Ferrous sulfate microparticles obtained by spray chilling: characterization, stability and in vitro digestion simulation.

The use of microencapsulated ferrous-sulfate is among the various options recommended for food fortification, as the protective wall material surrounding the compound can preserve it from undesirable alterations and also protect the food. Microencapsulated iron can be produced using different wall materials and encapsulation methods. Thus, a microparticle was developed through spray chilling, containing ferrous sulfate (FS), as active compound, and a fat mixture as the coating material. The resulting samples analyzed to determine encapsulation efficiency, particle size distribution, and morphology. Furthermore, the oxidative stability and bioaccessibility of FS microparticles were investigated by simulating in vitro digestion. The findings indicated that the encapsulation technique effectively retained FS, resulting in microparticles physically stable at room temperature with typical morphology. The encapsulation efficiency revealed that lower concentrations of FS led to reduced superficial iron content. However, the oxidative stability demonstrated that the presence of iron in the microparticles accelerated the lipid oxidation process. The in vitro digestion test demonstrated that the microparticles with lower iron content exhibited a higher percentage of bioaccessibility, even when compared to non-encapsulated FS. Additionally, the coating material successfully released FS during the simulation of gastrointestinal digestion, resulting in a bioaccessibility of 7.98%. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05820-1.

Static in vitro digestion methods for assessing essential minerals in processed meat products.

The consumption of processed meat products has increased due to its convenient preparation and characteristics related to taste and consumer acceptance. In this study, we evaluated the content and bioaccessibility of iron (Fe), zinc (Zn), calcium (Ca) and magnesium (Mg) in processed pork and beef products by dialysis assay. In addition, different assays of static in vitro digestion (traditional solubility and INFOGEST) were applied to verify the results on the bioaccessibility of these essential elements. The average content of essential elements (expressed in mg/100 g) were 0.78 ± 0.24 and 1.51 ± 0.51 for Fe; 1.79 ± 0.55 and 3.57 ± 1.42 for Zn; 13.24 ± 9.99 and 20.29 ± 10.45 for Ca and 19.43 ± 2.78 and 26.15 ± 7.33 for Mg, in pork and beef products, respectively. However, we observed high variation between brands and batches. The dialysis assay presented variations in bioaccessibility for all essential elements evaluated in the samples. The results for dialyzable Fe were lower than expected (in vivo assays), probably due to the mechanism simulated in dialysis. This assay was considered inadequate for the simulation of in vitro digestion for meat samples that contain heme-Fe. When comparing the different static in vitro digestion assays employed, the dialysis test showed the lowest bioaccessibility percentages for all essential elements evaluated, when compared with the other in vitro digestion methods. The highest bioaccessible fractions were obtained by applying the INFOGEST protocol. We found that according to the in vitro digestion simulation assay used, the results for bioaccessible percentage displayed high variation. These observations highlight the importance of the assay type used for this purpose. These results did not indicate which is the better assay, but demonstrated the differences of each and their relevance for estimating bioaccessibility of essential elements in meat products.

Accuracy of the median channel shift in the flow cytometry for predicting complement dependent cytotoxicity crossmatching in kidney transplant candidates.

Crossmatching either by complement-dependent cytotoxicity (CDC) and/or by flow cytometry (FCXM) are routinely used for assessing anti-HLA donor antibodies before kidney transplantation. FCXM has demonstrated greater sensitivity and many transplant centers have opted for its use without the concomitant CDC assay. The objective of this study was to evaluate the accuracy of the median channel shift (MCS) in the FCXM in predicting the CDC assay results. A total of 1516 T cell FCXM and 1408 B cell FCXM were studied in deceased donors lymphocytes between January/2016 and March/2017. The high detection rate of CDC+ results by FCXM+ resulted in 87% (FCXM-T) and 90% (FCXM-B) sensitivity, and 98% negative predictive value, for both. The low specificity of FCXM B (43%) is atributed to cases of CDC-/FCXMB+. FCXM T and B were able to detect 53% and 76% of cases with donor specific antibodies of classes I and II with intensity of fluorescence ≥5001. The MCS differentiated CDC+ (Md, P25 and P75) results: MCS-T 390 (245-469) and MCS-B 282 (180-350). Through ROC curve analysis (AUC), the MCS showed satisfactory performance in detecting CDC+: MCS-T 0.909 (0.886-0.933) and MCS-B 0.775 (0.724-0.826). Considering the accuracy and sensitivity evaluation, the MCS-T 245 and MCS-B 282 cutoffs showed a better prediction of CDC+. This study showed that it is possible to calibrate MCS based on CDC+ with accuracy >90%, however, that leads to a risk in terms of non-detection of low-titer anti-HLA antibodies.

Comparative analysis of two methods to detect donor-specific anti-HLA antibodies after kidney transplant.

Preformed anti-human leukocyte antigen (HLA) antibodies may be present in the blood of kidney transplant candidates. The production of these antibodies may occur in the post-transplant period, with the possible development of donor-specific antibodies (DSA). Luminex-based tests, such as the single antigen (SA) assay and the Luminex crossmatch (Xm-DSA) assay are the most commonly used tools to detect anti-HLA antibodies, due to their high sensitivity and specificity. This cross-sectional study aimed to compare the findings of two methods for the detection of DSAs after kidney transplant: SA and Xm-DSA. A total of 122 patients who underwent deceased donor kidney transplant at Hospital de Clínicas de Porto Alegre were included. The SA assay detected anti-class I HLA DSAs in 17 patients (13.9%) and anti-class II HLA DSAs in 22 patients (19.6%), whereas the Xm-DSA detected DSAs in 18 patients (14.8%) both against class I and class II antigens. There was agreement between the two methods for class I (kappa = 0.66, p = 0.001) and class II (kappa = 0.54, p = 0.025) antigens. The incidence of DSAs as obtained by the SA assay was 15.57%, and the most prevalent DSAs were those against HLA-DR antigens. Patient survival at 3 years was 92%. The two techniques assessed in this study provide important information on the presence of DSAs and may help in the post-transplant patient monitoring and in immunosuppressive strategy.

Congenital anomalies: hospitalization in a pediatric unit.

OBJECTIVE: To analyze the profile of children with congenital anomalies admitted to a pediatric unit. METHODS: This is a quantitative and retrospective research. The sample consisted of records of children aged from 0 to 12 years old who were hospitalized in the pediatric unit of the University Hospital of Londrina, Paraná, Southern Brazil, from 2007 to 2009. Data were collected by chart review processed in the Epi-Info® program, and they were submitted to descriptive statistical analysis. RESULTS: There were 282 first admissions of children with congenital anomalies. Of these, 130 (46.0%) required readmission totaling therefore 412 hospitalizations. The mean stay was three days. There was a male predominance, and the age range was from three to seven years old. The most frequent congenital anomalies were in the genital and urinary systems (19.6%), followed by cleft lip and palate (17.3%), and those of the circulatory system (16.2%). There were 269 surgical procedures to correct there anomalies. CONCLUSIONS: This study underscores the epidemiological importance of congenital malformations, highlighting the need to prevent and control the triggering factors.

Caloric profile of pasteurized milk in the human milk bank at a university hospital.

OBJECTIVE: To verify the caloric and sanitary profile of human milk stored at the Human Milk Bank at Londrina University Hospital. METHODS: Cross-sectional study. Data were obtained from the Human Milk Bank registry regarding the source, the amount collected in liters, the amount of calories by liter assessed by crematocrit, and the acidity of human milk determined by titration in degrees Dornic. RESULTS: Between 2006 and 2009, 30,846 samples of human milk were collected from donors coming from different locations and analyzed. A total of 5,869L of milk were collected and distributed. From the total human pasteurized milk, 53,5% was classified as hypocaloric (<580kcal/L); 36.4% as caloric, and 8.3% as hypercaloric (>711kcal/L). Regarding the several locations where the milk was collected, the Human Milk Bank at Londrina University Hospital was the location in which a larger number of donations were observed in the three classifications. The result of the Dornic test for acidity of the collected milk revealed that 60.8% had 4.1º to 8.0º Dornic. CONCLUSIONS: A large volume of the collected human milk is hypocaloric and appropriate for human consumption. There is the need to intensify collection procedures in order to meet the demand for hypercaloric milk for preterm newborn infants.