984 resultados para cyclic imido double bond
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Three isosporan species are described from the double-collared seedeater, Sporophila caerulescens from Eastern Brazil. Isospora sporophilae n. sp. oocysts spherical to subspherical; oocyst wall bi-layered, smooth, inner layer colorless to pale yellowish, 21.6 × 20.9 (19.20-23.20 × 18.40-22.60) µm, shape-index 1.03 ± 0.02 (1-1.10), with no micropyle or oocyst residuum. Polar bodies splinter-like or comma-like. Sporocysts ovoidal, 15.2 × 10.6 (17.40-12.80 × 12.60-8.40) µm, shape-index 1.43 ± 0.14 (1.17-1.81), with knob-like Stieda body and residuum. Large crystalloid body in the center of the sporocyst. Isospora flausinoi n. sp. oocysts spherical to subspherical, oocyst wall bi-layered, smooth, colorless, 17.30 x 16.53 (14-20 × 13.60-20) µm, shape-index 1.05 ± 0.04 (1-1.21). Micropyle and oocyst residuum absent; presence of a large polar body. Sporocyst piriform, 14.88 x 10.70 (11.80-18 × 8-12.40) µm, shape-index 1.40 ± 0.18 (1.07-1.77), with smooth, thin, single-layered wall. Sporocyst with rounded Stieda body with no substieda body, and residuum composed of granular material. Isospora teixeirafilhoi n. sp. oocysts spherical to subspherical, oocyst wall bi-layered, smooth, colorless, 17.41 x 16.81 (15.60 19.40 × 14.20-18.80) µm. Shape-index 1.04 ± 0.08 (1-1.12). Micropyle and oocyst residuum absent; presence of a small double-lobuled polar body. Sporocyst ovoid, 11.74 × 8.12 (9-14.20 × 6.20-9.40) µm. Shape-index 1.46 ± 0.23 (1.06-1.88). Sporocyst with knob-like Stieda body, no sub-Stieda body and residuum composed of granular material.
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Typically at dawn on a hot summer day, land plants need precise molecular thermometers to sense harmless increments in the ambient temperature to induce a timely heat shock response (HSR) and accumulate protective heat shock proteins in anticipation of harmful temperatures at mid-day. Here, we found that the cyclic nucleotide gated calcium channel (CNGC) CNGCb gene from Physcomitrella patens and its Arabidopsis thaliana ortholog CNGC2, encode a component of cyclic nucleotide gated Ca(2+) channels that act as the primary thermosensors of land plant cells. Disruption of CNGCb or CNGC2 produced a hyper-thermosensitive phenotype, giving rise to an HSR and acquired thermotolerance at significantly milder heat-priming treatments than in wild-type plants. In an aequorin-expressing moss, CNGCb loss-of-function caused a hyper-thermoresponsive Ca(2+) influx and altered Ca(2+) signaling. Patch clamp recordings on moss protoplasts showed the presence of three distinct thermoresponsive Ca(2+) channels in wild-type cells. Deletion of CNGCb led to a total absence of one and increased the open probability of the remaining two thermoresponsive Ca(2+) channels. Thus, CNGC2 and CNGCb are expected to form heteromeric Ca(2+) channels with other related CNGCs. These channels in the plasma membrane respond to increments in the ambient temperature by triggering an optimal HSR, leading to the onset of plant acquired thermotolerance.
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Simple double repetitive element polymerase chain reaction (MaDRE-PCR) and Pvu II-IS1245 restriction fragment length polymorphism (RFLP) typing methods were used to type 41 Mycobacterium avium isolates obtained from 14 Aids inpatients and 10 environment and animals specimens identified among 53 mycobacteria isolated from 237 food, chicken, and pig. All environmental and animals strains showed orphan patterns by both methods. By MaDRE-PCR four patients, with multiple isolates, showed different patterns, suggesting polyclonal infection that was confirmed by RFLP in two of them. This first evaluation of MaDRE-PCR on Brazilian M. avium strains demonstrated that the method seems to be useful as simple and less expensive typing method for screening genetic diversity in M. avium strains on selected epidemiological studies, although with limitation on analysis identical patterns except for one band.
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OBJECTIVE: To evaluate the efficacy and safety of pregabalin monotherapy versus placebo for symptomatic pain relief and improvement of patient global assessment in patients with fibromyalgia (FM) enrolled from countries outside the United States. METHODS: This international, multicenter, double-blind, placebo-controlled trial randomly assigned 747 patients with FM to placebo or 300, 450, or 600 mg/day pregabalin twice daily for 14 weeks. Primary efficacy measures were endpoint mean pain scores and Patient Global Impression of Change (PGIC). Secondary outcomes included assessments of sleep and function. RESULTS: Patients in the 450 mg/day pregabalin group showed significant improvements versus placebo in endpoint mean pain score (-0.56; p = 0.0132), PGIC (73% improved vs 56% placebo; p = 0.0017), and function [Fibromyalgia Impact Questionnaire (FIQ) total score -5.85; p = 0.0012]. PGIC was also significant for 600 mg/day pregabalin (69% improved; p = 0.0227). Results for these endpoints were nonsignificant for pregabalin at 300 mg/day and for pain and FIQ score at 600 mg/day. Early onset of pain relief was seen, with separation from placebo detected by Week 1 in all pregabalin groups. All pregabalin doses demonstrated superiority to placebo on the Medical Outcomes Study-Sleep Scale Sleep Disturbance subscale and the Sleep Quality diary. Dizziness and somnolence were the most frequently reported adverse events. CONCLUSION: Pregabalin demonstrated modest efficacy in pain, global assessment, and function in FM at 450 mg/day, and improved sleep across all dose levels, but it did not provide consistent evidence of benefit at 300 and 600 mg/day in this study. Pregabalin was generally well tolerated for the treatment of FM. (Clinical trial registry NCT00333866).
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Physicians who frequently perform fluoroscopic examinations are exposed to high intensity radiation fields. The exposure monitoring is performed with a regular personal dosimeter under the apron in order to estimate the effective dose. However, large parts of the body are not protected by the apron (e.g. arms, head). Therefore, it is recommended to wear a supplemental dosimeter over the apron to obtain a better representative estimate of the effective dose. The over-apron dosimeter can also be used to estimate the eye lens dose. The goal of this study was to investigate the relevance of double dosimetry in interventional radiology. First the calibration procedure of the dosimeters placed over the apron was tested. Then, results of double dosimetry during the last five years were analyzed. We found that the personal dose equivalent measured over a lead apron was underestimated by ∼20% to ∼40% for X-ray beam qualities used in radiology. Measurements made over five-year period confirm that the use of a single under-apron dosimeter is inadequate for personnel monitoring. Relatively high skin dose (>10 mSv/month) would have remained undetected without a second dosimeter placed on the apron.
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Background Based on several experimental results and on a preliminary study, a trial was undertaken to assess the efficacy of adalimumab, a TNF-α inhibitor, in patients with radicular pain due to lumbar disc herniation. Methods A multicentre, double-blind, randomised controlled trial was conducted between May 2005 and December 2007 in Switzerland. Patients with acute (< 12 weeks) and severe (Oswestry Disability index > 50) radicular leg pain and imaging-confirmed lumbar disc herniation were randomised to receive as adjuvant therapy either two subcutaneous injections of adalimumab (40 mg) at 7 days interval or matching placebo. The primary outcome was leg pain, which was recorded every day for 10 days and at 6-weeks and 6- months based on a visual analogue scale (0 to 100). Results Of the 265 patients screened, 61 were enrolled (adalimumab= 31) and 4 were lost to follow-up. Over time, the evolution of leg pain was more favourable in the adalimumab group than in the placebo group (p<0.001). However, the effect size was relatively small and at last follow-up the difference was 13.8 (CI95% -11.5 - 39.0). In the adalimumab group twice as many patients fulfilled the criteria for "responders" and for "low residual disease impact" ( p<0.05) and fewer surgical discectomies were performed (6 versus 13, p=0.04). Conclusion The addition of a short course of adalimumab to the treatment regimen of patients suffering from acute and severe sciatica resulted in a small decrease in leg pain and in significantly fewer surgical procedures.
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We compared the phosphorylation and internalization properties of constitutively active alpha-1b adrenergic receptor (AR) mutants carrying mutations in two distant receptor domains, i.e., at A293 in the distal part of the third intracellular loop and at D142 of the DRY motif lying at the end of the third transmembrane domain. For the A293E and A293I mutants the levels of agonist-independent phosphorylation were 150% and 50% higher than those of the wild-type alpha-1b AR, respectively. On the other hand, for the constitutively active D142A and D142T mutants, the basal levels of phosphorylation were similar to those of the wild-type alpha-1b AR and did not appear to be further stimulated by epinephrine. Overexpression of the guanyl nucleotide binding regulatory protein-coupled receptor kinase GRK2 further increases the basal phosphorylation of the A293E mutant, but not that of D142A mutant. Both the wild-type alpha-1b AR and the A293E mutant could undergo beta-arrestin-mediated internalization. The epinephrine-induced internalization of the constitutively active A293E mutant was significantly higher than that of the wild-type alpha-1b AR. In contrast, the D142A mutant was impaired in its ability to interact with beta-arrestin and to undergo agonist-induced internalization. Interestingly, a double mutant A293E/D142A retained very high constitutive activity and regulatory properties of both the A293E and D142A receptors. These findings demonstrate that two constitutively activating mutations occurring in distant receptor domains of the alpha-1b AR have divergent effects on the regulatory properties of the receptor.
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The protein sequence deduced from the open reading frame of a human placental cDNA encoding a cAMP-responsive enhancer (CRE)-binding protein (CREB-327) has structural features characteristic of several other transcriptional transactivator proteins including jun, fos, C/EBP, myc, and CRE-BP1. Results of Southwestern analysis of nuclear extracts from several different cell lines show that there are multiple CRE-binding proteins, which vary in size in cell lines derived from different tissues and animal species. To examine the molecular diversity of CREB-327 and related proteins at the nucleic acid level, we used labeled cDNAs from human placenta that encode two different CRE-binding proteins (CREB-327 and CRE-BP1) to probe Northern and Southern blots. Both probes hybridized to multiple fragments on Southern blots of genomic DNA from various species. Alternatively, when a human placental c-jun probe was hybridized to the same blot, a single fragment was detected in most cases, consistent with the intronless nature of the human c-jun gene. The CREB-327 probe hybridized to multiple mRNAs, derived from human placenta, ranging in size from 2-9 kilobases. In contrast, the CRE-BP1 probe identified a single 4-kilobase mRNA. Sequence analyses of several overlapping human genomic cosmid clones containing CREB-327 sequences in conjunction with polymerase chain reaction indicates that the CREB-327/341 cDNAs are composed of at least eight or nine exons, and analyses of human placental cDNAs provide direct evidence for at least one alternatively spliced exon. Analyses of mouse/hamster-human hybridoma DNAs by Southern blotting and polymerase chain reaction localizes the CREB-327/341 gene to human chromosome 2. The results indicate that there is a dichotomy of CREB-like proteins, those that are related by overall structure and DNA-binding specificity as well as those that are related by close similarities of primary sequences.
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The discovery of a targeted therapeutic compound along with its companion predictive biomarker is a major goal of clinical development for a personalized anticancer therapy to date. Here we present evidence of the predictive value of TLR3 expression by tumor cells for the efficacy of Poly (A:U) dsRNA in 194 breast cancer patients enrolled in a randomized clinical trial. Adjuvant treatment with double-stranded RNA (dsRNA) was associated with a significant decrease in the risk of metastatic relapse in TLR3 positive but not in TLR3-negative breast cancers. Moreover, we show the functional relevance of TLR3 expression by human tumor cells for the antitumor effects mediated by dsRNA in several preclinical mouse models carried out in immunocompromised animals. These 2 independent lines of evidence relied upon the generation of a novel tool, an anti-TLR3 antibody (40F9.6) validated for routine detection of TLR3 expression on paraffin-embedded tissues. Altogether, these data suggest that dsRNA mediates its therapeutic effect through TLR3 expressed on tumor cells, and could therefore represent an effective targeted treatment in patients with TLR3-positive cancers.
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Leptin, a 16-kDa protein mainly produced by adipose tissue, has been involved in the control of energy balance through its hypothalamic receptor. However, pleiotropic effects of leptin have been identified in reproduction and pregnancy, particularly in placenta, where it was found to be expressed. In the current study, we examined the effect of cAMP in the regulation of leptin expression in trophoblastic cells. We found that dibutyryl cAMP [(Bu)(2)cAMP], a cAMP analog, showed an inducing effect on endogenous leptin expression in BeWo and JEG-3 cell lines when analyzed by Western blot analysis and quantitative RT-PCR. Maximal effect was achieved at 100 microM. Leptin promoter activity was also stimulated, evaluated by transient transfection with a reporter plasmid construction. Similar results were obtained with human term placental explants, thus indicating physiological relevance. Because cAMP usually exerts its actions through activation of protein kinase A (PKA) signaling, this pathway was analyzed. We found that cAMP response element-binding protein (CREB) phosphorylation was significantly increased with (Bu)(2)cAMP treatment. Furthermore, cotransfection with the catalytic subunit of PKA and/or the transcription factor CREB caused a significant stimulation on leptin promoter activity. On the other hand, the cotransfection with a dominant negative mutant of the regulatory subunit of PKA inhibited leptin promoter activity. We determined that cAMP effect could be blocked by pharmacologic inhibition of PKA or adenylyl ciclase in BeWo cells and in human placental explants. Thereafter, we decided to investigate the involvement of the MAPK/ERK signaling pathway in the cAMP effect on leptin induction. We found that 50 microm PD98059, a MAPK kinase inhibitor, partially blocked leptin induction by cAMP, measured both by Western blot analysis and reporter transient transfection assay. Moreover, ERK 1/2 phosphorylation was significantly increased with (Bu)(2)cAMP treatment, and this effect was dose dependent. Finally, we observed that 50 microm PD98059 inhibited cAMP-dependent phosphorylation of CREB in placental explants. In summary, we provide some evidence suggesting that cAMP induces leptin expression in placental cells and that this effect seems to be mediated by a cross talk between PKA and MAPK signaling pathways.