A simple enzyme-assisted cascade amplification strategy for ultrasensitive and label-free detection of DNA.

A simple fluorescence biosensor is developed based on the enzyme-assisted cascade amplification strategy. The amplification system consists of a hairpin-structure DNA (H-DNA) and exonuclease III. The target DNA can hybridize with the H-DNA and initiate exonuclease III-assisted target recycling amplification to generate abundant G-rich DNA (G-DNA). One region of G-DNA is designed to possess the same sequence as target DNA. Thus, the G-DNA can also hybridize with H-DNA and initiate the digestion of H-DNA. The cascade strategy in this amplification system causes the concentration of G-DNA to grow exponentially. The fluorescence intensity of N-methylmesoporphyrin IX (NMM) is highly enhanced due to the formation of G-quadruplex configuration. Under optimal conditions, the cascade system could achieve an admirable sensitivity with a detection limit of 52 fM for HIV DNA, and guarantees a satisfactory specificity. Moreover, the cascade system could be implemented for other target DNA detections by substituting the recognition region of the H-DNA. In this way, a detection limit of 65 fM for HBV DNA could be achieved by the cascade system. The target DNA analysis in a real serum sample further indicates that this biosensor has potential for future application in clinical diagnosis. Graphical abstract A simple and label-free cascade amplification strategy is developed by exploiting hairpin DNA and EXO III for sensitive DNA detection.

A sensitive aptasensor based on molybdenum carbide nanotubes and label-free aptamer for detection of bisphenol A.

To specifically and sensitively identify bisphenol A (BPA) with a simple and rapid method is very important for food safety. Using an anti-BPA aptamer and Mo2C nanotubes, we developed a label-free and low-background signal biosensor for BPA detection. The anti-BPA aptamer drastically increased the fluorescence signal of N-methylmesoporphyrin IX under an assistance of Help-DNA. Additionally, BPA can interact with the anti-BPA aptamer and switch its conformation to prevent the formation of a G-quadruplex, resulting in fluorescence quenching. Simultaneously, Mo2C nanotubes can reduce the background signals due to the adsorption of Help-DNA on their surface. This method shows a linear range of 2-20 nM with a detection limit of 2 nM for detecting BPA. This label-free BPA aptasensor with low background signal is inexpensive, easy to use, and can be applied to determine BPA in real water samples. Graphical Abstract A low-background and label-free biosensor was designed based on Mo2C nanotubes and aptamer for BPA detection.

Glutathione-mediated mesoporous carbon as a drug delivery nanocarrier with carbon dots as a cap and fluorescent tracer.

This work describes a novel and general redox-responsive controlled drug delivery-release nanocarrier with mesoporous carbon nanoparticles (MCNs) gated by customized fluorescent carbon dots (CDs). The modification of MCNs with a disulfide unit enables the system to be sensitive to intracellular glutathione (GSH). The CDs anchoring onto the surface of the MCNs via an electrostatic interaction block the mesopores and thus prevent the leakage of doxorubicin (DOX) loaded inside the channel of the MCNs. Upon the addition of GSH at the physiological environment, the integrity of the system is disrupted due to the dissociation of the disulfide bond; meanwhile stripping the CDs opens the gate and thus triggers the rapid release of the encapsulated DOX. The fluorescence of the CDs is quenched/'turned off' when linking to the MCNs, while it is restored/'turned on' when detaching the CDs from the surface of the MCNs. Thus the fluorescent CDs serve as both a controllable drug release gatekeeper and a fluorescent probe for the visualization of the drug delivery process. By combining these inherent capabilities, the present drug delivery system may be a promising route for designing custom-made visual controlled-release nanodevices specifically governed by in situ stimulus in the cells.

The study of double-network carboxymethyl chitosan/sodium alginate based cryogels for rapid hemostasis in noncompressible hemorrhage.

Developing an injectable hemostatic dressing with shape recovery and high blood absorption ratio for rapid hemostasis in noncompressible hemorrhage maintains a critical clinical challenge. Here, double-network cryogels based on carboxymethyl chitosan, sodium alginate, and methacrylated sodium alginate were prepared by covalent crosslinking and physical crosslinking, and named carboxymethyl chitosan/methacrylated sodium alginate (CM) cryogels. Covalent crosslinking was achieved by methacrylated sodium alginate in the freeze casting process, while physical crosslinking was realized by electrostatic interaction between the amino group of carboxymethyl chitosan and the carboxyl group of sodium alginate. CM cryogels exhibited large water swelling ratios (8167 ± 1062 %), fast blood absorption speed (2974 ± 669 % in 15 s), excellent compressive strength (over 160 kPa for CM100) and shape recovery performance. Compared with gauze and commercial gelatin sponge, better hemostatic capacities were demonstrated for CM cryogel with the minimum blood loss of 40.0 ± 8.9 mg and the lowest hemostasis time of 5.0 ± 2.0 s at hemostasis of rat liver. Made of natural polysaccharides with biocompatibility, hemocompatibility, and cytocompatibility, the CM cryogels exhibit shape recovery and high blood absorption rate, making them promising to be used as an injectable hemostatic dressing for rapid hemostasis in noncompressible hemorrhage.

Selective isolation of hemoglobin by use of imidazolium-modified polystyrene as extractant.

Ionic liquids have attracted much attention in the analysis of a variety of species. The functional groups in ionic liquids can result in highly efficient separation and enrichment and, because of their typical lack of volatility, they are environmentally benign. We grafted imidazole cations onto the surface of chloromethyl polystyrene, denoted PS-CH2-[MIM](+)Cl(-), and this modified polymer was used to selectively extract the protein hemoglobin (Hb). The prepared extractant PS-CH2-[MIM](+)Cl(-), containing 2 mmol immobilized imidazole groups per gram polymer, was characterized by FT-IR, surface charge analysis, and elemental analysis. The adsorption efficiency was 91%. The adsorption capacity of the PS-CH2-[MIM](+)Cl(-) for Hb was 23.6 µg mg(-1), and 80% of the retained Hb could be readily recovered by use of 0.5% (m/v) aqueous sodium dodecyl sulfate (SDS) solution as eluate. The activity of the eluted Hb was approximately 90%. The prepared imidazole-containing solid phase polymer was used for direct adsorption of Hb without use of any other solid matrix as support of the ionic liquid. The material was used in practice to isolate Hb from human whole blood.

How to deal with fluid in the endometrial cavity during assisted reproductive techniques.

PURPOSE OF REVIEW: Patients with endometrial cavity fluid (ECF) in assisted reproductive techniques (ARTs) are poor in prognosis. This review presents the research development of ECF during ARTs, particularly in treatment. RECENT FINDINGS: ECF patients with or without tubal infertility may represent a different clinical entity. ECF impairs the ART outcome in tubal factor, but not polycystic ovarian syndrome, patients. Actually, it was tubal infertility, not only hydrosalpinx, that was related to the development of ECF. Both appearance time and accumulation amount of ECF are critical in the impact of ECF on the ART outcome. Since excessive ECF (equal to or higher than 3.5 mm in the anterior-posterior diameter) usually had a negative impact on the ART outcome, postponing embryo transfer should be considered. A nonexcessive ECF usually disappeared by the time of embryo transfer. The routine embryo transfer in these ECF patients could yield the same ART outcome as in patients without ECF. If a nonexcessive ECF persisted until the day of embryo transfer, particularly in patients with nontube infertility, transvaginal sonographic aspiration could be an alternative of treatment. SUMMARY: The treatment of ECF during ARTs should be individual according to the causes, appearance time and accumulation amount of ECF.

Highly elevated serum CA-125 levels in patients with non-malignant gynecological diseases.

PURPOSES: To identify patients with highly elevated serum CA-125 levels and analyze their clinical characteristics. METHODS: Patients with non-malignant gynecologic disease (NMGDs, n = 41), in whom serum CA-125 levels were over 1,000 IU/ml were retrospectively enrolled in the study. Seventy-one patients with epithelial ovarian cancer (EOC), in whom, serum CA-125 levels were over 1,000 IU/ml were included as the comparison group. Clinical parameters were compared between the two groups. RESULTS: In NMGDs group, 43.90% of the patients had endometriosis. The median of serum CA-125 level in NMGDs was much lower than that of EOC subjects (P < 0.001). Compared to EOC group, the patients in NMGDs group were much younger (P < 0.001) and had fewer histories of pelvic masses (P < 0.001) but had more clinical complaints such as acute abdominal symptoms (P < 0.001) and/or abnormal vaginal bleeding (P = 0.022). Clinical progresses of these two groups were correlated with changes of serum CA-125 levels by follow-up for up to 386 days. CONCLUSIONS: High levels of serum CA-125 were found not only in the EOC, but also in some NMGDs, especially in the reproductive patients with complaints of acute abdomen symptoms or abnormal vaginal bleeding.

The associated factors to endometrial cavity fluid and the relevant impact on the IVF-ET outcome.

BACKGROUND: Endometrial cavity fluid (ECF) is a fluid accumulation within the endometrial cavity. The significance of ECF remains unclear during the program of in vitro fertilization-embryo transfer (IVF-ET). The aim of the present study was to investigate the associated factors to ECF, visualized through ultrasound at the day of oocyte retrieval, and the relevant impact on the outcome of IVF-ET. METHODS: From the clinical data of 1557 infertility patients for IVF-ET program, 46 ECF patients were retrospectively selected as the ECF group; and another 134 patients with a bilateral salpingectomy and without ECF, selected as the control group. The demographics and the outcome of IVF-ET were compared between the two groups. RESULTS: The incidence of ECF was 2.95% (46/1557). Over half (28/46, 60.87%) of ECF patients had tubal infertility. Only 12 Of 46 ECF patients (26.09%) had visible hydrosalpinx on ultrasonography before ovarian stimulation. The cycle cancellation rate (4/46, 8.69%) of ECF group was not significantly higher than that of the control group (6/134, 4.48%; P > 0.05). Reasons for cycle cancellation in both groups were all the high risk of ovarian hyperstimulation syndrome (OHSS). No significant difference was found in clinical pregnancy rate between the patients with their ECF <3.5 mm in the anterior-posterior diameter (APD) and the control group (35.48% versus 30.47%; P > 0.05). No clinical pregnancy was found among those patients with their ECF equal or higher 3.5 mm in APD. CONCLUSIONS: It was tubal infertility, not hydrosalpinx, which was related to the development of ECF. Excessive ECF (equal or higher 3.5 mm in APD) at the day of oocyte retrieval would have a negative impact on the outcome of IVF-ET.

Decreased expression of endometrial vessel AQP1 and endometrial epithelium AQP2 related to anovulatory uterine bleeding in premenopausal women.

OBJECTIVE: Aquaporins (AQPs) may be involved in the occurrence of abnormal uterine bleeding as the mediators between ovarian steroids and cyclic endometrial changes. The aim of the present study was to investigate the characteristics of endometrial AQPs in women with anovulatory uterine bleeding and explore the relationship between endometrial AQPs and ovarian steroids. DESIGN: Sixty-one women with premenopausal anovulatory uterine bleeding and 108 women with normal cycles were involved in this study. Endometrial biopsies were obtained from the women with anovulatory uterine bleeding and normal control women. Serum estradiol and progesterone concentrations were measured with enzyme-linked immunosorbent assay on the same day as an endometrial biopsy was performed. AQP1 and AQP2 mRNA expression was evaluated using reverse-transcriptase polymerase chain reaction. Immunohistochemistry was used to localize AQP1 and AQP2 in the endometrium, and their expression was quantified by an image analysis/measuring system. RESULTS: AQP1 was located in the endothelium of small vessels, whereas AQP2 was mainly found in luminal and glandular epithelium. The expression levels of AQP1 and AQP2 mRNA and protein were higher in the secretory phase than those in the proliferative phase (P < 0.01) in normal endometrium, and their expression was related to serum steroid hormones (P < 0.01). However, the expression of AQP1 and AQP2 decreased in the endometrium in anovulatory uterine bleeding comparing with normal endometrium (P < 0.01). The correlation between AQP expression and ovarian steroids vanished (P > 0.05) in anovulatory uterine bleeding. CONCLUSIONS: Our findings indicate that cyclic expression of endometrial AQP1/AQP2 correlated with steroid hormone levels may be essential to normal endometrial function and decreased AQP1/AQP2 expression in endometrial vessels or epithelium may be involved in the occurrence of anovulatory uterine bleeding.

Impacts of different methods of conception on the perinatal outcome of intrahepatic cholestasis of pregnancy in twin pregnancies.

Twin pregnancies have a higher prevalence of intrahepatic cholestasis of pregnancy (ICP) than single pregnancies. It is unknown whether in vitro fertilization-embryo transfer (IVF-ET) influences the fetal outcomes in twin pregnancies complicated by ICP. This study aimed to explore the impact of IVF-ET on the perinatal outcomes of ICP in twin pregnancy. Clinical data from 142 twin pregnant women complicated with ICP were retrospectively analyzed, including 51 patients who conceived through IVF-ET (IVF group) and 91 patients with spontaneous conception (SC group). Several biochemical indicators and perinatal outcomes were analyzed. Compared to the SC group, the IVF group had a higher incidence of early-onset ICP (P = 0.015) and more frequent clinical symptoms (P = 0.020), including skin pruritus, skin scratch, and jaundice. Furthermore, the IVF group had higher rates of neonatal asphyxia (IVF vs. SC, 9.80% vs. 1.10%, P = 0.023) and premature delivery (IVF vs. SC, 96.08% vs. 83.52%, P = 0.027) compared to the SC group. The IVF-conceived twin pregnancy group had a higher risk of early-onset ICP and suffered from clinical symptoms and poor perinatal outcomes.

Autonomous DNA nanomachine based on cascade amplification of strand displacement and DNA walker for detection of multiple DNAs.

DNA can be modified to function as a scaffold for the construction of a DNA nanomachine, which can then be used in analytical applications if the DNA nanomachine can be triggered by the presence of a diagnostic DNA or some other analyte. We herein propose a novel and powerful DNA nanomachine that can detect DNA via combining the tandem strand displacement reactions and a DNA walker. Three different DNA sensing platforms are described, where the whole DNA machine was constructed on a gold electrode (GE). This cascade multiple amplification strategy exhibited an excellent sensitivity. Under optimal conditions, the electrochemical sensor could achieve a detection limit of 36 fM with a linear range from 50 to 500 fM. In particular, the electrochemical sensor could easily distinguish the base mutations. More interestingly, the DNA nanomachine could be used to construct analog AND and OR logic gates. We demonstrate that electrochemical signals generated from the different input combinations can be used to distinguish multiple target DNAs. The practical applicability of the present biosensor is demonstrated by the detection of target DNA in human serum with satisfactory results, which holds great potential for a future application in clinical diagnosis.

DNA-fueled target recycling-induced two-leg DNA walker for amplified electrochemical detection of nucleic acid.

Taking advantage of the homogeneous and heterogeneous electrochemical biosensors, a simple, sensitive, and selective electrochemical biosensor is constructed by combining entropy-driven amplification (EDA) with DNA walker. This electrochemical biosensor realizes the biorecognition and EDA operation in homogeneous solution, which is beneficial to improve the recognition and amplification efficiency. A two-leg DNA walker generated by EDA can walk on the surface of gold electrode for cleaving the immobilized substrate DNA and releasing the electroactive labels, giving rise to a significant decrease of the electrochemical signal. The immobilization of the electroactive labels ensures the reproducibility and reliability of the biosensor. The present cascade amplification assay can be applied to detect target DNA with a detection limit of 0.29 fM, and base mutations can be easily distinguished. Moreover, the proposed electrochemical biosensor shows a satisfactory performance for the detection of target DNA in human serum. Thus, the novel electrochemical biosensor holds promising potential for a future application in disease diagnosis.

[Expression of cyclin B1 and cyclin-dependent kanasel in ectopic and eutopic endometrium tissues of patients with endometriosis].

OBJECTIVE: To investigate the possible roles of cyclin B1 and cyclin-dependent kanase1 cyclin-dependent kanase1 play in the pathogenesis and development of endometriosis and their association with the ovarian hormones. METHODS: Twenty-nine specimens of ectopic endometrium tissues and 20 specimens of eutopic endometrium tissues were obtained from 29 patients with endometriosis, aged 24 approximately 46. Thirty specimens of endometrium form 30 women without endometriosis were used as controls. The intracellular location of cyclin B1 and Cdc2 was detected by microscopy. Western blotting, RT-PCR, and immunohistochemistry were employed to examine the mRNA expression and protein expression of cyclin B1 and Cdc2. Serum estrogen and progestogen were detected. RESULTS: The expression level of cyclin B1 in the ectopic endometrium from the women with endometriosis was significantly higher than that in the ectopic endometrium tissues from the women with and without endometriosis (both P < 0.05). No significant difference was found between the expression level of cyclin B1 in the ectopic endometrium tissues from the women with and without endometriosis (both P > 0.05). The Cdc2 expression levels were not significantly different among th3 3 groups and the proliferative and secretary stage of endometrium (all P > 0.05). Cyclin B1 expression level was positively correlated with the serum estrogen level, and negatively correlated with the serum progestogen level, and Cdc2 expression was not correlated with the serum sex hormone levels. CONCLUSION: The expression of cyclin B1 in the ectopic endometrium is higher than normal. Cyclin B1 may be involved in the proliferation of endometrium in endometriosis.

[Women with poor response to ovarian stimulation have increased follicular bone morphogenetic protein-15 levels].

OBJECTIVE: To evaluate the levels of bone morphogenetic protein-15 (BMP-15) in human follicular fluid (FF) and its association with response to ovarian stimulation. METHODS: Western blotting was performed to determine the levels of BMP-15 in FF obtained from follicle aspirates in 70 patients undergoing IVF treatment. According to the response to ovarian stimulation the patients were divided into poor responder group and normal responder group. RESULT: BMP-15 levels in FF of poor responders were significantly higher than those in normal responders (1.01 +/- 0.34 vs 0.77 +/- 0.24, P<0.01). CONCLUSION: Increased levels of BMP-15 in FF may be associated with poor response to ovarian stimulation.

A novel electrochemical biosensor based on polyadenine modified aptamer for label-free and ultrasensitive detection of human breast cancer cells.

Simple, rapid, sensitive, and specific detection of cancer cells plays a pivotal role in the diagnosis and prognosis of cancer. A sandwich electrochemical biosensor was developed based on polyadenine (polydA)-aptamer modified gold electrode (GE) and polydA-aptamer functionalized gold nanoparticles/graphene oxide (AuNPs/GO) hybrid for the label-free and selective detection of breast cancer cells (MCF-7) via a differential pulse voltammetry (DPV) technique. Due to the intrinsic affinity between multiple consecutive adenines of polydA sequences and gold, polydA modified aptamer instead of thiol terminated aptamer was immobilized on the surface of GE and AuNPs/GO. The label-free MCF-7 cells could be recognized by polydA-aptamer and self-assembled onto the surface of GE. The polydA-aptamer functionalized AuNPs/GO hybrid could further bind to MCF-7 cells to form a sandwich sensing system. Characterization of the surface modified GE was carried out by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) using Fe(CN)63-/4- as a redox probe. Under the optimized experimental conditions, a detection limit of 8 cellsmL-1 (3σ/slope) was obtained for MCF-7 cells by the present electrochemical biosensor, along with a linear range of 10-105 cellsmL-1. By virtue of excellent sensitivity, specificity and repeatability, the present electrochemical biosensor provides a potential application in point-of-care cancer diagnosis.

Aquaporin-2 expression in human endometrium correlates with serum ovarian steroid hormones.

The aim of the present study was to examine the expression of aquaporin-2 (AQP2), a member of the water channel family aquaporins (AQPs), in human uterine endometrium and its modulation of ovarian steroid hormone at the proliferative and secretory phases. Western blot, immunohistochemistry, and RT-PCR were employed in the present study. Western blot revealed a 29-kDa band that represented AQP2 in human endometrium. The expression of AQP2 in endometrium was confirmed by RT-PCR and immunohistochemical results. The immunohistochemical analysis demonstrated that AQP2 was prominent in luminal and glandular epithelial cells of endometrium. The levels of endometrial AQP2 expression changed during the menstrual cycle and were higher in the secretory endometrium than in the proliferative endometrium. A significantly high level of AQP2 was detected at the mid-secretory phase. There was a positive correlation between the levels of the endometrial AQP2 expression and the concentrations of the serum 17beta-estradiol (E2) or/and progesterone (P4). These data for the first time corroborate that AQP2 is expressed in human endometrium and that the expression of AQP2 in human endometrium might be regulated by E2 or/and P4. The changed expression of AQP2 at different phases of the menstrual cycle may be essential to reproductive physiology in human. The high level of endometrial AQP2 expression was observed at the mid-secretory phase, the time of embryo implantation, suggesting that AQP2 might play physiological roles in the uterine receptivity.

[Research on the protocol of limited ovarian stimulation to prevent ovarian hyperstimulation syndrome].

OBJECTIVE: To investigate whether the limited ovarian stimulation (LOS) could avoid the severe ovarian hyperstimulation syndrome (OHSS) in patients with high risk of OHSS. METHODS: Ten infertile patients were diagnosed as polycystic ovarian syndrome (PCOS) with high risk of OHSS. All of them were arranged LOS cycles, a long-induction protocol using gonadotropin releasing hormone agonist (GnRHa) for controlled ovarian hyperstimulation. A full dose of human chorionic gonadotropin (10,000 U) was administered when the leading follicle reached a mean diameter of 12.0 - 14.5 mm. Oocytes were retrieved 36 hours later, followed by conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) and embryo transfer. RESULTS: Ten patients produced 11 - 35 oocytes, including 4 - 28 oocytes of metaphase II. Embryos were transferred in all of ten patients and eight clinical pregnancies were diagnosed. Unfortunately, ectopic pregnancy occurred in one of the patients. None of them experienced the symptoms of OHSS. CONCLUSIONS: LOS may play a valuable role in preventing OHSS and achieving enough mature oocytes for the patients of PCOS. Furthermore, this protocol would not reduce the pregnancy rate of the patients.

Mesoporous carbon nanoparticles capped with polyacrylic acid as drug carrier for bi-trigger continuous drug release.

A pH and redox responsive bi-trigger continuous drug release nanocarrier is developed by capping mesoporous carbon nanoparticles (MCNs) with polyacrylic acid (PAA), termed as PAA-ss-MCN. The nanocarrier contains disulfide bond units and exhibits pH responsive behavior. It provides promising potential for drug loading due to the internal uniform channels and large surface area of MCNs. PAA grafted on the exterior surface of MCNs acts as a gating layer, generating a novel nano-container and a pH-responsive intelligent nanovalve. By loading doxorubicin (DOX) in PAA-ss-MCN, its sequential release is achieved via two approaches: (1) the intracellular acidic environment induces partial release from the surface of the PAA gating layer, (2) release of the drug sealed in nanochannels via disruption of the integrity of the nanocarrier by glutathione (GSH) caused dissociation of disulfide bonds in the physiological environment. As a result, release of 62% loaded drug is readily achieved. After culturing with HeLa cells, DOX transports into the cell interior and therein exhibits pH- and GSH-sensitive release. As most tumor sites exhibit more acidic environments or high redox potential, the pH- and GSH-sensitive releasing capability of PAA-ss-MCN is particularly useful for controllable drug delivery by taking advantage of the inherent characteristics of tumor cells.

[Expression of aquaporin 2, a water channel, in human endometrium during the menstrual cycle].

OBJECTIVE: To examine the expression of aquaporin 2 (AQP2) in human endometrium. METHODS: Specimens of human endometrium were collected from 87 women at different menstrual cycles, aged 30 +/- 3, 23 cases in the proliferative phase, 30 cases in the early secretory phase and 34 cases in the mid-secretory phase respectively. Immunohistochemistry and Western blotting were utilized to detect the localization and expression of AQP2 in the endometrium. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to detect its messenger RNA. The PCR product was cloned and sequenced. RESULTS: Positive immunoreactivity of AQP2 was found in the epithelia cells and glandular epithelial cells of all specimens of human endometrium at different phases of the menstrual cycle, and all stromal cells were not stained. The reactive substance was primarily distributed in the membrane and cytoplasm, but not in the nuclei of all positive cells. In Western blotting showed dominant bands with relative molecular weight between 35,000 Da and 50,000 Da, which was corresponded to the glycosylated form of AQP2 by the positive control from rat kidney. Semi-quantitative analysis showed that the relative expression of AQP2 in the mid-secretory phase was 1.63 +/- 0.15, significantly higher than those in the early secretory phase (1.33 +/- 0.14, P < 0.05) and that in the proliferative phase (1.03 +/- 0.10, P < 0.01). Message RNA was found out in all cases by RT-PCR and the PCR product was confirmed in nearly exact (99%) consistency with the GenBank by sequencing. AQP2 mRNA was expressed in all normal endometrium at different phases, and was weakly expressed in the endometrium at the proliferative phase. Sequencing showed that the AQP2 sequence was 99% homologous with that in the GenBank. CONCLUSION: AQP2 expression in the human endometrium suggests that AQP2 may be involved in the regulation of uterine fluid homeostasis influenced by ovarian steroid hormones in the menstrual cycle.

[Expressions of peripheral lymph node addressin and GlcNAc-6-sulfotransferase in endometrium and their impacts on implantation].

OBJECTIVE: To investigate the expressions of peripheral lymph node addressin(PNAd) and GlcNAc-6-sulfotransferase (GlcNAc6ST) in endometrium and their impacts on implantation. METHODS: PNAd expression in endometrium was examined by immunohistochemistry and Western Blot from 75 women (12 from healthy women, in proliferative phase; 63 from sterile women, of whom, 27 were in early-secretory and 36 in mid-secretory phase). GlcNAc6ST mRNA was examined by real-time PCR in 41 sterile women. The 63 sterile women had underwent IVF-ET and were consequently divided into clinical pregnant (29 cases) and nonpregnant (34 cases) groups. RESULTS: (1) PNAd localized to the membrane and cytoplasm of luminal and glandular epithelia. Staining was patchy and much less intense during the proliferative phase than during the secretory phase. In Western Blot of PNAd, four bands appeared, which were Sgp200, CD34, MAdCAM-1, GlyCAM-1 respectively, and each was positively correlated with the others significantly. The former three molecular levels were significantly higher during the secretory phase as compared with the proliferative phase. Message RNA of GlcNAc6ST was positive in all cases and showed no correlation with any component of PNAd. (2)The expressions of CD34 and GlyCAM-1, but not Sgp200 and MAdCAM-1, were significantly higher in pregnant women than in nonpregnant ones. However, the GlcNAc6ST mRNA level did not differ between groups. (3) No significant difference was found in female age, methods of fertilization, thickness of endometrium on day hCG, cumulative embryo score(CES) and mean score of transferred embryo(MSTE) between the groups. CONCLUSION: PNAd expression in the human endometrium fluctuates with the menstrual cycle. Elevated CD34 and GlyCAM-1 during the secretory phase might be stimulative factors for embryo implantation. Defect in PNAd expression may account for a portion of unexplained infertility.