Amide-sialoside protein conjugates as neomucin bioshields prevent influenza virus infection.

We report the preparation of multivalent amide-sialoside-decorated human serum albumin (HSA) and bovine serum albumin (BSA) as mimics of natural mucin and bioshields against influenza virus infection. Free sialic acid with an amine on C-2 was covalently attached to the protein scaffolds using di-(N-succinimidyl) adipate. Dynamic light scattering (DLS) showed that the synthetic neomucins were able to act as bioshields and aggregate the influenza virion particles. The dissociation constants (KD) of the interactions between the prepared glycoconjugates and three different viral strains were measured by isothermal titration calorimetry (ITC) indicating the multivalent presentation of sialyl ligands on the HSA and BSA backbones can dramatically enhance the adsorbent capability compared to the corresponding monomeric sialoside. Hemagglutinin inhibition (HAI) and neuraminidase inhibition (NAI) assays showed that the glycoconjugates acted as moderate HA and NA inhibitors, thus impeding viral infection. Moreover, the different binding affinities of the glycoproteins to HA and NA proteins from different influenza viruses demonstrated the importance of HA/NA balance in viral replication and evolution. These findings provide a foundation for the development of antiviral drugs and viral adsorbent materials based on mimicking the structure of mucin.

Multivalent oleanolic acid human serum albumin conjugate as nonglycosylated neomucin for influenza virus capture and entry inhibition.

We report the synthesis of multivalent oleanolic acid (OA) protein conjugates as nonglycosylated neomucin mimic for the capture and entry inhibition of influenza viruses. Oleanolic acid derivatives bearing an amine-terminated linker were synthesized by esterification of carboxylic acid and further grafted onto the human serum albumin (HSA) via diethyl squarate method. The binding of hemagglutinin (HA) on the virion surface to the synthetic neomucin was evaluated by hemagglutination inhibition assay. The influenza virus capture ability of the PEGylated OA-HSA conjugate was further investigated by Dynamic Light Scattering (DLS), virus capture assay and Isothermal Titration Calorimeter (ITC) techniques. The pronounced agglutination of viral particles, the high capture efficiency and affinity constant indicate that this neoprotein is comparable to natural glycosylated mucin, suggesting that this material could potentially be used as anti-infective barriers to prevent virus from invading host cells. The study also rationalizes the feasibility of antiviral drug development based on OA or other antiviral small molecules conjugated protein strategies.

Multivalent S-sialoside protein conjugates block influenza hemagglutinin and neuraminidase.

A new class of S-sialoside Human Serum Albumin (HSA) and Bovine Serum Albumin (BSA) conjugates were prepared to enhance the binding affinity to hemagglutinin (HA) and neuraminidase (NA). The valency of glycoconjugates was controlled by the reaction ratio of the S-sialoside monomer and protein. Hemagglutination inhibition assay showed that these synthetic glycoproteins have higher affinity to HA than the small clusters of sialosides with lower valency, due to multivalent effect and optimized three dimensional presentation of sialosides on the protein platform. The results of fluorescent NA inhibition assay showed that some of the conjugates have moderate NA inhibitory activity, in comparison to the monomer and low valent conjugates with weak or none inhibitory activity. These synthetic sialylated proteins were not cytotoxic with concentrations up to 100 µM, since the sialylation did not change the secondary structure of protein. This new kind of conjugates can be used as lead compounds for antiviral drug design and the construction of pseudo sialoside-protein conjugates library to investigate the carbohydrate-HA/NA recognition process and a platform for the influenza virus capturing.

[Left ovarian vein thrombosis after cesarean section: a case report].

To investigate the clinical presentation, diagnosis and therapy of the postpartum ovarian vein thrombosis. Retrospective analysis was made of one case in our hospital of postpartum ovarian vein thrombosis. Literature was reviewed to investigate the clinical presentation,diagnosis and therapy of postpartum ovarian vein thrombosis. The patient presented with fever, abdominal pain, lower back pain, and ultrasound showed pyelectasis. Her blood and urine bacterial culture was negative, and the antibiotic treatment had no significant effect, which was diagnosed by CT finally. The patient's blood routine returned to normal 3 days after anti-inflammatory and anticoagulant therapy, and thrombosis was significantly reduced. She was followed-up and her condition was stable. Postpartum ovarian vein thrombosis patients often present with high temperature with unknown causes and one side abdominal pain, and CT diagnosis is needed. Timely and effective anti-inflammatory and anticoagulant therapy can significantly improve the prognosis.

[Clinical analysis of the effect of cervical conization on fertility and pregnancy outcome].

OBJECTIVE: To evaluate the effect of conization for cervical intraepithelial neoplasia on the outcome of subsequent fertility and pregnancy. METHODS: A retrospective study was performed of patients who underwent conization from 1999 to 2005 in Peking Union Medical College Hospital. The nullipara patients below 40-years old without primary or secondary infertility were followed up. RESULTS: Thirty-five patients aged from 23 to 40 years, who had pregnancy desire, were included in the study. The mean age of patients was 31 years. Twenty-five women with 26 pregnancies were identified among the 35 patients, and the pregnancy rate was 74% (26/35), which was not significantly different from that of the same patients before conization (69%, P > 0.05). Among the 26 pregnancies, there occurred one ectopic pregnancy and four cases of spontaneous abortion. In the 13 delivery cases, there were one premature delivery, two cases of premature rupture of the membrane, and ten cases of cesarean section. The sample height of the cone was less than 2.0 cm in the nine delivery cases, and the mean width of the cone was over 2.5 cm. CONCLUSION: No evidence of secondary infertility caused by cervical conization was found. There was also no significant increase in the number of either premature delivery cases or low birth weight infants. The sample height of the cone might play a more important role in the pregnancy outcome than the width, which still needs to be further verified by larger studies.

[Value of hysteroscopy and laparoscopy in differential diagnosis of gestational trophoblastic neoplasia].

OBJECTIVE: To determine the efficacy of hysteroscopy and laparoscopy in differential diagnosis of pregnancy-related diseases, including gestational trophoblastic neoplasia (GTN), incomplete abortion and ectopic pregnancy. METHODS: Twenty-seven patients with a suspected diagnosis of GTN were transferred to Peking Union Medical College Hospital from September 2003 to March 2006, and underwent hysteroscopy and laparoscopy. Clinical data of patients were reviewed retrospectively. Most patients had abnormal vaginal bleeding and persistently elevated plasma beta human chorionic gonadotropin (beta-hCG) level for a median (53 +/- 37) days (range, 15 - 125 days) after evacuation. Ultrasound revealed a lesion with affluent blood flow in intrauterine, unilateral horn of uterus, or myometrium. No positive findings were revealed by computerized tomography or X-ray of the chest in all patients. Eleven patients underwent evacuation under hysteroscope, 10 patients were diagnosed and treated by laparoscopy, and 6 by hysteroscopy and laparoscopy. RESULTS: Choriocarcinoma was diagnosed in 4 patients, who achieved complete remission by chemotherapy later. The diagnosis of GTN was ruled out in the other 23 patients, including cornual pregnancy in 12, pregnancy in rudimentary horn in 1, and incomplete abortion in 10, who were cured by hysteroscopic and laparoscopic surgery and postoperative adjuvant single dose methotrexate. CONCLUSIONS: The major causes of pregnancy-related abnormal bleeding include incomplete abortion, ectopic pregnancy, and GTN. Hysteroscopy and laparoscopy are effective alternative of diagnosis for differentiation of GTN from non-GTN and can also offer therapeutic treatment.