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The pathophysiology of isolated pleural effusion in ovarian hyperstimulation syndrome (OHSS) is not well defined. The objective of the current review is to delineate the pathophysiology, risk factors, preventive measures, and therapeutic options of isolated pleural effusion in severe OHSS. Major databases were searched until June 2016. Studies evaluating women who presented with pleural effusion as the sole extra-ovarian manifestation of severe OHSS were included. Data were extracted from 24 articles encompassing 30 reported cases. Values were expressed as mean ± SEM. Patients were young (31.5 ± 0.8 years old) and 29.1% of them were diagnosed with polycystic ovary syndrome. All the patients received human chorionic gonadotropin to trigger oocyte maturation. Estradiol level was 3110 ± 330 pg/mL on the day of the ovulatory trigger. Dyspnea was the presenting symptom in 86.6% of the patients. Pleural effusion was predominantly on the right side (80%). Ninety percent of the patients underwent thoracentesis (4332 ± 769 mL): 66.7% exudate and 33.3% transudate. Fluid initially accumulates in the peritoneal cavity then enters the pleural space due to the pressure gradient through the thoracic duct and diaphragmatic defects, which are more common on the right side. The risk factors, prevention, and management, which are also discussed in this review, are similar to those of severe OHSS. [ABSTRACT FROM AUTHOR]

Human cleavage-stage embryos frequently acquire chromosomal aneuploidies during mitosis due to unknown mechanisms. Here, we show that S phase at the 1-cell stage shows replication fork stalling, low fork speed, and DNA synthesis extending into G2 phase. DNA damage foci consistent with collapsed replication forks, DSBs, and incomplete replication form in G2 in an ATR- and MRE11-dependent manner, followed by spontaneous chromosome breakage and segmental aneuploidies. Entry into mitosis with incomplete replication results in chromosome breakage, whole and segmental chromosome errors, micronucleation, chromosome fragmentation, and poor embryo quality. Sites of spontaneous chromosome breakage are concordant with sites of DNA synthesis in G2 phase, locating to gene-poor regions with long neural genes, which are transcriptionally silent at this stage of development. Thus, DNA replication stress in mammalian preimplantation embryos predisposes gene-poor regions to fragility, and in particular in the human embryo, to the formation of aneuploidies, impairing developmental potential. [Display omitted] • 1-cell embryos show replication fork stalling, with replication extending into G2 phase • Incompletely replicated DNA is converted to chromosome breaks and aneuploidy in mitosis • Spontaneous chromosome breaks and G2 DNA synthesis occur in congruent gene-poor regions • Chromosome fragility in human embryos occurs independently of embryonic genome activation In human preimplantation embryos, DNA replication in G2 phase results in chromosome breakage, segmental aneuploidies, and poor embryo quality. [ABSTRACT FROM AUTHOR]

This Letter describes how gold pyramidal nanoshells (nanopyramids) can be assembled into low- and high-order structures by varying the rate of solvent evaporation and surface wettability. Single-particle and individual-cluster dark field scattering spectra on isolated, dimers and trimers of nanopyramids were compared. We found that the short wavelength resonances blue-shifted as the particles assembled; the magnitude of this shift was greater for high-order structures. To test which assembled architecture supported a larger Raman-active volume, we compared their surface enhanced Raman scattering (SERS) response of the resonant Raman molecule methylene blue (λ(ex) = 633 nm). We discovered that high-order structures exhibited more Raman scattering compared to low-order assemblies. Finite-difference time-domain modeling of nanopyramid assemblies revealed that the highest electromagnetic field intensities were localized between adjacent particle faces, a result that was consistent with the SERS observations. Thus, the local spatial arrangement of the same number of nanoparticles in assembled clusters is an important design parameter for optimizing nanoparticle-based SERS sensors.