Microarray-based comparative genomic analyses of the human malaria parasite Plasmodium falciparum using Affymetrix arrays

Microarray-based comparative genomic hybridization (CGH) provides a powerful tool for whole genome analyses and the rapid detection of genomic variation that underlies virulence and disease. In the field of Plasmodium research, many of the parasite genomes that one might wish to study in a high throughput manner are not laboratory clones, but clinical isolates. One of the key limitations to the use of clinical samples in CGH, however, is the miniscule amounts of genomic DNA available. Here we describe the successful application of multiple displacement amplification (MDA), a non-PCR-based amplification method that exhibits clear advantages over all other currently available methods. Using MDA, CGH was performed on a panel of NF54 and IT/FCR3 clones, identifying previously published deletions on chromosomes 2 and 9 as well as polymorphism in genes associated with disease pathology.     

Hotspot for deletions in the CGG repeat region of FMR1 in fragile X patients

The fragile X syndrome is the most frequent cause of inheritedmental retardation. The molecular mechanism of the disorderis based on the expansion of a CGG repeat in the 5' UTR of theFMR1 gene In the majority of fragile X patients. The instabilityof this CGG repeat containing region is not restricted to theCGG repeat Itself but expands to the flanking region as well.We describe four unrelated fragile X patients that are mosaicfor both a full mutation and a small deletion in the CGG repeatcontaining region. Sequence analysis of the regions surroundingthe deletions showed that both the (CGG)_n repeat and some flankingsequences were missing in all four patients. The 5' breakpointsof the deletions were found to be located between 75–53bp proximal to the CGG repeat. This suggests the presence ofa hot spot region for deletions in the CGG repeat region ofthe FMR1 gene and emphasizes the instability of this regionIn the presence of an expanded CGG repeat.     

The development of an M antibody capture ELISA for rubella IgM

An M antibody capture enzyme-linked immunosorbent assay for rubella IgM was developed. The enzyme label was prepared from a monoclonal antibody raised against rubella haemagglutinin (Tedder et al., 1982). Paired sera from acute rubella infections and vaccines as well as sera from blood donors, antenatal patients and patients whose sera contained rheumatoid factor and patients with acute non-rubella infections were tested by this method.     

Selection in blood cells from female carriers of the fragile X syndrome: inverse correlation between age and proportion of active X chromosomes carrying the full mutation.

We have studied the patterns of mutation and X inactivation in female carriers of a fragile X mutation, to try to correlate them with various phenotypic features. We used a simple assay, which shows simultaneously the size of the mutation, its methylation status, and DNA fragments that represent the normal active and inactive X chromosomes. We have observed an age dependent process, whereby the 'full' fragile X mutation is found preferentially on the inactive X in leucocytes in adult females, but not in younger ones. This phenomenon was not observed in female carriers of a 'premutation', who have little phenotypic expression. Preliminary data suggest that young females who show preferential presence of a full mutation on the active X in leucocytes may be at increased risk for mental retardation. We have also obtained preliminary evidence for an age dependent decrease in the somatic heterogeneity of full mutations, possibly owing to selection for smaller mutated fragments. If confirmed, the latter phenomenon might account for the known decrease with age of the expression of the fragile site. Our observations suggest that a gene whose expression is affected by the presence of a full mutation (possibly the FMR-1 gene) has a cell autonomous function in leucocytes, leading to a slowly progressive selection for cells where the mutation is on the inactive X chromosome.     

Synergistic convergence of microbiota-specific systemic IgG and secretory IgA

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Segmentation automatique d’échographies trans-abdominales de prostate pour le recalage d''images

This article presents a method for automatic segmentation of prostate from abdominal freehand ultrasound images. A statistical model of prostate is estimated from a manually delineated images. The segmentation starts by smoothing the image to enhance edges by applying a morphological and adaptive filter which detects individual speckles and remove them, while it preserves valuable details. Then the boundary is initialised starting from the model and the final form is estimated by a simulated annealing optimisation algorithm. The performances of the algorithm were compared with manual segmentation by an expert, the average distance was 3.7 pixels and an overlap surface of 93%.     

A member of a conserved Plasmodium protein family with membrane-attack complex/perforin (MACPF)-like domains localizes to the micronemes of sporozoites

Pore-forming proteins are employed by many pathogens to achieve successful host colonization. Intracellular pathogens use pore-forming proteins to invade host cells, survive within and productively interact with host cells, and finally egress from host cells to infect new ones. The malaria-causing parasites of the genus Plasmodium evolved a number of life cycle stages that enter and replicate in distinct cell types within the mosquito vector and vertebrate host. Despite the fact that interaction with host-cell membranes is a central theme in the Plasmodium life cycle, little is known about parasite proteins that mediate such interactions. We identified a family of five related genes in the genome of the rodent malaria parasite Plasmodium yoelii encoding secreted proteins all bearing a single membrane-attack complex/perforin (MACPF)-like domain. Each protein is highly conserved among Plasmodium species. Gene expression analysis in P. yoelii and the human malaria parasite Plasmodium falciparum indicated that the family is not expressed in the parasites blood stages. However, one of the genes was significantly expressed in P. yoelii sporozoites, the stage transmitted by mosquito bite. The protein localized to the micronemes of sporozoites, organelles of the secretory invasion apparatus intimately involved in host-cell infection. MACPF-like proteins may play important roles in parasite interactions with the mosquito vector and transmission to the vertebrate host.     

Photobiomodulation therapy on expression of HSP70 protein and tissue repair in experimental acute Achilles tendinitis

Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in...     

Management of lower urinary tract fibroepithelial polyps in children

IntroductionFibroepithelial polyps (FEP) of the lower urinary tract are relatively common in adults but rare in children, with fewer than 250 cases reported in the literature to date.ObjectiveThe aim of this study was to address the experience of FEP management in children.Study designA retrospective multicenter review was undertaken in children with defined FEP of the lower urinary tract managed between 2008 and 2018. The data at 18 pediatric surgery centers were collected. Their demographic, radiological, surgical, and pathological information were reviewed.ResultsA total of 33 children (26 boys; 7 girls) were treated for FEP of the lower urinary tract at 13 centers. The most common presentation was urinary outflow as hematuria (41%), acute urinary retention (25%), dysuria (19%), or urinary infections (28%). A prenatal diagnosis was made for three patients with hydronephrosis. Almost all of the children (94%) underwent ultrasound imaging of the urinary tract as the first diagnostic examination, 23 (70%) of them also either had an MRI (15%), cystourethrography (25%), computerized tomography (6%), or cystoscopy (45%). Two of these children (6%) had a biopsy prior to the surgery. The median preoperative delay was 7.52 (range: 1–48) months. Most of the patients were treated endoscopically, although four (12.1%) had open surgery and two (6.1%) had an additional incision for specimen extraction. The median hospital stay was 1.5 (range: 1–10) days. There were no recurrences and no complications after a median follow-up of 13 (range: 1–34) months.DiscussionThe main limitation of our study is the retrospective design, although it is the largest one for this pathology.ConclusionThis series supports sonography as the most suitable diagnosis tool before endoscopy to confirm the diagnosis and to perform the resection for most FEP in children. This report confirms the recognized benign nature in the absence of recurrences.Level of EvidenceLevel V.