61 research outputs found
Atrial and placental melanoma metastasis: a case report and literature review
Malignant melanoma can metastasize to virtually any organ of the body. The aggressiveness is determined by the primary site, depth of dermal invasion, presence or absence of ulceration, lymphovascular infiltration and regional lymph node involvement. We report a case of a pregnant woman with a previous history of stage 3 melanoma who presented with cardiac metastasis and placental melanoma infiltration. A review of literature on cardiac and placental involvement of melanoma is also provided
Surface-Enhanced Nitrate Photolysis on Ice
Heterogeneous nitrates photolysis is the trigger for many chemical processes occurring in the polar boundary layer and is widely believed to occur in a quasi-liquid layer (QLL) at the surface of ice. The dipole forbidden character of the electronic transition relevant to boundary layer atmospheric chemistry and the small photolysis/photoproducts quantum yields in ice (and in water) may confer a significant enhancement and interfacial specificity to this important photochemical reaction at the surface of ice. Using amorphous solid water films at cryogenic temperatures as models for the disordered interstitial air/ice interface within the snowpack suppresses the diffusive uptake kinetics thereby prolonging the residence time of nitrate anions at the surface of ice. This approach allows their slow heterogeneous photolysis kinetics to be studied providing the first direct evidence that nitrates adsorbed onto the first molecular layer at the surface of ice are photolyzed more effectively than those dissolved within the bulk. Vibrational spectroscopy allows the ~3-fold enhancement in photolysis rates to be correlated with the nitrates’ distorted intramolecular geometry thereby hinting at the role played by the greater chemical heterogeneity in their solvation environment at the surface of ice than in the bulk. A simple 1D kinetic model suggests 1-that a 3(6)-fold enhancement in photolysis rate for nitrates adsorbed onto the ice surface could increase the photochemical NO[subscript 2] emissions from a 5(8) nm thick photochemically active interfacial layer by 30%(60)%, and 2-that 25%(40%) of the NO[subscript 2] photochemical emissions to the snowpack interstitial air are released from the top-most molecularly thin surface layer on ice. These findings may provide a new paradigm for heterogeneous (photo)chemistry at temperatures below those required for a QLL to form at the ice surface
IL-1α Mediated Chorioamnionitis Induces Depletion of FoxP3+ Cells and Ileal Inflammation in the Ovine Fetal Gut
Endotoxin induced chorioamnionitis increases IL-1 and provokes an inflammatory response in the fetal ileum that interferes with intestinal maturation. In the present study, we tested in an ovine chorioamnionitis model whether IL-1 is a major cytokine driving the inflammatory response in the fetal ileum.Sheep bearing singleton fetuses received a single intraamniotic injection of recombinant ovine IL-1α at 7, 3 or 1 d before caesarian delivery at 125 days gestational age (term = 150 days).3 and 7 d after IL-1α administration, intestinal mRNA levels for IL-4, IL-10, IFN-γ and TNF-α were strongly elevated. Numbers of CD3+ and CD4+ T-lymphocytes and myeloidperoxidase+ cells were increased whereas FoxP3+ T-cells were detected at low frequency. This increased proinflammatory state was associated with ileal mucosal barrier loss as demonstrated by decreased levels of the intestinal fatty acid binding protein and disruption of the tight junctional protein ZO-1.Intraamniotic IL-1α causes an acute detrimental inflammatory response in the ileum, suggesting that induction of IL-1 is a critical element in the pathophysiological effects of endotoxin induced chorioamnionitis. A disturbed balance between T-effector and FoxP3+ cells may contribute to this process
Formation of reactive nitrogen oxides from urban grime photochemistry
Impervious surfaces are ubiquitous in urban environments and
constitute a substrate onto which atmospheric constituents can deposit and
undergo photochemical and oxidative processing, giving rise to “urban
grime” films. HNO<sub>3</sub> and N<sub>2</sub>O<sub>5</sub> are important sinks for NO<sub><i>x</i></sub>
in the lower atmosphere and may be deposited onto these films, forming
nitrate through surface hydrolysis. Although such deposition has been
considered as a net loss of NO<sub><i>x</i></sub> from the atmosphere, there is
increasing evidence that surface-associated nitrate undergoes further
reaction. Here, we examine the gas phase products of the photochemistry of
real, field-collected urban grime using incoherent broadband cavity-enhanced
absorption spectroscopy (IBBCEAS). Gas phase nitrogen oxides are emitted
upon illumination of grime samples and their production increases with
ambient relative humidity (RH) up to 35 % after which the production
becomes independent of RH. These results are discussed in the context of
water uptake onto and evaporation from grime films
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Tumor Suppressor Gene, Cell Surface Adhesion Molecule, and Multidrug Resistance in MĂĽllerian Serous Carcinomas: Clinical Divergence without Immunophenotypic Differences
Objectives. We hypothesize that differences in the expression of selected tumor suppressor genes, cell surface adhesion molecules, and multidrug resistance glycoproteins could account for some of the reported differences between uterine serous carcinoma (USC) and extrauterine serous carcinomas (ESC), including ovarian and primary peritoneal carcinoma (OSC and PSC, respectively).
Methods. We studied the expression of the following antigens in 20 USCs, 20 OSCs, and 10 PSCs: p53 and mdm-2 (tumor suppressor genes), CD44 and CD44v6 (cell surface adhesion molecules), and the p-glycoprotein (a multidrug resistance protein recognized by two antibodies, C494 and JSB1). We further studied chemotherapeutic drug resistance by examining reports prepared using the Oncotech Extreme Drug Resistance Assay from 24 of the 50 study patients. Clinical data were obtained from medical record review.
Results. USC, OSC, and PSC patients were similar with respect to mean age at diagnosis, mean gravidity, mean parity, personal history of breast cancer, percentage treated with chemotherapy, and survival at 3 and 5 years postdiagnosis. Significant clinical differences included a high prevalence of nulliparity in OSC (P = 0.05), a low prevalence of Caucasian race in USC (P = 0.008), a paucity of stage I patients in OSC and PSC (P = 0.03), a high prevalence of familial breast cancer in OSC (P = 0.06), and superior 2-year survival in OSC (P = 0.02). Seventy-five percent of USCs, 52% of OSCs, and 60% of PSCs expressed p53. Five percent of USCs, 19% of OSCs, and 0% of PSCs expressed mdm-2. Forty percent of USCs, 33% of OSCs, and 10% of PSCs expressed CD44. None of the USCs, OSCs, or PSCs expressed CD44v6. Sixty-one percent of USCs and OSCs and 82% of PSCs expressed C494 while 17% of USCs, 19% of OSCs, and 20% of PSCs expressed JSB1. None of these apparent differences was statistically significant. USC, OSC, and PSCs patients did not demonstrate significant differences with respect to extreme drug resistance. However, the following trends were noted (P = 0.06): more prevalent low drug resistance for cyclophosphamide in OSC compared with USC and more prevalent extreme drug resistance for etoposide in OSC compared with USC.
Conclusions. Therefore, despite significant clincial differences, the USCs and ESCs in our series do not differ significantly with respect to the expression of the tumor suppressor genes, cell surface adhesion molecules, and drug resistance proteins studied. It is premature, however, to recommend that USCs and ESCs should be treated identically
Organic Composition, Chemistry, and Photochemistry of Urban Film in Leipzig, Germany
In polluted urban environments, windows
and building surfaces are
coated with a complex film of chemicals. Despite its high surface-to-volume
ratio and direct exposure to sunlight, few studies have directly investigated
the role that this “urban film” may play in promoting
the chemistry and photochemistry of semivolatile organic species contained
within it. Here, we report results from a field investigation of the
organic composition of urban film and particulate matter (PM<sub>10</sub>) samples collected at an urban site in Leipzig, Germany, in which
we provide clear evidence for the influence of anthropogenic processes
on film composition. In this study, we find that the ratio of water-soluble
organic carbon (WSOC) to the total ionic content of film samples decreases
with atmospheric exposure time, which suggests that urban film growth
proceeds first via the condensation of semivolatile species, and that
the coating thus formed enhances the dry deposition of particles.
Further, we find that the polycyclic aromatic hydrocarbon (PAH) abundance
profiles in light-exposed films are different from those in films
collected under light-shielded conditions, which represents the first
direct evidence that urban films serve as a photochemical sink for
semivolatile organic pollutants. Finally, we find that the PAH and <i>n</i>-alkane profiles of urban film samples differ substantially
from colocated PM<sub>10</sub> samples, which we suggest reflects
both the contribution of settled coarse particulate matter to the
overall film composition and the influence of in-film oxidative processes.
Together, these results highlight the unique reactive environment
afforded by urban film and underscore the need for further studies
of urban surface chemistry
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