INFLUENCE OF PRODUCT TO BE FRIED TYPE ON THE RATE OF THERMAL OXIDATION OF OILS

Проведено исследование процесса термического окисления подсолнечного и кокосового масел при 175°С в условиях поточного обжаривания в них картофеля и куриных наггетсов с отбором проб растительного масла через каждый час работы. Для определения количества продуктов окисления был использован метод спектрофотометрии. Установлено, что после 10 ч проведения обжарки исследованные фритюрные масла были пригодны для дальнейшего использования (Е < 15). Показатель оптической плотности кокосового масла независимо от вида обжариваемого в нем продукта в течение всего эксперимента был ниже аналогичного показателя подсолнечного масла. Предложена оптимальная температура нагрева кокосового масла для обжаривания во фритюре – не более 0,9 от температуры точки дымления. Показано более активное накопление вторичных продуктов окисления во фритюрном масле при обжаривании продукта животного происхождения по сравнению с обжариванием продукта растительного происхождения, что можно объяснить наличием в составе картофеля ингибиторов окисления (пероксидаза, каталаза, витамин С). The study of the process of thermal oxidation of sunflower and coconut oils at 175°C under conditions of in-line frying of potatoes and chicken nuggets in them with the sampling of vegetable oil every hour of operation was carried out. To determine the amount of oxidation products the method of spectrophotometry was used. It was found that after 10 hours of roasting, the studied fryer oils were suitable for further use (E < 15). The optical density index of coconut oil, regardless of the type of product fried in it, was lower than that of sunflower oil throughout the experiment. The optimal heating temperature of coconut oil for deep frying is proposed-no more than 0,9 of the temperature of the smoking point. A more active accumulation of secondary oxidation products in deep-frying oil is shown when frying an animal product compared to frying a vegetable product, which can be explained by the presence of oxidation inhibitors (peroxidase, catalase, vitamin C) in the composition of potatoes.

Performance of Aspergillus Galactomannan Lateral Flow Assay on Bronchoalveolar Lavage Fluid for the Diagnosis of Invasive Pulmonary Aspergillosis

Background: Several newly developed biomarker tests for invasive pulmonary aspergillosis (IPA) have been developed, including the IMMY Aspergillus galactomannan lateral flow assay (Aspergillus GM-LFA) evaluated in this study. Methods: Twenty patients with proven/probable IPA (EORTC/MSGERC criteria) were matched by age and underlying disease with 20 patients without IPA. Bronchoalveolar lavage fluid (BALF) was analyzed in duplicate using the Aspergillus GM-LFA. Results were read visually by two blinded observers, and the optical density index (ODI) was obtained digitally with a cube reader. Results: Using a cutoff of ≥0.5 ODI, the Aspergillus GM-LFA had a sensitivity of 40%, specificity of 80%, positive predictive value (PPV) of 67% and negative predictive value (NPV) of 57%. When the cutoff was increased to ≥1.0 ODI, sensitivity remained at 40%, specificity rose to 95%, PPV was 89%, and NPV was 61%. Excellent agreement was found when duplicate samples were read either visually (κ = 1) or with the cube reader (κ = 0.89). Correlation of results obtained by visual inspection and those obtained using the cube reader was excellent (κ = 0.82). Conclusion: The Aspergillus GM-LFA had poor sensitivity but excellent specificity for proven/probable IPA in BALF. The assay was easy to interpret, and there was high concordance between results obtained visually and with a cube reader.

735. Trends and Cost Analysis of Aspergillus Galactomannan testing at a Tertiary Medical Center

Background Aspergillus is a fungus spread by inhalation of spores that can lead to invasive (IA), chronic, or allergic aspergillosis. Risk factors for IA include neutropenia, hematological malignancy, allogenic stem cell (HSCT) or solid organ transplant, severe immunodeficiency, or prolonged steroid use. An alternative to invasive tissue sampling, the serum Galactomannan (AGM) test detects a polysaccharide cell wall component of Aspergillus and can be used to determine a probable diagnosis of IA. Accuracy of AGM is related to disease burden and thus has the highest sensitivity and specificity in patients with hematologic malignancy or Hematopoietic stem cell transplantation (HSCT) at 70-82% and 86-92%, respectively. Studies have shown sensitivity to decline in other populations, with solid organ transplants as low as 20%. Methods We performed a retrospective study of all patients who received the AGM test at UMMC from January 3, 2013 to December 31, 2019. Patient Cohort Explorer was used to obtain de-identified patient data from EPIC. We obtained the number of encounters and patients on whom the AGM test was performed along with other variables. Billing offices provided the self-pay cost per AGM test. Results A total of 6,404 AGM tests were performed on 2,126 patients during 4,315 encounters in the study period. With a total of 499, 574, 984, 1140, 851, 1175 and 1181 tests done respectively from 2013 to 2019, a increasing trend was noted. The patients ages ranged from 1 to 89 with a median age of 52 years. A total of 3,055 tests were ordered in females, and 3,349 were ordered in males. At a cut off value (optical density index) of &gt; 0.5, 183 AGM tests resulted positive in 108 patients and at a cut of &gt; 1.0, 113 tests are positive in 70 patients. The rate of a positive AGM tests at &gt; 0.5 was at 2.85% and at &gt; 1.0 was at 1.76% over the study period. With the self-pay cost of each test at $134.54 in 2019 USD, the total cost of 6,404 tests was $861,594.16. Conclusion To our knowledge this data set constitutes the largest sample size of AGM testing. From our data, it seems that the rate of ordering this test has increased yearly. Relatively low percentage of these tests are positive, suggesting that it is most likely a large amount of these tests could have been ordered inappropriately or in the wrong clinical context. Disclosures All Authors: No reported disclosures

Optical density of bone tissue in the dynamics of therapy of professionally caused osteopathies of the shoulder joint

Optical density index can be a criterion of bone mineral saturation, both at the stage of primary diagnosis and in the dynamics of observation of patients with shoulder periarthrosis and osteoarthritis of the shoulder joint.

Composition of organic-mineral complexes (OMC) migrating in the reclaimed sod-podzolic soils (Umbric Albeluvisol Abruptic)

The composition of organo-mineral complexes (OMC) migrating from the arable horizon limed by Umbric Albeluvisol Abruptic was studied. The carbon content in organic-mineral complexes (OMC) ranged from 5.5 to 5.7%. The optical density index (Esmg/ml) varied in the range of values from 2.7 to 3.1, characteristic for fulvic acids (FA). It was established that FAs averaged with bases retain the ability to exert a destructive effect on soil minerals, transferring a significant amount of Al, Mn, and Fe into solution. According to their ability to migrate as part of OMC, the elements studied in the experiment with dolomite particles at a dose of 7.35 t/ha were arranged in the following decreasing sequence: Mn > Al > Fe. In the experiment with conversion chalk (CC) at a dose of 20.25 t/ha, this sequence was Al > Mn > Fe.

Morphological and adhesive properties of Klebsiella pneumoniae biofilms

Background and Aim: The study of biofilm-forming ability of Gram-negative microflora has great practical importance for assessing the effectiveness of antibiotic therapy and finding new ways to diagnose and inhibit the growth of biofilms. This is because poor penetration of antibacterial drugs into the biofilm can lead to the selection of resistant strains and has a consequence evident by the occurrence of relapse of infection in animals. This study aimed to evaluate morphological and densitometric indicators of biofilm formation as well as adhesive properties of Klebsiella pneumoniae. Materials and Methods: K. pneumoniae was cultured at 37°C for 2-144 h in vitro. The specimens for optical microscopy were prepared by fixation with a 1:1 alcohol-ether mixture for 10 min and stained with a 0.5% solution of gentian violet for 2 min, and the optical density index was evaluated at a wavelength of 490 nm. Further, the adhesive properties of the microorganisms were determined at a concentration of 1 billion/ml and a suspension of ram erythrocytes at a concentration of 100 million/ml when cultured at 37°C for 24 h. Blood smears were prepared and stained with 0.5% gentian violet. Results: K. pneumonia cultured at 37°C after 24 h on the meat peptone agar formed large, convex, mucous, and white colonies (d=3.0-6.0 mm). With the growth in the meat and peptone broth, uniform turbidity of the medium was observed. Analyzing the optical density indices (density, D), it was found that K. pneumoniae were good producers of biofilms (D=0.528±0.31). Data for indicators of adhesive properties of K. pneumoniae were as follows: Average adhesion index, 4.56±0.14; adhesion coefficient, 1.07±0.52; and adhesion index, 4.26±0.07. The studied bacteria had high adhesive activity. A direct correlation dependence (R=0.94) of the optical density of biofilms (D≥0.514-0.551) and AAI (4.15±0.28-4.76±0.75) was established. Conclusion: This study has demonstrated that K. pneumoniae had high adhesive activity, was strong producer of biofilms, and the optical density of the sample exceeded the optical density of the control by more than 4 times.

Plasmalyte: No Longer a Culprit in Causing False-Positive Galactomannan Test Results

False-positive galactomannan (GM) results have been reported in patients treated with gluconate-containing solutions, such as Plasmalyte. The GM optical density index was tested on 33 distinct batches of Plasmalyte and was found to be negative in all of the batches, confirming that Plasmalyte is no longer a cause of false-positive GM results.

Improved Standardization of the Bio-Rad Platelia Aspergillus Galactomannan Antigen Sandwich Enzyme Immunoassay Using the DS2 (Dynex) Enzyme-Linked Immunosorbent Assay (ELISA) Processing System

The galactomannan enzyme immunoassay (GM-EIA) is widely utilized for the diagnosis of invasive aspergillosis (IA). There is inconsistent reproducibility of results between centers when the assay is processed manually. Automation of EIAs can reduce variation. This study investigated the semiautomation of the GM-EIA on the DS2 (Dynex) platform in the following three stages: (i) DS2 GM-EIA method validation with experimental samples, (ii) DS2 retesting of case-defined clinical samples, and (iii) a 12-month audit of DS2 GM-EIA performance. In stage i, Bland-Altman analysis demonstrated a reduced variance between optical density index (ODI) values for samples processed on two DS2 platforms (mean difference, −0.02; limits of agreement [LOA], −0.19 to 0.14) compared with the variance between samples processed manually and on a DS2 platform (mean difference, 0.02; LOA, −0.25 to 0.3). In stage ii, 100% (14/14 samples) qualitative agreement was observed for serum samples from patients with IA, with no significant change in the ODI values when samples were processed on the DS2 platform. A significant decrease in ODI values was observed for control serum samples on the DS2 platform (difference, 0.01;P= 0.042). In stage iii, a significant reduction in the frequency of equivocal results, from 5.56% (136/2,443 samples) to 1.56% (15/961 samples), was observed after DS2 automation (difference, 4.0%; 95% confidence interval [CI], 2.7 to 5.2%;P< 0.01), with an equivalent increase in negative results. This study demonstrates that GM-EIA automation may reduce intersite variability. Automation does not have an impact on the repeatability of truly positive results but contributes to a reduction in false-positive (equivocal) GM-EIA results, reducing the need to retest a significant proportion of samples.

Seasonal breeding drives the incidence of a chronic bacterial infection in a free-living herbivore population

SUMMARYUnderstanding seasonal changes in age-related incidence of infections can be revealing for disentangling how host heterogeneities affect transmission and how to control the spread of infections between social groups. Seasonal forcing has been well documented in human childhood diseases but the mechanisms responsible for age-related transmission in free-living and socially structured animal populations are still poorly known. Here we studied the seasonal dynamics ofBordetella bronchisepticain a free-living rabbit population over 5 years and discuss the possible mechanisms of infection. This bacterium has been isolated in livestock and wildlife where it causes respiratory infections that rapidly spread between individuals and persist as subclinical infections. Sera were collected from rabbits sampled monthly and examined using an ELISA. Findings revealed thatB. bronchisepticacirculates in the rabbit population with annual prevalence ranging between 88% and 97%. Both seroprevalence and antibody optical density index exhibited 1-year cycles, indicating that disease outbreaks were seasonal and suggesting that long-lasting antibody protection was transient. Intra-annual dynamics showed a strong seasonal signature associated with the recruitment of naive offspring during the breeding period. Infection appeared to be mainly driven by mother-to-litter contacts rather than by interactions with other members of the community. By age 2 months, 65% of the kittens were seropositive.

Incidence of Invasive Aspergillosis in Allogeneic Stem Cell Transplantation Patients: An Italian Prospectic Multicenter Study.

Between January 2003 and June 2004, every consecutive patient admitted for HSCT in three institutions was monitored for circulating galactomannan (GM) with Platelia Aspergillus assay (Bio-Rad) twice weekly from admittance until day 100, and then once weekly until day 365. Following fever occurence or GM optical density index increase (+ve cut-off value was >0.7), screening with weekly chest HR CT scan was started. Diagnosis of IA was made according to the EORTC/MSG criteria. 74 patients were analyzed, and 100 entered by now in the present study. Clinical characteristics of the patients are reported in table 1. We observed 10 cases of probable IA and 2 cases of possible IA. IA occurred before day 40 in 3 patients (median, day 13 after HSCT), between day 40 and day 180 in 8 cases (median, day 109 after HSCT), and after day 180 in 1 patient. Among the probable IA group of patients, 7/10 had GVHD, 6/10 were given steroids, and 3/10 had fever. Two consecutive positive GM test results were observed in the sera of 6/10 patients, GM was detected in BAL only in 3/10 cases and 1 patient had GM detected only in a SNC fluid. Chest CT scan was diagnostic in 8/10 cases, and in another patient CNS RMN scan shown lesions consistent with IA. All patients were lymphopenic at the time of IA diagnosis with an absolute count <450 mm^3, and only 1 patient was neutropenic. 3/10 patients had CMV reactivation during the IA episode and 4/10 had CMV reactivation in the 100 days following IA diagnosis. Cumulative incidence of IA after day 60 was 8,1%, overall incidence of IA was 16.2%, and probability of developing IA reached 24% at 1year after HSCT. Cumulative incidence of IA in the RIC group was 12.3%.6/12 patients died of IA, with a median survival of 24 days (range 1–83). IA accounted for 37.5% (6/16) of all deaths and for 55% of non-relapse deaths. 1-year survival in the IA group was 22% and 80% in non-IA group. Bimodal incidence distribution of IA after HSCT was confirmed, 25% of IA cases were diagnosed early (< day 40) after HSCT, 67% were diagnosed between day 40 and day 180, and an additional 8% developed after day 180. We confirm the role of GVHD and lymphopenia as important risk factors during the late post-transplantation periods. The relatively high incidence of IA could be a consequence of the increase of IA in recent years and of diagnostic improvement (GM+HR CT scan). We recommend the use of serial screening for GM after day 100 in patients lymphopenic or with GVHD. We need new diagnostic and therapeutic strategies for HSCT patients as IA accounts still for an unacceptable high portion of non-relapse deaths. Clinical characteristics of patients Patients 71 Disease Multiple myeloma 27 (38%) Myelodisplastic syndrome 8 (11.3%) Acute myeloid leukemia 9 (12.7%) Chronic myeloid leukemia 6 (8.5%) Hodgkin’s disease 5 (7%) Non Hodgkin’s lymphoma 8 (11.3%) Acute lymphoblastic leukemia 4 (5.6%) Chronic lymphatic leukemia 2 (2.8%) Aplastic anemia 1 (1.4%) Renal cell carcinoma 1 (1.4%) Mean age years (range) 48.8% (20–70) HSCT 74* HLA id RIC 52 (70.3%) MUD RIC 5 (6.8%) HLA id conventional 10 (13.5%) Syngeneic conventional 1 (1.3%) MUD conventional 5 (6.8%) MUD conventional UCB 1 (1.3%) Stem cell source PBSC 64 (86.5%) BM 9 (12.2%) UCB 1 (1.3%) Follow up days Median 214 Min 48 Max 595 GVHD Acute 53/74 (71%) Chronic 36/51 (70%) Chronic extensive 14/36 (39%) *Second transplant 3 patients