Objective:To investigate the effect of endometrial thickness(EMT) on the clinical outcome of blastocyst hormone replacement freeze-thawed embryo transfer (HRT-FET) on the first progesterone day, and to analyze the threshold and optimal thickness interval corresponding to ideal clinical pregnancy rate by statistical method.Methods:The endometrial preparation protocols of 2 825 blastocyst HRT-FET cycles from January 2013 to December 2016 in Henan Provincial People′s Hospital and the Second Hospital of Hebei Medical University were studied retrospectively. According to EMT on the first progesterone day, they were divided into 5 subgroups: group Q1(EMT: 3.5-7.9 mm), group Q2(EMT: 8.0-8.9 mm), group Q3(EMT: 9.0-9.5 mm), group Q4(EMT: 9.6-10.7 mm), group Q5(EMT: 10.8-21.0 mm). Univariate analysis, classification multivariate Logistic regression analysis, curve fitting and threshold effect analysis were used to investigate the effect of endometrial thickness on clinical outcome of blastocyst HRT-FET.Results:Group Q1 was set as the control group in classification multivariate Logistic regression analysis, after adjusting for confounding factors, the clinical pregnancy rate and live birth rate in other groups were higher than the control group. The clinical pregnancy rate and live birth rate in group Q3 and Q4 were significantly increased and the differences were statistically significant(all P<0.05). The cut-off value of the endometrial thickness was 9.6 mm. When endometrial thickness was less than 9.6 mm, with 1 mm increase of endometrial thickness, the clinical pregnancy rate increased by 23%( OR=1.23, 95% CI=1.11-1.36) and the live birth rate increased by 21%( OR=1.21, 95% CI=1.10-1.33). When the endometrial thickness was thicker than the threshold, the clinical pregnancy rate did not increase significantly( OR=0.92, 95% CI=0.84-1.02), and the live birth rate showed a downward trend( OR=0.88, 95% CI=0.81-0.96). Conclusions:In the blastocyst HRT-FET cycle, endometrial thickness showes a curvilinear relationship with clinical outcome. The optimal endometrial thickness range for ideal clinical outcome is 9.0-11.0 mm.

Objective:A comparison of method for the detection of hepatitis E virus (HEV) in oysters was performed to provide a technical reference for the detection of HEV in oysters.Methods:After pre-treatment of oyster digestive gland specimens artificially contaminated with HEV fecal suspensions by the proteinase K digestion with reference to the European Union ISO/TS 15216-2∶2019, HEV RNA was extracted by four nucleic acid extraction method and assayed by Real time RT-PCR to compare the HEV recoveries; artificially contaminated oyster digestive gland specimens were pretreated by proteinase K digestion, proteinase K digestion + PEG precipitation, and proteinase K digestion + PEG precipitation + chloroform extraction, respectively, and HEV RNA was extracted by the optimal nucleic acid extraction method, which was assayed by real time RT-PCR to compare the HEV recoveries and inhibition rates of the three pretreatment method. The optimal HEV assay was applied to commercially available oyster specimens.Results:The HEV recoveries of the four nucleic acid extraction methods were 1.37%, 2.50%, 4.24% and 7.56%, respectively, with statistically significant differences ( F=847.220, P<0.001); The HEV recoveries for each of the three pre-treatment method were 6.02%, 13.65% and 21.17%, respectively, with statistically significant differences ( F=16.800, P<0.001), and the proteinase K digestion + PEG precipitation + chloroform extraction method had the highest recovery; the inhibition rates of the three method were 13.38%, 20.98% and 8.66%, respectively, and the differences were statistically significant ( F=20.205, P<0.001), with the lowest inhibition rate for the proteinase K digestion + PEG precipitation + chloroform extraction method. One HEV RNA positive specimen was detected in 120 commercially available oyster specimens. Conclusions:In the HEV detection of oyster specimens, pre-treatment with proteinase K digestion + PEG precipitation + chloroform extraction can improve the recovery of HEV from oysters and is more suitable for pre-treatment of oyster specimens; different manufacturers′ viral nucleic acid extraction method have different HEV recoveries and should be compared and screened for superiority before carrying out the assay.

Objective:To compare the detection method of hepatitis E virus (HEV) in simulated water samples, and to provide a reference for the detection of HEV in water.Methods:HEV fecal suspension was added to tap water or distilled water simulated water samples, and pretreatment was carried out by electropositive filter-organic eluent elution method (Method 1) to compare the extraction effect of the three nucleic acid extraction kits, A, B, and C. The simulated water samples were pre-treated by Method 1, 2 (electropositive filter-direct lysis method), 3 (tangential-flow ultrafiltration membrane-organic eluent elution method), and 4 (tangential-flow ultrafiltration membrane-direct lysis method) for pretreatment, A kit for nucleic acid extraction, Real time RT-PCR method for detection and comparison of the recovery rate; comparison of the recovery rate of different concentrations of HEV in simulated water samples; comparing the inhibitory effects of inhibitors in tap water samples on real time RT-PCR; and detection of HEV in different batches of tap water specimens.Results:Kit A nucleic acid extraction was better; the recoveries of method 1, 2, 3 and 4 were 7.31%, 39.88%, 6.85% and 64.88%, respectively, which showed a statistically significant difference in the recoveries ( F=114.069, P<0.001). The recoveries of method 4 with the addition of high, medium and low concentrations of HEV were 65.26%, 42.76% and 32.79%, respectively. The inhibition of all four pre-treatment method was less than 75%, which meets the requirements of ISO (15216-2∶2019). Twenty tap water specimens were tested for HEV and the result were negative. Conclusions:This study showed that the two membranes better recovered in combination with direct lysis, respectively; Methods 4 had a higher recovery in the detection of HEV in small volumes of distilled or tap water, but it was limited by the volume of water samples, turbidity, and so on. Suitable method can be selected for different water quality and laboratory conditions.

Objective:To optimize and compare method for hepatitis E virus (HEV) nucleic acid detection from pig liver, and provide technical references for HEV detection in animal viscera specimens.Methods:Three methods (PBS homogenization treatment, proteinase K treatment, chloroform extraction method) were used to pretreat and extract viral nucleic acid form pig liver, which was artificially contaminated with HEV fecal suspensions, and HEV RT-qPCR was used to compare the HEV recovery rate and inhibition rate. The optimized HEV method was applied to commercially available pig liver specimens, and HEV genotyping was performed on positive specimens.Results:The HEV recovery rate of PBS homogenization treatment, proteinase K treatment and chloroform extraction method was 9.88%, 0.19% and 17.28%, respectively. The recovery rate of proteinase K treatment was less than 1%, and it was discarded; t-test was performed to compare recovery rates of the other two methods, which showed statistically significant differences ( t=26.801, P<0.001), the chloroform extraction method had a higher recovery rate. The inhibition rates of the three methods were all less than 75%, within the range of the ISO/TS 15216-2∶2019 standard. Among 192 commercially available pig liver specimens, 17 specimens were detected positive for HEV RNA, with a nucleic acid positive rate of 8.85%; five specimens were successfully genotyped for HEV, all of which were genotype 4. Conclusions:The virus recovery effect was good when chloroform extraction method was used for pig liver pretreatment; moreover, this method could detect HEV RNA from commercially available pig livers, which indicate that it can be used for virus detection in food.

Zn²⁺ is required for the activity of many mitochondrial proteins, which regulate mitochondrial dynamics, apoptosis and mitophagy. However, it is not understood how the proper mitochondrial Zn²⁺ level is achieved to maintain mitochondrial homeostasis. Using Caenorhabditis elegans, we reveal here that a pair of mitochondrion-localized transporters controls the mitochondrial level of Zn²⁺. We demonstrate that SLC-30A9/ZnT9 is a mitochondrial Zn²⁺ exporter. Loss of SLC-30A9 leads to mitochondrial Zn²⁺ accumulation, which damages mitochondria, impairs animal development and shortens the life span. We further identify SLC-25A25/SCaMC-2 as an important regulator of mitochondrial Zn²⁺ import. Loss of SLC-25A25 suppresses the abnormal mitochondrial Zn²⁺ accumulation and defective mitochondrial structure and functions caused by loss of SLC-30A9. Moreover, we reveal that the endoplasmic reticulum contains the Zn²⁺ pool from which mitochondrial Zn²⁺ is imported. These findings establish the molecular basis for controlling the correct mitochondrial Zn²⁺ levels for normal mitochondrial structure and functions.
Animals ; Caenorhabditis elegans/metabolism* ; Cation Transport Proteins/genetics* ; Homeostasis ; Mitochondria/metabolism* ; Zinc/metabolism*