Cor triatriatum simulating a left atrial mass in adult patient

We report a case of non-thrombosed cor triatriatum sinister simulating a cardiac mass on thoracic CT angiogram in a 58-year-old man presenting with acute chest pain. Following additional imaging with cardiac CT and MRI, and otherwise unremarkable cardio-pulmonary work-up, diagnosis of presumably coincidental cor triatriatum was established.

Predictors of attrition in a smoking cessation trial conducted in the lung cancer screening setting

SIGNIFICANCE

Although it is a requirement that tobacco treatment is offered to cigarette smokers undergoing low-dose computed tomographic lung cancer screening (LCS), not all smokers engage in treatment. To understand the barriers to tobacco treatment in this setting, we evaluated predictors of attrition in a smoking cessation trial among individuals undergoing LCS.

METHODS

Prior to LCS, 926 participants, 50-80 years old, completed the baseline (T0) phone assessment, including demographic, clinical, tobacco, and psychological characteristics. Following LCS and receipt of the results, participants completed the pre-randomization (T1) assessment.

RESULTS

At the T1 assessment, 735 (79%) participants were retained and 191 (21%) dropped out. In multivariable analyses, attrition was higher among those who: smoked >1 pack per day (OR = 1.44, CI 1.01, 2.06) or had undergone their first (vs. annual) LCS scan (OR = 1.70, CI 1.20, 2.42). Attrition was lower among those with: more education (associates (OR = 0.67, CI = 0.46, 0.98) or bachelor's degree (OR = 0.56, CI 0.35, 0.91) vs. high school/GED), some (vs. none/a little) worry about lung cancer (OR = 0.60, CI 0.39, 0.92), or a screening result that was benign (OR = 0.57, CI 0.39, 0.82) or probably benign (OR = 0.38, CI 0.16, 0.90) vs. negative.

CONCLUSIONS

This study illuminated several LCS-related factors that contributed to trial attrition. Increasing tobacco treatment in this setting will require targeted strategies for those who report little lung cancer worry, are undergoing their first LCS exam, and/or who have a negative LCS result. Addressing attrition and reducing barriers to tobacco treatment will increase the likelihood of cessation, thereby reducing the risk of developing lung cancer.

Natural Language Processing and Machine Learning for Detection of Respiratory Illness by Chest CT Imaging and Tracking of COVID-19 Pandemic in the US

BACKGROUND

Coronavirus disease 2019 (COVID-19) has spread quickly throughout the United States (US) causing significant disruption in healthcare and society. Tools to identify hot spots are important for public health planning. The goal of our study was to determine if natural language processing (NLP) algorithm assessment of thoracic computed tomography (CT) imaging reports correlated with the incidence of official COVID-19 cases in the US.

METHODS

Using de-identified HIPAA compliant patient data from our common imaging platform interconnected with over 2,100 facilities covering all 50 states, we developed three NLP algorithms to track positive CT imaging features of respiratory illness typical in SARS-CoV-2 viral infection. We compared our findings against the number of official COVID-19 daily, weekly and state-wide.

RESULTS

The NLP algorithms were applied to 450,114 patient chest CT comprehensive reports gathered from January 1st to October 3rd, 2020. The best performing NLP model exhibited strong correlation with daily official COVID-19 cases (r2=0.82, p<0.005). The NLP models demonstrated an early rise in cases followed by the increase of official cases, suggesting the possibility of an early predictive marker, with strong correlation to official cases on a weekly basis (r2=0.91, p<0.005). There was also substantial correlation between the NLP and official COVID-19 incidence by state (r2=0.92, p<0.005).

CONCLUSION

Using big data, we developed a novel machine-learning based NLP algorithm that can track imaging findings of respiratory illness detected on chest CT imaging reports with strong correlation with the progression of the COVID-19 pandemic in the US.

Prevalence, Follow-Up and Clinical Significance of the Anticardiolipin Antibodies in Normal Subjects

To date very few studies that analyze the prevalence of anticardiolipin antibodies (ACA) in healthy subjects have been reported. No data based on a systematic analysis of normal subjects with positive ACA is available. The aim of the present study was to evaluate the prevalance of ACA, its clinical significance and relationship to the lupus anticoagulant (LA) and other autoimmune parameters in an apparently healthy population. 552 normal blood donors from a blood bank were randomly selected. ACA positive donors who consented were monitored over a period of twelve months and tested every three months. ACA (IgG and IgM isotypes) were quantitated by enzyme linked immunoassay (ELISA). The prevalance for IgG ACA in our donor population was estimated to be 6.5%, and 9.4% for IgM ACA, which is similar to the one previously reported for IgG and slightly higher for IgM. It is worth noting that in our study ACA positive donors exhibited a progressive negativization. Eight donors with IgG ACA and seven with IgM ACA remained positive for nine months. Five donors with IgG ACA and four with IgM ACA had family history of thromboembolic disease. One donor with IgG ACA and two with IgM ACA had had unexplained miscarriages in the past. We did not find any relationship between ACA and LA, nor between ACA positivity and the clinical and laboratory data studied. Pseudopositivity for lues was not found. No thrombotic event occurred in donors that were positive for ACA during the 12-month follow-up.

Effect of Dextran on Factor Vlll/von Willebrand Factor Structure and Function

Factor VIII/von Willebrand factor was analyzed before and after the infusion of 500 ml of Dextran 70 to normal volunteers. Factor VIII procoagulant activity, factor VIII related antigen and ristocetin cofactor activity showed a significant decrease, reaching after six hours the minimum level, which did not correlate with the hemodilution effect caused by dextran. Ristocetin-induced platelet agglutination (RIPA) in volunteers’ platelet-rich plasma (PRP) did not show any significant change between preinfusion time and six hours after the infusion. Multimeric analysis of von Willebrand factor (vWF) showed a progressive decrease of all the multimers which was more pronounced in the largest multimers. No change was seen in the “triplet” structure of vWF. No effect was noticed when dextran was incubated “in vitro” either with PRP or platelet-poor plasma. The modification induced by dextran is close to the pattern seen in subtype Ib von Willebrand’s disease.

Abnormal Structure of von Willebrand Factor in Myeloproliferative Syndrome Is Associated to Either Thrombotic or Bleeding Diathesis

The multimeric and subunit patterns of plasma von Willebrand factor (vWF) were analyzed in eight patients with myeloproliferative syndrome (MS) in order to investigate the possible existence of heterogeneity in the “in vivo” proteolytic cleavage of the protein, previously observed in this entity. Six patients lacked large vWF multimers, five of them having normal bleeding times (BT) and clinically documented episodes of thrombotic origin, whereas one patient had long BT and bleeding symptoms. Seven patients showed a relative increase in the 176 kDa subunit fragment while the 189 kDa polypeptide was increased in only one. In addition, another patient (and prior to any therapy) showed the presence of a new fragment of approximately 95 kDa which disappeared after Busulfan therapy. The collection of blood from these patients with proteinase inhibitors did not correct the abnormalities.

The infusion of DDAVP to two patients with abnormal vWF was accompanied by: the appearance of larger vWF multimers which disappeared rapidly from plasma; an increase in the relative proportion of the satellite bands of each multimer and a further increase of the 176 kDa fragment. These data point to some heterogeneity in the vWF abnormality present in MS which may be related in part to a variable degree of proteolysis of vWF occurring “in vivo” rather than “in vitro”, and which may be associated to either a thrombotic or a bleeding diathesis. They also suggest that despite the presence of abnormal, already proteolyzed vWF, DDAVP-enhanced proteolysis occurs in MS to a similar extent to what is described in normal individuals.

[One-year results on the safety and efficacy of the InnFocus MicroShunt™ depending on placement and concentration of mitomycin C]

PURPOSE

To compare intraocular pressure (IOP) at one year with the InnFocus MicroShunt(®) with or without cataract surgery with according to placement and concentration of mitomycin C (MMC) DESIGN: A retrospective two-center, two-surgeon study (France and Dominican Republic).

PATIENTS AND METHODS

Adults with POAG requiring filtering surgery. One MicroShunt(®) was placed in one eye of each patient. The effect of concentration and site of application of MMC was assessed by IOP and medication reduction at one year.

RESULTS

Eighty-seven eyes were studied with one-year follow-up. Twenty-three eyes treated with 0.4 mg/mL MMC close to the limbus demonstrated a 55% reduction in IOP from 23.8 ± 5.3 at baseline to 10.7 ± 2.8 mmHg at one year. Topical glaucoma medication/patient was reduced 85% from 2.4 ± 0.9 to 0.3 ± 0.8. Thirty-one eyes treated with 0.2mg/mL MMC close to the limbus demonstrated a 52% reduction in IOP from 27.9 ± 6.7 at baseline to 13.3 ± 3.3 mmHg at one year. Topical glaucoma medication/patient was reduced 88% from 2.5 ± 1.4 to 0.5 ± 1.0. Thirty-three eyes treated with 0.4 mg/mL MMC deep in the pocket demonstrated a 38% reduction in IOP from 25.4 ± 7.9 at baseline to 15.7 ± 4.6 mmHg at one year. Topical glaucoma medication/patient was reduced 72% from 2.9 ± 1.0 to 0.8 ± 1.3. There were no sight-threatening long-term adverse events.

CONCLUSION

The InnFocus MicroShunt(®) is a filtering surgery whose efficacy is related to the location of application and concentration of MMC used.

Diagnosis of inherited von Willebrand disease: comparison of two methodologies and analysis of the discrepancies

Diagnostics of von Willebrand disease (VWD) includes assessment of factor VIII (FVIII) coagulant activity, von Willebrand factor (VWF) antigen (VWF:Ag) and VWF ristocetin cofactor activity (VWF:RCo), and more specific tests as multimeric and genetic analyses are necessary for the correct VWD classification. The ACL AcuStar analyzer introduces chemiluminescence (CL) technology in detection of VWD with automated VWF:Ag and VWF:RCo assays. Compare VWF:Ag-ELISA and VWF:RCo by aggregometry conventional assays with new CL VWF:Ag-IL and VWF:RCo-IL assays, investigate the ability to make accurate VWD diagnosis and concordance with multimeric and genetic analyses. 146 patients with congenital VWD (51 Type 1; 34 Type 2A; 16 Type 2B; 31 Type 2M; 5 Type 2N; 9 Type 3) and 30 healthy normal subjects were included. A comparison was made between CL and conventional methods. Diagnostic evaluation included: VWF:RCo/VWF:Ag ratio, multimeric distribution (sodium dodecyl sulfate [SDS]-agarose gel) of VWF and genetic analysis in 110 of 146 patients. CL and conventional methods revealed good correlation. Kappa test agreement diagnosis was >0.8. CL diagnostic sensitivity was 100% and specificity 97%. Multimeric and genetic analysis were of help in clarifying 13 discrepancies of diagnosis between methods, of which six discrepancies were explained by lack of conventional methods′ sensibility. CL methodology can detect VWD and discriminate between type 1, 3 and variant forms and offers an automated, faster, sensitive and less cumbersome method when compared to conventional assays, in particular VWF:RCo by aggregometry. In some cases, even with all phenotype and genetic analyses, discrepancies exist in the classification of VWD.

Femtosecond laser-assisted cataract surgery with integrated optical coherence tomography

About one-third of people in the developed world will undergo cataract surgery in their lifetime. Although marked improvements in surgical technique have occurred since the development of the current approach to lens replacement in the late 1960s and early 1970s, some critical steps of the procedure can still only be executed with limited precision. Current practice requires manual formation of an opening in the anterior lens capsule, fragmentation and evacuation of the lens tissue with an ultrasound probe, and implantation of a plastic intraocular lens into the remaining capsular bag. The size, shape, and position of the anterior capsular opening (one of the most critical steps in the procedure) are controlled by freehand pulling and tearing of the capsular tissue. Here, we report a technique that improves the precision and reproducibility of cataract surgery by performing anterior capsulotomy, lens segmentation, and corneal incisions with a femtosecond laser. The placement of the cuts was determined by imaging the anterior segment of the eye with integrated optical coherence tomography. Femtosecond laser produced continuous anterior capsular incisions, which were twice as strong and more than five times as precise in size and shape than manual capsulorhexis. Lens segmentation and softening simplified its emulsification and removal, decreasing the perceived cataract hardness by two grades. Three-dimensional cutting of the cornea guided by diagnostic imaging creates multiplanar self-sealing incisions and allows exact placement of the limbal relaxing incisions, potentially increasing the safety and performance of cataract surgery.

[Multiple sclerosis epidemiological situation update: pertinence and set-up of a population based registry of new cases in Catalonia]

INTRODUCTION

The first epidemiological studies on multiple sclerosis (MS) around the world pictured a north to south latitudinal gradient that led to the first genetic and environmental pathogenic hypothesis. MS incidence seems to be increasing during the past 20 years based on recent data from prospective studies performed in Europe, America and Asia. This phenomenon could be explained by a better case ascertainment as well as a change in causal factors. The few prospective studies in our area together with the increase in the disease in other regions, justifies an epidemiological MS project in order to describe the incidence and temporal trends of MS.

DEVELOPMENT

A prospective multicenter MS registry has been established according to the actual requirements of an epidemiological surveillance system. Case definition is based on the fulfillment of the McDonald diagnostic criteria. The registry setting is the geographical area of Cataluna (northeastern Spain), using a wide network of hospitals specialized in MS management.

CONCLUSION

Recent epidemiological studies have described an increase in MS incidence. In order to contrast this finding in our area, we consider appropriate to set up a population based registry.

Haemophilia in Spain

To determine the prevalence of haemophilia A and B and their complications in Spain, and to characterize the health care network providing support to haemophiliac patients. The study examines clinical and genetic characteristics, treatment options, and complications observed during the course of the disease. Cross-sectional multi-centre study. The study population were patients with HA and HB in active follow-up at any Spanish hospital by December 2006. We studied 2400 haemophiliacs, 2081 (86.7%) HA and 319 (13.3%) HB patients. Illness was severe in 32.3% of patients, moderate in 16.4%, and mild in 51.3%. Genetic screening was carried out in 32.6% of the patients. Treatment administered in 2006 consisted of coagulation factor concentrates in 60% of patients. Until December 2006, 45.8% of severely ill patients were taking prophylaxis. The mean number of bleeding episodes in 2006 was four for patients not receiving primary prophylaxis and 1.3 for those taking primary prophylaxis. Thirty percent of patients had established haemophiliac arthropathy in at least one joint; 16.8% of patients were HIV-infected and 34.8% HCV-infected. Inhibitors were detected in 10% of severe HA patients and in 6.5% of severe HB patients. Immune tolerance induction therapy was started in 34 patients. This is the first comprehensive study on the epidemiology of haemophilia in Spain. It will enable us to draw comparisons with neighbouring countries, to assess the quality of care provided to haemophiliacs in Spain, and to provide evidence-based guidance for the even provision and improvement of such care.

Expression of 14 von Willebrand factor mutations identified in patients with type 1 von Willebrand disease from the MCMDM-1VWD study

BACKGROUND

Candidate von Willebrand factor (VWF) mutations were identified in 70% of index cases in the European study 'Molecular and Clinical Markers for the Diagnosis and Management of type 1 von Willebrand Disease'. The majority of these were missense mutations.

OBJECTIVES

To assess whether 14 representative missense mutations are the cause of the phenotype observed in the patients and to examine their mode of pathogenicity.

METHODS

Transfection experiments were performed with full-length wild-type or mutant VWF cDNA for these 14 missense mutations. VWF antigen levels were measured, and VWF multimer analysis was performed on secreted and intracellular VWF.

RESULTS

For seven of the missense mutations (G160W, N166I, L2207P, C2257S, C2304Y, G2441C, and C2477Y), we found marked intracellular retention and impaired secretion of VWF, major loss of high molecular weight multimers in transfections of mutant constructs alone, and virtually normal multimers in cotransfections with wild-type VWF, establishing the pathogenicity of these mutations. Four of the mutations (R2287W, R2464C, G2518S, and Q2520P) were established as being very probably causative, on the basis of a mild reduction in the secreted VWF or on characteristic faster-running multimeric bands. For three candidate changes (G19R, P2063S, and R2313H), the transfection results were indistinguishable from wild-type recombinant VWF and we could not prove these changes to be pathogenic. Other mechanisms not explored using this in vitro expression system may be responsible for pathogenicity.

CONCLUSIONS

The pathogenic nature of 11 of 14 candidate missense mutations identified in patients with type 1 VWD was confirmed. Intracellular retention of mutant VWF is the predominant responsible mechanism.

Detailed von Willebrand factor multimer analysis in patients with von Willebrand disease in the European study, molecular and clinical markers for the diagnosis and management of type 1 von Willebrand disease (MCMDM-1VWD)

BACKGROUND

Type 1 von Willebrand disease (VWD) is a congenital bleeding disorder characterized by a partial quantitative deficiency of plasma von Willebrand factor (VWF) in the absence of structural and/or functional VWF defects. Accurate assessment of the quantity and quality of plasma VWF is difficult but is a prerequisite for correct classification.

OBJECTIVE

To evaluate the proportion of misclassification of patients historically diagnosed with type 1 VWD using detailed analysis of the VWF multimer structure.

PATIENTS AND METHODS

Previously diagnosed type 1 VWD families and healthy controls were recruited by 12 expert centers in nine European countries. Phenotypic characterization comprised plasma VWF parameters and multimer analysis using low- and intermediate-resolution gels combined with an optimized visualization system. VWF genotyping was performed in all index cases (ICs).

RESULTS

Abnormal multimers were present in 57 out of 150 ICs; however, only 29 out of these 57 (51%) had VWF ristocetin cofactor to antigen ratio below 0.7. In most cases multimer abnormalities were subtle, and only two cases had a significant loss of the largest multimers.

CONCLUSIONS

Of the cases previously diagnosed as type 1 VWD, 38% showed abnormal multimers. Depending on the classification criteria used, 22 out of these 57 cases (15% of the total cohort) may be reclassified as type 2, emphasizing the requirement for multimer analysis compared with a mere ratio of VWF functional parameters and VWF:Ag. This is further supported by the finding that even slightly aberrant multimers are highly predictive for the presence of VWF mutations.

Impact of plasma von Willebrand factor levels in the diagnosis of type 1 von Willebrand disease: results from a multicenter European study (MCMDM-1VWD)

BACKGROUND

Presence of bleeding symptoms, inheritance and reduced von Willebrand factor (VWF) contribute to the diagnosis of type 1 von Willebrand disease (VWD). However, quantitative analysis of the importance of VWF antigen (VWF:Ag) and ristocetin cofactor activity (VWF:RCo) levels in the diagnosis is lacking.

OBJECTIVES

To evaluate the relative contribution of VWF measurement to the diagnosis of VWD.

PATIENTS AND METHODS

From the MCMDM-1VWD study cohort, 204 subjects (considered as affected by VWD based on the enrolling Center diagnoses and the presence of linkage with the VWF locus) were compared with 1155 normal individuals. Sensitivity, specificity and diagnostic positive likelihood ratios (LR) of VWF:Ag and VWF:RCo were computed.

RESULTS

ABO blood group was the variable most influencing VWF levels, but adjustment of the lower reference limit for the ABO group did not improve sensitivity and specificity of VWF:Ag or VWF:RCo. The lower reference limit (2.5th percentile) was 47 IU dL(-1) for both VWF:Ag and VWF:RCo and showed similar diagnostic performance [receiver-operator curve area: 0.962 and 0.961 for VWF:Ag and VWF:RCo, respectively; P = 0.81]. The probability of VWD was markedly increased only for values below 40 IU dL(-1) (positive LR: 95.1 for VWF:Ag), whereas intermediate values (40 to 60 IU dL(-1)) of VWF only marginally indicated the probability of VWD.

CONCLUSIONS

Although the conventional 2.5 lower percentile has good sensitivity and specificity, only VWF:Ag or VWF:RCo values below 40 IU dL(-1) appear to significantly indicate the likelihood of type 1 VWD. The LR profile of VWF level could be used in a diagnostic algorithm.

A quantitative analysis of bleeding symptoms in type 1 von Willebrand disease: results from a multicenter European study (MCMDM-1 VWD)

BACKGROUND

A quantitative description of bleeding symptoms in type 1 von Willebrand disease (VWD) has never been reported.

OBJECTIVES

The aim was to quantitatively evaluate the severity of bleeding symptoms in type 1 VWD and its correlation with clinical and laboratory features.

PATIENTS AND METHODS

Bleeding symptoms were retrospectively recorded in a European cohort of VWD type 1 families, and for each subject a quantitative bleeding score (BS) was obtained together with phenotypic tests.

RESULTS

A total of 712 subjects belonging to 144 families and 195 controls were available for analysis. The BS was higher in index cases than in affected family members (BS 9 vs. 5, P < 0.0001) and in unaffected family members than in controls (BS 0 vs. -1, P < 0.0001). There was no effect of ABO blood group. BS showed a strong significant inverse relation with either von Willebrand ristocetin cofactor (VWF:RCo), von Willebrand antigen (VWF:Ag) or factor VIII procoagulant activity (FVIII:C) measured at time of enrollment, even after adjustment for age, sex and blood group (P < 0.001 for all the four upper quintiles of BS vs. the first quintile, for either VWF:RCo, VWF:Ag or FVIII:C). Higher BS was related with increasing likelihood of VWD, and a mucocutaneous BS (computed from spontaneous, mucocutaneous symptoms) was strongly associated with bleeding after surgery or tooth extraction.

CONCLUSIONS

Quantitative analysis of bleeding symptoms is potentially useful for a more accurate diagnosis of type 1 VWD and to develop guidelines for its optimal treatment.

Linkage analysis in families diagnosed with type 1 von Willebrand disease in the European study, molecular and clinical markers for the diagnosis and management of type 1 VWD

BACKGROUND

von Willebrand disease (VWD) type 1 is a congenital bleeding disorder caused by genetic defects in the von Willebrand factor (VWF) gene and characterized by a reduction of structurally normal VWF. The diagnosis of type 1 VWD is difficult because of clinical and laboratory variability. Furthermore, inconsistency of linkage between type 1 VWD and the VWF locus has been reported.

OBJECTIVES

To estimate the proportion of type 1 VWD that is linked to the VWF gene.

PATIENTS AND METHODS

Type 1 VWD families and healthy control individuals were recruited. An extensive questionnaire on bleeding symptoms was completed and phenotypic tests were performed. Linkage between VWF gene haplotypes and the diagnosis of type 1 VWD, the plasma levels of VWF and the severity of bleeding symptoms was analyzed.

RESULTS

Segregation analysis in 143 families diagnosed with type 1 VWD fitted a model of autosomal dominant inheritance. Linkage analysis under heterogeneity resulted in a summed lod score of 23.2 with an estimated proportion of linkage of 0.70. After exclusion of families with abnormal multimer patterns the linkage proportion was 0.46. LOD scores and linkage proportions were higher in families with more severe phenotypes and with phenotypes suggestive of qualitative VWF defects. About 40% of the total variation of VWF antigen could be attributed to the VWF gene.

CONCLUSIONS

We conclude that the diagnosis of type 1 VWD is linked to the VWF gene in about 70% of families, however after exclusion of qualitative defects this is about 50%.

The discriminant power of bleeding history for the diagnosis of type 1 von Willebrand disease: an international, multicenter study

OBJECTIVE

The aim of this study was the validation of the criteria defining a significant mucocutaneous-bleeding history in type 1 von Willebrand disease (VWD).

SUBJECTS AND METHODS

To avoid selection bias, 42 obligatory carriers (OC) of type 1 VWD were identified from a panel of 42 families with type 1 VWD enrolled by 10 expert centers. OC were identified by the presence of an offspring and another first degree relative with type 1 VWD (affected subjects, AFF). A standardized questionnaire was administered to evaluate hemorrhagic symptoms at the time of first examination, using a bleeding score ranging from 0 (no symptom) to 3 (hospitalization, replacement therapy, blood transfusion). Sensitivity, specificity, diagnostic likelihood ratios, positive and negative predictive values for the diagnosis of type 1 VWD were calculated from the data collected in OC and in 215 controls.

RESULTS

Having at least three hemorrhagic symptoms or a bleeding score of 3 in males and 5 in females was very specific (98.6%) for the bleeding history of type 1 VWD, although less sensitive (69.1%). None of the misclassified OC had life-threatening bleeding episodes after diagnosis.

CONCLUSIONS

We suggest that the use of a standardized questionnaire and bleeding score may be useful for the identification of subjects requiring laboratory evaluation for VWD.

Advances in the therapy of von Willebrand disease

von Willebrand disease (vWD) is a very common autosomal inherited bleeding disorder, caused by a quantitative deficiency or a qualitative structural defect of von Willebrand factor (vWF). Two main therapeutic options are available for the treatment of spontaneous bleeding episodes and for prevention of bleeding: desmopressin (DDAVP) and replacement therapy with plasma products. DDAVP is the treatment of choice for most patients with type 1 vWD. In patients with the type 3 disease and in most subjects with type 2 disease, DDAVP alone is ineffective or contraindicated, and it is usually necessary to switch to plasma concentrates containing both factor VIII (FVIII) and vWF. Concentrates subjected to virucidal treatment (e.g. solvent/detergent treatment) during manufacture should always be used in preference to cryoprecipitate. A recombinant vWF concentrate is now undergoing preclinical development and preliminary data suggest it possesses good haemostatic function and may correct the bleeding in vWD after its administration in several animal models. Although treatment of vWD is relatively simple (assuming access to even basic laboratory facilities), actual diagnosis is often far from straightforward, and the patients should be well characterized phenotypically to tailor the treatment to the different types and subtypes of the disease. It is probably wise to refer samples for the characterization to expert laboratories.

Single-dose ciprofloxacin versus 3 days of norfloxacin in uncomplicated urinary tract infections in women

A double-blind, randomized controlled study to evaluate the efficacy and safety of a single dose of 500 mg of ciprofloxacin versus 3 days 400 mg twice-daily of norfloxacin in uncomplicated urinary tract infection in women was designed. Patients underwent four visits: baseline, and at 3, 7 and 28 days. The main efficacy variables were clinical and microbiological outcome at day 7. Analyses on both valid patients and intention-to-treat populations were performed. Two hundred and twenty-six patients (114 receiving ciprofloxacin and 112 receiving norfloxacin) were considered valid for efficacy evaluation. Bacteriologic cure was 91.2% in the ciprofloxacin group and 91.9% in the norfloxacin group. Clinical resolution was 91.2 and 93.8%, respectively. Both treatments were equally efficacious (P = 0.016).

Type 2B von Willebrand's disease due to Val1316Met mutation. Heterogeneity in the same sibship

An analysis was conducted in four members of the same family, two of whom had a history of severe bleeding associated with type 2B von Willebrand's disease (VWD) which, although found to be due to the same mutation, nevertheless exhibited different phenotype patterns in the two subjects involved. Von Willebrand's factor (VWF) multimers were assayed with high- and low-resolution sodium dodecyl sulfate (SDS) agarose gels. The patients were studied before and after intravenous administration of desmopressin (DDAVP) at doses of 0.4 microg/kg body weight. Automatic sequencing techniques were used to analyze VWF gene exon 28. The propositus presented with mild basal thrombocytopenia with ristocetin-induced platelet aggregation (RIPA) at low concentrations of ristocetin. He had a very prolonged bleeding time (BT), and his plasma VWF was found to be lacking in large and intermediate multimers. Thrombocytopenia was observed to intensify transiently after the administration of DDAVP. The propositus' mother, in contrast, presented reduced RIPA while in a basal state, with only partial loss of the high molecular weight VWF multimers. Although she had a very prolonged BT, her platelet count was borderline. Transient correction of BT and a decrease in the platelet count were observed after administration of DDAVP and RIPA was observed at low concentrations of ristocetin. Exon 28 sequencing revealed a G4196A-->Val1316Met mutation in both patients. No other abnormality was detected within this exon. Val1316Met has been reported in type 2B VWD. In conclusion, in the family presented here, the phenotype pattern in one patient was typical of type 2B VWD, whereas the pattern in his mother was closer to type 2A VWD. After administration of DDAVP, however, a type 2B phenotype could be clearly attributed to both, indicating that this drug can be a useful tool for elucidating ambiguous phenotypes.

Immune tolerance treatment in haemophilia patients with inhibitors: the Spanish Registry

We present a retrospective study of immune tolerance treatment (ITT) carried out in 42 Spanish haemophiliac patients. Most of the patients were high responders (39/42), with a median maximum titre of 67 Bethesda units (BU) (range 6-2984). The median inhibitor titre at the start the ITT was 11 BU (range 1-256 BU) and the median age of the patients was 7 years (range 0-57). The mean factor dosage was 140 IU kg bodyweight(-1) day(-1) (range 25-500). In most of the ITTs, plasma-derived factor concentrate of intermediate and high purity was used. The inhibitor was eradicated in 26/38 (68%) of the patients who completed the treatment and two patients changed their status from high to low responders. Multivariate logistic regression analysis showed that three significant variables were associated with the highest probability of success: (i) the use of low factor doses for ITT (< or = 100 IU kg(-1) day(-1); P = 0.0106; 95% CI 0.000289-0.342); (ii) a titre of < 10 BU at start of ITT (P = 0.0286; 95% CI 0.00253-0.7189) and (iii) a lower maximum titre (P = 0.0214; 95% CI 0.98-0.9994).

A transcriptional insulator at the imprinted H19/Igf2 locus

Igf2 and H19 exhibit parent-of-origin-specific monoallelic expression. H19 is expressed from the maternal chromosome and Igf2 from the paternal. The two genes share enhancer elements and monoallelic expression of both genes is dependent on cis-acting sequences upstream of the H19 promoter. In this work we examine the mechanisms by which this region silences the maternal Igf2 allele and we demonstrate that deletion of this region can result in high levels of activation of both H19 and Igf2 from a single chromosome. Moreover, by inserting this cis element between a promoter and its enhancer at a heterologous position, we demonstrate that the sequences carry both insulator activity and the ability to be stably imprinted. We also characterize the insulator in vitro and show that it is neither enhancer nor promoter specific.

A transcriptional insulator at the imprinted H19/Igf2 locus

Igf2 and H19 exhibit parent-of-origin-specific monoallelic expression. H19 is expressed from the maternal chromosome and Igf2 from the paternal. The two genes share enhancer elements and monoallelic expression of both genes is dependent on cis-acting sequences upstream of the H19 promoter. In this work we examine the mechanisms by which this region silences the maternal Igf2 allele and we demonstrate that deletion of this region can result in high levels of activation of both H19and Igf2 from a single chromosome. Moreover, by inserting thiscis element between a promoter and its enhancer at a heterologous position, we demonstrate that the sequences carry both insulator activity and the ability to be stably imprinted. We also characterize the insulator in vitro and show that it is neither enhancer nor promoter specific.

Mobile robots in industrial environments

It is known that mobile robot applications have a preponderant role in industrial and social environments and, more specifically, helping human beings in carrying out difficult tasks in hostile environments. From teleoperated systems to autonomous robots, there is a wide variety of possibilities requiring a high technological level. Many concepts such as perception, manipulator design, grasping, dynamic control, etc. are involved in the field of industrial mobile robots. In this context, human–robot interaction is one of the most widely studied topics over the last few years together with computer vision techniques and virtual reality tools. In all these technical fields, a common goal is pursued, i.e., robots to come closer to human skills. In this paper, first some important research projects and contributions on mobile robots in industrial environments are overviewed. Second, a proposal for classification of mobile robot architectures is described. Third, results achieved in two specific application areas of mobile robotics are reported. The first is related to the tele-operation of a mobile robot called ROGER by means of a TCP/IP network. The control system of the robot is built up as a distributed system, using distributed object oriented software, CORBA compatible. The second is related to the teleoperation of an underwater robot called GARBI. (Research project co-ordinated with the Polytechnic University of Catalonia (Prof. Josep Amat) and financed by the Spanish Government.) The utility of this kind of prototype is demonstrated in tasks such as welding applications in underwater environments, inspection of dammed walls, etc. Finally, an industrial project involving the use of intelligent autonomous robots is presented showing how the experience gained in robotics has been applied.

Induction of immune tolerance with recombinant factor VIII in haemophilia A patients with inhibitors

We report on 11 patients (nine unrelated and a brother pair) with severe haemophilia A and factor VIII (FVIII) inhibitor, in whom immune tolerance (IIT) was induced with recombinant FVIII (r-FVIII). Their age ranged from 11 months to 47 years. The number of exposure days (ED) at inhibitor detection varied from 11 to 130. Nine of the 11 patients were high responders ¿>10 Bethesda units (BU) with peak inhibitor levels ranging from 10 to 566 BU. The other two were low responders with peak levels between 0.7 and 2 BU. Before inhibitor detection, the patients had been receiving products of various purities. The IIT regimens were very heterogeneous, and the treatment schedule varied from a short period with 50 IU kg-1 every 2 days, followed by 100 IU kg-1 every 2 days and then 220 IU kg-1 daily. The outcome was considered successful when the inhibitor level fell to 0.6 BU or lower after IIT treatment. The outcome overall was successful in nine out of 11 patients (81.8%), with the nine successful cases comprising seven of the nine high responders (77.8%) and the two low responders. Definite failure of IIT was observed in one high responder after two different IIT regimens. A second high responder is still on IIT treatment. All patients in whom IIT was successful are currently receiving r-FVIII on demand or prophylactically at various dosages. Despite the variability of the patient characteristics and the IIT schedules, this study demonstrates that r-FVIII represents an effective alternative for the eradication of inhibitors through IIT.

The problem of diagnosing von Willebrand's disease

Diagnosis of von Willebrand's disease (vWD), particularly vWD Type 1, remains a clinical problem for several aspects. Its definitive diagnosis requires documentation of three factors: bleeding, low levels of qualitatively normal von Willebrand factor (vWF), and inheritance. In the absence of any of these factors the diagnosis may be only merely 'possible', or even unacceptable. Laboratory diagnosis of vWD includes screening tests and confirmatory tests. vWD Types 2 and 3 are relatively easy to diagnose and appear to be genetic disease of a single locus, the vWF gene. As new genetic and possibly non-genetic factors are discovered, the diagnosis of vWD Type 1 may become easier.

Alloantibody from a patient with severe von Willebrand disease inhibits von Willebrand factor-FVIII interaction

The aim of this study was to analyze the ability of an alloantibody from a patient with severe von Willebrand disease (vWD) to interfere with the vWF domain for FVIII, to inhibit factor VIII (FVIII), and to compare it with a rabbit polyclonal antibody. The vWF domain for binding to FVIII was assayed by a method previously described but using recombinant FVIII (r-FVIII, Kogenate), which contains no vWF, instead of Hemofil M (HM). Rabbit or human antibodies towards FVIII (FVIII-Ab) were analyzed using microtiter wells with immobilized r-FVIII through a monoclonal anti-FVIII antibody and an ELISA method. IgG from plasma of a patient with hemophilia A and FVIII inhibitor was used as a positive control. Normal human and rabbit IgGs were included as negative controls. Human vWD alloantibody IgG and the rabbit anti-vWF antibody IgG reacted with immobilized normal vWF, inhibiting its binding to r-FVIII in a dose-dependent manner, which suggests that it is specific. Normal human IgG fraction, as well as nonspecific rabbit IgG, did not interfere with this binding at all. The monoclonal antibody used in this assay to immobilize vWF did not alter this interaction at all. Human vWD alloantibody IgG and the rabbit antibody against vWF showed a partial inhibitory activity to plasma FVIII as well as r-FVIII. The inhibition reached a plateau with residual FVIII activity. FVIII-Ab were not detected in human alloantibody or in rabbit antibody preparations. In contrast, hemophiliac FVIII inhibitor showed FVIII-AB. This human vWD alloantibody behaves like polyclonal heterologous antibodies, and their inhibition of FVIII seems to be nonspecific due to a steric hindrance mechanism provided that both have no FVIII antibodies.

Fluorescence In Situ Hybridization: Trisomy 12 Follow-up In Hairy Cell Leukemia

Peripheral white blood cells from five patients with hairy cell leukemia (HCL) were studied applying fluorescence in situ hybridization (FISH) using heparinized peripheral blood, biotin-labeled chromosome 12-specific α satellite DNA probe and biotin fluorescein-labeled avidin to detect hybridization. This methodology is ideal to investigate the incidence of numerical chromosomal abnormalities of both interphase and metaphase cells. Blood samples from 28 normal subjects were included as control samples. Trisomy 12 was considered to be present when ≥4% of cells had three hybridization spots. Trisomy 12 was detected in three of the five patients at different stages of their evolution. Trisomy 12 was also evident in two patients upon relapse of the HCL. When treatment with interferon alfa (IFN) and steroids was started, clinical and analytical remission were achieved and trisomy 12 disappeared. In one patient trisomy 12 persisted regardless of treatment with IFN and a good clinical evolution. Our results show that trisomy 12 was detected in HCL with FISH at a higher frequency than that previously reported by cytogenetic analysis in either peripheral blood or in cultivated cell lines. These results indicate that the presence of trisomy 12 may be a useful marker for the presence of HCL cells, to check the percentage of trisomic cells and that trisomy 12 is also a useful marker to indicate the activity of the disease.

Antibodies to factor VIII in plasma of patients with hemophilia A and normal subjects

Non-neutralizing factor VIII (FVIII) antibodies (FVIII-Ab) in hemophilia A may be associated with an abnormal clinical response to FVIII concentrates. Patients with FVIII inhibitors may develop noncoagulation FVIII-Ab after the induction of immunotolerance. Natural FVIII-Ab may be detected in the plasma of some healthy subjects. The aim of this study was to analyze the presence of FVIII-Ab in the plasma of 53 normal blood donors and 124 patients with hemophilia A (18 patients had a previous history of FVIII inhibitor, but only 12 had inhibitor at the moment this study was performed). FVIIII inhibitor was measured using the Bethesda method. FVIII-Ab were analyzed by a specific ELISA assay using purified FVIII from a monoclonal concentrate and a standard plasma containing 26 Bethesda units (BU) of FVIII inhibitor. Purified FVIII was used to coat wells of a microtiter plate and was incubated with dilutions of plasma to be tested. Bound human IgG FVIII-Ab were detected by incubation with polyclonal sheep anti.human IgG alkaline phosphatase conjugate, and the OD405 was quantitated. A linear fit was obtained (by plotting FVIII-Ab positivity [OD 405nm] versus BU titer) when serial dilutions of this standard inhibitor plasma, containing titers of 0.5 BU or higher, were used. Four different levels of FVIII-Ab positivity [OD 405nm] were distinguished in this assay: Negative levels (-) were obtained with dilutions of the standard inhibitor containing < 0.5 BU. Mild levels (+) were obtained with dilutions of 0.5-5 BU. Moderate levels (+2) were obtained for dilutions ranging from 5-25 BU. Maximum positivity (+3) was obtained for dilutions of titers > 25 BU. FVIII-Ab positivity was detected in eight of the normal subjects (15%): three were found to be moderately positive (+2) and five mildly positive (+). No inhibitory activity was detectable when whole plasma was used. All the hemophilic patients with a presence of FVIII inhibitor at the time of the study were found to be positive for FVIII-Ab. In addition, the level of positivity correlated with the corresponding BU. Four of the six patients who had a history of inhibitory were negative and two positive. Twenty additional patients (16.12%) in whom no inhibitory activity was detected were found to be positive for FVIII-Ab: 16 + and four +2. The mean age of patients with FVII-Ab positivity was significantly higher than that of patients of the FVIII-Ab negative group (p < 0.005). In conclusion, FVIII-Ab positivity in patients with hemophilia A was 17.7% higher than the level of positivity detected by an inhibitory assay. We propose that this method for FVIII-Ab analysis could be used for patients with hemophilia A, at least to complement the functional inhibitor assay. FVIII recovery or half-life should be assessed in patients who test positive for FVIII-Ab and who show no evidence of inhibitor.

Hemophilia A or von Willebrand disease?

Seven members of the same family were studied on several occasions due to a history of hemorrhages. The propositus, a 12-year-old boy, his sister, one brother, and their father all had a low plasma factor VIII (FVIII) level. Von Willebrand factor (vWF) activity, vWF multimeric analysis, and vWF factor domain for binding to FVIII were normal in all seven subjects. The sister had a normal 46XX karyotype. The study of two intragenic restriction fragment length polymorphisms (RFLPs) and two closely linked, highly polymorphic extragenic markers showed a phenotypic expression of mild hemophilia A, which suggests that the sister of the propositus is homozygous or compound heterozygous at the hemophilia A locus. She would have inherited two hemophilic genes: one from her carrier mother and the other from her father, a mild hemophiliac.