Comparison of the efficacy of blood and polyethylene glycol-hemoglobin in recovery of newborn piglets from hemorrhagic hypotension: effect on blood pressure, cortical oxygen, and extracellular dopamine in the brain

BACKGROUND: Successful blood substitutes, when infused in place of an equal volume of whole blood, provide similar delivery of oxygen to the tissues without introducing abnormalities in cellular metabolism. STUDY DESIGN AND METHODS: Equal volumes of whole blood (control), polyethylene glycol-hemoglobin solution at 6 g per dL, dextran solution, and physiologic saline were compared for their ability to reverse the effects of hemorrhagic hypotension on oxygenation and dopamine metabolism in the brain of newborn piglets. The decrease in mean arterial blood pressure was used as a measure of the hemorrhagic insult. Cerebral oxygen pressure was determined optically by the oxygen- dependent quenching of phosphorescence, and the extracellular level of dopamine in the corpus striatum was determined by in vivo microdialysis. RESULTS: Following a 2-hour stabilization after implantation of the microdialysis probe in the corpus striatum, the mean arterial blood pressure was decreased from 88 +/? 7 torr (control) to 42 +/? 5 torr by the removal of blood in a stepwise manner, over a period of 60 minutes. Decrease in mean arterial blood pressure caused a progressive stepwise decrease in cortical oxygen pressure from 48 +/? 5 torr to 16 +/? 4 torr at the end of bleeding. As a consequence of the decrease in oxygen pressure, extracellular dopamine increased progressively to about 2300 percent of the control value. When a volume of blood equal to that removed was returned and bicarbonate was injected to help correct arterial pH, blood pressure, cortical oxygen pressure, and extracellular dopamine all returned within the 20- to 30- minute recovery period to values not significantly different from control values. An equal volume of polyethylene glycol-hemoglobin solution, even with significantly lower hemoglobin content than whole blood, gave results comparable to those with whole blood. CONCLUSION: Polyethylene glycol-hemoglobin solution, like whole blood but in contrast to physiologic saline or dextran solution, was capable of returning the mean arterial blood pressure, cortical oxygen pressures, and extracellular dopamine nearly to control levels after acute blood loss in newborn piglets.     

Hydrodynamic Transfection for Generation of Novel Mouse Models for Liver Cancer Research

Primary liver cancers, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, are leading causes of cancer-related death worldwide. Recent large-scale genomic approaches have identified a wide number of genes whose deregulation is associated with hepatocellular carcinoma and intrahepatic cholangiocarcinoma development. Murine models are critical tools to determine the oncogenic potential of these genes. Conventionally, transgenic or knockout mouse models are used for this purpose. However, several limitations apply to the latter models. Herein, we review a novel approach for stable gene expression in mouse hepatocytes by hydrodynamic injection in combination with Sleeping Beauty–mediated somatic integration. This method represents a flexible, reliable, and cost-effective tool to generate preclinical murine models for liver cancer research. Furthermore, it can be used as an in vivo transfection method to study biochemical cross talks among multiple pathways along hepatocarcinogenesis and to test the therapeutic potential of drugs against liver cancer.CME Accreditation Statement: This activity (“ASIP 2014 AJP CME Program in Pathogenesis”) has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint sponsorship of the American Society for Clinical Pathology (ASCP) and the American Society for Investigative Pathology (ASIP). ASCP is accredited by the ACCME to provide continuing medical education for physicians.The ASCP designates this journal-based CME activity (“ASIP 2014 AJP CME Program in Pathogenesis”) for a maximum of 48 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.CME Disclosures: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.Primary liver cancer represents a major health problem worldwide. According to the World Health Organization, liver cancer represents the third leading cause of cancer-related death worldwide, accounting for approximately 695,000 deaths in 2008.¹Hepatocellular carcinoma (HCC) accounts for approximately 80% of all primary liver cancers. Epidemiological and molecular studies have demonstrated that the development of HCC spans several decades. Patients with hepatitis B (HBV) or hepatitis C (HCV) chronic infection, especially when accompanied by liver cirrhosis, are at a much higher risk of developing HCC than noninfected people.^1,2 Other risk factors for HCC include alcohol abuse, diabetes, obesity, and related metabolic syndrome. Development of HCC is a multistep process.³ Although HBV or HCV infection has been clearly linked to HCC pathogenesis, the molecular events underlying this association remain poorly understood. Because HCC often arises in the context of liver cirrhosis, it has been hypothesized that HCC development might be triggered by the repeated rounds of hepatocyte death and proliferation occurring in the cirrhotic liver. This incessant hepatocyte loss and compensatory replication might generate a permissive environment for the occurrence of genetic and/or epigenetic changes, which result in activation of oncogenes and/or loss of function of tumor-suppressor genes, eventually leading to HCC formation.^4,5 Genetic alterations observed in HCCs include mutations of p53 and β-catenin genes, activation of c-Met and insulin-like growth factor receptor tyrosine kinases, and aberrant CpG island hypermethylation of tumor-suppressor genes, such as APC, RASSF1A, and E-cadherin.^6–10 HCC is a deadly disease with limited treatment options. Indeed, tumor resection and liver transplantation can only be applied to a few patients, and sorafenib, the only drug available for the treatment of unresectable HCC, prolongs the survival of patients with HCC for only 2 to 3 months.^11,12Intrahepatic cholangiocarcinoma (ICC) accounts for approximately 10% of primary liver cancer.^13–15 In the past decades, the incidence of ICC has been increasing in the United States and the Western world.^16,17 Liver fluke infection is the major risk factor in countries, such as Thailand, where ICC is prevalent. The etiology of ICC in Western countries is less well defined, but a recent study of meta-analysis of all published ICC epidemiological data suggests that HBV or HCV infection, alcohol abuse, diabetes, and obesity are major risk factors for ICC.¹⁸ This body of evidence indicates that different primary tumor types of the liver, including HCC and ICC, might share some etiological agents. ICC is a deadly malignancy with few treatment options. In fact, to our knowledge, there is no U.S. Food and Drug Administration–approved targeted therapy for ICC. Because of its orphan status, few clinical trials for the treatment of ICC have been conducted.During the past decades, genetic studies have uncovered major signaling pathways involved in hepatocarcinogenesis. Recently, high-throughput oncogenomic studies, including microarrays, array-based comparative genomic hybridization, and deep sequencing, in combination with bioinformatics and other computational biological approaches, have identified many genes that are deregulated along HCC and ICC development. However, most of these candidate genes are likely to be passenger genes with limited implication in hepatocarcinogenesis. On the basis of these considerations, an important question arises: how can we identify the driver oncogenes and tumor-suppressor genes required for liver tumor initiation and progression? The use of liver cancer cell lines and in vitro studies has significant limitations because these cell lines are already of tumor origin. Mouse models can instead be critical to validate the oncogenic potential of a genetic event or an aberrantly altered signaling pathway. Also, because of the growing understanding of liver cancer molecular pathogenesis, mouse models represent an essential tool for in vivo screening of innovative therapeutic approaches against this deadly malignancy.     

Prolonged neutropenia resulting from antibodies to neutrophil-specific antigen NB1 following marrow transplantation

Marrow graft failure is a significant cause of morbidity following bone marrow transplantation. A case is reported of marrow graft failure due to neutrophil antibodies. A 13-year-old girl with a large granular lymphocytosis and chronic neutropenia was treated with granulocyte transfusions prior to undergoing a transplant with bone marrow from a partially matched, unrelated donor. Following the transplant, a bone marrow biopsy showed engraftment of donor myeloid cells, but the recipient remained neutropenic. Testing of the serum for neutrophil antibodies found that the recipient's serum had a high-titer neutrophil antibody. Immunoprecipitation studies using the marrow recipient's serum and 125I surface-labeled neutrophils showed that the antibody reacted to the neutrophil-specific antigen NB1. Phenotyping of neutrophils from the marrow donor found that they expressed NB1 antigen, and, in a crossmatch assay, the recipient's serum reacted with donor neutrophils. Despite treatment with granulocyte-macrophage– colony-stimulating factor, the marrow transplant recipient remained neutropenic and died of polymicrobial sepsis and aspergillosis 38 days after the transplant. The presence of high-titer antibodies to neutrophil-specific antigen NB1 in this patient following transplant likely prevented the recovery of her peripheral blood neutrophils and contributed to her death.     

Expression of neutrophil antigens after 10 days of granulocyte-colony- stimulating factor

BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) is becoming the standard agent for mobilizing granulocytes. Most granulocyte donors are given a single dose of G-CSF, but in some cases they are given G- CSF for several days, and multiple granulocyte concentrates are collected. The administration of a single dose of G-CSF induces several changes in the expression of neutrophil antigens, but the effects of multiple daily doses of G-CSF are not known. STUDY DESIGN AND METHODS: Seven healthy people received 5 microg per kg of G-CSF for 10 days. Their expression of several neutrophil antigens before, during, and after the administration of G-CSF was analyzed through the use of flow cytometry. RESULTS: The expression of L-selectin (CD62L), Fcgamma receptor (FcgammaR) III (FcgammaRIII, CD16), and the leukocyte function antigen (CD11a) decreased throughout the course of G-CSF administration, while the expression of FgammaR I (FcgammaRI, CD64) and lipopolysaccharide-binding protein receptor (CD14) increased. The expression of FcgammaR II (FcgammaRII, CD32) also increased, but not until the fourth day of G-CSF administration. The expression of amino peptidase N (CD13), C3bi receptor (CD11b), and the neutrophil beta2 integrin unit (CD18) did not change during the administration of G-CSF, but that of both CD13 and CD18 increased 3 days after the last dose. The expression of neutrophil-specific antigen NB1 initially increased, returned to pre-G-CSF levels after 4 days, and then increased again after 10 days of G-CSF administration. CONCLUSION: Changes in the expression of several neutrophil antigens occurred throughout a 10-day course of G-CSF Most of the changes occurred after one dose, but additional changes occurred later in the 10-day course and after its completion. These changes may affect the function of G-CSF-mobilized granulocytes.     

Effects of biologically modified surfaces of synthetic lenticules on corneal epithelialization in vivo

Purpose: The present study investigated the association of extracellular matrix (ECM) glycoprotein coatings with initial epithelialization of artificial lenticules in vivo. Methods: Collagen I, collagen IV, ECM and fibronectin were individually coated onto the surface of polycarbonate membranes. The membranes were then implanted in the anterior stroma of adult cats and were clinically assessed for rapidity and extent of epithelialization and the persistence of epithelial attachment. Results/Conclusions: It was demonstrated that membrane surfaces modified by collagen I, collagen IV and ECM consistently supported initial migration and attachment of corneal epithelial cells and that the surface modified with collagen I performed best.     

Elevated CNS average diffusion constant in Fabry disease

Aims : Evaluation of the average brain diffusion constant in Fabry disease. Introduction : Fabry disease is an X-linked recessive lysosomal storage disorder secondary to deficiency of α-galactosidase A and resulting in excess tissue globotriaosylceramide, particularly in cerebral blood vessels. This has been associated with cerebral hyperperfusion. Increased tissue perfusion should increase interstitial water by the Starling relationship. This hypothesis was examined by measuring the average CNS diffusion constant (D_av) in patients with Fabry disease using diffusion-weighted magnetic resonance imaging (DWI). Methods : Axial DWI was performed at b = 1000 seconds/mm² and b = 1000 seconds/mm² (TR (pulse repetition time), 10 000; TE (time to echo), 100; FOV (field of view), 22 cm; 3 mm interleaved slices; image matrix, 128 × 128; GE Signa, 1.5T). Eight healthy male volunteers (age range, 21–47 years) and 17 hemizygous patients with Fabry disease (age range, 19–49 years) were examined. Following DWI acquisition, the trace image and the diffusion distribution map were calculated. The diffusion distribution curve was then fitted by a multi-modal Gaussian curve, allowing estimation of D_av. Results : The D_av was 0.743 ±; 0.024 ±; 10^-5 cm²/second (mean ±; SD) for patients with Fabry disease and 0.726 ±; 0.014 ±; 10^-5 cm²/second for the control group. D_av was significantly increased in the patients with Fabry disease compared with the controls ( p = 0.029)
Conclusions : The elevated D_av indicates increased brain tissue water diffusivity in patients with Fabry disease, a finding consistent with increased extracellular water and increased cerebral blood flow.