Subchorionic Hemorrhage Appearing as Twin Gestation on Endovaginal Ultrasound

This case study describes a pregnant patient with vaginal bleeding who had a bedside endovaginal ultrasound in the emergency department (ED). The emergency physician identified a live intra-uterine pregnancy (IUP) with another structure that appeared to be a second gestational sac. The patient subsequently had an endovaginal ultrasound in the radiology department 46 minutes later. The attending radiologist described one live IUP and a subchorionic hemorrhage. Comparison of the ED and radiology ultrasound showed that the second structure, identified as a subchorionic hemorrhage, had significantly decreased in size. Endovaginal ultrasound in the evaluation of possible ectopic pregnancy is a useful bedside tool in the ED. We discuss a pitfall that can occur with endocavitary ultrasound when a twin gestation is presumed

The super greenhouse effect in a changing climate

In all outputs of the 1%/yr increase inCO2 climate model experiments archived under the World Climate Research Programme’s (WCRP) phase 5 of the Coupled Model Intercomparison Project (CMIP5), regions exist in the low latitudes where both the clear-sky and all-sky OLR decrease with surface warming. These are identified as regions of positive longwave feedback and are regions of a super greenhouse effect (SGE). These SGE regions are identified from feedback analysis of the 4X CO2 abrupt experiments of CMIP5, and despite their existence, there is little agreement across models as to the magnitude of the effect. The general effects of clouds on the SGE are to amplify the clear-sky SGE, but there is also poor agreement on the magnitude of the amplification that varies by an order of magnitude across models. Sensitivity analyses indicate that localized SGE regions are spatially aligned with a large moistening of the upper troposphere. The reduction in clear-sky OLR arises from a reduction in emission in the far IR with nonnegligible contributions from mid-IR emission from the midtroposphere. When viewed in the broader context of meridional heat transport, it is found that of the 1.03-PW rate of heat gained globally, 0.8 PW is absorbed in the tropics and is contributed almost equally by reductions in clear-sky longwave emission (i.e., the clear-sky SGE) and increased absorbed clear-sky solar radiation associated with increased water vapor. The processes that define the clear-sky SGE are shown to be fundamental to the way models accumulate heat and then transport it poleward

Effect of Shear Stress on Platelet Activation via the Glycoprotein VI Receptor

Cardiovascular diseases are the nation\u27s leading cause of death. Such diseases are caused by platelet response to collagen especially in the event of vascular injury leading to thrombosis. One of the platelet receptors known to bind to the collagen ligand is glycoprotein VI (GPVI) with co-receptor Fc receptor γ chain (FcRγ). By stably expressing the GPVI receptor in rat basophilic leukemia cells (RBL-2H3), which abundantly express FcRγ, but endogenously lack GPVI, studies have shown that GPVI-FcRγ is sufficient to confer adhesion as well as signaling responses to collagen as long as the receptor density is equivalent to that found on human platelets. While those investigations confirm that the GPVI receptor mediate binding to collagen under static conditions, they do not provide information on how the GPVI receptor interacts with collagen under dynamic conditions. In the present study we have used the GPVI-expressing RBL-2H3 cells to observe the kinetics of adhesion to collagen under hydrodynamic flow conditions in vitro using a parallel plate flow chamber coupled with video microscopy. We demonstrate that these cells do adhere to the surface at a low shear rate and do so at a greater adherent cell density than wild-type RBL-2H3 (WT-RBL) cells

Platelet Immunoreceptor Tyrosine-Based Activation Motif (ITAM) Signaling and Vascular Integrity

Platelets are well-known for their critical role in hemostasis, i.e. the prevention of blood loss at sites of mechanical vessel injury. Inappropriate platelet activation and adhesion, however, can lead to thrombotic complications, such as myocardial infarction and stroke. To fulfill its role in hemostasis, the platelet is equipped with various G protein-coupled receptors (GPCRs) that mediate the response to soluble agonists such as thrombin, ADP, and thromboxane A2. In addition to GPCRs, platelets express three glycoproteins (GP) that belong to the family of immunoreceptor tyrosine-based activation motif (ITAM) receptors: Fc receptor (FcR) γ chain, which is non-covalently associated with the GPVI collagen receptor, C-type lectin 2 (CLEC2), the receptor for podoplanin, and FcγRIIA, a low-affinity receptor for immune complexes. While both genetic and chemical approaches have documented a critical role for platelet GPCRs in hemostasis, the contribution of ITAM receptors to this process is less defined. Studies performed over the last decade, however, have identified new roles for platelet ITAM signaling in vascular integrity in utero and at sites of inflammation. The purpose of this review is to summarize recent findings on how platelet ITAM signaling controls vascular integrity, both in the presence and absence of mechanical injury

Reaction of Titanocene Dichloride with Acetylenedicarboxylate

The reaction of Cp2TiCl2 with either the mono- or dipotassium salt of acetylenedicarboxylic acid (ADC) gives high yields of an insoluble orange product. The insoluble compound shows potential semiconductor behavior, as evidenced by an apparent bandgap in the orange region of the visible spectrum. Under N2 ,the compound decomposes at 238° C, eventually losing approximately 46% total mass up to 1350° C. The exothermic decomposition in air, beginning at 235° C, results in the formation of titanium oxides

Requirements of SLP76 tyrosines in ITAM and integrin receptor signaling and in platelet function in vivo

Src homology 2 domain–containing leukocyte phosphoprotein of 76 kD (SLP76), an adaptor that plays a critical role in platelet activation in vitro, contains three N-terminal tyrosine residues that are essential for its function. We demonstrate that mice containing complementary tyrosine to phenylalanine mutations in Y145 (Y145F) and Y112 and Y128 (Y112/128F) differentially regulate integrin and collagen receptor signaling. We show that mutation of Y145 leads to severe impairment of glycoprotein VI (GPVI)–mediated responses while preserving outside-in integrin signaling. Platelets from Y112/128F mice, although having mild defects in GPVI signaling, exhibit defective actin reorganization after GPVI or αIIbβ3 engagement. The in vivo consequences of these signaling defects correlate with the mild protection from thrombosis seen in Y112/128F mice and the near complete protection observed in Y145F mice. Using genetic complementation, we further demonstrate that all three phosphorylatable tyrosines are required within the same SLP76 molecule to support platelet activation by GPVI