In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.

In pregnancy, trophoblast invasion and uterine spiral artery remodelling are important for lowering maternal vascular resistance and increasing uteroplacental blood flow. Impaired spiral artery remodelling has been implicated in pre-eclampsia, a major complication of pregnancy, for a long time but the underlying mechanisms remain unclear. Corin (also known as atrial natriuretic peptide-converting enzyme) is a cardiac protease that activates atrial natriuretic peptide (ANP), a cardiac hormone that is important in regulating blood pressure. Unexpectedly, corin expression was detected in the pregnant uterus. Here we identify a new function of corin and ANP in promoting trophoblast invasion and spiral artery remodelling. We show that pregnant corin- or ANP-deficient mice developed high blood pressure and proteinuria, characteristics of pre-eclampsia. In these mice, trophoblast invasion and uterine spiral artery remodelling were markedly impaired. Consistent with this, the ANP potently stimulated human trophoblasts in invading Matrigels. In patients with pre-eclampsia, uterine Corin messenger RNA and protein levels were significantly lower than that in normal pregnancies. Moreover, we have identified Corin gene mutations in pre-eclamptic patients, which decreased corin activity in processing pro-ANP. These results indicate that corin and ANP are essential for physiological changes at the maternalfetal interface, suggesting that defects in corin and ANP function may contribute to pre-eclampsia.
Role of corin in trophoblast invasion and uterine spiral artery remodelling in pregnancy

Nonspecific protein-DNA interactions are inherently dynamic and involve both diffusion of the protein along the DNA and hopping of the protein from one DNA molecule or segment to another. Understanding how gene regulatory proteins interact nonspecifically with DNA in terms of both structure and dynamics is challenging because the experimental observables are an ensemble average of many rapidly exchanging states. By using a variety of NMR spectroscopic techniques, including relaxation analysis, paramagnetic relaxation enhancement, and residual dipolar couplings, we have characterized structural and kinetic aspects of the interaction of the HoxD9 homeodomain with a nonspecific, 24-bp DNA duplex in a system in which the protein is not constrained to any particular site. The data reveal that HoxD9 binds to nonspecific DNA with the same binding mode and orientation as that observed in the specific complex. The mobility, however, of Arg side-chains contacting the DNA is increased in the nonspecific complex relative to the specific one. The kinetics of intermolecular translocation between two different nonspecific DNA molecules have also been analyzed and reveal that at high DNA concentrations (such as those present in vivo) direct transfer from one nonspecific complex to another nonspecific DNA molecule occurs without going through the intermediary of free protein. This finding provides a simple mechanism for accelerating the target search in vivo for the specific site in a sea of nonspecific sites by permitting more effective sampling of available DNA sites as the protein jumps from one segment to another.
NMR structural and kinetic characterization of a homeodomain diffusing and hopping on nonspecific DNA.

OBJECTIVE To determine whether the novel avian influenza H7N9 virus can transmit from person to person and its efficiency.
DESIGN Epidemiological investigations conducted after a family cluster of two patients with avian H7N9 in March 2013.
SETTING Wuxi, Eastern China.
PARTICIPANTS Two patients, their close contacts, and relevant environments. Samples from the patients and environments were collected and tested by real time reverse transcriptase-polymerase chain reaction (rRT-PCR), viral culture, and haemagglutination inhibition assay. Any contacts who became ill had samples tested for avian H7N9 by rRT-PCR. Paired serum samples were obtained from contacts for serological testing by haemagglutination inhibition assays.
MAIN OUTCOMES MEASURES Clinical data, history of exposure before the onset of illnesses, and results of laboratory testing of pathogens and further analysis of sequences and phylogenetic tree to isolated strains.
RESULTS The index patient became ill five to six days after his last exposure to poultry. The second patient, his daughter aged 32, who provided unprotected bedside care in the hospital, had no known exposure to poultry. She developed symptoms six days after her last contact with her father. Two strains were isolated successfully from the two patients. Genome sequence and analyses of phylogenetic trees showed that both viruses were almost genetically identical. Forty three close contacts of both patients were identified. One had mild illness but had negative results for avian H7N9 by rRT-PCR. All 43 close contacts tested negative for haemagglutination inhibition antibodies specific for avian H7N9.
CONCLUSIONS The infection of the daughter probably resulted from contact with her father (the index patient) during unprotected exposure, suggesting that in this cluster the virus was able to transmit from person to person. The transmissibility was limited and non-sustainable.
Probable person to person transmission of novel avian influenza A (H7N9) virus in Eastern China, 2013: epidemiological investigation