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81.
Miriam Sanz Ana Paula Dini Andreote Marli Fatima Fiore Felipe Augusto D?rr Ernani Pinto 《Marine drugs》2015,13(6):3892-3919
Cyanobacteria from underexplored and extreme habitats are attracting increasing attention in the search for new bioactive substances. However, cyanobacterial communities from tropical and subtropical regions are still largely unknown, especially with respect to metabolite production. Among the structurally diverse secondary metabolites produced by these organisms, peptides are by far the most frequently described structures. In this work, liquid chromatography/electrospray ionization coupled to high resolution quadrupole time-of-flight tandem mass spectrometry with positive ion detection was applied to study the peptide profile of a group of cyanobacteria isolated from the Southeastern Brazilian coastal forest. A total of 38 peptides belonging to three different families (anabaenopeptins, aeruginosins, and cyanopeptolins) were detected in the extracts. Of the 38 peptides, 37 were detected here for the first time. New structural features were proposed based on mass accuracy data and isotopic patterns derived from full scan and MS/MS spectra. Interestingly, of the 40 surveyed strains only nine were confirmed to be peptide producers; all of these strains belonged to the order Nostocales (three Nostoc sp., two Desmonostoc sp. and four Brasilonema sp.). 相似文献
82.
Crackower MA Kolas NK Noguchi J Sarao R Kikuchi K Kaneko H Kobayashi E Kawai Y Kozieradzki I Landers R Mo R Hui CC Nieves E Cohen PE Osborne LR Wada T Kunieda T Moens PB Penninger JM 《Science (New York, N.Y.)》2003,300(5623):1291-1295
Meiosis is a critical stage of gametogenesis in which alignment and synapsis of chromosomal pairs occur, allowing for the recombination of maternal and paternal genomes. Here we show that FK506 binding protein (Fkbp6) localizes to meiotic chromosome cores and regions of homologous chromosome synapsis. Targeted inactivation of Fkbp6 in mice results in aspermic males and the absence of normal pachytene spermatocytes. Moreover, we identified the deletion of Fkbp6 exon 8 as the causative mutation in spontaneously male sterile as/as mutant rats. Loss of Fkbp6 results in abnormal pairing and misalignments between homologous chromosomes, nonhomologous partner switches, and autosynapsis of X chromosome cores in meiotic spermatocytes. Fertility and meiosis are normal in Fkbp6 mutant females. Thus, Fkbp6 is a component of the synaptonemal complex essential for sex-specific fertility and for the fidelity of homologous chromosome pairing in meiosis. 相似文献
83.
84.
Evaluation of a decision support strategy for the control of powdery mildew,Erysiphe necator (Schw.) Burr., in grapevine in the central region of Chile 下载免费PDF全文
85.
Hayashi AM Matera JM Fonseca Pinto AC 《Journal of the American Veterinary Medical Association》2007,231(6):913-918
OBJECTIVE: To evaluate use of electroacupuncture combined with standard Western medical treatment versus Western medical treatment alone for treatment of thoracolumbar intervertebral disk disease in dogs. DESIGN: Prospective controlled study. ANIMALS: 50 dogs with signs of thoracolumbar intervertebral disk disease. PROCEDURES: Dogs were randomly allocated to 1 of 2 treatment groups and classified as having grade 1 to 5 neurologic dysfunction. Dogs in group 1 received electroacupuncture stimulation combined with standard Western medical treatment; those in group 2 received only standard Western medical treatment. A numeric score for neurologic function was evaluated at 4 time points to evaluate effects of treatments. RESULTS: Time (mean +/- SD) to recover ambulation in dogs with grade 3 and 4 dysfunction in group 1 (10.10 +/- 6.49 days) was significantly lower than in group 2 (20.83 +/- 11.99 days). Success (able to walk without assistance) rate for dogs with grade 3 and 4 dysfunction in group 1 (10/10 dogs) was significantly higher than that of similarly affected dogs in group 2 (6/9 dogs). Dogs without deep pain perception (grade 5 dysfunction) had a success (recovery of pain sensation) rate of 3 of 6 and 1 of 8 in groups 1 and 2, respectively, but the difference was not significant. Overall success rate (all dysfunction grades) for group 1 (23/26; 88.5%) was significantly higher than for group 2 (14/24; 58.3%). CONCLUSIONS AND CLINICAL RELEVANCE: Electroacupuncture combined with standard Western medical treatment was effective and resulted in shorter time to recover ambulation and deep pain perception than did use of Western treatment alone in dogs with signs of thoracolumbar intervertebral disk disease. 相似文献
86.
Figueiredo JP Cruz ML Mendes GM Marucio RL Riccó CH Campagnol D 《Veterinary anaesthesia and analgesia》2008,35(6):511-518
ObjectiveTo assess the brachial plexus block in chickens by an axillary approach and using a peripheral nerve stimulator.Study designProspective, randomized, double-blinded study.AnimalsSix, 84-week old, female chickens.MethodsMidazolam (1 mg kg−1) and butorphanol (1 mg kg−1) were administered into the pectoralis muscle. Fifteen minutes later, the birds were positioned in lateral recumbency and following palpation of the anatomic landmarks, a catheter was inserted using an axillary approach to the brachial plexus. Lidocaine or bupivacaine (1 mL kg−1) was injected after plexus localization by the nerve stimulator. Sensory function was tested before and after blockade (carpus, radius/ulna, humerus and pectoralis muscle) in the blocked and unblocked wings. The latency to onset of motor and sensory block and the duration of sensory block were recorded. A Friedman nonparametric one-way repeated-measures anova was used to compare scores from baseline values over time and to compare the differences between wings at each time point.ResultsA total of 18 blocks were performed with a success rate of 66.6% (12/18). The latency for motor block was 2.8 ± 1.1 and 3.2 ± 0.4 minutes for lidocaine and bupivacaine, respectively. The latencies for and durations of the sensory block were 6.0 ± 2.5 and 64.0 ± 18.0 and 7.8 ± 5.8 and 91.6 ± 61.7 minutes for lidocaine and bupivacaine, respectively. There was no statistical difference between these times for lidocaine or bupivacaine. Sensory function was not abolished in nonblocked wings.Conclusions and clinical relevanceThe brachial plexus block was an easy technique to perform but had a high failure rate. It might be useful for providing anesthesia or postoperative analgesia of the wing in chickens and exotic avian species that have similar wing anatomy. 相似文献
87.
Daphne W. Goldberg Miriam R. Fernandes Fbio P. Sellera Daniela G. C. Costa Ana Paula Loureiro Bracarense Nilton Lincopan 《Zoonoses and public health》2019,66(5):540-545
CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal. 相似文献
88.
Marie Verkola Eeva Pietola Asko Jrvinen Kristian Lindqvist Paula M. Kinnunen Annamari Heikinheimo 《Zoonoses and public health》2019,66(6):667-678
The occurrence of multidrug‐resistant zoonotic bacteria in animals has been increasing worldwide. Working in close contact with livestock increases the risk of carriage of these bacteria. We investigated the occurrence of extended‐spectrum beta‐lactamase (ESBL) and plasmidic AmpC beta‐lactamase producing Enterobacteriaceae (ESBL/pAmpC‐PE) and livestock‐associated methicillin‐resistant Staphylococcus aureus (LA‐MRSA) in Finnish veterinarians (n = 320). In addition to microbiological samples, background information was collected. Bacterial whole genome sequencing was performed to deduce sequence types (STs), spa types and resistance genes of the isolates. In total, 3.0% (9/297) of the veterinarians carried ESBL producing Escherichia coli, with one ESBL producing E. coli isolate producing also AmpC. Seven different STs, sequences of several different plasmid groups as well as several different blaESBL/pAmpC genes existed in different combinations. No carbapenemase or colistin resistance genes were detected. MRSA was detected in 0.3% (1/320) of the samples. The strain belonged to LA‐MRSA clonal complex (CC) 398 (ST398, spa type 011, lacking Panton‐Valentine leukocidin genes). In conclusion, this study shows low carriage of multidrug‐resistant zoonotic bacteria in Finnish veterinarians. However, finding LA‐MRSA for the first time in a sample from a veterinarian in a country with prudent use of animal antimicrobials and regarding the recent rise of LA‐MRSA on Finnish pig farms, a strong recommendation to protect people working in close contact with animals carrying LA‐MRSA CC398 is given. Further studies are needed to explain why the prevalence of LA‐MRSA in veterinarians is lower in Finland than in other European countries. 相似文献
89.
Fedoriw AM Stein P Svoboda P Schultz RM Bartolomei MS 《Science (New York, N.Y.)》2004,303(5655):238-240
The imprinted regulation of H19 and Insulin-like growth factor 2 expression involves binding of the vertebrate insulator protein, CCCTC binding factor (CTCF), to the maternally hypomethylated differentially methylated domain (DMD). How this hypomethylated state is maintained during oogenesis and the role of CTCF, if any, in this process are not understood. With the use of a transgenic RNA interference (RNAi)-based approach to generate oocytes with reduced amounts of CTCF protein, we found increased methylation of the H19 DMD and decreased developmental competence of CTCF-deficient oocytes. Our results suggest that CTCF protects the H19 DMD from de novo methylation during oocyte growth and is required for normal preimplantation development. 相似文献
90.
Leonardo Manir Feitosa Lucas Pereira Martins Leandro Augusto de Souza Junior Rosangela Paula Lessa 《水产资源保护:海洋与淡水生态系统》2020,30(5):882-891
- Updated distribution ranges are crucial for conservation status assessments. Comprehensive analyses combining published literature and available data on historical catches and species distribution models (SDMs) are effective tools that could improve the prediction of more realistic scenarios for some species, especially those with limited information available and facing multiple threats.
- The present study aimed at generating an updated distribution for the smalltail shark Carcharhinus porosus, one of the most threatened and understudied shark species of the western Atlantic Ocean. Estimates of the key areas for this species conservation based on the SDMs, and trends in catch probabilities throughout its distribution range are provided.
- Four algorithms (BIOCLIM, Domain, Mahalanobis, and Maximum Entropy) were used to model the distribution of C. porosus and calculate its habitat suitability based on marine environmental variables. To assess historical catch probability trends, we built a generalized linear model from published and grey literature data. This analysis was used to estimate catch probability as an indication of population trends.
- SDMs suggest that the northern coast of South America (NCSA) harbours the most suitable habitats for C. porosus in the world, which was expected given its historically high catch rate in this region. In addition, there was a continuously declining catch probability trend starting in the 1970s. However, the decline was smaller for the NCSA as compared with the Gulf of Mexico and the eastern South America coast.
- Results indicate that the NCSA should be considered the currently most important area in the world for this species conservation. Furthermore, the lack of data throughout Central and South American marine regions hampers the evaluation of extinction risk throughout its updated distribution. Thus, research in these areas is urgently required for a more comprehensive conservation status assessment.