The enzymatic synthesis of 5-amino-4-imidazolecarboxamide riboside triphosphate (ZTP)

5-Amino-4-imidazolecarboxamide riboside triphosphate (ZTP) is thought to play a regulatory role in cellular metabolism. Unlike other nucleoside triphosphates, ZTP is synthesized in a one-step reaction in which the pyrophosphate group of 5-phosphoribosyl-l-pyrophosphate is transferred to the riboside monophosphate (ZMP) in a reaction catalyzed by 5-phosphoribosyl-l-pyrophosphate synthetase; reversal of this reaction leads to dephosphorylation of ZTP to ZMP. This unusual route of synthesis (and catabolism) of ZTP may be important in defining its metabolic effects in the cell.     

Characterization of <Emphasis Type="Italic">Dickeya</Emphasis> and <Emphasis Type="Italic">Pectobacterium</Emphasis> strains obtained from diseased potato plants in different climatic conditions of Norway and Poland

Soft rot and blackleg of potato caused by pectinolytic bacteria lead to severe economic losses in potato production worldwide. To investigate the species composition of bacteria causing soft rot and black leg of potato in Norway and Poland, bacteria were isolated from potato tubers and stems. Forty-one Norwegian strains and 42 Polish strains that formed cavities on pectate medium were selected for potato tuber maceration assays and sequencing of three housekeeping genes (dnaX, icdA and mdh) for species identification and phylogenetic analysis. The distribution of the species causing soft rot and blackleg in Norway and Poland differed: we have demonstrated that mainly P. atrosepticum and P. c. subsp. carotovorum are the causal agents of soft rot and blackleg of potatoes in Norway, while P. wasabiae was identified as one of the most important soft rot pathogens in Poland. In contrast to the other European countries, D. solani seem not to be a major pathogen of potato in Norway and Poland. The Norwegian and Polish P. c. subsp. carotovorum and P. wasabiae strains did not cluster with type strains of the respective species in the phylogenetic analysis, which underlines the taxonomic complexity of the genus Pectobacterium. No correlation between the country of origin and clustering of the strains was observed. All strains tested in this study were able to macerate potato tissue. The ability to macerate potato tissue was significantly greater for the P. c. subsp. carotovorum and Dickeya spp., compared to P. atrosepticum and P. wasabiae.     

Comparative studies on some yield contributing traits of wheat sown in binary mixtures

Cultivar mixtures have been suggested as ways to increase crop productivity. This field study was conducted to investigate the competition among five cultivated varieties of wheat (Triticum aestivum L.) for the traits like plant height, flag leaf area, fertile tillers per plant, spike length, spikelets per spike, spike density, grain weight per spike, and seed index in relation to competition with yield per plant. It was observed that cultivar mixtures ought to be more productive than corresponding pure stands. Four binary combinations of Seher2006-Kohistan97, Farid2006-SH2002, SH2002-Shahkar95, and SH2002-Kohistan97 were superior in performance, showing land equivalent ratio (LER) values greater than one for plant height, fertile tillers per plant, spike density, grain weight per spike, and grain yield per plant. It was observed that the performance of binary mixtures was mainly due to the increased average performance in spike density, grain weight per spike, and grain yield per plant. The competitive ability of wheat varieties in mixtures was independent of each other for the respective traits, which lead to cumulative effects for the increased performance within the associates in mixtures.     

Zooplankton diversity of a protected and vulnerable wetland system in southern South America (Llancanelo area,Argentina)

In arid regions, climatic conditions exert a great control on the aquatic systems present, but recent changes in climate have produced an enhanced salinization of the aquatic environments located there. Consequently, a major reduction in biodiversity would be expected in those wetlands that were originally fresh water. Salinity is a principal cause of reduced biodiversity particularly in zooplankton because few of those species can adapt to the salt pressure of saline environments. Therefore, the aim of this study was to gain essential information on the diversity of aquatic invertebrates in Llancanelo basin by focussing the analysis on the zooplankton community and exploring seasonal and spatial differences in the zooplankton assemblages of this vulnerable wetland system within an arid region of Argentina. Seasonal samples were taken at nine sites in the basin (a shallow lake, 4 springs, streams, and the Malargüe River). A total of 45 species were identified. The zooplankton abundance in the lake displayed a clear seasonal contrast and was higher than that recorded in the springs and lotic environments. Boeckella poopoensis, Fabrea salina, and Brachionus plicatilis predominated in the lake, indicating their halophilia. The presence of the crustaceans Alona sp., Macrocyclops albidus, and Paracyclops fimbriatus was restricted to the springs; whereas Notholca labis and Notholca squamula were found only in running water. The zooplankton species richness in the Llancanelo area is low because of both the salt content in the lake and the irregularity of freshwater entry in all locations during the annual cycle.     

Fast access of some grape pigments to the brain

Anthocyanins represent the main flavonoid pigments in red grape and wine, in red berries, and in many other fruits and vegetables and are widespread in the human diet. After ingestion, these complex, hydrophilic compounds quickly appear as intact molecules in the plasma. This study investigated their presence in the brain of anesthetized rats that received 8 mg/kg of body weight of a pure anthocyanin mixture extracted from Vitis vinifera grapes. The mixture was maintained in the stomach for 10 min. After this time, intact anthocyanins were detected by HPLC-DAD-MS not only in the plasma (176.4 +/- 50.5 ng/mL, mean +/- SEM) but also in the brain (192.2 +/- 57.5 ng/g). These results demonstrate for the first time that grape pigments can reach the mammalian brain within minutes from their introduction into the stomach.     

Episodic recruitment of young Prochilodus lineatus (Valenciennes, 1836) (Characiformes: Prochilodontidae) during high discharge in a floodplain lake of the River Paraná, Argentina

Prochilodus lineatus (Val.) is one of the main target species of South American freshwater fisheries. The following null hypotheses regarding juvenile recruitment of P. lineatus were tested: (a) recruitment is not determined by variations in larval abundance and (b) recruitment is not determined by variations in discharge. For this purpose, variations in abundance of larvae in main channel drift and monthly captures of juveniles in a floodplain lake of the River Paraná were examined weekly between 2009 and 2016. Mean annual abundances of larval densities and CPUE of juveniles were correlated with a set of hydrometric variables. A positive correlation was found between the abundance of juveniles with high and persistent flood pulses. By contrast, larval abundance was not correlated with juvenile abundance. Pronounced contrast was found in the recruitment of P. lineatus between years of high and low discharge, which supports the hypothesis that floods are the main determining factor for recruitment of this species.     

Improvement of mitochondrial function in muscle of genetically obese rats after chronic supplementation with proanthocyanidins

The aim of this study was to determine the effect of chronic dietary supplementation of a grape seed proanthocyanidin extract (GSPE) at a dose of 35 mg/kg body weight on energy metabolism and mitochondrial function in the skeletal muscle of Zucker obese rats. Three groups of 10 animals each were used: lean Fa/fa lean group (LG) rats, a control fa/fa obese group (OG) of rats, and an obese supplemented fa/fa proanthocyanidins obese group (POG) of rats, which were supplemented with a dose of 35 mg GSPE/kg of body weight/day during the 68 days of experimentation. Skeletal muscle energy metabolism was evaluated by determining enzyme activities, key metabolic gene expression, and immunoblotting of oxidative phosphorylation complexes. Mitochondrial function was analyzed by high-resolution respirometry using both a glycosidic and a lipid substrate. In muscle, chronic GSPE administration decreased citrate synthase activity, the amount of oxidative phosphorylation complexes I and II, and Nrf1 gene expression, without any effects on the mitochondrial oxidative capacity. This situation was associated with lower reactive oxygen species (ROS) generation. Additionally, GSPE administration enhanced the ability to oxidize pyruvate, and it also increased the activity of enzymes involved in oxidative phosphorylation including cytochrome c oxidase. There is strong evidence to suggest that GSPE administration stimulates mitochondrial function in skeletal muscle specifically by increasing the capacity to oxidize pyruvate and contributes to reduced muscle ROS generation in obese Zucker rats.     

Estimation of the clinical and economic consequences of non-compliance with antimicrobial treatment of canine skin infections

The goal of this study was to estimate the health and economic consequences of non-compliance with oral antimicrobial treatment in dogs with superficial pyoderma, wounds or abscesses in the US. A mathematical model (Markov model) which simulated treatment with long-term injectable cefovecin versus oral amoxicillin/clavulanic acid was developed and accounted for the effect of non-compliance on clinical outcomes and mean total treatment costs per patient. Efficacy parameters considered in the model were derived from clinical studies. Treatment failure due to oral antimicrobial treatment non-compliance was approximated from published data at 13.6%. US cost data for 2009 were derived from public sources. When non-compliance was considered as a cause of treatment failure with oral medication, the long-term injectable antibiotic was more effective than oral comparator (162 versus 158 days without clinical signs). Mean total treatment costs were lower with cefovecin (USD 376.74) versus amoxicillin/clavulanic acid (USD 382.34) in dogs of 25 kg; and cefovecin remained cost-saving up to a body weight of 31 kg. In large dogs, cefovecin was more costly; however, total therapy costs were less than 6% greater than with amoxicillin/clavulanic acid. Accordingly the higher drug and administration costs of the long-term injectable antibiotic were totally or substantially offset when non-compliance was considered as reason for treatment failure with oral medication. The model also allowed for the estimation of the impact of various non-compliance scenarios.     

Determinants of farmers’ choice for veterinary service providers in Nepal Mountains

This study was aimed to analyze factors that affect farmers' choice for major actors of veterinary service providers in village areas of Kaski district of Nepal, with the objective of identifying choice-specific attributes which could be addressed for improving the penetration of professional veterinary services in village areas. The information was obtained from 125 farmers using a structured questionnaire. A proportional hazard model was used for data analysis because of its ability to accommodate the attributes of both the chooser and the choice simultaneously. The results showed that village animal health workers (VAHWs) were the most preferred service providers followed by veterinarians and mid-level technicians. The farmers' age and education level had a significant but inverse relationship with the probability of choosing any of the three service providers. From our study, we found that the main choice-specific attributes with a significant impact on the choice probability was the distance to the preferred service provider. Since there was a high preference for VAHW, this suggests the possibility of poorly trained service providers dominating veterinary service market in village areas of Kaski district. Hence, the efforts put forward in the legalization of VAHW system in Nepal should first address the constraints that obstruct the accessibility of professional veterinary service providers in village areas.     

Dissemination of Clostridium difficile spores between environment and households: Dog paws and shoes

Clostridium difficile is an anaerobic, spore‐forming bacterium that causes intestinal infections. Although C. difficile is still predominantly considered as a nosocomial pathogen, there has been an increase in the number of community‐associated infections. Since C. difficile is ubiquitous and can be isolated from nearly any environment, one of the possibilities for community acquisition could be exposure to spores in the domestic environment. The aim of this study was to evaluate the presence of C. difficile spores on shoes, slippers and on dog paws and to explore the importance of these surfaces as vectors for the dissemination of C. difficile in a domestic environment. Overall, C. difficile was present in 14 (70%) of 20 households and in 31 of 90 (34%) collected samples. Shoes and slippers had the highest positivity rates, 19 of 44 (43%) and 6 of 21 (28%), respectively, followed by dog paws 6 of 25 (24%). Thirteen C. difficilePCR ribotypes were identified with half of the isolates belonging to ribotype 014/020, which is the predominant type circulating in human population and is also commonly found in the environment (e.g. soil and water) in Slovenia. In three households, identical PCR ribotypes were found on dog paws, shoes and slippers. To understand the fine‐scale genetic relatedness of these isolates, we sequenced the genomes. Low level of single nucleotide variant (SNV) differences between isolates from the same households, consistent with a recent transmission from a common source, were seen for isolates of PCR ribotype 014/020 but not for PCR ribotype 010. Our results suggest that shoe soles and dog paws could serve for the dissemination of C. difficile spores between households and environment and could contribute to community‐relevant sources for C. difficile infection in humans.