA, there were 1 287 difference methylation genes, including 974 down-regulated methylation genesand 313 up-regulated methylation genes. This difference methylation genes were mostly enriched in 32 KEGG pathways. Moreover, there were 52 characteristic methylation genes of PA models in promoter region, including 36 down-regulatedmethylation genes and 16 up-regulatedmethylation genes. After drug intervention, Baihu Guizhi decoction improved the foot swelling and pathological injury in PA models, significantly decreased the levels of IL-1ß, TNF-α, EGF, VEGF, IL-17, IL-12p70, inhibited the mRNA expression levels of down-regulated methylation genes AHCY and RPL3, and promoted the mRNA expression levels of up-regulated methylation gene Agxt. In conclusion, unique methylation changes of synovial genes were present in PA models, and Baihu Guizhi decoction may adjust the methylation level of PA's characteristic methylation genes to achieve the therapeutic effect of pyretic arthralgia.

Linezolid update: stable in vitro activity following more than a decade of clinical use and summary of associated resistance mechanisms.

Linezolid, approved for clinical use since 2000, has become an important addition to the anti-Gram-positive infection armamentarium. This oxazolidinone drug has in vitro and in vivo activity against essentially all Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The in vitro activity of linezolid was well documented prior to its clinical application, and several ongoing surveillance studies demonstrated consistent and potent results during the subsequent years of clinical use. Emergence of resistance has been limited and associated with invasive procedures, deep organ involvement, presence of foreign material and mainly prolonged therapy. Non-susceptible organisms usually demonstrate alterations in the 23S rRNA target, which remain the main resistance mechanism observed in enterococci; although a few reports have described the detection of cfr-mediated resistance in Enterococcus faecalis. S. aureus isolates non-susceptible to linezolid remain rare in large surveillance studies. Most isolates harbour 23S rRNA mutations; however, cfr-carrying MRSA isolates have been observed in the United States and elsewhere. It is still uncertain whether the occurrences of such isolates are becoming more prevalent. Coagulase-negative isolates (CoNS) resistant to linezolid were uncommon following clinical approval. Surveillance data have indicated that CoNS isolates, mainly Staphylococcus epidermidis, currently account for the majority of Gram-positive organisms displaying elevated MIC results to linezolid. In addition, these isolates frequently demonstrate complex and numerous resistance mechanisms, such as alterations in the ribosomal proteins L3 and/or L4 and/or presence of cfr and/or modifications in 23S rRNA. The knowledge acquired during the past decades on this initially used oxazolidinone has been utilized for developing new candidate agents, such as tedizolid and radezolid, and as linezolid patents soon begin to expire, generic brands will certainly become available. These events will likely establish a new chapter for this successful class of antimicrobial agents.

Ribosomal protein L3 mediated the transport of digoxin in Xenopus laevis oocyte.

Ribosomal protein L3 (RPL3) is known to be an indispensable and essential component for the peptidyltransferase center. In the present study, we found a novel function of RPL3 using a Xenopus laevis oocyte expression system. When expressed in X. oocytes, RPL3 mediated the high affinity transport of [(3)H]digoxin (K(m) = 213.3 ± 46.8 nM) in a time-, concentration-, and sodium-dependent manners. The maximum velocity of the transport of [(3)H]digoxin via RPL3 produced at physiological pH. However, we did not observe RPL3-mediated transport of several organic solutes such as [(14)C]androstenedione, [(3)H]dexamethasone, [(3)H]dehydroepiandrosterone sulfate, [(3)H]L-tryptophan, [(14)C]L-ascorbic acid, [(14)C]α-ketoglutarate, [(14)C]glutarate, [(3)H]methotrexate, [(3)H]bumetanide, [(3)H]probenecid, [(14)C]salicylic acid, [(14)C]theophylline and [(3)H]valproate. Our results suggest that RPL3 functions as a drug carrier protein and may be involved in the digoxin toxicity in the human body.

Evaluation of hypothalamic gene expression in mice divergently selected for heat loss.

Mouse lines divergently selected for heat loss were evaluated for correlated responses in the hypothalamic transcriptome. High (MH) heat loss mice have approximately 50% greater heat loss, approximately 35% less body fat, approximately 20% greater feed intake, approximately 100% greater locomotor activity levels, and higher core body temperature compared with low (ML) heat loss mice. We evaluated hypothalamic expression between inbred lines derived from MH and ML lines (IH and IL, respectively) using cDNA microarrays and selected genes previously isolated in a large differential-display PCR experiment. Northern analysis was used to confirm differences, revealing higher hypothalamic mRNA expression of oxytocin (Oxt) and tissue inhibitor of metalloproteinase 2 (Timp-2) in the IH line. Real-time PCR assays were developed for Oxt, Timp-2, and ribosomal protein L3 (Rpl3, previously found to be upregulated in IL) and confirmed differential expression of these genes with potential physiological relevance in energy balance. These results provide information on correlated responses in the transcriptome of mice selected for high and low energy expenditure and reveal new information regarding genetic regulation of energy balance.

Gene expression in hypothalamus and brown adipose tissue of mice divergently selected for heat loss.

Gene expression was evaluated in mice divergently selected for 16 generations for heat loss, measured by direct calorimetry. The high (MH) heat loss line has approximately 50% greater heat loss, approximately 35% less body fat, approximately 20% greater feed intake, and twofold greater activity levels than the low (ML) heat loss line. At 11 wk, inbred males (developed from MH and ML) were euthanized 3 h after dark for dissection of tissues and extraction of RNA. Differential display PCR (DD-PCR) was used to evaluate transcriptional differences between lines in hypothalamus and brown adipose tissue (BAT). Evaluation was replicated within and across lines, using family pools of mRNA. Two genes were confirmed by competitive RT-PCR and/or Northern analysis to have greater levels of mRNA present in ML relative to MH mice. In both hypothalamus and BAT, the ribosomal protein L3 (RPL3) gene was expressed at higher levels in ML, whereas an unknown expressed sequence tag (EST) was also found at higher levels in the hypothalamus of ML mice. These results implicate RPL3 in regulation of energy balance and extend the genetic dissection of response to selection to the transcriptional level.