Discrimination among Fresh, Frozen-Stored and Frozen-Thawed Beef Cuts by Hyperspectral Imaging

The detection of the storage state of frozen meat, especially meat frozen-thawed several times, has always been important for food safety inspections. Hyperspectral imaging (HSI) is widely applied to detect the freshness and quality of meat or meat products. This study investigated the feasibility of the low-cost HSI system, combined with the chemometrics method, to classify beef cuts among fresh (F), frozen-stored (F-S), frozen-thawed three times (F-T-3) and frozen-thawed five times (F-T-5). A compact, low-cost HSI system was designed and calibrated for beef sample measurement. The classification model was developed for meat analysis with a method to distinguish fat and muscle, a CARS algorithm to extract the optimal wavelength subset and three classifiers to identify each beef cut among different freezing processes. The results demonstrated that classification models based on feature variables extracted from differentiated tissue spectra achieved better performances, with ACCs of 92.75% for PLS-DA, 97.83% for SVM and 95.03% for BP-ANN. A visualization map was proposed to provide detailed information about the changes in freshness of beef cuts after freeze-thawing. Furthermore, this study demonstrated the potential of implementing a reasonably priced HSI system in the food industry.

Influence of different post-thaw culture time on the clinical outcomes of different quality embryos

BACKGROUND

In thawed embryo transfer cycles, the most common method is to transfer the embryos after 2 h of culture. Clinical outcomes of frozen-thawed cleavage embryo transfer cycles regarding the embryos status and the culture time of frozen-thawed cleavage embryos were limited and did not elucidate all unclear issues.

OBJECTIVES

The objective of this study was to examine the clinical outcomes of frozen-thawed cleavage embryo transfer cycles according to the embryos status and the culture time (2 h or overnight).

MATERIAL AND METHODS

In this retrospective study (5-year period), 1,654 frozen-thawed embryos were analyzed. Firstly, frozen-thawed cleavage embryos were divided into 2 groups according to their status as follows: with at least 1 optimal embryo and without optimal embryos. Secondly, both of them were divided into 2 groups according to the culture time (2 h or overnight). Age of the female, infertility factors, clinical pregnancy, implantation rate, and live birth rate were compared.

RESULTS

There were no statistically significant differences in the pregnancy rate, the implantation rate, live birth rate, the miscarriage rate, and the ectopic pregnancy rate in each group. However, the implantation rate increased after 2 h of incubation (41.1%) compared to overnight incubation (36.0%) in the group with at least 1 optimal day-3 embryo (p < 0.05). The cancellation rate in the suboptimal day-3 embryos group (9.1%) was higher than in the group containing at least 1 optimal embryo (0.2%) for the long (overnight) culture (p < 0.05).

CONCLUSIONS

The implantation rate can be improved in the optimal day-3 embryos transferred after 2 h of culture, but not for suboptimal day-3 embryos. Some unnecessary transfers can be avoided after overnight culture because of no further cleavage of the embryos.

The Role of Endometrial Volume and Endometrial and Subendometrial Vascularization Parameters in a Frozen Embryo Transfer Cycle

The role of three-dimensional power Doppler ultrasonography of the endometrium in assisted reproduction is still far from clear. In this retrospective cohort study, transvaginal three-dimensional power Doppler examinations were performed 30 min before frozen-thawed embryo transfer. After pregnancy tests, two cohorts were established: P (pregnant, n = 31) and NP (nonpregnant, n = 31). The study only included nullipara with no uterine abnormalities who were undergoing infertility treatment at the Department of Gynecology, Obstetrics and Gynecological Endocrinology, Kepler University Hospital, Linz, Austria. The main outcome measures were the vascularization flow index (VFI), flow index (FI), and vascularization index (VI) in the endometrium/subendometrium, assessed using Virtual Organ Computer-aided AnaLysis (VOCAL™), and the endometrial volume. A total of 62 patients were enrolled in the study, forming two cohorts (pregnant, P; nonpregnant, NP). There were no significant differences between the two cohorts with regard to demographic data, numbers of embryos transferred, or embryo grading, but there was a significant difference in endometrial volume (cohort P, 3.17 ± 0.84 mL; cohort NP, 2.36 ± 0.9 mL; P = 0.001) and the pregnancy rate rises with larger volume. No differences were observed in the vascularization parameters FI, VFI, and VI in the endometrium and subendometrium. In the cohort of pregnant patients, there were 26 (41.9%) live births, with 21 term deliveries (80.8%). The endometrial volume was larger in the cohort of pregnant patients. Measurements were performed 30 min before embryo transfer, and no differences were observed in vascularization parameters in the subendometrium and endometrium.