bluuebunny/crossref_metadata_2025 huggingface dataset:
Large-Scale Comparative Genomic Analyses of Cytoplasmic Membrane Transport Systems in Prokaryotes
Authors: Ren Qinghu , Paulsen Ian T.
Published: June 2007

The recent advancements in genome sequencing make it possible for the comparative analyses of essential cellular processes like transport in organisms across the three domains of life. Membrane transporters play crucial roles in fundamental cellular processes and functions in prokaryotic systems. Between 3 and 16% of open reading frames in prokaryotic genomes were predicted to encode membrane transport proteins, emphasizing the importance of transporters in their lifestyles. Hierarchical clustering of phylogenetic profiles of transporter families, which are derived from the presence or absence of a certain transporter family, showed distinct clustering patterns for obligate intracellular organisms, plant/soil-associated microbes and autotrophs. Obligate intracellular organisms possess the fewest types and number of transporters presumably due to their relatively stable living environment, while plant/soil-associated organisms generally encode the largest variety and number of transporters. A group of autotrophs are clustered together largely due to their absence of transporters for carbohydrate and organic nutrients and the presence of transporters for inorganic nutrients. Inside of each group, organisms are further clustered by their phylogenetic properties. These findings strongly suggest the correlation of transporter profiles to both evolutionary history and the overall physiology and lifestyles of the organisms.
Tripartite ATP-Independent Periplasmic Transporters: Application of a Relational Database for Genome-Wide Analysis of Transporter Gene Frequency and Organization
Authors: Mulligan Christopher , Kelly David J. , Thomas Gavin H.
Published: June 2007

Tripartite ATP-independent periplasmic (TRAP) transporters are a family of extracytoplasmic solute receptor-dependent secondary transporters that are widespread in the prokaryotic world but which have not been extensively studied. Here, we present results of a genome-wide analysis of TRAP sequences and genome organization from application of TRAPDb, a relational database created for the collection, curation and analysis of TRAP sequences. This has revealed a specific enrichment in the number of TRAP transporters in several bacteria which is consistent with increased use of TRAP transporters in saline environments. Additionally, we report a number of new organizations of TRAP transporter genes and proteins which suggest the recruitment of TRAP transporter components for use in other biological contexts.
Contribution of Extracytoplasmic Function Sigma Factors to Transition Metal Homeostasis in Cupriavidus metallidurans Strain CH34
Authors: Grosse Cornelia , Friedrich Susann , Nies Dietrich H.
Published: June 2007

Cupriavidus metallidurans strain CH34 is a highly metal-resistant bacterium that contains 11 sigma factors of the extracytoplasmic function (ECF) protein family, which can be subgrouped into the ECF:FecI 1, ECF:FecI 2, ECF:RpoE and ‘(ECF)’ clusters. To analyze the contribution of these 11 sigma factors to metal resistance, upregulation of the respective genes was measured by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). As determined by RT-PCR, the ECF sigma factor genes were part of two- to tetra-cistronic operons, each containing genes for the sigma factor plus one or two antisigma factors. The three sigma factors RpoJ, RpoK and RpoI (ECF:FecI 1 cluster) were upregulated by Cu(II) and Ni(II), and under conditions of iron depletion. The other 8 ECF sigma factor genes were not induced by iron depletion. Strong upregulation of rpoJ and rpoK under iron depletion in a ΔrpoI mutant strain and close vicinity of rpoI to genes involved in iron siderophore metabolism marked RpoI as the primary ECF sigma factor for siderophore-mediated iron uptake. Genes for RpoO, RpoL and RpoM (ECF:FecI 2 cluster) were not upregulated by transition metal cations and influenced metal resistance only weakly. Concerning the two ‘(ECF)’ group proteins, rpoQ was strongly upregulated by Cu(II) and deletion of rpoR led to a small decrease in copper resistance. Of the three ECF:RpoE-encoding genes, rpoP was not transcribed under the conditions tested, cnrH was upregulated by Ni(II) and essential for nickel resistance as known before. RpoE was required for full metal resistance of C. metallidurans. None of these 11 sigma factors was essential for metal resistance mediated by the cobalt, zinc and cadmium resistance determinant czc, or for its expression. However, RpoI was essential for siderophore production in C. metallidurans, and, in addition to the known role of CnrH in nickel resistance, RpoE, RpoI, RpoJ, RpoK and maybe also RpoQ are required for the outstanding transition metal resistance of this bacterium.
In vitro Interconversion of the Soluble and Membrane- Integrated Forms of the Escherichia coli Glucose Enzyme II of the Phosphoenolpyruvate-Dependent Sugar-Transporting Phosphotransferase System
Authors: Aboulwafa Mohammad , Saier Jr. Milton H.
Published: June 2007

In previous publications, we have shown that integral membrane sugar permeases of the bacterial phosphotransferase system can exist in a ‘soluble’ (probably micellar) monomeric form (SII) as well as a membrane-integrated dimeric form (MII). We here show that the two forms of the his-tagged glucose permease of Escherichia coli can be interconverted in vitro. Conversion of MII to SII is promoted by (1) low protein concentration, (2) detergent, (3) high pH, and (4) phospholipase A2 treatment. Conversion of SII to MII is promoted by: (1) high protein concentration, (2) adherence to and elution from an Ni2+ column, (3) neutral pH, and (4) incorporation into phospholipid liposomes.
The Phosphoenolpyruvate:Sugar Phosphotransferase System and Biofilms in Gram-Positive Bacteria
Authors: Sutrina Sarah L. , McGeary Tamisha , Bourne Carol-Ann
Published: June 2007

This review will examine the connection between the bacterial phosphoenolpyruvate:sugar phosphotransferase system and biofilms. We will consider both the primary role of the phosphoenolpyruvate:sugar phosphotransferase system in sugar uptake by biofilm cells and its possible role in regulatory processes in cells growing as biofilms, and in establishment and maintenance of these biofilms.
Classification of Ph-Negative Chronic Myeloproliferative Disorders – Morphology as the Yardstick of Classification
Authors: Kvasnicka Hans Michael , Thiele Jürgen
Published: June 2007

Objective: Histopathology of bone marrow (BM) biopsies plays a crucial role in the interdisciplinary approach to diagnosis and classification of Ph-negative chronic myeloproliferative disorders. Based on careful clinicopathologic studies, BM features are critical determinants that help to predict overall prognosis, to detect complications such as progression to myelofibrosis and blast crisis, and to assess therapy-related changes. Methods and Results: A systematic evaluation of BM histopathology allows an objective identification of cases of (true) essential thrombocythemia and their separation from early prefibrotic stages of chronic idiopathic myelofibrosis. By follow-up examinations that include BM biopsies, the progression of the disease process is unveiled, which is especially important for patients with initial polycythemia vera and prefibrotic chronic idiopathic myelofibrosis that may require a different therapeutic approach than the full-blown stages. Conclusion: BM biopsy should be considered as major diagnostic tool for evaluation and follow-up of patients enrolled in prospective studies.
Diagnosis and Classification of Malignant Lymphoma and Related Entities in the Bone Marrow Trephine Biopsy
Authors: Fend Falko , Kremer Markus
Published: June 2007

The trephine bone marrow (BM) biopsy is an important diagnostic tool in patients with malignant lymphoma. BM examination can serve to establish or confirm a primary diagnosis of lymphoma or to determine the extent of disease dissemination for staging purposes. BM histology renders information which cannot be gained equally from aspirate material, such as spacial distribution and extent of infiltrates, BM cellularity and fibrosis. Furthermore, cytology including flow cytometric immunophenotyping can give false-negative results in BM involvement by lymphoma due to intralesional fibrosis. In addition to morphological examination, the availability of a broad panel of antibodies suitable for paraffin-embedded tissues, in conjunction with less damaging decalcification procedures, nowadays enables us to perform complete immunophenotyping on BM trephines and allows for classification of lymphoma infiltrates according to established algorithms. Molecular determination of clonality and interphase fluorescent in situ hybridization can be employed selectively to resolve difficult cases. This review describes important diagnostic features of malignant lymphoma in the BM, relevant differential diagnoses, and the proper use of ancillary techniques.
Outbreak Report of Airborne Caterpillar Dermatitis in a Kindergarten
Authors: Gottschling Sven , Meyer Sascha , Dill-Mueller Dorothee , Wurm Donald , Gortner Ludwig
Published: June 2007

Background: The oak processionary caterpillar is found in several European countries. The larva of Thaumetopoea processionea Lepidoptera from the third to sixth larval instar develops poisonous hair (setae), filled with an urticating toxin that could lead to serious dermatitis, conjunctivitis and pulmonary problems (summarized as lepidopterism) on contact. Objectives: To determine the incidence of caterpillar dermatitis in a kindergarten population with three infested oak trees located in its enclosure. Methods: We made a survey by the use of a questionnaire that was handed out to all parents with children regularly visiting that kindergarten. Results: Twenty-four out of 47 (51%) questionnaires were returned and 10/24 (42%) children showing symptoms of lepidopterism were reported: 8/10 (80%) dermatitis, 5/10 (50%) pruritus, 5/10 (50%) respiratory distress, 4/10 (40%) malaise and/or fever and 1/10 (10%) conjunctivitis. Seven out of 10 visited a physician but the correct diagnosis was not posed in any case. Four out of 7 received medication (topical and/or systemic antihistaminics and/or steroids). Conclusions: Lepidopterism, an airborne disease caused by the setae of the processionary caterpillar, is a growing public health problem because of the increasing numbers of outbreaks, and it is still underestimated. Children seem to suffer more often from general symptoms and airway affection than adults.
Imiquimod 5% Cream for the Prevention of Recurrence after Excision of Presternal Keloids
Authors: Malhotra Amit Kumar , Gupta Somesh , Khaitan Binod K. , Sharma Vinod K.
Published: June 2007

Imiquimod 5% cream has been found to be effective and safe in preventing recurrence of keloids on earlobes after excision. We evaluated the efficacy and safety of imiquimod 5% cream in preventing the recurrence of presternal keloids after excision (3 keloids in 2 patients). After excision with radiofrequency, imiquimod 5% cream was applied once daily at bedtime for 8 weeks, and the defect was left to heal by secondary intention. In all the treated keloids, the defect healed in 6–8 weeks, and no recurrence was seen while on imiquimod application; however, all keloids completely recurred within 4 weeks of stopping imiquimod. Side effects were mild and acceptable in the form of burning and pain. Imiquimod did exert an antifibrotic action but it was short-lived.
Dermoscopy of Microvenular Hemangioma: Report of a Case
Authors: Scalvenzi Massimiliano , De Natale Flora , Francia Maria Grazia , Balato Anna
Published: June 2007

We describe a 31-year-old woman with an asymptomatic solitary red plaque on the back which measured 2 × 1 cm. The patient reported that it had been growing for a few months. Upon dermoscopic examination, multiple well-demarcated red globules were seen. At the periphery a fine pigment network was present. The lesion was excised and examined histopathologically. The specimen showed proliferation of irregular branching venules with inconspicuous lumina. The tumor cells lacked cellular atypia. Microvenular hemangioma is a rare, slowly growing, benign vascular tumor. It usually presents on the trunk or the extremities of young to middle-aged adults. Microvenular hemangioma is a benign vascular tumor with distinct dermoscopic and histopathological features which enable it to be distinguished from other vascular neoplasms.
Glucose Regulation in Preterm Newborn Infants
Authors: Mitanchez Delphine
Published: June 2007

After birth, continuous transplacental transfer of glucose is interrupted. Neonates have to provide brain and vital organs with sufficient glucose. In term newborn infants, this is accomplished through well-coordinated hormonal and metabolic adaptive changes. During the first week of life, preterm infants are at high risk of abnormal glucose homeostasis. They are at risk of hypoglycemia due to limited glycogen and fat stores that should have occurred in the third trimester. Continuous glucose infusion is always required soon after birth to maintain the glucose level. However, under such conditions, many preterm infants develop hyperglycemia. Defective islet β-cell processing of proinsulin is likely related to hyperglycemia. There is also evidence that preterm infants are partially resistant to insulin. By contrast with adults, hepatic glucose production is not suppressed during parenteral glucose infusion. Exogenous insulin infusion partially reduces endogenous glucose production in preterm newborn infants. This treatment is efficient and safe when used with caution. More research is needed to understand the specificity of glucose homeostasis in preterm infants and to evaluate the long-term consequences of metabolic and nutritional support during early life.
Intervention Study to Improve Quality of Life and Health Problems of Community-Living Elderly Women in Japan by Shoe Fitting and Custom-Made Insoles
Authors: Kusumoto Ayano , Suzuki Takao , Yoshida Hideyo , Kwon Jinhee
Published: June 2007

Background: To maintain and improve foot environment that forms the basis of everyday life of the elderly is an important issue not only from the viewpoint to provide support for functional capacity, but also to maintain the quality of life (QOL) of the elderly. Objective: To determine the effects of shoe-fitting guidance and wearing shoes with custom-made insoles (CMI) on improving the health-related QOL of community-living elderly women. Methods: Seventy-nine healthy women who lived in an urban community aged 65–92 years were allocated randomly to a control group (n = 40; mean age ± SD 75.0 ± 5.1 years) or an intervention group (n = 39; mean age ± SD 75.5 ± 6.0 years). The intervention group was given detail guidance on shoe fitting and asked to wear shoes with CMI for 1 month. The control group had a 30-min lecture on better ways of choosing shoes. The QOL was assessed using the Medical Outcomes Study Short Form 36 (SF-36). Results: No significant differences in baseline measurements were observed between the two groups in all 10 scores of the SF-36 (8 domains and 2 summary scores). After intervention, the two groups differed significantly in three domains: mental health, bodily pain, and general health (p < 0.05). In comparing the mean baseline and postintervention SF-36 scores, the control group showed no significant differences in all 10 scores. On the other hand, the intervention group improved in five domains and two summary scores, i.e., vitality and mental component summary (p < 0.05), role physical, general health perceptions, role emotional and physical component summary (p < 0.01), and mental health (p = 0.0003). The intervention was markedly effective not only in the physical but also in the mental aspect. Conclusion: Wearing shoes with CMI adjusted to individual feet significantly improves the health-related QOL, including both physical and mental aspects in community-living elderly women.
No Associations between Prolactin Concentrations and Response to Erythropoiesis-Stimulating Agents in Hemodialysis Patients
Authors: Riegersperger Markus , van Houte Michael , Födinger Manuela , Wojcik Jadwiga , Hörl Walter H. , Winkelmayer Wolfgang C. , Sunder-Plassmann Gere
Published: June 2007

Background: The effect of serum prolactin levels on the response to erythropoiesis-stimulating agents (ESA) in patients on chronic hemodialysis is unknown. Methods: We included 111 stable hemodialysis patients in this study and examined the association of serum prolactin concentrations with the response to ESA. Accordingly we implemented an ESA index as a measure of therapeutic efficacy. The two outcomes of this cohort study were the association of prolactin concentrations with response to ESA, both at baseline (cross-sectional component) and after 1-year of follow-up (prospective component), and the presence of macroprolactin. Results: Two male patients, but none of the female patients, had serum prolactin concentrations within the reference range. Following precipitation with polyethylene glycol (PEG), 17 males (25.4%) and 9 females (20.6%) had serum prolactin concentrations within the reference range. Females had somewhat higher levels than males: 39.8 (IQR 32.3–64.5) versus 27.8 (IQR 23.4–47.8) ng/ml (p = 0.003). The ratio of prolactinPEG/prolactinNative was greater than 0.60 in 103 patients (92.8%), thus excluding significant amounts of macroprolactin. From uni- and multivariate analyses we did not find associations of serum prolactin concentrations with a response to ESA either at baseline or at follow-up. Conclusions: From this prospective study we provide evidence that elevated serum prolactin levels are not related to the presence of macroprolactin in chronic hemodialysis patients. Furthermore, serum prolactin concentrations are not associated with the response to erythropoietic therapy in these individuals.
Diffusion Tensor Anisotropy in Adolescents and Adults
Authors: Schneiderman Jason S. , Buchsbaum Monte S. , Haznedar M. Mehmet. , Hazlett Erin A. , Brickman Adam M. , Shihabuddin Lina , Brand Jesse G. , Torosjan Yuliya , Newmark Randall E. , Tang Cheuk , Aronowitz Jonathan , Paul-Odouard Reshmi , Byne William , Hof Patrick R.
Published: June 2007

We acquired diffusion tensor images on 33 normal adults aged 22–64 and 15 adolescents aged 14–21. We assessed relative anisotropy in stereotaxically located regions of interest in the internal capsule, corpus callosum, anterior thalamic radiations, frontal anterior fasciculus, fronto-occipital fasciculus, temporal lobe white matter, cingulum bundle, frontal inferior longitudinal fasciculus, frontal superior longitudinal fasciculus, and optic radiations. All of these structures except the optic radiations, corpus callosum, and frontal inferior longitudinal fasciculus exhibited differences in anisotropy between adolescents and adults. Areas with anisotropy increasing with age included the anterior limb of the internal capsule, superior levels of the frontal superior longitudinal fasciculus and the inferior portion of the temporal white matter. Areas with anisotropy decreasing with age included the posterior limb of the internal capsule, anterior thalamic radiations, fronto-occipital fasciculus, anterior portion of the frontal anterior fasciculus, inferior portion of the frontal superior longitudinal fasciculus, cingulum bundle and superior portion of the temporal axis. Sex differences were found in the majority of areas but were most marked in the cingulum bundle and internal capsule. These results suggest continuing white matter development between adolescence and adulthood.
Properties of Ceramides and Their Impact on the Stratum Corneum Structure: A Review
Authors: Wartewig S. , Neubert R.H.H.
Published: June 2007

The lipid matrix of the stratum corneum (SC) is the major diffusion-rate-limiting pathway by which most drugs intracellularly pass the SC. The major lipid classes extracted from the SC are ceramides, cholesterol and free fatty acids. Ceramides that comprise nine subclasses play a crucial role in maintaining the barrier function of the skin. A profound knowledge of the physical properties of ceramides is essential for a deeper understanding of the impact of each ceramide species on the barrier function. The review summarizes the thermotropic and/or lyotropic behaviour of sphingosine-type ceramides (CER AS, CER NS) and phytosphingosine-type ceramides (CER AP, CER NP) revealed by differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy and Fourier transform Raman spectroscopy in past decades. Polymorphism is a characteristic feature of ceramides. At physiological temperatures, all crystalline phases of ceramides exhibit lamellar structures with highly ordered hydrocarbon chains. The differential behaviour of the head groups of ceramides may be an important determinant for the skin barrier function.
Functional Assessment of a Skin Care System in Patients on Chemotherapy
Authors: Fluhr J.W. , Miteva M. , Primavera G. , Ziemer M. , Elsner P. , Berardesca E.
Published: June 2007

Background/Purpose: Cancer patients undergoing chemotherapy frequently experience skin problems such as xerosis. The aim of this study was to verify whether a concomitant treatment with an acidic washing and an acidic emollient (both pH 5.5) can significantly improve the quality of the skin in such patients. Methods: 30 adult patients on chemotherapy experiencing dry and sensitive skin were included in a controlled, monocentric, 3-week treatment trial. One forearm served as a test site, the other one remained untreated. Noninvasive biophysical measurements were performed at baseline, on days 7, 14 and 21, along with clinical evaluation of the skin symptoms. Results: After a 3-week treatment, a significant increase in stratum corneum hydration was recorded in the treated site (p < 0.001). Reduced transepidermal water loss values, consistent with a restored barrier function, were obtained (p < 0.001). Casual sebum levels as measured by sebumetry showed a significant increase (p < 0.03). All skin symptoms investigated revealed a considerable improvement over 3 weeks. Conclusion: Controlled and regular use of a skin care system, especially an acidic one, improved skin physiology in patients undergoing chemotherapy.
Endothelial Signaling by Ig-Like Cell Adhesion Molecules
Authors: van Buul Jaap D. , Kanters Edwin , Hordijk Peter L.
Published: June 2007

The migration of leukocytes across the endothelial lining of the vascular wall requires a complicated series of adhesion and signaling events. Endothelial Ig-like cell adhesion molecules (IgCAMs) such as intercellular adhesion molecule-1 play an important role, not only as ligands for leukocyte integrins, but also as signaling initiators. Clustering these IgCAMs triggers a wide range of events in the endothelial cells’ interior, of which activation of Rho-like GTPases, induction of cytoskeletal changes, and the transient modulation of cell-cell contact are key events. This review discusses recent insights into this IgCAM-driven endothelial signaling and its consequences for leukocyte transendothelial migration.
T-Cell–Derived Interferon-γ Contributes to Arteriolar Dysfunction During Acute Hypercholesterolemia
Authors: Stokes Karen Y. , Gurwara Shelly , Granger D. Neil
Published: June 2007

Objectives—

T-lymphocytes and interferon-γ (IFN-γ) contribute to leukocyte recruitment in postcapillary venules during hypercholesterolemia. Our objectives were to determine whether: (1) T-lymphocytes are the source of this IFN-γ, and (2) whether T-cell–derived IFN-γ also mediates the accompanying arteriolar dysfunction and platelet adhesion.

Methods and Results—

Intravital videomicroscopy was used to quantify arteriolar responses to acetylcholine, and leukocyte and platelet adhesion in postcapillary venules of wild-type (WT), immunodeficient (SCID), and IFN-γ
−/−
mice on a normal (ND) or high-cholesterol (HC) diet. Acetylcholine-induced arteriolar dilation was impaired in WT-HC, compared with WT-ND. This endothelial dysfunction was absent in SCID-HC or IFN-γ
−/−
-HC mice. Vasodilation was impaired by transfer of WT, but not IFN-γ
−/−
, T-cells to these immunodeficient mice. WT-HC mice exhibited elevated leukocyte and platelet adhesion in venules, versus WT-ND. This blood cell recruitment was attenuated to ND levels in SCID-HC and IFN-γ
−/−
-HC mice, but restored to WT-HC levels by transfer of WT, but not IFN-γ
−/−
, T-lymphocytes.

Conclusions—

These data reveal a novel role of T-lymphocyte–derived IFN-γ in the development of endothelial dysfunction in arterioles during hypercholesterolemia and extend our previous observations that IFN-γ mediates both inflammatory and thrombogenic responses to hypercholesterolemia in postcapillary venules.
Vascular Endothelial Cell–Specific NF-κB Suppression Attenuates Hypertension-Induced Renal Damage
Authors: Henke Norbert , Schmidt-Ullrich Ruth , Dechend Ralf , Park Joon-Keun , Qadri Fatimunnisa , Wellner Maren , Obst Michael , Gross Volkmar , Dietz Rainer , Luft Friedrich C. , Scheidereit Claus , Muller Dominik N.
Published: June 2007

Nuclear factor kappa B (NF-κB) participates in hypertension-induced vascular and target-organ damage. We tested whether or not endothelial cell–specific NF-κB suppression would be ameliorative. We generated Cre/lox transgenic mice with endothelial cell–restricted NF-κB super-repressor IκBαΔN (Tie-1-ΔN mice) overexpression. We confirmed cell-specific IκBαΔN expression and reduced NF-κB activity after TNF-α stimulation in primary endothelial cell culture. To induce hypertension with target-organ damage, we fed mice a high-salt diet and N(omega)-nitro-
l
-arginine-methyl-ester (L-NAME) and infused angiotensin (Ang) II. This treatment caused a 40-mm Hg blood pressure increase in both Tie-1-ΔN and control mice. In contrast to control mice, Tie-1-ΔN mice developed a milder renal injury, reduced inflammation, and less albuminuria. RT-PCR showed significantly reduced expression of the NF-κB targets VCAM-1 and ICAM-1, compared with control mice. Thus, the data demonstrate a causal link between endothelial NF-κB activation and hypertension-induced renal damage. We conclude that in vivo NF-κB suppression in endothelial cells stops a signaling cascade leading to reduced hypertension-induced renal damage despite high blood pressure.
Central Role of TRPM4 Channels in Cerebral Blood Flow Regulation
Authors: Reading Stacey A. , Brayden Joseph E.
Published: June 2007

Background and Purpose—

The transient receptor potential channel TRPM4 is critically linked to the myogenic constrictor response of cerebral arteries that occurs when intravascular pressure increases. This myogenic behavior is thought to be fundamentally involved in the mechanisms of blood flow autoregulation. In this study, we tested the hypothesis that TRPM4 channels in cerebrovascular myocytes contribute to cerebral blood flow autoregulation in vivo.

Methods—

In vivo suppression of cerebrovascular TRPM4 expression was achieved by infusing antisense oligodeoxynucleotides into the cerebral spinal fluid of 400- to 550-g Sprague-Dawley rats at 80 μg · day
−1
for 7 days using an osmotic pump that discharged into the lateral cerebral ventricle. Absolute cerebral blood flow measurements were obtained over a range of mean arterial pressures using fluorescent microsphere methods.

Results—

Oligonucleotides infused into the cerebrospinal fluid were detected in the smooth muscle cells of pial arteries. Semi-quantitative RT-PCR indicated that the message for TRPM4 was decreased in the cerebral arteries of antisense-treated rats. Myogenic constriction was decreased by 70% to 85% in cerebral arteries isolated from TRPM4 antisense- compared with control sense-treated rats. Cerebral blood flow was significantly greater in TRPM4 antisense- versus sense-treated rats at resting and elevated mean arterial pressures, indicating that autoregulatory vasoconstrictor activity was compromised in TRPM4 antisense-treated animals.

Conclusions—

In vivo suppression of TRPM4 decreases cerebral artery myogenic constrictions and impairs autoregulation, thus implicating TRPM4 channels and myogenic constriction as major contributors to cerebral blood flow regulation in the living animal.
Frequent Atrial Premature Beats Predict Paroxysmal Atrial Fibrillation in Stroke Patients
Authors: Wallmann Dieter , Tüller David , Wustmann Kerstin , Meier Pascal , Isenegger Jörg , Arnold Marcel , Mattle Heinrich P. , Delacrétaz Etienne
Published: June 2007

Background and Purpose—

For patients having suffered ischemic stroke, the current diagnostic strategies often fail to detect atrial fibrillation as a potential cause of embolic events. The aim of the study was to identify paroxysmal atrial fibrillation in stroke patients. We hypothesized that patients with frequent atrial premature beats (APBs) recorded in 24-hour ECG will show more often atrial fibrillation when followed by repeated long-term ECG recordings than patients without or infrequent APBs.

Methods—

127 patients with acute ischemic stroke and without known AF were enrolled in a prospective study to detect paroxysmal AF. Patients were stratified according to the number of APBs recorded in a 24-hour ECG (≥70 APBs versus <70 APBs). Subsequently, they all underwent serial 7-day event-recorder monitoring at 0, 3, and 6 months.

Results—

Serial extended ECG monitoring identified AF in 26% of patients with frequent APBs but only in 6.5% when APBs were infrequent (
P
=0.0021). A multivariate analysis showed that the presence of frequent APBs in the initial 24-hour ECG was the only independent predictor of paroxysmal AF during follow-up (odds ratio 6.6, 95% confidence intervals 1.6 to 28.2,
P
=0.01).

Conclusions—

In patients with acute ischemic stroke, frequent APBs (≥70/24 hours) are a marker for individuals who are at greater risk to develop or have paroxysmal AF. For such patients, we propose a diagnostic workup with repeated prolonged ECG monitoring to diagnose paroxysmal AF.
Chronic Mesenteric Ischemia Resulting from Isolated Lesions of the Superior Mesenteric Artery
Authors: Carrick Ryan P. , Borge Marc A. , Labropolous Nicos , Rodriguez Heron
Published: June 2007

Atherosclerosis is a common cause of chronic mesenteric ischemia, generally affecting 2 or more arterial branches supplying the gut. The authors present a case in which symptomatic mesenteric ischemia was the result of 2 tandem atherosclerotic lesions in the superior mesenteric artery. Both the celiac axis and inferior mesenteric arteries were fully patent. The patient experienced complete relief of symptoms after percutaneous deployment of an intravascular stent across the proximal arterial narrowing. The case also documents the existence of an atheroma in a distal mesenteric artery.
Right Ventricular Volume and Mass Determined by Cine Magnetic Resonance Imaging in HIV Patients with Possible Right Ventricular Dysfunction
Authors: Kjær Andreas , Lebech Anne-Mette , Gerstoft Jan , Hesse Birger , Petersen Claus Leth
Published: June 2007

Impaired right ventricular (RV) function has been reported to occur in patients with HIV when studied by echocardiography. However, for accurate evaluation of RV function and morphology, first-pass radionuclide ventriculography (RNV) and cine magnetic resonance imaging (cine-MRI) are methods of choice. Studies of RV involvement in patients with HIV are of interest since pulmonary hypertension is a known serious complication of HIV recognized with increasing frequency. The aim of the present study was to characterize cardiac function and geometry in patients with HIV and reduced right ventricular ejection fraction (RVEF). To do so, we screened patients with RNV and performed an additional cine-MRI in those with reduced RVEF determined by RNV. Ninety patients with HIV were included. To evaluate the MRI measures exactly we included 18 age- and gender-matched healthy volunteers to establish reference values. RNV showed in 13 of the 90 patients a reduced RVEF with a standard cutoff value for RVEF of 0.50. Six of these agreed to have an additional MRI investigation performed. These 6 patients with HIV had an RVEF measured by RNV between 0.41-0.49. Measured by MRI the range of RVEF was 0.47-0.55 with 3 below the lower 95% reference limit according to the control group (lower reference limit: 0.49). None of the 6 patients with HIV had dilated right ventricle and only 1 had a marginally increased right ventricular mass index of 43 g/m2(reference: <41 g/m2). With use of MRI, a few patients with HIV may have a marginally reduced RVEF but normal RV dimensions and mass. Thus, RV dysfunction does not seem to constitute a major clinical problem in this antivirally treated HIV population.
Incomplete Ventricular Septal Rupture Following Blunt Chest Trauma
Authors: Kashima Yuichiro , Kinoshita Osamu , Ikeda Uichi , Yajima Noriyuki , Imamura Hiroshi , Urayama Hiroaki , Iwashita Tomomi , Sekiguchi Yukio , Akita Shingo , Wada Noriko , Okamoto Kazufumi
Published: June 2007

This report describes a case of traumatic incomplete rupture of the ventricular septum, a rare complication caused by blunt chest trauma. Although a serial ECG progressed its course similar to acute anteroseptal myocardial infarction in this case, there was little clinical clue of septal tear. The diagnosis was established by transthoracic echocardiography. The authors chose a conservative line of management rather than surgical repair for incomplete septal rupture because of the patent’s stable clinical course and hemodynamic status. A sequence of echocardiography during a 32-day stay in the hospital showed no change in the extent of incomplete septal rupture, septal structure, systolic function, and shape of left ventricle and also obtained no evidence of shunting through the rupture. In conclusion, echocardiography is a useful investigation to make a diagnosis as well as for follow-up in case of incomplete ventricular septal rupture. A close follow-up of incomplete septal rupture with serial echocardiography should be performed, because several cases of delayed ventricular septal rupture following blunt chest trauma have been reported.
Rupture of a Nonaneurysmal Aorta Secondary to Staphylococcus Aortitis
Authors: Stephens Christopher T. , Pounds Lori L. , Killewich Lois A.
Published: June 2007

Infectious aortitis has become increasingly uncommon and, when diagnosed, typically occurs in an immunocompromised elderly male with a history of Staphylococcus or Salmonella infection and underlying atheromatous cardiovascular disease. The authors report a case of a 74-year-old man with aortitis complicated by rupture secondary to Staphylococcus aureus infection. The patient presented with worsening abdominal pain and fever after being discharged from the emergency room 2 weeks before with back pain and leukocytosis diagnosed as urinary tract infection and bronchitis. Computed tomography (CT) imaging of the retroperitoneum on the first visit appeared normal. Repeat CT scan on the subsequent visit revealed a contained rupture of a nonaneurysmal aorta at the level of the diaphragm. The patient was taken to the operating room emergently for repair. An infected periaortic hematoma and a 1 cm perforation in the posterior aorta were found. The aorta was excised and the area debrided. Revascularization was performed using a 22 mm extruded polytetrafluoroethylene (ePTFE) interposition graft placed in situ. This case demonstrates that a high index of suspicion is required in diagnosing infectious aortitis and that the diagnosis may be delayed in many cases. Additionally, it may not be uncommon for the infected aorta to rupture without prior aneurysm formation.
Raised Plasma Fibrinogen Concentration in Patients With Abdominal Aortic Aneurysm
Authors: Al-Barjas Hamad S. , Ariëns Robert , Grant Peter , Scott Julian A.
Published: June 2007

A feature associated with abdominal aortic aneurysms (AAA) is the presence of intraluminal thrombi (ILT). Elevated plasma fibrinogen concentrations predict a greater risk of thrombosis. Therefore, the authors assessed the relationship between fibrinogen levels, AAA size, and ILT. An age- and sex-matched case-control study was conducted. Demographic data and plasma samples were obtained from 110 patients with AAA and 110 controls. All subjects had an abdominal ultrasound scan to determine the size of the aneurysm and the percentage of the ILT occupying the lumen. Plasma fibrinogen concentrations were measured by the Clauss method. Fibrinogen concentrations were significantly higher in patients with AAA than in controls (median: 2.89 vs 2.53 g/L; p<0.01). Patients with AAA who were current smokers had a larger median AAA size (4.50 vs 4.30 cm; p<0.04) and greater percentage of the ILT (40% vs 30%) than those who did not smoke. Fibrinogen was positively correlated with AAA size (r =0.323; p<0.01) and the percentage of ILT occupying the lumen (r =0.358; p<0.05). Fibrinogen levels were higher in the AAA group. The authors also demonstrated positive correlations between the AAA size, ILT, and fibrinogen concentration. Smoking was associated with larger aneurysms and ILT. Fibrinogen may be a useful marker to monitor the progression of AAA.
An Electrocardiographic Algorithm for Determining the Location of Pacemaker Electrode in Patients With Right Bundle Branch Block Configuration During Permanent Ventricular Pacing
Authors: Okmen Ertan , Erdinler Izzet , Oguz Enis , Akyol Ahmet , Turek Onur , Cam Nese , Ulufer Tanju
Published: June 2007

The expected morphology of right ventricular pacing is a left bundle branch block (LBBB) pattern. However, right bundle branch block (RBBB) can also be seen during permanent right ventricular pacing. The aim of this study was to develop an electrocardiographic algorithm to differentiate this benign condition from septal and free wall perforation with subsequent left ventricular pacing. Three hundred consecutive patients who had permanent ventricular or dual-chamber pacemaker implantation between 1999 and 2000 were screened and 25 patients (8.3%) who exhibited RBBB configuration were included in the study. Echocardiograms and chest radiographs were evaluated in order to identify the pacing lead location in this group. The authors formed a study group with their own 25 patients and 22 cases of RBBB with permanent pacemaker from previous publications (total 47 patients). Frontal axis, QRS morphology in lead V1, and the precordial transition point, which is defined as the precordial lead where R wave amplitude is equal to S wave amplitude, were examined. Placement of precordial leads V1 and V2 1 interspace lower than the standard location (Klein maneuver) eliminated the RBBB pattern in 12 patients. RBBB pattern with “true right ventricular pacing” was detected in 24 of the 25 patients, and in 11 of the 22 patients reported in the literature (total 35 patients). Right ventricular pacing was correctly identified in 34 of 35 patients with use of criteria including left superior axis deviation, RS or qR morphology in lead V1, and precor-dial transition at lead V3 with a high sensitivity and specificity. A simple surface electrocardiogram can accurately predict the lead location in patients having RBBB morphology with right ventricular pacing.
Differences in Vascular Reactivity Between Men and Women
Authors: Schank Bob J. , Acree Luke S. , Longfors Jessica , Gardner Andrew W.
Published: June 2007

The purpose of this study was to compare the gender and age-related differences in vascular reactivity in healthy men and women across a wide age range. Fifty-seven men and 61 women between 20 and 89 years of age, free of cardiovascular disease and risk factors, were categorized into younger (20-39 years), middle-aged (40-59 years), and older (60-89 years) age groups. Subjects were characterized on body weight and height, body mass index (BMI), and calf blood flow under resting, postocclusive reactive hyperemic (PORH), and maximal hyperemic conditions in the lower extremity with use of venous occlusion mercury strain-gauge plethysmography. Similar baseline characteristics were observed among age groups, whereas men had greater body weight (p<0.05), higher BMI values (p<0.05), and a trend toward higher ankle-brachial index (ABI) values (p=0.054) than women. While calf blood flow measurements were similar for men and women at rest and at maximal hyperemic conditions, women had a greater percentage change in calf blood flow from rest to PORH than men (p=0.046). After adjusting for body weight, BMI, and ABI, the percentage change in calf blood flow from rest to PORH was no longer significantly higher in the women (p>0.05). Furthermore, the percentage change in calf blood flow from rest to PORH was negatively related to body weight ( r = -0.30, p<0.01) and to BMI ( r = -0.26, p<0.01) in the men and women. No differences (p>0.05) in the calf blood flow measures were observed among the age groups. In a healthy cohort free of cardiovascular disease, increased BMI accounted for poorer vascular reactivity in men compared to women regardless of age.
Arterial Stiffness: Determinants and Relationship to the Metabolic Syndrome
Authors: Achimastos Apostolos D. , Efstathiou Stamatis P. , Christoforatos Theodore , Panagiotou Themistoklis N. , Stergiou George S. , Mountokalakis Theodore D.
Published: June 2007

This study aimed to investigate independent determinants of arterial stiffness and evaluate the association of arterial stiffness with the presence of metabolic syndrome (MS). Demographic characteristics, hemodynamic parameters, and cardiovascular (CV) risk factors were assessed in Greek food industry employees with no history of diabetes or CV disease in order to isolate multiple correlates of arterial stiffness as assessed by pulse wave velocity (PWV). Subsequently, logistic regression analysis was performed using as end point the presence of MS, defined according to the National Cholesterol Education Program. Data from 424 participants (mean age 45.3 ∓15.5 years, 298 [70.3%] males, average PWV 8.5 ∓3.6 m/s) were analyzed. PWV was higher in men (8.8 ∓3.1 m/s) compared to women (7.7 ∓2.9 m/s, p<0.01). Age, systolic blood pressure, and heart rate were isolated as multivariate determinants of PWV (adjusted R2 0.511 [p<0.0001] in men and 0.538 [p<0.0001] in women). The overall prevalence of the MS was 14.6%, being similar in both genders. Four variables were shown to be independent predictors of the presence of MS: waist circumference >102 cm (men)/88 cm (women) (OR 8.6, [95% CI 2.8, 20.6], p<0.001), insulin resistance (homeostasis model assessment >4) (6.3, [2.1, 17.6], p<0.001), total cholesterol >240 mg/dL (5.5, [1.7, 12.4], p<0.01), PWV >9 m/s (4.1, [1.5, 9.9], p<0.01). High PWV, which was found to be mostly determined by advanced age, elevated systolic BP, and accelerated heart rate, appeared to exhibit a strong independent association with the presence of MS together with adiposity and insulin resistance. This index should be considered as a useful marker for CV risk stratification.
Intermediate Postchallenge Hyperglycemia in Overweight and Obese Subjects: A New Marker of Impaired Glucose Regulation?
Authors: Diamantopoulos Emmanuel J. , Andreadis Emmanuel A. , Tsourous George I. , Katsanou Panagiota M. , Georgiopoulos Dimitrios X. , Dimitriadis George D. , Raptis Sotirios A.
Published: June 2007

The objective of this study was to compare subjects with intermediate postchallenge hyperglycemia (INPH) to those with normal glycemic status, impaired fasting glucose (IFG), and/or impaired glucose tolerance (IGT), as well as type 2 diabetes mellitus. Furthermore, the authors evaluated the impact of INPH on target organ damage. In total, 487 overweight and obese adults (BMI ≥27 kg/m2), 252 men and 235 women, mean age 52.9 ±10.2 years, were studied. All participants underwent a clinical and laboratory evaluation, as well as an oral glucose tolerance test (OGTT). They were also investigated by echocardiography, carotid ultrasonography, and pulse wave analysis. Overall, 302 (62%) subjects had normal glycemic status, 64 (13.1%) had IFG and/or IGT, 95 (19.5%) had type 2 diabetes mellitus, and 26 (5.4%) had INPH. Individuals with INPH had an increased index of insulin resistance (higher homeostasis model assessment-insulinogenic index [HOMA-IR], p<0.0001), impaired insulin secretion (lower insulinogenic index, p<0.0001), and higher glycosylated hemoglobin (HbA1c) levels (p<0.0001) in comparison with the normoglycemic subjects, but not to those with IFG and/or IGT or diabetes (p = 0.6). No difference was observed concerning the risk factors studied, left ventricular mass and vascular remodeling, among subjects with INPH, IFG and/or IGT, and diabetes. However, individuals with INPH had a higher proportion of echolucent carotid artery plaques in comparison with the normoglycemic subjects (p = 0.04) and those with IFG and/or IGT (p = 0.01). Intermediate postchallenge hyperglycemia seems to represent a new category of glucose metabolism disturbances with increased atherogenic impact. Therefore, evaluating intermediate glucose levels in an OGTT could contribute to better identify overweight individuals at risk of developing diabetes mellitus and cardiovascular events.
The Relationship Between Arterial Elasticity and Metabolic Syndrome Features
Authors: Fjeldstad Anette S. , Fjeldstad Cecilie , Acree Luke S. , Nickel Kevin J. , Montgomery Polly S. , Comp Philip C. , Whitsett Thomas L. , Gardner Andrew W.
Published: June 2007

The purpose of this study was to examine the effects of metabolic syndrome (MS) features on arterial elasticity of the large and small arteries in apparently healthy adults, to examine the effect of clustered features of MS, and to determine which features are most predictive of large and small artery elasticity. The subjects for this study consisted of 126 men and women, age 45 years and older. The subjects rested supine while pulse contour analysis was measured from the radial artery by using an HDI/Pulsewave CR-2000 instrument (Hypertension Diagnostic, Inc) to assess arterial elasticity in the large and small arteries. Medical history was obtained along with body mass index, waist circumference, body surface area, and blood pressure. Large artery elasticity was lower (p=0.002) in subjects with hypertension (12.7 ∓4.3 mL/mm Hg × 10) than in those with normotension (15.0 ∓4.2 mL/mm Hg × 10; mean ∓ SD), and small artery elasticity was lower (p=0.001) as well (3.9 ∓2.3 mL/mm Hg × 100 vs 5.3 ∓2.5 mL/mm Hg × 100). Large artery elasticity was lower (p=0.02) in obese subjects (12.2 ∓4.9 mL/mm Hg × 10) than in nonobese subjects (14.2 ∓4.5 mL/mm Hg × 10), and large artery elasticity was lower (p=0.04) in subjects with abdominal obesity (12.2 ∓4.5 mL/mm Hg × 10) than in those without (14.5 ∓4.8 mL/mm Hg × 10). Large artery elasticity decreased as the number of features of MS increased (p<0.01). Multiple regression showed that body mass index and the presence of hypertension were predictors of large artery elasticity (R =0.61, R 2 =0.37, p=0.003, SEE = 3.60 mL/mm Hg × 10), and hypertension was a predictor of small artery elasticity (R =0.53, R 2 =0.28, p=0.001, SEE = 2.12 mL/mm Hg × 100). Hypertension and obesity are the features of MS that are most predictive of impairment in large and small artery elasticity in apparently healthy middle-aged and older adults. Furthermore, impairment in large artery elasticity is more evident in subjects with at least three features of MS.