Environmental Drivers for Persistence of Escherichia coli and Salmonella in Manure-Amended Soils: A Meta-Analysis.

ABSTRACT: Application of organic amendments to agricultural land improves soil quality and provides nutrients essential for plant growth; however, they are also a reservoir for zoonotic pathogens whose presence poses a significant risk to public health. The persistence of bacteria in manure-amended soil, and differences in manure handling practices, are important issues from a food safety perspective. The primary objective of this study was to quantitatively summarize the variations in the rate of decline of Escherichia coli and Salmonella spp. in manure-amended soil under laboratory and field conditions, and to assess the impact of environmental factors. Available literature data on persistence of E. coli and Salmonella spp. in manure-amended soil from 42 primary research studies were extracted and statistically analyzed using a mixed-effect regression model. The results indicated that temperature (soil and air combined) was the most prominent factor affecting persistence of both E. coli and Salmonella spp. under laboratory conditions (P < 0.001), and of E. coli under field conditions (P < 0.05). The time required for a log reduction of E. coli under field conditions was significantly higher at low temperature (0 to 10°C) than at high temperature (greater than 20°C) (P < 0.05). In addition, application method was identified as a significant factor, with manure incorporation to soil inducing longer survival compared with surface application by approximately 1.2 times. The significant variation observed among primary research studies of bacterial persistence has highlighted that mitigation strategies associated with the use of manures in fresh produce production need to be improved by addressing factors such as climate, soil management, application method, and initial microbial levels. These findings may be used to support guidelines establishing exclusion periods between manure fertilization and the grazing or harvesting of crops, and may be useful for the generation of quantitative microbial risk models for fresh produce.

[Comparison of the concept of forensic medicine in Southeastern Asia and Central Europe]. / Srovnání koncepce soudního lékarství v jiho-východoasijském a stredoevropském regionu.

Differences in conception of forensic medicine in the central Europe and south-eastern Asia are consisted in both legislative difference and different view of religion as well in fact, that forensic medicine is a very young subject in Vietnam and in some nearby countries that dispose of not enough professional workplaces and specialists. In this point, an intense reverse is coming about, especially owning to possibility of an abroad study of this subject in countries that have longer tradition.

[Findings in the detection of fibronectin in skin burns]. / Nekteré poznatky získané pri prukazu fibronectinu u popálenin kuze.

Occurrence of fibronectin was detected in paraffin sections of burn skin samples, excised from surviving patients, as well as skin samples removed from the death persons, who succumbed burn wounds. The other groups of samples, used for comparison with the previous one, consisted of the intact skin excisions and skin samples post-mortem exposed to thermic changes. Indirect immunoperoxidase reaction was the immunohistochemical method used in all examinations. In post-mortem burn skin samples there was a loss of fibronectin activity in the epidermo-dermal junction area as well as in the papillary dermis. In burn skin samples, excised from patients who only survived for very short time their (serious skin) burns, no evidence of any fibronectin activity was seen. Also in two other cases, when patients--due to their severe burns--survived for several hours only, there were no conspicuous differences in the intensity of fibronectin activity seen in comparison with features found in the intact skin samples. Fibronectin activity was, however, increased in all other burn skin samples, where the survival time of patients was from 30 minutes to 5 weeks and there were following differences in its intensity and also in its pattern of distribution. In the 1st-degree and in a superficial 2nd-degree skin burn wounds, fibronectin was also present in the epidermis. In the papillary dermis, fibronectin was distributed rather diffusely or in a spot-like pattern while in the reticular dermis, there was a tendency to form net-like structures among collagen fibers. In deeper 2nd-degree and in the 3rd-degree burn wounds, fibronectin was deposited in vicinity of blood vessels and skin appendages in a fibrillar pattern. In 6 out of 11 samples, where the survival time ranged from 7 to 21 days, fibroblasts were arranged among fine collagen fibers and some of these cells exhibited positive fibronectin activity on their surface. Numerous fibroblasts with finely scattered fibronectin spots and also a decrease of fibronectin activity were observed in more mature granulation tissue, present in burn skin samples where survival time of patients was five weeks.