Leonard Kaufman

Leonard Kaufman
Vrije Universiteit Brussel | VUB · Biomedical Statistics and Informatics (BISI)

PhD in Mathematics

About

192
Publications
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Publications

Publications (192)
Article
Introduction: The liver plays a central role in thyroid hormone metabolism, transport, and clearance. A normal function of both the thyroid gland and the liver is therefore necessary to maintain normal thyroid hormone levels and action. Data regarding thyroid function in patients with liver cirrhosis are scarce and variable. The most consistent fi...
Article
Recombinant human C1 inhibitor (rhC1INH) for on demand treatment of hereditary angioedema, is purified from milk of transgenic rabbits. It contains low amounts (<0.002%) of host-related impurities (HRI), which could trigger hypersensitivity reactions in patients with rabbit allergy (RA) and/or cow’s milk allergy (CMA).
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OBJECTIVE Immune intervention trials in recent-onset type 1 diabetes would benefit from biomarkers associated with good therapeutic response. In the previously reported randomized placebo-controlled anti-CD3 study (otelixizumab; GlaxoSmithKline), we tested the hypothesis that specific diabetes autoantibodies might serve this purpose.RESEARCH DESIGN...
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OBJECTIVE Previous work has shown a correlation between β-cell number in cultured islet cell grafts and their ability to induce C-peptide secretion after intraportal implantation in C-peptide-negative type1 diabetic patients. In this cross-sectional study, we examined the minimal functional β-cell mass (FBM) in the implant that induces metabolic im...
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Background Recombinant C1 inhibitor (rhC1INH) is a novel therapeutic option for the treatment of acute angioedema attacks in patients with hereditary angioedema (HAE). The amino acid sequence of rhC1INH is identical to that of endogenous C1INH. However, any recombinant protein may elicit antibodies against the protein and/or host related impurities...
Article
Hereditary angioedema (HAE) results from a genetic deficiency of C1-inhibitor. Two similar independent, randomized, saline controlled, double-blind studies were conducted to evaluate the efficacy and safety of recombinant human C1-inhibitor (rhC1INH) as a treatment of acute angioedema attacks in patients with HAE. Analysis of pooled study results....
Article
A new non hierarchical clustering procedure is used to evaluate an existing classification of iron meteorites. It is shown that the classification obtained resembles the existing classification to a large degree. This confirms the consistency of both the clustering method and the existing classification. The principal disagreement between the exist...
Article
Aims: Most smokers who quit smoking usually relapse. Smoking relapse prevention programs are thus needed and their optimal content and duration should be therefore studied. The present study aimed to compare the efficacy of two relapse prevention programs designed for subjects who reported to be abstinent after a smoking cessation program and to as...
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Aims/hypothesis The aim of the study was to examine the 48 month outcome of treating recent-onset type 1 diabetic patients for 6 days with humanised CD3-antibody, ChAglyCD3. Methods Eighty patients, aged 12–39 years, were recruited for a phase 2 multicentre trial and randomised to placebo (n = 40) or ChAglyCD3 (n = 40) treatment by a third party...
Article
Patients with genotype 4 (G4) chronic hepatitis C from the Middle East respond better to treatment than genotype 1 (G1) patients. There are few data on the response rates to treatment of G4 patients living in Western Europe. Many G4 patients in Belgium originate from Central Africa, and their response to treatment seems lower. We analysed the data...
Book
The Wiley-Interscience Paperback Series consists of selected books that have been made more accessible to consumers in an effort to increase global appeal and general circulation. With these new unabridged softcover volumes, Wiley hopes to extend the lives of these works by making them available to future generations of statisticians, mathematician...
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The metabolic outcome of islet cell transplants in type 1 diabetic patients is variable. This retrospective analysis examines whether differences in recipient characteristics at the time of transplantation are correlated with inadequate graft function. Thirty nonuremic C-peptide-negative type 1 diabetic patients had received an intraportal islet ce...
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Repolarization abnormalities in the inferior-lateral leads in Brugada syndrome (BS) have not been systematically investigated. 280 patients (age, 41+/-18 years; 168 males) with BS were screened for inferior-lateral repolarization abnormalities. The repolarization abnormalities were classified either as early repolarization pattern or coved > or = 2...
Article
Recent studies indicate that medication resistant depressed patients can be successfully treated by a series of sessions of High Frequency repetitive Transcranial Magnetic Stimulation (HF-rTMS), delivered on the left dorsolateral prefrontal cortex (DLPFC). However, changes in subjectively experienced mood give only limited insight into the underlyi...
Chapter
Short Description of the Method How to Use the Program MONA Examples More on the Algorithm and the Program Related Methods and References
Article
Recently aromatase inhibitors have become a standard care as an adjuvant treatment for many postmenopausal patients with hormone receptor positive early breast cancer. Adjuvant letrozole was made available either immediately postoperative, after 2-3 years of tamoxifen, or as an extended treatment after 5 years of tamoxifen. Between October 2003 and...
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Currently used diagnostic manoeuvres at the electrophysiology study do not always allow for consistent identification of atrial tachycardia (AT), either because of inapplicability of the technique or because of low predictive value and specificity. The aim of this study was to determine whether overdrive atrial pacing during paroxysmal supraventric...
Article
The treatment of diffuse large B-cell lymphoma with chemotherapy was retrospectively evaluated in 348 patients who had received at least three cycles of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-like, ACVBP (doxorubicin, cyclophosphamide, vindesine, bleomycin, and prednisone)-like or CHVmP-BV (cyclophosphamide, hydroxorubici...
Article
The transurethral resection in saline system uses bipolar energy for transurethral prostate resection, thus, avoiding the need for glycine irrigation and its associated complications. We compared the clinical efficacy and safety of bipolar transurethral resection in saline and of monopolar transurethral prostate resection for symptomatic benign pro...
Article
Resolution was defined as achieving the severity component of the remission criteria (simultaneous ratings of mild or less on 8 of the PANSS items evaluating the core symptoms of schizophrenia). Analysis of a 6-week open label study with olanzapine 5-20 mg in 306 patients with acute exacerbation, shows resolution to be a clinically meaningful measu...
Article
Prevention trials of type I diabetes are limited by recruitment of individuals at high risk of the disease. We investigated whether demographic and biological characteristics can identify rapid progressors among first-degree relatives of known patients at intermediate (< 10%) 5-year risk. Diabetes-associated antibodies, random proinsulin : C-peptid...
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A strategy combining human papillomavirus general primer (mainly the PGMY primers)-directed PCR sequencing and type-specific PCR is presented. DNA samples were first tested in general primer-mediated PCR. The amplified fragments of positive samples after ethidium bromide-stained DNA gel analysis were further sequenced, and corresponding DNA samples...
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Full-text available
A strategy combining human papillomavirus general primer (mainly the PGMY primers)-directed PCR sequencing and type-specific PCR is presented. DNA samples were first tested in general primer-mediated PCR. The amplified fragments of positive samples after ethidium bromide-stained DNA gel analysis were further sequenced, and corresponding DNA samples...
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Full-text available
Type 1 diabetes mellitus is a T-cell-mediated autoimmune disease that leads to a major loss of insulin-secreting beta cells. The further decline of beta-cell function after clinical onset might be prevented by treatment with CD3 monoclonal antibodies, as suggested by the results of a phase 1 study. To provide proof of this therapeutic principle at...
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Amyloid-containing (A+) islets are characteristic for type-2 diabetes (T2D), but their abundance seems variable among patients. It is unclear whether the distribution of A+ islets follows a certain pattern or occurs randomly throughout the pancreatic organ. We investigated the topography of A+ islets in eight pancreata of T2D patients and eight sex...
Article
Although antimony electrodes are by far the most popular for performing oesophageal pH monitoring, there are few data comparing the accuracy of glass and antimony electrodes. Therefore, we tested the accuracy of both electrodes in the prediction of oesophagitis. pH monitoring using a glass electrode and an antimony electrode was performed in 60 dis...
Article
The purpose of this study was to determine which patient characteristics are predictive of outcome before pelvic floor muscle training for stress urinary incontinence. This was an observational study at a single-center outdoor patient clinic in Brussels, Belgium, that comprised 447 women, aged 26 to 80 years (mean, 52.7 years), who had urinary stre...
Article
Unlabelled: Acid reflux and/or oesophagitis may be responsible for inconsolable crying in infants. We evaluated prospectively the presence of acid reflux disease, oesophagitis and the accuracy of pH monitoring in the prediction of oesophagitis in a population of irritable infants. A 24-h oesophageal pH monitoring with a glass electrode and an uppe...
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Type 1 diabetes arises from an interplay between environmental and genetic factors. The reported seasonality at diagnosis supports the hypothesis that currently unknown external triggers play a role in the onset of the disease. We investigated whether a seasonal pattern is observed at diagnosis in Belgian Type 1 diabetic patients, and if so whether...
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Acid reflux and/or esophagitis may be responsible for inconsolable crying in infants. We evaluated prospectively the presence of occult acid reflux disease, esophagitis and the accuracy of pH monitoring in the prediction of esophagitis in a population of distressed infants. A 24-hour esophageal pH monitoring with an antimony electrode and an upper...
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The association between positive thyroid antibodies and an increased miscarriage rate in pregnancies after assisted reproduction technology (ART) remains controversial. We wanted to clarify this issue by performing a prospective cohort study in 234 women by systematically screening for thyroid peroxidase antibodies (TPO-Ab), serum TSH, and free T(4...
Article
Aim: To determine whether oesophageal pH monitoring in infants induces changes in daily activity and feeding, and with the help of a questionnaire to evaluate how parents perceive pH monitoring. Methods: The parents of 100 children, consecutively referred for oesophageal pH monitoring, were asked by one of the authors (A.A.) to respond to a stan...
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Serum levels of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor (TNF)-alpha were frequently measured during the first 30 days after allogeneic bone marrow transplantation (BMT) in 84 consecutive adult patients. Major transplant-related complications (MTCs) occurred in 33% of cases and included veno-occlusive liver disease, idio...
Article
Several studies have focused on factors determining recurrence and survival rate after curative resection of colorectal liver metastases (LM). Data are lacking with regard to patterns of failure indicating where and when recurrences arise. One-hundred-and-five consecutive patients [F/M: 31/74; mean age 61 years (range 36-80 y)] with primary colorec...
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Multiple islet autoantibody positivity is currently believed to best predict progression to Type I (insulin-dependent) diabetes mellitus. We compared its predictive value with that of positivity for a particular type of islet autoantibody, directed against the IA-2 antigen. Autoantibodies against islet cell cytoplasm (ICA), insulin (IAA), GAD (GADA...
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We monitored levels of C-reactive protein (CRP) in 96 consecutive adult allogeneic BMT patients (age 15-50 years) transplanted in our unit. Major transplant-related complications (MTC) occurred in 32% of cases and included: hepatic veno-occlusive disease, pneumonitis, severe endothelial leakage syndrome and >II acute GVHD. Transplant-related mortal...
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We investigated inaugural disease phenotype in relation to the presence or absence of diabetes-associated autoantibodies and human leukocyte antigen (HLA) DQ risk genotypes in adult-onset diabetic patients. Blood samples and questionnaires were obtained from 1584 recent-onset Belgian Caucasian patients (age 15-39 yr at diagnosis of primary diabetes...
Article
The goal of this study was to evaluate biophysically and clinically the hand skin of nurses working in the operating room in comparison with the hand skin of a control group of female administrative employees. 19 nurses and 14 employees were included in this trial. Transepidermal water loss (TEWL) and stratum corneum (SC) hydration were evaluated o...
Article
Nickel (Ni)-induced allergic contact dermatitis (ACD) was performed in human volunteers to study the role of moisturisers in preventing ACD-related skin barrier damage. 15 Ni-sensitive females (mean age: 29.5 years; range: 23-38) were included. On days 1, 21, 24 and 26, TEWL, stratum corneum (SC)-capacitance and clinical score were evaluated on fou...
Article
In this study we used the nickel contact allergy patch (CAP) test to investigate the effect of topical corticosteroids on allergic contact dermatitis (ACD). On day 1, three CAP tests were applied for 48 h on the forearms of 20 female volunteers with a known nickel ACD. CAP of the right forearm contained 5% nickel, and of the left forearm physiologi...
Article
In our institute, the oestrogen and progesterone receptors of breast cancer samples are analyzed by biochemistry and immunohistochemistry. The purpose of this study is to evaluate and compare both techniques and establish whether one of them should be used in preference to the other. The probability of getting a positive or negative result with eac...
Article
Despite international agreements and recommendations regarding cancer pain therapy, the effectiveness of pain treatment is still a major problem even in Western countries. Part of the problem is that physicians and nurses often lack knowledge of methods for the assessment and treatment of cancer pain and may have many rigid beliefs and attitudes. T...
Article
Standard distal esophageal pH monitoring data are sometimes within normal ranges in children with clinically suspected gastroesophageal reflux disease. Therefore, the authors hypothesized that the amount of acid reflux reaching the proximal esophagus may be greater in some subgroups of patients than in healthy controls or in other subgroups of pati...
Article
Nickel (Ni) allergic contact dermatitis (ACD) alters the skin barrier. Our aim was to compare the efficacy of combination therapies on ACD, using a topical corticosteroid and a corneotherapy agent (barrier cream), with that of a single therapy with corticosteroids. On day 1, 3 Ni test patches were applied on each forearm of 14 Ni-patch-test-positiv...
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OBJECTIVE - To investigate whether the presence of antibody markers at diagnosis could help predict the rapid decrease in residual beta-cell function noted in some, but not all, patients with recent-onset type 1 diabetes. RESEARCH DESIGN AND METHODS - We measured random C-peptide levels (radioimmunoassay); islet cell cytoplasmic antibodies (ICA) (...
Article
To prospectively study the relationship of quantitative ultrasound of the calcaneus with anthromopometric variables and with bone mineral density (BMD) assessed at the level of the calcaneus as well as at other sites. Osteosonography of the non-dominant calcaneus was performed in 135 menopausal women, using a DTU-one device with parametric imaging....
Article
Gram-positive bacteremia (GPB) is an increasing infection after allogeneic bone marrow transplantation (BMT). Our purpose was to identify risk factors for GPB, to evaluate its impact on early mortality and morbidity, and to compare prophylactic with empirical intravenous vancomycin. We studied 89 consecutive BMTs in adult patients. Early GPB occurr...
Article
Middle meatal samples were obtained from 52 carefully selected healthy adults. In 75 per cent of the test subjects bacterial organisms were cultured. However, growth was often poor and the predominant species suggest a commensal flora: coagulase-negative staphylococci were retrieved from 35 per cent, Corynebacterium sp. from 23 per cent and Staphyl...
Article
Middle meatal samples were obtained from 52 carefully selected healthy adults. In 75 per cent of the test subjects bacterial organisms were cultured. However, growth was often poor and the predominant species suggest a commensal flora: coagulase-negative staphylococci were retrieved from 35 per cent, Corynebacterium sp. from 23 per cent and Staphyl...
Article
Nitrates may be used for pharmacological stimulation during tilt testing for the diagnosis of vasovagal syncope. In this study we assessed the diagnostic value of intravenous nitrates during tilt testing in patients with a typical history of vasovagal syncope. Twenty patients and 23 controls were tilted at 700 for a maximum duration of 30 minutes....
Article
The aim of the study was to assess the effectiveness of worksite group counselling interventions designed to prevent smoking relapse after abstinence has been achieved following 3 months therapy using group support and/or transdermal nicotine replacement therapy. After 3 months, abstinent subjects were randomly allocated either to a counselling gro...
Article
Little is known about the bacteriology of the middle meatus in children. Therefore, middle meatal samples were obtained from 50 children who underwent adenoidectomy or adenotonsillectomy, while a group of 50 children submitted to minor non-ENT surgical procedures, were used as a control group. Haemophilus influenzae, Moraxella catarrhalis and Strep...
Article
Controversy exists about the optimal surgical resection for lower third rectal carcinoma. The aim of this retrospective study was to analyse whether the type of surgery is a significant predictor of outcome after curative surgery alone. Eighty-two consecutive patients underwent abdominoperineal rectum excision (APRE, 41 patients) or sphincter-savin...
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Patterns of C-reactive protein (CRP) release were derived from frequent CRP measurements in a cohort of 66 consecutive patients receiving allogeneic bone marrow transplants (BMT) in our unit. Based on a retrospective study of clinical events occurring within the first 40 days after BMT, patients with major transplant-related complications (MTC+ gro...
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In a population of 100 children with suspected intracranial neurological disease, the overall prevalence of sinusitis signs on magnetic resonance images (MRI) is 45%. This figure exceeds the adult prevalence of 39%, while the nature of the lesions is more severe in children. Furthermore, paediatric sinuses seem to be affected according to a differe...
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A meta-analysis of clinical trials of antihistamines was performed to assess the risk-benefit ratio of this therapeutic class in asthma. Double-blind randomized placebo-controlled trials assessing lung function changes under repeated use of antihistamine in adult asthma were selected, and the quality of studies was scored. Morning peak expiratory f...
Article
To study the prognostic value of the prostate-specific antigen (PSA) response and its relationship with other initial prognostic factors during the treatment of advanced prostatic carcinoma with total androgen blockade. Five hundred forty-six patients with advanced loco-regional (M0) or distant metastatic (M1) prostatic carcinoma treated with fluta...
Article
To investigate the association of GAD (65-kDa) autoantibodies (GAD65-Abs) and IA-2 autoantibodies (IA-2-Abs) with human leukocyte antigen (HLA)-DQ and insulin gene (INS) risk markers in patients with recent-onset IDDM and their siblings. Blood was sampled from 608 recent-onset IDDM patients and 480 siblings, aged 0-39 years and consecutively recrui...
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Effects of antihistamines in adult asthma: a meta-analysis of clinical trials. E. Van Ganse, L. Kaufman, M.P. Derde, J.C. Yernault, L. Delaunois, W. Vincken. ©ERS Journals Ltd 1997. ABSTRACT: A meta-analysis of clinical trials of antihistamines was performed to assess the risk-benefit ratio of this therapeutic class in asthma. Double-blind randomiz...
Article
A structured psychiatric interview, forming part of a global psychopathological approach, revealed higher prevalence rates of current and lifetime psychiatric disorders and a higher degree of psychiatric comorbidity in patients with chronic fatigue syndrome (CFS) than in a medical control group. In contrast to previous studies, a very high prevalen...
Article
Physical fatigability and avoidance of physically demanding tasks in chronic fatigue syndrome (CFS) were assessed by the achievement or nonachievement of 85% of age-predicted maximal heart rate (target heart rate, THR) during incremental exercise. The association with functional status impairment, somatization, and psychopathology was examined. A s...