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961.
Margaret A.L. Blackie Vanessa Yardley Kelly Chibale 《Bioorganic & medicinal chemistry letters》2010,20(3):1078-1080
Synthesis of the potent antiplasmodial 4-aminoquinoline, phenylequine (PQ), is reported for the first time. PQ and the two analogues show increased efficacy in moving from the chloroquine sensitive D10 to the chloroquine resistant K1 strain in vitro. The in vivo efficacy of PQ, and salts thereof, have been determined in Plasmodium berghei ANKA and Plasmodium yoelii. Phenylequine hydrochloride has shown an ED50 of 0.81 in P. yoelii (cf chloroquine ED50 = 1.31). 相似文献
962.
963.
Geraldo de Nardi Júnior Margareth Elide Genovez Marcio Garcia Ribeiro Vanessa Castro André Mendes Jorge 《Biologicals》2010,38(4):474-478
Leptospira spp. serovars Hardjo and Wollfi from Sejroe serogroup have been detected in livestock in Brazil, where the main control procedures rely on vaccination. The potency of two commercial vaccines available in this country was monitored by microagglutination test-MAT and in vitro growth inhibition test-GIT in serum samples from 33 female buffaloes divided into: G1-unvaccinated control; G2-vaccinated with Leptobac-6® containing serovars Hardjo and Wolffi and G3-vaccinated with Triangle-9® containing serovar Hardjo. G2 and G3 animals were vaccinated on day zero, and received a booster and two revaccinations on days 30, 210 and 390 and G1 animals received phosphate buffered saline. Serum samples were collected at 15-day intervals between days 0 and 60; and at 30-day intervals between days 60 and 540 and were tested by MAT and GIT with serovars Hardjo and Wolffi. G1 remained negative throughout the experiment. Both vaccines were able to induce agglutinating and growth inhibition antibodies. Six months after the last revaccination, all animals tested negative by MAT, but still were positive by GIT until the end of experimental period. GIT could be a good tool to evaluate the potency and to monitor antibodies responses of vaccines of Sejroe group serovars. 相似文献
964.
Simone Simionatto Silvana B. Marchioro Vanessa Galli Daiane D. Hartwig Rodrigo M. Carlessi Fernanda M. Munari Jomar P. Laurino Fabricio R. Conceição Odir A. Dellagostin 《Protein expression and purification》2010,69(2):132-136
Mycoplasma hyopneumoniae, the etiological agent of swine enzootic pneumonia, is an important pathogen in the swine industry worldwide. Vaccination is the most cost-effective strategy for controlling and prevention of this disease. However, investigations on pathogenicity mechanisms as well as current serological detection methods and the development of new recombinant subunit vaccines are hampered by the lack of known and well characterized species-specific M. hyopneumoniae antigens. In this work, 54 predicted genes encoding proteins with potential to be used as subunit vaccine or antigens in diagnostic tests were selected, amplified by PCR and cloned into Escherichia coli expression vectors. Recombinant protein expression, solubility and yields were analyzed. The majority of the recombinant proteins were expressed in inclusion bodies. After solubilization with urea or N-lauroyl sarcosine, recombinant proteins were purified by Ni2+ affinity chromatography. This approach allowed purification of thirty recombinant M. hyopneumoniae proteins which will be evaluated as vaccine candidates and/or as antigens to be used in diagnostic tests. 相似文献
965.
Shepherd R Singer Michal Amit-Kohn Samuel Weiss Jonathan Rosenblum Guy Maoz Noah Samuels Esther Lukasiewicz Laurence Freedman Ora Paltiel Menachem Itzchaki Meir Niska Menachem Oberbaum 《BMC clinical pharmacology》2010,10(1):1-8
Background
In spite of recent advances in post-operative pain relief, pain following orthopedic surgery remains an ongoing challenge for clinicians. We examined whether a well known and frequently prescribed homeopathic preparation could mitigate post-operative pain.Method
We performed a randomized, double blind, placebo-controlled trial to evaluate the efficacy of the homeopathic preparation Traumeel S® in minimizing post-operative pain and analgesic consumption following surgical correction of hallux valgus. Eighty consecutive patients were randomized to receive either Traumeel tablets or an indistinguishable placebo, and took primary and rescue oral analgesics as needed. Maximum numerical pain scores at rest and consumption of oral analgesics were recorded on day of surgery and for 13 days following surgery.Results
Traumeel was not found superior to placebo in minimizing pain or analgesic consumption over the 14 days of the trial, however a transient reduction in the daily maximum post-operative pain score favoring the Traumeel arm was observed on the day of surgery, a finding supported by a treatment-time interaction test (p = 0.04).Conclusions
Traumeel was not superior to placebo in minimizing pain or analgesic consumption over the 14 days of the trial. A transient reduction in the daily maximum post-operative pain score on the day of surgery is of questionable clinical importance.Trial Registration
This study was registered at ClinicalTrials.gov. # NCT00279513 相似文献966.
Knowledge of dinoflagellate diversity in Brazilian reservoirs is limited, especially in subtropical environments. We investigated as to how nutrients and other environmental variables influenced the biomass of Dinophyceae species in three subtropical ecosystems. The reservoirs Samuara, Faxinal, and São Miguel were sampled fortnightly from 2002 to 2006, and eight dinoflagellate taxa were identified. High temperature was a determining factor for the occurrence of Peridinium africanum Lemmermann. Peridinium umbonatum Stein and P. willei Huitfeld-Kass required high concentrations of nutrients. P. willei was inversely related to temperature and directly related to nutrients. P. umbonatum Stein var. umbonatum Stein showed the largest range of tolerance toward resources. Durinskia baltica Carty &; Cox and Peridinium gatunense Nygaard could be opportunistic, since they did not show any spatial or temporal pattern. 相似文献
967.
968.
Hubbard VM Valdor R Patel B Singh R Cuervo AM Macian F 《Journal of immunology (Baltimore, Md. : 1950)》2010,185(12):7349-7357
Macroautophagy is a highly conserved mechanism of lysosomal-mediated protein degradation that plays a key role in maintaining cellular homeostasis by recycling amino acids, reducing the amount of damaged proteins, and regulating protein levels in response to extracellular signals. We have found that macroautophagy is induced after effector T cell activation. Engagement of the TCR and CD28 results in enhanced microtubule-associated protein 1 light chain 3 (LC3) processing, increased numbers of LC3-containing vesicles, and increased LC3 flux, indicating active autophagosome formation and clearance. The autophagosomes formed in stimulated T cells actively fuse with lysosomes to degrade their cargo. Using a conditional KO mouse model where Atg7, a critical gene for macroautophagy, is specifically deleted in T cells, we have found that macroautophagy-deficient effector Th cells have defective IL-2 and IFN-γ production and reduced proliferation after stimulation, with no significant increase in apoptosis. We have found that ATP generation is decreased when autophagy is blocked, and defects in activation-induced cytokine production are restored when an exogenous energy source is added to macroautophagy-deficient T cells. Furthermore, we present evidence showing that the nature of the cargo inside autophagic vesicles found in resting T cells differs from the cargo of autophagosomes in activated T cells, where mitochondria and other organelles are selectively excluded. These results suggest that macroautophagy is an actively regulated process in T cells that can be induced in response to TCR engagement to accommodate the bioenergetic requirements of activated T cells. 相似文献
969.
Jacob D. Estes Levelle D. Harris Nichole R. Klatt Brian Tabb Stefania Pittaluga Mirko Paiardini G. Robin Barclay Jeremy Smedley Rhonda Pung Kenneth M. Oliveira Vanessa M. Hirsch Guido Silvestri Daniel C. Douek Christopher J. Miller Ashley T. Haase Jeffrey Lifson Jason M. Brenchley 《PLoS pathogens》2010,6(8)
The chronic phase of HIV infection is marked by pathological activation of the immune system, the extent of which better predicts disease progression than either plasma viral load or CD4+ T cell count. Recently, translocation of microbial products from the gastrointestinal tract has been proposed as an underlying cause of this immune activation, based on indirect evidence including the detection of microbial products and specific immune responses in the plasma of chronically HIV-infected humans or SIV-infected Asian macaques. We analyzed tissues from SIV-infected rhesus macaques (RMs) to provide direct in situ evidence for translocation of microbial constituents from the lumen of the intestine into the lamina propria and to draining and peripheral lymph nodes and liver, accompanied by local immune responses in affected tissues. In chronically SIV-infected RMs this translocation is associated with breakdown of the integrity of the epithelial barrier of the gastrointestinal (GI) tract and apparent inability of lamina propria macrophages to effectively phagocytose translocated microbial constituents. By contrast, in the chronic phase of SIV infection in sooty mangabeys, we found no evidence of epithelial barrier breakdown, no increased microbial translocation and no pathological immune activation. Because immune activation is characteristic of the chronic phase of progressive HIV/SIV infections, these findings suggest that increased microbial translocation from the GI tract, in excess of capacity to clear the translocated microbial constituents, helps drive pathological immune activation. Novel therapeutic approaches to inhibit microbial translocation and/or attenuate chronic immune activation in HIV-infected individuals may complement treatments aimed at direct suppression of viral replication. 相似文献
970.
Jong-Min Lee Jie Zhang Andrew I Su John R Walker Tim Wiltshire Kihwa Kang Ella Dragileva Tammy Gillis Edith T Lopez Marie-Josee Boily Michel Cyr Isaac Kohane James F Gusella Marcy E MacDonald Vanessa C Wheeler 《BMC systems biology》2010,4(1):1-16