Top PDF Recombinant Technology and Probiotics

Recombinant Technology and Probiotics

Recombinant Technology and Probiotics

Recombinant technology defined as transfer of the gene of interest from one organism to the plasmid of another organism, has led the way to monumental advances in the development of useful molecules, including the development of safe probiotics [1], [2], [3], [4]-[11]. Probiotics are live microorganisms having beneficial effects on human and animal health. Beneficial microbes have been used over the centuries for food, nutrition, environment and health, and are testimony of one of the ways to food safety. Probiotics, such as dietary lactic acid bacteria (LAB) present in yoghurt are non-invasive and non-pathogenic Gram-positive bacteria that are also present in the intestine. A minimum level of 10 6 viable probiotic bacteria per milliliter or gram of food is considered adequate although the amount of cells required to produce a beneficial health effect may vary according to the strain and the health benefit desired [12]. LAB are used for food processing and preservation, and are used as starter cultures, co-cultures and bioprotective cultures in the food industry [13]. In fermented foods, LAB have been shown to produce antimicrobial compounds, such as organic acids, bacteriocins and antifungal peptides. The United States Food and Drug Administration has categorized LAB as ‘generally regarded as safe’ (GRAS). Some of the functional effects of probiotics include strengthening of the gut mucosal barrier, antimutagenic/anticarcinogenic activities, stimulation of the immune system and lowering of blood cholesterol levels [14], [15], [16]. There is growing scientific evidence by mechanistic and clinical studies that probiotics have many health benefits, including modulation of host cell metabolism [17], reduction of lactose intolerance, maintenance of balanced gut microbiota [18], prevention of colonization by opportunistic pathogens [19] and treatment /prevention of allergies [20]. A correlation between intestinal microflora and allergic diseases has been epidemiologically demonstrated [21]. Epidemiological studies have shown that reduced consumption of fermented food is one of the factors associated with rise in allergic diseases. In animals, probiotics are used to improve health status and animal performance, while in ruminants probiotics are used to improve rumen fermentation, and may mitigate methane emissions known to contribute to global greenhouse effects [22].
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Recombinant phages for Spodoptera frugiperda control: new perspectives to tackle an economic problem / Fagos recombinantes para o controle de Spodoptera frugiperda: novas perspectivas para enfrentar um problema econômico

Recombinant phages for Spodoptera frugiperda control: new perspectives to tackle an economic problem / Fagos recombinantes para o controle de Spodoptera frugiperda: novas perspectivas para enfrentar um problema econômico

Phage Display (PhD) is a high-throughput profiling technology based on peptide libraries present on the surface of bacteriophages [14]. This technique has become a tool for finding high affinity bioactive peptides since it explores the interaction sites between targets and ligands [15, 16]. Therefore, through this technology, it is possible to trace and identify new peptides that bind to the midgut proteins of the caterpillar. Oligopeptides can therefore be identified through an affinity selection strategy, making this tool extremely suitable for the identification of new molecules that act as biopesticides [17]. Although there are no reports of recombinant phage peptides for S. frugiperda, different studies have been conducted with this methodology, with particularly
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PROBIOTICS, PREBIOTICS AND SNYBIOTICS IN POULTRY MODE OF ACTION, LIMITATION, AND ACHIEVEMENTS

PROBIOTICS, PREBIOTICS AND SNYBIOTICS IN POULTRY MODE OF ACTION, LIMITATION, AND ACHIEVEMENTS

coccidiostatics. Technology in ovo eliminates some of these factors that could reduce the effectiveness of prebiotic action in poultry. The effects of this technology were tested by Drobex-Agro in a pilot study (unpublished). Compared to dietary prebiotic inclusion, in ovo technology increased the population of beneficial microflora on the day of hatch. Improved gut health may also have additional benefits in reducing the capacity for enteric viruses to establish infection in chicks and there increase the growth performance of he flock. Increased resistance to enteric poultry viruses may have the added benefit of removing additional stress factors that may be beneficial for colonization of the gut with pathogenic bacteria. Among the studies on prebiotics were also those which have shown that prebiotics do not affect largely on the animals productivity. Body weight of turkeys fed on diet with mannooligosaccharides from 4 to 20 week of age did not differ significantly compared to the control group. Similar results were reported in relation to feed conversion ratio and breast muscles mass. Prebiotics used in a mixture for fattening chickens does not affect the quality of meat chemical composition expressed (Fritts, Waldroup, 2003).
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Application of BRED technology to construct recombinant D29 reporter phage expressing EGFP

Application of BRED technology to construct recombinant D29 reporter phage expressing EGFP

With some reporter phages already developed, the next main steps into improving phenotypic assays based on bacteriophage technology are to reduce the time needed to detect M. tuberculosis and increase the sensibility of phage-based assays. The lytic phage machinery may be valuable for construction of recombinant phages present- ing high mRNA transcription rate, which can improve mRNA transcription of reporter genes. The advent of BRED technology makes possible the construction of phages containing reporter genes virtually in any portion of a bacteriophage genome under the control of any pro- moter. Using BRED technology, it was possible to insert the whole P hsp60 -egfp cassette into the genome of myco-
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Growth performance and intestinal histomorphology of Nile tilapia juveniles fed probiotics

Growth performance and intestinal histomorphology of Nile tilapia juveniles fed probiotics

Fragments of the middle portion of the intestines were removed with sterilized surgical instruments and fixed in 10% buffered formalin solution for 48 hours. The samples were then transferred to alcohol 70% G.L., and remained thus conserved until the moment of inclusion. At the Laboratory of Fish Endocrinology of the University of São Paulo (USP), the fragments were submitted to gradual dehydration in a graded alcohol series, diafanized in xylene and embedded in paraffin. The blocks obtained were then cut in 5.0 μm-thick sections, placed in histological slides stained with hematoxylin-eosin (HE) (MAIA, 1979), and analyzed under light microscope.
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Use of probiotics in atopic dermatitis

Use of probiotics in atopic dermatitis

The group also suggests the identification of PAD as dependent or independent IgE beyond the defi- nition of severity. Probiotics must meet the criteria of the European Union for research: Human origin; Non-pathogenic behavior even in immunocompro- mised patients; Resistant to technological processes; Resistant to gastric acid and bile; Adherent to the intestinal epithelium and persistent for some period in gut; Able to produce antimicrobial substances and modulate immune system; Able to influence on met- abolic activities 11 .

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Separation and Purification Technology

Separation and Purification Technology

nucleation in a complex manner. Generally, the agglomeration ker- nel increases with the primary nucleation rate while decreasing with either the volumetric growth rate or supersaturation. At 1[Ni]:1[S], the agglomeration kernel decreased with the nucleation rate (i.e., pH), but increased when the growth rate was reduced. Al- Tarazi et al. [8] reported similar behavior for both growth and nucleation rates, although the agglomeration kernel increased with pH. The increase in the agglomeration kernel with pH, however, leveled out for the experiments carried out at higher pH (6.0). When two different level of supersaturation were herein com- pared, the higher supersaturation implied a lower value of the agglomeration kernel, as expected [8], probably because higher sulfide concentrations caused a reduction in zeta potential of the solid particles (the surface charge became more negative) due to the sorption of sulfide ions [26]. Repulsion among different parti- cles was therefore stronger, resulting in smaller particles and the lowest growth rate and agglomeration kernel values depicted in Table 2.
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Internet and E-Marketing Technology

Internet and E-Marketing Technology

Marketing concept is not just a theory, but also a business philosophy, which confirms that the company aims, above all, to satisfy the demands of customers. According to this conception, the key for achieving the objectives of the organization is consisted in determining the needs and desires of target markets and transfering of desired satisfactions by more successful and effective way than competition. The mission of the company is a purpose or reason for the existence of the company. Before the company appears on the Internet, it is necessary to determine which are the reasons for this type of business to be suitable for the company. There are many questions that marketing managers need to set themselves before you take any action on the e"media. Too many organizations compete on the Internet without pre"defined goals, plans and / or methods for the evaluation of achieved results. Business objectives are defined at the level of the company in order to meet the expectations of shareholders (the founder, owner). Time range of objectives can be from one to three, five or ten or more years (long" term goals). From the practical aspects, they are set as quantitative and qualitative. Quantitative business objectives are related to the rate of income on the basis of engaged and invested capital, earnings per shareholders stocks, etc. Qualitative business objectives are related to the image and position of the company, its identity and transparency. When defining the business goals, very improtant are: company position, market position of products, productivity, competitiveness, technological and financial capacity, staff, social responsibility, profitability of products, markets and customers, achieving certain image and identity, etc.
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Supramolecular Chemistry and Technology

Supramolecular Chemistry and Technology

very similar to those of the molecular species in solution (Araki et al. 1995c) The films deposited on glassy carbon exhibit a well behaved electrochemical response in aqueous solution, displaying reversible waves at E o = 0.95 V, associated with the peripheral ruthenium groups (Fig. 10). The peak currents increase linearly as a function of the scan rate, with a small difference in the slopes arising from the non-equivalent FWHM values. These results are consistent with a fast ion diffusion and electron transfer within the film, with a minor repulsive site-to-site interaction, or differences in redox species environment. Because of their bulkiness, the mobility of the molecules within the film should be hindered, and molecular diffusion can not support a direct electron transfer to the electrode. Therefore, the electron transport within the film should occur by self-exchange or electronic conduction mechanisms. In the presence of ferrocyanide ions, no current is observed at the normal oxidation potential, e.g. 0.37 V, during the anodic scan; however, a sharp wave appears at the beginning of the Ru III / II anodic wave (0.7 V) so that the electronic conduction mechanism can definitely be ruled out. This behavior is identical to that observed in redox polymers bilayers in which the outer film electroactive species have a more negative potential than the inner one, but the electron transfer is mediated by the inner film redox species. Since the outer redox species is in solution, the solvated ferrocyanide ions can neither diffuse through nor exchange with the anions present in the film, because of the compact arrangement of the tetraruthenated nickelporphyrin molecules. Therefore, the electrochemical processes should be mediated by the film, which acts as a conduction gate, allowing an unidirectional electron flow from the solution to the electrode.
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Feasibility of Natore Rubber Dam on Mahanonda River in Bangladesh and its Performance on Irrigation

Feasibility of Natore Rubber Dam on Mahanonda River in Bangladesh and its Performance on Irrigation

The dam conserves fresh water in the upstream side and prevents flow of saline tidal water from downstream. The conserved water will be used for irrigation by lifting through low lift pumps. The dam will be operated in winter for cultivation of 6000ha Boro rice in January to May. BIC has constructed 14 Rubber Dams in Bangladesh. The construction has recommended that Rubber Dams are appropriate and cost effective water conservation structures in small and medium rivers of Bangladesh both in non-tidal and tidal locations.

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Mana  vol.3 número1

Mana vol.3 número1

“The Technology of Enchant ment and t he Enchant - ment of Technology”.. Oxf ord: Clarendon Press.[r]

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MATERIAL AND METHODS Sample collection

MATERIAL AND METHODS Sample collection

A surface sterilisation method was used, consisting of successive dipping of leaf fragments in 2% Extran (Sigma, USA) detergent (2 min), 70% ethanol (1 min), household bleach with a final sodium hypochlorite concentration of 2% (3 min), and washing with sterile distilled water (2 min). The sterilised fragments were placed on Petri plates containing potato dextrose agar (PDA, Difco, USA) plus chloramphenicol at 100 mg/mL. The plates were incubated up to 60 days, and individual fungal isolates were purified on PDA plates. The isolates were stored at 4°C in PDA tubes. Mycelial fragments from each isolate were also preserved in 30% glycerol sterile aqueous suspension at –80°C. All fungal isolates were deposited in the Collection of Microorganisms and Cells of the Universidade Federal of Minas Gerais, Brazil under code UFMGCB.
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Can atmospheric water generation be strategic to companies according to the natural resource based view approach

Can atmospheric water generation be strategic to companies according to the natural resource based view approach

39 “green” markets, which allows them to be seen as early movers in these markets building reputation – as they can be the firsts protecting water sources through an environmental technology while producing, protecting environment, reducing businesses’ negative environmental impacts, such as, health problems, diseases and avoiding water resources depletion; to have preferred access to important sources, for instance, locations (locations with more humidity are preferred as they allow AWG units to produce more drinking water from the air) or customers – those willing to pay a premium for a green and differentiated product; and to establish some environmental standards and rules, according to specificities of company, which may represent barriers or difficulties to other potential entrants (for example establishing levels of water purity, limits in using water resources, levels of energy consumption in production, as well as, limits in using chemicals and toxics). Moreover, and based on the Natural Resource Based View (Hart, 1995), through competitors’ preemption, the implementation of AWG technology may have a huge impact on startup companies, planning to enter in “green markets”, as they can easily implement, since the beginning, AWG units in their facilities or plants, because they do not have any existing ones.
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Folder IFSul | Inglês 2015 (509 Downloads)

Folder IFSul | Inglês 2015 (509 Downloads)

especially when related to educational themes, with relevant scientific and technological aspects. It is essential to search for experiences abroad, looking for intercultural dialogues, providing a comprehensive global view, exchanging knowledge and encouraging the seek for solidarity and peace.

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Effects of probiotic fermented milk on biofilms, oral microbiota, and enamel

Effects of probiotic fermented milk on biofilms, oral microbiota, and enamel

who evaluated the administration of probiotic lactobacilli in liquids and capsules to determine the role of direct contact of probiotics with the oral tissues. Interestingly, both means of administration signiicantly increased the salivary lactobacillus counts, whereas the mutans streptococci levels were not signiicantly altered. Some studies have indicated that direct contact with oral tissues is not a prerequisite for probiotics to have a Table 1. Mean and standard deviation (SD) of the variables analyzed in the enamel surface.

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Marcia Regina Fantoni Torres

Marcia Regina Fantoni Torres

Giardiasis, an intestinal infection caused by Giardia lamblia, was recently included in the ‘Neglected Diseases Initiative’ by the World Health Organization. Symptomatic patients can develop mild diarrhea up to a severe malabsorption syndrome, and children may show significantly impaired cognitive and physical development. Currently, nitroimidazoles are the main class of antibiotic used to treat giardiasis. Despite the efficacy of these drugs, adverse effects and reported resistance have increased, encouraging studies to identify and develop therapeutic alternatives. In this context, probiotics may represent an attractive option. Probiotics are defined as live microorganisms that, when administered in suitable amounts, confer a health benefit to the host. The use of probiotics in the treatment of parasitosis has been suggested because of its beneficial effects, such as a reduced time of gastrointestinal symptoms and parasite load in animal models and humans. Probiotics have been studied as an alternative treatment for giardiasis. In this review, we evaluated probiotic effectiveness in the treatment and prevention of this disease. Based on the studies examined herein, we conclude that probiotics have a beneficial effect on the modulation of giardiasis.
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Wood Science and Technology

Wood Science and Technology

The present study evaluated the foraging and feeding preferences of Coptotermes gestroi (Blattodea: Rhinotermitidae) in wood from four forest species and Medium Density Fiberboard (MDF) in urban areas of the municipalities of Rio de Janeiro, São Gonçalo and Seropédica, RJ, Brazil. Wooden and MDF stakes were buried in the soil in the presence of C. gestroi foragers, in multiple choice assays, where the stakes remained for 15, 30, 60 and 90 days. The highest occurrence of foragers was in Alcântara 2 (São Gonçalo). In three areas, the stakes presented no foraging at any time during the exposure period. Generally, the longer the exposure period, the greater the occurrence of C. gestroi in the stakes and their loss of mass. The Pinus elliottii stakes had a greater loss of mass caused by C. gestroi, followed by the MDF, suggesting the need for preservative treatment of these materials prior to use.
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Economic evaluation of prebiotics, probiotics and symbiotics in juvenile Nile tilapia

Economic evaluation of prebiotics, probiotics and symbiotics in juvenile Nile tilapia

Intestinal microbial flora is important in fish nutrition, as it may increase the production of digestive enzymes, amino acids, short-chain fatty acids and vitamins, improving the use of nutrients (NAIAK, 2010). An increase in the production of amylase, lipase and protease was seen in tilapia fed diets containing Bacillus subtilis (ESSA et al., 2010), and an increase in the height of the intestinal villi was observed when the fish were fed a diet supplemented with a prebiotic, which can favour the absorption of nutrients (SCHWARZ et al., 2010). These factors may have been responsible for the better apparent feed conversion in fish receiving diets containing prebiotics, probiotics and symbiotics, compared to those which received the control diet, and which in this study resulted in greater weight gain.
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J. Appl. Oral Sci.  vol.26

J. Appl. Oral Sci. vol.26

Objective: The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Material and Methods: Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n=16) or placebo (n=15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. Results: All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no signiicant differences between groups. Conclusions: The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group.
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Gag mutations strongly contribute to HIV-1 resistance to protease inhibitors in highly drug-experienced patients besides compensating for fitness loss.

Gag mutations strongly contribute to HIV-1 resistance to protease inhibitors in highly drug-experienced patients besides compensating for fitness loss.

more dramatic effect of these changes on the resistance phenotype. Furthermore, the effect on RC was far less pronounced than that of the total removal of patient-derived Gag sequences, as seen in XS clones. In VIS13, reversion of A431V from VIS13BS reduced RC by about half, a reduction that was strikingly lower than that seen with VIS13XS. In VIS18, the reversion of A431V from VIS18BS did not significantly change RC, contrasting with the strong reduction in RC seen in VIS18XS. In VIS16, the change in RC produced by reversion of I437V was again marginal, but in this virus, only a small change in RC was seen when comparing the BS and the XS clone. These results show that NC-SP2 mutations are not sufficient to explain the losses of RC that characterize clones with highly mutated PR and RT sequences and in which patient-derived Gag sequences are absent. They suggest that sequence determinants in NC-SP2-P6 outside of the NC-SP2 cleavage site account in part for this phenomenon, confirming the published results of Myint et al. [19]. Remarkably, however, when NC-SP2 cleavage site mutations were introduced in the XS clones, in which all Gag sequences are derived from NL4-3, we observed almost complete restoration of RC back to levels measured in BS clones. This surprising result shows that in viruses having evolved under prolonged selective pressure by PIs, RC is dependent upon complex interactions between NC-SP2
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