scholarly journals Enumeration Procedure for Monitoring Test Microbe Populations on Inoculated Carriers in AOAC Use-Dilution Methods

2006 ◽  
Vol 89 (6) ◽  
pp. 1629-1634 ◽  
Author(s):  
Stephen F Tomasino ◽  
Rebecca M Fiumara ◽  
Michele P Cottrill
Keyword(s):  
Environmental Protection Agency ◽  
Performance Standard ◽  
Dilution Method ◽  
Bacterial Cells ◽  
Mean Values ◽  
Test Culture ◽  
Monitoring Test ◽  
Aoac Method ◽  
Test Microbe

Abstract The AOAC Use-Dilution methods do not provide procedures to enumerate the test microbe on stainless steel carriers (penicylinders) or guidance on the expected target populations of the test microbe (i.e., a performance standard). This report describes the procedures used by the U.S. Environmental Protection Agency to enumerate the test microbe (carrier counts) associated with conducting the Use-Dilution method with Staphylococcus aureus (Method 955.15) and Pseudomonas aeruginosa (Method 964.02) and the examination of historical data. The carrier count procedure involves the random selection of carriers, shearing bacterial cells from the carrier surface through sonication, and plating of serially diluted inoculum on trypticase soy agar. For each Use-Dilution test conducted, the official AOAC method was strictly followed for carrier preparation, culture initiation, test culture preparation, and carrier inoculation steps. Carrier count data from 78 Use-Dilution tests conducted over a 6-year period were compiled and analyzed. A mean carrier count of 6.6 logs (approximately 4.0 × 106colony-forming units/carrier) was calculated for both S. aureus and P. aeruginosa. Of the mean values, 95% fell within ±2 repeatability standard deviations. The enumeration procedure and target carrier counts are desirable for standardizing the Use-Dilution methods, increasing their reproducibility, and ensuring the quality of the data.

scholarly journals Performance of the AOAC Use-Dilution Method with Targeted Modifications: Collaborative Study

2012 ◽  
Vol 95 (6) ◽  
pp. 1618-1628 ◽  
Author(s):  
Stephen F Tomasino ◽  
Albert E Parker ◽  
Martin A Hamilton ◽  
Gordon C Hamilton
Keyword(s):  
Environmental Protection Agency ◽  
Horse Serum ◽  
Collaborative Study ◽  
Current Method ◽  
Hard Water ◽  
Test Method ◽  
Performance Standard ◽  
Dilution Method ◽  
Modified Method ◽  
Test Culture

Abstract The U.S. Environmental Protection Agency (EPA), in collaboration with an industry work group, spearheaded a collaborative study designed to further enhance the AOAC use-dilution method (UDM). Based on feedback from laboratories that routinely conduct the UDM, improvements to the test culture preparation steps were prioritized. A set of modifications, largely based on culturing the test microbes on agar as specified in the AOAC hard surface carrier test method, were evaluated in a five-laboratory trial. The modifications targeted the preparation of the Pseudomonas aeruginosa test culture due to the difficulty in separating the pellicle from the broth in the current UDM. The proposed modifications (i.e., the modified UDM) were compared to the current UDM methodology for P. aeruginosa and Staphylococcus aureus. Salmonella choleraesuis was not included in the study. The goal was to determine if the modifications reduced method variability. Three efficacy response variables were statistically analyzed: the number of positive carriers, the log reduction, and the pass/fail outcome. The scope of the collaborative study was limited to testing one liquid disinfectant (an EPA-registered quaternary ammonium product) at two levels of presumed product efficacies, high and low. Test conditions included use of 400 ppm hard water as the product diluent and a 5% organic soil load (horse serum) added to the inoculum. Unfortunately, the study failed to support the adoption of the major modification (use of an agar-based approach to grow the test cultures) based on an analysis of method's variability. The repeatability and reproducibility standard deviations for the modified method were equal to or greater than those for the current method across the various test variables. However, the authors propose retaining the frozen stock preparation step of the modified method, and based on the statistical equivalency of the control log densities, support its adoption as a procedural change to the current UDM. The current UDM displayed acceptable responsiveness to changes in product efficacy; acceptable repeatability across multiple tests in each laboratory for the control counts and log reductions; and acceptable reproducibility across multiple laboratories for the control log density values and log reductions. Although the data do not support the adoption of all modifications, the UDM collaborative study data are valuable for assessing sources of method variability and a reassessment of the performance standard for the UDM.

Evaluation of Penicylinders Used in Disinfectant Testing: Bacterial Attachment and Surface Texture

1987 ◽  
Vol 70 (5) ◽  
pp. 903-906
Author(s):  
Eugene C Cole ◽  
William A Rutala ◽  
Johnny L Carson
Keyword(s):  
Stainless Steel ◽  
Surface Texture ◽  
Environmental Protection Agency ◽  
Bacterial Attachment ◽  
Dilution Method ◽  
Bacterial Inoculation ◽  
Protection Agency ◽  
Smooth Numbers ◽  
Salmonella Choleraesuis ◽  
Aoac Method

Abstract Two passible deficiencies in the AOAC use-dilution method for registration of chemical disinfectants by the Environmental Protection Agency are examined: (7) the physical disparities among brands of penicylinders and (2) the variability of bacterial numbers on penicylinders depending upon test strain and penicylinder surface texture. Textual differences of 2 brands of stainless steel penicylinders, one brand of porcelain, and one brand of glass were assessed by scanning electron microscopy. A considerable variation in smoothness of both inner and outer surfaces of stainless steel and porcelain penicylinders was observed. Glass penicylinders were very smooth. Numbers of bacteria attached to a penicylinder were assessed by vortexing the penicylinders 30 s at No. 4 after using the AOAC method of bacterial inoculation and drying 40 min at 37°C. With this methodology, stainless steel carriers retained the 3 AOAC-recommended bacterial test strains differentially: ca 107 for Pseudomonas aeruginosa, 5 x 106 tat Staphylococcus aureus, and 106 for Salmonella choleraesuis; glass retained 10'-107 organisms of all 3 test strains; porcelain retained about that amount of S. aureus but 105-106 P. aeruginosa and 103-104 S. choleraesuis. These data suggest that disinfectants are not similarly challenged with the AOAC-recommended test bacteria and that an alternative method should be considered to ensure comparable numbers of bacteria on penicylinders

scholarly journals The Quality of Statistical Reporting and Data Presentation in Predatory Dental Journals Was Lower Than in Non-Predatory Journals

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 468
Author(s):  
Pentti Nieminen ◽  
Sergio E. Uribe
Keyword(s):  
Open Access ◽  
Peer Review ◽  
Scientific Journals ◽  
Mean Values ◽  
Data Presentation ◽  
Predatory Journals ◽  
Study Results ◽  
The Mean ◽  
Highly Cited

Proper peer review and quality of published articles are often regarded as signs of reliable scientific journals. The aim of this study was to compare whether the quality of statistical reporting and data presentation differs among articles published in ‘predatory dental journals’ and in other dental journals. We evaluated 50 articles published in ‘predatory open access (OA) journals’ and 100 clinical trials published in legitimate dental journals between 2019 and 2020. The quality of statistical reporting and data presentation of each paper was assessed on a scale from 0 (poor) to 10 (high). The mean (SD) quality score of the statistical reporting and data presentation was 2.5 (1.4) for the predatory OA journals, 4.8 (1.8) for the legitimate OA journals, and 5.6 (1.8) for the more visible dental journals. The mean values differed significantly (p < 0.001). The quality of statistical reporting of clinical studies published in predatory journals was found to be lower than in open access and highly cited journals. This difference in quality is a wake-up call to consume study results critically. Poor statistical reporting indicates wider general lower quality in publications where the authors and journals are less likely to be critiqued by peer review.

scholarly journals Enhanced Arsenic Accumulation in Engineered Bacterial Cells Expressing ArsR

2004 ◽  
Vol 70 (8) ◽  
pp. 4582-4587 ◽  
Author(s):  
Jan Kostal ◽  
Rosanna Yang ◽  
Cindy H. Wu ◽  
Ashok Mulchandani ◽  
Wilfred Chen
Keyword(s):  
Cell Growth ◽  
Environmental Protection Agency ◽  
Arsenic Removal ◽  
Fusion Partner ◽  
Resting Cells ◽  
Bacterial Cells ◽  
High Affinity ◽  
Affinity Ligand ◽  
Arsenic Accumulation ◽  
Severe Reduction

ABSTRACT The metalloregulatory protein ArsR, which offers high affinity and selectivity toward arsenite, was overexpressed in Escherichia coli in an attempt to increase the bioaccumulation of arsenic. Overproduction of ArsR resulted in elevated levels of arsenite bioaccumulation but also a severe reduction in cell growth. Incorporation of an elastin-like polypeptide as the fusion partner to ArsR (ELP153AR) improved cell growth by twofold without compromising the ability to accumulate arsenite. Resting cells overexpressing ELP153AR accumulated 5- and 60-fold-higher levels of arsenate and arsenite than control cells without ArsR overexpression. Conversely, no significant improvement in Cd2+ or Zn2+ accumulation was observed, validating the specificity of ArsR. The high affinity of ArsR allowed 100% removal of 50 ppb of arsenite from contaminated water with these engineered cells, providing a technology useful to comply with the newly approved U.S. Environmental Protection Agency limit of 10 ppb. These results open up the possibility of using cells overexpressing ArsR as an inexpensive, high-affinity ligand for arsenic removal from contaminated drinking and ground water.

scholarly journals AB0101 THE IMPACT OF TIME SPAN TO ACHIEVE BOOLEAN REMISSION FOR MAINTAINING DISEASE ACTIVITY AFTER ACQUISITION IN RHEUMATOID ARTHRITIS PATIENT

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii
Keyword(s):  
Rheumatoid Arthritis ◽  
Disease Activity ◽  
Disease Duration ◽  
Remission Rate ◽  
Mean Value ◽  
Time Span ◽  
Mean Values ◽  
The Mean ◽  
The Relationship

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared

Quality of Antenatal, Labour and Delivery Services in Selected Districts in Malawi, Zambia and Zimbabwe: A Descriptive Cross-Sectional Study

2021 ◽  
pp. 1-9
Author(s):  
Clara Opha Haruzivishe
Keyword(s):  
Perinatal Care ◽  
Neonatal Morbidity ◽  
Health Facilities ◽  
Sub Saharan Africa ◽  
Morbidity And Mortality ◽  
World Health ◽  
Performance Standard ◽  
Cross Sectional ◽  
Care Services

Background: High Maternal and Neonatal Mortality Ratios persist in Sub-Saharan Africa despite increasing perinatal care coverage. This suggests that coverage alone is not adequate to reduce maternal and neonatal morbidity and mortality. Quality of care should be the emphasis of maternal and child care services. Materials and Methods: A descriptive cross-sectional multicentre study was conducted in selected health facilities in Zambia, Malawi and Zimbabwe using purposive sampling. A World Health Organization-WHO 2016 Quality of Maternal and New-born assessment Framework and the WHO (2015) Service Availability and Readiness Assessment tool were used for data collection. Data was analyzed using Statistical Package for Social Scientist (SPSS) version 24.0. Results: Less than 43% of the health facilities satisfied at least three of the five Performance Standards of availability and adequacy of Antenatal infrastructure and supplies. Regarding Antenatal processes/care, an observation was the most common performance standard satisfied by 70.6% of all health facilities assessed while less than 30% fulfilled all other standards. Only 57.1% of the health facilities satisfied 5 of the 11 standards for labour and delivery infrastructure, while only 55.6% of the Health facilities satisfied only two of the 13 standards of Labour and delivery care. Conclusion: To achieve a significant and sustainable reduction in maternal and neonatal morbidity and mortality, there is a need for investment and improvement in maternity care services infrastructure and processes as opposed to focusing on mere attendance of Antenatal, and deliveries by trained birth attendants.

Microbial Quality of Ground Beef after Simulated Freezer Failure

1981 ◽  
Vol 44 (1) ◽  
pp. 62-65 ◽  
Author(s):  
FATIMA S. ALI ◽  
FRANCES O. VANDUYNE
Keyword(s):  
Clostridium Perfringens ◽  
Microbial Quality ◽  
Ground Meat ◽  
Frozen Foods ◽  
Mean Values ◽  
Power Failure ◽  
Order Of Magnitude ◽  
Plate Counts ◽  
Coagulase Positive Staphylococci

Six lots of ground meat, obtained at intervals from a local supermarket, were frozen, and later held with other frozen foods in the freezer compartment of a refrigerator-freezer where power failure was simulated by unplugging the unit. Mean values for the counts (log10) of the beef as purchased were as follows: aerobic and psychrotrophic plate counts 6.35 and 6.66, respectively; presumptive coliforms 4.48; coagulase-positive staphylococci 4.67; and presumptive Clostridium perfringens 1.43. Presumptive salmonellae were detected in three of the six lots. Counts of the same order of magnitude as above were obtained after 7 days in the freezers, complete defrost of the meat and 6 h thereafter. Between 6 and 24 h, aerobic and psychrotrophic plate counts and numbers of coliforms and coagulase-positive staphylococci increased approximately 10-fold. Forty-eight hours after complete defrost, further increases in counts occurred. The appearance and aroma of the meat were acceptable 24 h after defrost; after 48 h, it would have been discarded because of browning, slime and off-odors.

scholarly journals Quality of life in a sample of Brazilian adults using the generic SF-12 questionnaire

2018 ◽  
Vol 64 (3) ◽  
pp. 234-242 ◽  
Author(s):  
Alessandro Gonçalves Campolina ◽  
Rossana Veronica Mendoza Lopez ◽  
Elene Paltrinieri Nardi ◽  
Marcos Bosi Ferraz
Keyword(s):  
Quality Of Life ◽  
Skin Color ◽  
Short Form ◽  
Mean Value ◽  
Life Assessment ◽  
Future Research ◽  
Mean Values ◽  
Socio Demographic Factors ◽  
Assess Quality

Summary Objective: This study describes the summary scores of the Short Form-12 (SF-12) questionnaire, according to socio-demographic factors obtained in a probabilistic and representative sample of the Brazilian urban population. Method: Five thousand (5,000) individuals, over the age of 15, were assessed in 16 capital cities, in the five regions of the country. The selection of households was random. Face-to-face approach was applied in the household interviews. The SF-12 questionnaire was used to assess quality of life. Demographic and socioeconomic characteristics were also evaluated: gender, age, marital status, skin color, region of the country and use of the public health service. Results: The mean value (SD) of the SF-12 for the entire population was 49.3 (8.7) for the physical component (PCS-12) and 52.7 (9.7) for the mental component (MCS-12). Statistical differences were found for gender (PCS-12 and MCS-12), age (PCS-12) and working status (PCS-12 and MCS-12). Women, elderly, widowed and unemployed individuals, those with lower income and with complaints in the last seven days showed lower mean values (PCS-12 and MCS-12). Conclusion: From this point forward, we can provide the basis for comparisons with future research that use the SF-12 for quality of life assessment in Brazil. The Brazilian population has a lower degree of quality of life related do the physical component, and the SF-12 is a useful and discriminative instrument for assessing quality of life in different socio-demographic groups.

Genetic engineering: possibilities and prospects for its application in industrial microbiology

1980 ◽  
Vol 290 (1040) ◽  
pp. 369-386 ◽  
Keyword(s):  
Escherichia Coli ◽  
Genetic Engineering ◽  
Detailed Analysis ◽  
Bacterial Cells ◽  
Bacterial Enzymes ◽  
Distant Future ◽  
Cells In Culture ◽  
Wide Range ◽  
Hybrid Dna

A wide range of techniques is now available for the construction of hybrid DNA molecules comprising components from disparate species. Transfer of segments of DNA from other organisms, and especially eukaryotes, to Escherichia coli permits their preparation in quantities sufficient for detailed analysis of their structure and mechanism of expression. This information could be exploited to enhance the quantity or quality of polypeptide products from bacterial cells. Greatly increased yields of bacterial enzymes have been obtained in this way in several instances. The approaches that have been pioneered with bacteria are currently being applied to higher organisms. Much work is in progress with yeasts, in which transformation has been successfully demonstrated, with animal viruses and cells in culture and with some plant systems and offers the promise of wider applications of genetic engineering in the not too distant future.

scholarly journals pH of exudate test in the physiological quality of crambe seeds

2016 ◽  
Vol 46 (6) ◽  
pp. 1014-1018 ◽  
Author(s):  
Charline Zaratin Alves ◽  
Lennis Afraire Rodrigues ◽  
Carlos Henrique Queiroz Rego ◽  
Josué Bispo da Silva
Keyword(s):  
Pearson Correlation ◽  
Raw Material ◽  
Mean Values ◽  
Tukey Test ◽  
Physiological Quality ◽  
The Subject ◽  
The Mean ◽  
C 30

ABSTRACT: Crambe is a rapeseed with high oil content and can be used as a winter cover or as a source of raw material for the production of biodiesel, however espite the growing interest in the culture, research on the subject is still incipient, especially concerning the seed production and analysis technology. The purpose of this study is to evaluate the physiological quality of crambe seeds, 'FMS Brilhante' cultivar, by testing the pH of exudate. Five seed lots were submitted to the determination of water content and the tests of germination and vigor (first count, emergence and tetrazolium). In the conduction of pH exudate test, temperatures (25 and 30oC), and periods of seed imbibition in water (15, 30 and 45 minutes) were tested. The experiment was conducted in a completely randomized manner, with four replicates, and the mean values were compared by the Tukey test at 5% probability; Pearson correlation between the pH of the exudate and initial tests was also made. Testing the pH of exudate is promising for separating lots of crambe seeds and the following combinations of 25°C/30 minutes or 30°C/45 minutes can be used.

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