Association between polymorphisms in transforming growth factor-ß1 and sporadic Alzheimer's disease in a Chinese population.

Alzheimer's disease (AD) is the most common neurodegenerative disorder of the brain. It causes the slow progressive loss of cognitive functions that ultimately leads to dementia and death in the elderly. The etiology and mechanism of late-onset AD (LOAD) are poorly understood, and genetic factors might play an important role in the development of AD. The aim of this study was to investigate the association between common polymorphisms in TGF-ß1 with LOAD in a Chinese Han population. Two single nucleotide polymorphisms in TGF-ß1 (rs1800469 and rs1982073) were genotyped in 202 patients with sporadic LOAD and 225 control subjects using polymerase chain reaction restriction fragment length polymorphism. Our results showed that rs1800469 in TGF-ß1 were significantly associated with LOAD. The frequencies of the AC genotypes of rs1800469 were significantly higher in the LOAD patients than in the control subjects (42.5% vs 28.6%; P = 0.001). The minor allele (C) frequency was significantly higher in patients with LOAD than in control subjects (30.7% vs. 21.0%; P = 0.001). The genotypes and allele of rs1982073 in TGF-ß1 were also significantly associated with LOAD. The frequency of the TG genotype of rs1982073 was significantly higher in the LOAD patients than in the control subjects (38.1% vs. 27.1%; P = 0.013). The minor allele (G) frequency was significantly higher in patients with LOAD than in control subjects (22.2% vs. 16.7%; P = 0.032). These results suggest that common variants in TGF-ß1 might contribute to the development of LOAD in the Chinese population.

Progesterone elevation on the day of human chorionic gonadotropin administration adversely affects the outcome of IVF with transferred embryos at different developmental stages.

BACKGROUND: The effect of progesterone elevation (PE) on the day of human chorionic gonadotropin (hCG) administration on the pregnancy outcomes of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles is a matter of ongoing debate. The replacement of cleavage-stage embryos with blastocyst-stage embryos for transfer was proposed to avoid the possible impairment of PE in fresh cycles. This study aimed to assess the association between PE on the day of human chorionic gonadotropin (hCG) administration and clinical pregnancy rates (CPRs) in IVF/ICSI cycles with embryos transferred at different developmental stages (cleavage and blastocyst). Moreover, a secondary aim was to determine the thresholds at which PE has a detrimental effect on CPRs. METHODS: This single-center retrospective cohort study included more than 10,000 patients undergoing day 3 cleavage-stage embryo transfer (ET) and 1146 patients undergoing day 5 blastocyst-stage embryo transfer (ET) using gonadotropin and GnRH agonist for controlled ovarian stimulation. RESULTS: Serum PE was inversely associated with CPRs in both cleavage- and blastocyst-stage ET cycles. In the day 3 ET cycles, CPRs (progesterone levels < 0.5 ng/ml, 49.2 %) significantly declined when the progesterone concentration reached 1.0 ng/ml (45.5 %) and decreased further when the progesterone concentration increased to 1.5 ng/ml (36.2 %). In the day 5 blastocyst-stage ET cycles, patients with serum progesterone levels ≥1.75 ng/ml had significantly lower CPRs (31.3 % VS. 41.4 %, p < 0.001) compared to patients with serum progesterone levels <1.75 ng/ml. The negative association of PE with CPRs was noted in both ET groups, even after adjusting for confounders. Furthermore, the developmental stage of the transferred embryos was not linked to the effect of PE on CPRs because the interaction between the developmental stage of the transferred embryos and PE was not significant. CONCLUSIONS: PE on the day of hCG administration is associated with decreased CPRs in GnRH agonist IVF/intracytoplasmic sperm injection (ICSI) cycles regardless of the developmental stage of the transferred embryos (cleavage versus blastocyst stage).

Role of PAFAH1B1 in human spermatogenesis, fertilization and early embryonic development.

Spermatogenesis, fertilization and subsequent embryonic development are complex processes that require tight regulation. The PAFAH1B1 gene plays important roles in these reproductive events in mice, but its expression and roles in human reproduction have not been investigated. Expression analysis of testicular tissue by reverse transcription quantitative PCR and immunohistochemistry revealed varied expression levels among samples of different spermatogenic abilities (as assessed by the Johnsen score), with protein expression restricted to spermatogonia, spermatocytes and spermatids. Immunofluorescence on spermatozoa showed expression over the acrosome and midpiece regions of ejaculated samples, whereas a high proportion of percutaneous epididymal sperm aspiration-derived spermatozoa showed expression restricted to the midpiece. Analysis for PAFAH1B1 mRNA also revealed different expression levels among unfertilized oocytes, zygotes, cleavage stage embryos and blastocysts, with protein localized at the membrane level in oocytes and zygotes, and gradually distributing within the cytoplasm of cleavage stage embryos and blastocysts. Interestingly, microinjection of PAFAH1B1 siRNA into zygotes significantly (P = 0.024) increased fragmentation formation rates in subsequent embryonic development stages. Altogether, these are the first results to support a role for PAFAH1B1 in human spermatogenesis and early embryonic development.

Blocking epidermal growth factor receptor attenuates reactive astrogliosis through inhibiting cell cycle progression and protects against ischemic brain injury in rats.

Excessive astrogliosis is a major impediment to axonal regeneration in CNS disorders. Overcoming this inhibitory barrier of reactive astrocytes might be crucial for CNS repair. Up-regulation and activation of epidermal growth factor receptor (EGFR) has been shown to trigger quiescent astrocytes into reactive astrocytes in response to several neural injuries. In this study, we investigated the effects of EGFR blockade in cultured astrocytes exposure to oxygen-glucose deprivation/reoxygenation (OGD/R) and in the rat middle cerebral artery occlusion (MCAO) model. Astrocytes in primary culture were used for OGD/R model and adult male Sprague-Dawley rats were used for MCAO model. Cell cycle progression of astrocytes in vitro was studied by flow cytometric analysis. Expression of phosphorylated epidermal growth factor receptor (p-EGFR), glial fibrillary acidic protein (GFAP), and cell proliferation-related molecules in vitro and in vivo were evaluated by immunostaining and western blot analysis. Neuronal apoptosis after MCAO was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Neurologic scores and infarct volumes post-ischemia were assessed in the rat MCAO model. Astrocytes became activated in the cultured astrocytes exposure to OGD/R and in the rat brain after MCAO, accompanied with phosphorylation of EGFR. EGFR blockade significantly decreased expression of p-EGFR, inhibited cell cycle progression of astrocytes, and reduced reactive astrogliosis in vitro and in vivo. EGFR inhibition also reduced infarct volumes and improved neurologic scores of rats after MCAO. Our findings indicated that blocking EGFR pathway might attenuate reactive astrogliosis through inhibiting cell cycle progression and protect against ischemic brain injury in rats.

Body mass index effects sperm quality: a retrospective study in Northern China.

Excess weight and obesity have become a serious problem in adult men of reproductive age throughout the world. The purpose of this retrospective study was to assess the relationships between body mass index and sperm quality in subfertile couples in a Chinese Han population. Sperm analyses were performed and demographic data collected from 2384 male partners in subfertile couples who visited a reproductive medical center for treatment and preconception counseling. The subjects were classified into four groups according to their body mass index: underweight, normal, overweight, and obese. Of these subjects, 918 (38.3%) had a body mass index of >25.0 kg m-0 2 . No significant differences were found between the four groups with respect to age, occupation, level of education, smoking status, alcohol use, duration of sexual abstinence, or the collection time of year for sperm. The results clearly indicated lower sperm quality (total sperm count, sperm concentration, motile sperm, relative amounts of type A motility, and progressive motility sperm [A + B]) in overweight and obese participants than in those with normal body mass index. Normal sperm morphology and sperm volume showed no clear difference between the four groups. This study indicates that body mass index has a negative effect on sperm quality in men of subfertile couples in a Northern Chinese population. Further study should be performed to investigate the relationship between body mass index and sperm quality in a larger population.

Blastocoele expansion degree predicts live birth after single blastocyst transfer for fresh and vitrified/warmed single blastocyst transfer cycles.

OBJECTIVE: To evaluate the independent effects of the degree of blastocoele expansion and re-expansion and the inner cell mass (ICM) and trophectoderm (TE) grades on predicting live birth after fresh and vitrified/warmed single blastocyst transfer. DESIGN: Retrospective study. SETTING: Reproductive medical center. PATIENT(S): Women undergoing 844 fresh and 370 vitrified/warmed single blastocyst transfer cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Live-birth rate correlated with blastocyst morphology parameters by logistic regression analysis and Spearman correlations analysis. RESULT(S): The degree of blastocoele expansion and re-expansion was the only blastocyst morphology parameter that exhibited a significant ability to predict live birth in both fresh and vitrified/warmed single blastocyst transfer cycles respectively by multivariate logistic regression and Spearman correlations analysis. Although the ICM grade was significantly related to live birth in fresh cycles according to the univariate model, its effect was not maintained in the multivariate logistic analysis. In vitrified/warmed cycles, neither ICM nor TE grade was correlated with live birth by logistic regression analysis. CONCLUSION(S): This study is the first to confirm that the degree of blastocoele expansion and re-expansion is a better predictor of live birth after both fresh and vitrified/warmed single blastocyst transfer cycles than ICM or TE grade.

Impact of oxygen concentrations on fertilization, cleavage, implantation, and pregnancy rates of in vitro generated human embryos.

The aim of the present study was to determine the impact of oxygen concentration during in vitro culture of human oocytes and embryos on fertilization, cleavage, implantation, pregnancy, multiple gestation and abortion rates. Women 20-48 years old presenting for infertility treatment and accounting for 3484 in vitro fertilization/intracytoplasmic sperm injection cycles were included in the study. Oocytes/embryos were randomly allocated to be incubated under three different oxygen tension environments: (1) 20% O2 in air; (2) initially 20% O2 in air, followed on day 2 (2-4 cells stage) by 5% CO2, 5% O2 and 90% N2; and (3) 5% CO2, 5% O2 and 90% N2 throughout. Interestingly, IVF-derived embryos cultured in 5% O2 yielded higher rates of fertilization and implantation as compared to those incubated in 20% O2 (P < 0.05). Conversely, embryos in 20% O2 yielded higher rates of fertilization, high quality embryo and implantation than those in the 20%-5% O2 group (P < 0.05). Moreover, ICSI-derived embryos cultured in 20% O2 resulted in lower rates of cleavage as compared to those from the 20%-5% O2 group (P < 0.05). These results are consistent with in vitro and subsequent in vivo embryo development being more susceptible to O2 tension fluctuations rather than the degree of O2 tension itself during culture.

Association between single-nucleotide polymorphisms in interleukin-12A and risk of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is characterized by airflow obstruction due to chronic bronchitis, emphysema, and/or disease of small airways. It has been reported that the genetic variation may play a role in the development and severity of COPD. The purpose of this study was to investigate whether single-nucleotide polymorphisms (SNP) in interleukin (IL)-12A and IL-12B were associated with COPD in a Chinese population. The IL-12A rs2243115 and IL-12B rs3212227 polymorphisms were genotyped by performing polymerase chain reaction-restriction fragment length polymorphism in 298 patients with COPD and 346 healthy controls. We observed that the frequencies of GT and GT+GG of IL-12A rs2243115 were significantly different from TT in the COPD group and the control group (GT vs. TT: odds ratio [OR]=2.35, 95% confidence interval [CI]=1.55-3.57, p<0.001; GT+GG vs. TT: OR=2.46, 95% CI=1.63-3.71, p<0.001). These data suggest that the IL-12A rs2243115 polymorphism may contribute to genetic susceptibility to COPD in a Chinese population.

No association between vitamin D receptor polymorphisms and coronary artery disease in a Chinese population.

The clinical features suggest that genetic factors may have a strong influence on susceptibility to coronary artery disease (CAD). The aim of this study was to investigate the association between FokI (rs2228570) and BsmI (rs1544410) of the vitamin D receptor (VDR) gene polymorphisms and patients with CAD in a Chinese population. One hundred and fifty-two CAD patients and 212 healthy controls were genotyped for the FokI and BsmI polymorphisms in VDR gene using polymerase chain reaction-restriction fragment length polymorphism. No significant differences were observed in the genotype and allele frequencies of the FokI and BsmI polymorphisms between the cases and controls (For FokI: odds ratio = 1.11, 95% confidence interval 0.83-1.50; for BsmI: odds ratio = 0.74, 95% confidence interval 0.44-1.23). There was no significant difference in the genotype distribution or the allele frequencies of VDR FokI and BsmI between two groups in a Chinese population.