Coagulation abnormalities in patients with metastatic colon cancer on bevacizumab therapy

14578

Background: Bevacizumab (Avastin) is a recombinant humanized monoclonal antibody to vascular endothelial growth factor (VEGF) that functions as an anti-angiogenic agent. VEGF is a glycoprotein, important for regulation of angiogenesis in normal and pathologic cells and is required for the maintenance of immature blood vessels, found in tumors. In addition to direct antiangiogenic effects, bevacizumab improves chemotherapy delivery by altering tumor vasculature as well as decreasing the size and number of liver tumors in mouse xenograft model of human colon cancer metastases. This study aimed to look for predictors of the development of major toxicities such as bleeding and clotting that would increase the incidence of such events in patients with metastatic colorectal carcinoma on Bevacizumab therapy. Methods: The study was a retrospective analysis over the past 2 years, reviewing the charts of 59 successive patients receiving bevacizumab in our institution. Particular emphasis was placed on age, gender, tumor type and location, location of metastases, chemotherapy regiment/number of cycles, past medical history, hemoglobin/hematocrit values, PT/INR values, liver function tests and albumin values at the time of the diagnosis and event. Utilizing univariant and multivariant analysis the goal was to determine contributing risk factors for increased incidence of bleeding and clotting. Results: 20.3% of the patients were found to have a major complication, such as clotting or bleeding. Once analyzed, there were four statistically significant indicators (p < 0.05) that predicted for the incidence of either one of the events. They included older patient age, low albumin values at the time of the event (as defined by the institution value of less than 3.6), location of the tumor (cecum, ascending colon and sigmoid colon were predominant), and the site of the metastasis (liver and lung). Conclusions: Clotting and bleeding complications in patients on Bevacizumab are not uncommon. It is clear that age, low albumin values, metastatic site and tumor location contribute to an increased incidence of such events in patients with metastatic colon cancer on Bevacizumab therapy.

[Table: see text]

Increased glycophorin A somatic cell variant frequency in arsenic-exposed patients of Guizhou, China

Exposure to arsenic through domestic burning arsenic-containing coal causes various tumors in a population of Guizhou, China. The glycophorin A (GPA) assay is a human mutation assay detecting somatic variation in erythrocytes expressing the MN blood type, and was used to assess genotoxicity of arsenic-exposed patients. Peripheral blood was collected from 18 adult healthy subjects and 40 arsenic-exposed patients in heparin-treated tubes. Erythrocytes were isolated, fixed in formalin and immuno-labeled with fluorescent antibodies against GPA, followed by flow cytometry analysis. Arsenic exposure increased the variant frequency (expressed as the number of variant red cells per 10(6) erythrocytes): NN, 3.7 in healthy subjects versus 21.2 in arsenic-exposed patients; N phi, 12.6 versus 33.1; MM, 13.1 versus 110; and M phi, 5.2 versus 20.3. The total GPA variant frequency was increased about five-fold (34.7 in healthy subjects versus 185 in arsenosis patients). Furthermore, the variant frequency was significantly higher in skin tumor-bearing patients: NN, 19.4 in arsenic-exposed non-tumor patients versus 31.5 in tumor-bearing patients; N phi, 29.5 versus 54.5; MM, 102 versus 159; M phi, 15.9 versus 45.1. Total GPA variant frequency in arsenic-exposed patients bearing skin tumors was significantly increased compared to patients without skin tumors (167 versus 290). The relationship between arsenic exposure history and GPA variant frequency was less evident. These data demonstrate that arsenic exposure is associated with mutations at the GPA locus, an effect exaggerated in patients bearing arsenic-induced skin tumors. The variant frequency of GPA could be a useful biomarker for arsenic exposure and arsenic carcinogenesis.

The phospholipase B homolog Plb1 is a mediator of osmotic stress response and of nutrient-dependent repression of sexual differentiation in the fission yeast Schizosaccharomyces pombe

Although phospholipase B (PLB) enzymes have been described in eukaryotes from yeasts to mammals, their biological functions are poorly understood. Here we describe the characterization of plb1, one of five genes predicted to encode PLB homologs in the fission yeast, Schizosaccharomyces pombe. The plb1 gene is dispensable under normal growth conditions but required for viability in high-osmolarity media and for normal osmotic stress-induced gene expression. Unlike mutants defective in function for the stress-activated MAP kinase Spc1, plb1Delta cells are not hypersensitive to oxidative or temperature stresses, nor do they undergo a G2-specific arrest in response to osmotic stress. In addition to defects in osmotic stress response, plb1Delta cells exhibit a cold-sensitive defect in nutrient-mediated mating repression, a phenotype reminiscent of mutants in the cyclic AMP (cAMP) pathway. We show that, like plb1Delta cells, mutants in the cAMP pathway are defective for growth in high-osmolarity media, demonstrating a previously unrecognized role for the cAMP pathway in osmotic stress response. Furthermore, we show that gain-of function in the cAMP pathway can rescue the osmosensitive growth defect of plb1Delta cells, suggesting that the cAMP pathway is a potential downstream target of the actions of Plb1 in S. pombe.

Adaptation of cardiac morphology and function to endurance and strength training. A comparative study using MR imaging and echocardiography in males and females

Left ventricular (LV) dimensions and function and maximal oxygen uptake (VO(2)max) were measured in endurance-trained (10 male, m, 10 female, f), strength-trained athletes (8 m, 10 f) and untrained subjects (9 m, 10 f). LV dimensions were measured using magnetic resonance imaging (MRI) and echocardiography and the results were equal irrespective of method. Endurance-trained m and f had significantly higher LV volumes and mass than both strength-trained and controls. No VO(2)max or dimensional differences were seen between strength-trained and untrained subjects. In endurance-trained males, LV volumes and mass/kg bw were higher than in endurance-trained females. There was no significant gender difference for strength-trained or untrained subjects regarding body weight-related heart dimensions. It is concluded that LV dimensions and volumes are strongly dependent on oxygen transport capacity in normal subjects practising different modes of training, and that the gender differences, if LV dimensions are related to aerobic work capacity, are smaller than previously reported.

Enzyme therapy for lysosomal acid lipase deficiency in the mouse

Lysosomal acid lipase (LAL) is the critical enzyme for the hydrolysis of the triglycerides (TG) and cholesteryl esters (CE) delivered to lysosomes. Its deficiency produces two human phenotypes, Wolman disease (WD) and cholesteryl ester storage disease (CESD). A targeted disruption of the LAL locus produced a null (lal( -/-)) mouse model that mimics human WD/CESD. The potential for enzyme therapy was tested using mannose terminated human LAL expressed in Pichia pastoris (phLAL), purified, and administered by tail vein injections to lal( -/-) mice. Mannose receptor (MR)-dependent uptake and lysosomal targeting of phLAL were evidenced ex vivo using competitive assays with MR-positive J774E cells, a murine monocyte/macrophage line, immunofluorescence and western blots. Following (bolus) IV injection, phLAL was detected in Kupffer cells, lung macrophages and intestinal macrophages in lal( -/-) mice. Two-month-old lal( -/-) mice received phLAL (1.5 U/dose) or saline injections once every 3 days for 30 days (10 doses). The treated lal( -/-) mice showed nearly complete resolution of hepatic yellow coloration; hepatic weight decreased by approximately 36% compared to PBS-treated lal( -/-) mice. Histologic analyses of numerous tissues from phLAL-treated mice showed reductions in macrophage lipid storage. TG and cholesterol levels decreased by approximately 50% in liver, 69% in spleen and 50% in small intestine. These studies provide feasibility for LAL enzyme therapy in human WD and CESD.

Synthesis and Diels-Alder reactions of 4-vinylimidazoles

[structure in text] The synthesis of several 4-vinylimidazoles via Stille cross-coupling reactions of the corresponding protected 4-iodoimidazoles with tributylvinylstannane is described. These heterocyclic dienes are shown to be effective partners in the Diels-Alder reaction, providing adducts in good yield and exhibiting useful levels of isomer selectivity and stereoselectivity (endo/exo).

[Clinical study: the effects of inhaling nitrous oxide for analgesia labor on pregnant women and fetus]

OBJECTIVE

To investigate the effect of the inhalation of nitrous oxide premixed with oxygen (50%:50%) for analgesia labor on maternal and fetus.

METHODS

A total of 100 cases of pregnant women were provided with nitrous oxide premixed with oxygen (50%:50%) (control group); Another 100 cases were provided only with oxygen (comparison group). Recording duration of the Labor, way of delivery, bleeding volume, Apgars score, blood gas analysis to maternal radius artery and fetal umbilical blood among all patients.

RESULTS

The effect for analgesia labor of the premixed gas was much better than that of control group, but there were no significant differences in time of labor, bleeding volume, Apgars score between the two groups.

CONCLUSIONS

The inhalation of nitrous oxide premixed with oxygen (50%:50%) for analgesia labor benefits pregnant women because of keeping them being a good mental and physical condition. The inhalation of nitrous oxide for analgesia labor is a safe, effective and easy method.