| 1. |
|
|
| 2. |
- Zuberbier, T., et al.
(författare)
-
Proposal of 0.5 mg of protein/100 g of processed food as threshold for voluntary declaration of food allergen traces in processed food-A first step in an initiative to better inform patients and avoid fatal allergic reactions: A GA(2)LEN position paper
- 2022
-
Ingår i: Allergy. - : Wiley. - 0105-4538 .- 1398-9995. ; 77:6, s. 1736-1750
-
Tidskriftsartikel (refereegranskat)abstract
- Background Food anaphylaxis is commonly elicited by unintentional ingestion of foods containing the allergen above the tolerance threshold level of the individual. While labeling the 14 main allergens used as ingredients in food products is mandatory in the EU, there is no legal definition of declaring potential contaminants. Precautionary allergen labeling such as "may contain traces of" is often used. However, this is unsatisfactory for consumers as they get no information if the contamination is below their personal threshold. In discussions with the food industry and technologists, it was suggested to use a voluntary declaration indicating that all declared contaminants are below a threshold of 0.5 mg protein per 100 g of food. This concentration is known to be below the threshold of most patients, and it can be technically guaranteed in most food production. However, it was also important to assess that in case of accidental ingestion of contaminants below this threshold by highly allergic patients, no fatal anaphylactic reaction could occur. Therefore, we performed a systematic review to assess whether a fatal reaction to 5mg of protein or less has been reported, assuming that a maximum portion size of 1kg of a processed food exceeds any meal and thus gives a sufficient safety margin. Methods MEDLINE and EMBASE were searched until 24 January 2021 for provocation studies and case reports in which one of the 14 major food allergens was reported to elicit fatal or life-threatening anaphylactic reactions and assessed if these occurred below the ingestion of 5mg of protein. A Delphi process was performed to obtain an expert consensus on the results. Results In the 210 studies included, in our search, no reports of fatal anaphylactic reactions reported below 5 mg protein ingested were identified. However, in provocation studies and case reports, severe reactions below 5 mg were reported for the following allergens: eggs, fish, lupin, milk, nuts, peanuts, soy, and sesame seeds. Conclusion Based on the literature studied for this review, it can be stated that cross-contamination of the 14 major food allergens below 0.5 mg/100 g is likely not to endanger most food allergic patients when a standard portion of food is consumed. We propose to use the statement "this product contains the named allergens in the list of ingredients, it may contain traces of other contaminations (to be named, e.g. nut) at concentrations less than 0.5 mg per 100 g of this product" for a voluntary declaration on processed food packages. This level of avoidance of cross-contaminations can be achieved technically for most processed foods, and the statement would be a clear and helpful message to the consumers. However, it is clearly acknowledged that a voluntary declaration is only a first step to a legally binding solution. For this, further research on threshold levels is encouraged.
|
|
| 3. |
- Baranska, S., et al.
(författare)
-
Regulation of the switch from early to late bacteriophage lambda DNA replication
- 2001
-
Ingår i: Microbiology. - : Microbiology Society. - 1350-0872 .- 1465-2080. ; 147, s. 535-547
-
Tidskriftsartikel (refereegranskat)abstract
- There are two modes of bacteriophage lambda DNA replication following infection of its host, Escherichia coli. Early after infection, replication occurs according to the theta (theta or circle-to-circle) mode, and is later switched to the sigma (sigma or rolling-circle) mode. It is not known how this switch, occurring at a specific time in the infection cycle, is regulated. Here it is demonstrated that in type cells the replication starting from ori lambda proceeds both bidirectionally and unidirectionally, whereas in bacteria devoid of a functional DnaA protein, replication from ori lambda is predominantly unidirectional. The regulation of directionality of replication from ori lambda is mediated by positive control of lambda p(R) promoter activity by DnaA, since the mode of replication of an artificial lambda replicon bearing the p(tet) promoter instead of p(R) was found to be independent of DnaA function. These findings and results of density-shift experiments suggest that in dnaA mutants infected with lambda, phage DNA replication proceeds predominantly according to the unidirectional theta mechanism and is switched early after infection to the sigma mode. It is proposed that in wild-type E. coli cells infected with lambda, phage DNA replication proceeds according to a bidirectional theta mechanism early after infection due to efficient transcriptional activation of ori lambda, stimulated by the host DnaA protein. After a few rounds of this type of replication, the resulting increased copy number of lambda genomic DNA may cause a depletion of free DnaA protein because of its interaction with the multiple DnaA-binding sites in lambda DNA. It is proposed that this may lead to inefficient transcriptional activation of ori lambda resulting in unidirectional theta replication followed by sigma type replication.
|
|
| 4. |
|
|
| 5. |
- Dramburg, S, et al.
(författare)
-
EAACI Molecular Allergology User's Guide 2.0
- 2023
-
Ingår i: Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology. - 1399-3038. ; 3434 Suppl 28, s. e13854-
-
Tidskriftsartikel (refereegranskat)
|
|
| 6. |
- Gabig-Ciminska, Magdalena, et al.
(författare)
-
Electric chips for rapid detection and quantification of nucleic acids
- 2004
-
Ingår i: Biosensors & bioelectronics. - : Elsevier BV. - 0956-5663 .- 1873-4235. ; 19:6, s. 537-546
-
Tidskriftsartikel (refereegranskat)abstract
- A silicon chip-based electric detector coupled to bead-based sandwich hybridization (BBSH) is presented as an approach to perform rapid analysis of specific nucleic acids. A microfluidic platform incorporating paramagnetic beads with immobilized capture probes is used for the biorecognition steps. The protocol involves simultaneous sandwich hybridization of a single-stranded nucleic acid target with the capture probe on the beads and with a detection probe in the reaction solution, followed by enzyme labeling of the detection probe, enzymatic reaction, and finally, potentiometric measurement of the enzyme product at the chip surface. Anti-DIG-alkaline phosphatase conjugate was used for the enzyme labeling of the DIG-labeled detection probe. p-Aminophenol phosphate (pAPP) was used as a substrate. The enzyme reaction product, p-aminophenol (pAP), is oxidized at the anode of the chip to quinoneimine that is reduced back to pAP at the cathode. The cycling oxidation and reduction of these compounds result in a current producing a characteristic signal that can be related to the concentration of the analyte. The performance of the different steps in the assay was characterized using in vitro synthesized RNA oligonucleotides and then the instrument was used for analysis of 16S rRNA in Escherichia coli extract. The assay time depends on the sensitivity required. Artificial RNA target and 16S rRNA, in amounts ranging from 10(11) to 10(10) molecules, were assayed within 25 min and 4 h, respectively.
|
|
| 7. |
- Wegrzyn, A., et al.
(författare)
-
ClpP/ClpX-mediated degradation of the bacteriophage lambda O protein and regulation of lambda phage and lambda plasmid replication
- 2000
-
Ingår i: Archives of Microbiology. - : Springer Science and Business Media LLC. - 0302-8933 .- 1432-072X. ; 174:02-jan, s. 89-96
-
Tidskriftsartikel (refereegranskat)abstract
- The O protein is a replication initiator that binds to the ori lambda region and promotes assembly of the bacteriophage lambda replication complex. This protein, although protected from proteases by other elements of the replication complex, in a free form is rapidly degraded in the host, Escherichia coil, by the ClpP/ClpX protease. Nevertheless, the physiological role of this rapid degradation remains unclear. Here we demonstrate that the copy number of plasmids derived from bacteriophage lambda is significantly higher in wild-type cells growing in rich media than in slowly growing bacteria. However, lambda plasmid copy number in bacteria devoid of the ClpP/ClpX protease was not dependent on the bacterial growth rate and in all minimal media rested was comparable to that observed in wildtype cells growing in a rich medium. Contrary to lambda plasmid replication, the efficiency of lytic growth of bacteriophage lambda was found to be dependent on the host growth rate in both wild-type bacteria and clpP and clpX mutants. The activities of two major lambda promoters operating during the lytic development, p(R) and p(L), were found to be slightly dependent on the host growth rate. However, when p(R) activity was significantly decreased in the dnaA mutant, production of phage progeny was completely abolished at low growth rates. These results indicate that the O protein (whose level in E. coli cells depends on the activity of ClpP/ClpX protease) is a major limiting factor in the regulation of lambda plasmid replication at low bacterial growth rates. However, this protein seems to be only one of the limiting factors in the bacteriophage lambda lytic development under poor growth conditions of host cells. Therefore, it seems that the role of the rapid ClpP/ClpX-mediated proteolysis of the O protein is to decrease the efficiency of early DNA replication of the phage in slowly growing host cells.
|
|
| 8. |
- Gabig-Ciminska, Magdalena, et al.
(författare)
-
An introduction to DNA chips : principles, technology, applications and analysis
- 2001
-
Ingår i: Acta Biochimica Polonica. - : Polskie Towarzystwo Biochemiczne (Polish Biochemical Society). - 0001-527X .- 1734-154X. ; 48:3, s. 615-622
-
Forskningsöversikt (refereegranskat)abstract
- This review describes the recently developed GeneChip technology that provides efficient access to genetic information using miniaturised, high-density arrays of DNA or oligonucleotide probes. Such microarrays are powerful tools to study the molecular basis of interactions on a scale that would lie impossible using conventional analysis. The recent development of the microarray technology has greatly accelerated the investigation of gene regulation. Arrays are mostly used to identify which genes are turned on or off in a cell or tissue, and also, to evaluate the extent of a gene's expression under various conditions. Indeed, this technology has been successfully applied to investigate simultaneous expression of many thousands of genes and to the detection of mutations or polymorphisms, as well as for their mapping and sequencing.
|
|
| 9. |
- Gabig-Ciminska, Magdalena, et al.
(författare)
-
Detection of bacteriophage infection and prophage induction in bacterial cultures by means of electric DNA chips
- 2004
-
Ingår i: Analytical Biochemistry. - : Elsevier BV. - 0003-2697 .- 1096-0309. ; 324:1, s. 84-91
-
Tidskriftsartikel (refereegranskat)abstract
- Infections of bacterial cultures by bacteriophages are common and serious problems in many biotechnological laboratories and factories. A method for specific, quantitative, and quick detection of phage contamination, based on the use of electric DNA chip is described here. Different phages of Escherichia coli and Bacillus subtilis were analyzed. Phage DNA was isolated from bacterial culture samples and detected by combination of bead-based sandwich hybridization with enzyme-labeled probes and detection of the enzymatic product using silicon chips. The assay resulted in specific signals from all four tested phages without significant background. Although high sensitivity was achieved in 4h assay time, a useful level of sensitivity (10(7)-10(8) phages) is achievable within 25 min. A multiplex DNA chip technique involving a mixture of probes allows for detection of various types of phages in one sample.. These analyses confirmed the specificity of the assay.
|
|
| 10. |
- Gabig-Ciminska, Magdalena, et al.
(författare)
-
The cell surface protein Ag43 facilitates phage infection of Escherichia coli in the presence of bile salts and carbohydrates
- 2002
-
Ingår i: Microbiology. - : Microbiology Society. - 1350-0872 .- 1465-2080. ; 148, s. 1533-1542
-
Tidskriftsartikel (refereegranskat)abstract
- it was found that infection of Escherichia coli by bacteriophage lambda is inhibited in the presence of certain bile salts and carbohydrates when cells are in the 'OFF' state for production of the phase-variable cell surface protein antigen 43 (Ag43). The inhibition of phage growth was found to be due to a significant impairment in the process of phage adsorption. Expression of the gene encoding Ag43 (agn43) from a plasmid or inactivation of the oxyR gene (encoding an activator of genes important for defence against oxidative stress) suppressed this inhibition. A mutation, rpoA341, in the gene encoding the alpha subunit of RNA polymerase also facilitated phage adsorption in the presence of bile salts and carbohydrates. The rpoA341 mutation promoted efficient production of Ag43 in a genetic background that would otherwise be in the 'OFF' phase for expression of the agn43 gene. Analysis of a reporter gene fusion demonstrated that the promoter for the agn43 gene was more active in the rpoA341 mutant than in the otherwise isogenic rpoA(+) strain. The combined inhibitory action of bile salts and carbohydrates on phage adsorption and the abolition of this inhibition by production of Ag43 was not restricted to lambda as a similar phenomenon was observed for the coliphages P1 and T4.
|
|
