bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Fluid Loading on Hemodynamic Changes and Right Ventricular Function with Aortic Unclamping During Abdominal Aortic Surgery
Authors: Nakatsuka Mitsuru , Gupta Arun K. , Posner Marc P.
Published: August 2008

The authors investigated the effects of fluid loading on hemodynamic changes and right ventricular function (RVF) with aortic unclamping during abdominal aortic aneurysmal surgery in 12 patients. An ejection fraction volu metric pulmonary artery catheter was inserted through the right internal jugu lar vein to assess cardiac output and RVF with the use of an REF-1 computer. Anesthesia was maintained with a continuous infusion of sufentanil (0.5-1 μg/kg/hr), isoflurane (0.5-1%), and air/O2 (FIO2= 0.5). Fluid loading with Ring er's lactate and 5% albumin was initiated ten to twenty minutes before aortic unclamping. Hemodynamic measurements and assessment of RVF were per formed ten to twenty minutes before and after aortic unclamping. Aortic un clamping after fluid loading decreased right ventricular end-diastolic and end-systolic volumes (RVEDV, RVESV) but increased right ventricular ejection fraction (RVEF) (p < 0.01). There were no significant changes in cardiac index (CI), stroke volume (SV), systemic vascular resistance (SVR), and cardic filling pressures: central venous pressure (CVP), and pulmonary capillary wedge pres sure (PCWP). There was a poor correlation between RVEDV and PCWP. The authors conclude that adequate fluid loading before aortic unclamping, esti mated by RVEDV, provided stable hemodynamic states (CI, SV, RVEF) follow ing aortic unclamping. Volume expansion following fluid loading can be better assessed by RVEDV than by cardiac filling pressures.
Isolated Interruption of the Aortic Arch— A Case Report
Authors: Itrakjy A.J. , Nair K.K.
Published: August 2008

The authors report a case of a fifty-three-year-old man with isolated inter ruption of aortic arch without associated congenital anomalies. The anomaly was corrected with a 12 mm Dacron prosthetic graft from the subclavian artery to the distal segment of the descending aorta.
Bilateral Atherosclerotic Aneurysms of the Subclavian Arteries: Case Report
Authors: Yener Ali , Kaptanoglu Melih , Halit Velit , Ilgit Erhan T. , Altin Melik , Konus Öznur L.
Published: August 2008

A unique case of bilateral, saccular subclavian artery aneurysms and their treatment in a patient with massive atherosclerosis in the absence of a history of trauma and extrinsic vascular compression is presented with a brief review of the literature.
Homologous Cryopreserved Saphenous Vein for Construction of a "Jump" Arterioarterial Access for Hemodialysis—A Case Report
Authors: Slutzki Sam , Jaffe David , Nessing Meir , Bogokowsky Harry , Halevy Ariel
Published: August 2008

An alternative technique enabling vascular access for hemodialysis is de scribed. A forty-year-old man suffering from end-stage renal failure underwent a radioradial arterioarterial jump bypass. This was done successfully by using a cryopreserved venous homograft, which remained patent and functional for twenty-two months.
A False Aneurysm of the Proximal Common Carotid Artery: Evaluation and Management—A Case Report
Authors: Kiev Jonathan , Forman Mark H. , Kerstein Morris D.
Published: August 2008

A symptomatic proximal common carotid artery false aneurysm that oc curred ten years after the repair of an arteriovenous fistula caused by a stab wound to the neck was repaired by a reverse saphenous vein graft to restore continuity from the aortic arch to the common carotid artery.
Cardiac and Hemodynamic Effects of Infrarenal Aortic Clamping During Repair of Abdominal Aortic Aneurysms. A Reason for Combined Coronary Bypass and Aneurysm Repair in Patients with Severe Coronary Artery Disease
Authors: Carrel T. , Pasic M. , Schmid E.R. , Turina M.
Published: August 2008

Coronary disease is the leading cause of early and late death after any type of vascular operation, but its immediate implications are more serious in patients who require abdominal aortic reconstruction. Infrarenal cross-clamping required during aortic replacement is generally well tolerated but may occasionally lead to severe hemodynamic disturbances in patients suffering from coronary artery disease (CAD).

The authors performed prospective registration of hemodynamic and cardiac effects of infrarenal aortic clamping in three groups of 25 patients each who underwent infrarenal aortic aneurysm repair. Group I included patients without CAD, group II patients had manifest signs of CAD, whereas patients in group III underwent aortic repair immediately after coronary revascularization, as part of a combined approach.

Patients with CAD demonstrated significant increase of central venous pressure, pulmonary arterial pressure, and pulmonary capillary wedge pressure after aortic clamping. Cardiac output measurements showed a significant decrease while systemic vascular resistance increased. A majority of patients presented ischemic ECG alterations and/or arrhythmia. Patients of group III presented an intermediate response to aortic clamping as compared with cardiac-healthy patients of group I and coronary patients from group II. However, there were no signs of ischemia after cross-clamping in this group of patients.

The study demonstrates clearly the different tolerances to the stress of aortic cross-clamping in patients with and without CAD. Intraoperative transesophageal echocardiography allowed the authors to detect dilatation of the cardiac cavities following cross-clamping in patients with severe CAD; when this is not available, left ventricular filling pressure should be monitored in patients with CAD undergoing abdominal aortic repair. Registration of left ventricular pressure is a prerequisite for proper intraoperative application of vasodilators.
Functional Benefits of Peripheral Vascular Bypass Surgery for Patients with Intermittent Claudication
Authors: Regensteiner Judith G. , Hargarten Melanie E. , Rutherford Robert B. , Hiatt William R.
Published: August 2008

Many patients with peripheral arterial disease (PAD) undergo peripheral bypass surgery to relieve the symptom of intermittent claudication. However, measurement of graft patency alone, assessed by change in ankle blood pressure, may not adequately reflect the improvement in functional status following the operation. Fourteen patients with moderately severe intermittent claudication were evaluated before and after bypass surgery to assess changes in hemodynamics (by resting ankle-brachial indices-ABIs), exercise performance (by a graded treadmill protocol), and community-based walking ability (by a questionnaire that characterizes self-reported walking speed and distance). Six weeks after surgery, resting ABIs improved in surgical patients (from 0.56 ± 0.09 to 0.93 ± 0.16, P < 0.05). Peak treadmill walking time improved from 6.2 ± 5.9 to 11.8 ± 7.1 min (90%), peak oxygen consumption from 15.5 ± 6.5 to 19.1 ± 8.5 mL/kg/min (23%), and pain-free walking time from 1.5 ± 0.4 to 6.0 5.5 min (290%). Questionnaire scores for walking distance improved by 203% and for walking speed by 130% (all P < 0.05). After twelve weeks, improvements other than pain-free walking time were maintained. Changes in peak treadmill performance or questionnaire scores were not correlated with the initial ABI, changes in ABI six or twelve weeks after surgery, or the type or extent of bypass surgery. The results demonstrate that surgical treatment of PAD, indicated for the relief of intermittent claudication, improves exercise performance and self-reported community-based walking ability. The change in functional status of the patient is an important outcome of surgery that cannot be predicted from routine noninvasive testing alone and should be measured directly.
Intracranial Hemorrhage as the Synergistic Effect of Urokinase and Renal Dysfunction—A Case Report
Authors: Wyble Charles W. , Karabinis Vasilios D. , Kerstein Morris D.
Published: August 2008

This case report details a patient treated for a gangrenous toe by angioplasty, sympathectomy, and aortobifemoral grafting who arrived at the hospital with acute renal dysfunction and an occluded bypass graft. The patient had no abnormal results from coagulation studies and no absolute contraindications to urokinase therapy but died from intracranial hemorrhage. The authors believe that hemostatic system impairments related to renal dysfunction act synergistically with thrombolytic agents to produce abnormal bleeding. This case report suggests a synergistic interaction between acute renal dysfunction and urokinase therapy.
Predictive Value of Manual ECG-Monitored Exercise Test Before Abdominal Aortic or Peripheral Vascular Surgery
Authors: Kaaja Risto , Sell Henrik , Erkola Olli , Harjula Ari
Published: August 2008

The value of manual ECG-monitored exercise test was studied in 58 patients (39 men and 19 women) with intermittent claudication scheduled for abdominal or peripheral vascular surgery. There was a high incidence of well-known risk factors (hypercholesterolemia, smoking, and hypertension) in men and women. History of coronary artery disease (CAD) was present in 29.3% of the patients. No correlation was found between patients with single or multiple stenoses in lower extremity arteries (angiography) and CAD. Ischemic response (ECG) to manual exercise testing was positive in 14 patients (24.1%), of whom 2 (14.3%) had major cardiovascular postoperative complications. Both died of acute myocardial infarction within fourteen days. They had slow recovery (thirty to sixty minutes) of the ST segment (0.3-0.6 mV).

The authors conclude that manual exercise testing might reveal serious CAD in patients with severe occlusive peripheral arterial disease of the lower extremi ties. In cases with slow recovery of ischemic response to exercise, coronary by pass or angioplasty could be advantageous before major vascular surgery.
Tumor Vascularity in Left Atrial Myxoma Supplied by the Left Circumflex Artery—A Case Report
Authors: Aytemir Kudret , Nazli Nasih , Tokgözoğlu S. Lale , Demircin Metin , Özin Bülent
Published: August 2008

A sixty-four-year-old woman with a left atrial myxoma underwent coronary angiography to delineate the coronary anatomy before surgery. It was found that the coronary arteries were normal, but a "tumor neovascularization" could be seen that was supplied by the atrial branch of the left circumflex ar tery. Tumor neovascularization can sometimes be detected in highly vascular myxomas and is usually supplied by the right coronary artery. Here we report a rare case of tumor vascularization from the circumflex artery.
Adventitial Cystic Disease of the Popliteal Artery: Successful Surgical Treatment of 8 Cases
Authors: Yorulmaz Fatih , Çetingök Ugur , Doğan Orhan , Yücel Ertan
Published: August 2008

Adventitial cystic disease is a rare condition with an unknown etiology predominently seen in young men. The clinical presentation is of a sudden onset of unilateral calf claudication with a progressive course.

Between May, 1988, and April, 1992, 8 patients have been operated on with the diagnosis of adventitial cystic disease of the popliteal artery in the authors' clinic. In 1 of the patients the lesion was bilaterally present in both of the popliteal arteries.

Early diagnosis and surgical treatment are of utmost importance to the success of treatment. The preferred treatment is arterial resection with venous bypass. This is highly effective and has good long-term results.
Kinking of Aortobifemoral Graft as a Rare Complication: Case Report
Authors: Zengin Mustafa , Mavioglu Ilhan , Dogan Orhan Veli , Yücel Ertan
Published: August 2008

Aortobifemoral arterial bypass grafting (Y-graft) is an important operation in vascular surgery. Early complications of Y-graft implantation are generally technical and infrequent. These are postoperative hemorrhage, acute occlusion of graft limb, distal atheroembolism (trash foot), and early thrombosis of the graft.

Early occlusion of the graft is attributable to twisting or kinking of the graft in the retroperitoneal tunnel. In this patient, who was operated on at another center, the symptoms were seen six months after the operation. At the reoperation, both limbs of the Y-graft were found to be kinked in the retroperitoneal tunnel. The kink was solved and excised, and profundoplasty was applied to both of the deep femoral arteries.
The Effect of whole-Blood Transfusion on Survival of Patients with Breast Cancer: Why the Controversies?
Authors: Salsali Morteza
Published: August 2008

Disputes still arise about the adverse effect of perioperative transfusion on survival of patients with malignant solid tumors. In order to find some answers to these controversies the author has studied 880 new patients with operable breast cancer, among whom 486 (55.2%) had received perioperative transfusion. In 86% of the patients the tumor size, when known, measured 3.0 cm (T2) or less. In general the ten-year actuarial survival of the 486 transfused patients has been 59.9% versus 66.7% for 394 nontransfused ones, X2 = 4.47; d.o.f. = 1, P <0.05.

In multivariate analysis it was noted that only positive nodes had affected the survival significantly (P = 10-9) and blood group had produced a trend (P = 0.08). However, when the period cohort was eliminated, the adverse effect of transfusion became evident in patients with blood group A in the 1968-69 and 1970-71 cohorts but not in those with blood group O.

It is concluded that the combined effect of transfusion and blood group, as a risk factor, is not as strong as positive nodes and large size of tumor. This study confirms that transfusion effect, at surgery, is a blood-group-related phenomenon.
The Role of Leukotrienes in Controlling Postischemic Skeletal Muscle Function
Authors: Homer-Vanniasinkam Shervanthi , Gough Michael J.
Published: August 2008

This study investigates the role of leukotrienes in controlling postischemic alterations in skeletal muscle edema and viability. In a rodent model of six-hour unilateral hindlimb ischemia and four-hour reperfusion, gastrocnemius muscle edema (GME, wet:dry weight ratio) and viability (GMV, nitroblue tetrazolium) were assessed and indices calculated to compare results from the reperfused limb with those from the contralateral normal limb. The influence of leukotrienes B4(LTB4) and C4D4E4(peptidoleukotrienes, PLT) on these changes was assessed by employing specific receptor antagonists (RA) to these mediators, infused intravenously from thirty minutes prior to and throughout reperfusion. Normal (N; ten-hour general anesthesia, no ischemia) and ischemic animals (I; six-hour ischemia only) did not develop either muscle edema or necrosis (GME-N: 1.00 [0.98-1.01], I: 1.01 [0.99-1.03]; GMV-N: 1.00 [1.00-1.00], I: 1.00 [1.00-1.00]) while control animals (C; ischemia and reperfusion alone) demonstrated both (GME: 1.23 [1.09-1.37]; GMV: 0.53 [0.33-0.61]; P<0.01 vs N,I). In rats receiving the LTB4 RA (SC 41930, 1 mg/kg) muscle viability was preserved, GMV: 1.00 (1.00-1.00), P<0.01 vs C and muscle edema reduced (GME: 1.08 [1.05-1.10], P<0.01 vs C). In contrast the PLT RA (ICI 198615, 550 μg/kg) promoted a further deterioration in viability (GMV: 0.29 [0.17-0.33], P<0.05 vs C; P<0.01 vs N,I) with no amelioration of edema (GME: 1.26 [1.20-1.31], ns vs C). These results demonstrate that postischemic skeletal muscle injury is controlled by leukotrienes, with PLT having a beneficial role and LTB4 appearing to enhance reperfusion injury.
Endotoxemia: Its Relationship to Colonic Ischemia and Aortic Surgery
Authors: Welch Mark , Durrans David , Douglas Jessie T. , Carr H. Martyn H. , Smyth J. Vincent , Walker Michael G.
Published: August 2008

Ten patients undergoing elective infrarenal aortic surgery were studied. Samples were taken perioperatively from a sigmoid tonometer to determine intramucosal pH (pHi) of the sigmoid colon, and simultaneously venous blood was taken for endotoxin measurement. Colonoscopy and biopsy were performed preoperatively and one week postoperatively. Significant endotoxemia was detected in 5 patients (50%), all of whom had transient colonic ischemia on the basis of tonometry, and of whom 2 had histologic evidence of ischemia at one week. Endotoxemia does occur during aortic surgery and appears to be associated with colonic ischemia, though this requires further evaluation.
Surgical Reconstruction and Muscular Augmentation of Ventricular Repairs: Their Impact on Compliance and Stroke Volume by Computer Simulations
Authors: Kim Francis , Yee Edward S.
Published: August 2008

Computer simulation techniques were used to explore direct versus patch reconstructive repairs on left ventricular dynamics after damages of myocardial infarction, aneurysmal dilatation, and compensatory hypertrophy This ellipsoid geometric modeling allowed further assessment of these three pathological stages on left ventricular compliance (dV/dP) and stroke volume (SV). Primary surgical closure after any myocardium resection created a smaller ventricular cavity and, thus, decreased SV Similarly, dV/dP by direct closure is markedly in each of these three transitional stages. In comparison, for the patch repair techniques, SV after augmentation by skeletal muscle ventriculoplasty offered the most immediate recovery after acute apical infarct with relatively little change in dV/dP Synthetic patch repair after aneurysmal and/or hypertrophy formation preserved the best SV despite negative shifts in dV/dP Therefore, maintaining geometric shape and retaining functional continuity are important operative considerations for optimizing SV and minimizing the negative impact in dV/dP

Computer simulation models have been extensively used to predict the impact of various operative repair on ventricular compliance and stroke volume. These techniques allow detailed evaluation of newer or experimental reconstructive surgical procedures such as skeletal muscle ventriculoplasty.
Esmolol or Sodium Nitroprusside for Induced Hypotension During Isoflurane Anesthesia
Authors: Shah Nitin , DelValle Oscar , Edmondson Richard , Zaccari June , Bedford Robert , Herr H.
Published: August 2008

This study examines the effects of esmolol (E) and sodium nitroprusside (SNP) in inducing hypotension during isoflurane (I) anesthesia. Nineteen men (E = 10, SNP = 9) undergoing genitourinary surgery were studied. Cardiovascular, endocrine (catecholamine levels and plasma renin activity [PRA]), and arterial blood gas data were collected before, during, and after hypotension employing infusions of SNP at 0.5, 1.0, or 2.0 μg/kg/min or E at 75, 150, or 300 μg/kg/min. The hypotensive agent and its dosage sequence were chosen randomly Compared with preinduction values, there was no difference in the PRA or the heart rate during hypotension in the E group, but in the SNP group, both increased significantly Furthermore, the authors also observed a linear, dose-dependent reduction in I requirement with increasing doses of SNP, whereas with E, the I requirement decreased only with the higher dose. Arterial oxygenation also worsened with SNP as compared with E during hypotension. The authors conclude that during I anesthesia, E appears to be a better agent than SNP for induced hypotension.
Optical and Electrical Properties of Polycarbonate/MnCl2 Composite Films
Authors: Ayesh Ayman S. , Abdel-Rahem Rami A.
Published: August 2008

The dependence of the absorption coefficient (α) on photon energy (hν) is determined in the spectral range from 200 to 800 nm at room temperature for polycarbonate (PC)/MnCl2 composite films. The variation of the absorption coefficient (α), optical gap (Eopt), dielectric permittivity (ε'), dielectric loss (ε''), loss tangent (tan δ), impedance (Z), AC conductivity (σac), DC conductivity (σdc), and relaxation time (τ) with salt concentration and frequency are reported. The observed optical energy gap (Eopt) and energy gap tail (▵E) is calculated from the measured absorption spectra. It is found that optical energy gap decreases with increasing MnCl2 concentration and the absorption coefficient reduces sharply (with reduction ratio of 79%) in the UV region at concentration of 20 wt% compared with the PC host. All measured electrical parameters of the composite sheets show frequency and content dependence. Both AC conductivity and DC conductivity increase with MnCl2 concentration while impedance decreases. Correlation between observed energy gap and AC conductivity is presented.
PTP1B is a negative regulator of interleukin 4–induced STAT6 signaling
Authors: Lu Xiaoqing , Malumbres Raquel , Shields Benjamin , Jiang Xiaoyu , Sarosiek Kristopher A. , Natkunam Yasodha , Tiganis Tony , Lossos Izidore S.
Published: August 2008

Protein tyrosine phosphatase 1B (PTP1B) is a ubiquitously expressed enzyme shown to negatively regulate multiple tyrosine phosphorylation-dependent signaling pathways. PTP1B can modulate cytokine signaling pathways by dephosphorylating JAK2, TYK2, and STAT5a/b. Herein, we report that phosphorylated STAT6 may serve as a cytoplasmic substrate for PTP1B. Overexpression of PTP1B led to STAT6 dephosphorylation and the suppression of STAT6 transcriptional activity, whereas PTP1B knockdown or deficiency augmented IL-4–induced STAT6 signaling. Pretreatment of these cells with the PTK inhibitor staurosporine led to sustained STAT6 phosphorylation consistent with STAT6 serving as a direct substrate of PTP1B. Furthermore, PTP1B-D181A “substrate-trapping” mutants formed stable complexes with phosphorylated STAT6 in a cellular context and endogenous PTP1B and STAT6 interacted in an interleukin 4 (IL-4)–inducible manner. We delineate a new negative regulatory loop of IL-4–JAK-STAT6 signaling. We demonstrate that IL-4 induces PTP1B mRNA expression in a phosphatidylinositol 3-kinase–dependent manner and enhances PTP1B protein stability to suppress IL-4–induced STAT6 signaling. Finally, we show that PTP1B expression may be preferentially elevated in activated B cell–like diffuse large B-cell lymphomas. These observations identify a novel regulatory loop for the regulation of IL-4–induced STAT6 signaling that may have important implications in both neoplastic and inflammatory processes.
Five new pedigrees with inherited RUNX1 mutations causing familial platelet disorder with propensity to myeloid malignancy
Authors: Owen Carolyn J. , Toze Cynthia L. , Koochin Anna , Forrest Donna L. , Smith Clayton A. , Stevens Jane M. , Jackson Shannon C. , Poon Man-Chiu , Sinclair Gary D. , Leber Brian , Johnson Peter R. E. , Macheta Anthony , Yin John A. L. , Barnett Michael J. , Lister T. Andrew , Fitzgibbon Jude
Published: August 2008

Familial platelet disorder with propensity to myeloid malignancy (FPD/AML) is an autosomal dominant syndrome characterized by platelet abnormalities and a predisposition to myelodysplasia (MDS) and/or acute myeloid leukemia (AML). The disorder, caused by inherited mutations in RUNX1, is uncommon with only 14 pedigrees reported. We screened 10 families with a history of more than one first degree relative with MDS/AML for inherited mutations in RUNX1. Germ- line RUNX1 mutations were identified in 5 pedigrees with a 3:2 predominance of N-terminal mutations. Several affected members had normal platelet counts or platelet function, features not previously reported in FPD/AML. The median incidence of MDS/AML among carriers of RUNX1 mutation was 35%. Individual treatments varied but included hematopoietic stem cell transplantation from siblings before recognition of the inherited leukemogenic mutation. Transplantation was associated with a high incidence of complications including early relapse, failure of engraftment, and posttransplantation lymphoproliferative disorder. Given the small size of modern families and the clinical heterogeneity of this syndrome, the diagnosis of FPD/AML could be easily overlooked and may be more prevalent than previously recognized. Therefore, it would appear prudent to screen young patients with MDS/AML for RUNX1 mutation, before consideration of sibling hematopoietic stem cell transplantation.
Nuclear survivin in pN2 nonsmall cell lung cancer: prognostic and clinical implications
Authors: Mohamed S. , Yasufuku K. , Nakajima T. , Hiroshima K. , Chiyo M. , Yoshida S. , Suzuki M. , Sekine Y. , Shibuya K. , Agamy G. , El-Shahhat H. , Fujisawa T. , Yoshino I.
Published: August 2008

Patients with N2 nonsmall cell lung cancer (N2-NSCLC) represent heterogeneous groups. Survivin is a member of the inhibitor of apoptosis family. If N2-NSCLC patients could be stratified, based on survivin expression and/or its relation to cell cycle proteins, into homogeneous subgroups, certain therapies could be selected for those patients.

Survivin expression in 78 surgically resected primary pathological N2-NSCLC tumours was evaluated using immunohistochemistry. Relationships of survivin expression to overall survival, clinical features and expression of six cell cycle-related proteins (pRb, cyclin D1, p16INK4A, p53, p21Waf1and Ki-67) were analysed.

Nuclear survivin and the number of mediastinal lymph node (LN) stations were independent prognostic factors. The patient group with combined negative survivin/single mediastinal LN station were the most favourable prognostic group, and was related to the clinical nodal factor. Indeed, patients with negative survivin/low Ki-67 labelling indices had the best survival, especially in nonsquamous histopathology.

The current authors conclude that nuclear survivin is strongly related to lymph node metastasis and proliferative potentials in pathological N2 nonsmall cell lung cancer patients. Pre-operative N2 nonsmall cell lung cancer patients with combined negative nuclear survivin and a single mediastinal lymph node station, or low proliferative indices, particularly in clinical N0-1 disease and nonsquamous histopathology, respectively, are expected to have a favourable post-operative prognosis and may be candidates for primary resection.
Pseudomonas aeruginosatransmission is infrequent in New Zealand cystic fibrosis clinics
Authors: Schmid J. , Ling L. J. , Leung J. L. S. , Zhang N. , Kolbe J. , Wesley A. W. , Mills G. D. , Brown P. J. , Jones D. T. , Laing R. T. R. , Pattemore P. K. , Taylor D. R. , Grimwood K.
Published: August 2008

Pseudomonas aeruginosais an important pathogen in cystic fibrosis (CF). Although most patients harbour uniqueP. aeruginosaisolates, some clinics report patients sharing common strains. The overall importance of person-to-person transmission inP. aeruginosaacquisition and whether routine patient segregation is necessary remains uncertain. The present authors therefore investigated the extent ofP. aeruginosatransmission in New Zealand CF clinics.

New Zealand’s seven major CF centres were assessed, combining epidemiological data with computer-assistedSalI DNA fingerprinting of 496 isolates from 102 patients.

One cluster of related isolates was significantly more prevalent in the largest clinic than expected by chance. The seven patients with isolates belonging to this cluster had more contact with each other than the remaining patients attending this centre. No other convincing evidence of transmission was found in any of the other smaller clinics. ThreeP. aeruginosastrains believed to be transmissible between patients in Australian and British CF clinics are present in New Zealand, but there was no definite evidence they had spread.

Pseudomonas aeruginosatransmission is currently infrequent in New Zealand cystic fibrosis clinics. This situation could change rapidly and ongoing surveillance is required. The current results confirm that computer-assistedSalI DNA fingerprinting is ideally suited for such surveillance.
Transcriptome analysis reveals response regulator SO2426-mediated gene expression in Shewanella oneidensis MR-1 under chromate challenge
Authors: Chourey Karuna , Wei Wei , Wan Xiu-Feng , Thompson Dorothea K
Published: August 2008

Background

Shewanella oneidensis MR-1 exhibits diverse metal ion-reducing capabilities and thus is of potential utility as a bioremediation agent. Knowledge of the molecular components and regulatory mechanisms dictating cellular responses to heavy metal stress, however, remains incomplete. In a previous work, the S. oneidensis so2426 gene, annotated as a DNA-binding response regulator, was demonstrated to be specifically responsive at both the transcript and protein levels to acute chromate [Cr(VI)] challenge. To delineate the cellular function of SO2426 and its contribution to metal stress response, we integrated genetic and physiological approaches with a genome-wide screen for target gene candidates comprising the SO2426 regulon.

Results

Inactivation of so2426 by an in-frame deletion resulted in enhanced chromate sensitivity and a reduced capacity to remove extracellular Cr(VI) relative to the parental strain. Time-resolved microarray analysis was used to compare transcriptomic profiles of wild-type and SO2426-deficient mutant S. oneidensis under conditions of chromate exposure. In total, 841 genes (18% of the arrayed genome) were up- or downregulated at least twofold in the Δso2426 mutant for at least one of six time-point conditions. Hierarchical cluster analysis of temporal transcriptional profiles identified a distinct cluster (n = 46) comprised of co-ordinately regulated genes exhibiting significant downregulated expression (p < 0.05) over time. Thirteen of these genes encoded proteins associated with transport and binding functions, particularly those involved in Fe transport and homeostasis (e.g., siderophore biosynthetic enzymes, TonB-dependent receptors, and the iron-storage protein ferritin). A conserved hypothetical operon (so1188-so1189-so1190), previously identified as a potential target of Fur-mediated repression, as well as a putative bicyclomycin resistance gene (so2280) and cation efflux family protein gene (so2045) also were repressed in the so2426 deletion mutant. Furthermore, the temporal expression profiles of four regulatory genes including a cpxR homolog were perturbed in the chromate-challenged mutant.

Conclusion

Our findings suggest a previously unrecognized functional role for the response regulator SO2426 in the activation of genes required for siderophore-mediated Fe acquisition, Fe storage, and other cation transport mechanisms. SO2426 regulatory function is involved at a fundamental molecular level in the linkage between Fe homeostasis and the cellular response to chromate-induced stress in S. oneidensis.
Antimicrobial activity of some sulfonamide derivatives on clinical isolates of Staphylococus aureus
Authors: Genç Yeliz , Özkanca Reşit , Bekdemir Yunus
Published: August 2008

Background

Staphylococcus aureus is a non-motile, gram positive, non-sporforming, facultative anaerobic microorganism. It is one of the important bacteria as a potential pathogen specifically for nosocomial infections. The sulfonamide derivative medicines are preferred to cure infection caused by S. aureus due to methicillin resistance.

Methods

Antimicrobial activity of four sulfonamide derivatives have been investigated against 50 clinical isolates of S. aureus and tested by using MIC and disc diffusion methods. 50 clinical isolate which collected from specimens of patients who are given medical treatment in Ondokuz Mayis University Medical School Hospital. A control strain of S. aureus ATCC 29213 was also tested.

Results

The strongest inhibition was observed in the cases of I [N-(2-hydroxy-4-nitro-phenyl)-4-methyl-benzensulfonamid], and II [N-(2-hydroxy-5-nitro-phenyl)-4-methyl-benzensulfonamid] against S. aureus. Compound I [N-(2-hydroxy-4-nitro-phenyl)-4-methyl-benzensulfonamid] showed higher effect on 21 S. aureus MRSAisolates than oxacillin antibiotic. Introducing an electron withdrawing on the ring increased the antimicrobial activity remarkably.

Conclusion

This study may help to suggest an alternative possible leading compound for development of new antimicrobial agents against MRSA and MSSA resistant S. aureus. It was also shown here that that clinical isolates of 50 S. aureus have various resistance patterns against to four sulfonamide derivatives. It may also be emphasized here that in vitro antimicrobial susceptibility testing results for S. aureus need standardization with further studies and it should also have a correlation with in vivo therapeutic response experiments.
Development of a health care utilisation data-based index for rheumatoid arthritis severity: a preliminary study
Authors: Ting Gladys , Schneeweiss Sebastian , Scranton Richard , Katz Jeffrey N , Weinblatt Michael E , Young Melissa , Avorn Jerry , Solomon Daniel H
Published: August 2008

Introduction

Health care utilisation ('claims') databases contain information about millions of patients and are an important source of information for a variety of study types. However, they typically do not contain information about disease severity. The goal of the present study was to develop a health care claims index for rheumatoid arthritis (RA) severity using a previously developed medical records-based index for RA severity (RA medical records-based index of severity [RARBIS]).

Methods

The study population consisted of 120 patients from the Veteran's Administration (VA) Health System. We previously demonstrated the construct validity of the RARBIS and established its convergent validity with the Disease Activity Score (DAS28). Potential claims-based indicators were entered into a linear regression model as independent variables and the RARBIS as the dependent variable. The claims-based index for RA severity (CIRAS) was created using the coefficients from models with the highest coefficient of determination (R2) values selected by automated modelling procedures. To compare our claims-based index with our medical records-based index, we examined the correlation between the CIRAS and the RARBIS using Spearman non-parametric tests.

Results

The forward selection models yielded the highest model R2 for both the RARBIS with medications (R2 = 0.31) and the RARBIS without medications (R2 = 0.26). Components of the CIRAS included tests for inflammatory markers, number of chemistry panels and platelet counts ordered, rheumatoid factor, the number of rehabilitation and rheumatology visits, and Felty's syndrome diagnosis. The CIRAS demonstrated moderate correlations with the RARBIS with medication and the RARBIS without medication sub-scales.

Conclusion

We developed the CIRAS that showed moderate correlations with a previously validated records-based index of severity. The CIRAS may serve as a potentially important tool in adjusting for RA severity in pharmacoepidemiology studies of RA treatment and complications using health care utilisation data.
Disruption of the thrombospondin-2 gene alters the lamellar morphology but does not permit vascularization of the adult mouse lumbar disc
Authors: Gruber Helen E , Bornstein Paul , Sage E Helene , Ingram Jane A , Zinchenko Natalia , Norton H James , Hanley Edward N
Published: August 2008

Introduction

The biological basis for the avascular state of the intervertebral disc is not well understood. Previous work has suggested that the presence of thrombospondin-1 (TSP-1), a matricellular protein, in the outer annulus reflects a role for this protein in conferring an avascular status to the disc. In the present study we have examined thrombospondin-2 (TSP-2), a matricellular protein with recognized anti-angiogenic activity in vivo and in vitro.

Methods

We examined both the location and expression of TSP-2 in the human disc, and its location in the disc and bordering soft tissues of 5-month-old normal wild-type (WT) mice and of mice with a targeted disruption of the TSP-2 gene. Immunohistochemistry and quantitative histology were utilized in this study.

Results

TSP-2 was found to be present in some, but not all, annulus cells of the human annulus and the mouse annulus. Although there was no difference in the number of disc cells in the annulus of TSP-2-null mice compared with that of WT animals, polarized light microscopy revealed a more irregular lamellar collagen structure in null mouse discs compared with WT mouse discs. Additionally, vascular beds at the margins of discs of TSP-2-null mice were substantially more irregular than those of WT animals. Counts of platelet endothelial cell adhesion molecule-1-positive blood vessels in the tissue margin bordering the ventral annulus showed a significantly larger vascular bed in the tissue bordering the disc of TSP-2-null mice compared with that of WT mice (P = 0.0002). There was, however, no vascular ingrowth into discs of the TSP-2-null mice.

Conclusion

These data confirm a role for TSP-2 in the morphology of the disc and suggest the presence of other inhibitors of angiogenesis in the disc. We have shown that although an increase in vasculature was present in the TSP-2-null tissue in the margin of the disc, vascular ingrowth into the body of the disc did not occur. Our results point to the need for future research to understand the transition from the well-vascularized status of the fetal and young discs to the avascular state of the adult human disc or the small mammalian disc.
Relaxin reduces xenograft tumour growth of human MDA-MB-231 breast cancer cells
Authors: Radestock Yvonne , Hoang-Vu Cuong , Hombach-Klonisch Sabine
Published: August 2008

Introduction

Relaxin levels are increased in cases of human breast cancer and has been shown to promote cancer cell migration in carcinoma cells of the breast, prostate gland and thyroid gland. In oestrogen receptor alpha-negative MDA-MB-231 human breast cancer cells, relaxin was shown to down-regulate the metastasis-promoting protein S100A4 (metastasin), a highly significant prognostic factor for poor survival in breast cancer patients. The cellular mechanisms of relaxin exposure in breast cancer cells are not fully understood. The aim of this study was to investigate short-term and long-term effects of relaxin on cancer cell motility and S100A4 expression and to determine the long-term effects of relaxin on in vivo tumour growth in an oestrogen-independent context.

Method

We have established stable transfectants of highly invasive oestrogen-receptor alpha-negative MDA-MB-231 human breast cancer cells with constitutive expression of bioactive H2-relaxin (MDA/RLN2). RLN2 secretion was determined by ELISA. Relaxin receptor RXFP1 (Relaxin-family-peptide) was detected by reverse transcription (RT) PCR and its activation was assessed by induction of cyclic adenosine monophosphate (cAMP). Stable MDA/RLN2 clones and RLN2 treated MDA-MB-231 cells were subjected to motility and in vitro-invasion assays. Proliferation was assessed in bromodeoxyuridine (BrdU) and MTT assays. S100A4 expression was determined by RT-PCR and Western blot. Specific small interfering RNA was employed to down-regulate relaxin receptor and S100A4. MDA/EGFP vector control and two MDA/RLN2 clones were injected subcutaneously in nude mice to determine tumour growth and cancer cell invasiveness in vivo. Xenograft tumour tissues were assessed by histology and immunohistochemistry and frozen tissues were used for the detection of S100A4 and RLN2.

Results

Short-term exposure to relaxin for 24 hours increased cell motility in a relaxin receptor-dependent manner. This increase in cell motility was mediated by S100A4. Long-term exposure to relaxin secreted from stable transfectants reduced cell motility and in vitro invasiveness. Relaxin decreased cell proliferation and down-regulated cellular S100A4 levels in MDA-MB-231 and T47D breast cancer cells. Stable MDA/RLN2 transfectants produced smaller xenograft tumours containing reduced S100A4 protein levels in vivo.

Conclusion

Our results indicate that long-term exposure to relaxin confers growth inhibitory and anti-invasive properties in oestrogen-independent tumours in vivo, which may in part be mediated through a down-regulation of S100A4.
Efficient Correlation Matching for Fitting Discrete Multivariate Distributions with Arbitrary Marginals and Normal-Copula Dependence
Authors: Avramidis Athanassios N. , Channouf Nabil , L'Ecuyer Pierre
Published: August 2008

A popular approach for modeling dependence in a finite-dimensional random vector X with given univariate marginals is via a normal copula that fits the rank or linear correlations for the bivariate marginals of X. In this approach, known as the NORTA method, the normal distribution function is applied to each coordinate of a vector Z of correlated standard normals to produce a vector U of correlated uniform random variables over (0,1); then X is obtained by applying the inverse of the target marginal distribution function for each coordinate of U. The fitting requires finding the appropriate correlation ρ between any two given coordinates of Z that would yield the target rank or linear correlation r between the corresponding coordinates of X. This root-finding problem is easy to solve when the marginals are continuous but not when they are discrete. In this paper, we provide a detailed analysis of this root-finding problem for the case of discrete marginals. We prove key properties of r and of its derivative as a function of ρ. It turns out that the derivative is easier to evaluate than the function itself. Based on that, we propose and compare alternative methods for finding or approximating the appropriate ρ. The case of discrete distributions with unbounded support is covered as well. In our numerical experiments, a derivative-supported method is faster and more accurate than a state-of-the-art, nonderivative-based method. We also characterize the asymptotic convergence rate of the function r (as a function of ρ) to the continuous-marginals limiting function, when the discrete marginals converge to continuous distributions.
Governance-Knowledge Fit in Systems Development Projects
Authors: Tiwana Amrit
Published: August 2008

This study addresses the theoretically underexplored question of how fit between project governance configurations, and the knowledge of specialized information technology (IT) and client departments, influences information systems development (ISD) performance. It conceptualizes project governance configurations using two classes of project decisions rights—decision control rights and decision management rights. The paper then develops a middle-range theory of how governance-knowledge fit shapes ISD performance by influencing the effective exercise of these decision rights during the development process. Further, the two dimensions of ISD performance—efficiency and effectiveness—are shaped by different classes of project decision rights. Data from 89 projects in 89 firms strongly support the proposed ideas. Implications for theory and practice are also discussed.
An investigation of cross‐national differences in positivity and job satisfaction
Authors: Mueller Karsten , Hattrup Keith , Hausmann Natascha
Published: August 2008

The present research examined the role of national differences in positivity as an explanation of cross‐national variation in job satisfaction (JS) ratings. National positivity values were derived from a sample of current employees by calculating the mean residual in a regression of global JS on mean facet satisfaction ratings. As predicted, the positivity values derived in the present research showed convergent validity with other indices of nation‐level positivity, and national differences in extraversion. National differences in positivity showed significant incremental associations with national differences in JS ratings after controlling for the effects of acquiescence, perceived differences in working conditions, and national development. Theoretical and practical implications of the results are discussed.
Decision‐making about pregnancy for women with cystic fibrosis
Authors: Simcox Angela M. , Hewison Jenny , Duff Alistair J. A. , Morton Alison M. , Conway Steven P.
Published: August 2008

ObjectivesThis study aims to generate experiential data about the decision‐making process encountered by 12 women with cystic fibrosis (CF) considering pregnancy.

DesignThis study uses a qualitative grounded theory methodology to analyse the data and develop a conceptual hierarchical model of salient issues.

MethodsTwelve women completed a semi‐structured interview accompanied by quantitative self‐report measures of quality of life and psychological well‐being, and indicators of health and treatment status were used.

ResultsDescriptive data demonstrated that the sample did not differ significantly from other published samples. Four core categories emerged: (1) impact of the decision; (2) preparation for making and living with the decision; (3) owning the decision; and (4) personal dilemmas. Each comprised a number of overlapping conceptual and subcategories. Influencing factors included the impact of pregnancy on participants' health, and upon their ability to care for the child, the pregnancy experiences of other women with CF, the moral implications of having a child and the support and beliefs of family members.

DiscussionThe findings extend the current knowledge in this area. We recommend development of guidelines for supporting and advising chronically ill young women about the psychosocial and emotional issues.
Multidisciplinary allocation of chronic pain treatment: Effects and cognitive‐behavioural predictors of outcome
Authors: Samwel Han J. A. , Kraaimaat Floris W. , Crul Ben J. P. , van Dongen Robert D. , Evers Andrea W. M.
Published: August 2008

Objectives. Multidisciplinary treatment approaches have been found to be effective for chronic pain patients although there are large individual differences in outcomes. To increase overall treatment effects, tools are needed to identify patients most likely to benefit from tailored, comprehensive modular treatment schemes.

Design. The present study evaluates the effects of a multidisciplinary pain treatment allocation protocol in chronic pain patients and seeks to identify cognitive‐behavioural predictors of outcome. Pain intensity, functional disability, depression, and use of medication in an intervention group of 110 chronic pain patients were compared to the outcomes of a 110 strong control group.

Results. Paired pre‐ and post‐treatmentttests showed that all primary outcomes had significantly decreased in the intervention group with ANCOVAs revealing a main group effect for post‐treatment pain intensity levels and functional disability. Pairedttests demonstrated both variables to have significantly reduced after treatment relative to the levels reported by the control group. Predictor analyses further showed higher levels of acceptance to significantly predict larger reductions in pain intensity in the intervention but not in the control group.

Conclusion. The tested multidisciplinary allocation scheme for out‐patient treatment of chronic pain complaints was effective in reducing pain intensity and functional disability. Findings also showed that especially those patients that are able to accept their condition are likely to profit most from the treatment in terms of pain reduction.