bluuebunny/crossref_metadata_2025 huggingface dataset:
Family-Based Association Tests with Longitudinal Measurements: Handling Missing Data
Authors: Ding Xiao , Laird Nan
Published: April 2009

Several family-based approaches have been previously proposed to enhance the power for testing genetic association when the traits are measured longitudinally or repeatedly. In this paper, we show that some of these FBAT approaches can be easily extended to accommodate incomplete data and remain unbiased tests. We also show that because of the nature of FBAT approaches, we can impute the missing phenotypes without biasing our tests and achieve higher power. We propose two imputation techniques based on E-M algorithm and the conditional mean model, respectively. Through simulation studies, these two imputation techniques are shown to have correct false positive rate and generally achieve higher power than complete case analysis or simple mean-imputation. Application of these approaches for testing an association between Body Mass Index and a previously reported candidate SNP confirms our results.
Comparison of Methods for Combining Case-Control and Family-Based Association Studies
Authors: Glaser Beate , Holmans Peter
Published: April 2009

Objectives: Combining the analysis of family-based samples with unrelated individuals can enhance the power of genetic association studies. Various combined analysis techniques have been recently developed; as yet, there have been no comparisons of their power, or robustness to confounding factors. We investigated empirically the power of up to six combined methods using simulated samples of trios and unrelated cases/controls (TDTCC), trios and unrelated controls (TDTC), and affected sibpairs with parents and unrelated cases/controls (ASPFCC). Methods: We simulated multiplicative, dominant and recessive models with varying risk parameters in single samples. Additionally, we studied false-positive rates and investigated, if possible, the coverage of the true genetic effect (TDTCC). Results/Conclusions: Under the TDTCC design, we identified four approaches with equivalent power and false-positive rates. Combined statistics were more powerful than single-sample statistics or a pooled χ2-statistic when risk parameters were similar in single samples. Adding parental information to the CC part of the joint likelihood increased the power of generalised logistic regression under the TDTC but not the TDTCC scenario. Formal testing of differences between risk parameters in subsamples was the most sensitive approach to avoid confounding in combined analysis. Non-parametric analysis based on Monte-Carlo testing showed the highest power for ASPFCC samples.
The Effect of Inbreeding on the Distribution of Compound Heterozygotes: A Lesson from Lipase H Mutations in Autosomal Recessive Woolly Hair/Hypotrichosis
Authors: Petukhova Lynn , Shimomura Yutaka , Wajid Muhammad , Gorroochurn Prakash , Hodge Susan E. , Christiano Angela M.
Published: April 2009

Autozygosity mapping in consanguineous families has proven to be a powerful method for identifying recessive disease genes. Using this technique with whole genome SNP data generated from low density mapping arrays, we previously identified two genes that underlie autosomal recessive woolly hair (ARWH/hypotrichosis; OMIM278150), specifically P2RY5 and Lipase H (LIPH). In the current study, we sought to identify a novel disease locus for ARWH/hypotrichosis by analyzing two large consanguineous families from Pakistan who had initially been excluded for mutations at either of these disease loci by haplotype analysis with microsatellite markers. A genome-wide analysis of 10 members from each of the two families failed to identify significant regions of autozygosity or linkage. Upon genotyping an additional 10 family members in one of the families, parametric linkage analysis identified a region on chromosome 3q27 with evidence for linkage (Z = 2.5). Surprisingly, this region contains the LIPH gene. Microsatellite markers located within the LIPH gene were used for haplotype analysis and demonstrated that not one, but two haplotypes were segregating with the phenotype in each of these families. DNA sequencing identified two distinct LIPH mutations (280_369dup90 and 659_660delTA). Each affected individual (n = 38) was either homozygous for one mutation (n = 7 and 16 respectively), or compound heterozygous (n = 15). A review of the literature identified several reports of compound heterozygotes in consanguineous families. Prompted by this finding, we derived the probability that a patient affected with a recessive disease is carrying two mutations at the disease locus. We suggest that the validity of the IBD assumption may be challenged in large consanguineous families.
Analysis of Fifty-Six Cochlear Implant Device Failures
Authors: Gosepath Jan , Lippert Karl , Keilmann Annerose , Mann Wolf J.
Published: April 2009

Objective: Our aim was to present a failure analysis after cochlear implant revision surgery in a large series of children and adults and to assess the outcome and audiologic performance. Methods: Fifty-six cochlear implant failures that occurred in 422 devices implanted between 1990 and 2007 at the Department of Otolaryngology, Head and Neck Surgery at the University of Mainz, Germany, were retrospectively analyzed. The causes of failure were reviewed evaluating the individual history, telemetric and intraoperative findings and manufacturer’s investigation reports. Results: We performed 56 surgical revisions in a series of 422 consecutive implants (overall revision rate: 13.27%). The most frequent causes for revision were hard failures (58.9%), most commonly caused by traumatic impact (37.5%), especially in the pediatric population. Soft failures were less frequent (21.4%). Surgical reimplantations, although challenging in some cases, were performed without complications and with an electrode insertion depth comparable to that at the time of the initial implantation in all patients. The average audiologic performance improved by 2.4 dB in pure-tone perception levels after reimplantation. Conclusion: The cochlear implant failure rates vary between children and adults as well as between different implant manufactures. However, cochlear reimplantation is safe with excellent and predictable results in audiologic performance.
Echinacea purpurea Polysaccharide Reduces the Latency Rate in Herpes Simplex Virus Type-1 Infections
Authors: Ghaemi Amir , Soleimanjahi Hoorieh , Gill Pooria , Arefian Ehsan , Soudi Sara , Hassan Zuhair
Published: April 2009

Objective: During the latency period of herpes simplex virus type-1 (HSV-1), the virus can occasionally reactivate, travel back to the eye and cause recurrent ocular disease. As this condition arises from the ability of HSV-1 to produce a dormant infection, effective medication to prevent the virus enter a latent state should prevent it. In this study, we applied Echinacea polysaccharide (EP) fraction as prophylactic mediator for latency prevention. Methods: In order to investigate the protective properties of EP, we evaluated its immunostimulatory functions on different immune aspects that play important roles in latency prevention (particularly IFN-γ as one of the main indicators of cellular immunity and latency). Finally, we assessed establishment of latency by detection of thymidine kinase gene in trigeminal ganglia of BALB/c mice. Results: We demonstrated that EP promotes immune response, leading to a reduced latency rate, and it has a promising effect on latency prevention. Conclusion: EP was able to exert an antiviral action on the development of recurrent HSV-1 disease when supplied prior to infection.
Ectopic Pregnancy Rates after Frozen versus Fresh Embryo Transfer: A Meta-Analysis
Authors: Jee Byung Chul , Suh Chang Suk , Kim Seok Hyun
Published: April 2009

Background/Aims: The aim of this meta-analysis was to determine whether frozen embryo transfer (ET) increases ectopic pregnancy (EP) rate compared with fresh ET. Methods: A meta-analysis was performed of data from seven comparative studies including 13,059 pregnancies that resulted from nondonor in vitro fertilization cycles. Results: The EP rate was 2.31% (49/2,125 pregnancies) for frozen ET and 1.48% (162/10,934 pregnancies) for fresh ET. These rates were statistically not different when assessed either by random (OR 1.66, 95% CI 0.62–4.41) or fixed effect model (OR 1.17, 95% CI 0.84–1.63). Conclusions: The combined data presented in this meta-analysis do not support an increased risk of EP following frozen ET compared with fresh ET. However, as there was a substantial heterogeneity among the studies analyzed, the authors consider that further well-designed studies controlling for several potential biases which could affect the EP risk should be conducted.
Lymph Nodes in Hidradenitis Suppurativa
Authors: Wortsman Ximena , Revuz Jean , Jemec Gregor B.E.
Published: April 2009

Background: Hidradenitis suppurativa (HS) is an inflammatory disease, and yet palpable lymph nodes are rarely found. This may be due to lack of lymph node swelling or to the inability to palpate lymph node regions due to overlying disease. Ultrasound was used to identify and measure regional lymph nodes in HS patients. Methods: High-resolution ultrasound scanning was carried out with compact linear 15–7 MHz and linear 12–5 MHz probes in both axillae and inguinal regions following informed consent. Results: A total of 198 lymph nodes were identified in 6 HS patients in Hurley stage II and 4 in stage III, and 101 from regional control scans in healthy controls. All the lymph nodes in both HS patients and controls showed a normal oval shape, with a hypoechoic rim and a hyperechoic center, and all were located in the deep subcutaneous tissue. The overall mean lymph node number per region was not significantly different. The overall mean lymph node diameter was not significantly different, but in patients with Hurley stage III disease it was significantly increased (1.3 ± 0.4 cm, p = 0.03). Conclusion: Lymph node involvement only occurs with late-stage HS and may therefore reflect secondary infection rather than primary etiological involvement.
Gly80Ser Polymorphism of Phospholipase A2-IID Is Associated with Cytokine Inducibility in A549 Cells
Authors: Igarashi Akira , Shibata Yoko , Yamauchi Keiko , Osaka Daisuke , Takabatake Noriaki , Abe Shuichi , Inoue Sumito , Kimura Tomomi , Yamaguchi Yoko , Ishizaki Jun , Hanasaki Kohji , Kubota Isao
Published: April 2009

Background: The Gly80Ser polymorphism in phospholipase A2-IID (PLA2G2D, NCBI SNP reference: rs584367) is associated with a loss in body weight in patients with chronic obstructive pulmonary disease (COPD). The T allele missense mutation results in the 80th amino acid of the PLA2G2D protein changing from a glycine (Gly; C allele) to a serine (Ser; T allele). COPD patients carrying Ser lose a significant amount of weight compared with those carrying Gly. The mechanism for this weight loss following carriage of this Ser allele has not been clarified. Objectives: We aimed to evaluate whether this allelic change alters PLA2 enzymatic activity and/or pro-inflammatory cytokine inducibility. Methods: A549 cells (a human pulmonary epithelial cell line) were transfected with PLA2G2D-Gly or PLA2G2D-Ser. We evaluated PLA2 activity and cytokine expressions in these cells. Results: The enzymatic activity of sPLA2 in A549-PLA2G2D-Ser cells did not differ from the A549-PLA2G2D-Gly cells. A549-PLA2G2D-Ser cells spontaneously produced higher levels of interleukin (IL)-6 and IL-8 than A549-PLA2G2D-Gly cells. Upon tumor necrosis factor-α stimulation, IL-6 and IL-8 mRNA and protein levels in A549-PLA2G2D-Ser cells were elevated compared with those of A549-PLA2G2D-Gly cells. Upon hydrogen peroxide stimulation, IL-8 mRNA and protein levels in A549-PLA2G2D-Ser cells were higher than those of A549-PLA2G2D-Gly cells. Conclusions:PLA2G2D-Ser enhances the expression of IL-6 and IL-8 compared with PLA2G2D-Gly. This enhanced cytokine expression observed with the allelic change in PLA2G2D may be associated with the body weight loss seen in COPD patients.
Development of Tissue-Engineered Human Periodontal Ligament Constructs with Intrinsic Angiogenic Potential
Authors: Nagai Nobuhiro , Hirakawa Ayumi , Otani Nao , Munekata Masanobu
Published: April 2009

One approach to treat periodontal diseases is grafting of tissue-engineered periodontal ligaments. Therefore, periodontal ligaments were constructed by layering cell sheets. A cell sheet was prepared by enzymatic digestion of salmon collagen gel on which human periodontal ligament fibroblasts (HPLFs) were co-cultured with or without human umbilical vein endothelial cells (HUVECs). Three cell sheets were layered and then cultured in angiogenic media, in which the HUVECs were found to form capillary-like structures when co-cultured on the HPLFs. The layered HPLFs sheets with HUVEC co-culture (PL-EC construct) demonstrated longer survival, higher alkaline phosphatase activities and lower osteocalcin production than layered HPLFs sheets without HUVEC co-culture (PL construct). Hematoxylin-eosin and Masson’s trichrome staining of histological sections showed that cell density, mass and extracellular matrix deposition of the PL-EC construct were higher than those of the PL construct. Furthermore, CD31 immunostaining revealed the formation of capillary-like structures throughout the PL-EC construct. In conclusion, we successfully developed tissue-engineered periodontal ligament constructs with intrinsic angiogenic potential using cell sheet engineering and HUVEC co-culture.
Increased Nuchal Translucency and Other Ultrasound Findings in a Case of Simpson-Golabi-Behmel Syndrome
Authors: Li Chumei C. , McDonald Sarah D.
Published: April 2009

Objectives: Fetal imaging, in particular nuchal translucency, is playing an increasingly important role in diagnosing genetic syndromes. We report imaging findings of a male fetus with Simpson-Golabi-Behmel (SGB) syndrome. Methods and Results: The SGB case was noted to have increased nuchal translucency on integrated prenatal screening, in conjunction with elevated maternal serum alpha fetal protein and body wall edema. Subsequent ultrasound findings at 30 weeks gestation included polyhydramnios, macrosomia, macroglossia, left-sided cleft lip and palate, nephromegaly, hepatosplenomegaly as well as an abnormal skull shape due to lamboid craniosynostosis. Conclusions: To our knowledge this is the first case report of increased nuchal translucency and craniosynostosis associated with SGB syndrome. A mutation in the glypican-3 gene was found in both the proband and the mother, who is a manifesting carrier.
N-Acetylcysteine Prevents Mitochondria from Oxidative Injury Induced by Conventional Peritoneal Dialysate in Human Peritoneal Mesothelial Cells
Authors: Kuo Hung-Tien , Lee Jia-Jung , Hsiao Hui-Hsu , Chen Hsiang-Wen , Chen Hung-Chun
Published: April 2009

Introduction: Bioincompatible peritoneal dialysate fluids (PDFs) may lead to peritoneal injury. The present study investigated the possible effects of N-acetylcysteine (NAC) during conventional PDF exposure for human peritoneal mesothelial cells (HPMCs). Methods: Cultured HPMCs were incubated with conventional 1.5% dextrose PDF for different time periods, and NAC was utilized as the antioxidant. The cell survival, superoxide accumulation, mitochondrial membrane potential (Δψm), expression of heat shock protein 72(HSP72), catalase, superoxide dismutase (SOD), and glutathione content of HPMCs were evaluated. Results: HPMC exposed to PDF resulted in a significant decrease in cell survival in a time-dependent manner, which was reversed by NAC. PDF exposure resulted in intracellular accumulation of superoxide in a time-dependent manner, with collapse of Δψm as well. The activity of enzymatic antioxidant, SOD and catalase remained the same in all groups. However, the reduced glutathione was significantly suppressed after PDF exposure. NAC treatment preserved the content of intracellular reduced glutathione, and also attenuated the PDF-induced superoxide accumulation and Δψm collapse. Moreover, the enhanced expression of HSP72 induced by PDF exposure was also reversed by NAC. Conclusion: Depletion of a nonenzymatic antioxidant, i.e. reduced glutathione, in HPMC is a crucial cause of PDF-induced oxidative stress. NAC protects HPMCs from PDF-induced cellular damage by preserving the reduced glutathione.
Segment-Specific Expression of Netrin-1 Receptors in Normal and Ischemic Mouse Kidney
Authors: Wang Weiwei , Ramesh Ganesan
Published: April 2009

Background/Aims: Netrin-1 plays a key role in the prevention of ischemia reperfusion induced kidney injury by suppressing apoptosis and increasing epithelial cell proliferation. Netrin-1 binds to cell-surface receptors, which include members of the deleted in colorectal cancer (DCC and neogenin), UNC5 homologue and integrin families, to mediate its actions. Kidney is known to express three netrin-1 receptors mRNA (UNC5B, UNC5C and neogenin) abundantly. However, the intrarenal localization of these receptors is unknown. Methods: We analyzed netrin-1 receptor expression in normal kidney and after ischemia reperfusion injury by real-time RT-PCR and immunohistochemistry. Results: We show that UNC5B expression is restricted to S3 segments of proximal tubules, whereas UNC5C expression is restricted to distal tubules. There was no expression of UNC5B and UNC5C in the glomerulus. Neogenin is expressed in all segments of the nephron including the glomerulus. Neogenin expression was restricted to the basolateral membrane in tubular epithelial cells. The expression patterns of UNC5B, UNC5C and neogenin were not altered after ischemia reperfusion injury. In contrast to protein expression, mRNA expression was significantly down-regulated after ischemia reperfusion injury of the kidney. Conclusion: Netrin-1 receptors were expressed in specific segments and may have differential functions in different segments of the nephron.
An Open Pilot Study Exploring the Efficacy of Fluvastatin, Pegylated Interferon and Ribavirin in Patients with Hepatitis C Virus Genotype 1b in High Viral Loads
Authors: Sezaki Hitomi , Suzuki Fumitaka , Akuta Norio , Yatsuji Hiromi , Hosaka Tetsuya , Kobayashi Masahiro , Suzuki Yoshiyuki , Arase Yasuji , Ikeda Kenji , Miyakawa Yuzo , Kumada Hiromitsu
Published: April 2009

Objective: Response to pegylated (PEG) interferon (IFN) and ribavirin is achieved only in 40–50% of patients infected with hepatitis C virus (HCV) of genotype 1 in high viral loads, which needs to be improved. Methods: In an open-label pilot study, fluvastatin (HMG-CoA reductase inhibitor), 20 mg daily, was given along with PEG-IFN/ribavirin to 21 patients with chronic hepatitis C. They were followed for HCV RNA in serum. Results: During treatment for 48 weeks, HCV RNA was lost from serum in 93% of the patients. In the 15 patients who received 48-week therapy, a sustained virological response (SVR) with loss of HCV RNA 24 weeks after completion was achieved in 10 (67%), including 7 of the 9 (78%) male and 3 of the 6 (50%) female patients. In the remaining 6 patients who received 72-week therapy, SVR was gained in 4 (67%), including 1 of the 2 male and 3 of the 4 female patients aged 56, 58 and 62 years, respectively. Conclusion: Fluvastatin could be used safely to increase the response to PEG-IFN and ribavirin, especially in aged women who respond poorly to combined PEG-IFN/ribavirin.
Autoantibodies to Poly(ADP-Ribose) Polymerase in Centenarians: A Reappraisal of Grabar’s Hypothesis
Authors: Lisa Antonella , Monti Daniela , Franceschi Claudio , Scovassi Anna Ivana
Published: April 2009

Background: Centenarians display a characteristic autoantibody profile, this being the absence of organ-specific autoantibodies and an increase in non-organ-specific autoantibodies without any full-blown autoimmune disease. Objective: Antibodies directed to the nuclear protein poly(ADP-ribose) polymerase (PARP) were frequently found in the sera of patients affected by autoimmune diseases. This study aims at investigating the presence of circulating autoantibodies directed against PARP-1 in normal subjects, and searching for a possible correlation between level of circulating autoantibodies and age. Methods:The presence of antibodies to PARP was monitored by ELISA according to a previously developed protocol. Data were analysed by parametric statistics (unpaired t test, χ2 test). Results: Our study performed on 33 centenarians and 66 subjects of age ranging from 12 to 80 years shows that circulating autoantibodies to the nuclear enzyme PARP, previously described in autoimmune diseases, are present in the sera of normal healthy people and increase with age. Conclusions: Taking into account the role of PARP-1 in DNA damage and apoptosis, the data are compatible with Grabar’s hypothesis, which proposed several decades ago that ‘autoreactive antibodies represent a physiological system for disposing the products of metabolism and catabolism’, thereby helping to attain longevity.
Lack of PIVKA Effect in the Abnormal Factor X (Factor X Friuli) Coagulation Disorder
Authors: Girolami A. , Muller A.D. , Hemker H.C.
Published: April 2009

Thrombotest dilution curves and specific inhibitor experiments were carried out in the abnormal factor X (factor X Friuli) plasma and in coumarin plasma. Thrombotest dilution curves obtained with Friuli plasma suggested the presence of a PIVKA-like inhibitor which was not confirmed by the specific experiments. The inhibitory capacity found in Friuli plasma was-0.09 arbitrary units, whereas that found in coumarin-treated patients with a factor X level ranging from 1 to 14% varied between 0.34 and 0.21 arbitrary units.
Isolation of Thrombin-Like Activity from the Venom of Trimeresurus Okinavensis
Authors: Andersson L.
Published: April 2009

An activity that converts bovine fibrinogen to fibrin has been isolated from the crude venom of Trimeresurus Okinavensis by means of gel chromatography and ion exchange chromatography on arginine-Sepharose 6B. A high degree of homogeneity is suggested by gel chromatography, gel electrophoresis, isoelectric focusing and end-group analysis. The purified fraction is an acidic glycoprotein with a molecular weight of about 35,000. It catalyzes the hydrolysis of certain arginine esters, but has very low proteolytic activity towards casein. The fraction has a strong catalytic activity for converting fibrinogen into a fibrin-like compound. A certain factor-X-activating ability persists. It does not activate human factor-XIII zymogen in plasma.
A Simple Device for Measuring Diameters of Fibrinolysis Zones on Fibrin Plates
Authors: Haverkate F.
Published: April 2009

The fibrinolytic activity of a solution is frequently determined by the fibrin plate method, lytic activities of drops being related to the lysed areas in a fibrin layer. A simple device was designed to measure the diameters of fibrinolysis zones. Using the principle of light scattering by the fibrin layer, we could clearly distinguish lysis zones from non-lysed substrate, even from very transparent fibrin. Application of this principle offers the great advantage that zone diameters can be read off directly, rapidly, and accurately on millimetre graph paper underneath the fibrin plate.
Assessment of Respiratory Mechanics in Patients with Sarcoidosis Using Forced Oscillation: Correlations with Spirometric and Volumetric Measurements and Diagnostic Accuracy
Authors: Faria Alvaro C.D. , Lopes Agnaldo J. , Jansen José M. , Melo Pedro L.
Published: April 2009

Background: The forced oscillation technique (FOT) is a promising method for providing a detailed analysis of respiratory mechanics during spontaneous breathing. There is limited data about the use of FOT in patients with sarcoidosis. Objectives: The aims of this study were to test the ability of FOT to describe the changes in respiratory mechanics in sarcoidosis and to evaluate the clinical potential of FOT. Methods: Twenty healthy subjects and 31 patients were studied. All subjects performed spirometric exams, and pulmonary volumes were measured in patients. Resistive data were interpreted using the zero-intercept resistance (R0), the slope of the resistive component of the impedance (S), and the mean resistance (Rm). The analysis of reactance was used to measure the mean reactance (Xm) and the respiratory system dynamic compliance (Cdyn). The total mechanical load was evaluated using the absolute value of the respiratory impedance (Z4Hz). Results: In close agreement with pathophysiological fundamentals, significant (p < 0.001) increases in R0, Rm, and Z4Hz, and reductions in Cdyn (p < 0.003) were observed. S and Xm presented smaller modifications (p < 0.02). All FOT parameters were significantly correlated with spirometric indices. Z4Hz was the most adequate parameter for clinical use (Se = 75%, Sp = 75%), followed by R0 and Rm. Conclusions:FOT parameters were consistent with the pathophysiology of sarcoidosis and were also able to detect the effects of this disease. Because the FOT is easy to perform, such a technique may represent an alternative and/or a complement to other conventional exams to help the clinical evaluations of sarcoidotic patients.
The Influence of COPD on Mortality and Severity Scoring in Community-Acquired Pneumonia
Authors: Snijders Dominic , van der Eerden Menno , de Graaff Casper , Boersma Wim
Published: April 2009

Background: Chronic obstructive lung disease (COPD) is a frequent co-morbidity in patients hospitalised with community-acquired pneumonia (CAP). In recent retrospective studies, higher mortality in patients with CAP and COPD was found. Objectives: The aim of the study was to determine the 30-day mortality and to evaluate the differences in CAP severity scoring in hospitalised patients with COPD. Methods: A subanalysis of a randomized clinical trial was performed. Results: A total of 262 patients with CAP were included. Ninety-five (36.3%) patients had COPD. A total of 28 (10.7%) patients died within 30 days. No differences between patients with and without COPD in 30-day mortality were observed [8 (8.4%) vs. 20 (12.0%), p = 0.37]. In the Pneumonia Severity Index (PSI), significant differences in age, gender and heart rate between patients with and without COPD were observed. Patients with COPD were stratified in higher PSI classes. In the CURB-65 score, age ≥65 years was significantly higher in patients with COPD [72 (75.8%) vs. 88 (52.7%), p = <0.01]. In a multivariate analysis, only the need for intensive care unit admission and high serum glucose were predictors of mortality [OR 32.50 (95% CI 6.87–153.75), p < 0.01; OR 7.34 (95% CI 1.19–45.4), p = 0.03]. Conclusions: Mortality was not increased in patients with COPD hospitalised with CAP. Severity scores are influenced by age and gender. Further studies evaluating CAP in patients with COPD are needed to explain these findings.
Efficacy of Efalizumab in Psoriasis Patients Previously Treated with Tumour Necrosis Factor Blockers
Authors: Costanzo A. , Talamonti M. , Botti E. , Spallone G. , Papoutsaki M. , Chimenti S.
Published: April 2009

Background: Biological therapy for moderate to severe psoriasis includes tumour necrosis factor (TNF) blockers (infliximab, etanercept and adalimumab) and T-cell-targeting agents (efalizumab, alefacept) that act in different steps of a common pathogenic pathway. Large amounts of data coming from clinical trials indicate each of these drugs as highly effective and safe. However, little is known about the efficacy of a second biological therapy after the failure of the first. Objective: To evaluate whether the response to efalizumab in psoriasis patients was influenced by previous treatment with other biological agents. Patients and Methods: We have retrospectively analyzed a group of 155 psoriasis patients treated with efalizumab during the last 5 years and determined its efficacy in patients previously treated with anti-TNF drugs comparing it with the efficacy and safety observed in patients previously treated with traditional systemic drugs instead. Results: Efalizumab was shown to be as efficacious and safe in patients previously treated with biological agents as in those previously treated with traditional systemic drugs. Although not statistically significant, we observed a higher rate of response to efalizumab in patients previously treated with anti-TNF-α. PASI 75 was achieved at week 24 in 76.2% of the patients previously treated with biological agents versus 54.4% in patients previously treated with traditional drugs (OR = 2.9). Conclusions: These data suggest that efalizumab can be successfully used in psoriasis patients when TNF blockers cannot efficiently control the disease due to lack or loss of response, or when they have to be interrupted for intolerance or adverse events.
Simplified Method of Dynamic Contrast-Enhanced Computed Tomography in the Evaluation of Indeterminate Pulmonary Nodules
Authors: Dą;browska Marta , Żukowska Małgorzata , Krenke Rafał , Domagała-Kulawik Joanna , Maskey-Warzęchowska Marta , Bogdan Jerzy , Pacho Ryszard , Chazan Ryszarda
Published: April 2009

Background: Dynamic contrast-enhanced computed tomography (CECT) is one of the methods used in the evaluation of lung nodules. Objectives: The aim of the study was to evaluate the accuracy of the simplified method (based on only 2 postcontrast measurements) of dynamic CECT in determining the nature of pulmonary nodules. Methods: Forty nodules (solid, 10–40 mm in diameter, spherical, with no visible calcification or fatty tissue) in 40 patients were analyzed. In 30 patients, the nature of the nodule was confirmed by pathological examination. In 10 cases, the nodules were assumed to be benign, as no growth within 2 years was radiologically documented. All patients underwent CECT according to a simplified protocol (based on pre-enhancement and 2 postcontrast measurements at 30 s and 4 min after contrast injection). Results: Twenty-three (57.5%) nodules were proved to be malignant and 17 (42.5%) benign. The 7 benign and none of the malignant nodules showed an enhancement value of ≤15 Hounsfield units. Thus, the sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of shortened dynamic CECT were 100, 41, 70, 100 and 75%, respectively. Conclusions: In CECT, contrast enhancement of a pulmonary nodule ≤15 Hounsfield units is a reliable predictor of its benignity. Reduction in the number of postcontrast measurements in the simplified method of dynamic CECT does not influence its sensitivity.
Thrombocytosis in Rats Induced by Vinblastine
Authors: Klener P. , Donner L. , Housková J.
Published: April 2009

Blood platelet count was studied in 188 normal Wistar rats following administration of vinblastine (VBL). VBL in doses of 0.1 or 0.5 mg/kg causes significant thrombocytosis in normal rats. Prior to thrombocytosis, an increase of megakaryocytes in the bone marrow appears, which does not seem to be a reaction on any thrombocytopenic period. These findings may lead to the conclusion that VBL has a stimulating effect on thrombocytopoiesis in rats.
The Action and Inhibition of the Fibrinogen-Clotting Enzyme from the Venom of Trimeresurus Okinavensis
Authors: Andersson L.
Published: April 2009

Bovine fibrinogen was subjected to hydrolysis by a purified enzyme isolated from the venom of Trimeresurus Okinavensis. One main peptide which was identified as fibrinopeptide A was obtained, together with a very small amount of fibrinopeptide B. The enzyme was found to hydrolyze certain esters, but had no activity towards aromatic esters or insulin B chain. It was found to be a serine esterase and to be independent of metal ions. Typical high molecular weight thrombin inhibitors did not affect the enzyme. Human plasma, which rapidly inactivates thrombin, had no effect on the venom enzyme. Pentamidine, a low molecular weight thrombin inhibitor, was a strong inhibitor of the venom enzyme. Certain peptides known to affect the action of thrombin on fibrinogen also interacted with the present enzyme, but with quite another specificity. The inhibition studies made it possible to provide an explanation of the relative inability to split off the B peptide.
On the Interpretation of Thrombelastograms
Authors: Blair Scott , Matchett R.H.
Published: April 2009

The nature of the physical properties measured by the thrombelastograph is discussed and an equation is proposed which enables almost the whole of the data obtained during the process of blood clotting to be described in terms of three meaningful parameters.
Comparative Studies of the Fibrinolytic System in Rats and Humans
Authors: Hilgard P.
Published: April 2009

Components of the fibrinolytic system were determined in human and rat plasma. Rat plasma has a significantly higher plasminogen activator content which is counterbalanced by a higher plasmin inhibitor level. The plasma plasminogen concentration is somewhat higher in humans. The trypsin inhibitor did not differ significantly in humans and rats. Identical values for plasminogen were found in human plasma when activated with streptokinase or urokinase. The necessity of a correct streptokinase concentration in the assay system is stressed. From the data presented it is concluded that the rat is a suitable animal to study fibrinolysis under experimental conditions.
The Mechanism of Intravascular Activation of the Fibrinolytic System during Hormonal Contraception
Authors: Asbeck F. , Bolte A. , Henning H.D. , Hördemann K. , Latz R. , Lechler E. , van de Loo J.
Published: April 2009

The fibrinolytic system in 18 healthy women treated with an oral contraceptive hormone (Eugynon®: 50 µg ethinyl estrenol, 500 µg norgestrel) was studied repeatedly over 3 months. An increased level of immunoreactive plasminogen, as well as Fibrinogen degradation products an increased plasmin and activator activity, could be demonstrated. Venous occlusion experiments were suggestive for an enhancement of local activator release during the treatment. The level of fibrinogen degradation products, however, remained unchanged. It is concluded that thrombophilia under contraceptive hormone treatment cannot be explained by disturbances of the fibrinolytic system.
Effect of the Polyene Antibiotic Filipin on the Lipid-Dependent Intrinsic Pathway of Blood Coagulation
Authors: van der Plas P.M. , Kraan L. , van Es G. , Stibbe J. , Hemker H.C.
Published: April 2009

Clotting along the intrinsic pathway can be inhibited by the polyene antibiotic filipin. Besides inhibition of the prothrombinase complex (in the common pathway of intrinsic and extrinsic coagulation) a clot-delaying effect depending on the cholesterol content of the lipid for the formation of the factor VIII-IX lipid complex was found. The adsorption of factors VIII and IXa onto lipids is slightly enhanced by filipin. This phenomenon does not lead to an increase of factor X-converting activity.
Thrombocyte and Megathrombocyte Kinetics during Thrombocytosis Induced by Acute and Chronic Blood Loss and by Iron Deficiency Diet
Authors: Garg S.K. , Weiner M. , Karpatkin S.
Published: April 2009

The mechanism of blood loss-induced thrombopoiesis was studied by measuring thrombocyte and megathrombocyte (young platelet) kinetics in guinea pigs made thrombocytotic by acute or chronic blood loss. The effect of an Fe-deficient diet was also examined. Acute and chronic blood loss raised the platelet count 1.2- and 1.4-fold, respectively Simultaneous replacement of Fe loss raised the platelet count 2.1- and 2.5-fold in acute and chronic blood loss, respectively. Paradoxically, an Fe-deficient diet also raised the platelet count 1.4-fold. Megathrombocyte number increased 1.4-fold more than the increase in platelet count for both acute and chronic blood loss. Simultaneous replacement of Fe produced an increase in megathrombocyte number which was 1.8- and 1.6-fold greater than the increase in platelet count for acute and chronic blood loss, respectively. Animals on an Fe-deficient diet did not raise their megathrombocyte number above their rise in platelet count. Thus, Fe is required for megathrombocyte production. A two-compartment system is postulated for the effect of Fe on thrombocytosis. (1) Fe inhibits the rise in platelet count above steady-state levels. (2) Fe is also required for maximum platelet production above steady-state levels via the production of megathrombocytes.The increment in megathrombocyte production following acute or chronic blood loss could account for one-quarter of thrombocyte production if one megathrombocyte gives rise to one thrombocyte. Alternatively, one megathrombocyte could give rise to four thrombocytes in the peripheral circulation. It is suggested that this latter mechanism may be important physiologically.
Heparin-Neutralizing Factor (Platelet Factor 4) from Human Blood Platelets and its Reactivity with Fibrinogen and Soluble Fibrin-Monomer Complexes
Authors: Käser-Glanzmann Rosmarie , Jakábová Milica , Lüscher E.F.
Published: April 2009

The heparin-neutralizing factor (PF4) has been isolated from the supernatant of thrombin-treated, washed human blood platelets. The major part of the factor is present as a PF4-proteoglycan complex which can be dissociated at higher ionic strength. PF4 thus obtained is a basic protein of molecular weight 29,700. The carrier proteoglycan will recombíne with a maximum of 4 molecules of PF4, whereby dimerization of the resulting complex is observed. This is in contrast to the naturally occurring, released complex, which has a sedimentation constant which is rather compatible with the presence of monomeric material. Heparin displaces PF4 from its proteoglycan carrier; thereby a 1:1 heparin PF4 complex is formed. Contrary to preparations obtained by zinc precipitation, neither the PF4-carrier complex, nor purified PF4 obtained by dissociation at high ionic strength form insoluble complexes with fibrinogen or with complexes formed from fibrin-monomers and fibrinogen degradation products. Pretreatment of zinc-precipitated PF4 with EDTA abolishes its paracoagulating properties.
Aggregation of Human Platelets by Commercial Porcine and Bovine Fibrinogen Preparations
Authors: Forbes Charles D. , Prentice Colin R.M.
Published: April 2009

Commercial preparations of porcine and bovine fibrinogen which produce aggregation of human platelets have been shown to contain a high molecular weight compound. This material produces platelet aggregation and has procoagulant, chemical and antigenic identity with antihaemophilic factor.
Effect of Reserpine on 14C-Serotonin Uptake by Human Platelet Populations
Authors: Rendu F. , Caen J.P.
Published: April 2009

The incorporation of 14C-5HT is inhibited by reserpine in heavy (young) human platelets, whereas it is enhanced in light (old) platelets. These findings are interpreted to mean that active uptake takes place in heavy (young) platelets, which probably have intact membranes rich in serotonin receptors, and a full content of ATP in storage granules, whereas passive diffusion is predominant in light (old) platelets.
The Influence of the Polyene Filipin on the Extrinsic Pathway of Blood Coagulation
Authors: van der Plas P.M. , van Es G. , Kraan L. , Hemker H.C.
Published: April 2009

The inhibition by filipin in the extrinsic blood clotting system takes place at two sites: (1) at the interaction of factor VII, tissue thromboplastin and Ca++, and (2) at the prothrombinase level. Both formation and enzymatic activity of the prothrombinase are inhibited.The cholesterol content of the lipid that is used to form the prothrombinase complex determines the degree of inhibition by filipin. The inhibition increases the higher the sterol content. The adsorption of factors Xa and V onto lipid surface is enhanced by filipin. This increased adsorption does not lead to an increase in prothrombinase production.
Denaturation of Fibrinogen, the Protective Effect of Calcium
Authors: Ly B. , Godal H.C.
Published: April 2009

Small amounts of calcium provide protection of fibrinogen against moderate denaturation by heat or alkali. This protection remains despite dialysing the solution. These observations suggest that calcium might prevent denaturation of fibrinogen during preparation and storage.
Preparation of Human Fibrinogen Free of Plasminogen by Immunoadsorption
Authors: Luke K.H. , Hirsh J. , Bienenstock J. , Zipursky A. , Johnson M. , Allman K.
Published: April 2009

Human fibrinogen was purified free of plasminogen by a simple immunoadsorption technique using an insoluble polymer complex of an anti-plasminogen antiserum cross-linked by ethylchloroformate. The anti-plasminogen antiserum was prepared in guinea pigs by immunization with purified human plasminogen. The fibrinogen so purified was free of plasminogen as demonstrated by immunological and biological assays and did not show changes in clottability, thrombin clotting time and reactivity to plasmin, and is suitable as a reagent for plasmin and anti-plasmin assays for diagnostic purposes.
An Automated Immuno-Nephelometric Method for the Quantitative Determination of Plasma Fibrinogen
Authors: Dessert J. , Bocquet P. , Belleville J. , Later R. , Quincy C.
Published: April 2009

An immuno-nephelometric me- thod, in a continuous flow system for the determination of plasma fibrinogen is described. The method is specific, rapid (60 determinations per hour), requires only 0.03 ml of plasma and compares favourably (r = 0.923 ± 0.038) with Leclerc’s colorimetric method.
A Screening Test for Factor VIII Antibodies
Authors: Denson K.W.E. , Das K.K.
Published: April 2009

A screening test has been investigated for detecting factor VIII antibodies, based on the observation of Strauss and Merler that a lower initial concentration of factor VIII detects weaker antibodies. At an initial factor VIII concentration of 0.1 β/ml weak antibodies are detected which would not be revealed at the higher concentration of factor VIII normally employed. The most suitable sources of factor VIII are cryoprecipitate and normal human plasma, whilst human factor VIII is less satisfactory.
Antibody Neutralization in Hypoprothrombinaemic Plasma
Authors: Parkin J.D. , Madaras F. , Castaldi P.A.
Published: April 2009

The technique of antibody neutralization has been used to study the plasma of a large group of patients with hypoprothrombinaemia of diverse causes. The associated disorders included obstructive jaundice, acute infective hepatitis and chronic parenchymal liver disease. A number of patients were receiving warfarin and salicylate therapy. Irrespective of the aetiology of the prolonged prothrombin time, patients were demonstrated with an excess of clotting protein over clotting activity for factors II, VII, IX and X. In general, this discrepancy paralleled the prolongation of the prothrombin time.
Preprothrombin and Prothrombin in Full-Term Newborns
Authors: Schettini Franco , de Mattia Domenico , Mautone Angela
Published: April 2009

Three activities of factor II (prothrombin, prothrombin-coagulase and antigenic activity) have been evaluated in full-term newborns on the first 5 days of life. Prothrombin activity is similar to prothrombin-coagulase activity on the 1st day of life and on the 3rd day the two activities decrease simultaneously. The prothrombin activity rises again towards the 5th day, contrary to the prothrombin-coagulase activity which continues to decrease. If vitamin K1 is not administered, the decrease in the two activities on the 3rd day is more marked. The antigenic activity of factor II does not show significant variations from the 1st to the 5th day of life; it always remains inferior to the values observed in adults.
Estrogen and Hyperaggregability of Platelets Measured by the Screen Filtration Pressure (SFP) Method in Takayasu’s Disease
Authors: Yamazaki Hiroh , Numano Fujie , Numano Fujio , Shimamoto Takio
Published: April 2009

Platelet aggregability in 10 females (32.2 ± 3.1 years) with Takayasu’s disease and 16 healthy males (31.7 ± 2.7 years) and 14 females (28.6 ± 2.8 years) was measured by the screen filtration pressure (SFP) method. SFP of the healthy males was 202.6 ± 5.4 mm Hg at 3 μM and 118.5 ± 8.0 mm e Hg at 1 /m of ADP, and of the healthy females 264.9 ± 14.3 mm Hg at 3 μM and 162.8 ± 11.9 mm Hg at 1 μM of ADP. SFP of the Takayasu’s disease patients was 360.0 ± 35.7 mm Hg at 3 μM and 229.2 ± 32.5 mm Hg at 1 μM of ADP. The difference between the three groups above was significant (p < 0.05). A positive correlation (r = 0.887, p < 0.05) between SFP at 3 μM of ADP of the patients and the daily urinary estrogen excretion was recognized.
Morphological Findings in Microangiopathic Hemolytic Anemia
Authors: Klein P.J. , Schaefer H.E. , de Lacroix Féaux , Fischer R.
Published: April 2009

The clinical diagnosis of microangiopathic hemolytic anemia (MHA) can be ascertained only by the prove of fragmentocytes (schistocytes) in the peripheral blood. Those fragmented red cells caused by different processes of microangiopathy are partly destroyed in the blood vessels, partly absorbed by the reticuloendothelial system and may produce typical histomorphological changes. Therefore, besides the histological classification of the microangiopathy in 15 autopsy cases (Moschcowitz’ syndrome 4, hemolytic uremic syndrome 2, glomerular microthrombosis 1, eclampsia 1, malignant nephrosclerosis 1, anaphylactoid purpura 1, and metastatic tumors 5) parameters of MHA are additionally studied, which are depending on the hemolysis in this disease. The earliest morphological findings in MHA are hemoglobin casts in distal convoluted tubules of the kidney and siderosis of the reticuloendothelial system (RES) in spleen and liver and siderosis of the proximal convoluted tubules of the kidney. Extramedullary hematopoiesis of spleen and sometimes of liver is seen in a later phase of MHA. These indicative signs of MHA, hitherto widely unrecognized, show a good correlation to the duration of the disease and the extent of microangiopathy.
Platelet Aggregation by Ristocetin in EDTA Plasma: Extensive Clumping with High Concentrations of EDTA
Authors: Ts’ao Chung-Hsin
Published: April 2009

Human blood platelets prepared from EDTA blood were aggregated by ristocetin without the addition of divalent cations. Platelets obtained from blood anticoagulated with a high concentration of EDTA responded to ristocetin more extensively than those with 1/10 the strength of EDTA. Aspirin ingestion did not affect the aggregation of EDTA platelets by ristocetin.
Influence of pH on the Incorporation of Fibrinogen Degradation Products into Fibrin Clots as Studied by Tracer Technique
Authors: Ly B. , Arnesen H.
Published: April 2009

Fibrinogen degradation products (FDP) interfere with coagulation of fibrinogen and may lead to incorrect estimates of fibrinogen in plasma and of FDP in serum. At pH 7.8 as much as 50–60 % of early FDP were incorporated into clots made from whole blood or from plasma, whereas late FDP were incorporated to minor extent. By lowering pH to 6.3, incorporation of early FDP was markedly reduced. The amount of unclotted fibrin due to the presence of FDP was also reduced. Thus, for a more correct estimate of FDP in serum, it is suggested that pH of blood or plasma should be lowered prior to clotting. Estimation of fibrinogen according to the Jacobsson assay (pH 6.3) is fairly exact in the presence of FDP, except at very high FDP concentrations.