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101.
Chandni Praveen Brooke A. Dancho David H. Kingsley Kevin R. Calci Gloria K. Meade Kristina D. Mena Suresh D. Pillai 《Applied and environmental microbiology》2013,79(12):3796-3801
Consumption of raw oysters is an exposure route for human norovirus (NoV) and hepatitis A virus (HAV). Therefore, efficient postharvest oyster treatment technology is needed to reduce public health risks. This study evaluated the inactivation of HAV and the NoV research surrogate, murine norovirus-1 (MNV-1), in oysters (Crassostrea virginica) by electron beam (E-beam) irradiation. The reduction of potential infection risks was quantified for E-beam irradiation technology employed on raw oysters at various virus contamination levels. The E-beam dose required to reduce the MNV and HAV titer by 90% (D10 value) in whole oysters was 4.05 (standard deviations [SD], ±0.63) and 4.83 (SD, ±0.08) kGy, respectively. Microbial risk assessment suggests that if a typical serving of 12 raw oysters was contaminated with 105 PFU, a 5-kGy treatment would achieve a 12% reduction (from 4.49 out of 10 persons to 3.95 out of 10 persons) in NoV infection and a 16% reduction (from 9.21 out of 10 persons to 7.76 out of 10 persons) in HAV infections. If the serving size contained only 102 PFU of viruses, a 5-kGy treatment would achieve a 26% reduction (2.74 out of 10 persons to 2.03 out of 10 persons) of NoV and 91% reduction (2.1 out of 10 persons to 1.93 out of 100 persons) of HAV infection risks. This study shows that although E-beam processing cannot completely eliminate the risk of viral illness, infection risks can be reduced. 相似文献
102.
Gloria Arratia F. Augusto Chang G. Silvina Menu Marque Guido Rojas M. 《Studies on Neotropical Fauna and Environment》2013,48(3-4):157-194
A new genus of the family Trichomycteridae, Bullockia, and a new species of Trichomycterus are described. Bullockia gen. nov. is a monospecific and relict genus in the freshwaters of Chile. Trichomycterus mendozensis n. sp. is a freshwater relict from Argentina. Preliminary diagnoses of the subfamilies Pygidiinae and Nematogenyinae and the genera Trichomycterus, Hatcheria and Nematogenys are given. 相似文献
103.
104.
Pola Becerril-Montes Salvador Said-Fernández Julieta Luna-Herrera Guillermo Caballero-Olín José Antonio Enciso-Moreno Herminia Guadalupe Martínez-Rodríguez Gerardo Padilla-Rivas Elsa Nancy-Garza-Trevi?o Gloria María Molina-Salinas 《Memórias do Instituto Oswaldo Cruz》2013,108(2):160-166
The resistance of 139 Mycobacterium tuberculosis (MTB) isolates from the city of Monterrey, Northeast Mexico, to first and second-line anti-TB drugs was analysed. A total of 73 isolates were susceptible and 66 were resistant to anti-TB drugs. Monoresistance to streptomycin, isoniazid (INH) and ethambutol was observed in 29 cases. Resistance to INH was found in 52 cases and in 29 cases INH resistance was combined with resistance to two or three drugs. A total of 24 isolates were multidrug-resistant (MDR) resistant to at least INH and rifampicin and 11 MDR cases were resistant to five drugs. The proportion of MDR-TB among new TB cases in our target population was 0.72% (1/139 cases). The proportion of MDR-TB among previously treated cases was 25.18% (35/139 cases). The 13 polyresistant and 24 MDR isolates were assayed against the following seven second-line drugs: amikacin (AMK), kanamycin (KAN), capreomycin (CAP), clofazimine (CLF), ethionamide (ETH), ofloxacin (OFL) and cycloserine (CLS). Resistance to CLF, OFL or CLS was not observed. Resistance was detected to ETH (10.80%) and to AMK (2.70%), KAN (2.70%) and CAP (2.70%). One isolate of MDR with primary resistance was also resistant to three second-line drugs. Monterrey has a high prevalence of MDR-TB among previously treated cases and extensively drug-resistant-MTB strains may soon appear. 相似文献
105.
Haythem Gharsa Karim Ben Slama Elena Gómez-Sanz Carmen Lozano Naouel Klibi Ahlem Jouini Lilia Messadi Abdellatif Boudabous Carmen Torres 《Microbial ecology》2013,66(2):363-368
Nasal swabs of 100 healthy dogs were obtained in 2011 in Tunisia and tested for Staphylococcus pseudintermedius recovery. Antimicrobial resistance profile and virulence gene content were determined. Multilocus-sequence-typing (MLST) and SmaI-pulsed-field gel electrophoresis (PFGE) were investigated. S. pseudintermedius was recovered in 55 of the 100 tested samples (55 %), and one isolate per sample was further studied. All 55 S. pseudintermedius isolates were susceptible to methicillin (MSSP) but showed resistance to the following antimicrobials (% resistant isolates/resistance gene): penicillin (56.4/blaZ), tetracycline (40/tetM), trimethoprim-sulfamethoxazole (23.7), fusidic acid (9), kanamycin (3.7/aph(3´)-Ia), erythromycin-clindamycin (1.8/erm(B)), streptomycin (1.8/ant(6)-Ia), chloramphenicol (1.8) and ciprofloxacin (1.8). The following toxin genes were identified (% of isolates): lukS/F-I (98.2), expA (5.5), se-int (98.2), sec canine (1.8), siet (100), sea (5.5), seb (3.6), sec (10.9), sed (54.5), sei (5.5), sej (29.1), sek (3.6), ser (9.1), and hlg v (38.2). Ten different sequence-types were detected among 11 representative MSSP isolates: ST20, ST44, ST69, ST70, ST78, ST100, ST108, ST160, ST161, and ST162, the last three ones revealing novel alleles or allele combinations. Eleven different PFGE-patterns were identified in these isolates. The nares of healthy dogs could be a reservoir of antimicrobial resistant and virulent MSSP, highlighting the presence of the recently described exfoliating gene expA and several enterotoxin genes. 相似文献
106.
107.
M. Gloria Esquivel Todor Genkov Ana S. Nogueira Michael E. Salvucci Robert J. Spreitzer 《Photosynthesis research》2013,118(3):209-218
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyzes the initial step of carbon metabolism in photosynthesis. The holoenzyme comprises eight large subunits, arranged as a tetramer of dimers around a central solvent channel that defines a fourfold axis of symmetry, and eight small subunits, arranged as two tetramers at the poles of the axis. The phylogenetically divergent small-subunit loops between β-strands A and B form the entrance to the solvent channel. In the green alga Chlamydomonas reinhardtii, Ile-58 from each of the four small-subunit βA–βB loops defines the minimal diameter of the channel opening. To understand the role of the central solvent channel in Rubisco function, directed mutagenesis and transformation of Chlamydomonas were employed to replace Ile-58 with Ala, Lys, Glu, Trp, or three Trp residues (I58W3) to close the entrance to the channel. The I58E, I58K, and I58W substitutions caused only small decreases in photosynthetic growth at 25 and 35 °C, whereas I58W3 had a substantial effect at both temperatures. The mutant enzymes had decreased carboxylation rates, but the I58W3 enzyme had decreases in both carboxylation and CO2/O2 specificity. The I58E, I58W, and I58W3 enzymes were inactivated at lower temperatures than wild-type Rubisco, and were degraded at slower rates under oxidative stress. However, these mutant enzymes were activated by Rubisco activase at normal rates, indicating that the structural transition required for carboxylation is not affected by altering the solvent channel opening. Structural dynamics alone may not be responsible for these distant effects on the Rubisco active site. 相似文献
108.
109.
In the city of Santiago (33°27'S70°38'W), Chile, an atmospheric pollen was monitored for three years using a volumetric Hirst-type pollen trap. The aims of the study were: to assess the pollen types present in the atmosphere, their actual concentrations and dynamics (means and maxima); to establish the pollen calendar for Santiago; and to analyze the aerobiologic characteristics distinguishing introduced and native taxa. Results show that atmospheric pollen mainly originates from the following taxa: Platanus , Poaceae, Acer , Cupressus , Chenopodiaceae, Urticaceae, Morus , Plantago and Oleaceae. For the most frequent pollen types graphs of their atmospheric presence constructed and a table with relevant yearly data for the three studied (July-June) is presented. It is concluded, that the airborne pollen is originating mainly from introduced taxa, many of which are considered allergenic. Native taxa showed no high concentrations. The highest aiborne pollen concentrations where observed in September, however, atmospheric pollen thought to be capable of causing pollinosis, where present during the whole year. The highest pollen concentrations are mostly from trees. 相似文献
110.
Stacy Van Epps Bryan Fiamengo Jeremy Edmunds Anna Ericsson Kristine Frank Michael Friedman Dawn George Jonathan George Eric Goedken Brian Kotecki Gloria Martinez Philip Merta Michael Morytko Shashank Shekhar Barbara Skinner Kent Stewart Jeffrey Voss Grier Wallace Neil Wishart 《Bioorganic & medicinal chemistry letters》2013,23(3):693-698
Interest in therapeutic kinase inhibitors continues to grow beyond success in oncology. To date, ATP-mimetic kinase inhibitors have focused primarily on monocyclic and bicyclic heterocyclic cores. We sought to expand on the repertoire of potential cores for kinase inhibition by exploring tricyclic variants of classical bicyclic hinge binding motifs such as pyrrolopyridine and pyrrolopyrazine. Herein we describe the syntheses of eight alternative tricyclic cores as well as in vitro screening results for representative kinases of potential therapeutic interest. 相似文献