659 research outputs found
Radiolabeled humanized anti-CD3 monoclonal antibody visilizumab for imaging human T-lymphocytes
Visilizumab is an IgG2 humanized monoclonal antibody (mAb) characterized by non-FcĂÂłR binding and specific to the CD3 antigen, expressed on more than 95% of circulating resting T-lymphocytes and on activated T-lymphocytes homing in inflamed tissues. We hypothesized that the use of a radiolabeled anti-CD3 antibody might serve as a diagnostic tool for imaging T-cell traffic and lymphocytic infiltration of tissues and organs affected by autoimmune diseases. Here we describe the results of in vitro and animal experiments with 99mTc-succinimidyl-6-hydrazinonicotinate hydrochloride (SHNH)-visilizumab. Methods: For mAb labeling, we used a 2-step method with a heterobifunctional linker SHNH. Several titrations were performed to obtain the best labeling efficiency. In vitro quality controls included stability assay, cysteine challenge, sodium dodecyl sulfate polyacrylamide gel electrophoresis, binding assay, and immunoreactivity assay. In vivo studies by high-resolution images were performed at 6 and 24 h after the injection of 99mTc-SHNH-visilizumab. These included cell-targeting experiments in BALB/c mice xenografted subcutaneously with an increasing number of HuT78 cells in the leg and displaced with an excess of cold antibody. We also studied irradiated severe combined immunodeficient (SCID) mice reconstituted with human peripheral blood mononuclear cells (hPBMCs) and injected with 99mTclabeled visilizumab or control mAb. After dynamic imaging for 3 h, major organs were removed, counted, and processed for immunohistologic examination. Results: Visilizumab was labeled with HYNIC with high labeling efficiency (>90%) and high specific activity (SA; 10,360-11,100 MBq/mg), with retained biochemical integrity and in vitro binding activity to CD3-positive cells. The in vivo targeting experiment showed a proportional increase of specific uptake with the number of injected cells, both at 6 and at 24 h, and the in vivo competition study demonstrated more than 60% decreased uptake after an excess of unlabeled antibody. In SCID mice, hPBMCs in different tissues were detected by 99mTc-labeled visilizumab and confirmed by histology. Conclusion: Visilizumab can be efficiently labeled with 99mTc with high efficiency and SA and could be a valuable tool for the study of human T-lymphocyte trafficking and lymphocytic infiltration of tissues and organs. Copyright Ă© 2009 by the Society of Nuclear Medicine, Inc
Identification of viable myocardium in patients with chronic coronary artery disease and left ventricular dysfunction: role of MRI.
Nineteen patients (16 men and 3 women, mean age 51 years) with previous anterior myocardial infarction and severe stenosis (> or = 90%) of the left anterior descending coronary artery were studied by magnetic resonance imaging (MRI) without and with contrast media to verify the capability of MRI in identifying viable myocardium in areas of severe systolic dysfunction. In corresponding left ventricular segments, a comparison was made between regional signal intensities (SI) determined on MRI images before and 4, 8, 12, and 30 minutes after administration of paramagnetic contrast media (gadolinium diethylenetriaminepentaacetic acid, 0.4 mmol/kg intravenously) and metabolic parameters determined by iodine 123 phenylpentadecanoic acid (IPPA) scintigraphy. The SI and the time of maximum postcontrast enhancement were analyzed by dividing the left ventricle into 11 segments. Each segment was classified as normal (group 1, n = 116), hibernating (group 2, n = 50), or necrotic (group 3, n = 43) on the basis of the IPPA washout rate (> 30%, 10% to 30%, and < 10%, respectively). Regional SI demonstrated significant differences in absolute values at 12 minutes (group 3: 1.62 +/- 0.58 vs group 1: 1.32 +/- 0.52, p < 0.01, and vs group 2: 1.34 +/- 0.48, p < 0.05) and at 30 minutes (group 3: 1.71 +/- 0.47 vs group 1: 1.21 +/- 0.55, p < 0.01, and vs group 2: 1.49 +/- 0.57, p < 0.05) and in temporal distribution. These results suggest that MRI has a potential role in differentiating viable from necrotic myocardium in patients with chronic severe systolic dysfunction
Recommendations for neonatologists and pediatricians working in first level birthing centers on the first communication of genetic disease and malformation syndrome diagnosis: consensus issued by 6 Italian scientific societies and 4 parentsâ associations
Background: Genetic diseases are chronic conditions with relevant impact on the lives of patients and their families. In USA and Europe it is estimated a prevalence of 60 million affected subjects, 75% of whom are in developmental age. A significant number of newborns are admitted in the Neonatal Intensive Care Units (NICU) for reasons different from prematurity, although the prevalence of those with genetic diseases is unknown. It is, then, common for the neonatologist to start a diagnostic process on suspicion of a genetic disease or malformation syndrome, or to make and communicate these diagnoses. Many surveys showed that the degree of parental satisfaction with the methods of communication of diagnosis is low. Poor communication may have short and long-term negative effects on health and psychological and social development of the child and his family. We draw up recommendations on this issue, shared by 6 Italian Scientific Societies and 4 Parentsâ Associations, aimed at making the neonatologistâs task easier at the difficult time of communication to parents of a genetic disease/malformation syndrome diagnosis for their child. Methods: We used the method of the consensus paper. A multidisciplinary panel of experts was first established, based on the clinical and scientific sharing of the thematic area of present recommendations. They were suggested by the Boards of the six Scientific Societies that joined the initiative: Italian Societies of Pediatrics, Neonatology, Human Genetics, Perinatal Medicine, Obstetric and Gynecological Ultrasound and Biophysical Methodologies, and Pediatric Genetic Diseases and Congenital Disabilities. To obtain a deeper and global vision of the communication process, and to reach a better clinical management of patients and their families, representatives of four Parentsâ Associations were also recruited: Italian Association of Down People, Cornelia de Lange National Volunteer Association, Italian Federation of Rare Diseases, and Williams Syndrome People Association. They worked from September 2019 to November 2020 to achieve a consensus on the recommendations for the communication of a new diagnosis of genetic disease. Results: The consensus of experts drafted a final document defining the recommendations, for the neonatologist and/or the pediatrician working in a fist level birthing center, on the first communication of genetic disease or malformation syndrome diagnosis. Although there is no universal communication technique to make the informative process effective, we tried to identify a few relevant strategic principles that the neonatologist/pediatrician may use in the relationship with the family. We also summarized basic principles and significant aspects relating to the modalities of interaction with families in a table, in order to create an easy tool for the neonatologist to be applied in the daily care practice. We finally obtained an intersociety document, now published on the websites of the Scientific Societies involved. Conclusions: The neonatologist/pediatrician is often the first to observe complex syndromic pictures, not always identified before birth, although today more frequently prenatally diagnosed. It is necessary for him to know the aspects of genetic diseases related to communication and bioethics, as well as the biological and clinical ones, which together outline the cornerstones of the multidisciplinary care of these patients. This consensus provide practical recommendations on how to make the first communication of a genetic disease /malformation syndrome diagnosis. The proposed goal is to make easier the informative process, and to implement the best practices in the relationship with the family. A better doctor-patient/family interaction may improve health outcomes of the child and his family, as well as reduce legal disputes with parents and the phenomenon of defensive medicine
Synthesis and Optimization of the Labeling Procedure of 99mTc-Hynic-Interleukin-2 for In vivo Imaging of Activated T lymphocytes
Introduction: We have previously described the labeling of interleukin-2 (IL2) with 123 I and 99m Tc-N3S. Both radiopharmaceuticals were successfully applied in humans to image several inflammatory lesions and autoimmune diseases characterized by tissue infiltrating lymphocytes expressing the IL2 receptor (CD25). However, both radiopharmaceuticals had some specific disadvantages, such as cost and time of synthesis
Investigating the association between obesity and asthma in 6- to 8-year-old Saudi children:a matched case-control study
Background: Previous studies have demonstrated an association between obesity and asthma, but there remains considerable uncertainty about whether this reflects an underlying causal relationship. Aims: To investigate the association between obesity and asthma in pre-pubertal children and to investigate the roles of airway obstruction and atopy as possible causal mechanisms. Methods: We conducted an age- and sex-matched caseâcontrol study of 1,264 6- to 8-year-old schoolchildren with and without asthma recruited from 37 randomly selected schools in Madinah, Saudi Arabia. The body mass index (BMI), waist circumference and skin fold thickness of the 632 children with asthma were compared with those of the 632 control children without asthma. Associations between obesity and asthma, adjusted for other potential risk factors, were assessed separately in boys and girls using conditional logistic regression analysis. The possible mediating roles of atopy and airway obstruction were studied by investigating the impact of incorporating data on sensitisation to common aeroallergens and measurements of lung function. Results: BMI was associated with asthma in boys (odds ratio (OR)=1.14, 95% confidence interval (CI), 1.08â1.20; adjusted OR=1.11, 95% CI, 1.03â1.19) and girls (OR=1.37, 95% CI, 1.26â1.50; adjusted OR=1.38, 95% CI, 1.23â1.56). Adjusting for forced expiratory volume in 1 s had a negligible impact on these associations, but these were attenuated following adjustment for allergic sensitisation, particularly in girls (girls: OR=1.25; 95% CI, 0.96â1.60; boys: OR=1.09, 95% CI, 0.99â1.19). Conclusions: BMI is associated with asthma in pre-pubertal Saudi boys and girls; this effect does not appear to be mediated through respiratory obstruction, but in girls this may at least partially be mediated through increased risk of allergic sensitisation
Thyroid Cancer Imaging In Vivo by Targeting the Anti-Apoptotic Molecule Galectin-3
Background The prevalence of thyroid nodules increases with age, average 4-7% for the U.S.A. adult population, but it is much higher (19-67%) when sub-clinical nodules are considered. About 90% of these lesions are benign and a reliable approach to their preoperative characterization is necessary. Unfortunately conventional thyroid scintigraphy does not allow the distinction among benign and malignant thyroid proliferations but it provides only functional information (cold or hot nodules). The expression of the anti-apoptotic molecule galectin-3 is restricted to cancer cells and this feature has potential diagnostic and therapeutic implications. We show here the possibility to obtain thyroid cancer imaging in vivo by targeting galectin-3. Methods The galectin-3 based thyroid immuno-scintigraphy uses as radiotracer a specific 99mTc-radiolabeled mAb. A position-sensitive high-resolution mini-gamma camera was used as imaging capture device. Human galectin-3 positive thyroid cancer xenografts (ARO) and galectin-3 knockout tumors were used as targets in different experiments in vivo. 38 mice with tumor mass of about 1 gm were injected in the tail vein with 100 ?Ci of 99mTc-labeled mAb to galectin-3 (30 ?g protein/in 100 ?l saline solution). Tumor images were acquired at 1 hr, 3 hrs, 6 hrs, 9 hrs and 24 hrs post injection by using the mini-gamma camera. Findings Results from different consecutive experiments show an optimal visualization of thyroid cancer xenografts between 6 and 9 hours from injection of the radiotracer. Galectin-3 negative tumors were not detected at all. At 6 hrs post-injection galectin-3 expressing tumors were correctly visualized, while the whole-body activity had essentially cleared. Conclusions These results demonstrate the possibility to distinguish preoperatively benign from malignant thyroid nodules by using a specific galectin-3 radio-immunotargeting. In vivo imaging of thyroid cancer may allow a better selection of patients referred to surgery. The possibility to apply this method for imaging and treatment of other galectin-3 expressing tumors is also discussed
Providing high-quality care remotely to patients with rare bone diseases during COVID-19 pandemic
During the COVID-19 outbreak, the European Reference Network on Rare Bone Diseases (ERN BOND) coordination team and Italian rare bone diseases healthcare professionals created the "COVID-19 Helpline for Rare Bone Diseases" in an attempt to provide high-quality information and expertise on rare bone diseases remotely to patients and healthcare professionals. The present position statement describes the key characteristics of the Helpline initiative, along with the main aspects and topics that recurrently emerged as central for rare bone diseases patients and professionals. The main topics highlighted are general recommendations, pulmonary complications, drug treatment, trauma, pregnancy, children and elderly people, and patient associations role. The successful experience of the "COVID-19 Helpline for Rare Bone Diseases" launched in Italy could serve as a primer of gold-standard remote care for rare bone diseases for the other European countries and globally. Furthermore, similar COVID-19 helplines could be considered and applied for other rare diseases in order to implement remote patients' care
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