Protection of palmitic acid treatment in RAW264.7 cells and BALB/c mice during Brucella abortus 544 infection

BackgroundWe previously elucidated the protective mechanism of Korean red ginseng oil (RGO) against Brucella abortus infection, and our phytochemical analysis revealed that palmitic acid (PA) was an abundant component of RGO. Consequently, we investigated the contribution of PA against B. abortus.ObjectivesWe aimed to investigate the efficacy of PA against B. abortus infection using a murine cell line and a murine model.MethodsCell viability, bactericidal, internalization, and intracellular replication, western blot, nitric oxide (NO), and superoxide (O₂^-) analyses and flow cytometry were performed to determine the effects of PA on the progression of B. abortus infection in macrophages. Flow cytometry for cytokine analysis of serum samples and bacterial counts from the spleens were performed to determine the effect of PA in a mouse model.ResultsPA did not affect the growth of B. abortus. PA treatment in macrophages did not change B. abortus uptake but it did attenuate the intracellular survivability of B. abortus. Incubation of cells with PA resulted in a modest increase in sirtuin 1 (SIRT1) expression. Compared to control cells, reduced nitrite accumulation, augmented O₂^-, and enhanced pro-inflammatory cytokine production were observed in PA-treated B. abortus-infected cells. Mice orally treated with PA displayed a decreased serum interleukin-10 level and enhanced bacterial resistance.ConclusionsOur results suggest that PA participates in the control of B. abortus within murine macrophages, and the in vivo study results confirm its efficacy against the infection. However, further investigations are encouraged to completely characterize the mechanisms involved in the inhibition of B. abortus infection by fatty acids.     

Evaluation of the discriminance capacity of RAPD, isoenzymes and morphologic markers in apple (Malus x domestica Borkh.) and the congruence among classifications

Twenty-one apple accessions were characterised and classified taxonomically with randomly amplified polymorphic DNA (RAPD). The results were compared with morphological and isoenzymatic classifications of the same material by calculating the congruence between similarity matrices. The results confirmed the greater discrimination capacity of RAPD compared with isoenzymes, although the taxonomic clusters obtained with both types of markers were congruent. The genetic relationships calculated using RAPD and isoenzymes showed little congruence with the morphological relationships among accessions. Isoenzymatic markers are useful in germplasm banks to evaluate the diversity of newly introduced accessions. The use of RAPD markers are especially beneficial to discriminate between material that is genetically similar, to evaluate genetic variability within a collection and to choose the components of the core collection.     

Bacterial analysis of Chromobacterium sp. and Flavobacterium sp. in a waste stabilization pond system

A survey on Chromobacterium sp. and Flavobacterium sp. was conducted in a waste stabilization pond system at Santo Tomas Atzingo, State of Mexico. For this purpose methods for the isolation and identification of Chromobacterium sp. and Flavobacterium sp. from wastewater were developed and proved to be efficient. Such methods are the result of combining and modifying a series of previously reported techniques for this genera strains, but for environments different from wastewater.     

Earth-Based Observations of the Galileo Probe Entry Site

Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile.     

Operant reward learning in Aplysia: neuronal correlates and mechanisms

Operant conditioning is a form of associative learning through which an animal learns about the consequences of its behavior. Here, we report an appetitive operant conditioning procedure in Aplysia that induces long-term memory. Biophysical changes that accompanied the memory were found in an identified neuron (cell B51) that is considered critical for the expression of behavior that was rewarded. Similar cellular changes in B51 were produced by contingent reinforcement of B51 with dopamine in a single-cell analog of the operant procedure. These findings allow for the detailed analysis of the cellular and molecular processes underlying operant conditioning.     

Effects of Lime‐Cooking on Carotenoids Present in Masa and Tortillas Produced from Different Types of Maize

Yellow and white maize kernels, masas, tortillas, and nejayote solids were analyzed in terms of lutein, zeaxanthin, cryptoxanthin, β‐carotene, and lipophilic antioxidant (AOX) capacity. The germplasm analyzed included two normal yellow maize, two high‐carotenoid genotypes, and one white for comparison purposes. In general, the yellow maize required 34% more lime‐cooking time compared with the white counterpart. Lime‐cooking significantly changed the extractability of carotenoids in masa and tortillas. No carotenoids were detected in the steepwater or nejayote. The lipophilic AOX activity increased 280‐fold from kernel to masa, but only 70% was retained in the baked tortillas. When masa was baked into tortillas, less than 10% of the carotenoids were retained because of the high temperatures used during baking. Interestingly, tortillas made with the maize kernels with the highest carotenoid content did not have the highest amount of these phytochemicals. Therefore, maize varieties should be evaluated based on the carotenoid content in finished food products instead of the amounts originally found in raw kernels.     

Infectious haemolytic anaemia causes jaundice outbreaks in seawater-cultured coho salmon, Oncorhynchus kisutch (Walbaum), in Chile

In the last 9 years, epizootics of an icterus condition has affected coho salmon, Oncorhynchus kisutch (Walbaum), reared in seawater cages in southern regions of Chile. At necropsy, fish from field cases exhibited signs of jaundice accompanied by pale light-brown livers and dark spleens. Histopathological and haematological results indicated that these fish presented haemolytic anaemia. After microbiological examination no bacterial or viral agents could be identified as aetiological agents of this disease. In an infectivity trial, coho salmon, Atlantic salmon, Salmo salar L., and rainbow trout, Oncorhynchus mykiss (Walbaum), were inoculated intraperitoneally with a filtrate of an organ homogenate (0.45 microm) from a diseased coho salmon and held for 60 days in tanks supplied with fresh water. The disease was only reproduced in coho salmon in which mortalities, beginning at day 23 post-inoculation (p.i.), reached a cumulative value of 24% at day 27 p.i. This condition was transmitted to non-inoculated cohabiting coho salmon suggesting that it is a waterborne disease. Thus, this icteric condition is caused by an infectious form of haemolytic anaemia, probably of viral aetiology, and coho salmon are more susceptible than either Atlantic salmon or rainbow trout.     

Anaerobic biotransformation of organo-arsenical pesticides monomethylarsonic acid and dimethylarsinic acid

Monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) are extensively utilized as pesticides, introducing large quantities of arsenic into the environment. Once released into the environment, these organo-arsenicals are subject to microbial reactions. Aerobic biodegradation of MMAV and DMAV has been evaluated, but little is known about their fate in anaerobic environments. The objective of this study was to evaluate the biotransformation of MMAV and DMAV in anaerobic sludge. Biologically mediated conversion occurred under methanogenic or sulfate-reducing conditions but not in the presence of nitrate. Monomethylarsonous acid (MMAIII) was consistently observed as an important metabolite of MMAV degradation, and it was recovered in molar yields ranging from 5 to 47%. The main biotransformation product identified from DMAV metabolism was MMAV, which was recovered in molar yields ranging from 8 to 65%. The metabolites indicate that reduction and demethylation are important steps in the anaerobic bioconversion of MMAV and DMAV, respectively.     

Multidrug‐Resistant Outbreak‐Associated Salmonella Strains in Irrigation Water from the Metropolitan Region,Chile

Salmonella enterica (S. enterica) is the main cause of foodborne diseases in the Chilean population. With the aim of characterizing the presence of S. enterica in bodies of water, samples from 40 sources were obtained, including rivers and irrigation canals used by agricultural farms in the most populated regions of Chile. As result, 35 S. enterica isolates belonging to several serotypes were detected, with the highest frequency represented by Typhimurium and Enteritidis. All strains showed phenotypic antimicrobial resistance, and most of them were multiresistant to critically important antimicrobials. In addition, the pulse‐field gel electrophoresis analysis using XbaI and BlnI endonucleases showed that seven Salmonella isolates belonging to serotypes Typhimurium, Enteritidis and Infantis had identical pulsotypes to outbreak‐associated clinical isolates detected in the Chilean population, suggesting a public health risk of water pollution in this region. Among sampling sites, the higher detection rates were observed in rural than urban and peri‐urban areas, suggesting that the animal husbandry might contribute for environmental dispersion of this pathogen. Future efforts should address the characterization of cause‐and‐effect relationship between water contamination and foodborne disease, including the implementation of surveillance programmes to tackle potential risks for both human and animal populations.