Blood Levels of Nitric Oxide, C-Reactive Protein, and Tumor Necrosis Factor-α Are Upregulated in Patients with Malignancy-Associated Hypercoagulable State: Pathophysiologic Implications

Synchronous Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma and Metastatic Squamous Cell Carcinoma of the Cervix Involving the Coronary Arteries Leading to Acute Myocardial Infarction

A 66-year-old woman presented to the hospital with a one-month history of shortness of breath, fatigue, and postmenopausal vaginal bleeding and a one-week history of chest pain. This case report discusses the rare synchronous occurrence of two different malignancies in the setting of non-ST segment elevation myocardial infarction and the relation between these unfortunate events. Besides the case presented in this report, there have been only 13 reported cases of synchronous chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) associated with metastatic squamous cell carcinoma. While it is well known that malignancy causes a hypercoagulable state, there are other mechanisms which may have contributed to the patient's myocardial ischemia including external vascular compression, tumor lysis syndrome, and anemia. This case report discusses the rarity of synchronous malignancies but the importance of understanding and consideration of cardiac events in this population.

Endothelialization of PVA/gelatin cryogels for vascular tissue engineering: effect of disturbed shear stress conditions

Mechanically, poly(vinyl alcohol) (PVA)-based cryogels are extremely well suited for vascular tissue engineering applications. However, their surface properties lead to a slow rate of endothelialization, and the mode of cell attachment leaves the endothelium susceptible to removal under physiological shear stress conditions. In this study, abrupt and ramped disturbed shear stress conditions created by a turbulent orbital flow were used to examine endothelialization on PVA/gelatin cryogels. Cell proliferation rate and apoptosis were evaluated by fluorescent activated cell sorter (FACS) analysis, and the expression of cell-adhesion molecules was used to evaluate the response of cells on cryogels to static and shear conditions by real-time polymerase chain reaction (RT-PCR). Application of a ramped shear stress had a profound effect on endothelial cell proliferation (22.30 +/- 0.20-fold increase), necrosis (eliminated), apoptosis (1.04 +/- 0.18 increase), and overall facilitation of endothelialization while concomitantly increasing nitric oxide (NO) synthesis levels. Ramped shear stress was also effective in helping the retention of the endothelial cells on the cryogel surface, whereas abrupt application caused widespread removal. Under static conditions, Selectin-P expression decreased, whereas both inter-cellular adhesion molecule (ICAM) and platelet endothelial cell adhesion molecule (PECAM)-I expression increased on cryogels over a 10-day culture period. Under both shear stress conditions, Selectin-P expression was decreased both on cryogels and tissue culture polystyrene (TCPS). Controlled application of disturbed shear stress shortens endothelialization times on cryogel surfaces, in contrast to the established antiproliferative effect of shear stress caused by laminar flow, without compromising their functionality. This demonstrates how such mechanical stimuli can be exploited to alter cellular behavior and facilitate the required outcomes for tissue engineering applications.

Direct chemiluminescence detection of nitric oxide in aqueous solutions using the natural nitric oxide target soluble guanylyl cyclase

Nitric oxide (NO) is a free radical involved in many physiological processes including regulation of blood pressure, immune response, and neurotransmission. However, the measurement of extremely low, in some cases subnanomolar, physiological concentrations of nitric oxide presents an analytical challenge. The purpose of this methods article is to introduce a new highly sensitive chemiluminescence approach to direct NO detection in aqueous solutions using a natural nitric oxide target, soluble guanylyl cyclase (sGC), which catalyzes the conversion of guanosine triphosphate to guanosine 3',5'-cyclic monophosphate and inorganic pyrophosphate. The suggested enzymatic assay uses the fact that the rate of the reaction increases by about 200 times when NO binds with sGC and, in so doing, provides a sensor for nitric oxide. Luminescence detection of the above reaction is accomplished by converting inorganic pyrophosphate into ATP with the help of ATP sulfurylase followed by light emission from the ATP-dependent luciferin-luciferase reaction. Detailed protocols for NO quantification in aqueous samples are provided. The examples of applications include measurement of NO generated by a nitric oxide donor (PAPA-NONOate), nitric oxide synthase, and NO gas dissolved in buffer. The method allows for the measurement of NO concentrations in the nanomolar range and NO generation rates as low as 100 pM/min.

Coagulation, anticoagulation and pancreatic carcinoma

An increase in coagulation in patients with pancreatic carcinoma has long been documented. In this Review, we present what is known about the pathophysiology of increased coagulation in cancer and how it applies to pancreatic carcinoma. The relationship between the activation of coagulation or symptomatic thromboembolic disease and the development of pancreatic carcinoma is explored. Data on the relationship between thromboembolic disease and the behavior of pancreatic cancer before, during or after a diagnosis is made are also reviewed. Finally, the rationale and evidence for the use of oral anticoagulants or heparin in patients with pancreatic carcinoma is presented. This Review is a critical appraisal of what is known, and when the evidence is acceptable, on the subject of thromboembolism, anticoagulation, and treatment with anticoagulants in patients with pancreatic carcinoma.

Early effects of lipopolysaccharide on cytokine release, hemodynamic and renal function in newborn piglets

BACKGROUND

Gram-negative sepsis in newborns is associated with high mortality and morbidity. Lipopolysaccharide (LPS) and cytokines released upon exposure to gram-negative sepsis are well known to be involved in the pathophysiology.

OBJECTIVE

In this report we investigate cytokine release, hemodynamic, and renal function induced by LPS in a newborn animal model with the intention to further examine early changes in gram-negative sepsis.

METHODS

Five 7- to 10-day-old domestic piglets were anesthetized and catheters placed in the jugular veins, left ventricle, and femoral artery. Urine output was monitored via suprapubic cystostomy. Mean arterial pressure, heart rate, and arterial blood gases were continuously monitored. Thirty minutes after line placement and obtaining baseline values, 0.06 mug/kg LPS were administered intravenously. One, 2, and 3 h later samples were taken to monitor tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, endothelin, and nitric oxide (NO)/nitrate via ELISA. In addition, blood flow was assessed by the microsphere method.

RESULTS

Our data show an initial surge of TNF-alpha and IL-1beta at 1 h after exposure to LPS. NO/nitrate, endothelin, and hemodynamic as well as metabolic changes became apparent mostly 3 h after exposure, by which time TNF-alpha and IL-1beta fell back to baseline.

CONCLUSIONS

Our sepsis model suggests a brief initial TNF-alpha and IL-1beta surge following LPS challenge; however, their effects become apparent by the time the levels are already subsiding. The emergence of vasoactive substances, NO and endothelin, precedes the first substantial clinical symptoms.

Thrombosis and Cancer: The Role of Screening for Occult Cancer and Recognizing the Underlying Biological Mechanisms

The association between cancer and thrombosis is well recognized. What is not known, however, is the exact relationship between these two common medical conditions. Although the development of venous thromboembolism (VTE) in a patient with known cancer is the most common presentation, in some patients, VTE may precede the diagnosis of malignancy by many months. The variation in clinical presentation is likely due to the heterogeneous biology of different tumor types and also reflects the limitations of detection or available diagnostic methods. Accumulating evidence now suggests that critical oncogenic events may also trigger activation of the coagulation cascade, leading to a prothrombotic environment that not only manifests as venous thromboembolic disease but also promotes the growth and progression of the malignancy. This chapter will review the evidence for screening for occult malignancy in patients presenting with unprovoked or idiopathic thrombosis, briefly outline the known biological relationships between malignancy and thrombosis, and summarize the clinical data on the potential anticancer effects of low molecular weight heparins (LMWHs).