bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Doses of Methylene Blue/Light Treatment Crosslink the A-Alpha-Subunit of Fibrinogen: Influence of This Photooxidization on Fibrinogen Binding to Platelets
Authors: Lorenz M. , Müller M. , Jablonka B. , Vigh T. , Kirchmaier C.M. 
Published: April 2003

Irradiation in the presence of 1 µM methylene blue (MB) inactivates enveloped viruses in human plasma. This method is a useful tool to enhance the safety of human fresh-frozen plasma in blood donor banks. Via a photooxidative mechanism, viral structures as well as plasma proteins, especially fibrinogen, can be damaged. We investigated the effect of MB/light-induced photooxidative modification on the structure of fibrinogen and its function in the interaction with platelets in the concentration range of 1–50 µM MB. Densitometric scanning of reduced SDS-PAGE showed a decrease in the Aα-subunit of fibrinogen as well as an increase in high-molecular-weight (HMW) aggregates with increasing MB concentrations. The HMW aggregates may be due to covalent crosslinking of single Aα-subunits via photooxidation induced by MB/light treatment. Fibrinogen treated with high doses of MB (50 µM) showed a weaker binding to the fibrinogen receptor (GP IIb/IIIa) on the platelet surface and a decrease in platelet aggregation after stimulation with ADP and photooxidized fibrinogen. These effects were not detected in fibrinogen isolated from virus-inactivated plasma (1 µM MB). This was in agreement with normal binding of fibrinogen to GP IIb/IIIa on platelets.
Activated Recombinant Human Coagulation Factor VII Therapy for Intracranial Hemorrhage in Patients with Hemophilia A or B with Inhibitors
Authors: Arkin S. , Cooper H.A. , Hutter J.J. , Miller S. , Schmidt M.L. , Seibel N.L. , Shapiro A. , Warrier I. 
Published: April 2003

Activated recombinant human coagulation factor VII (rFVIIa) is a promising new therapeutic agent for patients with hemophilia A or B with inhibitors who experience serious bleeding episodes or who need coverage during surgical procedures. This open-label, uncontrolled, emergency-use study evaluated the efficacy and safety of rFVIIa in 11 hemophiliac patients and 1 FVII-deficient patient with life-threatening intracranial hemorrhage previously unresponsive to one or more alternative therapies. rFVIIa effectively controlled intracranial hemorrhage in 10 of the 12 patients. Patients with hemophilia A or B received an average of 96.9 rFVIIa injections over 14.7 days with a mean total administration of 153.3 mg, corresponding to 8.1 mg/kg. Most reported adverse events were considered to be unrelated to rFVIIa therapy. These findings suggest that rFVIIa is an effective and well-tolerated therapeutic option in the management of central nervous system bleeding in patients with hemophilia A or B with inhibitors.
Hemorheological Profile in Chronic Venous Insufficiency after Surgery
Authors: Azaceta Gemma , Romero Soledad , Moreno Jose Antonio , Vaquerizo Alfonso , Olave Teresa , Lorente Cristina , Azcona Jose Miguel , Gutiérrez Martín 
Published: April 2003

In recent years, there have been rheological abnormalities reported in chronic venous insufficiency (CVI), mainly an increase of erythrocyte aggregability (EA), which probably take part in the pathophysiology of the disease. The aim of this study was to analyze the hemorheological profile after stripping in 45 patients suffering from CVI. Follow-up included laboratory tests on the 7th, 60th and 180th day after surgery. EA was assessed with a photometric aggregometer (MA1, Myrenne) in stasis and low shear (3 s<sup>–1</sup>). The results show an increase of EA on the 7th day after surgery (p < 0.001). Two and 6 months later, EA values returned to those found prior to surgery. The plasma fibrinogen level changes in a way parallel to EA. The association between rheological disturbances and thrombogenesis is well known, so the hyperaggregability found supports the antithrombotic prophylaxis in the early postsurgical period. On the other hand, the hemorheological abnormalities persist after stripping, so postsurgical treatment to inhibit EA may be beneficial.
Glucose-6-Phosphate Dehydrogenase Deficiency in Kuwait, Syria, Egypt, Iran, Jordan and Lebanon
Authors: Usanga Esien A. , Ameen Reem 
Published: April 2003

A total of 3,501 male subjects from six Arab countries living in Kuwait were investigated for quantitative and phenotypic distribution of red cell glucose-6-phosphate dehydrogenase (G6PD). The ethnic origins of those investigated were Kuwait, Egypt, Iran, Syria, Lebanon and Jordan. The distribution of G6PD deficiency among the different ethnic groups varied widely, ranging from 1.00% for Egyptians to 11.55% for Iranians. The activity of the normal enzyme was remarkably similar, with values ranging from 6.1 ± 0.8 to 6.5 ± 1.1 IU/g Hb. A low frequency of the <i>Gd</i><sup>A</sup> allele was found in two ethnic groups, Egyptians (0.019) and Iranians (0.014). <i>Gd</i><sup>A–</sup> was present at the very low frequency of 0.006 in another two ethnic groups, Kuwaitis and Jordanians.
Association Tests for Traits with Variable Age at Onset
Authors: Mokliatchouk Oksana , Blacker Deborah , Rabinowitz Daniel 
Published: April 2003

This paper is concerned with testing association between marker genotypes and traits with variable age at onset. Two methods are proposed, one which makes use of both age-at-ascertainment and age-at-onset information, and one which may be applied when only age-at-ascertainment information is available. (Here, by age-at-ascertainment, is meant the subject’s age when presence of onset and age at onset are determined; for subjects who have died or are otherwise censored before ascertainment, the censoring time should be used instead). Adjustment for confounding due to population stratification is carried out by conditioning on observed traits and parental genotypes, or, if complete parental genotypes are not available, by conditioning on observed traits and the minimal sufficient statistics under the null hypothesis for the parental genotypes. Proportional hazards regression models and logistic regression models are used to motivate the methods, but correct type I error rates result even if the models are not correct. An illustrative example is described.
Effect of Ca<sup>2+</sup> ATPase Inhibitors on MCP-1 Release from Bone Marrow-Derived Mast Cells and the Involvement of p38 MAP Kinase Activation
Authors: Teshima R. , Onose J. , Okunuki H. , Sawada J. 
Published: April 2003

The effect of two Ca<sup>2+</sup> ATPase inhibitors, cyclopiazonic acid (CPA) and 2,5-di-(tert-butyl)-1,4-hydroquinone (DTBHQ), on the release of MCP-1 from bone marrow-derived mast cells (BMMCs) were investigated. CPA and DTBHQ increased the intracellular free Ca<sup>2+</sup> concentration ([Ca<sup>2+</sup>]<sub>i</sub>) and induced MCP-1 release in a dose-dependent manner. These Ca<sup>2+</sup> ATPase inhibitors induced MCP-1 release in the absence of phorbol ester, in contrast to their induction of TNF-α. MCP-1 release reached a maximum at 6–9 h. It was inhibited by treatment with actinomycin D, the immunosuppressant cyclosporin A, and the cytosolic Ca<sup>2+</sup> chelator BAPTA-AM. Furthermore, RT-PCR showed a time-dependent increase of MCP-1 mRNA. Thus MCP-1 release seems to depend on Ca<sup>2+</sup>-dependent transcriptional activation. MCP-1 release was dose-dependently inhibited by the p38 MAP kinase inhibitor SB202190, but not by the p44/42 MAP kinase inhibitor PD98059. Therefore, transcriptional activation of MCP-1 production and its release seem to be dependent on the nuclear factor of activated T cells and p38 MAP kinase activation. This is the first report to show the regulation of MCP-1 production in BMMCs.
Effect of Suplatast Tosilate (IPD-1151T) on a Mouse Model of Asthma: Inhibition of Eosinophilic Inflammation and Bronchial Hyperresponsiveness
Authors: Zhao Guang-Dong , Yokoyama Akihito , Kohno Nobuoki , Sakai Kimiko , Hamada Hironobu , Hiwada Kunio 
Published: April 2003

<i>Background:</i> Suplatast tosilate (IPD) is a newly developed ‘anti-allergic’ drug. It seems to be a unique compound because of its ability to suppress IgE but not IgG or IgM production in vivo and cytokine production from type 2 helper T cells (Th2) in vitro. However, information on its in vivo effect on an animal model of asthma is limited. <i>Method:</i> BALB/c mice sensitized to ovalbumin (3 times, 2-week interval) were challenged with ovalbumin by inhalation (50 mg/ml for 20 min, once a day for 6 days). In this study, we explored the influence of IPD on eosinophil infiltration into the airways, bronchial hyperresponsiveness (BHR) to methacholine, specific IgE antibody production, and cytokines in bronchoalveolar lavage fluid (BALF) using this murine model. <i>Results:</i> Treatment with IPD significantly reduced the number of total cells and eosinophils in BALF (around –40%) and almost completely inhibited the development of antigen-induced BHR. Histological findings confirmed the reduction of submucosal cell infiltration in the lung, and disclosed the marked inhibition of bronchial epithelial cell damage. Ovalbumin-specific IgE was slightly but significantly reduced. The levels of IL-4, IL-5 and IL-13 in BALF were significantly decreased in mice treated with the compound compared to those in untreated mice. <i>Conclusion:</i> These results suggest that IPD is capable of inhibiting the production of Th2 cytokines, which inhibit eosinophil infiltration into the murine airway, IgE synthesis, and development of BHR, in a murine model of asthma.
β-Estradiol Suppresses T Cell-Mediated Delayed-Type Hypersensitivity through Suppression of Antigen-Presenting Cell Function and Th1 Induction
Authors: Salem Mohamed Labib , Matsuzaki Goro , Kishihara Kenji , Madkour Gamal A. , Nomoto Kikuo 
Published: April 2003

<i>Background:</i> Although an immunomodulatory role for estrogens has long been demonstrated by experimental and clinical observations, the mechanism by which estrogens exert their effect on T cells has not been clearly defined. <i>Methods:</i> In this study we analyzed the effects of β-estradiol (E2), at its contraceptive dose, on the delayed-type hypersensitivity (DTH) to purified protein derivatives (PPD) and associated immune response in female mice. <i>Results:</i> E2 treatment decreased PPD-specific DTH response, which coincided with a decrease in the leukocytes numbers in the draining lymph nodes (DLN) and spleen compared with control mice. E2 treatment also suppressed the in vitro PPD-specific proliferative response of DLN and spleen cells from PPD-primed mice. The analysis of production and gene expression of cytokines by DLN cells demonstrated that E2 treatment suppressed IL-2 and IFN-γ production in response to PPD in vitro. In contrast, IL-4 and IL-10 gene expression by DLN cells of E2-treated mice, taken 24 h after in vivo restimulation of mice with PPD, was enhanced. Furthermore, we found that spleen APC from E2-treated mice failed to induce optimum proliferation of the PPD-primed T cells in response to PPD in vitro. The impaired APC function by E2 was not due to induction of suppressor cell activity because addition of the normal spleen APC to APC from E2-treated mice restored the proliferative response of the PPD-primed T cells in response to PPD. <i>Conclusion:</i> Our results suggest that the E2-mediated inhibition of DTH reaction is due to a combination of the down regulation of APC function and deviation of the immune response from Th1-type to Th2-type.
Effects of Mizolastine in vitro on Human Immunocompetent and Airway Cells: Evidence for Safety and Additional Property
Authors: Oddera S. , Cagnoni F. , Dellacasa P. , Canonica G.W. 
Published: April 2003

<i>Background:</i> Mizolastine is a potent, peripherally acting, selective H1-receptor antagonist with potential anti-inflammatory properties. The aim of the study was to evaluate the in vitro effects of mizolastine on the expression of adhesion molecules by primary human airway epithelial and stromal cultures; moreover, the activity of mizolastine on parameters which reflect the immune response efficacy was investigated. <i>Methods:</i> Airway epithelial and stromal cells were collected from hypereosinophilic subjects by enzymatic digestion of polyps or turbinates. Cells were stimulated with interferon (IFN)-γ (500 IU/ml) in the presence of various mizolastine concentrations (6 × 10<sup>–8</sup>–6 × 10<sup>–6</sup> <i>M</i>) for 24 h and the expression of CD106, CD54, CD58 and HLA class I was evaluated. Peripheral blood mononuclear cells from healthy volunteers were incubated with 1% phytohemagglutinin or anti-CD3 monoclonal antibody (20 ng/ml) in the presence of mizolastine, then T lymphocyte proliferation, HLA-DR expression and T cell subpopulations were evaluated. <i>Results:</i> Both in epithelial and stromal cultures, IFN-γ significantly upregulated all of the tested surface molecules (p < 0.05). The highest dose of mizolastine (6 × 10<sup>–6</sup> <i>M</i>), corresponding to 10-fold the peak plasma level after a single oral administration of 10 mg, was able to act on fibroblasts, significantly downregulating the expression of CD54 (p < 0.05). Regarding T lymphocyte proliferation, the addition of mizolastine did not induce any significant change; furthermore, mizolastine was ineffective at all of the tested concentrations on both HLA-DR expression and CD4+/CD8+ ratio. <i>Conclusions:</i> This study demonstrated that mizolastine is able to selectively downregulate CD54 expression on stimulated stromal but not epithelial cells without impairing the immune system effectors. The possible clinical significance of these results are an antiallergic property and CD54 modulation on fibroblasts with a good safety profile as far as the lymphocyte response is concerned.
Voltage-Gated Sodium Channels in Human Aortic Smooth Muscle Cells
Authors: Cox R.H. , Zhou Z. , Tulenko T.N. 
Published: April 2003

Whole-cell, voltage clamp methods were used to study inward currents in human aortic smooth muscle cells in culture. Cells were plated on glass coverslips, cultured in supplemented M-199 media with 5% serum and studied as primary cells and at passages 2–5. Inward currents were measured with a pipette solution containing Cs<sup>+</sup> and TEA<sup>+</sup> to block K<sup>+</sup> currents and with 2.5 m<i>M</i> [Ca<sup>2+</sup>]&#8320; in the perfusate. Inward currents activated at about –50 mV, peaked at about –15 mV and reversed at about +30 mV. Values of peak inward current averaged 14.7 ± 3.3 pA/pF and cell capacitance averaged 124 ± 10 pF (n = 35). These currents activated rapidly with a time-to-peak current of 2.4 ± 0.3 ms at a test potential of –10 mV from a holding potential of –80 mV. The current also inactivated rapidly with a time course that could be described by two components with time constants of 1.8 ± 0.2 and 17.8 ± 3.5 ms at –10 mV. The currents decreased when extracellular Na<sup>+</sup> was reduced and were completely inhibited by 50 n<i>M</i> tetrodotoxin (TTX), suggesting that they represented voltage-gated Na<sup>+</sup> currents (I<sub>Na</sub>). Activation curves were characterized with a V<sub>0.5</sub> = –16.6 ± 2.4 mV and a slope factor k = –5.2 ± 0.2 mV while inactivation curves were characterized with a V<sub>0.5</sub> = –60.9 ± 1.7 mV and a slope factor k = 8.8 ± 0.4 mV. Lowering external [Ca<sup>2+</sup>] to zero increased the maximum I<sub>Na</sub>, shifted its voltage dependence in the hyperpolarizing direction and increased the rate of I<sub>Na</sub> inactivation. Increasing external [Ca<sup>2+</sup>] or [Mg<sup>2+</sup>]decreased I<sub>Na</sub> and slowed its rate of inactivation. These studies demonstrate the presence of voltage-gated Na<sup>+</sup> channels with high TTX sensitivity that are modulated by extracellular divalent cations in human aortic smooth muscle cells maintained in cell culture. Window currents were found in the voltage range of –50 to –20 mV, suggesting that these channels could contribute to the resting membrane potential.
Evidence for the Involvement of Protein Kinase C in Depression of Endothelium-Dependent Vascular Responses in Spontaneously Hypertensive Rats
Authors: Soloviev A.I. , Parshikov A.V. , Stefanov A.V. 
Published: April 2003

The goal of the present study was to evaluate the role of protein kinase C (PKC) in the depression of endothelium-dependent vacular response in spontaneously hypertensive Okamoto rats (SHR). Aortae from SHR demonstrated a decreased relaxant response to acetylcholine (Ach) as compared to aortae from normotensive Wistar-Kyoto (WKY) rats, while papaverine lowered the force of aorta to a similar degree in both strains of rats. PKC inhibitors, H-7 (5 × 10<sup>–6</sup> <i>M</i>) and chelerythrine chloride (10<sup>–6</sup> <i>M</i>), produced a greater decrease in the force developed by the aortae from SHR vs. WKY rats both in intact and chemically permeabilized tissues. In SHR aortae PKC inhibitors enhanced relaxation to Ach to a greater extent as compared to WKY aortae. Furthermore, in the presence of PKC inhibitors, the constrictor responses of SHR aortae to Ach were transformed into relaxant responses, and the concentration-response curve to Ach was shifted to the left. The sensitivity of aortae from SHR to authentic nitric oxide (NO) was lowere compared to WKY rats. EC<sub>50</sub>s for authentic NO in SHR and WKY rat aortae were different: –2.9 ± 0.15 × 10<sup>–6</sup> <i>M</i> and 4.58 ± 0.1 × 10<sup>–7</sup> <i>M</i> (n = 15, p < 0.001), respectively. Bioassay experiments using SHR aortae showed that the addition of chelerythrine (10<sup>–6</sup> <i>M</i>) to the detector superfusate caused relaxation during treatment of the donor segment with Ach, indicating that the sensitivity of the aortae to NO had been restored. When SHR detector ring was substituted for denuded aortae from WKY rats and PKC inhibitors were not added to the detector superfusate, the relaxation of the detector aortae was also close to the normal Ach-induced relaxation. WKY aortae demonstrated a positive relationship between Ach-stimulated NO release and relaxant response amplitudes (correlation coefficient r = 0.905, p < 0.001, n = 10). In contrast, there was a significant negative correlation in SHR aortae (r = –0.712, p < 0.05, n = 10). Detection of NO release by chemiluminescence showed no significant difference in NO release in SHR and WKY aortae. Taken together, these data suggest that the blunted endothelium-dependent relaxations seen in SHR aortae are mainly due to a decreased sensitivity of vascular smooth muscle to EDRF/NO resulting from an increased PKC activity.
Regulation of Arachidonic Acid Release by Calcium Influx in Human Endothelial Cells
Authors: Millanvoye-Van Brussel Elisabeth , David-Dufilho Monique , Do Pham Thuc , Iouzalen Lahcen , Aude Devynck Marie 
Published: April 2003

In response to stimuli, endothelial cells release arachidonic acid, a lipid precursor of various vasoactive substances. We have investigated the relationships between cytosolic Ca<sup>2+</sup> movements and arachidonic acid release in human umbilical vein endothelial cells. Histamine, a receptor-dependent agonist, and thapsigargin, a specific inhibitor of sarco-/endoplasmic Ca<sup>2+</sup> pumps, time- and dose-dependently increased the release of [1-<sup>14</sup>C]-arachidonic acid. This release was inhibited by AACOCF<sub>3</sub>, a selective inhibitor of cytosolic phospholipase A<sub>2</sub> (PLA<sub>2</sub>). In the absence of Ca<sup>2+</sup> influx, arachidonic acid release was suppressed in both histamine- and thapsigargin-stimulated cells, despite marked elevations of cytosolic Ca<sup>2+</sup> concentration ([Ca<sup>2+</sup>]<sub>i</sub>). In the presence of Ca<sup>2+</sup> influx, arachidonic acid release was reduced in cells treated with BAPTA, an intracellular Ca<sup>2+</sup> buffer, or with SK&F 96365, a receptor-operated Ca<sup>2+</sup> channel blocker. Arachidonic acid release was analyzed as a function of the two successive phases of Ca<sup>2+</sup> response to stimulation: Ca<sup>2+</sup> peak and plateau phase, reflecting Ca<sup>2+</sup> mobilization from internal stores and Ca<sup>2+</sup> influx, respectively. The amount of arachidonic acid released was directly related to [Ca<sup>2+</sup>]<sub>i</sub> values measured at the influx phase with a 80 n<i>M</i> [Ca<sup>2+</sup>]<sub>i</sub> threshold, similar to that reported for PLA<sub>2</sub> translocation. This suggests that Ca<sup>2+</sup> entry from the extracellular space is essential for activating cytosolic PLA<sub>2</sub> in human endothelial cells.
Local Adenovirus-Mediated Delivery of Hirudin in a Rabbit Arterial Injury Model
Authors: Bishop Gregory G. , Wiegman Pete , McNamara Coleen , Din Salah , Sanders John , Hesselbacher Sean , Feldman Mike , McPherson John A. , Humphries John E. , Hammarskjold Marie-Louise , Gimple Lawrence W. , Ragosta Michael , Powers Eric R. , Dickek David , Owens Gary K. , Sarembock Ian J. 
Published: April 2003

Intravascular delivery of an E1/E3 deleted adenovirus encoding the hirudin protein reduces neointimal formation in the rat arterial injury model. Given the interspecies variability in response to adenoviral vectors, we tested this same construct in the hirudin-sensitive cholesterol-fed rabbit arterial balloon injury model. We hypothesized that local delivery of an E1/E3-deleted adenovirus encoding hirudin (Ad-Hir) in addition to early hirudin infusion would limit neointimal formation compared to early hirudin alone. <i>Methods and Results:</i> Local delivery of Ad-Hir, 2.5 × 10<sup>10</sup> PFU/ml, using a double balloon catheter [n = 6 vessels (v)] produced a 79% reduction in vessel wall thrombin activity at 48 h after balloon angioplasty (BA) compared with vehicle (Veh, n = 6v; p = 0.05). In chronic experiments, hypercholesterolemic rabbits underwent femoral BA, and received either early hirudin alone (n = 9v) or early hirudin plus locally delivered Ad-Hir (early hirudin + Ad-Hir; n = 9v), an E1/E3-deleted adenovirus encoding β-galactosidase (early hirudin + AdGal; n = 7v), or Veh (early hirudin + Veh; n = 10v). Early hirudin + Ad-Hir did not limit the arterial response to injury versus the other groups at 4 weeks after BA. Plaque area, cross-sectional luminal area narrowing by plaque, and T cell infiltration were significantly increased in the adenovirus- versus non-adenovirus-treated arteries. Plaque area correlated with T cell density. <i>Conclusion:</i> Following BA in cholesterol-fed rabbits, local transduction with A-Hir produced a marked reduction in vessel wall-associated thrombin activity. However, this strategy increased rather than decreased the arterial response to BA injury. Our results suggest that the lack of therapeutic effect resulted from adenovirus-stimulated plaque formation, possibly resulting from a T cell-mediated inflammatory response.