bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyperechoic Plaque: An Ultrasound Marker for Osteoporosis in Acute Stroke Patients with Carotid Disease
Authors: Saverino A. , Del Sette M. , Conti M. , Ermirio D. , Ricca M. , Rovetta G. , Gandolfo C.
Published: February 2006

Background: Osteoporosis is a significant complication of stroke, and hip fracture after a stroke is a frequent problem. Moreover, growing evidence links vascular and bone diseases, in the form of osteoporosis associated with both atherosclerosis and vascular calcification. The aim of our study is to detect bone change in the acute phase of ischemic stroke in patients with carotid disease and to verify the correlation with carotid echogenic plaques. Patients and Method: Out of 245 subjects consecutively admitted to our Stroke Unit for their first ischemic stroke, we selected 49 patients with a first-ever stroke due to carotid atherosclerosis without a previous diagnosis of bone disease. We assessed risk factors for cerebrovascular disease as well as for osteoporosis, the degree of neurological deficit and disability, and bone mineral density that was quantified by bilateral hip dual energy X-ray absorbimetry. Osteoporosis was defined as a T score below –2.5. Carotid ultrasound was used to classify plaques in non-hyperechoic (grade 1) and hyperechoic plaque (grade 2). Results: We found a high prevalence of low bone mass density (BMD) in our patients (18 out of 49 = 36.7%), without relationship to the side of paresis. According to univariate analysis evidence of osteoporosis was correlated with age (p = 0.05), score of Scandinavian Stroke Scale (p = 0.01) and grade 2 plaque (p = 0.01). According to multivariate analysis, there was a significant positive correlation between grade 2 plaques and osteoporosis (OR = 6.58; 95% CI = 1.57–27.54; p = 0.01), which was stronger in women (OR = 18.15; 95% CI = 1.80–182.83; p = 0.01). The percentage of intraplaque hyperechogenicity was inversely correlated with BMD (r = –0.411, p = 0.016). Conclusion: Osteoporosis is highly prevalent in acute atherosclerotic stroke patients. Carotid hyperechoic plaque is an independent marker of osteoporosis.
Glossopharyngeal Neuralgia
Authors: Pearce J.M.S.
Published: February 2006

Glossopharyngeal neuralgia is a distinctive syndrome, named by Wilfred Harris. Investigation must exclude multiple sclerosis, and local compression, especially by tumours which require treatment. Dandy deserves credit for first indicating vascular compression of cranial nerve roots as a cause of cranial neuralgias, and Jannetta for establishing neurovascular decompression. Vascular compression is a common and treatable cause but does not account for all previously designated idiopathic cases.
Sir William Withey Gull (1816–1890)
Authors: Pearce J.M.S.
Published: February 2006

William Gull, a man of humble origins, became one of the outstanding, polymath physicians of the 19th century, and physician to Queen Victoria. Among several important and original contributions, this paper summarises his work on myxoedema, paraplegia and anorexia nervosa.
A Norse Contribution to the History of Neurological Diseases
Authors: Holmøy Trygve
Published: February 2006

Multiple sclerosis (MS) is prevalent in areas with many inhabitants of Scandinavian descent, and a ‘Viking gene’ hypothesis has been suggested for the dissemination of the disease. It is therefore relevant to search Norse sagas for descriptions of clinical pictures which could have been MS. The saga of Bishop Thorlak describes a woman named Halldora, who suffered from transient paresis between 1193 and 1198. The diagnosis is uncertain, but the story shows that symptoms associated with MS were known in Iceland at the end of the 11th century.
A High-Resolution Single Photon Emission Computed Tomography Study of Verbal Recognition Memory in Alzheimer’s Disease
Authors: Trollor Julian N. , Sachdev Perminder S. , Haindl Walter , Brodaty Henry , Wen Wei , Walker Brenda M.
Published: February 2006

Background: In view of the recent technological advances and its ease of availability, we used single photon emission computed tomography (SPECT) to examine the performance of early Alzheimer’s disease (AD) subjects on a verbal recognition memory task. Methods: Eighteen early AD and 10 matched healthy control subjects underwent split-dose 99mTc-HMPAO (Ceretec®) SPECT using a verbal recognition memory and control task. SPECT images co-registered with MRI scans were used to determine relative regional cerebral blood flow (rCBF) changes in regions of interest. Results: In healthy control subjects, verbal recognition increased rCBF in the right occipital region, thalamus, left prefrontal pole, posterior parietal region and cerebellum, and decreased rCBF in the right hippocampus. AD subjects showed bilateral prefrontal, posterior parietal and occipital increases, unilateral increase in the left posterior temporal region, and bilateral reductions in the hippocampus. Although activation was significantly different between the two groups in the right thalamus and left medial prefrontal region, the verbal recognition task did not enhance discrimination between groups. Conclusions: Compared with controls, AD subjects activate a similar but more extensive bilateral network during verbal recognition, possibly reflecting an attempt to compensate for impaired processing.
Clinical Determinants of Dementia and Mild Cognitive Impairment following Ischaemic Stroke: The Sydney Stroke Study
Authors: Sachdev P.S. , Brodaty H. , Valenzuela M.J. , Lorentz L. , Looi J.C.L. , Berman K. , Ross A. , Wen W. , Zagami A.S.
Published: February 2006

Background: Dementia following stroke is common but its determinants are still incompletely understood. Methods: In the Sydney Stroke Study, we performed detailed neuropsychological and medical-psychiatric assessments on 169 patients aged 50–85 years, 3–6 months after a stroke, and 103 controls with a majority of both groups undergoing MRI brain scans. Stroke subjects were diagnosed as having vascular mild cognitive impairment (VaMCI) or vascular dementia (VaD) or no cognitive impairment by consensus. Demographic, functional, cerebrovascular risk factors and neuroimaging parameters were examined as determinants of dementia using planned logistic regression. Results: 21.3% of subjects were diagnosed with VaD, with one case in those aged 50–59 years, 24% in those aged 60–69 years and 23% in those 70–79 years. There was no difference by sex. The prevalence of VaMCI was 36.7%. VaD subjects had lower premorbid intellectual functioning and had 0.9 years less education than controls. The VaD and VaMCI groups did not differ from the no cognitive impairment group on any specific cerebrovascular risk factor, however overall those with impairment had a greater number of risk factors. They did not differ consistently on depression severity, homocysteine levels and neuroimaging parameters (atrophy, infarct volume and number of infarcts) except for an excess of white matter lesions on MRI and greater number of infarcts in the VaD and VaMCI groups. On a series of logistic regression analyses, stroke volume and premorbid function were significant determinants of cognitive impairment in stroke patients. Conclusion: Post-stroke dementia and MCI are common, especially in older individuals. Cerebrovascular risk factors are not independent risk factors for VaD, but stroke volume is a significant determinant of dementia. Premorbid functioning is a determinant of post- stroke impairment.
The Neurofilament Heavy Chain (NfHSMI35) in the Cerebrospinal Fluid Diagnosis of Alzheimer’s Disease
Authors: Brettschneider Johannes , Petzold Axel , Schöttle Daniel , Claus Annett , Riepe Matthias , Tumani Hayrettin
Published: February 2006

Background/Aims: Attempting to improve the cerebrospinal fluid (CSF) diagnosis of Alzheimer’s disease (AD), the neurofilament heavy chain isoform, NfHSMI35 was compared to other CSF markers [total tau, phospho-tau, amyloid beta 1–42 (Aβ42), the ratio of amyloid beta fragments Aβ42/Aβ40 (Aβ ratio)]. Methods: CSF levels were determined in patients with AD (n = 109), mild cognitive impairment (MCI, n = 25), frontotemporal dementia (n = 15), vascular dementia (VD, n = 41), and controls (n = 58). Results: CSF NfHSMI35 was elevated in AD and VD as compared to controls (p < 0.05). Total tau was higher in AD as compared to controls (p < 0.05). CSF phospho-tau was elevated in AD as compared to controls and VD (p < 0.05 each). CSF Aβ42 and Aβ ratios in AD were lower than in MCI and controls (p < 0.05 each). Conclusion: The diagnostic potential of NfHSMI35 is not superior to that of other CSF markers.
No Genetic Association between the Myeloperoxidase Gene –463 Polymorphism and Estrogen Receptor-α Gene Polymorphisms and Japanese Sporadic Alzheimer’s Disease
Authors: Usui Chie , Shibata Nobuto , Ohnuma Tohru , Higashi Shinji , Ohkubo Taku , Ueki Akira , Nagao Masatsugu , Arai Heii
Published: February 2006

Myeloperoxidase (MPO) presence has been demonstrated in microglia associated with senile plaques and contributes to Alzheimer’s disease (AD) pathology through oxidation-induced damage. MPO activity is normally higher in women than in men. Additionally, a functional biallelic (G/A) polymorphism in the promoter region (–463) of the MPO gene has been associated with a gender-specific risk factor for AD, but reports of this association have been inconsistent. Furthermore, estrogen is known to enhance MPO activity in myeloid cells and increases the amount of MPO in plasma. Recently, estrogen replacement therapy has been reported to reduce the risk of developing AD and to help maintain cognitive function in patients with AD. In the current study, we analyzed the MPO –463 polymorphism and two estrogen receptor-α polymorphisms in 205 Japanese sporadic AD patients and 92 controls. The results suggest that there is no significant difference in the genotypic frequencies and allelic frequencies of the MPO –463 polymorphism and the estrogen receptor-α polymorphisms between the Japanese sporadic AD group and the control group.
Pulmonary Function, Cognitive Impairment and Brain Atrophy in a Middle-Aged Community Sample
Authors: Sachdev P.S. , Anstey K.J. , Parslow R.A. , Wen W. , Maller J. , Kumar R. , Christensen H. , Jorm A.F.
Published: February 2006

Objective: To determine the relationship of lung function to brain anatomical parameters and cognitive function and to examine the mediating factors for any relationships. Methods: A random sub-sample of 469 persons (men = 252) aged 60–64 years from a larger community sample underwent brain magnetic resonance imaging scans and pulmonary function tests (forced vital capacity, FVC, forced expiratory volume in the first second, FEV1). Subjects were assessed for global cognitive function, episodic memory, working memory, information processing speed, fine motor dexterity and grip strength. The magnetic resonance imaging scans were analysed for overall brain atrophy, subcortical atrophy (ventricle-to-brain ratio, VBR), hippocampal volume, and white matter hyperintensity (WMH) volume. Results: FEV1 had a significant negative correlation with overall brain atrophy and VBR in men. The FEV1/FVC ratio had a significant correlation with WMHs in both men and women. In regression models that controlled for sex, age, height, level of activity, smoking, chronic respiratory disease and education, FEV1 and FVC were significant predictors of VBR but no other structural brain measure. Pulmonary function was also significantly related to information processing speed and fine motor dexterity. Male subjects with chronic respiratory disease had more deep WMHs. Path analyses to examine if structural measures mediated between lung function and cognition, and whether markers of inflammation and oxidative stress or cortisol mediated between lung function and brain measures were negative. Conclusions: Decreased lung function is related to poorer cognitive function and increased subcortical atrophy in mid-adult life. Presence of chronic respiratory disease may be related to deep WMHs in men.
Chemotherapy for Colorectal Cancer
Authors: Goyle Sandeep , Maraveyas Anthony
Published: February 2006

Colorectal cancer is the most commonly diagnosed cancer in the EU. Various randomised studies have shown a survival benefit with chemotherapy in the adjuvant setting. Adjuvant chemotherapy with 5-fluorouracil/folinic acid (5FU/FA) for 6 months after curatively resected node-positive colon cancer has become the standard practice. However, controversy still exists regarding the optimal regimen and whether to treat node-negative patients. The latest QUASAR trial results seem to strengthen the argument in favour of adjuvant treatment of Dukes B cancer. Patients with Dukes B tumours and any adverse prognostic indicator should be given the benefit of adjuvant therapy. A number of novel agents (oxaliplatin, irinotecan) showing activity in advanced disease are currently being evaluated in the adjuvant setting. A patient with metastatic colorectal cancer should today be expected to have a median survival of 18–20 months compared to that of 11–14 months only a few years ago. 5FU/FA has been the mainstay of therapy for metastatic colorectal cancer for over 40 years and confers a survival benefit over supportive care. The response rate of 5FU is improved by modulation with FA or by continuous infusional regimens (currently the best expected response rate is around 20–25%). As per the recent National Institute for Clinical Excellence guidelines, the oral agents capecitabine or tegafur with uracil (in combination with FA) can be used as first-line treatment in metastatic colorectal cancer and, although their response rate has not been directly compared to infusional 5FU, survival is unlikely to be inferior. Newer chemotherapeutic agents like irinotecan and oxaliplatin are now entering regular usage due to improved response rates (around 50% in 5FU/FA-containing doublets) and survival. Irinotecan monotherapy is second-line treatment approved by the National Institute for Clinical Excellence, although sequential infusional 5FU/FA irinotecan to infusional 5FU/FA oxaliplatin may convey the best survival with the least side effects. The position of combination chemotherapy before (to downstage) or after metastasectomy (usually from the liver) is still a topic of heated debate. Other routes (intrahepatic, intraperitoneal) are still to be proven and not recommendable outside the trial setting. The latest results of chemotherapy combinations with biological treatments (bevacuzimab and cetuximab) have been very promising indeed. Further improvements in survival, response and quality of life are expected.
Reversal of Hartmann’s Procedure after Surgery for Complications of Diverticular Disease of the Sigmoid Colon Is Safe and Possible in Most Patients
Authors: Oomen J.L.T. , Cuesta M.A. , Engel A.F.
Published: February 2006

Background: Although evidence is growing that most patients who need an operation for diverticular disease of the sigmoid colon can be treated by a single-stage procedure, a two-stage procedure will still be necessary in some patients because of significant sepsis or technical difficulties. The outcomes of 65 patients who underwent secondary restoration after a Hartmann procedure for complicated diverticulitis were studied and the factors leading to complications and mortality were identified. Patients and Methods: Of 91 patients, in a consecutive 12-year period, whose primary operation was a Hartmann procedure, 72 survived longer than 3 months after discharge. Sixty-five underwent an attempted reversal of the Hartmann procedure. The POSSUM scores were calculated in all patients as well as the morbidity and mortality rates. Results: In 63 (96.9%) patients the bowel continuity could be restored with a morbidity of 38.5% and a mortality of 3.1%. The POSSUM and p-POSSUM scores adequately predicted the mortality in this series. Conclusion: This series shows that when surgical treatment for complicated diverticular disease of the sigmoid colon is necessary, the Hartmann procedure is still a valid indication. In a high percentage of patients the Hartmann procedure could be restored with a low mortality.
First Results after Introduction of the Four-Armed da Vinci Surgical System in Fully Robotic Laparoscopic Cholecystectomy
Authors: Heemskerk Jeroen , van Dam Ronald , van Gemert Wim G. , Beets Gerard L. , Greve Jan Willem M. , Jacobs Michael J.H.M. , Bouvy Nicole D.
Published: February 2006

Background: Laparoscopic cholecystectomy offers less post-operative pain, less complications, and faster recovery compared with open cholecystectomy. However, laparoscopic surgery can be demanding because of several technical drawbacks. Robotic surgery allows dexterity skills to be performed faster and shortens the learning curve, possibly leading to faster and safer laparoscopic surgery. Methods: In this paper, we report the results of our first 12 cases of fully robotic laparoscopic cholecystectomy using the da Vinci Surgical System, comparing them with 12 cases of conventional laparoscopic cholecystectomy. Using a fourth arm in robotic laparoscopy enables the surgeon to perform surgery without the use of a tableside assistant, leading to non-tiring, tremble-free assistance and reducing salary costs. Primary end points are operating time and costs. Secondary end points are operative complications and duration of admission. Results: Fully robotic cholecystectomy was completed in all 12 cases without increased complication rate and without conversions. However, robotic assistance results in an increased overall operating room stay of 31 min and increased costs of EUR 1,180.62. Conclusion: Fully robotic laparoscopic cholecystectomy is safe and feasible but seems more expensive and time consuming at this moment.
Laparoscopic Staging in Gallbladder Cancer
Authors: Agrawal Shaleen , Sonawane Rajendra N. , Behari Anu , Kumar Ashok , Sikora Sadiq S. , Saxena Rajan , Kapoor Vinay K.
Published: February 2006

Purpose: Laparoscopy is beneficial in the staging of pancreatic and upper gastrointestinal malignancies but its role in gallbladder cancer has not been investigated. We evaluated the role of laparoscopy in the staging of gallbladder cancer. Methods: From 1989 through 2001, 91 patients with gallbladder cancer, without any evidence of metastatic disease on imaging (ultrasound and/or computed tomographic scan), underwent staging laparoscopy. Peritoneal and surface liver metastases were looked for and assessment of local spread was done if possible. Assessment was based on visual impression and biopsies were not obtained routinely. Results: At laparoscopy, 34 (37%) patients had disseminated disease in the form of liver and/or peritoneal deposits; no further surgery was performed in 29 of these patients while 5 patients underwent surgical bypass procedures. Liver metastases were missed at laparoscopy in 2 patients and were subsequently found at laparotomy. Assessment of the gallbladder mass was possible in 33 (36%) patients, 6 of these were found to have extensive local disease and did not undergo any further surgery. Laparoscopic staging, thus avoided further surgery in 35 (38%) patients. Of the 51 patients without metastatic disease, who underwent laparotomy, 11 were found to have nonresectable locally advanced disease while 1 had liver metastases, which were missed at laparoscopy; 7 underwent bypass procedures only; 21 underwent simple cholecystectomy and extended cholecystectomy was done in 11 patients. The resectability rate (number of resections/operations) in patients undergoing laparoscopic staging was 57% (32/56) as compared with 43% (142/328) in those who did not undergo laparoscopy. Conclusions: Staging laparoscopy in patients with gallbladder cancer detected liver and peritoneal metastases that were missed on imaging. It reduced the number of unnecessary surgical explorations and improved the resectability rate.
New Method for Phosphate Kinetics Estimation during Hemodialysis and On-Line Hemodiafiltration with Endogenous Reinfusion
Authors: Bolasco P. , Ghezzi P.M. , Ferrara R. , Cogoni G. , Cadinu F. , Casu D. , Murtas S.
Published: February 2006

Aim: The purpose of this study was to optimize the operative and analytical methodologies to a more exact determination of intradialytic kinetics of the phosphates (P) tested in hemodialysis (HD) and in on-line hemodiafiltration with endogenous reinfusion (HFR – Hemo Filtrate Reinfusion). Methods: The mass balance measurements of urea and P were carried out in 18 clinically stable HD patients. The effective blood flow (Qb) was measured with a Transonic® monitor. The plasma was deproteinized with 10% trichloroacetic acid to prevent breakdown of the proteins and the consequent pseudohyperphosphatemia. Subsequently the supernatant containing the ultrafiltrable phosphates was made to react with a solution of ammonium molybdate for a spectrophotometric reading. Results: The mean urea mass transfer in HD was 16.9 g/session and in HFR 15.4 g/session. The mean P mass transfer in HD was 726 mg/session and in HFR 679 mg/session. Nevertheless, in HFR a significant difference was verified between the clearances of P, between the plasma water side (122.4 ± 30.8 ml/min) and the dialysate side (105.9 ± 19.4 ml/min). Conclusion: As far as the P mass transfer is concerned, the data obtained is able to be superimposed with that described in the literature during HD, while in HFR it is possible to hypothesize a high efficiency, thanks to an increased output of P in relation to the phenomenon of adsorption which, although is limited, contributes to the transfer of the total mass. Based on this study and re-examining the literature on P kinetics, there is space for methodological improvement both on the operating front with careful determination of the effective Qb, and on the chemical front overcoming the inaccuracy of automatic analyzers in determining the plasma P owing to possible overestimation of phosphatemia and poor sensitivity in measuring the lower levels of P present in the dialysate and/or ultrafiltrate.
Plasma Prohepcidin Positively Correlates with Hematocrit in Chronic Hemodialysis Patients
Authors: Hsu Shih-Ping , Chiang Chih-Kang , Chien Chiang-Ting , Hung Kuan-Yu
Published: February 2006

Background/Aims: Experimental studies have demonstrated interleukin-6 and iron load induce expression of hepcidin (an iron regulatory peptide), whereas anemia and erythropoietin (EPO) suppress its expression. We are the first to explore the relationships of plasma prohepcidin (the pro-hormone of hepcidin) in patients undergoing chronic hemodialysis (HD). Methods: We enrolled 71 chronic HD patients. During the preceding 3 months before enrollment, they all had steady weekly levels of haematocrit (Hct) and fixed subcutaneous doses of recombinant human EPO. Plasma levels of prohepcidin, proinflammatory cytokines, and EPO were determined by ELISA kits. Results: Of the patients, prohepcidin levels correlated positively with Hct, and negatively with interleukin-6 and EPO. Examined by a multivariate lineal regression method, we found Hct was the only significant predictor of plasma prohepcidin level. However, prohepcidin had no significant correlation with iron profiles. Conclusion: Our findings suggest prohepcidin expression in chronic HD patients might be positively regulated by Hct.
CT and MRI of Lung Cancer
Authors: Laurent François , Montaudon Michel , Corneloup O.
Published: February 2006

Computed tomography (CT) is still the cornerstone of imaging studies in the preoperative staging and post- therapeutic evaluation of lung cancer. The most recent developments in multidetector technology have dramatically improved the temporal and spatial resolution of CT. In the mean time, magnetic resonance imaging (MRI) has not become a routine examination in lung imaging and is today only used as a problem-solving tool in patients in whom CT remains equivocal. This article will describe the current tools developed in the multidetector CT era for evaluating the lung, and state-of-the-art MR examination of the chest. Then, the role of CT and MRI in nodule detection, the distinction between benign and malignant nodules, and the benefit of CT and MRI in the staging and post-therapeutic evaluation of lung cancer will be covered.
A model for the harmonisation of test results of different quantitative D-dimer methods
Authors: Haverkate Frits , Kluft Cornelis , de Moerloose Philippe , Verbruggen Bert , Spannagl Michael , Meijer Piet
Published: February 2006

The numerical test results of different D-dimer assays vary widely. Because of the complexity of the analyte of target as well as the variability in specificity of different D-dimer assays, only harmonisation of the test results seems to be feasible. The use of a single conversion factor does not take into account for several methods the lack of commutability between test results and consensus values at different D-dimer levels. This is probably related to the mutually different response of methods to high and low levels. We therefore designed a harmonisation model based on the transformation of a method-specific regression line to a reference regression line. We used the data for the measurement of a set of plasma samples with different D-dimer levels by 353 different laboratories using 7 of the most frequently used quantitative D-dimer methods. For each method we calculated the method-specific consensus value for each sample. The overall median value was also estimated. Per method linear regression was applied throughout the method-specific consensus values using the amount of patient pooled plasma added to the different plasma samples as the independent variable. The line through the overall median values of all 7 methods was used as the reference line. Harmonisation between the methods was obtained by transformation of the method-specific regression line to the reference line. This harmonisation resulted in a reduction of the variability between the method-specific consensus values from about 75% to about 5.5%. Clinical validation of this concept had shown significant improvement of the test result comparability. We conclude that this model isa feasible approach in the harmonisation of D-dimer methods. If the harmonisation procedure is included in the calibration procedure by the manufacturers, customers will automatically obtain harmonised test results.
Evaluation of the pro-angiogenic effect of factor XIII in heterotopic mouse heart allografts and FXIII-deficient mice
Authors: Dardik Rima , Leor Jonathan , Skutelsky Ehud , Castel David , Holbova Radka , Schiby Ginette , Shaish Aviv , Dickneite Gerhard , Loscalzo Joseph , Inbal Aida
Published: February 2006

Thrombin-activated Factor XIII (FXIIIa),a plasma transglutaminase, stabilizes fibrin clots by crosslinking fibrin chains. FXIIIa was previously shown by us to exhibit proangiogenic activity associated with downregulation of thrombospondin-1, phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR-2), and upregulation of c-Jun. In the current study, we evaluated the proangiogenic effect of FXIIIa in two murine models: a neonatal heterotopic cardiac allograft model in normal mice, and a Matrigel plug model in FXIII-deficient mice. In the neonatal cardiac allograft model, the number of new vessels as well as graft viability (contractile performance) was significantly higher in FXIIIa-injected animals than in controls. A significant increase in the level of c-Jun mRNA and a significant decrease in the level of TSP-1 mRNA were observed in heart allografts treated with FXIIIa. A marked decrease in TSP-1 protein expression was observed within the endothelial cells of hearts treated with FXIIIa. In the Matrigel plug model, FXIII-deficient mice showed a significantly decreased number of new vessels compared to that of the control mice,and the number of vessels almost reached normal levels following addition of FXIIIa. The results of this study provide substantial in vivo evidence for the proangiogenic activity of FXIIIa.
Thrombelastography for the monitoring of lipopolysaccharide induced activation of coagulation
Authors: Zacharowski Paula , Zacharowski Kai , Sucker Christoph , Hartmann Matthias
Published: February 2006

During Gram-negative sepsis, lipopolysaccharide (LPS) activates toll-like receptor (TLR) 4 and induces complex responses of immune system and haemostasis. In the present study we investigated whether thrombelastography is suitable to monitor the LPS-induced activation of coagulation. Whole blood samples from healthy volunteers were incubated with LPS for various in-cubation periods (0–5 hrs), thereafter rotation thrombelastography was performed. Incubation of whole blood (≥ 3 h) with LPS markedly reduced clotting time; after 5 hrs the variable was reduced from 459 ± 39 sec to 80 ± 20 sec while the other thrombelastography variables (angle α, clot formation time, maximal clot formation) remained unaltered. EC50 of the LPSeffect on whole blood clotting time was 18 µg/ml.In isolated leu kocytes, diluted in platelet poor plasma, far lower LPS-concentrations were effective: 10 ng/ml LPS reduced clotting time from 439 ± 68 sec to 200± 56 sec. Experiments with the protein synthesis inhibitor cycloheximide and active site-inhibited factor VIIa revealed that LPS exerts its effects via the synthesis of tissue factor.Addition of tissue factor to whole blood samples revealed that a concentration of 100 fmol/l can be detected using thrombelastography. In whole blood samples the tissue factor concentration induced by LPS amounted up to 12 pmol/l. In summary, thrombelastography proved to bea sensitive and reliable tool for the determination of LPS-induced tissue factor mediated activation of haemostasis in whole blood samples.
Autosomal dominant thrombocytopenias with reduced expression of glycoprotein Ia
Authors: Noris Patrizia , Guidetti Gianni , Conti Valeria , Ceresa Iride , Di Pumpo Michele , Pecci Alessandro , Torti Mauro , Savoia Anna , Balduini Carlo
Published: February 2006

We have recently studieda case series of 46 unrelated patients with inherited thrombocytopenias and identified 18 cases that did not fit any known platelet disorder. In two unrelated families, a mild thrombocytopenia with normal platelet size was transmitted in an autosomal dominant fashion. Bleeding time was prolonged in 5 investigated patients. In all of them, flow cytometry and SDS-PAGE of platelet glycoproteins (GP) showed a reduced content of GPIa, a subunit of the GPIa-IIa complex (also known as integrin α2β1) that is a major collagen receptor on platelets.All other membrane GPs were within the normal range. GPIa deficiency was associated with severely reduced in vitro platelet adhesion to molecules known to interact selectively with GPIa. In vitro platelet aggregation was normal in all subjects, except for a suboptimal platelet response to fibrillar collagen in two patients.A mild defect of α-granules was observed in all affected subjects. No mutation was identified in the genes encoding for GPIa or GPIIa. Since no other similar cases have been reported in the literature, we suggest that an autosomal dominant thrombocytopenia associated with GPIa deficiency and α-granule defect represents a new form of inherited thrombocytopenia.
Truncated and microparticle-free soluble tissue factor bound to peripheral monocytes preferentially activate factor VII
Authors: Niewiarowski Stefan , Colman Robert , Khan Mohammad , Hattori Takashi , Edmunds L.
Published: February 2006

Soluble plasma tissue factor (TF) circulates in picomolar concentrations in healthy individuals and increases in a wide spectrum of diseases. This study tests the hypothesis that both truncatedTF (rsTF) or soluble plasmaTF (pTF) in low concentration combine with monocytes or platelets to convert factorVII (fVII) to fVIIa. Both rsTF (33 kDa) and pTF (47 kDa), obtained from pericardial wounds of patients having cardiac surgery using cardiopulmonary bypass (CPB), were studied in association with blood cells and TF-bearing microparticles. Tissue factor was measured by ELISA. RsTF binds to erythrocytes, platelets, mononuclear cells and polymorphoneutrophils. The rate of fVII conversion with rsTF (1–103 nM) is highest with mononuclear cells, less with platelets, minimal with polymorphoneutrophils and undetectable with erythrocytes. Either stimulated or unstimulated mononuclear cells or platelets in the presence of 3.5 pM rsTF or pTF convert fVII (10 nM) to fVIIa, but the amounts of fVIIa produced differ. When leukocytes or platelets are absent, microparticles associated with 3.5 pM TF antigen derived from pericardial wound plasma do not activate fVII. Stimulated mononuclear cells convert nearly all available fVII (10 nM) to fVIIa with 3.5 nM pTF; unstimulated mononuclear cells convert small amounts of fVII with 1 pM rsTF. In all comparisons mononuclear cells more efficiently convert fVII to fVIIa than do platelets. This study shows that stimulated mononuclear cells provide the most efficient platform for activation of rsTF or pTF at low concentrations of TF antigen.
Direct interaction of the kringle domain of urokinase-type plasminogen activator (uPA) and integrin αvβ3 induces signal transduction and enhances plasminogen activation
Authors: Tarui Takehiko , Akakura Nobuaki , Majumdar Mousumi , Andronicos Nicholas , Takagi Junichi , Mazar Andrew , Bdeir Khalil , Kuo Alice , Yarovoi Serge , Cines Douglas , Takada Yoshikazu
Published: February 2006

It has been questioned whether there are receptors for urokinase-type plasminogen activator (uPA) that facilitate plasminogen activation other than the high affinity uPA receptor (uPAR/CD87) since studies of uPAR knockout mice did not support a major role of uPAR in plasminogen activation. uPA also promotes cell adhesion, chemotaxis, and proliferation besides plasminogen activation. These uPA-induced signaling events are not mediated by uPAR,but mediated by unidentified,lower-affinity receptors for the uPA kringle.We found that uPA binds specifically to integrin αvβ3 on CHO cells depleted of uPAR. The binding of uPA to αvβ3 required the uPA kringle domain. The isolated uPA kringle domain binds specifically to purified,recombinant soluble, and cell surface αvβ3, and other integrins (α4β1 and α9β1), and induced migration of CHO cells in an αvβ3-dependent manner. The binding of the uPA kringle to αvβ3 and uPA kringle-induced αvβ3-dependent cell migration were blocked by homologous plasminogen kringles 1-3 or 1-4 (angiostatin),a known integrin antagonist. We studied whether the binding of uPA to integrin αvβ3 through the kringle domain plays a role in plasminogen activation. On CHO cell depleted of uPAR, uPA enhanced plasminogen activation in a kringle and αvβ3-dependent manner.Endothelial cells bound to and migrated on uPA and uPA kringle in an αvβ3-dependent manner. These results suggest that uPA binding to integrins through the kringle domain plays an important role in both plasminogen activation and uPA-induced intracellular signaling. The uPA kringle-integrin interaction may represent a novel therapeutic target for cancer, inflammation, and vascular remodeling.
Myxoma viral serpin, Serp-1, a unique interceptor of coagulation and innate immune pathways
Authors: Viswanathan Kasinath , Liu Liying , Vaziri Sepideh , Dai Erbin , Richardson Jakob , Togonu-Bickersteth Babajide , Vatsya Pracha , Christov Alexander , Lucas Alexandra
Published: February 2006

Serpins maintain haemostasis through regulation of serine proteinases in the thrombotic and thrombolytic pathways. Viruses encode serpins that can alter thrombotic and thrombolytic responses producing, in some cases, disseminated intravascular coagulation (DIC). However, it has not been precisely defined how viral serpins induce these profound responses. The rabbit myxoma viral serpin, Serp-1 inhibits urokinase- and tissue-type plasminogen activators (uPA and tPA), plasmin and factor Xa in vitro and exhibits remarkable anti-inflammatory activity in various animal models. The effects of Serp-1 on activation of human platelets, endothelial cells, monocytes and T cells that mediate thrombosis and innate immune responses were therefore examined. We found that Serp-1 attenuated platelet and mononuclear cell adhesion to fibronectin and collagen. Serp-1 similarly inhibited monocyte migration into the peritoneum. Serp-1 inhibition of monocyte migration was lost in uPA receptor (uPAR) deficient mice. Serp-1 bound to the plasma membrane surface and altered uPA activation of endothelial cells (p=0.001), thrombin activation of platelets (p=0.021) and phorbol ester activation of endothelial (p=0.047), monocyte (p=0.011) and Jurkat T cells (p=0.012) as measured by intracellular calcium. Modulation of cellular activation was confirmed by membrane fluidity analysis. Microarray analysis of Serp-1 treated endothelial cells revealed alterations in Inositol 1,4,5-triphosphate receptor type II (ITPR2) a calcium-regulating gene. This study demonstrates the unique capacity ofa viral serpin, Serp-1 to modify adhesion, activation, gene expression and calcium homeostasis in a wide range of cells that regulate coagulation and inflammation. Endothelial cells potentially represent a pivotal regulatory point for Serp-1 anti-inflammatory activity.
The ability of different forms of heparins to suppress P-selectin function in vitro correlates to their inhibitory capacity on bloodborne metastasis in vivo
Authors: Ludwig Ralf , Alban Susanne , Bistrian Roxana , Boehncke Wolf-Henning , Kaufmann Roland , Henschler Reinhard , Gille Jens
Published: February 2006

Ample evidence suggests that many of the in vivo anti-metastatic effects by heparins reflect their actions on P-selectin-mediated binding. We hypothesized that the ability of widely used heparins and derivatives to interfere with P-selectin-dependent tumour cell interactions under flow in vitro could be used to identify anticoagulants with advanced inhibitory functions on experimental blood-borne metastasis in vivo. To test this assumption, the impact of unfractionated heparin, the low-molecular-weight heparins (LMWH) nadroparin and enoxaparin, and the synthetic pentasaccharide fondaparinux on P-selectin-dependent tumour interactions in vitro and metastasis formation in vivo were evaluated. Our data revealed that these commonly used anticoagulants widely differ in their potential to interfere with P-selectinmediated cell binding. Importantly, the superior inhibitory capacity on P-selectin function of unfractionated heparin and LMWH nadroparin as opposed to LMWH enoxaparin and synthetic heparin pentasaccharide fondaparinux strongly correlated to the inhibitory potency of each in inhibiting experimental lung metastasis in vivo. Hence, P-selectin inhibition may constitute a valuable feature to identify anticoagulants that are suitable for anticancer therapy.
Vascular risk factors in sudden hearing loss
Authors: Rudack Claudia , Langer Claus , Stoll Wolfgang , Rust Stephan , Walter Michael
Published: February 2006

Low density lipoprotein (LDL) and fibrinogen apheresis was recently reported to be an effective therapy in sudden hearing loss (SHL). In this study, we investigated whether lipoprotein and/or fibrinogen plasma concentrations, related gene polymorphisms and other cardiovascular risk factors are also risk factors for SHL.

Total cholesterol, HDL and LDL cholesterol plasma concentrations, fibrinogen levels, and two functionally relevant fibrinogen polymorphisms were determined in 142 consecutive patients and in 84 age- and sex-matched control subjects of the same ethnic background, using routine laboratory methods and PCR analysis. In addition, we determined the platelet glycoprotein Ia (GPIa) C807T polymorphism, which was recently proposed to be a genetic risk factor for SHL, and we compared the patients’ and controls’ clinical characteristics.

Total and LDL cholesterol concentrations were not different between patients and controls. Fibrinogen plasma levels were significantly increased in SHL patients (260±57 vs. 239±110 mg/dl, p=0.002). However, fibrinogen was not related to SHL in multivariate analysis,and none of the investigated fibrinogen polymorphisms was associated with SHL. By contrast,T allele carriers of the GPIa 807 polymorphic site had an increased risk to develop SHL (OR 1.81) and were more likely not to recover from SHL, compared to C allele carriers (OR 3.0). Moreover, significantly more SHL patients were current smokers (56.3% vs. 19.3% in the control group, p<0.0001).

In conclusion, there is a partial overlap between classical coronary risk factors and risk factors for SHL. Hypercholesterolemia and hypoalphalipoproteinemia (low HDL cholesterol levels) are apparently no major risk factors for SHL, whereas the GPIa C807T polymorphism, elevated fibrinogen levels, and smoking are associated with an increased risk for SHL.Altogether these findings suggest a vascular involvement in the pathogenesis of SHL and may have important implications for the development of therapeutic and preventive strategies.
C-reactive protein, interleukin-6 and tumor necrosis factor alpha as predictors of incident coronary and cardiovascular events and total mortality
Authors: Tuomisto Karolina , Jousilahti Pekka , Sundvall Jouko , Pajunen Pia , Salomaa Veikko
Published: February 2006

Previous studies have shown an association between serum C-reactive protein (CRP) and cardiovascular disease (CVD) risk. The roles of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNFα) are less well established. The aim of the present study was to analyze the associations of CRP, IL-6 and TNFα with incident coronary heart disease (CHD) events, CVD events, and total mortality. A random population sample, including men and women aged 25–64 years was examined in Finland in 1992.The sample size was 7,927 and 6,051 (76%) participated. The cohort was followed up until the end of 2001. During the follow-up, 151 incident CHD events, 205 CVD events and 183 deaths from any cause were observed. A stratified random subsample (n=313) was used as the comparison group. After adjustment for conventional CVD risk factors, CRP showeda significant association with CHD risk in men (HR=2.39, 1.08–5.28, comparing fourth quartile to the first quartile).This association remained significant after further adjustment for TNFα. TNFα also was a significant predictor of CHD among men, but the association was nonlinear (HR=2.21, 1.18–4.14 comparing the three upper quartiles to the first quartile). Further adjustment for CRP did not change this association substantially. Both CRP and TNFα predicted also all CVD events and total mortality among men. Among women the findings were nonsignificant. In conclusion, CRP andTNFα were significant, independent predictors of CHD and CVD events and total mortality among men. These findings provide further support to the important role of inflammation in the pathogenesis of CVD.
Genetic influences on fibrinogen, tissue plasminogen activatorantigen and von Willebrand factor in males and females
Authors: de Geus Eco , Kluft Cornelis , Meijer Piet , van Doornen Lorenz , Boomsma Dorret , Snieder Harold , de Lange Marlies
Published: February 2006

Differences in genetic influence on death from CHD between males and females have been reported. Haemostatic factors have consistently been associated with risk for coronary heart disease (CHD), but sex differences in genetic architecture have not been studied. This study in middle-aged twins investigates whether there are sex differences in means and in genetic and/ or environmental variance components of haemostatic risk factors for CHD. A total of 93 monozygotic twin pairs (44 male and 49 female) and 116 dizygotic twin pairs (36 male, 40 female and 40 opposite sex) were available for this study. Structural equation modelling was used to estimate the relative influence of genetic and environmental factors on variation in levels of fibrinogen, tissue plasminogen activator (tPA) antigen and von Willebrand factor (vWF). Mean levels of tPA and vWF increased with age. Oral contraceptive pill (OCP) and menopause had significant influences on levels of fibrinogen and tPA. Genetic influences explained 39, 66 and 72% of the variation in levels of fibrinogen, tPA and vWF, respectively. No quantitative or qualitative differences of genetic influences on haemostatic levels were seen between males and females. Haemostatic factors may account fora significant part of the genetic risk for cardiovascular disease. No difference in genetic architecture for levels of fibrinogen, tPA or vWF was observed between males and females.
Mutations in coagulation factor XIII A gene in eight unrelated Indians
Authors: Jayandharan Giridhara , Viswabandya Auro , Baidya Shoma , Nair Sukesh , George Biju , Mathews Vikram , Chandy Mammen , Srivastava Alok
Published: February 2006

Factor XIII deficiency is a rare autosomal (1:2,000,000) recessive disorder of blood coagulation usually attributed to mutations in the coagulation factor XIII (FXIII) A gene. We have studied the molecular basis of FXIII deficiency in eight unrelated South Indian patients. Their diagnosis was based on clinical history, normal plasma clotting times and increased solubility of fibrin clot in5 mol/l urea. Genomic DNA was screened for FXIII A gene defects by a novel PCR and CSGE strategy. Mutations were identified in all these patients. Five of these were novel mutations occurring in four patients. These included a novel c.210T>G transversion in homozygosity in exon 3 predicting a Tyr69X in the beta-sandwich domain in one patient. Another patient was compound heterozygote for a novel c.791C>T transition predicting a Ser263Phe in the core domain and a novel c.2045–1G>A transition at the acceptor splice junction of in tron 14. Two novel frame shifts were also identified in two patients in a homozygous condition. One of them resulted from a single base ‘G’ duplication (c.892_895dupG) at codons Ser290/Ala291fs affecting the core domain and the other was due to a single base ‘A’ duplication (c.1642_1644dupA) and at codonTyr547fs affecting barrel-1 domain. The remaining four patients had the previously reported Arg260His, Ser413Leu, and Val414Phe (n = 2) missense mutations in the core domain. The novel mutations identified were considered to be disease causative by studying the nature of mutation, the degree of conservation of the mutated aminoacid among transglutaminases of different species and by molecular modeling. Apart from describing a significant number of novel mutations, this report is the first study from Southern India to describe FXIII A gene mutations.