Identification of swallowing disorders in early and mid-stage Parkinson's disease using pattern recognition of pharyngeal high-resolution manometry data.

BACKGROUND: Parkinson's disease (PD) can cause severe dysphagia, especially later in disease progression. Early identification of swallowing dysfunction may lead to earlier intervention. Pharyngeal high-resolution manometry (HRM) provides complementary information to videofluoroscopy, with advantages of being quantitative and objective. Artificial neural network (ANN) classification can examine non-linear relationships among multiple variables with relatively low bias. We evaluated if ANN techniques could differentiate between patients with PD and healthy controls. METHODS: Simultaneous videofluoroscopy and pharyngeal HRM were performed on 31 patients with early to mid-stage PD and 31 age- and sex-matched controls during thin-liquid swallows of 2 cc, 10 cc and comfortable sip volume. We performed multilayer-perceptron analyses on only videofluoroscopic data, only HRM data or a combination of the two. We also evaluated variability-based parameters, representing variability in manometric parameters across multiple swallows. We hypothesized that patients with PD and controls would be classified with at least 80% accuracy, and that combined videofluoroscopic and HRM data would classify participants better than either alone. KEY RESULTS: Classification rates were highest with all parameters considered. Maximum classification rate was 82.3 ± 5.2%, recorded for 2 cc swallows. Inclusion of variability-based parameters improved classification rates. Classification rates using only manometric parameters were similar to those using all parameters, and rates were substantially lower for the comfortable sip volumes. CONCLUSIONS & INFERENCES: Results from these classifications highlight the differences between swallowing function in patients with early and mid-stage PD and healthy controls. Early identification of swallowing dysfunction is key to developing preventative swallowing treatments for those with PD.

Using antifibrinolytics in the peripartum period - concern for a hypercoagulable effect?

INTRODUCTION: Although antifibrinolytic agents are used to prevent and treat hemorrhage, there are concerns about a potential increased risk for peripartum venous thromboembolism. We sought to determine the impact of tranexamic acid and ɛ-aminocaproic acid on in vitro clotting properties in pregnancy. METHODS: Blood samples were obtained from healthy pregnant, obese, and preeclamptic pregnant women (n = 10 in each group) prior to delivery as well as from healthy non-pregnant controls (n = 10). Maximum clot firmness (MCF) and clotting time (CT) were measured using rotation thromboelastometry in the presence of tranexamic acid (3, 30, or 300 µg/mL) or ɛ-aminocaproic acid (30, 300, or 3000 µg/mL). ANOVA and regression analyses were performed. RESULTS: Mean whole blood MCF was significantly higher in healthy pregnant vs. non-pregnant women (66.5 vs. 57.5 mm, p < 0.001). Among healthy pregnant women, there was no significant difference between mean MCF (whole blood alone, and with increasing tranexamic acid doses = 66.5, 66.1, 66.4, 66.3 mm, respectively; p = 0.25) or mean CT (409, 412, 420, 424 sec; p = 0.30) after addition of tranexamic acid. Similar results were found using ɛ-aminocaproic acid. Preeclamptic women had a higher mean MCF after the addition of ɛ-aminocaproic acid and tranexamic acid (p = 0.05 and p = 0.04, respectively) compared to whole blood alone. CONCLUSIONS: Pregnancy is a hypercoagulable state, as reflected by an increased MCF compared to non-pregnant women. Addition of antifibrinolytic therapy in vitro does not appear to increase MCF or CT for non-pregnant, pregnant, and obese women. Whether antifibrinolytics are safe in preeclampsia may require further study.

Preliminary study of indirect CT lymphography-guided sentinel lymph node biopsy in a tongue VX2 carcinoma model.

The feasibility of using indirect CT lymphography (CT-LG) to guide sentinel lymph node (SLN) biopsy in a rabbit model of tongue VX2 carcinoma with cervical lymph node metastasis was studied. Tongue VX2 carcinoma with cervical lymph node metastasis was induced in 19 rabbits by injecting VX2 carcinoma suspension into the tongue submucosa. SLN biopsy was performed under the guidance of indirect CT-LG. SLN identification was performed by indirect CT-LG combined with blue dye injection in 2 rabbits. Tongue SLNs were identified preoperatively by indirect CT-LG and blue-stained SLNs were visualized intraoperatively. Only one SLN was enhanced in each side of the neck, lateral to the larynx-tracheal region. CT attenuation values of the enhanced SLNs were 782.4+/-46.6, 443.1+/-68.5, 180.3+/-20.6 and 80.5+/-10.7 HU at 1, 5, 15 and 20 min after contrast injection. Overall, ipsilateral SLN identification rate was 97.4% and contralateral SLN identification rate was 100%. Ipsilateral SLN metastasis was verified in all rabbits (100%), bilateral SLN metastasis occurred in 8 rabbits (42%), and micrometastasis was found in 3 rabbits (16%). Indirect CT-LG may be useful for guiding SLN biopsies in tongue cancer. Combining indirect CT-LG with blue dye injection may improve preoperative and intraoperative SLN identification.

Platelet functions beyond hemostasis.

Although their central role is in the prevention of bleeding, platelets probably contribute to diverse processes that extend beyond hemostasis and thrombosis. For example, platelets can recruit leukocytes and progenitor cells to sites of vascular injury and inflammation; they release proinflammatory and anti-inflammatory and angiogenic factors and microparticles into the circulation; and they spur thrombin generation. Data from animal models suggest that these functions may contribute to atherosclerosis, sepsis, hepatitis, vascular restenosis, acute lung injury, and transplant rejection. This article represents an integrated summary of presentations given at the Fourth Annual Platelet Colloquium in January 2009. The process of and factors mediating platelet-platelet and platelet-leukocyte interactions in inflammatory and immune responses are discussed, with the roles of P-selectin, chemokines and Src family kinases being highlighted. Also discussed are specific disorders characterized by local or systemic platelet activation, including coronary artery restenosis after percutaneous intervention, alloantibody-mediated transplant rejection, wound healing, and heparin-induced thrombocytopenia.

Hypercoagulation and thrombophilia in liver disease.

A complex balance exists between endogenous procoagulants and the anticoagulant system in liver disease patients. Hypercoagulable events occur in cirrhosis patients despite the well-known bleeding diathesis of liver disease. These events may be clinically evident, such as in portal vein thrombosis or pulmonary embolism, but these conditions may also be a silent contributor to certain disease states, such as portopulmonary hypertension or parenchymal extinction with liver atrophy as well as thrombosis of extracorporeal circuits in dialysis or liver assist devices. Moreover, liver disease-related hypercoagulability may contribute to vascular disease in the increasingly common condition of non-alcoholic fatty liver disease. Despite the incidence of these problems, there are few widely accessible and practical laboratory tests to evaluate the risk of a hypercoagulable event in cirrhosis patients. Furthermore, there is little research on the use of commonly accepted anticoagulants in patients with liver disease. This article is a result of an international symposium on coagulation disorders in liver disease and addresses several areas of specific interest in hypercoagulation in liver disease. Critical areas lacking clinical information are highlighted and future areas of research interest are defined with an aim to foster clinical research in this field.

Exposure of mice to topical bovine thrombin induces systemic autoimmunity.

Bovine thrombin is used as an aid to hemostasis in medical and surgical procedures. At least 500,000 Americans are exposed to this therapeutic annually and reports suggest that exposure is associated with the development of autoreactive antibodies. To determine whether bovine thrombin can induce pathological autoimmunity we exposed nonautoimmune-prone galactose-alpha1-3-galactose-deficient mice to the two bovine thrombin preparations currently approved for use in the United States. We found that, like humans exposed to bovine thrombin, mice developed an immune response against the therapeutic and the xenogeneic carbohydrate galactose-alpha1-3-galactose, and some mice developed autoantibodies against clotting factors. Further, unexpectedly, a single exposure to this therapeutic also induced autoimmunity with features characteristic of systemic lupus erythematosus including antibodies against nuclear antigens, native DNA, double-stranded DNA, and cardiolipin. High levels of these autoantibodies correlated with glomerulonephritis in all mice evaluated. This autoimmune syndrome was detected in mice 15 weeks after a secondary exposure to bovine thrombin and female mice were found to develop the syndrome at a significantly greater frequency than males. Thus, these studies indicate that exposure to bovine thrombin preparations can induce a pathological systemic autoimmune syndrome with lupus-like serology.

Platelets induce sinusoidal endothelial cell apoptosis upon reperfusion of the cold ischemic rat liver.

BACKGROUND & AIMS: Sinusoidal endothelial cell (SEC) apoptosis is a central feature of reperfusion injury in liver transplantation. Platelet sequestration occurs after transplantation with possible deleterious effects. We tested the hypothesis that platelets mediate SEC apoptosis. METHODS: Livers were perfused after 24 hours of cold preservation in University of Wisconsin solution in an isolated perfused rat liver model. The perfusate contained isolated syngeneic red blood cells and purified platelets. Effects of inhibiting platelet adhesion on SEC apoptosis was tested using sialyl Lewis-X oligosaccharide (sLe(x)), a natural ligand of selectin adhesion molecules. Reperfusion injury was assessed by established markers of injury. Apoptosis was determined by TUNEL and electron microscopy. RESULTS: A third of the circulating platelets was rapidly sequestered in the liver after reperfusion. This was associated with increased graft injury. Single platelets were adherent to sinusoidal lining without morphological or dynamic evidence of impairment of microcirculation. TUNEL staining revealed a 6-fold increase in the number of apoptotic SECs at 1 hour of reperfusion. No hepatocyte death or evidence of necrosis was detected up to 3 hours of reperfusion. Addition of sLe(x) inhibited adhesion and significantly reduced SEC apoptosis. CONCLUSIONS: Platelets cause SEC apoptosis upon reperfusion of liver grafts. Prevention of adhesion is protective.

Lack of association between early childhood immunizations and beta-cell autoimmunity.

OBJECTIVE: To determine whether early childhood immunization history affects the risk of developing the beta-cell autoimmunity that precedes type 1 diabetes. RESEARCH DESIGN AND METHODS: This article describes a case-control study whose participants were 317 children aged < or = 12 years who have a first-degree relative with type 1 diabetes. The children were enrolled in a prospective cohort study of the etiology of beta-cell autoimmunity, the Diabetes Autoimmunity Study in the Young, in Denver, Colorado. The main outcome measure was beta-cell autoimmunity as determined by persistent autoantibodies against insulin, GAD, or islet cell antibody (IA-2) 512. The number of cases with beta-cell autoimmunity was 25, and the number of control subjects (the remainder of the cohort) was 292. RESULTS: There was no difference between cases and control subjects in the proportion receiving hepatitis B (HBV), Haemophilus influenzae b (Hib), polio, or diphtheria tetanus pertussis (DTP) vaccines before 9 months of age; in the proportion receiving HBV at birth rather than later; or in the median age at first HBV, Hib, polio, or DTP vaccination. CONCLUSIONS: The results suggest that changing the early childhood immunization schedule would not affect the risk of developing beta-cell autoimmunity or type 1 diabetes.

Tissue factor de-encryption: ionophore treatment induces changes in tissue factor activity by phosphatidylserine-dependent and -independent mechanisms.

Coagulation is initiated on tissue-factor-bearing cells when factor VIIa complexes with membrane-bound tissue factor and activates factors X and IX. Cellular tissue factor activity does not correlate with tissue factor antigen; treatment with calcium ionophore rapidly increases tissue factor activity without increasing tissue factor antigen. Our study examined the effect of calcium ionophore A23187 on tissue factor activity of freshly isolated, lipopolysaccharide-stimulated monocytes and non-transformed human dermal fibroblasts. A23187 increased tissue factor activity on monocytes and fibroblasts in a dose-dependent fashion between 0.1 and 50 micromol/l ionophore. This increase in activity was proportional to an increase in intracellular calcium in monocytes. The increase in tissue factor activity was partially attributable to an increase in phosphatidylserine expression, as measured by increased prothrombinase activity (1.1- to 4-fold) on ionophore-treated cells. The phosphatidylserine-binding protein annexin V decreased tissue factor activity on both ionophore-treated and untreated cells, reflecting the role of phosphatidylserine in tissue factor activity. However, even in the presence of saturating concentrations of annexin V, the tissue factor activity of ionophore-treated cells was 1.3- to 11.3-fold higher than that of untreated cells, indicating that the increase in tissue factor activity did not result solely from increased expression of phosphatidylserine. A23187 increased tissue-factor-dependent activation of factors IX and X 1.4- to 7-fold on both cell types, indicating that ionophore treatment did not alter factor VIIa/tissue factor substrate specificity. We conclude that the mechanism by which calcium ionophore increases tissue factor activity is not unique to monocytoid or transformed cells. Furthermore, the ionophore-induced increase in activity is not solely the result of increased exposure to phosphatidylserine. Finally, tissue factor de-encryption by A23187 does not alter factor VIIa/tissue factor substrate specificity.

Platelets from thrombocytopenic ponies acutely infected with equine infectious anemia virus are activated in vivo and hypofunctional.

Thrombocytopenia is a consistent finding and one of the earliest hematological abnormalities in horses acutely infected with equine infectious anemia virus (EIAV), a lentivirus closely related to human immunodeficiency virus. Multifactorial mechanisms, including immune-mediated platelet destruction and impaired platelet production, are implicated in the pathogenesis of EIAV-associated thrombocytopenia. This study was undertaken to investigate whether regenerative thrombopoiesis and platelet destruction occurred in ponies acutely infected with EIAV. Circulating large, immature platelets were increased in ponies acutely infected with EIAV late in the infection when platelet count was at a nadir. Morphometric analysis of bone marrow from acutely infected ponies revealed significant increased in megakaryocyte area and megakaryocyte nuclear area. A trend toward increased numbers of megakaryocytes was also observed. Platelets from acutely infected ponies had increased surface-bound fibrinogen and ultrastructural changes consistent with in vivo platelet activation. Platelets also had hypofunctional aggregation responses to three agonists in vitro. We conclude that thrombocytopenia in ponies acutely infected with EIAV is regenerative and suggest that bone marrow platelet production is not severely compromised in these ponies. Our findings reveal that in vivo platelet activation occurs in ponies acutely infected with EIAV, and as a result platelets are hypofunctional in vitro. Activation of platelets in vivo may cause platelet degranulation or formation of platelet aggregates, which would result in removal of these damages platelets from circulation. This may represent a form of nonimmune-mediated platelet destruction in ponies acutely infected with EIAV.

Heparin cofactor II and thrombin Heparin-binding proteins linking hemostasis and inflammation.

α-Thrombin is a trypsinlike serine proteinase involved in blood coagulation and wound-healing processes, which interacts with many different macromolecular substances. Heparin cofactor II is a serpin (serine proteinase inhibitor) superfamily member that specifically inhibits thrombin but no other proteinase in blood coagulation. Both heparin cofactor II and thrombin interact with highly negatively charged glycosaminoglycans like heparin and dermatan sulfate, and they both are leukocyte chemoattractants. The focus of this brief review is structure-function characteristics of heparin cofactor II and thrombin and their physiologic participation in uniting hemostatic and inflammatory processes.

Reversible binding of platelet-derived growth factor-AA, -AB, and -BB isoforms to a similar site on the "slow" and "fast" conformations of alpha 2-macroglobulin.

The mechanism by which the platelet-derived growth factor (PDGF)-binding protein, alpha 2-macroglobulin (alpha 2M), modulates PDGF bioactivity is unknown, but could involve reversible PDGF-alpha 2M binding. Herein we report that greater than 70% of 125I-PDGF-BB or -AB complexed to alpha 2M was dissociated by SDS-denaturation followed by SDS-polyacrylamide gel electrophoresis, i.e. most of the binding was noncovalent. Reduction of the PDGF.alpha 2M complex following denaturation dissociated the cytokine from alpha 2M by greater than 90%, suggesting covalent disulfide bond formation. Approximately 50% of the growth factor was dissociated by lowering the pH from 7.5 to 4.0. 125I-PDGF-BB bound alpha 2M in a time-dependent manner (t1/2 = approximately 1 h), reaching equilibrium after 4 h. The 125I-PDGF.BB/alpha 2M complex dissociated more slowly (t1/2 = approximately 2.5 h). "Slow" and "fast" alpha 2M bound nearly equal amounts of PDGF-AB or -BB. Trypsin treatment converted PDGF-BB/alpha 2M complex to the fast conformation but did not release bound 125I-PDGF-BB. All PDGF-isoforms (AA, -AB, and -BB) competed for binding with 125I-PDGF-BB binding to slow alpha 2M and fast alpha 2M-methylamine by 65-80%. Other cytokines that bind alpha 2M (transforming growth factor-beta 1 and -beta 2, tumor necrosis factor-alpha, basic fibroblast growth factor, interleukin -1 beta, and -6) did not compete for 125I-PDGF-BB binding slow alpha 2M, but transforming growth factor-beta 1 and basic fibroblast growth factor inhibited 125I-PDGF-BB binding alpha 2M-methylamine by 30-50%. The reversible nature of the PDGF.alpha 2M complex could allow for targeted PDGF release near mesenchymal cells which possess PDGF receptors.

Effect of interferon-gamma and human alpha 2-macroglobulin on peritoneal macrophage morphology and Ia antigen expression.

While the primary role of the plasma protein alpha 2-macroglobulin (alpha 2M) appears to be related to its proteinase inhibitory activity, alpha 2M has been reported to regulate the immune response in vitro. Previous studies have demonstrated that, although native alpha 2M has no effect on macrophage function, proteinase- or CH3NH2-treated alpha 2M antagonize the IFN-gamma-induced expression of class II major histocompatibility complex (Ia) antigens on mouse peritoneal macrophages. In this investigation, we examined the effects of alpha 2M-CH3NH2 on the IFN-gamma-induced expression of macrophage Ia antigens by indirect immunofluorescence microscopy, radioimmunoassay, and immunoprecipitation of biosynthetically-labelled Ia. While alpha 2M-CH3NH2 suppressed the IFN-gamma induced increase in the percentage of Ia-positive macrophages detected by immunofluorescence microscopy, alpha 2M-CH3NH2 had no effect on the average of number of Ia molecules expressed per cell as detected by radioimmunoassay. In addition, alpha 2M-CH3NH2 had no effect on the ability of IFN-gamma to induce biosynthesis of Ia. Microscopic examination of IFN-gamma-treated macrophages revealed that treatment with alpha 2M-CH3NH2 prevented IFN-gamma-induced changes in macrophage morphology. IFN-gamma-treatment of elongated inflammatory macrophages was associated with the generation of round cells which possessed few cytoplasmic projections. By contrast, addition of alpha 2M-CH3NH2 to the incubation prevented the IFN-gamma-induced morphological changes, and the cells remained elongated with irregular cytoplasmic borders. We postulate that alpha 2M-CH3NH2 decreases the IFN-gamma-induced expression of Ia by preventing morphological changes in macrophages, resulting in the distribution of existing Ia over a larger surface area. As a consequence of this, the perceived fluorescence intensity of the bound antibody is lowered and the cells appear to be Ia-negative.

Modulation of mouse peritoneal macrophage Ia and human peritoneal macrophage HLA-DR expression by alpha 2-macroglobulin "fast" forms.

alpha 2-Macroglobulin (alpha 2M) is converted from its native form into electrophoretically "fast" forms by reaction with proteinases or with methylamine. The "fast" forms both bind to specific receptors on macrophages (MP). We have previously shown that alpha 2M "fast" forms modulate effector functions of murine peritoneal MP. In the present study, alpha 2M "fast" forms antagonized the increase in MP HLA-DR and Ia expression induced in vitro by interferon-gamma (IFN-gamma). This effect was observed with human peritoneal MP, as well as MP from peptone-injected and bacillus Calmette-Guérin-infected mice of three strains. alpha 2M-trypsin, which had been reacted with aprotinin and alpha 2M-methylamine, both of which lack proteolytic activity, also antagonized interferon-induced Ia expression. alpha 2M "fast" forms also reduced the ability of MP to serve as accessory cells for lectin-induced lymphocyte proliferation. alpha 2M "fast" form is an immune modulator of human and murine MP function, probably through a specific receptor-mediated mechanism.