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91.
Melero M Rubio-Guerri C Crespo JL Arbelo M Vela AI García-Párraga D Sierra E Domínguez L Sánchez-Vizcaíno JM 《Diseases of aquatic organisms》2011,97(2):167-170
An adult female bottlenose dolphin (Tursiops truncatus) stranded alive and subsequently died several minutes later on the Mediterranean coast of Spain on 14 July 2010. Clinical examination revealed foam through the blowhole and rales upon lung auscultation. On venipuncture, the blood was abnormally dense and dark. Hematological and biochemical abnormalities included dehydration, leukocytosis (48 600 leukocytes microl(-1)) characterized by neutrophilia (48 200 neutrophils microl(-1)), and elevated bilirubin (4.38 mg dl(-1)), alanine aminotransferase (382.3 U l(-1)), aspartate aminotransferase (1449.3 U l(-1)), lactate dehydrogenase (1631.3 U l(-1)), and creatine kinase (404.7 U l(-1)). The most relevant findings of the gross examination were rhomboid-shaped skin lesions, stable froth in the trachea, pulmonary congestion, abnormally thick and rough pleura with adhesions, edematous and congestive superficial cervical and tracheobronchial lymph nodes, red-tinged urine, and severe brain congestion. Histopathology of the kidney, lung, skin, and brain revealed multisystemic intravascular bacterial emboli. Samples of skin, brain, and lung were cultured on Columbia blood agar under both aerobic and anaerobic conditions, and pure and heavy bacterial cultures were obtained from skin and brain samples. The microorganism isolated was Gram-positive, catalase-negative, facultatively anaerobic, and rod-shaped. The isolates were identified as Erysipelothrix rhusiopathiae by the API Coryne biochemical system. Based on the gross and microscopic findings, a diagnosis of acute E. rhusiopathiae septicemia was made. To the best of our knowledge, this is the first report of E. rhusiopathiae septicemia in a free-ranging bottlenose dolphin. 相似文献
92.
Arnó M Betancur-Galvis L González MA Sierra J Zaragozá RJ 《Bioorganic & medicinal chemistry》2003,11(14):3171-3177
Based on two lead cytotoxic spongiane diterpenes, a new series of C7-oxygenated derivatives were synthesized and evaluated for their antitumor activity in vitro against the cancer cell lines HeLa and HEp-2. In general, introduction of either hydroxyl or acetoxy groups at C-7 did not improve the resultant cytotoxicity, while the presence of a butyrate ester led to more active compounds (CC(50)=4.0-9.5 microM). 相似文献
93.
Rebecca C Mueller Fabiana S Paula Babur S Mirza Jorge LM Rodrigues Klaus Nüsslein Brendan JM Bohannan 《The ISME journal》2014,8(7):1548-1550
Understanding the interactions among microbial communities, plant communities and soil properties following deforestation could provide insights into the long-term effects of land-use change on ecosystem functions, and may help identify approaches that promote the recovery of degraded sites. We combined high-throughput sequencing of fungal rDNA and molecular barcoding of plant roots to estimate fungal and plant community composition in soil sampled across a chronosequence of deforestation. We found significant effects of land-use change on fungal community composition, which was more closely correlated to plant community composition than to changes in soil properties or geographic distance, providing evidence for strong links between above- and below-ground communities in tropical forests. 相似文献
94.
Carles Gaig Dolores Vilas Jon Infante María Sierra Inés García-Gorostiaga Mariateresa Buongiorno Mario Ezquerra Maria José Martí Francesc Valldeoriola Miquel Aguilar Matilde Calopa Jorge Hernandez-Vara Eduardo Tolosa 《PloS one》2014,9(10)
Background
Idiopathic Parkinson’s disease (IPD) and LRRK2-associated PD (LRRK2-PD) might be expected to differ clinically since the neuropathological substrate of LRRK2-PD is heterogeneous. The range and severity of extra-nigral nonmotor features associated with LRRK2 mutations is also not well-defined.Objective
To evaluate the prevalence and time of onset of nonmotor symptoms (NMS) in LRRK2-PD patients.Methods
The presence of hyposmia and of neuropsychiatric, dysautonomic and sleep disturbances was assessed in 33 LRRK2-G2019S-PD patients by standardized questionnaires and validated scales. Thirty-three IPD patients, matched for age, gender, duration of parkinsonism and disease severity and 33 healthy subjects were also evaluated.Results
University of Pennsylvania Smell Identification Test (UPSIT) scores in LRRK2-G2019S-PD were higher than those in IPD (23.5±6.8 vs 18.4±6.0; p = 0.002), and hyposmia was less frequent in G2019S carriers than in IPD (39.4% vs 75.8%; p = 0.01). UPSIT scores were significantly higher in females than in males in LRRK2-PD patients (26.9±4.7 vs 19.4±6.8; p<0.01). The frequency of sleep and neuropsychiatric disturbances and of dysautonomic symptoms in LRRK2-G2019S-PD was not significantly different from that in IPD. Hyposmia, depression, constipation and excessive daytime sleepiness, were reported to occur before the onset of classical motor symptoms in more than 40% of LRRK2-PD patients in whom these symptoms were present at the time of examination.Conclusion
Neuropsychiatric, dysautonomic and sleep disturbances occur as frequently in patients with LRRK2-G2019S-PD as in IPD but smell loss was less frequent in LRRK2-PD. Like in IPD, disturbances such as hyposmia, depression, constipation and excessive daytime sleepiness may antedate the onset of classical motor symptoms in LRRK2-G2019S-PD. 相似文献95.
Sierra Phillips Megan Lameka Christopher Beaumont Nileshkumar Chaudhari Jared Halstrom James Rush Jones Nicholas A. Andrews Ashish Shah 《The Iowa orthopaedic journal》2022,42(1):207
BackgroundIntra-articular injections are a standard therapy and diagnostic tool for a variety of wrist conditions. Accurate needle placement is crucial for proper therapeutic benefit and prevention of complications. While some studies claim accurate needle placement requires imaging, others conclude that anatomical guidance is sufficient. This study aimed to evaluate the accuracy of intra-articular wrist needle placement with the ulnocarpal approach across differing levels of training using clinical anatomy alone.MethodsFourteen fresh-frozen, above-elbow cadaveric specimens were used. Intra-articular needle placement into the wrist via an ulnocarpal approach was attempted by nine study participants: two interns, two junior-level residents, two senior-level residents, two hand fellows, and one attending hand surgeon. Each injection was performed based on clinical examination and landmarks alone. The number of attempts and total time taken for each injection was recorded.ResultsOverall success rate was 71%, (89 of 126 attempts) and did not vary significantly across levels of training. Average time for needle placement among all participants was 10.9 ± 6.5 seconds. Timing of successful intra-articular needle placement (10.4 ± 5.2 seconds) significantly differed between levels. However, timing did not trend in any direction with more or less training. No significant difference was noted in total attempts or attempts with successful outcomes when comparing level of training.ConclusionThe ulnocarpal approach is a viable option for injection or aspiration of the wrist without image guidance. We were unable to show any relevant trends with timing or number of attempts in comparison to level of training. Level of Evidence: V 相似文献
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98.
Zhan Gao Ana Sierra Zhiyong Zhu Siva Rama Krishna Koganti Ekaterina Subbotina Ankit Maheshwari Mark E. Anderson Leonid V. Zingman Denice M. Hodgson-Zingman 《PloS one》2016,11(3)
The search for new approaches to treatment and prevention of heart failure is a major challenge in medicine. The adenosine triphosphate-sensitive potassium (KATP) channel has been long associated with the ability to preserve myocardial function and viability under stress. High surface expression of membrane KATP channels ensures a rapid energy-sparing reduction in action potential duration (APD) in response to metabolic challenges, while cellular signaling that reduces surface KATP channel expression blunts APD shortening, thus sacrificing energetic efficiency in exchange for greater cellular calcium entry and increased contractile force. In healthy hearts, calcium/calmodulin-dependent protein kinase II (CaMKII) phosphorylates the Kir6.2 KATP channel subunit initiating a cascade responsible for KATP channel endocytosis. Here, activation of CaMKII in a transaortic banding (TAB) model of heart failure is coupled with a 35–40% reduction in surface expression of KATP channels compared to hearts from sham-operated mice. Linkage between KATP channel expression and CaMKII is verified in isolated cardiomyocytes in which activation of CaMKII results in downregulation of KATP channel current. Accordingly, shortening of monophasic APD is slowed in response to hypoxia or heart rate acceleration in failing compared to non-failing hearts, a phenomenon previously shown to result in significant increases in oxygen consumption. Even in the absence of coronary artery disease, failing myocardium can be further injured by ischemia due to a mismatch between metabolic supply and demand. Ischemia-reperfusion injury, following ischemic preconditioning, is diminished in hearts with CaMKII inhibition compared to wild-type hearts and this advantage is largely eliminated when myocardial KATP channel expression is absent, supporting that the myocardial protective benefit of CaMKII inhibition in heart failure may be substantially mediated by KATP channels. Recognition of CaMKII-dependent downregulation of KATP channel expression as a mechanism for vulnerability to injury in failing hearts points to strategies targeting this interaction for potential preventives or treatments. 相似文献
99.
Expression,Functionality, and Localization of Apurinic/Apyrimidinic Endonucleases in Replicative and Non‐Replicative Forms of Trypanosoma cruzi 下载免费PDF全文
100.
Studies on the activation of the heme-stabilized translational inhibitor of reticulocyte lysates by oxidized glutathione and NADPH depletion 总被引:5,自引:0,他引:5
The translational inhibition produced by addition of oxidized glutathione (GSSG) to hemin-containing reticulocyte lysates and the accompanying phosphorylation of the alpha subunit of the polypeptide chain initiation factor eIF-2 can be prevented or reversed by NADPH generators, including glucose 6-phosphate, deoxyglucose 6-phosphate, fructose 6-phosphate, NADPH itself, and also by dithiols, e.g., dithiothreitol, but not by reduced glutathione (GSH) or other monothiols, e.g., 2-mercaptoethanol. The same is true of the inhibition caused by addition of glutamate dehydrogenase, alpha-ketoglutarate, and NH4+, which may be entirely due to NADPH depletion via the reaction. 相似文献