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1.
Vaccine ; 42(6): 1300-1310, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38302336

ABSTRACT

DNA- based vaccines have demonstrated the potential as a safe and effective modality. PlaCCine, a DNA-based vaccine approach described subsequently relies on a synthetic DNA delivery system and is independent of virus or device. The synthetic functionalized polymer combined with DNA demonstrated stability over 12 months at 4C and for one month at 25C. Transfection efficiency compared to naked DNA increased by 5-15-fold in murine skeletal muscle. Studies of DNA vaccines expressing spike proteins from variants D614G (pVAC15), Delta (pVAC16), or a D614G + Delta combination (pVAC17) were conducted. Mice immunized intramuscular injection (IM) with pVAC15, pVAC16 or pVAC17 formulated with functionalized polymer and adjuvant resulted in induction of spike-specific humoral and cellular responses. Antibody responses were observed after one immunization. And endpoint IgG titers increased to greater than 1x 105 two weeks after the second injection. Neutralizing antibodies as determined by a pseudovirus competition assay were observed following vaccination with pVAC15, pVAC16 or pVAC17. Spike specific T cell immune responses were also observed following vaccination and flow cytometry analysis demonstrated the cellular immune responses included both CD4 and CD8 spike specific T cells. The immune responses in vaccinated mice were maintained for up to 14 months after vaccination. In an immunization and challenge study of K18 hACE2 transgenic mice pVAC15, pVAC16 and pVAC17 induced immune responses lead to decreased lung viral loads by greater than 90 % along with improved clinical score. These findings suggest that PlaCCine DNA vaccines are effective and stable and further development against emerging SARS-CoV-2 variants is warranted.


Subject(s)
COVID-19 , Vaccines, DNA , Mice , Animals , COVID-19 Vaccines , COVID-19/prevention & control , SARS-CoV-2 , Mice, Transgenic , Antibodies, Neutralizing , DNA , Antibodies, Viral , Spike Glycoprotein, Coronavirus/genetics , Immunogenicity, Vaccine
2.
J Biol Chem ; 298(9): 102377, 2022 09.
Article in English | MEDLINE | ID: mdl-35970388

ABSTRACT

Biosynthesis of riboflavin (RF), the precursor of the redox cofactors FMN and FAD, was thought to be well understood in bacteria, with all the pathway enzymes presumed to be known and essential. Our previous research has challenged this view by showing that, in the bacterium Sinorhizobium meliloti, deletion of the ribBA gene encoding the enzyme that catalyzes the initial steps on the RF biosynthesis pathway only causes a reduction in flavin secretion rather than RF auxotrophy. This finding led us to hypothesize that RibBA participates in the biosynthesis of flavins destined for secretion, whereas S. meliloti has another enzyme that performs this function for internal cellular metabolism. Here, we identify and biochemically characterize a novel formamidase (SMc02977) involved in the production of RF for intracellular functions in S. meliloti. This catalyst, which we named Sm-BrbF, releases formate from the early RF precursor 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate to yield 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate. We show that homologs of this enzyme are present in many bacteria, are highly abundant in the Rhizobiales order, and that sequence homologs from Brucella abortus and Liberobacter solanacearum complement the RF auxotrophy of the Sm1021ΔSMc02977 mutant. Furthermore, we show that the B. abortus enzyme (Bab2_0247, Ba-BrbF) is also an 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate formamidase, and that the bab2_0247 mutant is a RF auxotroph exhibiting a lower level of intracellular infection than the wildtype strain. Finally, we show that Sm-BrbF and Ba-BrbF directly interact with other RF biosynthesis pathway enzymes. Together, our results provide novel insight into the intricacies of RF biosynthesis in bacteria.


Subject(s)
Amidohydrolases , Riboflavin , Sinorhizobium meliloti , Amidohydrolases/metabolism , Flavin Mononucleotide , Flavin-Adenine Dinucleotide , Formates , Phosphates , Riboflavin/biosynthesis , Sinorhizobium meliloti/enzymology
3.
Nutrients ; 14(12)2022 Jun 12.
Article in English | MEDLINE | ID: mdl-35745167

ABSTRACT

The use of mobile applications for dietary purposes has dramatically increased along with the consistent development of mobile technology. Assessing diet quality as a dietary pattern or an indicator across key food groups in comparison to those recommended by dietary guidelines is useful for identifying optimal nutrient intake. This systematic review aims to explore mobile applications and their impact on the diet quality of the user. The electronic databases of The Cumulative Index to Nursing and Allied Health Literature (Cinahl), The American Psychological Association's (APA Psycinfo), and PubMed were systematically searched for randomised and non-randomised controlled trials to retrieve papers from inception to November 2021. Ten studies with 1638 participants were included. A total of 5342 studies were retrieved from the database searches, with 10 articles eligible for final inclusion in the review. The sample sizes ranged from 27 to 732 participants across the included studies, with 1638 total participants. The ratio of female to male participants in the studies was 4:1. The majority of the mobile applications or M-health interventions were used to highlight dietary health changes (six studies), with the remainder used to reduce weight or blood sugar levels (four studies). Each study used a different measure to quantify diet quality. Studies were either assessed by diet quality scoring or individual dietary assessment, of the ten studies, six studies reported an improvement in diet quality following diet-related mobile application use. Mobile applications may be an effective way to improve diet quality in adults; however, there is a need for more targeted and longer-term studies that are expressly designed to investigate the impact using mobile applications has on diet quality.


Subject(s)
Mobile Applications , Telemedicine , Adult , Biomedical Technology , Diet , Female , Humans , Male , Technology
4.
Physiother Theory Pract ; 38(12): 2019-2028, 2022 Dec.
Article in English | MEDLINE | ID: mdl-33706647

ABSTRACT

BACKGROUND AND PURPOSE: Outcome measures (OMs) have been emphasized by healthcare professions to optimize patient examination; however, a lack of regular use of OMs exists. The purpose of this study was to describe the outcome of a knowledge translation (KT) intervention to increase the use of OMs by physical therapists in an inpatient rehabilitation setting. METHODS: A quasi-experimental pre-post study design was used. A multi-component KT intervention including education, organizational support, documentation, and environmental changes to increase the use of five OMs was implemented. Audit and feedback (A&F) was added to the KT intervention at month 6. Documented use of OMs was determined through manual chart audit (n = 864) and electronically (n = 2599). Regression analyses were used to identify factors associated with OMs use across time and diagnoses. RESULTS: Following the addition of A&F to the KT intervention at month 6, there was a significant increase in the odds of OMs use across all time intervals (months 6-12, 12-18, 18-24)(Odds Ratio (OR) 5.9, 95% Confidence Interval (CI) 4.1-8.5; OR 8.5, 95% CI 6.0-12.1; OR 10.8, 95% CI 7.6-15). There was also a significant increase in the odds of documenting OMs on individuals with neurological diagnoses (OR 0.3, 95% CI 0.5-0.8). CONCLUSIONS: This KT intervention increased and sustained OMs use over 24-months. This intervention can be replicated to improve the evidence-based practices of physical therapists.


Subject(s)
Physical Therapists , Humans , Inpatients , Translational Science, Biomedical , Translational Research, Biomedical , Outcome Assessment, Health Care
5.
Mol Plant Microbe Interact ; 34(12): 1409-1422, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34402628

ABSTRACT

Using tandem mass spectrometry (MS/MS), we analyzed the proteome of Sinorhizobium medicae WSM419 growing as free-living cells and in symbiosis with Medicago truncatula. In all, 3,215 proteins were identified, over half of the open reading frames predicted from the genomic sequence. The abundance of 1,361 proteins displayed strong lifestyle bias. In total, 1,131 proteins had similar levels in bacteroids and free-living cells, and the low levels of 723 proteins prevented statistically significant assignments. Nitrogenase subunits comprised approximately 12% of quantified bacteroid proteins. Other major bacteroid proteins included symbiosis-specific cytochromes and FixABCX, which transfer electrons to nitrogenase. Bacteroids had normal levels of proteins involved in amino acid biosynthesis, glycolysis or gluconeogenesis, and the pentose phosphate pathway; however, several amino acid degradation pathways were repressed. This suggests that bacteroids maintain a relatively independent anabolic metabolism. Tricarboxylic acid cycle proteins were highly expressed in bacteroids and no other catabolic pathway emerged as an obvious candidate to supply energy and reductant to nitrogen fixation. Bacterial stress response proteins were induced in bacteroids. Many WSM419 proteins that are not encoded in S. meliloti Rm1021 were detected, and understanding the functions of these proteins might clarify why S. medicae WSM419 forms a more effective symbiosis with M. truncatula than S. meliloti Rm1021.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Subject(s)
Medicago truncatula , Sinorhizobium meliloti , Nitrogen , Nitrogen Fixation , Proteome , Root Nodules, Plant , Sinorhizobium , Symbiosis , Tandem Mass Spectrometry
7.
Health Mark Q ; 37(2): 124-137, 2020.
Article in English | MEDLINE | ID: mdl-32319872

ABSTRACT

There has been dramatic weight gain among college students during their collegiate years. A food diary can give much insight of a college student's life. The purpose of this study is to analyze the food intake of college-aged students taking in factors such as the size of meal, the foods being eaten, the location of the meal, and if the meal was eaten with others. The results of this study suggest that being male, eating breakfast, and eating more snacks relative to the number meals increases daily caloric intake. On the other hand, being female and eating more meals at home will result in a lower daily caloric intake.


Subject(s)
Diaries as Topic , Energy Intake/physiology , Feeding Behavior/psychology , Independent Living , Adult , Female , Humans , Male , Sex Factors , Snacks/psychology , Students/psychology , Universities , Young Adult
8.
Nurse Pract ; 45(4): 34-41, 2020 04.
Article in English | MEDLINE | ID: mdl-32205673

ABSTRACT

Gaps in care currently exist between diabetic kidney disease (DKD) guidelines and diabetes management in primary care settings. Implementation of quality improvement (QI) initiatives often improves these gaps in care. This article outlines a QI initiative exploring whether a local Federally Qualified Health Center could improve rates of screening for microalbuminuria, diagnosis of DKD, and treatment of the disorder in patients with type 2 diabetes mellitus.


Subject(s)
Diabetes Mellitus, Type 2/therapy , Diabetic Nephropathies/diagnosis , Mass Screening , Primary Health Care , Quality Improvement/organization & administration , Albuminuria/diagnosis , Diabetes Mellitus, Type 2/complications , Humans , Practice Guidelines as Topic
9.
Am J Med Genet A ; 182(5): 962-973, 2020 05.
Article in English | MEDLINE | ID: mdl-32031333

ABSTRACT

CDC42BPB encodes MRCKß (myotonic dystrophy-related Cdc42-binding kinase beta), a serine/threonine protein kinase, and a downstream effector of CDC42, which has recently been associated with Takenouchi-Kosaki syndrome, an autosomal dominant neurodevelopmental disorder. We identified 12 heterozygous predicted deleterious variants in CDC42BPB (9 missense, 2 frameshift, and 1 nonsense) in 14 unrelated individuals (confirmed de novo in 11/14) with neurodevelopmental disorders including developmental delay/intellectual disability, autism, hypotonia, and structural brain abnormalities including cerebellar vermis hypoplasia and agenesis/hypoplasia of the corpus callosum. The frameshift and nonsense variants in CDC42BPB are expected to be gene-disrupting and lead to haploinsufficiency via nonsense-mediated decay. All missense variants are located in highly conserved and functionally important protein domains/regions: 3 are found in the protein kinase domain, 2 are in the citron homology domain, and 4 in a 20-amino acid sequence between 2 coiled-coil regions, 2 of which are recurrent. Future studies will help to delineate the natural history and to elucidate the underlying biological mechanisms of the missense variants leading to the neurodevelopmental and behavioral phenotypes.


Subject(s)
Developmental Disabilities/genetics , Intellectual Disability/genetics , Myotonin-Protein Kinase/genetics , Neurodevelopmental Disorders/genetics , Adolescent , Adult , Amino Acid Sequence , Autistic Disorder/epidemiology , Autistic Disorder/genetics , Autistic Disorder/pathology , Child , Child, Preschool , Developmental Disabilities/epidemiology , Developmental Disabilities/pathology , Female , Frameshift Mutation , Haploinsufficiency , Heterozygote , Humans , Infant , Infant, Newborn , Intellectual Disability/epidemiology , Intellectual Disability/pathology , Loss of Function Mutation/genetics , Male , Mutation, Missense/genetics , Neurodevelopmental Disorders/epidemiology , Neurodevelopmental Disorders/pathology , Phenotype
10.
J Food Prot ; 82(12): 2119-2125, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31729916

ABSTRACT

A chemiluminescence assay using a handheld luminometer to measure the activity of alkaline phosphatase was developed that can detect 0.002% or more of unpasteurized milk in various milk products. Evaluation of the assay followed an National Conference on Interstate Milk Shipments (NCIMS)-approved protocol in which aliquots of pasteurized milk products were spiked with raw milk at various levels. Milk products evaluated included skim white milk, 1 and 2% fat content white milk, whole white milk, strawberry-flavored 1% fat content milk, chocolate-flavored 1% fat content milk, half-and-half, and heavy cream. Split samples were prepared, and alkaline phosphatase activities were determined in triplicate on 4 days by three NCIMS-accredited laboratories by the chemiluminescent method and NCIMS-approved reference methods. Equivalence of the chemiluminescent method to the approved reference methods was demonstrated for all eight products evaluated over a range of raw milk concentration from 0 to 0.5%, using criteria established by NCIMS, in which mean results obtained by the three laboratories by the chemiluminescent method were within 1 standard deviation of the mean results obtained by the NCIMS-approved reference methods at each alkaline phosphatase concentration. Procedures for measurement of microbial and reactivated alkaline phosphatase were also established for the method.


Subject(s)
Alkaline Phosphatase , Food Microbiology , Luminescent Measurements , Milk , Pasteurization , Alkaline Phosphatase/metabolism , Animals , Food Microbiology/methods , Luminescence , Luminescent Measurements/instrumentation , Milk/standards , Pasteurization/standards
11.
J AOAC Int ; 101(6): 1813-1827, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29776460

ABSTRACT

A validation study was conducted for an immunochromatographic method (BetaStar® Advanced for Beta-lactams) for the detection of beta-lactam residues in raw, commingled bovine milk. The assay detected amoxicillin, ampicillin, cloxacillin, penicillin, cephapirin, and ceftiofur below the U.S. Food and Drug Administration tolerance levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. The results of internal and independent laboratory dose-response studies employing spiked samples were in agreement. The test detected all six drugs at the approximate 90/95% sensitivity levels in milk from cows treated with each drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing 1148 control milk samples. Testing the estimated 90/95% sensitivity level for amoxicillin (8.5 ppb), ampicillin (6.9 ppb), cloxacillin (8.9 ppb), penicillin (4.2 ppb), and cephapirin (17.6 ppb), and at 100 ppb for each antibiotic, resulted in 94-100% positive tests for each of the beta-lactam drugs. The results of ruggedness experiments established the operating parameter tolerances for the assay. Cross-reactivity testing established that the assay detects other certain beta-lactam drugs, but it does not cross-react with any of 30 drugs belonging to seven different drug classes. Abnormally high bacterial or somatic cell counts in raw milk produced no assay interference.


Subject(s)
Anti-Bacterial Agents/analysis , Chromatography, Affinity/methods , Drug Residues/analysis , Food Contamination/analysis , Milk/chemistry , beta-Lactams/analysis , Animals , Anti-Bacterial Agents/immunology , Cross Reactions , Penicillins/analysis , Penicillins/immunology , beta-Lactams/immunology
12.
J AOAC Int ; 101(6): 1794-1805, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29743134

ABSTRACT

A validation study was conducted for an immunochromatographic method (BetaStar® Advanced for Tetracyclines) for detection of tetracycline antibiotic residues in raw, commingled bovine milk. The assay was demonstrated to detect tetracycline, chlortetracycline, and oxytetracycline at levels below the FDA tolerance levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. Results of internal and independent laboratory dose-response studies employing spiked samples were in agreement. All three drugs at the approximate 90/95% sensitivity levels were detected in milk collected from cows that had been treated with the specific drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing 881 control milk samples. Testing the estimated 90/95 sensitivity level for tetracycline (213 ppb), chlortetracycline (272 ppb), and oxytetracycline (180 ppb) and at 1000 ppb for each antibiotic resulted in 100% positive tests for each tetracycline. Results of ruggedness experiments established the operating parameter tolerances for the test. Results of cross-reactivity testing established that the assay detects certain other tetracycline drugs but does not cross-react with any of 32 drugs belonging to seven different drug classes. Abnormally high bacterial or somatic cell counts (SCC) in raw milk produced no assay interference.


Subject(s)
Anti-Bacterial Agents/analysis , Chromatography, Affinity/methods , Drug Residues/analysis , Food Contamination/analysis , Milk/chemistry , Tetracyclines/analysis , Animals , Anti-Bacterial Agents/immunology , Chlortetracycline/analysis , Chlortetracycline/immunology , Cross Reactions , Oxytetracycline/analysis , Oxytetracycline/immunology , Tetracycline/analysis , Tetracycline/immunology , Tetracyclines/immunology
13.
Asia Pac J Public Health ; 30(1): 56-66, 2018 01.
Article in English | MEDLINE | ID: mdl-29302988

ABSTRACT

China successfully achieved universal health insurance coverage in 2011. Previous work on the effects of social health insurance in China has overlooked the association between health insurance and inpatient service category as well as the mechanisms of institutional characteristics. This study seeks to estimate the social health insurance difference in inpatient expenditure and service category. The role of institutional characteristics was also studied. The logistic model was applied to estimate the association of social health insurance and service category. In addition, Heckman Selected Model and generalized linear model were used to examine the association of health insurance and inpatient expenditure. Estimations were done for 4076 individuals older than 45 years using pooled cross-sectional survey data from the China Health and Retirement Longitudinal Study conducted in 2011 and 2013. Patients with health insurance were more likely to spend more and receive more types of inpatient service. This relationship was partially explained by the institutional characteristics. Therefore, this study highlights the importance of enforcing the regulation of referral mechanisms, the tiered copayment requirement to guide people's care-seeking behavior, and reforming the allocation of limited health resources between different levels of facilities and also between private and public hospitals.


Subject(s)
Health Expenditures/statistics & numerical data , Hospitalization/economics , Hospitalization/statistics & numerical data , National Health Programs/economics , China , Cross-Sectional Studies , Female , Humans , Male , Middle Aged
14.
J AOAC Int ; 101(1): 118-123, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-29202917

ABSTRACT

Neogen Corp. has developed Veratox for Almond Allergen for use in the quantitative analysis and screening of almond protein residues in food products, such as cookies, crackers, chocolate bars, cereals, beverages, and clean-in-place rinses. Quantitation with Veratox for Almond Allergen ranges from 2.5 to 25 ppm and, with dilution, it can be extended for highly positive samples. This paper describes the findings of internal testing and validation studies designed to establish product claims for the assay of Veratox for Almond Allergen.


Subject(s)
Allergens/analysis , Enzyme-Linked Immunosorbent Assay , Food Analysis , Prunus dulcis/chemistry , Humans
15.
J AOAC Int ; 100(4): 1131-1133, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28421981

ABSTRACT

Neogen Corp. (Lansing, MI) has developed a common aqueous extraction method for the detection of mycotoxins in the ELISA or lateral flow format. The Veratox® for Total Aflatoxin ELISA extraction method uses a MAX 2 extraction packet and water in replacement of traditionally used organic solvents. Veratox for Total Aflatoxin has a detection range of 5-50 ppb neat or up to 300 ppb with dilution. The kit development focused on superior cross-reactivity, ability to accurately detect naturally contaminated samples, and utilization of an aqueous extraction method. In two separate validation studies, the Veratox for Total Aflatoxin test kit resulted in average yields of 91-114% in naturally contaminated mycotoxin reference material corn. The cross-reactivity profiles for aflatoxins B1, B2, G1, and G2 were 100, 113, 103, and 93%, respectively. This kit is approved by the Grain Inspection, Packers, and Stockyards Administration.


Subject(s)
Aflatoxins/analysis , Food Analysis/methods , Liquid-Liquid Extraction/methods , Enzyme-Linked Immunosorbent Assay , Zea mays/chemistry
16.
J AOAC Int ; 100(2): 537-547, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28118134

ABSTRACT

The AccuPoint Advanced ATP Hygeine Monitoring System was validated by an AOAC International Performance Tested MethodSM on the detection of ATP from stainless steel surfaces. Neogen Corp.'s system is a lightweight, hand-held diagnostic tool used to validate and verify a hygiene program's effectiveness by detecting organic residues remaining on surfaces and in liquids after cleaning. The system is composed of three primary components: an electronic luminometer, fully self-contained single-use samplers, and software. The system is designed to detect adenosine triphosphate (ATP) at set thresholds and to report the measurement in relative light units (RLU). These thresholds are established by a facility to reflect effective cleaning practices. The instrument compares the measured level of ATP with the established threshold and reports the results as pass, marginal, or fail. A linear dose-response in RLU was observed with pure analyte. In the matrix and microbial studies, detection levels varied depending on the matrix and microorganism tested. Independent laboratory trials confirmed pure analyte and matrix observations. Specificity testing of similar, yet different, compounds resulted in 0 RLU for all except 2'-deoxyadenosine 5'-triphosphate sodium salt, which showed markedly reduced reactivity when compared with ATP. Also, interference by these compounds was negligible. When disinfectant residues were evaluated for their effect on the test, cleaners increased RLU output to varying degrees. Stability testing showed consistent results between three independently manufactured lots and stable results through the 9 month shelf-life. Additionally, when three readers were compared using electronic light-emitting diodes as the light source, instrument variability was low (<3%). Robustness testing results provided evidence that temperature affects test performance more than shaking time, and sampler performance improves as the temperature increases to room temperature. These results provided evidence that the AccuPoint Advanced ATP Hygiene Monitoring System produces consistent and reliable data for the evaluation of sanitation program effectiveness on stainless steel surfaces in food processing and food service facilities.


Subject(s)
Adenosine Triphosphate/analysis , Stainless Steel/analysis , Benzalkonium Compounds/chemistry , Decanoic Acids/chemistry , Fatty Acids/chemistry , Hygiene , Limit of Detection , Luciferases/chemistry , Luminescent Measurements , Pseudomonas aeruginosa/isolation & purification , Saccharomyces cerevisiae/isolation & purification , Sanitation , Sodium Hypochlorite/chemistry , Staphylococcus aureus/isolation & purification
17.
J AOAC Int ; 99(6): 1555-1564, 2016 Nov 01.
Article in English | MEDLINE | ID: mdl-27634328

ABSTRACT

A performance validation of the ANSR® for Campylobacter method was conducted in selected matrixes. This assay used selective nicking enzyme amplification technology to amplify target genes. Samples were enriched for 20 to 24 h and then lysed. The assay was completed within 50 min using real-time detection in a combination incubator/fluorescence detector and software. When 50 distinct strains of Campylobacter jejuni, C. lari, or C. coli were tested for inclusivity, all 50 strains produced positive results. In exclusivity testing, 31 strains of related organisms, including seven nontarget Campylobacter strains and other common species, were evaluated. All 31 species generated negative ANSR assay results, including the nontarget Campylobacter strains. The ANSR for Campylobacter method was compared to the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference method using naturally contaminated chicken carcass rinse or turkey carcass sponge samples. ANSR method performance was not statistically different from the reference method using two different enrichment options. Equivalent results were observed at both time points (20 and 24 h) and in both atmospheres (microaerobic and aerobic) to reference methods. Method performance with chicken carcass rinse was confirmed in an independent laboratory study. Additionally, in robustness testing, small, deliberate changes to the assay parameters minimally affected ANSR method performance. Finally, accelerated stability results from three independently manufactured lots supported a shelf life of 6 months when stored at 4°C. The ANSR assay offered greater efficiency and flexibility when compared to the reference method with a 20-24 h single-step enrichment in a microaerobic or an aerobic atmosphere.


Subject(s)
Campylobacter/isolation & purification , Meat/microbiology , Temperature , Animals , Chickens/microbiology , Software , Spectrometry, Fluorescence , Turkeys/microbiology
18.
J AOAC Int ; 99(3): 705-16, 2016 May.
Article in English | MEDLINE | ID: mdl-27297839

ABSTRACT

A performance validation of the ANSR(®) for E. coli O157:H7 method was conducted in selected food matrixes. This assay uses selective nicking enzyme amplification technology to amplify target genes. Samples are enriched for 12-24 h and then lysed. The assay is completed within 40 min using real-time detection in a combination incubator/fluorescence detector and software. When 44 distinct strains of Escherichia coli O157:H7 and 6 strains of E. coli O157:NM were tested for inclusivity, all 50 strains produced positive results. In exclusivity testing, 57 strains representing 33 species of closely related Gram-negative bacteria belonging to the Enterobacteriaceae family, including 11 non-H7 O157 strains and shiga toxin-producing E. coli other than O157:H7, were evaluated. All 57 nontarget strains generated negative ANSR assay results. Using 80% lean ground beef and beef trim (approximately 20% fat), ANSR method performance was compared to the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedure. ANSR performance with baby spinach and sprout irrigation water was measured against the U.S. Food and Drug Administration Bacteriological Analytical Manual reference method. ANSR method performance was not statistically different to that of the reference methods using two different enrichment options. For ground beef and beef trim, the standard enrichment in modified Tryptone Soya Broth can be analyzed using the ANSR assay with a 1:10 dilution of the enrichment in phosphate-buffered saline and produces equivalent results to the reference method. Additionally, in most matrixes tested (exception is spinach which required 24 h enrichment) the assay offers great efficiency and flexibility over the reference method with a 12-24 h single-step enrichment. Equivalent results were observed at both time points (12 and 24 h) to reference methods. Small changes to the assay parameters minimally affected ANSR method performance. Finally, accelerated stability results from three independently manufactured lots support a shelf-life of 6 months when stored at 4°C.


Subject(s)
Bacteriological Techniques , Escherichia coli O157/isolation & purification , Software , Spectrometry, Fluorescence
19.
J AOAC Int ; 99(4): 1017-1024, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27214854

ABSTRACT

A study was conducted to assess the performance of the Reveal(®) 2.0 Group D1 Salmonella lateral flow immunoassay for use in detection of Salmonella Enteritidis (SE) in raw shell eggs and poultry-associated matrixes, including chicken carcass rinse and poultry feed. In inclusivity testing, the Reveal 2.0 test detected all 37 strains of SE tested. The test also detected all but one of 18 non-Enteritidis somatic group D1 Salmonella serovars examined. In exclusivity testing, none of 42 strains tested was detected. The exclusivity panel included Salmonella strains of somatic groups other than D1, as well as strains of other genera of Gram-negative bacteria. In matrix testing, performance of the Reveal 2.0 test was compared to that of the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedure for chicken carcass rinse and to that of the U.S. Food and Drug Administration Bacteriological Analytical Manual for raw shell eggs and poultry feed. For all matrixes evaluated, there were no significant differences in the ability to detect SE when comparing the Reveal 2.0 method and the appropriate reference culture procedure as determined by probability of detection statistical analysis. The ability of the Reveal 2.0 test to withstand modest perturbations to normal operating parameters was examined in robustness experiments. Results showed that the test can withstand deviations in up to three operating parameters simultaneously without significantly affecting performance. Real-time stability testing of multiple lots of Reveal 2.0 devices established the shelf life of the test device at 16 months postmanufacture.


Subject(s)
Eggs/microbiology , Immunoassay , Salmonella enteritidis/isolation & purification , Animals , Food Microbiology , Poultry
20.
J AOAC Int ; 99(1): 98-111, 2016.
Article in English | MEDLINE | ID: mdl-27053468

ABSTRACT

A study was conducted to validate minor reagent formulation, enrichment, and procedural changes to the ANSR(®) Listeria method, Performance-Tested Method(SM) 101202. In order to improve ease of use and diminish risk of amplicon contamination, the lyophilized reagent components were reformulated for increased solubility, thus eliminating the need to mix by pipetting. In the alternative procedure, an aliquot of the lysate is added to lyophilized ANSR reagents, immediately capped, and briefly mixed by vortexing. When three foods (hot dogs, Mexican-style cheese, and cantaloupe) and sponge samples taken from a stainless steel surface were tested, significant differences in performance between the ANSR and U.S. Food and Drug Administration Bacteriological Analytical Manual or U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedures were seen with hot dogs and Mexican-style cheese after 16 h enrichment, with the reference methods producing more positive results. After 24 h enrichment, however, there were no significant differences in method performance for any of the four matrixes tested. Robustness testing was also conducted, with variations to lysis buffer volume, lysis time, and sample volume having no demonstrable effect on assay results. Accelerated stability testing was carried out over a 10-week period and showed no diminishment in assay performance. A second phase of the study examined performance of the ANSR assay following enrichment in a new medium, LESS Plus broth, designed for use with all food and environmental sample types. With the alternative LESS Plus broth, there were no significant differences in performance between the ANSR method and the reference culture procedures for any of the matrixes tested after either 16 or 24 h enrichment, although 24 h enrichment is recommended for hot dogs due to higher sensitivity. Results of inclusivity and exclusivity testing using LESS Plus broth showed that the ANSR assay is highly specific, with 100% expected results for target and nontarget bacteria.


Subject(s)
Bacteriological Techniques , Food Analysis , Food Microbiology , Listeria/isolation & purification , Reagent Kits, Diagnostic , United States
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