hygiena KIT230110 Foodproof Clostridium Botulinum Detection LyoKit Instructions
- June 22, 2024
- Hygiena
Table of Contents
hygiena KIT230110 Foodproof Clostridium Botulinum Detection LyoKit
Specifications
- Product Name: foodproof C. botulinum Detection LyoKit
- Product No.: KIT230110 (LP), KIT230111 (RP)
- Detection: Botulinum type A, B, E, and F neurotoxin-producing Clostridium strains
- Intended Use: For food testing purposes
- Storage: Keep lyophilized PCR Mix away from light and moisture
Product Usage Instructions:
What this Product Does
This kit is designed for the qualitative detection of botulinum type A, B,
E, and F neurotoxin-producing Clostridium strains using real-time PCR
instruments.
Number of Tests
The kit contains components for 96 reactions.
Storage and Stability
Store the lyophilized PCR Mix away from light and moisture.
Kit Contents
The kit includes LyoKit strips specific for DNA of botulinum neurotoxin
types A, B, E, and F, control template, PCR-grade water, and cap strips.
Additional Equipment and Reagents Required
Additional equipment includes SR-32 rotor or Vortex centrifuge CVP-2 for
PCR plates.
Applicability Statement
Intended for the qualitative detection of botulinum strains isolated from
enrichment cultures prepared by valid methods.
How to Use this Product
Before You Begin
Precautions
- Perform under nuclease-free conditions to avoid contamination.
- Keep the lyophilized PCR Mix away from light and moisture.
Sample Material
Use sample material suitable for PCR in terms of purity and absence of
inhibitors. Prepare genomic DNA according to package insert instructions.
FAQ
-
Q: Can the kit be used for diagnostic procedures?
A: No, the kit must not be used in diagnostic procedures; it is intended for food testing purposes only. -
Q: Are additional reagents required for the PCR process?
A: The kit provides all reagents required for the PCR process. Additional equipment like a centrifuge may be needed.
foodproof® Clostridium botulinum Detection LyoKit
Revision A, December 2023
PCR kit for the qualitative detection of botulinum type A, B, E and F
neurotoxin-producing Clostridium strains (Clostridium botulinum, C. baratii
and C. butyricum) using real-time PCR instruments.
Product No. KIT230110 (LP), KIT230111 (RP)
Kit for 96 reactions (lyophilized) for a maximum of 94 samples
Store the kit at 2 to 8 °C
For food testing purposes
FOR IN VITRO USE ONLY
What this Product Does
Number of Tests
The kit is designed for 96 reactions with a final reaction volume of 25 µL
each. Up to 94 samples (single sample preparation) plus positive and negative
control reactions can be analyzed per run.
Storage and Stability
- Store the kit at 2 to 8 °C through the expiration date printed on the label.
- Once the kit is opened, store the kit components as described in the following Kit Contents table:
Kit Contents
Component | Label | Contents / Function / Storage |
---|
foodproof® Clostridium botulinum Detection LyoKit
Microplate, prefilled with 96 reactions (lyophilized)
| Aluminum bag containing an 8-tube strip format
- KIT230110 with white low-profile tubes*
- KIT230111 with clear regular profile tubes*
|
- 96 prefilled reactions (lyophilized).
- Ready-to-use PCR mix containing primer and probes specific for DNA of the botulinum neurotoxin types A, B, E and F and the Internal Control (IC) as well as Taq DNA Polymerase and Uracil-N-Glycosylase (UNG, heat-labile) for prevention of carry-over contamination.
- For amplification and detection of botulinum neurotoxin type A, B, E and F specific sequences.
- Store at 2 to 8 °C in the aluminum bag (sealed).
- Protect from light and moisture!
Control Template| Vial 2 (purple cap)|
- 1 x 250 µL
- Contains a stabilized solution of DNA.
- For use as a PCR run positive control.
- Store at 2 to 8 °C.
H2O PCR-grade| Vial 3 (colorless cap)|
- 2 x 1 mL
- Nuclease-free, PCR-grade H2O.
- For use as a PCR run negative control.
- Store at 2 to 8 °C.
Cap strips| Plastic bag containing 8-cap strips|
- 12 x 8-cap strip
- For use in real-time PCR after addition of samples.
*Tube profile and instrument compatibility chart is available online: www.hygiena.com/document-library 1.4 Additional Equipment and Reagents Required
- Real-time PCR cycler suitable for detection of FAM-, HEX-, and ROX- labeled probes and capable of performing a melting curve analysis. Without a melting curve analysis, the four botulinum neurotoxin types can still be detected but not differentiated. In case the strip tubes don´t fit the instrument, the samples have to be transferred to appropriate PCR vessels after resuspension of the lyophilized PCR mix.
- Sample Preparation Kit
- foodproof StarPrep® Two Kit (Product No.: KIT230177)
- Resuspension Reagent (Product No. Kit230010)
- Sterile double-distilled water
- Nuclease-free, aerosol-resistant pipette tips
- Pipettors
- Vortex centrifuge Multispin MSC-6000 for PCR strips with
- SR-32, Rotor for MSC-3000/6000 or
- Vortex centrifuge CVP-2 for PCR plates
Applicability Statement
The foodproof Clostridium botulinum Detection LyoKit is intended for the
qualitative detection of botulinum type A, B, E and F neurotoxin-producing
Clostridium strains (Clostridium botulinum, C. baratii and C. butyricum)
isolated from enrichment cultures prepared by valid methods and inoculated
with all relevant kinds of samples that are potentially contaminated with
these microorganisms.
The kit must not be used in diagnostic procedures.
The kit described in this Instruction Manual has been developed for real-time
PCR instruments with FAM, HEX, and ROX detection channels which are capable of
performing a melting curve analysis. The performance of the kit was tested
with the following real-time PCR instruments: LightCycler® 480, LightCycler 96
(Roche Diagnostics), Mx3005P® (Agilent Technologies), ABI 7500 Fast (Applied
Biosystems), iQ5 (Bio-Rad), and PikoReal® 24 (Thermo Scientific).
Note: A Color Compensation (Color Compensation Set 3 – Product No.:
KIT230005) is necessary and will be supplied by Hygiena Diagnostics GmbH for
users of the LC 480 Systems. Please contact us for further information.
How to Use this Product
Before You Begin
Precautions
Detection of DNA using the foodproof Clostridium botulinum Detection LyoKit
requires DNA amplification by PCR. The kit provides all reagents required for
the PCR. However, in order to achieve reliable results, the entire assay
procedure must be performed under nuclease-free conditions. Follow the
instructions below to avoid nuclease-, carry-over-, or cross-contamination:
- Keep the kit components separate from other reagents in the laboratory.
- Use nuclease-free labware (e.g., pipettors, pipette tips, reaction vials).
- Wear gloves when performing the assay.
- To avoid cross-contamination of samples and reagents, use fresh aerosol-preventive pipette tips.
- To avoid carry-over contamination, transfer the required solutions for one experiment into a fresh tube, rather than directly pipetting from stock solutions.
- Physically separate the workplaces for DNA preparation, PCR setup, and PCR to minimize the risk of carry-over contamination. Use a PCR hood for all pipetting steps.
Keep the foodproof Clostridium botulinum Detection lyophilized PCR Mix away from light and moisture.
Sample Material
Use any sample material suitable for PCR in terms of purity, concentration,
and absence of inhibitors. For preparation of genomic DNA from various sample
enrichments, refer to the corresponding product package inserts of a suitable
sample preparation kit (see “Additional Equipment and Reagents Required”).
-
DNA Extraction
Hygiena Diagnostics GmbH provides sample preparation kits suitable for all kind of food samples and PPS (see “Additional Equipment and Reagents Required”).
For more product information please refer to www.hygiena.com. -
Positive Control
Always run a positive control with the samples. To prepare a positive control, replace the template DNA with the provided control DNA [foodproof Clostridium botulinum Detection Control Template (vial 2, purple cap)] or with a positive sample preparation control. -
Negative Control
Always run a negative control with the samples. To prepare a negative control, replace the template DNA with PCR-grade water (vial 3, colorless cap). Include a negative control during sample preparation to monitor reaction purity and cross-contamination. This extraction control can be used as an additional negative control reaction.
Procedure
- Program Setup
The following procedure is optimized for a real-time PCR instrument with a FAM (amplification of the botulinum neurotoxin types BoNT A and E, melting curve identification of BoNT E), HEX (amplification of BoNT B and F, melting curve identification of BoNT F), and ROX (amplification of the Internal Control) detection channel. Program the PCR instrument before preparing the PCR samples. Use the following real-time PCR protocol for the foodproof Clostridium botulinum Detection LyoKit. For details on how to program the experimental protocol, see the Instrument Operator’s Manual of your real-time PCR cycler:
Pre-incubation
Step 1:
Step 2:
| 1 cycle
37 °C for 4 minutes
95 °C for 5 minutes
---|---
Amplification
Step 1: Step 2*:
| 50 cycles
95 °C for 5 seconds
60 °C for 60 seconds
- Fluorescence detection in step 2
Melting Curve
Step 1:
Step 2: Step 3*:
| 1 cycle
95 °C for 50 seconds
37 °C for 50 seconds Ramp up to 80 °C
- Fluorescence detection during 37 to 80 °C ramp with 1 – 2 measurements/°C
Notes
- For some real-time PCR instruments, the type of the probe quencher as well as the usage of a passive reference dye has to be specified. The foodproof Clostridium botulinum Detection LyoKit contains probes with a non-fluorescent (“dark”) quencher and no passive reference dye.
- For users of the Agilent Mx3005P instrument: Choose Experiment Type ′SYBR® Green (with Dissociation Curve)′ and add FAM, HEX and ROX channels for data collection in the setup section.
- Please contact Hygiena Diagnostics GmbH if you have questions about how to program your cycler.
Preparation of the PCR Mix
Proceed as described below to prepare a 25 µL standard reaction. Always wear
gloves when handling strips or caps. Use any sample material suitable for PCR
in terms of purity, concentration, and absence of inhibitors.
Note: The PCR strips must be stored in the provided aluminum bag with silica
gel pads to avoid liquid absorption.
-
Take the needed number of PCR tube strips out of the aluminum bag. Use scissors or scalpel to cut the strips apart. Tightly seal the bag afterwards and store away at the recommended conditions.
-
Place the PCR tube strips containing the lyophilized reagents in a suitable PCR tube rack. Check that the reagent pellets are at the bottom of the tubes. If not, briefly centrifuge or flick the pellets to the bottom before proceeding.
-
Uncap the tube strips cautiously and discard the cap strips.
Note : Do not leave strips open for extended periods of time. To avoid unwanted liquid absorption, open strips only shortly before filling. -
Pipet 25 µL sample into each PCR vessel:
- For the samples of interest, add 25 µL sample DNA. (if using less volume, add PCR-grade H2O to achieve 25 µL).
- For the negative control, add 25 µL PCR-grade H2O (vial 3, colorless cap).
- For the positive control, add 25 µL foodproof Clostridium botulinum Detection Control Template (vial 2, purple cap).
Note : To reduce the risk of cross-contamination, it is recommended to prepare only one PCR tube strip at a time.
-
Seal the vessels accurately and tightly with the colorless cap strips.
-
Mix thoroughly using a vortex centrifuge.
Note : Hygiena Diagnostics GmbH recommends vortex centrifuges Multispin MSC-3000 for PCR strips or vortex centrifuge CVP-2 for PCR plates. Dedicated protocols are available for this centrifuge.
Note : Alternatively resuspend the pellet by manual mixing. This may be achieved by cautiously pipetting the sample up and down multiple times during step 4 or flipping the tube strips after sealing while pressing down the cap strip. -
Spin the PCR tube strips for 30 seconds at 150 – 200 x g in a suitable centrifuge.
Note : If your centrifuge exceeds 200 x g, do not centrifuge for more than 5 seconds. Avoid centrifugation at forces exceeding 1000 x g! -
Place the samples in your PCR cycler and run the program as described above.
Note : For using any LightCycler 480 instrument, a special adapter is necessary. For some PCR instruments, the PCR strips should be placed in a balanced order into the cycler block. For example, two strips can be placed in column 1 and 12 across from each other.
Data Interpretation
The kit is intended for the qualitative detection of botulinum type A, B, E
and F neurotoxin-producing Clostridium strains (Clostridium botulinum, C.
baratii and C. butyricum).
Amplification
The amplification of botulinum neurotoxin types BoNT A and E is analyzed in
the fluorescence channel suitable for FAM labeled probes detection. The
amplification of BoNT B and F is analyzed in the fluorescence channel suitable
for HEX. The amplification of the Internal Control is analyzed in the
fluorescence channel suitable for ROX.
Compare the results from channels FAM, HEX and ROX for each sample, and
interpret the results as described in the table below.
Channel FAM| Channel HEX| Channel ROX| Result
Interpretation
---|---|---|---
Positive
|
Negative
| Positive or Negative| Positive for BoNT A and/or E Negative for BoNT B and F
Negative
|
Positive
| Positive or Negative| Negative for BoNT A and E Positive for BoNT B and/or F
Positive
|
Positive
| Positive or Negative| Positive for BoNT A and/or E Positive for BoNT B
and/or F
Negative| Negative| Positive| Negative for BoNT A, B, E, F
Negative| Negative| Negative| Invalid
Note: The Control Template contains a mixture of all four target sequences and therefore usually generates significantly higher fluorescent values than samples that are positive for only one or two of the targets. This can affect positive/negative calls in automatic analysis of amplification curves by the respective instrument software. Always check results visually for plausibility.
Melting curves
Samples that show a positive amplification signal in the FAM or HEX detection
channel can be further differentiated using a melting curve analysis in these
channels.
A prerequisite for the unambiguous discrimination of the botulinum neurotoxin
types in this multi-color experiment is a suitable calibration of the PCR
instrument for channels FAM, HEX and ROX. Please refer to your real-time PCR
cycler Operator’s Manual for further information.
The following table lists the detectable botulinum neurotoxin types in the respective channels and their expected melting peak temperatures (± 2 °C dependent on the real-time PCR instrument):
Botulinum neurotoxin type (BoNT)| FAM channel – melting peak
temperature| HEX channel – melting peak temperature
---|---|---
A| none| none
B| none| none
E| 68 °C ± 2 °C| none
F| none| 55 °C ± 2 °C and 64.5 °C ± 2 °C
Control Template| (64 °C ± 2 °C)| 55 °C ± 2 °C and 62.5 °C ± 2 °C
Note: The melting peak temperature ranges in the above table mainly
reflect the variability between instruments and their respective analysis
software. The Control Template contains a mixture of all target sequences, but
its melting peaks are distinguishable from the expected melting peaks of BoNT
E and F samples. However, single sequence variants of BoNT E or F may differ
in their melting peak temperature. Furthermore, food and sample components can
slightly shift melting peak temperatures, and the Control Template peak can be
absent in the FAM channel.
The screenshots show typical melting curves on a LightCycler 480 instrument.
BoNT = Botulinum neurotoxin type
Melting peak temperatures greater than 70 °C can occur but are not attributed to one of the target botulinum neurotoxin types and can safely be ignored.
The peak height of positive samples may vary according to the initial cell concentration. Note that the presence or absence of specific melting peaks should be checked manually for all positive samples as the peak finding algorithms of the respective PCR instrument software may not detect all relevant maxima of the melting curve. A guarantee for the identification via melting curves cannot be given.
3. Troubleshooting
Observation | Possible Reason | Recommendation |
---|---|---|
No signal increase is observed, even with positive controls. | Incorrect | |
detection channel has been chosen. | Set channel settings to the appropriate |
detection channel.
Pipetting errors.|
- Check for correct reaction setup. Repeat the PCR run.
- Always run a positive control along with your samples.
No data acquisition programmed.| Check the cycle programs.
No signal increase in channel ROX is observed.| Inhibitory effects of the
sample material (e.g., caused by insufficient purification).|
- Use the recommended DNA sample preparation kit to purify template DNA.
- Dilute samples or pipet a lower amount of sample DNA (e.g., 5 µL instead of 25 µL).
Fluorescence intensity is too low.| Inappropriate storage of kit components.|
Store the foodproof Clostridium botulinum Detection lyophilized PCR Mix at 2
to 8 °C, protected from light and moisture.
Low initial amount of target DNA.|
- Increase the amount of sample DNA. Depending on the chosen DNA isolation method, inhibitory effects may occur.
Strong decrease of fluorescence baseline.| Resuspension of lyophilized PCR mix not complete.|
- Always resuspend lyophilized PCR mix thoroughly.
Negative control samples are positive.| Carry-over contamination.|
- Exchange all critical solutions.
- Repeat the complete experiment with fresh aliquots of all reagents.
- Always handle samples, kit components and consumables in accordance with commonly accepted practices to prevent carry-over contamination.
Fluorescence intensity varies.| Insufficient centrifugation of the PCR strips.
Resuspended PCR mix is still in the upper part of the vessel.
|
- Always centrifuge PCR strips.
Outer surface of the vessel or the seal is dirty (e.g., by direct skin contact).|
- Always wear gloves when handling the vessels and seal.
Pellets are difficult to dissolve.| The lyophilized PCR mix started to rehydrate.|
- Store the lyophilized PCR mix always in the aluminum bag with the silica gel pad.
- Open strip shortly before filling.
Observation | Possible Reason | Recommendation |
---|---|---|
Amplification positive and melting curve negative, or vice versa. | Low initial | |
amount of target DNA. |
- Prolong the enrichment time and perform a new sample preparation.
- Increase the amount of sample DNA. Depending on the chosen DNA isolation method, inhibitory effects may occur.
Additional Information on this Product
How this Product Works
The foodproof Clostridium botulinum Detection LyoKit provides all necessary
reagents and a Control Template for reliable interpretations of results. To
ensure maximum reliability of the kit and to prevent misinterpretation of
negative results due to inhibition of the amplification, an Internal Control
(IC) is included. A hydrolysis probe was designed to bind specifically the IC,
allowing detection in the ROX channel, whereas the botulinum neurotoxin DNA is
detected in channel FAM and HEX. In case of a negative result due to
inhibition of the amplification by the sample DNA of interest, the
amplification of the IC is suppressed as well, whereas a negative result for
the sample DNA of interest and amplification of the IC clearly indicates the
absence of DNA of the target organisms in the sample. The foodproof
Clostridium botulinum Detection LyoKit minimizes contamination risk and
contains all reagents (except for template DNA) needed for the detection of
DNA of the target botulinum neurotoxin types. Primers and probes provide
specific detection in food samples. The described performance of the kit is
guaranteed for use on the real-time PCR instruments listed above only.
Test Principle
- Using the kit’s sequence-specific primers in a polymerase chain reaction (PCR), the PCR instrument and the supplied reagents amplify fragments of botulinum neurotoxin specific sequences.
- The PCR instrument detects these amplified fragments in real time through fluorescence generated by cleavage of the hybridized probes due to the 5´-nuclease activity of the Taq DNA polymerase.
- During the ramp phase of the PCR (melting curve), additional probes hybridize to an internal sequence of the amplicons which separates the reporter dye from the quencher dye, increasing the reporter dye signal.
- The PCR instrument measures the emitted fluorescence of the reporter dye.
Prevention of Carry-Over Contamination
The heat-labile Uracil-N-Glycosylase (UNG) is suitable for preventing carry-
over contamination between PCRs. This technique relies on the incorporation of
deoxyuridine triphosphate (dUTP) during all amplification reactions, and the
pretreatment of all successive PCR mixtures with the heat-labile UNG. The UNG
cleaves DNA at any site where a deoxyuridine residue has been incorporated.
The resulting abasic sites are hydrolyzed due to the high temperatures during
the initial denaturation step and can no longer serve as PCR templates. The
heat-labile UNG is inactivated during the initial denaturation step. Native
DNA (e.g., the isolated Clostridium genomic DNA) does not contain uracil and
is therefore not degraded by this procedure. Since dTTP is replaced with dUTP
and UNG is included in the foodproof Clostridium botulinum Detection LyoKit,
decontamination can be achieved with the provided reagents.
Background Information
Botulism is a potentially lethal paralytic disease caused by botulinum
neurotoxin, which is the most poisonous naturally occurring substance known
[1]. Different anaerobic, Gram-positive spore-forming Clostridium species
including Clostridium botulinum and some strains of Clostridium baratii and
Clostridium butyricum are able to produce botulinum neurotoxins [2].
Botulism can occur in three forms: food-borne botulism, infant botulism and
wound botulism. Food-borne botulism is the classical form of botulism caused
by the consumption of food containing preformed neurotoxin. Foods most
frequently involved are home-canned foods such as cured meats, canned
vegetables, and fermented fish products. Outbreaks caused by commercial foods
included sausages, sauces, vacuum-packed seafood and other kinds of preserved
or canned food products.
Infant botulism can happen to infants ingesting spores of toxin-producing
clostridia, which are able to germinate and develop in the intestine since
babies younger than one year possess a poorly developed gut microflora. The
bacteria release the toxin into the intestine followed by absorbance of the
toxin into the bloodstream causing paralysis by blocking neuron cells. Honey
and infant milk powder have been associated with infant botulism [4].
Wound botulism is a rare form developing when botulinum toxin producing spores
germinate and grow in profound wounds or abscesses that provide anaerobic
conditions.
The botulinum neurotoxins are classified into eight serotypes designated A–H
[2], [3], of which A, B, E, and F are shown toxic to humans [4].
Identification of botulinum neurotoxin types A, B, E and F with the foodproof
Clostridium botulinum Detection LyoKit is in accordance with ISO/TS 17919 [5].
Not the neurotoxins itself but the neurotoxin genes are detected by the
molecular technique used.
References
- D. M. Gill, “Bacterial toxins: a table of lethal amounts,” Microbiological reviews, vol. 46, no. 1, pp. 86-94, 1982.
- M. D. Collins and A. K. East, “Phylogeny and taxonomy of the food-borne pathogen Clostridium botulinum and its neurotoxins.,” Journal of applied microbiology, vol. 84, no. 1, pp. 5-17, Jan. 1998.
- J. Barash and S. Arnon, “A novel strain of Clostridium botulinum that produces type B and type H botulinum toxins,” The Journal of infectious diseases, vol. 209, no. 2, pp. 183-91, 2014.
- M. Lindström and H. Korkeala, “Laboratory diagnostics of botulism,” Clinical Microbiology Reviews, vol. 19, no. 2, pp. 298-314, 2006.
- ISO/TS17919, “Microbiology of food, animal feed, and environmental samples – Polymerase chain reaction (PCR) for the detection of food-borne pathogens – Detection of botulinum type A, B, E, and F neurotoxin-producing clostridia.” 2012.
Quality Control
The foodproof Clostridium botulinum Detection LyoKit is function-tested using
the LightCycler 480 System and the Mx3005P®.
Supplementary Information
-
Ordering Information
Hygiena Diagnostics GmbH is offering a broad range of reagents and services. For a complete overview and for more information, please visit our website at www.hygiena.com. -
License
License Notice
The purchase price of this product includes limited, nontransferable rights under U.S. Patent No. 7,687,247 owned by Life Technologies Corporation to use only this amount of the product to practice the claims in said patent solely for activities of the purchaser for bioburden testing, environmental testing, food testing, or testing for genetically modified organisms (GMO) in accordance with the instructions for use accompanying this product. No other rights are conveyed, including no right to use this product for in vitro diagnostic, therapeutic, or prophylactic purposes. Further information on purchasing licenses under the above patent may be obtained by contacting the Licensing Department, Life Technologies Corporation, 5791 Van Allen Way, Carlsbad, CA 92008. Email: outlicensing@lifetech.com. -
Trademarks
foodproof® is a registered trademark of Hygiena Diagnostics GmbH. Other brand or product names are trademarks of their respective holders. -
Contact and Support
If you have questions or experience problems with this or any other product of Hygiena Diagnostics GmbH, please contact our Technical Support staff (www.hygiena.com/support). Our scientists commit themselves to providing rapid and effective help. We also want you to contact us if you have suggestions for enhancing our product performance or using our products in new or specialized ways. Such customer information has repeatedly proven invaluable to us and the worldwide research community. -
Reference Number
The reference number and original Hygiena Diagnostics GmbH article number: R 602 40
Change Index
- Version 1, April 2015
- First version of the manual.
- Version 2, June 2016
- Addition of Resuspension Reagent and sterile double-distilled water in Chapter 1 “Additional Equipment and Reagents Required”
- Version 3, March 2017
- License Notice changed.
- Introduction of vortex centrifuges into the PCR Setup Procedure.
- Revision A, December 2023
- Rebranding and new layout.
- R 602 40 20 -> INS-KIT230110-11-REVA
Hygiena®
Camarillo, CA 93012
USA
diagnostics.support@hygiena.com
Manufactured by
Hygiena Diagnostics GmbH Hermannswerder 17
14473 Potsdam
Germany
www.hygiena.com
foodproof C. botulinum Detection LyoKit
INS-KIT2300110-11-REVA
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