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Mammalian oocytes within Graafian follicles are arrested at prophase I of meiosis. C-type natriuretic peptide (NPPC), secreted by mural granulosa cells (MGCs), maintains oocyte meiotic arrest via binding to its cognate receptor natriuretic peptide receptor 2 (NPR2) and producing cyclic guanosine monophosphate (cGMP). NPR2 is most concentrated in the cumulus cells. In addition, cAMP, gap junction, inosine monophosphate dehydrogenase (IMPDH) and other important regulatory factors are also involved in meiotic arrest. Luteinizing hormone (LH) then rapidly decreases cGMP and induces oocyte meiotic resumption. In this paper, advances in the molecular mechanisms of meiotic arrest and LH-induced meiotic resumption were reviewed. This paper may provide new ideas for the prevention, diagnosis and treatment of related reproductive diseases.

Objective: To analyze the risk factors for metastasis of lymph nodes between sternocleidomastoid and sternohyoid muscle (LNSS) in papillary thyroid cancer (PTC). Methods: Papillary thyroid cancer patients with clinically positive lateral lymph node metastasis (cN1) who underwent surgery including LNSS dissection between May 1, 2013 and May 31, 2016 at the Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center were retrospectively studied. Logistic regression analysis was performed to evaluate possible clinicopathological factors related to LNSS metastasis. Results: In 85 patients, 54 patients (63.5%) showed LNSS in their surgical specimen, and 20 patients (23.5%) had pathologically positive LNSS metastasis. Patients with LNSS showed preoperatively higher levels of serum thyroid stimulating hormone (TSH) and thyroid peroxidase antibody (TPO-Ab) compared to patients only with fibrofatty tissues between sternocleidomastoid and sternohyoid muscle ( P <0.05), and they also displayed a higher proportion of multifocality in ipsilateral thyroid lobe ( P <0.05). Multi-factor analysis indicated that LNSS metastasis was correlated with original tumor size ( OR =1.819, 95% CI 1.050-3.850, P =0.002) and Level Ⅳ lymph node metastasis ( OR =2.190, 95% CI 1.132-2.334, P =0.005). Furthermore, the number of positive LNSS was tightly correlated to that of level Ⅳ lymph node metastasis( P <0.05). Conclusion: LNSS metastasis is occult but not quite rare in PTC. Patients with extensive lymph node metastasis in Level Ⅳhave a higher risk for metastasis of LNSS.

The study was aimed to investigate the mechanism of mannan-binding lectin (MBL) on bacterial lipopolysaccharide (LPS)-induced human peripheral blood monocyte-derived dendritic cell (DC) maturation. The monocytes were prepared from the peripheral blood of healthy adult volunteers. The immature dendritic cells (imDC) were induced by 5-day-culture in medium supplemented with rhGM-CSF and rhIL-4. FACS was used to investigate the interaction of MBL with imDC and the impact of MBL on LPS binding to imDC. ELISA and Western blot was used to analyze the interaction of MBL with soluble TLR4 ectodomain protein (sTLR4); Western blot was used to detect LPS-induced NF-κB translocation in imDC. The results showed that MBL could directly bind to imDC in the presence of calcium. sTLR4 protein or LPS could competitively inhibit the binding of MBL to imDC. ELISA and Western blot showed that MBL could evidently bind to sTLR4 protein in a concentration-dependent manner. FACS showed that MBL could competitively inhibit the binding of LPS to imDC by binding to imDC directly. Western blot showed that MBL decreased LPS-induced NF-κB translocation in imDC. It is concluded that MBL may competitively inhibit the binding of LPS to imDC by binding to TLR4 expressed on imDC, resulted in inhibition of LPS-induced DC maturation, suggesting that MBL can regulate DC maturation through ligand-binding. This study provides the good foundation to clarify the mechanism of MBL inhibiting the LPS-induced DC maturation.

Objective: To compare the long-term outcome of ligating the middle colic artery in radical surgical treatment of right hemicolon cancer., Methods: The operation safety, complications and short-term outcome between two groups of patients undergone either ligating the middle colic artery from its root (A group) or ligating the middle colic artery from its right branch (B group) in right hemicolectomy for colon cancer., Results: Between January 1981 and December 2004, 308 patients underwent radical right hemicolectomy in which 103 patients were treated by ligating the middle colic artery from its roots(Jan. 1996 to Dec. 2004, A group), and 205 patients via ligating the middle colic artery from the roots of its right branch(Jan. 1981 to Dec. 1995, B group). The complications were compared between the two groups(P>0.05). The mean follow-up time of A and B group were(50.1+/-7.2) months and(49.1+/-7.2) months respectively. Local recurrences of 1-year, 3-year and cumulative survival probability at the 60th month in group A were 1.9%, 13.6% and(78.3+/-3.4)% respectively, which were significantly better than 19.0%, 24.9% and(64.8+/-2.8)% in group B(P<0.05)., Conclusion: Ligating the middle colic artery from its root in right hemicolectomy can be performed safely and effectively, which is to be highly recommended in curative resection of right colon.

Deficiency of micronutrients, especially iron and zinc, has been a serious malnutrition problem worldwide in human health. Increasing Fe and Zn concentrations in grains by means of plant breeding is a sustainable, effective and important way to improve human mineral nutrition and health. However, little information on grain Fe and Zn concentrations in Chinese wheat genotypes is available. Therefore, to determine the nutrients status especially these of micronutrients in wheat grain is necessary and very useful. Two hundred sixty two genotypes were selected from the wheat mini-core collections, which contained 23090 wheat genotypes in China and represented 72.2% of total genetic variation. All 262 genotypes were grown in soils of similar geographical and climate location in order to minimize the environmental effect. After harvesting, the grains were washed with deionized water and dried (around 70 degrees C), then digested in HNO3 solution using a microwave accelerating reaction system (MARS). Nutrient concentrations in stock solution were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Remarkable genetic variations among grain nutrient concentrations (Fe, Mn, Cu, Zn, Mg, Ca, K and P ) in the tested genotypes were detected. The concentrations of Fe, Zn, Mn, Cu, Ca, Mg, K and P in wheat grain were in the ranges of 34.2-61.2, 26.3-76.0, 20.9-56.7, 3.4-9.8, 290-976, 1129-2210 mg x kg(-1); 0.34%-0.85% and 0.296%-0.580%, respectively. The corresponding average values were 45.1, 50.2, 37.9, 6.5, 515, 1772 mg x kg(-1), 0.55% and 0.451%, respectively. Significant positive correlations between micronutrients (Fe, Mn, Zn, and Cu) in wheat grains were detected, and the correlation coefficients were 0.395** (Fe and Mn), 0.424** (Fe and Zn), 0.574** (Fe and Cu), and 0.474** (Mn and Cu), respectively. However, no significant difference was found in grain nutrient concentrations between spring-wheat and winter-wheat genotypes. This study provides valuable and important information for breeding wheat genotypes which are enriched with minerals in grains, especially Fe and Zn

Objective: To explore the effects of the simultaneous activation of liver X receptor (LXR) and peroxisome proliferator-activated receptor alpha (PPARalpha) on bile acid biosynthesis in rats., Methods: Totally 36 male SD rats were divided into three groups with 12 rats in each group: control group, high cholesterol (HC) group, and high cholesterol + fenofibrate (HC + FENO) group. Total bile acids (serum bile acids plus fecal bile acids) level was assayed. The levels of mRNA for peroxisomal palmitoyl-CoA oxidase (Acox1), LXR, cholesterol 7alpha-hydroxylase (CYP7A1), D-bifunctional protein (DBP), trihydroxycoprostanoyl-CoA oxidase (Acox2), sterol 12alpha-hydroxylase (CYP8B1), and sterol 27-hydroxylase (CYP27A1) in liver were detected by RT-PCR., Results: Total bile acid level was significantly higher in HC + FENO group than in HC group (P < 0.01), and both were significantly higher than that in control group (P < 0.01). Compared with HC group, the mRNA expression of Acox1 and DBP was significantly higher in HC + FENO group (P < 0.01), but no statistical differences was found between HC group and control group. The mRNA levels of LXR and CYP7A1 in HC + FENO group and HC group were not significantly different but were both significantly higher than that in control group (P < 0.01, P < 0.05). No changes were observed in Acox2, CYPSB1, and CYP27A1 mRNA levels among these three groups., Conclusion: Simultaneous activation of LXR and PPARalpha can increase of CYP7A1 and DBP mRNA exDression and thus accelerates the biosynthesis of bile acid.

Objective: To investigate the expression of Ezrin in gastric cancer, its role in tumor metastasis., Methods: Ezrin expression in tumor tissues from 90 gastric cancer cases and in normal gastric mucosa from 12 cases with benign disease was examined by immunohistochemical staining. Ezrin expression in gastric cancer cell lines was also detected by Western blot, and in vitro invasion assay was used to examine the invasive ability of the cell lines., Results: The expression rate of Ezrin was significantly higher in gastric cancer tissues than that in normal tissues (P< 0.05), and significantly correlated with lymph node metastasis (P< 0.05). Western blot showed that MKN-45 cell line had the highest expression of Ezrin among 5 gastric cancer cells. MKN-45 possessed highest invasion ability., Conclusion: Ezrin expression is up-regulated, and may be associated with lymph node metastasis in gastric cancer.

Objective: To determine the physiological role of D-bifunctional protein (DBP) in bile acid biosynthesis through investigating the effect of increasing activity of DBP on bile acid biosynthesis., Methods: Twenty male Wistar rats were divided into two groups: diethylhexyl phthalate (DEHP) group (n = 10) and control group (n = 10). Serum triglyceride, total cholesterol, hepatic DBP activity, and fecal bile acids were assayed. The mRNA levels of hepatic peroxisome proliferator-activated receptor alpha (PPARalpha), DBP, and cholesterol 7alpha-hydroxylase (CYP7A1) were detected by RT-PCR., Results: Compared with control group, serum triglyceride level was decreased significantly and PPARalphamRNA level was increased significantly in DEHP group (P < 0.01). Together with a sharp induction of DBP mRNA expression and DBP activity in DEHP group (P < 0.01), the levels of CYP7A1 mRNA and fecal bile acids were significantly increased by 1.9 times and 1.6 times respectively compared to control group (P < 0.01). There was a significantly positive correlation between DBP mRNA level or DBP activity and CYP7A1 mRNA level (r = 0.89, P < 0.01; r = 0.95, P < 0.01)., Conclusion: The up-regulation of DBP mRNA and activity in liver can result in the increase in CYP7A1 mRNA expression and bile acid biosynthesis, suggesting that DBP may be involved in bile acid biosynthesis together with CYP7A1.

Aim: To study the effects of caspases on cerebromicrovascular endothelial cell apoptosis induced by hypoxia in vitro., Methods: The cultured bovine cerebromicrovascular endothelial cells were exposed to NaCN in glucose-free medium. Cell viability was determined by trypan blue staining. Cell apoptosis was defined by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) and flow cytometry. The expression of caspase-3 was detected by immunocytochemical method. Four caspase inhibitors were used to validate the effect of caspases on cell apoptosis., Results: NaCN in glucose-free medium initiated cerebromicrovascular endothelial cell injury markedly and typical apoptotic cells were found in this model. The expression of caspase-3 increased significantly. Four caspase inhibitors decreased the number of injured cells. Selective inhibitor of caspase-1 and -6 reduced expression of caspase-3 significantly., Conclusion: The results suggest that caspases family plays an important role in cerebromicrovascular endothelial cell apoptosis induced by NaCN and caspase-3 acts on the downstream of caspase-1 and -6 in protease cascade action to induce apoptosis.

Aim: To study the effect of puerarin on vascular endothelial cells apoptosis induced by chemical hypoxia-ischemia in vitro., Methods: The chemical hypoxia-ischemia model was performed by treating cultured bovine aortic endothelial cells (BAECs) with NaCN in glucose-free medium. Cell viability was determined by trypan blue staining. Cell apoptosis was defined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), flow cytometry and Hoechst 33342 staining. The expression of Caspase-3 in endothelial cells was detected by immunocytochemical method., Results: Chemical hypoxia-ischemia was shown to initiate bovine aortic endothelial cell apoptosis. Puerarin (0.5-3 mmol.L-1) was found to inhibit endothelial cell apoptosis effectively, and reduce the expression of Caspase-3 significantly., Conclusion: Puerarin can protect apoptotic endothelial cells induced by chemical hypoxia-ischemia markedly and the effect was performed partly by decreasing Caspase-3 expression.