bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrathoracic Sporadic Desmoid Tumor with the Beta-Catenin Gene Mutation in Exon 3 and Activated Cyclin D1
Authors: Tajima Shunji , Hironaka Mitsugu , Oshikawa Katsuhisa , Bando Masashi , Ohno Shoji , Saito Ken , Sohara Yasunori , Sugiyama Yukihiko
Published: September 2005

We report a case of intrathoracic desmoid tumor without familial adenomatous polyposis and demonstrate beta-catenin mutation of exon 3. A 15-year-old male presented with a desmoid tumor after having sustained an assault. In an examination for a mutation of the beta-catenin gene, an activating mutation from ACC (Thr) to GCC (Ala) at codon 41 was found. Immunohistochemical staining showed that accumulated beta-catenin protein was predominantly localized in the nuclei of desmoid cells, and cyclin D1 protein was also overexpressed. These findings might suggest that an activating mutation of the beta-catenin gene affected regulation of the cyclin D1 gene, resulting in the generation of intrathoracic sporadic desmoid tumor, which arose at the site of posttraumatic injury.
Diffuse Idiopathic Neuroendocrine Cell Hyperplasia Causing Severe Airway Obstruction in a Patient with a Carcinoid Tumor
Authors: Adams Heiner , Brack Thomas , Kestenholz Peter , Vogt Peter , Steinert Hans C. , Russi Erich W.
Published: September 2005

We report a 57-year-old female with severe airway obstruction who underwent resection of a tumor of unknown dignity during lung volume reduction surgery. The nodule consisted of a well-differentiated neuroendocrine tumor (carcinoid), and severe chronic obstructive lung disease was due to diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, a very rare cause of obliterative bronchiolitis. Radionuclide ablative therapy of the neuroendocrine tissue was considered but not found to be feasible due to a low lung/background ratio of the radiotracer.
Pulmonary Infiltrates with Eosinophilia Induced by Nimesulide in an Asthmatic Patient
Authors: Perng Diahn-Warng , Su Hsuan-Tsung , Tseng Chih-Wei , Lee Yu-Chin
Published: September 2005

We report a case of pulmonary infiltrates with eosinophilia (PIE) induced by nimesulide in an asthmatic patient on regular inhaled corticosteroid treatment. A high level of eosinophils in induced sputum was detected. No evidence of bacterial or fungal infection was observed. The patient responded rapidly to corticosteroid treatment. Rechallenge with nimesulide induced blood and sputum eosinophilia, confirming our diagnosis. Nimesulide, though it is a relatively safe drug to use in aspirin-sensitive asthmatics, may (like other nonsteroidal anti-inflammatory drugs) cause PIE in asthmatic patients and thus should be used cautiously.
Amiodarone-Related Acute Respiratory Distress Syndrome following Sudden Withdrawal of Steroids
Authors: Charles Pierre-Emmanuel , Doise Jean-Marc , Quenot Jean-Pierre , Muller Géraldine , Aube Hervé , Baudouin Nicolas , Piard Françoise , Besancenot Jean-François , Blettery Bernard
Published: September 2005

Acute lung toxicity is a rare but classical complication of amiodarone therapy. We report the case of a patient who developed an optic neuropathy after 15 years of amiodarone administration, and who was treated for 2 weeks with steroids. Following withdrawal of steroids, the patient rapidly developed an acute respiratory distress syndrome. Postmortem lung histologic examination was consistent with amiodarone-induced pneumonitis. Since this complication is thought to be of immunological origin, we speculate that the sudden withdrawal of steroids was implicated in the development of the acute lung injury.
Apolipoprotein E Regulates Primary Cultured Human Mesangial Cell Proliferation
Authors: Zhang Yixiang , Yasumoto Yuichiro , Ikeda Toru , Takenouchi Syozo , Sogabe Atsushi , Nosaki Tsuyoshi , Che Xiaofang , Zheng Chunlei , Haraguchi Misako , Akiyama Shin-ichi , Tsubouchi Hirohito
Published: September 2005

Background: The role of apolipoprotein (apo) E in kidney disease is still unclear. Animal studies have been performed, but it is doubtful if the conclusions are applicable to human beings. The objective of this study was to determine how apo E acts on human kidneys using primary cultured normal human mesangial cells (NHMCs) rather than animals used in previous studies. Methods: apo E and its isoforms E2, E3 and E4, or combinations with apo B were cocultured with primary NHMCs in serum-free medium. Premix WST-1 Cell Proliferation Assay System and DNA-Prep Reagent System were used to measure the proliferation and apoptosis of NHMCs, respectively. Results: (1) apo E itself increased NHMC proliferation at 24 h of culture, while it inhibited this proliferation after 48 h. (2) At 72 h of culture, apo E alone inhibited NHMC proliferation at concentrations higher than 0.78 µg/ml in concentration-dependent manner. (3) When co-cultured with both apo E and apo B, NHMC proliferation was higher than that with apo E alone and lower than that with apo B alone. (4) At 72 h of culture, apo E2, E3 and E4 inhibited NHMC proliferation at different intensities, with no proliferative effect observed. (5) Neither apo E nor apo B caused NHMC apoptosis. Conclusion: apo E regulates primary NHMC proliferation by (1) inhibiting NHMC proliferation or reducing NHMC proliferation induced by apo B, which implies that apo E has a protective effect on the kidney, and (2) increasing the proliferation under certain conditions.
Development of a Sandwich-Type ELISA for Measuring Pla a 1, the Major Allergen of Platanus acerifolia Pollen
Authors: Arilla M.C. , Ibarrola I. , Mir A. , Monteseirín J. , Conde J. , Martínez A. , Asturias J.A.
Published: September 2005

Background:Platanus acerifolia is an important cause of pollinosis in Western European cities. Pla a 1, a nonglycosylated 18-kDa protein with a prevalence of 80%, is a major allergen in P. acerifolia pollen extracts. Our aim was to develop a Pla a 1-specific ELISA to quantify this protein in allergenic extracts and preparations for clinical use. Methods: Pla a 1 was purified by cation exchange at pH 7.0, gel filtration, and anion exchange chromatography at pH 10.0. Monoclonal (mAb) and polyclonal antibodies were obtained by immunizing mice and rabbits with nPla a 1. One (5C1) of the 13 mAb obtained was used as capture antibody at 5 µg/ml and biotin-labeled specific polyclonal antiserum at 0.63 µg/ml served for detection. Results: The prevalence of Pla a 1-specific IgE to purified Pla a 1 among 47 P. acerifolia-allergic patients was 79%. The Pla a 1-ELISA developed has a linear range of 3–25 ng/ml, high sensitivity with a detection limit of 0.5 ng/ml and is highly specific as none of the 24 pollen, mite, mold, and plant food extracts tested gave positive results. The assay could quantify Pla a 1-like proteins in other planetree pollen extracts. A good correlation was obtained between Pla a 1 content of 11 P. acerifolia pollen extracts (average content 0.69% of the total protein) and their IgE-binding activity. Conclusions: The described two-site sandwich ELISA to measure Pla a 1 is useful for standardization of planetree pollen extracts intended for clinical use.
A Vacuolar Serine Protease (Rho m 2) Is a Major Allergen of Rhodotorula mucilaginosa and Belongs to a Class of Highly Conserved Pan-Fungal Allergens
Authors: Chou Hong , Tam Ming F. , Lee Shinn-Shing , Tai Hsiao-Yun , Chang Ching-Yun , Chou Chang-Ter , Shen Horng-Der
Published: September 2005

Background:Rhodotorula mucilaginosa is one of the most frequently encountered species of yeasts in our environment. We reported here a major allergen of R. mucilaginosa. Methods: A major R. mucilaginosa allergen (Rho m 2) was characterized by two-dimensional (2D) immunoblotting, protein sequencing, cDNA cloning and IgE cross-reactivity with fungal serine proteases. Results: Fourty-four sera (28%) from 157 bronchial asthmatic patients showed IgE-immunoblot reactivity against R. mucilaginosa extract. Among these 44 sera, 25 (57%) demonstrated IgE binding against a 31-kDa protein of R. mucilaginosa. Protein sequencing results suggest that it is a vacuolar serine protease. The corresponding cDNA clone encoding a mature protein of 312 residues was isolated. It shares 67–68% sequence identity with vacuolar serine protease allergens from three different Penicillium species (Pen ch 18, Pen o 18 and Pen c 18) and designated as Rho m 2 by the Allergen Nomenclature Committee. The native and recombinant Rho m 2 react with IgE antibodies and monoclonal antibody (MoAb) FUM20 against fungal serine proteases. IgE cross-reactivity between nRho m 2 and nPen ch 18 was observed. It was also detectable between rRho m 2 and rPen o 18. Conclusion: Our results suggest that R. mucilaginosa may also be a significant causative agent of human respiratory allergic disorders. We identified a vacuolar serine protease as a major allergen of R. mucilaginosa (Rho m 2) and a pan allergen of prevalent airborne fungal species. We detected IgE cross-reactivity among these highly conserved serine protease pan-fungal allergens.
Apoptosis and Loss of Adhesion of Bronchial Epithelial Cells in Asthma
Authors: Trautmann Axel , Krüger Katja , Akdis Mübeccel , Müller-Wening Dietrich , Akkaya Ahmet , Bröcker Eva-B. , Blaser Kurt , Akdis Cezmi A.
Published: September 2005

Background: Asthma is an inflammatory airway disease associated with infiltration of T cells and eosinophils, increased levels of pro-inflammatory cytokines, and shedding of bronchial epithelial cells (EC). We have recently shown that T cells and eosinophils cooperate in inducing bronchial EC apoptosis in asthma through secretion of IFN-γ and TNF-α. Since EC shedding is a histologic hallmark of asthma, the intercellular junction of EC may be a target of pro-inflammatory cytokines. Methods: Bronchial EC, cultured and exposed to IFN-γ and TNF-α, were studied for the expression of adhesion molecules and apoptosis. In addition, the epithelial layer of bronchial biopsies from asthma patients was evaluated for apoptosis, shedding, and expression of adhesion molecules. Results: We demonstrate that the induction of EC apoptosis is accompanied by loss of E-cadherin. In situ examination of E-cadherin in asthma revealed a reduction in its expression on EC membranes. In contrast, the in vitro and in vivo expression of β1-integrins and intercellular adhesion molecule-1 (ICAM-1) increased on EC during asthmatic airway inflammation. Conclusions: Loss of cadherin-mediated intercellular adhesion and apoptosis could account for fragility and shedding of EC in asthma, especially since this occurs between columnar and basal EC.
Association of Transforming Growth Factor-β1 Single Nucleotide Polymorphism C-509T with Allergy and Immunological Activities
Authors: Meng Jianfeng , Thongngarm Torpong , Nakajima Mikio , Yamashita Naomi , Ohta Ken , Bates Christopher A. , Grunwald Gary K. , Rosenwasser Lanny J.
Published: September 2005

Background: A single nucleotide polymorphism (SNP) C-509T within the tumor growth factor β1 (TGFβ1) gene has been associated with atopic asthma and asthma severity. To further understand the mechanisms involved, the association of C-509T with allergy, T-lymphocyte proliferation and plasma TGFβ1 concentration has been explored in a case-control study with allergic and non-allergic subjects. Methods: The recruited subjects including allergic (n = 38) and nonallergic (n = 25) participants have been genotyped for C-509T using allele discrimination assay. Association of C-509T with allergy status was examined using logistic regression analysis in both dominant and recessive models. Association of C-509T with T-cell proliferation in control and antigen-stimulated peripheral blood mononuclear cells (PBMCs), plasma TGFβ1 and total IgE level were tested by multiple regression analysis. Results: Individuals with homozygous mutant TT genotype showed a higher risk of allergy (TT: odds ratio = 5.099, 95% confidence limit: 1.355–19.190, p = 0.016) after covariates were adjusted. A trend to increased plasma TGFβ1 in subjects with T allele has been discovered. In the meantime, the T allele is associated with lower T cell proliferation in controls and maximum response to above antigens. A low T-cell proliferation is correlated with higher plasma TGFβ1 concentration (p < 0.01). The in vitro studies confirmed the suppressing effect of TGFβ1 on T-cell proliferation at physiological range. A significant inhibitory effect on IL-4 production was also observed. Conclusions: A C to T base change in TGFβ1 SNP C-509T has been associated with a higher risk of allergy. The mechanisms are not clear. Elevated TGFβ1 levels associated with the C-509T polymorphism might suppress immune activation as well as Th2 cytokine production.
Cardiac Tamponade due to Pneumopericardium
Authors: Trujillo Maximo H. , Fragachan Carlos F. , Tortoledo Francisco
Published: September 2005

We describe a newborn with acute respiratory distress syndrome, subjected to mechanical ventilatory assistance with high level of peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP), who developed cardiac tamponade due to pneumopericardium. Tension pneumopericardium produces the same physiological derangement as cardiac tamponade secondary to accumulated blood or other fluids. This life-threatening complication demands immediate diagnosis and treatment.
Cerebral Amyloid Angiopathy with Severe Secondary Vascular Pathology: A Histopathological Study
Authors: van Horssen Jack , de Jong Danielle , de Waal Robert M.W. , Maass Cathy , Otte-Höller Irene , Kremer Berry , Verbeek Marcel M. , Wesseling Pieter
Published: September 2005

Cerebral amyloid angiopathy (CAA) is a common neuropathological finding and is characterized by deposition of fibrillar amyloid in cortical and leptomeningeal vessels. In this study we describe the macroscopic and microscopic neuropathological findings of 5 patients with severe CAA-associated secondary vascular changes, including smooth muscle cell degeneration, hyalinization, ‘double-barreling’ phenomenon, macrophage infiltration, and aneurysmal dilatation of the vessel wall. In 3 of the 5 patients these vascular changes were associated with multiple small hemorrhages, whereas in 2 patients areas of ischemic necrosis were observed. However, none of these patients suffered from large (lobar) hemorrhagic accidents. Nevertheless, severe CAA, particularly when associated with secondary vascular pathology, may lead to vascular dementia-like ischemic changes. Hence, the distinction between patients with severe CAA and secondary vascular abnormalities from those suffering from vascular dementia can be difficult. We speculate that CAA, particularly when associated with secondary vascular pathology, although not resulting in large hemorrhages, may contribute to cognitive decline. The functional impact of CAA and CAA-related secondary vascular changes on cognitive performance warrants further exploration.
Ex vivo Evaluation of Tono-Pen and Pneumotonometry in Cat Eyes
Authors: Stoiber Josef , Fernandez Viviana , Lamar Peggy D. , Hitzl Wolfgang , Fantes Francisco , Parel Jean-Marie
Published: September 2005

Purpose: To evaluate the validity and intraobserver reliability of intraocular pressure (IOP) measurements with both pneumotonometry and the Tono-Pen in a closed ex vivo system in cat eyes. Methods: IOP was increased step by step in 5 enucleated cat eyes, while taking IOP measurements with the Tono-Pen and pneumotonometry. The outcomes were compared to readings of a digital manometer simultaneously measuring the actual pressure in the anterior chamber. Results: Pneumotonometry overestimated IOP below 15 mm Hg and underestimated pressures above 20 mm Hg. Tono-Pen tonometry considerably underestimated IOP over the whole spectrum in all of the eyes tested. The pneumotonometer was identified as the more valid and reliable instrument for cat eyes. Conclusion: Both tonometers are clinically useful tools to assess IOP for glaucoma studies using a cat animal model. However, one has to consider underestimation of IOP in the upper ranges. A correction formula can be used to calculate the actual IOP.
Lipopolysaccharide Upregulates Renal Shiga Toxin Receptors in a Primate Model of Hemolytic Uremic Syndrome
Authors: Clayton Frederic , Pysher Theodore J. , Lou Randall , Kohan Donald E. , Denkers Nathaniel D. , Tesh Vernon L. , Taylor Jr. Fletcher B. , Siegler Richard L.
Published: September 2005

Background: Although Shiga toxin (Stx) mediates classical hemolytic uremic syndrome (HUS), it is not fully understood why only some subjects exposed to Stx-expressing Escherichia coli develop HUS. We have previously shown in a baboon model of Stx-mediated HUS that coadministration of lipopolysaccharide (LPS) results in an augmented host response to otherwise subtoxic Stx1 doses. We used this model to test the hypothesis that LPS upregulates renal Stx receptor (Gb3) expression. Methods: Juvenile baboons were treated with either Stx1 (100 ng/kg), LPS (1 mg/kg as two divided doses 24 h apart), or a sham injection of saline, and sacrificed and immediately autopsied at 72 h. Renal cortical tissue Gb3 content was quantitated by lipid extraction and thin-layer chromatography, and Stx1 and Gb3/CD77 immunostaining was assessed by quantitative immunofluorescent microscopy. Results: Compared to saline-in jected controls, LPS administration resulted in a 2.2-fold increase in renal cortical Gb3 by chromatography (p < 0.01), a 2.5-fold increase in Stx1 staining (p = 0.003) and a 1.7-fold increase in CD77 immunostaining (p = 0.004). Stx treatment did not significantly alter either Stx or CD77 immunostaining. Conclusion: These observations suggest that LPS primes the host for Stx-mediated renal injury by upregulating renal Gb3 expression.
Color Doppler Flow Analysis of Uterine and Ovarian Arteries before and after Tubal Sterilization: Electrocautery versus Pomeroy
Authors: Dede F. Suat , Akyuz Ozden , Dilbaz Berna , Caliskan Eray , Haberal Ali
Published: September 2005

Background/Aim: To compare the changes in uterine and ovarian artery blood flow following laparoscopic sterilization via bipolar cautery with Pomeroy tubal ligation via mini-laparotomy in patients who had voluntary surgical sterilization. Methods: Ninety consecutive fertile women applying for voluntary tubal ligation were recruited in this prospective study. Patients were allocated for either laparoscopic tubal ligation via bipolar electrocoagulation (group 1) or Pomeroy tubal ligation via mini-laparotomy (group 2) according to their preference. Color Doppler flow analysis of uterine and ovarian arteries were carried out on the 3rd day of the cycle prior to the procedure (D₀), on the 3rd postoperative day (D1) and on the 3rd day of the cycle, 3 months (D3) following the surgery. The significance of difference between the three measurements was analyzed by using analysis of variance. Results: Prior to surgery, the mean pulsatility index of the uterine artery, left and right ovarian arteries were 1.9 ± 0.3, 1.8 ± 0.3, 1.8 ± 0.2 in group 1 and 1.8 ± 0.08, 1.8 ± 0.08, 1.8 ± 0.07 in group 2, respectively. There was no statistically significant difference between group 1 and group 2 in terms of D₀ values (p > 0.05). 3rd postoperative day and 3rd month measurements of both uterine and ovarian arteries in group 1 and group 2 did not show any statistically significant difference from that of preoperative values (p > 0.05). Conclusion: No alternation in the flow of either ovarian or uterine arteries following tubal sterilization performed by bipolar electrocautery and Pomeroy’s technique was determined both in the immediate postoperative period and 3 months after the surgery.
Transcription Factor SOX18 Is Expressed in Human Coronary Atherosclerotic Lesions and Regulates DNA Synthesis and Vascular Cell Growth
Authors: García-Ramírez Marta , Martínez-González José , Juan-Babot Josep O. , Rodríguez Cristina , Badimon Lina
Published: September 2005

Objective—

SOX18
, a member of the
SOX
gene family (SRY-like 3-hydroxy-3-methylglutaryl box gene), is a transcription factor expressed in the development of blood vessels during embryogenesis. We analyzed SOX18 expression in human coronary atherosclerotic lesions and investigated its potential function in vascular cells.

Methods and Results—

In advanced human coronary atherosclerotic lesions, SOX18 immunostaining was localized in endothelial cells (on the luminal surface, in vasa vasorum, and in intimal neovessels) and in vascular smooth muscle cells (VSMCs) scattered in the intima, colocalizing with proliferating cell nuclear antigen. In cell cultures, SOX18 was mainly localized in subconfluent and denuded areas. Significant
SOX18
mRNA levels (by Northern blot analysis and reverse transcription–polymerase chain reaction) were detected in cell cultures from human umbilical vein endothelial cells and human VSMCs. Antisense
SOX18
inhibited DNA synthesis ([
3
H]thymidine incorporation) and vascular cell growth. Antisense
SOX18
also significantly reduced VSMC regrowth after injury in an in vitro model of wound repair.

Conclusions—

Our results indicate that SOX18 is involved in vascular cell growth and suggest that this transcription factor may play a role in atherosclerosis.
Inhibition of the Renin-Angiotensin System Prevents Free Fatty Acid–Induced Acute Endothelial Dysfunction in Humans
Authors: Watanabe Saiko , Tagawa Tatsuya , Yamakawa Ken , Shimabukuro Michio , Ueda Shinichiro
Published: September 2005

Objective—

An elevated free fatty acid (FFA) level impairs endothelium-dependent vasodilation in humans, which may be pathophysiologically relevant to the development of endothelial dysfunction in patients with insulin resistance. We investigated the effect of inhibition of the renin-angiotensin system (RAS) on FFA-induced endothelial dysfunction.

Methods and Results—

Changes in forearm blood flow during intra-arterial infusion of acetylcholine were measured by plethysmography before and after systemic infusion of lipid/heparin in 10 healthy subjects given a single dose of placebo, losartan (50 mg), or perindopril (8 mg). Endothelial function after lipid/heparin infusion was also investigated with the coinfusion of vitamin C or
N
G
-monomethyl-
l
-arginine (L-NMMA). Elevated FFA significantly reduced the response to acetylcholine by 37.7% (
P
=0.0096) without L-NMMA, but not the response with L-NMMA, whereas FFA did not affect the response to nitroprusside. The single dose of either losartan or perindopril completely prevented FFA-induced endothelial dysfunction. Vitamin C also prevented FFA-induced endothelial dysfunction.

Conclusions—

Elevated FFA levels by lipid/heparin infusion, which may partly mimic the abnormal lipid profile in patients with insulin resistance, caused endothelial dysfunction via RAS activation and the presumably resultant oxidative stress in humans. Our results suggest the therapeutic rationale for RAS inhibition in patients with high FFA levels.
Stoichiometric Relationships Between Endothelial Tetrahydrobiopterin, Endothelial NO Synthase (eNOS) Activity, and eNOS Coupling in Vivo
Authors: Bendall Jennifer K. , Alp Nicholas J. , Warrick Nicholas , Cai Shijie , Adlam David , Rockett Kirk , Yokoyama Mitsuhiro , Kawashima Seinosuke , Channon Keith M.
Published: September 2005

Endothelial dysfunction in vascular disease states is associated with reduced NO bioactivity and increased superoxide (O
2
·−
) production. Some data suggest that an important mechanism underlying endothelial dysfunction is endothelial NO synthase (eNOS) uncoupling, whereby eNOS generates O
2
·−
rather than NO, possibly because of a mismatch between eNOS protein and its cofactor tetrahydrobiopterin (BH4). However, the mechanistic relationship between BH4 availability and eNOS coupling in vivo remains undefined because no studies have investigated the regulation of eNOS by BH4 in the absence of vascular disease states that cause pathological oxidative stress through multiple mechanisms. We investigated the stoichiometry of BH4–eNOS interactions in vivo by crossing endothelial-targeted eNOS transgenic (eNOS-Tg) mice with mice overexpressing endothelial GTP cyclohydrolase 1 (GCH-Tg), the rate-limiting enzyme in BH4 synthesis. eNOS protein was increased 8-fold in eNOS-Tg and eNOS/GCH-Tg mice compared with wild type. The ratio of eNOS dimer:monomer was significantly reduced in aortas from eNOS-Tg mice compared with wild-type mice but restored to normal in eNOS/GCH-Tg mice. NO synthesis was elevated by 2-fold in GCH-Tg and eNOS-Tg mice but by 4-fold in eNOS/GCH-Tg mice compared with wild type. Aortic BH4 levels were elevated in GCH-Tg and maintained in eNOS/GCH-Tg mice but depleted in eNOS-Tg mice compared with wild type. Aortic and cardiac O
2
·−
production was significantly increased in eNOS-Tg mice compared with wild type but was normalized after NOS inhibition with
N
ω-nitro-
l
-arginine methyl ester hydrochloride (L-NAME), suggesting O
2
·−
production by uncoupled eNOS. In contrast, in eNOS/GCH-Tg mice, O
2
·−
production was similar to wild type, and L-NAME had no effect, indicating preserved eNOS coupling. These data indicate that eNOS coupling is directly related to eNOS–BH4 stoichiometry even in the absence of a vascular disease state. Endothelial BH4 availability is a pivotal regulator of eNOS activity and enzymatic coupling in vivo.
Cardiac-Specific Ablation of the Na
+
-Ca
2+
Exchanger Confers Protection Against Ischemia/Reperfusion Injury
Authors: Imahashi Kenichi , Pott Christian , Goldhaber Joshua I. , Steenbergen Charles , Philipson Kenneth D. , Murphy Elizabeth
Published: September 2005

During ischemia and reperfusion, with an increase in intracellular Na
+
and a depolarized membrane potential, Ca
2+
may enter the myocyte in exchange for intracellular Na
+
via reverse-mode Na
+
-Ca
2+
exchange (NCX). To test the role of Ca
2+
entry via NCX during ischemia and reperfusion, we studied mice with cardiac-specific ablation of NCX (NCX-KO) and demonstrated that reverse-mode Ca
2+
influx is absent in the NCX-KO myocytes. Langendorff perfused hearts were subjected to 20 minutes of global ischemia followed by 2 hours of reperfusion, during which time we monitored high-energy phosphates using
31
P-NMR and left-ventricular developed pressure. In another group of hearts, we monitored intracellular Na
+
using
23
Na-NMR. Consistent with Ca
2+
entry via NCX during ischemia, we found that hearts lacking NCX exhibited less of a decline in ATP during ischemia, delayed ischemic contracture, and reduced maximum contracture. Furthermore, on reperfusion following ischemia, NCX-KO hearts had much less necrosis, better recovery of left-ventricular developed pressure, improved phosphocreatine recovery, and reduced Na
+
overload. The improved recovery of function following ischemia in NCX-KO hearts was not attributable to the reduced preischemic contractility in NCX-KO hearts, because when the preischemic workload was matched by treatment with isoproterenol, NCX-KO hearts still exhibited improved postischemic function compared with wild-type hearts. Thus, NCX-KO hearts were significantly protected against ischemia-reperfusion injury, suggesting that Ca
2+
entry via reverse-mode NCX is a major cause of ischemia/reperfusion injury.
NAD(P)H Oxidase 4 Mediates Transforming Growth Factor-β1–Induced Differentiation of Cardiac Fibroblasts Into Myofibroblasts
Authors: Cucoranu Ioan , Clempus Roza , Dikalova Anna , Phelan Patrick J. , Ariyan Srividya , Dikalov Sergey , Sorescu Dan
Published: September 2005

Human cardiac fibroblasts are the main source of cardiac fibrosis associated with cardiac hypertrophy and heart failure. Transforming growth factor-β1 (TGF-β1) irreversibly converts fibroblasts into pathological myofibroblasts, which express smooth muscle α-actin (SM α-actin) de novo and produce extracellular matrix. We hypothesized that TGF-β1–stimulated conversion of fibroblasts to myofibroblasts requires reactive oxygen species derived from NAD(P)H oxidases (Nox). We found that TGF-β1 potently upregulates the contractile marker SM α-actin mRNA (7.5±0.8-fold versus control). To determine whether Nox enzymes are involved, we first performed quantitative real time polymerase chain reaction and found that Nox5 and Nox4 are abundantly expressed in cardiac fibroblasts, whereas Nox1 and Nox2 are barely detectable. On stimulation with TGF-β1, Nox4 mRNA is dramatically upregulated by 16.2±0.8-fold (n=3,
P
<0.005), whereas Nox5 is downregulated. Small interference RNA against Nox4 downregulates Nox4 mRNA by 80±5%, inhibits NADPH-driven superoxide production in response to TGF-β1 by 65±7%, and reduces TGF-β1–induced expression of SM α-actin by 95±2% (n=6,
P
<0.05). Because activation of small mothers against decapentaplegic (Smads) 2/3 is critical for myofibroblast conversion in response to TGF-β1, we also determined whether Nox4 affects Smad 2/3 phosphorylation. Depletion of Nox4 but not Nox5 inhibits baseline and TGF-β1 stimulation of Smad 2/3 phosphorylation by 75±5% and 68±3%, respectively (n=7,
P
<0.0001). We conclude that Nox 4 mediates TGF-β1–induced conversion of fibroblasts to myofibroblasts by regulating Smad 2/3 activation. Thus, Nox4 may play a critical role in the pathological activation of cardiac fibroblasts in cardiac fibrosis associated with human heart failure.
Modulation of the Ca
2
Permeable Cation Channel TRPV4 by Cytochrome P450 Epoxygenases in Vascular Endothelium
Authors: Vriens J. , Owsianik G. , Fisslthaler B. , Suzuki M. , Janssens A. , Voets T. , Morisseau C. , Hammock B.D. , Fleming I. , Busse R. , Nilius B.
Published: September 2005

TRPV4 is a broadly expressed Ca
2+
-permeable cation channel in the vanilloid subfamily of transient receptor potential channels. TRPV4 gates in response to a large variety of stimuli, including cell swelling, warm temperatures, the synthetic phorbol ester 4α-phorbol 12,13-didecanoate (4α-PDD), and the endogenous lipid arachidonic acid (AA). Activation by cell swelling and AA requires cytochrome P450 (CYP) epoxygenase activity to convert AA to epoxyeicosatrienoic acids (EETs) such as 5,6-EET, 8,9-EET, which both act as direct TRPV4 agonists. To evaluate the role of TRPV4 and its modulation by the CYP pathway in vascular endothelial cells, we performed Ca
2+
imaging and patch-clamp measurements on mouse aortic endothelial cells (MAECs) isolated from wild-type and TRPV4
−/−
mice. All TRPV4-activating stimuli induced robust Ca
2+
responses in wild-type MAECs but not in MAECs isolated from TRPV4
−/−
mice. Upregulation of CYP2C expression by preincubation with nifedipine enhanced the responses to AA and cell swelling in wild-type MAECs, whereas responses to other stimuli remained unaffected. Conversely, inhibition of CYP2C9 activity with sulfaphenazole abolished the responses to AA and hypotonic solution (HTS). Moreover, suppression of EET hydrolysis using 1-adamantyl-3-cyclo-hexylurea or indomethacin, inhibitors of soluble epoxide hydrolases (sEHs), and cyclooxygenases, respectively, enhanced the TRPV4-dependent responses to AA, HTS, and EETs but not those to 4α-PDD or heat. Together, our data establish that CYP-derived EETs modulate the activity of TRPV4 channels in endothelial cells and shows the unraveling of novel modulatory pathways via CYP2C modulation and sEH inhibition.
Estrogen Receptor α Gene Variation and the Risk of Stroke
Authors: Shearman Amanda M. , Cooper Jackie A. , Kotwinski Paul J. , Humphries Steve E. , Mendelsohn Michael E. , Housman David E. , Miller George J.
Published: September 2005

Background—

Estrogen receptor α
(
ESR1
) gene variation is associated with a range of important estrogen-dependent characteristics, including responses of lipid profile and atherosclerotic severity to hormone replacement therapy, coronary heart disease risk, and migraine. The roles that reproductive steroids play in cerebrovascular pathophysiology and ischemia are an important area of investigation. Given that there is a significantly higher risk of myocardial infarction among men with the
CC
genotype (
PP
of
PvuII
) of
c.454-397T>C
(rs2234693), we asked whether this genotype is associated with a higher risk of stroke.

Methods—

Relative risk of stroke by genotype was determined in 2709 participants of the Second Northwick Park Heart Study, white males with a mean baseline age 56 years and follow up 10.5 years.

Results—

Compared with participants with the
ESR1 c.454-397CT
or
TT
genotype, those with the
CC
genotype had a relative risk of stroke of 1.92 (95% confidence interval, 1.06 to 3.48,
P
=0.03) after adjustment for age, primary care practice; additional adjustment for body mass index, serum cholesterol and triglyceride levels, hypertension, diabetes, and smoking status. Exclusion of stroke cases with coronary heart disease gave results that were essentially unchanged.

Conclusions—

In this study, subjects with the common
ESR1 c.454-397CC
genotype have a substantial increase in risk of stroke. In another publication, other
ESR1
variation was associated with migraine. We thus hypothesize that estrogen receptor variation may provide a basis for the established relationship among estrogens, migraine, and stroke.
Thyroid Diseases and Cerebrovascular Disease
Authors: Squizzato A. , Gerdes V.E.A. , Brandjes D.P.M. , Büller H.R. , Stam J.
Published: September 2005

Background and Purpose—Acute cerebral ischemia has been described in different diseases of the thyroid gland, and not only as a result of thyrotoxic atrial fibrillation and cardioembolic stroke. The purpose of this review is to summarize the studies on the relationship between thyroid diseases and cerebrovascular diseases, discussing the main findings for overt hyperthyroidism and hypothyroidism, as well as for subclinical thyroid dysfunction.

Summary of Review—In overt hyperthyroidism, cardioembolic stroke is clearly associated to thyrotoxic atrial fibrillation, and in subclinical hyperthyroidism with serum thyroid-stimulating hormone levels <0.1 mU/L, the incidence of atrial fibrillation is increased. Although in vitro and in vivo studies indicate a hypercoagulability state in hyperthyroidism, there is insufficient evidence to prove that this state leads to an increased risk of cardiac emboli. However, the hypothesis that overt hyperthyroidism may cause acute cerebral venous thrombosis is intriguing. Possible associations between hyperthyroidism and Moyamoya or Giant cell arteritis have only been described in case reports. There is enough evidence that overt hypothyroidism is associated with several traditional and newer atherosclerotic risk factors, especially hypertension, hyperlipidemia, and hyperhomocysteinemia. For subclinical hypothyroidism, these associations are less certain. Hypothyroidism has been associated with signs of aortic or coronary atherosclerosis, but no case-control or cohort studies have ever investigated hypothyroidism as a possible risk factor for atherothrombotic stroke.

Conclusions—Hyperthyroidism is associated with atrial fibrillation and cardioembolic stroke. Hypothyroidism is associated with a worse cardiovascular risk factor profile and leads to progression of atherosclerosis. Associations between hyperthyroidism and acute cerebral venous thrombosis, Moyamoya, and Giant cell arteritis have been suggested, but sound evidence is lacking. Additional studies are needed to clarify these issues.
C1q-Deficiency Is Neuroprotective Against Hypoxic-Ischemic Brain Injury in Neonatal Mice
Authors: Ten Vadim S. , Sosunov Sergei A. , Mazer Sean P. , Stark Raymond I. , Caspersen Casper , Sughrue Michael E. , Botto Marina , Connolly E. Sander , Pinsky David J.
Published: September 2005

Background and Purpose—

This study was undertaken to determine whether the initial component of the classical complement (C) activation pathway contributes to hypoxic-ischemic brain injury in neonatal mice.

Methods—

Hypoxia-ischemia (HI) was produced in C1q
−/−
and wild-type (WT) neonatal mice. At 24 hours after HI, neonatal mouse reflex performance and cerebral infarct volume were assessed. Long-term outcomes were measured by water-maze performance and degree of cerebral atrophy at 7 to 8 weeks after HI. Activation of circulating neutrophils, and C1q, C3, and neutrophil deposition in brains were examined.

Results—

C1q
−/−
mice were significantly protected against HI (mean±SE infarct volume in C1q
−/−
mice=17.3±5.5% versus 53.6±6.8% in WT mice;
P
<0.0001) and exhibited significantly less neurofunctional deficit compared with WT mice. Immunostaining revealed significantly greater deposition of C3 (and C1q) as well as granulocytes in the infarcted brains in WT mice compared with C1q
−/−
animals. Activation of circulating leukocytes was significantly decreased in C1q
−/−
mice compared with WT mice, which correlated strongly (
r
=0.7) with cerebral infarct volumes.

Conclusions—

Cerebral deposition of C1q and C3 after hypoxic-ischemic insult is associated with significantly greater neurologic damage in WT mice compared with C1q
−/−
mice, providing strong evidence that the classical C pathway contributes to the hypoxic-ischemic brain injury. Significantly decreased activation of circulating neutrophils associated with diminished local accumulation and attenuation of brain injury in C1q
−/−
mice suggests a potential cellular mechanism by which C1q mediates neurodegeneration in HI.
Genotype at the −174G/C Polymorphism of the Interleukin-6 Gene Is Associated With Common Carotid Artery Intimal-Medial Thickness
Authors: Mayosi Bongani M. , Avery Peter J. , Baker Michelle , Gaukrodger Nicole , Imrie Helen , Green Fiona R. , Farrall Martin , Watkins Hugh , Keavney Bernard
Published: September 2005

Background and Purpose—

Studies in unrelated individuals have produced conflicting findings concerning the putative association between the interleukin-6 (IL-6) −174G/C polymorphism and carotid intimal-medial thickness (IMT). We have used a family-based genetic association design to assess the heritability of carotid IMT and to investigate the hypothesized association of carotid IMT with the IL-6 to −174G/C polymorphism.

Methods—

We studied 854 members of 224 white British families. The heritability of carotid IMT was determined using Multipoint Engine for Rapid Likelihood Inference. Genetic association analyses were carried out using ANOVA and family-based tests of association implemented in Quantitative Transmission Disequilibrium Test. A meta-analysis of previous studies of the association was conducted to place our result in context.

Results—

The heritability of carotid IMT was 24%. Under a recessive model (GG+GC versus CC), there was significant evidence of association between IL-6 to the −174G/C genotype and adjusted log
e
maximal carotid IMT (
F
=5.469;
P
=0.02). Family-based analyses using Quantitative Transmission Disequilibrium Test showed no evidence of population stratification as a cause of the observed association (χ
2
1
=0.469;
P
=0.4934). The CC genotype was associated with a 4.8% increase in maximal carotid IMT and accounted for 0.6% of the observed variation in the trait, which is equivalent to 2.5% of the heritable component. A meta-analysis of the present and 2 previous large studies, which enrolled a total of 2930 subjects, confirmed the recessive effect of the C allele on carotid IMT (
P
=0.0014).

Conclusions—

The genotype at the IL-6 to −174G/C polymorphism is associated with common carotid artery IMT, although the size of the genetic effect is small.
Incidence and Clinical Features of Disease Progression in Adult Moyamoya Disease
Authors: Kuroda Satoshi , Ishikawa Tatsuya , Houkin Kiyohiro , Nanba Rina , Hokari Masaaki , Iwasaki Yoshinobu
Published: September 2005

Background and Purpose—

The progression of occlusive lesions in the major intracranial arteries was believed to be very rare in adult patients with moyamoya disease. The present study aims to clarify the incidence and clinical features of disease progression in adult moyamoya disease.

Methods—

For the past 15 years, 120 adult Japanese patients were diagnosed with moyamoya disease. Of these, 63 patients were enrolled in this historical prospective cohort study on a total of 86 nonoperated hemispheres. All were followed up with a mean period of 73.6 months. MRI and magnetic resonance angiography were repeated every 6 to 12 months, and cerebral angiography was performed when disease progression was suspected on MRI and magnetic resonance angiography.

Results—

Disease progression occurred in 15 of 86 nonoperated hemispheres (17.4% per hemisphere) or in 15 of 63 patients (23.8% per patient) during the follow-up period. Occlusive arterial lesions progressed in both anterior and posterior circulations, in both symptomatic and asymptomatic patients, and in both bilateral and unilateral types. Eight of 15 patients developed ischemic or hemorrhagic events in relation to disease progression. Multivariate analysis revealed that the odds ratio conferred by a male patient was 0.20 (95% CI, 0.04 to 0.97).

Conclusions—

The incidence of disease progression in adult moyamoya disease is much higher than recognized before, and female patients may be at higher risk for it than male patients. Careful follow-up would be essential to prevent additional stroke occurrence in medically treated adult patients with moyamoya disease, even if they are asymptomatic or are diagnosed as having unilateral moyamoya disease.
Fibrinolytic Gene Polymorphism and Ischemic Stroke
Authors: Jood Katarina , Ladenvall Per , Tjärnlund-Wolf Anna , Ladenvall Claes , Andersson Maria , Nilsson Staffan , Blomstrand Christian , Jern Christina
Published: September 2005

Background and Purpose—

The tissue-type plasminogen activator (tPA) −7351C>T and the plasminogen activator inhibitor type 1 (PAI-1) -675 4G >5G polymorphisms influence transcriptional activity. Both variants have been associated with myocardial infarction, with increased risk for the T and 4G allele, respectively. In this study we investigated the possible association between these polymorphisms, the respective plasma protein levels, and ischemic stroke.

Methods—

In the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS), 600 patients with acute ischemic stroke aged 18 to 69 years and 600 matched community controls were recruited. Stroke subtype was determined using Trial of Org 10172 in Acute Treatment criteria.

Results—

There were no associations between individual genetic variants and ischemic stroke. The multivariate-adjusted odds ratio for overall ischemic stroke was 1.11 (95% CI 0.87 to 1.43) for tPA T allele carriers, and 0.84 (95% CI, 0.64 to 1.11) for subjects homozygous for the PAI-1 4G allele. When genotypes were combined, a protective effect for the tPA CC/PAI-1 4G4G genotype combination was observed (odds ratio 0.65, 95% CI 0.43 to 0.98;
P
<0.05). Plasma levels of tPA and PAI-1 antigen at follow-up were independently associated with overall ischemic stroke. tPA-antigen differed by stroke subtype and was highest among those with large-vessel disease and cardioembolic stroke.

Conclusions—

Neither the tPA −7351C>T nor the PAI-1 to 675 4G >5G polymorphism showed significant association with ischemic stroke. For the tPA CC/PAI-1 4G4G genotype combination, a protective effect was observed. Collectively, these results are consistent with a more complex role for tPA and PAI-1 in the brain as compared with the heart.
Long-Term Outcome in the North East Melbourne Stroke Incidence Study
Authors: Paul Seana L. , Sturm Jonathan W. , Dewey Helen M. , Donnan Geoffrey A. , Macdonell Richard A.L. , Thrift Amanda G.
Published: September 2005

Background and Purpose—

Although much is known about the long-term outcome of stroke patients in terms of mortality and disability, there has been little research on the patient-centered outcome of health-related quality of life (HRQoL). There are limited natural history data on HRQoL beyond 2 years after stroke and no data on those factors present at stroke onset that predict HRQoL beyond 2 years after stroke. For these reasons, we aimed to examine these aspects of HRQoL in an unselected population of stroke patients.

Methods—

All cases of first-ever stroke from a prospective community-based stroke incidence study (excluding subarachnoid hemorrhage) were assessed 5 years after stroke. HRQoL was measured with the assessment of quality of life instrument. ANOVA was used to determine baseline predictors of HRQoL.

Results—

In total, 978 cases were recruited, 45% were male, and the mean age (±SD) was 75.5±13.8 years. Five years after stroke, 441 (45.1%) were alive and 356 were assessed (80.7%). Those assessed were more often born in Australia and older in age (both
P
<0.05). Seventy-one survivors (20%) had a very low HRQoL (score ≤0.1). The independent baseline predictors of low HRQoL at 5 years after stroke were increasing age, lower socioeconomic status, and markers of stroke severity.

Conclusion—

At 5 years after stroke, we found that a substantial proportion of survivors were suffering from poor HRQoL. As our population ages, the number of strokes and, thus, stroke survivors with poor HRQoL is likely to increase. Therefore, strategies to improve HRQoL should be vigorously pursued.
Predictors of Depression after Stroke
Authors: Hackett Maree L. , Anderson Craig S.
Published: September 2005

Background and Purpose—

Although depression is common after stroke, there is uncertainty over its etiology and risk factors, which complicates management. Knowledge of the predictors of depression associated with stroke may allow for the better targeting of therapy, both prevention and treatment.

Methods—

We undertook a systematic review of all published, nonexperimental, population-, hospital-, and rehabilitation-based stroke studies (to June 2004) with prospective, consecutive patient recruitment undertaken to identify variables associated with depressive symptoms (or “illness”) after stroke. Assessments were made of the quality of studies including the validity of prognostic models.

Results—

Data were available from 3 population-based studies including 492 patients, 8 hospital-based studies including 15 272 patients, and 9 rehabilitation-based studies including 2170 patients. Physical disability, stroke severity and cognitive impairment were consistently associated with depression. In addition to the common problem of selection bias, major limitations of these studies included variable selection and poor statistical quality and reporting; small sample sizes meant that only a limited range of variables were analyzed in multivariate models.

Conclusions—

There is a paucity of well-designed studies of sufficient size to allow stable multivariate predictive models of depression after stroke to be developed. Other than showing that depression is associated with more severe strokes, current evidence does not allow for ready identification of patients most at risk of developing this important complication of stroke.
Prevalence of Carotid Artery Stenosis in Patients With Coronary Artery Disease in Japanese Population
Authors: Tanimoto Shuzou , Ikari Yuji , Tanabe Kengo , Yachi Sen , Nakajima Hiroyoshi , Nakayama Tomohiro , Hatori Mitsuharu , Nakazawa Gaku , Onuma Yoshinobu , Higashikuni Yasutomi , Yamamoto Hirosada , Tooda Eiichi , Hara Kazuhiro
Published: September 2005

Background and Purpose—

Prevalence of carotid artery stenosis in patients with coronary artery disease (CAD) is unknown in Japanese population.

Methods—

The study populations consisted of 632 consecutive patients who underwent coronary angiography because of suspicion of CAD. All patients underwent carotid ultrasonography to screen carotid artery stenosis before coronary angiography. We defined echographic carotid stenosis as area stenosis of >50% or peak systolic velocity of >200 cm/s.

Results—

Echographic carotid stenosis was observed in 124 patients (19.6%). Coronary angiography revealed 433 patients had CAD. Prevalence of echographic carotid artery stenosis was 14 of 199 (7.0%), 18 of 124 (14.5%), 28 of 131 (21.4%), and 64 of 178 (36.0%) in patients with 0-, 1-, 2-, and 3-vessel CAD, respectively (
P
<0.0001). The prevalence rate with carotid stenosis and CAD was 25.4%. Multivariate stepwise logistic regression analysis showed that age and the extent of CAD were independently related to the presence of carotid stenosis (
P
=0.0002 and <0.0001, respectively).

Conclusions—

Prevalence of carotid stenosis in patients with CAD is high in Japan as well as in Western countries. Screening of carotid artery stenosis is recommended especially in older patients with multivessel CAD.