Characterization of Radiologists’ Search Strategies for Lung Nodule Detection: Slice-Based Versus Volumetric Displays

The goal of this study was to assess whether radiologists’ search paths for lung nodule detection in chest computed tomography (CT) between different rendering and display schemes have reliable properties that can be exploited as an indicator of ergonomic efficiency for the purpose of comparing different display paradigms. Eight radiologists retrospectively viewed 30 lung cancer screening CT exams, containing a total of 91 nodules, in each of three display modes [i.e., slice-by-slice, orthogonal maximum intensity projection (MIP) and stereoscopic] for the purpose of detecting and classifying lung nodules. Radiologists’ search patterns in the axial direction were recorded and analyzed along with the location, size, and shape for each detected feature, and the likelihood that the feature is an actual nodule. Nodule detection performance was analyzed by employing free-response receiver operating characteristic methods. Search paths were clearly different between slice-by-slice displays and volumetric displays but, aside from training and novelty effects, not between MIP and stereographic displays. Novelty and training effects were associated with the stereographic display mode, as evidenced by differences between the beginning and end of the study. The stereo display provided higher detection and classification performance with less interpretation time compared to other display modes tested in the study; however, the differences were not statistically significant. Our preliminary results indicate a potential role for the use of radiologists’ search paths in evaluating the relative ergonomic efficiencies of different display paradigms, but systematic training and practice is necessary to eliminate training curve and novelty effects before search strategies can be meaningfully compared.     

Langerhans cell histiocytois of the thyroid: a rare disease not to be ignored

Thyroid involvement by Langerhans cell histiocytosis is rare. We report the case of a ten-year old boy who presented with a 5 cm goitre. He was treated for diabetes insipidus 14 months before. Thyroid isotopic scan showed hypoactivity of right lobe and revealed a cold left nodule. The patient was treated by right lobo-isthmectomy with adjuvant corticotherapy and chemotherapy (vinblastine). He is well with 12 months follow-up. Microscopic analysis demonstrated a diffuse infiltrate of thyroid parenchyma by sheets of CD1a positive Langerhans cells associated with lymphocyte foci. This case is remarkable by the abundance of Langerhans cells and scarcity of eosinophils. The diagnosis of thyroid langerhans cell histiocytosis should not be ignored in both children and adult patients.     

Recognition of coxsackievirus A by Enterovirus genus-specific immune and molecular markers in experimentally infected suckling mice

OBJECTIVE: Most of coxsackieviruses A (CV-A) are difficult to isolate in cell culture and are responsible for flask paralysis in suckling mice. The aim of the present work was to analyze the ability of immune and RT-PCR techniques to detect viral components of three different serotypes, CV-A6, CV-A13, and CV-A14, in skeletal muscles of experimentally infected suckling mice. MATERIAL AND METHODS: The antigen detection was done by immunofluorescence technique on trypsinized muscular cells and by immunoperoxidase assay on frozen sections of skeletal muscle, using a monoclonal antibody directed towards a conserved epitope of the VP1 capsid protein among enteroviruses. The nested RT-PCR technique used primers located in the 5' non coding region of viral RNA. RESULTS: The group antigen was present in muscle cells of suckling mice infected by the three serotypes of CV-A which were assayed. Similarly, the muscle specimens were positive by nested RT-PCR. A kinetic study performed with CV-A13 and CV-A14 showed that the RT-PCR assay was positive as soon as 24 h after infection whereas the detection of VP1 antigen and symptoms of flask paralysis were observed only 48 and 72 h after infection, respectively. CONCLUSION: These results show that the tested serotypes of CV-A can be easily detected in muscle specimens of suckling mice by using antigenic and molecular techniques currently available for the diagnosis of enterovirus infections.     

Assessment of Alpha-Fetoprotein in the Diagnosis of Hepatocellular Carcinoma in Middle Eastern Patients

Background  

Alpha-fetoprotein (AFP) levels for the diagnosis of hepatocellular carcinoma (HCC) may vary by geographical region and racial background. No data exists for this test in the Middle Eastern population. In addition, there is limited data on the impact of virological status on AFP levels.     

ATRA and anthracycline-based chemotherapy in the treatment of childhood acute promyelocytic leukemia (APL): A 10-year experience in Tunisia

Reports on childhood APL from developing countries are scarce. We treated 65 APL with two consecutive trials combining ATRA and chemotherapy. Twenty (30.7%) were aged less than 20 years including 11 girls and 9 boys, with a median age of 12 years. Fever at presentation (P = 0.002) and variant APL (P = 0.044) were more frequent in children, while there were no significant difference between children and adults for WBC count, Sanz’s score distribution and additional cytogenetic abnormalities. The CR rate was 95% (19/20) in children and 80% (36/45) in adults (P = 0.13). Differentiation syndrome (DS) was less often observed in children (1/20) than in adults (13/45) (P = 0.031). Two children relapsed and died during salvage therapy, and 2 died in CR from infection and from cardiac failure attributed to anthracyclines, while other children remained alive in CR. With a median follow-up of 4 years, 4-year EFS was 75% in children and 71.1% in adults (P = 0.57), while 4-year OS was 75% in children vs. 73.3% in adults (P = 0.72). Our results suggest that, even in the absence of optimal socio-economic condition, ATRA combined with anthracycline-based chemotherapy gives adequate results in childhood APL, as in adults.     

Safety and efficacy of AAV-mediated calpain 3 gene transfer in a mouse model of limb-girdle muscular dystrophy type 2A.

Calpainopathy (limb-girdle muscular dystrophy type 2A, LGMD2A) is a recessive muscular disorder caused by deficiency in the calcium-dependent cysteine protease calpain 3. To date, no treatment exists for this disease. We evaluated the potential of recombinant adeno-associated virus (rAAV) vectors for gene therapy in a murine model for LGMD2A. To drive the expression of calpain 3, we used rAAV2/1 pseudotyped vectors and muscle-specific promoters to avoid calpain 3 cell toxicity. We report efficient and stable transgene expression in muscle with restoration of the proteolytic activity and without evident toxicity. In addition, calpain 3 was correctly targeted to the sarcomere. Moreover, its presence resulted in improvement of the histological features and in therapeutic efficacy at the physiological levels, including correction of atrophy and full rescue of the contractile force deficits. Our results establish the feasibility of AAV-mediated calpain 3 gene transfer as a therapeutic approach.     

The in vivo degradation of a ruthenium labelled polysaccharide-based hydrogel for bone tissue engineering

In this paper we report a new method that permitted for the first time to selectively track a polysaccharide-based hydrogel on bone tissue explants, several weeks after its implantation. The hydrogel, which was developed for bone healing and tissue engineering, was labelled with a ruthenium complex and implanted into rabbit bone defects in order to investigate its in vivo degradation. 1, 2, 3 and 8 weeks after surgery, the bone explants were analyzed by synchrotron X-ray microfluorescence, infrared mapping spectroscopy, scanning electron microscopy, and optical microscopy after histological coloration. The results showed that the labelled polysaccharide-based hydrogel was likely to undergo phagocytosis that seemed to occur from the edge to the center of the implantation site up to at least the 8th week.     

Highly efficient transduction of human plasmacytoid dendritic cells without phenotypic and functional maturation

Background  

Gene modified dendritic cells (DC) are able to modulate DC functions and induce therapeutic immunity or tolerance in an antigen-specific manner. Among the different DC subsets, plasmacytoid DC (pDC) are well known for their ability to recognize and respond to a variety of viruses by secreting high levels of type I interferon.     

Systemic lupus erythematosus in Egyptian children

The aim of the study was to study the characteristics of systemic lupus erythematosus (SLE) in the Egyptian population, comparing it to other populations. We retrospectively studied 207 patients with SLE diagnosed between 1990 and 2005. We obtained clinical features and laboratory data and analyzed them statistically. We studied 151 female and 56 male SLE patients. The female to male ratio was 2.7 to 1 and the mean age at presentation was 10 ± 2.7 years (range 2–16). The mean disease duration was 6.47 ± 3.74 years. At diagnosis, musculoskeletal, constitutional and mucocutaneous manifestations were the commonest features. During follow-up, the prevalence of nephritis (67%), hematological manifestations (44.9%), photosensitivity (44%), arthritis (39%), malar rash (38.2%), serositis (32.9%) and neuropsychiatric manifestations (24.25%) increased significantly. Those whose age of onset of the disease was ≤5 years (nine patients) had significantly more common hematological affection (P value = 0.0005). The characteristics of SLE in Egyptian patients show some similarities to other series of Middle Eastern countries, but with a lower female to male ratio. Disease onset below 5 years is extremely rare (4.35%), commonly presenting with hematological manifestations. The kidney was the commonest major internal organ involved, and also an important cause of death.