Intermittent spontaneous ovulation in patients with premature ovarian failure: Three case reports and review of literature

BACKGROUND

Premature ovarian failure (POF) is the end-stage of a decline in ovarian function prior to the age of 40 years that involves symptoms associated with low estradiol (E₂) levels and a minimal probability of pregnancy. This increases the physical and psychological burden experienced by young women of reproductive age, particularly with regards to over-diagnosis.

CASE SUMMARY

Here, we report three cases (29, 22, and 33 years-of-age) diagnosed with POF after experiencing secondary amenorrhea for more than one year, serum levels of follicle-stimulating hormone (FSH) > 40 IU/L on two occasions with an interval of more than 4 wk, and negative progesterone withdrawal tests. All three patients were intermittently administered with drugs to create an artificial cycle. During the subsequent discontinuation period, the patients experienced intermittent follicular growth and spontaneous ovulation. One patient experienced two natural pregnancies (both with embryo arrest).

CONCLUSION

Our findings suggest that young patients with POF can experience unpredictable and intermittent spontaneous follicular development, ovulation, and even natural pregnancy. Clinicians should provide appropriate medical guidance and individualized treatments according to fertility requirements, genetic risks and hypoestrogenic symptoms as soon as possible.

The effect of pre-ESRD care program on potentially inappropriate medication in advanced CKD patients

Background

Due to the multiple comorbidities and the associated complications among advanced CKD population, assessing potentially inappropriate medications (PIM) in these patients is an important task for physicians and multidisciplinary care team members. This study aimed to investigate the impact of the national pre-ESRD pay-for-performance (P4P) program on prescribing quality in Taiwan.

Methods

We conducted a retrospective cohort study using data from National Health Insurance Research Database (NHIRD) maintained by the Health and Welfare Data Science Center, Ministry of Health and Welfare (HWDC, MOHW). The incidents of CKD in year 2010 were observed until the end of 2017. Adult patients who initiated maintenance dialysis therapy were enrolled. To identify the use of PIM that should be avoided in advanced CKD patients, the Beers 2019 criteria and latest Taiwan Manual of Renal Injury Prevention and Drug Safety were applied. We measured PIM use in one year before starting long-term dialysis.

Results

Among 7,828 participants underwent continuous dialysis treatment, 2,119 (27.1%) were P4P patients. Most (90.4%) participants were prescribed one or more PIMs before ESRD initiation. After adjusted age, sex, Charlson Comorbidity Index (CCI) and the number of nephrologist visits, the logistic regression showed lower probability of PIM use in the P4P enrollees (OR = 0.56, 95% CI = 0.47-0.66). The effect of P4P on PIM was more prominent in the subgroups of patients who were female and CCI≤3.

Conclusions

The implementation of the pre-ESRD P4P program might reduce PIM use among CKD patients. Our results underline the strategy of financial incentives in the payment design to improve prescribing patterns.

Key messages

Prescribing potentially inappropriate medications is common among patients who were approaching ESRD. The study highlights the importance of implementing the pre-ESRD P4P program to reduce PIM use in advanced CKD patients.

[Involvement of Src kinase in the down-regulation of ultra-rapid delayed rectifier K(+)current induced by tumor necrosis factor-α in cardiomyocytes]

Objective: To investigate whether inflammatory factor tumor necrosis factor-α (TNF-α) is involved in the electrical remodeling of cardiomyocytes by regulating ultra-rapid delayed rectifier K(+) current (I(kur)) and the role of Src kinase. Methods: H9c2 cells, embryonic cardiomyocytes of rat, were cultured in Dulbecco's modified Eagle's medium (DMEM) and atrium-derived HL-1 cells were cultured in Claycomb medium. Both H9c2 and HL-1 cells were cultured at 37 ℃ with 5% CO(2). Cells cultured in normal conditions without additional treatment served as control group. Experimental groups were treated with different concentration of TNF-α (25 or 50 or 100 ng/ml) for 24 hours. To study whether Src specific inhibitor PP1 could abrogate the effect of TNF-α, cells were pre-treated with 10 μmol/L PP1 for 1 hour, followed by TNF-α (100 ng/ml) for 24 hours. Western blot and the whole cell patch clamp technique were used to detect the protein expression of Kv1.5 and Src and I(kur) in each group. Results: (1) In H9c2 cells, high concentration of TNF-α treatment (100 ng/ml) significantly reduced the Kv1.5 protein expression compared with control group and TNF-α 25 ng/ml group (both P<0.05). Compared with control group, the expression of p-Src protein was higher in 25 ng/ml, 50 ng/ml, 100 ng/ml TNF-α group (all P<0.05), but there was no statistical difference in the expression of Src protein among groups (P>0.05). In addition, the current density of I(kur) was decreased in 50 ng/ml, 100 ng/ml TNF-α group (both P<0.05). Furthermore, the expression of Kv1.5 protein and the current density of I(kur) were increased in PP1+TNF-α group compared with TNF-α 100 ng/ml group (both P<0.05). There was no statistical difference in the expression of Kv1.5 protein and the current density of I(kur) between the control group and PP1+TNF-α group (both P>0.05). (2) In atrium-derived HL-1 cells, the expression of Kv1.5 protein was reduced in 100 ng/ml TNF-α group compared with control group and TNF-α 25 ng/ml group (both P<0.01). In addition, the expression of p-Src protein was increased in TNF-α 100 ng/ml group compared with control group (P<0.05), but there was no statistical difference in the protein expression of Src among groups (P>0.05). The expression of Kv1.5 protein was increased in PP1+TNF-α group compared with TNF-α 100 ng/ml group (P<0.05). Conclusion: TNF-α is involved in the pathogenesis of atrial fibrillation, probably via decreasing I(kur) current density in atrium-derived myocytes through the activation of Src kinase.

Factors Associated with Effectiveness of Treatment and Reproductive Outcomes in Patients with Thin Endometrium Undergoing Estrogen Treatment

Background:

Thin endometrium is associated with poor reproductive outcomes; estrogen treatment can increase endometrial thickness (EMT). The aim of this retrospective cohort study was to investigate the factors influencing the effectiveness of estrogen treatment and reproductive outcomes after the treatment in patients with thin endometrium.

Methods:

Relevant clinical data of 101 patients with thin endometrium who had undergone estrogen treatment were collected. Possible factors influencing the effectiveness of treatment were analyzed retrospectively by logistic regression analysis. Eighty-seven infertile women without thin endometrium who had undergone assisted reproduction served as controls. The cases and controls were matched for age, assisted reproduction method, and number of embryos transferred. Reproductive outcomes of study and control groups were compared using Student's t-test and the Chi-square test.

Results:

At the end of estrogen treatment, EMT was ≥8 mm in 93/101 patients (92.1%). Effectiveness of treatment was significantly associated with maximal pretreatment EMT (P = 0.017) and treatment duration (P = 0.004). The outcomes of assisted reproduction were similar in patients whose treatment was successful in increasing EMT to ≥8 mm and the control group. The rate of clinical pregnancy in patients was associated with the number of good-quality embryos transferred in both fresh (P = 0.005) and frozen-thawed (P = 0.000) embryo transfer cycles.

Conclusions:

Thinner EMT before estrogen treatment requires longer treatment duration and predicts poorer treatment outcomes. The effectiveness of treatment depends on the duration of estrogen administration. Assisted reproductive outcomes of patients whose treatment is successful (i.e., achieves an EMT ≥8 mm) are similar to those of controls. The quality of embryos transferred is an important predictor of assisted reproductive outcomes in patients treated successfully with exogenous estrogen.

Pregnancy Outcomes of In Vitro Fertilization with or without Ovarian Hyperstimulation Syndrome: A Retrospective Cohort Study in Chinese Patients

Background:

The effect of ovarian hyperstimulation syndrome (OHSS) on pregnancy outcomes of in vitro fertilization (IVF) patients is still ambiguous. This study aimed to analyze pregnancy outcomes of IVF with or without OHSS in Chinese patients.

Methods:

A retrospective cohort study was undertaken to compare pregnancy outcomes between 190 women with OHSS and 197 women without OHSS. We examined the rates of clinical pregnancy, multiple pregnancies, miscarriage, live birth, preterm delivery, preterm birth before 34 weeks’ gestation, cesarean delivery, low birth weight (LBW), and small-for-gestational age (SGA) between the two groups. Odds ratios (ORs) and 95% confidence intervals (CIs) of measure of clinical pregnancy were also analyzed.

Results:

The clinical pregnancy rate of OHSS patients was significantly higher than that of non-OHSS patients (91.8% vs. 43.5%, P < 0.001). After controlling for drug protocol and causes of infertility, the adjusted ORs of moderate OHSS and severe/critical OHSS for clinical pregnancy were 4.65 (95% CI, 1.86–11.61) and 5.83 (95% CI, 3.45–9.86), respectively. There were no significant differences in rates of multiple pregnancy (4.0% vs. 3.7%) and miscarriage (16.1% vs. 17.5%) between the two groups. With regard to ongoing clinical pregnancy, we also found no significant differences in the rates of live birth (82.1% vs. 78.8%), preterm delivery (20.9% vs. 17.5%), preterm birth before 34 weeks’ gestation (8.6% vs. 7.9%), cesarean delivery (84.9% vs. 66.3%), LBW (30.2% vs. 23.5%), and SGA (21.9% vs. 17.6%) between the two groups.

Conclusion:

OHSS, which occurs in the luteal phase or early pregnancy in IVF patients and represents abnormal transient hemodynamics, does not exert any obviously adverse effect on the subsequent pregnancy.

Field homogeneity improvement of maglev NdFeB magnetic rails from joints

An ideal magnetic rail should provide a homogeneous magnetic field along the longitudinal direction to guarantee the reliable friction-free operation of high temperature superconducting (HTS) maglev vehicles. But in reality, magnetic field inhomogeneity may occur due to lots of reasons; the joint gap is the most direct one. Joint gaps inevitably exist between adjacent segments and influence the longitudinal magnetic field homogeneity above the rail since any magnetic rails are consisting of many permanent magnet segments. To improve the running performance of maglev systems, two new rail joints are proposed based on the normal rail joint, which are named as mitered rail joint and overlapped rail joint. It is found that the overlapped rail joint has a better effect to provide a competitive homogeneous magnetic field. And the further structure optimization has been done to ensure maglev vehicle operation as stable as possible when passing through those joint gaps. The results show that the overlapped rail joint with optimal parameters can significantly reduce the magnetic field inhomogeneity comparing with the other two rail joints. In addition, an appropriate gap was suggested when balancing the thermal expansion of magnets and homogenous magnetic field, which is considered valuable references for the future design of the magnetic rails.

Short Communication: Molecular cloning and expression pattern of the porcine 5-aminolevulinate synthase 1 (ALAS1) gene and its association with reproductive traits

5-Aminolevulinate synthase 1 (ALAS1) is the first enzyme in the heme biosynthetic pathway and is upregulated in follicular tissue during the early stages of ovulation. In this study, we isolated the complete coding sequence of the porcine ALAS1 gene and its 2-9 intron sequence, identified a single nucleotide polymorphism (SNP; T/C) in intron 9, and developed a PCR-MspI-restriction fragment length polymorphism genotyping assay. Association of the SNP with litter size was assessed in two populations [purebred Large White and the experimental synthetic (DIV) line]. Statistical analysis demonstrated that for total number of piglets born (TNB) in all parities, pigs with the CC genotype had an additional 0.68 and 0.74 piglets compared to the TC and TT animals (P < 0.05) in the DIV line, respectively. Purebred Large White sows inheriting the CC and TC genotypes gave birth to an additional 0.96 and 0.70 piglets compared to the TT animals (P < 0.05) in all parities, respectively. In addition, for TNB in all parities, a significant additive effect of 0.48 ± 0.23 and 0.37 ± 0.17 piglets/ litter was detected in sows of both populations (P < 0.05), respectively. The highest levels of ALAS1 gene expression were observed in isolated ovarian granulosa cells 2 and 12 h after stimulation with pregnant mare serum gonadotropin human chorionic gonadotropin, which represents the time of follicular development and ovulation, respectively. Therefore, the ALAS1 gene was significantly associated with litter size in two populations and could be a useful molecular marker for the selection of increasing litter size in pigs.

Fertility-sparing treatment of low-grade endometrial stromal sarcoma

Low-grade endometrial stromal sarcoma (ESS) is a kind of uterine malignancy. Total hysterectomy and bilateral salpingo-oophorectomy was the main treatment. We evaluate the feasibility of fertility-sparing management in five patients with low-grade ESS who desired for childbearing. The patients aged 28-36 years old presented with symptoms of menometrorrhagia or without symptom. Ultrasound examinations demonstrated leiomyomas (with the diameter of 3.5-6 cm respectively). All the patients received conservative surgeries of local resection of the mass with uterine reconstruction. Then the adjuvant endocrine therapy was given to them with megestrol acetate (160-320 mg/day) or triptorelin (3.75 mg/28 days) for 5-6 months. The follow-up lasted 21-55 months. All the patients survived. Three of them underwent an uncomplicated pregnancy, and received cesarean delivery of a liveborn neonate. One of them is alive without disease recurrence. The other one found disease recurred during the megestrol acetate treatment, and received hysterectomy. We consider that fertility-sparing treatment is suitable in selected in young low-grade ESS patients especially for those whose lesion was with a clear borderline. Adjuvant endocrine therapy is recommended for about 6 months after operation.

Large-Scale and Selective Synthesis of Carbon Nanofiber Bundles, Curved Carbon Nanofibers and Helical Carbon Nanofibers

Through the pyrolysis of acetylene at 250 °C, large quantities of carbon nanofiber bundles (CNFBs), curved carbon nanofibers (CCNFs) and helical carbon nanofibers (HCNFs) can be synthesized selectively by controlling the Fe:Cu molar ratio of Fe-Cu nanoparticles. In this study, the systematic experimental results indicated that the Cu content in the Fe-Cu nanoparticles and pyrolysis temperature had great impact on the yield and structure of the final samples. Moreover, the transmission electron microscopic observation indicated that the catalyst nanoparticles were enwrapped tightly by graphite layers, and the obtained HCNFs show good magnetic property. Compared to the methods reported in the literature, the approach described herein has the advantages of being simple, low-cost, and environment-friendly. It is suitable for the controllable and mass production of CNFBs, CCNFs and HCNFs.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H₂O₂), but not angiotensin II, stimulated MIF expression in HL-1 cells. H₂O₂-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H₂O₂-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

Assessment of genomic imprinting of PPP1R9A, NAP1L5 and PEG3 in pigs

Imprinted genes play significant roles in the regulation of fetal growth and development, function of the placenta, and maternal nurturing behaviour in mammals. At present, few imprinted genes have been reported in pigs compared to human and mouse. In order to increase understanding of imprinted genes in swine, a polymorphism-based approach was used to assess the imprinting status of three porcine genes in 12 tissue types, obtained from F1 pigs of reciprocal crosses between Rongchang and Landrace pure breeds. In contrast to human and mouse homologues, porcine PPP1R9A was not imprinted, and was found to be expressed in all tissues examined. The expression of porcine NAP1L5 was detected in pituitary, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, ovary, and uterus, but undetectable in heart. Furthermore, porcine NAP1L5 was paternally expressed in the tissues where it's expression was observed. For PEG3, pigs expressed the paternal allele in skeletal muscle, liver, spleen, kidney, and uterus, but biallele in heart, lung, fat, stomach, small intestine, and ovary. Our data indicate that tissue distribution of the three gene differs among mammals, and the imprinting of NAP1L5 and PEG3 is well conserved.

Immune modulation of co-transplantation mesenchymal stem cells with islet on T and dendritic cells

Allogeneic pancreatic islet transplantation theoretically represents a cure for type 1 diabetes. However, current immune suppressive therapies are often associated with undesired side effects. Given this problem, and the shortage of human islet donors, the majority of type 1 diabetes patients cannot currently be offered an islet transplant. However, it has been found that mesenchymal stem cells (MSCs) could exert unique immunosuppressive effects both in vitro and in vivo. Herein we transplanted allogeneic 200 islets alone or in combination with MSCs (3 x 10(6) cells) under the kidney capsules of diabetic C57LB/6 mouse. We found that the ratios of T helper type 1 (Th1) to Th2 and Tc1 to Tc2 were reduced, and the numbers of naive and memory T cells were down-regulated in peripheral blood after transplantation. In addition, the maturation, endocytosis and interleukin-12 secretion of dendritic cell (DCs)-derived bone marrow cells (BMCs) from receptor mice were suppressed. Rejection reaction was alleviated by MSCs which exerted suppressive effects through T lymphocyte subsets and DCs.

Real-time reverse transcription-PCR expression profiling of porcine troponin I family in three different types of muscles during development

In this study, the expression profiling of three troponin I isoforms (TNNI1, TNNI2 and TNNI3) was investigated in two pig breeds differing in muscularity (Yorkshire and Meishan) at six stages (fetal 60 days and postnatal 3, 35, 60, 120, and 180 days) and three types of muscles (longissimus dorsi muscle, LD; semitendinosus, ST; cardiac muscle, CM) using relative real-time quantitative PCR. Significant differences of troponin I expression in three muscles were found between Yorkshire and Meishan breeds at some stages. The expression peak of TNNI1 and TNNI2 in LD and ST was at postnatal 35 or 60 days in Yorkshire and at postnatal 120 or 180 days in Meishan pigs, while it occurred in CM at postnatal 3 days in two pig breeds. The relative expression values of TNNI1 and TNNI2 were significantly higher in LD than ST at most of stages after birth. The expression ratio of TNNI2 versus TNNI1 favoured TNNI2 expression in ST and LD, but on the contrary in CM. The expression peak of TNNI3 occurred at postnatal 60 and 120 days in Yorkshire and Meishan pigs, respectively. TNNI1 and TNNI3 were co-expressed in CM during the fetal and earlier stages after birth.

Comparison of approaches for efficient gene silencing induced by microRNA-based short hairpin RNA and indicator gene expression

MicroRNA-based short hairpin RNAs (shRNAs) are natural inducers of RNA interference and have been increasingly used in shRNA expression strategies. In the present study, we compared the efficiencies of exogenous green fluorescence protein (GFP) and endogenous glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knockdown and red fluorescent protein (RFP) indicator expression mediated by three differently designed plasmids. RFP was introduced either at the 5' end, at the 3' end of the human mir155-based target gene (TG) (e.g., GFP or GAPDH) shRNA expression cassette (EC), or at the 3' end of the chimeric intron-containing TG shRNA EC. Comparisons with the control vector showed an obvious reduction of GFP or GAPDH expression with the various shRNA expression plasmids (P < 0.05). When RFP was located at the 5' end or at the 3' end of the TG shRNA EC, RFP expression was low; whereas when RFP was connected with the chimeric intron-containing TG shRNA EC, RFP expression was high. Taken together, this study demonstrated an efficient plasmid design for both TG silencing induced by microRNA-based shRNA and indicator gene expression in vitro.

MyoD control of SKIP expression during pig skeletal muscle development

Skeletal muscle and kidney enriched inositol phosphatase (SKIP) was identified as a 5'-inositol phosphatase that hydrolyzes PI(3,4,5)P3 to PI(3,4)P2 that negatively regulates insulin-induced phosphatidylinositol 3-kinase signaling in skeletal muscle. In this study, we obtained a 1575-bp mRNA sequence of porcine SKIP that included the full coding region encoding a protein of 450 amino acids. With the use of comparative mapping, we mapped this gene to SSC12 q1.3, where many QTLs affect Backfat thickness at 10th rib, carcass yield, the number of muscle fibers, and ham weight traits. As a candidate gene for growth and carcass traits, a novel single nucleotide polymorphism in exon 12 (G>A) was detected by PCR-RFLP. The results showed that the GG genotype had higher skin percentage (SP), carcass length to first spondyle (CL1), carcass length to first rib (CL2), but lower intramuscular fat (IMF) as compared with genotype AG (P<0.05), and allele G seemed to be associated with an increase in the growth trait. Porcine SKIP was expressed abundantly in skeletal muscle tissue and was transcriptionally upregulated during skeletal muscle differentiation. Analysis of the porcine SKIP promoter sequence demonstrated that MyoD was involved in regulating SKIP mRNA expression in myotubes, partly via the cis-acting elements in SKIP promoter. In summary, we suggested that SKIP might play a role in the regulation of skeletal muscle development in pigs.

Identification of three novel SNPs and association with carcass traits in porcine TNNI1 and TNNI2

In this study, two novel SNPs (EU743939:g.5174T>C in intron 4 and EU743939:g.8350C>A in intron 7) in TNNI1 and one SNP (EU696779:g.1167C>T in intron 3) in TNNI2 were identified by PCR-RFLP (PCR restriction fragment length polymorphism) using XbaI, MspI and SmaI restriction enzyme, respectively. The allele frequencies of three novel SNPs were determined in the genetically diverse pig breeds including ten Chinese indigenous pigs and three Western commercial pig breeds. Association analysis of the SNPs with the carcass traits were conducted in a Large White × Meishan F(2) pig population. The linkage of two SNPs (g.5174T>C and g.8350C>A) in TNNI1 gene had significant effect on fat percentage. Besides these, the g.5174T>C polymorphism was also significantly associated with skin percentage (P < 0.05), shoulder fat thickness (P < 0.05) and backfat thickness between sixth and seventh ribs (P < 0.05). The significant effects of g.1167C>T polymorphism in TNNI2 gene on fat percentage (P < 0.01), lean meat percentage (P < 0.05), lion eye area (P < 0.05), thorax-waist backfat thickness (P < 0.01) and average backfat thickness (P < 0.05) were also found.

[Clinical applications of anti-Müllerian hormone in evaluating ovarian reserve functions]

Anti-Müllerian hormone (AMH) is a member of the transforming growth factor (TGF)-beta superfamily and mainly expressed by the granulosa cells of ovarian follicles. In women AMH is only expressed in ovarian follicles and therefore can be used for the evaluation of the ovarian reserve function and the prediction of ovary ageing and ovarian response during in vitro fertilization (IVF) treatment. This article summarizes the clinical application of AMH, especially in evaluating ovarian reserve functions.

Polymorphism of the pig 17beta-hydroxysteroid dehydrogenase type1 (HSD17B1) gene and its association with reproductive traits

17beta-Hydroxysteroid dehydrogenase type 1 (HSD17B1) is a key enzyme of 17beta-estradiol biosynthesis, which might play an important role in follicular development of the ovary. In this study, we isolated the complete coding sequence of porcine HSD17B1 gene and its unique intron sequences of porcine HSD17B1 gene, identified a single nucleotide polymorphism (SNP: A/C) in intron 4, and developed a PCR-MvaI-RFLP genotyping assay. Association of the SNP and litter size was assessed in two populations (purebred Large White and a experimental synthetic Line (DIV) sows). Statistical analysis demonstrated that, in the first parity, AC animals in experimental synthetic Line (DIV) sows had 0.52 more piglets born compared to the CC animals (P<0.05). In the all parities, pigs with the AA genotype had an additional 1.11 and 0.96 piglets born alive compared to the CC animals (P<0.05) in both experimental synthetic Line (DIV) and purebred Large White, respectively. Experimental synthetic Line (DIV) sows inheriting the AC genotype had additional 0.84 piglets born alive compared to the CC animals (P<0.01) in all parities. In addition, significant additive effect of -0.55+/-0.24 piglets/litter and -0.48+/-0.22 piglets/litter on piglet born alive was detected in both experimental synthetic Line (DIV) sows and purebred Large White lines (P<0.05), respectively. Therefore, HSD17B1 gene was significantly associated with litter size in two populations and could be a useful molecular marker in selection for increasing litter size in pigs.

[Application of vitrification of human oocytes and embryos at different developmental stages]

Vitrification of human oocytes and embryos has become an important assisted reproductive technology. It can be used to cryopreserve immature oocytes, mature oocytes, pronuclear embryos, blastomeres, and blastocysts. This article reviewed the clinical application of vitrification of human oocytes and embryos at different developmental stages.

Molecular characterization and SNPs analysis of the porcine Deleted in AZoospermia Like (pDAZL) gene

The Deleted in AZoospermia Like (DAZL) gene is expressed in prenatal and postnatal germ cells. In this study, we cloned and characterized the porcine Deleted in AZoospermia Like (pDAZL) gene. We found the full-length coding sequence of the pDAZL encoded a protein of 295 amino acids with a RNA recognition motif (amino acids 41-111) and a DAZ repeat (amino acids 167-120). The deduced protein sequence of pDAZL is 92.5% and 91.5% similar to those of human and bovine, respectively. PCR-MspI-RFLP and PCR-TaqI-RFLP were established to detect an A/G mutation in intron 7 and a C/A mutation in intron 9, respectively. Associations of two SNPs with litter size traits were assessed in Large White (n=275) and DIV (n=128) pig populations, and the statistical analysis demonstrated that CC produced 0.716 more (P<0.05) piglets born alive than CD genotypes in Large White pigs at TaqI locus (C/A mutation in intron 9), and the dominance effect was 0.304 pig per litter (P<0.05). This result suggests that the pDAZL gene might be a good candidate gene of litter size trait and provides some marker information for marker-assisted selection (MAS).

Isolation and imprinting analysis of the porcine DLX5 gene and its association with carcass traits

Imprinted genes play important roles in mammalian growth and development. However, reports on imprinted genes are limited in livestock. In this study, the complete ORF containing 289 amino acids of the porcine DLX5 gene was obtained. A C-to-T SNP mutation in exon 1 of the DLX5 gene was used to detect imprinting status with an RT-PCR/RFLP test (using HhaI) in eight heterozygous pigs from a population of Large White x Meishan F(1) hybrids. Imprinting analysis showed that the porcine DLX5 gene was maternally expressed in skeletal muscle, fat, lung, spleen, stomach and small intestine, but not imprinted in heart, liver, kidney, uterus, ovary, testicle or pituitary. A PCR-RFLP test was also used to detect the polymorphism in 310 pigs of a Large White x Meishan F(2) resource population. The statistical results showed significant association (P < 0.01) of the genotypes and fat meat percentage, carcass length, bone percentage, 6-7 rib fat thickness, average backfat thickness, thorax-waist fat thickness and buttock fat thickness.

Esmolol inhibits Na+ current in rat ventricular myocytes

Esmolol is a unique cardioselective, intravenous, ultra-short acting, beta1-adrenergic blocking agent. It has been widely applied in treating ventricular and supraventricular arrhythmias, especially in emergency situations. In this study the effects of esmolol on sodium current (I(Na)) were investigated by the whole cell patch-clamp recording technique in isolated adult rat ventricular myocytes. The results indicated that esmolol reversibly inhibited I(Na) in a concentration-dependent manner, with an IC50 of 74.2 +/- 0.60 micromol l(-1) with a Hill coefficient of 1.02 +/- 0.04. This inhibition was voltage- and frequency-dependent. Esmolol decreased the peak of the I-V relationship curve at -35 mV from 16.97 +/- 1.68 pA/pF to 6.96 +/- 0.51 pA/pF. The steady-state inactivation curve of I(Na) was shifted to more negative potentials, the voltage at half-inactivation changing from -78.75 +/- 2.3 mV in control to -85.94 +/- 3.2 mV in the presence of esmolol. The development of resting inactivation from closed states was accelerated by esmolol, the time constant was shortened from 62.75 +/- 3.21 ms to 24.93 +/- 2.43 ms, whereas the activation curve was not altered. I(Na) from inactivation could not be recovered completely in the presence of esmolol. These results suggest that esmolol inhibits I(Na) through sodium channel in rat ventricular myocytes by mechanisms involving preferential interaction with the inactivated state and acceleration of the development of inactivation directly from resting state. Therefore, the effect of inhibitory sodium of esmolol may play a vital role in its antiarrhythmic efficacy.

Imprinted status of pleomorphic adenoma gene-like I and paternal expression gene 10 genes in pigs1

Genomic imprinting is theorized to exist in all placental mammals and some marsupials. Imprinted genes play important roles in the regulation of fetal growth, development, and postnatal behavior, but the study of imprinted genes has been limited in livestock. In this study, the polymorphism-based approach was used to detect the expression patterns of the porcine pleomorphic adenoma gene-like I (PLAGL1) and paternal expression gene 10 (PEG10) genes. Single nucleotide polymorphisms in the exons were detected between the Meishan and Large White breeds in the PLAGL1 and PEG10 genes. The polymorphisms were used to determine the monoallelic or biallelic expression with reverse transcription-PCR-RFLP in 44 tissues from 4 heterozygous pigs (based on SNP). Imprinting analysis indicated that the PLAGL1 and PEG10 genes were both paternally expressed in all tissues tested (heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus, and ovary). Our study showed that the method of identifying polymorphic transcripts with reverse transcription-PCR-RFLP may be beneficial for detecting the imprinting status of some candidate imprinted genes.

Identification of a differential gene HUMMLC2B between F1 hybrids Landrace x Yorkshire and their female parents Yorkshire

In order to investigate heterosis on a molecular basis, suppression subtractive hybridization was used to analyze the differences in gene expression between porcine F1 hybrids Landrace x Yorkshire and their female parents Yorkshire. From two specific subtractive cDNA libraries, the clones screened out by reverse Northern high-density blots screening were chosen to clone full-length cDNA by RACE. An expression-upregulated gene for Yorkshire skeletal muscle, designated as HUMMLC2B, was identified. Porcine HUMMLC2B contains an open reading frame (ORF) encoding 169 amino acids residues with 59 and 115 nucleotides in the 5' and 3' untranslated regions (UTRs), respectively. In the porcine genome, it contains seven exons separated by six introns. High allelic variations and four SINEs were detected in it. Comparison of derived amino acid sequence of HUMMLC2B with database sequences revealed highly conserved 12 amino acid residues in a putative calcium-binding region. RT-PCR analysis showed a tissue-specific pattern of expression in skeletal muscle and a similar level of expression during skeletal muscle development. The possible role of HUMMLC2B and its relation to porcine heterosis are discussed.

Polymorphism, linkage mapping and expression pattern of the porcine skeletal muscle glycogen synthase (GYS1) gene

The glycogen synthase gene (GYS1), which encodes the rate-limiting enzyme for glycogen synthesis of skeletal muscle, is a promising candidate gene for traits related to skeletal muscle in pigs. In this study, a G/A single nucleotide polymorphism in GYS1 intron 7 detected as a FokI PCR-restriction fragment length polymorphism (PCR-RFLP) showed allele frequency differences among five Chinese indigenous pig breeds and three western commercial pig breeds. Linkage analysis assigned the gene GYS1 to marker interval SW1302-SW1473 on SSC6 in a three-generation Meishan X Large White reference family. The results of association analysis and interval mapping suggested that the FokI PCR-RFLP polymorphism might be linked with the quantitative trait loci affecting carcass traits detected on SSC6 in the F2 intercross pedigree. The reverse transcriptase-polymerase chain reaction revealed that the porcine GYS1 gene was expressed in spleen, lung, liver, kidney, small intestine, skeletal muscle, heart and stomach, with the highest expression in skeletal muscle.

cDNA cloning, genomic structure and polymorphism of the porcine FHL3 gene

LIM domain proteins are important regulators of the growth, determination and differentiation of cells. Four-and-a-half LIM-only protein 3 (FHL3) is a type of LIM-only protein that contains four tandemly repeated LIM motifs with an N-terminal single zinc finger (half LIM motif). In this study, we have determined the complete coding sequence of pig FHL3 which encodes a 280 amino acid protein. The coding region of the pig FHL3 gene is organized in five exons and spans an approximately 2.1-kb genomic region. Comparative sequencing of six pig breeds revealed three single nucleotide polymorphisms (SNPs) within exon 2 of which an A-->G substitution at position 313 changes a codon for arginine into a codon for glycine. The substitution was situated within a PstI recognition site and developed as a PCR-RFLP marker for further use in population variation investigations and association analysis. The A/G polymorphism was segregating only in Landrace pigs. Association studies of the FHL3 polymorphism with carcass traits provided preliminary evidence that the PstI PCR-restriction fragment length polymorphism (RFLP) genotype may be associated with variation in several carcass traits of interest for pig breeding. Further investigations in more Landrace pigs are needed to confirm this.

[Superovulation and intrauterine insemination in treatment of idiopathic infertility in 202 cycles]

OBJECTIVE

To evaluate the effect of superovulation with recombinant follicle stimulating hormone (r-FSH) therapy and intrauterine insemination in the treatment of idiopathic infertility.

METHODS

Superovulation with r-FSH therapy and intrauterine insemination were used in 202 cycles of 88 couples in the Department of Obstetrics and Gynecology of Monash Medical Centre.

RESULTS

The per cycle ovulation rate and in-ovulation rate were 95.7% and 4.3% respectively, and the per cycle pregnancy rate was 11.6% with no cases of hyperstimulation. The cancelling rate was 7.4% because of the development of multiple follicles. The overall cumulative conception rate was 22.7% per patient, with 15% of twin pregnancies. There were no differences between pregnancy group and non-pregnancy group in age, BMI, treatment days, number of mature follicles, endometrial thickness and number of treatment cycles. The only significant parameter observed between the two groups was infertility time (P < 0.05), which was longer in non-pregnancy group [(30.52 +/- 13.08) months] than in pregnancy group [(24.25 +/- 6.45) months].

CONCLUSIONS

Superovulation and intrauterine insemination is a safe and more cost-effective method in treatment of idiopathic infertility.

[Polymorphism of porcine hormone sensitive lipase gene and sequencing the partial DNA fragments]

Hormone sensitive lipase (HSL) is a key enzyme in fat metabolism. The polymorphism of the pig HSL gene is studied in this paper. The SSCP (Single Strand Conformational Polymorphism) is found in the HSL gene Exon 8. It shows three genotypes (MM, MN, NN). Fat-type pig breeds of Meishan and Tongcheng pigs have more allele M, with frequencies of 0.690 M and 0.740 M, respectively; however, lean-type pig breeds of Landrace and the Large White pigs have more allele N, with frequencies of 0.847 N and 0.845 N, respectively. PCR fragments representing HSL genotypes MM and NN are sequenced. Two A-->G transitions are detected, and it resulted in corresponding changes of amino acid (Asn-->Asp and Glu-->Gly) in the HSL protein, respectively. The HSL gene can be considered as a candidate gene for fatness in pigs.

Long-term potentiation induced by nicotine in CA1 region of hippocampal slice is Ca(2+)-dependent

AIM

To observe the effects of Ca2+ on hippocampal long-term potentiation (LTP) induced by nicotine in CA1 region of rat hippocampal slice.

METHODS

Extracellularly recorded population spikes (PS) of the pyramidal cell layer in the hippocampal CA1 region in vitro.

RESULTS

Nicotine 1 mumol.L-1 induced LTP in the hippocampal CA1 region. It did not induce LTP in CA1 region when CA2+ was removed from artificial cerebrospinal fluid (ACSF). Nifedipine 1 and 10 mumol.L-1 partly inhibited LTP induced by nicotine, and thapsigargin 1 and 10 mumol.L-1 completely inhibited LTP induced by nicotine.

CONCLUSION

LTP induced by nicotine in hippocampal CA1 region is Ca(2+)-dependent. Both Ca2+ influx and Ca2+ release participate in the induction of LTP.