Group C strep mediastinitis.

This case is significant to the practice of emergency medicine because it represents the development of an uncommon and potentially fatal mediastinal infection from a commonly encountered and appropriately treated community respiratory pathogen. Most published reports on mediastinitis are those that are status-post cardiothoracic surgery. In our report, we discuss a case of a healthy, young individual who developed this morbid entity from extension of a simple respiratory infection where Group C Streptococcus has been isolated as the causative organism, which to our knowledge has not been previously reported. Further, this report outlines how a community acquired pneumonia progressed to a life threatening illness despite proper initial treatment per local and national guidelines.

CAVH in the Combat Environment: A Case Report and Lessons Learned in Southern Afghanistan.

Background: Acute kidney injury is a common complication of both civilian and military trauma. The lack of dedicated resources restrict dialysis in the forward setting. We report a case of a combat polytrauma and renal failure, using continuous arteriovenous hemofiltration to clear uremia and remove volume, allowing for ventilator liberation and safe disposition. Materials and Methods: The patient presented with traumatic lower extremity injuries and abdominal wounds and developed acute post-traumatic renal failure. Using available supplies, the patient was cannulated for continuous arteriovenous hemofiltration. Aggressive fluid and electrolyte management accomplished specific goals of ventilator liberation and clearance of uremia. Results: Over 48 h, blood urea nitrogen was reduced from 101 mg/dL to 63 mg/dL. Creatinine was reduced from 8.2 mg/dL to 4.7 mg/dL. Acute respiratory distress syndrome was improved reducing P:F (PaO2:FiO2) ratio from 142 to 210. The patient was extubated and transferred safely. Conclusions: The ability to perform acute dialysis can be lifesaving. Although resource constrained, we created a dialysis system in the forward environment with a filter and universally available equipment. This represents the first described use of continuous arteriovenous hemofiltration at the NATO Role 3 hospital in Afghanistan. This technique represents another potential tool for deployed trauma teams to improve care.

Management of an intrapleural foreign body and empyema with video-assisted thoracoscopy.

Intrapleural foreign bodies are rare and there are few reports on the occurrence and management of this uncommon clinical presentation. We report a case of a patient with a history of ingesting multiple foreign bodies, which resulted in multiple laparotomy procedures for extraction. The patient recently required surgical removal of innumerable ingested foreign bodies from the stomach and developed a left empyema post-operatively. Subsequent imaging studies revealed evidence of a foreign object in the left pleural space without evidence of an esophageal perforation or diaphragm injury.

Timescales of methane seepage on the Norwegian margin following collapse of the Scandinavian Ice Sheet.

Gas hydrates stored on continental shelves are susceptible to dissociation triggered by environmental changes. Knowledge of the timescales of gas hydrate dissociation and subsequent methane release are critical in understanding the impact of marine gas hydrates on the ocean-atmosphere system. Here we report a methane efflux chronology from five sites, at depths of 220-400 m, in the southwest Barents and Norwegian seas where grounded ice sheets led to thickening of the gas hydrate stability zone during the last glaciation. The onset of methane release was coincident with deglaciation-induced pressure release and thinning of the hydrate stability zone. Methane efflux continued for 7-10 kyr, tracking hydrate stability changes controlled by relative sea-level rise, bottom water warming and fluid pathway evolution in response to changing stress fields. The protracted nature of seafloor methane emissions probably attenuated the impact of hydrate dissociation on the climate system.

North Atlantic forcing of moisture delivery to Europe throughout the Holocene.

Century-to-millennial scale fluctuations in precipitation and temperature are an established feature of European Holocene climates. Changes in moisture delivery are driven by complex interactions between ocean moisture sources and atmospheric circulation modes, making it difficult to resolve the drivers behind millennial scale variability in European precipitation. Here, we present two overlapping decadal resolution speleothem oxygen isotope (δ(18)O) records from a cave on the Atlantic coastline of northern Iberia, covering the period 12.1-0 ka. Speleothem δ(18)O reveals nine quasi-cyclical events of relatively wet-to-dry climatic conditions during the Holocene. Dynamic Harmonic Regression modelling indicates that changes in precipitation occurred with a ~1500 year frequency during the late Holocene and at a shorter length during the early Holocene. The timing of these cycles coincides with changes in North Atlantic Ocean conditions, indicating a connectivity between ocean conditions and Holocene moisture delivery. Early Holocene climate is potentially dominated by freshwater outburst events, whilst ~1500 year cycles in the late Holocene are more likely driven by changes internal to the ocean system. This is the first continental record of its type that clearly demonstrates millennial scale connectivity between the pulse of the ocean and precipitation over Europe through the entirety of the Holocene.

MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics.

Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (re). In situ COT, LWP, and re were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and re 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14-36%. MODIS in situ re correlations were strong, but MODIS 2.1 µm re exceeded in situ re, which contributed to LWP bias; in POST, MODIS re was 20-30% greater than in situ re. Maximum in situ re near cloud top showed comparisons nearer 1:1. Other MODIS re bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS re bias that propagates to LWP while still capturing variability.

238U/235U Systematics in terrestrial uranium-bearing minerals.

The present-day (238)U/(235)U ratio has fundamental implications for uranium-lead geochronology and cosmochronology. A value of 137.88 has previously been considered invariant and has been used without uncertainty to calculate terrestrial mineral ages. We report high-precision (238)U/(235)U measurements for a suite of uranium-bearing minerals from 58 samples representing a diverse range of lithologies. This data set exhibits a range in (238)U/(235)U values of >5 per mil, with no clear relation to any petrogenetic, secular, or regional trends. Variation between comagmatic minerals suggests that (238)U/(235)U fractionation processes operate at magmatic temperatures. A mean (238)U/(235)U value of 137.818 ± 0.045 (2σ) in zircon samples reflects the average uranium isotopic composition and variability of terrestrial zircon. This distribution is broadly representative of the average crustal and "bulk Earth" (238)U/(235)U composition.

Ethanol-TGFalpha-MEK signaling promotes growth of human hepatocellular carcinoma.

BACKGROUND: Chronic ethanol intake is a significant risk factor for the development of cirrhosis and hepatocellular carcinoma (HCC). The effects of ethanol on extracellular signal-regulated kinase (ERK) activation, transforming growth factor alpha (TGF-alpha), and HCC growth were examined in this study. METHODS: HepG2, SKHep, Hep3B human HCC cells, or normal human hepatocytes were treated with ethanol (0-100 mM), exogenous TGF-alpha, TGF-alpha neutralization antibody or the MEK inhibitor U0126. TGF-alpha levels were quantified by ELISA. Growth was determined by trypan blue-excluded cell counts. Cell cycle phase distribution was determined by flow cytometry. Protein expression was determined by Western blot. RESULTS: Ethanol treatment (10-40 mM) increased ERK activation in HepG2 and SKHep HCC cells but not in Hep3B or human hepatocyte cells. Growth increased in HepG2 (174 +/- 29%, P < 0.05) and SKHep (149 +/- 12%, P < 0.05) cells in response to ethanol treatment. Correspondingly, ethanol increased S phase distribution in these cells. U0126 suppressed ethanol-induced growth increases. Ethanol treatment for 24 h also raised TGF-alpha levels in HepG2 cells (118%-198%) and SKHep cells (112%-177%). Exogenous administration of recombinant TGF-alpha mimicked the ethanol-induced growth in HepG2 and SKHep cells; TGF-alpha neutralization antibody effectively abrogated this effect. The TGF-a neutralization antibody also prevented ERK activation by ethanol in HepG2 cells. CONCLUSIONS: These data demonstrate that clinically relevant doses of ethanol stimulate ERK-dependent proliferation of HCC cells. Ethanol up-regulates TGF-alpha levels in HCC cells and enhances growth through cell cycles changes, which appear to be mediated through TGF-alpha-MEK-ERK signaling. Ethanol-MEK signaling in normal hepatocytes is absent, suggesting that ethanol promotion of HCC growth may in part depend upon the acquisition of cancer-specific signaling by hepatocytes.

Evolving Pb isotope signatures of London airborne particulate matter (PM 10)-constraints from on-filter and solution-mode MC-ICP-MS.

Pb isotope compositions of biologically significant PM(10) atmospheric particulates from a busy roadside location in London UK were measured using solution- and laser ablation-mode MC-ICP-MS. The solution-mode data for PM(10) sampled between 1998-2001 document a dramatic shift to increasingly radiogenic compositions as leaded petrol was phased out. LA-MC-ICP-MS isotope analysis, piloted on a subset of the available samples, is shown to be a potential reconnaissance analytical technique. PM(10) particles trapped on quartz filters were liberated from the filter surface, without ablating the filter substrate, using a 266 nm UV laser and a dynamic, large diameter, low-fluence ablation protocol. The Pb isotope evolution noted in the London data set obtained by both analytical protocols is similar to that observed elsewhere in Western Europe following leaded petrol elimination. The data therefore provide important baseline isotope composition information useful for continued UK atmospheric monitoring through the early 21(st) century.

Suppression of pancreatic tumor growth by combination chemotherapy with sulindac and LC-1 is associated with cyclin D1 inhibition in vivo.

The design of novel targeted or combination therapies may improve treatment options for pancreatic cancer. Two targets of recent interest are nuclear factor-kappaB (NF-kappaB) and cyclooxygenase (COX), known to be activated or overexpressed, respectively, in pancreatic cancer. We have previously shown that parthenolide, a proapoptotic drug associated with NF-kappaB inhibition, enhanced the growth suppression of pancreatic cancer cells by the COX inhibitor sulindac in vitro. In the present study, a bioavailable analogue of parthenolide, LC-1, and sulindac were evaluated in vivo using a xenograft model of human pancreatic cancer. Treatment groups included placebo, low-dose/high-dose LC-1 (20 and 40 mg/kg), low-dose/high-dose sulindac (20 and 60 mg/kg), and low-dose combination LC-1/sulindac (20 mg/kg each). In MiaPaCa-2 xenografts, tumor growth was inhibited by either high-dose sulindac or LC-1. In BxPC-3 xenografts, tumor size was significantly reduced by treatment with the low-dose LC-1/sulindac combination or high-dose sulindac alone (P < 0.05). Immunohistochemistry of BxPC-3 tumors revealed a significant decrease in Ki-67 and CD31 staining by high-dose sulindac, with no significant changes in COX-1/COX-2 levels or activity in any of the treatment groups. NF-kappaB DNA-binding activity was significantly decreased by high-dose LC-1. Cyclin D1 protein levels were reduced by the low-dose LC-1/sulindac combination or high-dose sulindac alone, correlating with BxPC-3 tumor suppression. These results suggest that LC-1 and sulindac may mediate their antitumor effects, in part, by altering cyclin D1 levels. Furthermore, this study provides preclinical evidence for the therapeutic efficacy of these agents.