Levels of antibiotic resistance genes in manure, biosolids, and fertilized soil

Increasing antibiotic resistance genes in the environment may pose a threat to public health. In this study, tetracycline and sulfonamide resistance genes (Tet-W, Tet-O, and Sul-I) were quantified in 24 manure samples from three farms and 18 biosolids samples from seven different wastewater treatment plants using quantitative polymerase chain reaction methods. Concentrations of Tet-W and Tet-O genes were observed to be significantly higher (p < 0.05) in manure than in biosolids samples. The background soil samples showed significantly lower concentration of the above genes compared with manure and biosolids. Lime-stabilized biosolids showed significantly (p < 0.05) lower concentration of antibiotic resistance genes compared with other biosolids treatment methods. Elevated levels of antibiotic resistance genes (Tet-W, Tet-O, and Sul-I) were observed in the amended soil samples after the land application of manure or biosolids (Site A) monitored for a period of about 4 mo. However, at another site (Site B), no significant increase (p > 0.05) in concentration of antibiotic resistance genes was observed after biosolids application on soil. Even though the concentration of antibiotic resistance genes in manure was statistically higher than that in biosolids, when they were applied on land, the contribution to the soil depended on the background soil concentration and the soil characteristics. Further study of multiple soil samples in various locations is needed.     

Suitability of the vegetation types in Mexico's Tamaulipas state for the siting of hazardous waste treatment plants

A land suitability study was carried out by applying a multiple-criteria technique to 12 different vegetation types in Mexico's Tamaulipas state to help select potentially suitable sites for hazardous waste treatment plants. Species richness, spatial distribution, and uniqueness were selected as the criteria for estimating a vegetation type's suitability. Using the analytical hierarchy process, we ranked and mapped vegetation types, then compared the results with rankings of the same vegetation types based only on their number of endemic species. The suitabilities of the various vegetation types were ordered in more or less the same way by both methods, except in two cases for which the results were very different. The method proved to be a useful tool despite the availability of only partial (mostly qualitative) information; under such circumstances, expert experience can be incorporated in the evaluation process to a limited degree. The technique described in this paper has a high potential to aid decisions when many opinions and options must be considered simultaneously.     

A prospective study on rapid exome sequencing as a diagnostic test for multiple congenital anomalies on fetal ultrasound

Objective

Conventional genetic tests (quantitative fluorescent-PCR [QF-PCR] and single nucleotide polymorphism-array) only diagnose ~40% of fetuses showing ultrasound abnormalities. Rapid exome sequencing (rES) may improve this diagnostic yield, but includes challenges such as uncertainties in fetal phenotyping, variant interpretation, incidental unsolicited findings, and rapid turnaround times. In this study, we implemented rES in prenatal care to increase diagnostic yield.

Methods

We prospectively studied 55 fetuses. Inclusion criteria were: (a) two or more independent major fetal anomalies, (b) hydrops fetalis or bilateral renal cysts alone, or (c) one major fetal anomaly and a first-degree relative with the same anomaly. In addition to conventional genetic tests, we performed trio rES analysis using a custom virtual gene panel of ~3850 Online Mendelian Inheritance in Man (OMIM) genes.

Results

We established a genetic rES-based diagnosis in 8 out of 23 fetuses (35%) without QF-PCR or array abnormalities. Diagnoses included MIRAGE (SAMD9), Zellweger (PEX1), Walker-Warburg (POMGNT1), Noonan (PTNP11), Kabuki (KMT2D), and CHARGE (CHD7) syndrome and two cases of Osteogenesis Imperfecta type 2 (COL1A1). In six cases, rES diagnosis aided perinatal management. The median turnaround time was 14 (range 8-20) days.

Conclusion

Implementing rES as a routine test in the prenatal setting is challenging but technically feasible, with a promising diagnostic yield and significant clinical relevance.     

Effect of soluble maillard reaction products on cadA expression in Salmonella typhimurium

The presence of Maillard reaction products (MRP) in foods and food components is due to the non-enzymatic reaction between protein and carbohydrate residues triggered by thermal steps during food processing. The objective of this study was to assess the effect of MRPs and increasing lysine concentrations on S. Typhimurium growth and the expression of cadA which may be an indirect determinant of Salmonella virulence response. Variations in lysine concentrations (from 0 to 0.5 mM) did not exert any effect either on the final optical density after 6-hour incubation or the growth rates of S. Typhimurium in media containing MRPs. In contrast to the reduced final absorbancy of the bacterial cultures grown with histidine and arginine MRPs supplementations (0.1%), growth rates, in general, remained unaltered by all MRPs at each lysine concentration when compared to the control (M9 pH 5.8, no MRPs added). The induction levels of cadA in media containing 0.1% MRPs were close to cadA induction in the reference media (M9, pH 5.8 and no MRPs) and did not exceed the corresponding values by more than approximately 30%. Although the observed negligible induction of cadA under these conditions complies with the concept of its potential “anti-virulence” function, additional studies involving various concentrations and more refined MRPs are needed.     

Inactivation of Viruses and Bacteriophages as Models for Swine Hepatitis E Virus in Food Matrices

Hepatitis E virus has been recognised as a food-borne virus hazard in pork products, due to its zoonotic properties. This risk can be reduced by adequate treatment of the food to inactivate food-borne viruses. We used a spectrum of viruses and bacteriophages to evaluate the effect of three food treatments: high pressure processing (HPP), lactic acid (LA) and intense light pulse (ILP) treatments. On swine liver at 400 MPa for 10 min, HPP gave log₁₀ reductions of ≥4.2, ≥5.0 and 3.4 for feline calicivirus (FCV) 2280, FCV wildtype (wt) and murine norovirus 1 (MNV 1), respectively. Escherichia coli coliphage ?X174 displayed a lower reduction of 1.1, while Escherichia coli coliphage MS2 was unaffected. For ham at 600 MPa, the corresponding reductions were 4.1, 4.4, 2.9, 1.7 and 1.3 log₁₀. LA treatment at 2.2 M gave log₁₀ reductions in the viral spectrum of 0.29–2.1 for swine liver and 0.87–3.1 for ham, with ?X174 and MNV 1, respectively, as the most stable microorganisms. The ILP treatment gave log₁₀ reductions of 1.6–2.8 for swine liver, 0.97–2.2 for ham and 1.3–2.3 for sausage, at 15–60 J cm^?2, with MS2 as the most stable microorganism. The HPP treatment gave significantly (p < 0.05) greater virus reduction on swine liver than ham for the viruses at equivalent pressure/time combinations. For ILP treatment, reductions on swine liver were significantly (p < 0.05) greater than on ham for all microorganisms. The results presented here could be used in assessments of different strategies to protect consumers against virus contamination and in advice to food producers. Conservative model indicators for the pathogenic viruses could be suggested.     

Factors influencing local ecological knowledge maintenance in Mediterranean watersheds: Insights for environmental policies

Local ecological knowledge (LEK) has been found to be one of the main bridges to manage biocultural diversity. We analyzed the factors affecting LEK maintenance and transmission in a Mediterranean watershed. We used a mixed methods approach to evaluate the agricultural LEK in three different dimensions: biological, soil and water management, and forecasting. We found that the main factors for its maintenance were the respondent''s time living in the area and the social relationships established among farmers, which involved partner collaboration and farmer information exchanges. Protected areas also played a key role for maintaining the LEK associated with soil and water management. Finally, we found that outmigration and mechanization were the most important indirect drivers of change underlying LEK erosion. We suggest that environmental policies should focus on promoting this experiential knowledge, considering both intergenerational renewal and the gendered aspects of this knowledge.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0556-1) contains supplementary material, which is available to authorized users.     

Source, concentration, and distribution of elemental mercury in the atmosphere in Toronto, Canada

Atmospheric gaseous elemental mercury [GEM] at 1.8, 4, and 59 m above ground, in parking lots, and in indoor and outdoor air was measured in Toronto City, Canada from May 2008-July 2009. The average GEM value at 1.8 m was 1.89 ± 0.62 ng m(-3). The GEM values increased with elevation. The average GEM in underground parking lots ranged from 1.37 to 7.86 ng m(-3) and was higher than those observed from the surface parking lots. The GEM in the indoor air ranged from 1.21 to 28.50 ng m(-3), was higher in the laboratories than in the offices, and was much higher than that in the outdoor air. All these indicate that buildings serve as sources of mercury to the urban atmosphere. More studies are needed to estimate the contribution of urban areas to the atmospheric mercury budget and the impact of indoor air on outdoor air quality and human health.     

The effects of organic environmental chemicals on the growth of the alga Scenedesmus subspicatus: A contribution to environmental biology

The effective concentrations of 15 chemicals, inhibiting the cell growth of the alga $\text{Scenedesmus subspicatus}$ by 10 % and 50 % during 96 hours, have been investigated in a static test under controlled laboratory conditions.